Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

28 files changed, 10637 insertions, 0 deletions

diff --git a/fs/orangefs/Kconfig b/fs/orangefs/Kconfig
new file mode 100644
index 000000000..890c0ae9a
--- /dev/null
+++ b/fs/orangefs/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ORANGEFS_FS
+	tristate "ORANGEFS (Powered by PVFS) support"
+	select FS_POSIX_ACL
+	help
+	   Orange is a parallel file system designed for use on high end
+	   computing (HEC) systems.
diff --git a/fs/orangefs/Makefile b/fs/orangefs/Makefile
new file mode 100644
index 000000000..9b6c50bb1
--- /dev/null
+++ b/fs/orangefs/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the ORANGEFS filesystem.
+#
+
+obj-$(CONFIG_ORANGEFS_FS) += orangefs.o
+
+orangefs-objs := acl.o file.o orangefs-cache.o orangefs-utils.o xattr.o \
+		 dcache.o inode.o orangefs-sysfs.o orangefs-mod.o super.o \
+		 devorangefs-req.o namei.o symlink.o dir.o orangefs-bufmap.o \
+		 orangefs-debugfs.o waitqueue.o
diff --git a/fs/orangefs/acl.c b/fs/orangefs/acl.c
new file mode 100644
index 000000000..605e5a350
--- /dev/null
+++ b/fs/orangefs/acl.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+#include <linux/posix_acl_xattr.h>
+
+struct posix_acl *orangefs_get_acl(struct inode *inode, int type, bool rcu)
+{
+	struct posix_acl *acl;
+	int ret;
+	char *key = NULL, *value = NULL;
+
+	if (rcu)
+		return ERR_PTR(-ECHILD);
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		key = XATTR_NAME_POSIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		key = XATTR_NAME_POSIX_ACL_DEFAULT;
+		break;
+	default:
+		gossip_err("orangefs_get_acl: bogus value of type %d\n", type);
+		return ERR_PTR(-EINVAL);
+	}
+	/*
+	 * Rather than incurring a network call just to determine the exact
+	 * length of the attribute, I just allocate a max length to save on
+	 * the network call. Conceivably, we could pass NULL to
+	 * orangefs_inode_getxattr() to probe the length of the value, but
+	 * I don't do that for now.
+	 */
+	value = kmalloc(ORANGEFS_MAX_XATTR_VALUELEN, GFP_KERNEL);
+	if (!value)
+		return ERR_PTR(-ENOMEM);
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "inode %pU, key %s, type %d\n",
+		     get_khandle_from_ino(inode),
+		     key,
+		     type);
+	ret = orangefs_inode_getxattr(inode, key, value,
+				      ORANGEFS_MAX_XATTR_VALUELEN);
+	/* if the key exists, convert it to an in-memory rep */
+	if (ret > 0) {
+		acl = posix_acl_from_xattr(&init_user_ns, value, ret);
+	} else if (ret == -ENODATA || ret == -ENOSYS) {
+		acl = NULL;
+	} else {
+		gossip_err("inode %pU retrieving acl's failed with error %d\n",
+			   get_khandle_from_ino(inode),
+			   ret);
+		acl = ERR_PTR(ret);
+	}
+	/* kfree(NULL) is safe, so don't worry if value ever got used */
+	kfree(value);
+	return acl;
+}
+
+static int __orangefs_set_acl(struct inode *inode, struct posix_acl *acl,
+			      int type)
+{
+	int error = 0;
+	void *value = NULL;
+	size_t size = 0;
+	const char *name = NULL;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name = XATTR_NAME_POSIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		name = XATTR_NAME_POSIX_ACL_DEFAULT;
+		break;
+	default:
+		gossip_err("%s: invalid type %d!\n", __func__, type);
+		return -EINVAL;
+	}
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "%s: inode %pU, key %s type %d\n",
+		     __func__, get_khandle_from_ino(inode),
+		     name,
+		     type);
+
+	if (acl) {
+		size = posix_acl_xattr_size(acl->a_count);
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return -ENOMEM;
+
+		error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
+		if (error < 0)
+			goto out;
+	}
+
+	gossip_debug(GOSSIP_ACL_DEBUG,
+		     "%s: name %s, value %p, size %zd, acl %p\n",
+		     __func__, name, value, size, acl);
+	/*
+	 * Go ahead and set the extended attribute now. NOTE: Suppose acl
+	 * was NULL, then value will be NULL and size will be 0 and that
+	 * will xlate to a removexattr. However, we don't want removexattr
+	 * complain if attributes does not exist.
+	 */
+	error = orangefs_inode_setxattr(inode, name, value, size, 0);
+
+out:
+	kfree(value);
+	if (!error)
+		set_cached_acl(inode, type, acl);
+	return error;
+}
+
+int orangefs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
+		     struct posix_acl *acl, int type)
+{
+	int error;
+	struct iattr iattr;
+	int rc;
+
+	memset(&iattr, 0, sizeof iattr);
+
+	if (type == ACL_TYPE_ACCESS && acl) {
+		/*
+		 * posix_acl_update_mode checks to see if the permissions
+		 * described by the ACL can be encoded into the
+		 * object's mode. If so, it sets "acl" to NULL
+		 * and "mode" to the new desired value. It is up to
+		 * us to propagate the new mode back to the server...
+		 */
+		error = posix_acl_update_mode(&init_user_ns, inode,
+					      &iattr.ia_mode, &acl);
+		if (error) {
+			gossip_err("%s: posix_acl_update_mode err: %d\n",
+				   __func__,
+				   error);
+			return error;
+		}
+
+		if (inode->i_mode != iattr.ia_mode)
+			iattr.ia_valid = ATTR_MODE;
+
+	}
+
+	rc = __orangefs_set_acl(inode, acl, type);
+
+	if (!rc && (iattr.ia_valid == ATTR_MODE))
+		rc = __orangefs_setattr(inode, &iattr);
+
+	return rc;
+}
+
+int orangefs_init_acl(struct inode *inode, struct inode *dir)
+{
+	struct posix_acl *default_acl, *acl;
+	umode_t mode = inode->i_mode;
+	struct iattr iattr;
+	int error = 0;
+
+	error = posix_acl_create(dir, &mode, &default_acl, &acl);
+	if (error)
+		return error;
+
+	if (default_acl) {
+		error = __orangefs_set_acl(inode, default_acl,
+					   ACL_TYPE_DEFAULT);
+		posix_acl_release(default_acl);
+	} else {
+		inode->i_default_acl = NULL;
+	}
+
+	if (acl) {
+		if (!error)
+			error = __orangefs_set_acl(inode, acl, ACL_TYPE_ACCESS);
+		posix_acl_release(acl);
+	} else {
+		inode->i_acl = NULL;
+	}
+
+	/* If mode of the inode was changed, then do a forcible ->setattr */
+	if (mode != inode->i_mode) {
+		memset(&iattr, 0, sizeof iattr);
+		inode->i_mode = mode;
+		iattr.ia_mode = mode;
+		iattr.ia_valid |= ATTR_MODE;
+		__orangefs_setattr(inode, &iattr);
+	}
+
+	return error;
+}
diff --git a/fs/orangefs/dcache.c b/fs/orangefs/dcache.c
new file mode 100644
index 000000000..8bbe9486e
--- /dev/null
+++ b/fs/orangefs/dcache.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Implementation of dentry (directory cache) functions.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+
+/* Returns 1 if dentry can still be trusted, else 0. */
+static int orangefs_revalidate_lookup(struct dentry *dentry)
+{
+	struct dentry *parent_dentry = dget_parent(dentry);
+	struct inode *parent_inode = parent_dentry->d_inode;
+	struct orangefs_inode_s *parent = ORANGEFS_I(parent_inode);
+	struct inode *inode = dentry->d_inode;
+	struct orangefs_kernel_op_s *new_op;
+	int ret = 0;
+	int err = 0;
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: attempting lookup.\n", __func__);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
+	if (!new_op) {
+		ret = -ENOMEM;
+		goto out_put_parent;
+	}
+
+	new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
+	new_op->upcall.req.lookup.parent_refn = parent->refn;
+	strncpy(new_op->upcall.req.lookup.d_name,
+		dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s:%s:%d interrupt flag [%d]\n",
+		     __FILE__,
+		     __func__,
+		     __LINE__,
+		     get_interruptible_flag(parent_inode));
+
+	err = service_operation(new_op, "orangefs_lookup",
+			get_interruptible_flag(parent_inode));
+
+	/* Positive dentry: reject if error or not the same inode. */
+	if (inode) {
+		if (err) {
+			gossip_debug(GOSSIP_DCACHE_DEBUG,
+			    "%s:%s:%d lookup failure.\n",
+			    __FILE__, __func__, __LINE__);
+			goto out_drop;
+		}
+		if (!match_handle(new_op->downcall.resp.lookup.refn.khandle,
+		    inode)) {
+			gossip_debug(GOSSIP_DCACHE_DEBUG,
+			    "%s:%s:%d no match.\n",
+			    __FILE__, __func__, __LINE__);
+			goto out_drop;
+		}
+
+	/* Negative dentry: reject if success or error other than ENOENT. */
+	} else {
+		gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: negative dentry.\n",
+		    __func__);
+		if (!err || err != -ENOENT) {
+			if (new_op->downcall.status != 0)
+				gossip_debug(GOSSIP_DCACHE_DEBUG,
+				    "%s:%s:%d lookup failure.\n",
+				    __FILE__, __func__, __LINE__);
+			goto out_drop;
+		}
+	}
+
+	orangefs_set_timeout(dentry);
+	ret = 1;
+out_release_op:
+	op_release(new_op);
+out_put_parent:
+	dput(parent_dentry);
+	return ret;
+out_drop:
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s:%s:%d revalidate failed\n",
+	    __FILE__, __func__, __LINE__);
+	goto out_release_op;
+}
+
+/*
+ * Verify that dentry is valid.
+ *
+ * Should return 1 if dentry can still be trusted, else 0.
+ */
+static int orangefs_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+	int ret;
+	unsigned long time = (unsigned long) dentry->d_fsdata;
+
+	if (time_before(jiffies, time))
+		return 1;
+
+	if (flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: called on dentry %p.\n",
+		     __func__, dentry);
+
+	/* skip root handle lookups. */
+	if (dentry->d_inode && is_root_handle(dentry->d_inode))
+		return 1;
+
+	/*
+	 * If this passes, the positive dentry still exists or the negative
+	 * dentry still does not exist.
+	 */
+	if (!orangefs_revalidate_lookup(dentry))
+		return 0;
+
+	/* We do not need to continue with negative dentries. */
+	if (!dentry->d_inode) {
+		gossip_debug(GOSSIP_DCACHE_DEBUG,
+		    "%s: negative dentry or positive dentry and inode valid.\n",
+		    __func__);
+		return 1;
+	}
+
+	/* Now we must perform a getattr to validate the inode contents. */
+
+	ret = orangefs_inode_check_changed(dentry->d_inode);
+	if (ret < 0) {
+		gossip_debug(GOSSIP_DCACHE_DEBUG, "%s:%s:%d getattr failure.\n",
+		    __FILE__, __func__, __LINE__);
+		return 0;
+	}
+	return !ret;
+}
+
+const struct dentry_operations orangefs_dentry_operations = {
+	.d_revalidate = orangefs_d_revalidate,
+};
diff --git a/fs/orangefs/devorangefs-req.c b/fs/orangefs/devorangefs-req.c
new file mode 100644
index 000000000..33ee8cb32
--- /dev/null
+++ b/fs/orangefs/devorangefs-req.c
@@ -0,0 +1,814 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * Changes by Acxiom Corporation to add protocol version to kernel
+ * communication, Copyright Acxiom Corporation, 2005.
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-dev-proto.h"
+#include "orangefs-bufmap.h"
+#include "orangefs-debugfs.h"
+
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+
+/* this file implements the /dev/pvfs2-req device node */
+
+uint32_t orangefs_userspace_version;
+
+static int open_access_count;
+
+static DEFINE_MUTEX(devreq_mutex);
+
+#define DUMP_DEVICE_ERROR()                                                   \
+do {                                                                          \
+	gossip_err("*****************************************************\n");\
+	gossip_err("ORANGEFS Device Error:  You cannot open the device file ");  \
+	gossip_err("\n/dev/%s more than once.  Please make sure that\nthere " \
+		   "are no ", ORANGEFS_REQDEVICE_NAME);                          \
+	gossip_err("instances of a program using this device\ncurrently "     \
+		   "running. (You must verify this!)\n");                     \
+	gossip_err("For example, you can use the lsof program as follows:\n");\
+	gossip_err("'lsof | grep %s' (run this as root)\n",                   \
+		   ORANGEFS_REQDEVICE_NAME);                                     \
+	gossip_err("  open_access_count = %d\n", open_access_count);          \
+	gossip_err("*****************************************************\n");\
+} while (0)
+
+static int hash_func(__u64 tag, int table_size)
+{
+	return do_div(tag, (unsigned int)table_size);
+}
+
+static void orangefs_devreq_add_op(struct orangefs_kernel_op_s *op)
+{
+	int index = hash_func(op->tag, hash_table_size);
+
+	list_add_tail(&op->list, &orangefs_htable_ops_in_progress[index]);
+}
+
+/*
+ * find the op with this tag and remove it from the in progress
+ * hash table.
+ */
+static struct orangefs_kernel_op_s *orangefs_devreq_remove_op(__u64 tag)
+{
+	struct orangefs_kernel_op_s *op, *next;
+	int index;
+
+	index = hash_func(tag, hash_table_size);
+
+	spin_lock(&orangefs_htable_ops_in_progress_lock);
+	list_for_each_entry_safe(op,
+				 next,
+				 &orangefs_htable_ops_in_progress[index],
+				 list) {
+		if (op->tag == tag && !op_state_purged(op) &&
+		    !op_state_given_up(op)) {
+			list_del_init(&op->list);
+			spin_unlock(&orangefs_htable_ops_in_progress_lock);
+			return op;
+		}
+	}
+
+	spin_unlock(&orangefs_htable_ops_in_progress_lock);
+	return NULL;
+}
+
+/* Returns whether any FS are still pending remounted */
+static int mark_all_pending_mounts(void)
+{
+	int unmounted = 1;
+	struct orangefs_sb_info_s *orangefs_sb = NULL;
+
+	spin_lock(&orangefs_superblocks_lock);
+	list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
+		/* All of these file system require a remount */
+		orangefs_sb->mount_pending = 1;
+		unmounted = 0;
+	}
+	spin_unlock(&orangefs_superblocks_lock);
+	return unmounted;
+}
+
+/*
+ * Determine if a given file system needs to be remounted or not
+ *  Returns -1 on error
+ *           0 if already mounted
+ *           1 if needs remount
+ */
+static int fs_mount_pending(__s32 fsid)
+{
+	int mount_pending = -1;
+	struct orangefs_sb_info_s *orangefs_sb = NULL;
+
+	spin_lock(&orangefs_superblocks_lock);
+	list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
+		if (orangefs_sb->fs_id == fsid) {
+			mount_pending = orangefs_sb->mount_pending;
+			break;
+		}
+	}
+	spin_unlock(&orangefs_superblocks_lock);
+	return mount_pending;
+}
+
+static int orangefs_devreq_open(struct inode *inode, struct file *file)
+{
+	int ret = -EINVAL;
+
+	/* in order to ensure that the filesystem driver sees correct UIDs */
+	if (file->f_cred->user_ns != &init_user_ns) {
+		gossip_err("%s: device cannot be opened outside init_user_ns\n",
+			   __func__);
+		goto out;
+	}
+
+	if (!(file->f_flags & O_NONBLOCK)) {
+		gossip_err("%s: device cannot be opened in blocking mode\n",
+			   __func__);
+		goto out;
+	}
+	ret = -EACCES;
+	gossip_debug(GOSSIP_DEV_DEBUG, "client-core: opening device\n");
+	mutex_lock(&devreq_mutex);
+
+	if (open_access_count == 0) {
+		open_access_count = 1;
+		ret = 0;
+	} else {
+		DUMP_DEVICE_ERROR();
+	}
+	mutex_unlock(&devreq_mutex);
+
+out:
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "pvfs2-client-core: open device complete (ret = %d)\n",
+		     ret);
+	return ret;
+}
+
+/* Function for read() callers into the device */
+static ssize_t orangefs_devreq_read(struct file *file,
+				 char __user *buf,
+				 size_t count, loff_t *offset)
+{
+	struct orangefs_kernel_op_s *op, *temp;
+	__s32 proto_ver = ORANGEFS_KERNEL_PROTO_VERSION;
+	static __s32 magic = ORANGEFS_DEVREQ_MAGIC;
+	struct orangefs_kernel_op_s *cur_op;
+	unsigned long ret;
+
+	/* We do not support blocking IO. */
+	if (!(file->f_flags & O_NONBLOCK)) {
+		gossip_err("%s: blocking read from client-core.\n",
+			   __func__);
+		return -EINVAL;
+	}
+
+	/*
+	 * The client will do an ioctl to find MAX_DEV_REQ_UPSIZE, then
+	 * always read with that size buffer.
+	 */
+	if (count != MAX_DEV_REQ_UPSIZE) {
+		gossip_err("orangefs: client-core tried to read wrong size\n");
+		return -EINVAL;
+	}
+
+	/* Check for an empty list before locking. */
+	if (list_empty(&orangefs_request_list))
+		return -EAGAIN;
+
+restart:
+	cur_op = NULL;
+	/* Get next op (if any) from top of list. */
+	spin_lock(&orangefs_request_list_lock);
+	list_for_each_entry_safe(op, temp, &orangefs_request_list, list) {
+		__s32 fsid;
+		/* This lock is held past the end of the loop when we break. */
+		spin_lock(&op->lock);
+		if (unlikely(op_state_purged(op) || op_state_given_up(op))) {
+			spin_unlock(&op->lock);
+			continue;
+		}
+
+		fsid = fsid_of_op(op);
+		if (fsid != ORANGEFS_FS_ID_NULL) {
+			int ret;
+			/* Skip ops whose filesystem needs to be mounted. */
+			ret = fs_mount_pending(fsid);
+			if (ret == 1) {
+				gossip_debug(GOSSIP_DEV_DEBUG,
+				    "%s: mount pending, skipping op tag "
+				    "%llu %s\n",
+				    __func__,
+				    llu(op->tag),
+				    get_opname_string(op));
+				spin_unlock(&op->lock);
+				continue;
+			/*
+			 * Skip ops whose filesystem we don't know about unless
+			 * it is being mounted or unmounted.  It is possible for
+			 * a filesystem we don't know about to be unmounted if
+			 * it fails to mount in the kernel after userspace has
+			 * been sent the mount request.
+			 */
+			/* XXX: is there a better way to detect this? */
+			} else if (ret == -1 &&
+				   !(op->upcall.type ==
+					ORANGEFS_VFS_OP_FS_MOUNT ||
+				     op->upcall.type ==
+					ORANGEFS_VFS_OP_GETATTR ||
+				     op->upcall.type ==
+					ORANGEFS_VFS_OP_FS_UMOUNT)) {
+				gossip_debug(GOSSIP_DEV_DEBUG,
+				    "orangefs: skipping op tag %llu %s\n",
+				    llu(op->tag), get_opname_string(op));
+				gossip_err(
+				    "orangefs: ERROR: fs_mount_pending %d\n",
+				    fsid);
+				spin_unlock(&op->lock);
+				continue;
+			}
+		}
+		/*
+		 * Either this op does not pertain to a filesystem, is mounting
+		 * a filesystem, or pertains to a mounted filesystem. Let it
+		 * through.
+		 */
+		cur_op = op;
+		break;
+	}
+
+	/*
+	 * At this point we either have a valid op and can continue or have not
+	 * found an op and must ask the client to try again later.
+	 */
+	if (!cur_op) {
+		spin_unlock(&orangefs_request_list_lock);
+		return -EAGAIN;
+	}
+
+	gossip_debug(GOSSIP_DEV_DEBUG, "%s: reading op tag %llu %s\n",
+		     __func__,
+		     llu(cur_op->tag),
+		     get_opname_string(cur_op));
+
+	/*
+	 * Such an op should never be on the list in the first place. If so, we
+	 * will abort.
+	 */
+	if (op_state_in_progress(cur_op) || op_state_serviced(cur_op)) {
+		gossip_err("orangefs: ERROR: Current op already queued.\n");
+		list_del_init(&cur_op->list);
+		spin_unlock(&cur_op->lock);
+		spin_unlock(&orangefs_request_list_lock);
+		return -EAGAIN;
+	}
+
+	list_del_init(&cur_op->list);
+	spin_unlock(&orangefs_request_list_lock);
+
+	spin_unlock(&cur_op->lock);
+
+	/* Push the upcall out. */
+	ret = copy_to_user(buf, &proto_ver, sizeof(__s32));
+	if (ret != 0)
+		goto error;
+	ret = copy_to_user(buf + sizeof(__s32), &magic, sizeof(__s32));
+	if (ret != 0)
+		goto error;
+	ret = copy_to_user(buf + 2 * sizeof(__s32),
+		&cur_op->tag,
+		sizeof(__u64));
+	if (ret != 0)
+		goto error;
+	ret = copy_to_user(buf + 2 * sizeof(__s32) + sizeof(__u64),
+		&cur_op->upcall,
+		sizeof(struct orangefs_upcall_s));
+	if (ret != 0)
+		goto error;
+
+	spin_lock(&orangefs_htable_ops_in_progress_lock);
+	spin_lock(&cur_op->lock);
+	if (unlikely(op_state_given_up(cur_op))) {
+		spin_unlock(&cur_op->lock);
+		spin_unlock(&orangefs_htable_ops_in_progress_lock);
+		complete(&cur_op->waitq);
+		goto restart;
+	}
+
+	/*
+	 * Set the operation to be in progress and move it between lists since
+	 * it has been sent to the client.
+	 */
+	set_op_state_inprogress(cur_op);
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "%s: 1 op:%s: op_state:%d: process:%s:\n",
+		     __func__,
+		     get_opname_string(cur_op),
+		     cur_op->op_state,
+		     current->comm);
+	orangefs_devreq_add_op(cur_op);
+	spin_unlock(&cur_op->lock);
+	spin_unlock(&orangefs_htable_ops_in_progress_lock);
+
+	/* The client only asks to read one size buffer. */
+	return MAX_DEV_REQ_UPSIZE;
+error:
+	/*
+	 * We were unable to copy the op data to the client. Put the op back in
+	 * list. If client has crashed, the op will be purged later when the
+	 * device is released.
+	 */
+	gossip_err("orangefs: Failed to copy data to user space\n");
+	spin_lock(&orangefs_request_list_lock);
+	spin_lock(&cur_op->lock);
+	if (likely(!op_state_given_up(cur_op))) {
+		set_op_state_waiting(cur_op);
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: 2 op:%s: op_state:%d: process:%s:\n",
+			     __func__,
+			     get_opname_string(cur_op),
+			     cur_op->op_state,
+			     current->comm);
+		list_add(&cur_op->list, &orangefs_request_list);
+		spin_unlock(&cur_op->lock);
+	} else {
+		spin_unlock(&cur_op->lock);
+		complete(&cur_op->waitq);
+	}
+	spin_unlock(&orangefs_request_list_lock);
+	return -EFAULT;
+}
+
+/*
+ * Function for writev() callers into the device.
+ *
+ * Userspace should have written:
+ *  - __u32 version
+ *  - __u32 magic
+ *  - __u64 tag
+ *  - struct orangefs_downcall_s
+ *  - trailer buffer (in the case of READDIR operations)
+ */
+static ssize_t orangefs_devreq_write_iter(struct kiocb *iocb,
+				      struct iov_iter *iter)
+{
+	ssize_t ret;
+	struct orangefs_kernel_op_s *op = NULL;
+	struct {
+		__u32 version;
+		__u32 magic;
+		__u64 tag;
+	} head;
+	int total = ret = iov_iter_count(iter);
+	int downcall_size = sizeof(struct orangefs_downcall_s);
+	int head_size = sizeof(head);
+
+	gossip_debug(GOSSIP_DEV_DEBUG, "%s: total:%d: ret:%zd:\n",
+		     __func__,
+		     total,
+		     ret);
+
+        if (total < MAX_DEV_REQ_DOWNSIZE) {
+		gossip_err("%s: total:%d: must be at least:%u:\n",
+			   __func__,
+			   total,
+			   (unsigned int) MAX_DEV_REQ_DOWNSIZE);
+		return -EFAULT;
+	}
+
+	if (!copy_from_iter_full(&head, head_size, iter)) {
+		gossip_err("%s: failed to copy head.\n", __func__);
+		return -EFAULT;
+	}
+
+	if (head.version < ORANGEFS_MINIMUM_USERSPACE_VERSION) {
+		gossip_err("%s: userspace claims version"
+			   "%d, minimum version required: %d.\n",
+			   __func__,
+			   head.version,
+			   ORANGEFS_MINIMUM_USERSPACE_VERSION);
+		return -EPROTO;
+	}
+
+	if (head.magic != ORANGEFS_DEVREQ_MAGIC) {
+		gossip_err("Error: Device magic number does not match.\n");
+		return -EPROTO;
+	}
+
+	if (!orangefs_userspace_version) {
+		orangefs_userspace_version = head.version;
+	} else if (orangefs_userspace_version != head.version) {
+		gossip_err("Error: userspace version changes\n");
+		return -EPROTO;
+	}
+
+	/* remove the op from the in progress hash table */
+	op = orangefs_devreq_remove_op(head.tag);
+	if (!op) {
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: No one's waiting for tag %llu\n",
+			     __func__, llu(head.tag));
+		return ret;
+	}
+
+	if (!copy_from_iter_full(&op->downcall, downcall_size, iter)) {
+		gossip_err("%s: failed to copy downcall.\n", __func__);
+		goto Efault;
+	}
+
+	if (op->downcall.status)
+		goto wakeup;
+
+	/*
+	 * We've successfully peeled off the head and the downcall.
+	 * Something has gone awry if total doesn't equal the
+	 * sum of head_size, downcall_size and trailer_size.
+	 */
+	if ((head_size + downcall_size + op->downcall.trailer_size) != total) {
+		gossip_err("%s: funky write, head_size:%d"
+			   ": downcall_size:%d: trailer_size:%lld"
+			   ": total size:%d:\n",
+			   __func__,
+			   head_size,
+			   downcall_size,
+			   op->downcall.trailer_size,
+			   total);
+		goto Efault;
+	}
+
+	/* Only READDIR operations should have trailers. */
+	if ((op->downcall.type != ORANGEFS_VFS_OP_READDIR) &&
+	    (op->downcall.trailer_size != 0)) {
+		gossip_err("%s: %x operation with trailer.",
+			   __func__,
+			   op->downcall.type);
+		goto Efault;
+	}
+
+	/* READDIR operations should always have trailers. */
+	if ((op->downcall.type == ORANGEFS_VFS_OP_READDIR) &&
+	    (op->downcall.trailer_size == 0)) {
+		gossip_err("%s: %x operation with no trailer.",
+			   __func__,
+			   op->downcall.type);
+		goto Efault;
+	}
+
+	if (op->downcall.type != ORANGEFS_VFS_OP_READDIR)
+		goto wakeup;
+
+	op->downcall.trailer_buf = vzalloc(op->downcall.trailer_size);
+	if (!op->downcall.trailer_buf)
+		goto Enomem;
+
+	if (!copy_from_iter_full(op->downcall.trailer_buf,
+			         op->downcall.trailer_size, iter)) {
+		gossip_err("%s: failed to copy trailer.\n", __func__);
+		vfree(op->downcall.trailer_buf);
+		goto Efault;
+	}
+
+wakeup:
+	/*
+	 * Return to vfs waitqueue, and back to service_operation
+	 * through wait_for_matching_downcall.
+	 */
+	spin_lock(&op->lock);
+	if (unlikely(op_is_cancel(op))) {
+		spin_unlock(&op->lock);
+		put_cancel(op);
+	} else if (unlikely(op_state_given_up(op))) {
+		spin_unlock(&op->lock);
+		complete(&op->waitq);
+	} else {
+		set_op_state_serviced(op);
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: op:%s: op_state:%d: process:%s:\n",
+			     __func__,
+			     get_opname_string(op),
+			     op->op_state,
+			     current->comm);
+		spin_unlock(&op->lock);
+	}
+	return ret;
+
+Efault:
+	op->downcall.status = -(ORANGEFS_ERROR_BIT | 9);
+	ret = -EFAULT;
+	goto wakeup;
+
+Enomem:
+	op->downcall.status = -(ORANGEFS_ERROR_BIT | 8);
+	ret = -ENOMEM;
+	goto wakeup;
+}
+
+/*
+ * NOTE: gets called when the last reference to this device is dropped.
+ * Using the open_access_count variable, we enforce a reference count
+ * on this file so that it can be opened by only one process at a time.
+ * the devreq_mutex is used to make sure all i/o has completed
+ * before we call orangefs_bufmap_finalize, and similar such tricky
+ * situations
+ */
+static int orangefs_devreq_release(struct inode *inode, struct file *file)
+{
+	int unmounted = 0;
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "%s:pvfs2-client-core: exiting, closing device\n",
+		     __func__);
+
+	mutex_lock(&devreq_mutex);
+	orangefs_bufmap_finalize();
+
+	open_access_count = -1;
+
+	unmounted = mark_all_pending_mounts();
+	gossip_debug(GOSSIP_DEV_DEBUG, "ORANGEFS Device Close: Filesystem(s) %s\n",
+		     (unmounted ? "UNMOUNTED" : "MOUNTED"));
+
+	purge_waiting_ops();
+	purge_inprogress_ops();
+
+	orangefs_bufmap_run_down();
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "pvfs2-client-core: device close complete\n");
+	open_access_count = 0;
+	orangefs_userspace_version = 0;
+	mutex_unlock(&devreq_mutex);
+	return 0;
+}
+
+int is_daemon_in_service(void)
+{
+	int in_service;
+
+	/*
+	 * What this function does is checks if client-core is alive
+	 * based on the access count we maintain on the device.
+	 */
+	mutex_lock(&devreq_mutex);
+	in_service = open_access_count == 1 ? 0 : -EIO;
+	mutex_unlock(&devreq_mutex);
+	return in_service;
+}
+
+bool __is_daemon_in_service(void)
+{
+	return open_access_count == 1;
+}
+
+static inline long check_ioctl_command(unsigned int command)
+{
+	/* Check for valid ioctl codes */
+	if (_IOC_TYPE(command) != ORANGEFS_DEV_MAGIC) {
+		gossip_err("device ioctl magic numbers don't match! Did you rebuild pvfs2-client-core/libpvfs2? [cmd %x, magic %x != %x]\n",
+			command,
+			_IOC_TYPE(command),
+			ORANGEFS_DEV_MAGIC);
+		return -EINVAL;
+	}
+	/* and valid ioctl commands */
+	if (_IOC_NR(command) >= ORANGEFS_DEV_MAXNR || _IOC_NR(command) <= 0) {
+		gossip_err("Invalid ioctl command number [%d >= %d]\n",
+			   _IOC_NR(command), ORANGEFS_DEV_MAXNR);
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static long dispatch_ioctl_command(unsigned int command, unsigned long arg)
+{
+	static __s32 magic = ORANGEFS_DEVREQ_MAGIC;
+	static __s32 max_up_size = MAX_DEV_REQ_UPSIZE;
+	static __s32 max_down_size = MAX_DEV_REQ_DOWNSIZE;
+	struct ORANGEFS_dev_map_desc user_desc;
+	int ret = 0;
+	int upstream_kmod = 1;
+	struct orangefs_sb_info_s *orangefs_sb;
+
+	/* mtmoore: add locking here */
+
+	switch (command) {
+	case ORANGEFS_DEV_GET_MAGIC:
+		return ((put_user(magic, (__s32 __user *) arg) == -EFAULT) ?
+			-EIO :
+			0);
+	case ORANGEFS_DEV_GET_MAX_UPSIZE:
+		return ((put_user(max_up_size,
+				  (__s32 __user *) arg) == -EFAULT) ?
+					-EIO :
+					0);
+	case ORANGEFS_DEV_GET_MAX_DOWNSIZE:
+		return ((put_user(max_down_size,
+				  (__s32 __user *) arg) == -EFAULT) ?
+					-EIO :
+					0);
+	case ORANGEFS_DEV_MAP:
+		ret = copy_from_user(&user_desc,
+				     (struct ORANGEFS_dev_map_desc __user *)
+				     arg,
+				     sizeof(struct ORANGEFS_dev_map_desc));
+		/* WTF -EIO and not -EFAULT? */
+		return ret ? -EIO : orangefs_bufmap_initialize(&user_desc);
+	case ORANGEFS_DEV_REMOUNT_ALL:
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: got ORANGEFS_DEV_REMOUNT_ALL\n",
+			     __func__);
+
+		/*
+		 * remount all mounted orangefs volumes to regain the lost
+		 * dynamic mount tables (if any) -- NOTE: this is done
+		 * without keeping the superblock list locked due to the
+		 * upcall/downcall waiting.  also, the request mutex is
+		 * used to ensure that no operations will be serviced until
+		 * all of the remounts are serviced (to avoid ops between
+		 * mounts to fail)
+		 */
+		ret = mutex_lock_interruptible(&orangefs_request_mutex);
+		if (ret < 0)
+			return ret;
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: priority remount in progress\n",
+			     __func__);
+		spin_lock(&orangefs_superblocks_lock);
+		list_for_each_entry(orangefs_sb, &orangefs_superblocks, list) {
+			/*
+			 * We have to drop the spinlock, so entries can be
+			 * removed.  They can't be freed, though, so we just
+			 * keep the forward pointers and zero the back ones -
+			 * that way we can get to the rest of the list.
+			 */
+			if (!orangefs_sb->list.prev)
+				continue;
+			gossip_debug(GOSSIP_DEV_DEBUG,
+				     "%s: Remounting SB %p\n",
+				     __func__,
+				     orangefs_sb);
+
+			spin_unlock(&orangefs_superblocks_lock);
+			ret = orangefs_remount(orangefs_sb);
+			spin_lock(&orangefs_superblocks_lock);
+			if (ret) {
+				gossip_debug(GOSSIP_DEV_DEBUG,
+					     "SB %p remount failed\n",
+					     orangefs_sb);
+				break;
+			}
+		}
+		spin_unlock(&orangefs_superblocks_lock);
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: priority remount complete\n",
+			     __func__);
+		mutex_unlock(&orangefs_request_mutex);
+		return ret;
+
+	case ORANGEFS_DEV_UPSTREAM:
+		ret = copy_to_user((void __user *)arg,
+				    &upstream_kmod,
+				    sizeof(upstream_kmod));
+
+		if (ret != 0)
+			return -EIO;
+		else
+			return ret;
+
+	case ORANGEFS_DEV_CLIENT_MASK:
+		return orangefs_debugfs_new_client_mask((void __user *)arg);
+	case ORANGEFS_DEV_CLIENT_STRING:
+		return orangefs_debugfs_new_client_string((void __user *)arg);
+	case ORANGEFS_DEV_DEBUG:
+		return orangefs_debugfs_new_debug((void __user *)arg);
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return -ENOIOCTLCMD;
+}
+
+static long orangefs_devreq_ioctl(struct file *file,
+			       unsigned int command, unsigned long arg)
+{
+	long ret;
+
+	/* Check for properly constructed commands */
+	ret = check_ioctl_command(command);
+	if (ret < 0)
+		return (int)ret;
+
+	return (int)dispatch_ioctl_command(command, arg);
+}
+
+#ifdef CONFIG_COMPAT		/* CONFIG_COMPAT is in .config */
+
+/*  Compat structure for the ORANGEFS_DEV_MAP ioctl */
+struct ORANGEFS_dev_map_desc32 {
+	compat_uptr_t ptr;
+	__s32 total_size;
+	__s32 size;
+	__s32 count;
+};
+
+/*
+ * 32 bit user-space apps' ioctl handlers when kernel modules
+ * is compiled as a 64 bit one
+ */
+static long orangefs_devreq_compat_ioctl(struct file *filp, unsigned int cmd,
+				      unsigned long args)
+{
+	long ret;
+
+	/* Check for properly constructed commands */
+	ret = check_ioctl_command(cmd);
+	if (ret < 0)
+		return ret;
+	if (cmd == ORANGEFS_DEV_MAP) {
+		struct ORANGEFS_dev_map_desc desc;
+		struct ORANGEFS_dev_map_desc32 d32;
+
+		if (copy_from_user(&d32, (void __user *)args, sizeof(d32)))
+			return -EFAULT;
+
+		desc.ptr = compat_ptr(d32.ptr);
+		desc.total_size = d32.total_size;
+		desc.size = d32.size;
+		desc.count = d32.count;
+		return orangefs_bufmap_initialize(&desc);
+	}
+	/* no other ioctl requires translation */
+	return dispatch_ioctl_command(cmd, args);
+}
+
+#endif /* CONFIG_COMPAT is in .config */
+
+static __poll_t orangefs_devreq_poll(struct file *file,
+				      struct poll_table_struct *poll_table)
+{
+	__poll_t poll_revent_mask = 0;
+
+	poll_wait(file, &orangefs_request_list_waitq, poll_table);
+
+	if (!list_empty(&orangefs_request_list))
+		poll_revent_mask |= EPOLLIN;
+	return poll_revent_mask;
+}
+
+/* the assigned character device major number */
+static int orangefs_dev_major;
+
+static const struct file_operations orangefs_devreq_file_operations = {
+	.owner = THIS_MODULE,
+	.read = orangefs_devreq_read,
+	.write_iter = orangefs_devreq_write_iter,
+	.open = orangefs_devreq_open,
+	.release = orangefs_devreq_release,
+	.unlocked_ioctl = orangefs_devreq_ioctl,
+
+#ifdef CONFIG_COMPAT		/* CONFIG_COMPAT is in .config */
+	.compat_ioctl = orangefs_devreq_compat_ioctl,
+#endif
+	.poll = orangefs_devreq_poll
+};
+
+/*
+ * Initialize orangefs device specific state:
+ * Must be called at module load time only
+ */
+int orangefs_dev_init(void)
+{
+	/* register orangefs-req device  */
+	orangefs_dev_major = register_chrdev(0,
+					  ORANGEFS_REQDEVICE_NAME,
+					  &orangefs_devreq_file_operations);
+	if (orangefs_dev_major < 0) {
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "Failed to register /dev/%s (error %d)\n",
+			     ORANGEFS_REQDEVICE_NAME, orangefs_dev_major);
+		return orangefs_dev_major;
+	}
+
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "*** /dev/%s character device registered ***\n",
+		     ORANGEFS_REQDEVICE_NAME);
+	gossip_debug(GOSSIP_DEV_DEBUG, "'mknod /dev/%s c %d 0'.\n",
+		     ORANGEFS_REQDEVICE_NAME, orangefs_dev_major);
+	return 0;
+}
+
+void orangefs_dev_cleanup(void)
+{
+	unregister_chrdev(orangefs_dev_major, ORANGEFS_REQDEVICE_NAME);
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "*** /dev/%s character device unregistered ***\n",
+		     ORANGEFS_REQDEVICE_NAME);
+}
diff --git a/fs/orangefs/dir.c b/fs/orangefs/dir.c
new file mode 100644
index 000000000..9cacce5d5
--- /dev/null
+++ b/fs/orangefs/dir.c
@@ -0,0 +1,404 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2017 Omnibond Systems, L.L.C.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+struct orangefs_dir_part {
+	struct orangefs_dir_part *next;
+	size_t len;
+};
+
+struct orangefs_dir {
+	__u64 token;
+	struct orangefs_dir_part *part;
+	loff_t end;
+	int error;
+};
+
+#define PART_SHIFT (24)
+#define PART_SIZE (1<<24)
+#define PART_MASK (~(PART_SIZE - 1))
+
+/*
+ * There can be up to 512 directory entries.  Each entry is encoded as
+ * follows:
+ * 4 bytes: string size (n)
+ * n bytes: string
+ * 1 byte: trailing zero
+ * padding to 8 bytes
+ * 16 bytes: khandle
+ * padding to 8 bytes
+ *
+ * The trailer_buf starts with a struct orangefs_readdir_response_s
+ * which must be skipped to get to the directory data.
+ *
+ * The data which is received from the userspace daemon is termed a
+ * part and is stored in a linked list in case more than one part is
+ * needed for a large directory.
+ *
+ * The position pointer (ctx->pos) encodes the part and offset on which
+ * to begin reading at.  Bits above PART_SHIFT encode the part and bits
+ * below PART_SHIFT encode the offset.  Parts are stored in a linked
+ * list which grows as data is received from the server.  The overhead
+ * associated with managing the list is presumed to be small compared to
+ * the overhead of communicating with the server.
+ *
+ * As data is received from the server, it is placed at the end of the
+ * part list.  Data is parsed from the current position as it is needed.
+ * When data is determined to be corrupt, it is either because the
+ * userspace component has sent back corrupt data or because the file
+ * pointer has been moved to an invalid location.  Since the two cannot
+ * be differentiated, return EIO.
+ *
+ * Part zero is synthesized to contains `.' and `..'.  Part one is the
+ * first part of the part list.
+ */
+
+static int do_readdir(struct orangefs_inode_s *oi,
+    struct orangefs_dir *od, struct dentry *dentry,
+    struct orangefs_kernel_op_s *op)
+{
+	struct orangefs_readdir_response_s *resp;
+	int bufi, r;
+
+	/*
+	 * Despite the badly named field, readdir does not use shared
+	 * memory.  However, there are a limited number of readdir
+	 * slots, which must be allocated here.  This flag simply tells
+	 * the op scheduler to return the op here for retry.
+	 */
+	op->uses_shared_memory = 1;
+	op->upcall.req.readdir.refn = oi->refn;
+	op->upcall.req.readdir.token = od->token;
+	op->upcall.req.readdir.max_dirent_count =
+	    ORANGEFS_MAX_DIRENT_COUNT_READDIR;
+
+again:
+	bufi = orangefs_readdir_index_get();
+	if (bufi < 0) {
+		od->error = bufi;
+		return bufi;
+	}
+
+	op->upcall.req.readdir.buf_index = bufi;
+
+	r = service_operation(op, "orangefs_readdir",
+	    get_interruptible_flag(dentry->d_inode));
+
+	orangefs_readdir_index_put(bufi);
+
+	if (op_state_purged(op)) {
+		if (r == -EAGAIN) {
+			vfree(op->downcall.trailer_buf);
+			goto again;
+		} else if (r == -EIO) {
+			vfree(op->downcall.trailer_buf);
+			od->error = r;
+			return r;
+		}
+	}
+
+	if (r < 0) {
+		vfree(op->downcall.trailer_buf);
+		od->error = r;
+		return r;
+	} else if (op->downcall.status) {
+		vfree(op->downcall.trailer_buf);
+		od->error = op->downcall.status;
+		return op->downcall.status;
+	}
+
+	/*
+	 * The maximum size is size per entry times the 512 entries plus
+	 * the header.  This is well under the limit.
+	 */
+	if (op->downcall.trailer_size > PART_SIZE) {
+		vfree(op->downcall.trailer_buf);
+		od->error = -EIO;
+		return -EIO;
+	}
+
+	resp = (struct orangefs_readdir_response_s *)
+	    op->downcall.trailer_buf;
+	od->token = resp->token;
+	return 0;
+}
+
+static int parse_readdir(struct orangefs_dir *od,
+    struct orangefs_kernel_op_s *op)
+{
+	struct orangefs_dir_part *part, *new;
+	size_t count;
+
+	count = 1;
+	part = od->part;
+	while (part) {
+		count++;
+		if (part->next)
+			part = part->next;
+		else
+			break;
+	}
+
+	new = (void *)op->downcall.trailer_buf;
+	new->next = NULL;
+	new->len = op->downcall.trailer_size -
+	    sizeof(struct orangefs_readdir_response_s);
+	if (!od->part)
+		od->part = new;
+	else
+		part->next = new;
+	count++;
+	od->end = count << PART_SHIFT;
+
+	return 0;
+}
+
+static int orangefs_dir_more(struct orangefs_inode_s *oi,
+    struct orangefs_dir *od, struct dentry *dentry)
+{
+	struct orangefs_kernel_op_s *op;
+	int r;
+
+	op = op_alloc(ORANGEFS_VFS_OP_READDIR);
+	if (!op) {
+		od->error = -ENOMEM;
+		return -ENOMEM;
+	}
+	r = do_readdir(oi, od, dentry, op);
+	if (r) {
+		od->error = r;
+		goto out;
+	}
+	r = parse_readdir(od, op);
+	if (r) {
+		od->error = r;
+		goto out;
+	}
+
+	od->error = 0;
+out:
+	op_release(op);
+	return od->error;
+}
+
+static int fill_from_part(struct orangefs_dir_part *part,
+    struct dir_context *ctx)
+{
+	const int offset = sizeof(struct orangefs_readdir_response_s);
+	struct orangefs_khandle *khandle;
+	__u32 *len, padlen;
+	loff_t i;
+	char *s;
+	i = ctx->pos & ~PART_MASK;
+
+	/* The file offset from userspace is too large. */
+	if (i > part->len)
+		return 1;
+
+	/*
+	 * If the seek pointer is positioned just before an entry it
+	 * should find the next entry.
+	 */
+	if (i % 8)
+		i = i + (8 - i%8)%8;
+
+	while (i < part->len) {
+		if (part->len < i + sizeof *len)
+			break;
+		len = (void *)part + offset + i;
+		/*
+		 * len is the size of the string itself.  padlen is the
+		 * total size of the encoded string.
+		 */
+		padlen = (sizeof *len + *len + 1) +
+		    (8 - (sizeof *len + *len + 1)%8)%8;
+		if (part->len < i + padlen + sizeof *khandle)
+			goto next;
+		s = (void *)part + offset + i + sizeof *len;
+		if (s[*len] != 0)
+			goto next;
+		khandle = (void *)part + offset + i + padlen;
+		if (!dir_emit(ctx, s, *len,
+		    orangefs_khandle_to_ino(khandle),
+		    DT_UNKNOWN))
+			return 0;
+		i += padlen + sizeof *khandle;
+		i = i + (8 - i%8)%8;
+		BUG_ON(i > part->len);
+		ctx->pos = (ctx->pos & PART_MASK) | i;
+		continue;
+next:
+		i += 8;
+	}
+	return 1;
+}
+
+static int orangefs_dir_fill(struct orangefs_inode_s *oi,
+    struct orangefs_dir *od, struct dentry *dentry,
+    struct dir_context *ctx)
+{
+	struct orangefs_dir_part *part;
+	size_t count;
+
+	count = ((ctx->pos & PART_MASK) >> PART_SHIFT) - 1;
+
+	part = od->part;
+	while (part->next && count) {
+		count--;
+		part = part->next;
+	}
+	/* This means the userspace file offset is invalid. */
+	if (count) {
+		od->error = -EIO;
+		return -EIO;
+	}
+
+	while (part && part->len) {
+		int r;
+		r = fill_from_part(part, ctx);
+		if (r < 0) {
+			od->error = r;
+			return r;
+		} else if (r == 0) {
+			/* Userspace buffer is full. */
+			break;
+		} else {
+			/*
+			 * The part ran out of data.  Move to the next
+			 * part. */
+			ctx->pos = (ctx->pos & PART_MASK) +
+			    (1 << PART_SHIFT);
+			part = part->next;
+		}
+	}
+	return 0;
+}
+
+static loff_t orangefs_dir_llseek(struct file *file, loff_t offset,
+    int whence)
+{
+	struct orangefs_dir *od = file->private_data;
+	/*
+	 * Delete the stored data so userspace sees new directory
+	 * entries.
+	 */
+	if (!whence && offset < od->end) {
+		struct orangefs_dir_part *part = od->part;
+		while (part) {
+			struct orangefs_dir_part *next = part->next;
+			vfree(part);
+			part = next;
+		}
+		od->token = ORANGEFS_ITERATE_START;
+		od->part = NULL;
+		od->end = 1 << PART_SHIFT;
+	}
+	return default_llseek(file, offset, whence);
+}
+
+static int orangefs_dir_iterate(struct file *file,
+    struct dir_context *ctx)
+{
+	struct orangefs_inode_s *oi;
+	struct orangefs_dir *od;
+	struct dentry *dentry;
+	int r;
+
+	dentry = file->f_path.dentry;
+	oi = ORANGEFS_I(dentry->d_inode);
+	od = file->private_data;
+
+	if (od->error)
+		return od->error;
+
+	if (ctx->pos == 0) {
+		if (!dir_emit_dot(file, ctx))
+			return 0;
+		ctx->pos++;
+	}
+	if (ctx->pos == 1) {
+		if (!dir_emit_dotdot(file, ctx))
+			return 0;
+		ctx->pos = 1 << PART_SHIFT;
+	}
+
+	/*
+	 * The seek position is in the first synthesized part but is not
+	 * valid.
+	 */
+	if ((ctx->pos & PART_MASK) == 0)
+		return -EIO;
+
+	r = 0;
+
+	/*
+	 * Must read more if the user has sought past what has been read
+	 * so far.  Stop a user who has sought past the end.
+	 */
+	while (od->token != ORANGEFS_ITERATE_END &&
+	    ctx->pos > od->end) {
+		r = orangefs_dir_more(oi, od, dentry);
+		if (r)
+			return r;
+	}
+	if (od->token == ORANGEFS_ITERATE_END && ctx->pos > od->end)
+		return -EIO;
+
+	/* Then try to fill if there's any left in the buffer. */
+	if (ctx->pos < od->end) {
+		r = orangefs_dir_fill(oi, od, dentry, ctx);
+		if (r)
+			return r;
+	}
+
+	/* Finally get some more and try to fill. */
+	if (od->token != ORANGEFS_ITERATE_END) {
+		r = orangefs_dir_more(oi, od, dentry);
+		if (r)
+			return r;
+		r = orangefs_dir_fill(oi, od, dentry, ctx);
+	}
+
+	return r;
+}
+
+static int orangefs_dir_open(struct inode *inode, struct file *file)
+{
+	struct orangefs_dir *od;
+	file->private_data = kmalloc(sizeof(struct orangefs_dir),
+	    GFP_KERNEL);
+	if (!file->private_data)
+		return -ENOMEM;
+	od = file->private_data;
+	od->token = ORANGEFS_ITERATE_START;
+	od->part = NULL;
+	od->end = 1 << PART_SHIFT;
+	od->error = 0;
+	return 0;
+}
+
+static int orangefs_dir_release(struct inode *inode, struct file *file)
+{
+	struct orangefs_dir *od = file->private_data;
+	struct orangefs_dir_part *part = od->part;
+	while (part) {
+		struct orangefs_dir_part *next = part->next;
+		vfree(part);
+		part = next;
+	}
+	kfree(od);
+	return 0;
+}
+
+const struct file_operations orangefs_dir_operations = {
+	.llseek = orangefs_dir_llseek,
+	.read = generic_read_dir,
+	.iterate_shared = orangefs_dir_iterate,
+	.open = orangefs_dir_open,
+	.release = orangefs_dir_release
+};
diff --git a/fs/orangefs/downcall.h b/fs/orangefs/downcall.h
new file mode 100644
index 000000000..ea2332e16
--- /dev/null
+++ b/fs/orangefs/downcall.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Definitions of downcalls used in Linux kernel module.
+ */
+
+#ifndef __DOWNCALL_H
+#define __DOWNCALL_H
+
+/*
+ * Sanitized the device-client core interaction
+ * for clean 32-64 bit usage
+ */
+struct orangefs_io_response {
+	__s64 amt_complete;
+};
+
+struct orangefs_lookup_response {
+	struct orangefs_object_kref refn;
+};
+
+struct orangefs_create_response {
+	struct orangefs_object_kref refn;
+};
+
+struct orangefs_symlink_response {
+	struct orangefs_object_kref refn;
+};
+
+struct orangefs_getattr_response {
+	struct ORANGEFS_sys_attr_s attributes;
+	char link_target[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_mkdir_response {
+	struct orangefs_object_kref refn;
+};
+
+struct orangefs_statfs_response {
+	__s64 block_size;
+	__s64 blocks_total;
+	__s64 blocks_avail;
+	__s64 files_total;
+	__s64 files_avail;
+};
+
+struct orangefs_fs_mount_response {
+	__s32 fs_id;
+	__s32 id;
+	struct orangefs_khandle root_khandle;
+};
+
+/* the getxattr response is the attribute value */
+struct orangefs_getxattr_response {
+	__s32 val_sz;
+	__s32 __pad1;
+	char val[ORANGEFS_MAX_XATTR_VALUELEN];
+};
+
+/* the listxattr response is an array of attribute names */
+struct orangefs_listxattr_response {
+	__s32 returned_count;
+	__s32 __pad1;
+	__u64 token;
+	char key[ORANGEFS_MAX_XATTR_LISTLEN * ORANGEFS_MAX_XATTR_NAMELEN];
+	__s32 keylen;
+	__s32 __pad2;
+	__s32 lengths[ORANGEFS_MAX_XATTR_LISTLEN];
+};
+
+struct orangefs_param_response {
+	union {
+		__s64 value64;
+		__s32 value32[2];
+	} u;
+};
+
+#define PERF_COUNT_BUF_SIZE 4096
+struct orangefs_perf_count_response {
+	char buffer[PERF_COUNT_BUF_SIZE];
+};
+
+#define FS_KEY_BUF_SIZE 4096
+struct orangefs_fs_key_response {
+	__s32 fs_keylen;
+	__s32 __pad1;
+	char fs_key[FS_KEY_BUF_SIZE];
+};
+
+/* 2.9.6 */
+struct orangefs_features_response {
+	__u64 features;
+};
+
+struct orangefs_downcall_s {
+	__s32 type;
+	__s32 status;
+	/* currently trailer is used only by readdir */
+	__s64 trailer_size;
+	char *trailer_buf;
+
+	union {
+		struct orangefs_io_response io;
+		struct orangefs_lookup_response lookup;
+		struct orangefs_create_response create;
+		struct orangefs_symlink_response sym;
+		struct orangefs_getattr_response getattr;
+		struct orangefs_mkdir_response mkdir;
+		struct orangefs_statfs_response statfs;
+		struct orangefs_fs_mount_response fs_mount;
+		struct orangefs_getxattr_response getxattr;
+		struct orangefs_listxattr_response listxattr;
+		struct orangefs_param_response param;
+		struct orangefs_perf_count_response perf_count;
+		struct orangefs_fs_key_response fs_key;
+		struct orangefs_features_response features;
+	} resp;
+};
+
+/*
+ * The readdir response comes in the trailer.  It is followed by the
+ * directory entries as described in dir.c.
+ */
+
+struct orangefs_readdir_response_s {
+	__u64 token;
+	__u64 directory_version;
+	__u32 __pad2;
+	__u32 orangefs_dirent_outcount;
+};
+
+#endif /* __DOWNCALL_H */
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
new file mode 100644
index 000000000..732661aa2
--- /dev/null
+++ b/fs/orangefs/file.c
@@ -0,0 +1,565 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * Copyright 2018 Omnibond Systems, L.L.C.
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Linux VFS file operations.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+
+static int flush_racache(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	int ret;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG,
+	    "%s: %pU: Handle is %pU | fs_id %d\n", __func__,
+	    get_khandle_from_ino(inode), &orangefs_inode->refn.khandle,
+	    orangefs_inode->refn.fs_id);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_RA_FLUSH);
+	if (!new_op)
+		return -ENOMEM;
+	new_op->upcall.req.ra_cache_flush.refn = orangefs_inode->refn;
+
+	ret = service_operation(new_op, "orangefs_flush_racache",
+	    get_interruptible_flag(inode));
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: got return value of %d\n",
+	    __func__, ret);
+
+	op_release(new_op);
+	return ret;
+}
+
+/*
+ * Post and wait for the I/O upcall to finish
+ */
+ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode,
+	loff_t *offset, struct iov_iter *iter, size_t total_size,
+	loff_t readahead_size, struct orangefs_write_range *wr,
+	int *index_return, struct file *file)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
+	struct orangefs_kernel_op_s *new_op = NULL;
+	int buffer_index;
+	ssize_t ret;
+	size_t copy_amount;
+	int open_for_read;
+	int open_for_write;
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO);
+	if (!new_op)
+		return -ENOMEM;
+
+	/* synchronous I/O */
+	new_op->upcall.req.io.readahead_size = readahead_size;
+	new_op->upcall.req.io.io_type = type;
+	new_op->upcall.req.io.refn = orangefs_inode->refn;
+
+populate_shared_memory:
+	/* get a shared buffer index */
+	buffer_index = orangefs_bufmap_get();
+	if (buffer_index < 0) {
+		ret = buffer_index;
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s: orangefs_bufmap_get failure (%zd)\n",
+			     __func__, ret);
+		goto out;
+	}
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "%s(%pU): GET op %p -> buffer_index %d\n",
+		     __func__,
+		     handle,
+		     new_op,
+		     buffer_index);
+
+	new_op->uses_shared_memory = 1;
+	new_op->upcall.req.io.buf_index = buffer_index;
+	new_op->upcall.req.io.count = total_size;
+	new_op->upcall.req.io.offset = *offset;
+	if (type == ORANGEFS_IO_WRITE && wr) {
+		new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid);
+		new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid);
+	}
+	/*
+	 * Orangefs has no open, and orangefs checks file permissions
+	 * on each file access. Posix requires that file permissions
+	 * be checked on open and nowhere else. Orangefs-through-the-kernel
+	 * needs to seem posix compliant.
+	 *
+	 * The VFS opens files, even if the filesystem provides no
+	 * method. We can see if a file was successfully opened for
+	 * read and or for write by looking at file->f_mode.
+	 *
+	 * When writes are flowing from the page cache, file is no
+	 * longer available. We can trust the VFS to have checked
+	 * file->f_mode before writing to the page cache.
+	 *
+	 * The mode of a file might change between when it is opened
+	 * and IO commences, or it might be created with an arbitrary mode.
+	 *
+	 * We'll make sure we don't hit EACCES during the IO stage by
+	 * using UID 0. Some of the time we have access without changing
+	 * to UID 0 - how to check?
+	 */
+	if (file) {
+		open_for_write = file->f_mode & FMODE_WRITE;
+		open_for_read = file->f_mode & FMODE_READ;
+	} else {
+		open_for_write = 1;
+		open_for_read = 0; /* not relevant? */
+	}
+	if ((type == ORANGEFS_IO_WRITE) && open_for_write)
+		new_op->upcall.uid = 0;
+	if ((type == ORANGEFS_IO_READ) && open_for_read)
+		new_op->upcall.uid = 0;
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "%s(%pU): offset: %llu total_size: %zd\n",
+		     __func__,
+		     handle,
+		     llu(*offset),
+		     total_size);
+	/*
+	 * Stage 1: copy the buffers into client-core's address space
+	 */
+	if (type == ORANGEFS_IO_WRITE && total_size) {
+		ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index,
+		    total_size);
+		if (ret < 0) {
+			gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n",
+			    __func__, (long)ret);
+			goto out;
+		}
+	}
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "%s(%pU): Calling post_io_request with tag (%llu)\n",
+		     __func__,
+		     handle,
+		     llu(new_op->tag));
+
+	/* Stage 2: Service the I/O operation */
+	ret = service_operation(new_op,
+				type == ORANGEFS_IO_WRITE ?
+					"file_write" :
+					"file_read",
+				get_interruptible_flag(inode));
+
+	/*
+	 * If service_operation() returns -EAGAIN #and# the operation was
+	 * purged from orangefs_request_list or htable_ops_in_progress, then
+	 * we know that the client was restarted, causing the shared memory
+	 * area to be wiped clean.  To restart a  write operation in this
+	 * case, we must re-copy the data from the user's iovec to a NEW
+	 * shared memory location. To restart a read operation, we must get
+	 * a new shared memory location.
+	 */
+	if (ret == -EAGAIN && op_state_purged(new_op)) {
+		orangefs_bufmap_put(buffer_index);
+		if (type == ORANGEFS_IO_WRITE)
+			iov_iter_revert(iter, total_size);
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s:going to repopulate_shared_memory.\n",
+			     __func__);
+		goto populate_shared_memory;
+	}
+
+	if (ret < 0) {
+		if (ret == -EINTR) {
+			/*
+			 * We can't return EINTR if any data was written,
+			 * it's not POSIX. It is minimally acceptable
+			 * to give a partial write, the way NFS does.
+			 *
+			 * It would be optimal to return all or nothing,
+			 * but if a userspace write is bigger than
+			 * an IO buffer, and the interrupt occurs
+			 * between buffer writes, that would not be
+			 * possible.
+			 */
+			switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) {
+			/*
+			 * If the op was waiting when the interrupt
+			 * occurred, then the client-core did not
+			 * trigger the write.
+			 */
+			case OP_VFS_STATE_WAITING:
+				if (*offset == 0)
+					ret = -EINTR;
+				else
+					ret = 0;
+				break;
+			/*
+			 * If the op was in progress when the interrupt
+			 * occurred, then the client-core was able to
+			 * trigger the write.
+			 */
+			case OP_VFS_STATE_INPROGR:
+				if (type == ORANGEFS_IO_READ)
+					ret = -EINTR;
+				else
+					ret = total_size;
+				break;
+			default:
+				gossip_err("%s: unexpected op state :%d:.\n",
+					   __func__,
+					   new_op->op_state);
+				ret = 0;
+				break;
+			}
+			gossip_debug(GOSSIP_FILE_DEBUG,
+				     "%s: got EINTR, state:%d: %p\n",
+				     __func__,
+				     new_op->op_state,
+				     new_op);
+		} else {
+			gossip_err("%s: error in %s handle %pU, returning %zd\n",
+				__func__,
+				type == ORANGEFS_IO_READ ?
+					"read from" : "write to",
+				handle, ret);
+		}
+		if (orangefs_cancel_op_in_progress(new_op))
+			return ret;
+
+		goto out;
+	}
+
+	/*
+	 * Stage 3: Post copy buffers from client-core's address space
+	 */
+	if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) {
+		/*
+		 * NOTE: the iovector can either contain addresses which
+		 *       can futher be kernel-space or user-space addresses.
+		 *       or it can pointers to struct page's
+		 */
+
+		copy_amount = new_op->downcall.resp.io.amt_complete;
+
+		ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index,
+			copy_amount);
+		if (ret < 0) {
+			gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n",
+			    __func__, (long)ret);
+			goto out;
+		}
+	}
+	gossip_debug(GOSSIP_FILE_DEBUG,
+	    "%s(%pU): Amount %s, returned by the sys-io call:%d\n",
+	    __func__,
+	    handle,
+	    type == ORANGEFS_IO_READ ?  "read" : "written",
+	    (int)new_op->downcall.resp.io.amt_complete);
+
+	ret = new_op->downcall.resp.io.amt_complete;
+
+out:
+	if (buffer_index >= 0) {
+		orangefs_bufmap_put(buffer_index);
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			"%s(%pU): PUT buffer_index %d\n",
+			__func__, handle, buffer_index);
+		buffer_index = -1;
+	}
+	op_release(new_op);
+	return ret;
+}
+
+int orangefs_revalidate_mapping(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct address_space *mapping = inode->i_mapping;
+	unsigned long *bitlock = &orangefs_inode->bitlock;
+	int ret;
+
+	while (1) {
+		ret = wait_on_bit(bitlock, 1, TASK_KILLABLE);
+		if (ret)
+			return ret;
+		spin_lock(&inode->i_lock);
+		if (test_bit(1, bitlock)) {
+			spin_unlock(&inode->i_lock);
+			continue;
+		}
+		if (!time_before(jiffies, orangefs_inode->mapping_time))
+			break;
+		spin_unlock(&inode->i_lock);
+		return 0;
+	}
+
+	set_bit(1, bitlock);
+	smp_wmb();
+	spin_unlock(&inode->i_lock);
+
+	unmap_mapping_range(mapping, 0, 0, 0);
+	ret = filemap_write_and_wait(mapping);
+	if (!ret)
+		ret = invalidate_inode_pages2(mapping);
+
+	orangefs_inode->mapping_time = jiffies +
+	    orangefs_cache_timeout_msecs*HZ/1000;
+
+	clear_bit(1, bitlock);
+	smp_mb__after_atomic();
+	wake_up_bit(bitlock, 1);
+
+	return ret;
+}
+
+static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
+    struct iov_iter *iter)
+{
+	int ret;
+	orangefs_stats.reads++;
+
+	down_read(&file_inode(iocb->ki_filp)->i_rwsem);
+	ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
+	if (ret)
+		goto out;
+
+	ret = generic_file_read_iter(iocb, iter);
+out:
+	up_read(&file_inode(iocb->ki_filp)->i_rwsem);
+	return ret;
+}
+
+static ssize_t orangefs_file_write_iter(struct kiocb *iocb,
+    struct iov_iter *iter)
+{
+	int ret;
+	orangefs_stats.writes++;
+
+	if (iocb->ki_pos > i_size_read(file_inode(iocb->ki_filp))) {
+		ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
+		if (ret)
+			return ret;
+	}
+
+	ret = generic_file_write_iter(iocb, iter);
+	return ret;
+}
+
+static vm_fault_t orangefs_fault(struct vm_fault *vmf)
+{
+	struct file *file = vmf->vma->vm_file;
+	int ret;
+	ret = orangefs_inode_getattr(file->f_mapping->host,
+	    ORANGEFS_GETATTR_SIZE);
+	if (ret == -ESTALE)
+		ret = -EIO;
+	if (ret) {
+		gossip_err("%s: orangefs_inode_getattr failed, "
+		    "ret:%d:.\n", __func__, ret);
+		return VM_FAULT_SIGBUS;
+	}
+	return filemap_fault(vmf);
+}
+
+static const struct vm_operations_struct orangefs_file_vm_ops = {
+	.fault = orangefs_fault,
+	.map_pages = filemap_map_pages,
+	.page_mkwrite = orangefs_page_mkwrite,
+};
+
+/*
+ * Memory map a region of a file.
+ */
+static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	int ret;
+
+	ret = orangefs_revalidate_mapping(file_inode(file));
+	if (ret)
+		return ret;
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "orangefs_file_mmap: called on %pD\n", file);
+
+	/* set the sequential readahead hint */
+	vma->vm_flags |= VM_SEQ_READ;
+	vma->vm_flags &= ~VM_RAND_READ;
+
+	file_accessed(file);
+	vma->vm_ops = &orangefs_file_vm_ops;
+	return 0;
+}
+
+#define mapping_nrpages(idata) ((idata)->nrpages)
+
+/*
+ * Called to notify the module that there are no more references to
+ * this file (i.e. no processes have it open).
+ *
+ * \note Not called when each file is closed.
+ */
+static int orangefs_file_release(struct inode *inode, struct file *file)
+{
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "orangefs_file_release: called on %pD\n",
+		     file);
+
+	/*
+	 * remove all associated inode pages from the page cache and
+	 * readahead cache (if any); this forces an expensive refresh of
+	 * data for the next caller of mmap (or 'get_block' accesses)
+	 */
+	if (mapping_nrpages(file->f_mapping)) {
+		if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) {
+			gossip_debug(GOSSIP_INODE_DEBUG,
+			    "calling flush_racache on %pU\n",
+			    get_khandle_from_ino(inode));
+			flush_racache(inode);
+			gossip_debug(GOSSIP_INODE_DEBUG,
+			    "flush_racache finished\n");
+		}
+
+	}
+	return 0;
+}
+
+/*
+ * Push all data for a specific file onto permanent storage.
+ */
+static int orangefs_fsync(struct file *file,
+		       loff_t start,
+		       loff_t end,
+		       int datasync)
+{
+	int ret;
+	struct orangefs_inode_s *orangefs_inode =
+		ORANGEFS_I(file_inode(file));
+	struct orangefs_kernel_op_s *new_op = NULL;
+
+	ret = filemap_write_and_wait_range(file_inode(file)->i_mapping,
+	    start, end);
+	if (ret < 0)
+		return ret;
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC);
+	if (!new_op)
+		return -ENOMEM;
+	new_op->upcall.req.fsync.refn = orangefs_inode->refn;
+
+	ret = service_operation(new_op,
+			"orangefs_fsync",
+			get_interruptible_flag(file_inode(file)));
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "orangefs_fsync got return value of %d\n",
+		     ret);
+
+	op_release(new_op);
+	return ret;
+}
+
+/*
+ * Change the file pointer position for an instance of an open file.
+ *
+ * \note If .llseek is overriden, we must acquire lock as described in
+ *       Documentation/filesystems/locking.rst.
+ *
+ * Future upgrade could support SEEK_DATA and SEEK_HOLE but would
+ * require much changes to the FS
+ */
+static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin)
+{
+	int ret = -EINVAL;
+	struct inode *inode = file_inode(file);
+
+	if (origin == SEEK_END) {
+		/*
+		 * revalidate the inode's file size.
+		 * NOTE: We are only interested in file size here,
+		 * so we set mask accordingly.
+		 */
+		ret = orangefs_inode_getattr(file->f_mapping->host,
+		    ORANGEFS_GETATTR_SIZE);
+		if (ret == -ESTALE)
+			ret = -EIO;
+		if (ret) {
+			gossip_debug(GOSSIP_FILE_DEBUG,
+				     "%s:%s:%d calling make bad inode\n",
+				     __FILE__,
+				     __func__,
+				     __LINE__);
+			return ret;
+		}
+	}
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "orangefs_file_llseek: offset is %ld | origin is %d"
+		     " | inode size is %lu\n",
+		     (long)offset,
+		     origin,
+		     (unsigned long)i_size_read(inode));
+
+	return generic_file_llseek(file, offset, origin);
+}
+
+/*
+ * Support local locks (locks that only this kernel knows about)
+ * if Orangefs was mounted -o local_lock.
+ */
+static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	int rc = -EINVAL;
+
+	if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) {
+		if (cmd == F_GETLK) {
+			rc = 0;
+			posix_test_lock(filp, fl);
+		} else {
+			rc = posix_lock_file(filp, fl, NULL);
+		}
+	}
+
+	return rc;
+}
+
+static int orangefs_flush(struct file *file, fl_owner_t id)
+{
+	/*
+	 * This is vfs_fsync_range(file, 0, LLONG_MAX, 0) without the
+	 * service_operation in orangefs_fsync.
+	 *
+	 * Do not send fsync to OrangeFS server on a close.  Do send fsync
+	 * on an explicit fsync call.  This duplicates historical OrangeFS
+	 * behavior.
+	 */
+	int r;
+
+	r = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX);
+	if (r > 0)
+		return 0;
+	else
+		return r;
+}
+
+/** ORANGEFS implementation of VFS file operations */
+const struct file_operations orangefs_file_operations = {
+	.llseek		= orangefs_file_llseek,
+	.read_iter	= orangefs_file_read_iter,
+	.write_iter	= orangefs_file_write_iter,
+	.lock		= orangefs_lock,
+	.mmap		= orangefs_file_mmap,
+	.open		= generic_file_open,
+	.splice_read    = generic_file_splice_read,
+	.splice_write   = iter_file_splice_write,
+	.flush		= orangefs_flush,
+	.release	= orangefs_file_release,
+	.fsync		= orangefs_fsync,
+};
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
new file mode 100644
index 000000000..b3bbb5a57
--- /dev/null
+++ b/fs/orangefs/inode.c
@@ -0,0 +1,1141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * Copyright 2018 Omnibond Systems, L.L.C.
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Linux VFS inode operations.
+ */
+
+#include <linux/blkdev.h>
+#include <linux/fileattr.h>
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+static int orangefs_writepage_locked(struct page *page,
+    struct writeback_control *wbc)
+{
+	struct inode *inode = page->mapping->host;
+	struct orangefs_write_range *wr = NULL;
+	struct iov_iter iter;
+	struct bio_vec bv;
+	size_t len, wlen;
+	ssize_t ret;
+	loff_t off;
+
+	set_page_writeback(page);
+
+	len = i_size_read(inode);
+	if (PagePrivate(page)) {
+		wr = (struct orangefs_write_range *)page_private(page);
+		WARN_ON(wr->pos >= len);
+		off = wr->pos;
+		if (off + wr->len > len)
+			wlen = len - off;
+		else
+			wlen = wr->len;
+	} else {
+		WARN_ON(1);
+		off = page_offset(page);
+		if (off + PAGE_SIZE > len)
+			wlen = len - off;
+		else
+			wlen = PAGE_SIZE;
+	}
+	/* Should've been handled in orangefs_invalidate_folio. */
+	WARN_ON(off == len || off + wlen > len);
+
+	bv.bv_page = page;
+	bv.bv_len = wlen;
+	bv.bv_offset = off % PAGE_SIZE;
+	WARN_ON(wlen == 0);
+	iov_iter_bvec(&iter, ITER_SOURCE, &bv, 1, wlen);
+
+	ret = wait_for_direct_io(ORANGEFS_IO_WRITE, inode, &off, &iter, wlen,
+	    len, wr, NULL, NULL);
+	if (ret < 0) {
+		SetPageError(page);
+		mapping_set_error(page->mapping, ret);
+	} else {
+		ret = 0;
+	}
+	kfree(detach_page_private(page));
+	return ret;
+}
+
+static int orangefs_writepage(struct page *page, struct writeback_control *wbc)
+{
+	int ret;
+	ret = orangefs_writepage_locked(page, wbc);
+	unlock_page(page);
+	end_page_writeback(page);
+	return ret;
+}
+
+struct orangefs_writepages {
+	loff_t off;
+	size_t len;
+	kuid_t uid;
+	kgid_t gid;
+	int maxpages;
+	int npages;
+	struct page **pages;
+	struct bio_vec *bv;
+};
+
+static int orangefs_writepages_work(struct orangefs_writepages *ow,
+    struct writeback_control *wbc)
+{
+	struct inode *inode = ow->pages[0]->mapping->host;
+	struct orangefs_write_range *wrp, wr;
+	struct iov_iter iter;
+	ssize_t ret;
+	size_t len;
+	loff_t off;
+	int i;
+
+	len = i_size_read(inode);
+
+	for (i = 0; i < ow->npages; i++) {
+		set_page_writeback(ow->pages[i]);
+		ow->bv[i].bv_page = ow->pages[i];
+		ow->bv[i].bv_len = min(page_offset(ow->pages[i]) + PAGE_SIZE,
+		    ow->off + ow->len) -
+		    max(ow->off, page_offset(ow->pages[i]));
+		if (i == 0)
+			ow->bv[i].bv_offset = ow->off -
+			    page_offset(ow->pages[i]);
+		else
+			ow->bv[i].bv_offset = 0;
+	}
+	iov_iter_bvec(&iter, ITER_SOURCE, ow->bv, ow->npages, ow->len);
+
+	WARN_ON(ow->off >= len);
+	if (ow->off + ow->len > len)
+		ow->len = len - ow->off;
+
+	off = ow->off;
+	wr.uid = ow->uid;
+	wr.gid = ow->gid;
+	ret = wait_for_direct_io(ORANGEFS_IO_WRITE, inode, &off, &iter, ow->len,
+	    0, &wr, NULL, NULL);
+	if (ret < 0) {
+		for (i = 0; i < ow->npages; i++) {
+			SetPageError(ow->pages[i]);
+			mapping_set_error(ow->pages[i]->mapping, ret);
+			if (PagePrivate(ow->pages[i])) {
+				wrp = (struct orangefs_write_range *)
+				    page_private(ow->pages[i]);
+				ClearPagePrivate(ow->pages[i]);
+				put_page(ow->pages[i]);
+				kfree(wrp);
+			}
+			end_page_writeback(ow->pages[i]);
+			unlock_page(ow->pages[i]);
+		}
+	} else {
+		ret = 0;
+		for (i = 0; i < ow->npages; i++) {
+			if (PagePrivate(ow->pages[i])) {
+				wrp = (struct orangefs_write_range *)
+				    page_private(ow->pages[i]);
+				ClearPagePrivate(ow->pages[i]);
+				put_page(ow->pages[i]);
+				kfree(wrp);
+			}
+			end_page_writeback(ow->pages[i]);
+			unlock_page(ow->pages[i]);
+		}
+	}
+	return ret;
+}
+
+static int orangefs_writepages_callback(struct page *page,
+    struct writeback_control *wbc, void *data)
+{
+	struct orangefs_writepages *ow = data;
+	struct orangefs_write_range *wr;
+	int ret;
+
+	if (!PagePrivate(page)) {
+		unlock_page(page);
+		/* It's not private so there's nothing to write, right? */
+		printk("writepages_callback not private!\n");
+		BUG();
+		return 0;
+	}
+	wr = (struct orangefs_write_range *)page_private(page);
+
+	ret = -1;
+	if (ow->npages == 0) {
+		ow->off = wr->pos;
+		ow->len = wr->len;
+		ow->uid = wr->uid;
+		ow->gid = wr->gid;
+		ow->pages[ow->npages++] = page;
+		ret = 0;
+		goto done;
+	}
+	if (!uid_eq(ow->uid, wr->uid) || !gid_eq(ow->gid, wr->gid)) {
+		orangefs_writepages_work(ow, wbc);
+		ow->npages = 0;
+		ret = -1;
+		goto done;
+	}
+	if (ow->off + ow->len == wr->pos) {
+		ow->len += wr->len;
+		ow->pages[ow->npages++] = page;
+		ret = 0;
+		goto done;
+	}
+done:
+	if (ret == -1) {
+		if (ow->npages) {
+			orangefs_writepages_work(ow, wbc);
+			ow->npages = 0;
+		}
+		ret = orangefs_writepage_locked(page, wbc);
+		mapping_set_error(page->mapping, ret);
+		unlock_page(page);
+		end_page_writeback(page);
+	} else {
+		if (ow->npages == ow->maxpages) {
+			orangefs_writepages_work(ow, wbc);
+			ow->npages = 0;
+		}
+	}
+	return ret;
+}
+
+static int orangefs_writepages(struct address_space *mapping,
+    struct writeback_control *wbc)
+{
+	struct orangefs_writepages *ow;
+	struct blk_plug plug;
+	int ret;
+	ow = kzalloc(sizeof(struct orangefs_writepages), GFP_KERNEL);
+	if (!ow)
+		return -ENOMEM;
+	ow->maxpages = orangefs_bufmap_size_query()/PAGE_SIZE;
+	ow->pages = kcalloc(ow->maxpages, sizeof(struct page *), GFP_KERNEL);
+	if (!ow->pages) {
+		kfree(ow);
+		return -ENOMEM;
+	}
+	ow->bv = kcalloc(ow->maxpages, sizeof(struct bio_vec), GFP_KERNEL);
+	if (!ow->bv) {
+		kfree(ow->pages);
+		kfree(ow);
+		return -ENOMEM;
+	}
+	blk_start_plug(&plug);
+	ret = write_cache_pages(mapping, wbc, orangefs_writepages_callback, ow);
+	if (ow->npages)
+		ret = orangefs_writepages_work(ow, wbc);
+	blk_finish_plug(&plug);
+	kfree(ow->pages);
+	kfree(ow->bv);
+	kfree(ow);
+	return ret;
+}
+
+static int orangefs_launder_folio(struct folio *);
+
+static void orangefs_readahead(struct readahead_control *rac)
+{
+	loff_t offset;
+	struct iov_iter iter;
+	struct inode *inode = rac->mapping->host;
+	struct xarray *i_pages;
+	struct page *page;
+	loff_t new_start = readahead_pos(rac);
+	int ret;
+	size_t new_len = 0;
+
+	loff_t bytes_remaining = inode->i_size - readahead_pos(rac);
+	loff_t pages_remaining = bytes_remaining / PAGE_SIZE;
+
+	if (pages_remaining >= 1024)
+		new_len = 4194304;
+	else if (pages_remaining > readahead_count(rac))
+		new_len = bytes_remaining;
+
+	if (new_len)
+		readahead_expand(rac, new_start, new_len);
+
+	offset = readahead_pos(rac);
+	i_pages = &rac->mapping->i_pages;
+
+	iov_iter_xarray(&iter, ITER_DEST, i_pages, offset, readahead_length(rac));
+
+	/* read in the pages. */
+	if ((ret = wait_for_direct_io(ORANGEFS_IO_READ, inode,
+			&offset, &iter, readahead_length(rac),
+			inode->i_size, NULL, NULL, rac->file)) < 0)
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			"%s: wait_for_direct_io failed. \n", __func__);
+	else
+		ret = 0;
+
+	/* clean up. */
+	while ((page = readahead_page(rac))) {
+		page_endio(page, false, ret);
+		put_page(page);
+	}
+}
+
+static int orangefs_read_folio(struct file *file, struct folio *folio)
+{
+	struct inode *inode = folio->mapping->host;
+	struct iov_iter iter;
+	struct bio_vec bv;
+	ssize_t ret;
+	loff_t off; /* offset of this folio in the file */
+
+	if (folio_test_dirty(folio))
+		orangefs_launder_folio(folio);
+
+	off = folio_pos(folio);
+	bv.bv_page = &folio->page;
+	bv.bv_len = folio_size(folio);
+	bv.bv_offset = 0;
+	iov_iter_bvec(&iter, ITER_DEST, &bv, 1, folio_size(folio));
+
+	ret = wait_for_direct_io(ORANGEFS_IO_READ, inode, &off, &iter,
+			folio_size(folio), inode->i_size, NULL, NULL, file);
+	/* this will only zero remaining unread portions of the folio data */
+	iov_iter_zero(~0U, &iter);
+	/* takes care of potential aliasing */
+	flush_dcache_folio(folio);
+	if (ret < 0) {
+		folio_set_error(folio);
+	} else {
+		folio_mark_uptodate(folio);
+		ret = 0;
+	}
+	/* unlock the folio after the ->read_folio() routine completes */
+	folio_unlock(folio);
+        return ret;
+}
+
+static int orangefs_write_begin(struct file *file,
+		struct address_space *mapping, loff_t pos, unsigned len,
+		struct page **pagep, void **fsdata)
+{
+	struct orangefs_write_range *wr;
+	struct folio *folio;
+	struct page *page;
+	pgoff_t index;
+	int ret;
+
+	index = pos >> PAGE_SHIFT;
+
+	page = grab_cache_page_write_begin(mapping, index);
+	if (!page)
+		return -ENOMEM;
+
+	*pagep = page;
+	folio = page_folio(page);
+
+	if (folio_test_dirty(folio) && !folio_test_private(folio)) {
+		/*
+		 * Should be impossible.  If it happens, launder the page
+		 * since we don't know what's dirty.  This will WARN in
+		 * orangefs_writepage_locked.
+		 */
+		ret = orangefs_launder_folio(folio);
+		if (ret)
+			return ret;
+	}
+	if (folio_test_private(folio)) {
+		struct orangefs_write_range *wr;
+		wr = folio_get_private(folio);
+		if (wr->pos + wr->len == pos &&
+		    uid_eq(wr->uid, current_fsuid()) &&
+		    gid_eq(wr->gid, current_fsgid())) {
+			wr->len += len;
+			goto okay;
+		} else {
+			ret = orangefs_launder_folio(folio);
+			if (ret)
+				return ret;
+		}
+	}
+
+	wr = kmalloc(sizeof *wr, GFP_KERNEL);
+	if (!wr)
+		return -ENOMEM;
+
+	wr->pos = pos;
+	wr->len = len;
+	wr->uid = current_fsuid();
+	wr->gid = current_fsgid();
+	folio_attach_private(folio, wr);
+okay:
+	return 0;
+}
+
+static int orangefs_write_end(struct file *file, struct address_space *mapping,
+    loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata)
+{
+	struct inode *inode = page->mapping->host;
+	loff_t last_pos = pos + copied;
+
+	/*
+	 * No need to use i_size_read() here, the i_size
+	 * cannot change under us because we hold the i_mutex.
+	 */
+	if (last_pos > inode->i_size)
+		i_size_write(inode, last_pos);
+
+	/* zero the stale part of the page if we did a short copy */
+	if (!PageUptodate(page)) {
+		unsigned from = pos & (PAGE_SIZE - 1);
+		if (copied < len) {
+			zero_user(page, from + copied, len - copied);
+		}
+		/* Set fully written pages uptodate. */
+		if (pos == page_offset(page) &&
+		    (len == PAGE_SIZE || pos + len == inode->i_size)) {
+			zero_user_segment(page, from + copied, PAGE_SIZE);
+			SetPageUptodate(page);
+		}
+	}
+
+	set_page_dirty(page);
+	unlock_page(page);
+	put_page(page);
+
+	mark_inode_dirty_sync(file_inode(file));
+	return copied;
+}
+
+static void orangefs_invalidate_folio(struct folio *folio,
+				 size_t offset, size_t length)
+{
+	struct orangefs_write_range *wr = folio_get_private(folio);
+
+	if (offset == 0 && length == PAGE_SIZE) {
+		kfree(folio_detach_private(folio));
+		return;
+	/* write range entirely within invalidate range (or equal) */
+	} else if (folio_pos(folio) + offset <= wr->pos &&
+	    wr->pos + wr->len <= folio_pos(folio) + offset + length) {
+		kfree(folio_detach_private(folio));
+		/* XXX is this right? only caller in fs */
+		folio_cancel_dirty(folio);
+		return;
+	/* invalidate range chops off end of write range */
+	} else if (wr->pos < folio_pos(folio) + offset &&
+	    wr->pos + wr->len <= folio_pos(folio) + offset + length &&
+	     folio_pos(folio) + offset < wr->pos + wr->len) {
+		size_t x;
+		x = wr->pos + wr->len - (folio_pos(folio) + offset);
+		WARN_ON(x > wr->len);
+		wr->len -= x;
+		wr->uid = current_fsuid();
+		wr->gid = current_fsgid();
+	/* invalidate range chops off beginning of write range */
+	} else if (folio_pos(folio) + offset <= wr->pos &&
+	    folio_pos(folio) + offset + length < wr->pos + wr->len &&
+	    wr->pos < folio_pos(folio) + offset + length) {
+		size_t x;
+		x = folio_pos(folio) + offset + length - wr->pos;
+		WARN_ON(x > wr->len);
+		wr->pos += x;
+		wr->len -= x;
+		wr->uid = current_fsuid();
+		wr->gid = current_fsgid();
+	/* invalidate range entirely within write range (punch hole) */
+	} else if (wr->pos < folio_pos(folio) + offset &&
+	    folio_pos(folio) + offset + length < wr->pos + wr->len) {
+		/* XXX what do we do here... should not WARN_ON */
+		WARN_ON(1);
+		/* punch hole */
+		/*
+		 * should we just ignore this and write it out anyway?
+		 * it hardly makes sense
+		 */
+		return;
+	/* non-overlapping ranges */
+	} else {
+		/* WARN if they do overlap */
+		if (!((folio_pos(folio) + offset + length <= wr->pos) ^
+		    (wr->pos + wr->len <= folio_pos(folio) + offset))) {
+			WARN_ON(1);
+			printk("invalidate range offset %llu length %zu\n",
+			    folio_pos(folio) + offset, length);
+			printk("write range offset %llu length %zu\n",
+			    wr->pos, wr->len);
+		}
+		return;
+	}
+
+	/*
+	 * Above there are returns where wr is freed or where we WARN.
+	 * Thus the following runs if wr was modified above.
+	 */
+
+	orangefs_launder_folio(folio);
+}
+
+static bool orangefs_release_folio(struct folio *folio, gfp_t foo)
+{
+	return !folio_test_private(folio);
+}
+
+static void orangefs_free_folio(struct folio *folio)
+{
+	kfree(folio_detach_private(folio));
+}
+
+static int orangefs_launder_folio(struct folio *folio)
+{
+	int r = 0;
+	struct writeback_control wbc = {
+		.sync_mode = WB_SYNC_ALL,
+		.nr_to_write = 0,
+	};
+	folio_wait_writeback(folio);
+	if (folio_clear_dirty_for_io(folio)) {
+		r = orangefs_writepage_locked(&folio->page, &wbc);
+		folio_end_writeback(folio);
+	}
+	return r;
+}
+
+static ssize_t orangefs_direct_IO(struct kiocb *iocb,
+				  struct iov_iter *iter)
+{
+	/*
+	 * Comment from original do_readv_writev:
+	 * Common entry point for read/write/readv/writev
+	 * This function will dispatch it to either the direct I/O
+	 * or buffered I/O path depending on the mount options and/or
+	 * augmented/extended metadata attached to the file.
+	 * Note: File extended attributes override any mount options.
+	 */
+	struct file *file = iocb->ki_filp;
+	loff_t pos = iocb->ki_pos;
+	enum ORANGEFS_io_type type = iov_iter_rw(iter) == WRITE ?
+            ORANGEFS_IO_WRITE : ORANGEFS_IO_READ;
+	loff_t *offset = &pos;
+	struct inode *inode = file->f_mapping->host;
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
+	size_t count = iov_iter_count(iter);
+	ssize_t total_count = 0;
+	ssize_t ret = -EINVAL;
+	int i = 0;
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		"%s-BEGIN(%pU): count(%d) after estimate_max_iovecs.\n",
+		__func__,
+		handle,
+		(int)count);
+
+	if (type == ORANGEFS_IO_WRITE) {
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s(%pU): proceeding with offset : %llu, "
+			     "size %d\n",
+			     __func__,
+			     handle,
+			     llu(*offset),
+			     (int)count);
+	}
+
+	if (count == 0) {
+		ret = 0;
+		goto out;
+	}
+
+	while (iov_iter_count(iter)) {
+		size_t each_count = iov_iter_count(iter);
+		size_t amt_complete;
+		i++;
+
+		/* how much to transfer in this loop iteration */
+		if (each_count > orangefs_bufmap_size_query())
+			each_count = orangefs_bufmap_size_query();
+
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s(%pU): size of each_count(%d)\n",
+			     __func__,
+			     handle,
+			     (int)each_count);
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s(%pU): BEFORE wait_for_io: offset is %d\n",
+			     __func__,
+			     handle,
+			     (int)*offset);
+
+		ret = wait_for_direct_io(type, inode, offset, iter,
+				each_count, 0, NULL, NULL, file);
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s(%pU): return from wait_for_io:%d\n",
+			     __func__,
+			     handle,
+			     (int)ret);
+
+		if (ret < 0)
+			goto out;
+
+		*offset += ret;
+		total_count += ret;
+		amt_complete = ret;
+
+		gossip_debug(GOSSIP_FILE_DEBUG,
+			     "%s(%pU): AFTER wait_for_io: offset is %d\n",
+			     __func__,
+			     handle,
+			     (int)*offset);
+
+		/*
+		 * if we got a short I/O operations,
+		 * fall out and return what we got so far
+		 */
+		if (amt_complete < each_count)
+			break;
+	} /*end while */
+
+out:
+	if (total_count > 0)
+		ret = total_count;
+	if (ret > 0) {
+		if (type == ORANGEFS_IO_READ) {
+			file_accessed(file);
+		} else {
+			file_update_time(file);
+			if (*offset > i_size_read(inode))
+				i_size_write(inode, *offset);
+		}
+	}
+
+	gossip_debug(GOSSIP_FILE_DEBUG,
+		     "%s(%pU): Value(%d) returned.\n",
+		     __func__,
+		     handle,
+		     (int)ret);
+
+	return ret;
+}
+
+/** ORANGEFS2 implementation of address space operations */
+static const struct address_space_operations orangefs_address_operations = {
+	.writepage = orangefs_writepage,
+	.readahead = orangefs_readahead,
+	.read_folio = orangefs_read_folio,
+	.writepages = orangefs_writepages,
+	.dirty_folio = filemap_dirty_folio,
+	.write_begin = orangefs_write_begin,
+	.write_end = orangefs_write_end,
+	.invalidate_folio = orangefs_invalidate_folio,
+	.release_folio = orangefs_release_folio,
+	.free_folio = orangefs_free_folio,
+	.launder_folio = orangefs_launder_folio,
+	.direct_IO = orangefs_direct_IO,
+};
+
+vm_fault_t orangefs_page_mkwrite(struct vm_fault *vmf)
+{
+	struct folio *folio = page_folio(vmf->page);
+	struct inode *inode = file_inode(vmf->vma->vm_file);
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	unsigned long *bitlock = &orangefs_inode->bitlock;
+	vm_fault_t ret;
+	struct orangefs_write_range *wr;
+
+	sb_start_pagefault(inode->i_sb);
+
+	if (wait_on_bit(bitlock, 1, TASK_KILLABLE)) {
+		ret = VM_FAULT_RETRY;
+		goto out;
+	}
+
+	folio_lock(folio);
+	if (folio_test_dirty(folio) && !folio_test_private(folio)) {
+		/*
+		 * Should be impossible.  If it happens, launder the folio
+		 * since we don't know what's dirty.  This will WARN in
+		 * orangefs_writepage_locked.
+		 */
+		if (orangefs_launder_folio(folio)) {
+			ret = VM_FAULT_LOCKED|VM_FAULT_RETRY;
+			goto out;
+		}
+	}
+	if (folio_test_private(folio)) {
+		wr = folio_get_private(folio);
+		if (uid_eq(wr->uid, current_fsuid()) &&
+		    gid_eq(wr->gid, current_fsgid())) {
+			wr->pos = page_offset(vmf->page);
+			wr->len = PAGE_SIZE;
+			goto okay;
+		} else {
+			if (orangefs_launder_folio(folio)) {
+				ret = VM_FAULT_LOCKED|VM_FAULT_RETRY;
+				goto out;
+			}
+		}
+	}
+	wr = kmalloc(sizeof *wr, GFP_KERNEL);
+	if (!wr) {
+		ret = VM_FAULT_LOCKED|VM_FAULT_RETRY;
+		goto out;
+	}
+	wr->pos = page_offset(vmf->page);
+	wr->len = PAGE_SIZE;
+	wr->uid = current_fsuid();
+	wr->gid = current_fsgid();
+	folio_attach_private(folio, wr);
+okay:
+
+	file_update_time(vmf->vma->vm_file);
+	if (folio->mapping != inode->i_mapping) {
+		folio_unlock(folio);
+		ret = VM_FAULT_LOCKED|VM_FAULT_NOPAGE;
+		goto out;
+	}
+
+	/*
+	 * We mark the folio dirty already here so that when freeze is in
+	 * progress, we are guaranteed that writeback during freezing will
+	 * see the dirty folio and writeprotect it again.
+	 */
+	folio_mark_dirty(folio);
+	folio_wait_stable(folio);
+	ret = VM_FAULT_LOCKED;
+out:
+	sb_end_pagefault(inode->i_sb);
+	return ret;
+}
+
+static int orangefs_setattr_size(struct inode *inode, struct iattr *iattr)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	loff_t orig_size;
+	int ret = -EINVAL;
+
+	gossip_debug(GOSSIP_INODE_DEBUG,
+		     "%s: %pU: Handle is %pU | fs_id %d | size is %llu\n",
+		     __func__,
+		     get_khandle_from_ino(inode),
+		     &orangefs_inode->refn.khandle,
+		     orangefs_inode->refn.fs_id,
+		     iattr->ia_size);
+
+	/* Ensure that we have a up to date size, so we know if it changed. */
+	ret = orangefs_inode_getattr(inode, ORANGEFS_GETATTR_SIZE);
+	if (ret == -ESTALE)
+		ret = -EIO;
+	if (ret) {
+		gossip_err("%s: orangefs_inode_getattr failed, ret:%d:.\n",
+		    __func__, ret);
+		return ret;
+	}
+	orig_size = i_size_read(inode);
+
+	/* This is truncate_setsize in a different order. */
+	truncate_pagecache(inode, iattr->ia_size);
+	i_size_write(inode, iattr->ia_size);
+	if (iattr->ia_size > orig_size)
+		pagecache_isize_extended(inode, orig_size, iattr->ia_size);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_TRUNCATE);
+	if (!new_op)
+		return -ENOMEM;
+
+	new_op->upcall.req.truncate.refn = orangefs_inode->refn;
+	new_op->upcall.req.truncate.size = (__s64) iattr->ia_size;
+
+	ret = service_operation(new_op,
+		__func__,
+		get_interruptible_flag(inode));
+
+	/*
+	 * the truncate has no downcall members to retrieve, but
+	 * the status value tells us if it went through ok or not
+	 */
+	gossip_debug(GOSSIP_INODE_DEBUG, "%s: ret:%d:\n", __func__, ret);
+
+	op_release(new_op);
+
+	if (ret != 0)
+		return ret;
+
+	if (orig_size != i_size_read(inode))
+		iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
+
+	return ret;
+}
+
+int __orangefs_setattr(struct inode *inode, struct iattr *iattr)
+{
+	int ret;
+
+	if (iattr->ia_valid & ATTR_MODE) {
+		if (iattr->ia_mode & (S_ISVTX)) {
+			if (is_root_handle(inode)) {
+				/*
+				 * allow sticky bit to be set on root (since
+				 * it shows up that way by default anyhow),
+				 * but don't show it to the server
+				 */
+				iattr->ia_mode -= S_ISVTX;
+			} else {
+				gossip_debug(GOSSIP_UTILS_DEBUG,
+					     "User attempted to set sticky bit on non-root directory; returning EINVAL.\n");
+				ret = -EINVAL;
+				goto out;
+			}
+		}
+		if (iattr->ia_mode & (S_ISUID)) {
+			gossip_debug(GOSSIP_UTILS_DEBUG,
+				     "Attempting to set setuid bit (not supported); returning EINVAL.\n");
+			ret = -EINVAL;
+			goto out;
+		}
+	}
+
+	if (iattr->ia_valid & ATTR_SIZE) {
+		ret = orangefs_setattr_size(inode, iattr);
+		if (ret)
+			goto out;
+	}
+
+again:
+	spin_lock(&inode->i_lock);
+	if (ORANGEFS_I(inode)->attr_valid) {
+		if (uid_eq(ORANGEFS_I(inode)->attr_uid, current_fsuid()) &&
+		    gid_eq(ORANGEFS_I(inode)->attr_gid, current_fsgid())) {
+			ORANGEFS_I(inode)->attr_valid = iattr->ia_valid;
+		} else {
+			spin_unlock(&inode->i_lock);
+			write_inode_now(inode, 1);
+			goto again;
+		}
+	} else {
+		ORANGEFS_I(inode)->attr_valid = iattr->ia_valid;
+		ORANGEFS_I(inode)->attr_uid = current_fsuid();
+		ORANGEFS_I(inode)->attr_gid = current_fsgid();
+	}
+	setattr_copy(&init_user_ns, inode, iattr);
+	spin_unlock(&inode->i_lock);
+	mark_inode_dirty(inode);
+
+	if (iattr->ia_valid & ATTR_MODE)
+		/* change mod on a file that has ACLs */
+		ret = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
+
+	ret = 0;
+out:
+	return ret;
+}
+
+/*
+ * Change attributes of an object referenced by dentry.
+ */
+int orangefs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *iattr)
+{
+	int ret;
+	gossip_debug(GOSSIP_INODE_DEBUG, "__orangefs_setattr: called on %pd\n",
+	    dentry);
+	ret = setattr_prepare(&init_user_ns, dentry, iattr);
+	if (ret)
+	        goto out;
+	ret = __orangefs_setattr(d_inode(dentry), iattr);
+	sync_inode_metadata(d_inode(dentry), 1);
+out:
+	gossip_debug(GOSSIP_INODE_DEBUG, "orangefs_setattr: returning %d\n",
+	    ret);
+	return ret;
+}
+
+/*
+ * Obtain attributes of an object given a dentry
+ */
+int orangefs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		     struct kstat *stat, u32 request_mask, unsigned int flags)
+{
+	int ret;
+	struct inode *inode = path->dentry->d_inode;
+
+	gossip_debug(GOSSIP_INODE_DEBUG,
+		     "orangefs_getattr: called on %pd mask %u\n",
+		     path->dentry, request_mask);
+
+	ret = orangefs_inode_getattr(inode,
+	    request_mask & STATX_SIZE ? ORANGEFS_GETATTR_SIZE : 0);
+	if (ret == 0) {
+		generic_fillattr(&init_user_ns, inode, stat);
+
+		/* override block size reported to stat */
+		if (!(request_mask & STATX_SIZE))
+			stat->result_mask &= ~STATX_SIZE;
+
+		generic_fill_statx_attr(inode, stat);
+	}
+	return ret;
+}
+
+int orangefs_permission(struct user_namespace *mnt_userns,
+			struct inode *inode, int mask)
+{
+	int ret;
+
+	if (mask & MAY_NOT_BLOCK)
+		return -ECHILD;
+
+	gossip_debug(GOSSIP_INODE_DEBUG, "%s: refreshing\n", __func__);
+
+	/* Make sure the permission (and other common attrs) are up to date. */
+	ret = orangefs_inode_getattr(inode, 0);
+	if (ret < 0)
+		return ret;
+
+	return generic_permission(&init_user_ns, inode, mask);
+}
+
+int orangefs_update_time(struct inode *inode, struct timespec64 *time, int flags)
+{
+	struct iattr iattr;
+	gossip_debug(GOSSIP_INODE_DEBUG, "orangefs_update_time: %pU\n",
+	    get_khandle_from_ino(inode));
+	generic_update_time(inode, time, flags);
+	memset(&iattr, 0, sizeof iattr);
+        if (flags & S_ATIME)
+		iattr.ia_valid |= ATTR_ATIME;
+	if (flags & S_CTIME)
+		iattr.ia_valid |= ATTR_CTIME;
+	if (flags & S_MTIME)
+		iattr.ia_valid |= ATTR_MTIME;
+	return __orangefs_setattr(inode, &iattr);
+}
+
+static int orangefs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
+{
+	u64 val = 0;
+	int ret;
+
+	gossip_debug(GOSSIP_FILE_DEBUG, "%s: called on %pd\n", __func__,
+		     dentry);
+
+	ret = orangefs_inode_getxattr(d_inode(dentry),
+				      "user.pvfs2.meta_hint",
+				      &val, sizeof(val));
+	if (ret < 0 && ret != -ENODATA)
+		return ret;
+
+	gossip_debug(GOSSIP_FILE_DEBUG, "%s: flags=%u\n", __func__, (u32) val);
+
+	fileattr_fill_flags(fa, val);
+	return 0;
+}
+
+static int orangefs_fileattr_set(struct user_namespace *mnt_userns,
+				 struct dentry *dentry, struct fileattr *fa)
+{
+	u64 val = 0;
+
+	gossip_debug(GOSSIP_FILE_DEBUG, "%s: called on %pd\n", __func__,
+		     dentry);
+	/*
+	 * ORANGEFS_MIRROR_FL is set internally when the mirroring mode is
+	 * turned on for a file. The user is not allowed to turn on this bit,
+	 * but the bit is present if the user first gets the flags and then
+	 * updates the flags with some new settings. So, we ignore it in the
+	 * following edit. bligon.
+	 */
+	if (fileattr_has_fsx(fa) ||
+	    (fa->flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NOATIME_FL | ORANGEFS_MIRROR_FL))) {
+		gossip_err("%s: only supports setting one of FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NOATIME_FL\n",
+			   __func__);
+		return -EOPNOTSUPP;
+	}
+	val = fa->flags;
+	gossip_debug(GOSSIP_FILE_DEBUG, "%s: flags=%u\n", __func__, (u32) val);
+	return orangefs_inode_setxattr(d_inode(dentry),
+				       "user.pvfs2.meta_hint",
+				       &val, sizeof(val), 0);
+}
+
+/* ORANGEFS2 implementation of VFS inode operations for files */
+static const struct inode_operations orangefs_file_inode_operations = {
+	.get_acl = orangefs_get_acl,
+	.set_acl = orangefs_set_acl,
+	.setattr = orangefs_setattr,
+	.getattr = orangefs_getattr,
+	.listxattr = orangefs_listxattr,
+	.permission = orangefs_permission,
+	.update_time = orangefs_update_time,
+	.fileattr_get = orangefs_fileattr_get,
+	.fileattr_set = orangefs_fileattr_set,
+};
+
+static int orangefs_init_iops(struct inode *inode)
+{
+	inode->i_mapping->a_ops = &orangefs_address_operations;
+
+	switch (inode->i_mode & S_IFMT) {
+	case S_IFREG:
+		inode->i_op = &orangefs_file_inode_operations;
+		inode->i_fop = &orangefs_file_operations;
+		break;
+	case S_IFLNK:
+		inode->i_op = &orangefs_symlink_inode_operations;
+		break;
+	case S_IFDIR:
+		inode->i_op = &orangefs_dir_inode_operations;
+		inode->i_fop = &orangefs_dir_operations;
+		break;
+	default:
+		gossip_debug(GOSSIP_INODE_DEBUG,
+			     "%s: unsupported mode\n",
+			     __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * Given an ORANGEFS object identifier (fsid, handle), convert it into
+ * a ino_t type that will be used as a hash-index from where the handle will
+ * be searched for in the VFS hash table of inodes.
+ */
+static inline ino_t orangefs_handle_hash(struct orangefs_object_kref *ref)
+{
+	if (!ref)
+		return 0;
+	return orangefs_khandle_to_ino(&(ref->khandle));
+}
+
+/*
+ * Called to set up an inode from iget5_locked.
+ */
+static int orangefs_set_inode(struct inode *inode, void *data)
+{
+	struct orangefs_object_kref *ref = (struct orangefs_object_kref *) data;
+	ORANGEFS_I(inode)->refn.fs_id = ref->fs_id;
+	ORANGEFS_I(inode)->refn.khandle = ref->khandle;
+	ORANGEFS_I(inode)->attr_valid = 0;
+	hash_init(ORANGEFS_I(inode)->xattr_cache);
+	ORANGEFS_I(inode)->mapping_time = jiffies - 1;
+	ORANGEFS_I(inode)->bitlock = 0;
+	return 0;
+}
+
+/*
+ * Called to determine if handles match.
+ */
+static int orangefs_test_inode(struct inode *inode, void *data)
+{
+	struct orangefs_object_kref *ref = (struct orangefs_object_kref *) data;
+	struct orangefs_inode_s *orangefs_inode = NULL;
+
+	orangefs_inode = ORANGEFS_I(inode);
+	/* test handles and fs_ids... */
+	return (!ORANGEFS_khandle_cmp(&(orangefs_inode->refn.khandle),
+				&(ref->khandle)) &&
+			orangefs_inode->refn.fs_id == ref->fs_id);
+}
+
+/*
+ * Front-end to lookup the inode-cache maintained by the VFS using the ORANGEFS
+ * file handle.
+ *
+ * @sb: the file system super block instance.
+ * @ref: The ORANGEFS object for which we are trying to locate an inode.
+ */
+struct inode *orangefs_iget(struct super_block *sb,
+		struct orangefs_object_kref *ref)
+{
+	struct inode *inode = NULL;
+	unsigned long hash;
+	int error;
+
+	hash = orangefs_handle_hash(ref);
+	inode = iget5_locked(sb,
+			hash,
+			orangefs_test_inode,
+			orangefs_set_inode,
+			ref);
+
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	error = orangefs_inode_getattr(inode, ORANGEFS_GETATTR_NEW);
+	if (error) {
+		iget_failed(inode);
+		return ERR_PTR(error);
+	}
+
+	inode->i_ino = hash;	/* needed for stat etc */
+	orangefs_init_iops(inode);
+	unlock_new_inode(inode);
+
+	gossip_debug(GOSSIP_INODE_DEBUG,
+		     "iget handle %pU, fsid %d hash %ld i_ino %lu\n",
+		     &ref->khandle,
+		     ref->fs_id,
+		     hash,
+		     inode->i_ino);
+
+	return inode;
+}
+
+/*
+ * Allocate an inode for a newly created file and insert it into the inode hash.
+ */
+struct inode *orangefs_new_inode(struct super_block *sb, struct inode *dir,
+		int mode, dev_t dev, struct orangefs_object_kref *ref)
+{
+	unsigned long hash = orangefs_handle_hash(ref);
+	struct inode *inode;
+	int error;
+
+	gossip_debug(GOSSIP_INODE_DEBUG,
+		     "%s:(sb is %p | MAJOR(dev)=%u | MINOR(dev)=%u mode=%o)\n",
+		     __func__,
+		     sb,
+		     MAJOR(dev),
+		     MINOR(dev),
+		     mode);
+
+	inode = new_inode(sb);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	orangefs_set_inode(inode, ref);
+	inode->i_ino = hash;	/* needed for stat etc */
+
+	error = orangefs_inode_getattr(inode, ORANGEFS_GETATTR_NEW);
+	if (error)
+		goto out_iput;
+
+	orangefs_init_iops(inode);
+	inode->i_rdev = dev;
+
+	error = insert_inode_locked4(inode, hash, orangefs_test_inode, ref);
+	if (error < 0)
+		goto out_iput;
+
+	gossip_debug(GOSSIP_INODE_DEBUG,
+		     "Initializing ACL's for inode %pU\n",
+		     get_khandle_from_ino(inode));
+	orangefs_init_acl(inode, dir);
+	return inode;
+
+out_iput:
+	iput(inode);
+	return ERR_PTR(error);
+}
diff --git a/fs/orangefs/namei.c b/fs/orangefs/namei.c
new file mode 100644
index 000000000..600e8eee5
--- /dev/null
+++ b/fs/orangefs/namei.c
@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Linux VFS namei operations.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+
+/*
+ * Get a newly allocated inode to go with a negative dentry.
+ */
+static int orangefs_create(struct user_namespace *mnt_userns,
+			struct inode *dir,
+			struct dentry *dentry,
+			umode_t mode,
+			bool exclusive)
+{
+	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
+	struct orangefs_kernel_op_s *new_op;
+	struct orangefs_object_kref ref;
+	struct inode *inode;
+	struct iattr iattr;
+	int ret;
+
+	gossip_debug(GOSSIP_NAME_DEBUG, "%s: %pd\n",
+		     __func__,
+		     dentry);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_CREATE);
+	if (!new_op)
+		return -ENOMEM;
+
+	new_op->upcall.req.create.parent_refn = parent->refn;
+
+	fill_default_sys_attrs(new_op->upcall.req.create.attributes,
+			       ORANGEFS_TYPE_METAFILE, mode);
+
+	strncpy(new_op->upcall.req.create.d_name,
+		dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
+
+	ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: %pd: handle:%pU: fsid:%d: new_op:%p: ret:%d:\n",
+		     __func__,
+		     dentry,
+		     &new_op->downcall.resp.create.refn.khandle,
+		     new_op->downcall.resp.create.refn.fs_id,
+		     new_op,
+		     ret);
+
+	if (ret < 0)
+		goto out;
+
+	ref = new_op->downcall.resp.create.refn;
+
+	inode = orangefs_new_inode(dir->i_sb, dir, S_IFREG | mode, 0, &ref);
+	if (IS_ERR(inode)) {
+		gossip_err("%s: Failed to allocate inode for file :%pd:\n",
+			   __func__,
+			   dentry);
+		ret = PTR_ERR(inode);
+		goto out;
+	}
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: Assigned inode :%pU: for file :%pd:\n",
+		     __func__,
+		     get_khandle_from_ino(inode),
+		     dentry);
+
+	d_instantiate_new(dentry, inode);
+	orangefs_set_timeout(dentry);
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: dentry instantiated for %pd\n",
+		     __func__,
+		     dentry);
+
+	memset(&iattr, 0, sizeof iattr);
+	iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
+	iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
+	__orangefs_setattr(dir, &iattr);
+	ret = 0;
+out:
+	op_release(new_op);
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: %pd: returning %d\n",
+		     __func__,
+		     dentry,
+		     ret);
+	return ret;
+}
+
+/*
+ * Attempt to resolve an object name (dentry->d_name), parent handle, and
+ * fsid into a handle for the object.
+ */
+static struct dentry *orangefs_lookup(struct inode *dir, struct dentry *dentry,
+				   unsigned int flags)
+{
+	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
+	struct orangefs_kernel_op_s *new_op;
+	struct inode *inode;
+	int ret = -EINVAL;
+
+	/*
+	 * in theory we could skip a lookup here (if the intent is to
+	 * create) in order to avoid a potentially failed lookup, but
+	 * leaving it in can skip a valid lookup and try to create a file
+	 * that already exists (e.g. the vfs already handles checking for
+	 * -EEXIST on O_EXCL opens, which is broken if we skip this lookup
+	 * in the create path)
+	 */
+	gossip_debug(GOSSIP_NAME_DEBUG, "%s called on %pd\n",
+		     __func__, dentry);
+
+	if (dentry->d_name.len > (ORANGEFS_NAME_MAX - 1))
+		return ERR_PTR(-ENAMETOOLONG);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
+	if (!new_op)
+		return ERR_PTR(-ENOMEM);
+
+	new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
+
+	gossip_debug(GOSSIP_NAME_DEBUG, "%s:%s:%d using parent %pU\n",
+		     __FILE__,
+		     __func__,
+		     __LINE__,
+		     &parent->refn.khandle);
+	new_op->upcall.req.lookup.parent_refn = parent->refn;
+
+	strncpy(new_op->upcall.req.lookup.d_name, dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: doing lookup on %s under %pU,%d\n",
+		     __func__,
+		     new_op->upcall.req.lookup.d_name,
+		     &new_op->upcall.req.lookup.parent_refn.khandle,
+		     new_op->upcall.req.lookup.parent_refn.fs_id);
+
+	ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Lookup Got %pU, fsid %d (ret=%d)\n",
+		     &new_op->downcall.resp.lookup.refn.khandle,
+		     new_op->downcall.resp.lookup.refn.fs_id,
+		     ret);
+
+	if (ret == 0) {
+		orangefs_set_timeout(dentry);
+		inode = orangefs_iget(dir->i_sb, &new_op->downcall.resp.lookup.refn);
+	} else if (ret == -ENOENT) {
+		inode = NULL;
+	} else {
+		/* must be a non-recoverable error */
+		inode = ERR_PTR(ret);
+	}
+
+	op_release(new_op);
+	return d_splice_alias(inode, dentry);
+}
+
+/* return 0 on success; non-zero otherwise */
+static int orangefs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
+	struct orangefs_kernel_op_s *new_op;
+	struct iattr iattr;
+	int ret;
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: called on %pd\n"
+		     "  (inode %pU): Parent is %pU | fs_id %d\n",
+		     __func__,
+		     dentry,
+		     get_khandle_from_ino(inode),
+		     &parent->refn.khandle,
+		     parent->refn.fs_id);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_REMOVE);
+	if (!new_op)
+		return -ENOMEM;
+
+	new_op->upcall.req.remove.parent_refn = parent->refn;
+	strncpy(new_op->upcall.req.remove.d_name, dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+
+	ret = service_operation(new_op, "orangefs_unlink",
+				get_interruptible_flag(inode));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "%s: service_operation returned:%d:\n",
+		     __func__,
+		     ret);
+
+	op_release(new_op);
+
+	if (!ret) {
+		drop_nlink(inode);
+
+		memset(&iattr, 0, sizeof iattr);
+		iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
+		iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
+		__orangefs_setattr(dir, &iattr);
+	}
+	return ret;
+}
+
+static int orangefs_symlink(struct user_namespace *mnt_userns,
+		         struct inode *dir,
+			 struct dentry *dentry,
+			 const char *symname)
+{
+	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
+	struct orangefs_kernel_op_s *new_op;
+	struct orangefs_object_kref ref;
+	struct inode *inode;
+	struct iattr iattr;
+	int mode = 0755;
+	int ret;
+
+	gossip_debug(GOSSIP_NAME_DEBUG, "%s: called\n", __func__);
+
+	if (!symname)
+		return -EINVAL;
+
+	if (strlen(symname)+1 > ORANGEFS_NAME_MAX)
+		return -ENAMETOOLONG;
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_SYMLINK);
+	if (!new_op)
+		return -ENOMEM;
+
+	new_op->upcall.req.sym.parent_refn = parent->refn;
+
+	fill_default_sys_attrs(new_op->upcall.req.sym.attributes,
+			       ORANGEFS_TYPE_SYMLINK,
+			       mode);
+
+	strncpy(new_op->upcall.req.sym.entry_name,
+		dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+	strncpy(new_op->upcall.req.sym.target, symname, ORANGEFS_NAME_MAX - 1);
+
+	ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Symlink Got ORANGEFS handle %pU on fsid %d (ret=%d)\n",
+		     &new_op->downcall.resp.sym.refn.khandle,
+		     new_op->downcall.resp.sym.refn.fs_id, ret);
+
+	if (ret < 0) {
+		gossip_debug(GOSSIP_NAME_DEBUG,
+			    "%s: failed with error code %d\n",
+			    __func__, ret);
+		goto out;
+	}
+
+	ref = new_op->downcall.resp.sym.refn;
+
+	inode = orangefs_new_inode(dir->i_sb, dir, S_IFLNK | mode, 0, &ref);
+	if (IS_ERR(inode)) {
+		gossip_err
+		    ("*** Failed to allocate orangefs symlink inode\n");
+		ret = PTR_ERR(inode);
+		goto out;
+	}
+	/*
+	 * This is necessary because orangefs_inode_getattr will not
+	 * re-read symlink size as it is impossible for it to change.
+	 * Invalidating the cache does not help.  orangefs_new_inode
+	 * does not set the correct size (it does not know symname).
+	 */
+	inode->i_size = strlen(symname);
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Assigned symlink inode new number of %pU\n",
+		     get_khandle_from_ino(inode));
+
+	d_instantiate_new(dentry, inode);
+	orangefs_set_timeout(dentry);
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Inode (Symlink) %pU -> %pd\n",
+		     get_khandle_from_ino(inode),
+		     dentry);
+
+	memset(&iattr, 0, sizeof iattr);
+	iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
+	iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
+	__orangefs_setattr(dir, &iattr);
+	ret = 0;
+out:
+	op_release(new_op);
+	return ret;
+}
+
+static int orangefs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+			  struct dentry *dentry, umode_t mode)
+{
+	struct orangefs_inode_s *parent = ORANGEFS_I(dir);
+	struct orangefs_kernel_op_s *new_op;
+	struct orangefs_object_kref ref;
+	struct inode *inode;
+	struct iattr iattr;
+	int ret;
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_MKDIR);
+	if (!new_op)
+		return -ENOMEM;
+
+	new_op->upcall.req.mkdir.parent_refn = parent->refn;
+
+	fill_default_sys_attrs(new_op->upcall.req.mkdir.attributes,
+			      ORANGEFS_TYPE_DIRECTORY, mode);
+
+	strncpy(new_op->upcall.req.mkdir.d_name,
+		dentry->d_name.name, ORANGEFS_NAME_MAX - 1);
+
+	ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Mkdir Got ORANGEFS handle %pU on fsid %d\n",
+		     &new_op->downcall.resp.mkdir.refn.khandle,
+		     new_op->downcall.resp.mkdir.refn.fs_id);
+
+	if (ret < 0) {
+		gossip_debug(GOSSIP_NAME_DEBUG,
+			     "%s: failed with error code %d\n",
+			     __func__, ret);
+		goto out;
+	}
+
+	ref = new_op->downcall.resp.mkdir.refn;
+
+	inode = orangefs_new_inode(dir->i_sb, dir, S_IFDIR | mode, 0, &ref);
+	if (IS_ERR(inode)) {
+		gossip_err("*** Failed to allocate orangefs dir inode\n");
+		ret = PTR_ERR(inode);
+		goto out;
+	}
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Assigned dir inode new number of %pU\n",
+		     get_khandle_from_ino(inode));
+
+	d_instantiate_new(dentry, inode);
+	orangefs_set_timeout(dentry);
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "Inode (Directory) %pU -> %pd\n",
+		     get_khandle_from_ino(inode),
+		     dentry);
+
+	/*
+	 * NOTE: we have no good way to keep nlink consistent for directories
+	 * across clients; keep constant at 1.
+	 */
+	memset(&iattr, 0, sizeof iattr);
+	iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
+	iattr.ia_mtime = iattr.ia_ctime = current_time(dir);
+	__orangefs_setattr(dir, &iattr);
+out:
+	op_release(new_op);
+	return ret;
+}
+
+static int orangefs_rename(struct user_namespace *mnt_userns,
+			struct inode *old_dir,
+			struct dentry *old_dentry,
+			struct inode *new_dir,
+			struct dentry *new_dentry,
+			unsigned int flags)
+{
+	struct orangefs_kernel_op_s *new_op;
+	struct iattr iattr;
+	int ret;
+
+	if (flags)
+		return -EINVAL;
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "orangefs_rename: called (%pd2 => %pd2) ct=%d\n",
+		     old_dentry, new_dentry, d_count(new_dentry));
+
+	memset(&iattr, 0, sizeof iattr);
+	iattr.ia_valid |= ATTR_MTIME | ATTR_CTIME;
+	iattr.ia_mtime = iattr.ia_ctime = current_time(new_dir);
+	__orangefs_setattr(new_dir, &iattr);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_RENAME);
+	if (!new_op)
+		return -EINVAL;
+
+	new_op->upcall.req.rename.old_parent_refn = ORANGEFS_I(old_dir)->refn;
+	new_op->upcall.req.rename.new_parent_refn = ORANGEFS_I(new_dir)->refn;
+
+	strncpy(new_op->upcall.req.rename.d_old_name,
+		old_dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+	strncpy(new_op->upcall.req.rename.d_new_name,
+		new_dentry->d_name.name,
+		ORANGEFS_NAME_MAX - 1);
+
+	ret = service_operation(new_op,
+				"orangefs_rename",
+				get_interruptible_flag(old_dentry->d_inode));
+
+	gossip_debug(GOSSIP_NAME_DEBUG,
+		     "orangefs_rename: got downcall status %d\n",
+		     ret);
+
+	if (new_dentry->d_inode)
+		new_dentry->d_inode->i_ctime = current_time(new_dentry->d_inode);
+
+	op_release(new_op);
+	return ret;
+}
+
+/* ORANGEFS implementation of VFS inode operations for directories */
+const struct inode_operations orangefs_dir_inode_operations = {
+	.lookup = orangefs_lookup,
+	.get_acl = orangefs_get_acl,
+	.set_acl = orangefs_set_acl,
+	.create = orangefs_create,
+	.unlink = orangefs_unlink,
+	.symlink = orangefs_symlink,
+	.mkdir = orangefs_mkdir,
+	.rmdir = orangefs_unlink,
+	.rename = orangefs_rename,
+	.setattr = orangefs_setattr,
+	.getattr = orangefs_getattr,
+	.listxattr = orangefs_listxattr,
+	.permission = orangefs_permission,
+	.update_time = orangefs_update_time,
+};
diff --git a/fs/orangefs/orangefs-bufmap.c b/fs/orangefs/orangefs-bufmap.c
new file mode 100644
index 000000000..b501dc07f
--- /dev/null
+++ b/fs/orangefs/orangefs-bufmap.c
@@ -0,0 +1,549 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+struct slot_map {
+	int c;
+	wait_queue_head_t q;
+	int count;
+	unsigned long *map;
+};
+
+static struct slot_map rw_map = {
+	.c = -1,
+	.q = __WAIT_QUEUE_HEAD_INITIALIZER(rw_map.q)
+};
+static struct slot_map readdir_map = {
+	.c = -1,
+	.q = __WAIT_QUEUE_HEAD_INITIALIZER(readdir_map.q)
+};
+
+
+static void install(struct slot_map *m, int count, unsigned long *map)
+{
+	spin_lock(&m->q.lock);
+	m->c = m->count = count;
+	m->map = map;
+	wake_up_all_locked(&m->q);
+	spin_unlock(&m->q.lock);
+}
+
+static void mark_killed(struct slot_map *m)
+{
+	spin_lock(&m->q.lock);
+	m->c -= m->count + 1;
+	spin_unlock(&m->q.lock);
+}
+
+static void run_down(struct slot_map *m)
+{
+	DEFINE_WAIT(wait);
+	spin_lock(&m->q.lock);
+	if (m->c != -1) {
+		for (;;) {
+			if (likely(list_empty(&wait.entry)))
+				__add_wait_queue_entry_tail(&m->q, &wait);
+			set_current_state(TASK_UNINTERRUPTIBLE);
+
+			if (m->c == -1)
+				break;
+
+			spin_unlock(&m->q.lock);
+			schedule();
+			spin_lock(&m->q.lock);
+		}
+		__remove_wait_queue(&m->q, &wait);
+		__set_current_state(TASK_RUNNING);
+	}
+	m->map = NULL;
+	spin_unlock(&m->q.lock);
+}
+
+static void put(struct slot_map *m, int slot)
+{
+	int v;
+	spin_lock(&m->q.lock);
+	__clear_bit(slot, m->map);
+	v = ++m->c;
+	if (v > 0)
+		wake_up_locked(&m->q);
+	if (unlikely(v == -1))     /* finished dying */
+		wake_up_all_locked(&m->q);
+	spin_unlock(&m->q.lock);
+}
+
+static int wait_for_free(struct slot_map *m)
+{
+	long left = slot_timeout_secs * HZ;
+	DEFINE_WAIT(wait);
+
+	do {
+		long n = left, t;
+		if (likely(list_empty(&wait.entry)))
+			__add_wait_queue_entry_tail_exclusive(&m->q, &wait);
+		set_current_state(TASK_INTERRUPTIBLE);
+
+		if (m->c > 0)
+			break;
+
+		if (m->c < 0) {
+			/* we are waiting for map to be installed */
+			/* it would better be there soon, or we go away */
+			if (n > ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ)
+				n = ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ;
+		}
+		spin_unlock(&m->q.lock);
+		t = schedule_timeout(n);
+		spin_lock(&m->q.lock);
+		if (unlikely(!t) && n != left && m->c < 0)
+			left = t;
+		else
+			left = t + (left - n);
+		if (signal_pending(current))
+			left = -EINTR;
+	} while (left > 0);
+
+	if (!list_empty(&wait.entry))
+		list_del(&wait.entry);
+	else if (left <= 0 && waitqueue_active(&m->q))
+		__wake_up_locked_key(&m->q, TASK_INTERRUPTIBLE, NULL);
+	__set_current_state(TASK_RUNNING);
+
+	if (likely(left > 0))
+		return 0;
+
+	return left < 0 ? -EINTR : -ETIMEDOUT;
+}
+
+static int get(struct slot_map *m)
+{
+	int res = 0;
+	spin_lock(&m->q.lock);
+	if (unlikely(m->c <= 0))
+		res = wait_for_free(m);
+	if (likely(!res)) {
+		m->c--;
+		res = find_first_zero_bit(m->map, m->count);
+		__set_bit(res, m->map);
+	}
+	spin_unlock(&m->q.lock);
+	return res;
+}
+
+/* used to describe mapped buffers */
+struct orangefs_bufmap_desc {
+	void __user *uaddr;		/* user space address pointer */
+	struct page **page_array;	/* array of mapped pages */
+	int array_count;		/* size of above arrays */
+	struct list_head list_link;
+};
+
+static struct orangefs_bufmap {
+	int desc_size;
+	int desc_shift;
+	int desc_count;
+	int total_size;
+	int page_count;
+
+	struct page **page_array;
+	struct orangefs_bufmap_desc *desc_array;
+
+	/* array to track usage of buffer descriptors */
+	unsigned long *buffer_index_array;
+
+	/* array to track usage of buffer descriptors for readdir */
+#define N DIV_ROUND_UP(ORANGEFS_READDIR_DEFAULT_DESC_COUNT, BITS_PER_LONG)
+	unsigned long readdir_index_array[N];
+#undef N
+} *__orangefs_bufmap;
+
+static DEFINE_SPINLOCK(orangefs_bufmap_lock);
+
+static void
+orangefs_bufmap_unmap(struct orangefs_bufmap *bufmap)
+{
+	unpin_user_pages(bufmap->page_array, bufmap->page_count);
+}
+
+static void
+orangefs_bufmap_free(struct orangefs_bufmap *bufmap)
+{
+	kfree(bufmap->page_array);
+	kfree(bufmap->desc_array);
+	bitmap_free(bufmap->buffer_index_array);
+	kfree(bufmap);
+}
+
+/*
+ * XXX: Can the size and shift change while the caller gives up the
+ * XXX: lock between calling this and doing something useful?
+ */
+
+int orangefs_bufmap_size_query(void)
+{
+	struct orangefs_bufmap *bufmap;
+	int size = 0;
+	spin_lock(&orangefs_bufmap_lock);
+	bufmap = __orangefs_bufmap;
+	if (bufmap)
+		size = bufmap->desc_size;
+	spin_unlock(&orangefs_bufmap_lock);
+	return size;
+}
+
+int orangefs_bufmap_shift_query(void)
+{
+	struct orangefs_bufmap *bufmap;
+	int shift = 0;
+	spin_lock(&orangefs_bufmap_lock);
+	bufmap = __orangefs_bufmap;
+	if (bufmap)
+		shift = bufmap->desc_shift;
+	spin_unlock(&orangefs_bufmap_lock);
+	return shift;
+}
+
+static DECLARE_WAIT_QUEUE_HEAD(bufmap_waitq);
+static DECLARE_WAIT_QUEUE_HEAD(readdir_waitq);
+
+static struct orangefs_bufmap *
+orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc)
+{
+	struct orangefs_bufmap *bufmap;
+
+	bufmap = kzalloc(sizeof(*bufmap), GFP_KERNEL);
+	if (!bufmap)
+		goto out;
+
+	bufmap->total_size = user_desc->total_size;
+	bufmap->desc_count = user_desc->count;
+	bufmap->desc_size = user_desc->size;
+	bufmap->desc_shift = ilog2(bufmap->desc_size);
+
+	bufmap->buffer_index_array = bitmap_zalloc(bufmap->desc_count, GFP_KERNEL);
+	if (!bufmap->buffer_index_array)
+		goto out_free_bufmap;
+
+	bufmap->desc_array =
+		kcalloc(bufmap->desc_count, sizeof(struct orangefs_bufmap_desc),
+			GFP_KERNEL);
+	if (!bufmap->desc_array)
+		goto out_free_index_array;
+
+	bufmap->page_count = bufmap->total_size / PAGE_SIZE;
+
+	/* allocate storage to track our page mappings */
+	bufmap->page_array =
+		kcalloc(bufmap->page_count, sizeof(struct page *), GFP_KERNEL);
+	if (!bufmap->page_array)
+		goto out_free_desc_array;
+
+	return bufmap;
+
+out_free_desc_array:
+	kfree(bufmap->desc_array);
+out_free_index_array:
+	bitmap_free(bufmap->buffer_index_array);
+out_free_bufmap:
+	kfree(bufmap);
+out:
+	return NULL;
+}
+
+static int
+orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
+		struct ORANGEFS_dev_map_desc *user_desc)
+{
+	int pages_per_desc = bufmap->desc_size / PAGE_SIZE;
+	int offset = 0, ret, i;
+
+	/* map the pages */
+	ret = pin_user_pages_fast((unsigned long)user_desc->ptr,
+			     bufmap->page_count, FOLL_WRITE, bufmap->page_array);
+
+	if (ret < 0)
+		return ret;
+
+	if (ret != bufmap->page_count) {
+		gossip_err("orangefs error: asked for %d pages, only got %d.\n",
+				bufmap->page_count, ret);
+
+		for (i = 0; i < ret; i++) {
+			SetPageError(bufmap->page_array[i]);
+			unpin_user_page(bufmap->page_array[i]);
+		}
+		return -ENOMEM;
+	}
+
+	/*
+	 * ideally we want to get kernel space pointers for each page, but
+	 * we can't kmap that many pages at once if highmem is being used.
+	 * so instead, we just kmap/kunmap the page address each time the
+	 * kaddr is needed.
+	 */
+	for (i = 0; i < bufmap->page_count; i++)
+		flush_dcache_page(bufmap->page_array[i]);
+
+	/* build a list of available descriptors */
+	for (offset = 0, i = 0; i < bufmap->desc_count; i++) {
+		bufmap->desc_array[i].page_array = &bufmap->page_array[offset];
+		bufmap->desc_array[i].array_count = pages_per_desc;
+		bufmap->desc_array[i].uaddr =
+		    (user_desc->ptr + (i * pages_per_desc * PAGE_SIZE));
+		offset += pages_per_desc;
+	}
+
+	return 0;
+}
+
+/*
+ * orangefs_bufmap_initialize()
+ *
+ * initializes the mapped buffer interface
+ *
+ * returns 0 on success, -errno on failure
+ */
+int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc)
+{
+	struct orangefs_bufmap *bufmap;
+	int ret = -EINVAL;
+
+	gossip_debug(GOSSIP_BUFMAP_DEBUG,
+		     "orangefs_bufmap_initialize: called (ptr ("
+		     "%p) sz (%d) cnt(%d).\n",
+		     user_desc->ptr,
+		     user_desc->size,
+		     user_desc->count);
+
+	if (user_desc->total_size < 0 ||
+	    user_desc->size < 0 ||
+	    user_desc->count < 0)
+		goto out;
+
+	/*
+	 * sanity check alignment and size of buffer that caller wants to
+	 * work with
+	 */
+	if (PAGE_ALIGN((unsigned long)user_desc->ptr) !=
+	    (unsigned long)user_desc->ptr) {
+		gossip_err("orangefs error: memory alignment (front). %p\n",
+			   user_desc->ptr);
+		goto out;
+	}
+
+	if (PAGE_ALIGN(((unsigned long)user_desc->ptr + user_desc->total_size))
+	    != (unsigned long)(user_desc->ptr + user_desc->total_size)) {
+		gossip_err("orangefs error: memory alignment (back).(%p + %d)\n",
+			   user_desc->ptr,
+			   user_desc->total_size);
+		goto out;
+	}
+
+	if (user_desc->total_size != (user_desc->size * user_desc->count)) {
+		gossip_err("orangefs error: user provided an oddly sized buffer: (%d, %d, %d)\n",
+			   user_desc->total_size,
+			   user_desc->size,
+			   user_desc->count);
+		goto out;
+	}
+
+	if ((user_desc->size % PAGE_SIZE) != 0) {
+		gossip_err("orangefs error: bufmap size not page size divisible (%d).\n",
+			   user_desc->size);
+		goto out;
+	}
+
+	ret = -ENOMEM;
+	bufmap = orangefs_bufmap_alloc(user_desc);
+	if (!bufmap)
+		goto out;
+
+	ret = orangefs_bufmap_map(bufmap, user_desc);
+	if (ret)
+		goto out_free_bufmap;
+
+
+	spin_lock(&orangefs_bufmap_lock);
+	if (__orangefs_bufmap) {
+		spin_unlock(&orangefs_bufmap_lock);
+		gossip_err("orangefs: error: bufmap already initialized.\n");
+		ret = -EINVAL;
+		goto out_unmap_bufmap;
+	}
+	__orangefs_bufmap = bufmap;
+	install(&rw_map,
+		bufmap->desc_count,
+		bufmap->buffer_index_array);
+	install(&readdir_map,
+		ORANGEFS_READDIR_DEFAULT_DESC_COUNT,
+		bufmap->readdir_index_array);
+	spin_unlock(&orangefs_bufmap_lock);
+
+	gossip_debug(GOSSIP_BUFMAP_DEBUG,
+		     "orangefs_bufmap_initialize: exiting normally\n");
+	return 0;
+
+out_unmap_bufmap:
+	orangefs_bufmap_unmap(bufmap);
+out_free_bufmap:
+	orangefs_bufmap_free(bufmap);
+out:
+	return ret;
+}
+
+/*
+ * orangefs_bufmap_finalize()
+ *
+ * shuts down the mapped buffer interface and releases any resources
+ * associated with it
+ *
+ * no return value
+ */
+void orangefs_bufmap_finalize(void)
+{
+	struct orangefs_bufmap *bufmap = __orangefs_bufmap;
+	if (!bufmap)
+		return;
+	gossip_debug(GOSSIP_BUFMAP_DEBUG, "orangefs_bufmap_finalize: called\n");
+	mark_killed(&rw_map);
+	mark_killed(&readdir_map);
+	gossip_debug(GOSSIP_BUFMAP_DEBUG,
+		     "orangefs_bufmap_finalize: exiting normally\n");
+}
+
+void orangefs_bufmap_run_down(void)
+{
+	struct orangefs_bufmap *bufmap = __orangefs_bufmap;
+	if (!bufmap)
+		return;
+	run_down(&rw_map);
+	run_down(&readdir_map);
+	spin_lock(&orangefs_bufmap_lock);
+	__orangefs_bufmap = NULL;
+	spin_unlock(&orangefs_bufmap_lock);
+	orangefs_bufmap_unmap(bufmap);
+	orangefs_bufmap_free(bufmap);
+}
+
+/*
+ * orangefs_bufmap_get()
+ *
+ * gets a free mapped buffer descriptor, will sleep until one becomes
+ * available if necessary
+ *
+ * returns slot on success, -errno on failure
+ */
+int orangefs_bufmap_get(void)
+{
+	return get(&rw_map);
+}
+
+/*
+ * orangefs_bufmap_put()
+ *
+ * returns a mapped buffer descriptor to the collection
+ *
+ * no return value
+ */
+void orangefs_bufmap_put(int buffer_index)
+{
+	put(&rw_map, buffer_index);
+}
+
+/*
+ * orangefs_readdir_index_get()
+ *
+ * gets a free descriptor, will sleep until one becomes
+ * available if necessary.
+ * Although the readdir buffers are not mapped into kernel space
+ * we could do that at a later point of time. Regardless, these
+ * indices are used by the client-core.
+ *
+ * returns slot on success, -errno on failure
+ */
+int orangefs_readdir_index_get(void)
+{
+	return get(&readdir_map);
+}
+
+void orangefs_readdir_index_put(int buffer_index)
+{
+	put(&readdir_map, buffer_index);
+}
+
+/*
+ * we've been handed an iovec, we need to copy it to
+ * the shared memory descriptor at "buffer_index".
+ */
+int orangefs_bufmap_copy_from_iovec(struct iov_iter *iter,
+				int buffer_index,
+				size_t size)
+{
+	struct orangefs_bufmap_desc *to;
+	int i;
+
+	gossip_debug(GOSSIP_BUFMAP_DEBUG,
+		     "%s: buffer_index:%d: size:%zu:\n",
+		     __func__, buffer_index, size);
+
+	to = &__orangefs_bufmap->desc_array[buffer_index];
+	for (i = 0; size; i++) {
+		struct page *page = to->page_array[i];
+		size_t n = size;
+		if (n > PAGE_SIZE)
+			n = PAGE_SIZE;
+		if (copy_page_from_iter(page, 0, n, iter) != n)
+			return -EFAULT;
+		size -= n;
+	}
+	return 0;
+}
+
+/*
+ * we've been handed an iovec, we need to fill it from
+ * the shared memory descriptor at "buffer_index".
+ */
+int orangefs_bufmap_copy_to_iovec(struct iov_iter *iter,
+				    int buffer_index,
+				    size_t size)
+{
+	struct orangefs_bufmap_desc *from;
+	int i;
+
+	from = &__orangefs_bufmap->desc_array[buffer_index];
+	gossip_debug(GOSSIP_BUFMAP_DEBUG,
+		     "%s: buffer_index:%d: size:%zu:\n",
+		     __func__, buffer_index, size);
+
+
+	for (i = 0; size; i++) {
+		struct page *page = from->page_array[i];
+		size_t n = size;
+		if (n > PAGE_SIZE)
+			n = PAGE_SIZE;
+		n = copy_page_to_iter(page, 0, n, iter);
+		if (!n)
+			return -EFAULT;
+		size -= n;
+	}
+	return 0;
+}
+
+void orangefs_bufmap_page_fill(void *page_to,
+				int buffer_index,
+				int slot_index)
+{
+	struct orangefs_bufmap_desc *from;
+	void *page_from;
+
+	from = &__orangefs_bufmap->desc_array[buffer_index];
+	page_from = kmap_atomic(from->page_array[slot_index]);
+	memcpy(page_to, page_from, PAGE_SIZE);
+	kunmap_atomic(page_from);
+}
diff --git a/fs/orangefs/orangefs-bufmap.h b/fs/orangefs/orangefs-bufmap.h
new file mode 100644
index 000000000..75b2d2833
--- /dev/null
+++ b/fs/orangefs/orangefs-bufmap.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#ifndef __ORANGEFS_BUFMAP_H
+#define __ORANGEFS_BUFMAP_H
+
+int orangefs_bufmap_size_query(void);
+
+int orangefs_bufmap_shift_query(void);
+
+int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc);
+
+void orangefs_bufmap_finalize(void);
+
+void orangefs_bufmap_run_down(void);
+
+int orangefs_bufmap_get(void);
+
+void orangefs_bufmap_put(int buffer_index);
+
+int orangefs_readdir_index_get(void);
+
+void orangefs_readdir_index_put(int buffer_index);
+
+int orangefs_bufmap_copy_from_iovec(struct iov_iter *iter,
+				int buffer_index,
+				size_t size);
+
+int orangefs_bufmap_copy_to_iovec(struct iov_iter *iter,
+			      int buffer_index,
+			      size_t size);
+
+void orangefs_bufmap_page_fill(void *kaddr, int buffer_index, int slot_index);
+
+#endif /* __ORANGEFS_BUFMAP_H */
diff --git a/fs/orangefs/orangefs-cache.c b/fs/orangefs/orangefs-cache.c
new file mode 100644
index 000000000..3b6982bf6
--- /dev/null
+++ b/fs/orangefs/orangefs-cache.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+
+/* tags assigned to kernel upcall operations */
+static __u64 next_tag_value;
+static DEFINE_SPINLOCK(next_tag_value_lock);
+
+/* the orangefs memory caches */
+
+/* a cache for orangefs upcall/downcall operations */
+static struct kmem_cache *op_cache;
+
+int op_cache_initialize(void)
+{
+	op_cache = kmem_cache_create("orangefs_op_cache",
+				     sizeof(struct orangefs_kernel_op_s),
+				     0,
+				     ORANGEFS_CACHE_CREATE_FLAGS,
+				     NULL);
+
+	if (!op_cache) {
+		gossip_err("Cannot create orangefs_op_cache\n");
+		return -ENOMEM;
+	}
+
+	/* initialize our atomic tag counter */
+	spin_lock(&next_tag_value_lock);
+	next_tag_value = 100;
+	spin_unlock(&next_tag_value_lock);
+	return 0;
+}
+
+int op_cache_finalize(void)
+{
+	kmem_cache_destroy(op_cache);
+	return 0;
+}
+
+char *get_opname_string(struct orangefs_kernel_op_s *new_op)
+{
+	if (new_op) {
+		__s32 type = new_op->upcall.type;
+
+		if (type == ORANGEFS_VFS_OP_FILE_IO)
+			return "OP_FILE_IO";
+		else if (type == ORANGEFS_VFS_OP_LOOKUP)
+			return "OP_LOOKUP";
+		else if (type == ORANGEFS_VFS_OP_CREATE)
+			return "OP_CREATE";
+		else if (type == ORANGEFS_VFS_OP_GETATTR)
+			return "OP_GETATTR";
+		else if (type == ORANGEFS_VFS_OP_REMOVE)
+			return "OP_REMOVE";
+		else if (type == ORANGEFS_VFS_OP_MKDIR)
+			return "OP_MKDIR";
+		else if (type == ORANGEFS_VFS_OP_READDIR)
+			return "OP_READDIR";
+		else if (type == ORANGEFS_VFS_OP_READDIRPLUS)
+			return "OP_READDIRPLUS";
+		else if (type == ORANGEFS_VFS_OP_SETATTR)
+			return "OP_SETATTR";
+		else if (type == ORANGEFS_VFS_OP_SYMLINK)
+			return "OP_SYMLINK";
+		else if (type == ORANGEFS_VFS_OP_RENAME)
+			return "OP_RENAME";
+		else if (type == ORANGEFS_VFS_OP_STATFS)
+			return "OP_STATFS";
+		else if (type == ORANGEFS_VFS_OP_TRUNCATE)
+			return "OP_TRUNCATE";
+		else if (type == ORANGEFS_VFS_OP_RA_FLUSH)
+			return "OP_RA_FLUSH";
+		else if (type == ORANGEFS_VFS_OP_FS_MOUNT)
+			return "OP_FS_MOUNT";
+		else if (type == ORANGEFS_VFS_OP_FS_UMOUNT)
+			return "OP_FS_UMOUNT";
+		else if (type == ORANGEFS_VFS_OP_GETXATTR)
+			return "OP_GETXATTR";
+		else if (type == ORANGEFS_VFS_OP_SETXATTR)
+			return "OP_SETXATTR";
+		else if (type == ORANGEFS_VFS_OP_LISTXATTR)
+			return "OP_LISTXATTR";
+		else if (type == ORANGEFS_VFS_OP_REMOVEXATTR)
+			return "OP_REMOVEXATTR";
+		else if (type == ORANGEFS_VFS_OP_PARAM)
+			return "OP_PARAM";
+		else if (type == ORANGEFS_VFS_OP_PERF_COUNT)
+			return "OP_PERF_COUNT";
+		else if (type == ORANGEFS_VFS_OP_CANCEL)
+			return "OP_CANCEL";
+		else if (type == ORANGEFS_VFS_OP_FSYNC)
+			return "OP_FSYNC";
+		else if (type == ORANGEFS_VFS_OP_FSKEY)
+			return "OP_FSKEY";
+		else if (type == ORANGEFS_VFS_OP_FEATURES)
+			return "OP_FEATURES";
+	}
+	return "OP_UNKNOWN?";
+}
+
+void orangefs_new_tag(struct orangefs_kernel_op_s *op)
+{
+	spin_lock(&next_tag_value_lock);
+	op->tag = next_tag_value++;
+	if (next_tag_value == 0)
+		next_tag_value = 100;
+	spin_unlock(&next_tag_value_lock);
+}
+
+struct orangefs_kernel_op_s *op_alloc(__s32 type)
+{
+	struct orangefs_kernel_op_s *new_op = NULL;
+
+	new_op = kmem_cache_zalloc(op_cache, GFP_KERNEL);
+	if (new_op) {
+		INIT_LIST_HEAD(&new_op->list);
+		spin_lock_init(&new_op->lock);
+		init_completion(&new_op->waitq);
+
+		new_op->upcall.type = ORANGEFS_VFS_OP_INVALID;
+		new_op->downcall.type = ORANGEFS_VFS_OP_INVALID;
+		new_op->downcall.status = -1;
+
+		new_op->op_state = OP_VFS_STATE_UNKNOWN;
+
+		/* initialize the op specific tag and upcall credentials */
+		orangefs_new_tag(new_op);
+		new_op->upcall.type = type;
+		new_op->attempts = 0;
+		gossip_debug(GOSSIP_CACHE_DEBUG,
+			     "Alloced OP (%p: %llu %s)\n",
+			     new_op,
+			     llu(new_op->tag),
+			     get_opname_string(new_op));
+
+		new_op->upcall.uid = from_kuid(&init_user_ns,
+					       current_fsuid());
+
+		new_op->upcall.gid = from_kgid(&init_user_ns,
+					       current_fsgid());
+	} else {
+		gossip_err("op_alloc: kmem_cache_zalloc failed!\n");
+	}
+	return new_op;
+}
+
+void op_release(struct orangefs_kernel_op_s *orangefs_op)
+{
+	if (orangefs_op) {
+		gossip_debug(GOSSIP_CACHE_DEBUG,
+			     "Releasing OP (%p: %llu)\n",
+			     orangefs_op,
+			     llu(orangefs_op->tag));
+		kmem_cache_free(op_cache, orangefs_op);
+	} else {
+		gossip_err("NULL pointer in op_release\n");
+	}
+}
diff --git a/fs/orangefs/orangefs-debug.h b/fs/orangefs/orangefs-debug.h
new file mode 100644
index 000000000..6e079d423
--- /dev/null
+++ b/fs/orangefs/orangefs-debug.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/* This file just defines debugging masks to be used with the gossip
+ * logging utility.  All debugging masks for ORANGEFS are kept here to make
+ * sure we don't have collisions.
+ */
+
+#ifndef __ORANGEFS_DEBUG_H
+#define __ORANGEFS_DEBUG_H
+
+#ifdef __KERNEL__
+#include <linux/types.h>
+#include <linux/kernel.h>
+#else
+#include <stdint.h>
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
+#define	GOSSIP_NO_DEBUG			(__u64)0
+
+#define GOSSIP_SUPER_DEBUG		((__u64)1 << 0)
+#define GOSSIP_INODE_DEBUG		((__u64)1 << 1)
+#define GOSSIP_FILE_DEBUG		((__u64)1 << 2)
+#define GOSSIP_DIR_DEBUG		((__u64)1 << 3)
+#define GOSSIP_UTILS_DEBUG		((__u64)1 << 4)
+#define GOSSIP_WAIT_DEBUG		((__u64)1 << 5)
+#define GOSSIP_ACL_DEBUG		((__u64)1 << 6)
+#define GOSSIP_DCACHE_DEBUG		((__u64)1 << 7)
+#define GOSSIP_DEV_DEBUG		((__u64)1 << 8)
+#define GOSSIP_NAME_DEBUG		((__u64)1 << 9)
+#define GOSSIP_BUFMAP_DEBUG		((__u64)1 << 10)
+#define GOSSIP_CACHE_DEBUG		((__u64)1 << 11)
+#define GOSSIP_DEBUGFS_DEBUG		((__u64)1 << 12)
+#define GOSSIP_XATTR_DEBUG		((__u64)1 << 13)
+#define GOSSIP_INIT_DEBUG		((__u64)1 << 14)
+#define GOSSIP_SYSFS_DEBUG		((__u64)1 << 15)
+
+#define GOSSIP_MAX_NR                 16
+#define GOSSIP_MAX_DEBUG              (((__u64)1 << GOSSIP_MAX_NR) - 1)
+
+/* a private internal type */
+struct __keyword_mask_s {
+	const char *keyword;
+	__u64 mask_val;
+};
+
+/*
+ * Map all kmod keywords to kmod debug masks here. Keep this
+ * structure "packed":
+ *
+ *   "all" is always last...
+ *
+ *   keyword     mask_val     index
+ *     foo          1           0
+ *     bar          2           1
+ *     baz          4           2
+ *     qux          8           3
+ *      .           .           .
+ */
+static struct __keyword_mask_s s_kmod_keyword_mask_map[] = {
+	{"super", GOSSIP_SUPER_DEBUG},
+	{"inode", GOSSIP_INODE_DEBUG},
+	{"file", GOSSIP_FILE_DEBUG},
+	{"dir", GOSSIP_DIR_DEBUG},
+	{"utils", GOSSIP_UTILS_DEBUG},
+	{"wait", GOSSIP_WAIT_DEBUG},
+	{"acl", GOSSIP_ACL_DEBUG},
+	{"dcache", GOSSIP_DCACHE_DEBUG},
+	{"dev", GOSSIP_DEV_DEBUG},
+	{"name", GOSSIP_NAME_DEBUG},
+	{"bufmap", GOSSIP_BUFMAP_DEBUG},
+	{"cache", GOSSIP_CACHE_DEBUG},
+	{"debugfs", GOSSIP_DEBUGFS_DEBUG},
+	{"xattr", GOSSIP_XATTR_DEBUG},
+	{"init", GOSSIP_INIT_DEBUG},
+	{"sysfs", GOSSIP_SYSFS_DEBUG},
+	{"none", GOSSIP_NO_DEBUG},
+	{"all", GOSSIP_MAX_DEBUG}
+};
+
+static const int num_kmod_keyword_mask_map = (int)
+	(ARRAY_SIZE(s_kmod_keyword_mask_map));
+
+#endif /* __ORANGEFS_DEBUG_H */
diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c
new file mode 100644
index 000000000..1b508f543
--- /dev/null
+++ b/fs/orangefs/orangefs-debugfs.c
@@ -0,0 +1,1010 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * What:		/sys/kernel/debug/orangefs/debug-help
+ * Date:		June 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			List of client and kernel debug keywords.
+ *
+ *
+ * What:		/sys/kernel/debug/orangefs/client-debug
+ * Date:		June 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Debug setting for "the client", the userspace
+ * 			helper for the kernel module.
+ *
+ *
+ * What:		/sys/kernel/debug/orangefs/kernel-debug
+ * Date:		June 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Debug setting for the orangefs kernel module.
+ *
+ * 			Any of the keywords, or comma-separated lists
+ * 			of keywords, from debug-help can be catted to
+ * 			client-debug or kernel-debug.
+ *
+ * 			"none", "all" and "verbose" are special keywords
+ * 			for client-debug. Setting client-debug to "all"
+ * 			is kind of like trying to drink water from a
+ * 			fire hose, "verbose" triggers most of the same
+ * 			output except for the constant flow of output
+ * 			from the main wait loop.
+ *
+ * 			"none" and "all" are similar settings for kernel-debug
+ * 			no need for a "verbose".
+ */
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+
+#include <linux/uaccess.h>
+
+#include "orangefs-debugfs.h"
+#include "protocol.h"
+#include "orangefs-kernel.h"
+
+#define DEBUG_HELP_STRING_SIZE 4096
+#define HELP_STRING_UNINITIALIZED \
+	"Client Debug Keywords are unknown until the first time\n" \
+	"the client is started after boot.\n"
+#define ORANGEFS_KMOD_DEBUG_HELP_FILE "debug-help"
+#define ORANGEFS_KMOD_DEBUG_FILE "kernel-debug"
+#define ORANGEFS_CLIENT_DEBUG_FILE "client-debug"
+#define ORANGEFS_VERBOSE "verbose"
+#define ORANGEFS_ALL "all"
+
+/*
+ * An array of client_debug_mask will be built to hold debug keyword/mask
+ * values fetched from userspace.
+ */
+struct client_debug_mask {
+	char *keyword;
+	__u64 mask1;
+	__u64 mask2;
+};
+
+static void orangefs_kernel_debug_init(void);
+
+static int orangefs_debug_help_open(struct inode *, struct file *);
+static void *help_start(struct seq_file *, loff_t *);
+static void *help_next(struct seq_file *, void *, loff_t *);
+static void help_stop(struct seq_file *, void *);
+static int help_show(struct seq_file *, void *);
+
+static int orangefs_debug_open(struct inode *, struct file *);
+
+static ssize_t orangefs_debug_read(struct file *,
+				 char __user *,
+				 size_t,
+				 loff_t *);
+
+static ssize_t orangefs_debug_write(struct file *,
+				  const char __user *,
+				  size_t,
+				  loff_t *);
+
+static int orangefs_prepare_cdm_array(char *);
+static void debug_mask_to_string(void *, int);
+static void do_k_string(void *, int);
+static void do_c_string(void *, int);
+static int keyword_is_amalgam(char *);
+static int check_amalgam_keyword(void *, int);
+static void debug_string_to_mask(char *, void *, int);
+static void do_c_mask(int, char *, struct client_debug_mask **);
+static void do_k_mask(int, char *, __u64 **);
+
+static char kernel_debug_string[ORANGEFS_MAX_DEBUG_STRING_LEN] = "none";
+static char *debug_help_string;
+static char client_debug_string[ORANGEFS_MAX_DEBUG_STRING_LEN];
+static char client_debug_array_string[ORANGEFS_MAX_DEBUG_STRING_LEN];
+
+static struct dentry *client_debug_dentry;
+static struct dentry *debug_dir;
+
+static unsigned int kernel_mask_set_mod_init;
+static int orangefs_debug_disabled = 1;
+static int help_string_initialized;
+
+static const struct seq_operations help_debug_ops = {
+	.start	= help_start,
+	.next	= help_next,
+	.stop	= help_stop,
+	.show	= help_show,
+};
+
+static const struct file_operations debug_help_fops = {
+	.owner		= THIS_MODULE,
+	.open           = orangefs_debug_help_open,
+	.read           = seq_read,
+	.release        = seq_release,
+	.llseek         = seq_lseek,
+};
+
+static const struct file_operations kernel_debug_fops = {
+	.owner		= THIS_MODULE,
+	.open           = orangefs_debug_open,
+	.read           = orangefs_debug_read,
+	.write		= orangefs_debug_write,
+	.llseek         = generic_file_llseek,
+};
+
+static int client_all_index;
+static int client_verbose_index;
+
+static struct client_debug_mask *cdm_array;
+static int cdm_element_count;
+
+static struct client_debug_mask client_debug_mask;
+
+/*
+ * Used to protect data in ORANGEFS_KMOD_DEBUG_FILE and
+ * ORANGEFS_KMOD_DEBUG_FILE.
+ */
+static DEFINE_MUTEX(orangefs_debug_lock);
+
+/* Used to protect data in ORANGEFS_KMOD_DEBUG_HELP_FILE */
+static DEFINE_MUTEX(orangefs_help_file_lock);
+
+/*
+ * initialize kmod debug operations, create orangefs debugfs dir and
+ * ORANGEFS_KMOD_DEBUG_HELP_FILE.
+ */
+void orangefs_debugfs_init(int debug_mask)
+{
+	/* convert input debug mask to a 64-bit unsigned integer */
+        orangefs_gossip_debug_mask = (unsigned long long)debug_mask;
+
+	/*
+	 * set the kernel's gossip debug string; invalid mask values will
+	 * be ignored.
+	 */
+	debug_mask_to_string(&orangefs_gossip_debug_mask, 0);
+
+	/* remove any invalid values from the mask */
+	debug_string_to_mask(kernel_debug_string, &orangefs_gossip_debug_mask,
+	    0);
+
+	/*
+	 * if the mask has a non-zero value, then indicate that the mask
+	 * was set when the kernel module was loaded.  The orangefs dev ioctl
+	 * command will look at this boolean to determine if the kernel's
+	 * debug mask should be overwritten when the client-core is started.
+	 */
+	if (orangefs_gossip_debug_mask != 0)
+		kernel_mask_set_mod_init = true;
+
+	pr_info("%s: called with debug mask: :%s: :%llx:\n",
+		__func__,
+		kernel_debug_string,
+		(unsigned long long)orangefs_gossip_debug_mask);
+
+	debug_dir = debugfs_create_dir("orangefs", NULL);
+
+	debugfs_create_file(ORANGEFS_KMOD_DEBUG_HELP_FILE, 0444, debug_dir,
+			    debug_help_string, &debug_help_fops);
+
+	orangefs_debug_disabled = 0;
+
+	orangefs_kernel_debug_init();
+}
+
+/*
+ * initialize the kernel-debug file.
+ */
+static void orangefs_kernel_debug_init(void)
+{
+	static char k_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);
+
+	if (strlen(kernel_debug_string) + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) {
+		strcpy(k_buffer, kernel_debug_string);
+		strcat(k_buffer, "\n");
+	} else {
+		strcpy(k_buffer, "none\n");
+		pr_info("%s: overflow 1!\n", __func__);
+	}
+
+	debugfs_create_file(ORANGEFS_KMOD_DEBUG_FILE, 0444, debug_dir, k_buffer,
+			    &kernel_debug_fops);
+}
+
+
+void orangefs_debugfs_cleanup(void)
+{
+	debugfs_remove_recursive(debug_dir);
+	kfree(debug_help_string);
+	debug_help_string = NULL;
+}
+
+/* open ORANGEFS_KMOD_DEBUG_HELP_FILE */
+static int orangefs_debug_help_open(struct inode *inode, struct file *file)
+{
+	int rc = -ENODEV;
+	int ret;
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "orangefs_debug_help_open: start\n");
+
+	if (orangefs_debug_disabled)
+		goto out;
+
+	ret = seq_open(file, &help_debug_ops);
+	if (ret)
+		goto out;
+
+	((struct seq_file *)(file->private_data))->private = inode->i_private;
+
+	rc = 0;
+
+out:
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "orangefs_debug_help_open: rc:%d:\n",
+		     rc);
+	return rc;
+}
+
+/*
+ * I think start always gets called again after stop. Start
+ * needs to return NULL when it is done. The whole "payload"
+ * in this case is a single (long) string, so by the second
+ * time we get to start (pos = 1), we're done.
+ */
+static void *help_start(struct seq_file *m, loff_t *pos)
+{
+	void *payload = NULL;
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "help_start: start\n");
+
+	mutex_lock(&orangefs_help_file_lock);
+
+	if (*pos == 0)
+		payload = m->private;
+
+	return payload;
+}
+
+static void *help_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	(*pos)++;
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "help_next: start\n");
+
+	return NULL;
+}
+
+static void help_stop(struct seq_file *m, void *p)
+{
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "help_stop: start\n");
+	mutex_unlock(&orangefs_help_file_lock);
+}
+
+static int help_show(struct seq_file *m, void *v)
+{
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "help_show: start\n");
+
+	seq_puts(m, v);
+
+	return 0;
+}
+
+/*
+ * initialize the client-debug file.
+ */
+static void orangefs_client_debug_init(void)
+{
+
+	static char c_buffer[ORANGEFS_MAX_DEBUG_STRING_LEN] = { };
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "%s: start\n", __func__);
+
+	if (strlen(client_debug_string) + 1 < ORANGEFS_MAX_DEBUG_STRING_LEN) {
+		strcpy(c_buffer, client_debug_string);
+		strcat(c_buffer, "\n");
+	} else {
+		strcpy(c_buffer, "none\n");
+		pr_info("%s: overflow! 2\n", __func__);
+	}
+
+	client_debug_dentry = debugfs_create_file(ORANGEFS_CLIENT_DEBUG_FILE,
+						  0444,
+						  debug_dir,
+						  c_buffer,
+						  &kernel_debug_fops);
+}
+
+/* open ORANGEFS_KMOD_DEBUG_FILE or ORANGEFS_CLIENT_DEBUG_FILE.*/
+static int orangefs_debug_open(struct inode *inode, struct file *file)
+{
+	int rc = -ENODEV;
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "%s: orangefs_debug_disabled: %d\n",
+		     __func__,
+		     orangefs_debug_disabled);
+
+	if (orangefs_debug_disabled)
+		goto out;
+
+	rc = 0;
+	mutex_lock(&orangefs_debug_lock);
+	file->private_data = inode->i_private;
+	mutex_unlock(&orangefs_debug_lock);
+
+out:
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "orangefs_debug_open: rc: %d\n",
+		     rc);
+	return rc;
+}
+
+static ssize_t orangefs_debug_read(struct file *file,
+				 char __user *ubuf,
+				 size_t count,
+				 loff_t *ppos)
+{
+	char *buf;
+	int sprintf_ret;
+	ssize_t read_ret = -ENOMEM;
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG, "orangefs_debug_read: start\n");
+
+	buf = kmalloc(ORANGEFS_MAX_DEBUG_STRING_LEN, GFP_KERNEL);
+	if (!buf)
+		goto out;
+
+	mutex_lock(&orangefs_debug_lock);
+	sprintf_ret = sprintf(buf, "%s", (char *)file->private_data);
+	mutex_unlock(&orangefs_debug_lock);
+
+	read_ret = simple_read_from_buffer(ubuf, count, ppos, buf, sprintf_ret);
+
+	kfree(buf);
+
+out:
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "orangefs_debug_read: ret: %zu\n",
+		     read_ret);
+
+	return read_ret;
+}
+
+static ssize_t orangefs_debug_write(struct file *file,
+				  const char __user *ubuf,
+				  size_t count,
+				  loff_t *ppos)
+{
+	char *buf;
+	int rc = -EFAULT;
+	size_t silly = 0;
+	char *debug_string;
+	struct orangefs_kernel_op_s *new_op = NULL;
+	struct client_debug_mask c_mask = { NULL, 0, 0 };
+	char *s;
+
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		"orangefs_debug_write: %pD\n",
+		file);
+
+	if (count == 0)
+		return 0;
+
+	/*
+	 * Thwart users who try to jamb a ridiculous number
+	 * of bytes into the debug file...
+	 */
+	if (count > ORANGEFS_MAX_DEBUG_STRING_LEN + 1) {
+		silly = count;
+		count = ORANGEFS_MAX_DEBUG_STRING_LEN + 1;
+	}
+
+	buf = kzalloc(ORANGEFS_MAX_DEBUG_STRING_LEN, GFP_KERNEL);
+	if (!buf)
+		goto out;
+
+	if (copy_from_user(buf, ubuf, count - 1)) {
+		gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+			     "%s: copy_from_user failed!\n",
+			     __func__);
+		goto out;
+	}
+
+	/*
+	 * Map the keyword string from userspace into a valid debug mask.
+	 * The mapping process involves mapping the human-inputted string
+	 * into a valid mask, and then rebuilding the string from the
+	 * verified valid mask.
+	 *
+	 * A service operation is required to set a new client-side
+	 * debug mask.
+	 */
+	if (!strcmp(file->f_path.dentry->d_name.name,
+		    ORANGEFS_KMOD_DEBUG_FILE)) {
+		debug_string_to_mask(buf, &orangefs_gossip_debug_mask, 0);
+		debug_mask_to_string(&orangefs_gossip_debug_mask, 0);
+		debug_string = kernel_debug_string;
+		gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+			     "New kernel debug string is %s\n",
+			     kernel_debug_string);
+	} else {
+		/* Can't reset client debug mask if client is not running. */
+		if (is_daemon_in_service()) {
+			pr_info("%s: Client not running :%d:\n",
+				__func__,
+				is_daemon_in_service());
+			goto out;
+		}
+
+		debug_string_to_mask(buf, &c_mask, 1);
+		debug_mask_to_string(&c_mask, 1);
+		debug_string = client_debug_string;
+
+		new_op = op_alloc(ORANGEFS_VFS_OP_PARAM);
+		if (!new_op) {
+			pr_info("%s: op_alloc failed!\n", __func__);
+			goto out;
+		}
+
+		new_op->upcall.req.param.op =
+			ORANGEFS_PARAM_REQUEST_OP_TWO_MASK_VALUES;
+		new_op->upcall.req.param.type = ORANGEFS_PARAM_REQUEST_SET;
+		memset(new_op->upcall.req.param.s_value,
+		       0,
+		       ORANGEFS_MAX_DEBUG_STRING_LEN);
+		sprintf(new_op->upcall.req.param.s_value,
+			"%llx %llx\n",
+			c_mask.mask1,
+			c_mask.mask2);
+
+		/* service_operation returns 0 on success... */
+		rc = service_operation(new_op,
+				       "orangefs_param",
+					ORANGEFS_OP_INTERRUPTIBLE);
+
+		if (rc)
+			gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+				     "%s: service_operation failed! rc:%d:\n",
+				     __func__,
+				     rc);
+
+		op_release(new_op);
+	}
+
+	mutex_lock(&orangefs_debug_lock);
+	s = file_inode(file)->i_private;
+	memset(s, 0, ORANGEFS_MAX_DEBUG_STRING_LEN);
+	sprintf(s, "%s\n", debug_string);
+	mutex_unlock(&orangefs_debug_lock);
+
+	*ppos += count;
+	if (silly)
+		rc = silly;
+	else
+		rc = count;
+
+out:
+	gossip_debug(GOSSIP_DEBUGFS_DEBUG,
+		     "orangefs_debug_write: rc: %d\n",
+		     rc);
+	kfree(buf);
+	return rc;
+}
+
+/*
+ * After obtaining a string representation of the client's debug
+ * keywords and their associated masks, this function is called to build an
+ * array of these values.
+ */
+static int orangefs_prepare_cdm_array(char *debug_array_string)
+{
+	int i;
+	int rc = -EINVAL;
+	char *cds_head = NULL;
+	char *cds_delimiter = NULL;
+	int keyword_len = 0;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: start\n", __func__);
+
+	/*
+	 * figure out how many elements the cdm_array needs.
+	 */
+	for (i = 0; i < strlen(debug_array_string); i++)
+		if (debug_array_string[i] == '\n')
+			cdm_element_count++;
+
+	if (!cdm_element_count) {
+		pr_info("No elements in client debug array string!\n");
+		goto out;
+	}
+
+	cdm_array = kcalloc(cdm_element_count, sizeof(*cdm_array), GFP_KERNEL);
+	if (!cdm_array) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	cds_head = debug_array_string;
+
+	for (i = 0; i < cdm_element_count; i++) {
+		cds_delimiter = strchr(cds_head, '\n');
+		*cds_delimiter = '\0';
+
+		keyword_len = strcspn(cds_head, " ");
+
+		cdm_array[i].keyword = kzalloc(keyword_len + 1, GFP_KERNEL);
+		if (!cdm_array[i].keyword) {
+			rc = -ENOMEM;
+			goto out;
+		}
+
+		sscanf(cds_head,
+		       "%s %llx %llx",
+		       cdm_array[i].keyword,
+		       (unsigned long long *)&(cdm_array[i].mask1),
+		       (unsigned long long *)&(cdm_array[i].mask2));
+
+		if (!strcmp(cdm_array[i].keyword, ORANGEFS_VERBOSE))
+			client_verbose_index = i;
+
+		if (!strcmp(cdm_array[i].keyword, ORANGEFS_ALL))
+			client_all_index = i;
+
+		cds_head = cds_delimiter + 1;
+	}
+
+	rc = cdm_element_count;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: rc:%d:\n", __func__, rc);
+
+out:
+
+	return rc;
+
+}
+
+/*
+ * /sys/kernel/debug/orangefs/debug-help can be catted to
+ * see all the available kernel and client debug keywords.
+ *
+ * When orangefs.ko initializes, we have no idea what keywords the
+ * client supports, nor their associated masks.
+ *
+ * We pass through this function once at module-load and stamp a
+ * boilerplate "we don't know" message for the client in the
+ * debug-help file. We pass through here again when the client
+ * starts and then we can fill out the debug-help file fully.
+ *
+ * The client might be restarted any number of times between
+ * module reloads, we only build the debug-help file the first time.
+ */
+int orangefs_prepare_debugfs_help_string(int at_boot)
+{
+	char *client_title = "Client Debug Keywords:\n";
+	char *kernel_title = "Kernel Debug Keywords:\n";
+	size_t string_size =  DEBUG_HELP_STRING_SIZE;
+	size_t result_size;
+	size_t i;
+	char *new;
+	int rc = -EINVAL;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: start\n", __func__);
+
+	if (at_boot)
+		client_title = HELP_STRING_UNINITIALIZED;
+
+	/* build a new debug_help_string. */
+	new = kzalloc(DEBUG_HELP_STRING_SIZE, GFP_KERNEL);
+	if (!new) {
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * strlcat(dst, src, size) will append at most
+	 * "size - strlen(dst) - 1" bytes of src onto dst,
+	 * null terminating the result, and return the total
+	 * length of the string it tried to create.
+	 *
+	 * We'll just plow through here building our new debug
+	 * help string and let strlcat take care of assuring that
+	 * dst doesn't overflow.
+	 */
+	strlcat(new, client_title, string_size);
+
+	if (!at_boot) {
+
+                /*
+		 * fill the client keyword/mask array and remember
+		 * how many elements there were.
+		 */
+		cdm_element_count =
+			orangefs_prepare_cdm_array(client_debug_array_string);
+		if (cdm_element_count <= 0) {
+			kfree(new);
+			goto out;
+		}
+
+		for (i = 0; i < cdm_element_count; i++) {
+			strlcat(new, "\t", string_size);
+			strlcat(new, cdm_array[i].keyword, string_size);
+			strlcat(new, "\n", string_size);
+		}
+	}
+
+	strlcat(new, "\n", string_size);
+	strlcat(new, kernel_title, string_size);
+
+	for (i = 0; i < num_kmod_keyword_mask_map; i++) {
+		strlcat(new, "\t", string_size);
+		strlcat(new, s_kmod_keyword_mask_map[i].keyword, string_size);
+		result_size = strlcat(new, "\n", string_size);
+	}
+
+	/* See if we tried to put too many bytes into "new"... */
+	if (result_size >= string_size) {
+		kfree(new);
+		goto out;
+	}
+
+	if (at_boot) {
+		debug_help_string = new;
+	} else {
+		mutex_lock(&orangefs_help_file_lock);
+		memset(debug_help_string, 0, DEBUG_HELP_STRING_SIZE);
+		strlcat(debug_help_string, new, string_size);
+		mutex_unlock(&orangefs_help_file_lock);
+		kfree(new);
+	}
+
+	rc = 0;
+
+out:	return rc;
+
+}
+
+/*
+ * kernel = type 0
+ * client = type 1
+ */
+static void debug_mask_to_string(void *mask, int type)
+{
+	int i;
+	int len = 0;
+	char *debug_string;
+	int element_count = 0;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: start\n", __func__);
+
+	if (type) {
+		debug_string = client_debug_string;
+		element_count = cdm_element_count;
+	} else {
+		debug_string = kernel_debug_string;
+		element_count = num_kmod_keyword_mask_map;
+	}
+
+	memset(debug_string, 0, ORANGEFS_MAX_DEBUG_STRING_LEN);
+
+	/*
+	 * Some keywords, like "all" or "verbose", are amalgams of
+	 * numerous other keywords. Make a special check for those
+	 * before grinding through the whole mask only to find out
+	 * later...
+	 */
+	if (check_amalgam_keyword(mask, type))
+		goto out;
+
+	/* Build the debug string. */
+	for (i = 0; i < element_count; i++)
+		if (type)
+			do_c_string(mask, i);
+		else
+			do_k_string(mask, i);
+
+	len = strlen(debug_string);
+
+	if ((len) && (type))
+		client_debug_string[len - 1] = '\0';
+	else if (len)
+		kernel_debug_string[len - 1] = '\0';
+	else if (type)
+		strcpy(client_debug_string, "none");
+	else
+		strcpy(kernel_debug_string, "none");
+
+out:
+gossip_debug(GOSSIP_UTILS_DEBUG, "%s: string:%s:\n", __func__, debug_string);
+
+	return;
+
+}
+
+static void do_k_string(void *k_mask, int index)
+{
+	__u64 *mask = (__u64 *) k_mask;
+
+	if (keyword_is_amalgam((char *) s_kmod_keyword_mask_map[index].keyword))
+		goto out;
+
+	if (*mask & s_kmod_keyword_mask_map[index].mask_val) {
+		if ((strlen(kernel_debug_string) +
+		     strlen(s_kmod_keyword_mask_map[index].keyword))
+			< ORANGEFS_MAX_DEBUG_STRING_LEN - 1) {
+				strcat(kernel_debug_string,
+				       s_kmod_keyword_mask_map[index].keyword);
+				strcat(kernel_debug_string, ",");
+			} else {
+				gossip_err("%s: overflow!\n", __func__);
+				strcpy(kernel_debug_string, ORANGEFS_ALL);
+				goto out;
+			}
+	}
+
+out:
+
+	return;
+}
+
+static void do_c_string(void *c_mask, int index)
+{
+	struct client_debug_mask *mask = (struct client_debug_mask *) c_mask;
+
+	if (keyword_is_amalgam(cdm_array[index].keyword))
+		goto out;
+
+	if ((mask->mask1 & cdm_array[index].mask1) ||
+	    (mask->mask2 & cdm_array[index].mask2)) {
+		if ((strlen(client_debug_string) +
+		     strlen(cdm_array[index].keyword) + 1)
+			< ORANGEFS_MAX_DEBUG_STRING_LEN - 2) {
+				strcat(client_debug_string,
+				       cdm_array[index].keyword);
+				strcat(client_debug_string, ",");
+			} else {
+				gossip_err("%s: overflow!\n", __func__);
+				strcpy(client_debug_string, ORANGEFS_ALL);
+				goto out;
+			}
+	}
+out:
+	return;
+}
+
+static int keyword_is_amalgam(char *keyword)
+{
+	int rc = 0;
+
+	if ((!strcmp(keyword, ORANGEFS_ALL)) || (!strcmp(keyword, ORANGEFS_VERBOSE)))
+		rc = 1;
+
+	return rc;
+}
+
+/*
+ * kernel = type 0
+ * client = type 1
+ *
+ * return 1 if we found an amalgam.
+ */
+static int check_amalgam_keyword(void *mask, int type)
+{
+	__u64 *k_mask;
+	struct client_debug_mask *c_mask;
+	int k_all_index = num_kmod_keyword_mask_map - 1;
+	int rc = 0;
+
+	if (type) {
+		c_mask = (struct client_debug_mask *) mask;
+
+		if ((c_mask->mask1 == cdm_array[client_all_index].mask1) &&
+		    (c_mask->mask2 == cdm_array[client_all_index].mask2)) {
+			strcpy(client_debug_string, ORANGEFS_ALL);
+			rc = 1;
+			goto out;
+		}
+
+		if ((c_mask->mask1 == cdm_array[client_verbose_index].mask1) &&
+		    (c_mask->mask2 == cdm_array[client_verbose_index].mask2)) {
+			strcpy(client_debug_string, ORANGEFS_VERBOSE);
+			rc = 1;
+			goto out;
+		}
+
+	} else {
+		k_mask = (__u64 *) mask;
+
+		if (*k_mask >= s_kmod_keyword_mask_map[k_all_index].mask_val) {
+			strcpy(kernel_debug_string, ORANGEFS_ALL);
+			rc = 1;
+			goto out;
+		}
+	}
+
+out:
+
+	return rc;
+}
+
+/*
+ * kernel = type 0
+ * client = type 1
+ */
+static void debug_string_to_mask(char *debug_string, void *mask, int type)
+{
+	char *unchecked_keyword;
+	int i;
+	char *strsep_fodder = kstrdup(debug_string, GFP_KERNEL);
+	char *original_pointer;
+	int element_count = 0;
+	struct client_debug_mask *c_mask = NULL;
+	__u64 *k_mask = NULL;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: start\n", __func__);
+
+	if (type) {
+		c_mask = (struct client_debug_mask *)mask;
+		element_count = cdm_element_count;
+	} else {
+		k_mask = (__u64 *)mask;
+		*k_mask = 0;
+		element_count = num_kmod_keyword_mask_map;
+	}
+
+	original_pointer = strsep_fodder;
+	while ((unchecked_keyword = strsep(&strsep_fodder, ",")))
+		if (strlen(unchecked_keyword)) {
+			for (i = 0; i < element_count; i++)
+				if (type)
+					do_c_mask(i,
+						  unchecked_keyword,
+						  &c_mask);
+				else
+					do_k_mask(i,
+						  unchecked_keyword,
+						  &k_mask);
+		}
+
+	kfree(original_pointer);
+}
+
+static void do_c_mask(int i, char *unchecked_keyword,
+    struct client_debug_mask **sane_mask)
+{
+
+	if (!strcmp(cdm_array[i].keyword, unchecked_keyword)) {
+		(**sane_mask).mask1 = (**sane_mask).mask1 | cdm_array[i].mask1;
+		(**sane_mask).mask2 = (**sane_mask).mask2 | cdm_array[i].mask2;
+	}
+}
+
+static void do_k_mask(int i, char *unchecked_keyword, __u64 **sane_mask)
+{
+
+	if (!strcmp(s_kmod_keyword_mask_map[i].keyword, unchecked_keyword))
+		**sane_mask = (**sane_mask) |
+				s_kmod_keyword_mask_map[i].mask_val;
+}
+
+int orangefs_debugfs_new_client_mask(void __user *arg)
+{
+	struct dev_mask2_info_s mask2_info = {0};
+	int ret;
+
+	ret = copy_from_user(&mask2_info,
+			     (void __user *)arg,
+			     sizeof(struct dev_mask2_info_s));
+
+	if (ret != 0)
+		return -EIO;
+
+	client_debug_mask.mask1 = mask2_info.mask1_value;
+	client_debug_mask.mask2 = mask2_info.mask2_value;
+
+	pr_info("%s: client debug mask has been been received "
+		":%llx: :%llx:\n",
+		__func__,
+		(unsigned long long)client_debug_mask.mask1,
+		(unsigned long long)client_debug_mask.mask2);
+
+	return ret;
+}
+
+int orangefs_debugfs_new_client_string(void __user *arg)
+{
+	int ret;
+
+	ret = copy_from_user(&client_debug_array_string,
+			     (void __user *)arg,
+			     ORANGEFS_MAX_DEBUG_STRING_LEN);
+
+	if (ret != 0) {
+		pr_info("%s: CLIENT_STRING: copy_from_user failed\n",
+			__func__);
+		return -EFAULT;
+	}
+
+	/*
+	 * The real client-core makes an effort to ensure
+	 * that actual strings that aren't too long to fit in
+	 * this buffer is what we get here. We're going to use
+	 * string functions on the stuff we got, so we'll make
+	 * this extra effort to try and keep from
+	 * flowing out of this buffer when we use the string
+	 * functions, even if somehow the stuff we end up
+	 * with here is garbage.
+	 */
+	client_debug_array_string[ORANGEFS_MAX_DEBUG_STRING_LEN - 1] =
+		'\0';
+
+	pr_info("%s: client debug array string has been received.\n",
+		__func__);
+
+	if (!help_string_initialized) {
+
+		/* Build a proper debug help string. */
+		ret = orangefs_prepare_debugfs_help_string(0);
+		if (ret) {
+			gossip_err("%s: no debug help string \n",
+				   __func__);
+			return ret;
+		}
+
+	}
+
+	debug_mask_to_string(&client_debug_mask, 1);
+
+	debugfs_remove(client_debug_dentry);
+
+	orangefs_client_debug_init();
+
+	help_string_initialized++;
+
+	return 0;
+}
+
+int orangefs_debugfs_new_debug(void __user *arg)
+{
+	struct dev_mask_info_s mask_info = {0};
+	int ret;
+
+	ret = copy_from_user(&mask_info,
+			     (void __user *)arg,
+			     sizeof(mask_info));
+
+	if (ret != 0)
+		return -EIO;
+
+	if (mask_info.mask_type == KERNEL_MASK) {
+		if ((mask_info.mask_value == 0)
+		    && (kernel_mask_set_mod_init)) {
+			/*
+			 * the kernel debug mask was set when the
+			 * kernel module was loaded; don't override
+			 * it if the client-core was started without
+			 * a value for ORANGEFS_KMODMASK.
+			 */
+			return 0;
+		}
+		debug_mask_to_string(&mask_info.mask_value,
+				     mask_info.mask_type);
+		orangefs_gossip_debug_mask = mask_info.mask_value;
+		pr_info("%s: kernel debug mask has been modified to "
+			":%s: :%llx:\n",
+			__func__,
+			kernel_debug_string,
+			(unsigned long long)orangefs_gossip_debug_mask);
+	} else if (mask_info.mask_type == CLIENT_MASK) {
+		debug_mask_to_string(&mask_info.mask_value,
+				     mask_info.mask_type);
+		pr_info("%s: client debug mask has been modified to"
+			":%s: :%llx:\n",
+			__func__,
+			client_debug_string,
+			llu(mask_info.mask_value));
+	} else {
+		gossip_err("Invalid mask type....\n");
+		return -EINVAL;
+	}
+
+	return ret;
+}
diff --git a/fs/orangefs/orangefs-debugfs.h b/fs/orangefs/orangefs-debugfs.h
new file mode 100644
index 000000000..502f6dedc
--- /dev/null
+++ b/fs/orangefs/orangefs-debugfs.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+void orangefs_debugfs_init(int);
+void orangefs_debugfs_cleanup(void);
+int orangefs_prepare_debugfs_help_string(int);
+int orangefs_debugfs_new_client_mask(void __user *);
+int orangefs_debugfs_new_client_string(void __user *);
+int orangefs_debugfs_new_debug(void __user *);
diff --git a/fs/orangefs/orangefs-dev-proto.h b/fs/orangefs/orangefs-dev-proto.h
new file mode 100644
index 000000000..dc6609824
--- /dev/null
+++ b/fs/orangefs/orangefs-dev-proto.h
@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#ifndef _ORANGEFS_DEV_PROTO_H
+#define _ORANGEFS_DEV_PROTO_H
+
+/*
+ * types and constants shared between user space and kernel space for
+ * device interaction using a common protocol
+ */
+
+/*
+ * valid orangefs kernel operation types
+ */
+#define ORANGEFS_VFS_OP_INVALID           0xFF000000
+#define ORANGEFS_VFS_OP_FILE_IO        0xFF000001
+#define ORANGEFS_VFS_OP_LOOKUP         0xFF000002
+#define ORANGEFS_VFS_OP_CREATE         0xFF000003
+#define ORANGEFS_VFS_OP_GETATTR        0xFF000004
+#define ORANGEFS_VFS_OP_REMOVE         0xFF000005
+#define ORANGEFS_VFS_OP_MKDIR          0xFF000006
+#define ORANGEFS_VFS_OP_READDIR        0xFF000007
+#define ORANGEFS_VFS_OP_SETATTR        0xFF000008
+#define ORANGEFS_VFS_OP_SYMLINK        0xFF000009
+#define ORANGEFS_VFS_OP_RENAME         0xFF00000A
+#define ORANGEFS_VFS_OP_STATFS         0xFF00000B
+#define ORANGEFS_VFS_OP_TRUNCATE       0xFF00000C
+#define ORANGEFS_VFS_OP_RA_FLUSH       0xFF00000D
+#define ORANGEFS_VFS_OP_FS_MOUNT       0xFF00000E
+#define ORANGEFS_VFS_OP_FS_UMOUNT      0xFF00000F
+#define ORANGEFS_VFS_OP_GETXATTR       0xFF000010
+#define ORANGEFS_VFS_OP_SETXATTR          0xFF000011
+#define ORANGEFS_VFS_OP_LISTXATTR         0xFF000012
+#define ORANGEFS_VFS_OP_REMOVEXATTR       0xFF000013
+#define ORANGEFS_VFS_OP_PARAM          0xFF000014
+#define ORANGEFS_VFS_OP_PERF_COUNT     0xFF000015
+#define ORANGEFS_VFS_OP_CANCEL            0xFF00EE00
+#define ORANGEFS_VFS_OP_FSYNC          0xFF00EE01
+#define ORANGEFS_VFS_OP_FSKEY             0xFF00EE02
+#define ORANGEFS_VFS_OP_READDIRPLUS       0xFF00EE03
+#define ORANGEFS_VFS_OP_FEATURES	0xFF00EE05 /* 2.9.6 */
+
+/* features is a 64-bit unsigned bitmask */
+#define ORANGEFS_FEATURE_READAHEAD 1
+
+/*
+ * Misc constants. Please retain them as multiples of 8!
+ * Otherwise 32-64 bit interactions will be messed up :)
+ */
+#define ORANGEFS_MAX_DEBUG_STRING_LEN	0x00000800
+
+#define ORANGEFS_MAX_DIRENT_COUNT_READDIR 512
+
+#include "upcall.h"
+#include "downcall.h"
+
+#endif
diff --git a/fs/orangefs/orangefs-kernel.h b/fs/orangefs/orangefs-kernel.h
new file mode 100644
index 000000000..b5940ec18
--- /dev/null
+++ b/fs/orangefs/orangefs-kernel.h
@@ -0,0 +1,492 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  The ORANGEFS Linux kernel support allows ORANGEFS volumes to be mounted and
+ *  accessed through the Linux VFS (i.e. using standard I/O system calls).
+ *  This support is only needed on clients that wish to mount the file system.
+ *
+ */
+
+/*
+ *  Declarations and macros for the ORANGEFS Linux kernel support.
+ */
+
+#ifndef __ORANGEFSKERNEL_H
+#define __ORANGEFSKERNEL_H
+
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/statfs.h>
+#include <linux/backing-dev.h>
+#include <linux/device.h>
+#include <linux/mpage.h>
+#include <linux/namei.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/vmalloc.h>
+
+#include <linux/aio.h>
+#include <linux/posix_acl.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
+#include <linux/uaccess.h>
+#include <linux/atomic.h>
+#include <linux/uio.h>
+#include <linux/sched/signal.h>
+#include <linux/mm.h>
+#include <linux/wait.h>
+#include <linux/dcache.h>
+#include <linux/pagemap.h>
+#include <linux/poll.h>
+#include <linux/rwsem.h>
+#include <linux/xattr.h>
+#include <linux/exportfs.h>
+#include <linux/hashtable.h>
+
+#include <asm/unaligned.h>
+
+#include "orangefs-dev-proto.h"
+
+#define ORANGEFS_DEFAULT_OP_TIMEOUT_SECS       20
+
+#define ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS   30
+
+#define ORANGEFS_DEFAULT_SLOT_TIMEOUT_SECS     900	/* 15 minutes */
+
+#define ORANGEFS_REQDEVICE_NAME          "pvfs2-req"
+
+#define ORANGEFS_DEVREQ_MAGIC             0x20030529
+#define ORANGEFS_PURGE_RETRY_COUNT     0x00000005
+
+#define MAX_DEV_REQ_UPSIZE (2 * sizeof(__s32) +   \
+sizeof(__u64) + sizeof(struct orangefs_upcall_s))
+#define MAX_DEV_REQ_DOWNSIZE (2 * sizeof(__s32) + \
+sizeof(__u64) + sizeof(struct orangefs_downcall_s))
+
+/*
+ * valid orangefs kernel operation states
+ *
+ * unknown  - op was just initialized
+ * waiting  - op is on request_list (upward bound)
+ * inprogr  - op is in progress (waiting for downcall)
+ * serviced - op has matching downcall; ok
+ * purged   - op has to start a timer since client-core
+ *            exited uncleanly before servicing op
+ * given up - submitter has given up waiting for it
+ */
+enum orangefs_vfs_op_states {
+	OP_VFS_STATE_UNKNOWN = 0,
+	OP_VFS_STATE_WAITING = 1,
+	OP_VFS_STATE_INPROGR = 2,
+	OP_VFS_STATE_SERVICED = 4,
+	OP_VFS_STATE_PURGED = 8,
+	OP_VFS_STATE_GIVEN_UP = 16,
+};
+
+/*
+ * orangefs kernel memory related flags
+ */
+
+#if (defined CONFIG_DEBUG_SLAB)
+#define ORANGEFS_CACHE_CREATE_FLAGS SLAB_RED_ZONE
+#else
+#define ORANGEFS_CACHE_CREATE_FLAGS 0
+#endif
+
+extern int orangefs_init_acl(struct inode *inode, struct inode *dir);
+extern const struct xattr_handler *orangefs_xattr_handlers[];
+
+extern struct posix_acl *orangefs_get_acl(struct inode *inode, int type, bool rcu);
+extern int orangefs_set_acl(struct user_namespace *mnt_userns,
+			    struct inode *inode, struct posix_acl *acl,
+			    int type);
+
+/*
+ * orangefs data structures
+ */
+struct orangefs_kernel_op_s {
+	enum orangefs_vfs_op_states op_state;
+	__u64 tag;
+
+	/*
+	 * Set uses_shared_memory to non zero if this operation uses
+	 * shared memory. If true, then a retry on the op must also
+	 * get a new shared memory buffer and re-populate it.
+	 * Cancels don't care - it only matters for service_operation()
+	 * retry logics and cancels don't go through it anymore. It
+	 * safely stays non-zero when we use it as slot_to_free.
+	 */
+	union {
+		int uses_shared_memory;
+		int slot_to_free;
+	};
+
+	struct orangefs_upcall_s upcall;
+	struct orangefs_downcall_s downcall;
+
+	struct completion waitq;
+	spinlock_t lock;
+
+	int attempts;
+
+	struct list_head list;
+};
+
+#define set_op_state_waiting(op)     ((op)->op_state = OP_VFS_STATE_WAITING)
+#define set_op_state_inprogress(op)  ((op)->op_state = OP_VFS_STATE_INPROGR)
+#define set_op_state_given_up(op)  ((op)->op_state = OP_VFS_STATE_GIVEN_UP)
+static inline void set_op_state_serviced(struct orangefs_kernel_op_s *op)
+{
+	op->op_state = OP_VFS_STATE_SERVICED;
+	complete(&op->waitq);
+}
+
+#define op_state_waiting(op)     ((op)->op_state & OP_VFS_STATE_WAITING)
+#define op_state_in_progress(op) ((op)->op_state & OP_VFS_STATE_INPROGR)
+#define op_state_serviced(op)    ((op)->op_state & OP_VFS_STATE_SERVICED)
+#define op_state_purged(op)      ((op)->op_state & OP_VFS_STATE_PURGED)
+#define op_state_given_up(op)    ((op)->op_state & OP_VFS_STATE_GIVEN_UP)
+#define op_is_cancel(op)         ((op)->upcall.type == ORANGEFS_VFS_OP_CANCEL)
+
+void op_release(struct orangefs_kernel_op_s *op);
+
+extern void orangefs_bufmap_put(int);
+static inline void put_cancel(struct orangefs_kernel_op_s *op)
+{
+	orangefs_bufmap_put(op->slot_to_free);
+	op_release(op);
+}
+
+static inline void set_op_state_purged(struct orangefs_kernel_op_s *op)
+{
+	spin_lock(&op->lock);
+	if (unlikely(op_is_cancel(op))) {
+		list_del_init(&op->list);
+		spin_unlock(&op->lock);
+		put_cancel(op);
+	} else {
+		op->op_state |= OP_VFS_STATE_PURGED;
+		complete(&op->waitq);
+		spin_unlock(&op->lock);
+	}
+}
+
+/* per inode private orangefs info */
+struct orangefs_inode_s {
+	struct orangefs_object_kref refn;
+	char link_target[ORANGEFS_NAME_MAX];
+	/*
+	 * Reading/Writing Extended attributes need to acquire the appropriate
+	 * reader/writer semaphore on the orangefs_inode_s structure.
+	 */
+	struct rw_semaphore xattr_sem;
+
+	struct inode vfs_inode;
+	sector_t last_failed_block_index_read;
+
+	unsigned long getattr_time;
+	unsigned long mapping_time;
+	int attr_valid;
+	kuid_t attr_uid;
+	kgid_t attr_gid;
+	unsigned long bitlock;
+
+	DECLARE_HASHTABLE(xattr_cache, 4);
+};
+
+/* per superblock private orangefs info */
+struct orangefs_sb_info_s {
+	struct orangefs_khandle root_khandle;
+	__s32 fs_id;
+	int id;
+	int flags;
+#define ORANGEFS_OPT_INTR	0x01
+#define ORANGEFS_OPT_LOCAL_LOCK	0x02
+	char devname[ORANGEFS_MAX_SERVER_ADDR_LEN];
+	struct super_block *sb;
+	int mount_pending;
+	int no_list;
+	struct list_head list;
+};
+
+struct orangefs_stats {
+	unsigned long cache_hits;
+	unsigned long cache_misses;
+	unsigned long reads;
+	unsigned long writes;
+};
+
+struct orangefs_cached_xattr {
+	struct hlist_node node;
+	char key[ORANGEFS_MAX_XATTR_NAMELEN];
+	char val[ORANGEFS_MAX_XATTR_VALUELEN];
+	ssize_t length;
+	unsigned long timeout;
+};
+
+struct orangefs_write_range {
+	loff_t pos;
+	size_t len;
+	kuid_t uid;
+	kgid_t gid;
+};
+
+extern struct orangefs_stats orangefs_stats;
+
+/*
+ * NOTE: See Documentation/filesystems/porting.rst for information
+ * on implementing FOO_I and properly accessing fs private data
+ */
+static inline struct orangefs_inode_s *ORANGEFS_I(struct inode *inode)
+{
+	return container_of(inode, struct orangefs_inode_s, vfs_inode);
+}
+
+static inline struct orangefs_sb_info_s *ORANGEFS_SB(struct super_block *sb)
+{
+	return (struct orangefs_sb_info_s *) sb->s_fs_info;
+}
+
+/* ino_t descends from "unsigned long", 8 bytes, 64 bits. */
+static inline ino_t orangefs_khandle_to_ino(struct orangefs_khandle *khandle)
+{
+	union {
+		unsigned char u[8];
+		__u64 ino;
+	} ihandle;
+
+	ihandle.u[0] = khandle->u[0] ^ khandle->u[4];
+	ihandle.u[1] = khandle->u[1] ^ khandle->u[5];
+	ihandle.u[2] = khandle->u[2] ^ khandle->u[6];
+	ihandle.u[3] = khandle->u[3] ^ khandle->u[7];
+	ihandle.u[4] = khandle->u[12] ^ khandle->u[8];
+	ihandle.u[5] = khandle->u[13] ^ khandle->u[9];
+	ihandle.u[6] = khandle->u[14] ^ khandle->u[10];
+	ihandle.u[7] = khandle->u[15] ^ khandle->u[11];
+
+	return ihandle.ino;
+}
+
+static inline struct orangefs_khandle *get_khandle_from_ino(struct inode *inode)
+{
+	return &(ORANGEFS_I(inode)->refn.khandle);
+}
+
+static inline int is_root_handle(struct inode *inode)
+{
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s: root handle: %pU, this handle: %pU:\n",
+		     __func__,
+		     &ORANGEFS_SB(inode->i_sb)->root_khandle,
+		     get_khandle_from_ino(inode));
+
+	if (ORANGEFS_khandle_cmp(&(ORANGEFS_SB(inode->i_sb)->root_khandle),
+			     get_khandle_from_ino(inode)))
+		return 0;
+	else
+		return 1;
+}
+
+static inline int match_handle(struct orangefs_khandle resp_handle,
+			       struct inode *inode)
+{
+	gossip_debug(GOSSIP_DCACHE_DEBUG,
+		     "%s: one handle: %pU, another handle:%pU:\n",
+		     __func__,
+		     &resp_handle,
+		     get_khandle_from_ino(inode));
+
+	if (ORANGEFS_khandle_cmp(&resp_handle, get_khandle_from_ino(inode)))
+		return 0;
+	else
+		return 1;
+}
+
+/*
+ * defined in orangefs-cache.c
+ */
+int op_cache_initialize(void);
+int op_cache_finalize(void);
+struct orangefs_kernel_op_s *op_alloc(__s32 type);
+void orangefs_new_tag(struct orangefs_kernel_op_s *op);
+char *get_opname_string(struct orangefs_kernel_op_s *new_op);
+
+int orangefs_inode_cache_initialize(void);
+int orangefs_inode_cache_finalize(void);
+
+/*
+ * defined in orangefs-mod.c
+ */
+void purge_inprogress_ops(void);
+
+/*
+ * defined in waitqueue.c
+ */
+void purge_waiting_ops(void);
+
+/*
+ * defined in super.c
+ */
+extern uint64_t orangefs_features;
+
+struct dentry *orangefs_mount(struct file_system_type *fst,
+			   int flags,
+			   const char *devname,
+			   void *data);
+
+void orangefs_kill_sb(struct super_block *sb);
+int orangefs_remount(struct orangefs_sb_info_s *);
+
+int fsid_key_table_initialize(void);
+void fsid_key_table_finalize(void);
+
+/*
+ * defined in inode.c
+ */
+vm_fault_t orangefs_page_mkwrite(struct vm_fault *);
+struct inode *orangefs_new_inode(struct super_block *sb,
+			      struct inode *dir,
+			      int mode,
+			      dev_t dev,
+			      struct orangefs_object_kref *ref);
+
+int __orangefs_setattr(struct inode *, struct iattr *);
+int orangefs_setattr(struct user_namespace *, struct dentry *, struct iattr *);
+
+int orangefs_getattr(struct user_namespace *mnt_userns, const struct path *path,
+		     struct kstat *stat, u32 request_mask, unsigned int flags);
+
+int orangefs_permission(struct user_namespace *mnt_userns,
+			struct inode *inode, int mask);
+
+int orangefs_update_time(struct inode *, struct timespec64 *, int);
+
+/*
+ * defined in xattr.c
+ */
+ssize_t orangefs_listxattr(struct dentry *dentry, char *buffer, size_t size);
+
+/*
+ * defined in namei.c
+ */
+struct inode *orangefs_iget(struct super_block *sb,
+			 struct orangefs_object_kref *ref);
+
+/*
+ * defined in devorangefs-req.c
+ */
+extern uint32_t orangefs_userspace_version;
+
+int orangefs_dev_init(void);
+void orangefs_dev_cleanup(void);
+int is_daemon_in_service(void);
+bool __is_daemon_in_service(void);
+
+/*
+ * defined in file.c
+ */
+int orangefs_revalidate_mapping(struct inode *);
+ssize_t wait_for_direct_io(enum ORANGEFS_io_type, struct inode *, loff_t *,
+    struct iov_iter *, size_t, loff_t, struct orangefs_write_range *, int *,
+    struct file *);
+ssize_t do_readv_writev(enum ORANGEFS_io_type, struct file *, loff_t *,
+    struct iov_iter *);
+
+/*
+ * defined in orangefs-utils.c
+ */
+__s32 fsid_of_op(struct orangefs_kernel_op_s *op);
+
+ssize_t orangefs_inode_getxattr(struct inode *inode,
+			     const char *name,
+			     void *buffer,
+			     size_t size);
+
+int orangefs_inode_setxattr(struct inode *inode,
+			 const char *name,
+			 const void *value,
+			 size_t size,
+			 int flags);
+
+#define ORANGEFS_GETATTR_NEW 1
+#define ORANGEFS_GETATTR_SIZE 2
+
+int orangefs_inode_getattr(struct inode *, int);
+
+int orangefs_inode_check_changed(struct inode *inode);
+
+int orangefs_inode_setattr(struct inode *inode);
+
+bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op);
+
+int orangefs_normalize_to_errno(__s32 error_code);
+
+extern struct mutex orangefs_request_mutex;
+extern int op_timeout_secs;
+extern int slot_timeout_secs;
+extern int orangefs_cache_timeout_msecs;
+extern int orangefs_dcache_timeout_msecs;
+extern int orangefs_getattr_timeout_msecs;
+extern struct list_head orangefs_superblocks;
+extern spinlock_t orangefs_superblocks_lock;
+extern struct list_head orangefs_request_list;
+extern spinlock_t orangefs_request_list_lock;
+extern wait_queue_head_t orangefs_request_list_waitq;
+extern struct list_head *orangefs_htable_ops_in_progress;
+extern spinlock_t orangefs_htable_ops_in_progress_lock;
+extern int hash_table_size;
+
+extern const struct file_operations orangefs_file_operations;
+extern const struct inode_operations orangefs_symlink_inode_operations;
+extern const struct inode_operations orangefs_dir_inode_operations;
+extern const struct file_operations orangefs_dir_operations;
+extern const struct dentry_operations orangefs_dentry_operations;
+
+/*
+ * misc convenience macros
+ */
+
+#define ORANGEFS_OP_INTERRUPTIBLE 1   /* service_operation() is interruptible */
+#define ORANGEFS_OP_PRIORITY      2   /* service_operation() is high priority */
+#define ORANGEFS_OP_CANCELLATION  4   /* this is a cancellation */
+#define ORANGEFS_OP_NO_MUTEX      8   /* don't acquire request_mutex */
+#define ORANGEFS_OP_ASYNC         16  /* Queue it, but don't wait */
+#define ORANGEFS_OP_WRITEBACK     32
+
+int service_operation(struct orangefs_kernel_op_s *op,
+		      const char *op_name,
+		      int flags);
+
+#define get_interruptible_flag(inode) \
+	((ORANGEFS_SB(inode->i_sb)->flags & ORANGEFS_OPT_INTR) ? \
+		ORANGEFS_OP_INTERRUPTIBLE : 0)
+
+#define fill_default_sys_attrs(sys_attr, type, mode)			\
+do {									\
+	sys_attr.owner = from_kuid(&init_user_ns, current_fsuid()); \
+	sys_attr.group = from_kgid(&init_user_ns, current_fsgid()); \
+	sys_attr.perms = ORANGEFS_util_translate_mode(mode);		\
+	sys_attr.mtime = 0;						\
+	sys_attr.atime = 0;						\
+	sys_attr.ctime = 0;						\
+	sys_attr.mask = ORANGEFS_ATTR_SYS_ALL_SETABLE;			\
+} while (0)
+
+static inline void orangefs_set_timeout(struct dentry *dentry)
+{
+	unsigned long time = jiffies + orangefs_dcache_timeout_msecs*HZ/1000;
+
+	dentry->d_fsdata = (void *) time;
+}
+
+#endif /* __ORANGEFSKERNEL_H */
diff --git a/fs/orangefs/orangefs-mod.c b/fs/orangefs/orangefs-mod.c
new file mode 100644
index 000000000..5ab741c60
--- /dev/null
+++ b/fs/orangefs/orangefs-mod.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * Changes by Acxiom Corporation to add proc file handler for pvfs2 client
+ * parameters, Copyright Acxiom Corporation, 2005.
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-debugfs.h"
+#include "orangefs-sysfs.h"
+
+/* ORANGEFS_VERSION is a ./configure define */
+#ifndef ORANGEFS_VERSION
+#define ORANGEFS_VERSION "upstream"
+#endif
+
+/*
+ * global variables declared here
+ */
+
+struct orangefs_stats orangefs_stats;
+
+/* the size of the hash tables for ops in progress */
+int hash_table_size = 509;
+
+static ulong module_parm_debug_mask;
+__u64 orangefs_gossip_debug_mask;
+int op_timeout_secs = ORANGEFS_DEFAULT_OP_TIMEOUT_SECS;
+int slot_timeout_secs = ORANGEFS_DEFAULT_SLOT_TIMEOUT_SECS;
+int orangefs_cache_timeout_msecs = 500;
+int orangefs_dcache_timeout_msecs = 50;
+int orangefs_getattr_timeout_msecs = 50;
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("ORANGEFS Development Team");
+MODULE_DESCRIPTION("The Linux Kernel VFS interface to ORANGEFS");
+MODULE_PARM_DESC(module_parm_debug_mask, "debugging level (see orangefs-debug.h for values)");
+MODULE_PARM_DESC(op_timeout_secs, "Operation timeout in seconds");
+MODULE_PARM_DESC(slot_timeout_secs, "Slot timeout in seconds");
+MODULE_PARM_DESC(hash_table_size,
+		 "size of hash table for operations in progress");
+
+static struct file_system_type orangefs_fs_type = {
+	.name = "pvfs2",
+	.mount = orangefs_mount,
+	.kill_sb = orangefs_kill_sb,
+	.owner = THIS_MODULE,
+};
+
+module_param(hash_table_size, int, 0);
+module_param(module_parm_debug_mask, ulong, 0644);
+module_param(op_timeout_secs, int, 0);
+module_param(slot_timeout_secs, int, 0);
+
+/*
+ * Blocks non-priority requests from being queued for servicing.  This
+ * could be used for protecting the request list data structure, but
+ * for now it's only being used to stall the op addition to the request
+ * list
+ */
+DEFINE_MUTEX(orangefs_request_mutex);
+
+/* hash table for storing operations waiting for matching downcall */
+struct list_head *orangefs_htable_ops_in_progress;
+DEFINE_SPINLOCK(orangefs_htable_ops_in_progress_lock);
+
+/* list for queueing upcall operations */
+LIST_HEAD(orangefs_request_list);
+
+/* used to protect the above orangefs_request_list */
+DEFINE_SPINLOCK(orangefs_request_list_lock);
+
+/* used for incoming request notification */
+DECLARE_WAIT_QUEUE_HEAD(orangefs_request_list_waitq);
+
+static int __init orangefs_init(void)
+{
+	int ret;
+	__u32 i = 0;
+
+	if (op_timeout_secs < 0)
+		op_timeout_secs = 0;
+
+	if (slot_timeout_secs < 0)
+		slot_timeout_secs = 0;
+
+	/* initialize global book keeping data structures */
+	ret = op_cache_initialize();
+	if (ret < 0)
+		goto out;
+
+	ret = orangefs_inode_cache_initialize();
+	if (ret < 0)
+		goto cleanup_op;
+
+	orangefs_htable_ops_in_progress =
+	    kcalloc(hash_table_size, sizeof(struct list_head), GFP_KERNEL);
+	if (!orangefs_htable_ops_in_progress) {
+		ret = -ENOMEM;
+		goto cleanup_inode;
+	}
+
+	/* initialize a doubly linked at each hash table index */
+	for (i = 0; i < hash_table_size; i++)
+		INIT_LIST_HEAD(&orangefs_htable_ops_in_progress[i]);
+
+	ret = fsid_key_table_initialize();
+	if (ret < 0)
+		goto cleanup_progress_table;
+
+	/*
+	 * Build the contents of /sys/kernel/debug/orangefs/debug-help
+	 * from the keywords in the kernel keyword/mask array.
+	 *
+	 * The keywords in the client keyword/mask array are
+	 * unknown at boot time.
+	 *
+	 * orangefs_prepare_debugfs_help_string will be used again
+	 * later to rebuild the debug-help-string after the client starts
+	 * and passes along the needed info. The argument signifies
+	 * which time orangefs_prepare_debugfs_help_string is being
+	 * called.
+	 */
+	ret = orangefs_prepare_debugfs_help_string(1);
+	if (ret)
+		goto cleanup_key_table;
+
+	orangefs_debugfs_init(module_parm_debug_mask);
+
+	ret = orangefs_sysfs_init();
+	if (ret)
+		goto sysfs_init_failed;
+
+	/* Initialize the orangefsdev subsystem. */
+	ret = orangefs_dev_init();
+	if (ret < 0) {
+		gossip_err("%s: could not initialize device subsystem %d!\n",
+			   __func__,
+			   ret);
+		goto cleanup_sysfs;
+	}
+
+	ret = register_filesystem(&orangefs_fs_type);
+	if (ret == 0) {
+		pr_info("%s: module version %s loaded\n",
+			__func__,
+			ORANGEFS_VERSION);
+		goto out;
+	}
+
+	orangefs_dev_cleanup();
+
+cleanup_sysfs:
+	orangefs_sysfs_exit();
+
+sysfs_init_failed:
+	orangefs_debugfs_cleanup();
+
+cleanup_key_table:
+	fsid_key_table_finalize();
+
+cleanup_progress_table:
+	kfree(orangefs_htable_ops_in_progress);
+
+cleanup_inode:
+	orangefs_inode_cache_finalize();
+
+cleanup_op:
+	op_cache_finalize();
+
+out:
+	return ret;
+}
+
+static void __exit orangefs_exit(void)
+{
+	int i = 0;
+	gossip_debug(GOSSIP_INIT_DEBUG, "orangefs: orangefs_exit called\n");
+
+	unregister_filesystem(&orangefs_fs_type);
+	orangefs_debugfs_cleanup();
+	orangefs_sysfs_exit();
+	fsid_key_table_finalize();
+	orangefs_dev_cleanup();
+	BUG_ON(!list_empty(&orangefs_request_list));
+	for (i = 0; i < hash_table_size; i++)
+		BUG_ON(!list_empty(&orangefs_htable_ops_in_progress[i]));
+
+	orangefs_inode_cache_finalize();
+	op_cache_finalize();
+
+	kfree(orangefs_htable_ops_in_progress);
+
+	pr_info("orangefs: module version %s unloaded\n", ORANGEFS_VERSION);
+}
+
+/*
+ * What we do in this function is to walk the list of operations
+ * that are in progress in the hash table and mark them as purged as well.
+ */
+void purge_inprogress_ops(void)
+{
+	int i;
+
+	for (i = 0; i < hash_table_size; i++) {
+		struct orangefs_kernel_op_s *op;
+		struct orangefs_kernel_op_s *next;
+
+		spin_lock(&orangefs_htable_ops_in_progress_lock);
+		list_for_each_entry_safe(op,
+					 next,
+					 &orangefs_htable_ops_in_progress[i],
+					 list) {
+			set_op_state_purged(op);
+			gossip_debug(GOSSIP_DEV_DEBUG,
+				     "%s: op:%s: op_state:%d: process:%s:\n",
+				     __func__,
+				     get_opname_string(op),
+				     op->op_state,
+				     current->comm);
+		}
+		spin_unlock(&orangefs_htable_ops_in_progress_lock);
+	}
+}
+
+module_init(orangefs_init);
+module_exit(orangefs_exit);
diff --git a/fs/orangefs/orangefs-sysfs.c b/fs/orangefs/orangefs-sysfs.c
new file mode 100644
index 000000000..be4ba03a0
--- /dev/null
+++ b/fs/orangefs/orangefs-sysfs.c
@@ -0,0 +1,1326 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Documentation/ABI/stable/sysfs-fs-orangefs:
+ *
+ * What:		/sys/fs/orangefs/perf_counter_reset
+ * Date:		June 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			echo a 0 or a 1 into perf_counter_reset to
+ * 			reset all the counters in
+ * 			/sys/fs/orangefs/perf_counters
+ * 			except ones with PINT_PERF_PRESERVE set.
+ *
+ *
+ * What:		/sys/fs/orangefs/perf_counters/...
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Counters and settings for various caches.
+ * 			Read only.
+ *
+ *
+ * What:		/sys/fs/orangefs/perf_time_interval_secs
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ *			Length of perf counter intervals in
+ *			seconds.
+ *
+ *
+ * What:		/sys/fs/orangefs/perf_history_size
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			The perf_counters cache statistics have N, or
+ * 			perf_history_size, samples. The default is
+ * 			one.
+ *
+ *			Every perf_time_interval_secs the (first)
+ *			samples are reset.
+ *
+ *			If N is greater than one, the "current" set
+ *			of samples is reset, and the samples from the
+ *			other N-1 intervals remain available.
+ *
+ *
+ * What:		/sys/fs/orangefs/op_timeout_secs
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ *			Service operation timeout in seconds.
+ *
+ *
+ * What:		/sys/fs/orangefs/slot_timeout_secs
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ *			"Slot" timeout in seconds. A "slot"
+ *			is an indexed buffer in the shared
+ *			memory segment used for communication
+ *			between the kernel module and userspace.
+ *			Slots are requested and waited for,
+ *			the wait times out after slot_timeout_secs.
+ *
+ * What:		/sys/fs/orangefs/cache_timeout_msecs
+ * Date:		Mar 2018
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Time in milliseconds between which
+ *			orangefs_revalidate_mapping will invalidate the page
+ *			cache.
+ *
+ * What:		/sys/fs/orangefs/dcache_timeout_msecs
+ * Date:		Jul 2016
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Time lookup is valid in milliseconds.
+ *
+ * What:		/sys/fs/orangefs/getattr_timeout_msecs
+ * Date:		Jul 2016
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Time getattr is valid in milliseconds.
+ *
+ * What:		/sys/fs/orangefs/readahead_count
+ * Date:		Aug 2016
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Readahead cache buffer count.
+ *
+ * What:		/sys/fs/orangefs/readahead_size
+ * Date:		Aug 2016
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Readahead cache buffer size.
+ *
+ * What:		/sys/fs/orangefs/readahead_count_size
+ * Date:		Aug 2016
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Readahead cache buffer count and size.
+ *
+ * What:		/sys/fs/orangefs/readahead_readcnt
+ * Date:		Jan 2017
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ *			Number of buffers (in multiples of readahead_size)
+ *			which can be read ahead for a single file at once.
+ *
+ * What:		/sys/fs/orangefs/acache/...
+ * Date:		Jun 2015
+ * Contact:		Martin Brandenburg <martin@omnibond.com>
+ * Description:
+ * 			Attribute cache configurable settings.
+ *
+ *
+ * What:		/sys/fs/orangefs/ncache/...
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Name cache configurable settings.
+ *
+ *
+ * What:		/sys/fs/orangefs/capcache/...
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Capability cache configurable settings.
+ *
+ *
+ * What:		/sys/fs/orangefs/ccache/...
+ * Date:		Jun 2015
+ * Contact:		Mike Marshall <hubcap@omnibond.com>
+ * Description:
+ * 			Credential cache configurable settings.
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/kobject.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-sysfs.h"
+
+#define ORANGEFS_KOBJ_ID "orangefs"
+#define ACACHE_KOBJ_ID "acache"
+#define CAPCACHE_KOBJ_ID "capcache"
+#define CCACHE_KOBJ_ID "ccache"
+#define NCACHE_KOBJ_ID "ncache"
+#define PC_KOBJ_ID "pc"
+#define STATS_KOBJ_ID "stats"
+
+/*
+ * Every item calls orangefs_attr_show and orangefs_attr_store through
+ * orangefs_sysfs_ops. They look at the orangefs_attributes further below to
+ * call one of sysfs_int_show, sysfs_int_store, sysfs_service_op_show, or
+ * sysfs_service_op_store.
+ */
+
+struct orangefs_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct kobject *kobj,
+			struct orangefs_attribute *attr,
+			char *buf);
+	ssize_t (*store)(struct kobject *kobj,
+			 struct orangefs_attribute *attr,
+			 const char *buf,
+			 size_t count);
+};
+
+static ssize_t orangefs_attr_show(struct kobject *kobj,
+				  struct attribute *attr,
+				  char *buf)
+{
+	struct orangefs_attribute *attribute;
+
+	attribute = container_of(attr, struct orangefs_attribute, attr);
+	if (!attribute->show)
+		return -EIO;
+	return attribute->show(kobj, attribute, buf);
+}
+
+static ssize_t orangefs_attr_store(struct kobject *kobj,
+				   struct attribute *attr,
+				   const char *buf,
+				   size_t len)
+{
+	struct orangefs_attribute *attribute;
+
+	if (!strcmp(kobj->name, PC_KOBJ_ID) ||
+	    !strcmp(kobj->name, STATS_KOBJ_ID))
+		return -EPERM;
+
+	attribute = container_of(attr, struct orangefs_attribute, attr);
+	if (!attribute->store)
+		return -EIO;
+	return attribute->store(kobj, attribute, buf, len);
+}
+
+static const struct sysfs_ops orangefs_sysfs_ops = {
+	.show = orangefs_attr_show,
+	.store = orangefs_attr_store,
+};
+
+static ssize_t sysfs_int_show(struct kobject *kobj,
+    struct orangefs_attribute *attr, char *buf)
+{
+	int rc = -EIO;
+
+	gossip_debug(GOSSIP_SYSFS_DEBUG, "sysfs_int_show: id:%s:\n",
+	    kobj->name);
+
+	if (!strcmp(kobj->name, ORANGEFS_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "op_timeout_secs")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%d\n",
+				       op_timeout_secs);
+			goto out;
+		} else if (!strcmp(attr->attr.name,
+				   "slot_timeout_secs")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%d\n",
+				       slot_timeout_secs);
+			goto out;
+		} else if (!strcmp(attr->attr.name,
+				   "cache_timeout_msecs")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%d\n",
+				       orangefs_cache_timeout_msecs);
+			goto out;
+		} else if (!strcmp(attr->attr.name,
+				   "dcache_timeout_msecs")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%d\n",
+				       orangefs_dcache_timeout_msecs);
+			goto out;
+		} else if (!strcmp(attr->attr.name,
+				   "getattr_timeout_msecs")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%d\n",
+				       orangefs_getattr_timeout_msecs);
+			goto out;
+		} else {
+			goto out;
+		}
+
+	} else if (!strcmp(kobj->name, STATS_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "reads")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%lu\n",
+				       orangefs_stats.reads);
+			goto out;
+		} else if (!strcmp(attr->attr.name, "writes")) {
+			rc = scnprintf(buf,
+				       PAGE_SIZE,
+				       "%lu\n",
+				       orangefs_stats.writes);
+			goto out;
+		} else {
+			goto out;
+		}
+	}
+
+out:
+
+	return rc;
+}
+
+static ssize_t sysfs_int_store(struct kobject *kobj,
+    struct orangefs_attribute *attr, const char *buf, size_t count)
+{
+	int rc = 0;
+
+	gossip_debug(GOSSIP_SYSFS_DEBUG,
+		     "sysfs_int_store: start attr->attr.name:%s: buf:%s:\n",
+		     attr->attr.name, buf);
+
+	if (!strcmp(attr->attr.name, "op_timeout_secs")) {
+		rc = kstrtoint(buf, 0, &op_timeout_secs);
+		goto out;
+	} else if (!strcmp(attr->attr.name, "slot_timeout_secs")) {
+		rc = kstrtoint(buf, 0, &slot_timeout_secs);
+		goto out;
+	} else if (!strcmp(attr->attr.name, "cache_timeout_msecs")) {
+		rc = kstrtoint(buf, 0, &orangefs_cache_timeout_msecs);
+		goto out;
+	} else if (!strcmp(attr->attr.name, "dcache_timeout_msecs")) {
+		rc = kstrtoint(buf, 0, &orangefs_dcache_timeout_msecs);
+		goto out;
+	} else if (!strcmp(attr->attr.name, "getattr_timeout_msecs")) {
+		rc = kstrtoint(buf, 0, &orangefs_getattr_timeout_msecs);
+		goto out;
+	} else {
+		goto out;
+	}
+
+out:
+	if (rc)
+		rc = -EINVAL;
+	else
+		rc = count;
+
+	return rc;
+}
+
+/*
+ * obtain attribute values from userspace with a service operation.
+ */
+static ssize_t sysfs_service_op_show(struct kobject *kobj,
+    struct orangefs_attribute *attr, char *buf)
+{
+	struct orangefs_kernel_op_s *new_op = NULL;
+	int rc = 0;
+	char *ser_op_type = NULL;
+	__u32 op_alloc_type;
+
+	gossip_debug(GOSSIP_SYSFS_DEBUG,
+		     "sysfs_service_op_show: id:%s:\n",
+		     kobj->name);
+
+	if (strcmp(kobj->name, PC_KOBJ_ID))
+		op_alloc_type = ORANGEFS_VFS_OP_PARAM;
+	else
+		op_alloc_type = ORANGEFS_VFS_OP_PERF_COUNT;
+
+	new_op = op_alloc(op_alloc_type);
+	if (!new_op)
+		return -ENOMEM;
+
+	/* Can't do a service_operation if the client is not running... */
+	rc = is_daemon_in_service();
+	if (rc) {
+		pr_info_ratelimited("%s: Client not running :%d:\n",
+			__func__,
+			is_daemon_in_service());
+		goto out;
+	}
+
+	if (strcmp(kobj->name, PC_KOBJ_ID))
+		new_op->upcall.req.param.type = ORANGEFS_PARAM_REQUEST_GET;
+
+	if (!strcmp(kobj->name, ORANGEFS_KOBJ_ID)) {
+		/* Drop unsupported requests first. */
+		if (!(orangefs_features & ORANGEFS_FEATURE_READAHEAD) &&
+		    (!strcmp(attr->attr.name, "readahead_count") ||
+		    !strcmp(attr->attr.name, "readahead_size") ||
+		    !strcmp(attr->attr.name, "readahead_count_size") ||
+		    !strcmp(attr->attr.name, "readahead_readcnt"))) {
+			rc = -EINVAL;
+			goto out;
+		}
+
+		if (!strcmp(attr->attr.name, "perf_history_size"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_PERF_HISTORY_SIZE;
+		else if (!strcmp(attr->attr.name,
+				 "perf_time_interval_secs"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_PERF_TIME_INTERVAL_SECS;
+		else if (!strcmp(attr->attr.name,
+				 "perf_counter_reset"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_PERF_RESET;
+
+		else if (!strcmp(attr->attr.name,
+				 "readahead_count"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT;
+
+		else if (!strcmp(attr->attr.name,
+				 "readahead_size"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_SIZE;
+
+		else if (!strcmp(attr->attr.name,
+				 "readahead_count_size"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT_SIZE;
+
+		else if (!strcmp(attr->attr.name,
+				 "readahead_readcnt"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_READCNT;
+	} else if (!strcmp(kobj->name, ACACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "timeout_msecs"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_ACACHE_TIMEOUT_MSECS;
+
+		if (!strcmp(attr->attr.name, "hard_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_ACACHE_HARD_LIMIT;
+
+		if (!strcmp(attr->attr.name, "soft_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_ACACHE_SOFT_LIMIT;
+
+		if (!strcmp(attr->attr.name, "reclaim_percentage"))
+			new_op->upcall.req.param.op =
+			  ORANGEFS_PARAM_REQUEST_OP_ACACHE_RECLAIM_PERCENTAGE;
+
+	} else if (!strcmp(kobj->name, CAPCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "timeout_secs"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_TIMEOUT_SECS;
+
+		if (!strcmp(attr->attr.name, "hard_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_HARD_LIMIT;
+
+		if (!strcmp(attr->attr.name, "soft_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_SOFT_LIMIT;
+
+		if (!strcmp(attr->attr.name, "reclaim_percentage"))
+			new_op->upcall.req.param.op =
+			  ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_RECLAIM_PERCENTAGE;
+
+	} else if (!strcmp(kobj->name, CCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "timeout_secs"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CCACHE_TIMEOUT_SECS;
+
+		if (!strcmp(attr->attr.name, "hard_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CCACHE_HARD_LIMIT;
+
+		if (!strcmp(attr->attr.name, "soft_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_CCACHE_SOFT_LIMIT;
+
+		if (!strcmp(attr->attr.name, "reclaim_percentage"))
+			new_op->upcall.req.param.op =
+			  ORANGEFS_PARAM_REQUEST_OP_CCACHE_RECLAIM_PERCENTAGE;
+
+	} else if (!strcmp(kobj->name, NCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "timeout_msecs"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_NCACHE_TIMEOUT_MSECS;
+
+		if (!strcmp(attr->attr.name, "hard_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_NCACHE_HARD_LIMIT;
+
+		if (!strcmp(attr->attr.name, "soft_limit"))
+			new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_NCACHE_SOFT_LIMIT;
+
+		if (!strcmp(attr->attr.name, "reclaim_percentage"))
+			new_op->upcall.req.param.op =
+			  ORANGEFS_PARAM_REQUEST_OP_NCACHE_RECLAIM_PERCENTAGE;
+
+	} else if (!strcmp(kobj->name, PC_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, ACACHE_KOBJ_ID))
+			new_op->upcall.req.perf_count.type =
+				ORANGEFS_PERF_COUNT_REQUEST_ACACHE;
+
+		if (!strcmp(attr->attr.name, CAPCACHE_KOBJ_ID))
+			new_op->upcall.req.perf_count.type =
+				ORANGEFS_PERF_COUNT_REQUEST_CAPCACHE;
+
+		if (!strcmp(attr->attr.name, NCACHE_KOBJ_ID))
+			new_op->upcall.req.perf_count.type =
+				ORANGEFS_PERF_COUNT_REQUEST_NCACHE;
+
+	} else {
+		gossip_err("sysfs_service_op_show: unknown kobj_id:%s:\n",
+			   kobj->name);
+		rc = -EINVAL;
+		goto out;
+	}
+
+
+	if (strcmp(kobj->name, PC_KOBJ_ID))
+		ser_op_type = "orangefs_param";
+	else
+		ser_op_type = "orangefs_perf_count";
+
+	/*
+	 * The service_operation will return an errno return code on
+	 * error, and zero on success.
+	 */
+	rc = service_operation(new_op, ser_op_type, ORANGEFS_OP_INTERRUPTIBLE);
+
+out:
+	if (!rc) {
+		if (strcmp(kobj->name, PC_KOBJ_ID)) {
+			if (new_op->upcall.req.param.op ==
+			    ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT_SIZE) {
+				rc = scnprintf(buf, PAGE_SIZE, "%d %d\n",
+				    (int)new_op->downcall.resp.param.u.
+				    value32[0],
+				    (int)new_op->downcall.resp.param.u.
+				    value32[1]);
+			} else {
+				rc = scnprintf(buf, PAGE_SIZE, "%d\n",
+				    (int)new_op->downcall.resp.param.u.value64);
+			}
+		} else {
+			rc = scnprintf(
+				buf,
+				PAGE_SIZE,
+				"%s",
+				new_op->downcall.resp.perf_count.buffer);
+		}
+	}
+
+	op_release(new_op);
+
+	return rc;
+
+}
+
+/*
+ * pass attribute values back to userspace with a service operation.
+ *
+ * We have to do a memory allocation, an sscanf and a service operation.
+ * And we have to evaluate what the user entered, to make sure the
+ * value is within the range supported by the attribute. So, there's
+ * a lot of return code checking and mapping going on here.
+ *
+ * We want to return 1 if we think everything went OK, and
+ * EINVAL if not.
+ */
+static ssize_t sysfs_service_op_store(struct kobject *kobj,
+    struct orangefs_attribute *attr, const char *buf, size_t count)
+{
+	struct orangefs_kernel_op_s *new_op = NULL;
+	int val = 0;
+	int rc = 0;
+
+	gossip_debug(GOSSIP_SYSFS_DEBUG,
+		     "sysfs_service_op_store: id:%s:\n",
+		     kobj->name);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_PARAM);
+	if (!new_op)
+		return -EINVAL; /* sic */
+
+	/* Can't do a service_operation if the client is not running... */
+	rc = is_daemon_in_service();
+	if (rc) {
+		pr_info("%s: Client not running :%d:\n",
+			__func__,
+			is_daemon_in_service());
+		goto out;
+	}
+
+	/*
+	 * The value we want to send back to userspace is in buf, unless this
+	 * there are two parameters, which is specially handled below.
+	 */
+	if (strcmp(kobj->name, ORANGEFS_KOBJ_ID) ||
+	    strcmp(attr->attr.name, "readahead_count_size")) {
+		rc = kstrtoint(buf, 0, &val);
+		if (rc)
+			goto out;
+	}
+
+	new_op->upcall.req.param.type = ORANGEFS_PARAM_REQUEST_SET;
+
+	if (!strcmp(kobj->name, ORANGEFS_KOBJ_ID)) {
+		/* Drop unsupported requests first. */
+		if (!(orangefs_features & ORANGEFS_FEATURE_READAHEAD) &&
+		    (!strcmp(attr->attr.name, "readahead_count") ||
+		    !strcmp(attr->attr.name, "readahead_size") ||
+		    !strcmp(attr->attr.name, "readahead_count_size") ||
+		    !strcmp(attr->attr.name, "readahead_readcnt"))) {
+			rc = -EINVAL;
+			goto out;
+		}
+
+		if (!strcmp(attr->attr.name, "perf_history_size")) {
+			if (val > 0) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_PERF_HISTORY_SIZE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "perf_time_interval_secs")) {
+			if (val > 0) {
+				new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_PERF_TIME_INTERVAL_SECS;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "perf_counter_reset")) {
+			if ((val == 0) || (val == 1)) {
+				new_op->upcall.req.param.op =
+					ORANGEFS_PARAM_REQUEST_OP_PERF_RESET;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "readahead_count")) {
+			if ((val >= 0)) {
+				new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "readahead_size")) {
+			if ((val >= 0)) {
+				new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_SIZE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "readahead_count_size")) {
+			int val1, val2;
+			rc = sscanf(buf, "%d %d", &val1, &val2);
+			if (rc < 2) {
+				rc = 0;
+				goto out;
+			}
+			if ((val1 >= 0) && (val2 >= 0)) {
+				new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT_SIZE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+			new_op->upcall.req.param.u.value32[0] = val1;
+			new_op->upcall.req.param.u.value32[1] = val2;
+			goto value_set;
+		} else if (!strcmp(attr->attr.name,
+				   "readahead_readcnt")) {
+			if ((val >= 0)) {
+				new_op->upcall.req.param.op =
+				ORANGEFS_PARAM_REQUEST_OP_READAHEAD_READCNT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		}
+
+	} else if (!strcmp(kobj->name, ACACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "hard_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_ACACHE_HARD_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "soft_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_ACACHE_SOFT_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "reclaim_percentage")) {
+			if ((val > -1) && (val < 101)) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_ACACHE_RECLAIM_PERCENTAGE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "timeout_msecs")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_ACACHE_TIMEOUT_MSECS;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		}
+
+	} else if (!strcmp(kobj->name, CAPCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "hard_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_HARD_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "soft_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_SOFT_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "reclaim_percentage")) {
+			if ((val > -1) && (val < 101)) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_RECLAIM_PERCENTAGE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "timeout_secs")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_TIMEOUT_SECS;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		}
+
+	} else if (!strcmp(kobj->name, CCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "hard_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CCACHE_HARD_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "soft_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CCACHE_SOFT_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "reclaim_percentage")) {
+			if ((val > -1) && (val < 101)) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CCACHE_RECLAIM_PERCENTAGE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "timeout_secs")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_CCACHE_TIMEOUT_SECS;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		}
+
+	} else if (!strcmp(kobj->name, NCACHE_KOBJ_ID)) {
+		if (!strcmp(attr->attr.name, "hard_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_NCACHE_HARD_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "soft_limit")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_NCACHE_SOFT_LIMIT;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name,
+				   "reclaim_percentage")) {
+			if ((val > -1) && (val < 101)) {
+				new_op->upcall.req.param.op =
+					ORANGEFS_PARAM_REQUEST_OP_NCACHE_RECLAIM_PERCENTAGE;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		} else if (!strcmp(attr->attr.name, "timeout_msecs")) {
+			if (val > -1) {
+				new_op->upcall.req.param.op =
+				  ORANGEFS_PARAM_REQUEST_OP_NCACHE_TIMEOUT_MSECS;
+			} else {
+				rc = 0;
+				goto out;
+			}
+		}
+
+	} else {
+		gossip_err("sysfs_service_op_store: unknown kobj_id:%s:\n",
+			   kobj->name);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	new_op->upcall.req.param.u.value64 = val;
+value_set:
+
+	/*
+	 * The service_operation will return a errno return code on
+	 * error, and zero on success.
+	 */
+	rc = service_operation(new_op, "orangefs_param", ORANGEFS_OP_INTERRUPTIBLE);
+
+	if (rc < 0) {
+		gossip_err("sysfs_service_op_store: service op returned:%d:\n",
+			rc);
+		rc = 0;
+	} else {
+		rc = count;
+	}
+
+out:
+	op_release(new_op);
+
+	if (rc == -ENOMEM || rc == 0)
+		rc = -EINVAL;
+
+	return rc;
+}
+
+static struct orangefs_attribute op_timeout_secs_attribute =
+	__ATTR(op_timeout_secs, 0664, sysfs_int_show, sysfs_int_store);
+
+static struct orangefs_attribute slot_timeout_secs_attribute =
+	__ATTR(slot_timeout_secs, 0664, sysfs_int_show, sysfs_int_store);
+
+static struct orangefs_attribute cache_timeout_msecs_attribute =
+	__ATTR(cache_timeout_msecs, 0664, sysfs_int_show, sysfs_int_store);
+
+static struct orangefs_attribute dcache_timeout_msecs_attribute =
+	__ATTR(dcache_timeout_msecs, 0664, sysfs_int_show, sysfs_int_store);
+
+static struct orangefs_attribute getattr_timeout_msecs_attribute =
+	__ATTR(getattr_timeout_msecs, 0664, sysfs_int_show, sysfs_int_store);
+
+static struct orangefs_attribute readahead_count_attribute =
+	__ATTR(readahead_count, 0664, sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute readahead_size_attribute =
+	__ATTR(readahead_size, 0664, sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute readahead_count_size_attribute =
+	__ATTR(readahead_count_size, 0664, sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute readahead_readcnt_attribute =
+	__ATTR(readahead_readcnt, 0664, sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute perf_counter_reset_attribute =
+	__ATTR(perf_counter_reset,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute perf_history_size_attribute =
+	__ATTR(perf_history_size,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute perf_time_interval_secs_attribute =
+	__ATTR(perf_time_interval_secs,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct attribute *orangefs_default_attrs[] = {
+	&op_timeout_secs_attribute.attr,
+	&slot_timeout_secs_attribute.attr,
+	&cache_timeout_msecs_attribute.attr,
+	&dcache_timeout_msecs_attribute.attr,
+	&getattr_timeout_msecs_attribute.attr,
+	&readahead_count_attribute.attr,
+	&readahead_size_attribute.attr,
+	&readahead_count_size_attribute.attr,
+	&readahead_readcnt_attribute.attr,
+	&perf_counter_reset_attribute.attr,
+	&perf_history_size_attribute.attr,
+	&perf_time_interval_secs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(orangefs_default);
+
+static struct kobject *orangefs_obj;
+
+static void orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(orangefs_obj);
+	orangefs_obj = NULL;
+}
+
+static struct kobj_type orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = orangefs_default_groups,
+	.release = orangefs_obj_release,
+};
+
+static struct orangefs_attribute acache_hard_limit_attribute =
+	__ATTR(hard_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute acache_reclaim_percent_attribute =
+	__ATTR(reclaim_percentage,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute acache_soft_limit_attribute =
+	__ATTR(soft_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute acache_timeout_msecs_attribute =
+	__ATTR(timeout_msecs,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct attribute *acache_orangefs_default_attrs[] = {
+	&acache_hard_limit_attribute.attr,
+	&acache_reclaim_percent_attribute.attr,
+	&acache_soft_limit_attribute.attr,
+	&acache_timeout_msecs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(acache_orangefs_default);
+
+static struct kobject *acache_orangefs_obj;
+
+static void acache_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(acache_orangefs_obj);
+	acache_orangefs_obj = NULL;
+}
+
+static struct kobj_type acache_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = acache_orangefs_default_groups,
+	.release = acache_orangefs_obj_release,
+};
+
+static struct orangefs_attribute capcache_hard_limit_attribute =
+	__ATTR(hard_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute capcache_reclaim_percent_attribute =
+	__ATTR(reclaim_percentage,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute capcache_soft_limit_attribute =
+	__ATTR(soft_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute capcache_timeout_secs_attribute =
+	__ATTR(timeout_secs,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct attribute *capcache_orangefs_default_attrs[] = {
+	&capcache_hard_limit_attribute.attr,
+	&capcache_reclaim_percent_attribute.attr,
+	&capcache_soft_limit_attribute.attr,
+	&capcache_timeout_secs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(capcache_orangefs_default);
+
+static struct kobject *capcache_orangefs_obj;
+
+static void capcache_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(capcache_orangefs_obj);
+	capcache_orangefs_obj = NULL;
+}
+
+static struct kobj_type capcache_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = capcache_orangefs_default_groups,
+	.release = capcache_orangefs_obj_release,
+};
+
+static struct orangefs_attribute ccache_hard_limit_attribute =
+	__ATTR(hard_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ccache_reclaim_percent_attribute =
+	__ATTR(reclaim_percentage,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ccache_soft_limit_attribute =
+	__ATTR(soft_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ccache_timeout_secs_attribute =
+	__ATTR(timeout_secs,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct attribute *ccache_orangefs_default_attrs[] = {
+	&ccache_hard_limit_attribute.attr,
+	&ccache_reclaim_percent_attribute.attr,
+	&ccache_soft_limit_attribute.attr,
+	&ccache_timeout_secs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(ccache_orangefs_default);
+
+static struct kobject *ccache_orangefs_obj;
+
+static void ccache_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(ccache_orangefs_obj);
+	ccache_orangefs_obj = NULL;
+}
+
+static struct kobj_type ccache_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = ccache_orangefs_default_groups,
+	.release = ccache_orangefs_obj_release,
+};
+
+static struct orangefs_attribute ncache_hard_limit_attribute =
+	__ATTR(hard_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ncache_reclaim_percent_attribute =
+	__ATTR(reclaim_percentage,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ncache_soft_limit_attribute =
+	__ATTR(soft_limit,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct orangefs_attribute ncache_timeout_msecs_attribute =
+	__ATTR(timeout_msecs,
+	       0664,
+	       sysfs_service_op_show,
+	       sysfs_service_op_store);
+
+static struct attribute *ncache_orangefs_default_attrs[] = {
+	&ncache_hard_limit_attribute.attr,
+	&ncache_reclaim_percent_attribute.attr,
+	&ncache_soft_limit_attribute.attr,
+	&ncache_timeout_msecs_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(ncache_orangefs_default);
+
+static struct kobject *ncache_orangefs_obj;
+
+static void ncache_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(ncache_orangefs_obj);
+	ncache_orangefs_obj = NULL;
+}
+
+static struct kobj_type ncache_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = ncache_orangefs_default_groups,
+	.release = ncache_orangefs_obj_release,
+};
+
+static struct orangefs_attribute pc_acache_attribute =
+	__ATTR(acache,
+	       0664,
+	       sysfs_service_op_show,
+	       NULL);
+
+static struct orangefs_attribute pc_capcache_attribute =
+	__ATTR(capcache,
+	       0664,
+	       sysfs_service_op_show,
+	       NULL);
+
+static struct orangefs_attribute pc_ncache_attribute =
+	__ATTR(ncache,
+	       0664,
+	       sysfs_service_op_show,
+	       NULL);
+
+static struct attribute *pc_orangefs_default_attrs[] = {
+	&pc_acache_attribute.attr,
+	&pc_capcache_attribute.attr,
+	&pc_ncache_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(pc_orangefs_default);
+
+static struct kobject *pc_orangefs_obj;
+
+static void pc_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(pc_orangefs_obj);
+	pc_orangefs_obj = NULL;
+}
+
+static struct kobj_type pc_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = pc_orangefs_default_groups,
+	.release = pc_orangefs_obj_release,
+};
+
+static struct orangefs_attribute stats_reads_attribute =
+	__ATTR(reads,
+	       0664,
+	       sysfs_int_show,
+	       NULL);
+
+static struct orangefs_attribute stats_writes_attribute =
+	__ATTR(writes,
+	       0664,
+	       sysfs_int_show,
+	       NULL);
+
+static struct attribute *stats_orangefs_default_attrs[] = {
+	&stats_reads_attribute.attr,
+	&stats_writes_attribute.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(stats_orangefs_default);
+
+static struct kobject *stats_orangefs_obj;
+
+static void stats_orangefs_obj_release(struct kobject *kobj)
+{
+	kfree(stats_orangefs_obj);
+	stats_orangefs_obj = NULL;
+}
+
+static struct kobj_type stats_orangefs_ktype = {
+	.sysfs_ops = &orangefs_sysfs_ops,
+	.default_groups = stats_orangefs_default_groups,
+	.release = stats_orangefs_obj_release,
+};
+
+int orangefs_sysfs_init(void)
+{
+	int rc = -EINVAL;
+
+	gossip_debug(GOSSIP_SYSFS_DEBUG, "orangefs_sysfs_init: start\n");
+
+	/* create /sys/fs/orangefs. */
+	orangefs_obj = kzalloc(sizeof(*orangefs_obj), GFP_KERNEL);
+	if (!orangefs_obj)
+		goto out;
+
+	rc = kobject_init_and_add(orangefs_obj,
+				  &orangefs_ktype,
+				  fs_kobj,
+				  ORANGEFS_KOBJ_ID);
+
+	if (rc)
+		goto ofs_obj_bail;
+
+	kobject_uevent(orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/acache. */
+	acache_orangefs_obj = kzalloc(sizeof(*acache_orangefs_obj), GFP_KERNEL);
+	if (!acache_orangefs_obj) {
+		rc = -EINVAL;
+		goto ofs_obj_bail;
+	}
+
+	rc = kobject_init_and_add(acache_orangefs_obj,
+				  &acache_orangefs_ktype,
+				  orangefs_obj,
+				  ACACHE_KOBJ_ID);
+
+	if (rc)
+		goto acache_obj_bail;
+
+	kobject_uevent(acache_orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/capcache. */
+	capcache_orangefs_obj =
+		kzalloc(sizeof(*capcache_orangefs_obj), GFP_KERNEL);
+	if (!capcache_orangefs_obj) {
+		rc = -EINVAL;
+		goto acache_obj_bail;
+	}
+
+	rc = kobject_init_and_add(capcache_orangefs_obj,
+				  &capcache_orangefs_ktype,
+				  orangefs_obj,
+				  CAPCACHE_KOBJ_ID);
+	if (rc)
+		goto capcache_obj_bail;
+
+	kobject_uevent(capcache_orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/ccache. */
+	ccache_orangefs_obj =
+		kzalloc(sizeof(*ccache_orangefs_obj), GFP_KERNEL);
+	if (!ccache_orangefs_obj) {
+		rc = -EINVAL;
+		goto capcache_obj_bail;
+	}
+
+	rc = kobject_init_and_add(ccache_orangefs_obj,
+				  &ccache_orangefs_ktype,
+				  orangefs_obj,
+				  CCACHE_KOBJ_ID);
+	if (rc)
+		goto ccache_obj_bail;
+
+	kobject_uevent(ccache_orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/ncache. */
+	ncache_orangefs_obj = kzalloc(sizeof(*ncache_orangefs_obj), GFP_KERNEL);
+	if (!ncache_orangefs_obj) {
+		rc = -EINVAL;
+		goto ccache_obj_bail;
+	}
+
+	rc = kobject_init_and_add(ncache_orangefs_obj,
+				  &ncache_orangefs_ktype,
+				  orangefs_obj,
+				  NCACHE_KOBJ_ID);
+
+	if (rc)
+		goto ncache_obj_bail;
+
+	kobject_uevent(ncache_orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/perf_counters. */
+	pc_orangefs_obj = kzalloc(sizeof(*pc_orangefs_obj), GFP_KERNEL);
+	if (!pc_orangefs_obj) {
+		rc = -EINVAL;
+		goto ncache_obj_bail;
+	}
+
+	rc = kobject_init_and_add(pc_orangefs_obj,
+				  &pc_orangefs_ktype,
+				  orangefs_obj,
+				  "perf_counters");
+
+	if (rc)
+		goto pc_obj_bail;
+
+	kobject_uevent(pc_orangefs_obj, KOBJ_ADD);
+
+	/* create /sys/fs/orangefs/stats. */
+	stats_orangefs_obj = kzalloc(sizeof(*stats_orangefs_obj), GFP_KERNEL);
+	if (!stats_orangefs_obj) {
+		rc = -EINVAL;
+		goto pc_obj_bail;
+	}
+
+	rc = kobject_init_and_add(stats_orangefs_obj,
+				  &stats_orangefs_ktype,
+				  orangefs_obj,
+				  STATS_KOBJ_ID);
+
+	if (rc)
+		goto stats_obj_bail;
+
+	kobject_uevent(stats_orangefs_obj, KOBJ_ADD);
+	goto out;
+
+stats_obj_bail:
+		kobject_put(stats_orangefs_obj);
+pc_obj_bail:
+		kobject_put(pc_orangefs_obj);
+ncache_obj_bail:
+		kobject_put(ncache_orangefs_obj);
+ccache_obj_bail:
+		kobject_put(ccache_orangefs_obj);
+capcache_obj_bail:
+		kobject_put(capcache_orangefs_obj);
+acache_obj_bail:
+		kobject_put(acache_orangefs_obj);
+ofs_obj_bail:
+		kobject_put(orangefs_obj);
+out:
+	return rc;
+}
+
+void orangefs_sysfs_exit(void)
+{
+	gossip_debug(GOSSIP_SYSFS_DEBUG, "orangefs_sysfs_exit: start\n");
+	kobject_put(acache_orangefs_obj);
+	kobject_put(capcache_orangefs_obj);
+	kobject_put(ccache_orangefs_obj);
+	kobject_put(ncache_orangefs_obj);
+	kobject_put(pc_orangefs_obj);
+	kobject_put(stats_orangefs_obj);
+	kobject_put(orangefs_obj);
+}
diff --git a/fs/orangefs/orangefs-sysfs.h b/fs/orangefs/orangefs-sysfs.h
new file mode 100644
index 000000000..f0b76382d
--- /dev/null
+++ b/fs/orangefs/orangefs-sysfs.h
@@ -0,0 +1,2 @@
+extern int orangefs_sysfs_init(void);
+extern void orangefs_sysfs_exit(void);
diff --git a/fs/orangefs/orangefs-utils.c b/fs/orangefs/orangefs-utils.c
new file mode 100644
index 000000000..46b7dcff1
--- /dev/null
+++ b/fs/orangefs/orangefs-utils.c
@@ -0,0 +1,560 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * Copyright 2018 Omnibond Systems, L.L.C.
+ *
+ * See COPYING in top-level directory.
+ */
+#include <linux/kernel.h>
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-dev-proto.h"
+#include "orangefs-bufmap.h"
+
+__s32 fsid_of_op(struct orangefs_kernel_op_s *op)
+{
+	__s32 fsid = ORANGEFS_FS_ID_NULL;
+
+	if (op) {
+		switch (op->upcall.type) {
+		case ORANGEFS_VFS_OP_FILE_IO:
+			fsid = op->upcall.req.io.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_LOOKUP:
+			fsid = op->upcall.req.lookup.parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_CREATE:
+			fsid = op->upcall.req.create.parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_GETATTR:
+			fsid = op->upcall.req.getattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_REMOVE:
+			fsid = op->upcall.req.remove.parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_MKDIR:
+			fsid = op->upcall.req.mkdir.parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_READDIR:
+			fsid = op->upcall.req.readdir.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_SETATTR:
+			fsid = op->upcall.req.setattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_SYMLINK:
+			fsid = op->upcall.req.sym.parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_RENAME:
+			fsid = op->upcall.req.rename.old_parent_refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_STATFS:
+			fsid = op->upcall.req.statfs.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_TRUNCATE:
+			fsid = op->upcall.req.truncate.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_RA_FLUSH:
+			fsid = op->upcall.req.ra_cache_flush.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_FS_UMOUNT:
+			fsid = op->upcall.req.fs_umount.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_GETXATTR:
+			fsid = op->upcall.req.getxattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_SETXATTR:
+			fsid = op->upcall.req.setxattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_LISTXATTR:
+			fsid = op->upcall.req.listxattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_REMOVEXATTR:
+			fsid = op->upcall.req.removexattr.refn.fs_id;
+			break;
+		case ORANGEFS_VFS_OP_FSYNC:
+			fsid = op->upcall.req.fsync.refn.fs_id;
+			break;
+		default:
+			break;
+		}
+	}
+	return fsid;
+}
+
+static int orangefs_inode_flags(struct ORANGEFS_sys_attr_s *attrs)
+{
+	int flags = 0;
+	if (attrs->flags & ORANGEFS_IMMUTABLE_FL)
+		flags |= S_IMMUTABLE;
+	else
+		flags &= ~S_IMMUTABLE;
+	if (attrs->flags & ORANGEFS_APPEND_FL)
+		flags |= S_APPEND;
+	else
+		flags &= ~S_APPEND;
+	if (attrs->flags & ORANGEFS_NOATIME_FL)
+		flags |= S_NOATIME;
+	else
+		flags &= ~S_NOATIME;
+	return flags;
+}
+
+static int orangefs_inode_perms(struct ORANGEFS_sys_attr_s *attrs)
+{
+	int perm_mode = 0;
+
+	if (attrs->perms & ORANGEFS_O_EXECUTE)
+		perm_mode |= S_IXOTH;
+	if (attrs->perms & ORANGEFS_O_WRITE)
+		perm_mode |= S_IWOTH;
+	if (attrs->perms & ORANGEFS_O_READ)
+		perm_mode |= S_IROTH;
+
+	if (attrs->perms & ORANGEFS_G_EXECUTE)
+		perm_mode |= S_IXGRP;
+	if (attrs->perms & ORANGEFS_G_WRITE)
+		perm_mode |= S_IWGRP;
+	if (attrs->perms & ORANGEFS_G_READ)
+		perm_mode |= S_IRGRP;
+
+	if (attrs->perms & ORANGEFS_U_EXECUTE)
+		perm_mode |= S_IXUSR;
+	if (attrs->perms & ORANGEFS_U_WRITE)
+		perm_mode |= S_IWUSR;
+	if (attrs->perms & ORANGEFS_U_READ)
+		perm_mode |= S_IRUSR;
+
+	if (attrs->perms & ORANGEFS_G_SGID)
+		perm_mode |= S_ISGID;
+	if (attrs->perms & ORANGEFS_U_SUID)
+		perm_mode |= S_ISUID;
+
+	return perm_mode;
+}
+
+/*
+ * NOTE: in kernel land, we never use the sys_attr->link_target for
+ * anything, so don't bother copying it into the sys_attr object here.
+ */
+static inline void copy_attributes_from_inode(struct inode *inode,
+    struct ORANGEFS_sys_attr_s *attrs)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	attrs->mask = 0;
+	if (orangefs_inode->attr_valid & ATTR_UID) {
+		attrs->owner = from_kuid(&init_user_ns, inode->i_uid);
+		attrs->mask |= ORANGEFS_ATTR_SYS_UID;
+		gossip_debug(GOSSIP_UTILS_DEBUG, "(UID) %d\n", attrs->owner);
+	}
+	if (orangefs_inode->attr_valid & ATTR_GID) {
+		attrs->group = from_kgid(&init_user_ns, inode->i_gid);
+		attrs->mask |= ORANGEFS_ATTR_SYS_GID;
+		gossip_debug(GOSSIP_UTILS_DEBUG, "(GID) %d\n", attrs->group);
+	}
+
+	if (orangefs_inode->attr_valid & ATTR_ATIME) {
+		attrs->mask |= ORANGEFS_ATTR_SYS_ATIME;
+		if (orangefs_inode->attr_valid & ATTR_ATIME_SET) {
+			attrs->atime = (time64_t)inode->i_atime.tv_sec;
+			attrs->mask |= ORANGEFS_ATTR_SYS_ATIME_SET;
+		}
+	}
+	if (orangefs_inode->attr_valid & ATTR_MTIME) {
+		attrs->mask |= ORANGEFS_ATTR_SYS_MTIME;
+		if (orangefs_inode->attr_valid & ATTR_MTIME_SET) {
+			attrs->mtime = (time64_t)inode->i_mtime.tv_sec;
+			attrs->mask |= ORANGEFS_ATTR_SYS_MTIME_SET;
+		}
+	}
+	if (orangefs_inode->attr_valid & ATTR_CTIME)
+		attrs->mask |= ORANGEFS_ATTR_SYS_CTIME;
+
+	/*
+	 * ORANGEFS cannot set size with a setattr operation. Probably not
+	 * likely to be requested through the VFS, but just in case, don't
+	 * worry about ATTR_SIZE
+	 */
+
+	if (orangefs_inode->attr_valid & ATTR_MODE) {
+		attrs->perms = ORANGEFS_util_translate_mode(inode->i_mode);
+		attrs->mask |= ORANGEFS_ATTR_SYS_PERM;
+	}
+}
+
+static int orangefs_inode_type(enum orangefs_ds_type objtype)
+{
+	if (objtype == ORANGEFS_TYPE_METAFILE)
+		return S_IFREG;
+	else if (objtype == ORANGEFS_TYPE_DIRECTORY)
+		return S_IFDIR;
+	else if (objtype == ORANGEFS_TYPE_SYMLINK)
+		return S_IFLNK;
+	else
+		return -1;
+}
+
+static void orangefs_make_bad_inode(struct inode *inode)
+{
+	if (is_root_handle(inode)) {
+		/*
+		 * if this occurs, the pvfs2-client-core was killed but we
+		 * can't afford to lose the inode operations and such
+		 * associated with the root handle in any case.
+		 */
+		gossip_debug(GOSSIP_UTILS_DEBUG,
+			     "*** NOT making bad root inode %pU\n",
+			     get_khandle_from_ino(inode));
+	} else {
+		gossip_debug(GOSSIP_UTILS_DEBUG,
+			     "*** making bad inode %pU\n",
+			     get_khandle_from_ino(inode));
+		make_bad_inode(inode);
+	}
+}
+
+static int orangefs_inode_is_stale(struct inode *inode,
+    struct ORANGEFS_sys_attr_s *attrs, char *link_target)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	int type = orangefs_inode_type(attrs->objtype);
+	/*
+	 * If the inode type or symlink target have changed then this
+	 * inode is stale.
+	 */
+	if (type == -1 || inode_wrong_type(inode, type)) {
+		orangefs_make_bad_inode(inode);
+		return 1;
+	}
+	if (type == S_IFLNK && strncmp(orangefs_inode->link_target,
+	    link_target, ORANGEFS_NAME_MAX)) {
+		orangefs_make_bad_inode(inode);
+		return 1;
+	}
+	return 0;
+}
+
+int orangefs_inode_getattr(struct inode *inode, int flags)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	loff_t inode_size;
+	int ret, type;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: called on inode %pU flags %d\n",
+	    __func__, get_khandle_from_ino(inode), flags);
+
+again:
+	spin_lock(&inode->i_lock);
+	/* Must have all the attributes in the mask and be within cache time. */
+	if ((!flags && time_before(jiffies, orangefs_inode->getattr_time)) ||
+	    orangefs_inode->attr_valid || inode->i_state & I_DIRTY_PAGES) {
+		if (orangefs_inode->attr_valid) {
+			spin_unlock(&inode->i_lock);
+			write_inode_now(inode, 1);
+			goto again;
+		}
+		spin_unlock(&inode->i_lock);
+		return 0;
+	}
+	spin_unlock(&inode->i_lock);
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_GETATTR);
+	if (!new_op)
+		return -ENOMEM;
+	new_op->upcall.req.getattr.refn = orangefs_inode->refn;
+	/*
+	 * Size is the hardest attribute to get.  The incremental cost of any
+	 * other attribute is essentially zero.
+	 */
+	if (flags)
+		new_op->upcall.req.getattr.mask = ORANGEFS_ATTR_SYS_ALL_NOHINT;
+	else
+		new_op->upcall.req.getattr.mask =
+		    ORANGEFS_ATTR_SYS_ALL_NOHINT & ~ORANGEFS_ATTR_SYS_SIZE;
+
+	ret = service_operation(new_op, __func__,
+	    get_interruptible_flag(inode));
+	if (ret != 0)
+		goto out;
+
+again2:
+	spin_lock(&inode->i_lock);
+	/* Must have all the attributes in the mask and be within cache time. */
+	if ((!flags && time_before(jiffies, orangefs_inode->getattr_time)) ||
+	    orangefs_inode->attr_valid || inode->i_state & I_DIRTY_PAGES) {
+		if (orangefs_inode->attr_valid) {
+			spin_unlock(&inode->i_lock);
+			write_inode_now(inode, 1);
+			goto again2;
+		}
+		if (inode->i_state & I_DIRTY_PAGES) {
+			ret = 0;
+			goto out_unlock;
+		}
+		gossip_debug(GOSSIP_UTILS_DEBUG, "%s: in cache or dirty\n",
+		    __func__);
+		ret = 0;
+		goto out_unlock;
+	}
+
+	if (!(flags & ORANGEFS_GETATTR_NEW)) {
+		ret = orangefs_inode_is_stale(inode,
+		    &new_op->downcall.resp.getattr.attributes,
+		    new_op->downcall.resp.getattr.link_target);
+		if (ret) {
+			ret = -ESTALE;
+			goto out_unlock;
+		}
+	}
+
+	type = orangefs_inode_type(new_op->
+	    downcall.resp.getattr.attributes.objtype);
+	switch (type) {
+	case S_IFREG:
+		inode->i_flags = orangefs_inode_flags(&new_op->
+		    downcall.resp.getattr.attributes);
+		if (flags) {
+			inode_size = (loff_t)new_op->
+			    downcall.resp.getattr.attributes.size;
+			inode->i_size = inode_size;
+			inode->i_blkbits = ffs(new_op->downcall.resp.getattr.
+			    attributes.blksize);
+			inode->i_bytes = inode_size;
+			inode->i_blocks =
+			    (inode_size + 512 - inode_size % 512)/512;
+		}
+		break;
+	case S_IFDIR:
+		if (flags) {
+			inode->i_size = PAGE_SIZE;
+			inode_set_bytes(inode, inode->i_size);
+		}
+		set_nlink(inode, 1);
+		break;
+	case S_IFLNK:
+		if (flags & ORANGEFS_GETATTR_NEW) {
+			inode->i_size = (loff_t)strlen(new_op->
+			    downcall.resp.getattr.link_target);
+			ret = strscpy(orangefs_inode->link_target,
+			    new_op->downcall.resp.getattr.link_target,
+			    ORANGEFS_NAME_MAX);
+			if (ret == -E2BIG) {
+				ret = -EIO;
+				goto out_unlock;
+			}
+			inode->i_link = orangefs_inode->link_target;
+		}
+		break;
+	/* i.e. -1 */
+	default:
+		/* XXX: ESTALE?  This is what is done if it is not new. */
+		orangefs_make_bad_inode(inode);
+		ret = -ESTALE;
+		goto out_unlock;
+	}
+
+	inode->i_uid = make_kuid(&init_user_ns, new_op->
+	    downcall.resp.getattr.attributes.owner);
+	inode->i_gid = make_kgid(&init_user_ns, new_op->
+	    downcall.resp.getattr.attributes.group);
+	inode->i_atime.tv_sec = (time64_t)new_op->
+	    downcall.resp.getattr.attributes.atime;
+	inode->i_mtime.tv_sec = (time64_t)new_op->
+	    downcall.resp.getattr.attributes.mtime;
+	inode->i_ctime.tv_sec = (time64_t)new_op->
+	    downcall.resp.getattr.attributes.ctime;
+	inode->i_atime.tv_nsec = 0;
+	inode->i_mtime.tv_nsec = 0;
+	inode->i_ctime.tv_nsec = 0;
+
+	/* special case: mark the root inode as sticky */
+	inode->i_mode = type | (is_root_handle(inode) ? S_ISVTX : 0) |
+	    orangefs_inode_perms(&new_op->downcall.resp.getattr.attributes);
+
+	orangefs_inode->getattr_time = jiffies +
+	    orangefs_getattr_timeout_msecs*HZ/1000;
+	ret = 0;
+out_unlock:
+	spin_unlock(&inode->i_lock);
+out:
+	op_release(new_op);
+	return ret;
+}
+
+int orangefs_inode_check_changed(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	int ret;
+
+	gossip_debug(GOSSIP_UTILS_DEBUG, "%s: called on inode %pU\n", __func__,
+	    get_khandle_from_ino(inode));
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_GETATTR);
+	if (!new_op)
+		return -ENOMEM;
+	new_op->upcall.req.getattr.refn = orangefs_inode->refn;
+	new_op->upcall.req.getattr.mask = ORANGEFS_ATTR_SYS_TYPE |
+	    ORANGEFS_ATTR_SYS_LNK_TARGET;
+
+	ret = service_operation(new_op, __func__,
+	    get_interruptible_flag(inode));
+	if (ret != 0)
+		goto out;
+
+	ret = orangefs_inode_is_stale(inode,
+	    &new_op->downcall.resp.getattr.attributes,
+	    new_op->downcall.resp.getattr.link_target);
+out:
+	op_release(new_op);
+	return ret;
+}
+
+/*
+ * issues a orangefs setattr request to make sure the new attribute values
+ * take effect if successful.  returns 0 on success; -errno otherwise
+ */
+int orangefs_inode_setattr(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	int ret;
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_SETATTR);
+	if (!new_op)
+		return -ENOMEM;
+
+	spin_lock(&inode->i_lock);
+	new_op->upcall.uid = from_kuid(&init_user_ns, orangefs_inode->attr_uid);
+	new_op->upcall.gid = from_kgid(&init_user_ns, orangefs_inode->attr_gid);
+	new_op->upcall.req.setattr.refn = orangefs_inode->refn;
+	copy_attributes_from_inode(inode,
+	    &new_op->upcall.req.setattr.attributes);
+	orangefs_inode->attr_valid = 0;
+	if (!new_op->upcall.req.setattr.attributes.mask) {
+		spin_unlock(&inode->i_lock);
+		op_release(new_op);
+		return 0;
+	}
+	spin_unlock(&inode->i_lock);
+
+	ret = service_operation(new_op, __func__,
+	    get_interruptible_flag(inode) | ORANGEFS_OP_WRITEBACK);
+	gossip_debug(GOSSIP_UTILS_DEBUG,
+	    "orangefs_inode_setattr: returning %d\n", ret);
+	if (ret)
+		orangefs_make_bad_inode(inode);
+
+	op_release(new_op);
+
+	if (ret == 0)
+		orangefs_inode->getattr_time = jiffies - 1;
+	return ret;
+}
+
+/*
+ * The following is a very dirty hack that is now a permanent part of the
+ * ORANGEFS protocol. See protocol.h for more error definitions.
+ */
+
+/* The order matches include/orangefs-types.h in the OrangeFS source. */
+static int PINT_errno_mapping[] = {
+	0, EPERM, ENOENT, EINTR, EIO, ENXIO, EBADF, EAGAIN, ENOMEM,
+	EFAULT, EBUSY, EEXIST, ENODEV, ENOTDIR, EISDIR, EINVAL, EMFILE,
+	EFBIG, ENOSPC, EROFS, EMLINK, EPIPE, EDEADLK, ENAMETOOLONG,
+	ENOLCK, ENOSYS, ENOTEMPTY, ELOOP, EWOULDBLOCK, ENOMSG, EUNATCH,
+	EBADR, EDEADLOCK, ENODATA, ETIME, ENONET, EREMOTE, ECOMM,
+	EPROTO, EBADMSG, EOVERFLOW, ERESTART, EMSGSIZE, EPROTOTYPE,
+	ENOPROTOOPT, EPROTONOSUPPORT, EOPNOTSUPP, EADDRINUSE,
+	EADDRNOTAVAIL, ENETDOWN, ENETUNREACH, ENETRESET, ENOBUFS,
+	ETIMEDOUT, ECONNREFUSED, EHOSTDOWN, EHOSTUNREACH, EALREADY,
+	EACCES, ECONNRESET, ERANGE
+};
+
+int orangefs_normalize_to_errno(__s32 error_code)
+{
+	__u32 i;
+
+	/* Success */
+	if (error_code == 0) {
+		return 0;
+	/*
+	 * This shouldn't ever happen. If it does it should be fixed on the
+	 * server.
+	 */
+	} else if (error_code > 0) {
+		gossip_err("orangefs: error status received.\n");
+		gossip_err("orangefs: assuming error code is inverted.\n");
+		error_code = -error_code;
+	}
+
+	/*
+	 * XXX: This is very bad since error codes from ORANGEFS may not be
+	 * suitable for return into userspace.
+	 */
+
+	/*
+	 * Convert ORANGEFS error values into errno values suitable for return
+	 * from the kernel.
+	 */
+	if ((-error_code) & ORANGEFS_NON_ERRNO_ERROR_BIT) {
+		if (((-error_code) &
+		    (ORANGEFS_ERROR_NUMBER_BITS|ORANGEFS_NON_ERRNO_ERROR_BIT|
+		    ORANGEFS_ERROR_BIT)) == ORANGEFS_ECANCEL) {
+			/*
+			 * cancellation error codes generally correspond to
+			 * a timeout from the client's perspective
+			 */
+			error_code = -ETIMEDOUT;
+		} else {
+			/* assume a default error code */
+			gossip_err("%s: bad error code :%d:.\n",
+				__func__,
+				error_code);
+			error_code = -EINVAL;
+		}
+
+	/* Convert ORANGEFS encoded errno values into regular errno values. */
+	} else if ((-error_code) & ORANGEFS_ERROR_BIT) {
+		i = (-error_code) & ~(ORANGEFS_ERROR_BIT|ORANGEFS_ERROR_CLASS_BITS);
+		if (i < ARRAY_SIZE(PINT_errno_mapping))
+			error_code = -PINT_errno_mapping[i];
+		else
+			error_code = -EINVAL;
+
+	/*
+	 * Only ORANGEFS protocol error codes should ever come here. Otherwise
+	 * there is a bug somewhere.
+	 */
+	} else {
+		gossip_err("%s: unknown error code.\n", __func__);
+		error_code = -EINVAL;
+	}
+	return error_code;
+}
+
+#define NUM_MODES 11
+__s32 ORANGEFS_util_translate_mode(int mode)
+{
+	int ret = 0;
+	int i = 0;
+	static int modes[NUM_MODES] = {
+		S_IXOTH, S_IWOTH, S_IROTH,
+		S_IXGRP, S_IWGRP, S_IRGRP,
+		S_IXUSR, S_IWUSR, S_IRUSR,
+		S_ISGID, S_ISUID
+	};
+	static int orangefs_modes[NUM_MODES] = {
+		ORANGEFS_O_EXECUTE, ORANGEFS_O_WRITE, ORANGEFS_O_READ,
+		ORANGEFS_G_EXECUTE, ORANGEFS_G_WRITE, ORANGEFS_G_READ,
+		ORANGEFS_U_EXECUTE, ORANGEFS_U_WRITE, ORANGEFS_U_READ,
+		ORANGEFS_G_SGID, ORANGEFS_U_SUID
+	};
+
+	for (i = 0; i < NUM_MODES; i++)
+		if (mode & modes[i])
+			ret |= orangefs_modes[i];
+
+	return ret;
+}
+#undef NUM_MODES
diff --git a/fs/orangefs/protocol.h b/fs/orangefs/protocol.h
new file mode 100644
index 000000000..d403cf29a
--- /dev/null
+++ b/fs/orangefs/protocol.h
@@ -0,0 +1,362 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/spinlock_types.h>
+#include <linux/slab.h>
+#include <linux/ioctl.h>
+
+/* khandle stuff  ***********************************************************/
+
+/*
+ * The 2.9 core will put 64 bit handles in here like this:
+ *    1234 0000 0000 5678
+ * The 3.0 and beyond cores will put 128 bit handles in here like this:
+ *    1234 5678 90AB CDEF
+ * The kernel module will always use the first four bytes and
+ * the last four bytes as an inum.
+ */
+struct orangefs_khandle {
+	unsigned char u[16];
+}  __aligned(8);
+
+/*
+ * kernel version of an object ref.
+ */
+struct orangefs_object_kref {
+	struct orangefs_khandle khandle;
+	__s32 fs_id;
+	__s32 __pad1;
+};
+
+/*
+ * compare 2 khandles assumes little endian thus from large address to
+ * small address
+ */
+static inline int ORANGEFS_khandle_cmp(const struct orangefs_khandle *kh1,
+				   const struct orangefs_khandle *kh2)
+{
+	int i;
+
+	for (i = 15; i >= 0; i--) {
+		if (kh1->u[i] > kh2->u[i])
+			return 1;
+		if (kh1->u[i] < kh2->u[i])
+			return -1;
+	}
+
+	return 0;
+}
+
+static inline void ORANGEFS_khandle_to(const struct orangefs_khandle *kh,
+				   void *p, int size)
+{
+
+	memcpy(p, kh->u, 16);
+	memset(p + 16, 0, size - 16);
+
+}
+
+static inline void ORANGEFS_khandle_from(struct orangefs_khandle *kh,
+				     void *p, int size)
+{
+	memset(kh, 0, 16);
+	memcpy(kh->u, p, 16);
+
+}
+
+/* pvfs2-types.h ************************************************************/
+
+#define ORANGEFS_SUPER_MAGIC 0x20030528
+
+/*
+ * ORANGEFS error codes are a signed 32-bit integer. Error codes are negative, but
+ * the sign is stripped before decoding.
+ */
+
+/* Bit 31 is not used since it is the sign. */
+
+/*
+ * Bit 30 specifies that this is a ORANGEFS error. A ORANGEFS error is either an
+ * encoded errno value or a ORANGEFS protocol error.
+ */
+#define ORANGEFS_ERROR_BIT (1 << 30)
+
+/*
+ * Bit 29 specifies that this is a ORANGEFS protocol error and not an encoded
+ * errno value.
+ */
+#define ORANGEFS_NON_ERRNO_ERROR_BIT (1 << 29)
+
+/*
+ * Bits 9, 8, and 7 specify the error class, which encodes the section of
+ * server code the error originated in for logging purposes. It is not used
+ * in the kernel except to be masked out.
+ */
+#define ORANGEFS_ERROR_CLASS_BITS 0x380
+
+/* Bits 6 - 0 are reserved for the actual error code. */
+#define ORANGEFS_ERROR_NUMBER_BITS 0x7f
+
+/* Encoded errno values decoded by PINT_errno_mapping in orangefs-utils.c. */
+
+/* Our own ORANGEFS protocol error codes. */
+#define ORANGEFS_ECANCEL    (1|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_EDEVINIT   (2|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_EDETAIL    (3|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_EHOSTNTFD  (4|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_EADDRNTFD  (5|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_ENORECVR   (6|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_ETRYAGAIN  (7|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_ENOTPVFS   (8|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+#define ORANGEFS_ESECURITY  (9|ORANGEFS_NON_ERRNO_ERROR_BIT|ORANGEFS_ERROR_BIT)
+
+/* permission bits */
+#define ORANGEFS_O_EXECUTE (1 << 0)
+#define ORANGEFS_O_WRITE   (1 << 1)
+#define ORANGEFS_O_READ    (1 << 2)
+#define ORANGEFS_G_EXECUTE (1 << 3)
+#define ORANGEFS_G_WRITE   (1 << 4)
+#define ORANGEFS_G_READ    (1 << 5)
+#define ORANGEFS_U_EXECUTE (1 << 6)
+#define ORANGEFS_U_WRITE   (1 << 7)
+#define ORANGEFS_U_READ    (1 << 8)
+/* no ORANGEFS_U_VTX (sticky bit) */
+#define ORANGEFS_G_SGID    (1 << 10)
+#define ORANGEFS_U_SUID    (1 << 11)
+
+#define ORANGEFS_ITERATE_START    2147483646
+#define ORANGEFS_ITERATE_END      2147483645
+#define ORANGEFS_IMMUTABLE_FL FS_IMMUTABLE_FL
+#define ORANGEFS_APPEND_FL    FS_APPEND_FL
+#define ORANGEFS_NOATIME_FL   FS_NOATIME_FL
+#define ORANGEFS_MIRROR_FL    0x01000000ULL
+#define ORANGEFS_FS_ID_NULL       ((__s32)0)
+#define ORANGEFS_ATTR_SYS_UID                   (1 << 0)
+#define ORANGEFS_ATTR_SYS_GID                   (1 << 1)
+#define ORANGEFS_ATTR_SYS_PERM                  (1 << 2)
+#define ORANGEFS_ATTR_SYS_ATIME                 (1 << 3)
+#define ORANGEFS_ATTR_SYS_CTIME                 (1 << 4)
+#define ORANGEFS_ATTR_SYS_MTIME                 (1 << 5)
+#define ORANGEFS_ATTR_SYS_TYPE                  (1 << 6)
+#define ORANGEFS_ATTR_SYS_ATIME_SET             (1 << 7)
+#define ORANGEFS_ATTR_SYS_MTIME_SET             (1 << 8)
+#define ORANGEFS_ATTR_SYS_SIZE                  (1 << 20)
+#define ORANGEFS_ATTR_SYS_LNK_TARGET            (1 << 24)
+#define ORANGEFS_ATTR_SYS_DFILE_COUNT           (1 << 25)
+#define ORANGEFS_ATTR_SYS_DIRENT_COUNT          (1 << 26)
+#define ORANGEFS_ATTR_SYS_BLKSIZE               (1 << 28)
+#define ORANGEFS_ATTR_SYS_MIRROR_COPIES_COUNT   (1 << 29)
+#define ORANGEFS_ATTR_SYS_COMMON_ALL	\
+	(ORANGEFS_ATTR_SYS_UID	|	\
+	 ORANGEFS_ATTR_SYS_GID	|	\
+	 ORANGEFS_ATTR_SYS_PERM	|	\
+	 ORANGEFS_ATTR_SYS_ATIME	|	\
+	 ORANGEFS_ATTR_SYS_CTIME	|	\
+	 ORANGEFS_ATTR_SYS_MTIME	|	\
+	 ORANGEFS_ATTR_SYS_TYPE)
+
+#define ORANGEFS_ATTR_SYS_ALL_SETABLE		\
+(ORANGEFS_ATTR_SYS_COMMON_ALL-ORANGEFS_ATTR_SYS_TYPE)
+
+#define ORANGEFS_ATTR_SYS_ALL_NOHINT			\
+	(ORANGEFS_ATTR_SYS_COMMON_ALL		|	\
+	 ORANGEFS_ATTR_SYS_SIZE			|	\
+	 ORANGEFS_ATTR_SYS_LNK_TARGET		|	\
+	 ORANGEFS_ATTR_SYS_DFILE_COUNT		|	\
+	 ORANGEFS_ATTR_SYS_MIRROR_COPIES_COUNT	|	\
+	 ORANGEFS_ATTR_SYS_DIRENT_COUNT		|	\
+	 ORANGEFS_ATTR_SYS_BLKSIZE)
+
+#define ORANGEFS_XATTR_REPLACE 0x2
+#define ORANGEFS_XATTR_CREATE  0x1
+#define ORANGEFS_MAX_SERVER_ADDR_LEN 256
+#define ORANGEFS_NAME_MAX                256
+/*
+ * max extended attribute name len as imposed by the VFS and exploited for the
+ * upcall request types.
+ * NOTE: Please retain them as multiples of 8 even if you wish to change them
+ * This is *NECESSARY* for supporting 32 bit user-space binaries on a 64-bit
+ * kernel. Due to implementation within DBPF, this really needs to be
+ * ORANGEFS_NAME_MAX, which it was the same value as, but no reason to let it
+ * break if that changes in the future.
+ */
+#define ORANGEFS_MAX_XATTR_NAMELEN   ORANGEFS_NAME_MAX	/* Not the same as
+						 * XATTR_NAME_MAX defined
+						 * by <linux/xattr.h>
+						 */
+#define ORANGEFS_MAX_XATTR_VALUELEN  8192	/* Not the same as XATTR_SIZE_MAX
+					 * defined by <linux/xattr.h>
+					 */
+#define ORANGEFS_MAX_XATTR_LISTLEN   16	/* Not the same as XATTR_LIST_MAX
+					 * defined by <linux/xattr.h>
+					 */
+/*
+ * ORANGEFS I/O operation types, used in both system and server interfaces.
+ */
+enum ORANGEFS_io_type {
+	ORANGEFS_IO_READ = 1,
+	ORANGEFS_IO_WRITE = 2
+};
+
+/*
+ * If this enum is modified the server parameters related to the precreate pool
+ * batch and low threshold sizes may need to be modified  to reflect this
+ * change.
+ */
+enum orangefs_ds_type {
+	ORANGEFS_TYPE_NONE = 0,
+	ORANGEFS_TYPE_METAFILE = (1 << 0),
+	ORANGEFS_TYPE_DATAFILE = (1 << 1),
+	ORANGEFS_TYPE_DIRECTORY = (1 << 2),
+	ORANGEFS_TYPE_SYMLINK = (1 << 3),
+	ORANGEFS_TYPE_DIRDATA = (1 << 4),
+	ORANGEFS_TYPE_INTERNAL = (1 << 5)	/* for the server's private use */
+};
+
+/* This structure is used by the VFS-client interaction alone */
+struct ORANGEFS_keyval_pair {
+	char key[ORANGEFS_MAX_XATTR_NAMELEN];
+	__s32 key_sz;	/* __s32 for portable, fixed-size structures */
+	__s32 val_sz;
+	char val[ORANGEFS_MAX_XATTR_VALUELEN];
+};
+
+/* pvfs2-sysint.h ***********************************************************/
+/* Describes attributes for a file, directory, or symlink. */
+struct ORANGEFS_sys_attr_s {
+	__u32 owner;
+	__u32 group;
+	__u32 perms;
+	__u64 atime;
+	__u64 mtime;
+	__u64 ctime;
+	__s64 size;
+
+	/* NOTE: caller must free if valid */
+	char *link_target;
+
+	/* Changed to __s32 so that size of structure does not change */
+	__s32 dfile_count;
+
+	/* Changed to __s32 so that size of structure does not change */
+	__s32 distr_dir_servers_initial;
+
+	/* Changed to __s32 so that size of structure does not change */
+	__s32 distr_dir_servers_max;
+
+	/* Changed to __s32 so that size of structure does not change */
+	__s32 distr_dir_split_size;
+
+	__u32 mirror_copies_count;
+
+	/* NOTE: caller must free if valid */
+	char *dist_name;
+
+	/* NOTE: caller must free if valid */
+	char *dist_params;
+
+	__s64 dirent_count;
+	enum orangefs_ds_type objtype;
+	__u64 flags;
+	__u32 mask;
+	__s64 blksize;
+};
+
+#define ORANGEFS_LOOKUP_LINK_NO_FOLLOW 0
+
+/* pint-dev.h ***************************************************************/
+
+/* parameter structure used in ORANGEFS_DEV_DEBUG ioctl command */
+struct dev_mask_info_s {
+	enum {
+		KERNEL_MASK,
+		CLIENT_MASK,
+	} mask_type;
+	__u64 mask_value;
+};
+
+struct dev_mask2_info_s {
+	__u64 mask1_value;
+	__u64 mask2_value;
+};
+
+/* pvfs2-util.h *************************************************************/
+__s32 ORANGEFS_util_translate_mode(int mode);
+
+/* pvfs2-debug.h ************************************************************/
+#include "orangefs-debug.h"
+
+/* pvfs2-internal.h *********************************************************/
+#define llu(x) (unsigned long long)(x)
+#define lld(x) (long long)(x)
+
+/* pint-dev-shared.h ********************************************************/
+#define ORANGEFS_DEV_MAGIC 'k'
+
+#define ORANGEFS_READDIR_DEFAULT_DESC_COUNT  5
+
+#define DEV_GET_MAGIC           0x1
+#define DEV_GET_MAX_UPSIZE      0x2
+#define DEV_GET_MAX_DOWNSIZE    0x3
+#define DEV_MAP                 0x4
+#define DEV_REMOUNT_ALL         0x5
+#define DEV_DEBUG               0x6
+#define DEV_UPSTREAM            0x7
+#define DEV_CLIENT_MASK         0x8
+#define DEV_CLIENT_STRING       0x9
+#define DEV_MAX_NR              0xa
+
+/* supported ioctls, codes are with respect to user-space */
+enum {
+	ORANGEFS_DEV_GET_MAGIC = _IOW(ORANGEFS_DEV_MAGIC, DEV_GET_MAGIC, __s32),
+	ORANGEFS_DEV_GET_MAX_UPSIZE =
+	    _IOW(ORANGEFS_DEV_MAGIC, DEV_GET_MAX_UPSIZE, __s32),
+	ORANGEFS_DEV_GET_MAX_DOWNSIZE =
+	    _IOW(ORANGEFS_DEV_MAGIC, DEV_GET_MAX_DOWNSIZE, __s32),
+	ORANGEFS_DEV_MAP = _IO(ORANGEFS_DEV_MAGIC, DEV_MAP),
+	ORANGEFS_DEV_REMOUNT_ALL = _IO(ORANGEFS_DEV_MAGIC, DEV_REMOUNT_ALL),
+	ORANGEFS_DEV_DEBUG = _IOR(ORANGEFS_DEV_MAGIC, DEV_DEBUG, __s32),
+	ORANGEFS_DEV_UPSTREAM = _IOW(ORANGEFS_DEV_MAGIC, DEV_UPSTREAM, int),
+	ORANGEFS_DEV_CLIENT_MASK = _IOW(ORANGEFS_DEV_MAGIC,
+				    DEV_CLIENT_MASK,
+				    struct dev_mask2_info_s),
+	ORANGEFS_DEV_CLIENT_STRING = _IOW(ORANGEFS_DEV_MAGIC,
+				      DEV_CLIENT_STRING,
+				      char *),
+	ORANGEFS_DEV_MAXNR = DEV_MAX_NR,
+};
+
+/*
+ * version number for use in communicating between kernel space and user
+ * space. Zero signifies the upstream version of the kernel module.
+ */
+#define ORANGEFS_KERNEL_PROTO_VERSION 0
+#define ORANGEFS_MINIMUM_USERSPACE_VERSION 20903
+
+/*
+ * describes memory regions to map in the ORANGEFS_DEV_MAP ioctl.
+ * NOTE: See devorangefs-req.c for 32 bit compat structure.
+ * Since this structure has a variable-sized layout that is different
+ * on 32 and 64 bit platforms, we need to normalize to a 64 bit layout
+ * on such systems before servicing ioctl calls from user-space binaries
+ * that may be 32 bit!
+ */
+struct ORANGEFS_dev_map_desc {
+	void __user *ptr;
+	__s32 total_size;
+	__s32 size;
+	__s32 count;
+};
+
+/* gossip.h *****************************************************************/
+
+extern __u64 orangefs_gossip_debug_mask;
+
+/* try to avoid function call overhead by checking masks in macro */
+#define gossip_debug(mask, fmt, ...)					\
+do {									\
+	if (orangefs_gossip_debug_mask & (mask))			\
+		printk(KERN_DEBUG fmt, ##__VA_ARGS__);			\
+} while (0)
+
+#define gossip_err pr_err
diff --git a/fs/orangefs/super.c b/fs/orangefs/super.c
new file mode 100644
index 000000000..5254256a2
--- /dev/null
+++ b/fs/orangefs/super.c
@@ -0,0 +1,665 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+#include <linux/parser.h>
+#include <linux/hashtable.h>
+#include <linux/seq_file.h>
+
+/* a cache for orangefs-inode objects (i.e. orangefs inode private data) */
+static struct kmem_cache *orangefs_inode_cache;
+
+/* list for storing orangefs specific superblocks in use */
+LIST_HEAD(orangefs_superblocks);
+
+DEFINE_SPINLOCK(orangefs_superblocks_lock);
+
+enum {
+	Opt_intr,
+	Opt_acl,
+	Opt_local_lock,
+
+	Opt_err
+};
+
+static const match_table_t tokens = {
+	{ Opt_acl,		"acl" },
+	{ Opt_intr,		"intr" },
+	{ Opt_local_lock,	"local_lock" },
+	{ Opt_err,	NULL }
+};
+
+uint64_t orangefs_features;
+
+static int orangefs_show_options(struct seq_file *m, struct dentry *root)
+{
+	struct orangefs_sb_info_s *orangefs_sb = ORANGEFS_SB(root->d_sb);
+
+	if (root->d_sb->s_flags & SB_POSIXACL)
+		seq_puts(m, ",acl");
+	if (orangefs_sb->flags & ORANGEFS_OPT_INTR)
+		seq_puts(m, ",intr");
+	if (orangefs_sb->flags & ORANGEFS_OPT_LOCAL_LOCK)
+		seq_puts(m, ",local_lock");
+	return 0;
+}
+
+static int parse_mount_options(struct super_block *sb, char *options,
+		int silent)
+{
+	struct orangefs_sb_info_s *orangefs_sb = ORANGEFS_SB(sb);
+	substring_t args[MAX_OPT_ARGS];
+	char *p;
+
+	/*
+	 * Force any potential flags that might be set from the mount
+	 * to zero, ie, initialize to unset.
+	 */
+	sb->s_flags &= ~SB_POSIXACL;
+	orangefs_sb->flags &= ~ORANGEFS_OPT_INTR;
+	orangefs_sb->flags &= ~ORANGEFS_OPT_LOCAL_LOCK;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case Opt_acl:
+			sb->s_flags |= SB_POSIXACL;
+			break;
+		case Opt_intr:
+			orangefs_sb->flags |= ORANGEFS_OPT_INTR;
+			break;
+		case Opt_local_lock:
+			orangefs_sb->flags |= ORANGEFS_OPT_LOCAL_LOCK;
+			break;
+		default:
+			goto fail;
+		}
+	}
+
+	return 0;
+fail:
+	if (!silent)
+		gossip_err("Error: mount option [%s] is not supported.\n", p);
+	return -EINVAL;
+}
+
+static void orangefs_inode_cache_ctor(void *req)
+{
+	struct orangefs_inode_s *orangefs_inode = req;
+
+	inode_init_once(&orangefs_inode->vfs_inode);
+	init_rwsem(&orangefs_inode->xattr_sem);
+}
+
+static struct inode *orangefs_alloc_inode(struct super_block *sb)
+{
+	struct orangefs_inode_s *orangefs_inode;
+
+	orangefs_inode = alloc_inode_sb(sb, orangefs_inode_cache, GFP_KERNEL);
+	if (!orangefs_inode)
+		return NULL;
+
+	/*
+	 * We want to clear everything except for rw_semaphore and the
+	 * vfs_inode.
+	 */
+	memset(&orangefs_inode->refn.khandle, 0, 16);
+	orangefs_inode->refn.fs_id = ORANGEFS_FS_ID_NULL;
+	orangefs_inode->last_failed_block_index_read = 0;
+	memset(orangefs_inode->link_target, 0, sizeof(orangefs_inode->link_target));
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "orangefs_alloc_inode: allocated %p\n",
+		     &orangefs_inode->vfs_inode);
+	return &orangefs_inode->vfs_inode;
+}
+
+static void orangefs_free_inode(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_cached_xattr *cx;
+	struct hlist_node *tmp;
+	int i;
+
+	hash_for_each_safe(orangefs_inode->xattr_cache, i, tmp, cx, node) {
+		hlist_del(&cx->node);
+		kfree(cx);
+	}
+
+	kmem_cache_free(orangefs_inode_cache, orangefs_inode);
+}
+
+static void orangefs_destroy_inode(struct inode *inode)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+			"%s: deallocated %p destroying inode %pU\n",
+			__func__, orangefs_inode, get_khandle_from_ino(inode));
+}
+
+static int orangefs_write_inode(struct inode *inode,
+				struct writeback_control *wbc)
+{
+	gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_write_inode\n");
+	return orangefs_inode_setattr(inode);
+}
+
+/*
+ * NOTE: information filled in here is typically reflected in the
+ * output of the system command 'df'
+*/
+static int orangefs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	int ret = -ENOMEM;
+	struct orangefs_kernel_op_s *new_op = NULL;
+	int flags = 0;
+	struct super_block *sb = NULL;
+
+	sb = dentry->d_sb;
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+			"%s: called on sb %p (fs_id is %d)\n",
+			__func__,
+			sb,
+			(int)(ORANGEFS_SB(sb)->fs_id));
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_STATFS);
+	if (!new_op)
+		return ret;
+	new_op->upcall.req.statfs.fs_id = ORANGEFS_SB(sb)->fs_id;
+
+	if (ORANGEFS_SB(sb)->flags & ORANGEFS_OPT_INTR)
+		flags = ORANGEFS_OP_INTERRUPTIBLE;
+
+	ret = service_operation(new_op, "orangefs_statfs", flags);
+
+	if (new_op->downcall.status < 0)
+		goto out_op_release;
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "%s: got %ld blocks available | "
+		     "%ld blocks total | %ld block size | "
+		     "%ld files total | %ld files avail\n",
+		     __func__,
+		     (long)new_op->downcall.resp.statfs.blocks_avail,
+		     (long)new_op->downcall.resp.statfs.blocks_total,
+		     (long)new_op->downcall.resp.statfs.block_size,
+		     (long)new_op->downcall.resp.statfs.files_total,
+		     (long)new_op->downcall.resp.statfs.files_avail);
+
+	buf->f_type = sb->s_magic;
+	memcpy(&buf->f_fsid, &ORANGEFS_SB(sb)->fs_id, sizeof(buf->f_fsid));
+	buf->f_bsize = new_op->downcall.resp.statfs.block_size;
+	buf->f_namelen = ORANGEFS_NAME_MAX;
+
+	buf->f_blocks = (sector_t) new_op->downcall.resp.statfs.blocks_total;
+	buf->f_bfree = (sector_t) new_op->downcall.resp.statfs.blocks_avail;
+	buf->f_bavail = (sector_t) new_op->downcall.resp.statfs.blocks_avail;
+	buf->f_files = (sector_t) new_op->downcall.resp.statfs.files_total;
+	buf->f_ffree = (sector_t) new_op->downcall.resp.statfs.files_avail;
+	buf->f_frsize = 0;
+
+out_op_release:
+	op_release(new_op);
+	gossip_debug(GOSSIP_SUPER_DEBUG, "%s: returning %d\n", __func__, ret);
+	return ret;
+}
+
+/*
+ * Remount as initiated by VFS layer.  We just need to reparse the mount
+ * options, no need to signal pvfs2-client-core about it.
+ */
+static int orangefs_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+	gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_remount_fs: called\n");
+	return parse_mount_options(sb, data, 1);
+}
+
+/*
+ * Remount as initiated by pvfs2-client-core on restart.  This is used to
+ * repopulate mount information left from previous pvfs2-client-core.
+ *
+ * the idea here is that given a valid superblock, we're
+ * re-initializing the user space client with the initial mount
+ * information specified when the super block was first initialized.
+ * this is very different than the first initialization/creation of a
+ * superblock.  we use the special service_priority_operation to make
+ * sure that the mount gets ahead of any other pending operation that
+ * is waiting for servicing.  this means that the pvfs2-client won't
+ * fail to start several times for all other pending operations before
+ * the client regains all of the mount information from us.
+ * NOTE: this function assumes that the request_mutex is already acquired!
+ */
+int orangefs_remount(struct orangefs_sb_info_s *orangefs_sb)
+{
+	struct orangefs_kernel_op_s *new_op;
+	int ret = -EINVAL;
+
+	gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_remount: called\n");
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_FS_MOUNT);
+	if (!new_op)
+		return -ENOMEM;
+	strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
+		orangefs_sb->devname,
+		ORANGEFS_MAX_SERVER_ADDR_LEN);
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "Attempting ORANGEFS Remount via host %s\n",
+		     new_op->upcall.req.fs_mount.orangefs_config_server);
+
+	/*
+	 * we assume that the calling function has already acquired the
+	 * request_mutex to prevent other operations from bypassing
+	 * this one
+	 */
+	ret = service_operation(new_op, "orangefs_remount",
+		ORANGEFS_OP_PRIORITY | ORANGEFS_OP_NO_MUTEX);
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "orangefs_remount: mount got return value of %d\n",
+		     ret);
+	if (ret == 0) {
+		/*
+		 * store the id assigned to this sb -- it's just a
+		 * short-lived mapping that the system interface uses
+		 * to map this superblock to a particular mount entry
+		 */
+		orangefs_sb->id = new_op->downcall.resp.fs_mount.id;
+		orangefs_sb->mount_pending = 0;
+	}
+
+	op_release(new_op);
+
+	if (orangefs_userspace_version >= 20906) {
+		new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES);
+		if (!new_op)
+			return -ENOMEM;
+		new_op->upcall.req.features.features = 0;
+		ret = service_operation(new_op, "orangefs_features",
+		    ORANGEFS_OP_PRIORITY | ORANGEFS_OP_NO_MUTEX);
+		if (!ret)
+			orangefs_features =
+			    new_op->downcall.resp.features.features;
+		else
+			orangefs_features = 0;
+		op_release(new_op);
+	} else {
+		orangefs_features = 0;
+	}
+
+	return ret;
+}
+
+int fsid_key_table_initialize(void)
+{
+	return 0;
+}
+
+void fsid_key_table_finalize(void)
+{
+}
+
+static const struct super_operations orangefs_s_ops = {
+	.alloc_inode = orangefs_alloc_inode,
+	.free_inode = orangefs_free_inode,
+	.destroy_inode = orangefs_destroy_inode,
+	.write_inode = orangefs_write_inode,
+	.drop_inode = generic_delete_inode,
+	.statfs = orangefs_statfs,
+	.remount_fs = orangefs_remount_fs,
+	.show_options = orangefs_show_options,
+};
+
+static struct dentry *orangefs_fh_to_dentry(struct super_block *sb,
+				  struct fid *fid,
+				  int fh_len,
+				  int fh_type)
+{
+	struct orangefs_object_kref refn;
+
+	if (fh_len < 5 || fh_type > 2)
+		return NULL;
+
+	ORANGEFS_khandle_from(&(refn.khandle), fid->raw, 16);
+	refn.fs_id = (u32) fid->raw[4];
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "fh_to_dentry: handle %pU, fs_id %d\n",
+		     &refn.khandle,
+		     refn.fs_id);
+
+	return d_obtain_alias(orangefs_iget(sb, &refn));
+}
+
+static int orangefs_encode_fh(struct inode *inode,
+		    __u32 *fh,
+		    int *max_len,
+		    struct inode *parent)
+{
+	int len = parent ? 10 : 5;
+	int type = 1;
+	struct orangefs_object_kref refn;
+
+	if (*max_len < len) {
+		gossip_err("fh buffer is too small for encoding\n");
+		*max_len = len;
+		type = 255;
+		goto out;
+	}
+
+	refn = ORANGEFS_I(inode)->refn;
+	ORANGEFS_khandle_to(&refn.khandle, fh, 16);
+	fh[4] = refn.fs_id;
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "Encoding fh: handle %pU, fsid %u\n",
+		     &refn.khandle,
+		     refn.fs_id);
+
+
+	if (parent) {
+		refn = ORANGEFS_I(parent)->refn;
+		ORANGEFS_khandle_to(&refn.khandle, (char *) fh + 20, 16);
+		fh[9] = refn.fs_id;
+
+		type = 2;
+		gossip_debug(GOSSIP_SUPER_DEBUG,
+			     "Encoding parent: handle %pU, fsid %u\n",
+			     &refn.khandle,
+			     refn.fs_id);
+	}
+	*max_len = len;
+
+out:
+	return type;
+}
+
+static const struct export_operations orangefs_export_ops = {
+	.encode_fh = orangefs_encode_fh,
+	.fh_to_dentry = orangefs_fh_to_dentry,
+};
+
+static int orangefs_unmount(int id, __s32 fs_id, const char *devname)
+{
+	struct orangefs_kernel_op_s *op;
+	int r;
+	op = op_alloc(ORANGEFS_VFS_OP_FS_UMOUNT);
+	if (!op)
+		return -ENOMEM;
+	op->upcall.req.fs_umount.id = id;
+	op->upcall.req.fs_umount.fs_id = fs_id;
+	strncpy(op->upcall.req.fs_umount.orangefs_config_server,
+	    devname, ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+	r = service_operation(op, "orangefs_fs_umount", 0);
+	/* Not much to do about an error here. */
+	if (r)
+		gossip_err("orangefs_unmount: service_operation %d\n", r);
+	op_release(op);
+	return r;
+}
+
+static int orangefs_fill_sb(struct super_block *sb,
+		struct orangefs_fs_mount_response *fs_mount,
+		void *data, int silent)
+{
+	int ret;
+	struct inode *root;
+	struct dentry *root_dentry;
+	struct orangefs_object_kref root_object;
+
+	ORANGEFS_SB(sb)->sb = sb;
+
+	ORANGEFS_SB(sb)->root_khandle = fs_mount->root_khandle;
+	ORANGEFS_SB(sb)->fs_id = fs_mount->fs_id;
+	ORANGEFS_SB(sb)->id = fs_mount->id;
+
+	if (data) {
+		ret = parse_mount_options(sb, data, silent);
+		if (ret)
+			return ret;
+	}
+
+	/* Hang the xattr handlers off the superblock */
+	sb->s_xattr = orangefs_xattr_handlers;
+	sb->s_magic = ORANGEFS_SUPER_MAGIC;
+	sb->s_op = &orangefs_s_ops;
+	sb->s_d_op = &orangefs_dentry_operations;
+
+	sb->s_blocksize = PAGE_SIZE;
+	sb->s_blocksize_bits = PAGE_SHIFT;
+	sb->s_maxbytes = MAX_LFS_FILESIZE;
+
+	ret = super_setup_bdi(sb);
+	if (ret)
+		return ret;
+
+	root_object.khandle = ORANGEFS_SB(sb)->root_khandle;
+	root_object.fs_id = ORANGEFS_SB(sb)->fs_id;
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "get inode %pU, fsid %d\n",
+		     &root_object.khandle,
+		     root_object.fs_id);
+
+	root = orangefs_iget(sb, &root_object);
+	if (IS_ERR(root))
+		return PTR_ERR(root);
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "Allocated root inode [%p] with mode %x\n",
+		     root,
+		     root->i_mode);
+
+	/* allocates and places root dentry in dcache */
+	root_dentry = d_make_root(root);
+	if (!root_dentry)
+		return -ENOMEM;
+
+	sb->s_export_op = &orangefs_export_ops;
+	sb->s_root = root_dentry;
+	return 0;
+}
+
+struct dentry *orangefs_mount(struct file_system_type *fst,
+			   int flags,
+			   const char *devname,
+			   void *data)
+{
+	int ret;
+	struct super_block *sb = ERR_PTR(-EINVAL);
+	struct orangefs_kernel_op_s *new_op;
+	struct dentry *d = ERR_PTR(-EINVAL);
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "orangefs_mount: called with devname %s\n",
+		     devname);
+
+	if (!devname) {
+		gossip_err("ERROR: device name not specified.\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_FS_MOUNT);
+	if (!new_op)
+		return ERR_PTR(-ENOMEM);
+
+	strncpy(new_op->upcall.req.fs_mount.orangefs_config_server,
+		devname,
+		ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "Attempting ORANGEFS Mount via host %s\n",
+		     new_op->upcall.req.fs_mount.orangefs_config_server);
+
+	ret = service_operation(new_op, "orangefs_mount", 0);
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "orangefs_mount: mount got return value of %d\n", ret);
+	if (ret)
+		goto free_op;
+
+	if (new_op->downcall.resp.fs_mount.fs_id == ORANGEFS_FS_ID_NULL) {
+		gossip_err("ERROR: Retrieved null fs_id\n");
+		ret = -EINVAL;
+		goto free_op;
+	}
+
+	sb = sget(fst, NULL, set_anon_super, flags, NULL);
+
+	if (IS_ERR(sb)) {
+		d = ERR_CAST(sb);
+		orangefs_unmount(new_op->downcall.resp.fs_mount.id,
+		    new_op->downcall.resp.fs_mount.fs_id, devname);
+		goto free_op;
+	}
+
+	/* alloc and init our private orangefs sb info */
+	sb->s_fs_info = kzalloc(sizeof(struct orangefs_sb_info_s), GFP_KERNEL);
+	if (!ORANGEFS_SB(sb)) {
+		d = ERR_PTR(-ENOMEM);
+		goto free_sb_and_op;
+	}
+
+	ret = orangefs_fill_sb(sb,
+	      &new_op->downcall.resp.fs_mount, data,
+	      flags & SB_SILENT ? 1 : 0);
+
+	if (ret) {
+		d = ERR_PTR(ret);
+		goto free_sb_and_op;
+	}
+
+	/*
+	 * on successful mount, store the devname and data
+	 * used
+	 */
+	strncpy(ORANGEFS_SB(sb)->devname,
+		devname,
+		ORANGEFS_MAX_SERVER_ADDR_LEN - 1);
+
+	/* mount_pending must be cleared */
+	ORANGEFS_SB(sb)->mount_pending = 0;
+
+	/*
+	 * finally, add this sb to our list of known orangefs
+	 * sb's
+	 */
+	gossip_debug(GOSSIP_SUPER_DEBUG,
+		     "Adding SB %p to orangefs superblocks\n",
+		     ORANGEFS_SB(sb));
+	spin_lock(&orangefs_superblocks_lock);
+	list_add_tail(&ORANGEFS_SB(sb)->list, &orangefs_superblocks);
+	spin_unlock(&orangefs_superblocks_lock);
+	op_release(new_op);
+
+	/* Must be removed from the list now. */
+	ORANGEFS_SB(sb)->no_list = 0;
+
+	if (orangefs_userspace_version >= 20906) {
+		new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES);
+		if (!new_op)
+			return ERR_PTR(-ENOMEM);
+		new_op->upcall.req.features.features = 0;
+		ret = service_operation(new_op, "orangefs_features", 0);
+		orangefs_features = new_op->downcall.resp.features.features;
+		op_release(new_op);
+	} else {
+		orangefs_features = 0;
+	}
+
+	return dget(sb->s_root);
+
+free_sb_and_op:
+	/* Will call orangefs_kill_sb with sb not in list. */
+	ORANGEFS_SB(sb)->no_list = 1;
+	/* ORANGEFS_VFS_OP_FS_UMOUNT is done by orangefs_kill_sb. */
+	deactivate_locked_super(sb);
+free_op:
+	gossip_err("orangefs_mount: mount request failed with %d\n", ret);
+	if (ret == -EINVAL) {
+		gossip_err("Ensure that all orangefs-servers have the same FS configuration files\n");
+		gossip_err("Look at pvfs2-client-core log file (typically /tmp/pvfs2-client.log) for more details\n");
+	}
+
+	op_release(new_op);
+
+	return d;
+}
+
+void orangefs_kill_sb(struct super_block *sb)
+{
+	int r;
+	gossip_debug(GOSSIP_SUPER_DEBUG, "orangefs_kill_sb: called\n");
+
+	/* provided sb cleanup */
+	kill_anon_super(sb);
+
+	if (!ORANGEFS_SB(sb)) {
+		mutex_lock(&orangefs_request_mutex);
+		mutex_unlock(&orangefs_request_mutex);
+		return;
+	}
+	/*
+	 * issue the unmount to userspace to tell it to remove the
+	 * dynamic mount info it has for this superblock
+	 */
+	r = orangefs_unmount(ORANGEFS_SB(sb)->id, ORANGEFS_SB(sb)->fs_id,
+	    ORANGEFS_SB(sb)->devname);
+	if (!r)
+		ORANGEFS_SB(sb)->mount_pending = 1;
+
+	if (!ORANGEFS_SB(sb)->no_list) {
+		/* remove the sb from our list of orangefs specific sb's */
+		spin_lock(&orangefs_superblocks_lock);
+		/* not list_del_init */
+		__list_del_entry(&ORANGEFS_SB(sb)->list);
+		ORANGEFS_SB(sb)->list.prev = NULL;
+		spin_unlock(&orangefs_superblocks_lock);
+	}
+
+	/*
+	 * make sure that ORANGEFS_DEV_REMOUNT_ALL loop that might've seen us
+	 * gets completed before we free the dang thing.
+	 */
+	mutex_lock(&orangefs_request_mutex);
+	mutex_unlock(&orangefs_request_mutex);
+
+	/* free the orangefs superblock private data */
+	kfree(ORANGEFS_SB(sb));
+}
+
+int orangefs_inode_cache_initialize(void)
+{
+	orangefs_inode_cache = kmem_cache_create_usercopy(
+					"orangefs_inode_cache",
+					sizeof(struct orangefs_inode_s),
+					0,
+					ORANGEFS_CACHE_CREATE_FLAGS,
+					offsetof(struct orangefs_inode_s,
+						link_target),
+					sizeof_field(struct orangefs_inode_s,
+						link_target),
+					orangefs_inode_cache_ctor);
+
+	if (!orangefs_inode_cache) {
+		gossip_err("Cannot create orangefs_inode_cache\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+int orangefs_inode_cache_finalize(void)
+{
+	kmem_cache_destroy(orangefs_inode_cache);
+	return 0;
+}
diff --git a/fs/orangefs/symlink.c b/fs/orangefs/symlink.c
new file mode 100644
index 000000000..db107fe91
--- /dev/null
+++ b/fs/orangefs/symlink.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+const struct inode_operations orangefs_symlink_inode_operations = {
+	.get_link = simple_get_link,
+	.setattr = orangefs_setattr,
+	.getattr = orangefs_getattr,
+	.listxattr = orangefs_listxattr,
+	.permission = orangefs_permission,
+	.update_time = orangefs_update_time,
+};
diff --git a/fs/orangefs/upcall.h b/fs/orangefs/upcall.h
new file mode 100644
index 000000000..16118452a
--- /dev/null
+++ b/fs/orangefs/upcall.h
@@ -0,0 +1,260 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ *
+ * See COPYING in top-level directory.
+ */
+
+#ifndef __UPCALL_H
+#define __UPCALL_H
+
+/*
+ * Sanitized this header file to fix
+ * 32-64 bit interaction issues between
+ * client-core and device
+ */
+struct orangefs_io_request_s {
+	__s32 __pad1;
+	__s32 buf_index;
+	__s32 count;
+	__s32 __pad2;
+	__s64 offset;
+	struct orangefs_object_kref refn;
+	enum ORANGEFS_io_type io_type;
+	__s32 readahead_size;
+};
+
+struct orangefs_lookup_request_s {
+	__s32 sym_follow;
+	__s32 __pad1;
+	struct orangefs_object_kref parent_refn;
+	char d_name[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_create_request_s {
+	struct orangefs_object_kref parent_refn;
+	struct ORANGEFS_sys_attr_s attributes;
+	char d_name[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_symlink_request_s {
+	struct orangefs_object_kref parent_refn;
+	struct ORANGEFS_sys_attr_s attributes;
+	char entry_name[ORANGEFS_NAME_MAX];
+	char target[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_getattr_request_s {
+	struct orangefs_object_kref refn;
+	__u32 mask;
+	__u32 __pad1;
+};
+
+struct orangefs_setattr_request_s {
+	struct orangefs_object_kref refn;
+	struct ORANGEFS_sys_attr_s attributes;
+};
+
+struct orangefs_remove_request_s {
+	struct orangefs_object_kref parent_refn;
+	char d_name[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_mkdir_request_s {
+	struct orangefs_object_kref parent_refn;
+	struct ORANGEFS_sys_attr_s attributes;
+	char d_name[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_readdir_request_s {
+	struct orangefs_object_kref refn;
+	__u64 token;
+	__s32 max_dirent_count;
+	__s32 buf_index;
+};
+
+struct orangefs_readdirplus_request_s {
+	struct orangefs_object_kref refn;
+	__u64 token;
+	__s32 max_dirent_count;
+	__u32 mask;
+	__s32 buf_index;
+	__s32 __pad1;
+};
+
+struct orangefs_rename_request_s {
+	struct orangefs_object_kref old_parent_refn;
+	struct orangefs_object_kref new_parent_refn;
+	char d_old_name[ORANGEFS_NAME_MAX];
+	char d_new_name[ORANGEFS_NAME_MAX];
+};
+
+struct orangefs_statfs_request_s {
+	__s32 fs_id;
+	__s32 __pad1;
+};
+
+struct orangefs_truncate_request_s {
+	struct orangefs_object_kref refn;
+	__s64 size;
+};
+
+struct orangefs_ra_cache_flush_request_s {
+	struct orangefs_object_kref refn;
+};
+
+struct orangefs_fs_mount_request_s {
+	char orangefs_config_server[ORANGEFS_MAX_SERVER_ADDR_LEN];
+};
+
+struct orangefs_fs_umount_request_s {
+	__s32 id;
+	__s32 fs_id;
+	char orangefs_config_server[ORANGEFS_MAX_SERVER_ADDR_LEN];
+};
+
+struct orangefs_getxattr_request_s {
+	struct orangefs_object_kref refn;
+	__s32 key_sz;
+	__s32 __pad1;
+	char key[ORANGEFS_MAX_XATTR_NAMELEN];
+};
+
+struct orangefs_setxattr_request_s {
+	struct orangefs_object_kref refn;
+	struct ORANGEFS_keyval_pair keyval;
+	__s32 flags;
+	__s32 __pad1;
+};
+
+struct orangefs_listxattr_request_s {
+	struct orangefs_object_kref refn;
+	__s32 requested_count;
+	__s32 __pad1;
+	__u64 token;
+};
+
+struct orangefs_removexattr_request_s {
+	struct orangefs_object_kref refn;
+	__s32 key_sz;
+	__s32 __pad1;
+	char key[ORANGEFS_MAX_XATTR_NAMELEN];
+};
+
+struct orangefs_op_cancel_s {
+	__u64 op_tag;
+};
+
+struct orangefs_fsync_request_s {
+	struct orangefs_object_kref refn;
+};
+
+enum orangefs_param_request_type {
+	ORANGEFS_PARAM_REQUEST_SET = 1,
+	ORANGEFS_PARAM_REQUEST_GET = 2
+};
+
+enum orangefs_param_request_op {
+	ORANGEFS_PARAM_REQUEST_OP_ACACHE_TIMEOUT_MSECS = 1,
+	ORANGEFS_PARAM_REQUEST_OP_ACACHE_HARD_LIMIT = 2,
+	ORANGEFS_PARAM_REQUEST_OP_ACACHE_SOFT_LIMIT = 3,
+	ORANGEFS_PARAM_REQUEST_OP_ACACHE_RECLAIM_PERCENTAGE = 4,
+	ORANGEFS_PARAM_REQUEST_OP_PERF_TIME_INTERVAL_SECS = 5,
+	ORANGEFS_PARAM_REQUEST_OP_PERF_HISTORY_SIZE = 6,
+	ORANGEFS_PARAM_REQUEST_OP_PERF_RESET = 7,
+	ORANGEFS_PARAM_REQUEST_OP_NCACHE_TIMEOUT_MSECS = 8,
+	ORANGEFS_PARAM_REQUEST_OP_NCACHE_HARD_LIMIT = 9,
+	ORANGEFS_PARAM_REQUEST_OP_NCACHE_SOFT_LIMIT = 10,
+	ORANGEFS_PARAM_REQUEST_OP_NCACHE_RECLAIM_PERCENTAGE = 11,
+	ORANGEFS_PARAM_REQUEST_OP_STATIC_ACACHE_TIMEOUT_MSECS = 12,
+	ORANGEFS_PARAM_REQUEST_OP_STATIC_ACACHE_HARD_LIMIT = 13,
+	ORANGEFS_PARAM_REQUEST_OP_STATIC_ACACHE_SOFT_LIMIT = 14,
+	ORANGEFS_PARAM_REQUEST_OP_STATIC_ACACHE_RECLAIM_PERCENTAGE = 15,
+	ORANGEFS_PARAM_REQUEST_OP_CLIENT_DEBUG = 16,
+	ORANGEFS_PARAM_REQUEST_OP_CCACHE_TIMEOUT_SECS = 17,
+	ORANGEFS_PARAM_REQUEST_OP_CCACHE_HARD_LIMIT = 18,
+	ORANGEFS_PARAM_REQUEST_OP_CCACHE_SOFT_LIMIT = 19,
+	ORANGEFS_PARAM_REQUEST_OP_CCACHE_RECLAIM_PERCENTAGE = 20,
+	ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_TIMEOUT_SECS = 21,
+	ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_HARD_LIMIT = 22,
+	ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_SOFT_LIMIT = 23,
+	ORANGEFS_PARAM_REQUEST_OP_CAPCACHE_RECLAIM_PERCENTAGE = 24,
+	ORANGEFS_PARAM_REQUEST_OP_TWO_MASK_VALUES = 25,
+	ORANGEFS_PARAM_REQUEST_OP_READAHEAD_SIZE = 26,
+	ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT = 27,
+	ORANGEFS_PARAM_REQUEST_OP_READAHEAD_COUNT_SIZE = 28,
+	ORANGEFS_PARAM_REQUEST_OP_READAHEAD_READCNT = 29,
+};
+
+struct orangefs_param_request_s {
+	enum orangefs_param_request_type type;
+	enum orangefs_param_request_op op;
+	union {
+		__s64 value64;
+		__s32 value32[2];
+	} u;
+	char s_value[ORANGEFS_MAX_DEBUG_STRING_LEN];
+};
+
+enum orangefs_perf_count_request_type {
+	ORANGEFS_PERF_COUNT_REQUEST_ACACHE = 1,
+	ORANGEFS_PERF_COUNT_REQUEST_NCACHE = 2,
+	ORANGEFS_PERF_COUNT_REQUEST_CAPCACHE = 3,
+};
+
+struct orangefs_perf_count_request_s {
+	enum orangefs_perf_count_request_type type;
+	__s32 __pad1;
+};
+
+struct orangefs_fs_key_request_s {
+	__s32 fsid;
+	__s32 __pad1;
+};
+
+/* 2.9.6 */
+struct orangefs_features_request_s {
+	__u64 features;
+};
+
+struct orangefs_upcall_s {
+	__s32 type;
+	__u32 uid;
+	__u32 gid;
+	int pid;
+	int tgid;
+	/* Trailers unused but must be retained for protocol compatibility. */
+	__s64 trailer_size;
+	char *trailer_buf;
+
+	union {
+		struct orangefs_io_request_s io;
+		struct orangefs_lookup_request_s lookup;
+		struct orangefs_create_request_s create;
+		struct orangefs_symlink_request_s sym;
+		struct orangefs_getattr_request_s getattr;
+		struct orangefs_setattr_request_s setattr;
+		struct orangefs_remove_request_s remove;
+		struct orangefs_mkdir_request_s mkdir;
+		struct orangefs_readdir_request_s readdir;
+		struct orangefs_readdirplus_request_s readdirplus;
+		struct orangefs_rename_request_s rename;
+		struct orangefs_statfs_request_s statfs;
+		struct orangefs_truncate_request_s truncate;
+		struct orangefs_ra_cache_flush_request_s ra_cache_flush;
+		struct orangefs_fs_mount_request_s fs_mount;
+		struct orangefs_fs_umount_request_s fs_umount;
+		struct orangefs_getxattr_request_s getxattr;
+		struct orangefs_setxattr_request_s setxattr;
+		struct orangefs_listxattr_request_s listxattr;
+		struct orangefs_removexattr_request_s removexattr;
+		struct orangefs_op_cancel_s cancel;
+		struct orangefs_fsync_request_s fsync;
+		struct orangefs_param_request_s param;
+		struct orangefs_perf_count_request_s perf_count;
+		struct orangefs_fs_key_request_s fs_key;
+		struct orangefs_features_request_s features;
+	} req;
+};
+
+#endif /* __UPCALL_H */
diff --git a/fs/orangefs/waitqueue.c b/fs/orangefs/waitqueue.c
new file mode 100644
index 000000000..beafc33d5
--- /dev/null
+++ b/fs/orangefs/waitqueue.c
@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * (C) 2011 Omnibond Systems
+ *
+ * Changes by Acxiom Corporation to implement generic service_operation()
+ * function, Copyright Acxiom Corporation, 2005.
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  In-kernel waitqueue operations.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+
+static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op,
+		long timeout,
+		int flags)
+			__acquires(op->lock);
+static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
+	__releases(op->lock);
+
+/*
+ * What we do in this function is to walk the list of operations that are
+ * present in the request queue and mark them as purged.
+ * NOTE: This is called from the device close after client-core has
+ * guaranteed that no new operations could appear on the list since the
+ * client-core is anyway going to exit.
+ */
+void purge_waiting_ops(void)
+{
+	struct orangefs_kernel_op_s *op, *tmp;
+
+	spin_lock(&orangefs_request_list_lock);
+	list_for_each_entry_safe(op, tmp, &orangefs_request_list, list) {
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "pvfs2-client-core: purging op tag %llu %s\n",
+			     llu(op->tag),
+			     get_opname_string(op));
+		set_op_state_purged(op);
+		gossip_debug(GOSSIP_DEV_DEBUG,
+			     "%s: op:%s: op_state:%d: process:%s:\n",
+			     __func__,
+			     get_opname_string(op),
+			     op->op_state,
+			     current->comm);
+	}
+	spin_unlock(&orangefs_request_list_lock);
+}
+
+/*
+ * submits a ORANGEFS operation and waits for it to complete
+ *
+ * Note op->downcall.status will contain the status of the operation (in
+ * errno format), whether provided by pvfs2-client or a result of failure to
+ * service the operation.  If the caller wishes to distinguish, then
+ * op->state can be checked to see if it was serviced or not.
+ *
+ * Returns contents of op->downcall.status for convenience
+ */
+int service_operation(struct orangefs_kernel_op_s *op,
+		      const char *op_name,
+		      int flags)
+{
+	long timeout = MAX_SCHEDULE_TIMEOUT;
+	int ret = 0;
+
+	DEFINE_WAIT(wait_entry);
+
+	op->upcall.tgid = current->tgid;
+	op->upcall.pid = current->pid;
+
+retry_servicing:
+	op->downcall.status = 0;
+	gossip_debug(GOSSIP_WAIT_DEBUG,
+		     "%s: %s op:%p: process:%s: pid:%d:\n",
+		     __func__,
+		     op_name,
+		     op,
+		     current->comm,
+		     current->pid);
+
+	/*
+	 * If ORANGEFS_OP_NO_MUTEX was set in flags, we need to avoid
+	 * acquiring the request_mutex because we're servicing a
+	 * high priority remount operation and the request_mutex is
+	 * already taken.
+	 */
+	if (!(flags & ORANGEFS_OP_NO_MUTEX)) {
+		if (flags & ORANGEFS_OP_INTERRUPTIBLE)
+			ret = mutex_lock_interruptible(&orangefs_request_mutex);
+		else
+			ret = mutex_lock_killable(&orangefs_request_mutex);
+		/*
+		 * check to see if we were interrupted while waiting for
+		 * mutex
+		 */
+		if (ret < 0) {
+			op->downcall.status = ret;
+			gossip_debug(GOSSIP_WAIT_DEBUG,
+				     "%s: service_operation interrupted.\n",
+				     __func__);
+			return ret;
+		}
+	}
+
+	/* queue up the operation */
+	spin_lock(&orangefs_request_list_lock);
+	spin_lock(&op->lock);
+	set_op_state_waiting(op);
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "%s: op:%s: op_state:%d: process:%s:\n",
+		     __func__,
+		     get_opname_string(op),
+		     op->op_state,
+		     current->comm);
+	/* add high priority remount op to the front of the line. */
+	if (flags & ORANGEFS_OP_PRIORITY)
+		list_add(&op->list, &orangefs_request_list);
+	else
+		list_add_tail(&op->list, &orangefs_request_list);
+	spin_unlock(&op->lock);
+	wake_up_interruptible(&orangefs_request_list_waitq);
+	if (!__is_daemon_in_service()) {
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "%s:client core is NOT in service.\n",
+			     __func__);
+		/*
+		 * Don't wait for the userspace component to return if
+		 * the filesystem is being umounted anyway.
+		 */
+		if (op->upcall.type == ORANGEFS_VFS_OP_FS_UMOUNT)
+			timeout = 0;
+		else
+			timeout = op_timeout_secs * HZ;
+	}
+	spin_unlock(&orangefs_request_list_lock);
+
+	if (!(flags & ORANGEFS_OP_NO_MUTEX))
+		mutex_unlock(&orangefs_request_mutex);
+
+	ret = wait_for_matching_downcall(op, timeout, flags);
+	gossip_debug(GOSSIP_WAIT_DEBUG,
+		     "%s: wait_for_matching_downcall returned %d for %p\n",
+		     __func__,
+		     ret,
+		     op);
+
+	/* got matching downcall; make sure status is in errno format */
+	if (!ret) {
+		spin_unlock(&op->lock);
+		op->downcall.status =
+		    orangefs_normalize_to_errno(op->downcall.status);
+		ret = op->downcall.status;
+		goto out;
+	}
+
+	/* failed to get matching downcall */
+	if (ret == -ETIMEDOUT) {
+		gossip_err("%s: %s -- wait timed out; aborting attempt.\n",
+			   __func__,
+			   op_name);
+	}
+
+	/*
+	 * remove a waiting op from the request list or
+	 * remove an in-progress op from the in-progress list.
+	 */
+	orangefs_clean_up_interrupted_operation(op);
+
+	op->downcall.status = ret;
+	/* retry if operation has not been serviced and if requested */
+	if (ret == -EAGAIN) {
+		op->attempts++;
+		timeout = op_timeout_secs * HZ;
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "orangefs: tag %llu (%s)"
+			     " -- operation to be retried (%d attempt)\n",
+			     llu(op->tag),
+			     op_name,
+			     op->attempts);
+
+		/*
+		 * io ops (ops that use the shared memory buffer) have
+		 * to be returned to their caller for a retry. Other ops
+		 * can just be recycled here.
+		 */
+		if (!op->uses_shared_memory)
+			goto retry_servicing;
+	}
+
+out:
+	gossip_debug(GOSSIP_WAIT_DEBUG,
+		     "%s: %s returning: %d for %p.\n",
+		     __func__,
+		     op_name,
+		     ret,
+		     op);
+	return ret;
+}
+
+/* This can get called on an I/O op if it had a bad service_operation. */
+bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op)
+{
+	u64 tag = op->tag;
+	if (!op_state_in_progress(op))
+		return false;
+
+	op->slot_to_free = op->upcall.req.io.buf_index;
+	memset(&op->upcall, 0, sizeof(op->upcall));
+	memset(&op->downcall, 0, sizeof(op->downcall));
+	op->upcall.type = ORANGEFS_VFS_OP_CANCEL;
+	op->upcall.req.cancel.op_tag = tag;
+	op->downcall.type = ORANGEFS_VFS_OP_INVALID;
+	op->downcall.status = -1;
+	orangefs_new_tag(op);
+
+	spin_lock(&orangefs_request_list_lock);
+	/* orangefs_request_list_lock is enough of a barrier here */
+	if (!__is_daemon_in_service()) {
+		spin_unlock(&orangefs_request_list_lock);
+		return false;
+	}
+	spin_lock(&op->lock);
+	set_op_state_waiting(op);
+	gossip_debug(GOSSIP_DEV_DEBUG,
+		     "%s: op:%s: op_state:%d: process:%s:\n",
+		     __func__,
+		     get_opname_string(op),
+		     op->op_state,
+		     current->comm);
+	list_add(&op->list, &orangefs_request_list);
+	spin_unlock(&op->lock);
+	spin_unlock(&orangefs_request_list_lock);
+
+	gossip_debug(GOSSIP_WAIT_DEBUG,
+		     "Attempting ORANGEFS operation cancellation of tag %llu\n",
+		     llu(tag));
+	return true;
+}
+
+/*
+ * Change an op to the "given up" state and remove it from its list.
+ */
+static void
+	orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op)
+		__releases(op->lock)
+{
+	/*
+	 * handle interrupted cases depending on what state we were in when
+	 * the interruption is detected.
+	 *
+	 * Called with op->lock held.
+	 */
+
+	/*
+	 * List manipulation code elsewhere will ignore ops that
+	 * have been given up upon.
+	 */
+	op->op_state |= OP_VFS_STATE_GIVEN_UP;
+
+	if (list_empty(&op->list)) {
+		/* caught copying to/from daemon */
+		BUG_ON(op_state_serviced(op));
+		spin_unlock(&op->lock);
+		wait_for_completion(&op->waitq);
+	} else if (op_state_waiting(op)) {
+		/*
+		 * upcall hasn't been read; remove op from upcall request
+		 * list.
+		 */
+		spin_unlock(&op->lock);
+		spin_lock(&orangefs_request_list_lock);
+		list_del_init(&op->list);
+		spin_unlock(&orangefs_request_list_lock);
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "Interrupted: Removed op %p from request_list\n",
+			     op);
+	} else if (op_state_in_progress(op)) {
+		/* op must be removed from the in progress htable */
+		spin_unlock(&op->lock);
+		spin_lock(&orangefs_htable_ops_in_progress_lock);
+		list_del_init(&op->list);
+		spin_unlock(&orangefs_htable_ops_in_progress_lock);
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "Interrupted: Removed op %p"
+			     " from htable_ops_in_progress\n",
+			     op);
+	} else {
+		spin_unlock(&op->lock);
+		gossip_err("interrupted operation is in a weird state 0x%x\n",
+			   op->op_state);
+	}
+	reinit_completion(&op->waitq);
+}
+
+/*
+ * Sleeps on waitqueue waiting for matching downcall.
+ * If client-core finishes servicing, then we are good to go.
+ * else if client-core exits, we get woken up here, and retry with a timeout
+ *
+ * When this call returns to the caller, the specified op will no
+ * longer be in either the in_progress hash table or on the request list.
+ *
+ * Returns 0 on success and -errno on failure
+ * Errors are:
+ * EAGAIN in case we want the caller to requeue and try again..
+ * EINTR/EIO/ETIMEDOUT indicating we are done trying to service this
+ * operation since client-core seems to be exiting too often
+ * or if we were interrupted.
+ *
+ * Returns with op->lock taken.
+ */
+static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op,
+		long timeout,
+		int flags)
+			__acquires(op->lock)
+{
+	long n;
+	int writeback = flags & ORANGEFS_OP_WRITEBACK,
+	    interruptible = flags & ORANGEFS_OP_INTERRUPTIBLE;
+
+	/*
+	 * There's a "schedule_timeout" inside of these wait
+	 * primitives, during which the op is out of the hands of the
+	 * user process that needs something done and is being
+	 * manipulated by the client-core process.
+	 */
+	if (writeback)
+		n = wait_for_completion_io_timeout(&op->waitq, timeout);
+	else if (!writeback && interruptible)
+		n = wait_for_completion_interruptible_timeout(&op->waitq,
+								      timeout);
+	else /* !writeback && !interruptible but compiler complains */
+		n = wait_for_completion_killable_timeout(&op->waitq, timeout);
+
+	spin_lock(&op->lock);
+
+	if (op_state_serviced(op))
+		return 0;
+
+	if (unlikely(n < 0)) {
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "%s: operation interrupted, tag %llu, %p\n",
+			     __func__,
+			     llu(op->tag),
+			     op);
+		return -EINTR;
+	}
+	if (op_state_purged(op)) {
+		gossip_debug(GOSSIP_WAIT_DEBUG,
+			     "%s: operation purged, tag %llu, %p, %d\n",
+			     __func__,
+			     llu(op->tag),
+			     op,
+			     op->attempts);
+		return (op->attempts < ORANGEFS_PURGE_RETRY_COUNT) ?
+			 -EAGAIN :
+			 -EIO;
+	}
+	/* must have timed out, then... */
+	gossip_debug(GOSSIP_WAIT_DEBUG,
+		     "%s: operation timed out, tag %llu, %p, %d)\n",
+		     __func__,
+		     llu(op->tag),
+		     op,
+		     op->attempts);
+	return -ETIMEDOUT;
+}
diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c
new file mode 100644
index 000000000..9a5b757fb
--- /dev/null
+++ b/fs/orangefs/xattr.c
@@ -0,0 +1,562 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) 2001 Clemson University and The University of Chicago
+ * Copyright 2018 Omnibond Systems, L.L.C.
+ *
+ * See COPYING in top-level directory.
+ */
+
+/*
+ *  Linux VFS extended attribute operations.
+ */
+
+#include "protocol.h"
+#include "orangefs-kernel.h"
+#include "orangefs-bufmap.h"
+#include <linux/posix_acl_xattr.h>
+#include <linux/xattr.h>
+#include <linux/hashtable.h>
+
+#define SYSTEM_ORANGEFS_KEY "system.pvfs2."
+#define SYSTEM_ORANGEFS_KEY_LEN 13
+
+/*
+ * this function returns
+ *   0 if the key corresponding to name is not meant to be printed as part
+ *     of a listxattr.
+ *   1 if the key corresponding to name is meant to be returned as part of
+ *     a listxattr.
+ * The ones that start SYSTEM_ORANGEFS_KEY are the ones to avoid printing.
+ */
+static int is_reserved_key(const char *key, size_t size)
+{
+
+	if (size < SYSTEM_ORANGEFS_KEY_LEN)
+		return 1;
+
+	return strncmp(key, SYSTEM_ORANGEFS_KEY, SYSTEM_ORANGEFS_KEY_LEN) ?  1 : 0;
+}
+
+static inline int convert_to_internal_xattr_flags(int setxattr_flags)
+{
+	int internal_flag = 0;
+
+	if (setxattr_flags & XATTR_REPLACE) {
+		/* Attribute must exist! */
+		internal_flag = ORANGEFS_XATTR_REPLACE;
+	} else if (setxattr_flags & XATTR_CREATE) {
+		/* Attribute must not exist */
+		internal_flag = ORANGEFS_XATTR_CREATE;
+	}
+	return internal_flag;
+}
+
+static unsigned int xattr_key(const char *key)
+{
+	unsigned int i = 0;
+	while (key)
+		i += *key++;
+	return i % 16;
+}
+
+static struct orangefs_cached_xattr *find_cached_xattr(struct inode *inode,
+    const char *key)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_cached_xattr *cx;
+	struct hlist_head *h;
+	struct hlist_node *tmp;
+	h = &orangefs_inode->xattr_cache[xattr_key(key)];
+	if (hlist_empty(h))
+		return NULL;
+	hlist_for_each_entry_safe(cx, tmp, h, node) {
+/*		if (!time_before(jiffies, cx->timeout)) {
+			hlist_del(&cx->node);
+			kfree(cx);
+			continue;
+		}*/
+		if (!strcmp(cx->key, key))
+			return cx;
+	}
+	return NULL;
+}
+
+/*
+ * Tries to get a specified key's attributes of a given
+ * file into a user-specified buffer. Note that the getxattr
+ * interface allows for the users to probe the size of an
+ * extended attribute by passing in a value of 0 to size.
+ * Thus our return value is always the size of the attribute
+ * unless the key does not exist for the file and/or if
+ * there were errors in fetching the attribute value.
+ */
+ssize_t orangefs_inode_getxattr(struct inode *inode, const char *name,
+				void *buffer, size_t size)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op = NULL;
+	struct orangefs_cached_xattr *cx;
+	ssize_t ret = -ENOMEM;
+	ssize_t length = 0;
+	int fsuid;
+	int fsgid;
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "%s: name %s, buffer_size %zd\n",
+		     __func__, name, size);
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+		return -EINVAL;
+
+	fsuid = from_kuid(&init_user_ns, current_fsuid());
+	fsgid = from_kgid(&init_user_ns, current_fsgid());
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "getxattr on inode %pU, name %s "
+		     "(uid %o, gid %o)\n",
+		     get_khandle_from_ino(inode),
+		     name,
+		     fsuid,
+		     fsgid);
+
+	down_read(&orangefs_inode->xattr_sem);
+
+	cx = find_cached_xattr(inode, name);
+	if (cx && time_before(jiffies, cx->timeout)) {
+		if (cx->length == -1) {
+			ret = -ENODATA;
+			goto out_unlock;
+		} else {
+			if (size == 0) {
+				ret = cx->length;
+				goto out_unlock;
+			}
+			if (cx->length > size) {
+				ret = -ERANGE;
+				goto out_unlock;
+			}
+			memcpy(buffer, cx->val, cx->length);
+			memset(buffer + cx->length, 0, size - cx->length);
+			ret = cx->length;
+			goto out_unlock;
+		}
+	}
+
+	new_op = op_alloc(ORANGEFS_VFS_OP_GETXATTR);
+	if (!new_op)
+		goto out_unlock;
+
+	new_op->upcall.req.getxattr.refn = orangefs_inode->refn;
+	strcpy(new_op->upcall.req.getxattr.key, name);
+
+	/*
+	 * NOTE: Although keys are meant to be NULL terminated textual
+	 * strings, I am going to explicitly pass the length just in case
+	 * we change this later on...
+	 */
+	new_op->upcall.req.getxattr.key_sz = strlen(name) + 1;
+
+	ret = service_operation(new_op, "orangefs_inode_getxattr",
+				get_interruptible_flag(inode));
+	if (ret != 0) {
+		if (ret == -ENOENT) {
+			ret = -ENODATA;
+			gossip_debug(GOSSIP_XATTR_DEBUG,
+				     "orangefs_inode_getxattr: inode %pU key %s"
+				     " does not exist!\n",
+				     get_khandle_from_ino(inode),
+				     (char *)new_op->upcall.req.getxattr.key);
+			cx = kmalloc(sizeof *cx, GFP_KERNEL);
+			if (cx) {
+				strcpy(cx->key, name);
+				cx->length = -1;
+				cx->timeout = jiffies +
+				    orangefs_getattr_timeout_msecs*HZ/1000;
+				hash_add(orangefs_inode->xattr_cache, &cx->node,
+				    xattr_key(cx->key));
+			}
+		}
+		goto out_release_op;
+	}
+
+	/*
+	 * Length returned includes null terminator.
+	 */
+	length = new_op->downcall.resp.getxattr.val_sz;
+
+	/*
+	 * Just return the length of the queried attribute.
+	 */
+	if (size == 0) {
+		ret = length;
+		goto out_release_op;
+	}
+
+	/*
+	 * Check to see if key length is > provided buffer size.
+	 */
+	if (length > size) {
+		ret = -ERANGE;
+		goto out_release_op;
+	}
+
+	memcpy(buffer, new_op->downcall.resp.getxattr.val, length);
+	memset(buffer + length, 0, size - length);
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+	     "orangefs_inode_getxattr: inode %pU "
+	     "key %s key_sz %d, val_len %d\n",
+	     get_khandle_from_ino(inode),
+	     (char *)new_op->
+		upcall.req.getxattr.key,
+		     (int)new_op->
+		upcall.req.getxattr.key_sz,
+	     (int)ret);
+
+	ret = length;
+
+	if (cx) {
+		strcpy(cx->key, name);
+		memcpy(cx->val, buffer, length);
+		cx->length = length;
+		cx->timeout = jiffies + HZ;
+	} else {
+		cx = kmalloc(sizeof *cx, GFP_KERNEL);
+		if (cx) {
+			strcpy(cx->key, name);
+			memcpy(cx->val, buffer, length);
+			cx->length = length;
+			cx->timeout = jiffies + HZ;
+			hash_add(orangefs_inode->xattr_cache, &cx->node,
+			    xattr_key(cx->key));
+		}
+	}
+
+out_release_op:
+	op_release(new_op);
+out_unlock:
+	up_read(&orangefs_inode->xattr_sem);
+	return ret;
+}
+
+static int orangefs_inode_removexattr(struct inode *inode, const char *name,
+				      int flags)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op = NULL;
+	struct orangefs_cached_xattr *cx;
+	struct hlist_head *h;
+	struct hlist_node *tmp;
+	int ret = -ENOMEM;
+
+	if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+		return -EINVAL;
+
+	down_write(&orangefs_inode->xattr_sem);
+	new_op = op_alloc(ORANGEFS_VFS_OP_REMOVEXATTR);
+	if (!new_op)
+		goto out_unlock;
+
+	new_op->upcall.req.removexattr.refn = orangefs_inode->refn;
+	/*
+	 * NOTE: Although keys are meant to be NULL terminated
+	 * textual strings, I am going to explicitly pass the
+	 * length just in case we change this later on...
+	 */
+	strcpy(new_op->upcall.req.removexattr.key, name);
+	new_op->upcall.req.removexattr.key_sz = strlen(name) + 1;
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "orangefs_inode_removexattr: key %s, key_sz %d\n",
+		     (char *)new_op->upcall.req.removexattr.key,
+		     (int)new_op->upcall.req.removexattr.key_sz);
+
+	ret = service_operation(new_op,
+				"orangefs_inode_removexattr",
+				get_interruptible_flag(inode));
+	if (ret == -ENOENT) {
+		/*
+		 * Request to replace a non-existent attribute is an error.
+		 */
+		if (flags & XATTR_REPLACE)
+			ret = -ENODATA;
+		else
+			ret = 0;
+	}
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "orangefs_inode_removexattr: returning %d\n", ret);
+
+	op_release(new_op);
+
+	h = &orangefs_inode->xattr_cache[xattr_key(name)];
+	hlist_for_each_entry_safe(cx, tmp, h, node) {
+		if (!strcmp(cx->key, name)) {
+			hlist_del(&cx->node);
+			kfree(cx);
+			break;
+		}
+	}
+
+out_unlock:
+	up_write(&orangefs_inode->xattr_sem);
+	return ret;
+}
+
+/*
+ * Tries to set an attribute for a given key on a file.
+ *
+ * Returns a -ve number on error and 0 on success.  Key is text, but value
+ * can be binary!
+ */
+int orangefs_inode_setxattr(struct inode *inode, const char *name,
+			    const void *value, size_t size, int flags)
+{
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	int internal_flag = 0;
+	struct orangefs_cached_xattr *cx;
+	struct hlist_head *h;
+	struct hlist_node *tmp;
+	int ret = -ENOMEM;
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "%s: name %s, buffer_size %zd\n",
+		     __func__, name, size);
+
+	if (size > ORANGEFS_MAX_XATTR_VALUELEN)
+		return -EINVAL;
+	if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN)
+		return -EINVAL;
+
+	internal_flag = convert_to_internal_xattr_flags(flags);
+
+	/* This is equivalent to a removexattr */
+	if (size == 0 && !value) {
+		gossip_debug(GOSSIP_XATTR_DEBUG,
+			     "removing xattr (%s)\n",
+			     name);
+		return orangefs_inode_removexattr(inode, name, flags);
+	}
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "setxattr on inode %pU, name %s\n",
+		     get_khandle_from_ino(inode),
+		     name);
+
+	down_write(&orangefs_inode->xattr_sem);
+	new_op = op_alloc(ORANGEFS_VFS_OP_SETXATTR);
+	if (!new_op)
+		goto out_unlock;
+
+
+	new_op->upcall.req.setxattr.refn = orangefs_inode->refn;
+	new_op->upcall.req.setxattr.flags = internal_flag;
+	/*
+	 * NOTE: Although keys are meant to be NULL terminated textual
+	 * strings, I am going to explicitly pass the length just in
+	 * case we change this later on...
+	 */
+	strcpy(new_op->upcall.req.setxattr.keyval.key, name);
+	new_op->upcall.req.setxattr.keyval.key_sz = strlen(name) + 1;
+	memcpy(new_op->upcall.req.setxattr.keyval.val, value, size);
+	new_op->upcall.req.setxattr.keyval.val_sz = size;
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "orangefs_inode_setxattr: key %s, key_sz %d "
+		     " value size %zd\n",
+		     (char *)new_op->upcall.req.setxattr.keyval.key,
+		     (int)new_op->upcall.req.setxattr.keyval.key_sz,
+		     size);
+
+	ret = service_operation(new_op,
+				"orangefs_inode_setxattr",
+				get_interruptible_flag(inode));
+
+	gossip_debug(GOSSIP_XATTR_DEBUG,
+		     "orangefs_inode_setxattr: returning %d\n",
+		     ret);
+
+	/* when request is serviced properly, free req op struct */
+	op_release(new_op);
+
+	h = &orangefs_inode->xattr_cache[xattr_key(name)];
+	hlist_for_each_entry_safe(cx, tmp, h, node) {
+		if (!strcmp(cx->key, name)) {
+			hlist_del(&cx->node);
+			kfree(cx);
+			break;
+		}
+	}
+
+out_unlock:
+	up_write(&orangefs_inode->xattr_sem);
+	return ret;
+}
+
+/*
+ * Tries to get a specified object's keys into a user-specified buffer of a
+ * given size.  Note that like the previous instances of xattr routines, this
+ * also allows you to pass in a NULL pointer and 0 size to probe the size for
+ * subsequent memory allocations. Thus our return value is always the size of
+ * all the keys unless there were errors in fetching the keys!
+ */
+ssize_t orangefs_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
+	struct orangefs_kernel_op_s *new_op;
+	__u64 token = ORANGEFS_ITERATE_START;
+	ssize_t ret = -ENOMEM;
+	ssize_t total = 0;
+	int count_keys = 0;
+	int key_size;
+	int i = 0;
+	int returned_count = 0;
+
+	if (size > 0 && !buffer) {
+		gossip_err("%s: bogus NULL pointers\n", __func__);
+		return -EINVAL;
+	}
+
+	down_read(&orangefs_inode->xattr_sem);
+	new_op = op_alloc(ORANGEFS_VFS_OP_LISTXATTR);
+	if (!new_op)
+		goto out_unlock;
+
+	if (buffer && size > 0)
+		memset(buffer, 0, size);
+
+try_again:
+	key_size = 0;
+	new_op->upcall.req.listxattr.refn = orangefs_inode->refn;
+	new_op->upcall.req.listxattr.token = token;
+	new_op->upcall.req.listxattr.requested_count =
+	    (size == 0) ? 0 : ORANGEFS_MAX_XATTR_LISTLEN;
+	ret = service_operation(new_op, __func__,
+				get_interruptible_flag(inode));
+	if (ret != 0)
+		goto done;
+
+	if (size == 0) {
+		/*
+		 * This is a bit of a big upper limit, but I did not want to
+		 * spend too much time getting this correct, since users end
+		 * up allocating memory rather than us...
+		 */
+		total = new_op->downcall.resp.listxattr.returned_count *
+			ORANGEFS_MAX_XATTR_NAMELEN;
+		goto done;
+	}
+
+	returned_count = new_op->downcall.resp.listxattr.returned_count;
+	if (returned_count < 0 ||
+	    returned_count > ORANGEFS_MAX_XATTR_LISTLEN) {
+		gossip_err("%s: impossible value for returned_count:%d:\n",
+		__func__,
+		returned_count);
+		ret = -EIO;
+		goto done;
+	}
+
+	/*
+	 * Check to see how much can be fit in the buffer. Fit only whole keys.
+	 */
+	for (i = 0; i < returned_count; i++) {
+		if (new_op->downcall.resp.listxattr.lengths[i] < 0 ||
+		    new_op->downcall.resp.listxattr.lengths[i] >
+		    ORANGEFS_MAX_XATTR_NAMELEN) {
+			gossip_err("%s: impossible value for lengths[%d]\n",
+			    __func__,
+			    new_op->downcall.resp.listxattr.lengths[i]);
+			ret = -EIO;
+			goto done;
+		}
+		if (total + new_op->downcall.resp.listxattr.lengths[i] > size)
+			goto done;
+
+		/*
+		 * Since many dumb programs try to setxattr() on our reserved
+		 * xattrs this is a feeble attempt at defeating those by not
+		 * listing them in the output of listxattr.. sigh
+		 */
+		if (is_reserved_key(new_op->downcall.resp.listxattr.key +
+				    key_size,
+				    new_op->downcall.resp.
+					listxattr.lengths[i])) {
+			gossip_debug(GOSSIP_XATTR_DEBUG, "Copying key %d -> %s\n",
+					i, new_op->downcall.resp.listxattr.key +
+						key_size);
+			memcpy(buffer + total,
+				new_op->downcall.resp.listxattr.key + key_size,
+				new_op->downcall.resp.listxattr.lengths[i]);
+			total += new_op->downcall.resp.listxattr.lengths[i];
+			count_keys++;
+		} else {
+			gossip_debug(GOSSIP_XATTR_DEBUG, "[RESERVED] key %d -> %s\n",
+					i, new_op->downcall.resp.listxattr.key +
+						key_size);
+		}
+		key_size += new_op->downcall.resp.listxattr.lengths[i];
+	}
+
+	/*
+	 * Since the buffer was large enough, we might have to continue
+	 * fetching more keys!
+	 */
+	token = new_op->downcall.resp.listxattr.token;
+	if (token != ORANGEFS_ITERATE_END)
+		goto try_again;
+
+done:
+	gossip_debug(GOSSIP_XATTR_DEBUG, "%s: returning %d"
+		     " [size of buffer %ld] (filled in %d keys)\n",
+		     __func__,
+		     ret ? (int)ret : (int)total,
+		     (long)size,
+		     count_keys);
+	op_release(new_op);
+	if (ret == 0)
+		ret = total;
+out_unlock:
+	up_read(&orangefs_inode->xattr_sem);
+	return ret;
+}
+
+static int orangefs_xattr_set_default(const struct xattr_handler *handler,
+				      struct user_namespace *mnt_userns,
+				      struct dentry *unused,
+				      struct inode *inode,
+				      const char *name,
+				      const void *buffer,
+				      size_t size,
+				      int flags)
+{
+	return orangefs_inode_setxattr(inode, name, buffer, size, flags);
+}
+
+static int orangefs_xattr_get_default(const struct xattr_handler *handler,
+				      struct dentry *unused,
+				      struct inode *inode,
+				      const char *name,
+				      void *buffer,
+				      size_t size)
+{
+	return orangefs_inode_getxattr(inode, name, buffer, size);
+
+}
+
+static const struct xattr_handler orangefs_xattr_default_handler = {
+	.prefix = "",  /* match any name => handlers called with full name */
+	.get = orangefs_xattr_get_default,
+	.set = orangefs_xattr_set_default,
+};
+
+const struct xattr_handler *orangefs_xattr_handlers[] = {
+	&posix_acl_access_xattr_handler,
+	&posix_acl_default_xattr_handler,
+	&orangefs_xattr_default_handler,
+	NULL
+};