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-rw-r--r--fs/ocfs2/dlmfs/Makefile5
-rw-r--r--fs/ocfs2/dlmfs/dlmfs.c689
-rw-r--r--fs/ocfs2/dlmfs/userdlm.c703
-rw-r--r--fs/ocfs2/dlmfs/userdlm.h113
4 files changed, 1510 insertions, 0 deletions
diff --git a/fs/ocfs2/dlmfs/Makefile b/fs/ocfs2/dlmfs/Makefile
new file mode 100644
index 000000000..33431a029
--- /dev/null
+++ b/fs/ocfs2/dlmfs/Makefile
@@ -0,0 +1,5 @@
+ccflags-y := -I$(src)/..
+
+obj-$(CONFIG_OCFS2_FS) += ocfs2_dlmfs.o
+
+ocfs2_dlmfs-objs := userdlm.o dlmfs.o
diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c
new file mode 100644
index 000000000..602c71f32
--- /dev/null
+++ b/fs/ocfs2/dlmfs/dlmfs.c
@@ -0,0 +1,689 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dlmfs.c
+ *
+ * Code which implements the kernel side of a minimal userspace
+ * interface to our DLM. This file handles the virtual file system
+ * used for communication with userspace. Credit should go to ramfs,
+ * which was a template for the fs side of this module.
+ *
+ * Copyright (C) 2003, 2004 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+/* Simple VFS hooks based on: */
+/*
+ * Resizable simple ram filesystem for Linux.
+ *
+ * Copyright (C) 2000 Linus Torvalds.
+ * 2000 Transmeta Corp.
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/backing-dev.h>
+#include <linux/poll.h>
+
+#include <linux/uaccess.h>
+
+#include "stackglue.h"
+#include "userdlm.h"
+
+#define MLOG_MASK_PREFIX ML_DLMFS
+#include "cluster/masklog.h"
+
+
+static const struct super_operations dlmfs_ops;
+static const struct file_operations dlmfs_file_operations;
+static const struct inode_operations dlmfs_dir_inode_operations;
+static const struct inode_operations dlmfs_root_inode_operations;
+static const struct inode_operations dlmfs_file_inode_operations;
+static struct kmem_cache *dlmfs_inode_cache;
+
+struct workqueue_struct *user_dlm_worker;
+
+
+
+/*
+ * These are the ABI capabilities of dlmfs.
+ *
+ * Over time, dlmfs has added some features that were not part of the
+ * initial ABI. Unfortunately, some of these features are not detectable
+ * via standard usage. For example, Linux's default poll always returns
+ * EPOLLIN, so there is no way for a caller of poll(2) to know when dlmfs
+ * added poll support. Instead, we provide this list of new capabilities.
+ *
+ * Capabilities is a read-only attribute. We do it as a module parameter
+ * so we can discover it whether dlmfs is built in, loaded, or even not
+ * loaded.
+ *
+ * The ABI features are local to this machine's dlmfs mount. This is
+ * distinct from the locking protocol, which is concerned with inter-node
+ * interaction.
+ *
+ * Capabilities:
+ * - bast : EPOLLIN against the file descriptor of a held lock
+ * signifies a bast fired on the lock.
+ */
+#define DLMFS_CAPABILITIES "bast stackglue"
+static int param_set_dlmfs_capabilities(const char *val,
+ const struct kernel_param *kp)
+{
+ printk(KERN_ERR "%s: readonly parameter\n", kp->name);
+ return -EINVAL;
+}
+static int param_get_dlmfs_capabilities(char *buffer,
+ const struct kernel_param *kp)
+{
+ return strlcpy(buffer, DLMFS_CAPABILITIES,
+ strlen(DLMFS_CAPABILITIES) + 1);
+}
+module_param_call(capabilities, param_set_dlmfs_capabilities,
+ param_get_dlmfs_capabilities, NULL, 0444);
+MODULE_PARM_DESC(capabilities, DLMFS_CAPABILITIES);
+
+
+/*
+ * decodes a set of open flags into a valid lock level and a set of flags.
+ * returns < 0 if we have invalid flags
+ * flags which mean something to us:
+ * O_RDONLY -> PRMODE level
+ * O_WRONLY -> EXMODE level
+ *
+ * O_NONBLOCK -> NOQUEUE
+ */
+static int dlmfs_decode_open_flags(int open_flags,
+ int *level,
+ int *flags)
+{
+ if (open_flags & (O_WRONLY|O_RDWR))
+ *level = DLM_LOCK_EX;
+ else
+ *level = DLM_LOCK_PR;
+
+ *flags = 0;
+ if (open_flags & O_NONBLOCK)
+ *flags |= DLM_LKF_NOQUEUE;
+
+ return 0;
+}
+
+static int dlmfs_file_open(struct inode *inode,
+ struct file *file)
+{
+ int status, level, flags;
+ struct dlmfs_filp_private *fp = NULL;
+ struct dlmfs_inode_private *ip;
+
+ if (S_ISDIR(inode->i_mode))
+ BUG();
+
+ mlog(0, "open called on inode %lu, flags 0x%x\n", inode->i_ino,
+ file->f_flags);
+
+ status = dlmfs_decode_open_flags(file->f_flags, &level, &flags);
+ if (status < 0)
+ goto bail;
+
+ /* We don't want to honor O_APPEND at read/write time as it
+ * doesn't make sense for LVB writes. */
+ file->f_flags &= ~O_APPEND;
+
+ fp = kmalloc(sizeof(*fp), GFP_NOFS);
+ if (!fp) {
+ status = -ENOMEM;
+ goto bail;
+ }
+ fp->fp_lock_level = level;
+
+ ip = DLMFS_I(inode);
+
+ status = user_dlm_cluster_lock(&ip->ip_lockres, level, flags);
+ if (status < 0) {
+ /* this is a strange error to return here but I want
+ * to be able userspace to be able to distinguish a
+ * valid lock request from one that simply couldn't be
+ * granted. */
+ if (flags & DLM_LKF_NOQUEUE && status == -EAGAIN)
+ status = -ETXTBSY;
+ kfree(fp);
+ goto bail;
+ }
+
+ file->private_data = fp;
+bail:
+ return status;
+}
+
+static int dlmfs_file_release(struct inode *inode,
+ struct file *file)
+{
+ int level, status;
+ struct dlmfs_inode_private *ip = DLMFS_I(inode);
+ struct dlmfs_filp_private *fp = file->private_data;
+
+ if (S_ISDIR(inode->i_mode))
+ BUG();
+
+ mlog(0, "close called on inode %lu\n", inode->i_ino);
+
+ status = 0;
+ if (fp) {
+ level = fp->fp_lock_level;
+ if (level != DLM_LOCK_IV)
+ user_dlm_cluster_unlock(&ip->ip_lockres, level);
+
+ kfree(fp);
+ file->private_data = NULL;
+ }
+
+ return 0;
+}
+
+/*
+ * We do ->setattr() just to override size changes. Our size is the size
+ * of the LVB and nothing else.
+ */
+static int dlmfs_file_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ int error;
+ struct inode *inode = d_inode(dentry);
+
+ attr->ia_valid &= ~ATTR_SIZE;
+ error = setattr_prepare(dentry, attr);
+ if (error)
+ return error;
+
+ setattr_copy(inode, attr);
+ mark_inode_dirty(inode);
+ return 0;
+}
+
+static __poll_t dlmfs_file_poll(struct file *file, poll_table *wait)
+{
+ __poll_t event = 0;
+ struct inode *inode = file_inode(file);
+ struct dlmfs_inode_private *ip = DLMFS_I(inode);
+
+ poll_wait(file, &ip->ip_lockres.l_event, wait);
+
+ spin_lock(&ip->ip_lockres.l_lock);
+ if (ip->ip_lockres.l_flags & USER_LOCK_BLOCKED)
+ event = EPOLLIN | EPOLLRDNORM;
+ spin_unlock(&ip->ip_lockres.l_lock);
+
+ return event;
+}
+
+static ssize_t dlmfs_file_read(struct file *filp,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ int bytes_left;
+ ssize_t readlen, got;
+ char *lvb_buf;
+ struct inode *inode = file_inode(filp);
+
+ mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",
+ inode->i_ino, count, *ppos);
+
+ if (*ppos >= i_size_read(inode))
+ return 0;
+
+ if (!count)
+ return 0;
+
+ if (!access_ok(VERIFY_WRITE, buf, count))
+ return -EFAULT;
+
+ /* don't read past the lvb */
+ if ((count + *ppos) > i_size_read(inode))
+ readlen = i_size_read(inode) - *ppos;
+ else
+ readlen = count;
+
+ lvb_buf = kmalloc(readlen, GFP_NOFS);
+ if (!lvb_buf)
+ return -ENOMEM;
+
+ got = user_dlm_read_lvb(inode, lvb_buf, readlen);
+ if (got) {
+ BUG_ON(got != readlen);
+ bytes_left = __copy_to_user(buf, lvb_buf, readlen);
+ readlen -= bytes_left;
+ } else
+ readlen = 0;
+
+ kfree(lvb_buf);
+
+ *ppos = *ppos + readlen;
+
+ mlog(0, "read %zd bytes\n", readlen);
+ return readlen;
+}
+
+static ssize_t dlmfs_file_write(struct file *filp,
+ const char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ int bytes_left;
+ ssize_t writelen;
+ char *lvb_buf;
+ struct inode *inode = file_inode(filp);
+
+ mlog(0, "inode %lu, count = %zu, *ppos = %llu\n",
+ inode->i_ino, count, *ppos);
+
+ if (*ppos >= i_size_read(inode))
+ return -ENOSPC;
+
+ if (!count)
+ return 0;
+
+ if (!access_ok(VERIFY_READ, buf, count))
+ return -EFAULT;
+
+ /* don't write past the lvb */
+ if ((count + *ppos) > i_size_read(inode))
+ writelen = i_size_read(inode) - *ppos;
+ else
+ writelen = count - *ppos;
+
+ lvb_buf = kmalloc(writelen, GFP_NOFS);
+ if (!lvb_buf)
+ return -ENOMEM;
+
+ bytes_left = copy_from_user(lvb_buf, buf, writelen);
+ writelen -= bytes_left;
+ if (writelen)
+ user_dlm_write_lvb(inode, lvb_buf, writelen);
+
+ kfree(lvb_buf);
+
+ *ppos = *ppos + writelen;
+ mlog(0, "wrote %zd bytes\n", writelen);
+ return writelen;
+}
+
+static void dlmfs_init_once(void *foo)
+{
+ struct dlmfs_inode_private *ip =
+ (struct dlmfs_inode_private *) foo;
+
+ ip->ip_conn = NULL;
+ ip->ip_parent = NULL;
+
+ inode_init_once(&ip->ip_vfs_inode);
+}
+
+static struct inode *dlmfs_alloc_inode(struct super_block *sb)
+{
+ struct dlmfs_inode_private *ip;
+
+ ip = kmem_cache_alloc(dlmfs_inode_cache, GFP_NOFS);
+ if (!ip)
+ return NULL;
+
+ return &ip->ip_vfs_inode;
+}
+
+static void dlmfs_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kmem_cache_free(dlmfs_inode_cache, DLMFS_I(inode));
+}
+
+static void dlmfs_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, dlmfs_i_callback);
+}
+
+static void dlmfs_evict_inode(struct inode *inode)
+{
+ int status;
+ struct dlmfs_inode_private *ip;
+
+ clear_inode(inode);
+
+ mlog(0, "inode %lu\n", inode->i_ino);
+
+ ip = DLMFS_I(inode);
+
+ if (S_ISREG(inode->i_mode)) {
+ status = user_dlm_destroy_lock(&ip->ip_lockres);
+ if (status < 0)
+ mlog_errno(status);
+ iput(ip->ip_parent);
+ goto clear_fields;
+ }
+
+ mlog(0, "we're a directory, ip->ip_conn = 0x%p\n", ip->ip_conn);
+ /* we must be a directory. If required, lets unregister the
+ * dlm context now. */
+ if (ip->ip_conn)
+ user_dlm_unregister(ip->ip_conn);
+clear_fields:
+ ip->ip_parent = NULL;
+ ip->ip_conn = NULL;
+}
+
+static struct inode *dlmfs_get_root_inode(struct super_block *sb)
+{
+ struct inode *inode = new_inode(sb);
+ umode_t mode = S_IFDIR | 0755;
+
+ if (inode) {
+ inode->i_ino = get_next_ino();
+ inode_init_owner(inode, NULL, mode);
+ inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
+ inc_nlink(inode);
+
+ inode->i_fop = &simple_dir_operations;
+ inode->i_op = &dlmfs_root_inode_operations;
+ }
+
+ return inode;
+}
+
+static struct inode *dlmfs_get_inode(struct inode *parent,
+ struct dentry *dentry,
+ umode_t mode)
+{
+ struct super_block *sb = parent->i_sb;
+ struct inode * inode = new_inode(sb);
+ struct dlmfs_inode_private *ip;
+
+ if (!inode)
+ return NULL;
+
+ inode->i_ino = get_next_ino();
+ inode_init_owner(inode, parent, mode);
+ inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
+
+ ip = DLMFS_I(inode);
+ ip->ip_conn = DLMFS_I(parent)->ip_conn;
+
+ switch (mode & S_IFMT) {
+ default:
+ /* for now we don't support anything other than
+ * directories and regular files. */
+ BUG();
+ break;
+ case S_IFREG:
+ inode->i_op = &dlmfs_file_inode_operations;
+ inode->i_fop = &dlmfs_file_operations;
+
+ i_size_write(inode, DLM_LVB_LEN);
+
+ user_dlm_lock_res_init(&ip->ip_lockres, dentry);
+
+ /* released at clear_inode time, this insures that we
+ * get to drop the dlm reference on each lock *before*
+ * we call the unregister code for releasing parent
+ * directories. */
+ ip->ip_parent = igrab(parent);
+ BUG_ON(!ip->ip_parent);
+ break;
+ case S_IFDIR:
+ inode->i_op = &dlmfs_dir_inode_operations;
+ inode->i_fop = &simple_dir_operations;
+
+ /* directory inodes start off with i_nlink ==
+ * 2 (for "." entry) */
+ inc_nlink(inode);
+ break;
+ }
+ return inode;
+}
+
+/*
+ * File creation. Allocate an inode, and we're done..
+ */
+/* SMP-safe */
+static int dlmfs_mkdir(struct inode * dir,
+ struct dentry * dentry,
+ umode_t mode)
+{
+ int status;
+ struct inode *inode = NULL;
+ const struct qstr *domain = &dentry->d_name;
+ struct dlmfs_inode_private *ip;
+ struct ocfs2_cluster_connection *conn;
+
+ mlog(0, "mkdir %.*s\n", domain->len, domain->name);
+
+ /* verify that we have a proper domain */
+ if (domain->len >= GROUP_NAME_MAX) {
+ status = -EINVAL;
+ mlog(ML_ERROR, "invalid domain name for directory.\n");
+ goto bail;
+ }
+
+ inode = dlmfs_get_inode(dir, dentry, mode | S_IFDIR);
+ if (!inode) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ ip = DLMFS_I(inode);
+
+ conn = user_dlm_register(domain);
+ if (IS_ERR(conn)) {
+ status = PTR_ERR(conn);
+ mlog(ML_ERROR, "Error %d could not register domain \"%.*s\"\n",
+ status, domain->len, domain->name);
+ goto bail;
+ }
+ ip->ip_conn = conn;
+
+ inc_nlink(dir);
+ d_instantiate(dentry, inode);
+ dget(dentry); /* Extra count - pin the dentry in core */
+
+ status = 0;
+bail:
+ if (status < 0)
+ iput(inode);
+ return status;
+}
+
+static int dlmfs_create(struct inode *dir,
+ struct dentry *dentry,
+ umode_t mode,
+ bool excl)
+{
+ int status = 0;
+ struct inode *inode;
+ const struct qstr *name = &dentry->d_name;
+
+ mlog(0, "create %.*s\n", name->len, name->name);
+
+ /* verify name is valid and doesn't contain any dlm reserved
+ * characters */
+ if (name->len >= USER_DLM_LOCK_ID_MAX_LEN ||
+ name->name[0] == '$') {
+ status = -EINVAL;
+ mlog(ML_ERROR, "invalid lock name, %.*s\n", name->len,
+ name->name);
+ goto bail;
+ }
+
+ inode = dlmfs_get_inode(dir, dentry, mode | S_IFREG);
+ if (!inode) {
+ status = -ENOMEM;
+ mlog_errno(status);
+ goto bail;
+ }
+
+ d_instantiate(dentry, inode);
+ dget(dentry); /* Extra count - pin the dentry in core */
+bail:
+ return status;
+}
+
+static int dlmfs_unlink(struct inode *dir,
+ struct dentry *dentry)
+{
+ int status;
+ struct inode *inode = d_inode(dentry);
+
+ mlog(0, "unlink inode %lu\n", inode->i_ino);
+
+ /* if there are no current holders, or none that are waiting
+ * to acquire a lock, this basically destroys our lockres. */
+ status = user_dlm_destroy_lock(&DLMFS_I(inode)->ip_lockres);
+ if (status < 0) {
+ mlog(ML_ERROR, "unlink %pd, error %d from destroy\n",
+ dentry, status);
+ goto bail;
+ }
+ status = simple_unlink(dir, dentry);
+bail:
+ return status;
+}
+
+static int dlmfs_fill_super(struct super_block * sb,
+ void * data,
+ int silent)
+{
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
+ sb->s_blocksize = PAGE_SIZE;
+ sb->s_blocksize_bits = PAGE_SHIFT;
+ sb->s_magic = DLMFS_MAGIC;
+ sb->s_op = &dlmfs_ops;
+ sb->s_root = d_make_root(dlmfs_get_root_inode(sb));
+ if (!sb->s_root)
+ return -ENOMEM;
+ return 0;
+}
+
+static const struct file_operations dlmfs_file_operations = {
+ .open = dlmfs_file_open,
+ .release = dlmfs_file_release,
+ .poll = dlmfs_file_poll,
+ .read = dlmfs_file_read,
+ .write = dlmfs_file_write,
+ .llseek = default_llseek,
+};
+
+static const struct inode_operations dlmfs_dir_inode_operations = {
+ .create = dlmfs_create,
+ .lookup = simple_lookup,
+ .unlink = dlmfs_unlink,
+};
+
+/* this way we can restrict mkdir to only the toplevel of the fs. */
+static const struct inode_operations dlmfs_root_inode_operations = {
+ .lookup = simple_lookup,
+ .mkdir = dlmfs_mkdir,
+ .rmdir = simple_rmdir,
+};
+
+static const struct super_operations dlmfs_ops = {
+ .statfs = simple_statfs,
+ .alloc_inode = dlmfs_alloc_inode,
+ .destroy_inode = dlmfs_destroy_inode,
+ .evict_inode = dlmfs_evict_inode,
+ .drop_inode = generic_delete_inode,
+};
+
+static const struct inode_operations dlmfs_file_inode_operations = {
+ .getattr = simple_getattr,
+ .setattr = dlmfs_file_setattr,
+};
+
+static struct dentry *dlmfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_nodev(fs_type, flags, data, dlmfs_fill_super);
+}
+
+static struct file_system_type dlmfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ocfs2_dlmfs",
+ .mount = dlmfs_mount,
+ .kill_sb = kill_litter_super,
+};
+MODULE_ALIAS_FS("ocfs2_dlmfs");
+
+static int __init init_dlmfs_fs(void)
+{
+ int status;
+ int cleanup_inode = 0, cleanup_worker = 0;
+
+ dlmfs_inode_cache = kmem_cache_create("dlmfs_inode_cache",
+ sizeof(struct dlmfs_inode_private),
+ 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD|SLAB_ACCOUNT),
+ dlmfs_init_once);
+ if (!dlmfs_inode_cache) {
+ status = -ENOMEM;
+ goto bail;
+ }
+ cleanup_inode = 1;
+
+ user_dlm_worker = alloc_workqueue("user_dlm", WQ_MEM_RECLAIM, 0);
+ if (!user_dlm_worker) {
+ status = -ENOMEM;
+ goto bail;
+ }
+ cleanup_worker = 1;
+
+ user_dlm_set_locking_protocol();
+ status = register_filesystem(&dlmfs_fs_type);
+bail:
+ if (status) {
+ if (cleanup_inode)
+ kmem_cache_destroy(dlmfs_inode_cache);
+ if (cleanup_worker)
+ destroy_workqueue(user_dlm_worker);
+ } else
+ printk("OCFS2 User DLM kernel interface loaded\n");
+ return status;
+}
+
+static void __exit exit_dlmfs_fs(void)
+{
+ unregister_filesystem(&dlmfs_fs_type);
+
+ destroy_workqueue(user_dlm_worker);
+
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(dlmfs_inode_cache);
+
+}
+
+MODULE_AUTHOR("Oracle");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("OCFS2 DLM-Filesystem");
+
+module_init(init_dlmfs_fs)
+module_exit(exit_dlmfs_fs)
diff --git a/fs/ocfs2/dlmfs/userdlm.c b/fs/ocfs2/dlmfs/userdlm.c
new file mode 100644
index 000000000..24dbbbf13
--- /dev/null
+++ b/fs/ocfs2/dlmfs/userdlm.c
@@ -0,0 +1,703 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * userdlm.c
+ *
+ * Code which implements the kernel side of a minimal userspace
+ * interface to our DLM.
+ *
+ * Many of the functions here are pared down versions of dlmglue.c
+ * functions.
+ *
+ * Copyright (C) 2003, 2004 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/signal.h>
+#include <linux/sched/signal.h>
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/crc32.h>
+
+#include "ocfs2_lockingver.h"
+#include "stackglue.h"
+#include "userdlm.h"
+
+#define MLOG_MASK_PREFIX ML_DLMFS
+#include "cluster/masklog.h"
+
+
+static inline struct user_lock_res *user_lksb_to_lock_res(struct ocfs2_dlm_lksb *lksb)
+{
+ return container_of(lksb, struct user_lock_res, l_lksb);
+}
+
+static inline int user_check_wait_flag(struct user_lock_res *lockres,
+ int flag)
+{
+ int ret;
+
+ spin_lock(&lockres->l_lock);
+ ret = lockres->l_flags & flag;
+ spin_unlock(&lockres->l_lock);
+
+ return ret;
+}
+
+static inline void user_wait_on_busy_lock(struct user_lock_res *lockres)
+
+{
+ wait_event(lockres->l_event,
+ !user_check_wait_flag(lockres, USER_LOCK_BUSY));
+}
+
+static inline void user_wait_on_blocked_lock(struct user_lock_res *lockres)
+
+{
+ wait_event(lockres->l_event,
+ !user_check_wait_flag(lockres, USER_LOCK_BLOCKED));
+}
+
+/* I heart container_of... */
+static inline struct ocfs2_cluster_connection *
+cluster_connection_from_user_lockres(struct user_lock_res *lockres)
+{
+ struct dlmfs_inode_private *ip;
+
+ ip = container_of(lockres,
+ struct dlmfs_inode_private,
+ ip_lockres);
+ return ip->ip_conn;
+}
+
+static struct inode *
+user_dlm_inode_from_user_lockres(struct user_lock_res *lockres)
+{
+ struct dlmfs_inode_private *ip;
+
+ ip = container_of(lockres,
+ struct dlmfs_inode_private,
+ ip_lockres);
+ return &ip->ip_vfs_inode;
+}
+
+static inline void user_recover_from_dlm_error(struct user_lock_res *lockres)
+{
+ spin_lock(&lockres->l_lock);
+ lockres->l_flags &= ~USER_LOCK_BUSY;
+ spin_unlock(&lockres->l_lock);
+}
+
+#define user_log_dlm_error(_func, _stat, _lockres) do { \
+ mlog(ML_ERROR, "Dlm error %d while calling %s on " \
+ "resource %.*s\n", _stat, _func, \
+ _lockres->l_namelen, _lockres->l_name); \
+} while (0)
+
+/* WARNING: This function lives in a world where the only three lock
+ * levels are EX, PR, and NL. It *will* have to be adjusted when more
+ * lock types are added. */
+static inline int user_highest_compat_lock_level(int level)
+{
+ int new_level = DLM_LOCK_EX;
+
+ if (level == DLM_LOCK_EX)
+ new_level = DLM_LOCK_NL;
+ else if (level == DLM_LOCK_PR)
+ new_level = DLM_LOCK_PR;
+ return new_level;
+}
+
+static void user_ast(struct ocfs2_dlm_lksb *lksb)
+{
+ struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
+ int status;
+
+ mlog(ML_BASTS, "AST fired for lockres %.*s, level %d => %d\n",
+ lockres->l_namelen, lockres->l_name, lockres->l_level,
+ lockres->l_requested);
+
+ spin_lock(&lockres->l_lock);
+
+ status = ocfs2_dlm_lock_status(&lockres->l_lksb);
+ if (status) {
+ mlog(ML_ERROR, "lksb status value of %u on lockres %.*s\n",
+ status, lockres->l_namelen, lockres->l_name);
+ spin_unlock(&lockres->l_lock);
+ return;
+ }
+
+ mlog_bug_on_msg(lockres->l_requested == DLM_LOCK_IV,
+ "Lockres %.*s, requested ivmode. flags 0x%x\n",
+ lockres->l_namelen, lockres->l_name, lockres->l_flags);
+
+ /* we're downconverting. */
+ if (lockres->l_requested < lockres->l_level) {
+ if (lockres->l_requested <=
+ user_highest_compat_lock_level(lockres->l_blocking)) {
+ lockres->l_blocking = DLM_LOCK_NL;
+ lockres->l_flags &= ~USER_LOCK_BLOCKED;
+ }
+ }
+
+ lockres->l_level = lockres->l_requested;
+ lockres->l_requested = DLM_LOCK_IV;
+ lockres->l_flags |= USER_LOCK_ATTACHED;
+ lockres->l_flags &= ~USER_LOCK_BUSY;
+
+ spin_unlock(&lockres->l_lock);
+
+ wake_up(&lockres->l_event);
+}
+
+static inline void user_dlm_grab_inode_ref(struct user_lock_res *lockres)
+{
+ struct inode *inode;
+ inode = user_dlm_inode_from_user_lockres(lockres);
+ if (!igrab(inode))
+ BUG();
+}
+
+static void user_dlm_unblock_lock(struct work_struct *work);
+
+static void __user_dlm_queue_lockres(struct user_lock_res *lockres)
+{
+ if (!(lockres->l_flags & USER_LOCK_QUEUED)) {
+ user_dlm_grab_inode_ref(lockres);
+
+ INIT_WORK(&lockres->l_work, user_dlm_unblock_lock);
+
+ queue_work(user_dlm_worker, &lockres->l_work);
+ lockres->l_flags |= USER_LOCK_QUEUED;
+ }
+}
+
+static void __user_dlm_cond_queue_lockres(struct user_lock_res *lockres)
+{
+ int queue = 0;
+
+ if (!(lockres->l_flags & USER_LOCK_BLOCKED))
+ return;
+
+ switch (lockres->l_blocking) {
+ case DLM_LOCK_EX:
+ if (!lockres->l_ex_holders && !lockres->l_ro_holders)
+ queue = 1;
+ break;
+ case DLM_LOCK_PR:
+ if (!lockres->l_ex_holders)
+ queue = 1;
+ break;
+ default:
+ BUG();
+ }
+
+ if (queue)
+ __user_dlm_queue_lockres(lockres);
+}
+
+static void user_bast(struct ocfs2_dlm_lksb *lksb, int level)
+{
+ struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
+
+ mlog(ML_BASTS, "BAST fired for lockres %.*s, blocking %d, level %d\n",
+ lockres->l_namelen, lockres->l_name, level, lockres->l_level);
+
+ spin_lock(&lockres->l_lock);
+ lockres->l_flags |= USER_LOCK_BLOCKED;
+ if (level > lockres->l_blocking)
+ lockres->l_blocking = level;
+
+ __user_dlm_queue_lockres(lockres);
+ spin_unlock(&lockres->l_lock);
+
+ wake_up(&lockres->l_event);
+}
+
+static void user_unlock_ast(struct ocfs2_dlm_lksb *lksb, int status)
+{
+ struct user_lock_res *lockres = user_lksb_to_lock_res(lksb);
+
+ mlog(ML_BASTS, "UNLOCK AST fired for lockres %.*s, flags 0x%x\n",
+ lockres->l_namelen, lockres->l_name, lockres->l_flags);
+
+ if (status)
+ mlog(ML_ERROR, "dlm returns status %d\n", status);
+
+ spin_lock(&lockres->l_lock);
+ /* The teardown flag gets set early during the unlock process,
+ * so test the cancel flag to make sure that this ast isn't
+ * for a concurrent cancel. */
+ if (lockres->l_flags & USER_LOCK_IN_TEARDOWN
+ && !(lockres->l_flags & USER_LOCK_IN_CANCEL)) {
+ lockres->l_level = DLM_LOCK_IV;
+ } else if (status == DLM_CANCELGRANT) {
+ /* We tried to cancel a convert request, but it was
+ * already granted. Don't clear the busy flag - the
+ * ast should've done this already. */
+ BUG_ON(!(lockres->l_flags & USER_LOCK_IN_CANCEL));
+ lockres->l_flags &= ~USER_LOCK_IN_CANCEL;
+ goto out_noclear;
+ } else {
+ BUG_ON(!(lockres->l_flags & USER_LOCK_IN_CANCEL));
+ /* Cancel succeeded, we want to re-queue */
+ lockres->l_requested = DLM_LOCK_IV; /* cancel an
+ * upconvert
+ * request. */
+ lockres->l_flags &= ~USER_LOCK_IN_CANCEL;
+ /* we want the unblock thread to look at it again
+ * now. */
+ if (lockres->l_flags & USER_LOCK_BLOCKED)
+ __user_dlm_queue_lockres(lockres);
+ }
+
+ lockres->l_flags &= ~USER_LOCK_BUSY;
+out_noclear:
+ spin_unlock(&lockres->l_lock);
+
+ wake_up(&lockres->l_event);
+}
+
+/*
+ * This is the userdlmfs locking protocol version.
+ *
+ * See fs/ocfs2/dlmglue.c for more details on locking versions.
+ */
+static struct ocfs2_locking_protocol user_dlm_lproto = {
+ .lp_max_version = {
+ .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
+ .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
+ },
+ .lp_lock_ast = user_ast,
+ .lp_blocking_ast = user_bast,
+ .lp_unlock_ast = user_unlock_ast,
+};
+
+static inline void user_dlm_drop_inode_ref(struct user_lock_res *lockres)
+{
+ struct inode *inode;
+ inode = user_dlm_inode_from_user_lockres(lockres);
+ iput(inode);
+}
+
+static void user_dlm_unblock_lock(struct work_struct *work)
+{
+ int new_level, status;
+ struct user_lock_res *lockres =
+ container_of(work, struct user_lock_res, l_work);
+ struct ocfs2_cluster_connection *conn =
+ cluster_connection_from_user_lockres(lockres);
+
+ mlog(0, "lockres %.*s\n", lockres->l_namelen, lockres->l_name);
+
+ spin_lock(&lockres->l_lock);
+
+ mlog_bug_on_msg(!(lockres->l_flags & USER_LOCK_QUEUED),
+ "Lockres %.*s, flags 0x%x\n",
+ lockres->l_namelen, lockres->l_name, lockres->l_flags);
+
+ /* notice that we don't clear USER_LOCK_BLOCKED here. If it's
+ * set, we want user_ast clear it. */
+ lockres->l_flags &= ~USER_LOCK_QUEUED;
+
+ /* It's valid to get here and no longer be blocked - if we get
+ * several basts in a row, we might be queued by the first
+ * one, the unblock thread might run and clear the queued
+ * flag, and finally we might get another bast which re-queues
+ * us before our ast for the downconvert is called. */
+ if (!(lockres->l_flags & USER_LOCK_BLOCKED)) {
+ mlog(ML_BASTS, "lockres %.*s USER_LOCK_BLOCKED\n",
+ lockres->l_namelen, lockres->l_name);
+ spin_unlock(&lockres->l_lock);
+ goto drop_ref;
+ }
+
+ if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
+ mlog(ML_BASTS, "lockres %.*s USER_LOCK_IN_TEARDOWN\n",
+ lockres->l_namelen, lockres->l_name);
+ spin_unlock(&lockres->l_lock);
+ goto drop_ref;
+ }
+
+ if (lockres->l_flags & USER_LOCK_BUSY) {
+ if (lockres->l_flags & USER_LOCK_IN_CANCEL) {
+ mlog(ML_BASTS, "lockres %.*s USER_LOCK_IN_CANCEL\n",
+ lockres->l_namelen, lockres->l_name);
+ spin_unlock(&lockres->l_lock);
+ goto drop_ref;
+ }
+
+ lockres->l_flags |= USER_LOCK_IN_CANCEL;
+ spin_unlock(&lockres->l_lock);
+
+ status = ocfs2_dlm_unlock(conn, &lockres->l_lksb,
+ DLM_LKF_CANCEL);
+ if (status)
+ user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
+ goto drop_ref;
+ }
+
+ /* If there are still incompat holders, we can exit safely
+ * without worrying about re-queueing this lock as that will
+ * happen on the last call to user_cluster_unlock. */
+ if ((lockres->l_blocking == DLM_LOCK_EX)
+ && (lockres->l_ex_holders || lockres->l_ro_holders)) {
+ spin_unlock(&lockres->l_lock);
+ mlog(ML_BASTS, "lockres %.*s, EX/PR Holders %u,%u\n",
+ lockres->l_namelen, lockres->l_name,
+ lockres->l_ex_holders, lockres->l_ro_holders);
+ goto drop_ref;
+ }
+
+ if ((lockres->l_blocking == DLM_LOCK_PR)
+ && lockres->l_ex_holders) {
+ spin_unlock(&lockres->l_lock);
+ mlog(ML_BASTS, "lockres %.*s, EX Holders %u\n",
+ lockres->l_namelen, lockres->l_name,
+ lockres->l_ex_holders);
+ goto drop_ref;
+ }
+
+ /* yay, we can downconvert now. */
+ new_level = user_highest_compat_lock_level(lockres->l_blocking);
+ lockres->l_requested = new_level;
+ lockres->l_flags |= USER_LOCK_BUSY;
+ mlog(ML_BASTS, "lockres %.*s, downconvert %d => %d\n",
+ lockres->l_namelen, lockres->l_name, lockres->l_level, new_level);
+ spin_unlock(&lockres->l_lock);
+
+ /* need lock downconvert request now... */
+ status = ocfs2_dlm_lock(conn, new_level, &lockres->l_lksb,
+ DLM_LKF_CONVERT|DLM_LKF_VALBLK,
+ lockres->l_name,
+ lockres->l_namelen);
+ if (status) {
+ user_log_dlm_error("ocfs2_dlm_lock", status, lockres);
+ user_recover_from_dlm_error(lockres);
+ }
+
+drop_ref:
+ user_dlm_drop_inode_ref(lockres);
+}
+
+static inline void user_dlm_inc_holders(struct user_lock_res *lockres,
+ int level)
+{
+ switch(level) {
+ case DLM_LOCK_EX:
+ lockres->l_ex_holders++;
+ break;
+ case DLM_LOCK_PR:
+ lockres->l_ro_holders++;
+ break;
+ default:
+ BUG();
+ }
+}
+
+/* predict what lock level we'll be dropping down to on behalf
+ * of another node, and return true if the currently wanted
+ * level will be compatible with it. */
+static inline int
+user_may_continue_on_blocked_lock(struct user_lock_res *lockres,
+ int wanted)
+{
+ BUG_ON(!(lockres->l_flags & USER_LOCK_BLOCKED));
+
+ return wanted <= user_highest_compat_lock_level(lockres->l_blocking);
+}
+
+int user_dlm_cluster_lock(struct user_lock_res *lockres,
+ int level,
+ int lkm_flags)
+{
+ int status, local_flags;
+ struct ocfs2_cluster_connection *conn =
+ cluster_connection_from_user_lockres(lockres);
+
+ if (level != DLM_LOCK_EX &&
+ level != DLM_LOCK_PR) {
+ mlog(ML_ERROR, "lockres %.*s: invalid request!\n",
+ lockres->l_namelen, lockres->l_name);
+ status = -EINVAL;
+ goto bail;
+ }
+
+ mlog(ML_BASTS, "lockres %.*s, level %d, flags = 0x%x\n",
+ lockres->l_namelen, lockres->l_name, level, lkm_flags);
+
+again:
+ if (signal_pending(current)) {
+ status = -ERESTARTSYS;
+ goto bail;
+ }
+
+ spin_lock(&lockres->l_lock);
+ if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
+ spin_unlock(&lockres->l_lock);
+ status = -EAGAIN;
+ goto bail;
+ }
+
+ /* We only compare against the currently granted level
+ * here. If the lock is blocked waiting on a downconvert,
+ * we'll get caught below. */
+ if ((lockres->l_flags & USER_LOCK_BUSY) &&
+ (level > lockres->l_level)) {
+ /* is someone sitting in dlm_lock? If so, wait on
+ * them. */
+ spin_unlock(&lockres->l_lock);
+
+ user_wait_on_busy_lock(lockres);
+ goto again;
+ }
+
+ if ((lockres->l_flags & USER_LOCK_BLOCKED) &&
+ (!user_may_continue_on_blocked_lock(lockres, level))) {
+ /* is the lock is currently blocked on behalf of
+ * another node */
+ spin_unlock(&lockres->l_lock);
+
+ user_wait_on_blocked_lock(lockres);
+ goto again;
+ }
+
+ if (level > lockres->l_level) {
+ local_flags = lkm_flags | DLM_LKF_VALBLK;
+ if (lockres->l_level != DLM_LOCK_IV)
+ local_flags |= DLM_LKF_CONVERT;
+
+ lockres->l_requested = level;
+ lockres->l_flags |= USER_LOCK_BUSY;
+ spin_unlock(&lockres->l_lock);
+
+ BUG_ON(level == DLM_LOCK_IV);
+ BUG_ON(level == DLM_LOCK_NL);
+
+ /* call dlm_lock to upgrade lock now */
+ status = ocfs2_dlm_lock(conn, level, &lockres->l_lksb,
+ local_flags, lockres->l_name,
+ lockres->l_namelen);
+ if (status) {
+ if ((lkm_flags & DLM_LKF_NOQUEUE) &&
+ (status != -EAGAIN))
+ user_log_dlm_error("ocfs2_dlm_lock",
+ status, lockres);
+ user_recover_from_dlm_error(lockres);
+ goto bail;
+ }
+
+ user_wait_on_busy_lock(lockres);
+ goto again;
+ }
+
+ user_dlm_inc_holders(lockres, level);
+ spin_unlock(&lockres->l_lock);
+
+ status = 0;
+bail:
+ return status;
+}
+
+static inline void user_dlm_dec_holders(struct user_lock_res *lockres,
+ int level)
+{
+ switch(level) {
+ case DLM_LOCK_EX:
+ BUG_ON(!lockres->l_ex_holders);
+ lockres->l_ex_holders--;
+ break;
+ case DLM_LOCK_PR:
+ BUG_ON(!lockres->l_ro_holders);
+ lockres->l_ro_holders--;
+ break;
+ default:
+ BUG();
+ }
+}
+
+void user_dlm_cluster_unlock(struct user_lock_res *lockres,
+ int level)
+{
+ if (level != DLM_LOCK_EX &&
+ level != DLM_LOCK_PR) {
+ mlog(ML_ERROR, "lockres %.*s: invalid request!\n",
+ lockres->l_namelen, lockres->l_name);
+ return;
+ }
+
+ spin_lock(&lockres->l_lock);
+ user_dlm_dec_holders(lockres, level);
+ __user_dlm_cond_queue_lockres(lockres);
+ spin_unlock(&lockres->l_lock);
+}
+
+void user_dlm_write_lvb(struct inode *inode,
+ const char *val,
+ unsigned int len)
+{
+ struct user_lock_res *lockres = &DLMFS_I(inode)->ip_lockres;
+ char *lvb;
+
+ BUG_ON(len > DLM_LVB_LEN);
+
+ spin_lock(&lockres->l_lock);
+
+ BUG_ON(lockres->l_level < DLM_LOCK_EX);
+ lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
+ memcpy(lvb, val, len);
+
+ spin_unlock(&lockres->l_lock);
+}
+
+ssize_t user_dlm_read_lvb(struct inode *inode,
+ char *val,
+ unsigned int len)
+{
+ struct user_lock_res *lockres = &DLMFS_I(inode)->ip_lockres;
+ char *lvb;
+ ssize_t ret = len;
+
+ BUG_ON(len > DLM_LVB_LEN);
+
+ spin_lock(&lockres->l_lock);
+
+ BUG_ON(lockres->l_level < DLM_LOCK_PR);
+ if (ocfs2_dlm_lvb_valid(&lockres->l_lksb)) {
+ lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
+ memcpy(val, lvb, len);
+ } else
+ ret = 0;
+
+ spin_unlock(&lockres->l_lock);
+ return ret;
+}
+
+void user_dlm_lock_res_init(struct user_lock_res *lockres,
+ struct dentry *dentry)
+{
+ memset(lockres, 0, sizeof(*lockres));
+
+ spin_lock_init(&lockres->l_lock);
+ init_waitqueue_head(&lockres->l_event);
+ lockres->l_level = DLM_LOCK_IV;
+ lockres->l_requested = DLM_LOCK_IV;
+ lockres->l_blocking = DLM_LOCK_IV;
+
+ /* should have been checked before getting here. */
+ BUG_ON(dentry->d_name.len >= USER_DLM_LOCK_ID_MAX_LEN);
+
+ memcpy(lockres->l_name,
+ dentry->d_name.name,
+ dentry->d_name.len);
+ lockres->l_namelen = dentry->d_name.len;
+}
+
+int user_dlm_destroy_lock(struct user_lock_res *lockres)
+{
+ int status = -EBUSY;
+ struct ocfs2_cluster_connection *conn =
+ cluster_connection_from_user_lockres(lockres);
+
+ mlog(ML_BASTS, "lockres %.*s\n", lockres->l_namelen, lockres->l_name);
+
+ spin_lock(&lockres->l_lock);
+ if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
+ spin_unlock(&lockres->l_lock);
+ goto bail;
+ }
+
+ lockres->l_flags |= USER_LOCK_IN_TEARDOWN;
+
+ while (lockres->l_flags & USER_LOCK_BUSY) {
+ spin_unlock(&lockres->l_lock);
+
+ user_wait_on_busy_lock(lockres);
+
+ spin_lock(&lockres->l_lock);
+ }
+
+ if (lockres->l_ro_holders || lockres->l_ex_holders) {
+ lockres->l_flags &= ~USER_LOCK_IN_TEARDOWN;
+ spin_unlock(&lockres->l_lock);
+ goto bail;
+ }
+
+ status = 0;
+ if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
+ /*
+ * lock is never requested, leave USER_LOCK_IN_TEARDOWN set
+ * to avoid new lock request coming in.
+ */
+ spin_unlock(&lockres->l_lock);
+ goto bail;
+ }
+
+ lockres->l_flags &= ~USER_LOCK_ATTACHED;
+ lockres->l_flags |= USER_LOCK_BUSY;
+ spin_unlock(&lockres->l_lock);
+
+ status = ocfs2_dlm_unlock(conn, &lockres->l_lksb, DLM_LKF_VALBLK);
+ if (status) {
+ spin_lock(&lockres->l_lock);
+ lockres->l_flags &= ~USER_LOCK_IN_TEARDOWN;
+ lockres->l_flags &= ~USER_LOCK_BUSY;
+ spin_unlock(&lockres->l_lock);
+ user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
+ goto bail;
+ }
+
+ user_wait_on_busy_lock(lockres);
+
+ status = 0;
+bail:
+ return status;
+}
+
+static void user_dlm_recovery_handler_noop(int node_num,
+ void *recovery_data)
+{
+ /* We ignore recovery events */
+ return;
+}
+
+void user_dlm_set_locking_protocol(void)
+{
+ ocfs2_stack_glue_set_max_proto_version(&user_dlm_lproto.lp_max_version);
+}
+
+struct ocfs2_cluster_connection *user_dlm_register(const struct qstr *name)
+{
+ int rc;
+ struct ocfs2_cluster_connection *conn;
+
+ rc = ocfs2_cluster_connect_agnostic(name->name, name->len,
+ &user_dlm_lproto,
+ user_dlm_recovery_handler_noop,
+ NULL, &conn);
+ if (rc)
+ mlog_errno(rc);
+
+ return rc ? ERR_PTR(rc) : conn;
+}
+
+void user_dlm_unregister(struct ocfs2_cluster_connection *conn)
+{
+ ocfs2_cluster_disconnect(conn, 0);
+}
diff --git a/fs/ocfs2/dlmfs/userdlm.h b/fs/ocfs2/dlmfs/userdlm.h
new file mode 100644
index 000000000..ede94a6e7
--- /dev/null
+++ b/fs/ocfs2/dlmfs/userdlm.h
@@ -0,0 +1,113 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * userdlm.h
+ *
+ * Userspace dlm defines
+ *
+ * Copyright (C) 2002, 2004 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+
+#ifndef USERDLM_H
+#define USERDLM_H
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+/* user_lock_res->l_flags flags. */
+#define USER_LOCK_ATTACHED (0x00000001) /* we have initialized
+ * the lvb */
+#define USER_LOCK_BUSY (0x00000002) /* we are currently in
+ * dlm_lock */
+#define USER_LOCK_BLOCKED (0x00000004) /* blocked waiting to
+ * downconvert*/
+#define USER_LOCK_IN_TEARDOWN (0x00000008) /* we're currently
+ * destroying this
+ * lock. */
+#define USER_LOCK_QUEUED (0x00000010) /* lock is on the
+ * workqueue */
+#define USER_LOCK_IN_CANCEL (0x00000020)
+
+struct user_lock_res {
+ spinlock_t l_lock;
+
+ int l_flags;
+
+#define USER_DLM_LOCK_ID_MAX_LEN 32
+ char l_name[USER_DLM_LOCK_ID_MAX_LEN];
+ int l_namelen;
+ int l_level;
+ unsigned int l_ro_holders;
+ unsigned int l_ex_holders;
+ struct ocfs2_dlm_lksb l_lksb;
+
+ int l_requested;
+ int l_blocking;
+
+ wait_queue_head_t l_event;
+
+ struct work_struct l_work;
+};
+
+extern struct workqueue_struct *user_dlm_worker;
+
+void user_dlm_lock_res_init(struct user_lock_res *lockres,
+ struct dentry *dentry);
+int user_dlm_destroy_lock(struct user_lock_res *lockres);
+int user_dlm_cluster_lock(struct user_lock_res *lockres,
+ int level,
+ int lkm_flags);
+void user_dlm_cluster_unlock(struct user_lock_res *lockres,
+ int level);
+void user_dlm_write_lvb(struct inode *inode,
+ const char *val,
+ unsigned int len);
+ssize_t user_dlm_read_lvb(struct inode *inode,
+ char *val,
+ unsigned int len);
+struct ocfs2_cluster_connection *user_dlm_register(const struct qstr *name);
+void user_dlm_unregister(struct ocfs2_cluster_connection *conn);
+void user_dlm_set_locking_protocol(void);
+
+struct dlmfs_inode_private {
+ struct ocfs2_cluster_connection *ip_conn;
+
+ struct user_lock_res ip_lockres; /* unused for directories. */
+ struct inode *ip_parent;
+
+ struct inode ip_vfs_inode;
+};
+
+static inline struct dlmfs_inode_private *
+DLMFS_I(struct inode *inode)
+{
+ return container_of(inode,
+ struct dlmfs_inode_private,
+ ip_vfs_inode);
+}
+
+struct dlmfs_filp_private {
+ int fp_lock_level;
+};
+
+#define DLMFS_MAGIC 0x76a9f425
+
+#endif /* USERDLM_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 00:05:29 +0000