Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 244 insertions, 0 deletions

diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
new file mode 100644
index 000000000..b601610e9
--- /dev/null
+++ b/fs/configfs/inode.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * inode.c - basic inode and dentry operations.
+ *
+ * Based on sysfs:
+ * 	sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
+ *
+ * configfs Copyright (C) 2005 Oracle.  All rights reserved.
+ *
+ * Please see Documentation/filesystems/configfs.rst for more
+ * information.
+ */
+
+#undef DEBUG
+
+#include <linux/pagemap.h>
+#include <linux/namei.h>
+#include <linux/backing-dev.h>
+#include <linux/capability.h>
+#include <linux/sched.h>
+#include <linux/lockdep.h>
+#include <linux/slab.h>
+
+#include <linux/configfs.h>
+#include "configfs_internal.h"
+
+#ifdef CONFIG_LOCKDEP
+static struct lock_class_key default_group_class[MAX_LOCK_DEPTH];
+#endif
+
+static const struct inode_operations configfs_inode_operations ={
+	.setattr	= configfs_setattr,
+};
+
+int configfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+		     struct iattr *iattr)
+{
+	struct inode * inode = d_inode(dentry);
+	struct configfs_dirent * sd = dentry->d_fsdata;
+	struct iattr * sd_iattr;
+	unsigned int ia_valid = iattr->ia_valid;
+	int error;
+
+	if (!sd)
+		return -EINVAL;
+
+	sd_iattr = sd->s_iattr;
+	if (!sd_iattr) {
+		/* setting attributes for the first time, allocate now */
+		sd_iattr = kzalloc(sizeof(struct iattr), GFP_KERNEL);
+		if (!sd_iattr)
+			return -ENOMEM;
+		/* assign default attributes */
+		sd_iattr->ia_mode = sd->s_mode;
+		sd_iattr->ia_uid = GLOBAL_ROOT_UID;
+		sd_iattr->ia_gid = GLOBAL_ROOT_GID;
+		sd_iattr->ia_atime = sd_iattr->ia_mtime =
+			sd_iattr->ia_ctime = current_time(inode);
+		sd->s_iattr = sd_iattr;
+	}
+	/* attributes were changed atleast once in past */
+
+	error = simple_setattr(mnt_userns, dentry, iattr);
+	if (error)
+		return error;
+
+	if (ia_valid & ATTR_UID)
+		sd_iattr->ia_uid = iattr->ia_uid;
+	if (ia_valid & ATTR_GID)
+		sd_iattr->ia_gid = iattr->ia_gid;
+	if (ia_valid & ATTR_ATIME)
+		sd_iattr->ia_atime = iattr->ia_atime;
+	if (ia_valid & ATTR_MTIME)
+		sd_iattr->ia_mtime = iattr->ia_mtime;
+	if (ia_valid & ATTR_CTIME)
+		sd_iattr->ia_ctime = iattr->ia_ctime;
+	if (ia_valid & ATTR_MODE) {
+		umode_t mode = iattr->ia_mode;
+
+		if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+			mode &= ~S_ISGID;
+		sd_iattr->ia_mode = sd->s_mode = mode;
+	}
+
+	return error;
+}
+
+static inline void set_default_inode_attr(struct inode * inode, umode_t mode)
+{
+	inode->i_mode = mode;
+	inode->i_atime = inode->i_mtime =
+		inode->i_ctime = current_time(inode);
+}
+
+static inline void set_inode_attr(struct inode * inode, struct iattr * iattr)
+{
+	inode->i_mode = iattr->ia_mode;
+	inode->i_uid = iattr->ia_uid;
+	inode->i_gid = iattr->ia_gid;
+	inode->i_atime = iattr->ia_atime;
+	inode->i_mtime = iattr->ia_mtime;
+	inode->i_ctime = iattr->ia_ctime;
+}
+
+struct inode *configfs_new_inode(umode_t mode, struct configfs_dirent *sd,
+				 struct super_block *s)
+{
+	struct inode * inode = new_inode(s);
+	if (inode) {
+		inode->i_ino = get_next_ino();
+		inode->i_mapping->a_ops = &ram_aops;
+		inode->i_op = &configfs_inode_operations;
+
+		if (sd->s_iattr) {
+			/* sysfs_dirent has non-default attributes
+			 * get them for the new inode from persistent copy
+			 * in sysfs_dirent
+			 */
+			set_inode_attr(inode, sd->s_iattr);
+		} else
+			set_default_inode_attr(inode, mode);
+	}
+	return inode;
+}
+
+#ifdef CONFIG_LOCKDEP
+
+static void configfs_set_inode_lock_class(struct configfs_dirent *sd,
+					  struct inode *inode)
+{
+	int depth = sd->s_depth;
+
+	if (depth > 0) {
+		if (depth <= ARRAY_SIZE(default_group_class)) {
+			lockdep_set_class(&inode->i_rwsem,
+					  &default_group_class[depth - 1]);
+		} else {
+			/*
+			 * In practice the maximum level of locking depth is
+			 * already reached. Just inform about possible reasons.
+			 */
+			pr_info("Too many levels of inodes for the locking correctness validator.\n");
+			pr_info("Spurious warnings may appear.\n");
+		}
+	}
+}
+
+#else /* CONFIG_LOCKDEP */
+
+static void configfs_set_inode_lock_class(struct configfs_dirent *sd,
+					  struct inode *inode)
+{
+}
+
+#endif /* CONFIG_LOCKDEP */
+
+struct inode *configfs_create(struct dentry *dentry, umode_t mode)
+{
+	struct inode *inode = NULL;
+	struct configfs_dirent *sd;
+	struct inode *p_inode;
+
+	if (!dentry)
+		return ERR_PTR(-ENOENT);
+
+	if (d_really_is_positive(dentry))
+		return ERR_PTR(-EEXIST);
+
+	sd = dentry->d_fsdata;
+	inode = configfs_new_inode(mode, sd, dentry->d_sb);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	p_inode = d_inode(dentry->d_parent);
+	p_inode->i_mtime = p_inode->i_ctime = current_time(p_inode);
+	configfs_set_inode_lock_class(sd, inode);
+	return inode;
+}
+
+/*
+ * Get the name for corresponding element represented by the given configfs_dirent
+ */
+const unsigned char * configfs_get_name(struct configfs_dirent *sd)
+{
+	struct configfs_attribute *attr;
+
+	BUG_ON(!sd || !sd->s_element);
+
+	/* These always have a dentry, so use that */
+	if (sd->s_type & (CONFIGFS_DIR | CONFIGFS_ITEM_LINK))
+		return sd->s_dentry->d_name.name;
+
+	if (sd->s_type & (CONFIGFS_ITEM_ATTR | CONFIGFS_ITEM_BIN_ATTR)) {
+		attr = sd->s_element;
+		return attr->ca_name;
+	}
+	return NULL;
+}
+
+
+/*
+ * Unhashes the dentry corresponding to given configfs_dirent
+ * Called with parent inode's i_mutex held.
+ */
+void configfs_drop_dentry(struct configfs_dirent * sd, struct dentry * parent)
+{
+	struct dentry * dentry = sd->s_dentry;
+
+	if (dentry) {
+		spin_lock(&dentry->d_lock);
+		if (simple_positive(dentry)) {
+			dget_dlock(dentry);
+			__d_drop(dentry);
+			spin_unlock(&dentry->d_lock);
+			simple_unlink(d_inode(parent), dentry);
+		} else
+			spin_unlock(&dentry->d_lock);
+	}
+}
+
+void configfs_hash_and_remove(struct dentry * dir, const char * name)
+{
+	struct configfs_dirent * sd;
+	struct configfs_dirent * parent_sd = dir->d_fsdata;
+
+	if (d_really_is_negative(dir))
+		/* no inode means this hasn't been made visible yet */
+		return;
+
+	inode_lock(d_inode(dir));
+	list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
+		if (!sd->s_element)
+			continue;
+		if (!strcmp(configfs_get_name(sd), name)) {
+			spin_lock(&configfs_dirent_lock);
+			list_del_init(&sd->s_sibling);
+			spin_unlock(&configfs_dirent_lock);
+			configfs_drop_dentry(sd, dir);
+			configfs_put(sd);
+			break;
+		}
+	}
+	inode_unlock(d_inode(dir));
+}