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Commit cfc94cdf authored by Jan Kara's avatar Jan Kara Committed by Greg Kroah-Hartman
Browse files

debugfs: add rename for debugfs files 



Implement debugfs_rename() to allow renaming files/directories in debugfs.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 46336009

fs/debugfs/inode.c

+63 −0
Original line number Diff line number Diff line
@@ -368,6 +368,69 @@ void debugfs_remove(struct dentry *dentry) 
}

EXPORT_SYMBOL_GPL(debugfs_remove);



/**

 * debugfs_rename - rename a file/directory in the debugfs filesystem

 * @old_dir: a pointer to the parent dentry for the renamed object. This

 *          should be a directory dentry.

 * @old_dentry: dentry of an object to be renamed.

 * @new_dir: a pointer to the parent dentry where the object should be

 *          moved. This should be a directory dentry.

 * @new_name: a pointer to a string containing the target name.

 *

 * This function renames a file/directory in debugfs.  The target must not

 * exist for rename to succeed.

 *

 * This function will return a pointer to old_dentry (which is updated to

 * reflect renaming) if it succeeds. If an error occurs, %NULL will be

 * returned.

 *

 * If debugfs is not enabled in the kernel, the value -%ENODEV will be

 * returned.

 */

struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,

		struct dentry *new_dir, const char *new_name)

{

	int error;

	struct dentry *dentry = NULL, *trap;

	const char *old_name;



	trap = lock_rename(new_dir, old_dir);

	/* Source or destination directories don't exist? */

	if (!old_dir->d_inode || !new_dir->d_inode)

		goto exit;

	/* Source does not exist, cyclic rename, or mountpoint? */

	if (!old_dentry->d_inode || old_dentry == trap ||

	    d_mountpoint(old_dentry))

		goto exit;

	dentry = lookup_one_len(new_name, new_dir, strlen(new_name));

	/* Lookup failed, cyclic rename or target exists? */

	if (IS_ERR(dentry) || dentry == trap || dentry->d_inode)

		goto exit;



	old_name = fsnotify_oldname_init(old_dentry->d_name.name);



	error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode,

		dentry);

	if (error) {

		fsnotify_oldname_free(old_name);

		goto exit;

	}

	d_move(old_dentry, dentry);

	fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name,

		old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode),

		NULL, old_dentry->d_inode);

	fsnotify_oldname_free(old_name);

	unlock_rename(new_dir, old_dir);

	dput(dentry);

	return old_dentry;

exit:

	if (dentry && !IS_ERR(dentry))

		dput(dentry);

	unlock_rename(new_dir, old_dir);

	return NULL;

}

EXPORT_SYMBOL_GPL(debugfs_rename);



static decl_subsys(debug, NULL, NULL);



static int __init debugfs_init(void)

include/linux/debugfs.h

+9 −0
Original line number Diff line number Diff line
@@ -38,6 +38,9 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, 


void debugfs_remove(struct dentry *dentry);



struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,

                struct dentry *new_dir, const char *new_name);



struct dentry *debugfs_create_u8(const char *name, mode_t mode,

				 struct dentry *parent, u8 *value);

struct dentry *debugfs_create_u16(const char *name, mode_t mode,
@@ -85,6 +88,12 @@ static inline struct dentry *debugfs_create_symlink(const char *name, 
static inline void debugfs_remove(struct dentry *dentry)

{ }



static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,

                struct dentry *new_dir, char *new_name)

{

	return ERR_PTR(-ENODEV);

}



static inline struct dentry *debugfs_create_u8(const char *name, mode_t mode,

					       struct dentry *parent,

					       u8 *value)