afs: Add metadata xattrs

Add xattrs to allow the user to get/set metadata in lieu of having pioctl()
available.  The following xattrs are now available:

 - "afs.cell"

   The name of the cell in which the vnode's volume resides.

 - "afs.fid"

   The volume ID, vnode ID and vnode uniquifier of the file as three hex
   numbers separated by colons.

 - "afs.volume"

   The name of the volume in which the vnode resides.

For example:

	# getfattr -d -m ".*" /mnt/scratch
	getfattr: Removing leading '/' from absolute path names
	# file: mnt/scratch
	afs.cell="mycell.myorg.org"
	afs.fid="10000b:1:1"
	afs.volume="scratch"

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index aae55dd15108..342316a9e3e0 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -28,6 +28,11 @@ struct afs_iget_data {
 	struct afs_volume	*volume;	/* volume on which resides */
 };
 
+static const struct inode_operations afs_symlink_inode_operations = {
+	.get_link	= page_get_link,
+	.listxattr	= afs_listxattr,
+};
+
 /*
  * map the AFS file status to the inode member variables
  */
@@ -67,7 +72,7 @@ static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
 			inode->i_fop	= &afs_mntpt_file_operations;
 		} else {
 			inode->i_mode	= S_IFLNK | vnode->status.mode;
-			inode->i_op	= &page_symlink_inode_operations;
+			inode->i_op	= &afs_symlink_inode_operations;
 		}
 		inode_nohighmem(inode);
 		break;