cleancache: zap uuid arg of cleancache_init_shared_fs

Use super_block->s_uuid instead.  Every shared filesystem using cleancache
must now initialize super_block->s_uuid before calling
cleancache_init_shared_fs.  The only one on the tree, ocfs2, already meets
this requirement.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Stefan Hengelein <ilendir@googlemail.com>
Cc: Florian Schmaus <fschmaus@gmail.com>
Cc: Andor Daam <andor.daam@googlemail.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/cleancache.c b/mm/cleancache.c
index 053bcd8..532495f 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -155,7 +155,7 @@
 EXPORT_SYMBOL(__cleancache_init_fs);
 
 /* Called by a cleancache-enabled clustered filesystem at time of mount */
-void __cleancache_init_shared_fs(char *uuid, struct super_block *sb)
+void __cleancache_init_shared_fs(struct super_block *sb)
 {
 	int i;
 
@@ -163,10 +163,10 @@
 	for (i = 0; i < MAX_INITIALIZABLE_FS; i++) {
 		if (shared_fs_poolid_map[i] == FS_UNKNOWN) {
 			sb->cleancache_poolid = i + FAKE_SHARED_FS_POOLID_OFFSET;
-			uuids[i] = uuid;
+			uuids[i] = sb->s_uuid;
 			if (cleancache_ops)
 				shared_fs_poolid_map[i] = cleancache_ops->init_shared_fs
-						(uuid, PAGE_SIZE);
+						(sb->s_uuid, PAGE_SIZE);
 			else
 				shared_fs_poolid_map[i] = FS_NO_BACKEND;
 			break;