cifs: define superblock-level cache index objects and register them

Define superblock-level cache index objects (managed by cifsTconInfo structs).
Each superblock object is created in a server-level index object and in itself
an index into which inode-level objects are inserted.

The superblock object is keyed by sharename. The UniqueId/IndexNumber is used to
validate that the exported share is the same since we accessed it last time.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c
index ea97b76f8aa6..eba9beb94a4c 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -39,3 +39,20 @@ void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server)
         server->fscache = NULL;
 }
 
+void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon)
+{
+        struct TCP_Server_Info *server = tcon->ses->server;
+
+        tcon->fscache =
+                fscache_acquire_cookie(server->fscache,
+                                &cifs_fscache_super_index_def, tcon);
+        cFYI(1, "CIFS: get superblock cookie (0x%p/0x%p)",
+                                server->fscache, tcon->fscache);
+}
+
+void cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon)
+{
+        cFYI(1, "CIFS: releasing superblock cookie (0x%p)", tcon->fscache);
+        fscache_relinquish_cookie(tcon->fscache, 0);
+        tcon->fscache = NULL;
+}