cifs: reinstate sharing of tree connections
Use a similar approach to the SMB session sharing. Add a list of tcons
attached to each SMB session. Move the refcount to non-atomic. Protect
all of the above with the cifs_tcp_ses_lock. Add functions to
properly find and put references to the tcons.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 631a99f..f1ae1f5 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -233,16 +233,15 @@
* session
*/
struct cifsTconInfo {
- struct list_head cifsConnectionList;
+ struct list_head tcon_list;
+ int tc_count;
struct list_head openFileList;
- struct semaphore tconSem;
struct cifsSesInfo *ses; /* pointer to session associated with */
char treeName[MAX_TREE_SIZE + 1]; /* UNC name of resource in ASCII */
char *nativeFileSystem;
__u16 tid; /* The 2 byte tree id */
__u16 Flags; /* optional support bits */
enum statusEnum tidStatus;
- atomic_t useCount; /* how many explicit/implicit mounts to share */
#ifdef CONFIG_CIFS_STATS
atomic_t num_smbs_sent;
atomic_t num_writes;
@@ -600,9 +599,13 @@
*/
GLOBAL_EXTERN struct list_head cifs_tcp_ses_list;
-/* protects cifs_tcp_ses_list and srv_count for each tcp session */
+/*
+ * This lock protects the cifs_tcp_ses_list, the list of smb sessions per
+ * tcp session, and the list of tcon's per smb session. It also protects
+ * the reference counters for the server, smb session, and tcon. Finally,
+ * changes to the tcon->tidStatus should be done while holding this lock.
+ */
GLOBAL_EXTERN rwlock_t cifs_tcp_ses_lock;
-GLOBAL_EXTERN struct list_head GlobalTreeConnectionList; /* BB to be removed */
GLOBAL_EXTERN rwlock_t GlobalSMBSeslock; /* protects list inserts on 3 above */
GLOBAL_EXTERN struct list_head GlobalOplock_Q;