smb3: cleanup and clarify status of tree connections

Currently the way the tid (tree connection) status is tracked
is confusing.  The same enum is used for structs cifs_tcon
and cifs_ses and TCP_Server_info, but each of these three has
different states that they transition among.  The current
code also unnecessarily uses camelCase.

Convert from use of statusEnum to a new tid_status_enum for
tree connections.  The valid states for a tid are:

        TID_NEW = 0,
        TID_GOOD,
        TID_EXITING,
        TID_NEED_RECON,
        TID_NEED_TCON,
        TID_IN_TCON,
        TID_NEED_FILES_INVALIDATE, /* unused, considering removing in future */
        TID_IN_FILES_INVALIDATE

It also removes CifsNeedTcon, CifsInTcon, CifsNeedFilesInvalidate and
CifsInFilesInvalidate from the statusEnum used for session and
TCP_Server_Info since they are not relevant for those.

A follow on patch will fix the places where we use the
tcon->need_reconnect flag to be more consistent with the tid->status.

Also fixes a bug that was:
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index ad3cd6053f4e..cd9127510a55 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -115,10 +115,18 @@ enum statusEnum {
 	CifsInNegotiate,
 	CifsNeedSessSetup,
 	CifsInSessSetup,
-	CifsNeedTcon,
-	CifsInTcon,
-	CifsNeedFilesInvalidate,
-	CifsInFilesInvalidate
+};
+
+/* associated with each tree connection to the server */
+enum tid_status_enum {
+	TID_NEW = 0,
+	TID_GOOD,
+	TID_EXITING,
+	TID_NEED_RECON,
+	TID_NEED_TCON,
+	TID_IN_TCON,
+	TID_NEED_FILES_INVALIDATE, /* currently unused */
+	TID_IN_FILES_INVALIDATE
 };
 
 enum securityEnum {
@@ -1032,7 +1040,7 @@ struct cifs_tcon {
 	char *password;		/* for share-level security */
 	__u32 tid;		/* The 4 byte tree id */
 	__u16 Flags;		/* optional support bits */
-	enum statusEnum tidStatus;
+	enum tid_status_enum status;
 	atomic_t num_smbs_sent;
 	union {
 		struct {