cifs: check only tcon status on tcon related functions

We had a couple of checks for session in cifs_tree_connect
and cifs_mark_open_files_invalid, which were unnecessary.
And that was done with ses_lock. Changed that to tc_lock too.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/connect.c

@@ -4036,9 +4036,13 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru
 
 	/* only send once per connect */
 	spin_lock(&tcon->tc_lock);
-	if (tcon->ses->ses_status != SES_GOOD ||
-	    (tcon->status != TID_NEW &&
-	    tcon->status != TID_NEED_TCON)) {
+	if (tcon->status != TID_NEW &&
+	    tcon->status != TID_NEED_TCON) {
+		spin_unlock(&tcon->tc_lock);
+		return -EHOSTDOWN;
+	}
+
+	if (tcon->status == TID_GOOD) {
 		spin_unlock(&tcon->tc_lock);
 		return 0;
 	}

fs/cifs/dfs.c

@@ -502,9 +502,13 @@ int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const stru
 
 	/* only send once per connect */
 	spin_lock(&tcon->tc_lock);
-	if (tcon->ses->ses_status != SES_GOOD ||
-	    (tcon->status != TID_NEW &&
-	    tcon->status != TID_NEED_TCON)) {
+	if (tcon->status != TID_NEW &&
+	    tcon->status != TID_NEED_TCON) {
+		spin_unlock(&tcon->tc_lock);
+		return -EHOSTDOWN;
+	}
+
+	if (tcon->status == TID_GOOD) {
 		spin_unlock(&tcon->tc_lock);
 		return 0;
 	}

fs/cifs/dfs_cache.c

@@ -1191,7 +1191,7 @@ static int __refresh_tcon(const char *path, struct cifs_tcon *tcon, bool force_r
 	}
 
 	spin_lock(&ipc->tc_lock);
-	if (ses->ses_status != SES_GOOD || ipc->status != TID_GOOD) {
+	if (ipc->status != TID_GOOD) {
 		spin_unlock(&ipc->tc_lock);
 		cifs_dbg(FYI, "%s: skip cache refresh due to disconnected ipc\n", __func__);
 		goto out;

fs/cifs/file.c

@@ -174,13 +174,13 @@ cifs_mark_open_files_invalid(struct cifs_tcon *tcon)
 	struct list_head *tmp1;
 
 	/* only send once per connect */
-	spin_lock(&tcon->ses->ses_lock);
-	if ((tcon->ses->ses_status != SES_GOOD) || (tcon->status != TID_NEED_RECON)) {
-		spin_unlock(&tcon->ses->ses_lock);
+	spin_lock(&tcon->tc_lock);
+	if (tcon->status != TID_NEED_RECON) {
+		spin_unlock(&tcon->tc_lock);
 		return;
 	}
 	tcon->status = TID_IN_FILES_INVALIDATE;
-	spin_unlock(&tcon->ses->ses_lock);
+	spin_unlock(&tcon->tc_lock);
 
 	/* list all files open on tree connection and mark them invalid */
 	spin_lock(&tcon->open_file_lock);