cifs: convert tcpSem to a mutex

Mutexes are preferred for single-holder semaphores...
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifsglob.h

@@ -151,7 +151,7 @@ struct TCP_Server_Info {
 	atomic_t num_waiters;   /* blocked waiting to get in sendrecv */
 #endif
 	enum statusEnum tcpStatus; /* what we think the status is */
-	struct semaphore tcpSem;
+	struct mutex srv_mutex;
 	struct task_struct *tsk;
 	char server_GUID[16];
 	char secMode;

fs/cifs/connect.c

@@ -156,7 +156,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 	}
 	read_unlock(&cifs_tcp_ses_lock);
 	/* do not want to be sending data on a socket we are freeing */
-	down(&server->tcpSem);
+	mutex_lock(&server->srv_mutex);
 	if (server->ssocket) {
 		cFYI(1, ("State: 0x%x Flags: 0x%lx", server->ssocket->state,
 			server->ssocket->flags));
@@ -182,7 +182,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 		}
 	}
 	spin_unlock(&GlobalMid_Lock);
-	up(&server->tcpSem);
+	mutex_unlock(&server->srv_mutex);
 
 	while ((server->tcpStatus != CifsExiting) &&
 	       (server->tcpStatus != CifsGood)) {
@@ -2175,7 +2175,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 			to the struct since the kernel thread not created yet
 			so no need to spinlock this init of tcpStatus */
 			srvTcp->tcpStatus = CifsNew;
-			init_MUTEX(&srvTcp->tcpSem);
+			mutex_init(&srvTcp->srv_mutex);
 
 			/*
 			 * since we're in a cifs function already, we know that

fs/cifs/transport.c

@@ -516,11 +516,11 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
 	   and avoid races inside tcp sendmsg code that could cause corruption
 	   of smb data */
 
-	down(&ses->server->tcpSem);
+	mutex_lock(&ses->server->srv_mutex);
 
 	rc = allocate_mid(ses, in_buf, &midQ);
 	if (rc) {
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		cifs_small_buf_release(in_buf);
 		/* Update # of requests on wire to server */
 		atomic_dec(&ses->server->inFlight);
@@ -541,7 +541,7 @@ SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
 	midQ->when_sent = jiffies;
 #endif
 
-	up(&ses->server->tcpSem);
+	mutex_unlock(&ses->server->srv_mutex);
 	cifs_small_buf_release(in_buf);
 
 	if (rc < 0)
@@ -698,11 +698,11 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 	   and avoid races inside tcp sendmsg code that could cause corruption
 	   of smb data */
 
-	down(&ses->server->tcpSem);
+	mutex_lock(&ses->server->srv_mutex);
 
 	rc = allocate_mid(ses, in_buf, &midQ);
 	if (rc) {
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		/* Update # of requests on wire to server */
 		atomic_dec(&ses->server->inFlight);
 		wake_up(&ses->server->request_q);
@@ -713,7 +713,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 		cERROR(1, ("Illegal length, greater than maximum frame, %d",
 			in_buf->smb_buf_length));
 		DeleteMidQEntry(midQ);
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		/* Update # of requests on wire to server */
 		atomic_dec(&ses->server->inFlight);
 		wake_up(&ses->server->request_q);
@@ -733,7 +733,7 @@ SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
 	atomic_dec(&ses->server->inSend);
 	midQ->when_sent = jiffies;
 #endif
-	up(&ses->server->tcpSem);
+	mutex_unlock(&ses->server->srv_mutex);
 
 	if (rc < 0)
 		goto out;
@@ -861,16 +861,16 @@ send_nt_cancel(struct cifsTconInfo *tcon, struct smb_hdr *in_buf,
 
 	header_assemble(in_buf, SMB_COM_NT_CANCEL, tcon, 0);
 	in_buf->Mid = mid;
-	down(&ses->server->tcpSem);
+	mutex_lock(&ses->server->srv_mutex);
 	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
 	if (rc) {
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		return rc;
 	}
 	rc = smb_send(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
 	      (struct sockaddr *) &(ses->server->addr.sockAddr),
 	      ses->server->noblocksnd);
-	up(&ses->server->tcpSem);
+	mutex_unlock(&ses->server->srv_mutex);
 	return rc;
 }
 
@@ -936,16 +936,16 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon,
 	   and avoid races inside tcp sendmsg code that could cause corruption
 	   of smb data */
 
-	down(&ses->server->tcpSem);
+	mutex_lock(&ses->server->srv_mutex);
 
 	rc = allocate_mid(ses, in_buf, &midQ);
 	if (rc) {
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		return rc;
 	}
 
 	if (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
-		up(&ses->server->tcpSem);
+		mutex_unlock(&ses->server->srv_mutex);
 		cERROR(1, ("Illegal length, greater than maximum frame, %d",
 			in_buf->smb_buf_length));
 		DeleteMidQEntry(midQ);
@@ -965,7 +965,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon,
 	atomic_dec(&ses->server->inSend);
 	midQ->when_sent = jiffies;
 #endif
-	up(&ses->server->tcpSem);
+	mutex_unlock(&ses->server->srv_mutex);
 
 	if (rc < 0) {
 		DeleteMidQEntry(midQ);