1 files changed, 43 insertions, 35 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 0cc9584..310918b 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -254,44 +254,60 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
 	return smb_sendv(server, &iov, 1);
 }
 
-static int wait_for_free_request(struct TCP_Server_Info *server,
-				 const int long_op)
+static int
+wait_for_free_credits(struct TCP_Server_Info *server, const int optype,
+		      int *credits)
 {
-	if (long_op == CIFS_ASYNC_OP) {
+	int rc;
+
+	spin_lock(&server->req_lock);
+	if (optype == CIFS_ASYNC_OP) {
 		/* oplock breaks must not be held up */
-		atomic_inc(&server->inFlight);
+		server->in_flight++;
+		*credits -= 1;
+		spin_unlock(&server->req_lock);
 		return 0;
 	}
 
-	spin_lock(&GlobalMid_Lock);
 	while (1) {
-		if (atomic_read(&server->inFlight) >= cifs_max_pending) {
-			spin_unlock(&GlobalMid_Lock);
+		if (*credits <= 0) {
+			spin_unlock(&server->req_lock);
 			cifs_num_waiters_inc(server);
-			wait_event(server->request_q,
-				   atomic_read(&server->inFlight)
-				     < cifs_max_pending);
+			rc = wait_event_killable(server->request_q,
+						 has_credits(server, credits));
 			cifs_num_waiters_dec(server);
-			spin_lock(&GlobalMid_Lock);
+			if (rc)
+				return rc;
+			spin_lock(&server->req_lock);
 		} else {
 			if (server->tcpStatus == CifsExiting) {
-				spin_unlock(&GlobalMid_Lock);
+				spin_unlock(&server->req_lock);
 				return -ENOENT;
 			}
 
-			/* can not count locking commands against total
-			   as they are allowed to block on server */
+			/*
+			 * Can not count locking commands against total
+			 * as they are allowed to block on server.
+			 */
 
 			/* update # of requests on the wire to server */
-			if (long_op != CIFS_BLOCKING_OP)
-				atomic_inc(&server->inFlight);
-			spin_unlock(&GlobalMid_Lock);
+			if (optype != CIFS_BLOCKING_OP) {
+				*credits -= 1;
+				server->in_flight++;
+			}
+			spin_unlock(&server->req_lock);
 			break;
 		}
 	}
 	return 0;
 }
 
+static int
+wait_for_free_request(struct TCP_Server_Info *server, const int optype)
+{
+	return wait_for_free_credits(server, optype, get_credits_field(server));
+}
+
 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
 			struct mid_q_entry **ppmidQ)
 {
@@ -359,7 +375,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 	mid = AllocMidQEntry(hdr, server);
 	if (mid == NULL) {
 		mutex_unlock(&server->srv_mutex);
-		atomic_dec(&server->inFlight);
+		cifs_add_credits(server, 1);
 		wake_up(&server->request_q);
 		return -ENOMEM;
 	}
@@ -392,7 +408,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 	return rc;
 out_err:
 	delete_mid(mid);
-	atomic_dec(&server->inFlight);
+	cifs_add_credits(server, 1);
 	wake_up(&server->request_q);
 	return rc;
 }
@@ -564,8 +580,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 		mutex_unlock(&ses->server->srv_mutex);
 		cifs_small_buf_release(in_buf);
 		/* Update # of requests on wire to server */
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		cifs_add_credits(ses->server, 1);
 		return rc;
 	}
 	rc = cifs_sign_smb2(iov, n_vec, ses->server, &midQ->sequence_number);
@@ -601,8 +616,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
 			cifs_small_buf_release(in_buf);
-			atomic_dec(&ses->server->inFlight);
-			wake_up(&ses->server->request_q);
+			cifs_add_credits(ses->server, 1);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
@@ -612,8 +626,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		cifs_add_credits(ses->server, 1);
 		return rc;
 	}
 
@@ -637,8 +650,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 		midQ->resp_buf = NULL;
 out:
 	delete_mid(midQ);
-	atomic_dec(&ses->server->inFlight);
-	wake_up(&ses->server->request_q);
+	cifs_add_credits(ses->server, 1);
 
 	return rc;
 }
@@ -688,8 +700,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	if (rc) {
 		mutex_unlock(&ses->server->srv_mutex);
 		/* Update # of requests on wire to server */
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		cifs_add_credits(ses->server, 1);
 		return rc;
 	}
 
@@ -721,8 +732,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 			/* no longer considered to be "in-flight" */
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
-			atomic_dec(&ses->server->inFlight);
-			wake_up(&ses->server->request_q);
+			cifs_add_credits(ses->server, 1);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
@@ -730,8 +740,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		cifs_add_credits(ses->server, 1);
 		return rc;
 	}
 
@@ -747,8 +756,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	rc = cifs_check_receive(midQ, ses->server, 0);
 out:
 	delete_mid(midQ);
-	atomic_dec(&ses->server->inFlight);
-	wake_up(&ses->server->request_q);
+	cifs_add_credits(ses->server, 1);
 
 	return rc;
 }