CIFS: Simplify inFlight logic

by making it as unsigned integer and surround access with req_lock
from server structure.

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 23 insertions, 22 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 99a27cfa6cd2..e2673aa34381 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -254,28 +254,29 @@ 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_request(struct TCP_Server_Info *server, const int long_op)
 {
+        spin_lock(&server->req_lock);
+
         if (long_op == CIFS_ASYNC_OP) {
                 /* oplock breaks must not be held up */
-                atomic_inc(&server->inFlight);
+                server->in_flight++;
+                spin_unlock(&server->req_lock);
                 return 0;
         }
 
-        spin_lock(&GlobalMid_Lock);
         while (1) {
-                if (atomic_read(&server->inFlight) >= server->maxReq) {
-                        spin_unlock(&GlobalMid_Lock);
+                if (server->in_flight >= server->maxReq) {
+                        spin_unlock(&server->req_lock);
                         cifs_num_waiters_inc(server);
                         wait_event(server->request_q,
-                                   atomic_read(&server->inFlight)
-                                     < server->maxReq);
+                                   in_flight(server) < server->maxReq);
                         cifs_num_waiters_dec(server);
-                        spin_lock(&GlobalMid_Lock);
+                        spin_lock(&server->req_lock);
                 } else {
                         if (server->tcpStatus == CifsExiting) {
-                                spin_unlock(&GlobalMid_Lock);
+                                spin_unlock(&server->req_lock);
                                 return -ENOENT;
                         }
 
@@ -284,8 +285,8 @@ static int wait_for_free_request(struct TCP_Server_Info *server,
 
                         /* update # of requests on the wire to server */
                         if (long_op != CIFS_BLOCKING_OP)
-                                atomic_inc(&server->inFlight);
-                        spin_unlock(&GlobalMid_Lock);
+                                server->in_flight++;
+                        spin_unlock(&server->req_lock);
                         break;
                 }
         }
@@ -359,7 +360,7 @@ 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);
+                dec_in_flight(server);
                 wake_up(&server->request_q);
                 return -ENOMEM;
         }
@@ -392,7 +393,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
         return rc;
 out_err:
         delete_mid(mid);
-        atomic_dec(&server->inFlight);
+        dec_in_flight(server);
         wake_up(&server->request_q);
         return rc;
 }
@@ -564,7 +565,7 @@ 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);
+                dec_in_flight(ses->server);
                 wake_up(&ses->server->request_q);
                 return rc;
         }
@@ -601,7 +602,7 @@ 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);
+                        dec_in_flight(ses->server);
                         wake_up(&ses->server->request_q);
                         return rc;
                 }
@@ -612,7 +613,7 @@ 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);
+                dec_in_flight(ses->server);
                 wake_up(&ses->server->request_q);
                 return rc;
         }
@@ -637,7 +638,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
                 midQ->resp_buf = NULL;
 out:
         delete_mid(midQ);
-        atomic_dec(&ses->server->inFlight);
+        dec_in_flight(ses->server);
         wake_up(&ses->server->request_q);
 
         return rc;
@@ -688,7 +689,7 @@ 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);
+                dec_in_flight(ses->server);
                 wake_up(&ses->server->request_q);
                 return rc;
         }
@@ -721,7 +722,7 @@ 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);
+                        dec_in_flight(ses->server);
                         wake_up(&ses->server->request_q);
                         return rc;
                 }
@@ -730,7 +731,7 @@ 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);
+                dec_in_flight(ses->server);
                 wake_up(&ses->server->request_q);
                 return rc;
         }
@@ -747,7 +748,7 @@ 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);
+        dec_in_flight(ses->server);
         wake_up(&ses->server->request_q);
 
         return rc;