CIFS: Extend credit mechanism to process request type

Split all requests to echos, oplocks and others - each group uses
its own credit slot. This is indicated by new flags

CIFS_ECHO_OP and CIFS_OBREAK_OP

that are not used now for CIFS. This change is required to support
SMB2 protocol because of different processing of these commands.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 39 insertions, 31 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 3e6ffe35538..904702db252 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -250,13 +250,13 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
 }
 
 static int
-wait_for_free_credits(struct TCP_Server_Info *server, const int optype,
+wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
 		      int *credits)
 {
 	int rc;
 
 	spin_lock(&server->req_lock);
-	if (optype == CIFS_ASYNC_OP) {
+	if (timeout == CIFS_ASYNC_OP) {
 		/* oplock breaks must not be held up */
 		server->in_flight++;
 		*credits -= 1;
@@ -286,7 +286,7 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int optype,
 			 */
 
 			/* update # of requests on the wire to server */
-			if (optype != CIFS_BLOCKING_OP) {
+			if (timeout != CIFS_BLOCKING_OP) {
 				*credits -= 1;
 				server->in_flight++;
 			}
@@ -298,10 +298,11 @@ wait_for_free_credits(struct TCP_Server_Info *server, const int optype,
 }
 
 static int
-wait_for_free_request(struct TCP_Server_Info *server, const int optype)
+wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
+		      const int optype)
 {
-	return wait_for_free_credits(server, optype,
-				     server->ops->get_credits_field(server));
+	return wait_for_free_credits(server, timeout,
+				server->ops->get_credits_field(server, optype));
 }
 
 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
@@ -378,12 +379,15 @@ cifs_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov,
 int
 cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 		unsigned int nvec, mid_receive_t *receive,
-		mid_callback_t *callback, void *cbdata, bool ignore_pend)
+		mid_callback_t *callback, void *cbdata, const int flags)
 {
-	int rc;
+	int rc, timeout, optype;
 	struct mid_q_entry *mid;
 
-	rc = wait_for_free_request(server, ignore_pend ? CIFS_ASYNC_OP : 0);
+	timeout = flags & CIFS_TIMEOUT_MASK;
+	optype = flags & CIFS_OP_MASK;
+
+	rc = wait_for_free_request(server, timeout, optype);
 	if (rc)
 		return rc;
 
@@ -391,7 +395,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 	rc = cifs_setup_async_request(server, iov, nvec, &mid);
 	if (rc) {
 		mutex_unlock(&server->srv_mutex);
-		add_credits(server, 1);
+		add_credits(server, 1, optype);
 		wake_up(&server->request_q);
 		return rc;
 	}
@@ -417,7 +421,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
 		return 0;
 
 	delete_mid(mid);
-	add_credits(server, 1);
+	add_credits(server, 1, optype);
 	wake_up(&server->request_q);
 	return rc;
 }
@@ -533,17 +537,19 @@ cifs_setup_request(struct cifs_ses *ses, struct kvec *iov,
 
 int
 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
-	     struct kvec *iov, int n_vec, int *pRespBufType /* ret */,
+	     struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
 	     const int flags)
 {
 	int rc = 0;
-	int long_op;
+	int timeout, optype;
 	struct mid_q_entry *midQ;
 	char *buf = iov[0].iov_base;
+	unsigned int credits = 1;
 
-	long_op = flags & CIFS_TIMEOUT_MASK;
+	timeout = flags & CIFS_TIMEOUT_MASK;
+	optype = flags & CIFS_OP_MASK;
 
-	*pRespBufType = CIFS_NO_BUFFER;  /* no response buf yet */
+	*resp_buf_type = CIFS_NO_BUFFER;  /* no response buf yet */
 
 	if ((ses == NULL) || (ses->server == NULL)) {
 		cifs_small_buf_release(buf);
@@ -562,7 +568,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 	 * use ses->maxReq.
 	 */
 
-	rc = wait_for_free_request(ses->server, long_op);
+	rc = wait_for_free_request(ses->server, timeout, optype);
 	if (rc) {
 		cifs_small_buf_release(buf);
 		return rc;
@@ -581,7 +587,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 		mutex_unlock(&ses->server->srv_mutex);
 		cifs_small_buf_release(buf);
 		/* Update # of requests on wire to server */
-		add_credits(ses->server, 1);
+		add_credits(ses->server, 1, optype);
 		return rc;
 	}
 
@@ -598,7 +604,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 		goto out;
 	}
 
-	if (long_op == CIFS_ASYNC_OP) {
+	if (timeout == CIFS_ASYNC_OP) {
 		cifs_small_buf_release(buf);
 		goto out;
 	}
@@ -611,7 +617,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
 			cifs_small_buf_release(buf);
-			add_credits(ses->server, 1);
+			add_credits(ses->server, 1, optype);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
@@ -621,7 +627,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		add_credits(ses->server, 1);
+		add_credits(ses->server, 1, optype);
 		return rc;
 	}
 
@@ -635,9 +641,11 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 	iov[0].iov_base = buf;
 	iov[0].iov_len = get_rfc1002_length(buf) + 4;
 	if (midQ->large_buf)
-		*pRespBufType = CIFS_LARGE_BUFFER;
+		*resp_buf_type = CIFS_LARGE_BUFFER;
 	else
-		*pRespBufType = CIFS_SMALL_BUFFER;
+		*resp_buf_type = CIFS_SMALL_BUFFER;
+
+	credits = ses->server->ops->get_credits(midQ);
 
 	rc = ses->server->ops->check_receive(midQ, ses->server,
 					     flags & CIFS_LOG_ERROR);
@@ -647,7 +655,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses,
 		midQ->resp_buf = NULL;
 out:
 	delete_mid(midQ);
-	add_credits(ses->server, 1);
+	add_credits(ses->server, credits, optype);
 
 	return rc;
 }
@@ -655,7 +663,7 @@ out:
 int
 SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	    struct smb_hdr *in_buf, struct smb_hdr *out_buf,
-	    int *pbytes_returned, const int long_op)
+	    int *pbytes_returned, const int timeout)
 {
 	int rc = 0;
 	struct mid_q_entry *midQ;
@@ -683,7 +691,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 		return -EIO;
 	}
 
-	rc = wait_for_free_request(ses->server, long_op);
+	rc = wait_for_free_request(ses->server, timeout, 0);
 	if (rc)
 		return rc;
 
@@ -697,7 +705,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	if (rc) {
 		mutex_unlock(&ses->server->srv_mutex);
 		/* Update # of requests on wire to server */
-		add_credits(ses->server, 1);
+		add_credits(ses->server, 1, 0);
 		return rc;
 	}
 
@@ -718,7 +726,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	if (rc < 0)
 		goto out;
 
-	if (long_op == CIFS_ASYNC_OP)
+	if (timeout == CIFS_ASYNC_OP)
 		goto out;
 
 	rc = wait_for_response(ses->server, midQ);
@@ -729,7 +737,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 			/* no longer considered to be "in-flight" */
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
-			add_credits(ses->server, 1);
+			add_credits(ses->server, 1, 0);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
@@ -737,7 +745,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		add_credits(ses->server, 1);
+		add_credits(ses->server, 1, 0);
 		return rc;
 	}
 
@@ -753,7 +761,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	rc = cifs_check_receive(midQ, ses->server, 0);
 out:
 	delete_mid(midQ);
-	add_credits(ses->server, 1);
+	add_credits(ses->server, 1, 0);
 
 	return rc;
 }
@@ -818,7 +826,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 		return -EIO;
 	}
 
-	rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP);
+	rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
 	if (rc)
 		return rc;