1 files changed, 47 insertions, 21 deletions

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index cf7eb891804f..153238fc4fa9 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -34,6 +34,7 @@
 #include "cifs_ioctl.h"
 #include "smbdirect.h"
 
+/* Change credits for different ops and return the total number of credits */
 static int
 change_conf(struct TCP_Server_Info *server)
 {
@@ -41,17 +42,15 @@ change_conf(struct TCP_Server_Info *server)
 	server->oplock_credits = server->echo_credits = 0;
 	switch (server->credits) {
 	case 0:
-		return -1;
+		return 0;
 	case 1:
 		server->echoes = false;
 		server->oplocks = false;
-		cifs_dbg(VFS, "disabling echoes and oplocks\n");
 		break;
 	case 2:
 		server->echoes = true;
 		server->oplocks = false;
 		server->echo_credits = 1;
-		cifs_dbg(FYI, "disabling oplocks\n");
 		break;
 	default:
 		server->echoes = true;
@@ -64,14 +63,15 @@ change_conf(struct TCP_Server_Info *server)
 		server->echo_credits = 1;
 	}
 	server->credits -= server->echo_credits + server->oplock_credits;
-	return 0;
+	return server->credits + server->echo_credits + server->oplock_credits;
 }
 
 static void
 smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
 		 const int optype)
 {
-	int *val, rc = 0;
+	int *val, rc = -1;
+
 	spin_lock(&server->req_lock);
 	val = server->ops->get_credits_field(server, optype);
 
@@ -101,8 +101,26 @@ smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
 	}
 	spin_unlock(&server->req_lock);
 	wake_up(&server->request_q);
-	if (rc)
-		cifs_reconnect(server);
+
+	if (server->tcpStatus == CifsNeedReconnect)
+		return;
+
+	switch (rc) {
+	case -1:
+		/* change_conf hasn't been executed */
+		break;
+	case 0:
+		cifs_dbg(VFS, "Possible client or server bug - zero credits\n");
+		break;
+	case 1:
+		cifs_dbg(VFS, "disabling echoes and oplocks\n");
+		break;
+	case 2:
+		cifs_dbg(FYI, "disabling oplocks\n");
+		break;
+	default:
+		cifs_dbg(FYI, "add %u credits total=%d\n", add, rc);
+	}
 }
 
 static void
@@ -136,7 +154,11 @@ smb2_get_credits(struct mid_q_entry *mid)
 {
 	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)mid->resp_buf;
 
-	return le16_to_cpu(shdr->CreditRequest);
+	if (mid->mid_state == MID_RESPONSE_RECEIVED
+	    || mid->mid_state == MID_RESPONSE_MALFORMED)
+		return le16_to_cpu(shdr->CreditRequest);
+
+	return 0;
 }
 
 static int
@@ -165,14 +187,14 @@ smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
 
 			scredits = server->credits;
 			/* can deadlock with reopen */
-			if (scredits == 1) {
+			if (scredits <= 8) {
 				*num = SMB2_MAX_BUFFER_SIZE;
 				*credits = 0;
 				break;
 			}
 
-			/* leave one credit for a possible reopen */
-			scredits--;
+			/* leave some credits for reopen and other ops */
+			scredits -= 8;
 			*num = min_t(unsigned int, size,
 				     scredits * SMB2_MAX_BUFFER_SIZE);
 
@@ -3189,11 +3211,23 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 			server->ops->is_status_pending(buf, server, 0))
 		return -1;
 
-	rdata->result = server->ops->map_error(buf, false);
+	/* set up first two iov to get credits */
+	rdata->iov[0].iov_base = buf;
+	rdata->iov[0].iov_len = 4;
+	rdata->iov[1].iov_base = buf + 4;
+	rdata->iov[1].iov_len =
+		min_t(unsigned int, buf_len, server->vals->read_rsp_size) - 4;
+	cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[0].iov_base, rdata->iov[0].iov_len);
+	cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
+		 rdata->iov[1].iov_base, rdata->iov[1].iov_len);
+
+	rdata->result = server->ops->map_error(buf, true);
 	if (rdata->result != 0) {
 		cifs_dbg(FYI, "%s: server returned error %d\n",
 			 __func__, rdata->result);
-		dequeue_mid(mid, rdata->result);
+		/* normal error on read response */
+		dequeue_mid(mid, false);
 		return 0;
 	}
 
@@ -3266,14 +3300,6 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 		return 0;
 	}
 
-	/* set up first iov for signature check */
-	rdata->iov[0].iov_base = buf;
-	rdata->iov[0].iov_len = 4;
-	rdata->iov[1].iov_base = buf + 4;
-	rdata->iov[1].iov_len = server->vals->read_rsp_size - 4;
-	cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
-		 rdata->iov[0].iov_base, server->vals->read_rsp_size);
-
 	length = rdata->copy_into_pages(server, rdata, &iter);
 
 	kfree(bvec);