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);