cifs: add resp_buf_size to the mid_q_entry structure

and get rid of some more calls to get_rfc1002_length()

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

fs/cifs/cifsglob.h

@@ -1376,6 +1376,7 @@ struct mid_q_entry {
 	mid_handle_t *handle; /* call handle mid callback */
 	void *callback_data;	  /* general purpose pointer for callback */
 	void *resp_buf;		/* pointer to received SMB header */
+	unsigned int resp_buf_size;
 	int mid_state;	/* wish this were enum but can not pass to wait_event */
 	unsigned int mid_flags;
 	__le16 command;		/* smb command code */

fs/cifs/connect.c

@@ -928,6 +928,7 @@ cifs_demultiplex_thread(void *p)
 
 		server->lstrp = jiffies;
 		if (mid_entry != NULL) {
+			mid_entry->resp_buf_size = server->pdu_size;
 			if ((mid_entry->mid_flags & MID_WAIT_CANCELLED) &&
 			     mid_entry->mid_state == MID_RESPONSE_RECEIVED &&
 					server->ops->handle_cancelled_mid)

fs/cifs/smb2transport.c

@@ -604,7 +604,7 @@ int
 smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 		   bool log_error)
 {
-	unsigned int len = get_rfc1002_length(mid->resp_buf);
+	unsigned int len = mid->resp_buf_size;
 	struct kvec iov[2];
 	struct smb_rqst rqst = { .rq_iov = iov,
 				 .rq_nvec = 2 };

fs/cifs/transport.c

@@ -790,7 +790,7 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 
 	buf = (char *)midQ->resp_buf;
 	resp_iov->iov_base = buf;
-	resp_iov->iov_len = get_rfc1002_length(buf) +
+	resp_iov->iov_len = midQ->resp_buf_size +
 		ses->server->vals->header_preamble_size;
 	if (midQ->large_buf)
 		*resp_buf_type = CIFS_LARGE_BUFFER;