1 files changed, 45 insertions, 42 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 3851d0aaa288..b42050c68e6c 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -270,26 +270,7 @@ smb_rqst_len(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 	for (i = 0; i < nvec; i++)
 		buflen += iov[i].iov_len;
 
-	/*
-	 * Add in the page array if there is one. The caller needs to make
-	 * sure rq_offset and rq_tailsz are set correctly. If a buffer of
-	 * multiple pages ends at page boundary, rq_tailsz needs to be set to
-	 * PAGE_SIZE.
-	 */
-	if (rqst->rq_npages) {
-		if (rqst->rq_npages == 1)
-			buflen += rqst->rq_tailsz;
-		else {
-			/*
-			 * If there is more than one page, calculate the
-			 * buffer length based on rq_offset and rq_tailsz
-			 */
-			buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) -
-					rqst->rq_offset;
-			buflen += rqst->rq_tailsz;
-		}
-	}
-
+	buflen += iov_iter_count(&rqst->rq_iter);
 	return buflen;
 }
 
@@ -376,23 +357,15 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 
 		total_len += sent;
 
-		/* now walk the page array and send each page in it */
-		for (i = 0; i < rqst[j].rq_npages; i++) {
-			struct bio_vec bvec;
-
-			bvec.bv_page = rqst[j].rq_pages[i];
-			rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
-					     &bvec.bv_offset);
-
-			iov_iter_bvec(&smb_msg.msg_iter, ITER_SOURCE,
-				      &bvec, 1, bvec.bv_len);
+		if (iov_iter_count(&rqst[j].rq_iter) > 0) {
+			smb_msg.msg_iter = rqst[j].rq_iter;
 			rc = smb_send_kvec(server, &smb_msg, &sent);
 			if (rc < 0)
 				break;
-
 			total_len += sent;
 		}
-	}
+
+}
 
 unmask:
 	sigprocmask(SIG_SETMASK, &oldmask, NULL);
@@ -1034,15 +1007,40 @@ cifs_cancelled_callback(struct mid_q_entry *mid)
 struct TCP_Server_Info *cifs_pick_channel(struct cifs_ses *ses)
 {
 	uint index = 0;
+	unsigned int min_in_flight = UINT_MAX, max_in_flight = 0;
+	struct TCP_Server_Info *server = NULL;
+	int i;
 
 	if (!ses)
 		return NULL;
 
-	/* round robin */
-	index = (uint)atomic_inc_return(&ses->chan_seq);
-
 	spin_lock(&ses->chan_lock);
-	index %= ses->chan_count;
+	for (i = 0; i < ses->chan_count; i++) {
+		server = ses->chans[i].server;
+		if (!server)
+			continue;
+
+		/*
+		 * strictly speaking, we should pick up req_lock to read
+		 * server->in_flight. But it shouldn't matter much here if we
+		 * race while reading this data. The worst that can happen is
+		 * that we could use a channel that's not least loaded. Avoiding
+		 * taking the lock could help reduce wait time, which is
+		 * important for this function
+		 */
+		if (server->in_flight < min_in_flight) {
+			min_in_flight = server->in_flight;
+			index = i;
+		}
+		if (server->in_flight > max_in_flight)
+			max_in_flight = server->in_flight;
+	}
+
+	/* if all channels are equally loaded, fall back to round-robin */
+	if (min_in_flight == max_in_flight) {
+		index = (uint)atomic_inc_return(&ses->chan_seq);
+		index %= ses->chan_count;
+	}
 	spin_unlock(&ses->chan_lock);
 
 	return ses->chans[index].server;
@@ -1640,11 +1638,11 @@ int
 cifs_discard_remaining_data(struct TCP_Server_Info *server)
 {
 	unsigned int rfclen = server->pdu_size;
-	int remaining = rfclen + HEADER_PREAMBLE_SIZE(server) -
+	size_t remaining = rfclen + HEADER_PREAMBLE_SIZE(server) -
 		server->total_read;
 
 	while (remaining > 0) {
-		int length;
+		ssize_t length;
 
 		length = cifs_discard_from_socket(server,
 				min_t(size_t, remaining,
@@ -1790,10 +1788,15 @@ cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		return cifs_readv_discard(server, mid);
 	}
 
-	length = rdata->read_into_pages(server, rdata, data_len);
-	if (length < 0)
-		return length;
-
+#ifdef CONFIG_CIFS_SMB_DIRECT
+	if (rdata->mr)
+		length = data_len; /* An RDMA read is already done. */
+	else
+#endif
+		length = cifs_read_iter_from_socket(server, &rdata->iter,
+						    data_len);
+	if (length > 0)
+		rdata->got_bytes += length;
 	server->total_read += length;
 
 	cifs_dbg(FYI, "total_read=%u buflen=%u remaining=%u\n",