Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "This is the first pull request for 4.14, containing most of the code
  changes. It's a quiet series this round, which I think we needed after
  the churn of the last few series. This contains:

   - Fix for a registration race in loop, from Anton Volkov.

   - Overflow complaint fix from Arnd for DAC960.

   - Series of drbd changes from the usual suspects.

   - Conversion of the stec/skd driver to blk-mq. From Bart.

   - A few BFQ improvements/fixes from Paolo.

   - CFQ improvement from Ritesh, allowing idling for group idle.

   - A few fixes found by Dan's smatch, courtesy of Dan.

   - A warning fixup for a race between changing the IO scheduler and
     device remova. From David Jeffery.

   - A few nbd fixes from Josef.

   - Support for cgroup info in blktrace, from Shaohua.

   - Also from Shaohua, new features in the null_blk driver to allow it
     to actually hold data, among other things.

   - Various corner cases and error handling fixes from Weiping Zhang.

   - Improvements to the IO stats tracking for blk-mq from me. Can
     drastically improve performance for fast devices and/or big
     machines.

   - Series from Christoph removing bi_bdev as being needed for IO
     submission, in preparation for nvme multipathing code.

   - Series from Bart, including various cleanups and fixes for switch
     fall through case complaints"

* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
  kernfs: checking for IS_ERR() instead of NULL
  drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
  drbd: Fix allyesconfig build, fix recent commit
  drbd: switch from kmalloc() to kmalloc_array()
  drbd: abort drbd_start_resync if there is no connection
  drbd: move global variables to drbd namespace and make some static
  drbd: rename "usermode_helper" to "drbd_usermode_helper"
  drbd: fix race between handshake and admin disconnect/down
  drbd: fix potential deadlock when trying to detach during handshake
  drbd: A single dot should be put into a sequence.
  drbd: fix rmmod cleanup, remove _all_ debugfs entries
  drbd: Use setup_timer() instead of init_timer() to simplify the code.
  drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
  drbd: new disk-option disable-write-same
  drbd: Fix resource role for newly created resources in events2
  drbd: mark symbols static where possible
  drbd: Send P_NEG_ACK upon write error in protocol != C
  drbd: add explicit plugging when submitting batches
  drbd: change list_for_each_safe to while(list_first_entry_or_null)
  drbd: introduce drbd_recv_header_maybe_unplug
  ...

1 files changed, 52 insertions, 8 deletions

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index c7e95e6380fb..796eaf347dc0 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -332,7 +332,7 @@ static void drbd_free_pages(struct drbd_device *device, struct page *page, int i
 	if (page == NULL)
 		return;
 
-	if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count)
+	if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * drbd_minor_count)
 		i = page_chain_free(page);
 	else {
 		struct page *tmp;
@@ -1100,7 +1100,10 @@ randomize:
 	idr_for_each_entry(&connection->peer_devices, peer_device, vnr)
 		mutex_lock(peer_device->device->state_mutex);
 
+	/* avoid a race with conn_request_state( C_DISCONNECTING ) */
+	spin_lock_irq(&connection->resource->req_lock);
 	set_bit(STATE_SENT, &connection->flags);
+	spin_unlock_irq(&connection->resource->req_lock);
 
 	idr_for_each_entry(&connection->peer_devices, peer_device, vnr)
 		mutex_unlock(peer_device->device->state_mutex);
@@ -1194,6 +1197,14 @@ static int decode_header(struct drbd_connection *connection, void *header, struc
 	return 0;
 }
 
+static void drbd_unplug_all_devices(struct drbd_connection *connection)
+{
+	if (current->plug == &connection->receiver_plug) {
+		blk_finish_plug(&connection->receiver_plug);
+		blk_start_plug(&connection->receiver_plug);
+	} /* else: maybe just schedule() ?? */
+}
+
 static int drbd_recv_header(struct drbd_connection *connection, struct packet_info *pi)
 {
 	void *buffer = connection->data.rbuf;
@@ -1209,6 +1220,36 @@ static int drbd_recv_header(struct drbd_connection *connection, struct packet_in
 	return err;
 }
 
+static int drbd_recv_header_maybe_unplug(struct drbd_connection *connection, struct packet_info *pi)
+{
+	void *buffer = connection->data.rbuf;
+	unsigned int size = drbd_header_size(connection);
+	int err;
+
+	err = drbd_recv_short(connection->data.socket, buffer, size, MSG_NOSIGNAL|MSG_DONTWAIT);
+	if (err != size) {
+		/* If we have nothing in the receive buffer now, to reduce
+		 * application latency, try to drain the backend queues as
+		 * quickly as possible, and let remote TCP know what we have
+		 * received so far. */
+		if (err == -EAGAIN) {
+			drbd_tcp_quickack(connection->data.socket);
+			drbd_unplug_all_devices(connection);
+		}
+		if (err > 0) {
+			buffer += err;
+			size -= err;
+		}
+		err = drbd_recv_all_warn(connection, buffer, size);
+		if (err)
+			return err;
+	}
+
+	err = decode_header(connection, connection->data.rbuf, pi);
+	connection->last_received = jiffies;
+
+	return err;
+}
 /* This is blkdev_issue_flush, but asynchronous.
  * We want to submit to all component volumes in parallel,
  * then wait for all completions.
@@ -1223,7 +1264,7 @@ struct one_flush_context {
 	struct issue_flush_context *ctx;
 };
 
-void one_flush_endio(struct bio *bio)
+static void one_flush_endio(struct bio *bio)
 {
 	struct one_flush_context *octx = bio->bi_private;
 	struct drbd_device *device = octx->device;
@@ -1265,7 +1306,7 @@ static void submit_one_flush(struct drbd_device *device, struct issue_flush_cont
 
 	octx->device = device;
 	octx->ctx = ctx;
-	bio->bi_bdev = device->ldev->backing_bdev;
+	bio_set_dev(bio, device->ldev->backing_bdev);
 	bio->bi_private = octx;
 	bio->bi_end_io = one_flush_endio;
 	bio->bi_opf = REQ_OP_FLUSH | REQ_PREFLUSH;
@@ -1548,7 +1589,7 @@ next_bio:
 	}
 	/* > peer_req->i.sector, unless this is the first bio */
 	bio->bi_iter.bi_sector = sector;
-	bio->bi_bdev = device->ldev->backing_bdev;
+	bio_set_dev(bio, device->ldev->backing_bdev);
 	bio_set_op_attrs(bio, op, op_flags);
 	bio->bi_private = peer_req;
 	bio->bi_end_io = drbd_peer_request_endio;
@@ -4085,7 +4126,7 @@ static int receive_uuids(struct drbd_connection *connection, struct packet_info
 		return config_unknown_volume(connection, pi);
 	device = peer_device->device;
 
-	p_uuid = kmalloc(sizeof(u64)*UI_EXTENDED_SIZE, GFP_NOIO);
+	p_uuid = kmalloc_array(UI_EXTENDED_SIZE, sizeof(*p_uuid), GFP_NOIO);
 	if (!p_uuid) {
 		drbd_err(device, "kmalloc of p_uuid failed\n");
 		return false;
@@ -4882,8 +4923,8 @@ static void drbdd(struct drbd_connection *connection)
 		struct data_cmd const *cmd;
 
 		drbd_thread_current_set_cpu(&connection->receiver);
-		update_receiver_timing_details(connection, drbd_recv_header);
-		if (drbd_recv_header(connection, &pi))
+		update_receiver_timing_details(connection, drbd_recv_header_maybe_unplug);
+		if (drbd_recv_header_maybe_unplug(connection, &pi))
 			goto err_out;
 
 		cmd = &drbd_cmd_handler[pi.cmd];
@@ -5375,8 +5416,11 @@ int drbd_receiver(struct drbd_thread *thi)
 		}
 	} while (h == 0);
 
-	if (h > 0)
+	if (h > 0) {
+		blk_start_plug(&connection->receiver_plug);
 		drbdd(connection);
+		blk_finish_plug(&connection->receiver_plug);
+	}
 
 	conn_disconnect(connection);