Merge branch 'for-4.13/block' of git://git.kernel.dk/linux-block

Pull core block/IO updates from Jens Axboe:
 "This is the main pull request for the block layer for 4.13. Not a huge
  round in terms of features, but there's a lot of churn related to some
  core cleanups.

  Note this depends on the UUID tree pull request, that Christoph
  already sent out.

  This pull request contains:

   - A series from Christoph, unifying the error/stats codes in the
     block layer. We now use blk_status_t everywhere, instead of using
     different schemes for different places.

   - Also from Christoph, some cleanups around request allocation and IO
     scheduler interactions in blk-mq.

   - And yet another series from Christoph, cleaning up how we handle
     and do bounce buffering in the block layer.

   - A blk-mq debugfs series from Bart, further improving on the support
     we have for exporting internal information to aid debugging IO
     hangs or stalls.

   - Also from Bart, a series that cleans up the request initialization
     differences across types of devices.

   - A series from Goldwyn Rodrigues, allowing the block layer to return
     failure if we will block and the user asked for non-blocking.

   - Patch from Hannes for supporting setting loop devices block size to
     that of the underlying device.

   - Two series of patches from Javier, fixing various issues with
     lightnvm, particular around pblk.

   - A series from me, adding support for write hints. This comes with
     NVMe support as well, so applications can help guide data placement
     on flash to improve performance, latencies, and write
     amplification.

   - A series from Ming, improving and hardening blk-mq support for
     stopping/starting and quiescing hardware queues.

   - Two pull requests for NVMe updates. Nothing major on the feature
     side, but lots of cleanups and bug fixes. From the usual crew.

   - A series from Neil Brown, greatly improving the bio rescue set
     support. Most notably, this kills the bio rescue work queues, if we
     don't really need them.

   - Lots of other little bug fixes that are all over the place"

* 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits)
  lightnvm: pblk: set line bitmap check under debug
  lightnvm: pblk: verify that cache read is still valid
  lightnvm: pblk: add initialization check
  lightnvm: pblk: remove target using async. I/Os
  lightnvm: pblk: use vmalloc for GC data buffer
  lightnvm: pblk: use right metadata buffer for recovery
  lightnvm: pblk: schedule if data is not ready
  lightnvm: pblk: remove unused return variable
  lightnvm: pblk: fix double-free on pblk init
  lightnvm: pblk: fix bad le64 assignations
  nvme: Makefile: remove dead build rule
  blk-mq: map all HWQ also in hyperthreaded system
  nvmet-rdma: register ib_client to not deadlock in device removal
  nvme_fc: fix error recovery on link down.
  nvmet_fc: fix crashes on bad opcodes
  nvme_fc: Fix crash when nvme controller connection fails.
  nvme_fc: replace ioabort msleep loop with completion
  nvme_fc: fix double calls to nvme_cleanup_cmd()
  nvme-fabrics: verify that a controller returns the correct NQN
  nvme: simplify nvme_dev_attrs_are_visible
  ...

1 files changed, 38 insertions, 47 deletions

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 3df056b73b66..0e8ab5bb3575 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -559,13 +559,13 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio, struct dm_m
 		if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags))
 			return DM_MAPIO_REQUEUE;
 		dm_report_EIO(m);
-		return -EIO;
+		return DM_MAPIO_KILL;
 	}
 
 	mpio->pgpath = pgpath;
 	mpio->nr_bytes = nr_bytes;
 
-	bio->bi_error = 0;
+	bio->bi_status = 0;
 	bio->bi_bdev = pgpath->path.dev->bdev;
 	bio->bi_opf |= REQ_FAILFAST_TRANSPORT;
 
@@ -621,11 +621,19 @@ static void process_queued_bios(struct work_struct *work)
 	blk_start_plug(&plug);
 	while ((bio = bio_list_pop(&bios))) {
 		r = __multipath_map_bio(m, bio, get_mpio_from_bio(bio));
-		if (r < 0 || r == DM_MAPIO_REQUEUE) {
-			bio->bi_error = r;
+		switch (r) {
+		case DM_MAPIO_KILL:
+			bio->bi_status = BLK_STS_IOERR;
+			bio_endio(bio);
+			break;
+		case DM_MAPIO_REQUEUE:
+			bio->bi_status = BLK_STS_DM_REQUEUE;
 			bio_endio(bio);
-		} else if (r == DM_MAPIO_REMAPPED)
+			break;
+		case DM_MAPIO_REMAPPED:
 			generic_make_request(bio);
+			break;
+		}
 	}
 	blk_finish_plug(&plug);
 }
@@ -1442,22 +1450,15 @@ static void activate_path_work(struct work_struct *work)
 	activate_or_offline_path(pgpath);
 }
 
-static int noretry_error(int error)
+static int noretry_error(blk_status_t error)
 {
 	switch (error) {
-	case -EBADE:
-		/*
-		 * EBADE signals an reservation conflict.
-		 * We shouldn't fail the path here as we can communicate with
-		 * the target.  We should failover to the next path, but in
-		 * doing so we might be causing a ping-pong between paths.
-		 * So just return the reservation conflict error.
-		 */
-	case -EOPNOTSUPP:
-	case -EREMOTEIO:
-	case -EILSEQ:
-	case -ENODATA:
-	case -ENOSPC:
+	case BLK_STS_NOTSUPP:
+	case BLK_STS_NOSPC:
+	case BLK_STS_TARGET:
+	case BLK_STS_NEXUS:
+	case BLK_STS_MEDIUM:
+	case BLK_STS_RESOURCE:
 		return 1;
 	}
 
@@ -1466,7 +1467,7 @@ static int noretry_error(int error)
 }
 
 static int multipath_end_io(struct dm_target *ti, struct request *clone,
-			    int error, union map_info *map_context)
+			    blk_status_t error, union map_info *map_context)
 {
 	struct dm_mpath_io *mpio = get_mpio(map_context);
 	struct pgpath *pgpath = mpio->pgpath;
@@ -1493,7 +1494,7 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
 
 		if (atomic_read(&m->nr_valid_paths) == 0 &&
 		    !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
-			if (error == -EIO)
+			if (error == BLK_STS_IOERR)
 				dm_report_EIO(m);
 			/* complete with the original error */
 			r = DM_ENDIO_DONE;
@@ -1510,24 +1511,26 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
 	return r;
 }
 
-static int do_end_io_bio(struct multipath *m, struct bio *clone,
-			 int error, struct dm_mpath_io *mpio)
+static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone,
+		blk_status_t *error)
 {
+	struct multipath *m = ti->private;
+	struct dm_mpath_io *mpio = get_mpio_from_bio(clone);
+	struct pgpath *pgpath = mpio->pgpath;
 	unsigned long flags;
+	int r = DM_ENDIO_DONE;
 
-	if (!error)
-		return 0;	/* I/O complete */
-
-	if (noretry_error(error))
-		return error;
+	if (!*error || noretry_error(*error))
+		goto done;
 
-	if (mpio->pgpath)
-		fail_path(mpio->pgpath);
+	if (pgpath)
+		fail_path(pgpath);
 
 	if (atomic_read(&m->nr_valid_paths) == 0 &&
 	    !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
 		dm_report_EIO(m);
-		return -EIO;
+		*error = BLK_STS_IOERR;
+		goto done;
 	}
 
 	/* Queue for the daemon to resubmit */
@@ -1539,23 +1542,11 @@ static int do_end_io_bio(struct multipath *m, struct bio *clone,
 	if (!test_bit(MPATHF_QUEUE_IO, &m->flags))
 		queue_work(kmultipathd, &m->process_queued_bios);
 
-	return DM_ENDIO_INCOMPLETE;
-}
-
-static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int error)
-{
-	struct multipath *m = ti->private;
-	struct dm_mpath_io *mpio = get_mpio_from_bio(clone);
-	struct pgpath *pgpath;
-	struct path_selector *ps;
-	int r;
-
-	BUG_ON(!mpio);
-
-	r = do_end_io_bio(m, clone, error, mpio);
-	pgpath = mpio->pgpath;
+	r = DM_ENDIO_INCOMPLETE;
+done:
 	if (pgpath) {
-		ps = &pgpath->pg->ps;
+		struct path_selector *ps = &pgpath->pg->ps;
+
 		if (ps->type->end_io)
 			ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
 	}