Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Another series of killing more code than what is being added, again
  thanks to Christoph's relentless cleanups and tech debt tackling.

  This contains:

   - blk-iocost improvements (Baolin Wang)

   - part0 iostat fix (Jeffle Xu)

   - Disable iopoll for split bios (Jeffle Xu)

   - block tracepoint cleanups (Christoph Hellwig)

   - Merging of struct block_device and hd_struct (Christoph Hellwig)

   - Rework/cleanup of how block device sizes are updated (Christoph
     Hellwig)

   - Simplification of gendisk lookup and removal of block device
     aliasing (Christoph Hellwig)

   - Block device ioctl cleanups (Christoph Hellwig)

   - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)

   - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)

   - sbitmap improvements (Pavel Begunkov)

   - Hybrid polling fix (Pavel Begunkov)

   - bvec iteration improvements (Pavel Begunkov)

   - Zone revalidation fixes (Damien Le Moal)

   - blk-throttle limit fix (Yu Kuai)

   - Various little fixes"

* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
  blk-mq: fix msec comment from micro to milli seconds
  blk-mq: update arg in comment of blk_mq_map_queue
  blk-mq: add helper allocating tagset->tags
  Revert "block: Fix a lockdep complaint triggered by request queue flushing"
  nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
  blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
  block: disable iopoll for split bio
  block: Improve blk_revalidate_disk_zones() checks
  sbitmap: simplify wrap check
  sbitmap: replace CAS with atomic and
  sbitmap: remove swap_lock
  sbitmap: optimise sbitmap_deferred_clear()
  blk-mq: skip hybrid polling if iopoll doesn't spin
  blk-iocost: Factor out the base vrate change into a separate function
  blk-iocost: Factor out the active iocgs' state check into a separate function
  blk-iocost: Move the usage ratio calculation to the correct place
  blk-iocost: Remove unnecessary advance declaration
  blk-iocost: Fix some typos in comments
  blktrace: fix up a kerneldoc comment
  block: remove the request_queue to argument request based tracepoints
  ...

1 files changed, 12 insertions, 6 deletions

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 97b7c2821565..808768f6b174 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -279,6 +279,14 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
 	return NULL;
 split:
 	*segs = nsegs;
+
+	/*
+	 * Bio splitting may cause subtle trouble such as hang when doing sync
+	 * iopoll in direct IO routine. Given performance gain of iopoll for
+	 * big IO can be trival, disable iopoll when split needed.
+	 */
+	bio->bi_opf &= ~REQ_HIPRI;
+
 	return bio_split(bio, sectors, GFP_NOIO, bs);
 }
 
@@ -338,7 +346,7 @@ void __blk_queue_split(struct bio **bio, unsigned int *nr_segs)
 		split->bi_opf |= REQ_NOMERGE;
 
 		bio_chain(split, *bio);
-		trace_block_split(q, split, (*bio)->bi_iter.bi_sector);
+		trace_block_split(split, (*bio)->bi_iter.bi_sector);
 		submit_bio_noacct(*bio);
 		*bio = split;
 	}
@@ -683,8 +691,6 @@ static void blk_account_io_merge_request(struct request *req)
 		part_stat_lock();
 		part_stat_inc(req->part, merges[op_stat_group(req_op(req))]);
 		part_stat_unlock();
-
-		hd_struct_put(req->part);
 	}
 }
 
@@ -801,7 +807,7 @@ static struct request *attempt_merge(struct request_queue *q,
 	 */
 	blk_account_io_merge_request(next);
 
-	trace_block_rq_merge(q, next);
+	trace_block_rq_merge(next);
 
 	/*
 	 * ownership of bio passed from next to req, return 'next' for
@@ -924,7 +930,7 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req,
 	if (!ll_back_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
 
-	trace_block_bio_backmerge(req->q, req, bio);
+	trace_block_bio_backmerge(bio);
 	rq_qos_merge(req->q, req, bio);
 
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
@@ -948,7 +954,7 @@ static enum bio_merge_status bio_attempt_front_merge(struct request *req,
 	if (!ll_front_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
 
-	trace_block_bio_frontmerge(req->q, req, bio);
+	trace_block_bio_frontmerge(bio);
 	rq_qos_merge(req->q, req, bio);
 
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)