Merge tag 'for-linus-20190524' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - NVMe pull request from Keith, with fixes from a few folks.

 - bio and sbitmap before atomic barrier fixes (Andrea)

 - Hang fix for blk-mq freeze and unfreeze (Bob)

 - Single segment count regression fix (Christoph)

 - AoE now has a new maintainer

 - tools/io_uring/ Makefile fix, and sync with liburing (me)

* tag 'for-linus-20190524' of git://git.kernel.dk/linux-block: (23 commits)
  tools/io_uring: sync with liburing
  tools/io_uring: fix Makefile for pthread library link
  blk-mq: fix hang caused by freeze/unfreeze sequence
  block: remove the bi_seg_{front,back}_size fields in struct bio
  block: remove the segment size check in bio_will_gap
  block: force an unlimited segment size on queues with a virt boundary
  block: don't decrement nr_phys_segments for physically contigous segments
  sbitmap: fix improper use of smp_mb__before_atomic()
  bio: fix improper use of smp_mb__before_atomic()
  aoe: list new maintainer for aoe driver
  nvme-pci: use blk-mq mapping for unmanaged irqs
  nvme: update MAINTAINERS
  nvme: copy MTFA field from identify controller
  nvme: fix memory leak for power latency tolerance
  nvme: release namespace SRCU protection before performing controller ioctls
  nvme: merge nvme_ns_ioctl into nvme_ioctl
  nvme: remove the ifdef around nvme_nvm_ioctl
  nvme: fix srcu locking on error return in nvme_get_ns_from_disk
  nvme: Fix known effects
  nvme-pci: Sync queues on reset
  ...

3 files changed, 7 insertions, 9 deletions

diff --git a/include/linux/bio.h b/include/linux/bio.h
index ea73df36529a..0f23b5682640 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -210,7 +210,7 @@ static inline void bio_cnt_set(struct bio *bio, unsigned int count)
 {
 	if (count != 1) {
 		bio->bi_flags |= (1 << BIO_REFFED);
-		smp_mb__before_atomic();
+		smp_mb();
 	}
 	atomic_set(&bio->__bi_cnt, count);
 }
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index be418275763c..95202f80676c 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -159,13 +159,6 @@ struct bio {
 	 */
 	unsigned int		bi_phys_segments;
 
-	/*
-	 * To keep track of the max segment size, we account for the
-	 * sizes of the first and last mergeable segments in this bio.
-	 */
-	unsigned int		bi_seg_front_size;
-	unsigned int		bi_seg_back_size;
-
 	struct bvec_iter	bi_iter;
 
 	atomic_t		__bi_remaining;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 1aafeb923e7b..592669bcc536 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -542,7 +542,7 @@ struct request_queue {
 	struct list_head	unused_hctx_list;
 	spinlock_t		unused_hctx_lock;
 
-	atomic_t		mq_freeze_depth;
+	int			mq_freeze_depth;
 
 #if defined(CONFIG_BLK_DEV_BSG)
 	struct bsg_class_device bsg_dev;
@@ -554,6 +554,11 @@ struct request_queue {
 #endif
 	struct rcu_head		rcu_head;
 	wait_queue_head_t	mq_freeze_wq;
+	/*
+	 * Protect concurrent access to q_usage_counter by
+	 * percpu_ref_kill() and percpu_ref_reinit().
+	 */
+	struct mutex		mq_freeze_lock;
 	struct percpu_ref	q_usage_counter;
 
 	struct blk_mq_tag_set	*tag_set;