Merge tag 'for-linus-20180425' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "I ended up sitting on this about a week longer than I wanted to, since
  we were hashing out details with a timeout change. I've now killed
  that patch, so we can flush the existing queue in due time.

  This contains:

   - Fix for an old regression, where entering the queue can be
     disturbed by a signal to the process. This can cause spurious EIO.
     Fix from Alan Jenkins.

   - cdrom information leak fix from Dan.

   - Trivial helper for testing queue FUA from Dave Chinner, part of his
     O_DIRECT FUA series.

   - Series of swim fixes from Finn that actually makes it work again.

   - Loop O_DIRECT corruption fix, which caused data corruption in
     production for us. From me.

   - BFQ crash fix from me.

   - bcache maintainer update. Michael no longer has the time to do it,
     Coly has stepped up to serve as the new maintainer.

   - blkcg locking fixes from Jiang Biao.

   - Revert of a change from this merge window from Ming, that causes an
     issue on some hardware.

   - Minor clarification doc addition from Linus Walleij"

* tag 'for-linus-20180425' of git://git.kernel.dk/linux-block: (22 commits)
  Revert "blk-mq: remove code for dealing with remapping queue"
  block: mq: Add some minor doc for core structs
  bcache: mark Coly Li as bcache maintainer
  MAINTAINERS: Remove me as maintainer of bcache
  blkcg: init root blkcg_gq under lock
  blkcg: small fix on comment in blkcg_init_queue
  blkcg: don't hold blkcg lock when deactivating policy
  block: add blk_queue_fua() helper function
  cdrom: information leak in cdrom_ioctl_media_changed()
  bfq-iosched: ensure to clear bic/bfqq pointers when preparing request
  blk-mq: start request gstate with gen 1
  block/swim: Select appropriate drive on device open
  block/swim: Fix IO error at end of medium
  block/swim: Check drive type
  block/swim: Rename macros to avoid inconsistent inverted logic
  block/swim: Don't log an error message for an invalid ioctl
  block/swim: Remove extra put_disk() call from error path
  block/swim: Fix array bounds check
  m68k/mac: Don't remap SWIM MMIO region
  loop: handle short DIO reads
  ...

13 files changed, 144 insertions, 81 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 92be777d060a..dd66ae9a847e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2617,7 +2617,7 @@ S:	Maintained
 F:      drivers/net/hamradio/baycom*
 
 BCACHE (BLOCK LAYER CACHE)
-M:      Michael Lyle <mlyle@lyle.org>
+M:      Coly Li <colyli@suse.de>
 M:      Kent Overstreet <kent.overstreet@gmail.com>
 L:      linux-bcache@vger.kernel.org
 W:      http://bcache.evilpiepirate.org
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index f0ecd98509d8..771ae9730ac6 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -4934,8 +4934,16 @@ static void bfq_prepare_request(struct request *rq, struct bio *bio)
         bool new_queue = false;
         bool bfqq_already_existing = false, split = false;
 
-        if (!rq->elv.icq)
+        /*
+         * Even if we don't have an icq attached, we should still clear
+         * the scheduler pointers, as they might point to previously
+         * allocated bic/bfqq structs.
+         */
+        if (!rq->elv.icq) {
+                rq->elv.priv[0] = rq->elv.priv[1] = NULL;
                 return;
+        }
+
         bic = icq_to_bic(rq->elv.icq);
 
         spin_lock_irq(&bfqd->lock);
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 1c16694ae145..eb85cb87c40f 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1177,26 +1177,20 @@ int blkcg_init_queue(struct request_queue *q)
 
         preloaded = !radix_tree_preload(GFP_KERNEL);
 
-        /*
-         * Make sure the root blkg exists and count the existing blkgs.  As
-         * @q is bypassing at this point, blkg_lookup_create() can't be
-         * used.  Open code insertion.
-         */
+        /* Make sure the root blkg exists. */
         rcu_read_lock();
         spin_lock_irq(q->queue_lock);
         blkg = blkg_create(&blkcg_root, q, new_blkg);
+        if (IS_ERR(blkg))
+                goto err_unlock;
+        q->root_blkg = blkg;
+        q->root_rl.blkg = blkg;
         spin_unlock_irq(q->queue_lock);
         rcu_read_unlock();
 
         if (preloaded)
                 radix_tree_preload_end();
 
-        if (IS_ERR(blkg))
-                return PTR_ERR(blkg);
-
-        q->root_blkg = blkg;
-        q->root_rl.blkg = blkg;
-
         ret = blk_throtl_init(q);
         if (ret) {
                 spin_lock_irq(q->queue_lock);
@@ -1204,6 +1198,13 @@ int blkcg_init_queue(struct request_queue *q)
                 spin_unlock_irq(q->queue_lock);
         }
         return ret;
+
+err_unlock:
+        spin_unlock_irq(q->queue_lock);
+        rcu_read_unlock();
+        if (preloaded)
+                radix_tree_preload_end();
+        return PTR_ERR(blkg);
 }
 
 /**
@@ -1410,9 +1411,6 @@ void blkcg_deactivate_policy(struct request_queue *q,
         __clear_bit(pol->plid, q->blkcg_pols);
 
         list_for_each_entry(blkg, &q->blkg_list, q_node) {
-                /* grab blkcg lock too while removing @pd from @blkg */
-                spin_lock(&blkg->blkcg->lock);
-
                 if (blkg->pd[pol->plid]) {
                         if (!blkg->pd[pol->plid]->offline &&
                             pol->pd_offline_fn) {
@@ -1422,8 +1420,6 @@ void blkcg_deactivate_policy(struct request_queue *q,
                         pol->pd_free_fn(blkg->pd[pol->plid]);
                         blkg->pd[pol->plid] = NULL;
                 }
-
-                spin_unlock(&blkg->blkcg->lock);
         }
 
         spin_unlock_irq(q->queue_lock);
diff --git a/block/blk-core.c b/block/blk-core.c
index 806ce2442819..85909b431eb0 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -201,6 +201,10 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
         rq->part = NULL;
         seqcount_init(&rq->gstate_seq);
         u64_stats_init(&rq->aborted_gstate_sync);
+        /*
+         * See comment of blk_mq_init_request
+         */
+        WRITE_ONCE(rq->gstate, MQ_RQ_GEN_INC);
 }
 EXPORT_SYMBOL(blk_rq_init);
 
@@ -915,7 +919,6 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
 
         while (true) {
                 bool success = false;
-                int ret;
 
                 rcu_read_lock();
                 if (percpu_ref_tryget_live(&q->q_usage_counter)) {
@@ -947,14 +950,12 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
                  */
                 smp_rmb();
 
-                ret = wait_event_interruptible(q->mq_freeze_wq,
-                                (atomic_read(&q->mq_freeze_depth) == 0 &&
-                                 (preempt || !blk_queue_preempt_only(q))) ||
-                                blk_queue_dying(q));
+                wait_event(q->mq_freeze_wq,
+                           (atomic_read(&q->mq_freeze_depth) == 0 &&
+                            (preempt || !blk_queue_preempt_only(q))) ||
+                           blk_queue_dying(q));
                 if (blk_queue_dying(q))
                         return -ENODEV;
-                if (ret)
-                        return ret;
         }
 }
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 0dc9e341c2a7..c3621453ad87 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2042,6 +2042,13 @@ static int blk_mq_init_request(struct blk_mq_tag_set *set, struct request *rq,
 
         seqcount_init(&rq->gstate_seq);
         u64_stats_init(&rq->aborted_gstate_sync);
+        /*
+         * start gstate with gen 1 instead of 0, otherwise it will be equal
+         * to aborted_gstate, and be identified timed out by
+         * blk_mq_terminate_expired.
+         */
+        WRITE_ONCE(rq->gstate, MQ_RQ_GEN_INC);
+
         return 0;
 }
 
@@ -2329,7 +2336,7 @@ static void blk_mq_free_map_and_requests(struct blk_mq_tag_set *set,
 
 static void blk_mq_map_swqueue(struct request_queue *q)
 {