Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block

Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...

1 files changed, 10 insertions, 7 deletions

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 658c54b3b07a..11c5503d31dc 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1241,6 +1241,11 @@ void bch_initial_mark_key(struct cache_set *c, int level, struct bkey *k)
 	__bch_btree_mark_key(c, level, k);
 }
 
+void bch_update_bucket_in_use(struct cache_set *c, struct gc_stat *stats)
+{
+	stats->in_use = (c->nbuckets - c->avail_nbuckets) * 100 / c->nbuckets;
+}
+
 static bool btree_gc_mark_node(struct btree *b, struct gc_stat *gc)
 {
 	uint8_t stale = 0;
@@ -1652,9 +1657,8 @@ static void btree_gc_start(struct cache_set *c)
 	mutex_unlock(&c->bucket_lock);
 }
 
-static size_t bch_btree_gc_finish(struct cache_set *c)
+static void bch_btree_gc_finish(struct cache_set *c)
 {
-	size_t available = 0;
 	struct bucket *b;
 	struct cache *ca;
 	unsigned i;
@@ -1691,6 +1695,7 @@ static size_t bch_btree_gc_finish(struct cache_set *c)
 	}
 	rcu_read_unlock();
 
+	c->avail_nbuckets = 0;
 	for_each_cache(ca, c, i) {
 		uint64_t *i;
 
@@ -1712,18 +1717,16 @@ static size_t bch_btree_gc_finish(struct cache_set *c)
 			BUG_ON(!GC_MARK(b) && GC_SECTORS_USED(b));
 
 			if (!GC_MARK(b) || GC_MARK(b) == GC_MARK_RECLAIMABLE)
-				available++;
+				c->avail_nbuckets++;
 		}
 	}
 
 	mutex_unlock(&c->bucket_lock);
-	return available;
 }
 
 static void bch_btree_gc(struct cache_set *c)
 {
 	int ret;
-	unsigned long available;
 	struct gc_stat stats;
 	struct closure writes;
 	struct btree_op op;
@@ -1746,14 +1749,14 @@ static void bch_btree_gc(struct cache_set *c)
 			pr_warn("gc failed!");
 	} while (ret);
 
-	available = bch_btree_gc_finish(c);
+	bch_btree_gc_finish(c);
 	wake_up_allocators(c);
 
 	bch_time_stats_update(&c->btree_gc_time, start_time);
 
 	stats.key_bytes *= sizeof(uint64_t);
 	stats.data	<<= 9;
-	stats.in_use	= (c->nbuckets - available) * 100 / c->nbuckets;
+	bch_update_bucket_in_use(c, &stats);
 	memcpy(&c->gc_stats, &stats, sizeof(struct gc_stat));
 
 	trace_bcache_gc_end(c);