Merge branch 'bcache-for-3.11' of git://evilpiepirate.org/~kent/linux-bcache into for-3.11/drivers

Kent writes:

Hey Jens - I've been busy torture testing and chasing bugs, here's the
fruits of my labors. These are all fairly small fixes, some of them
quite important.

8 files changed, 61 insertions, 31 deletions

diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index b54b73b9b2b7..e45f5575fd4d 100644
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -63,6 +63,7 @@
 #include "bcache.h"
 #include "btree.h"
 
+#include <linux/freezer.h>
 #include <linux/kthread.h>
 #include <linux/random.h>
 #include <trace/events/bcache.h>
@@ -363,11 +364,10 @@ do {									\
                         break;                                          \
                                                                         \
                 mutex_unlock(&(ca)->set->bucket_lock);                  \
-                if (test_bit(CACHE_SET_STOPPING_2, &ca->set->flags)) {  \
-                        closure_put(&ca->set->cl);                      \
+                if (kthread_should_stop())                              \
                         return 0;                                       \
-                }                                                       \
                                                                         \
+                try_to_freeze();                                        \
                 schedule();                                             \
                 mutex_lock(&(ca)->set->bucket_lock);                    \
         }                                                               \
@@ -547,14 +547,12 @@ int bch_bucket_alloc_set(struct cache_set *c, unsigned watermark,
 
 int bch_cache_allocator_start(struct cache *ca)
 {
-        ca->alloc_thread = kthread_create(bch_allocator_thread,
-                                          ca, "bcache_allocator");
-        if (IS_ERR(ca->alloc_thread))
-                return PTR_ERR(ca->alloc_thread);
-
-        closure_get(&ca->set->cl);
-        wake_up_process(ca->alloc_thread);
+        struct task_struct *k = kthread_run(bch_allocator_thread,
+                                            ca, "bcache_allocator");
+        if (IS_ERR(k))
+                return PTR_ERR(k);
 
+        ca->alloc_thread = k;
         return 0;
 }
 
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 342ba86c6e4f..b39f6f0b45f2 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -434,6 +434,7 @@ struct bcache_device {
 
         /* If nonzero, we're detaching/unregistering from cache set */
         atomic_t                detaching;
+        int                     flush_done;
 
         uint64_t                nr_stripes;
         unsigned                stripe_size_bits;
@@ -663,13 +664,9 @@ struct gc_stat {
  * CACHE_SET_STOPPING always gets set first when we're closing down a cache set;
  * we'll continue to run normally for awhile with CACHE_SET_STOPPING set (i.e.
  * flushing dirty data).
- *
- * CACHE_SET_STOPPING_2 gets set at the last phase, when it's time to shut down
- * the allocation thread.
  */
 #define CACHE_SET_UNREGISTERING         0
 #define CACHE_SET_STOPPING              1
-#define CACHE_SET_STOPPING_2            2
 
 struct cache_set {
         struct closure          cl;
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 15b58239c683..ee372884c405 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1410,8 +1410,10 @@ static void btree_gc_start(struct cache_set *c)
         for_each_cache(ca, c, i)
                 for_each_bucket(b, ca) {
                         b->gc_gen = b->gen;
-                        if (!atomic_read(&b->pin))
+                        if (!atomic_read(&b->pin)) {
                                 SET_GC_MARK(b, GC_MARK_RECLAIMABLE);
+                                SET_GC_SECTORS_USED(b, 0);
+                        }
                 }
 
         mutex_unlock(&c->bucket_lock);
diff --git a/drivers/md/bcache/closure.c b/drivers/md/bcache/closure.c
index bd05a9a8c7cf..9aba2017f0d1 100644
--- a/drivers/md/bcache/closure.c
+++ b/drivers/md/bcache/closure.c
@@ -66,16 +66,18 @@ static inline void closure_put_after_sub(struct closure *cl, int flags)
                 } else {
                         struct closure *parent = cl->parent;
                         struct closure_waitlist *wait = closure_waitlist(cl);
+                        closure_fn *destructor = cl->fn;
 
                         closure_debug_destroy(cl);
 
+                        smp_mb();
                         atomic_set(&cl->remaining, -1);
 
                         if (wait)
                                 closure_wake_up(wait);
 
-                        if (cl->fn)
-                                cl->fn(cl);
+                        if (destructor)
+                                destructor(cl);
 
                         if (parent)
                                 closure_put(parent);
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 4b250667bb7f..ba95ab84b2be 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -184,9 +184,14 @@ bsearch:
                 pr_debug("starting binary search, l %u r %u", l, r);
 
                 while (l + 1 < r) {
+                        seq = list_entry(list->prev, struct journal_replay,
+                                         list)->j.seq;
+
                         m = (l + r) >> 1;
+                        read_bucket(m);
 
-                        if (read_bucket(m))
+                        if (seq != list_entry(list->prev, struct journal_replay,
+                                              list)->j.seq)
                                 l = m;
                         else
                                 r = m;
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index b6e74d3c8faf..786a1a4f74d8 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -488,6 +488,12 @@ static void bch_insert_data_loop(struct closure *cl)
                 bch_queue_gc(op->c);
         }
 
+        /*
+         * Journal writes are marked REQ_FLUSH; if the original write was a
+         * flush, it'll wait on the journal write.
+         */
+        bio->bi_rw &= ~(REQ_FLUSH|REQ_FUA);
+
         do {
                 unsigned i;
                 struct bkey *k;
@@ -710,7 +716,7 @@ static struct search *search_alloc(struct bio *bio, struct bcache_device *d)
         s->task                 = current;
         s->orig_bio             = bio;
         s->write                = (bio->bi_rw & REQ_WRITE) != 0;
-        s->op.flush_journal     = (bio->bi_rw & REQ_FLUSH) != 0;
+        s->op.flush_journal     = (bio->bi_rw & (REQ_FLUSH|REQ_FUA)) != 0;
         s->op.skip              = (bio->bi_rw & REQ_DISCARD) != 0;
         s->recoverable          = 1;
         s->start_time           = jiffies;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index cff2d182dfb0..547c4c57b052 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -16,6 +16,7 @@
 #include <linux/buffer_head.h>
 #include <linux/debugfs.h>
 #include <linux/genhd.h>
+#include <linux/kthread.h>
 #include <linux/module.h>
 #include <linux/random.h>
 #include <linux/reboot.h>
@@ -706,7 +707,8 @@ static void bcache_device_detach(struct bcache_device *d)
                 atomic_set(&d->detaching, 0);
         }
 
-        bcache_device_unlink(d);
+        if (!d->flush_done)
+                bcache_device_unlink(d);
 
         d->c->devices[d->id] = NULL;
         closure_put(&d->c->caching);
@@ -806,6 +808,8 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
         set_bit(QUEUE_FLAG_NONROT,      &d->disk->queue->queue_flags);
         set_bit(QUEUE_FLAG_DISCARD,     &d->disk->queue->queue_flags);
 
+        blk_queue_flush(q, REQ_FLUSH|REQ_FUA);
+
         return 0;
 }
 
@@ -1053,6 +1057,14 @@ static void cached_dev_flush(struct closure *cl)
         struct cached_dev *dc = container_of(cl, struct cached_dev, disk.cl);
         struct bcache_device *d = &dc->disk;
 
+        mutex_lock(&bch_register_lock);
+        d->flush_done = 1;
+
+        if (d->c)
+                bcache_device_unlink(d);
+
+        mutex_unlock(&bch_register_lock);
+
         bch_cache_accounting_destroy(&dc->accounting);
         kobject_del(&d->kobj);
 
@@ -1318,11 +1330,9 @@ static void cache_set_free(struct closure *cl)
 static void cache_set_flush(struct closure *cl)
 {
         struct cache_set *c = container_of(cl, struct cache_set, caching);
+        struct cache *ca;
         struct btree *b;
-
-        /* Shut down allocator threads */
-        set_bit(CACHE_SET_STOPPING_2, &c->flags);
-        wake_up_allocators(c);
+        unsigned i;
 
         bch_cache_accounting_destroy(&c->accounting);
 
@@ -1337,24 +1347,32 @@ static void cache_set_flush(struct closure *cl)
                 if (btree_node_dirty(b))
                         bch_btree_node_write(b, NULL);
 
+        for_each_cache(ca, c, i)
+                if (ca->alloc_thread)
+                        kthread_stop(ca->alloc_thread);
+
         closure_return(cl);
 }
 
 static void __cache_set_unregister(struct closure *cl)
 {
         struct cache_set *c = container_of(cl, struct cache_set, caching);
-        struct cached_dev *dc, *t;
+        struct cached_dev *dc;
         size_t i;
 
         mutex_lock(&bch_register_lock);
 
-        if (test_bit(CACHE_SET_UNREGISTERING, &c->flags))
-                list_for_each_entry_safe(dc, t, &c->cached_devs, list)
-                        bch_cached_dev_detach(dc);
-
         for (i = 0; i < c->nr_uuids; i++)
-                if (c->devices[i] && UUID_FLASH_ONLY(&c->uuids[i]))
-                        bcache_device_stop(c->devices[i]);
+                if (c->devices[i]) {
+                        if (!UUID_FLASH_ONLY(&c->uuids[i]) &&
+                            test_bit(CACHE_SET_UNREGISTERING, &c->flags)) {
+                                dc = container_of(c->devices[i],
+                                                  struct cached_dev, disk);
+                                bch_cached_dev_detach(dc);
+                        } else {
+                                bcache_device_stop(c->devices[i]);
+                        }
+                }
 
         mutex_unlock(&bch_register_lock);
 
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index dd3f00a42729..12a2c2846f99 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -232,6 +232,8 @@ STORE(__cached_dev)
                         bch_uuid_write(dc->disk.c);
                 }
                 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
+                if (!env)
+                        return -ENOMEM;
                 add_uevent_var(env, "DRIVER=bcache");
                 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
                 add_uevent_var(env, "CACHED_LABEL=%s", buf);