1 files changed, 19 insertions, 8 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 23e76fe0d359..724efc63904d 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -47,6 +47,7 @@ struct dm_io {
         atomic_t io_count;
         struct bio *bio;
         unsigned long start_time;
+        spinlock_t endio_lock;
 };
 
 /*
@@ -130,7 +131,7 @@ struct mapped_device {
         /*
          * A list of ios that arrived while we were suspended.
          */
-        atomic_t pending;
+        atomic_t pending[2];
         wait_queue_head_t wait;
         struct work_struct work;
         struct bio_list deferred;
@@ -453,13 +454,14 @@ static void start_io_acct(struct dm_io *io)
 {
         struct mapped_device *md = io->md;
         int cpu;
+        int rw = bio_data_dir(io->bio);
 
         io->start_time = jiffies;
 
         cpu = part_stat_lock();
         part_round_stats(cpu, &dm_disk(md)->part0);
         part_stat_unlock();
-        dm_disk(md)->part0.in_flight = atomic_inc_return(&md->pending);
+        dm_disk(md)->part0.in_flight[rw] = atomic_inc_return(&md->pending[rw]);
 }
 
 static void end_io_acct(struct dm_io *io)
@@ -479,8 +481,9 @@ static void end_io_acct(struct dm_io *io)
          * After this is decremented the bio must not be touched if it is
          * a barrier.
          */
-        dm_disk(md)->part0.in_flight = pending =
-                atomic_dec_return(&md->pending);
+        dm_disk(md)->part0.in_flight[rw] = pending =
+                atomic_dec_return(&md->pending[rw]);
+        pending += atomic_read(&md->pending[rw^0x1]);
 
         /* nudge anyone waiting on suspend queue */
         if (!pending)
@@ -576,8 +579,12 @@ static void dec_pending(struct dm_io *io, int error)
         struct mapped_device *md = io->md;
 
         /* Push-back supersedes any I/O errors */
-        if (error && !(io->error > 0 && __noflush_suspending(md)))
-                io->error = error;
+        if (unlikely(error)) {
+                spin_lock_irqsave(&io->endio_lock, flags);
+                if (!(io->error > 0 && __noflush_suspending(md)))
+                        io->error = error;
+                spin_unlock_irqrestore(&io->endio_lock, flags);
+        }
 
         if (atomic_dec_and_test(&io->io_count)) {
                 if (io->error == DM_ENDIO_REQUEUE) {
@@ -1224,6 +1231,7 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
         atomic_set(&ci.io->io_count, 1);
         ci.io->bio = bio;
         ci.io->md = md;
+        spin_lock_init(&ci.io->endio_lock);
         ci.sector = bio->bi_sector;
         ci.sector_count = bio_sectors(bio);
         if (unlikely(bio_empty_barrier(bio)))
@@ -1785,7 +1793,8 @@ static struct mapped_device *alloc_dev(int minor)
         if (!md->disk)
                 goto bad_disk;
 
-        atomic_set(&md->pending, 0);
+        atomic_set(&md->pending[0], 0);
+        atomic_set(&md->pending[1], 0);
         init_waitqueue_head(&md->wait);
         INIT_WORK(&md->work, dm_wq_work);
         init_waitqueue_head(&md->eventq);
@@ -1819,6 +1828,7 @@ static struct mapped_device *alloc_dev(int minor)
 bad_bdev:
         destroy_workqueue(md->wq);
 bad_thread:
+        del_gendisk(md->disk);
         put_disk(md->disk);
 bad_disk:
         blk_cleanup_queue(md->queue);
@@ -2088,7 +2098,8 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
                                 break;
                         }
                         spin_unlock_irqrestore(q->queue_lock, flags);
-                } else if (!atomic_read(&md->pending))
+                } else if (!atomic_read(&md->pending[0]) &&
+                                        !atomic_read(&md->pending[1]))
                         break;
 
                 if (interruptible == TASK_INTERRUPTIBLE &&