[PATCH] dm: free minor after unlink gendisk

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / md / dm.c

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8c16359f8b0189c5a77d6eb19106ceb21231c0ce..745ca1f67b14a93db8e7c2802746d7963641aa7e 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -31,6 +31,7 @@ struct dm_io {
        int error;
        struct bio *bio;
        atomic_t io_count;
+       unsigned long start_time;
 };
 
 /*
@@ -244,6 +245,36 @@ static inline void free_tio(struct mapped_device *md, struct target_io *tio)
        mempool_free(tio, md->tio_pool);
 }
 
+static void start_io_acct(struct dm_io *io)
+{
+       struct mapped_device *md = io->md;
+
+       io->start_time = jiffies;
+
+       preempt_disable();
+       disk_round_stats(dm_disk(md));
+       preempt_enable();
+       dm_disk(md)->in_flight = atomic_inc_return(&md->pending);
+}
+
+static int end_io_acct(struct dm_io *io)
+{
+       struct mapped_device *md = io->md;
+       struct bio *bio = io->bio;
+       unsigned long duration = jiffies - io->start_time;
+       int pending;
+       int rw = bio_data_dir(bio);
+
+       preempt_disable();
+       disk_round_stats(dm_disk(md));
+       preempt_enable();
+       dm_disk(md)->in_flight = pending = atomic_dec_return(&md->pending);
+
+       disk_stat_add(dm_disk(md), ticks[rw], duration);
+
+       return !pending;
+}
+
 /*
  * Add the bio to the list of deferred io.
  */
@@ -299,7 +330,7 @@ static void dec_pending(struct dm_io *io, int error)
                io->error = error;
 
        if (atomic_dec_and_test(&io->io_count)) {
-               if (atomic_dec_and_test(&io->md->pending))
+               if (end_io_acct(io))
                        /* nudge anyone waiting on suspend queue */
                        wake_up(&io->md->wait);
 
@@ -554,7 +585,7 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
        ci.sector_count = bio_sectors(bio);
        ci.idx = bio->bi_idx;
 
-       atomic_inc(&md->pending);
+       start_io_acct(ci.io);
        while (ci.sector_count)
                __clone_and_map(&ci);
 
@@ -573,10 +604,14 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
 static int dm_request(request_queue_t *q, struct bio *bio)
 {
        int r;
+       int rw = bio_data_dir(bio);
        struct mapped_device *md = q->queuedata;
 
        down_read(&md->io_lock);
 
+       disk_stat_inc(dm_disk(md), ios[rw]);
+       disk_stat_add(dm_disk(md), sectors[rw], bio_sectors(bio));
+
        /*
         * If we're suspended we have to queue
         * this io for later.
@@ -814,10 +849,16 @@ static struct mapped_device *alloc_dev(unsigned int minor, int persistent)
 
 static void free_dev(struct mapped_device *md)
 {
-       free_minor(md->disk->first_minor);
+       unsigned int minor = md->disk->first_minor;
+
+       if (md->suspended_bdev) {
+               thaw_bdev(md->suspended_bdev, NULL);
+               bdput(md->suspended_bdev);
+       }
        mempool_destroy(md->tio_pool);
        mempool_destroy(md->io_pool);
        del_gendisk(md->disk);
+       free_minor(minor);
        put_disk(md->disk);
        blk_put_queue(md->queue);
        kfree(md);