BUG_ON() Conversion in md/dm-hw-handler.c

[powerpc.git] / drivers / md / dm.c

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8c16359..8c82373 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -17,6 +17,7 @@
 #include <linux/mempool.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
+#include <linux/blktrace_api.h>
 
 static const char *_name = DM_NAME;
 
@@ -31,6 +32,7 @@ struct dm_io {
        int error;
        struct bio *bio;
        atomic_t io_count;
+       unsigned long start_time;
 };
 
 /*
@@ -244,6 +246,36 @@ 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.
  */
@@ -299,10 +331,12 @@ 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);
 
+               blk_add_trace_bio(io->md->queue, io->bio, BLK_TA_COMPLETE);
+
                bio_endio(io->bio, io->bio->bi_size, io->error);
                free_io(io->md, io);
        }
@@ -361,6 +395,7 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
                      struct target_io *tio)
 {
        int r;
+       sector_t sector;
 
        /*
         * Sanity checks.
@@ -376,10 +411,17 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
         * this io.
         */
        atomic_inc(&tio->io->io_count);
+       sector = clone->bi_sector;
        r = ti->type->map(ti, clone, &tio->info);
-       if (r > 0)
+       if (r > 0) {
                /* the bio has been remapped so dispatch it */
+
+               blk_add_trace_remap(bdev_get_queue(clone->bi_bdev), clone, 
+                                   tio->io->bio->bi_bdev->bd_dev, sector, 
+                                   clone->bi_sector);
+
                generic_make_request(clone);
+       }
 
        else if (r < 0) {
                /* error the io and bail out */
@@ -502,30 +544,35 @@ static void __clone_and_map(struct clone_info *ci)
 
        } else {
                /*
-                * Create two copy bios to deal with io that has
-                * been split across a target.
+                * Handle a bvec that must be split between two or more targets.
                 */
                struct bio_vec *bv = bio->bi_io_vec + ci->idx;
+               sector_t remaining = to_sector(bv->bv_len);
+               unsigned int offset = 0;
 
-               clone = split_bvec(bio, ci->sector, ci->idx,
-                                  bv->bv_offset, max);
-               __map_bio(ti, clone, tio);
+               do {
+                       if (offset) {
+                               ti = dm_table_find_target(ci->map, ci->sector);
+                               max = max_io_len(ci->md, ci->sector, ti);
 
-               ci->sector += max;
-               ci->sector_count -= max;
-               ti = dm_table_find_target(ci->map, ci->sector);
-
-               len = to_sector(bv->bv_len) - max;
-               clone = split_bvec(bio, ci->sector, ci->idx,
-                                  bv->bv_offset + to_bytes(max), len);
-               tio = alloc_tio(ci->md);
-               tio->io = ci->io;
-               tio->ti = ti;
-               memset(&tio->info, 0, sizeof(tio->info));
-               __map_bio(ti, clone, tio);
+                               tio = alloc_tio(ci->md);
+                               tio->io = ci->io;
+                               tio->ti = ti;
+                               memset(&tio->info, 0, sizeof(tio->info));
+                       }
+
+                       len = min(remaining, max);
+
+                       clone = split_bvec(bio, ci->sector, ci->idx,
+                                          bv->bv_offset + offset, len);
+
+                       __map_bio(ti, clone, tio);
+
+                       ci->sector += len;
+                       ci->sector_count -= len;
+                       offset += to_bytes(len);
+               } while (remaining -= len);
 
-               ci->sector += len;
-               ci->sector_count -= len;
                ci->idx++;
        }
 }
@@ -554,7 +601,7 @@ 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 +620,14 @@ 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.
@@ -805,7 +856,7 @@ static struct mapped_device *alloc_dev(unsigned int minor, int persistent)
  bad3:
        mempool_destroy(md->io_pool);
  bad2:
-       blk_put_queue(md->queue);
+       blk_cleanup_queue(md->queue);
        free_minor(minor);
  bad1:
        kfree(md);
@@ -814,12 +865,18 @@ 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);
+       blk_cleanup_queue(md->queue);
        kfree(md);
 }