dm thin: use __blkdev_issue_discard for async discard support

With commit 38f2525533 ("block: add __blkdev_issue_discard") DM thinp
no longer needs to carry its own async discard method.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Mike Snitzer 2016-05-02 20:16:21 -04:00
parent 13e4f8a695
commit 3dba53a958

View file

@ -322,56 +322,6 @@ struct thin_c {
/*----------------------------------------------------------------*/
/**
* __blkdev_issue_discard_async - queue a discard with async completion
* @bdev: blockdev to issue discard for
* @sector: start sector
* @nr_sects: number of sectors to discard
* @gfp_mask: memory allocation flags (for bio_alloc)
* @flags: BLKDEV_IFL_* flags to control behaviour
* @parent_bio: parent discard bio that all sub discards get chained to
*
* Description:
* Asynchronously issue a discard request for the sectors in question.
*/
static int __blkdev_issue_discard_async(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned long flags,
struct bio *parent_bio)
{
struct request_queue *q = bdev_get_queue(bdev);
int type = REQ_WRITE | REQ_DISCARD;
struct bio *bio;
if (!q || !nr_sects)
return -ENXIO;
if (!blk_queue_discard(q))
return -EOPNOTSUPP;
if (flags & BLKDEV_DISCARD_SECURE) {
if (!blk_queue_secdiscard(q))
return -EOPNOTSUPP;
type |= REQ_SECURE;
}
/*
* Required bio_put occurs in bio_endio thanks to bio_chain below
*/
bio = bio_alloc(gfp_mask, 1);
if (!bio)
return -ENOMEM;
bio_chain(bio, parent_bio);
bio->bi_iter.bi_sector = sector;
bio->bi_bdev = bdev;
bio->bi_iter.bi_size = nr_sects << 9;
submit_bio(type, bio);
return 0;
}
static bool block_size_is_power_of_two(struct pool *pool)
{
return pool->sectors_per_block_shift >= 0;
@ -387,11 +337,23 @@ static sector_t block_to_sectors(struct pool *pool, dm_block_t b)
static int issue_discard(struct thin_c *tc, dm_block_t data_b, dm_block_t data_e,
struct bio *parent_bio)
{
int type = REQ_WRITE | REQ_DISCARD;
sector_t s = block_to_sectors(tc->pool, data_b);
sector_t len = block_to_sectors(tc->pool, data_e - data_b);
struct bio *bio = NULL;
struct blk_plug plug;
int ret;
return __blkdev_issue_discard_async(tc->pool_dev->bdev, s, len,
GFP_NOWAIT, 0, parent_bio);
blk_start_plug(&plug);
ret = __blkdev_issue_discard(tc->pool_dev->bdev, s, len,
GFP_NOWAIT, type, &bio);
if (!ret && bio) {
bio_chain(bio, parent_bio);
submit_bio(type, bio);
}
blk_finish_plug(&plug);
return ret;
}
/*----------------------------------------------------------------*/
@ -1543,11 +1505,11 @@ static void break_up_discard_bio(struct thin_c *tc, dm_block_t begin, dm_block_t
/*
* The parent bio must not complete before sub discard bios are
* chained to it (see __blkdev_issue_discard_async's bio_chain)!
* chained to it (see issue_discard's bio_chain)!
*
* This per-mapping bi_remaining increment is paired with
* the implicit decrement that occurs via bio_endio() in
* process_prepared_discard_{passdown,no_passdown}.
* process_prepared_discard_passdown().
*/
bio_inc_remaining(bio);
if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list))