diff options
Diffstat (limited to 'block/blk-lib.c')
| -rw-r--r-- | block/blk-lib.c | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/block/blk-lib.c b/block/blk-lib.c index 8411be3c19d3..7688ee3f5d72 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -283,24 +283,34 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, * @sector: start sector * @nr_sects: number of sectors to write * @gfp_mask: memory allocation flags (for bio_alloc) + * @discard: whether to discard the block range * * Description: - * Generate and issue number of bios with zerofiled pages. + * Zero-fill a block range. If the discard flag is set and the block + * device guarantees that subsequent READ operations to the block range + * in question will return zeroes, the blocks will be discarded. Should + * the discard request fail, if the discard flag is not set, or if + * discard_zeroes_data is not supported, this function will resort to + * zeroing the blocks manually, thus provisioning (allocating, + * anchoring) them. If the block device supports the WRITE SAME command + * blkdev_issue_zeroout() will use it to optimize the process of + * clearing the block range. Otherwise the zeroing will be performed + * using regular WRITE calls. */ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, - sector_t nr_sects, gfp_t gfp_mask) + sector_t nr_sects, gfp_t gfp_mask, bool discard) { - if (bdev_write_same(bdev)) { - unsigned char bdn[BDEVNAME_SIZE]; + struct request_queue *q = bdev_get_queue(bdev); - if (!blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, - ZERO_PAGE(0))) - return 0; + if (discard && blk_queue_discard(q) && q->limits.discard_zeroes_data && + blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, 0) == 0) + return 0; - bdevname(bdev, bdn); - pr_err("%s: WRITE SAME failed. Manually zeroing.\n", bdn); - } + if (bdev_write_same(bdev) && + blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, + ZERO_PAGE(0)) == 0) + return 0; return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask); } |