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block: refacto blkdev_issue_zeroout

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Split out two well-defined helpers for hardware supported Write Zeroes
and manually writing zeroes using the Write command.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240701165219.1571322-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2024-07-01 18:51:18 +02:00 committed by Jens Axboe
parent f6eacb2654
commit 99800ced26
1 changed files with 55 additions and 39 deletions
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94
block/blk-lib.c
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@ -135,6 +135,32 @@ static void __blkdev_issue_write_zeroes(struct block_device *bdev,
*biop = bio;
}
static int blkdev_issue_write_zeroes(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp, unsigned flags)
{
struct bio *bio = NULL;
struct blk_plug plug;
int ret = 0;
blk_start_plug(&plug);
__blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp, &bio, flags);
if (bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
/*
* For some devices there is no non-destructive way to verify whether
* WRITE ZEROES is actually supported. These will clear the capability
* on an I/O error, in which case we'll turn any error into
* "not supported" here.
*/
if (ret && !bdev_write_zeroes_sectors(bdev))
return -EOPNOTSUPP;
return ret;
}
/*
* Convert a number of 512B sectors to a number of pages.
* The result is limited to a number of pages that can fit into a BIO.
@ -175,6 +201,27 @@ static void __blkdev_issue_zero_pages(struct block_device *bdev,
*biop = bio;
}
static int blkdev_issue_zero_pages(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp, unsigned flags)
{
struct bio *bio = NULL;
struct blk_plug plug;
int ret = 0;
if (flags & BLKDEV_ZERO_NOFALLBACK)
return -EOPNOTSUPP;
blk_start_plug(&plug);
__blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp, &bio);
if (bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
return ret;
}
/**
* __blkdev_issue_zeroout - generate number of zero filed write bios
* @bdev: blockdev to issue
@ -230,52 +277,21 @@ EXPORT_SYMBOL(__blkdev_issue_zeroout);
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
{
int ret = 0;
sector_t bs_mask;
struct bio *bio;
struct blk_plug plug;
bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
int ret;
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
if ((sector | nr_sects) & bs_mask)
if ((sector | nr_sects) & ((bdev_logical_block_size(bdev) >> 9) - 1))
return -EINVAL;
if (bdev_read_only(bdev))
return -EPERM;
if ((flags & BLKDEV_ZERO_NOFALLBACK) && !try_write_zeroes)
return -EOPNOTSUPP;
retry:
bio = NULL;
blk_start_plug(&plug);
if (try_write_zeroes) {
__blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
&bio, flags);
} else {
__blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
&bio);
}
if (bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
if (ret && try_write_zeroes) {
if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
try_write_zeroes = false;
goto retry;
}
if (!bdev_write_zeroes_sectors(bdev)) {
/*
* Zeroing offload support was indicated, but the
* device reported ILLEGAL REQUEST (for some devices
* there is no non-destructive way to verify whether
* WRITE ZEROES is actually supported).
*/
ret = -EOPNOTSUPP;
}
if (bdev_write_zeroes_sectors(bdev)) {
ret = blkdev_issue_write_zeroes(bdev, sector, nr_sects,
gfp_mask, flags);
if (!ret)
return ret;
}
return ret;
return blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask, flags);
}
EXPORT_SYMBOL(blkdev_issue_zeroout);