Skip to content

Commit

Permalink
block: add async variant of blkdev_issue_zeroout
Browse files Browse the repository at this point in the history 
Similar to __blkdev_issue_discard this variant allows submitting
the final bio asynchronously and chaining multiple ranges
into a single completion.

Signed-off-by: Chaitanya Kulkarni <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
  • Loading branch information
@ChaitanayaKulkarni @axboe
ChaitanayaKulkarni authored and axboe committed Dec 1, 2016
1 parent b02d8aa commit e73c23f
Show file tree
Hide file tree
Showing 2 changed files with 84 additions and 34 deletions.
115 changes: 81 additions & 34 deletions block/blk-lib.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -137,24 +137,24 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
EXPORT_SYMBOL(blkdev_issue_discard);

/**
* blkdev_issue_write_same - queue a write same operation
* __blkdev_issue_write_same - generate number of bios with same page
* @bdev: target blockdev
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @page: page containing data to write
* @biop: pointer to anchor bio
*
* Description:
* Issue a write same request for the sectors in question.
* Generate and issue number of bios(REQ_OP_WRITE_SAME) with same page.
*/
int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask,
struct page *page)
static int __blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct page *page,
struct bio **biop)
{
struct request_queue *q = bdev_get_queue(bdev);
unsigned int max_write_same_sectors;
struct bio *bio = NULL;
int ret = 0;
struct bio *bio = *biop;
sector_t bs_mask;

if (!q)
Expand All @@ -164,6 +164,9 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
if ((sector | nr_sects) & bs_mask)
return -EINVAL;

if (!bdev_write_same(bdev))
return -EOPNOTSUPP;

/* Ensure that max_write_same_sectors doesn't overflow bi_size */
max_write_same_sectors = UINT_MAX >> 9;

Expand All @@ -185,39 +188,83 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
bio->bi_iter.bi_size = nr_sects << 9;
nr_sects = 0;
}
cond_resched();
}

if (bio) {
*biop = bio;
return 0;
}

/**
* blkdev_issue_write_same - queue a write same operation
* @bdev: target blockdev
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @page: page containing data
*
* Description:
* Issue a write same request for the sectors in question.
*/
int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask,
struct page *page)
{
struct bio *bio = NULL;
struct blk_plug plug;
int ret;

blk_start_plug(&plug);
ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask, page,
&bio);
if (ret == 0 && bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
return ret;
}
EXPORT_SYMBOL(blkdev_issue_write_same);

/**
* blkdev_issue_zeroout - generate number of zero filed write bios
* __blkdev_issue_zeroout - generate number of zero filed write bios
* @bdev: blockdev to issue
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @biop: pointer to anchor bio
* @discard: discard flag
*
* Description:
* Generate and issue number of bios with zerofiled pages.
*/

static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask)
int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
bool discard)
{
int ret;
struct bio *bio = NULL;
int bi_size = 0;
struct bio *bio = *biop;
unsigned int sz;
sector_t bs_mask;

bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
if ((sector | nr_sects) & bs_mask)
return -EINVAL;

if (discard) {
ret = __blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask,
BLKDEV_DISCARD_ZERO, biop);
if (ret == 0 || (ret && ret != -EOPNOTSUPP))
goto out;
}

ret = __blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask,
ZERO_PAGE(0), biop);
if (ret == 0 || (ret && ret != -EOPNOTSUPP))
goto out;

ret = 0;
while (nr_sects != 0) {
bio = next_bio(bio, min(nr_sects, (sector_t)BIO_MAX_PAGES),
gfp_mask);
Expand All @@ -227,21 +274,20 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,

while (nr_sects != 0) {
sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects);
ret = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0);
nr_sects -= ret >> 9;
sector += ret >> 9;
if (ret < (sz << 9))
bi_size = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0);
nr_sects -= bi_size >> 9;
sector += bi_size >> 9;
if (bi_size < (sz << 9))
break;
}
cond_resched();
}

if (bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
return ret;
}
return 0;
*biop = bio;
out:
return ret;
}
EXPORT_SYMBOL(__blkdev_issue_zeroout);

/**
* blkdev_issue_zeroout - zero-fill a block range
Expand All @@ -263,21 +309,22 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
* 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, bool discard)
{
if (discard) {
if (!blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask,
BLKDEV_DISCARD_ZERO))
return 0;
}
int ret;
struct bio *bio = NULL;
struct blk_plug plug;

if (bdev_write_same(bdev) &&
blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask,
ZERO_PAGE(0)) == 0)
return 0;
blk_start_plug(&plug);
ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask,
&bio, discard);
if (ret == 0 && bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);

return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask);
return ret;
}
EXPORT_SYMBOL(blkdev_issue_zeroout);
3 changes: 3 additions & 0 deletions include/linux/blkdev.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1269,6 +1269,9 @@ extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
struct bio **biop);
extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct page *page);
extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
bool discard);
extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, bool discard);
static inline int sb_issue_discard(struct super_block *sb, sector_t block,
Expand Down

0 comments on commit e73c23f

Please sign in to comment.