diff options
| -rw-r--r-- | block/blk-lib.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/block/blk-lib.c b/block/blk-lib.c index e8caecd71688..3fe0aec90597 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -261,6 +261,19 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev, return 0; } +/* + * 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. + * Also make sure that the result is always at least 1 (page) for the cases + * where nr_sects is lower than the number of sectors in a page. + */ +static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects) +{ + sector_t bytes = (nr_sects << 9) + PAGE_SIZE - 1; + + return min(bytes >> PAGE_SHIFT, (sector_t)BIO_MAX_PAGES); +} + /** * __blkdev_issue_zeroout - generate number of zero filed write bios * @bdev: blockdev to issue @@ -307,18 +320,18 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, ret = 0; while (nr_sects != 0) { - bio = next_bio(bio, min(nr_sects, (sector_t)BIO_MAX_PAGES), - gfp_mask); + bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects), + gfp_mask); bio->bi_iter.bi_sector = sector; bio->bi_bdev = bdev; bio_set_op_attrs(bio, REQ_OP_WRITE, 0); while (nr_sects != 0) { - sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects); - bi_size = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0); + sz = min((sector_t) PAGE_SIZE, nr_sects << 9); + bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0); nr_sects -= bi_size >> 9; sector += bi_size >> 9; - if (bi_size < (sz << 9)) + if (bi_size < sz) break; } cond_resched(); |