Commit 2dcaa385 authored by Shuhei Matsumoto's avatar Shuhei Matsumoto Committed by Jim Harris
Browse files

bdev: Fix max write_zeroes calculation for fallback case 



ZERO_BUFFER_SIZE is in bytes but it is easier to calculate max
write_zeroes in blocks first and then get the minimum between max
write_zeroes in blocks and remaining_num_blocks rather than converting
remaining_num_blocks to num_bytes. This is helpful to store the result
into bdev->max_write_zeroes for fallback case.

We have one small fix in this patch. As we recently fixed
bdev_io_get_max_buf_len(), to get aligned length,
spdk_bdev_get_buf_align() - 1 is correct.

Signed-off-by: default avatarShuhei Matsumoto <smatsumoto@nvidia.com>
Change-Id: I104bc837c9eee1303664bfdb3559b0e840d6f0e5
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/17910


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarAleksey Marchuk <alexeymar@nvidia.com>
parent 0c1df53e

lib/bdev/bdev.c

+8 −6
Original line number Diff line number Diff line
@@ -8583,15 +8583,17 @@ static void 
bdev_write_zero_buffer_next(void *_bdev_io)

{

	struct spdk_bdev_io *bdev_io = _bdev_io;

	uint64_t num_bytes, num_blocks;

	uint64_t aligned_length, max_write_zeroes_blocks;

	uint64_t num_blocks;

	void *md_buf = NULL;

	int rc;



	num_bytes = spdk_min(_bdev_get_block_size_with_md(bdev_io->bdev) *

			     bdev_io->u.bdev.split_remaining_num_blocks,

			     ZERO_BUFFER_SIZE);

	num_blocks = num_bytes / _bdev_get_block_size_with_md(bdev_io->bdev);

	num_blocks -= num_blocks % bdev_io->bdev->write_unit_size;

	aligned_length = ZERO_BUFFER_SIZE - (spdk_bdev_get_buf_align(bdev_io->bdev) - 1);

	max_write_zeroes_blocks = aligned_length / _bdev_get_block_size_with_md(bdev_io->bdev);

	max_write_zeroes_blocks -= max_write_zeroes_blocks % bdev_io->bdev->write_unit_size;



	num_blocks = spdk_min(bdev_io->u.bdev.split_remaining_num_blocks,

			      max_write_zeroes_blocks);



	if (spdk_bdev_is_md_separate(bdev_io->bdev)) {

		md_buf = (char *)g_bdev_mgr.zero_buffer +