Commit ff85f15f authored by Jacek Kalwas's avatar Jacek Kalwas Committed by Jim Harris
Browse files

bdev: fix return value of bdev_io_get_max_buf_len 



Fixed function is used to determine if it is possible to get iobuf
from the pool. To make sure that buf size alignment requirement is
satisifed value returned shall include alignment value but subtracted
by one.

e.g.
transaction size length = 64k
buffer alignment = 1 byte (no alignment requirement)
metadata length = 0

Without the fix the function returned 64k + 1, now it returns 64k
which is correct behavior and allows to proceed with further command
processing (if max buffer size limit is set to 64k only).

Signed-off-by: default avatarJacek Kalwas <jacek.kalwas@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/17513

 (master)

(cherry picked from commit 13a2c558)
Change-Id: I09104ad21b3652ba1aa5c3805a04b1c6549d04ac
Signed-off-by: default avatarKrzysztof Karas <krzysztof.karas@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/17706


Tested-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
parent 82466708

lib/bdev/bdev.c

+3 −1
Original line number Diff line number Diff line
@@ -1051,7 +1051,9 @@ bdev_io_get_max_buf_len(struct spdk_bdev_io *bdev_io, uint64_t len) 
	uint64_t md_len, alignment;



	md_len = spdk_bdev_is_md_separate(bdev) ? bdev_io->u.bdev.num_blocks * bdev->md_len : 0;

	alignment = spdk_bdev_get_buf_align(bdev);



	/* 1 byte alignment needs 0 byte of extra space, 64 bytes alignment needs 63 bytes of extra space, etc. */

	alignment = spdk_bdev_get_buf_align(bdev) - 1;



	return len + alignment + md_len;

}