[PATCH 08/10] drbd: use bvec_kmap_local in drbd_csum_bio

Christoph Hellwig
2022-02-22T15:52:53Z

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/block/drbd/drbd_worker.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index a5e04b38006b6..1b48c8172a077 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -326,9 +326,9 @@ void drbd_csum_bio(struct crypto_shash *tfm, struct bio *bio, void *digest)
bio_for_each_segment(bvec, bio, iter) {
u8 *src;

- src = kmap_atomic(bvec.bv_page);
- crypto_shash_update(desc, src + bvec.bv_offset, bvec.bv_len);
- kunmap_atomic(src);
+ src = bvec_kmap_local(&bvec);
+ crypto_shash_update(desc, src, bvec.bv_len);
+ kunmap_local(src);

/* REQ_OP_WRITE_SAME has only one segment,
* checksum the payload only once. */
--
2.30.2