Re: [PATCH 09/10] drbd: use bvec_kmap_local in recv_dless_read

Ira Weiny
2022-03-01T04:10:06Z

On Tue, Feb 22, 2022 at 04:51:55PM +0100, Christoph Hellwig wrote:
> 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>

Reviewed-by: Ira Weiny <ira.weiny@intel.com>

> ---
> drivers/block/drbd/drbd_receiver.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
> index 04e3ec12d8b49..fa00cf2ea9529 100644
> --- a/drivers/block/drbd/drbd_receiver.c
> +++ b/drivers/block/drbd/drbd_receiver.c
> @@ -2017,10 +2017,10 @@ static int recv_dless_read(struct drbd_peer_device *peer_device, struct drbd_req
> D_ASSERT(peer_device->device, sector == bio->bi_iter.bi_sector);
>
> bio_for_each_segment(bvec, bio, iter) {
> - void *mapped = kmap(bvec.bv_page) + bvec.bv_offset;
> + void *mapped = bvec_kmap_local(&bvec);
> expect = min_t(int, data_size, bvec.bv_len);
> err = drbd_recv_all_warn(peer_device->connection, mapped, expect);
> - kunmap(bvec.bv_page);
> + kunmap_local(mapped);
> if (err)
> return err;
> data_size -= expect;
> --
> 2.30.2
>
>