brd: pass a bvec pointer to brd_do_bvec

Pass the bvec to brd_do_bvec instead of marshalling the information into
individual arguments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250428141014.2360063-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 292f127cae0abe9f5f8dc8165946ddff9e60f99b..c8974bc545fbe2db50a5ddcecfe28cffbccba893 100644 (file)
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -189,12 +189,10 @@ static void copy_from_brd(void *dst, struct brd_device *brd,
 /*
  * Process a single bvec of a bio.
  */
-static int brd_do_bvec(struct brd_device *brd, struct page *page,
-                       unsigned int len, unsigned int off, blk_opf_t opf,
-                       sector_t sector)
+static int brd_rw_bvec(struct brd_device *brd, struct bio_vec *bv,
+               blk_opf_t opf, sector_t sector)
 {
        void *mem;
-       int err = 0;
 
        if (op_is_write(opf)) {
                /*
@@ -202,24 +200,23 @@ static int brd_do_bvec(struct brd_device *brd, struct page *page,
                 * block or filesystem layers from page reclaim.
                 */
                gfp_t gfp = opf & REQ_NOWAIT ? GFP_NOWAIT : GFP_NOIO;
+               int err;
 
-               err = copy_to_brd_setup(brd, sector, len, gfp);
+               err = copy_to_brd_setup(brd, sector, bv->bv_len, gfp);
                if (err)
-                       goto out;
+                       return err;
        }
 
-       mem = kmap_atomic(page);
+       mem = kmap_atomic(bv->bv_page);
        if (!op_is_write(opf)) {
-               copy_from_brd(mem + off, brd, sector, len);
-               flush_dcache_page(page);
+               copy_from_brd(mem + bv->bv_offset, brd, sector, bv->bv_len);
+               flush_dcache_page(bv->bv_page);
        } else {
-               flush_dcache_page(page);
-               copy_to_brd(brd, mem + off, sector, len);
+               flush_dcache_page(bv->bv_page);
+               copy_to_brd(brd, mem + bv->bv_offset, sector, bv->bv_len);
        }
        kunmap_atomic(mem);
-
-out:
-       return err;
+       return 0;
 }
 
 static void brd_do_discard(struct brd_device *brd, sector_t sector, u32 size)
@@ -255,15 +252,9 @@ static void brd_submit_bio(struct bio *bio)
        }
 
        bio_for_each_segment(bvec, bio, iter) {
-               unsigned int len = bvec.bv_len;
                int err;
 
-               /* Don't support un-aligned buffer */
-               WARN_ON_ONCE((bvec.bv_offset & (SECTOR_SIZE - 1)) ||
-                               (len & (SECTOR_SIZE - 1)));
-
-               err = brd_do_bvec(brd, bvec.bv_page, len, bvec.bv_offset,
-                                 bio->bi_opf, sector);
+               err = brd_rw_bvec(brd, &bvec, bio->bi_opf, sector);
                if (err) {
                        if (err == -ENOMEM && bio->bi_opf & REQ_NOWAIT) {
                                bio_wouldblock_error(bio);
@@ -272,7 +263,7 @@ static void brd_submit_bio(struct bio *bio)
                        bio_io_error(bio);
                        return;
                }
-               sector += len >> SECTOR_SHIFT;
+               sector += bvec.bv_len >> SECTOR_SHIFT;
        }
 
        bio_endio(bio);