[PATCH 13/18] block: rewrite bio_copy_data_iter to use bvec_kmap_local and memcpy_to_bvec
From: Christoph Hellwig <hch@lst.de>
Date: 2021-06-15 13:31:43
Also in:
ceph-devel, dm-devel, linux-arch, linux-block, linuxppc-dev, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
Use the proper helpers instead of open coding the copy. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/bio.c | 28 ++++++++-------------------- 1 file changed, 8 insertions(+), 20 deletions(-)
diff --git a/block/bio.c b/block/bio.c
index 1d7abdb83a39..c14d2e66c084 100644
--- a/block/bio.c
+++ b/block/bio.c@@ -1186,27 +1186,15 @@ EXPORT_SYMBOL(bio_advance); void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, struct bio *src, struct bvec_iter *src_iter) { - struct bio_vec src_bv, dst_bv; - void *src_p, *dst_p; - unsigned bytes; - while (src_iter->bi_size && dst_iter->bi_size) { - src_bv = bio_iter_iovec(src, *src_iter); - dst_bv = bio_iter_iovec(dst, *dst_iter); - - bytes = min(src_bv.bv_len, dst_bv.bv_len); - - src_p = kmap_atomic(src_bv.bv_page); - dst_p = kmap_atomic(dst_bv.bv_page); - - memcpy(dst_p + dst_bv.bv_offset, - src_p + src_bv.bv_offset, - bytes); - - kunmap_atomic(dst_p); - kunmap_atomic(src_p); - - flush_dcache_page(dst_bv.bv_page); + struct bio_vec src_bv = bio_iter_iovec(src, *src_iter); + struct bio_vec dst_bv = bio_iter_iovec(dst, *dst_iter); + unsigned int bytes = min(src_bv.bv_len, dst_bv.bv_len); + void *src_buf; + + src_buf = bvec_kmap_local(&src_bv); + memcpy_to_bvec(&dst_bv, src_buf); + kunmap_local(src_buf); bio_advance_iter_single(src, src_iter, bytes); bio_advance_iter_single(dst, dst_iter, bytes);
--
2.30.2