Commit f8b679a0 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: rewrite bio_copy_data_iter to use bvec_kmap_local and memcpy_to_bvec 



Use the proper helpers instead of open coding the copy.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210727055646.118787-11-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent bda135d9

block/bio.c

+8 −20
Original line number Diff line number Diff line
@@ -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);