# \[PATCH 13/15\] block: use memcpy\_from\_bvec in \_\_blk\_queue\_bounce - From: Christoph Hellwig \ - Date: 2021-07-27 06:21:29 - List: linuxppc-dev - Page: https://ratatoskr.run/linuxppc-dev/2021/07/1459114 - Thread: https://ratatoskr.run/linux-mips/2021/07/1459073/t.md ```text Rewrite the actual bounce buffering loop in __blk_queue_bounce to that the memcpy_to_bvec helper can be used to perform the data copies. Signed-off-by: Christoph Hellwig Reviewed-by: Martin K. Petersen --- block/bounce.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/block/bounce.c b/block/bounce.c index 7e9e666c04dc..05fc7148489d 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -239,24 +239,19 @@ void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig) * because the 'bio' is single-page bvec. */ for (i = 0, to = bio->bi_io_vec; i < bio->bi_vcnt; to++, i++) { - struct page *page = to->bv_page; + struct page *bounce_page; - if (!PageHighMem(page)) + if (!PageHighMem(to->bv_page)) continue; - to->bv_page = mempool_alloc(&page_pool, GFP_NOIO); - inc_zone_page_state(to->bv_page, NR_BOUNCE); + bounce_page = mempool_alloc(&page_pool, GFP_NOIO); + inc_zone_page_state(bounce_page, NR_BOUNCE); if (rw == WRITE) { - char *vto, *vfrom; - - flush_dcache_page(page); - - vto = page_address(to->bv_page) + to->bv_offset; - vfrom = kmap_atomic(page) + to->bv_offset; - memcpy(vto, vfrom, to->bv_len); - kunmap_atomic(vfrom); + flush_dcache_page(to->bv_page); + memcpy_from_bvec(page_address(bounce_page), to); } + to->bv_page = bounce_page; } trace_block_bio_bounce(*bio_orig); -- 2.30.2 ```