[PATCH 16/18] block: use memcpy_from_bvec in __blk_queue_bounce
From: Christoph Hellwig <hch@lst.de>
Date: 2021-06-15 13:32:45
Also in:
ceph-devel, dm-devel, linux-block, linux-mips, linuxppc-dev, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
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 <hch@lst.de> --- 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