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@xxxxxx>
Reviewed-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
---
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
