On 6/10/22 12:58, Keith Busch wrote:
From: Keith Busch <kbusch@xxxxxxxxxx>
Individual bv_len's may not be a sector size.
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
---
block/bounce.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/block/bounce.c b/block/bounce.c
index 8f7b6fe3b4db..fbadf179601f 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -205,19 +205,26 @@ void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig)
int rw = bio_data_dir(*bio_orig);
struct bio_vec *to, from;
struct bvec_iter iter;
- unsigned i = 0;
+ unsigned i = 0, bytes = 0;
bool bounce = false;
- int sectors = 0;
+ int sectors;
bio_for_each_segment(from, *bio_orig, iter) {
if (i++ < BIO_MAX_VECS)
- sectors += from.bv_len >> 9;
+ bytes += from.bv_len;
if (PageHighMem(from.bv_page))
bounce = true;
}
if (!bounce)
return;
+ /*
+ * Individual bvecs might not be logical block aligned. Round down
+ * the split size so that each bio is properly block size aligned,
+ * even if we do not use the full hardware limits.
+ */
+ sectors = ALIGN_DOWN(bytes, queue_logical_block_size(q)) >>
+ SECTOR_SHIFT;
if (sectors < bio_sectors(*bio_orig)) {
bio = bio_split(*bio_orig, sectors, GFP_NOIO, &bounce_bio_split);
bio_chain(bio, *bio_orig);
Do I see correctly that there are two changes in this patch: counting
bytes instead of sectors and also splitting at logical block boundaries
instead of a 512-byte boundary? Should this patch perhaps be split?
Thanks,
Bart.
