| Message ID | 20220526010613.4016118-8-kbusch@fb.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | direct io dma alignment | expand |
On 2022/05/26 10:06, Keith Busch wrote: > From: Keith Busch <kbusch@kernel.org> > > Individual bv_len's may not be a sector size. > > Signed-off-by: Keith Busch <kbusch@kernel.org> > --- > v3->v4: > > Use sector shift > > Add comment explaing the ALIGN_DOWN > > Use unsigned int type for counting bytes > > block/bounce.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/block/bounce.c b/block/bounce.c > index 8f7b6fe3b4db..f6ae21ec2a70 100644 > --- a/block/bounce.c > +++ b/block/bounce.c > @@ -205,19 +205,25 @@ 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; > > + /* > + * If the original has more than BIO_MAX_VECS biovecs, the total bytes > + * may not be block size aligned. Align down to ensure both sides of > + * the split bio are appropriately sized. > + */ > + 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); Looks good. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
On Wed, May 25, 2022 at 06:06:11PM -0700, Keith Busch wrote: > From: Keith Busch <kbusch@kernel.org> > > Individual bv_len's may not be a sector size. > > Signed-off-by: Keith Busch <kbusch@kernel.org> > --- > v3->v4: > > Use sector shift > > Add comment explaing the ALIGN_DOWN > > Use unsigned int type for counting bytes > > block/bounce.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/block/bounce.c b/block/bounce.c > index 8f7b6fe3b4db..f6ae21ec2a70 100644 > --- a/block/bounce.c > +++ b/block/bounce.c > @@ -205,19 +205,25 @@ 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; > > + /* > + * If the original has more than BIO_MAX_VECS biovecs, the total bytes > + * may not be block size aligned. Align down to ensure both sides of > + * the split bio are appropriately sized. > + */ > + 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); > -- > 2.30.2 > Looks good, Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
On Wed, May 25, 2022 at 06:06:11PM -0700, Keith Busch wrote: > + /* > + * If the original has more than BIO_MAX_VECS biovecs, the total bytes > + * may not be block size aligned. Align down to ensure both sides of > + * the split bio are appropriately sized. > + */ Same comment on the comment as fo the previous patch. > + sectors = ALIGN_DOWN(bytes, queue_logical_block_size(q)) >> SECTOR_SHIFT; Overly long line here.
diff --git a/block/bounce.c b/block/bounce.c index 8f7b6fe3b4db..f6ae21ec2a70 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -205,19 +205,25 @@ 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; + /* + * If the original has more than BIO_MAX_VECS biovecs, the total bytes + * may not be block size aligned. Align down to ensure both sides of + * the split bio are appropriately sized. + */ + 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);