On 2016/12/27 下午11:56, Ming Lei wrote: > The incoming bio may be too big to be cloned into > one singlepage bvecs bio, so split the bio and > check the splitted bio one by one. > > Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx> > --- > drivers/md/bcache/debug.c | 24 ++++++++++++++++++++++-- > 1 file changed, 22 insertions(+), 2 deletions(-) > > diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c > index 48d03e8b3385..18b2d2d138e3 100644 > --- a/drivers/md/bcache/debug.c > +++ b/drivers/md/bcache/debug.c > @@ -103,7 +103,7 @@ void bch_btree_verify(struct btree *b) > up(&b->io_mutex); > } > > -void bch_data_verify(struct cached_dev *dc, struct bio *bio) > +static void __bch_data_verify(struct cached_dev *dc, struct bio *bio) > { > char name[BDEVNAME_SIZE]; > struct bio *check; > @@ -116,7 +116,7 @@ void bch_data_verify(struct cached_dev *dc, struct bio *bio) > * in the new cloned bio because each single page need > * to assign to each bvec of the new bio. > */ > - check = bio_clone(bio, GFP_NOIO); > + check = bio_clone_sp(bio, GFP_NOIO); > if (!check) > return; > check->bi_opf = REQ_OP_READ; > @@ -151,6 +151,26 @@ void bch_data_verify(struct cached_dev *dc, struct bio *bio) > bio_put(check); > } > > +void bch_data_verify(struct cached_dev *dc, struct bio *bio) > +{ > + struct request_queue *q = bdev_get_queue(bio->bi_bdev); > + struct bio *clone = bio_clone_fast(bio, GFP_NOIO, q->bio_split); > + unsigned sectors; > + > + while (!bio_can_convert_to_sp(clone, §ors)) { > + struct bio *split = bio_split(clone, sectors, > + GFP_NOIO, q->bio_split); > + > + __bch_data_verify(dc, split); > + bio_put(split); > + } > + > + if (bio_sectors(clone)) > + __bch_data_verify(dc, clone); > + > + bio_put(clone); > +} > + Hi Lei, The above patch is good IMHO. Just wondering why not use the classical style ? something like, do { if (!bio_can_convert_to_sp(clone, §ors)) split = bio_split(clone, sectors, GFP_NOIO, q->bio_split); else split = clone; __bch_data_verity(gc, split); bio_put(split); } while (split != clone); I guess maybe the above style generates less binary code. -- Coly Li -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html