Hi Martin, What do you think about adding gfp_mask parameter to bio_integrity_clone() like the attached patch? Kiyoshi Ueda and I are working on request-based device-mapper (*1) and it clones bios like the existing bio-based dm. However, since the request cloning may happen in interrupt context, GFP_ATOMIC is used in our case (*2). (*1) http://lkml.org/lkml/2008/10/3/177 (*2) http://lkml.org/lkml/2008/10/3/188 To cope with cloning the integrity payload, we want to pass gfp_mask to bio_integrity_clone(). It also seems natural to inherit gfp_mask from bio_clone when bio_integrity_clone is called from it. Since bio_clone() is the only caller of bio_integrity_clone() in 2.6.28-rc2 and all in-tree callers of bio_clone() are using GFP_NOIO, the patch does nothing other than changing the interface. Add gfp_mask parameter to bio_integrity_clone(). Stricter gfp_mask might be required for clone allocation. For example, request-based dm may clone bio in interrupt context so it has to use GFP_ATOMIC. Signed-off-by: Kiyoshi Ueda <k-ueda@xxxxxxxxxxxxx> Signed-off-by: Jun'ichi Nomura <j-nomura@xxxxxxxxxxxxx> Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Cc: Jens Axboe <jens.axboe@xxxxxxxxxx> Cc: Alasdair G Kergon <agk@xxxxxxxxxx> --- fs/bio-integrity.c | 5 +++-- fs/bio.c | 2 +- include/linux/bio.h | 4 ++-- 3 files changed, 6 insertions(+), 5 deletions(-) Index: linux-2.6.28-rc2/fs/bio-integrity.c =================================================================== --- linux-2.6.28-rc2.orig/fs/bio-integrity.c +++ linux-2.6.28-rc2/fs/bio-integrity.c @@ -681,19 +681,20 @@ EXPORT_SYMBOL(bio_integrity_split); * bio_integrity_clone - Callback for cloning bios with integrity metadata * @bio: New bio * @bio_src: Original bio + * @gfp_mask: Memory allocation mask * @bs: bio_set to allocate bip from * * Description: Called to allocate a bip when cloning a bio */ int bio_integrity_clone(struct bio *bio, struct bio *bio_src, - struct bio_set *bs) + gfp_t gfp_mask, struct bio_set *bs) { struct bio_integrity_payload *bip_src = bio_src->bi_integrity; struct bio_integrity_payload *bip; BUG_ON(bip_src == NULL); - bip = bio_integrity_alloc_bioset(bio, GFP_NOIO, bip_src->bip_vcnt, bs); + bip = bio_integrity_alloc_bioset(bio, gfp_mask, bip_src->bip_vcnt, bs); if (bip == NULL) return -EIO; Index: linux-2.6.28-rc2/include/linux/bio.h =================================================================== --- linux-2.6.28-rc2.orig/include/linux/bio.h +++ linux-2.6.28-rc2/include/linux/bio.h @@ -496,7 +496,7 @@ extern void bio_integrity_endio(struct b extern void bio_integrity_advance(struct bio *, unsigned int); extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); extern void bio_integrity_split(struct bio *, struct bio_pair *, int); -extern int bio_integrity_clone(struct bio *, struct bio *, struct bio_set *); +extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *); extern int bioset_integrity_create(struct bio_set *, int); extern void bioset_integrity_free(struct bio_set *); extern void bio_integrity_init_slab(void); @@ -507,7 +507,7 @@ extern void bio_integrity_init_slab(void #define bioset_integrity_create(a, b) (0) #define bio_integrity_prep(a) (0) #define bio_integrity_enabled(a) (0) -#define bio_integrity_clone(a, b, c) (0) +#define bio_integrity_clone(a, b, c, d) (0) #define bioset_integrity_free(a) do { } while (0) #define bio_integrity_free(a, b) do { } while (0) #define bio_integrity_endio(a, b) do { } while (0) Index: linux-2.6.28-rc2/fs/bio.c =================================================================== --- linux-2.6.28-rc2.orig/fs/bio.c +++ linux-2.6.28-rc2/fs/bio.c @@ -309,7 +309,7 @@ struct bio *bio_clone(struct bio *bio, g if (bio_integrity(bio)) { int ret; - ret = bio_integrity_clone(b, bio, fs_bio_set); + ret = bio_integrity_clone(b, bio, gfp_mask, fs_bio_set); if (ret < 0) return NULL; -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
