From 9f060e2231ca96ca94f2ffcff730acd72606b280 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Fri, 12 Oct 2012 15:29:33 -0700 Subject: block: Convert integrity to bvec_alloc_bs() This adds a pointer to the bvec array to struct bio_integrity_payload, instead of the bvecs always being inline; then the bvecs are allocated with bvec_alloc_bs(). Changed bvec_alloc_bs() and bvec_free_bs() to take a pointer to a mempool instead of the bioset, so that bio integrity can use a different mempool for its bvecs, and thus avoid a potential deadlock. This is eventually for immutable bio vecs - immutable bvecs aren't useful if we still have to copy them, hence the need for the pointer. Less code is always nice too, though. Also, bio_integrity_alloc() was using fs_bio_set if no bio_set was specified. This was wrong - using the bio_set doesn't protect us from memory allocation failures, because we just used kmalloc for the bio_integrity_payload. But it does introduce the possibility of deadlock, if for some reason we weren't supposed to be using fs_bio_set. Signed-off-by: Kent Overstreet CC: Jens Axboe CC: Martin K. Petersen --- fs/bio.c | 36 +++++++++++++++--------------------- 1 file changed, 15 insertions(+), 21 deletions(-) (limited to 'fs/bio.c') diff --git a/fs/bio.c b/fs/bio.c index 73b54470994..40aa96eae99 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -160,12 +160,12 @@ unsigned int bvec_nr_vecs(unsigned short idx) return bvec_slabs[idx].nr_vecs; } -void bvec_free_bs(struct bio_set *bs, struct bio_vec *bv, unsigned int idx) +void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned int idx) { BIO_BUG_ON(idx >= BIOVEC_NR_POOLS); if (idx == BIOVEC_MAX_IDX) - mempool_free(bv, bs->bvec_pool); + mempool_free(bv, pool); else { struct biovec_slab *bvs = bvec_slabs + idx; @@ -173,8 +173,8 @@ void bvec_free_bs(struct bio_set *bs, struct bio_vec *bv, unsigned int idx) } } -struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, - struct bio_set *bs) +struct bio_vec *bvec_alloc(gfp_t gfp_mask, int nr, unsigned long *idx, + mempool_t *pool) { struct bio_vec *bvl; @@ -210,7 +210,7 @@ struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, */ if (*idx == BIOVEC_MAX_IDX) { fallback: - bvl = mempool_alloc(bs->bvec_pool, gfp_mask); + bvl = mempool_alloc(pool, gfp_mask); } else { struct biovec_slab *bvs = bvec_slabs + *idx; gfp_t __gfp_mask = gfp_mask & ~(__GFP_WAIT | __GFP_IO); @@ -253,7 +253,7 @@ static void bio_free(struct bio *bio) if (bs) { if (bio_has_allocated_vec(bio)) - bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio)); + bvec_free(bs->bvec_pool, bio->bi_io_vec, BIO_POOL_IDX(bio)); /* * If we have front padding, adjust the bio pointer before freeing @@ -442,11 +442,11 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) bio_init(bio); if (nr_iovecs > inline_vecs) { - bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs); + bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, bs->bvec_pool); if (!bvl && gfp_mask != saved_gfp) { punt_bios_to_rescuer(bs); gfp_mask = saved_gfp; - bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs); + bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx, bs->bvec_pool); } if (unlikely(!bvl)) @@ -1661,20 +1661,11 @@ EXPORT_SYMBOL(bio_sector_offset); * create memory pools for biovec's in a bio_set. * use the global biovec slabs created for general use. */ -static int biovec_create_pools(struct bio_set *bs, int pool_entries) +mempool_t *biovec_create_pool(struct bio_set *bs, int pool_entries) { struct biovec_slab *bp = bvec_slabs + BIOVEC_MAX_IDX; - bs->bvec_pool = mempool_create_slab_pool(pool_entries, bp->slab); - if (!bs->bvec_pool) - return -ENOMEM; - - return 0; -} - -static void biovec_free_pools(struct bio_set *bs) -{ - mempool_destroy(bs->bvec_pool); + return mempool_create_slab_pool(pool_entries, bp->slab); } void bioset_free(struct bio_set *bs) @@ -1685,8 +1676,10 @@ void bioset_free(struct bio_set *bs) if (bs->bio_pool) mempool_destroy(bs->bio_pool); + if (bs->bvec_pool) + mempool_destroy(bs->bvec_pool); + bioset_integrity_free(bs); - biovec_free_pools(bs); bio_put_slab(bs); kfree(bs); @@ -1731,7 +1724,8 @@ struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad) if (!bs->bio_pool) goto bad; - if (biovec_create_pools(bs, pool_size)) + bs->bvec_pool = biovec_create_pool(bs, pool_size); + if (!bs->bvec_pool) goto bad; bs->rescue_workqueue = alloc_workqueue("bioset", WQ_MEM_RECLAIM, 0); -- cgit v1.2.3