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 <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/fs/bio.c b/fs/bio.c
index 73b5447..40aa96e 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -160,12 +160,12 @@
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 @@
}
}
-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 @@
*/
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 @@
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 @@
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 @@
* 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 @@
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 @@
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);