block: split struct bio_integrity_payload

Many of the fields in struct bio_integrity_payload are only needed for
the default integrity buffer in the block layer, and the variable
sized array at the end of the structure makes it very hard to embed
into caller allocated structures.

Reduce struct bio_integrity_payload to the minimal structure needed in
common code and create two separate containing structures for the
automatically generated payload and the caller allocated payload.
The latter is a simple wrapper for struct bio_integrity_payload and
the bvecs, while the former contains the additional fields moved out
of struct bio_integrity_payload.

Always use a dedicated mempool for automatic integrity metadata
instead of depending on bio_set that is submitter controlled and thus
often doesn't have the mempool initialized and stop using mempools for
the submitter buffers as they aren't in the NOIO I/O submission path
where we need to guarantee forward progress.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250225154449.422989-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 22 insertions, 85 deletions

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index aa9f96612319..608594a154a5 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -7,13 +7,12 @@
  */
 
 #include <linux/blk-integrity.h>
-#include <linux/mempool.h>
-#include <linux/export.h>
-#include <linux/bio.h>
-#include <linux/slab.h>
 #include "blk.h"
 
-static struct kmem_cache *bip_slab;
+struct bio_integrity_alloc {
+	struct bio_integrity_payload	bip;
+	struct bio_vec			bvecs[];
+};
 
 /**
  * bio_integrity_free - Free bio integrity payload
@@ -23,21 +22,23 @@ static struct kmem_cache *bip_slab;
  */
 void bio_integrity_free(struct bio *bio)
 {
-	struct bio_integrity_payload *bip = bio_integrity(bio);
-	struct bio_set *bs = bio->bi_pool;
-
-	if (bs && mempool_initialized(&bs->bio_integrity_pool)) {
-		if (bip->bip_vec)
-			bvec_free(&bs->bvec_integrity_pool, bip->bip_vec,
-				  bip->bip_max_vcnt);
-		mempool_free(bip, &bs->bio_integrity_pool);
-	} else {
-		kfree(bip);
-	}
+	kfree(bio_integrity(bio));
 	bio->bi_integrity = NULL;
 	bio->bi_opf &= ~REQ_INTEGRITY;
 }
 
+void bio_integrity_init(struct bio *bio, struct bio_integrity_payload *bip,
+		struct bio_vec *bvecs, unsigned int nr_vecs)
+{
+	memset(bip, 0, sizeof(*bip));
+	bip->bip_max_vcnt = nr_vecs;
+	if (nr_vecs)
+		bip->bip_vec = bvecs;
+
+	bio->bi_integrity = bip;
+	bio->bi_opf |= REQ_INTEGRITY;
+}
+
 /**
  * bio_integrity_alloc - Allocate integrity payload and attach it to bio
  * @bio:	bio to attach integrity metadata to
@@ -52,48 +53,16 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
 						  gfp_t gfp_mask,
 						  unsigned int nr_vecs)
 {
-	struct bio_integrity_payload *bip;
-	struct bio_set *bs = bio->bi_pool;
-	unsigned inline_vecs;
+	struct bio_integrity_alloc *bia;
 
 	if (WARN_ON_ONCE(bio_has_crypt_ctx(bio)))
 		return ERR_PTR(-EOPNOTSUPP);
 
-	if (!bs || !mempool_initialized(&bs->bio_integrity_pool)) {
-		bip = kmalloc(struct_size(bip, bip_inline_vecs, nr_vecs), gfp_mask);
-		inline_vecs = nr_vecs;
-	} else {
-		bip = mempool_alloc(&bs->bio_integrity_pool, gfp_mask);
-		inline_vecs = BIO_INLINE_VECS;
-	}
-
-	if (unlikely(!bip))
+	bia = kmalloc(struct_size(bia, bvecs, nr_vecs), gfp_mask);
+	if (unlikely(!bia))
 		return ERR_PTR(-ENOMEM);
-
-	memset(bip, 0, sizeof(*bip));
-
-	/* always report as many vecs as asked explicitly, not inline vecs */
-	bip->bip_max_vcnt = nr_vecs;
-	if (nr_vecs > inline_vecs) {
-		bip->bip_vec = bvec_alloc(&bs->bvec_integrity_pool,
-					  &bip->bip_max_vcnt, gfp_mask);
-		if (!bip->bip_vec)
-			goto err;
-	} else if (nr_vecs) {
-		bip->bip_vec = bip->bip_inline_vecs;
-	}
-
-	bip->bip_bio = bio;
-	bio->bi_integrity = bip;
-	bio->bi_opf |= REQ_INTEGRITY;
-
-	return bip;
-err:
-	if (bs && mempool_initialized(&bs->bio_integrity_pool))
-		mempool_free(bip, &bs->bio_integrity_pool);
-	else
-		kfree(bip);
-	return ERR_PTR(-ENOMEM);
+	bio_integrity_init(bio, &bia->bip, bia->bvecs, nr_vecs);
+	return &bia->bip;
 }
 EXPORT_SYMBOL(bio_integrity_alloc);
 
@@ -467,35 +436,3 @@ int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
 
 	return 0;
 }
-
-int bioset_integrity_create(struct bio_set *bs, int pool_size)
-{
-	if (mempool_initialized(&bs->bio_integrity_pool))
-		return 0;
-
-	if (mempool_init_slab_pool(&bs->bio_integrity_pool,
-				   pool_size, bip_slab))
-		return -1;
-
-	if (biovec_init_pool(&bs->bvec_integrity_pool, pool_size)) {
-		mempool_exit(&bs->bio_integrity_pool);
-		return -1;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(bioset_integrity_create);
-
-void bioset_integrity_free(struct bio_set *bs)
-{
-	mempool_exit(&bs->bio_integrity_pool);
-	mempool_exit(&bs->bvec_integrity_pool);
-}
-
-void __init bio_integrity_init(void)
-{
-	bip_slab = kmem_cache_create("bio_integrity_payload",
-				     sizeof(struct bio_integrity_payload) +
-				     sizeof(struct bio_vec) * BIO_INLINE_VECS,
-				     0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
-}