block: clone crypto and integrity data in __bio_clone_fast

__bio_clone_fast should also clone integrity and crypto data, as a clone
without those is incomplete.  Right now the only caller that can actually
support crypto and integrity data (dm) does it manually for the one
callchain that supports these, but we better do it properly in the core.

Note that all callers except for the above mentioned one also don't need
to handle failure at all, given that the integrity and crypto clones are
based on mempool allocations that won't fail for sleeping allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20220202160109.108149-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/bio-integrity.c

@@ -420,7 +420,6 @@ int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
 
 	return 0;
 }
-EXPORT_SYMBOL(bio_integrity_clone);
 
 int bioset_integrity_create(struct bio_set *bs, int pool_size)
 {

block/bio.c

@@ -732,14 +732,15 @@ EXPORT_SYMBOL(bio_put);
  * 	__bio_clone_fast - clone a bio that shares the original bio's biovec
  * 	@bio: destination bio
  * 	@bio_src: bio to clone
+ *	@gfp: allocation flags
  *
  *	Clone a &bio. Caller will own the returned bio, but not
  *	the actual data it points to. Reference count of returned
  * 	bio will be one.
  *
  * 	Caller must ensure that @bio_src is not freed before @bio.
  */
-void __bio_clone_fast(struct bio *bio, struct bio *bio_src)
+int __bio_clone_fast(struct bio *bio, struct bio *bio_src, gfp_t gfp)
 {
 	WARN_ON_ONCE(bio->bi_pool && bio->bi_max_vecs);
 
@@ -761,6 +762,13 @@ void __bio_clone_fast(struct bio *bio, struct bio *bio_src)
 
 	bio_clone_blkg_association(bio, bio_src);
 	blkcg_bio_issue_init(bio);
+
+	if (bio_crypt_clone(bio, bio_src, gfp) < 0)
+		return -ENOMEM;
+	if (bio_integrity(bio_src) &&
+	    bio_integrity_clone(bio, bio_src, gfp) < 0)
+		return -ENOMEM;
+	return 0;
 }
 EXPORT_SYMBOL(__bio_clone_fast);
 
@@ -780,20 +788,12 @@ struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs)
 	if (!b)
 		return NULL;
 
-	__bio_clone_fast(b, bio);
-
-	if (bio_crypt_clone(b, bio, gfp_mask) < 0)
-		goto err_put;
-
-	if (bio_integrity(bio) &&
-	    bio_integrity_clone(b, bio, gfp_mask) < 0)
-		goto err_put;
+	if (__bio_clone_fast(b, bio, gfp_mask < 0)) {
+		bio_put(b);
+		return NULL;
+	}
 
 	return b;
-
-err_put:
-	bio_put(b);
-	return NULL;
 }
 EXPORT_SYMBOL(bio_clone_fast);
 

block/blk-crypto.c

@@ -111,7 +111,6 @@ int __bio_crypt_clone(struct bio *dst, struct bio *src, gfp_t gfp_mask)
 	*dst->bi_crypt_context = *src->bi_crypt_context;
 	return 0;
 }
-EXPORT_SYMBOL_GPL(__bio_crypt_clone);
 
 /* Increments @dun by @inc, treating @dun as a multi-limb integer. */
 void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],

drivers/md/bcache/request.c

@@ -686,7 +686,7 @@ static void do_bio_hook(struct search *s,
 	struct bio *bio = &s->bio.bio;
 
 	bio_init(bio, NULL, NULL, 0, 0);
-	__bio_clone_fast(bio, orig_bio);
+	__bio_clone_fast(bio, orig_bio, GFP_NOIO);
 	/*
 	 * bi_end_io can be set separately somewhere else, e.g. the
 	 * variants in,

drivers/md/dm.c

@@ -561,7 +561,12 @@ static struct bio *alloc_tio(struct clone_info *ci, struct dm_target *ti,
 		tio = clone_to_tio(clone);
 		tio->inside_dm_io = false;
 	}
-	__bio_clone_fast(&tio->clone, ci->bio);
+
+	if (__bio_clone_fast(&tio->clone, ci->bio, gfp_mask) < 0) {
+		if (ci->io->tio.io)
+			bio_put(&tio->clone);
+		return NULL;
+	}
 
 	tio->magic = DM_TIO_MAGIC;
 	tio->io = ci->io;
@@ -1196,31 +1201,8 @@ static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti,
 				    sector_t sector, unsigned *len)
 {
 	struct bio *bio = ci->bio, *clone;
-	int r;
 
 	clone = alloc_tio(ci, ti, 0, len, GFP_NOIO);
-
-	r = bio_crypt_clone(clone, bio, GFP_NOIO);
-	if (r < 0)
-		goto free_tio;
-
-	if (bio_integrity(bio)) {
-		struct dm_target_io *tio = clone_to_tio(clone);
-
-		if (unlikely(!dm_target_has_integrity(tio->ti->type) &&
-			     !dm_target_passes_integrity(tio->ti->type))) {
-			DMWARN("%s: the target %s doesn't support integrity data.",
-				dm_device_name(tio->io->md),
-				tio->ti->type->name);
-			r = -EIO;
-			goto free_tio;
-		}
-
-		r = bio_integrity_clone(clone, bio, GFP_NOIO);
-		if (r < 0)
-			goto free_tio;
-	}
-
 	bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector));
 	clone->bi_iter.bi_size = to_bytes(*len);
 
@@ -1229,9 +1211,6 @@ static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti,
 
 	__map_bio(clone);
 	return 0;
-free_tio:
-	free_tio(clone);
-	return r;
 }
 
 static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci,

drivers/md/md-multipath.c

@@ -122,7 +122,7 @@ static bool multipath_make_request(struct mddev *mddev, struct bio * bio)
 	multipath = conf->multipaths + mp_bh->path;
 
 	bio_init(&mp_bh->bio, NULL, NULL, 0, 0);
-	__bio_clone_fast(&mp_bh->bio, bio);
+	__bio_clone_fast(&mp_bh->bio, bio, GFP_NOIO);
 
 	mp_bh->bio.bi_iter.bi_sector += multipath->rdev->data_offset;
 	bio_set_dev(&mp_bh->bio, multipath->rdev->bdev);

include/linux/bio.h

@@ -413,7 +413,7 @@ struct bio *bio_alloc_kiocb(struct kiocb *kiocb, struct block_device *bdev,
 struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs);
 extern void bio_put(struct bio *);
 
-extern void __bio_clone_fast(struct bio *, struct bio *);
+int __bio_clone_fast(struct bio *bio, struct bio *bio_src, gfp_t gfp);
 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
 
 extern struct bio_set fs_bio_set;