[PATCH 11/14] block: clone crypto and integrity data in __bio_clone_fast

[Christoph Hellwig <hch@lst.de>]

__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 the other callers also don't need to handle failure, as 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>
---
 block/bio-integrity.c       |  1 -
 block/bio.c                 | 26 +++++++++++++-------------
 block/blk-crypto.c          |  1 -
 drivers/md/bcache/request.c |  2 +-
 drivers/md/dm.c             | 35 ++++++++---------------------------
 drivers/md/md-multipath.c   |  2 +-
 include/linux/bio.h         |  2 +-
 7 files changed, 24 insertions(+), 45 deletions(-)

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index d251147154592..bd54532200650 100644
--- a/block/bio-integrity.c
+++ b/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)
 {
diff --git a/block/bio.c b/block/bio.c
index 03cefe81950f2..60f79b33a49af 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -730,6 +730,7 @@ 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
@@ -737,7 +738,7 @@ EXPORT_SYMBOL(bio_put);
  *
  * 	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);
 
@@ -759,6 +760,13 @@ 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);
 
@@ -778,20 +786,12 @@ 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);
 
diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index ec9efeeeca918..773dae4c329ba 100644
--- a/block/blk-crypto.c
+++ b/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],
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 7ba59d08ed870..574b02b94f1a4 100644
--- a/drivers/md/bcache/request.c
+++ b/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,
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 57f44d3a4d747..5978cb87e9372 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -553,6 +553,10 @@ static struct bio *alloc_tio(struct clone_info *ci, struct dm_target *ti,
 		/* the dm_target_io embedded in ci->io is available */
 		tio = &ci->io->tio;
 		bio_init(&tio->clone, NULL, NULL, 0, 0);
+		if (__bio_clone_fast(&tio->clone, ci->bio, gfp_mask) < 0) {
+			bio_uninit(&tio->clone);
+			return NULL;
+		}
 	} else {
 		struct bio *clone = bio_alloc_bioset(NULL, 0, 0, gfp_mask,
 						     &ci->io->md->bs);
@@ -561,8 +565,11 @@ static struct bio *alloc_tio(struct clone_info *ci, struct dm_target *ti,
 
 		tio = clone_to_tio(clone);
 		tio->inside_dm_io = false;
+		if (__bio_clone_fast(&tio->clone, ci->bio, gfp_mask) < 0) {
+			bio_put(clone);
+			return NULL;
+		}
 	}
-	__bio_clone_fast(&tio->clone, ci->bio);
 
 	tio->magic = DM_TIO_MAGIC;
 	tio->io = ci->io;
@@ -1197,31 +1204,8 @@ 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);
 
@@ -1230,9 +1214,6 @@ 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,
diff --git a/drivers/md/md-multipath.c b/drivers/md/md-multipath.c
index 5e15940634d85..010c759c741ad 100644
--- a/drivers/md/md-multipath.c
+++ b/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);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 18cfe5bb41ea8..b814361c957b0 100644
--- a/include/linux/bio.h
+++ b/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;
-- 
2.30.2