From 93f221ae08381e994ac9f9ff6aa743e612e49718 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 15 Sep 2020 20:53:14 -0700 Subject: block: make blk_crypto_rq_bio_prep() able to fail blk_crypto_rq_bio_prep() assumes its gfp_mask argument always includes __GFP_DIRECT_RECLAIM, so that the mempool_alloc() will always succeed. However, blk_crypto_rq_bio_prep() might be called with GFP_ATOMIC via setup_clone() in drivers/md/dm-rq.c. This case isn't currently reachable with a bio that actually has an encryption context. However, it's fragile to rely on this. Just make blk_crypto_rq_bio_prep() able to fail. Suggested-by: Satya Tangirala Signed-off-by: Eric Biggers Reviewed-by: Mike Snitzer Reviewed-by: Satya Tangirala Cc: Miaohe Lin Signed-off-by: Jens Axboe --- block/blk-crypto-internal.h | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'block/blk-crypto-internal.h') diff --git a/block/blk-crypto-internal.h b/block/blk-crypto-internal.h index d2b0f565d83c..0d36aae538d7 100644 --- a/block/blk-crypto-internal.h +++ b/block/blk-crypto-internal.h @@ -142,13 +142,24 @@ static inline void blk_crypto_free_request(struct request *rq) __blk_crypto_free_request(rq); } -void __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, - gfp_t gfp_mask); -static inline void blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, - gfp_t gfp_mask) +int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, + gfp_t gfp_mask); +/** + * blk_crypto_rq_bio_prep - Prepare a request's crypt_ctx when its first bio + * is inserted + * @rq: The request to prepare + * @bio: The first bio being inserted into the request + * @gfp_mask: Memory allocation flags + * + * Return: 0 on success, -ENOMEM if out of memory. -ENOMEM is only possible if + * @gfp_mask doesn't include %__GFP_DIRECT_RECLAIM. + */ +static inline int blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, + gfp_t gfp_mask) { if (bio_has_crypt_ctx(bio)) - __blk_crypto_rq_bio_prep(rq, bio, gfp_mask); + return __blk_crypto_rq_bio_prep(rq, bio, gfp_mask); + return 0; } /** -- cgit v1.2.3