From e546fe1da9bd47a6fddce6b37c17b1aa1811f7d3 Mon Sep 17 00:00:00 2001 From: John Garry Date: Mon, 11 Nov 2024 11:21:45 +0000 Subject: [PATCH] block: Rework bio_split() return value Instead of returning an inconclusive value of NULL for an error in calling bio_split(), return a ERR_PTR() always. Also remove the BUG_ON() calls, and WARN_ON_ONCE() instead. Indeed, since almost all callers don't check the return code from bio_split(), we'll crash anyway (for those failures). Fix up the only user which checks bio_split() return code today (directly or indirectly), blk_crypto_fallback_split_bio_if_needed(). The md/bcache code does check the return code in cached_dev_cache_miss() -> bio_next_split() -> bio_split(), but only to see if there was a split, so there would be no change in behaviour here (when returning a ERR_PTR()). Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: John Garry Link: https://lore.kernel.org/r/20241111112150.3756529-2-john.g.garry@oracle.com Signed-off-by: Jens Axboe --- block/bio.c | 10 ++++++---- block/blk-crypto-fallback.c | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/block/bio.c b/block/bio.c index daceb0a5c1d7..948b22825510 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1665,16 +1665,18 @@ struct bio *bio_split(struct bio *bio, int sectors, { struct bio *split; - BUG_ON(sectors <= 0); - BUG_ON(sectors >= bio_sectors(bio)); + if (WARN_ON_ONCE(sectors <= 0)) + return ERR_PTR(-EINVAL); + if (WARN_ON_ONCE(sectors >= bio_sectors(bio))) + return ERR_PTR(-EINVAL); /* Zone append commands cannot be split */ if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND)) - return NULL; + return ERR_PTR(-EINVAL); split = bio_alloc_clone(bio->bi_bdev, bio, gfp, bs); if (!split) - return NULL; + return ERR_PTR(-ENOMEM); split->bi_iter.bi_size = sectors << 9; diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c index b1e7415f8439..29a205482617 100644 --- a/block/blk-crypto-fallback.c +++ b/block/blk-crypto-fallback.c @@ -226,7 +226,7 @@ static bool blk_crypto_fallback_split_bio_if_needed(struct bio **bio_ptr) split_bio = bio_split(bio, num_sectors, GFP_NOIO, &crypto_bio_split); - if (!split_bio) { + if (IS_ERR(split_bio)) { bio->bi_status = BLK_STS_RESOURCE; return false; }