diff options
| author | Eric Biggers <ebiggers@google.com> | 2020-09-15 20:53:15 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-10-05 10:47:43 -0600 |
| commit | cf785af19319f9fc0fc0c0604d259f1ef31b502f (patch) | |
| tree | b047fc45f79597a6943d9408e66a376483c4b5c3 /block | |
| parent | 93f221ae08381e994ac9f9ff6aa743e612e49718 (diff) | |
block: warn if !__GFP_DIRECT_RECLAIM in bio_crypt_set_ctx()
bio_crypt_set_ctx() assumes its gfp_mask argument always includes
__GFP_DIRECT_RECLAIM, so that the mempool_alloc() will always succeed.
For now this assumption is still fine, since no callers violate it.
Making bio_crypt_set_ctx() able to fail would add unneeded complexity.
However, if a caller didn't use __GFP_DIRECT_RECLAIM, it would be very
hard to notice the bug. Make it easier by adding a WARN_ON_ONCE().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Satya Tangirala <satyat@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Satya Tangirala <satyat@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-crypto.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/block/blk-crypto.c b/block/blk-crypto.c index bbe7974fd74f..5da43f0973b4 100644 --- a/block/blk-crypto.c +++ b/block/blk-crypto.c @@ -81,7 +81,15 @@ subsys_initcall(bio_crypt_ctx_init); void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key, const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], gfp_t gfp_mask) { - struct bio_crypt_ctx *bc = mempool_alloc(bio_crypt_ctx_pool, gfp_mask); + struct bio_crypt_ctx *bc; + + /* + * The caller must use a gfp_mask that contains __GFP_DIRECT_RECLAIM so + * that the mempool_alloc() can't fail. + */ + WARN_ON_ONCE(!(gfp_mask & __GFP_DIRECT_RECLAIM)); + + bc = mempool_alloc(bio_crypt_ctx_pool, gfp_mask); bc->bc_key = key; memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun)); |