Commit cf785af1 authored by Eric Biggers's avatar Eric Biggers Committed by Jens Axboe

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: default avatarEric Biggers <ebiggers@google.com>
Reviewed-by: default avatarSatya Tangirala <satyat@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Satya Tangirala <satyat@google.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 93f221ae
...@@ -81,7 +81,15 @@ subsys_initcall(bio_crypt_ctx_init); ...@@ -81,7 +81,15 @@ subsys_initcall(bio_crypt_ctx_init);
void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key, 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) 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; bc->bc_key = key;
memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun)); memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun));
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment