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| author | Eric Biggers <ebiggers@google.com> | 2019-04-15 02:37:09 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2019-04-25 09:38:12 +0200 |
| commit | 877b5691f27a1aec0d9b53095a323e45c30069e2 (patch) | |
| tree | 59eba93e8d253fb0e12a0a2040de99e96e873933 /fs/ubifs/auth.c | |
| parent | crypto: nx - don't abuse shash MAY_SLEEP flag (diff) | |
| download | linux-877b5691f27a1aec0d9b53095a323e45c30069e2.tar.xz linux-877b5691f27a1aec0d9b53095a323e45c30069e2.zip | |
crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'fs/ubifs/auth.c')
| -rw-r--r-- | fs/ubifs/auth.c | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/fs/ubifs/auth.c b/fs/ubifs/auth.c index 5bf5fd08879e..b758004085c4 100644 --- a/fs/ubifs/auth.c +++ b/fs/ubifs/auth.c @@ -33,7 +33,6 @@ int __ubifs_node_calc_hash(const struct ubifs_info *c, const void *node, int err; shash->tfm = c->hash_tfm; - shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP; err = crypto_shash_digest(shash, node, le32_to_cpu(ch->len), hash); if (err < 0) @@ -56,7 +55,6 @@ static int ubifs_hash_calc_hmac(const struct ubifs_info *c, const u8 *hash, int err; shash->tfm = c->hmac_tfm; - shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP; err = crypto_shash_digest(shash, hash, c->hash_len, hmac); if (err < 0) @@ -88,7 +86,6 @@ int ubifs_prepare_auth_node(struct ubifs_info *c, void *node, return -ENOMEM; hash_desc->tfm = c->hash_tfm; - hash_desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; ubifs_shash_copy_state(c, inhash, hash_desc); err = crypto_shash_final(hash_desc, hash); @@ -123,7 +120,6 @@ static struct shash_desc *ubifs_get_desc(const struct ubifs_info *c, return ERR_PTR(-ENOMEM); desc->tfm = tfm; - desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; err = crypto_shash_init(desc); if (err) { @@ -364,7 +360,6 @@ static int ubifs_node_calc_hmac(const struct ubifs_info *c, const void *node, ubifs_assert(c, ofs_hmac + hmac_len < len); shash->tfm = c->hmac_tfm; - shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP; err = crypto_shash_init(shash); if (err) @@ -483,7 +478,6 @@ int ubifs_hmac_wkm(struct ubifs_info *c, u8 *hmac) return 0; shash->tfm = c->hmac_tfm; - shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP; err = crypto_shash_init(shash); if (err) |