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>

25 files changed, 0 insertions, 40 deletions

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index c7ad88d91a09..843a9b9b3d74 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -5443,7 +5443,6 @@ static int drbd_do_auth(struct drbd_connection *connection)
 	rcu_read_unlock();
 
 	desc->tfm = connection->cram_hmac_tfm;
-	desc->flags = 0;
 
 	rv = crypto_shash_setkey(connection->cram_hmac_tfm, (u8 *)secret, key_len);
 	if (rv) {
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 268ef0c5d4ab..6781bcf3ec26 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -304,7 +304,6 @@ void drbd_csum_ee(struct crypto_shash *tfm, struct drbd_peer_request *peer_req,
 	void *src;
 
 	desc->tfm = tfm;
-	desc->flags = 0;
 
 	crypto_shash_init(desc);
 
@@ -332,7 +331,6 @@ void drbd_csum_bio(struct crypto_shash *tfm, struct bio *bio, void *digest)
 	struct bvec_iter iter;
 
 	desc->tfm = tfm;
-	desc->flags = 0;
 
 	crypto_shash_init(desc);
 
diff --git a/drivers/crypto/axis/artpec6_crypto.c b/drivers/crypto/axis/artpec6_crypto.c
index 57e5dca3253f..d2fb72811442 100644
--- a/drivers/crypto/axis/artpec6_crypto.c
+++ b/drivers/crypto/axis/artpec6_crypto.c
@@ -2247,8 +2247,6 @@ artpec6_crypto_hash_set_key(struct crypto_ahash *tfm,
 		SHASH_DESC_ON_STACK(hdesc, tfm_ctx->child_hash);
 
 		hdesc->tfm = tfm_ctx->child_hash;
-		hdesc->flags = crypto_ahash_get_flags(tfm) &
-			       CRYPTO_TFM_REQ_MAY_SLEEP;
 
 		tfm_ctx->hmac_key_length = blocksize;
 		ret = crypto_shash_digest(hdesc, key, keylen,
diff --git a/drivers/crypto/bcm/cipher.c b/drivers/crypto/bcm/cipher.c
index 8862200d4a0b..25f8d3913ceb 100644
--- a/drivers/crypto/bcm/cipher.c
+++ b/drivers/crypto/bcm/cipher.c
@@ -2140,7 +2140,6 @@ static int ahash_init(struct ahash_request *req)
 			goto err_hash;
 		}
 		ctx->shash->tfm = hash;
-		ctx->shash->flags = 0;
 
 		/* Set the key using data we already have from setkey */
 		if (ctx->authkeylen > 0) {
diff --git a/drivers/crypto/bcm/util.c b/drivers/crypto/bcm/util.c
index d8cda5fb75ad..91ec56399d84 100644
--- a/drivers/crypto/bcm/util.c
+++ b/drivers/crypto/bcm/util.c
@@ -242,7 +242,6 @@ int do_shash(unsigned char *name, unsigned char *result,
 		goto do_shash_err;
 	}
 	sdesc->shash.tfm = hash;
-	sdesc->shash.flags = 0x0;
 
 	if (key_len > 0) {
 		rc = crypto_shash_setkey(hash, key, key_len);
diff --git a/drivers/crypto/ccp/ccp-crypto-sha.c b/drivers/crypto/ccp/ccp-crypto-sha.c
index 10a61cd54fce..3e10573f589e 100644
--- a/drivers/crypto/ccp/ccp-crypto-sha.c
+++ b/drivers/crypto/ccp/ccp-crypto-sha.c
@@ -293,8 +293,6 @@ static int ccp_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
 	if (key_len > block_size) {
 		/* Must hash the input key */
 		sdesc->tfm = shash;
-		sdesc->flags = crypto_ahash_get_flags(tfm) &
-			CRYPTO_TFM_REQ_MAY_SLEEP;
 
 		ret = crypto_shash_digest(sdesc, key, key_len,
 					  ctx->u.sha.key);
diff --git a/drivers/crypto/chelsio/chcr_algo.c b/drivers/crypto/chelsio/chcr_algo.c
index 8d8cf80b9294..8a76fce22943 100644
--- a/drivers/crypto/chelsio/chcr_algo.c
+++ b/drivers/crypto/chelsio/chcr_algo.c
@@ -2130,7 +2130,6 @@ static int chcr_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 	 * ipad in hmacctx->ipad and opad in hmacctx->opad location
 	 */
 	shash->tfm = hmacctx->base_hash;
-	shash->flags = crypto_shash_get_flags(hmacctx->base_hash);
 	if (keylen > bs) {
 		err = crypto_shash_digest(shash, key, keylen,
 					  hmacctx->ipad);
@@ -3517,7 +3516,6 @@ static int chcr_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
 		SHASH_DESC_ON_STACK(shash, base_hash);
 
 		shash->tfm = base_hash;
-		shash->flags = crypto_shash_get_flags(base_hash);
 		bs = crypto_shash_blocksize(base_hash);
 		align = KEYCTX_ALIGN_PAD(max_authsize);
 		o_ptr =  actx->h_iopad + param.result_size + align;
diff --git a/drivers/crypto/mediatek/mtk-sha.c b/drivers/crypto/mediatek/mtk-sha.c
index 5f4f845adbb8..a0806ba40c68 100644
--- a/drivers/crypto/mediatek/mtk-sha.c
+++ b/drivers/crypto/mediatek/mtk-sha.c
@@ -365,7 +365,6 @@ static int mtk_sha_finish_hmac(struct ahash_request *req)
 	SHASH_DESC_ON_STACK(shash, bctx->shash);
 
 	shash->tfm = bctx->shash;
-	shash->flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */
 
 	return crypto_shash_init(shash) ?:
 	       crypto_shash_update(shash, bctx->opad, ctx->bs) ?:
@@ -810,8 +809,6 @@ static int mtk_sha_setkey(struct crypto_ahash *tfm, const u8 *key,
 	SHASH_DESC_ON_STACK(shash, bctx->shash);
 
 	shash->tfm = bctx->shash;
-	shash->flags = crypto_shash_get_flags(bctx->shash) &
-		       CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	if (keylen > bs) {
 		err = crypto_shash_digest(shash, key, keylen, bctx->ipad);
diff --git a/drivers/crypto/n2_core.c b/drivers/crypto/n2_core.c
index df675aea58f6..0d5d3d8eb680 100644
--- a/drivers/crypto/n2_core.c
+++ b/drivers/crypto/n2_core.c
@@ -469,8 +469,6 @@ static int n2_hmac_async_setkey(struct crypto_ahash *tfm, const u8 *key,
 		return err;
 
 	shash->tfm = child_shash;
-	shash->flags = crypto_ahash_get_flags(tfm) &
-		CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	bs = crypto_shash_blocksize(child_shash);
 	ds = crypto_shash_digestsize(child_shash);
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
index 0641185bd82f..51b20abac464 100644
--- a/drivers/crypto/omap-sham.c
+++ b/drivers/crypto/omap-sham.c
@@ -1055,7 +1055,6 @@ static int omap_sham_finish_hmac(struct ahash_request *req)
 	SHASH_DESC_ON_STACK(shash, bctx->shash);
 
 	shash->tfm = bctx->shash;
-	shash->flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */
 
 	return crypto_shash_init(shash) ?:
 	       crypto_shash_update(shash, bctx->opad, bs) ?:
@@ -1226,7 +1225,6 @@ static int omap_sham_shash_digest(struct crypto_shash *tfm, u32 flags,
 	SHASH_DESC_ON_STACK(shash, tfm);
 
 	shash->tfm = tfm;
-	shash->flags = flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	return crypto_shash_digest(shash, data, len, out);
 }
diff --git a/drivers/crypto/padlock-sha.c b/drivers/crypto/padlock-sha.c
index 21e5cae0a1e0..e641481a3cd9 100644
--- a/drivers/crypto/padlock-sha.c
+++ b/drivers/crypto/padlock-sha.c
@@ -39,7 +39,6 @@ static int padlock_sha_init(struct shash_desc *desc)
 	struct padlock_sha_ctx *ctx = crypto_shash_ctx(desc->tfm);
 
 	dctx->fallback.tfm = ctx->fallback;
-	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 	return crypto_shash_init(&dctx->fallback);
 }
 
@@ -48,7 +47,6 @@ static int padlock_sha_update(struct shash_desc *desc,
 {
 	struct padlock_sha_desc *dctx = shash_desc_ctx(desc);
 
-	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 	return crypto_shash_update(&dctx->fallback, data, length);
 }
 
@@ -65,7 +63,6 @@ static int padlock_sha_import(struct shash_desc *desc, const void *in)
 	struct padlock_sha_ctx *ctx = crypto_shash_ctx(desc->tfm);
 
 	dctx->fallback.tfm = ctx->fallback;
-	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 	return crypto_shash_import(&dctx->fallback, in);
 }
 
@@ -91,7 +88,6 @@ static int padlock_sha1_finup(struct shash_desc *desc, const u8 *in,
 	unsigned int leftover;
 	int err;
 
-	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 	err = crypto_shash_export(&dctx->fallback, &state);
 	if (err)
 		goto out;
@@ -153,7 +149,6 @@ static int padlock_sha256_finup(struct shash_desc *desc, const u8 *in,
 	unsigned int leftover;
 	int err;
 
-	dctx->fallback.flags = desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP;
 	err = crypto_shash_export(&dctx->fallback, &state);
 	if (err)
 		goto out;
diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c
index 975c75198f56..c8d401646902 100644
--- a/drivers/crypto/qat/qat_common/qat_algs.c
+++ b/drivers/crypto/qat/qat_common/qat_algs.c
@@ -164,7 +164,6 @@ static int qat_alg_do_precomputes(struct icp_qat_hw_auth_algo_blk *hash,
 	memset(ctx->ipad, 0, block_size);
 	memset(ctx->opad, 0, block_size);
 	shash->tfm = ctx->hash_tfm;
-	shash->flags = 0x0;
 
 	if (auth_keylen > block_size) {
 		int ret = crypto_shash_digest(shash, auth_key,
diff --git a/drivers/crypto/s5p-sss.c b/drivers/crypto/s5p-sss.c
index 1afdcb81d8ed..9ef25230c199 100644
--- a/drivers/crypto/s5p-sss.c
+++ b/drivers/crypto/s5p-sss.c
@@ -1534,7 +1534,6 @@ static int s5p_hash_shash_digest(struct crypto_shash *tfm, u32 flags,
 	SHASH_DESC_ON_STACK(shash, tfm);
 
 	shash->tfm = tfm;
-	shash->flags = flags & ~CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	return crypto_shash_digest(shash, data, len, out);
 }
diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c
index 611ff591410e..b5a6883bb09e 100644
--- a/drivers/crypto/vmx/ghash.c
+++ b/drivers/crypto/vmx/ghash.c
@@ -101,7 +101,6 @@ static int p8_ghash_init(struct shash_desc *desc)
 	dctx->bytes = 0;
 	memset(dctx->shash, 0, GHASH_DIGEST_SIZE);
 	dctx->fallback_desc.tfm = ctx->fallback;
-	dctx->fallback_desc.flags = desc->flags;
 	return crypto_shash_init(&dctx->fallback_desc);
 }
 
diff --git a/drivers/infiniband/sw/rxe/rxe.h b/drivers/infiniband/sw/rxe/rxe.h
index 2e2dff478833..ecf6e659c0da 100644
--- a/drivers/infiniband/sw/rxe/rxe.h
+++ b/drivers/infiniband/sw/rxe/rxe.h
@@ -80,7 +80,6 @@ static inline u32 rxe_crc32(struct rxe_dev *rxe,
 	SHASH_DESC_ON_STACK(shash, rxe->tfm);
 
 	shash->tfm = rxe->tfm;
-	shash->flags = 0;
 	*(u32 *)shash_desc_ctx(shash) = crc;
 	err = crypto_shash_update(shash, next, len);
 	if (unlikely(err)) {
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index dd6565798778..9faed1c92b52 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -332,7 +332,6 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
 	int err;
 
 	desc->tfm = essiv->hash_tfm;
-	desc->flags = 0;
 
 	err = crypto_shash_digest(desc, cc->key, cc->key_size, essiv->salt);
 	shash_desc_zero(desc);
@@ -606,7 +605,6 @@ static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
 	int i, r;
 
 	desc->tfm = lmk->hash_tfm;
-	desc->flags = 0;
 
 	r = crypto_shash_init(desc);
 	if (r)
@@ -768,7 +766,6 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
 
 	/* calculate crc32 for every 32bit part and xor it */
 	desc->tfm = tcw->crc32_tfm;
-	desc->flags = 0;
 	for (i = 0; i < 4; i++) {
 		r = crypto_shash_init(desc);
 		if (r)
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index d57d997a52c8..1366d886907c 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -532,7 +532,6 @@ static void section_mac(struct dm_integrity_c *ic, unsigned section, __u8 result
 	unsigned j, size;
 
 	desc->tfm = ic->journal_mac;
-	desc->flags = 0;
 
 	r = crypto_shash_init(desc);
 	if (unlikely(r)) {
@@ -1278,7 +1277,6 @@ static void integrity_sector_checksum(struct dm_integrity_c *ic, sector_t sector
 	unsigned digest_size;
 
 	req->tfm = ic->internal_hash;
-	req->flags = 0;
 
 	r = crypto_shash_init(req);
 	if (unlikely(r < 0)) {
diff --git a/drivers/net/ppp/ppp_mppe.c b/drivers/net/ppp/ppp_mppe.c
index 7ccdc62c6052..ff61dd8748de 100644
--- a/drivers/net/ppp/ppp_mppe.c
+++ b/drivers/net/ppp/ppp_mppe.c
@@ -222,7 +222,6 @@ static void *mppe_alloc(unsigned char *options, int optlen)
 		goto out_free;
 	}
 	state->sha1->tfm = shash;
-	state->sha1->flags = 0;
 
 	digestsize = crypto_shash_digestsize(shash);
 	if (digestsize < MPPE_MAX_KEY_LEN)
diff --git a/drivers/net/wireless/intersil/orinoco/mic.c b/drivers/net/wireless/intersil/orinoco/mic.c
index 67b0c05afbdb..a324bc4b7938 100644
--- a/drivers/net/wireless/intersil/orinoco/mic.c
+++ b/drivers/net/wireless/intersil/orinoco/mic.c
@@ -65,7 +65,6 @@ int orinoco_mic(struct crypto_shash *tfm_michael, u8 *key,
 	hdr[ETH_ALEN * 2 + 3] = 0;
 
 	desc->tfm = tfm_michael;
-	desc->flags = 0;
 
 	err = crypto_shash_setkey(tfm_michael, key, MIC_KEYLEN);
 	if (err)
diff --git a/drivers/nfc/s3fwrn5/firmware.c b/drivers/nfc/s3fwrn5/firmware.c
index b7828fb252f2..b681073ae8ba 100644
--- a/drivers/nfc/s3fwrn5/firmware.c
+++ b/drivers/nfc/s3fwrn5/firmware.c
@@ -449,7 +449,6 @@ int s3fwrn5_fw_download(struct s3fwrn5_fw_info *fw_info)
 		SHASH_DESC_ON_STACK(desc, tfm);
 
 		desc->tfm = tfm;
-		desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 
 		ret = crypto_shash_digest(desc, fw->image, image_size,
 					  hash_data);
diff --git a/drivers/staging/ks7010/ks_hostif.c b/drivers/staging/ks7010/ks_hostif.c
index 06ebea0be118..122d4c0af363 100644
--- a/drivers/staging/ks7010/ks_hostif.c
+++ b/drivers/staging/ks7010/ks_hostif.c
@@ -219,7 +219,6 @@ michael_mic(u8 *key, u8 *data, unsigned int len, u8 priority, u8 *result)
 	}
 
 	desc->tfm = tfm;
-	desc->flags = 0;
 
 	ret = crypto_shash_init(desc);
 	if (ret < 0)
diff --git a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
index 55da8c9dfe50..a084e1501f9d 100644
--- a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
+++ b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
@@ -507,7 +507,6 @@ static int michael_mic(struct crypto_shash *tfm_michael, u8 *key, u8 *hdr,
 	int err;
 
 	desc->tfm = tfm_michael;
-	desc->flags = 0;
 
 	if (crypto_shash_setkey(tfm_michael, key, 8))
 		return -1;
diff --git a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
index 829fa4bd253c..d67bb57994c4 100644
--- a/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
+++ b/drivers/staging/rtl8192u/ieee80211/ieee80211_crypt_tkip.c
@@ -503,7 +503,6 @@ static int michael_mic(struct crypto_shash *tfm_michael, u8 *key, u8 *hdr,
 	int err;
 
 	desc->tfm = tfm_michael;
-	desc->flags = 0;
 
 	if (crypto_shash_setkey(tfm_michael, key, 8))
 		return -1;
diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c
index 4e680d753941..ca7d7e8aecc0 100644
--- a/drivers/target/iscsi/iscsi_target_auth.c
+++ b/drivers/target/iscsi/iscsi_target_auth.c
@@ -252,7 +252,6 @@ static int chap_server_compute_md5(
 	}
 
 	desc->tfm = tfm;
-	desc->flags = 0;
 
 	ret = crypto_shash_init(desc);
 	if (ret < 0) {
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
index 7416bdbd8576..b7980c856898 100644
--- a/drivers/thunderbolt/domain.c
+++ b/drivers/thunderbolt/domain.c
@@ -678,7 +678,6 @@ int tb_domain_challenge_switch_key(struct tb *tb, struct tb_switch *sw)
 	}
 
 	shash->tfm = tfm;
-	shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 
 	memset(hmac, 0, sizeof(hmac));
 	ret = crypto_shash_digest(shash, challenge, sizeof(hmac), hmac);