[PATCH] crypto: sun8i-ss - Remove GFP_DMA and add DMA alignment padding

From: Herbert Xu
Date: Thu Dec 29 2022 - 03:59:08 EST


GFP_DMA does not guarantee that the returned memory is aligned
for DMA. In fact for sun8i-ss it is superfluous and can be removed.

However, kmalloc may start returning DMA-unaligned memory in future
so fix this by adding the alignment by hand.

Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>

diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c
index 902f6be057ec..83c6dfad77e1 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-cipher.c
@@ -452,7 +452,7 @@ int sun8i_ss_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
}
kfree_sensitive(op->key);
op->keylen = keylen;
- op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
+ op->key = kmemdup(key, keylen, GFP_KERNEL);
if (!op->key)
return -ENOMEM;

@@ -475,7 +475,7 @@ int sun8i_ss_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,

kfree_sensitive(op->key);
op->keylen = keylen;
- op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
+ op->key = kmemdup(key, keylen, GFP_KERNEL);
if (!op->key)
return -ENOMEM;

diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
index ac2329e2b0e5..c9dc06f97857 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c
@@ -16,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
+#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
@@ -527,7 +528,7 @@ static int allocate_flows(struct sun8i_ss_dev *ss)
init_completion(&ss->flows[i].complete);

ss->flows[i].biv = devm_kmalloc(ss->dev, AES_BLOCK_SIZE,
- GFP_KERNEL | GFP_DMA);
+ GFP_KERNEL);
if (!ss->flows[i].biv) {
err = -ENOMEM;
goto error_engine;
@@ -535,7 +536,7 @@ static int allocate_flows(struct sun8i_ss_dev *ss)

for (j = 0; j < MAX_SG; j++) {
ss->flows[i].iv[j] = devm_kmalloc(ss->dev, AES_BLOCK_SIZE,
- GFP_KERNEL | GFP_DMA);
+ GFP_KERNEL);
if (!ss->flows[i].iv[j]) {
err = -ENOMEM;
goto error_engine;
@@ -544,13 +545,15 @@ static int allocate_flows(struct sun8i_ss_dev *ss)

/* the padding could be up to two block. */
ss->flows[i].pad = devm_kmalloc(ss->dev, MAX_PAD_SIZE,
- GFP_KERNEL | GFP_DMA);
+ GFP_KERNEL);
if (!ss->flows[i].pad) {
err = -ENOMEM;
goto error_engine;
}
- ss->flows[i].result = devm_kmalloc(ss->dev, SHA256_DIGEST_SIZE,
- GFP_KERNEL | GFP_DMA);
+ ss->flows[i].result =
+ devm_kmalloc(ss->dev, max(SHA256_DIGEST_SIZE,
+ dma_get_cache_alignment()),
+ GFP_KERNEL);
if (!ss->flows[i].result) {
err = -ENOMEM;
goto error_engine;
diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
index 36a82b22953c..577bf636f7fb 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c
@@ -79,10 +79,10 @@ int sun8i_ss_hmac_setkey(struct crypto_ahash *ahash, const u8 *key,
memcpy(tfmctx->key, key, keylen);
}

- tfmctx->ipad = kzalloc(bs, GFP_KERNEL | GFP_DMA);
+ tfmctx->ipad = kzalloc(bs, GFP_KERNEL);
if (!tfmctx->ipad)
return -ENOMEM;
- tfmctx->opad = kzalloc(bs, GFP_KERNEL | GFP_DMA);
+ tfmctx->opad = kzalloc(bs, GFP_KERNEL);
if (!tfmctx->opad) {
ret = -ENOMEM;
goto err_opad;
diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
index dd677e9ed06f..70c7b5d571b8 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
@@ -11,6 +11,8 @@
*/
#include "sun8i-ss.h"
#include <linux/dma-mapping.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
#include <linux/pm_runtime.h>
#include <crypto/internal/rng.h>

@@ -25,7 +27,7 @@ int sun8i_ss_prng_seed(struct crypto_rng *tfm, const u8 *seed,
ctx->seed = NULL;
}
if (!ctx->seed)
- ctx->seed = kmalloc(slen, GFP_KERNEL | GFP_DMA);
+ ctx->seed = kmalloc(slen, GFP_KERNEL);
if (!ctx->seed)
return -ENOMEM;

@@ -58,6 +60,7 @@ int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
struct sun8i_ss_rng_tfm_ctx *ctx = crypto_rng_ctx(tfm);
struct rng_alg *alg = crypto_rng_alg(tfm);
struct sun8i_ss_alg_template *algt;
+ unsigned int todo_with_padding;
struct sun8i_ss_dev *ss;
dma_addr_t dma_iv, dma_dst;
unsigned int todo;
@@ -81,7 +84,11 @@ int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
todo = dlen + PRNG_SEED_SIZE + PRNG_DATA_SIZE;
todo -= todo % PRNG_DATA_SIZE;

- d = kzalloc(todo, GFP_KERNEL | GFP_DMA);
+ todo_with_padding = ALIGN(todo, dma_get_cache_alignment());
+ if (todo_with_padding < todo || todo < dlen)
+ return -EOVERFLOW;
+
+ d = kzalloc(todo_with_padding, GFP_KERNEL);
if (!d)
return -ENOMEM;

--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt