Subject: [patch 83/88] crypto: ixp4xx - Fix handling of chained sg buffers - msg#14670

2.6.28-stable review patch. If anyone has any objections, please let us know.

------------------

From: Christian Hohnstaedt <chohnstaedt@xxxxxxxxxxxxxx>

commit 0d44dc59b2b434b29aafeae581d06f81efac7c83 upstream.

- keep dma functions away from chained scatterlists.
Use the existing scatterlist iteration inside the driver
to call dma_map_single() for each chunk and avoid dma_map_sg().

Signed-off-by: Christian Hohnstaedt <chohnstaedt@xxxxxxxxxxxxxx>
Tested-By: Karl Hiramoto <karl@xxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/crypto/ixp4xx_crypto.c | 184 ++++++++++++++---------------------------
1 file changed, 64 insertions(+), 120 deletions(-)

--- a/drivers/crypto/ixp4xx_crypto.c
+++ b/drivers/crypto/ixp4xx_crypto.c
@@ -101,6 +101,7 @@ struct buffer_desc {
u32 phys_addr;
u32 __reserved[4];
struct buffer_desc *next;
+ enum dma_data_direction dir;
};

struct crypt_ctl {
@@ -132,14 +133,10 @@ struct crypt_ctl {
struct ablk_ctx {
struct buffer_desc *src;
struct buffer_desc *dst;
- unsigned src_nents;
- unsigned dst_nents;
};

struct aead_ctx {
struct buffer_desc *buffer;
- unsigned short assoc_nents;
- unsigned short src_nents;
struct scatterlist ivlist;
/* used when the hmac is not on one sg entry */
u8 *hmac_virt;
@@ -312,7 +309,7 @@ static struct crypt_ctl *get_crypt_desc_
}
}

-static void free_buf_chain(struct buffer_desc *buf, u32 phys)
+static void free_buf_chain(struct device *dev, struct buffer_desc *buf,u32
phys)
{
while (buf) {
struct buffer_desc *buf1;
@@ -320,6 +317,7 @@ static void free_buf_chain(struct buffer

buf1 = buf->next;
phys1 = buf->phys_next;
+ dma_unmap_single(dev, buf->phys_next, buf->buf_len, buf->dir);
dma_pool_free(buffer_pool, buf, phys);
buf = buf1;
phys = phys1;
@@ -348,7 +346,6 @@ static void one_packet(dma_addr_t phys)
struct crypt_ctl *crypt;
struct ixp_ctx *ctx;
int failed;
- enum dma_data_direction src_direction = DMA_BIDIRECTIONAL;

failed = phys & 0x1 ? -EBADMSG : 0;
phys &= ~0x3;
@@ -358,13 +355,8 @@ static void one_packet(dma_addr_t phys)
case CTL_FLAG_PERFORM_AEAD: {
struct aead_request *req = crypt->data.aead_req;
struct aead_ctx *req_ctx = aead_request_ctx(req);
- dma_unmap_sg(dev, req->assoc, req_ctx->assoc_nents,
- DMA_TO_DEVICE);
- dma_unmap_sg(dev, &req_ctx->ivlist, 1, DMA_BIDIRECTIONAL);
- dma_unmap_sg(dev, req->src, req_ctx->src_nents,
- DMA_BIDIRECTIONAL);

- free_buf_chain(req_ctx->buffer, crypt->src_buf);
+ free_buf_chain(dev, req_ctx->buffer, crypt->src_buf);
if (req_ctx->hmac_virt) {
finish_scattered_hmac(crypt);
}
@@ -374,16 +366,11 @@ static void one_packet(dma_addr_t phys)
case CTL_FLAG_PERFORM_ABLK: {
struct ablkcipher_request *req = crypt->data.ablk_req;
struct ablk_ctx *req_ctx = ablkcipher_request_ctx(req);
- int nents;
+
if (req_ctx->dst) {
- nents = req_ctx->dst_nents;
- dma_unmap_sg(dev, req->dst, nents, DMA_FROM_DEVICE);
- free_buf_chain(req_ctx->dst, crypt->dst_buf);
- src_direction = DMA_TO_DEVICE;
- }
- nents = req_ctx->src_nents;
- dma_unmap_sg(dev, req->src, nents, src_direction);
- free_buf_chain(req_ctx->src, crypt->src_buf);
+ free_buf_chain(dev, req_ctx->dst, crypt->dst_buf);
+ }
+ free_buf_chain(dev, req_ctx->src, crypt->src_buf);
req->base.complete(&req->base, failed);
break;
}
@@ -748,56 +735,35 @@ static int setup_cipher(struct crypto_tf
return 0;
}

-static int count_sg(struct scatterlist *sg, int nbytes)
-{
- int i;
- for (i = 0; nbytes > 0; i++, sg = sg_next(sg))
- nbytes -= sg->length;
- return i;
-}
-
-static struct buffer_desc *chainup_buffers(struct scatterlist *sg,
- unsigned nbytes, struct buffer_desc *buf, gfp_t flags)
+static struct buffer_desc *chainup_buffers(struct device *dev,
+ struct scatterlist *sg, unsigned nbytes,
+ struct buffer_desc *buf, gfp_t flags,
+ enum dma_data_direction dir)
{
- int nents = 0;
-
- while (nbytes > 0) {
+ for (;nbytes > 0; sg = scatterwalk_sg_next(sg)) {
+ unsigned len = min(nbytes, sg->length);
struct buffer_desc *next_buf;
u32 next_buf_phys;
- unsigned len = min(nbytes, sg_dma_len(sg));
+ void *ptr;

- nents++;
nbytes -= len;
- if (!buf->phys_addr) {
- buf->phys_addr = sg_dma_address(sg);
- buf->buf_len = len;
- buf->next = NULL;
- buf->phys_next = 0;
- goto next;
- }
- /* Two consecutive chunks on one page may be handled by the old
- * buffer descriptor, increased by the length of the new one
- */
- if (sg_dma_address(sg) == buf->phys_addr + buf->buf_len) {
- buf->buf_len += len;
- goto next;
- }
+ ptr = page_address(sg_page(sg)) + sg->offset;
next_buf = dma_pool_alloc(buffer_pool, flags, &next_buf_phys);
- if (!next_buf)
- return NULL;
+ if (!next_buf) {
+ buf = NULL;
+ break;
+ }
+ sg_dma_address(sg) = dma_map_single(dev, ptr, len, dir);
buf->next = next_buf;
buf->phys_next = next_buf_phys;
-
buf = next_buf;
- buf->next = NULL;
- buf->phys_next = 0;
+
buf->phys_addr = sg_dma_address(sg);
buf->buf_len = len;
-next:
- if (nbytes > 0) {
- sg = sg_next(sg);
- }
+ buf->dir = dir;
}
+ buf->next = NULL;
+ buf->phys_next = 0;
return buf;
}

@@ -858,12 +824,12 @@ static int ablk_perform(struct ablkciphe
struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
struct ixp_ctx *ctx = crypto_ablkcipher_ctx(tfm);
unsigned ivsize = crypto_ablkcipher_ivsize(tfm);
- int ret = -ENOMEM;
struct ix_sa_dir *dir;
struct crypt_ctl *crypt;
- unsigned int nbytes = req->nbytes, nents;
+ unsigned int nbytes = req->nbytes;
enum dma_data_direction src_direction = DMA_BIDIRECTIONAL;
struct ablk_ctx *req_ctx = ablkcipher_request_ctx(req);
+ struct buffer_desc src_hook;
gfp_t flags = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
GFP_KERNEL : GFP_ATOMIC;

@@ -876,7 +842,7 @@ static int ablk_perform(struct ablkciphe

crypt = get_crypt_desc();
if (!crypt)
- return ret;
+ return -ENOMEM;

crypt->data.ablk_req = req;
crypt->crypto_ctx = dir->npe_ctx_phys;
@@ -889,53 +855,41 @@ static int ablk_perform(struct ablkciphe
BUG_ON(ivsize && !req->info);
memcpy(crypt->iv, req->info, ivsize);
if (req->src != req->dst) {
+ struct buffer_desc dst_hook;
crypt->mode |= NPE_OP_NOT_IN_PLACE;
- nents = count_sg(req->dst, nbytes);
/* This was never tested by Intel
* for more than one dst buffer, I think. */
- BUG_ON(nents != 1);
- req_ctx->dst_nents = nents;
- dma_map_sg(dev, req->dst, nents, DMA_FROM_DEVICE);
- req_ctx->dst = dma_pool_alloc(buffer_pool,
flags,&crypt->dst_buf);
- if (!req_ctx->dst)
- goto unmap_sg_dest;
- req_ctx->dst->phys_addr = 0;
- if (!chainup_buffers(req->dst, nbytes, req_ctx->dst, flags))
+ BUG_ON(req->dst->length < nbytes);
+ req_ctx->dst = NULL;
+ if (!chainup_buffers(dev, req->dst, nbytes, &dst_hook,
+ flags, DMA_FROM_DEVICE))
goto free_buf_dest;
src_direction = DMA_TO_DEVICE;
+ req_ctx->dst = dst_hook.next;
+ crypt->dst_buf = dst_hook.phys_next;
} else {
req_ctx->dst = NULL;
- req_ctx->dst_nents = 0;
}
- nents = count_sg(req->src, nbytes);
- req_ctx->src_nents = nents;
- dma_map_sg(dev, req->src, nents, src_direction);
-
- req_ctx->src = dma_pool_alloc(buffer_pool, flags, &crypt->src_buf);
- if (!req_ctx->src)
- goto unmap_sg_src;
- req_ctx->src->phys_addr = 0;
- if (!chainup_buffers(req->src, nbytes, req_ctx->src, flags))
+ req_ctx->src = NULL;
+ if (!chainup_buffers(dev, req->src, nbytes, &src_hook,
+ flags, src_direction))
goto free_buf_src;

+ req_ctx->src = src_hook.next;
+ crypt->src_buf = src_hook.phys_next;
crypt->ctl_flags |= CTL_FLAG_PERFORM_ABLK;
qmgr_put_entry(SEND_QID, crypt_virt2phys(crypt));
BUG_ON(qmgr_stat_overflow(SEND_QID));
return -EINPROGRESS;

free_buf_src:
- free_buf_chain(req_ctx->src, crypt->src_buf);
-unmap_sg_src:
- dma_unmap_sg(dev, req->src, req_ctx->src_nents, src_direction);
+ free_buf_chain(dev, req_ctx->src, crypt->src_buf);
free_buf_dest:
if (req->src != req->dst) {
- free_buf_chain(req_ctx->dst, crypt->dst_buf);
-unmap_sg_dest:
- dma_unmap_sg(dev, req->src, req_ctx->dst_nents,
- DMA_FROM_DEVICE);
+ free_buf_chain(dev, req_ctx->dst, crypt->dst_buf);
}
crypt->ctl_flags = CTL_FLAG_UNUSED;
- return ret;
+ return -ENOMEM;
}

static int ablk_encrypt(struct ablkcipher_request *req)
@@ -983,7 +937,7 @@ static int hmac_inconsistent(struct scat
break;

offset += sg->length;
- sg = sg_next(sg);
+ sg = scatterwalk_sg_next(sg);
}
return (start + nbytes > offset + sg->length);
}
@@ -995,11 +949,10 @@ static int aead_perform(struct aead_requ
struct ixp_ctx *ctx = crypto_aead_ctx(tfm);
unsigned ivsize = crypto_aead_ivsize(tfm);
unsigned authsize = crypto_aead_authsize(tfm);
- int ret = -ENOMEM;
struct ix_sa_dir *dir;
struct crypt_ctl *crypt;
- unsigned int cryptlen, nents;
- struct buffer_desc *buf;
+ unsigned int cryptlen;
+ struct buffer_desc *buf, src_hook;
struct aead_ctx *req_ctx = aead_request_ctx(req);
gfp_t flags = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
GFP_KERNEL : GFP_ATOMIC;
@@ -1020,7 +973,7 @@ static int aead_perform(struct aead_requ
}
crypt = get_crypt_desc();
if (!crypt)
- return ret;
+ return -ENOMEM;

crypt->data.aead_req = req;
crypt->crypto_ctx = dir->npe_ctx_phys;
@@ -1039,31 +992,27 @@ static int aead_perform(struct aead_requ
BUG(); /* -ENOTSUP because of my lazyness */
}

- req_ctx->buffer = dma_pool_alloc(buffer_pool, flags, &crypt->src_buf);
- if (!req_ctx->buffer)
- goto out;
- req_ctx->buffer->phys_addr = 0;
/* ASSOC data */
- nents = count_sg(req->assoc, req->assoclen);
- req_ctx->assoc_nents = nents;
- dma_map_sg(dev, req->assoc, nents, DMA_TO_DEVICE);
- buf = chainup_buffers(req->assoc, req->assoclen, req_ctx->buffer,flags);
+ buf = chainup_buffers(dev, req->assoc, req->assoclen, &src_hook,
+ flags, DMA_TO_DEVICE);
+ req_ctx->buffer = src_hook.next;
+ crypt->src_buf = src_hook.phys_next;
if (!buf)
- goto unmap_sg_assoc;
+ goto out;
/* IV */
sg_init_table(&req_ctx->ivlist, 1);
sg_set_buf(&req_ctx->ivlist, iv, ivsize);
- dma_map_sg(dev, &req_ctx->ivlist, 1, DMA_BIDIRECTIONAL);
- buf = chainup_buffers(&req_ctx->ivlist, ivsize, buf, flags);
+ buf = chainup_buffers(dev, &req_ctx->ivlist, ivsize, buf, flags,
+ DMA_BIDIRECTIONAL);
if (!buf)
- goto unmap_sg_iv;
+ goto free_chain;
if (unlikely(hmac_inconsistent(req->src, cryptlen, authsize))) {
/* The 12 hmac bytes are scattered,
* we need to copy them into a safe buffer */
req_ctx->hmac_virt = dma_pool_alloc(buffer_pool, flags,
&crypt->icv_rev_aes);
if (unlikely(!req_ctx->hmac_virt))
- goto unmap_sg_iv;
+ goto free_chain;
if (!encrypt) {
scatterwalk_map_and_copy(req_ctx->hmac_virt,
req->src, cryptlen, authsize, 0);
@@ -1073,33 +1022,28 @@ static int aead_perform(struct aead_requ
req_ctx->hmac_virt = NULL;
}
/* Crypt */
- nents = count_sg(req->src, cryptlen + authsize);
- req_ctx->src_nents = nents;
- dma_map_sg(dev, req->src, nents, DMA_BIDIRECTIONAL);
- buf = chainup_buffers(req->src, cryptlen + authsize, buf, flags);
+ buf = chainup_buffers(dev, req->src, cryptlen + authsize, buf, flags,
+ DMA_BIDIRECTIONAL);
if (!buf)
- goto unmap_sg_src;
+ goto free_hmac_virt;
if (!req_ctx->hmac_virt) {
crypt->icv_rev_aes = buf->phys_addr + buf->buf_len - authsize;
}
+
crypt->ctl_flags |= CTL_FLAG_PERFORM_AEAD;
qmgr_put_entry(SEND_QID, crypt_virt2phys(crypt));
BUG_ON(qmgr_stat_overflow(SEND_QID));
return -EINPROGRESS;
-unmap_sg_src:
- dma_unmap_sg(dev, req->src, req_ctx->src_nents, DMA_BIDIRECTIONAL);
+free_hmac_virt:
if (req_ctx->hmac_virt) {
dma_pool_free(buffer_pool, req_ctx->hmac_virt,
crypt->icv_rev_aes);
}
-unmap_sg_iv:
- dma_unmap_sg(dev, &req_ctx->ivlist, 1, DMA_BIDIRECTIONAL);
-unmap_sg_assoc:
- dma_unmap_sg(dev, req->assoc, req_ctx->assoc_nents, DMA_TO_DEVICE);
- free_buf_chain(req_ctx->buffer, crypt->src_buf);
+free_chain:
+ free_buf_chain(dev, req_ctx->buffer, crypt->src_buf);
out:
crypt->ctl_flags = CTL_FLAG_UNUSED;
- return ret;
+ return -ENOMEM;
}

static int aead_setup(struct crypto_aead *tfm, unsigned int authsize)


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