[PATCH v2 17/27] staging: ccree: use array for double buffer

From: Gilad Ben-Yossef
Date: Wed Jan 03 2018 - 08:39:20 EST


The ccree hash code is using a double buffer to hold data
for processing but manages the buffers and their associated
data count in two separate fields and uses a predicate to
chose which to use.

Move to using a proper 2 members array for a much cleaner code.

Signed-off-by: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>
---
drivers/staging/ccree/ssi_buffer_mgr.c | 21 +++++++-------------
drivers/staging/ccree/ssi_hash.c | 36 ++++++++++++++++------------------
drivers/staging/ccree/ssi_hash.h | 26 ++++++++++++++++++++----
3 files changed, 46 insertions(+), 37 deletions(-)

diff --git a/drivers/staging/ccree/ssi_buffer_mgr.c b/drivers/staging/ccree/ssi_buffer_mgr.c
index 9e3f557..9f67bb7 100644
--- a/drivers/staging/ccree/ssi_buffer_mgr.c
+++ b/drivers/staging/ccree/ssi_buffer_mgr.c
@@ -1391,10 +1391,8 @@ int cc_map_hash_request_final(struct cc_drvdata *drvdata, void *ctx,
{
struct ahash_req_ctx *areq_ctx = (struct ahash_req_ctx *)ctx;
struct device *dev = drvdata_to_dev(drvdata);
- u8 *curr_buff = areq_ctx->buff_index ? areq_ctx->buff1 :
- areq_ctx->buff0;
- u32 *curr_buff_cnt = areq_ctx->buff_index ? &areq_ctx->buff1_cnt :
- &areq_ctx->buff0_cnt;
+ u8 *curr_buff = cc_hash_buf(areq_ctx);
+ u32 *curr_buff_cnt = cc_hash_buf_cnt(areq_ctx);
struct mlli_params *mlli_params = &areq_ctx->mlli_params;
struct buffer_array sg_data;
struct buff_mgr_handle *buff_mgr = drvdata->buff_mgr_handle;
@@ -1472,14 +1470,10 @@ int cc_map_hash_request_update(struct cc_drvdata *drvdata, void *ctx,
{
struct ahash_req_ctx *areq_ctx = (struct ahash_req_ctx *)ctx;
struct device *dev = drvdata_to_dev(drvdata);
- u8 *curr_buff = areq_ctx->buff_index ? areq_ctx->buff1 :
- areq_ctx->buff0;
- u32 *curr_buff_cnt = areq_ctx->buff_index ? &areq_ctx->buff1_cnt :
- &areq_ctx->buff0_cnt;
- u8 *next_buff = areq_ctx->buff_index ? areq_ctx->buff0 :
- areq_ctx->buff1;
- u32 *next_buff_cnt = areq_ctx->buff_index ? &areq_ctx->buff0_cnt :
- &areq_ctx->buff1_cnt;
+ u8 *curr_buff = cc_hash_buf(areq_ctx);
+ u32 *curr_buff_cnt = cc_hash_buf_cnt(areq_ctx);
+ u8 *next_buff = cc_next_buf(areq_ctx);
+ u32 *next_buff_cnt = cc_next_buf_cnt(areq_ctx);
struct mlli_params *mlli_params = &areq_ctx->mlli_params;
unsigned int update_data_len;
u32 total_in_len = nbytes + *curr_buff_cnt;
@@ -1585,8 +1579,7 @@ void cc_unmap_hash_request(struct device *dev, void *ctx,
struct scatterlist *src, bool do_revert)
{
struct ahash_req_ctx *areq_ctx = (struct ahash_req_ctx *)ctx;
- u32 *prev_len = areq_ctx->buff_index ? &areq_ctx->buff0_cnt :
- &areq_ctx->buff1_cnt;
+ u32 *prev_len = cc_next_buf_cnt(areq_ctx);

/*In case a pool was set, a table was
*allocated and should be released
diff --git a/drivers/staging/ccree/ssi_hash.c b/drivers/staging/ccree/ssi_hash.c
index 4e11b5d..a8ea6a2 100644
--- a/drivers/staging/ccree/ssi_hash.c
+++ b/drivers/staging/ccree/ssi_hash.c
@@ -129,12 +129,12 @@ static int cc_map_req(struct device *dev, struct ahash_req_ctx *state,
bool is_hmac = ctx->is_hmac;
int rc = -ENOMEM;

- state->buff0 = kzalloc(CC_MAX_HASH_BLCK_SIZE, flags);
- if (!state->buff0)
+ state->buffers[0] = kzalloc(CC_MAX_HASH_BLCK_SIZE, flags);
+ if (!state->buffers[0])
goto fail0;

- state->buff1 = kzalloc(CC_MAX_HASH_BLCK_SIZE, flags);
- if (!state->buff1)
+ state->buffers[1] = kzalloc(CC_MAX_HASH_BLCK_SIZE, flags);
+ if (!state->buffers[1])
goto fail_buff0;

state->digest_result_buff = kzalloc(CC_MAX_HASH_DIGEST_SIZE, flags);
@@ -252,8 +252,8 @@ static int cc_map_req(struct device *dev, struct ahash_req_ctx *state,
} else {
state->opad_digest_dma_addr = 0;
}
- state->buff0_cnt = 0;
- state->buff1_cnt = 0;
+ state->buf_cnt[0] = 0;
+ state->buf_cnt[1] = 0;
state->buff_index = 0;
state->mlli_params.curr_pool = NULL;

@@ -281,11 +281,11 @@ static int cc_map_req(struct device *dev, struct ahash_req_ctx *state,
kfree(state->digest_result_buff);
state->digest_result_buff = NULL;
fail_buff1:
- kfree(state->buff1);
- state->buff1 = NULL;
+ kfree(state->buffers[1]);
+ state->buffers[1] = NULL;
fail_buff0:
- kfree(state->buff0);
- state->buff0 = NULL;
+ kfree(state->buffers[0]);
+ state->buffers[0] = NULL;
fail0:
return rc;
}
@@ -319,8 +319,8 @@ static void cc_unmap_req(struct device *dev, struct ahash_req_ctx *state,
kfree(state->digest_bytes_len);
kfree(state->digest_buff);
kfree(state->digest_result_buff);
- kfree(state->buff1);
- kfree(state->buff0);
+ kfree(state->buffers[1]);
+ kfree(state->buffers[0]);
}

static void cc_unmap_result(struct device *dev, struct ahash_req_ctx *state,
@@ -1375,8 +1375,7 @@ static int cc_mac_final(struct ahash_request *req)
u32 key_size, key_len;
u32 digestsize = crypto_ahash_digestsize(tfm);
gfp_t flags = cc_gfp_flags(&req->base);
- u32 rem_cnt = state->buff_index ? state->buff1_cnt :
- state->buff0_cnt;
+ u32 rem_cnt = *cc_hash_buf_cnt(state);

if (ctx->hw_mode == DRV_CIPHER_XCBC_MAC) {
key_size = CC_AES_128_BIT_KEY_SIZE;
@@ -1630,9 +1629,8 @@ static int cc_hash_export(struct ahash_request *req, void *out)
struct cc_hash_ctx *ctx = crypto_ahash_ctx(ahash);
struct device *dev = drvdata_to_dev(ctx->drvdata);
struct ahash_req_ctx *state = ahash_request_ctx(req);
- u8 *curr_buff = state->buff_index ? state->buff1 : state->buff0;
- u32 curr_buff_cnt = state->buff_index ? state->buff1_cnt :
- state->buff0_cnt;
+ u8 *curr_buff = cc_hash_buf(state);
+ u32 curr_buff_cnt = *cc_hash_buf_cnt(state);
const u32 tmp = CC_EXPORT_MAGIC;

memcpy(out, &tmp, sizeof(u32));
@@ -1715,8 +1713,8 @@ static int cc_hash_import(struct ahash_request *req, const void *in)
}
in += sizeof(u32);

- state->buff0_cnt = tmp;
- memcpy(state->buff0, in, state->buff0_cnt);
+ state->buf_cnt[0] = tmp;
+ memcpy(state->buffers[0], in, tmp);

out:
return rc;
diff --git a/drivers/staging/ccree/ssi_hash.h b/drivers/staging/ccree/ssi_hash.h
index 484cbb4..78f193b 100644
--- a/drivers/staging/ccree/ssi_hash.h
+++ b/drivers/staging/ccree/ssi_hash.h
@@ -39,8 +39,7 @@ struct aeshash_state {

/* ahash state */
struct ahash_req_ctx {
- u8 *buff0;
- u8 *buff1;
+ u8 *buffers[2];
u8 *digest_result_buff;
struct async_gen_req_ctx gen_ctx;
enum cc_req_dma_buf_type data_dma_buf_type;
@@ -51,8 +50,7 @@ struct ahash_req_ctx {
dma_addr_t digest_buff_dma_addr;
dma_addr_t digest_bytes_len_dma_addr;
dma_addr_t digest_result_dma_addr;
- u32 buff0_cnt;
- u32 buff1_cnt;
+ u32 buf_cnt[2];
u32 buff_index;
u32 xcbc_count; /* count xcbc update operatations */
struct scatterlist buff_sg[2];
@@ -62,6 +60,26 @@ struct ahash_req_ctx {
struct mlli_params mlli_params;
};

+static inline u32 *cc_hash_buf_cnt(struct ahash_req_ctx *state)
+{
+ return &state->buf_cnt[state->buff_index];
+}
+
+static inline u8 *cc_hash_buf(struct ahash_req_ctx *state)
+{
+ return state->buffers[state->buff_index];
+}
+
+static inline u32 *cc_next_buf_cnt(struct ahash_req_ctx *state)
+{
+ return &state->buf_cnt[state->buff_index ^ 1];
+}
+
+static inline u8 *cc_next_buf(struct ahash_req_ctx *state)
+{
+ return state->buffers[state->buff_index ^ 1];
+}
+
int cc_hash_alloc(struct cc_drvdata *drvdata);
int cc_init_hash_sram(struct cc_drvdata *drvdata);
int cc_hash_free(struct cc_drvdata *drvdata);
--
2.7.4