crypto: omap-sham - crypto_ahash_final() now not need to be called.

According to the Herbert Xu, client may not always call
crypto_ahash_final().

In the case of error in hash calculation resources will be
automatically cleaned up.

But if no hash calculation error happens and client will not call
crypto_ahash_final() at all, then internal buffer will not be freed,
and clocks will not be disabled.

This patch provides support for atomic crypto_ahash_update() call.
Clocks are now enabled and disabled per update request.

Data buffer is now allocated as a part of request context.
Client is obligated to free it with crypto_free_ahash().

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
index 6340c5ef4712c8cb02b86b4f49a1affb83e25a2b..85d627774538146b4ca8893d451b62975c3688a9 100644 (file)
--- a/drivers/crypto/omap-sham.c
+++ b/drivers/crypto/omap-sham.c
@@ -89,6 +89,11 @@
 #define OP_UPDATE      1
 #define OP_FINAL       2
 
+#define OMAP_ALIGN_MASK                (sizeof(u32)-1)
+#define OMAP_ALIGNED           __attribute__((aligned(sizeof(u32))))
+
+#define BUFLEN         PAGE_SIZE
+
 struct omap_sham_dev;
 
 struct omap_sham_reqctx {
@@ -96,9 +101,8 @@ struct omap_sham_reqctx {
        unsigned long           flags;
        unsigned long           op;
 
-       u8                      digest[SHA1_DIGEST_SIZE];
+       u8                      digest[SHA1_DIGEST_SIZE] OMAP_ALIGNED;
        size_t                  digcnt;
-       u8                      *buffer;
        size_t                  bufcnt;
        size_t                  buflen;
        dma_addr_t              dma_addr;
@@ -107,6 +111,8 @@ struct omap_sham_reqctx {
        struct scatterlist      *sg;
        unsigned int            offset; /* offset in current sg */
        unsigned int            total;  /* total request */
+
+       u8                      buffer[0] OMAP_ALIGNED;
 };
 
 struct omap_sham_hmac_ctx {
@@ -219,31 +225,33 @@ static void omap_sham_copy_hash(struct ahash_request *req, int out)
        }
 }
 
-static int omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
-                                int final, int dma)
+static int omap_sham_hw_init(struct omap_sham_dev *dd)
 {
-       struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
-       u32 val = length << 5, mask;
+       clk_enable(dd->iclk);
 
-       if (unlikely(!ctx->digcnt)) {
+       if (!(dd->flags & FLAGS_INIT)) {
+               omap_sham_write_mask(dd, SHA_REG_MASK,
+                       SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);
 
-               clk_enable(dd->iclk);
+               if (omap_sham_wait(dd, SHA_REG_SYSSTATUS,
+                                       SHA_REG_SYSSTATUS_RESETDONE))
+                       return -ETIMEDOUT;
 
-               if (!(dd->flags & FLAGS_INIT)) {
-                       omap_sham_write_mask(dd, SHA_REG_MASK,
-                               SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);
+               dd->flags |= FLAGS_INIT;
+               dd->err = 0;
+       }
 
-                       if (omap_sham_wait(dd, SHA_REG_SYSSTATUS,
-                                               SHA_REG_SYSSTATUS_RESETDONE)) {
-                               clk_disable(dd->iclk);
-                               return -ETIMEDOUT;
-                       }
-                       dd->flags |= FLAGS_INIT;
-                       dd->err = 0;
-               }
-       } else {
+       return 0;
+}
+
+static void omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
+                                int final, int dma)
+{
+       struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
+       u32 val = length << 5, mask;
+
+       if (likely(ctx->digcnt))
                omap_sham_write(dd, SHA_REG_DIGCNT, ctx->digcnt);
-       }
 
        omap_sham_write_mask(dd, SHA_REG_MASK,
                SHA_REG_MASK_IT_EN | (dma ? SHA_REG_MASK_DMA_EN : 0),
@@ -263,23 +271,19 @@ static int omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
                        SHA_REG_CTRL_ALGO | SHA_REG_CTRL_LENGTH;
 
        omap_sham_write_mask(dd, SHA_REG_CTRL, val, mask);
-
-       return 0;
 }
 
 static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf,
                              size_t length, int final)
 {
        struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
-       int err, count, len32;
+       int count, len32;
        const u32 *buffer = (const u32 *)buf;
 
        dev_dbg(dd->dev, "xmit_cpu: digcnt: %d, length: %d, final: %d\n",
                                                ctx->digcnt, length, final);
 
-       err = omap_sham_write_ctrl(dd, length, final, 0);
-       if (err)
-               return err;
+       omap_sham_write_ctrl(dd, length, final, 0);
 
        /* should be non-zero before next lines to disable clocks later */
        ctx->digcnt += length;
@@ -302,14 +306,10 @@ static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
                              size_t length, int final)
 {
        struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
-       int err, len32;
+       int len32;
 
        dev_dbg(dd->dev, "xmit_dma: digcnt: %d, length: %d, final: %d\n",
                                                ctx->digcnt, length, final);
-       /* flush cache entries related to our page */
-       if (dma_addr == ctx->dma_addr)
-               dma_sync_single_for_device(dd->dev, dma_addr, length,
-                                          DMA_TO_DEVICE);
 
        len32 = DIV_ROUND_UP(length, sizeof(u32));
 
@@ -320,19 +320,7 @@ static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
        omap_set_dma_src_params(dd->dma_lch, 0, OMAP_DMA_AMODE_POST_INC,
                                dma_addr, 0, 0);
 
-       omap_set_dma_dest_params(dd->dma_lch, 0,
-                       OMAP_DMA_AMODE_CONSTANT,
-                       dd->phys_base + SHA_REG_DIN(0), 0, 16);
-
-       omap_set_dma_dest_burst_mode(dd->dma_lch,
-                       OMAP_DMA_DATA_BURST_16);
-
-       omap_set_dma_src_burst_mode(dd->dma_lch,
-                       OMAP_DMA_DATA_BURST_4);
-
-       err = omap_sham_write_ctrl(dd, length, final, 1);
-       if (err)
-               return err;
+       omap_sham_write_ctrl(dd, length, final, 1);
 
        ctx->digcnt += length;
 
@@ -384,6 +372,21 @@ static size_t omap_sham_append_sg(struct omap_sham_reqctx *ctx)
        return 0;
 }
 
+static int omap_sham_xmit_dma_map(struct omap_sham_dev *dd,
+                                       struct omap_sham_reqctx *ctx,
+                                       size_t length, int final)
+{
+       ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer, ctx->buflen,
+                                      DMA_TO_DEVICE);
+       if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
+               dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen);
+               return -EINVAL;
+       }
+
+       /* next call does not fail... so no unmap in the case of error */
+       return omap_sham_xmit_dma(dd, ctx->dma_addr, length, final);
+}
+
 static int omap_sham_update_dma_slow(struct omap_sham_dev *dd)
 {
        struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
@@ -403,7 +406,7 @@ static int omap_sham_update_dma_slow(struct omap_sham_dev *dd)
        if (final || (ctx->bufcnt == ctx->buflen && ctx->total)) {
                count = ctx->bufcnt;
                ctx->bufcnt = 0;
-               return omap_sham_xmit_dma(dd, ctx->dma_addr, count, final);
+               return omap_sham_xmit_dma_map(dd, ctx, count, final);
        }
 
        return 0;
@@ -413,7 +416,6 @@ static int omap_sham_update_dma_fast(struct omap_sham_dev *dd)
 {
        struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
        unsigned int length;
-       int err;
 
        ctx->flags |= FLAGS_FAST;
 
@@ -427,11 +429,8 @@ static int omap_sham_update_dma_fast(struct omap_sham_dev *dd)
 
        ctx->total -= length;
 
-       err = omap_sham_xmit_dma(dd, sg_dma_address(ctx->sg), length, 1);
-       if (err != -EINPROGRESS)
-               dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
-
-       return err;
+       /* next call does not fail... so no unmap in the case of error */
+       return omap_sham_xmit_dma(dd, sg_dma_address(ctx->sg), length, 1);
 }
 
 static int omap_sham_update_cpu(struct omap_sham_dev *dd)
@@ -453,6 +452,9 @@ static int omap_sham_update_dma_stop(struct omap_sham_dev *dd)
        omap_stop_dma(dd->dma_lch);
        if (ctx->flags & FLAGS_FAST)
                dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
+       else
+               dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen,
+                                DMA_TO_DEVICE);
 
        return 0;
 }
@@ -471,18 +473,9 @@ static void omap_sham_cleanup(struct ahash_request *req)
        ctx->flags |= FLAGS_CLEAN;
        spin_unlock_irqrestore(&dd->lock, flags);
 
-       if (ctx->digcnt) {
-               clk_disable(dd->iclk);
+       if (ctx->digcnt)
                memcpy(req->result, ctx->digest, (ctx->flags & FLAGS_SHA1) ?
                                SHA1_DIGEST_SIZE : MD5_DIGEST_SIZE);
-       }
-
-       if (ctx->dma_addr)
-               dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen,
-                                DMA_TO_DEVICE);
-
-       if (ctx->buffer)
-               free_page((unsigned long)ctx->buffer);
 
        dev_dbg(dd->dev, "digcnt: %d, bufcnt: %d\n", ctx->digcnt, ctx->bufcnt);
 }
@@ -520,21 +513,7 @@ static int omap_sham_init(struct ahash_request *req)
 
        ctx->bufcnt = 0;
        ctx->digcnt = 0;
-
-       ctx->buflen = PAGE_SIZE;
-       ctx->buffer = (void *)__get_free_page(
-                               (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
-                               GFP_KERNEL : GFP_ATOMIC);
-       if (!ctx->buffer)
-               return -ENOMEM;
-
-       ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer, ctx->buflen,
-                                       DMA_TO_DEVICE);
-       if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
-               dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen);
-               free_page((unsigned long)ctx->buffer);
-               return -EINVAL;
-       }
+       ctx->buflen = BUFLEN;
 
        if (tctx->flags & FLAGS_HMAC) {
                struct omap_sham_hmac_ctx *bctx = tctx->base;
@@ -581,7 +560,7 @@ static int omap_sham_final_req(struct omap_sham_dev *dd)
                use_dma = 0;
 
        if (use_dma)
-               err = omap_sham_xmit_dma(dd, ctx->dma_addr, ctx->bufcnt, 1);
+               err = omap_sham_xmit_dma_map(dd, ctx, ctx->bufcnt, 1);
        else
                err = omap_sham_xmit_cpu(dd, ctx->buffer, ctx->bufcnt, 1);
 
@@ -615,6 +594,7 @@ static int omap_sham_finish_req_hmac(struct ahash_request *req)
 static void omap_sham_finish_req(struct ahash_request *req, int err)
 {
        struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
+       struct omap_sham_dev *dd = ctx->dd;
 
        if (!err) {
                omap_sham_copy_hash(ctx->dd->req, 1);
@@ -627,7 +607,8 @@ static void omap_sham_finish_req(struct ahash_request *req, int err)
        if ((ctx->flags & FLAGS_FINAL) || err)
                omap_sham_cleanup(req);
 
-       ctx->dd->flags &= ~FLAGS_BUSY;
+       clk_disable(dd->iclk);
+       dd->flags &= ~FLAGS_BUSY;
 
        if (req->base.complete)
                req->base.complete(&req->base, err);
@@ -636,7 +617,7 @@ static void omap_sham_finish_req(struct ahash_request *req, int err)
 static int omap_sham_handle_queue(struct omap_sham_dev *dd,
                                  struct ahash_request *req)
 {
-       struct crypto_async_request *async_req, *backlog;
+       struct crypto_async_request *async_req, *backlog = 0;
        struct omap_sham_reqctx *ctx;
        struct ahash_request *prev_req;
        unsigned long flags;
@@ -672,7 +653,22 @@ static int omap_sham_handle_queue(struct omap_sham_dev *dd,
        dev_dbg(dd->dev, "handling new req, op: %lu, nbytes: %d\n",
                                                ctx->op, req->nbytes);
 
-       if (req != prev_req && ctx->digcnt)
+
+       err = omap_sham_hw_init(dd);
+       if (err)
+               goto err1;
+
+       omap_set_dma_dest_params(dd->dma_lch, 0,
+                       OMAP_DMA_AMODE_CONSTANT,
+                       dd->phys_base + SHA_REG_DIN(0), 0, 16);
+
+       omap_set_dma_dest_burst_mode(dd->dma_lch,
+                       OMAP_DMA_DATA_BURST_16);
+
+       omap_set_dma_src_burst_mode(dd->dma_lch,
+                       OMAP_DMA_DATA_BURST_4);
+
+       if (ctx->digcnt)
                /* request has changed - restore hash */
                omap_sham_copy_hash(req, 0);
 
@@ -684,7 +680,7 @@ static int omap_sham_handle_queue(struct omap_sham_dev *dd,
        } else if (ctx->op == OP_FINAL) {
                err = omap_sham_final_req(dd);
        }
-
+err1:
        if (err != -EINPROGRESS) {
                /* done_task will not finish it, so do it here */
                omap_sham_finish_req(req, err);
@@ -868,7 +864,7 @@ static int omap_sham_cra_init_alg(struct crypto_tfm *tfm, const char *alg_base)
        }
 
        crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
-                                sizeof(struct omap_sham_reqctx));
+                                sizeof(struct omap_sham_reqctx) + BUFLEN);
 
        if (alg_base) {
                struct omap_sham_hmac_ctx *bctx = tctx->base;
@@ -954,7 +950,7 @@ static struct ahash_alg algs[] = {
                                                CRYPTO_ALG_NEED_FALLBACK,
                .cra_blocksize          = SHA1_BLOCK_SIZE,
                .cra_ctxsize            = sizeof(struct omap_sham_ctx),
-               .cra_alignmask          = 0,
+               .cra_alignmask          = OMAP_ALIGN_MASK,
                .cra_module             = THIS_MODULE,
                .cra_init               = omap_sham_cra_init,
                .cra_exit               = omap_sham_cra_exit,
@@ -978,7 +974,7 @@ static struct ahash_alg algs[] = {
                .cra_blocksize          = SHA1_BLOCK_SIZE,
                .cra_ctxsize            = sizeof(struct omap_sham_ctx) +
                                        sizeof(struct omap_sham_hmac_ctx),
-               .cra_alignmask          = 0,
+               .cra_alignmask          = OMAP_ALIGN_MASK,
                .cra_module             = THIS_MODULE,
                .cra_init               = omap_sham_cra_sha1_init,
                .cra_exit               = omap_sham_cra_exit,
@@ -1002,7 +998,7 @@ static struct ahash_alg algs[] = {
                .cra_blocksize          = SHA1_BLOCK_SIZE,
                .cra_ctxsize            = sizeof(struct omap_sham_ctx) +
                                        sizeof(struct omap_sham_hmac_ctx),
-               .cra_alignmask          = 0,
+               .cra_alignmask          = OMAP_ALIGN_MASK,
                .cra_module             = THIS_MODULE,
                .cra_init               = omap_sham_cra_md5_init,
                .cra_exit               = omap_sham_cra_exit,