target/linux/apm821xx/patches-4.14/020-0009-crypto-crypto4xx-refactor-crypto4xx_copy_pkt_to_dst.patch

   1 From 5c727f92ea5e019fd216f73009eee2b6e0867726 Mon Sep 17 00:00:00 2001
   2 From: Christian Lamparter <chunkeey@googlemail.com>
   3 Date: Fri, 25 Aug 2017 15:47:22 +0200
   4 Subject: [PATCH 09/25] crypto: crypto4xx - refactor
   5  crypto4xx_copy_pkt_to_dst()
   6
   7 This patch refactors the crypto4xx_copy_pkt_to_dst() to use
   8 scatterwalk_map_and_copy() to copy the processed data between
   9 the crypto engine's scatter ring buffer and the destination
  10 specified by the ablkcipher_request.
  11
  12 This also makes the crypto4xx_fill_one_page() function redundant.
  13
  14 Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
  15 Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
  16 ---
  17  drivers/crypto/amcc/crypto4xx_core.c | 126 +++++++++--------------------------
  18  1 file changed, 30 insertions(+), 96 deletions(-)
  19
  20 --- a/drivers/crypto/amcc/crypto4xx_core.c
  21 +++ b/drivers/crypto/amcc/crypto4xx_core.c
  22 @@ -38,6 +38,7 @@
  23  #include <crypto/aes.h>
  24  #include <crypto/ctr.h>
  25  #include <crypto/sha.h>
  26 +#include <crypto/scatterwalk.h>
  27  #include "crypto4xx_reg_def.h"
  28  #include "crypto4xx_core.h"
  29  #include "crypto4xx_sa.h"
  30 @@ -481,111 +482,44 @@ static inline struct ce_sd *crypto4xx_ge
  31         return  (struct ce_sd *)(dev->sdr + sizeof(struct ce_sd) * idx);
  32  }
  33
  34 -static u32 crypto4xx_fill_one_page(struct crypto4xx_device *dev,
  35 -                                  dma_addr_t *addr, u32 *length,
  36 -                                  u32 *idx, u32 *offset, u32 *nbytes)
  37 -{
  38 -       u32 len;
  39 -
  40 -       if (*length > dev->scatter_buffer_size) {
  41 -               memcpy(phys_to_virt(*addr),
  42 -                       dev->scatter_buffer_va +
  43 -                       *idx * dev->scatter_buffer_size + *offset,
  44 -                       dev->scatter_buffer_size);
  45 -               *offset = 0;
  46 -               *length -= dev->scatter_buffer_size;
  47 -               *nbytes -= dev->scatter_buffer_size;
  48 -               if (*idx == PPC4XX_LAST_SD)
  49 -                       *idx = 0;
  50 -               else
  51 -                       (*idx)++;
  52 -               *addr = *addr +  dev->scatter_buffer_size;
  53 -               return 1;
  54 -       } else if (*length < dev->scatter_buffer_size) {
  55 -               memcpy(phys_to_virt(*addr),
  56 -                       dev->scatter_buffer_va +
  57 -                       *idx * dev->scatter_buffer_size + *offset, *length);
  58 -               if ((*offset + *length) == dev->scatter_buffer_size) {
  59 -                       if (*idx == PPC4XX_LAST_SD)
  60 -                               *idx = 0;
  61 -                       else
  62 -                               (*idx)++;
  63 -                       *nbytes -= *length;
  64 -                       *offset = 0;
  65 -               } else {
  66 -                       *nbytes -= *length;
  67 -                       *offset += *length;
  68 -               }
  69 -
  70 -               return 0;
  71 -       } else {
  72 -               len = (*nbytes <= dev->scatter_buffer_size) ?
  73 -                               (*nbytes) : dev->scatter_buffer_size;
  74 -               memcpy(phys_to_virt(*addr),
  75 -                       dev->scatter_buffer_va +
  76 -                       *idx * dev->scatter_buffer_size + *offset,
  77 -                       len);
  78 -               *offset = 0;
  79 -               *nbytes -= len;
  80 -
  81 -               if (*idx == PPC4XX_LAST_SD)
  82 -                       *idx = 0;
  83 -               else
  84 -                       (*idx)++;
  85 -
  86 -               return 0;
  87 -    }
  88 -}
  89 -
  90  static void crypto4xx_copy_pkt_to_dst(struct crypto4xx_device *dev,
  91                                       struct ce_pd *pd,
  92                                       struct pd_uinfo *pd_uinfo,
  93                                       u32 nbytes,
  94                                       struct scatterlist *dst)
  95  {
  96 -       dma_addr_t addr;
  97 -       u32 this_sd;
  98 -       u32 offset;
  99 -       u32 len;
 100 -       u32 i;
 101 -       u32 sg_len;
 102 -       struct scatterlist *sg;
 103 -
 104 -       this_sd = pd_uinfo->first_sd;
 105 -       offset = 0;
 106 -       i = 0;
 107 +       unsigned int first_sd = pd_uinfo->first_sd;
 108 +       unsigned int last_sd;
 109 +       unsigned int overflow = 0;
 110 +       unsigned int to_copy;
 111 +       unsigned int dst_start = 0;
 112 +
 113 +       /*
 114 +        * Because the scatter buffers are all neatly organized in one
 115 +        * big continuous ringbuffer; scatterwalk_map_and_copy() can
 116 +        * be instructed to copy a range of buffers in one go.
 117 +        */
 118 +
 119 +       last_sd = (first_sd + pd_uinfo->num_sd);
 120 +       if (last_sd > PPC4XX_LAST_SD) {
 121 +               last_sd = PPC4XX_LAST_SD;
 122 +               overflow = last_sd % PPC4XX_NUM_SD;
 123 +       }
 124
 125         while (nbytes) {
 126 -               sg = &dst[i];
 127 -               sg_len = sg->length;
 128 -               addr = dma_map_page(dev->core_dev->device, sg_page(sg),
 129 -                               sg->offset, sg->length, DMA_TO_DEVICE);
 130 -
 131 -               if (offset == 0) {
 132 -                       len = (nbytes <= sg->length) ? nbytes : sg->length;
 133 -                       while (crypto4xx_fill_one_page(dev, &addr, &len,
 134 -                               &this_sd, &offset, &nbytes))
 135 -                               ;
 136 -                       if (!nbytes)
 137 -                               return;
 138 -                       i++;
 139 -               } else {
 140 -                       len = (nbytes <= (dev->scatter_buffer_size - offset)) ?
 141 -                               nbytes : (dev->scatter_buffer_size - offset);
 142 -                       len = (sg->length < len) ? sg->length : len;
 143 -                       while (crypto4xx_fill_one_page(dev, &addr, &len,
 144 -                                              &this_sd, &offset, &nbytes))
 145 -                               ;
 146 -                       if (!nbytes)
 147 -                               return;
 148 -                       sg_len -= len;
 149 -                       if (sg_len) {
 150 -                               addr += len;
 151 -                               while (crypto4xx_fill_one_page(dev, &addr,
 152 -                                       &sg_len, &this_sd, &offset, &nbytes))
 153 -                                       ;
 154 -                       }
 155 -                       i++;
 156 +               void *buf = dev->scatter_buffer_va +
 157 +                       first_sd * PPC4XX_SD_BUFFER_SIZE;
 158 +
 159 +               to_copy = min(nbytes, PPC4XX_SD_BUFFER_SIZE *
 160 +                                     (1 + last_sd - first_sd));
 161 +               scatterwalk_map_and_copy(buf, dst, dst_start, to_copy, 1);
 162 +               nbytes -= to_copy;
 163 +
 164 +               if (overflow) {
 165 +                       first_sd = 0;
 166 +                       last_sd = overflow;
 167 +                       dst_start += to_copy;
 168 +                       overflow = 0;
 169                 }
 170         }
 171  }