root/drivers/crypto/omap-crypto.c

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DEFINITIONS

This source file includes following definitions.
  1. omap_crypto_copy_sg_lists
  2. omap_crypto_copy_sgs
  3. omap_crypto_check_sg
  4. omap_crypto_align_sg
  5. omap_crypto_cleanup

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * OMAP Crypto driver common support routines.
   4  *
   5  * Copyright (c) 2017 Texas Instruments Incorporated
   6  *   Tero Kristo <t-kristo@ti.com>
   7  */
   8 
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/scatterlist.h>
  12 #include <crypto/scatterwalk.h>
  13 
  14 #include "omap-crypto.h"
  15 
  16 static int omap_crypto_copy_sg_lists(int total, int bs,
  17                                      struct scatterlist **sg,
  18                                      struct scatterlist *new_sg, u16 flags)
  19 {
  20         int n = sg_nents(*sg);
  21         struct scatterlist *tmp;
  22 
  23         if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY)) {
  24                 new_sg = kmalloc_array(n, sizeof(*sg), GFP_KERNEL);
  25                 if (!new_sg)
  26                         return -ENOMEM;
  27 
  28                 sg_init_table(new_sg, n);
  29         }
  30 
  31         tmp = new_sg;
  32 
  33         while (*sg && total) {
  34                 int len = (*sg)->length;
  35 
  36                 if (total < len)
  37                         len = total;
  38 
  39                 if (len > 0) {
  40                         total -= len;
  41                         sg_set_page(tmp, sg_page(*sg), len, (*sg)->offset);
  42                         if (total <= 0)
  43                                 sg_mark_end(tmp);
  44                         tmp = sg_next(tmp);
  45                 }
  46 
  47                 *sg = sg_next(*sg);
  48         }
  49 
  50         *sg = new_sg;
  51 
  52         return 0;
  53 }
  54 
  55 static int omap_crypto_copy_sgs(int total, int bs, struct scatterlist **sg,
  56                                 struct scatterlist *new_sg, u16 flags)
  57 {
  58         void *buf;
  59         int pages;
  60         int new_len;
  61 
  62         new_len = ALIGN(total, bs);
  63         pages = get_order(new_len);
  64 
  65         buf = (void *)__get_free_pages(GFP_ATOMIC, pages);
  66         if (!buf) {
  67                 pr_err("%s: Couldn't allocate pages for unaligned cases.\n",
  68                        __func__);
  69                 return -ENOMEM;
  70         }
  71 
  72         if (flags & OMAP_CRYPTO_COPY_DATA) {
  73                 scatterwalk_map_and_copy(buf, *sg, 0, total, 0);
  74                 if (flags & OMAP_CRYPTO_ZERO_BUF)
  75                         memset(buf + total, 0, new_len - total);
  76         }
  77 
  78         if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY))
  79                 sg_init_table(new_sg, 1);
  80 
  81         sg_set_buf(new_sg, buf, new_len);
  82 
  83         *sg = new_sg;
  84 
  85         return 0;
  86 }
  87 
  88 static int omap_crypto_check_sg(struct scatterlist *sg, int total, int bs,
  89                                 u16 flags)
  90 {
  91         int len = 0;
  92         int num_sg = 0;
  93 
  94         if (!IS_ALIGNED(total, bs))
  95                 return OMAP_CRYPTO_NOT_ALIGNED;
  96 
  97         while (sg) {
  98                 num_sg++;
  99 
 100                 if (!IS_ALIGNED(sg->offset, 4))
 101                         return OMAP_CRYPTO_NOT_ALIGNED;
 102                 if (!IS_ALIGNED(sg->length, bs))
 103                         return OMAP_CRYPTO_NOT_ALIGNED;
 104 #ifdef CONFIG_ZONE_DMA
 105                 if (page_zonenum(sg_page(sg)) != ZONE_DMA)
 106                         return OMAP_CRYPTO_NOT_ALIGNED;
 107 #endif
 108 
 109                 len += sg->length;
 110                 sg = sg_next(sg);
 111 
 112                 if (len >= total)
 113                         break;
 114         }
 115 
 116         if ((flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY) && num_sg > 1)
 117                 return OMAP_CRYPTO_NOT_ALIGNED;
 118 
 119         if (len != total)
 120                 return OMAP_CRYPTO_BAD_DATA_LENGTH;
 121 
 122         return 0;
 123 }
 124 
 125 int omap_crypto_align_sg(struct scatterlist **sg, int total, int bs,
 126                          struct scatterlist *new_sg, u16 flags,
 127                          u8 flags_shift, unsigned long *dd_flags)
 128 {
 129         int ret;
 130 
 131         *dd_flags &= ~(OMAP_CRYPTO_COPY_MASK << flags_shift);
 132 
 133         if (flags & OMAP_CRYPTO_FORCE_COPY)
 134                 ret = OMAP_CRYPTO_NOT_ALIGNED;
 135         else
 136                 ret = omap_crypto_check_sg(*sg, total, bs, flags);
 137 
 138         if (ret == OMAP_CRYPTO_NOT_ALIGNED) {
 139                 ret = omap_crypto_copy_sgs(total, bs, sg, new_sg, flags);
 140                 if (ret)
 141                         return ret;
 142                 *dd_flags |= OMAP_CRYPTO_DATA_COPIED << flags_shift;
 143         } else if (ret == OMAP_CRYPTO_BAD_DATA_LENGTH) {
 144                 ret = omap_crypto_copy_sg_lists(total, bs, sg, new_sg, flags);
 145                 if (ret)
 146                         return ret;
 147                 if (!(flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY))
 148                         *dd_flags |= OMAP_CRYPTO_SG_COPIED << flags_shift;
 149         } else if (flags & OMAP_CRYPTO_FORCE_SINGLE_ENTRY) {
 150                 sg_set_buf(new_sg, sg_virt(*sg), (*sg)->length);
 151         }
 152 
 153         return 0;
 154 }
 155 EXPORT_SYMBOL_GPL(omap_crypto_align_sg);
 156 
 157 void omap_crypto_cleanup(struct scatterlist *sg, struct scatterlist *orig,
 158                          int offset, int len, u8 flags_shift,
 159                          unsigned long flags)
 160 {
 161         void *buf;
 162         int pages;
 163 
 164         flags >>= flags_shift;
 165         flags &= OMAP_CRYPTO_COPY_MASK;
 166 
 167         if (!flags)
 168                 return;
 169 
 170         buf = sg_virt(sg);
 171         pages = get_order(len);
 172 
 173         if (orig && (flags & OMAP_CRYPTO_COPY_MASK))
 174                 scatterwalk_map_and_copy(buf, orig, offset, len, 1);
 175 
 176         if (flags & OMAP_CRYPTO_DATA_COPIED)
 177                 free_pages((unsigned long)buf, pages);
 178         else if (flags & OMAP_CRYPTO_SG_COPIED)
 179                 kfree(sg);
 180 }
 181 EXPORT_SYMBOL_GPL(omap_crypto_cleanup);
 182 
 183 MODULE_DESCRIPTION("OMAP crypto support library.");
 184 MODULE_LICENSE("GPL v2");
 185 MODULE_AUTHOR("Tero Kristo <t-kristo@ti.com>");

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