target/linux/generic/patches-3.10/400-mtd-add-rootfs-split-support.patch

   1 --- a/drivers/mtd/Kconfig
   2 +++ b/drivers/mtd/Kconfig
   3 @@ -12,6 +12,32 @@ menuconfig MTD
   4
   5  if MTD
   6
   7 +menu "OpenWrt specific MTD options"
   8 +
   9 +config MTD_ROOTFS_ROOT_DEV
  10 +       bool "Automatically set 'rootfs' partition to be root filesystem"
  11 +       default y
  12 +
  13 +config MTD_ROOTFS_SPLIT
  14 +       bool "Automatically split 'rootfs' partition for squashfs"
  15 +       default y
  16 +
  17 +config MTD_SPLIT_FIRMWARE
  18 +       bool "Automatically split firmware partition for kernel+rootfs"
  19 +       default y
  20 +
  21 +config MTD_SPLIT_FIRMWARE_NAME
  22 +       string "Firmware partition name"
  23 +       depends on MTD_SPLIT_FIRMWARE
  24 +       default "firmware"
  25 +
  26 +config MTD_UIMAGE_SPLIT
  27 +       bool "Enable split support for firmware partitions containing a uImage"
  28 +       depends on MTD_SPLIT_FIRMWARE
  29 +       default y
  30 +
  31 +endmenu
  32 +
  33  config MTD_TESTS
  34         tristate "MTD tests support (DANGEROUS)"
  35         depends on m
  36 --- a/drivers/mtd/mtdpart.c
  37 +++ b/drivers/mtd/mtdpart.c
  38 @@ -29,6 +29,7 @@
  39  #include <linux/kmod.h>
  40  #include <linux/mtd/mtd.h>
  41  #include <linux/mtd/partitions.h>
  42 +#include <linux/magic.h>
  43  #include <linux/err.h>
  44
  45  #include "mtdcore.h"
  46 @@ -45,13 +46,14 @@ struct mtd_part {
  47         struct list_head list;
  48  };
  49
  50 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
  51 +
  52  /*
  53   * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  54   * the pointer to that structure with this macro.
  55   */
  56  #define PART(x)  ((struct mtd_part *)(x))
  57
  58 -
  59  /*
  60   * MTD methods which simply translate the effective address and pass through
  61   * to the _real_ device.
  62 @@ -533,8 +535,10 @@ out_register:
  63         return slave;
  64  }
  65
  66 -int mtd_add_partition(struct mtd_info *master, char *name,
  67 -                     long long offset, long long length)
  68 +
  69 +static int
  70 +__mtd_add_partition(struct mtd_info *master, char *name,
  71 +                   long long offset, long long length, bool dup_check)
  72  {
  73         struct mtd_partition part;
  74         struct mtd_part *p, *new;
  75 @@ -566,21 +570,24 @@ int mtd_add_partition(struct mtd_info *m
  76         end = offset + length;
  77
  78         mutex_lock(&mtd_partitions_mutex);
  79 -       list_for_each_entry(p, &mtd_partitions, list)
  80 -               if (p->master == master) {
  81 -                       if ((start >= p->offset) &&
  82 -                           (start < (p->offset + p->mtd.size)))
  83 -                               goto err_inv;
  84 -
  85 -                       if ((end >= p->offset) &&
  86 -                           (end < (p->offset + p->mtd.size)))
  87 -                               goto err_inv;
  88 -               }
  89 +       if (dup_check) {
  90 +               list_for_each_entry(p, &mtd_partitions, list)
  91 +                       if (p->master == master) {
  92 +                               if ((start >= p->offset) &&
  93 +                                   (start < (p->offset + p->mtd.size)))
  94 +                                       goto err_inv;
  95 +
  96 +                               if ((end >= p->offset) &&
  97 +                                   (end < (p->offset + p->mtd.size)))
  98 +                                       goto err_inv;
  99 +                       }
 100 +       }
 101
 102         list_add(&new->list, &mtd_partitions);
 103         mutex_unlock(&mtd_partitions_mutex);
 104
 105         add_mtd_device(&new->mtd);
 106 +       mtd_partition_split(master, new);
 107
 108         return ret;
 109  err_inv:
 110 @@ -590,6 +597,12 @@ err_inv:
 111  }
 112  EXPORT_SYMBOL_GPL(mtd_add_partition);
 113
 114 +int mtd_add_partition(struct mtd_info *master, char *name,
 115 +                     long long offset, long long length)
 116 +{
 117 +       return __mtd_add_partition(master, name, offset, length, true);
 118 +}
 119 +
 120  int mtd_del_partition(struct mtd_info *master, int partno)
 121  {
 122         struct mtd_part *slave, *next;
 123 @@ -613,6 +626,144 @@ int mtd_del_partition(struct mtd_info *m
 124  }
 125  EXPORT_SYMBOL_GPL(mtd_del_partition);
 126
 127 +static inline unsigned long
 128 +mtd_pad_erasesize(struct mtd_info *mtd, int offset, int len)
 129 +{
 130 +       unsigned long mask = mtd->erasesize - 1;
 131 +
 132 +       len += offset & mask;
 133 +       len = (len + mask) & ~mask;
 134 +       len -= offset & mask;
 135 +       return len;
 136 +}
 137 +
 138 +#define ROOTFS_SPLIT_NAME "rootfs_data"
 139 +
 140 +struct squashfs_super_block {
 141 +       __le32 s_magic;
 142 +       __le32 pad0[9];
 143 +       __le64 bytes_used;
 144 +};
 145 +
 146 +
 147 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
 148 +{
 149 +       struct squashfs_super_block sb;
 150 +       int len, ret;
 151 +
 152 +       ret = mtd_read(master, offset, sizeof(sb), &len, (void *) &sb);
 153 +       if (ret || (len != sizeof(sb))) {
 154 +               printk(KERN_ALERT "split_squashfs: error occured while reading "
 155 +                       "from \"%s\"\n", master->name);
 156 +               return -EINVAL;
 157 +       }
 158 +
 159 +       if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
 160 +               printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
 161 +                       master->name);
 162 +               *split_offset = 0;
 163 +               return 0;
 164 +       }
 165 +
 166 +       if (le64_to_cpu((sb.bytes_used)) <= 0) {
 167 +               printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
 168 +                       master->name);
 169 +               *split_offset = 0;
 170 +               return 0;
 171 +       }
 172 +
 173 +       len = (u32) le64_to_cpu(sb.bytes_used);
 174 +       len = mtd_pad_erasesize(master, offset, len);
 175 +       *split_offset = offset + len;
 176 +
 177 +       return 0;
 178 +}
 179 +
 180 +static void split_rootfs_data(struct mtd_info *master, struct mtd_part *part)
 181 +{
 182 +       unsigned int split_offset = 0;
 183 +       unsigned int split_size;
 184 +       int ret;
 185 +
 186 +       ret = split_squashfs(master, part->offset, &split_offset);
 187 +       if (ret)
 188 +               return;
 189 +
 190 +       if (split_offset <= 0)
 191 +               return;
 192 +
 193 +       split_size = part->mtd.size - (split_offset - part->offset);
 194 +       printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=0x%x, len=0x%x\n",
 195 +               ROOTFS_SPLIT_NAME, split_offset, split_size);
 196 +
 197 +       __mtd_add_partition(master, ROOTFS_SPLIT_NAME, split_offset,
 198 +                           split_size, false);
 199 +}
 200 +
 201 +#define UBOOT_MAGIC    0x27051956
 202 +
 203 +static void split_uimage(struct mtd_info *master, struct mtd_part *part)
 204 +{
 205 +       struct {
 206 +               __be32 magic;
 207 +               __be32 pad[2];
 208 +               __be32 size;
 209 +       } hdr;
 210 +       size_t len;
 211 +
 212 +       if (mtd_read(master, part->offset, sizeof(hdr), &len, (void *) &hdr))
 213 +               return;
 214 +
 215 +       if (len != sizeof(hdr) || hdr.magic != cpu_to_be32(UBOOT_MAGIC))
 216 +               return;
 217 +
 218 +       len = be32_to_cpu(hdr.size) + 0x40;
 219 +       len = mtd_pad_erasesize(master, part->offset, len);
 220 +       if (len + master->erasesize > part->mtd.size)
 221 +               return;
 222 +
 223 +       __mtd_add_partition(master, "rootfs", part->offset + len,
 224 +                           part->mtd.size - len, false);
 225 +}
 226 +
 227 +#ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
 228 +#define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
 229 +#else
 230 +#define SPLIT_FIRMWARE_NAME    "unused"
 231 +#endif
 232 +
 233 +static void split_firmware(struct mtd_info *master, struct mtd_part *part)
 234 +{
 235 +       if (config_enabled(CONFIG_MTD_UIMAGE_SPLIT))
 236 +               split_uimage(master, part);
 237 +}
 238 +
 239 +void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
 240 +                                int offset, int size)
 241 +{
 242 +}
 243 +
 244 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
 245 +{
 246 +       static int rootfs_found = 0;
 247 +
 248 +       if (rootfs_found)
 249 +               return;
 250 +
 251 +       if (!strcmp(part->mtd.name, "rootfs")) {
 252 +               rootfs_found = 1;
 253 +
 254 +               if (config_enabled(CONFIG_MTD_ROOTFS_SPLIT))
 255 +                       split_rootfs_data(master, part);
 256 +       }
 257 +
 258 +       if (!strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
 259 +           config_enabled(CONFIG_MTD_SPLIT_FIRMWARE))
 260 +               split_firmware(master, part);
 261 +
 262 +       arch_split_mtd_part(master, part->mtd.name, part->offset,
 263 +                           part->mtd.size);
 264 +}
 265  /*
 266   * This function, given a master MTD object and a partition table, creates
 267   * and registers slave MTD objects which are bound to the master according to
 268 @@ -642,6 +793,7 @@ int add_mtd_partitions(struct mtd_info *
 269                 mutex_unlock(&mtd_partitions_mutex);
 270
 271                 add_mtd_device(&slave->mtd);
 272 +               mtd_partition_split(master, slave);
 273
 274                 cur_offset = slave->offset + slave->mtd.size;
 275         }
 276 --- a/include/linux/mtd/partitions.h
 277 +++ b/include/linux/mtd/partitions.h
 278 @@ -84,5 +84,7 @@ int mtd_add_partition(struct mtd_info *m
 279                       long long offset, long long length);
 280  int mtd_del_partition(struct mtd_info *master, int partno);
 281  uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 282 +extern void __weak arch_split_mtd_part(struct mtd_info *master,
 283 +                                      const char *name, int offset, int size);
 284
 285  #endif