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 @@ -29,9 +29,11 @@
  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 +#include "mtdsplit/mtdsplit.h"
  47
  48  /* Our partition linked list */
  49  static LIST_HEAD(mtd_partitions);
  50 @@ -45,13 +47,14 @@ struct mtd_part {
  51         struct list_head list;
  52  };
  53
  54 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
  55 +
  56  /*
  57   * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  58   * the pointer to that structure with this macro.
  59   */
  60  #define PART(x)  ((struct mtd_part *)(x))
  61
  62 -
  63  /*
  64   * MTD methods which simply translate the effective address and pass through
  65   * to the _real_ device.
  66 @@ -533,8 +536,10 @@ out_register:
  67         return slave;
  68  }
  69
  70 -int mtd_add_partition(struct mtd_info *master, char *name,
  71 -                     long long offset, long long length)
  72 +
  73 +static int
  74 +__mtd_add_partition(struct mtd_info *master, char *name,
  75 +                   long long offset, long long length, bool dup_check)
  76  {
  77         struct mtd_partition part;
  78         struct mtd_part *p, *new;
  79 @@ -566,21 +571,24 @@ int mtd_add_partition(struct mtd_info *m
  80         end = offset + length;
  81
  82         mutex_lock(&mtd_partitions_mutex);
  83 -       list_for_each_entry(p, &mtd_partitions, list)
  84 -               if (p->master == master) {
  85 -                       if ((start >= p->offset) &&
  86 -                           (start < (p->offset + p->mtd.size)))
  87 -                               goto err_inv;
  88 -
  89 -                       if ((end >= p->offset) &&
  90 -                           (end < (p->offset + p->mtd.size)))
  91 -                               goto err_inv;
  92 -               }
  93 +       if (dup_check) {
  94 +               list_for_each_entry(p, &mtd_partitions, list)
  95 +                       if (p->master == master) {
  96 +                               if ((start >= p->offset) &&
  97 +                                   (start < (p->offset + p->mtd.size)))
  98 +                                       goto err_inv;
  99 +
 100 +                               if ((end >= p->offset) &&
 101 +                                   (end < (p->offset + p->mtd.size)))
 102 +                                       goto err_inv;
 103 +                       }
 104 +       }
 105
 106         list_add(&new->list, &mtd_partitions);
 107         mutex_unlock(&mtd_partitions_mutex);
 108
 109         add_mtd_device(&new->mtd);
 110 +       mtd_partition_split(master, new);
 111
 112         return ret;
 113  err_inv:
 114 @@ -590,6 +598,12 @@ err_inv:
 115  }
 116  EXPORT_SYMBOL_GPL(mtd_add_partition);
 117
 118 +int mtd_add_partition(struct mtd_info *master, char *name,
 119 +                     long long offset, long long length)
 120 +{
 121 +       return __mtd_add_partition(master, name, offset, length, true);
 122 +}
 123 +
 124  int mtd_del_partition(struct mtd_info *master, int partno)
 125  {
 126         struct mtd_part *slave, *next;
 127 @@ -613,6 +627,144 @@ int mtd_del_partition(struct mtd_info *m
 128  }
 129  EXPORT_SYMBOL_GPL(mtd_del_partition);
 130
 131 +static inline unsigned long
 132 +mtd_pad_erasesize(struct mtd_info *mtd, int offset, int len)
 133 +{
 134 +       unsigned long mask = mtd->erasesize - 1;
 135 +
 136 +       len += offset & mask;
 137 +       len = (len + mask) & ~mask;
 138 +       len -= offset & mask;
 139 +       return len;
 140 +}
 141 +
 142 +#define ROOTFS_SPLIT_NAME "rootfs_data"
 143 +
 144 +struct squashfs_super_block {
 145 +       __le32 s_magic;
 146 +       __le32 pad0[9];
 147 +       __le64 bytes_used;
 148 +};
 149 +
 150 +
 151 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
 152 +{
 153 +       struct squashfs_super_block sb;
 154 +       int len, ret;
 155 +
 156 +       ret = mtd_read(master, offset, sizeof(sb), &len, (void *) &sb);
 157 +       if (ret || (len != sizeof(sb))) {
 158 +               printk(KERN_ALERT "split_squashfs: error occured while reading "
 159 +                       "from \"%s\"\n", master->name);
 160 +               return -EINVAL;
 161 +       }
 162 +
 163 +       if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
 164 +               printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
 165 +                       master->name);
 166 +               *split_offset = 0;
 167 +               return 0;
 168 +       }
 169 +
 170 +       if (le64_to_cpu((sb.bytes_used)) <= 0) {
 171 +               printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
 172 +                       master->name);
 173 +               *split_offset = 0;
 174 +               return 0;
 175 +       }
 176 +
 177 +       len = (u32) le64_to_cpu(sb.bytes_used);
 178 +       len = mtd_pad_erasesize(master, offset, len);
 179 +       *split_offset = offset + len;
 180 +
 181 +       return 0;
 182 +}
 183 +
 184 +static void split_rootfs_data(struct mtd_info *master, struct mtd_part *part)
 185 +{
 186 +       unsigned int split_offset = 0;
 187 +       unsigned int split_size;
 188 +       int ret;
 189 +
 190 +       ret = split_squashfs(master, part->offset, &split_offset);
 191 +       if (ret)
 192 +               return;
 193 +
 194 +       if (split_offset <= 0)
 195 +               return;
 196 +
 197 +       split_size = part->mtd.size - (split_offset - part->offset);
 198 +       printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=0x%x, len=0x%x\n",
 199 +               ROOTFS_SPLIT_NAME, split_offset, split_size);
 200 +
 201 +       __mtd_add_partition(master, ROOTFS_SPLIT_NAME, split_offset,
 202 +                           split_size, false);
 203 +}
 204 +
 205 +#define UBOOT_MAGIC    0x27051956
 206 +
 207 +static void split_uimage(struct mtd_info *master, struct mtd_part *part)
 208 +{
 209 +       struct {
 210 +               __be32 magic;
 211 +               __be32 pad[2];
 212 +               __be32 size;
 213 +       } hdr;
 214 +       size_t len;
 215 +
 216 +       if (mtd_read(master, part->offset, sizeof(hdr), &len, (void *) &hdr))
 217 +               return;
 218 +
 219 +       if (len != sizeof(hdr) || hdr.magic != cpu_to_be32(UBOOT_MAGIC))
 220 +               return;
 221 +
 222 +       len = be32_to_cpu(hdr.size) + 0x40;
 223 +       len = mtd_pad_erasesize(master, part->offset, len);
 224 +       if (len + master->erasesize > part->mtd.size)
 225 +               return;
 226 +
 227 +       __mtd_add_partition(master, "rootfs", part->offset + len,
 228 +                           part->mtd.size - len, false);
 229 +}
 230 +
 231 +#ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
 232 +#define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
 233 +#else
 234 +#define SPLIT_FIRMWARE_NAME    "unused"
 235 +#endif
 236 +
 237 +static void split_firmware(struct mtd_info *master, struct mtd_part *part)
 238 +{
 239 +       if (config_enabled(CONFIG_MTD_UIMAGE_SPLIT))
 240 +               split_uimage(master, part);
 241 +}
 242 +
 243 +void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
 244 +                                int offset, int size)
 245 +{
 246 +}
 247 +
 248 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
 249 +{
 250 +       static int rootfs_found = 0;
 251 +
 252 +       if (rootfs_found)
 253 +               return;
 254 +
 255 +       if (!strcmp(part->mtd.name, "rootfs")) {
 256 +               rootfs_found = 1;
 257 +
 258 +               if (config_enabled(CONFIG_MTD_ROOTFS_SPLIT))
 259 +                       split_rootfs_data(master, part);
 260 +       }
 261 +
 262 +       if (!strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
 263 +           config_enabled(CONFIG_MTD_SPLIT_FIRMWARE))
 264 +               split_firmware(master, part);
 265 +
 266 +       arch_split_mtd_part(master, part->mtd.name, part->offset,
 267 +                           part->mtd.size);
 268 +}
 269  /*
 270   * This function, given a master MTD object and a partition table, creates
 271   * and registers slave MTD objects which are bound to the master according to
 272 @@ -642,6 +794,7 @@ int add_mtd_partitions(struct mtd_info *
 273                 mutex_unlock(&mtd_partitions_mutex);
 274
 275                 add_mtd_device(&slave->mtd);
 276 +               mtd_partition_split(master, slave);
 277
 278                 cur_offset = slave->offset + slave->mtd.size;
 279         }
 280 --- a/include/linux/mtd/partitions.h
 281 +++ b/include/linux/mtd/partitions.h
 282 @@ -84,5 +84,7 @@ int mtd_add_partition(struct mtd_info *m
 283                       long long offset, long long length);
 284  int mtd_del_partition(struct mtd_info *master, int partno);
 285  uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 286 +extern void __weak arch_split_mtd_part(struct mtd_info *master,
 287 +                                      const char *name, int offset, int size);
 288
 289  #endif