target/linux/generic/patches-3.18/400-mtd-add-rootfs-split-support.patch

   1 --- a/drivers/mtd/Kconfig
   2 +++ b/drivers/mtd/Kconfig
   3 @@ -12,6 +12,28 @@ 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_SPLIT_FIRMWARE
  14 +       bool "Automatically split firmware partition for kernel+rootfs"
  15 +       default y
  16 +
  17 +config MTD_SPLIT_FIRMWARE_NAME
  18 +       string "Firmware partition name"
  19 +       depends on MTD_SPLIT_FIRMWARE
  20 +       default "firmware"
  21 +
  22 +config MTD_UIMAGE_SPLIT
  23 +       bool "Enable split support for firmware partitions containing a uImage"
  24 +       depends on MTD_SPLIT_FIRMWARE
  25 +       default y
  26 +
  27 +endmenu
  28 +
  29  config MTD_TESTS
  30         tristate "MTD tests support (DANGEROUS)"
  31         depends on m
  32 --- a/drivers/mtd/mtdpart.c
  33 +++ b/drivers/mtd/mtdpart.c
  34 @@ -29,9 +29,11 @@
  35  #include <linux/kmod.h>
  36  #include <linux/mtd/mtd.h>
  37  #include <linux/mtd/partitions.h>
  38 +#include <linux/magic.h>
  39  #include <linux/err.h>
  40
  41  #include "mtdcore.h"
  42 +#include "mtdsplit.h"
  43
  44  /* Our partition linked list */
  45  static LIST_HEAD(mtd_partitions);
  46 @@ -45,13 +47,14 @@ 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 @@ -547,8 +550,10 @@ out_register:
  63         return slave;
  64  }
  65
  66 -int mtd_add_partition(struct mtd_info *master, const char *name,
  67 -                     long long offset, long long length)
  68 +
  69 +static int
  70 +__mtd_add_partition(struct mtd_info *master, const 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 @@ -580,21 +585,24 @@ 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 @@ -604,6 +612,12 @@ err_inv:
 111  }
 112  EXPORT_SYMBOL_GPL(mtd_add_partition);
 113
 114 +int mtd_add_partition(struct mtd_info *master, const 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 @@ -627,6 +641,74 @@ 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 UBOOT_MAGIC    0x27051956
 139 +
 140 +static void split_uimage(struct mtd_info *master, struct mtd_part *part)
 141 +{
 142 +       struct {
 143 +               __be32 magic;
 144 +               __be32 pad[2];
 145 +               __be32 size;
 146 +       } hdr;
 147 +       size_t len;
 148 +
 149 +       if (mtd_read(master, part->offset, sizeof(hdr), &len, (void *) &hdr))
 150 +               return;
 151 +
 152 +       if (len != sizeof(hdr) || hdr.magic != cpu_to_be32(UBOOT_MAGIC))
 153 +               return;
 154 +
 155 +       len = be32_to_cpu(hdr.size) + 0x40;
 156 +       len = mtd_pad_erasesize(master, part->offset, len);
 157 +       if (len + master->erasesize > part->mtd.size)
 158 +               return;
 159 +
 160 +       __mtd_add_partition(master, "rootfs", part->offset + len,
 161 +                           part->mtd.size - len, false);
 162 +}
 163 +
 164 +#ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
 165 +#define SPLIT_FIRMWARE_NAME    CONFIG_MTD_SPLIT_FIRMWARE_NAME
 166 +#else
 167 +#define SPLIT_FIRMWARE_NAME    "unused"
 168 +#endif
 169 +
 170 +static void split_firmware(struct mtd_info *master, struct mtd_part *part)
 171 +{
 172 +       if (config_enabled(CONFIG_MTD_UIMAGE_SPLIT))
 173 +               split_uimage(master, part);
 174 +}
 175 +
 176 +void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
 177 +                                int offset, int size)
 178 +{
 179 +}
 180 +
 181 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
 182 +{
 183 +       static int rootfs_found = 0;
 184 +
 185 +       if (rootfs_found)
 186 +               return;
 187 +
 188 +       if (!strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
 189 +           config_enabled(CONFIG_MTD_SPLIT_FIRMWARE))
 190 +               split_firmware(master, part);
 191 +
 192 +       arch_split_mtd_part(master, part->mtd.name, part->offset,
 193 +                           part->mtd.size);
 194 +}
 195  /*
 196   * This function, given a master MTD object and a partition table, creates
 197   * and registers slave MTD objects which are bound to the master according to
 198 @@ -656,6 +738,7 @@ int add_mtd_partitions(struct mtd_info *
 199                 mutex_unlock(&mtd_partitions_mutex);
 200
 201                 add_mtd_device(&slave->mtd);
 202 +               mtd_partition_split(master, slave);
 203
 204                 cur_offset = slave->offset + slave->mtd.size;
 205         }
 206 --- a/include/linux/mtd/partitions.h
 207 +++ b/include/linux/mtd/partitions.h
 208 @@ -84,5 +84,7 @@ int mtd_add_partition(struct mtd_info *m
 209                       long long offset, long long length);
 210  int mtd_del_partition(struct mtd_info *master, int partno);
 211  uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 212 +extern void __weak arch_split_mtd_part(struct mtd_info *master,
 213 +                                      const char *name, int offset, int size);
 214
 215  #endif