target/linux/generic/patches-3.2/400-rootfs_split.patch

   1 --- a/drivers/mtd/Kconfig
   2 +++ b/drivers/mtd/Kconfig
   3 @@ -23,6 +23,14 @@ config MTD_TESTS
   4           WARNING: some of the tests will ERASE entire MTD device which they
   5           test. Do not use these tests unless you really know what you do.
   6
   7 +config MTD_ROOTFS_ROOT_DEV
   8 +       bool "Automatically set 'rootfs' partition to be root filesystem"
   9 +       default y
  10 +
  11 +config MTD_ROOTFS_SPLIT
  12 +       bool "Automatically split 'rootfs' partition for squashfs"
  13 +       default y
  14 +
  15  config MTD_REDBOOT_PARTS
  16         tristate "RedBoot partition table parsing"
  17         ---help---
  18 --- a/drivers/mtd/mtdpart.c
  19 +++ b/drivers/mtd/mtdpart.c
  20 @@ -29,6 +29,8 @@
  21  #include <linux/kmod.h>
  22  #include <linux/mtd/mtd.h>
  23  #include <linux/mtd/partitions.h>
  24 +#include <linux/root_dev.h>
  25 +#include <linux/magic.h>
  26  #include <linux/err.h>
  27
  28  #include "mtdcore.h"
  29 @@ -50,7 +52,7 @@ struct mtd_part {
  30   * the pointer to that structure with this macro.
  31   */
  32  #define PART(x)  ((struct mtd_part *)(x))
  33 -
  34 +#define IS_PART(mtd) (mtd->read == part_read)
  35
  36  /*
  37   * MTD methods which simply translate the effective address and pass through
  38 @@ -650,6 +652,155 @@ int mtd_del_partition(struct mtd_info *m
  39  }
  40  EXPORT_SYMBOL_GPL(mtd_del_partition);
  41
  42 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
  43 +#define ROOTFS_SPLIT_NAME "rootfs_data"
  44 +#define ROOTFS_REMOVED_NAME "<removed>"
  45 +
  46 +struct squashfs_super_block {
  47 +       __le32 s_magic;
  48 +       __le32 pad0[9];
  49 +       __le64 bytes_used;
  50 +};
  51 +
  52 +
  53 +static int split_squashfs(struct mtd_info *master, int offset, int *split_offset)
  54 +{
  55 +       struct squashfs_super_block sb;
  56 +       int len, ret;
  57 +
  58 +       ret = master->read(master, offset, sizeof(sb), &len, (void *) &sb);
  59 +       if (ret || (len != sizeof(sb))) {
  60 +               printk(KERN_ALERT "split_squashfs: error occured while reading "
  61 +                       "from \"%s\"\n", master->name);
  62 +               return -EINVAL;
  63 +       }
  64 +
  65 +       if (SQUASHFS_MAGIC != le32_to_cpu(sb.s_magic) ) {
  66 +               printk(KERN_ALERT "split_squashfs: no squashfs found in \"%s\"\n",
  67 +                       master->name);
  68 +               *split_offset = 0;
  69 +               return 0;
  70 +       }
  71 +
  72 +       if (le64_to_cpu((sb.bytes_used)) <= 0) {
  73 +               printk(KERN_ALERT "split_squashfs: squashfs is empty in \"%s\"\n",
  74 +                       master->name);
  75 +               *split_offset = 0;
  76 +               return 0;
  77 +       }
  78 +
  79 +       len = (u32) le64_to_cpu(sb.bytes_used);
  80 +       len += (offset & 0x000fffff);
  81 +       len +=  (master->erasesize - 1);
  82 +       len &= ~(master->erasesize - 1);
  83 +       len -= (offset & 0x000fffff);
  84 +       *split_offset = offset + len;
  85 +
  86 +       return 0;
  87 +}
  88 +
  89 +static int split_rootfs_data(struct mtd_info *master, struct mtd_info *rpart, const struct mtd_partition *part)
  90 +{
  91 +       struct mtd_partition *dpart;
  92 +       struct mtd_part *slave = NULL;
  93 +       struct mtd_part *spart;
  94 +       int ret, split_offset = 0;
  95 +
  96 +       spart = PART(rpart);
  97 +       ret = split_squashfs(master, spart->offset, &split_offset);
  98 +       if (ret)
  99 +               return ret;
 100 +
 101 +       if (split_offset <= 0)
 102 +               return 0;
 103 +
 104 +       dpart = kmalloc(sizeof(*part)+sizeof(ROOTFS_SPLIT_NAME)+1, GFP_KERNEL);
 105 +       if (dpart == NULL) {
 106 +               printk(KERN_INFO "split_squashfs: no memory for partition \"%s\"\n",
 107 +                       ROOTFS_SPLIT_NAME);
 108 +               return -ENOMEM;
 109 +       }
 110 +
 111 +       memcpy(dpart, part, sizeof(*part));
 112 +       dpart->name = (unsigned char *)&dpart[1];
 113 +       strcpy(dpart->name, ROOTFS_SPLIT_NAME);
 114 +
 115 +       dpart->size = rpart->size - (split_offset - spart->offset);
 116 +       dpart->offset = split_offset;
 117 +
 118 +       if (dpart == NULL)
 119 +               return 1;
 120 +
 121 +       printk(KERN_INFO "mtd: partition \"%s\" created automatically, ofs=%llX, len=%llX \n",
 122 +               ROOTFS_SPLIT_NAME, dpart->offset, dpart->size);
 123 +
 124 +       slave = allocate_partition(master, dpart, 0, split_offset);
 125 +       if (IS_ERR(slave))
 126 +               return PTR_ERR(slave);
 127 +       mutex_lock(&mtd_partitions_mutex);
 128 +       list_add(&slave->list, &mtd_partitions);
 129 +       mutex_unlock(&mtd_partitions_mutex);
 130 +
 131 +       add_mtd_device(&slave->mtd);
 132 +
 133 +       rpart->split = &slave->mtd;
 134 +
 135 +       return 0;
 136 +}
 137 +
 138 +static int refresh_rootfs_split(struct mtd_info *mtd)
 139 +{
 140 +       struct mtd_partition tpart;
 141 +       struct mtd_part *part;
 142 +       char *name;
 143 +       //int index = 0;
 144 +       int offset, size;
 145 +       int ret;
 146 +
 147 +       part = PART(mtd);
 148 +
 149 +       /* check for the new squashfs offset first */
 150 +       ret = split_squashfs(part->master, part->offset, &offset);
 151 +       if (ret)
 152 +               return ret;
 153 +
 154 +       if ((offset > 0) && !mtd->split) {
 155 +               printk(KERN_INFO "%s: creating new split partition for \"%s\"\n", __func__, mtd->name);
 156 +               /* if we don't have a rootfs split partition, create a new one */
 157 +               tpart.name = (char *) mtd->name;
 158 +               tpart.size = mtd->size;
 159 +               tpart.offset = part->offset;
 160 +
 161 +               return split_rootfs_data(part->master, &part->mtd, &tpart);
 162 +       } else if ((offset > 0) && mtd->split) {
 163 +               /* update the offsets of the existing partition */
 164 +               size = mtd->size + part->offset - offset;
 165 +
 166 +               part = PART(mtd->split);
 167 +               part->offset = offset;
 168 +               part->mtd.size = size;
 169 +               printk(KERN_INFO "%s: %s partition \"" ROOTFS_SPLIT_NAME "\", offset: 0x%06x (0x%06x)\n",
 170 +                       __func__, (!strcmp(part->mtd.name, ROOTFS_SPLIT_NAME) ? "updating" : "creating"),
 171 +                       (u32) part->offset, (u32) part->mtd.size);
 172 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 173 +               strcpy(name, ROOTFS_SPLIT_NAME);
 174 +               part->mtd.name = name;
 175 +       } else if ((offset <= 0) && mtd->split) {
 176 +               printk(KERN_INFO "%s: removing partition \"%s\"\n", __func__, mtd->split->name);
 177 +
 178 +               /* mark existing partition as removed */
 179 +               part = PART(mtd->split);
 180 +               name = kmalloc(sizeof(ROOTFS_SPLIT_NAME) + 1, GFP_KERNEL);
 181 +               strcpy(name, ROOTFS_REMOVED_NAME);
 182 +               part->mtd.name = name;
 183 +               part->offset = 0;
 184 +               part->mtd.size = 0;
 185 +       }
 186 +
 187 +       return 0;
 188 +}
 189 +#endif /* CONFIG_MTD_ROOTFS_SPLIT */
 190 +
 191  /*
 192   * This function, given a master MTD object and a partition table, creates
 193   * and registers slave MTD objects which are bound to the master according to
 194 @@ -666,6 +817,9 @@ int add_mtd_partitions(struct mtd_info *
 195         struct mtd_part *slave;
 196         uint64_t cur_offset = 0;
 197         int i;
 198 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 199 +       int ret;
 200 +#endif
 201
 202         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 203
 204 @@ -680,12 +834,53 @@ int add_mtd_partitions(struct mtd_info *
 205
 206                 add_mtd_device(&slave->mtd);
 207
 208 +               if (!strcmp(parts[i].name, "rootfs")) {
 209 +#ifdef CONFIG_MTD_ROOTFS_ROOT_DEV
 210 +                       if (ROOT_DEV == 0) {
 211 +                               printk(KERN_NOTICE "mtd: partition \"rootfs\" "
 212 +                                       "set to be root filesystem\n");
 213 +                               ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, slave->mtd.index);
 214 +                       }
 215 +#endif
 216 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 217 +                       ret = split_rootfs_data(master, &slave->mtd, &parts[i]);
 218 +                       /* if (ret == 0)
 219 +                        *      j++; */
 220 +#endif
 221 +               }
 222 +
 223                 cur_offset = slave->offset + slave->mtd.size;
 224         }
 225
 226         return 0;
 227  }
 228
 229 +int mtd_device_refresh(struct mtd_info *mtd)
 230 +{
 231 +       int ret = 0;
 232 +
 233 +       if (IS_PART(mtd)) {
 234 +               struct mtd_part *part;
 235 +               struct mtd_info *master;
 236 +
 237 +               part = PART(mtd);
 238 +               master = part->master;
 239 +               if (master->refresh_device)
 240 +                       ret = master->refresh_device(master);
 241 +       }
 242 +
 243 +       if (!ret && mtd->refresh_device)
 244 +               ret = mtd->refresh_device(mtd);
 245 +
 246 +#ifdef CONFIG_MTD_ROOTFS_SPLIT
 247 +       if (!ret && IS_PART(mtd) && !strcmp(mtd->name, "rootfs"))
 248 +               refresh_rootfs_split(mtd);
 249 +#endif
 250 +
 251 +       return 0;
 252 +}
 253 +EXPORT_SYMBOL_GPL(mtd_device_refresh);
 254 +
 255  static DEFINE_SPINLOCK(part_parser_lock);
 256  static LIST_HEAD(part_parsers);
 257
 258 --- a/drivers/mtd/mtdchar.c
 259 +++ b/drivers/mtd/mtdchar.c
 260 @@ -1026,6 +1026,12 @@ static int mtd_ioctl(struct file *file,
 261                 break;
 262         }
 263
 264 +       case MTDREFRESH:
 265 +       {
 266 +               ret = mtd_device_refresh(mtd);
 267 +               break;
 268 +       }
 269 +
 270         default:
 271                 ret = -ENOTTY;
 272         }
 273 --- a/include/linux/mtd/mtd.h
 274 +++ b/include/linux/mtd/mtd.h
 275 @@ -114,6 +114,7 @@ struct nand_ecclayout {
 276
 277  struct module; /* only needed for owner field in mtd_info */
 278
 279 +struct mtd_info;
 280  struct mtd_info {
 281         u_char type;
 282         uint32_t flags;
 283 @@ -266,6 +267,9 @@ struct mtd_info {
 284         struct device dev;
 285         int usecount;
 286
 287 +       int (*refresh_device)(struct mtd_info *mtd);
 288 +       struct mtd_info *split;
 289 +
 290         /* If the driver is something smart, like UBI, it may need to maintain
 291          * its own reference counting. The below functions are only for driver.
 292          * The driver may register its callbacks. These callbacks are not
 293 @@ -321,6 +325,7 @@ extern int mtd_device_parse_register(str
 294                               int defnr_parts);
 295  #define mtd_device_register(master, parts, nr_parts)   \
 296         mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
 297 +extern int mtd_device_refresh(struct mtd_info *master);
 298  extern int mtd_device_unregister(struct mtd_info *master);
 299  extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
 300  extern int __get_mtd_device(struct mtd_info *mtd);
 301 --- a/include/linux/mtd/partitions.h
 302 +++ b/include/linux/mtd/partitions.h
 303 @@ -36,12 +36,14 @@
 304   * erasesize aligned (e.g. use MTDPART_OFS_NEXTBLK).
 305   */
 306
 307 +struct mtd_partition;
 308  struct mtd_partition {
 309         char *name;                     /* identifier string */
 310         uint64_t size;                  /* partition size */
 311         uint64_t offset;                /* offset within the master MTD space */
 312         uint32_t mask_flags;            /* master MTD flags to mask out for this partition */
 313         struct nand_ecclayout *ecclayout;       /* out of band layout for this partition (NAND only) */
 314 +       int (*refresh_partition)(struct mtd_info *);
 315  };
 316
 317  #define MTDPART_OFS_RETAIN     (-3)
 318 --- a/include/mtd/mtd-abi.h
 319 +++ b/include/mtd/mtd-abi.h
 320 @@ -201,6 +201,7 @@ struct otp_info {
 321   * modes (see "struct mtd_write_req")
 322   */
 323  #define MEMWRITE               _IOWR('M', 24, struct mtd_write_req)
 324 +#define MTDREFRESH             _IO('M', 50)
 325
 326  /*
 327   * Obsolete legacy interface. Keep it in order not to break userspace