libfstools/mtd.c

   1 /*
   2  * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <sys/mount.h>
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17 #include <fcntl.h>
  18 #include <asm/byteorder.h>
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <mtd/mtd-user.h>
  23
  24 #include "libfstools.h"
  25
  26 #include "volume.h"
  27
  28 #define PATH_MAX                256
  29
  30 struct mtd_priv {
  31         int     fd;
  32         int     idx;
  33         char    *chr;
  34 };
  35
  36 static struct driver mtd_driver;
  37
  38 static int mtd_open(const char *mtd, int block)
  39 {
  40         FILE *fp;
  41         char dev[PATH_MAX];
  42         int i, ret, flags = O_RDWR | O_SYNC;
  43
  44         if ((fp = fopen("/proc/mtd", "r"))) {
  45                 while (fgets(dev, sizeof(dev), fp)) {
  46                         if (sscanf(dev, "mtd%d:", &i) && strstr(dev, mtd)) {
  47                                 snprintf(dev, sizeof(dev), "/dev/mtd%s/%d", (block ? "block" : ""), i);
  48                                 ret = open(dev, flags);
  49                                 if (ret < 0) {
  50                                         snprintf(dev, sizeof(dev), "/dev/mtd%s%d", (block ? "block" : ""), i);
  51                                         ret = open(dev, flags);
  52                                 }
  53                                 fclose(fp);
  54                                 return ret;
  55                         }
  56                 }
  57                 fclose(fp);
  58         }
  59
  60         return open(mtd, flags);
  61 }
  62
  63 static void mtd_volume_close(struct volume *v)
  64 {
  65         struct mtd_priv *p = (struct mtd_priv*) v->priv;
  66
  67         if (!p->fd)
  68                 return;
  69
  70         close(p->fd);
  71         p->fd = 0;
  72 }
  73
  74 static int mtd_volume_load(struct volume *v)
  75 {
  76         struct mtd_priv *p = (struct mtd_priv*) v->priv;
  77         struct mtd_info_user mtdInfo;
  78         struct erase_info_user mtdLockInfo;
  79
  80         if (p->fd)
  81                 return 0;
  82
  83         if (!p->chr)
  84                 return -1;
  85
  86         p->fd = mtd_open(p->chr, 0);
  87         if (p->fd < 0) {
  88                 p->fd = 0;
  89                 fprintf(stderr, "Could not open mtd device: %s\n", p->chr);
  90                 return -1;
  91         }
  92
  93         if (ioctl(p->fd, MEMGETINFO, &mtdInfo)) {
  94                 mtd_volume_close(v);
  95                 fprintf(stderr, "Could not get MTD device info from %s\n", p->chr);
  96                 return -1;
  97         }
  98
  99         v->size = mtdInfo.size;
 100         v->block_size = mtdInfo.erasesize;
 101         switch (mtdInfo.type) {
 102         case MTD_NORFLASH:
 103                 v->type = NORFLASH;
 104                 break;
 105         case MTD_NANDFLASH:
 106                 v->type = NANDFLASH;
 107                 break;
 108         case MTD_UBIVOLUME:
 109                 v->type = UBIVOLUME;
 110                 break;
 111         default:
 112                 v->type = UNKNOWN_TYPE;
 113                 break;
 114         }
 115
 116         mtdLockInfo.start = 0;
 117         mtdLockInfo.length = v->size;
 118         ioctl(p->fd, MEMUNLOCK, &mtdLockInfo);
 119
 120         return 0;
 121 }
 122
 123 static char* mtd_find_index(char *name)
 124 {
 125         FILE *fp = fopen("/proc/mtd", "r");
 126         static char line[256];
 127         char *index = NULL;
 128
 129         if(!fp)
 130                 return index;
 131
 132         while (!index && fgets(line, sizeof(line), fp)) {
 133                 char *ret;
 134
 135                 if ((ret = strstr(line, name)) && (ret[strlen(name)] == '"')) {
 136                         char *eol = strstr(line, ":");
 137
 138                         if (!eol)
 139                                 continue;
 140
 141                         *eol = '\0';
 142                         index = &line[3];
 143                 }
 144         }
 145
 146         fclose(fp);
 147
 148         return index;
 149 }
 150
 151 static int mtd_volume_find(struct volume *v, char *name)
 152 {
 153         char *idx = mtd_find_index(name);
 154         struct mtd_priv *p;
 155         char buffer[32];
 156
 157         if (!idx)
 158                 return -1;
 159
 160         p = calloc(1, sizeof(struct mtd_priv));
 161         if (!p)
 162                 return -1;
 163
 164         v->priv = p;
 165         v->name = strdup(name);
 166         v->drv = &mtd_driver;
 167         p->idx = atoi(idx);
 168
 169         snprintf(buffer, sizeof(buffer), "/dev/mtdblock%s", idx);
 170         v->blk = strdup(buffer);
 171
 172         snprintf(buffer, sizeof(buffer), "/dev/mtd%s", idx);
 173         p->chr = strdup(buffer);
 174
 175         if (mtd_volume_load(v)) {
 176                 fprintf(stderr, "reading %s failed\n", v->name);
 177                 return -1;
 178         }
 179
 180         return 0;
 181 }
 182
 183 static int mtd_volume_identify(struct volume *v)
 184 {
 185         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 186         __u32 deadc0de;
 187         __u16 jffs2;
 188         size_t sz;
 189
 190         if (mtd_volume_load(v)) {
 191                 fprintf(stderr, "reading %s failed\n", v->name);
 192                 return -1;
 193         }
 194
 195         sz = read(p->fd, &deadc0de, sizeof(deadc0de));
 196
 197         if (sz != sizeof(deadc0de)) {
 198                 fprintf(stderr, "reading %s failed: %s\n", v->name, strerror(errno));
 199                 return -1;
 200         }
 201
 202         if (deadc0de == __be32_to_cpu(0x4f575254))
 203                 return FS_SNAPSHOT;
 204
 205         deadc0de = __be32_to_cpu(deadc0de);
 206         if (deadc0de == 0xdeadc0de) {
 207                 fprintf(stderr, "jffs2 is not ready - marker found\n");
 208                 return FS_DEADCODE;
 209         }
 210
 211         jffs2 = __be16_to_cpu(deadc0de >> 16);
 212         if (jffs2 == 0x1985) {
 213                 fprintf(stderr, "jffs2 is ready\n");
 214                 return FS_JFFS2;
 215         }
 216
 217         if (v->type == UBIVOLUME && deadc0de == 0xffffffff) {
 218                 fprintf(stderr, "jffs2 is ready\n");
 219                 return FS_JFFS2;
 220         }
 221
 222         fprintf(stderr, "No jffs2 marker was found\n");
 223
 224         return FS_NONE;
 225 }
 226
 227 static int mtd_volume_erase(struct volume *v, int offset, int len)
 228 {
 229         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 230         struct erase_info_user eiu;
 231         int first_block, num_blocks;
 232
 233         if (mtd_volume_load(v))
 234                 return -1;
 235
 236         if (offset % v->block_size || len % v->block_size) {
 237                 fprintf(stderr, "mtd erase needs to be block aligned\n");
 238                 return -1;
 239         }
 240
 241         first_block = offset / v->block_size;
 242         num_blocks = len / v->block_size;
 243         eiu.length = v->block_size;
 244
 245         for (eiu.start = first_block * v->block_size;
 246                         eiu.start < v->size && eiu.start < (first_block + num_blocks) * v->block_size;
 247                         eiu.start += v->block_size) {
 248                 fprintf(stderr, "erasing %x %x\n", eiu.start, v->block_size);
 249                 ioctl(p->fd, MEMUNLOCK, &eiu);
 250                 if (ioctl(p->fd, MEMERASE, &eiu))
 251                         fprintf(stderr, "Failed to erase block at 0x%x\n", eiu.start);
 252         }
 253
 254         mtd_volume_close(v);
 255
 256         return 0;
 257 }
 258
 259 static int mtd_volume_erase_all(struct volume *v)
 260 {
 261         mtd_volume_erase(v, 0, v->size);
 262         mtd_volume_close(v);
 263
 264         return 0;
 265 }
 266
 267 static int mtd_volume_init(struct volume *v)
 268 {
 269         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 270         struct mtd_info_user mtdinfo;
 271         int ret;
 272
 273         if (mtd_volume_load(v))
 274                 return -1;
 275
 276         ret = ioctl(p->fd, MEMGETINFO, &mtdinfo);
 277         if (ret) {
 278                 fprintf(stderr, "ioctl(%d, MEMGETINFO) failed: %s\n", p->fd, strerror(errno));
 279         } else {
 280                 struct erase_info_user mtdlock;
 281
 282                 mtdlock.start = 0;
 283                 mtdlock.length = mtdinfo.size;
 284                 ioctl(p->fd, MEMUNLOCK, &mtdlock);
 285         }
 286
 287         return ret;
 288 }
 289
 290 static int mtd_volume_read(struct volume *v, void *buf, int offset, int length)
 291 {
 292         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 293
 294         if (mtd_volume_load(v))
 295                 return -1;
 296
 297         if (lseek(p->fd, offset, SEEK_SET) == (off_t) -1) {
 298                 fprintf(stderr, "lseek/read failed\n");
 299                 return -1;
 300         }
 301
 302         if (read(p->fd, buf, length) == -1) {
 303                 fprintf(stderr, "read failed\n");
 304                 return -1;
 305         }
 306
 307         return 0;
 308 }
 309
 310 static int mtd_volume_write(struct volume *v, void *buf, int offset, int length)
 311 {
 312         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 313
 314         if (mtd_volume_load(v))
 315                 return -1;
 316
 317         if (lseek(p->fd, offset, SEEK_SET) == (off_t) -1) {
 318                 fprintf(stderr, "lseek/write failed at offset %d\n", offset);
 319                 perror("lseek");
 320                 return -1;
 321         }
 322
 323         if (write(p->fd, buf, length) == -1) {
 324                 fprintf(stderr, "write failed\n");
 325                 return -1;
 326         }
 327
 328         return 0;
 329 }
 330
 331 static struct driver mtd_driver = {
 332         .name = "mtd",
 333         .find = mtd_volume_find,
 334         .init = mtd_volume_init,
 335         .erase = mtd_volume_erase,
 336         .erase_all = mtd_volume_erase_all,
 337         .read = mtd_volume_read,
 338         .write = mtd_volume_write,
 339         .identify = mtd_volume_identify,
 340 };
 341 DRIVER(mtd_driver);