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 "../fs-state.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                 if (strstr(line, name)) {
 134                         char *eol = strstr(line, ":");
 135
 136                         if (!eol)
 137                                 continue;
 138
 139                         *eol = '\0';
 140                         index = &line[3];
 141                 }
 142         }
 143
 144         fclose(fp);
 145
 146         return index;
 147 }
 148
 149 static int mtd_volume_find(struct volume *v, char *name)
 150 {
 151         char *idx = mtd_find_index(name);
 152         struct mtd_priv *p;
 153         char buffer[32];
 154
 155         if (!idx)
 156                 return -1;
 157
 158         p = calloc(1, sizeof(struct mtd_priv));
 159         if (!p)
 160                 return -1;
 161
 162         v->priv = p;
 163         v->name = strdup(name);
 164         v->drv = &mtd_driver;
 165         p->idx = atoi(idx);
 166
 167         snprintf(buffer, sizeof(buffer), "/dev/mtdblock%s", idx);
 168         v->blk = strdup(buffer);
 169
 170         snprintf(buffer, sizeof(buffer), "/dev/mtd%s", idx);
 171         p->chr = strdup(buffer);
 172
 173         return 0;
 174 }
 175
 176 static int mtd_volume_identify(struct volume *v)
 177 {
 178         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 179         __u32 deadc0de;
 180         __u16 jffs2;
 181         size_t sz;
 182
 183         if (mtd_volume_load(v)) {
 184                 fprintf(stderr, "reading %s failed\n", v->name);
 185                 return -1;
 186         }
 187
 188         sz = read(p->fd, &deadc0de, sizeof(deadc0de));
 189
 190         if (sz != sizeof(deadc0de)) {
 191                 fprintf(stderr, "reading %s failed: %s\n", v->name, strerror(errno));
 192                 return -1;
 193         }
 194
 195         if (deadc0de == 0x4f575254)
 196                 return FS_SNAPSHOT;
 197
 198         deadc0de = __be32_to_cpu(deadc0de);
 199         if (deadc0de == 0xdeadc0de) {
 200                 fprintf(stderr, "jffs2 is not ready - marker found\n");
 201                 return FS_DEADCODE;
 202         }
 203
 204         jffs2 = __be16_to_cpu(deadc0de >> 16);
 205         if (jffs2 == 0x1985) {
 206                 fprintf(stderr, "jffs2 is ready\n");
 207                 return FS_JFFS2;
 208         }
 209
 210         if (v->type == UBIVOLUME && deadc0de == 0xffffffff) {
 211                 fprintf(stderr, "jffs2 is ready\n");
 212                 return FS_JFFS2;
 213         }
 214
 215         fprintf(stderr, "No jffs2 marker was found\n");
 216
 217         return FS_NONE;
 218 }
 219
 220 static int mtd_volume_erase(struct volume *v, int offset, int len)
 221 {
 222         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 223         struct erase_info_user eiu;
 224         int first_block, num_blocks;
 225
 226         if (mtd_volume_load(v))
 227                 return -1;
 228
 229         if (offset % v->block_size || len % v->block_size) {
 230                 fprintf(stderr, "mtd erase needs to be block aligned\n");
 231                 return -1;
 232         }
 233
 234         first_block = offset / v->block_size;
 235         num_blocks = len / v->block_size;
 236         eiu.length = v->block_size;
 237
 238         for (eiu.start = first_block * v->block_size;
 239                         eiu.start < v->size && eiu.start < (first_block + num_blocks) * v->block_size;
 240                         eiu.start += v->block_size) {
 241                 fprintf(stderr, "erasing %x %x\n", eiu.start, v->block_size);
 242                 ioctl(p->fd, MEMUNLOCK, &eiu);
 243                 if (ioctl(p->fd, MEMERASE, &eiu))
 244                         fprintf(stderr, "Failed to erase block at 0x%x\n", eiu.start);
 245         }
 246
 247         mtd_volume_close(v);
 248
 249         return 0;
 250 }
 251
 252 static int mtd_volume_erase_all(struct volume *v)
 253 {
 254         mtd_volume_erase(v, 0, v->size);
 255         mtd_volume_close(v);
 256
 257         return 0;
 258 }
 259
 260 static int mtd_volume_init(struct volume *v)
 261 {
 262         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 263         struct mtd_info_user mtdinfo;
 264         int ret;
 265
 266         if (mtd_volume_load(v))
 267                 return -1;
 268
 269         ret = ioctl(p->fd, MEMGETINFO, &mtdinfo);
 270         if (ret) {
 271                 fprintf(stderr, "ioctl(%d, MEMGETINFO) failed: %s\n", p->fd, strerror(errno));
 272         } else {
 273                 struct erase_info_user mtdlock;
 274
 275                 mtdlock.start = 0;
 276                 mtdlock.length = mtdinfo.size;
 277                 ioctl(p->fd, MEMUNLOCK, &mtdlock);
 278         }
 279
 280         return ret;
 281 }
 282
 283 static int mtd_volume_read(struct volume *v, void *buf, int offset, int length)
 284 {
 285         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 286
 287         if (mtd_volume_load(v))
 288                 return -1;
 289
 290         if (lseek(p->fd, offset, SEEK_SET) == (off_t) -1) {
 291                 fprintf(stderr, "lseek/read failed\n");
 292                 return -1;
 293         }
 294
 295         if (read(p->fd, buf, length) == -1) {
 296                 fprintf(stderr, "read failed\n");
 297                 return -1;
 298         }
 299
 300         return 0;
 301 }
 302
 303 static int mtd_volume_write(struct volume *v, void *buf, int offset, int length)
 304 {
 305         struct mtd_priv *p = (struct mtd_priv*) v->priv;
 306
 307         if (mtd_volume_load(v))
 308                 return -1;
 309
 310         if (lseek(p->fd, offset, SEEK_SET) == (off_t) -1) {
 311                 fprintf(stderr, "lseek/write failed at offset %d\n", offset);
 312                 perror("lseek");
 313                 return -1;
 314         }
 315
 316         if (write(p->fd, buf, length) == -1) {
 317                 fprintf(stderr, "write failed\n");
 318                 return -1;
 319         }
 320
 321         return 0;
 322 }
 323
 324 static struct driver mtd_driver = {
 325         .name = "mtd",
 326         .find = mtd_volume_find,
 327         .init = mtd_volume_init,
 328         .erase = mtd_volume_erase,
 329         .erase_all = mtd_volume_erase_all,
 330         .read = mtd_volume_read,
 331         .write = mtd_volume_write,
 332         .identify = mtd_volume_identify,
 333 };
 334 DRIVER(mtd_driver);