debugfs/set_fields.c

   1 /*
   2  * set_fields.c --- set a superblock value
   3  *
   4  * Copyright (C) 2000, 2001, 2002, 2003, 2004 by Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #define _XOPEN_SOURCE 600 /* for inclusion of strptime() and strtoull */
  13
  14 #ifdef HAVE_STRTOULL
  15 #define STRTOULL strtoull
  16 #else
  17 #define STRTOULL strtoul
  18 #endif
  19
  20 #include "config.h"
  21 #include <stdio.h>
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24 #include <ctype.h>
  25 #include <string.h>
  26 #include <strings.h>
  27 #include <time.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #ifdef HAVE_ERRNO_H
  31 #include <errno.h>
  32 #endif
  33 #if HAVE_STRINGS_H
  34 #include <strings.h>
  35 #endif
  36 #include <fcntl.h>
  37 #include <utime.h>
  38
  39 #include "debugfs.h"
  40 #include "uuid/uuid.h"
  41 #include "e2p/e2p.h"
  42
  43 static struct ext2_super_block set_sb;
  44 static struct ext2_inode_large set_inode;
  45 static struct ext2_group_desc set_gd;
  46 static struct ext4_group_desc set_gd4;
  47 static struct mmp_struct set_mmp;
  48 static dgrp_t set_bg;
  49 static ext2_ino_t set_ino;
  50 static int array_idx;
  51
  52 #define FLAG_ARRAY      0x0001
  53
  54 struct field_set_info {
  55         const char      *name;
  56         void    *ptr;
  57         void    *ptr2;
  58         unsigned int    size;
  59         errcode_t (*func)(struct field_set_info *info, char *field, char *arg);
  60         int flags;
  61         int max_idx;
  62 };
  63
  64 static errcode_t parse_uint(struct field_set_info *info, char *field, char *arg);
  65 static errcode_t parse_int(struct field_set_info *info, char *field, char *arg);
  66 static errcode_t parse_string(struct field_set_info *info, char *field, char *arg);
  67 static errcode_t parse_uuid(struct field_set_info *info, char *field, char *arg);
  68 static errcode_t parse_hashalg(struct field_set_info *info, char *field, char *arg);
  69 static errcode_t parse_time(struct field_set_info *info, char *field, char *arg);
  70 static errcode_t parse_bmap(struct field_set_info *info, char *field, char *arg);
  71 static errcode_t parse_gd_csum(struct field_set_info *info, char *field, char *arg);
  72 static errcode_t parse_mmp_clear(struct field_set_info *info, char *field,
  73                                  char *arg);
  74
  75 static struct field_set_info super_fields[] = {
  76         { "inodes_count", &set_sb.s_inodes_count, NULL, 4, parse_uint },
  77         { "blocks_count", &set_sb.s_blocks_count, &set_sb.s_blocks_count_hi,
  78                 4, parse_uint },
  79         { "r_blocks_count", &set_sb.s_r_blocks_count,
  80                 &set_sb.s_r_blocks_count_hi, 4, parse_uint },
  81         { "free_blocks_count", &set_sb.s_free_blocks_count,
  82                 &set_sb.s_free_blocks_hi, 4, parse_uint },
  83         { "free_inodes_count", &set_sb.s_free_inodes_count, NULL, 4, parse_uint },
  84         { "first_data_block", &set_sb.s_first_data_block, NULL, 4, parse_uint },
  85         { "log_block_size", &set_sb.s_log_block_size, NULL, 4, parse_uint },
  86         { "log_cluster_size", &set_sb.s_log_cluster_size, NULL, 4, parse_int },
  87         { "blocks_per_group", &set_sb.s_blocks_per_group, NULL, 4, parse_uint },
  88         { "clusters_per_group", &set_sb.s_clusters_per_group, NULL, 4, parse_uint },
  89         { "inodes_per_group", &set_sb.s_inodes_per_group, NULL, 4, parse_uint },
  90         { "mtime", &set_sb.s_mtime, NULL, 4, parse_time },
  91         { "wtime", &set_sb.s_wtime, NULL, 4, parse_time },
  92         { "mnt_count", &set_sb.s_mnt_count, NULL, 2, parse_uint },
  93         { "max_mnt_count", &set_sb.s_max_mnt_count, NULL, 2, parse_int },
  94         /* s_magic */
  95         { "state", &set_sb.s_state, NULL, 2, parse_uint },
  96         { "errors", &set_sb.s_errors, NULL, 2, parse_uint },
  97         { "minor_rev_level", &set_sb.s_minor_rev_level, NULL, 2, parse_uint },
  98         { "lastcheck", &set_sb.s_lastcheck, NULL, 4, parse_time },
  99         { "checkinterval", &set_sb.s_checkinterval, NULL, 4, parse_uint },
 100         { "creator_os", &set_sb.s_creator_os, NULL, 4, parse_uint },
 101         { "rev_level", &set_sb.s_rev_level, NULL, 4, parse_uint },
 102         { "def_resuid", &set_sb.s_def_resuid, NULL, 2, parse_uint },
 103         { "def_resgid", &set_sb.s_def_resgid, NULL, 2, parse_uint },
 104         { "first_ino", &set_sb.s_first_ino, NULL, 4, parse_uint },
 105         { "inode_size", &set_sb.s_inode_size, NULL, 2, parse_uint },
 106         { "block_group_nr", &set_sb.s_block_group_nr, NULL, 2, parse_uint },
 107         { "feature_compat", &set_sb.s_feature_compat, NULL, 4, parse_uint },
 108         { "feature_incompat", &set_sb.s_feature_incompat, NULL, 4, parse_uint },
 109         { "feature_ro_compat", &set_sb.s_feature_ro_compat, NULL, 4, parse_uint },
 110         { "uuid", &set_sb.s_uuid, NULL, 16, parse_uuid },
 111         { "volume_name",  &set_sb.s_volume_name, NULL, 16, parse_string },
 112         { "last_mounted",  &set_sb.s_last_mounted, NULL, 64, parse_string },
 113         { "lastcheck",  &set_sb.s_lastcheck, NULL, 4, parse_uint },
 114         { "algorithm_usage_bitmap", &set_sb.s_algorithm_usage_bitmap, NULL,
 115                   4, parse_uint },
 116         { "prealloc_blocks", &set_sb.s_prealloc_blocks, NULL, 1, parse_uint },
 117         { "prealloc_dir_blocks", &set_sb.s_prealloc_dir_blocks, NULL, 1,
 118                   parse_uint },
 119         { "reserved_gdt_blocks", &set_sb.s_reserved_gdt_blocks, NULL, 2,
 120                   parse_uint },
 121         { "journal_uuid", &set_sb.s_journal_uuid, NULL, 16, parse_uuid },
 122         { "journal_inum", &set_sb.s_journal_inum, NULL, 4, parse_uint },
 123         { "journal_dev", &set_sb.s_journal_dev, NULL, 4, parse_uint },
 124         { "last_orphan", &set_sb.s_last_orphan, NULL, 4, parse_uint },
 125         { "hash_seed", &set_sb.s_hash_seed, NULL, 16, parse_uuid },
 126         { "def_hash_version", &set_sb.s_def_hash_version, NULL, 1, parse_hashalg },
 127         { "jnl_backup_type", &set_sb.s_jnl_backup_type, NULL, 1, parse_uint },
 128         { "desc_size", &set_sb.s_desc_size, NULL, 2, parse_uint },
 129         { "default_mount_opts", &set_sb.s_default_mount_opts, NULL, 4, parse_uint },
 130         { "first_meta_bg", &set_sb.s_first_meta_bg, NULL, 4, parse_uint },
 131         { "mkfs_time", &set_sb.s_mkfs_time, NULL, 4, parse_time },
 132         { "jnl_blocks", &set_sb.s_jnl_blocks[0], NULL, 4, parse_uint, FLAG_ARRAY,
 133           17 },
 134         { "min_extra_isize", &set_sb.s_min_extra_isize, NULL, 2, parse_uint },
 135         { "want_extra_isize", &set_sb.s_want_extra_isize, NULL, 2, parse_uint },
 136         { "flags", &set_sb.s_flags, NULL, 4, parse_uint },
 137         { "raid_stride", &set_sb.s_raid_stride, NULL, 2, parse_uint },
 138         { "min_extra_isize", &set_sb.s_min_extra_isize, NULL, 4, parse_uint },
 139         { "mmp_interval", &set_sb.s_mmp_update_interval, NULL, 2, parse_uint },
 140         { "mmp_block", &set_sb.s_mmp_block, NULL, 8, parse_uint },
 141         { "raid_stripe_width", &set_sb.s_raid_stripe_width, NULL, 4, parse_uint },
 142         { "log_groups_per_flex", &set_sb.s_log_groups_per_flex, NULL, 1, parse_uint },
 143         { "kbytes_written", &set_sb.s_kbytes_written, NULL, 8, parse_uint },
 144         { "snapshot_inum", &set_sb.s_snapshot_inum, NULL, 4, parse_uint },
 145         { "snapshot_id", &set_sb.s_snapshot_id, NULL, 4, parse_uint },
 146         { "snapshot_r_blocks_count", &set_sb.s_snapshot_r_blocks_count,
 147           NULL, 8, parse_uint },
 148         { "snapshot_list", &set_sb.s_snapshot_list, NULL, 4, parse_uint },
 149         { "mount_opts",  &set_sb.s_mount_opts, NULL, 64, parse_string },
 150         { "usr_quota_inum", &set_sb.s_usr_quota_inum, NULL, 4, parse_uint },
 151         { "grp_quota_inum", &set_sb.s_grp_quota_inum, NULL, 4, parse_uint },
 152         { "overhead_blocks", &set_sb.s_overhead_blocks, NULL, 4, parse_uint },
 153         { "backup_bgs", &set_sb.s_backup_bgs[0], NULL, 4, parse_uint,
 154           FLAG_ARRAY, 2 },
 155         { "checksum", &set_sb.s_checksum, NULL, 4, parse_uint },
 156         { "checksum_type", &set_sb.s_checksum_type, NULL, 1, parse_uint },
 157         { "error_count", &set_sb.s_error_count, NULL, 4, parse_uint },
 158         { "first_error_time", &set_sb.s_first_error_time, NULL, 4, parse_time },
 159         { "first_error_ino", &set_sb.s_first_error_ino, NULL, 4, parse_uint },
 160         { "first_error_block", &set_sb.s_first_error_block, NULL, 8, parse_uint },
 161         { "first_error_func", &set_sb.s_first_error_func, NULL, 32, parse_string },
 162         { "first_error_line", &set_sb.s_first_error_ino, NULL, 4, parse_uint },
 163         { "last_error_time", &set_sb.s_last_error_time, NULL, 4, parse_time },
 164         { "last_error_ino", &set_sb.s_last_error_ino, NULL, 4, parse_uint },
 165         { "last_error_block", &set_sb.s_last_error_block, NULL, 8, parse_uint },
 166         { "last_error_func", &set_sb.s_last_error_func, NULL, 32, parse_string },
 167         { "last_error_line", &set_sb.s_last_error_ino, NULL, 4, parse_uint },
 168         { 0, 0, 0, 0 }
 169 };
 170
 171 static struct field_set_info inode_fields[] = {
 172         { "inodes_count", &set_sb.s_inodes_count, NULL, 4, parse_uint },
 173         { "mode", &set_inode.i_mode, NULL, 2, parse_uint },
 174         { "uid", &set_inode.i_uid, &set_inode.osd2.linux2.l_i_uid_high,
 175                 2, parse_uint },
 176         { "size", &set_inode.i_size, &set_inode.i_size_high, 4, parse_uint },
 177         { "atime", &set_inode.i_atime, NULL, 4, parse_time },
 178         { "ctime", &set_inode.i_ctime, NULL, 4, parse_time },
 179         { "mtime", &set_inode.i_mtime, NULL, 4, parse_time },
 180         { "dtime", &set_inode.i_dtime, NULL, 4, parse_time },
 181         { "gid", &set_inode.i_gid, &set_inode.osd2.linux2.l_i_gid_high,
 182                 2, parse_uint },
 183         { "links_count", &set_inode.i_links_count, NULL, 2, parse_uint },
 184         /* Special case: i_blocks is 4 bytes, i_blocks_high is 2 bytes */
 185         { "blocks", &set_inode.i_blocks, &set_inode.osd2.linux2.l_i_blocks_hi,
 186                 6, parse_uint },
 187         { "flags", &set_inode.i_flags, NULL, 4, parse_uint },
 188         { "version", &set_inode.osd1.linux1.l_i_version,
 189                 &set_inode.i_version_hi, 4, parse_uint },
 190         { "translator", &set_inode.osd1.hurd1.h_i_translator, NULL, 4, parse_uint },
 191         { "block", &set_inode.i_block[0], NULL, 4, parse_uint, FLAG_ARRAY,
 192           EXT2_NDIR_BLOCKS },
 193         { "block[IND]", &set_inode.i_block[EXT2_IND_BLOCK], NULL, 4, parse_uint },
 194         { "block[DIND]", &set_inode.i_block[EXT2_DIND_BLOCK], NULL, 4, parse_uint },
 195         { "block[TIND]", &set_inode.i_block[EXT2_TIND_BLOCK], NULL, 4, parse_uint },
 196         { "generation", &set_inode.i_generation, NULL, 4, parse_uint },
 197         /* Special case: i_file_acl_high is 2 bytes */
 198         { "file_acl", &set_inode.i_file_acl,
 199                 &set_inode.osd2.linux2.l_i_file_acl_high, 6, parse_uint },
 200         { "dir_acl", &set_inode.i_dir_acl, NULL, 4, parse_uint },
 201         { "faddr", &set_inode.i_faddr, NULL, 4, parse_uint },
 202         { "frag", &set_inode.osd2.hurd2.h_i_frag, NULL, 1, parse_uint },
 203         { "fsize", &set_inode.osd2.hurd2.h_i_fsize, NULL, 1, parse_uint },
 204         { "checksum", &set_inode.osd2.linux2.l_i_checksum_lo,
 205                 &set_inode.i_checksum_hi, 2, parse_uint },
 206         { "author", &set_inode.osd2.hurd2.h_i_author, NULL,
 207                 4, parse_uint },
 208         { "extra_isize", &set_inode.i_extra_isize, NULL,
 209                 2, parse_uint },
 210         { "ctime_extra", &set_inode.i_ctime_extra, NULL,
 211                 4, parse_uint },
 212         { "mtime_extra", &set_inode.i_mtime_extra, NULL,
 213                 4, parse_uint },
 214         { "atime_extra", &set_inode.i_atime_extra, NULL,
 215                 4, parse_uint },
 216         { "crtime", &set_inode.i_crtime, NULL, 4, parse_uint },
 217         { "crtime_extra", &set_inode.i_crtime_extra, NULL,
 218                 4, parse_uint },
 219         { "bmap", NULL, NULL, 4, parse_bmap, FLAG_ARRAY },
 220         { 0, 0, 0, 0 }
 221 };
 222
 223 static struct field_set_info ext2_bg_fields[] = {
 224         { "block_bitmap", &set_gd.bg_block_bitmap, NULL, 4, parse_uint },
 225         { "inode_bitmap", &set_gd.bg_inode_bitmap, NULL, 4, parse_uint },
 226         { "inode_table", &set_gd.bg_inode_table, NULL, 4, parse_uint },
 227         { "free_blocks_count", &set_gd.bg_free_blocks_count, NULL, 2, parse_uint },
 228         { "free_inodes_count", &set_gd.bg_free_inodes_count, NULL, 2, parse_uint },
 229         { "used_dirs_count", &set_gd.bg_used_dirs_count, NULL, 2, parse_uint },
 230         { "flags", &set_gd.bg_flags, NULL, 2, parse_uint },
 231         { "itable_unused", &set_gd.bg_itable_unused, NULL, 2, parse_uint },
 232         { "checksum", &set_gd.bg_checksum, NULL, 2, parse_gd_csum },
 233         { 0, 0, 0, 0 }
 234 };
 235
 236 static struct field_set_info ext4_bg_fields[] = {
 237         { "block_bitmap", &set_gd4.bg_block_bitmap,
 238                 &set_gd4.bg_block_bitmap_hi, 4, parse_uint },
 239         { "inode_bitmap", &set_gd4.bg_inode_bitmap,
 240                 &set_gd4.bg_inode_bitmap_hi, 4, parse_uint },
 241         { "inode_table", &set_gd4.bg_inode_table,
 242                 &set_gd4.bg_inode_table_hi, 4, parse_uint },
 243         { "free_blocks_count", &set_gd4.bg_free_blocks_count,
 244                 &set_gd4.bg_free_blocks_count_hi, 2, parse_uint },
 245         { "free_inodes_count", &set_gd4.bg_free_inodes_count,
 246                 &set_gd4.bg_free_inodes_count_hi, 2, parse_uint },
 247         { "used_dirs_count", &set_gd4.bg_used_dirs_count,
 248                 &set_gd4.bg_used_dirs_count_hi, 2, parse_uint },
 249         { "flags", &set_gd4.bg_flags, NULL, 2, parse_uint },
 250         { "exclude_bitmap", &set_gd4.bg_exclude_bitmap_lo,
 251                 &set_gd4.bg_exclude_bitmap_hi, 4, parse_uint },
 252         { "block_bitmap_csum", &set_gd4.bg_block_bitmap_csum_lo,
 253                 &set_gd4.bg_block_bitmap_csum_hi, 2, parse_uint },
 254         { "inode_bitmap_csum", &set_gd4.bg_inode_bitmap_csum_lo,
 255                 &set_gd4.bg_inode_bitmap_csum_hi, 2, parse_uint },
 256         { "itable_unused", &set_gd4.bg_itable_unused,
 257                 &set_gd4.bg_itable_unused_hi, 2, parse_uint },
 258         { "checksum", &set_gd4.bg_checksum, NULL, 2, parse_gd_csum },
 259         { 0, 0, 0, 0 }
 260 };
 261
 262 static struct field_set_info mmp_fields[] = {
 263         { "clear", &set_mmp.mmp_magic, NULL, sizeof(set_mmp), parse_mmp_clear },
 264         { "magic", &set_mmp.mmp_magic, NULL, 4, parse_uint },
 265         { "seq", &set_mmp.mmp_seq, NULL, 4, parse_uint },
 266         { "time", &set_mmp.mmp_time, NULL, 8, parse_uint },
 267         { "nodename", &set_mmp.mmp_nodename, NULL, sizeof(set_mmp.mmp_nodename),
 268                 parse_string },
 269         { "bdevname", &set_mmp.mmp_bdevname, NULL, sizeof(set_mmp.mmp_bdevname),
 270                 parse_string },
 271         { "check_interval", &set_mmp.mmp_check_interval, NULL, 2, parse_uint },
 272         { "checksum", &set_mmp.mmp_checksum, NULL, 4, parse_uint },
 273 };
 274
 275 static int check_suffix(const char *field)
 276 {
 277         int len = strlen(field);
 278
 279         if (len <= 3)
 280                 return 0;
 281         field += len-3;
 282         if (!strcmp(field, "_lo"))
 283                 return 1;
 284         if (!strcmp(field, "_hi"))
 285                 return 2;
 286         return 0;
 287 }
 288
 289 static struct field_set_info *find_field(struct field_set_info *fields,
 290                                          char *field)
 291 {
 292         struct field_set_info *ss;
 293         const char      *prefix;
 294         char            *arg, *delim, *idx, *tmp;
 295         int             suffix, prefix_len;
 296
 297         if (fields == super_fields)
 298                 prefix = "s_";
 299         else if (fields == inode_fields)
 300                 prefix = "i_";
 301         else
 302                 prefix = "bg_";
 303         prefix_len = strlen(prefix);
 304         if (strncmp(field, prefix, prefix_len) == 0)
 305                 field += prefix_len;
 306
 307         arg = malloc(strlen(field)+1);
 308         if (!arg)
 309                 return NULL;
 310         strcpy(arg, field);
 311
 312         idx = strchr(arg, '[');
 313         if (idx) {
 314                 *idx++ = 0;
 315                 delim = idx + strlen(idx) - 1;
 316                 if (!*idx || *delim != ']')
 317                         idx = 0;
 318                 else
 319                         *delim = 0;
 320         }
 321         /*
 322          * Can we parse the number?
 323          */
 324         if (idx) {
 325                 array_idx = strtol(idx, &tmp, 0);
 326                 if (*tmp)
 327                         idx = 0;
 328         }
 329
 330         /*
 331          * If there is a valid _hi or a _lo suffix, strip it off
 332          */
 333         suffix = check_suffix(arg);
 334         if (suffix > 0)
 335                 arg[strlen(arg)-3] = 0;
 336
 337         for (ss = fields ; ss->name ; ss++) {
 338                 if (suffix && ss->ptr2 == 0)
 339                         continue;
 340                 if (ss->flags & FLAG_ARRAY) {
 341                         if (!idx || (strcmp(ss->name, arg) != 0))
 342                                 continue;
 343                         if (ss->max_idx > 0 && array_idx >= ss->max_idx)
 344                                 continue;
 345                 } else {
 346                         if (strcmp(ss->name, arg) != 0)
 347                                 continue;
 348                 }
 349                 free(arg);
 350                 return ss;
 351         }
 352         free(arg);
 353         return NULL;
 354 }
 355
 356 /*
 357  * Note: info->size == 6 is special; this means a base size 4 bytes,
 358  * and secondiory (high) size of 2 bytes.  This is needed for the
 359  * special case of i_blocks_high and i_file_acl_high.
 360  */
 361 static errcode_t parse_uint(struct field_set_info *info, char *field,
 362                             char *arg)
 363 {
 364         unsigned long long n, num, mask, limit;
 365         int suffix = check_suffix(field);
 366         char *tmp;
 367         void *field1 = info->ptr, *field2 = info->ptr2;
 368         int size = (info->size == 6) ? 4 : info->size;
 369         union {
 370                 __u64   *ptr64;
 371                 __u32   *ptr32;
 372                 __u16   *ptr16;
 373                 __u8    *ptr8;
 374         } u;
 375
 376         if (suffix == 1)
 377                 field2 = 0;
 378         if (suffix == 2) {
 379                 field1 = field2;
 380                 field2 = 0;
 381         }
 382
 383         u.ptr8 = (__u8 *) field1;
 384         if (info->flags & FLAG_ARRAY)
 385                 u.ptr8 += array_idx * info->size;
 386
 387         errno = 0;
 388         num = STRTOULL(arg, &tmp, 0);
 389         if (*tmp || errno) {
 390                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 391                         arg, info->name);
 392                 return EINVAL;
 393         }
 394         mask = ~0ULL >> ((8 - size) * 8);
 395         limit = ~0ULL >> ((8 - info->size) * 8);
 396         if (field2 && info->size != 6)
 397                 limit = ~0ULL >> ((8 - info->size*2) * 8);
 398
 399         if (num > limit) {
 400                 fprintf(stderr, "Value '%s' exceeds field %s maximum %llu.\n",
 401                         arg, info->name, limit);
 402                 return EINVAL;
 403         }
 404         n = num & mask;
 405         switch (size) {
 406         case 8:
 407                 /* Should never get here */
 408                 fprintf(stderr, "64-bit field %s has a second 64-bit field\n"
 409                         "defined; BUG?!?\n", info->name);
 410                 *u.ptr64 = 0;
 411                 break;
 412         case 4:
 413                 *u.ptr32 = n;
 414                 break;
 415         case 2:
 416                 *u.ptr16 = n;
 417                 break;
 418         case 1:
 419                 *u.ptr8 = n;
 420                 break;
 421         }
 422         if (!field2)
 423                 return 0;
 424         n = num >> (size*8);
 425         u.ptr8 = (__u8 *) field2;
 426         if (info->size == 6)
 427                 size = 2;
 428         switch (size) {
 429         case 8:
 430                 *u.ptr64 = n;
 431                 break;
 432         case 4:
 433                 *u.ptr32 = n;
 434                 break;
 435         case 2:
 436                 *u.ptr16 = n;
 437                 break;
 438         case 1:
 439                 *u.ptr8 = n;
 440                 break;
 441         }
 442         return 0;
 443 }
 444
 445 static errcode_t parse_int(struct field_set_info *info,
 446                            char *field EXT2FS_ATTR((unused)), char *arg)
 447 {
 448         long    num;
 449         char *tmp;
 450         __s32   *ptr32;
 451         __s16   *ptr16;
 452         __s8    *ptr8;
 453
 454         num = strtol(arg, &tmp, 0);
 455         if (*tmp) {
 456                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 457                         arg, info->name);
 458                 return EINVAL;
 459         }
 460         switch (info->size) {
 461         case 4:
 462                 ptr32 = (__s32 *) info->ptr;
 463                 *ptr32 = num;
 464                 break;
 465         case 2:
 466                 ptr16 = (__s16 *) info->ptr;
 467                 *ptr16 = num;
 468                 break;
 469         case 1:
 470                 ptr8 = (__s8 *) info->ptr;
 471                 *ptr8 = num;
 472                 break;
 473         }
 474         return 0;
 475 }
 476
 477 static errcode_t parse_string(struct field_set_info *info,
 478                               char *field EXT2FS_ATTR((unused)), char *arg)
 479 {
 480         char    *cp = (char *) info->ptr;
 481
 482         if (strlen(arg) >= info->size) {
 483                 fprintf(stderr, "Error maximum size for %s is %d.\n",
 484                         info->name, info->size);
 485                 return EINVAL;
 486         }
 487         strcpy(cp, arg);
 488         return 0;
 489 }
 490
 491 static errcode_t parse_time(struct field_set_info *info,
 492                             char *field EXT2FS_ATTR((unused)), char *arg)
 493 {
 494         time_t          t;
 495         __u32           *ptr32;
 496
 497         ptr32 = (__u32 *) info->ptr;
 498
 499         t = string_to_time(arg);
 500
 501         if (t == ((time_t) -1)) {
 502                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 503                         arg, info->name);
 504                 return EINVAL;
 505         }
 506         *ptr32 = t;
 507         return 0;
 508 }
 509
 510 static errcode_t parse_uuid(struct field_set_info *info,
 511                             char *field EXT2FS_ATTR((unused)), char *arg)
 512 {
 513         unsigned char * p = (unsigned char *) info->ptr;
 514
 515         if ((strcasecmp(arg, "null") == 0) ||
 516             (strcasecmp(arg, "clear") == 0)) {
 517                 uuid_clear(p);
 518         } else if (strcasecmp(arg, "time") == 0) {
 519                 uuid_generate_time(p);
 520         } else if (strcasecmp(arg, "random") == 0) {
 521                 uuid_generate(p);
 522         } else if (uuid_parse(arg, p)) {
 523                 fprintf(stderr, "Invalid UUID format: %s\n", arg);
 524                 return EINVAL;
 525         }
 526         return 0;
 527 }
 528
 529 static errcode_t parse_hashalg(struct field_set_info *info,
 530                                char *field EXT2FS_ATTR((unused)), char *arg)
 531 {
 532         int     hashv;
 533         unsigned char   *p = (unsigned char *) info->ptr;
 534
 535         hashv = e2p_string2hash(arg);
 536         if (hashv < 0) {
 537                 fprintf(stderr, "Invalid hash algorithm: %s\n", arg);
 538                 return EINVAL;
 539         }
 540         *p = hashv;
 541         return 0;
 542 }
 543
 544 static errcode_t parse_bmap(struct field_set_info *info,
 545                             char *field EXT2FS_ATTR((unused)), char *arg)
 546 {
 547         blk64_t         blk;
 548         errcode_t       retval;
 549         char            *tmp;
 550
 551         blk = strtoull(arg, &tmp, 0);
 552         if (*tmp) {
 553                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 554                         arg, info->name);
 555                 return EINVAL;
 556         }
 557
 558         retval = ext2fs_bmap2(current_fs, set_ino,
 559                               (struct ext2_inode *) &set_inode,
 560                               NULL, BMAP_ALLOC | BMAP_SET, array_idx, NULL,
 561                               &blk);
 562         if (retval) {
 563                 com_err("set_inode", retval, "while setting block map");
 564         }
 565         return retval;
 566 }
 567
 568 static errcode_t parse_gd_csum(struct field_set_info *info, char *field,
 569                                char *arg)
 570 {
 571
 572         if (strcmp(arg, "calc") == 0) {
 573                 ext2fs_group_desc_csum_set(current_fs, set_bg);
 574                 memcpy(&set_gd, ext2fs_group_desc(current_fs,
 575                                         current_fs->group_desc,
 576                                         set_bg),
 577                         sizeof(set_gd));
 578                 printf("Checksum set to 0x%04x\n",
 579                        ext2fs_bg_checksum(current_fs, set_bg));
 580                 return 0;
 581         }
 582
 583         return parse_uint(info, field, arg);
 584 }
 585
 586 static void print_possible_fields(struct field_set_info *fields)
 587 {
 588         struct field_set_info *ss;
 589         const char      *type, *cmd;
 590         FILE *f;
 591         char name[40], idx[40];
 592
 593         if (fields == super_fields) {
 594                 type = "Superblock";
 595                 cmd = "set_super_value";
 596         } else if (fields == inode_fields) {
 597                 type = "Inode";
 598                 cmd = "set_inode";
 599         } else if (fields == mmp_fields) {
 600                 type = "MMP";
 601                 cmd = "set_mmp_value";
 602         } else {
 603                 type = "Block group descriptor";
 604                 cmd = "set_block_group";
 605         }
 606         f = open_pager();
 607
 608         fprintf(f, "%s fields supported by the %s command:\n", type, cmd);
 609
 610         for (ss = fields ; ss->name ; ss++) {
 611                 type = "unknown";
 612                 if (ss->func == parse_string)
 613                         type = "string";
 614                 else if (ss->func == parse_int)
 615                         type = "integer";
 616                 else if (ss->func == parse_uint)
 617                         type = "unsigned integer";
 618                 else if (ss->func == parse_uuid)
 619                         type = "UUID";
 620                 else if (ss->func == parse_hashalg)
 621                         type = "hash algorithm";
 622                 else if (ss->func == parse_time)
 623                         type = "date/time";
 624                 else if (ss->func == parse_bmap)
 625                         type = "set physical->logical block map";
 626                 else if (ss->func == parse_gd_csum)
 627                         type = "unsigned integer OR \"calc\"";
 628                 strcpy(name, ss->name);
 629                 if (ss->flags & FLAG_ARRAY) {
 630                         if (ss->max_idx > 0)
 631                                 sprintf(idx, "[%d]", ss->max_idx);
 632                         else
 633                                 strcpy(idx, "[]");
 634                         strcat(name, idx);
 635                 }
 636                 if (ss->ptr2)
 637                         strcat(name, "[_hi|_lo]");
 638                 fprintf(f, "\t%-25s\t%s\n", name, type);
 639         }
 640         close_pager(f);
 641 }
 642
 643
 644 void do_set_super(int argc, char *argv[])
 645 {
 646         const char *usage = "<field> <value>\n"
 647                 "\t\"set_super_value -l\" will list the names of "
 648                 "superblock fields\n\twhich can be set.";
 649         static struct field_set_info *ss;
 650
 651         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 652                 print_possible_fields(super_fields);
 653                 return;
 654         }
 655
 656         if (common_args_process(argc, argv, 3, 3, "set_super_value",
 657                                 usage, CHECK_FS_RW))
 658                 return;
 659
 660         if ((ss = find_field(super_fields, argv[1])) == 0) {
 661                 com_err(argv[0], 0, "invalid field specifier: %s", argv[1]);
 662                 return;
 663         }
 664         set_sb = *current_fs->super;
 665         if (ss->func(ss, argv[1], argv[2]) == 0) {
 666                 *current_fs->super = set_sb;
 667                 ext2fs_mark_super_dirty(current_fs);
 668         }
 669 }
 670
 671 void do_set_inode(int argc, char *argv[])
 672 {
 673         const char *usage = "<inode> <field> <value>\n"
 674                 "\t\"set_inode_field -l\" will list the names of "
 675                 "the fields in an ext2 inode\n\twhich can be set.";
 676         static struct field_set_info *ss;
 677
 678         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 679                 print_possible_fields(inode_fields);
 680                 return;
 681         }
 682
 683         if (common_args_process(argc, argv, 4, 4, "set_inode",
 684                                 usage, CHECK_FS_RW))
 685                 return;
 686
 687         if ((ss = find_field(inode_fields, argv[2])) == 0) {
 688                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 689                 return;
 690         }
 691
 692         set_ino = string_to_inode(argv[1]);
 693         if (!set_ino)
 694                 return;
 695
 696         if (debugfs_read_inode_full(set_ino,
 697                         (struct ext2_inode *) &set_inode, argv[1],
 698                                     sizeof(set_inode)))
 699                 return;
 700
 701         if (ss->func(ss, argv[2], argv[3]) == 0) {
 702                 if (debugfs_write_inode_full(set_ino,
 703                              (struct ext2_inode *) &set_inode,
 704                              argv[1], sizeof(set_inode)))
 705                         return;
 706         }
 707 }
 708
 709 void do_set_block_group_descriptor(int argc, char *argv[])
 710 {
 711         const char *usage = "<bg number> <field> <value>\n"
 712                 "\t\"set_block_group_descriptor -l\" will list the names of "
 713                 "the fields in a block group descriptor\n\twhich can be set.";
 714         struct field_set_info   *table;
 715         struct field_set_info   *ss;
 716         char                    *end;
 717         void                    *edit, *target;
 718         int                     size;
 719
 720         /*
 721          * Determine whether we are editing an ext2 or ext4 block group
 722          * descriptor.  Descriptors larger than ext4_group_desc cannot
 723          * have their fields edited yet, because they do not have any
 724          * names assigned.  When that happens, this function needs to
 725          * be updated for the new descriptor struct and fields.
 726          */
 727         if (current_fs &&
 728             EXT2_DESC_SIZE(current_fs->super) >= EXT2_MIN_DESC_SIZE_64BIT) {
 729                 table = ext4_bg_fields;
 730                 edit = &set_gd4;
 731                 size = sizeof(set_gd4);
 732         } else {
 733                 table = ext2_bg_fields;
 734                 edit = &set_gd;
 735                 size = sizeof(set_gd);
 736         }
 737
 738         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 739                 print_possible_fields(table);
 740                 return;
 741         }
 742
 743         if (common_args_process(argc, argv, 4, 4, "set_block_group_descriptor",
 744                                 usage, CHECK_FS_RW))
 745                 return;
 746
 747         set_bg = strtoul(argv[1], &end, 0);
 748         if (*end) {
 749                 com_err(argv[0], 0, "invalid block group number: %s", argv[1]);
 750                 return;
 751         }
 752
 753         if (set_bg >= current_fs->group_desc_count) {
 754                 com_err(argv[0], 0, "block group number too big: %d", set_bg);
 755                 return;
 756         }
 757
 758         if ((ss = find_field(table, argv[2])) == 0) {
 759                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 760                 return;
 761         }
 762
 763         target = ext2fs_group_desc(current_fs, current_fs->group_desc, set_bg);
 764         memcpy(edit, target, size);
 765         if (ss->func(ss, argv[2], argv[3]) == 0) {
 766                 memcpy(target, edit, size);
 767                 ext2fs_mark_super_dirty(current_fs);
 768         }
 769 }
 770
 771 static errcode_t parse_mmp_clear(struct field_set_info *info,
 772                                  char *field EXT2FS_ATTR((unused)),
 773                                  char *arg EXT2FS_ATTR((unused)))
 774 {
 775         errcode_t retval;
 776
 777         retval = ext2fs_mmp_clear(current_fs);
 778         if (retval != 0)
 779                 com_err("set_mmp_value", retval, "while clearing MMP block\n");
 780         else
 781                 memcpy(info->ptr, current_fs->mmp_buf, info->size);
 782
 783         return 1; /* we don't need the MMP block written again */
 784 }
 785
 786 void do_set_mmp_value(int argc, char *argv[])
 787 {
 788 #ifdef CONFIG_MMP
 789         const char *usage = "<field> <value>\n"
 790                 "\t\"set_mmp_value -l\" will list the names of "
 791                 "MMP fields\n\twhich can be set.";
 792         static struct field_set_info *smmp;
 793         struct mmp_struct *mmp_s;
 794         errcode_t retval;
 795
 796         if (argc == 2 && strcmp(argv[1], "-l") == 0) {
 797                 print_possible_fields(mmp_fields);
 798                 return;
 799         }
 800
 801         if (check_fs_open(argv[0]))
 802                 return;
 803
 804         if (current_fs->super->s_mmp_block == 0) {
 805                 com_err(argv[0], 0, "no MMP block allocated\n");
 806                 return;
 807         }
 808
 809         if (common_args_process(argc, argv, 2, 3, "set_mmp_value",
 810                                 usage, CHECK_FS_RW))
 811                 return;
 812
 813         mmp_s = current_fs->mmp_buf;
 814         if (mmp_s == NULL) {
 815                 retval = ext2fs_get_mem(current_fs->blocksize, &mmp_s);
 816                 if (retval) {
 817                         com_err(argv[0], retval, "allocating MMP buffer\n");
 818                         return;
 819                 }
 820                 retval = ext2fs_mmp_read(current_fs,
 821                                          current_fs->super->s_mmp_block, mmp_s);
 822                 if (retval) {
 823                         com_err(argv[0], retval, "reading MMP block %llu.\n",
 824                                 (long long)current_fs->super->s_mmp_block);
 825                         ext2fs_free_mem(&mmp_s);
 826                         return;
 827                 }
 828                 current_fs->mmp_buf = mmp_s;
 829         }
 830
 831         smmp = find_field(mmp_fields, argv[1]);
 832         if (smmp == 0) {
 833                 com_err(argv[0], 0, "invalid field specifier: %s", argv[1]);
 834                 return;
 835         }
 836
 837         set_mmp = *mmp_s;
 838         if (smmp->func(smmp, argv[1], argv[2]) == 0) {
 839                 ext2fs_mmp_write(current_fs, current_fs->super->s_mmp_block,
 840                                  &set_mmp);
 841                 *mmp_s = set_mmp;
 842         }
 843 #else
 844         fprintf(stdout, "MMP is unsupported, please recompile with "
 845                         "--enable-mmp\n");
 846 #endif
 847 }
 848