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 <stdio.h>
  21 #include <unistd.h>
  22 #include <stdlib.h>
  23 #include <ctype.h>
  24 #include <string.h>
  25 #include <strings.h>
  26 #include <time.h>
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29 #ifdef HAVE_ERRNO_H
  30 #include <errno.h>
  31 #endif
  32 #if HAVE_STRINGS_H
  33 #include <strings.h>
  34 #endif
  35 #include <fcntl.h>
  36 #include <utime.h>
  37
  38 #include "debugfs.h"
  39 #include "uuid/uuid.h"
  40 #include "e2p/e2p.h"
  41
  42 static struct ext2_super_block set_sb;
  43 static struct ext2_inode_large set_inode;
  44 static struct ext2_group_desc set_gd;
  45 static struct ext4_group_desc set_gd4;
  46 static dgrp_t set_bg;
  47 static ext2_ino_t set_ino;
  48 static int array_idx;
  49
  50 #define FLAG_ARRAY      0x0001
  51
  52 struct field_set_info {
  53         const char      *name;
  54         void    *ptr;
  55         void    *ptr2;
  56         unsigned int    size;
  57         errcode_t (*func)(struct field_set_info *info, char *field, char *arg);
  58         int flags;
  59         int max_idx;
  60 };
  61
  62 static errcode_t parse_uint(struct field_set_info *info, char *field, char *arg);
  63 static errcode_t parse_int(struct field_set_info *info, char *field, char *arg);
  64 static errcode_t parse_string(struct field_set_info *info, char *field, char *arg);
  65 static errcode_t parse_uuid(struct field_set_info *info, char *field, char *arg);
  66 static errcode_t parse_hashalg(struct field_set_info *info, char *field, char *arg);
  67 static errcode_t parse_time(struct field_set_info *info, char *field, char *arg);
  68 static errcode_t parse_bmap(struct field_set_info *info, char *field, char *arg);
  69 static errcode_t parse_gd_csum(struct field_set_info *info, char *field, char *arg);
  70
  71 static struct field_set_info super_fields[] = {
  72         { "inodes_count", &set_sb.s_inodes_count, NULL, 4, parse_uint },
  73         { "blocks_count", &set_sb.s_blocks_count, &set_sb.s_blocks_count_hi,
  74                 4, parse_uint },
  75         { "r_blocks_count", &set_sb.s_r_blocks_count,
  76                 &set_sb.s_r_blocks_count_hi, 4, parse_uint },
  77         { "free_blocks_count", &set_sb.s_free_blocks_count,
  78                 &set_sb.s_free_blocks_hi, 4, parse_uint },
  79         { "free_inodes_count", &set_sb.s_free_inodes_count, NULL, 4, parse_uint },
  80         { "first_data_block", &set_sb.s_first_data_block, NULL, 4, parse_uint },
  81         { "log_block_size", &set_sb.s_log_block_size, NULL, 4, parse_uint },
  82         { "log_cluster_size", &set_sb.s_log_cluster_size, NULL, 4, parse_int },
  83         { "blocks_per_group", &set_sb.s_blocks_per_group, NULL, 4, parse_uint },
  84         { "clusters_per_group", &set_sb.s_clusters_per_group, NULL, 4, parse_uint },
  85         { "inodes_per_group", &set_sb.s_inodes_per_group, NULL, 4, parse_uint },
  86         { "mtime", &set_sb.s_mtime, NULL, 4, parse_time },
  87         { "wtime", &set_sb.s_wtime, NULL, 4, parse_time },
  88         { "mnt_count", &set_sb.s_mnt_count, NULL, 2, parse_uint },
  89         { "max_mnt_count", &set_sb.s_max_mnt_count, NULL, 2, parse_int },
  90         /* s_magic */
  91         { "state", &set_sb.s_state, NULL, 2, parse_uint },
  92         { "errors", &set_sb.s_errors, NULL, 2, parse_uint },
  93         { "minor_rev_level", &set_sb.s_minor_rev_level, NULL, 2, parse_uint },
  94         { "lastcheck", &set_sb.s_lastcheck, NULL, 4, parse_time },
  95         { "checkinterval", &set_sb.s_checkinterval, NULL, 4, parse_uint },
  96         { "creator_os", &set_sb.s_creator_os, NULL, 4, parse_uint },
  97         { "rev_level", &set_sb.s_rev_level, NULL, 4, parse_uint },
  98         { "def_resuid", &set_sb.s_def_resuid, NULL, 2, parse_uint },
  99         { "def_resgid", &set_sb.s_def_resgid, NULL, 2, parse_uint },
 100         { "first_ino", &set_sb.s_first_ino, NULL, 4, parse_uint },
 101         { "inode_size", &set_sb.s_inode_size, NULL, 2, parse_uint },
 102         { "block_group_nr", &set_sb.s_block_group_nr, NULL, 2, parse_uint },
 103         { "feature_compat", &set_sb.s_feature_compat, NULL, 4, parse_uint },
 104         { "feature_incompat", &set_sb.s_feature_incompat, NULL, 4, parse_uint },
 105         { "feature_ro_compat", &set_sb.s_feature_ro_compat, NULL, 4, parse_uint },
 106         { "uuid", &set_sb.s_uuid, NULL, 16, parse_uuid },
 107         { "volume_name",  &set_sb.s_volume_name, NULL, 16, parse_string },
 108         { "last_mounted",  &set_sb.s_last_mounted, NULL, 64, parse_string },
 109         { "lastcheck",  &set_sb.s_lastcheck, NULL, 4, parse_uint },
 110         { "algorithm_usage_bitmap", &set_sb.s_algorithm_usage_bitmap, NULL,
 111                   4, parse_uint },
 112         { "prealloc_blocks", &set_sb.s_prealloc_blocks, NULL, 1, parse_uint },
 113         { "prealloc_dir_blocks", &set_sb.s_prealloc_dir_blocks, NULL, 1,
 114                   parse_uint },
 115         { "reserved_gdt_blocks", &set_sb.s_reserved_gdt_blocks, NULL, 2,
 116                   parse_uint },
 117         { "journal_uuid", &set_sb.s_journal_uuid, NULL, 16, parse_uuid },
 118         { "journal_inum", &set_sb.s_journal_inum, NULL, 4, parse_uint },
 119         { "journal_dev", &set_sb.s_journal_dev, NULL, 4, parse_uint },
 120         { "last_orphan", &set_sb.s_last_orphan, NULL, 4, parse_uint },
 121         { "hash_seed", &set_sb.s_hash_seed, NULL, 16, parse_uuid },
 122         { "def_hash_version", &set_sb.s_def_hash_version, NULL, 1, parse_hashalg },
 123         { "jnl_backup_type", &set_sb.s_jnl_backup_type, NULL, 1, parse_uint },
 124         { "desc_size", &set_sb.s_desc_size, NULL, 2, parse_uint },
 125         { "default_mount_opts", &set_sb.s_default_mount_opts, NULL, 4, parse_uint },
 126         { "first_meta_bg", &set_sb.s_first_meta_bg, NULL, 4, parse_uint },
 127         { "mkfs_time", &set_sb.s_mkfs_time, NULL, 4, parse_time },
 128         { "jnl_blocks", &set_sb.s_jnl_blocks[0], NULL, 4, parse_uint, FLAG_ARRAY,
 129           17 },
 130         { "min_extra_isize", &set_sb.s_min_extra_isize, NULL, 2, parse_uint },
 131         { "want_extra_isize", &set_sb.s_want_extra_isize, NULL, 2, parse_uint },
 132         { "flags", &set_sb.s_flags, NULL, 4, parse_uint },
 133         { "raid_stride", &set_sb.s_raid_stride, NULL, 2, parse_uint },
 134         { "min_extra_isize", &set_sb.s_min_extra_isize, NULL, 4, parse_uint },
 135         { "mmp_interval", &set_sb.s_mmp_interval, NULL, 2, parse_uint },
 136         { "mmp_block", &set_sb.s_mmp_block, NULL, 8, parse_uint },
 137         { "raid_stripe_width", &set_sb.s_raid_stripe_width, NULL, 4, parse_uint },
 138         { "log_groups_per_flex", &set_sb.s_log_groups_per_flex, NULL, 1, parse_uint },
 139         { "kbytes_written", &set_sb.s_kbytes_written, NULL, 8, parse_uint },
 140         { "snapshot_inum", &set_sb.s_snapshot_inum, NULL, 4, parse_uint },
 141         { "snapshot_id", &set_sb.s_snapshot_id, NULL, 4, parse_uint },
 142         { "snapshot_r_blocks_count", &set_sb.s_snapshot_r_blocks_count,
 143           NULL, 8, parse_uint },
 144         { "snapshot_list", &set_sb.s_snapshot_list, NULL, 4, parse_uint },
 145         { "mount_opts",  &set_sb.s_mount_opts, NULL, 64, parse_string },
 146         { "usr_quota_inum", &set_sb.s_usr_quota_inum, NULL, 4, parse_uint },
 147         { "grp_quota_inum", &set_sb.s_grp_quota_inum, NULL, 4, parse_uint },
 148         { "overhead_blocks", &set_sb.s_overhead_blocks, NULL, 4, parse_uint },
 149         { "checksum", &set_sb.s_checksum, NULL, 4, parse_uint },
 150         { 0, 0, 0, 0 }
 151 };
 152
 153 static struct field_set_info inode_fields[] = {
 154         { "inodes_count", &set_sb.s_inodes_count, NULL, 4, parse_uint },
 155         { "mode", &set_inode.i_mode, NULL, 2, parse_uint },
 156         { "uid", &set_inode.i_uid, &set_inode.osd2.linux2.l_i_uid_high,
 157                 2, parse_uint },
 158         { "size", &set_inode.i_size, &set_inode.i_size_high, 4, parse_uint },
 159         { "atime", &set_inode.i_atime, NULL, 4, parse_time },
 160         { "ctime", &set_inode.i_ctime, NULL, 4, parse_time },
 161         { "mtime", &set_inode.i_mtime, NULL, 4, parse_time },
 162         { "dtime", &set_inode.i_dtime, NULL, 4, parse_time },
 163         { "gid", &set_inode.i_gid, &set_inode.osd2.linux2.l_i_gid_high,
 164                 2, parse_uint },
 165         { "links_count", &set_inode.i_links_count, NULL, 2, parse_uint },
 166         /* Special case: i_blocks is 4 bytes, i_blocks_high is 2 bytes */
 167         { "blocks", &set_inode.i_blocks, &set_inode.osd2.linux2.l_i_blocks_hi,
 168                 6, parse_uint },
 169         { "flags", &set_inode.i_flags, NULL, 4, parse_uint },
 170         { "version", &set_inode.osd1.linux1.l_i_version,
 171                 &set_inode.i_version_hi, 4, parse_uint },
 172         { "translator", &set_inode.osd1.hurd1.h_i_translator, NULL, 4, parse_uint },
 173         { "block", &set_inode.i_block[0], NULL, 4, parse_uint, FLAG_ARRAY,
 174           EXT2_NDIR_BLOCKS },
 175         { "block[IND]", &set_inode.i_block[EXT2_IND_BLOCK], NULL, 4, parse_uint },
 176         { "block[DIND]", &set_inode.i_block[EXT2_DIND_BLOCK], NULL, 4, parse_uint },
 177         { "block[TIND]", &set_inode.i_block[EXT2_TIND_BLOCK], NULL, 4, parse_uint },
 178         { "generation", &set_inode.i_generation, NULL, 4, parse_uint },
 179         /* Special case: i_file_acl_high is 2 bytes */
 180         { "file_acl", &set_inode.i_file_acl,
 181                 &set_inode.osd2.linux2.l_i_file_acl_high, 6, parse_uint },
 182         { "dir_acl", &set_inode.i_dir_acl, NULL, 4, parse_uint },
 183         { "faddr", &set_inode.i_faddr, NULL, 4, parse_uint },
 184         { "frag", &set_inode.osd2.hurd2.h_i_frag, NULL, 1, parse_uint },
 185         { "fsize", &set_inode.osd2.hurd2.h_i_fsize, NULL, 1, parse_uint },
 186         { "checksum", &set_inode.osd2.linux2.l_i_checksum_lo,
 187                 &set_inode.i_checksum_hi, 2, parse_uint },
 188         { "author", &set_inode.osd2.hurd2.h_i_author, NULL,
 189                 4, parse_uint },
 190         { "extra_isize", &set_inode.i_extra_isize, NULL,
 191                 2, parse_uint },
 192         { "ctime_extra", &set_inode.i_ctime_extra, NULL,
 193                 4, parse_uint },
 194         { "mtime_extra", &set_inode.i_mtime_extra, NULL,
 195                 4, parse_uint },
 196         { "atime_extra", &set_inode.i_atime_extra, NULL,
 197                 4, parse_uint },
 198         { "crtime", &set_inode.i_crtime, NULL, 4, parse_uint },
 199         { "crtime_extra", &set_inode.i_crtime_extra, NULL,
 200                 4, parse_uint },
 201         { "bmap", NULL, NULL, 4, parse_bmap, FLAG_ARRAY },
 202         { 0, 0, 0, 0 }
 203 };
 204
 205 static struct field_set_info ext2_bg_fields[] = {
 206         { "block_bitmap", &set_gd.bg_block_bitmap, NULL, 4, parse_uint },
 207         { "inode_bitmap", &set_gd.bg_inode_bitmap, NULL, 4, parse_uint },
 208         { "inode_table", &set_gd.bg_inode_table, NULL, 4, parse_uint },
 209         { "free_blocks_count", &set_gd.bg_free_blocks_count, NULL, 2, parse_uint },
 210         { "free_inodes_count", &set_gd.bg_free_inodes_count, NULL, 2, parse_uint },
 211         { "used_dirs_count", &set_gd.bg_used_dirs_count, NULL, 2, parse_uint },
 212         { "flags", &set_gd.bg_flags, NULL, 2, parse_uint },
 213         { "itable_unused", &set_gd.bg_itable_unused, NULL, 2, parse_uint },
 214         { "checksum", &set_gd.bg_checksum, NULL, 2, parse_gd_csum },
 215         { 0, 0, 0, 0 }
 216 };
 217
 218 static struct field_set_info ext4_bg_fields[] = {
 219         { "block_bitmap", &set_gd4.bg_block_bitmap,
 220                 &set_gd4.bg_block_bitmap_hi, 4, parse_uint },
 221         { "inode_bitmap", &set_gd4.bg_inode_bitmap,
 222                 &set_gd4.bg_inode_bitmap_hi, 4, parse_uint },
 223         { "inode_table", &set_gd4.bg_inode_table,
 224                 &set_gd4.bg_inode_table_hi, 4, parse_uint },
 225         { "free_blocks_count", &set_gd4.bg_free_blocks_count,
 226                 &set_gd4.bg_free_blocks_count_hi, 2, parse_uint },
 227         { "free_inodes_count", &set_gd4.bg_free_inodes_count,
 228                 &set_gd4.bg_free_inodes_count_hi, 2, parse_uint },
 229         { "used_dirs_count", &set_gd4.bg_used_dirs_count,
 230                 &set_gd4.bg_used_dirs_count_hi, 2, parse_uint },
 231         { "flags", &set_gd4.bg_flags, NULL, 2, parse_uint },
 232         { "exclude_bitmap", &set_gd4.bg_exclude_bitmap_lo,
 233                 &set_gd4.bg_exclude_bitmap_hi, 4, parse_uint },
 234         { "block_bitmap_csum", &set_gd4.bg_block_bitmap_csum_lo,
 235                 &set_gd4.bg_block_bitmap_csum_hi, 2, parse_uint },
 236         { "inode_bitmap_csum", &set_gd4.bg_inode_bitmap_csum_lo,
 237                 &set_gd4.bg_inode_bitmap_csum_hi, 2, parse_uint },
 238         { "itable_unused", &set_gd4.bg_itable_unused,
 239                 &set_gd4.bg_itable_unused_hi, 2, parse_uint },
 240         { "checksum", &set_gd4.bg_checksum, NULL, 2, parse_gd_csum },
 241         { 0, 0, 0, 0 }
 242 };
 243
 244 static int check_suffix(const char *field)
 245 {
 246         int len = strlen(field);
 247
 248         if (len <= 3)
 249                 return 0;
 250         field += len-3;
 251         if (!strcmp(field, "_lo"))
 252                 return 1;
 253         if (!strcmp(field, "_hi"))
 254                 return 2;
 255         return 0;
 256 }
 257
 258 static struct field_set_info *find_field(struct field_set_info *fields,
 259                                          char *field)
 260 {
 261         struct field_set_info *ss;
 262         const char      *prefix;
 263         char            *arg, *delim, *idx, *tmp;
 264         int             suffix, prefix_len;
 265
 266         if (fields == super_fields)
 267                 prefix = "s_";
 268         else if (fields == inode_fields)
 269                 prefix = "i_";
 270         else
 271                 prefix = "bg_";
 272         prefix_len = strlen(prefix);
 273         if (strncmp(field, prefix, prefix_len) == 0)
 274                 field += prefix_len;
 275
 276         arg = malloc(strlen(field)+1);
 277         if (!arg)
 278                 return NULL;
 279         strcpy(arg, field);
 280
 281         idx = strchr(arg, '[');
 282         if (idx) {
 283                 *idx++ = 0;
 284                 delim = idx + strlen(idx) - 1;
 285                 if (!*idx || *delim != ']')
 286                         idx = 0;
 287                 else
 288                         *delim = 0;
 289         }
 290         /*
 291          * Can we parse the number?
 292          */
 293         if (idx) {
 294                 array_idx = strtol(idx, &tmp, 0);
 295                 if (*tmp)
 296                         idx = 0;
 297         }
 298
 299         /*
 300          * If there is a valid _hi or a _lo suffix, strip it off
 301          */
 302         suffix = check_suffix(arg);
 303         if (suffix > 0)
 304                 arg[strlen(arg)-3] = 0;
 305
 306         for (ss = fields ; ss->name ; ss++) {
 307                 if (suffix && ss->ptr2 == 0)
 308                         continue;
 309                 if (ss->flags & FLAG_ARRAY) {
 310                         if (!idx || (strcmp(ss->name, arg) != 0))
 311                                 continue;
 312                         if (ss->max_idx > 0 && array_idx >= ss->max_idx)
 313                                 continue;
 314                 } else {
 315                         if (strcmp(ss->name, arg) != 0)
 316                                 continue;
 317                 }
 318                 free(arg);
 319                 return ss;
 320         }
 321         free(arg);
 322         return NULL;
 323 }
 324
 325 /*
 326  * Note: info->size == 6 is special; this means a base size 4 bytes,
 327  * and secondiory (high) size of 2 bytes.  This is needed for the
 328  * special case of i_blocks_high and i_file_acl_high.
 329  */
 330 static errcode_t parse_uint(struct field_set_info *info, char *field,
 331                             char *arg)
 332 {
 333         unsigned long long n, num, mask, limit;
 334         int suffix = check_suffix(field);
 335         char *tmp;
 336         void *field1 = info->ptr, *field2 = info->ptr2;
 337         int size = (info->size == 6) ? 4 : info->size;
 338         union {
 339                 __u64   *ptr64;
 340                 __u32   *ptr32;
 341                 __u16   *ptr16;
 342                 __u8    *ptr8;
 343         } u;
 344
 345         if (suffix == 1)
 346                 field2 = 0;
 347         if (suffix == 2) {
 348                 field1 = field2;
 349                 field2 = 0;
 350         }
 351
 352         u.ptr8 = (__u8 *) field1;
 353         if (info->flags & FLAG_ARRAY)
 354                 u.ptr8 += array_idx * info->size;
 355
 356         errno = 0;
 357         num = STRTOULL(arg, &tmp, 0);
 358         if (*tmp || errno) {
 359                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 360                         arg, info->name);
 361                 return EINVAL;
 362         }
 363         mask = ~0ULL >> ((8 - size) * 8);
 364         limit = ~0ULL >> ((8 - info->size) * 8);
 365         if (field2 && info->size != 6)
 366                 limit = ~0ULL >> ((8 - info->size*2) * 8);
 367
 368         if (num > limit) {
 369                 fprintf(stderr, "Value '%s' exceeds field %s maximum %llu.\n",
 370                         arg, info->name, limit);
 371                 return EINVAL;
 372         }
 373         n = num & mask;
 374         switch (size) {
 375         case 8:
 376                 *u.ptr64 = n;
 377                 break;
 378         case 4:
 379                 *u.ptr32 = n;
 380                 break;
 381         case 2:
 382                 *u.ptr16 = n;
 383                 break;
 384         case 1:
 385                 *u.ptr8 = n;
 386                 break;
 387         }
 388         if (!field2)
 389                 return 0;
 390         n = num >> (size*8);
 391         u.ptr8 = (__u8 *) field2;
 392         if (info->size == 6)
 393                 size = 2;
 394         switch (size) {
 395         case 8:
 396                 *u.ptr64 = n;
 397                 break;
 398         case 4:
 399                 *u.ptr32 = n;
 400                 break;
 401         case 2:
 402                 *u.ptr16 = n;
 403                 break;
 404         case 1:
 405                 *u.ptr8 = n;
 406                 break;
 407         }
 408         return 0;
 409 }
 410
 411 static errcode_t parse_int(struct field_set_info *info, char *field, char *arg)
 412 {
 413         long    num;
 414         char *tmp;
 415         __s32   *ptr32;
 416         __s16   *ptr16;
 417         __s8    *ptr8;
 418
 419         num = strtol(arg, &tmp, 0);
 420         if (*tmp) {
 421                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 422                         arg, info->name);
 423                 return EINVAL;
 424         }
 425         switch (info->size) {
 426         case 4:
 427                 ptr32 = (__s32 *) info->ptr;
 428                 *ptr32 = num;
 429                 break;
 430         case 2:
 431                 ptr16 = (__s16 *) info->ptr;
 432                 *ptr16 = num;
 433                 break;
 434         case 1:
 435                 ptr8 = (__s8 *) info->ptr;
 436                 *ptr8 = num;
 437                 break;
 438         }
 439         return 0;
 440 }
 441
 442 static errcode_t parse_string(struct field_set_info *info, char *field,
 443                               char *arg)
 444 {
 445         char    *cp = (char *) info->ptr;
 446
 447         if (strlen(arg) >= info->size) {
 448                 fprintf(stderr, "Error maximum size for %s is %d.\n",
 449                         info->name, info->size);
 450                 return EINVAL;
 451         }
 452         strcpy(cp, arg);
 453         return 0;
 454 }
 455
 456 static errcode_t parse_time(struct field_set_info *info, char *field, char *arg)
 457 {
 458         time_t          t;
 459         __u32           *ptr32;
 460
 461         ptr32 = (__u32 *) info->ptr;
 462
 463         t = string_to_time(arg);
 464
 465         if (t == ((time_t) -1)) {
 466                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 467                         arg, info->name);
 468                 return EINVAL;
 469         }
 470         *ptr32 = t;
 471         return 0;
 472 }
 473
 474 static errcode_t parse_uuid(struct field_set_info *info, char *field, char *arg)
 475 {
 476         unsigned char * p = (unsigned char *) info->ptr;
 477
 478         if ((strcasecmp(arg, "null") == 0) ||
 479             (strcasecmp(arg, "clear") == 0)) {
 480                 uuid_clear(p);
 481         } else if (strcasecmp(arg, "time") == 0) {
 482                 uuid_generate_time(p);
 483         } else if (strcasecmp(arg, "random") == 0) {
 484                 uuid_generate(p);
 485         } else if (uuid_parse(arg, p)) {
 486                 fprintf(stderr, "Invalid UUID format: %s\n", arg);
 487                 return EINVAL;
 488         }
 489         return 0;
 490 }
 491
 492 static errcode_t parse_hashalg(struct field_set_info *info, char *field,
 493                                char *arg)
 494 {
 495         int     hashv;
 496         unsigned char   *p = (unsigned char *) info->ptr;
 497
 498         hashv = e2p_string2hash(arg);
 499         if (hashv < 0) {
 500                 fprintf(stderr, "Invalid hash algorithm: %s\n", arg);
 501                 return EINVAL;
 502         }
 503         *p = hashv;
 504         return 0;
 505 }
 506
 507 static errcode_t parse_bmap(struct field_set_info *info, char *field,
 508                             char *arg)
 509 {
 510         unsigned long   num;
 511         blk_t           blk;
 512         errcode_t       retval;
 513         char            *tmp;
 514
 515         num = strtoul(arg, &tmp, 0);
 516         if (*tmp) {
 517                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 518                         arg, info->name);
 519                 return EINVAL;
 520         }
 521         blk = num;
 522
 523         retval = ext2fs_bmap(current_fs, set_ino,
 524                              (struct ext2_inode *) &set_inode,
 525                              0, BMAP_SET, array_idx, &blk);
 526         if (retval) {
 527                 com_err("set_inode", retval, "while setting block map");
 528         }
 529         return retval;
 530 }
 531
 532 static errcode_t parse_gd_csum(struct field_set_info *info, char *field,
 533                                char *arg)
 534 {
 535
 536         if (strcmp(arg, "calc") == 0) {
 537                 ext2fs_group_desc_csum_set(current_fs, set_bg);
 538                 memcpy(&set_gd, ext2fs_group_desc(current_fs,
 539                                         current_fs->group_desc,
 540                                         set_bg),
 541                         sizeof(set_gd));
 542                 printf("Checksum set to 0x%04x\n",
 543                        ext2fs_bg_checksum(current_fs, set_bg));
 544                 return 0;
 545         }
 546
 547         return parse_uint(info, field, arg);
 548 }
 549
 550 static void print_possible_fields(struct field_set_info *fields)
 551 {
 552         struct field_set_info *ss;
 553         const char      *type, *cmd;
 554         FILE *f;
 555         char name[40], idx[40];
 556
 557         if (fields == super_fields) {
 558                 type = "Superblock";
 559                 cmd = "set_super_value";
 560         } else if (fields == inode_fields) {
 561                 type = "Inode";
 562                 cmd = "set_inode";
 563         } else {
 564                 type = "Block group descriptor";
 565                 cmd = "set_block_group";
 566         }
 567         f = open_pager();
 568
 569         fprintf(f, "%s fields supported by the %s command:\n", type, cmd);
 570
 571         for (ss = fields ; ss->name ; ss++) {
 572                 type = "unknown";
 573                 if (ss->func == parse_string)
 574                         type = "string";
 575                 else if (ss->func == parse_int)
 576                         type = "integer";
 577                 else if (ss->func == parse_uint)
 578                         type = "unsigned integer";
 579                 else if (ss->func == parse_uuid)
 580                         type = "UUID";
 581                 else if (ss->func == parse_hashalg)
 582                         type = "hash algorithm";
 583                 else if (ss->func == parse_time)
 584                         type = "date/time";
 585                 else if (ss->func == parse_bmap)
 586                         type = "set physical->logical block map";
 587                 else if (ss->func == parse_gd_csum)
 588                         type = "unsigned integer OR \"calc\"";
 589                 strcpy(name, ss->name);
 590                 if (ss->flags & FLAG_ARRAY) {
 591                         if (ss->max_idx > 0)
 592                                 sprintf(idx, "[%d]", ss->max_idx);
 593                         else
 594                                 strcpy(idx, "[]");
 595                         strcat(name, idx);
 596                 }
 597                 if (ss->ptr2)
 598                         strcat(name, "[_hi|_lo]");
 599                 fprintf(f, "\t%-25s\t%s\n", name, type);
 600         }
 601         close_pager(f);
 602 }
 603
 604
 605 void do_set_super(int argc, char *argv[])
 606 {
 607         const char *usage = "<field> <value>\n"
 608                 "\t\"set_super_value -l\" will list the names of "
 609                 "superblock fields\n\twhich can be set.";
 610         static struct field_set_info *ss;
 611
 612         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 613                 print_possible_fields(super_fields);
 614                 return;
 615         }
 616
 617         if (common_args_process(argc, argv, 3, 3, "set_super_value",
 618                                 usage, CHECK_FS_RW))
 619                 return;
 620
 621         if ((ss = find_field(super_fields, argv[1])) == 0) {
 622                 com_err(argv[0], 0, "invalid field specifier: %s", argv[1]);
 623                 return;
 624         }
 625         set_sb = *current_fs->super;
 626         if (ss->func(ss, argv[1], argv[2]) == 0) {
 627                 *current_fs->super = set_sb;
 628                 ext2fs_mark_super_dirty(current_fs);
 629         }
 630 }
 631
 632 void do_set_inode(int argc, char *argv[])
 633 {
 634         const char *usage = "<inode> <field> <value>\n"
 635                 "\t\"set_inode_field -l\" will list the names of "
 636                 "the fields in an ext2 inode\n\twhich can be set.";
 637         static struct field_set_info *ss;
 638
 639         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 640                 print_possible_fields(inode_fields);
 641                 return;
 642         }
 643
 644         if (common_args_process(argc, argv, 4, 4, "set_inode",
 645                                 usage, CHECK_FS_RW))
 646                 return;
 647
 648         if ((ss = find_field(inode_fields, argv[2])) == 0) {
 649                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 650                 return;
 651         }
 652
 653         set_ino = string_to_inode(argv[1]);
 654         if (!set_ino)
 655                 return;
 656
 657         if (debugfs_read_inode_full(set_ino,
 658                         (struct ext2_inode *) &set_inode, argv[1],
 659                                     sizeof(set_inode)))
 660                 return;
 661
 662         if (ss->func(ss, argv[2], argv[3]) == 0) {
 663                 if (debugfs_write_inode_full(set_ino,
 664                              (struct ext2_inode *) &set_inode,
 665                              argv[1], sizeof(set_inode)))
 666                         return;
 667         }
 668 }
 669
 670 void do_set_block_group_descriptor(int argc, char *argv[])
 671 {
 672         const char *usage = "<bg number> <field> <value>\n"
 673                 "\t\"set_block_group_descriptor -l\" will list the names of "
 674                 "the fields in a block group descriptor\n\twhich can be set.";
 675         struct field_set_info   *table;
 676         struct field_set_info   *ss;
 677         char                    *end;
 678         void                    *edit, *target;
 679         int                     size;
 680
 681         /*
 682          *Determine whether we are editing an ext2 or ext4 block
 683          * group descriptor
 684          */
 685         if (current_fs && current_fs->super->s_feature_incompat &
 686             EXT4_FEATURE_INCOMPAT_64BIT) {
 687                 table = ext4_bg_fields;
 688                 edit = &set_gd4;
 689                 size = sizeof(set_gd4);
 690         } else {
 691                 table = ext2_bg_fields;
 692                 edit = &set_gd;
 693                 size = sizeof(set_gd);
 694         }
 695
 696         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 697                 print_possible_fields(table);
 698                 return;
 699         }
 700
 701         if (common_args_process(argc, argv, 4, 4, "set_block_group_descriptor",
 702                                 usage, CHECK_FS_RW))
 703                 return;
 704
 705         set_bg = strtoul(argv[1], &end, 0);
 706         if (*end) {
 707                 com_err(argv[0], 0, "invalid block group number: %s", argv[1]);
 708                 return;
 709         }
 710
 711         if (set_bg >= current_fs->group_desc_count) {
 712                 com_err(argv[0], 0, "block group number too big: %d", set_bg);
 713                 return;
 714         }
 715
 716         if ((ss = find_field(table, argv[2])) == 0) {
 717                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 718                 return;
 719         }
 720
 721         target = ext2fs_group_desc(current_fs, current_fs->group_desc, set_bg);
 722         memcpy(edit, target, size);
 723         if (ss->func(ss, argv[2], argv[3]) == 0) {
 724                 memcpy(target, edit, size);
 725                 ext2fs_mark_super_dirty(current_fs);
 726         }
 727 }