lib/ext2fs/bb_inode.c

   1 /*
   2  * bb_inode.c --- routines to update the bad block inode.
   3  *
   4  * WARNING: This routine modifies a lot of state in the filesystem; if
   5  * this routine returns an error, the bad block inode may be in an
   6  * inconsistent state.
   7  *
   8  * Copyright (C) 1994, 1995 Theodore Ts'o.
   9  *
  10  * %Begin-Header%
  11  * This file may be redistributed under the terms of the GNU Public
  12  * License.
  13  * %End-Header%
  14  */
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18 #if HAVE_UNISTD_H
  19 #include <unistd.h>
  20 #endif
  21 #include <fcntl.h>
  22 #include <time.h>
  23 #if HAVE_SYS_STAT_H
  24 #include <sys/stat.h>
  25 #endif
  26 #if HAVE_SYS_TYPES_H
  27 #include <sys/types.h>
  28 #endif
  29
  30 #include "ext2_fs.h"
  31 #include "ext2fs.h"
  32
  33 struct set_badblock_record {
  34         ext2_badblocks_iterate  bb_iter;
  35         int             bad_block_count;
  36         blk_t           *ind_blocks;
  37         int             max_ind_blocks;
  38         int             ind_blocks_size;
  39         int             ind_blocks_ptr;
  40         char            *block_buf;
  41         errcode_t       err;
  42 };
  43
  44 static int set_bad_block_proc(ext2_filsys fs, blk_t *block_nr,
  45                               e2_blkcnt_t blockcnt,
  46                               blk_t ref_block, int ref_offset,
  47                               void *priv_data);
  48 static int clear_bad_block_proc(ext2_filsys fs, blk_t *block_nr,
  49                                 e2_blkcnt_t blockcnt,
  50                                 blk_t ref_block, int ref_offset,
  51                                 void *priv_data);
  52
  53 /*
  54  * Given a bad blocks bitmap, update the bad blocks inode to reflect
  55  * the map.
  56  */
  57 errcode_t ext2fs_update_bb_inode(ext2_filsys fs, ext2_badblocks_list bb_list)
  58 {
  59         errcode_t                       retval;
  60         struct set_badblock_record      rec;
  61         struct ext2_inode               inode;
  62
  63         EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
  64
  65         if (!fs->block_map)
  66                 return EXT2_ET_NO_BLOCK_BITMAP;
  67
  68         rec.bad_block_count = 0;
  69         rec.ind_blocks_size = rec.ind_blocks_ptr = 0;
  70         rec.max_ind_blocks = 10;
  71         retval = ext2fs_get_mem(rec.max_ind_blocks * sizeof(blk_t),
  72                                 (void **) &rec.ind_blocks);
  73         if (retval)
  74                 return retval;
  75         memset(rec.ind_blocks, 0, rec.max_ind_blocks * sizeof(blk_t));
  76         retval = ext2fs_get_mem(fs->blocksize, (void **) &rec.block_buf);
  77         if (retval)
  78                 goto cleanup;
  79         memset(rec.block_buf, 0, fs->blocksize);
  80         rec.err = 0;
  81
  82         /*
  83          * First clear the old bad blocks (while saving the indirect blocks)
  84          */
  85         retval = ext2fs_block_iterate2(fs, EXT2_BAD_INO,
  86                                        BLOCK_FLAG_DEPTH_TRAVERSE, 0,
  87                                        clear_bad_block_proc, &rec);
  88         if (retval)
  89                 goto cleanup;
  90         if (rec.err) {
  91                 retval = rec.err;
  92                 goto cleanup;
  93         }
  94
  95         /*
  96          * Now set the bad blocks!
  97          *
  98          * First, mark the bad blocks as used.  This prevents a bad
  99          * block from being used as an indirecto block for the bad
 100          * block inode (!).
 101          */
 102         if (bb_list) {
 103                 retval = ext2fs_badblocks_list_iterate_begin(bb_list,
 104                                                              &rec.bb_iter);
 105                 if (retval)
 106                         goto cleanup;
 107                 retval = ext2fs_block_iterate2(fs, EXT2_BAD_INO,
 108                                                BLOCK_FLAG_APPEND, 0,
 109                                                set_bad_block_proc, &rec);
 110                 ext2fs_badblocks_list_iterate_end(rec.bb_iter);
 111                 if (retval)
 112                         goto cleanup;
 113                 if (rec.err) {
 114                         retval = rec.err;
 115                         goto cleanup;
 116                 }
 117         }
 118
 119         /*
 120          * Update the bad block inode's mod time and block count
 121          * field.
 122          */
 123         retval = ext2fs_read_inode(fs, EXT2_BAD_INO, &inode);
 124         if (retval)
 125                 goto cleanup;
 126
 127         inode.i_atime = inode.i_mtime = time(0);
 128         if (!inode.i_ctime)
 129                 inode.i_ctime = time(0);
 130         inode.i_blocks = rec.bad_block_count * (fs->blocksize / 512);
 131         inode.i_size = rec.bad_block_count * fs->blocksize;
 132
 133         retval = ext2fs_write_inode(fs, EXT2_BAD_INO, &inode);
 134         if (retval)
 135                 goto cleanup;
 136
 137 cleanup:
 138         ext2fs_free_mem((void **) &rec.ind_blocks);
 139         ext2fs_free_mem((void **) &rec.block_buf);
 140         return retval;
 141 }
 142
 143 /*
 144  * Helper function for update_bb_inode()
 145  *
 146  * Clear the bad blocks in the bad block inode, while saving the
 147  * indirect blocks.
 148  */
 149 #ifdef __TURBOC__
 150  #pragma argsused
 151 #endif
 152 static int clear_bad_block_proc(ext2_filsys fs, blk_t *block_nr,
 153                                 e2_blkcnt_t blockcnt,
 154                                 blk_t ref_block, int ref_offset,
 155                                 void *priv_data)
 156 {
 157         struct set_badblock_record *rec = (struct set_badblock_record *)
 158                 priv_data;
 159         errcode_t       retval;
 160         unsigned long   old_size;
 161
 162         if (!*block_nr)
 163                 return 0;
 164
 165         /*
 166          * If the block number is outrageous, clear it and ignore it.
 167          */
 168         if (*block_nr >= fs->super->s_blocks_count ||
 169             *block_nr < fs->super->s_first_data_block) {
 170                 *block_nr = 0;
 171                 return BLOCK_CHANGED;
 172         }
 173
 174         if (blockcnt < 0) {
 175                 if (rec->ind_blocks_size >= rec->max_ind_blocks) {
 176                         old_size = rec->max_ind_blocks * sizeof(blk_t);
 177                         rec->max_ind_blocks += 10;
 178                         retval = ext2fs_resize_mem(old_size,
 179                                    rec->max_ind_blocks * sizeof(blk_t),
 180                                    (void **) &rec->ind_blocks);
 181                         if (retval) {
 182                                 rec->max_ind_blocks -= 10;
 183                                 rec->err = retval;
 184                                 return BLOCK_ABORT;
 185                         }
 186                 }
 187                 rec->ind_blocks[rec->ind_blocks_size++] = *block_nr;
 188         }
 189
 190         /*
 191          * Mark the block as unused, and update accounting information
 192          */
 193         ext2fs_block_alloc_stats(fs, *block_nr, -1);
 194
 195         *block_nr = 0;
 196         return BLOCK_CHANGED;
 197 }
 198
 199
 200 /*
 201  * Helper function for update_bb_inode()
 202  *
 203  * Set the block list in the bad block inode, using the supplied bitmap.
 204  */
 205 #ifdef __TURBOC__
 206  #pragma argsused
 207 #endif
 208 static int set_bad_block_proc(ext2_filsys fs, blk_t *block_nr,
 209                               e2_blkcnt_t blockcnt, blk_t ref_block,
 210                               int ref_offset, void *priv_data)
 211 {
 212         struct set_badblock_record *rec = (struct set_badblock_record *)
 213                 priv_data;
 214         errcode_t       retval;
 215         blk_t           blk;
 216
 217         if (blockcnt >= 0) {
 218                 /*
 219                  * Get the next bad block.
 220                  */
 221                 if (!ext2fs_badblocks_list_iterate(rec->bb_iter, &blk))
 222                         return BLOCK_ABORT;
 223                 rec->bad_block_count++;
 224         } else {
 225                 /*
 226                  * An indirect block; fetch a block from the
 227                  * previously used indirect block list.  The block
 228                  * most be not marked as used; if so, get another one.
 229                  * If we run out of reserved indirect blocks, allocate
 230                  * a new one.
 231                  */
 232         retry:
 233                 if (rec->ind_blocks_ptr < rec->ind_blocks_size) {
 234                         blk = rec->ind_blocks[rec->ind_blocks_ptr++];
 235                         if (ext2fs_test_block_bitmap(fs->block_map, blk))
 236                                 goto retry;
 237                 } else {
 238                         retval = ext2fs_new_block(fs, 0, 0, &blk);
 239                         if (retval) {
 240                                 rec->err = retval;
 241                                 return BLOCK_ABORT;
 242                         }
 243                 }
 244                 retval = io_channel_write_blk(fs->io, blk, 1, rec->block_buf);
 245                 if (retval) {
 246                         rec->err = retval;
 247                         return BLOCK_ABORT;
 248                 }
 249         }
 250
 251         /*
 252          * Update block counts
 253          */
 254         ext2fs_block_alloc_stats(fs, blk, +1);
 255
 256         *block_nr = blk;
 257         return BLOCK_CHANGED;
 258 }
 259
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