lib/ext2fs/read_bb.c

   1 /*
   2  * read_bb --- read the bad blocks inode
   3  *
   4  * Copyright (C) 1994 Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Library
   8  * General Public License, version 2.
   9  * %End-Header%
  10  */
  11
  12 #include "config.h"
  13 #include <stdio.h>
  14 #include <string.h>
  15 #if HAVE_UNISTD_H
  16 #include <unistd.h>
  17 #endif
  18 #include <fcntl.h>
  19 #include <time.h>
  20 #if HAVE_SYS_STAT_H
  21 #include <sys/stat.h>
  22 #endif
  23 #if HAVE_SYS_TYPES_H
  24 #include <sys/types.h>
  25 #endif
  26
  27 #include "ext2_fs.h"
  28 #include "ext2fs.h"
  29
  30 struct read_bb_record {
  31         ext2_badblocks_list     bb_list;
  32         errcode_t       err;
  33 };
  34
  35 /*
  36  * Helper function for ext2fs_read_bb_inode()
  37  */
  38 #ifdef __TURBOC__
  39  #pragma argsused
  40 #endif
  41 static int mark_bad_block(ext2_filsys fs, blk_t *block_nr,
  42                           e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
  43                           blk_t ref_block EXT2FS_ATTR((unused)),
  44                           int ref_offset EXT2FS_ATTR((unused)),
  45                           void *priv_data)
  46 {
  47         struct read_bb_record *rb = (struct read_bb_record *) priv_data;
  48
  49         if (blockcnt < 0)
  50                 return 0;
  51
  52         if ((*block_nr < fs->super->s_first_data_block) ||
  53             (*block_nr >= ext2fs_blocks_count(fs->super)))
  54                 return 0;       /* Ignore illegal blocks */
  55
  56         rb->err = ext2fs_badblocks_list_add(rb->bb_list, *block_nr);
  57         if (rb->err)
  58                 return BLOCK_ABORT;
  59         return 0;
  60 }
  61
  62 /*
  63  * Reads the current bad blocks from the bad blocks inode.
  64  */
  65 errcode_t ext2fs_read_bb_inode(ext2_filsys fs, ext2_badblocks_list *bb_list)
  66 {
  67         errcode_t       retval;
  68         struct read_bb_record rb;
  69         struct ext2_inode inode;
  70         blk_t   numblocks;
  71
  72         EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
  73
  74         if (!*bb_list) {
  75                 retval = ext2fs_read_inode(fs, EXT2_BAD_INO, &inode);
  76                 if (retval)
  77                         return retval;
  78                 numblocks = inode.i_blocks;
  79                 if (!((fs->super->s_feature_ro_compat &
  80                        EXT4_FEATURE_RO_COMPAT_HUGE_FILE) &&
  81                       (inode.i_flags & EXT4_HUGE_FILE_FL)))
  82                         numblocks = numblocks / (fs->blocksize / 512);
  83                 numblocks += 20;
  84                 if (numblocks < 50)
  85                         numblocks = 50;
  86                 if (numblocks > 50000)
  87                         numblocks = 500;
  88                 retval = ext2fs_badblocks_list_create(bb_list, numblocks);
  89                 if (retval)
  90                         return retval;
  91         }
  92
  93         rb.bb_list = *bb_list;
  94         rb.err = 0;
  95         retval = ext2fs_block_iterate2(fs, EXT2_BAD_INO, BLOCK_FLAG_READ_ONLY,
  96                                        0, mark_bad_block, &rb);
  97         if (retval)
  98                 return retval;
  99
 100         return rb.err;
 101 }
 102
 103