1 |
62 |
marcus.erl |
/*
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2 |
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* linux/fs/ext4/resize.c
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3 |
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*
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4 |
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* Support for resizing an ext4 filesystem while it is mounted.
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5 |
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*
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6 |
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* Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com>
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7 |
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*
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8 |
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* This could probably be made into a module, because it is not often in use.
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9 |
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*/
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10 |
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11 |
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12 |
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#define EXT4FS_DEBUG
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13 |
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14 |
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#include <linux/ext4_jbd2.h>
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15 |
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16 |
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#include <linux/errno.h>
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17 |
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#include <linux/slab.h>
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18 |
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19 |
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#include "group.h"
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20 |
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21 |
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#define outside(b, first, last) ((b) < (first) || (b) >= (last))
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22 |
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#define inside(b, first, last) ((b) >= (first) && (b) < (last))
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23 |
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24 |
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static int verify_group_input(struct super_block *sb,
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25 |
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struct ext4_new_group_data *input)
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26 |
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{
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27 |
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struct ext4_sb_info *sbi = EXT4_SB(sb);
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28 |
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struct ext4_super_block *es = sbi->s_es;
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29 |
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ext4_fsblk_t start = ext4_blocks_count(es);
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30 |
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ext4_fsblk_t end = start + input->blocks_count;
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31 |
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unsigned group = input->group;
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32 |
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ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group;
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33 |
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unsigned overhead = ext4_bg_has_super(sb, group) ?
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34 |
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(1 + ext4_bg_num_gdb(sb, group) +
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35 |
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le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
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36 |
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ext4_fsblk_t metaend = start + overhead;
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37 |
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struct buffer_head *bh = NULL;
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38 |
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ext4_grpblk_t free_blocks_count, offset;
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39 |
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int err = -EINVAL;
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40 |
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41 |
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input->free_blocks_count = free_blocks_count =
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42 |
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input->blocks_count - 2 - overhead - sbi->s_itb_per_group;
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43 |
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44 |
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if (test_opt(sb, DEBUG))
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45 |
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printk(KERN_DEBUG "EXT4-fs: adding %s group %u: %u blocks "
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46 |
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"(%d free, %u reserved)\n",
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47 |
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ext4_bg_has_super(sb, input->group) ? "normal" :
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48 |
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"no-super", input->group, input->blocks_count,
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49 |
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free_blocks_count, input->reserved_blocks);
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50 |
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51 |
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ext4_get_group_no_and_offset(sb, start, NULL, &offset);
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52 |
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if (group != sbi->s_groups_count)
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53 |
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ext4_warning(sb, __FUNCTION__,
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54 |
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"Cannot add at group %u (only %lu groups)",
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55 |
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input->group, sbi->s_groups_count);
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56 |
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else if (offset != 0)
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57 |
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ext4_warning(sb, __FUNCTION__, "Last group not full");
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58 |
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else if (input->reserved_blocks > input->blocks_count / 5)
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59 |
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ext4_warning(sb, __FUNCTION__, "Reserved blocks too high (%u)",
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60 |
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input->reserved_blocks);
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61 |
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else if (free_blocks_count < 0)
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62 |
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ext4_warning(sb, __FUNCTION__, "Bad blocks count %u",
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63 |
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input->blocks_count);
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64 |
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else if (!(bh = sb_bread(sb, end - 1)))
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65 |
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ext4_warning(sb, __FUNCTION__,
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66 |
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"Cannot read last block (%llu)",
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67 |
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end - 1);
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68 |
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else if (outside(input->block_bitmap, start, end))
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69 |
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ext4_warning(sb, __FUNCTION__,
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70 |
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"Block bitmap not in group (block %llu)",
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71 |
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(unsigned long long)input->block_bitmap);
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72 |
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else if (outside(input->inode_bitmap, start, end))
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73 |
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ext4_warning(sb, __FUNCTION__,
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74 |
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"Inode bitmap not in group (block %llu)",
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75 |
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(unsigned long long)input->inode_bitmap);
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76 |
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else if (outside(input->inode_table, start, end) ||
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77 |
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outside(itend - 1, start, end))
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78 |
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ext4_warning(sb, __FUNCTION__,
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79 |
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"Inode table not in group (blocks %llu-%llu)",
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80 |
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(unsigned long long)input->inode_table, itend - 1);
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81 |
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else if (input->inode_bitmap == input->block_bitmap)
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82 |
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ext4_warning(sb, __FUNCTION__,
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83 |
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"Block bitmap same as inode bitmap (%llu)",
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84 |
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(unsigned long long)input->block_bitmap);
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85 |
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else if (inside(input->block_bitmap, input->inode_table, itend))
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86 |
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ext4_warning(sb, __FUNCTION__,
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87 |
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"Block bitmap (%llu) in inode table (%llu-%llu)",
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88 |
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(unsigned long long)input->block_bitmap,
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89 |
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(unsigned long long)input->inode_table, itend - 1);
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90 |
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else if (inside(input->inode_bitmap, input->inode_table, itend))
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91 |
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ext4_warning(sb, __FUNCTION__,
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92 |
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"Inode bitmap (%llu) in inode table (%llu-%llu)",
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93 |
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(unsigned long long)input->inode_bitmap,
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94 |
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(unsigned long long)input->inode_table, itend - 1);
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95 |
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else if (inside(input->block_bitmap, start, metaend))
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96 |
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ext4_warning(sb, __FUNCTION__,
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97 |
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"Block bitmap (%llu) in GDT table"
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98 |
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" (%llu-%llu)",
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99 |
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(unsigned long long)input->block_bitmap,
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100 |
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start, metaend - 1);
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101 |
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else if (inside(input->inode_bitmap, start, metaend))
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102 |
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ext4_warning(sb, __FUNCTION__,
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103 |
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"Inode bitmap (%llu) in GDT table"
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104 |
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" (%llu-%llu)",
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105 |
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(unsigned long long)input->inode_bitmap,
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start, metaend - 1);
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107 |
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else if (inside(input->inode_table, start, metaend) ||
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108 |
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inside(itend - 1, start, metaend))
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109 |
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ext4_warning(sb, __FUNCTION__,
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110 |
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"Inode table (%llu-%llu) overlaps"
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111 |
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"GDT table (%llu-%llu)",
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112 |
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(unsigned long long)input->inode_table,
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113 |
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itend - 1, start, metaend - 1);
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114 |
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else
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115 |
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err = 0;
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116 |
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brelse(bh);
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117 |
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118 |
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return err;
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119 |
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}
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120 |
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121 |
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static struct buffer_head *bclean(handle_t *handle, struct super_block *sb,
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122 |
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ext4_fsblk_t blk)
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123 |
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{
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124 |
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struct buffer_head *bh;
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125 |
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int err;
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126 |
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127 |
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bh = sb_getblk(sb, blk);
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128 |
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if (!bh)
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129 |
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return ERR_PTR(-EIO);
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130 |
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if ((err = ext4_journal_get_write_access(handle, bh))) {
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131 |
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brelse(bh);
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132 |
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bh = ERR_PTR(err);
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133 |
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} else {
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134 |
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lock_buffer(bh);
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135 |
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memset(bh->b_data, 0, sb->s_blocksize);
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136 |
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set_buffer_uptodate(bh);
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137 |
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unlock_buffer(bh);
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138 |
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}
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139 |
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140 |
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return bh;
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141 |
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}
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142 |
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143 |
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/*
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144 |
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* If we have fewer than thresh credits, extend by EXT4_MAX_TRANS_DATA.
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145 |
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* If that fails, restart the transaction & regain write access for the
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146 |
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* buffer head which is used for block_bitmap modifications.
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147 |
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*/
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148 |
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static int extend_or_restart_transaction(handle_t *handle, int thresh,
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149 |
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struct buffer_head *bh)
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150 |
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{
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151 |
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int err;
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152 |
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153 |
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if (handle->h_buffer_credits >= thresh)
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154 |
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return 0;
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155 |
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156 |
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err = ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA);
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157 |
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if (err < 0)
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158 |
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return err;
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159 |
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if (err) {
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160 |
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if ((err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA)))
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161 |
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return err;
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162 |
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if ((err = ext4_journal_get_write_access(handle, bh)))
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163 |
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return err;
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164 |
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}
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165 |
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166 |
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return 0;
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167 |
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}
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168 |
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169 |
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/*
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170 |
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* Set up the block and inode bitmaps, and the inode table for the new group.
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171 |
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* This doesn't need to be part of the main transaction, since we are only
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172 |
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* changing blocks outside the actual filesystem. We still do journaling to
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173 |
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* ensure the recovery is correct in case of a failure just after resize.
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174 |
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* If any part of this fails, we simply abort the resize.
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175 |
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*/
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176 |
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static int setup_new_group_blocks(struct super_block *sb,
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177 |
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struct ext4_new_group_data *input)
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178 |
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{
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179 |
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struct ext4_sb_info *sbi = EXT4_SB(sb);
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180 |
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ext4_fsblk_t start = ext4_group_first_block_no(sb, input->group);
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181 |
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int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
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182 |
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le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0;
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183 |
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unsigned long gdblocks = ext4_bg_num_gdb(sb, input->group);
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184 |
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struct buffer_head *bh;
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185 |
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handle_t *handle;
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186 |
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ext4_fsblk_t block;
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187 |
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ext4_grpblk_t bit;
|
188 |
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int i;
|
189 |
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int err = 0, err2;
|
190 |
|
|
|
191 |
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/* This transaction may be extended/restarted along the way */
|
192 |
|
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handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
|
193 |
|
|
|
194 |
|
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if (IS_ERR(handle))
|
195 |
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return PTR_ERR(handle);
|
196 |
|
|
|
197 |
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lock_super(sb);
|
198 |
|
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if (input->group != sbi->s_groups_count) {
|
199 |
|
|
err = -EBUSY;
|
200 |
|
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goto exit_journal;
|
201 |
|
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}
|
202 |
|
|
|
203 |
|
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if (IS_ERR(bh = bclean(handle, sb, input->block_bitmap))) {
|
204 |
|
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err = PTR_ERR(bh);
|
205 |
|
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goto exit_journal;
|
206 |
|
|
}
|
207 |
|
|
|
208 |
|
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if (ext4_bg_has_super(sb, input->group)) {
|
209 |
|
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ext4_debug("mark backup superblock %#04lx (+0)\n", start);
|
210 |
|
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ext4_set_bit(0, bh->b_data);
|
211 |
|
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}
|
212 |
|
|
|
213 |
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/* Copy all of the GDT blocks into the backup in this group */
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214 |
|
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for (i = 0, bit = 1, block = start + 1;
|
215 |
|
|
i < gdblocks; i++, block++, bit++) {
|
216 |
|
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struct buffer_head *gdb;
|
217 |
|
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|
218 |
|
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ext4_debug("update backup group %#04lx (+%d)\n", block, bit);
|
219 |
|
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|
220 |
|
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if ((err = extend_or_restart_transaction(handle, 1, bh)))
|
221 |
|
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goto exit_bh;
|
222 |
|
|
|
223 |
|
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gdb = sb_getblk(sb, block);
|
224 |
|
|
if (!gdb) {
|
225 |
|
|
err = -EIO;
|
226 |
|
|
goto exit_bh;
|
227 |
|
|
}
|
228 |
|
|
if ((err = ext4_journal_get_write_access(handle, gdb))) {
|
229 |
|
|
brelse(gdb);
|
230 |
|
|
goto exit_bh;
|
231 |
|
|
}
|
232 |
|
|
lock_buffer(gdb);
|
233 |
|
|
memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, gdb->b_size);
|
234 |
|
|
set_buffer_uptodate(gdb);
|
235 |
|
|
unlock_buffer(gdb);
|
236 |
|
|
ext4_journal_dirty_metadata(handle, gdb);
|
237 |
|
|
ext4_set_bit(bit, bh->b_data);
|
238 |
|
|
brelse(gdb);
|
239 |
|
|
}
|
240 |
|
|
|
241 |
|
|
/* Zero out all of the reserved backup group descriptor table blocks */
|
242 |
|
|
for (i = 0, bit = gdblocks + 1, block = start + bit;
|
243 |
|
|
i < reserved_gdb; i++, block++, bit++) {
|
244 |
|
|
struct buffer_head *gdb;
|
245 |
|
|
|
246 |
|
|
ext4_debug("clear reserved block %#04lx (+%d)\n", block, bit);
|
247 |
|
|
|
248 |
|
|
if ((err = extend_or_restart_transaction(handle, 1, bh)))
|
249 |
|
|
goto exit_bh;
|
250 |
|
|
|
251 |
|
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if (IS_ERR(gdb = bclean(handle, sb, block))) {
|
252 |
|
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err = PTR_ERR(bh);
|
253 |
|
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goto exit_bh;
|
254 |
|
|
}
|
255 |
|
|
ext4_journal_dirty_metadata(handle, gdb);
|
256 |
|
|
ext4_set_bit(bit, bh->b_data);
|
257 |
|
|
brelse(gdb);
|
258 |
|
|
}
|
259 |
|
|
ext4_debug("mark block bitmap %#04x (+%ld)\n", input->block_bitmap,
|
260 |
|
|
input->block_bitmap - start);
|
261 |
|
|
ext4_set_bit(input->block_bitmap - start, bh->b_data);
|
262 |
|
|
ext4_debug("mark inode bitmap %#04x (+%ld)\n", input->inode_bitmap,
|
263 |
|
|
input->inode_bitmap - start);
|
264 |
|
|
ext4_set_bit(input->inode_bitmap - start, bh->b_data);
|
265 |
|
|
|
266 |
|
|
/* Zero out all of the inode table blocks */
|
267 |
|
|
for (i = 0, block = input->inode_table, bit = block - start;
|
268 |
|
|
i < sbi->s_itb_per_group; i++, bit++, block++) {
|
269 |
|
|
struct buffer_head *it;
|
270 |
|
|
|
271 |
|
|
ext4_debug("clear inode block %#04lx (+%d)\n", block, bit);
|
272 |
|
|
|
273 |
|
|
if ((err = extend_or_restart_transaction(handle, 1, bh)))
|
274 |
|
|
goto exit_bh;
|
275 |
|
|
|
276 |
|
|
if (IS_ERR(it = bclean(handle, sb, block))) {
|
277 |
|
|
err = PTR_ERR(it);
|
278 |
|
|
goto exit_bh;
|
279 |
|
|
}
|
280 |
|
|
ext4_journal_dirty_metadata(handle, it);
|
281 |
|
|
brelse(it);
|
282 |
|
|
ext4_set_bit(bit, bh->b_data);
|
283 |
|
|
}
|
284 |
|
|
|
285 |
|
|
if ((err = extend_or_restart_transaction(handle, 2, bh)))
|
286 |
|
|
goto exit_bh;
|
287 |
|
|
|
288 |
|
|
mark_bitmap_end(input->blocks_count, EXT4_BLOCKS_PER_GROUP(sb),
|
289 |
|
|
bh->b_data);
|
290 |
|
|
ext4_journal_dirty_metadata(handle, bh);
|
291 |
|
|
brelse(bh);
|
292 |
|
|
|
293 |
|
|
/* Mark unused entries in inode bitmap used */
|
294 |
|
|
ext4_debug("clear inode bitmap %#04x (+%ld)\n",
|
295 |
|
|
input->inode_bitmap, input->inode_bitmap - start);
|
296 |
|
|
if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) {
|
297 |
|
|
err = PTR_ERR(bh);
|
298 |
|
|
goto exit_journal;
|
299 |
|
|
}
|
300 |
|
|
|
301 |
|
|
mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), EXT4_BLOCKS_PER_GROUP(sb),
|
302 |
|
|
bh->b_data);
|
303 |
|
|
ext4_journal_dirty_metadata(handle, bh);
|
304 |
|
|
exit_bh:
|
305 |
|
|
brelse(bh);
|
306 |
|
|
|
307 |
|
|
exit_journal:
|
308 |
|
|
unlock_super(sb);
|
309 |
|
|
if ((err2 = ext4_journal_stop(handle)) && !err)
|
310 |
|
|
err = err2;
|
311 |
|
|
|
312 |
|
|
return err;
|
313 |
|
|
}
|
314 |
|
|
|
315 |
|
|
/*
|
316 |
|
|
* Iterate through the groups which hold BACKUP superblock/GDT copies in an
|
317 |
|
|
* ext4 filesystem. The counters should be initialized to 1, 5, and 7 before
|
318 |
|
|
* calling this for the first time. In a sparse filesystem it will be the
|
319 |
|
|
* sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
|
320 |
|
|
* For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
|
321 |
|
|
*/
|
322 |
|
|
static unsigned ext4_list_backups(struct super_block *sb, unsigned *three,
|
323 |
|
|
unsigned *five, unsigned *seven)
|
324 |
|
|
{
|
325 |
|
|
unsigned *min = three;
|
326 |
|
|
int mult = 3;
|
327 |
|
|
unsigned ret;
|
328 |
|
|
|
329 |
|
|
if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
330 |
|
|
EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
|
331 |
|
|
ret = *min;
|
332 |
|
|
*min += 1;
|
333 |
|
|
return ret;
|
334 |
|
|
}
|
335 |
|
|
|
336 |
|
|
if (*five < *min) {
|
337 |
|
|
min = five;
|
338 |
|
|
mult = 5;
|
339 |
|
|
}
|
340 |
|
|
if (*seven < *min) {
|
341 |
|
|
min = seven;
|
342 |
|
|
mult = 7;
|
343 |
|
|
}
|
344 |
|
|
|
345 |
|
|
ret = *min;
|
346 |
|
|
*min *= mult;
|
347 |
|
|
|
348 |
|
|
return ret;
|
349 |
|
|
}
|
350 |
|
|
|
351 |
|
|
/*
|
352 |
|
|
* Check that all of the backup GDT blocks are held in the primary GDT block.
|
353 |
|
|
* It is assumed that they are stored in group order. Returns the number of
|
354 |
|
|
* groups in current filesystem that have BACKUPS, or -ve error code.
|
355 |
|
|
*/
|
356 |
|
|
static int verify_reserved_gdb(struct super_block *sb,
|
357 |
|
|
struct buffer_head *primary)
|
358 |
|
|
{
|
359 |
|
|
const ext4_fsblk_t blk = primary->b_blocknr;
|
360 |
|
|
const unsigned long end = EXT4_SB(sb)->s_groups_count;
|
361 |
|
|
unsigned three = 1;
|
362 |
|
|
unsigned five = 5;
|
363 |
|
|
unsigned seven = 7;
|
364 |
|
|
unsigned grp;
|
365 |
|
|
__le32 *p = (__le32 *)primary->b_data;
|
366 |
|
|
int gdbackups = 0;
|
367 |
|
|
|
368 |
|
|
while ((grp = ext4_list_backups(sb, &three, &five, &seven)) < end) {
|
369 |
|
|
if (le32_to_cpu(*p++) !=
|
370 |
|
|
grp * EXT4_BLOCKS_PER_GROUP(sb) + blk){
|
371 |
|
|
ext4_warning(sb, __FUNCTION__,
|
372 |
|
|
"reserved GDT %llu"
|
373 |
|
|
" missing grp %d (%llu)",
|
374 |
|
|
blk, grp,
|
375 |
|
|
grp *
|
376 |
|
|
(ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
|
377 |
|
|
blk);
|
378 |
|
|
return -EINVAL;
|
379 |
|
|
}
|
380 |
|
|
if (++gdbackups > EXT4_ADDR_PER_BLOCK(sb))
|
381 |
|
|
return -EFBIG;
|
382 |
|
|
}
|
383 |
|
|
|
384 |
|
|
return gdbackups;
|
385 |
|
|
}
|
386 |
|
|
|
387 |
|
|
/*
|
388 |
|
|
* Called when we need to bring a reserved group descriptor table block into
|
389 |
|
|
* use from the resize inode. The primary copy of the new GDT block currently
|
390 |
|
|
* is an indirect block (under the double indirect block in the resize inode).
|
391 |
|
|
* The new backup GDT blocks will be stored as leaf blocks in this indirect
|
392 |
|
|
* block, in group order. Even though we know all the block numbers we need,
|
393 |
|
|
* we check to ensure that the resize inode has actually reserved these blocks.
|
394 |
|
|
*
|
395 |
|
|
* Don't need to update the block bitmaps because the blocks are still in use.
|
396 |
|
|
*
|
397 |
|
|
* We get all of the error cases out of the way, so that we are sure to not
|
398 |
|
|
* fail once we start modifying the data on disk, because JBD has no rollback.
|
399 |
|
|
*/
|
400 |
|
|
static int add_new_gdb(handle_t *handle, struct inode *inode,
|
401 |
|
|
struct ext4_new_group_data *input,
|
402 |
|
|
struct buffer_head **primary)
|
403 |
|
|
{
|
404 |
|
|
struct super_block *sb = inode->i_sb;
|
405 |
|
|
struct ext4_super_block *es = EXT4_SB(sb)->s_es;
|
406 |
|
|
unsigned long gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
|
407 |
|
|
ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num;
|
408 |
|
|
struct buffer_head **o_group_desc, **n_group_desc;
|
409 |
|
|
struct buffer_head *dind;
|
410 |
|
|
int gdbackups;
|
411 |
|
|
struct ext4_iloc iloc;
|
412 |
|
|
__le32 *data;
|
413 |
|
|
int err;
|
414 |
|
|
|
415 |
|
|
if (test_opt(sb, DEBUG))
|
416 |
|
|
printk(KERN_DEBUG
|
417 |
|
|
"EXT4-fs: ext4_add_new_gdb: adding group block %lu\n",
|
418 |
|
|
gdb_num);
|
419 |
|
|
|
420 |
|
|
/*
|
421 |
|
|
* If we are not using the primary superblock/GDT copy don't resize,
|
422 |
|
|
* because the user tools have no way of handling this. Probably a
|
423 |
|
|
* bad time to do it anyways.
|
424 |
|
|
*/
|
425 |
|
|
if (EXT4_SB(sb)->s_sbh->b_blocknr !=
|
426 |
|
|
le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) {
|
427 |
|
|
ext4_warning(sb, __FUNCTION__,
|
428 |
|
|
"won't resize using backup superblock at %llu",
|
429 |
|
|
(unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr);
|
430 |
|
|
return -EPERM;
|
431 |
|
|
}
|
432 |
|
|
|
433 |
|
|
*primary = sb_bread(sb, gdblock);
|
434 |
|
|
if (!*primary)
|
435 |
|
|
return -EIO;
|
436 |
|
|
|
437 |
|
|
if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) {
|
438 |
|
|
err = gdbackups;
|
439 |
|
|
goto exit_bh;
|
440 |
|
|
}
|
441 |
|
|
|
442 |
|
|
data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
|
443 |
|
|
dind = sb_bread(sb, le32_to_cpu(*data));
|
444 |
|
|
if (!dind) {
|
445 |
|
|
err = -EIO;
|
446 |
|
|
goto exit_bh;
|
447 |
|
|
}
|
448 |
|
|
|
449 |
|
|
data = (__le32 *)dind->b_data;
|
450 |
|
|
if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) {
|
451 |
|
|
ext4_warning(sb, __FUNCTION__,
|
452 |
|
|
"new group %u GDT block %llu not reserved",
|
453 |
|
|
input->group, gdblock);
|
454 |
|
|
err = -EINVAL;
|
455 |
|
|
goto exit_dind;
|
456 |
|
|
}
|
457 |
|
|
|
458 |
|
|
if ((err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh)))
|
459 |
|
|
goto exit_dind;
|
460 |
|
|
|
461 |
|
|
if ((err = ext4_journal_get_write_access(handle, *primary)))
|
462 |
|
|
goto exit_sbh;
|
463 |
|
|
|
464 |
|
|
if ((err = ext4_journal_get_write_access(handle, dind)))
|
465 |
|
|
goto exit_primary;
|
466 |
|
|
|
467 |
|
|
/* ext4_reserve_inode_write() gets a reference on the iloc */
|
468 |
|
|
if ((err = ext4_reserve_inode_write(handle, inode, &iloc)))
|
469 |
|
|
goto exit_dindj;
|
470 |
|
|
|
471 |
|
|
n_group_desc = kmalloc((gdb_num + 1) * sizeof(struct buffer_head *),
|
472 |
|
|
GFP_KERNEL);
|
473 |
|
|
if (!n_group_desc) {
|
474 |
|
|
err = -ENOMEM;
|
475 |
|
|
ext4_warning (sb, __FUNCTION__,
|
476 |
|
|
"not enough memory for %lu groups", gdb_num + 1);
|
477 |
|
|
goto exit_inode;
|
478 |
|
|
}
|
479 |
|
|
|
480 |
|
|
/*
|
481 |
|
|
* Finally, we have all of the possible failures behind us...
|
482 |
|
|
*
|
483 |
|
|
* Remove new GDT block from inode double-indirect block and clear out
|
484 |
|
|
* the new GDT block for use (which also "frees" the backup GDT blocks
|
485 |
|
|
* from the reserved inode). We don't need to change the bitmaps for
|
486 |
|
|
* these blocks, because they are marked as in-use from being in the
|
487 |
|
|
* reserved inode, and will become GDT blocks (primary and backup).
|
488 |
|
|
*/
|
489 |
|
|
data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)] = 0;
|
490 |
|
|
ext4_journal_dirty_metadata(handle, dind);
|
491 |
|
|
brelse(dind);
|
492 |
|
|
inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9;
|
493 |
|
|
ext4_mark_iloc_dirty(handle, inode, &iloc);
|
494 |
|
|
memset((*primary)->b_data, 0, sb->s_blocksize);
|
495 |
|
|
ext4_journal_dirty_metadata(handle, *primary);
|
496 |
|
|
|
497 |
|
|
o_group_desc = EXT4_SB(sb)->s_group_desc;
|
498 |
|
|
memcpy(n_group_desc, o_group_desc,
|
499 |
|
|
EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
|
500 |
|
|
n_group_desc[gdb_num] = *primary;
|
501 |
|
|
EXT4_SB(sb)->s_group_desc = n_group_desc;
|
502 |
|
|
EXT4_SB(sb)->s_gdb_count++;
|
503 |
|
|
kfree(o_group_desc);
|
504 |
|
|
|
505 |
|
|
es->s_reserved_gdt_blocks =
|
506 |
|
|
cpu_to_le16(le16_to_cpu(es->s_reserved_gdt_blocks) - 1);
|
507 |
|
|
ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
|
508 |
|
|
|
509 |
|
|
return 0;
|
510 |
|
|
|
511 |
|
|
exit_inode:
|
512 |
|
|
//ext4_journal_release_buffer(handle, iloc.bh);
|
513 |
|
|
brelse(iloc.bh);
|
514 |
|
|
exit_dindj:
|
515 |
|
|
//ext4_journal_release_buffer(handle, dind);
|
516 |
|
|
exit_primary:
|
517 |
|
|
//ext4_journal_release_buffer(handle, *primary);
|
518 |
|
|
exit_sbh:
|
519 |
|
|
//ext4_journal_release_buffer(handle, *primary);
|
520 |
|
|
exit_dind:
|
521 |
|
|
brelse(dind);
|
522 |
|
|
exit_bh:
|
523 |
|
|
brelse(*primary);
|
524 |
|
|
|
525 |
|
|
ext4_debug("leaving with error %d\n", err);
|
526 |
|
|
return err;
|
527 |
|
|
}
|
528 |
|
|
|
529 |
|
|
/*
|
530 |
|
|
* Called when we are adding a new group which has a backup copy of each of
|
531 |
|
|
* the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
|
532 |
|
|
* We need to add these reserved backup GDT blocks to the resize inode, so
|
533 |
|
|
* that they are kept for future resizing and not allocated to files.
|
534 |
|
|
*
|
535 |
|
|
* Each reserved backup GDT block will go into a different indirect block.
|
536 |
|
|
* The indirect blocks are actually the primary reserved GDT blocks,
|
537 |
|
|
* so we know in advance what their block numbers are. We only get the
|
538 |
|
|
* double-indirect block to verify it is pointing to the primary reserved
|
539 |
|
|
* GDT blocks so we don't overwrite a data block by accident. The reserved
|
540 |
|
|
* backup GDT blocks are stored in their reserved primary GDT block.
|
541 |
|
|
*/
|
542 |
|
|
static int reserve_backup_gdb(handle_t *handle, struct inode *inode,
|
543 |
|
|
struct ext4_new_group_data *input)
|
544 |
|
|
{
|
545 |
|
|
struct super_block *sb = inode->i_sb;
|
546 |
|
|
int reserved_gdb =le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks);
|
547 |
|
|
struct buffer_head **primary;
|
548 |
|
|
struct buffer_head *dind;
|
549 |
|
|
struct ext4_iloc iloc;
|
550 |
|
|
ext4_fsblk_t blk;
|
551 |
|
|
__le32 *data, *end;
|
552 |
|
|
int gdbackups = 0;
|
553 |
|
|
int res, i;
|
554 |
|
|
int err;
|
555 |
|
|
|
556 |
|
|
primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_KERNEL);
|
557 |
|
|
if (!primary)
|
558 |
|
|
return -ENOMEM;
|
559 |
|
|
|
560 |
|
|
data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
|
561 |
|
|
dind = sb_bread(sb, le32_to_cpu(*data));
|
562 |
|
|
if (!dind) {
|
563 |
|
|
err = -EIO;
|
564 |
|
|
goto exit_free;
|
565 |
|
|
}
|
566 |
|
|
|
567 |
|
|
blk = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + EXT4_SB(sb)->s_gdb_count;
|
568 |
|
|
data = (__le32 *)dind->b_data + EXT4_SB(sb)->s_gdb_count;
|
569 |
|
|
end = (__le32 *)dind->b_data + EXT4_ADDR_PER_BLOCK(sb);
|
570 |
|
|
|
571 |
|
|
/* Get each reserved primary GDT block and verify it holds backups */
|
572 |
|
|
for (res = 0; res < reserved_gdb; res++, blk++) {
|
573 |
|
|
if (le32_to_cpu(*data) != blk) {
|
574 |
|
|
ext4_warning(sb, __FUNCTION__,
|
575 |
|
|
"reserved block %llu"
|
576 |
|
|
" not at offset %ld",
|
577 |
|
|
blk,
|
578 |
|
|
(long)(data - (__le32 *)dind->b_data));
|
579 |
|
|
err = -EINVAL;
|
580 |
|
|
goto exit_bh;
|
581 |
|
|
}
|
582 |
|
|
primary[res] = sb_bread(sb, blk);
|
583 |
|
|
if (!primary[res]) {
|
584 |
|
|
err = -EIO;
|
585 |
|
|
goto exit_bh;
|
586 |
|
|
}
|
587 |
|
|
if ((gdbackups = verify_reserved_gdb(sb, primary[res])) < 0) {
|
588 |
|
|
brelse(primary[res]);
|
589 |
|
|
err = gdbackups;
|
590 |
|
|
goto exit_bh;
|
591 |
|
|
}
|
592 |
|
|
if (++data >= end)
|
593 |
|
|
data = (__le32 *)dind->b_data;
|
594 |
|
|
}
|
595 |
|
|
|
596 |
|
|
for (i = 0; i < reserved_gdb; i++) {
|
597 |
|
|
if ((err = ext4_journal_get_write_access(handle, primary[i]))) {
|
598 |
|
|
/*
|
599 |
|
|
int j;
|
600 |
|
|
for (j = 0; j < i; j++)
|
601 |
|
|
ext4_journal_release_buffer(handle, primary[j]);
|
602 |
|
|
*/
|
603 |
|
|
goto exit_bh;
|
604 |
|
|
}
|
605 |
|
|
}
|
606 |
|
|
|
607 |
|
|
if ((err = ext4_reserve_inode_write(handle, inode, &iloc)))
|
608 |
|
|
goto exit_bh;
|
609 |
|
|
|
610 |
|
|
/*
|
611 |
|
|
* Finally we can add each of the reserved backup GDT blocks from
|
612 |
|
|
* the new group to its reserved primary GDT block.
|
613 |
|
|
*/
|
614 |
|
|
blk = input->group * EXT4_BLOCKS_PER_GROUP(sb);
|
615 |
|
|
for (i = 0; i < reserved_gdb; i++) {
|
616 |
|
|
int err2;
|
617 |
|
|
data = (__le32 *)primary[i]->b_data;
|
618 |
|
|
/* printk("reserving backup %lu[%u] = %lu\n",
|
619 |
|
|
primary[i]->b_blocknr, gdbackups,
|
620 |
|
|
blk + primary[i]->b_blocknr); */
|
621 |
|
|
data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr);
|
622 |
|
|
err2 = ext4_journal_dirty_metadata(handle, primary[i]);
|
623 |
|
|
if (!err)
|
624 |
|
|
err = err2;
|
625 |
|
|
}
|
626 |
|
|
inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9;
|
627 |
|
|
ext4_mark_iloc_dirty(handle, inode, &iloc);
|
628 |
|
|
|
629 |
|
|
exit_bh:
|
630 |
|
|
while (--res >= 0)
|
631 |
|
|
brelse(primary[res]);
|
632 |
|
|
brelse(dind);
|
633 |
|
|
|
634 |
|
|
exit_free:
|
635 |
|
|
kfree(primary);
|
636 |
|
|
|
637 |
|
|
return err;
|
638 |
|
|
}
|
639 |
|
|
|
640 |
|
|
/*
|
641 |
|
|
* Update the backup copies of the ext4 metadata. These don't need to be part
|
642 |
|
|
* of the main resize transaction, because e2fsck will re-write them if there
|
643 |
|
|
* is a problem (basically only OOM will cause a problem). However, we
|
644 |
|
|
* _should_ update the backups if possible, in case the primary gets trashed
|
645 |
|
|
* for some reason and we need to run e2fsck from a backup superblock. The
|
646 |
|
|
* important part is that the new block and inode counts are in the backup
|
647 |
|
|
* superblocks, and the location of the new group metadata in the GDT backups.
|
648 |
|
|
*
|
649 |
|
|
* We do not need lock_super() for this, because these blocks are not
|
650 |
|
|
* otherwise touched by the filesystem code when it is mounted. We don't
|
651 |
|
|
* need to worry about last changing from sbi->s_groups_count, because the
|
652 |
|
|
* worst that can happen is that we do not copy the full number of backups
|
653 |
|
|
* at this time. The resize which changed s_groups_count will backup again.
|
654 |
|
|
*/
|
655 |
|
|
static void update_backups(struct super_block *sb,
|
656 |
|
|
int blk_off, char *data, int size)
|
657 |
|
|
{
|
658 |
|
|
struct ext4_sb_info *sbi = EXT4_SB(sb);
|
659 |
|
|
const unsigned long last = sbi->s_groups_count;
|
660 |
|
|
const int bpg = EXT4_BLOCKS_PER_GROUP(sb);
|
661 |
|
|
unsigned three = 1;
|
662 |
|
|
unsigned five = 5;
|
663 |
|
|
unsigned seven = 7;
|
664 |
|
|
unsigned group;
|
665 |
|
|
int rest = sb->s_blocksize - size;
|
666 |
|
|
handle_t *handle;
|
667 |
|
|
int err = 0, err2;
|
668 |
|
|
|
669 |
|
|
handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
|
670 |
|
|
if (IS_ERR(handle)) {
|
671 |
|
|
group = 1;
|
672 |
|
|
err = PTR_ERR(handle);
|
673 |
|
|
goto exit_err;
|
674 |
|
|
}
|
675 |
|
|
|
676 |
|
|
while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) {
|
677 |
|
|
struct buffer_head *bh;
|
678 |
|
|
|
679 |
|
|
/* Out of journal space, and can't get more - abort - so sad */
|
680 |
|
|
if (handle->h_buffer_credits == 0 &&
|
681 |
|
|
ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA) &&
|
682 |
|
|
(err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA)))
|
683 |
|
|
break;
|
684 |
|
|
|
685 |
|
|
bh = sb_getblk(sb, group * bpg + blk_off);
|
686 |
|
|
if (!bh) {
|
687 |
|
|
err = -EIO;
|
688 |
|
|
break;
|
689 |
|
|
}
|
690 |
|
|
ext4_debug("update metadata backup %#04lx\n",
|
691 |
|
|
(unsigned long)bh->b_blocknr);
|
692 |
|
|
if ((err = ext4_journal_get_write_access(handle, bh)))
|
693 |
|
|
break;
|
694 |
|
|
lock_buffer(bh);
|
695 |
|
|
memcpy(bh->b_data, data, size);
|
696 |
|
|
if (rest)
|
697 |
|
|
memset(bh->b_data + size, 0, rest);
|
698 |
|
|
set_buffer_uptodate(bh);
|
699 |
|
|
unlock_buffer(bh);
|
700 |
|
|
ext4_journal_dirty_metadata(handle, bh);
|
701 |
|
|
brelse(bh);
|
702 |
|
|
}
|
703 |
|
|
if ((err2 = ext4_journal_stop(handle)) && !err)
|
704 |
|
|
err = err2;
|
705 |
|
|
|
706 |
|
|
/*
|
707 |
|
|
* Ugh! Need to have e2fsck write the backup copies. It is too
|
708 |
|
|
* late to revert the resize, we shouldn't fail just because of
|
709 |
|
|
* the backup copies (they are only needed in case of corruption).
|
710 |
|
|
*
|
711 |
|
|
* However, if we got here we have a journal problem too, so we
|
712 |
|
|
* can't really start a transaction to mark the superblock.
|
713 |
|
|
* Chicken out and just set the flag on the hope it will be written
|
714 |
|
|
* to disk, and if not - we will simply wait until next fsck.
|
715 |
|
|
*/
|
716 |
|
|
exit_err:
|
717 |
|
|
if (err) {
|
718 |
|
|
ext4_warning(sb, __FUNCTION__,
|
719 |
|
|
"can't update backup for group %d (err %d), "
|
720 |
|
|
"forcing fsck on next reboot", group, err);
|
721 |
|
|
sbi->s_mount_state &= ~EXT4_VALID_FS;
|
722 |
|
|
sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
|
723 |
|
|
mark_buffer_dirty(sbi->s_sbh);
|
724 |
|
|
}
|
725 |
|
|
}
|
726 |
|
|
|
727 |
|
|
/* Add group descriptor data to an existing or new group descriptor block.
|
728 |
|
|
* Ensure we handle all possible error conditions _before_ we start modifying
|
729 |
|
|
* the filesystem, because we cannot abort the transaction and not have it
|
730 |
|
|
* write the data to disk.
|
731 |
|
|
*
|
732 |
|
|
* If we are on a GDT block boundary, we need to get the reserved GDT block.
|
733 |
|
|
* Otherwise, we may need to add backup GDT blocks for a sparse group.
|
734 |
|
|
*
|
735 |
|
|
* We only need to hold the superblock lock while we are actually adding
|
736 |
|
|
* in the new group's counts to the superblock. Prior to that we have
|
737 |
|
|
* not really "added" the group at all. We re-check that we are still
|
738 |
|
|
* adding in the last group in case things have changed since verifying.
|
739 |
|
|
*/
|
740 |
|
|
int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
|
741 |
|
|
{
|
742 |
|
|
struct ext4_sb_info *sbi = EXT4_SB(sb);
|
743 |
|
|
struct ext4_super_block *es = sbi->s_es;
|
744 |
|
|
int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
|
745 |
|
|
le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
|
746 |
|
|
struct buffer_head *primary = NULL;
|
747 |
|
|
struct ext4_group_desc *gdp;
|
748 |
|
|
struct inode *inode = NULL;
|
749 |
|
|
handle_t *handle;
|
750 |
|
|
int gdb_off, gdb_num;
|
751 |
|
|
int err, err2;
|
752 |
|
|
|
753 |
|
|
gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
|
754 |
|
|
gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb);
|
755 |
|
|
|
756 |
|
|
if (gdb_off == 0 && !EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
757 |
|
|
EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
|
758 |
|
|
ext4_warning(sb, __FUNCTION__,
|
759 |
|
|
"Can't resize non-sparse filesystem further");
|
760 |
|
|
return -EPERM;
|
761 |
|
|
}
|
762 |
|
|
|
763 |
|
|
if (ext4_blocks_count(es) + input->blocks_count <
|
764 |
|
|
ext4_blocks_count(es)) {
|
765 |
|
|
ext4_warning(sb, __FUNCTION__, "blocks_count overflow\n");
|
766 |
|
|
return -EINVAL;
|
767 |
|
|
}
|
768 |
|
|
|
769 |
|
|
if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) <
|
770 |
|
|
le32_to_cpu(es->s_inodes_count)) {
|
771 |
|
|
ext4_warning(sb, __FUNCTION__, "inodes_count overflow\n");
|
772 |
|
|
return -EINVAL;
|
773 |
|
|
}
|
774 |
|
|
|
775 |
|
|
if (reserved_gdb || gdb_off == 0) {
|
776 |
|
|
if (!EXT4_HAS_COMPAT_FEATURE(sb,
|
777 |
|
|
EXT4_FEATURE_COMPAT_RESIZE_INODE)){
|
778 |
|
|
ext4_warning(sb, __FUNCTION__,
|
779 |
|
|
"No reserved GDT blocks, can't resize");
|
780 |
|
|
return -EPERM;
|
781 |
|
|
}
|
782 |
|
|
inode = iget(sb, EXT4_RESIZE_INO);
|
783 |
|
|
if (!inode || is_bad_inode(inode)) {
|
784 |
|
|
ext4_warning(sb, __FUNCTION__,
|
785 |
|
|
"Error opening resize inode");
|
786 |
|
|
iput(inode);
|
787 |
|
|
return -ENOENT;
|
788 |
|
|
}
|
789 |
|
|
}
|
790 |
|
|
|
791 |
|
|
if ((err = verify_group_input(sb, input)))
|
792 |
|
|
goto exit_put;
|
793 |
|
|
|
794 |
|
|
if ((err = setup_new_group_blocks(sb, input)))
|
795 |
|
|
goto exit_put;
|
796 |
|
|
|
797 |
|
|
/*
|
798 |
|
|
* We will always be modifying at least the superblock and a GDT
|
799 |
|
|
* block. If we are adding a group past the last current GDT block,
|
800 |
|
|
* we will also modify the inode and the dindirect block. If we
|
801 |
|
|
* are adding a group with superblock/GDT backups we will also
|
802 |
|
|
* modify each of the reserved GDT dindirect blocks.
|
803 |
|
|
*/
|
804 |
|
|
handle = ext4_journal_start_sb(sb,
|
805 |
|
|
ext4_bg_has_super(sb, input->group) ?
|
806 |
|
|
3 + reserved_gdb : 4);
|
807 |
|
|
if (IS_ERR(handle)) {
|
808 |
|
|
err = PTR_ERR(handle);
|
809 |
|
|
goto exit_put;
|
810 |
|
|
}
|
811 |
|
|
|
812 |
|
|
lock_super(sb);
|
813 |
|
|
if (input->group != sbi->s_groups_count) {
|
814 |
|
|
ext4_warning(sb, __FUNCTION__,
|
815 |
|
|
"multiple resizers run on filesystem!");
|
816 |
|
|
err = -EBUSY;
|
817 |
|
|
goto exit_journal;
|
818 |
|
|
}
|
819 |
|
|
|
820 |
|
|
if ((err = ext4_journal_get_write_access(handle, sbi->s_sbh)))
|
821 |
|
|
goto exit_journal;
|
822 |
|
|
|
823 |
|
|
/*
|
824 |
|
|
* We will only either add reserved group blocks to a backup group
|
825 |
|
|
* or remove reserved blocks for the first group in a new group block.
|
826 |
|
|
* Doing both would be mean more complex code, and sane people don't
|
827 |
|
|
* use non-sparse filesystems anymore. This is already checked above.
|
828 |
|
|
*/
|
829 |
|
|
if (gdb_off) {
|
830 |
|
|
primary = sbi->s_group_desc[gdb_num];
|
831 |
|
|
if ((err = ext4_journal_get_write_access(handle, primary)))
|
832 |
|
|
goto exit_journal;
|
833 |
|
|
|
834 |
|
|
if (reserved_gdb && ext4_bg_num_gdb(sb, input->group) &&
|
835 |
|
|
(err = reserve_backup_gdb(handle, inode, input)))
|
836 |
|
|
goto exit_journal;
|
837 |
|
|
} else if ((err = add_new_gdb(handle, inode, input, &primary)))
|
838 |
|
|
goto exit_journal;
|
839 |
|
|
|
840 |
|
|
/*
|
841 |
|
|
* OK, now we've set up the new group. Time to make it active.
|
842 |
|
|
*
|
843 |
|
|
* Current kernels don't lock all allocations via lock_super(),
|
844 |
|
|
* so we have to be safe wrt. concurrent accesses the group
|
845 |
|
|
* data. So we need to be careful to set all of the relevant
|
846 |
|
|
* group descriptor data etc. *before* we enable the group.
|
847 |
|
|
*
|
848 |
|
|
* The key field here is sbi->s_groups_count: as long as
|
849 |
|
|
* that retains its old value, nobody is going to access the new
|
850 |
|
|
* group.
|
851 |
|
|
*
|
852 |
|
|
* So first we update all the descriptor metadata for the new
|
853 |
|
|
* group; then we update the total disk blocks count; then we
|
854 |
|
|
* update the groups count to enable the group; then finally we
|
855 |
|
|
* update the free space counts so that the system can start
|
856 |
|
|
* using the new disk blocks.
|
857 |
|
|
*/
|
858 |
|
|
|
859 |
|
|
/* Update group descriptor block for new group */
|
860 |
|
|
gdp = (struct ext4_group_desc *)primary->b_data + gdb_off;
|
861 |
|
|
|
862 |
|
|
ext4_block_bitmap_set(sb, gdp, input->block_bitmap); /* LV FIXME */
|
863 |
|
|
ext4_inode_bitmap_set(sb, gdp, input->inode_bitmap); /* LV FIXME */
|
864 |
|
|
ext4_inode_table_set(sb, gdp, input->inode_table); /* LV FIXME */
|
865 |
|
|
gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
|
866 |
|
|
gdp->bg_free_inodes_count = cpu_to_le16(EXT4_INODES_PER_GROUP(sb));
|
867 |
|
|
gdp->bg_checksum = ext4_group_desc_csum(sbi, input->group, gdp);
|
868 |
|
|
|
869 |
|
|
/*
|
870 |
|
|
* Make the new blocks and inodes valid next. We do this before
|
871 |
|
|
* increasing the group count so that once the group is enabled,
|
872 |
|
|
* all of its blocks and inodes are already valid.
|
873 |
|
|
*
|
874 |
|
|
* We always allocate group-by-group, then block-by-block or
|
875 |
|
|
* inode-by-inode within a group, so enabling these
|
876 |
|
|
* blocks/inodes before the group is live won't actually let us
|
877 |
|
|
* allocate the new space yet.
|
878 |
|
|
*/
|
879 |
|
|
ext4_blocks_count_set(es, ext4_blocks_count(es) +
|
880 |
|
|
input->blocks_count);
|
881 |
|
|
es->s_inodes_count = cpu_to_le32(le32_to_cpu(es->s_inodes_count) +
|
882 |
|
|
EXT4_INODES_PER_GROUP(sb));
|
883 |
|
|
|
884 |
|
|
/*
|
885 |
|
|
* We need to protect s_groups_count against other CPUs seeing
|
886 |
|
|
* inconsistent state in the superblock.
|
887 |
|
|
*
|
888 |
|
|
* The precise rules we use are:
|
889 |
|
|
*
|
890 |
|
|
* * Writers of s_groups_count *must* hold lock_super
|
891 |
|
|
* AND
|
892 |
|
|
* * Writers must perform a smp_wmb() after updating all dependent
|
893 |
|
|
* data and before modifying the groups count
|
894 |
|
|
*
|
895 |
|
|
* * Readers must hold lock_super() over the access
|
896 |
|
|
* OR
|
897 |
|
|
* * Readers must perform an smp_rmb() after reading the groups count
|
898 |
|
|
* and before reading any dependent data.
|
899 |
|
|
*
|
900 |
|
|
* NB. These rules can be relaxed when checking the group count
|
901 |
|
|
* while freeing data, as we can only allocate from a block
|
902 |
|
|
* group after serialising against the group count, and we can
|
903 |
|
|
* only then free after serialising in turn against that
|
904 |
|
|
* allocation.
|
905 |
|
|
*/
|
906 |
|
|
smp_wmb();
|
907 |
|
|
|
908 |
|
|
/* Update the global fs size fields */
|
909 |
|
|
sbi->s_groups_count++;
|
910 |
|
|
|
911 |
|
|
ext4_journal_dirty_metadata(handle, primary);
|
912 |
|
|
|
913 |
|
|
/* Update the reserved block counts only once the new group is
|
914 |
|
|
* active. */
|
915 |
|
|
ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) +
|
916 |
|
|
input->reserved_blocks);
|
917 |
|
|
|
918 |
|
|
/* Update the free space counts */
|
919 |
|
|
percpu_counter_add(&sbi->s_freeblocks_counter,
|
920 |
|
|
input->free_blocks_count);
|
921 |
|
|
percpu_counter_add(&sbi->s_freeinodes_counter,
|
922 |
|
|
EXT4_INODES_PER_GROUP(sb));
|
923 |
|
|
|
924 |
|
|
ext4_journal_dirty_metadata(handle, sbi->s_sbh);
|
925 |
|
|
sb->s_dirt = 1;
|
926 |
|
|
|
927 |
|
|
exit_journal:
|
928 |
|
|
unlock_super(sb);
|
929 |
|
|
if ((err2 = ext4_journal_stop(handle)) && !err)
|
930 |
|
|
err = err2;
|
931 |
|
|
if (!err) {
|
932 |
|
|
update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
|
933 |
|
|
sizeof(struct ext4_super_block));
|
934 |
|
|
update_backups(sb, primary->b_blocknr, primary->b_data,
|
935 |
|
|
primary->b_size);
|
936 |
|
|
}
|
937 |
|
|
exit_put:
|
938 |
|
|
iput(inode);
|
939 |
|
|
return err;
|
940 |
|
|
} /* ext4_group_add */
|
941 |
|
|
|
942 |
|
|
/* Extend the filesystem to the new number of blocks specified. This entry
|
943 |
|
|
* point is only used to extend the current filesystem to the end of the last
|
944 |
|
|
* existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
|
945 |
|
|
* for emergencies (because it has no dependencies on reserved blocks).
|
946 |
|
|
*
|
947 |
|
|
* If we _really_ wanted, we could use default values to call ext4_group_add()
|
948 |
|
|
* allow the "remount" trick to work for arbitrary resizing, assuming enough
|
949 |
|
|
* GDT blocks are reserved to grow to the desired size.
|
950 |
|
|
*/
|
951 |
|
|
int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
|
952 |
|
|
ext4_fsblk_t n_blocks_count)
|
953 |
|
|
{
|
954 |
|
|
ext4_fsblk_t o_blocks_count;
|
955 |
|
|
unsigned long o_groups_count;
|
956 |
|
|
ext4_grpblk_t last;
|
957 |
|
|
ext4_grpblk_t add;
|
958 |
|
|
struct buffer_head * bh;
|
959 |
|
|
handle_t *handle;
|
960 |
|
|
int err;
|
961 |
|
|
unsigned long freed_blocks;
|
962 |
|
|
|
963 |
|
|
/* We don't need to worry about locking wrt other resizers just
|
964 |
|
|
* yet: we're going to revalidate es->s_blocks_count after
|
965 |
|
|
* taking lock_super() below. */
|
966 |
|
|
o_blocks_count = ext4_blocks_count(es);
|
967 |
|
|
o_groups_count = EXT4_SB(sb)->s_groups_count;
|
968 |
|
|
|
969 |
|
|
if (test_opt(sb, DEBUG))
|
970 |
|
|
printk(KERN_DEBUG "EXT4-fs: extending last group from %llu uto %llu blocks\n",
|
971 |
|
|
o_blocks_count, n_blocks_count);
|
972 |
|
|
|
973 |
|
|
if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
|
974 |
|
|
return 0;
|
975 |
|
|
|
976 |
|
|
if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
|
977 |
|
|
printk(KERN_ERR "EXT4-fs: filesystem on %s:"
|
978 |
|
|
" too large to resize to %llu blocks safely\n",
|
979 |
|
|
sb->s_id, n_blocks_count);
|
980 |
|
|
if (sizeof(sector_t) < 8)
|
981 |
|
|
ext4_warning(sb, __FUNCTION__,
|
982 |
|
|
"CONFIG_LBD not enabled\n");
|
983 |
|
|
return -EINVAL;
|
984 |
|
|
}
|
985 |
|
|
|
986 |
|
|
if (n_blocks_count < o_blocks_count) {
|
987 |
|
|
ext4_warning(sb, __FUNCTION__,
|
988 |
|
|
"can't shrink FS - resize aborted");
|
989 |
|
|
return -EBUSY;
|
990 |
|
|
}
|
991 |
|
|
|
992 |
|
|
/* Handle the remaining blocks in the last group only. */
|
993 |
|
|
ext4_get_group_no_and_offset(sb, o_blocks_count, NULL, &last);
|
994 |
|
|
|
995 |
|
|
if (last == 0) {
|
996 |
|
|
ext4_warning(sb, __FUNCTION__,
|
997 |
|
|
"need to use ext2online to resize further");
|
998 |
|
|
return -EPERM;
|
999 |
|
|
}
|
1000 |
|
|
|
1001 |
|
|
add = EXT4_BLOCKS_PER_GROUP(sb) - last;
|
1002 |
|
|
|
1003 |
|
|
if (o_blocks_count + add < o_blocks_count) {
|
1004 |
|
|
ext4_warning(sb, __FUNCTION__, "blocks_count overflow");
|
1005 |
|
|
return -EINVAL;
|
1006 |
|
|
}
|
1007 |
|
|
|
1008 |
|
|
if (o_blocks_count + add > n_blocks_count)
|
1009 |
|
|
add = n_blocks_count - o_blocks_count;
|
1010 |
|
|
|
1011 |
|
|
if (o_blocks_count + add < n_blocks_count)
|
1012 |
|
|
ext4_warning(sb, __FUNCTION__,
|
1013 |
|
|
"will only finish group (%llu"
|
1014 |
|
|
" blocks, %u new)",
|
1015 |
|
|
o_blocks_count + add, add);
|
1016 |
|
|
|
1017 |
|
|
/* See if the device is actually as big as what was requested */
|
1018 |
|
|
bh = sb_bread(sb, o_blocks_count + add -1);
|
1019 |
|
|
if (!bh) {
|
1020 |
|
|
ext4_warning(sb, __FUNCTION__,
|
1021 |
|
|
"can't read last block, resize aborted");
|
1022 |
|
|
return -ENOSPC;
|
1023 |
|
|
}
|
1024 |
|
|
brelse(bh);
|
1025 |
|
|
|
1026 |
|
|
/* We will update the superblock, one block bitmap, and
|
1027 |
|
|
* one group descriptor via ext4_free_blocks().
|
1028 |
|
|
*/
|
1029 |
|
|
handle = ext4_journal_start_sb(sb, 3);
|
1030 |
|
|
if (IS_ERR(handle)) {
|
1031 |
|
|
err = PTR_ERR(handle);
|
1032 |
|
|
ext4_warning(sb, __FUNCTION__, "error %d on journal start",err);
|
1033 |
|
|
goto exit_put;
|
1034 |
|
|
}
|
1035 |
|
|
|
1036 |
|
|
lock_super(sb);
|
1037 |
|
|
if (o_blocks_count != ext4_blocks_count(es)) {
|
1038 |
|
|
ext4_warning(sb, __FUNCTION__,
|
1039 |
|
|
"multiple resizers run on filesystem!");
|
1040 |
|
|
unlock_super(sb);
|
1041 |
|
|
err = -EBUSY;
|
1042 |
|
|
goto exit_put;
|
1043 |
|
|
}
|
1044 |
|
|
|
1045 |
|
|
if ((err = ext4_journal_get_write_access(handle,
|
1046 |
|
|
EXT4_SB(sb)->s_sbh))) {
|
1047 |
|
|
ext4_warning(sb, __FUNCTION__,
|
1048 |
|
|
"error %d on journal write access", err);
|
1049 |
|
|
unlock_super(sb);
|
1050 |
|
|
ext4_journal_stop(handle);
|
1051 |
|
|
goto exit_put;
|
1052 |
|
|
}
|
1053 |
|
|
ext4_blocks_count_set(es, o_blocks_count + add);
|
1054 |
|
|
ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
|
1055 |
|
|
sb->s_dirt = 1;
|
1056 |
|
|
unlock_super(sb);
|
1057 |
|
|
ext4_debug("freeing blocks %lu through %llu\n", o_blocks_count,
|
1058 |
|
|
o_blocks_count + add);
|
1059 |
|
|
ext4_free_blocks_sb(handle, sb, o_blocks_count, add, &freed_blocks);
|
1060 |
|
|
ext4_debug("freed blocks %llu through %llu\n", o_blocks_count,
|
1061 |
|
|
o_blocks_count + add);
|
1062 |
|
|
if ((err = ext4_journal_stop(handle)))
|
1063 |
|
|
goto exit_put;
|
1064 |
|
|
if (test_opt(sb, DEBUG))
|
1065 |
|
|
printk(KERN_DEBUG "EXT4-fs: extended group to %llu blocks\n",
|
1066 |
|
|
ext4_blocks_count(es));
|
1067 |
|
|
update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es,
|
1068 |
|
|
sizeof(struct ext4_super_block));
|
1069 |
|
|
exit_put:
|
1070 |
|
|
return err;
|
1071 |
|
|
} /* ext4_group_extend */
|