ldiskfs/kernel_patches/patches/ext4-mballoc-extra-checks-sles11.patch

   1 Index: linux-2.6.27.21-0.1/fs/ext4/mballoc.c
   2 ===================================================================
   3 --- linux-2.6.27.21-0.1.orig/fs/ext4/mballoc.c
   4 +++ linux-2.6.27.21-0.1/fs/ext4/mballoc.c
   5 @@ -333,7 +333,7 @@
   6  static struct kmem_cache *ext4_pspace_cachep;
   7  static struct kmem_cache *ext4_ac_cachep;
   8  static struct kmem_cache *ext4_free_ext_cachep;
   9 -static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
  10 +static int ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
  11                                         ext4_group_t group);
  12  static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
  13                                                 ext4_group_t group);
  14 @@ -672,7 +672,7 @@ static void ext4_mb_mark_free_simple(str
  15  }
  16
  17  static noinline_for_stack
  18 -void ext4_mb_generate_buddy(struct super_block *sb,
  19 +int ext4_mb_generate_buddy(struct super_block *sb,
  20                                 void *buddy, void *bitmap, ext4_group_t group)
  21  {
  22         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
  23 @@ -704,14 +704,13 @@ static void ext4_mb_generate_buddy(struc
  24         grp->bb_fragments = fragments;
  25
  26         if (free != grp->bb_free) {
  27 -               ext4_grp_locked_error(sb, group,  __func__,
  28 -                       "EXT4-fs: group %u: %u blocks in bitmap, %u in gd",
  29 -                       group, free, grp->bb_free);
  30 -               /*
  31 -                * If we intent to continue, we consider group descritor
  32 -                * corrupt and update bb_free using bitmap value
  33 -                */
  34 -               grp->bb_free = free;
  35 +               struct ext4_group_desc *gdp;
  36 +               gdp = ext4_get_group_desc (sb, group, NULL);
  37 +               ext4_grp_locked_error(sb, group, __func__,
  38 +                       "group %u: %u blocks in bitmap, %u in bb, "
  39 +                       "%u in gd\n", group, free, grp->bb_free,
  40 +                       ext4_free_blks_count(sb, gdp));
  41 +               return -EIO;
  42         }
  43
  44         clear_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state));
  45 @@ -721,6 +720,8 @@ static void ext4_mb_generate_buddy(struc
  46         EXT4_SB(sb)->s_mb_buddies_generated++;
  47         EXT4_SB(sb)->s_mb_generation_time += period;
  48         spin_unlock(&EXT4_SB(sb)->s_bal_lock);
  49 +
  50 +       return 0;
  51  }
  52
  53  /* The buddy information is attached the buddy cache inode
  54 @@ -850,7 +851,7 @@ static int ext4_mb_init_cache(struct pag
  55         first_block = page->index * blocks_per_page;
  56         /* init the page  */
  57         memset(page_address(page), 0xff, PAGE_CACHE_SIZE);
  58 -       for (i = 0; i < blocks_per_page; i++) {
  59 +       for (i = 0; i < blocks_per_page && err == 0; i++) {
  60                 int group;
  61                 struct ext4_group_info *grinfo;
  62
  63 @@ -884,7 +885,7 @@ static int ext4_mb_init_cache(struct pag
  64                          * incore got set to the group block bitmap below
  65                          */
  66                         ext4_lock_group(sb, group);
  67 -                       ext4_mb_generate_buddy(sb, data, incore, group);
  68 +                       err = ext4_mb_generate_buddy(sb, data, incore, group);
  69                         ext4_unlock_group(sb, group);
  70                         incore = NULL;
  71                 } else {
  72 @@ -898,7 +899,7 @@ static int ext4_mb_init_cache(struct pag
  73                         memcpy(data, bitmap, blocksize);
  74
  75                         /* mark all preallocated blks used in in-core bitmap */
  76 -                       ext4_mb_generate_from_pa(sb, data, group);
  77 +                       err = ext4_mb_generate_from_pa(sb, data, group);
  78                         ext4_mb_generate_from_freelist(sb, data, group);
  79                         ext4_unlock_group(sb, group);
  80
  81 @@ -908,6 +909,7 @@ static int ext4_mb_init_cache(struct pag
  82                         incore = data;
  83                 }
  84         }
  85 +       if (likely(err == 0))
  86         SetPageUptodate(page);
  87
  88  out:
  89 @@ -2345,9 +2350,11 @@ static void *ext4_mb_seq_groups_next(str
  90  static int ext4_mb_seq_groups_show(struct seq_file *seq, void *v)
  91  {
  92         struct super_block *sb = seq->private;
  93 +       struct ext4_group_desc *gdp;
  94         ext4_group_t group = (ext4_group_t) ((unsigned long) v);
  95         int i;
  96         int err;
  97 +       unsigned free = 0;
  98         struct ext4_buddy e4b;
  99         struct sg {
 100                 struct ext4_group_info info;
 101 @@ -2356,10 +2363,10 @@ static int ext4_mb_seq_groups_show(struc
 102
 103         group--;
 104         if (group == 0)
 105 -               seq_printf(seq, "#%-5s: %-5s %-5s %-5s "
 106 +               seq_printf(seq, "#%-5s: %-5s %-5s %-5s %-5s %-5s"
 107                                 "[ %-5s %-5s %-5s %-5s %-5s %-5s %-5s "
 108                                   "%-5s %-5s %-5s %-5s %-5s %-5s %-5s ]\n",
 109 -                          "group", "free", "frags", "first",
 110 +                          "group", "free", "frags", "first", "first", "pa",
 111                            "2^0", "2^1", "2^2", "2^3", "2^4", "2^5", "2^6",
 112                            "2^7", "2^8", "2^9", "2^10", "2^11", "2^12", "2^13");
 113
 114 @@ -2371,12 +2378,18 @@ static int ext4_mb_seq_groups_show(struc
 115                 seq_printf(seq, "#%-5u: I/O error\n", group);
 116                 return 0;
 117         }
 118 +
 119 +       gdp = ext4_get_group_desc(sb, group, NULL);
 120 +       if (gdp != NULL)
 121 +               free = ext4_free_blks_count(sb, gdp);
 122 +
 123         ext4_lock_group(sb, group);
 124         memcpy(&sg, ext4_get_group_info(sb, group), i);
 125         ext4_unlock_group(sb, group);
 126         ext4_mb_unload_buddy(&e4b);
 127
 128 -       seq_printf(seq, "#%-5u: %-5u %-5u %-5u [", group, sg.info.bb_free,
 129 +       seq_printf(seq, "#%-5u: %-5u %-5u %-5u %-5u [", group,
 130 +                       sg.info.bb_free, free,
 131                         sg.info.bb_fragments, sg.info.bb_first_free);
 132         for (i = 0; i <= 13; i++)
 133                 seq_printf(seq, " %-5u", i <= sb->s_blocksize_bits + 1 ?
 134 @@ -3695,23 +3709,68 @@ static void ext4_mb_generate_from_freeli
 135  }
 136
 137  /*
 138 + * check free blocks in bitmap match free block in group descriptor
 139 + * do this before taking preallocated blocks into account to be able
 140 + * to detect on-disk corruptions. The group lock should be hold by the
 141 + * caller.
 142 + */
 143 +int ext4_mb_check_ondisk_bitmap(struct super_block *sb, void *bitmap,
 144 +                               struct ext4_group_desc *gdp, int group)
 145 +{
 146 +       unsigned short max = EXT4_BLOCKS_PER_GROUP(sb);
 147 +       unsigned short i, first, free = 0;
 148 +
 149 +       i = mb_find_next_zero_bit(bitmap, max, 0);
 150 +
 151 +       while (i < max) {
 152 +               first = i;
 153 +               i = mb_find_next_bit(bitmap, max, i);
 154 +               if (i > max)
 155 +                       i = max;
 156 +               free += i - first;
 157 +               if (i < max)
 158 +                       i = mb_find_next_zero_bit(bitmap, max, i);
 159 +       }
 160 +
 161 +       if (free != ext4_free_blks_count(sb, gdp)) {
 162 +               ext4_error(sb, __FUNCTION__, "on-disk bitmap for group %d"
 163 +                       "corrupted: %u blocks free in bitmap, %u - in gd\n",
 164 +                       group, free, ext4_free_blks_count(sb, gdp));
 165 +               return -EIO;
 166 +       }
 167 +       return 0;
 168 +}
 169 +
 170 +/*
 171   * the function goes through all preallocation in this group and marks them
 172   * used in in-core bitmap. buddy must be generated from this bitmap
 173   * Need to be called with ext4 group lock held
 174   */
 175  static noinline_for_stack
 176 -void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
 177 +int ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
 178                                         ext4_group_t group)
 179  {
 180         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 181         struct ext4_prealloc_space *pa;
 182 +       struct ext4_group_desc *gdp;
 183         struct list_head *cur;
 184         ext4_group_t groupnr;
 185         ext4_grpblk_t start;
 186         int preallocated = 0;
 187         int count = 0;
 188 +       int skip = 0;
 189 +       int err;
 190         int len;
 191
 192 +       gdp = ext4_get_group_desc (sb, group, NULL);
 193 +       if (gdp == NULL)
 194 +               return -EIO;
 195 +
 196 +       /* before applying preallocations, check bitmap consistency */
 197 +       err = ext4_mb_check_ondisk_bitmap(sb, bitmap, gdp, group);
 198 +       if (err)
 199 +               return err;
 200 +
 201         /* all form of preallocation discards first load group,
 202          * so the only competing code is preallocation use.
 203          * we don't need any locking here
 204 @@ -3720,8 +3778,10 @@ static void ext4_mb_generate_from_pa(str
 205                                              &groupnr, &start);
 206                 len = pa->pa_len;
 207                 spin_unlock(&pa->pa_lock);
 208 -               if (unlikely(len == 0))
 209 +               if (unlikely(len == 0)) {
 210 +                       skip++;
 211                         continue;
 212 +               }
 213                 BUG_ON(groupnr != group);
 214                 mb_set_bits(bitmap, start, len);
 215                 preallocated += len;
 216 @@ -3729,6 +3789,7 @@ static void ext4_mb_generate_from_pa(str
 217                 count++;
 218         }
 219         mb_debug(1, "prellocated %u for group %u\n", preallocated, group);
 220 +       return 0;
 221  }
 222
 223  static void ext4_mb_pa_callback(struct rcu_head *head)
 224 @@ -3978,6 +4039,7 @@ ext4_mb_release_inode_pa(struct ext4_bud
 225         if (ac) {
 226                 ac->ac_sb = sb;
 227                 ac->ac_inode = pa->pa_inode;
 228 +               ac->ac_o_ex.fe_len = 1;
 229         }
 230
 231         while (bit < end) {
 232 @@ -4260,7 +4322,7 @@ repeat:
 233                 if (err) {
 234                         ext4_error(sb, __func__, "Error in loading buddy "
 235                                         "information for %u", group);
 236 -                       continue;
 237 +                       return;
 238                 }
 239
 240                 bitmap_bh = ext4_read_block_bitmap(sb, group);
 241 Index: linux-2.6.27.21-0.1/fs/ext4/mballoc.h
 242 ===================================================================
 243 --- linux-2.6.27.21-0.1.orig/fs/ext4/mballoc.h
 244 +++ linux-2.6.27.21-0.1/fs/ext4/mballoc.h
 245 @@ -92,7 +92,7 @@
 246  /*
 247   * for which requests use 2^N search using buddies
 248   */
 249 -#define MB_DEFAULT_ORDER2_REQS         2
 250 +#define MB_DEFAULT_ORDER2_REQS         8
 251
 252  /*
 253   * default group prealloc size 512 blocks