ldiskfs/kernel_patches/patches/ext3-uninit-2.6.18.patch

   1 Add support for the uninit_groups feature to the kernel.
   2
   3 Keep a high water mark of used inodes for each group to improve e2fsck time.
   4 Block and inode bitmaps can be uninitialized on disk via a flag in the
   5 group descriptor to avoid reading or scanning them at e2fsck time.
   6 A checksum of each group descriptor is used to ensure that corruption in
   7 the group descriptor's bit flags does not cause incorrect operation.
   8
   9 Index: linux-2.6.18.8.orig/include/linux/ext3_fs.h
  10 ===================================================================
  11 --- linux-2.6.18.8.orig.orig/include/linux/ext3_fs.h    2007-07-02 11:09:25.000000000 +0200
  12 +++ linux-2.6.18.8.orig/include/linux/ext3_fs.h 2007-07-02 11:09:31.000000000 +0200
  13 @@ -150,16 +150,22 @@ struct ext3_allocation_request {
  14   */
  15  struct ext3_group_desc
  16  {
  17 -       __le32  bg_block_bitmap;                /* Blocks bitmap block */
  18 -       __le32  bg_inode_bitmap;                /* Inodes bitmap block */
  19 +       __le32  bg_block_bitmap;        /* Blocks bitmap block */
  20 +       __le32  bg_inode_bitmap;        /* Inodes bitmap block */
  21         __le32  bg_inode_table;         /* Inodes table block */
  22         __le16  bg_free_blocks_count;   /* Free blocks count */
  23         __le16  bg_free_inodes_count;   /* Free inodes count */
  24         __le16  bg_used_dirs_count;     /* Directories count */
  25 -       __u16   bg_pad;
  26 -       __le32  bg_reserved[3];
  27 +       __le16  bg_flags;               /* EXT3_BG_flags (UNINIT, etc) */
  28 +       __le32  bg_reserved[2];         /* Likely block/inode bitmap checksum */
  29 +       __le16  bg_itable_unused;       /* Unused inodes count */
  30 +       __le16  bg_checksum;            /* crc16(sb_uuid+group+desc) */
  31  };
  32
  33 +#define EXT3_BG_INODE_UNINIT   0x0001 /* Inode table/bitmap not in use */
  34 +#define EXT3_BG_BLOCK_UNINIT   0x0002 /* Block bitmap not in use */
  35 +#define EXT3_BG_INODE_ZEROED   0x0004 /* On-disk itable initialized to zero */
  36 +
  37  /*
  38   * Macro-instructions used to manage group descriptors
  39   */
  40 @@ -603,6 +609,7 @@ static inline int ext3_valid_inum(struct
  41  #define EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER    0x0001
  42  #define EXT3_FEATURE_RO_COMPAT_LARGE_FILE      0x0002
  43  #define EXT3_FEATURE_RO_COMPAT_BTREE_DIR       0x0004
  44 +#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM                0x0010
  45  #define EXT4_FEATURE_RO_COMPAT_DIR_NLINK       0x0020
  46
  47  #define EXT3_FEATURE_INCOMPAT_COMPRESSION      0x0001
  48 @@ -619,6 +626,7 @@ static inline int ext3_valid_inum(struct
  49                                          EXT3_FEATURE_INCOMPAT_EXTENTS)
  50  #define EXT3_FEATURE_RO_COMPAT_SUPP    (EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
  51                                          EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
  52 +                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM| \
  53                                          EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
  54                                          EXT3_FEATURE_RO_COMPAT_BTREE_DIR)
  55
  56 Index: linux-2.6.18.8.orig/fs/ext3/resize.c
  57 ===================================================================
  58 --- linux-2.6.18.8.orig.orig/fs/ext3/resize.c   2007-06-21 14:53:15.000000000 +0200
  59 +++ linux-2.6.18.8.orig/fs/ext3/resize.c        2007-07-02 11:09:26.000000000 +0200
  60 @@ -18,6 +18,7 @@
  61  #include <linux/errno.h>
  62  #include <linux/slab.h>
  63
  64 +#include "group.h"
  65
  66  #define outside(b, first, last)        ((b) < (first) || (b) >= (last))
  67  #define inside(b, first, last) ((b) >= (first) && (b) < (last))
  68 @@ -822,6 +823,7 @@ int ext3_group_add(struct super_block *s
  69         gdp->bg_inode_table = cpu_to_le32(input->inode_table);
  70         gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
  71         gdp->bg_free_inodes_count = cpu_to_le16(EXT3_INODES_PER_GROUP(sb));
  72 +       gdp->bg_checksum = ext3_group_desc_csum(sbi, input->group, gdp);
  73
  74         /*
  75          * Make the new blocks and inodes valid next.  We do this before
  76 Index: linux-2.6.18.8.orig/fs/ext3/super.c
  77 ===================================================================
  78 --- linux-2.6.18.8.orig.orig/fs/ext3/super.c    2007-07-02 11:09:26.000000000 +0200
  79 +++ linux-2.6.18.8.orig/fs/ext3/super.c 2007-07-02 11:18:04.000000000 +0200
  80 @@ -41,6 +41,7 @@
  81  #include "xattr.h"
  82  #include "acl.h"
  83  #include "namei.h"
  84 +#include "group.h"
  85
  86  static int ext3_load_journal(struct super_block *, struct ext3_super_block *,
  87                              unsigned long journal_devnum);
  88 @@ -1225,6 +1226,91 @@ static int ext3_setup_super(struct super
  89         return res;
  90  }
  91
  92 +#if !defined(CONFIG_CRC16) && !defined(CONFIG_CRC16_MODULE)
  93 +/** CRC table for the CRC-16. The poly is 0x8005 (x^16 + x^15 + x^2 + 1) */
  94 +__u16 const crc16_table[256] = {
  95 +       0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
  96 +       0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
  97 +       0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
  98 +       0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
  99 +       0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
 100 +       0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
 101 +       0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
 102 +       0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
 103 +       0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
 104 +       0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
 105 +       0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
 106 +       0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
 107 +       0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
 108 +       0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
 109 +       0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
 110 +       0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
 111 +       0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
 112 +       0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
 113 +       0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
 114 +       0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
 115 +       0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
 116 +       0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
 117 +       0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
 118 +       0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
 119 +       0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
 120 +       0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
 121 +       0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
 122 +       0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
 123 +       0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
 124 +       0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
 125 +       0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
 126 +       0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
 127 +};
 128 +
 129 +static inline __u16 crc16_byte(__u16 crc, const __u8 data)
 130 +{
 131 +       return (crc >> 8) ^ crc16_table[(crc ^ data) & 0xff];
 132 +}
 133 +
 134 +__u16 crc16(__u16 crc, __u8 const *buffer, size_t len)
 135 +{
 136 +       while (len--)
 137 +               crc = crc16_byte(crc, *buffer++);
 138 +       return crc;
 139 +}
 140 +#endif
 141 +
 142 +__le16 ext3_group_desc_csum(struct ext3_sb_info *sbi, __u32 block_group,
 143 +                           struct ext3_group_desc *gdp)
 144 +{
 145 +       __u16 crc = 0;
 146 +
 147 +       if (sbi->s_es->s_feature_ro_compat &
 148 +           cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 149 +               int offset = offsetof(struct ext3_group_desc, bg_checksum);
 150 +               __le32 le_group = cpu_to_le32(block_group);
 151 +
 152 +               crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
 153 +               crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
 154 +               crc = crc16(crc, (__u8 *)gdp, offset);
 155 +               offset += sizeof(gdp->bg_checksum); /* skip checksum */
 156 +               BUG_ON(offset != sizeof(*gdp)); /* XXX handle s_desc_size */
 157 +               /* for checksum of struct ext4_group_desc do the rest...
 158 +               if ((sbi->s_es->s_feature_incompat &
 159 +                    cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
 160 +                    offset < le16_to_cpu(sbi->s_es->s_desc_size)) {
 161 +                       crc = crc16(crc, (__u8 *)gdp + offset,
 162 +                                   le16_to_cpu(sbi->s_es->s_desc_size) -
 163 +                                   offset);
 164 +               */
 165 +       }
 166 +
 167 +       return cpu_to_le16(crc);
 168 +}
 169 +
 170 +int ext3_group_desc_csum_verify(struct ext3_sb_info *sbi, __u32 block_group,
 171 +                               struct ext3_group_desc *gdp)
 172 +{
 173 +       return (gdp->bg_checksum ==
 174 +                       ext3_group_desc_csum(sbi, block_group, gdp));
 175 +}
 176 +
 177  /* Called at mount-time, super-block is locked */
 178  static int ext3_check_descriptors (struct super_block * sb)
 179  {
 180 @@ -1274,6 +1360,13 @@ static int ext3_check_descriptors (struc
 181                                         le32_to_cpu(gdp->bg_inode_table));
 182                         return 0;
 183                 }
 184 +               if (!ext3_group_desc_csum_verify(sbi, i, gdp)) {
 185 +                       ext3_error(sb, __FUNCTION__,
 186 +                                  "Checksum for group %d failed (%u!=%u)\n", i,
 187 +                                  le16_to_cpu(ext3_group_desc_csum(sbi,i,gdp)),
 188 +                                  le16_to_cpu(gdp->bg_checksum));
 189 +                       return 0;
 190 +               }
 191                 block += EXT3_BLOCKS_PER_GROUP(sb);
 192                 gdp++;
 193         }
 194 Index: linux-2.6.18.8.orig/fs/ext3/group.h
 195 ===================================================================
 196 --- /dev/null   1970-01-01 00:00:00.000000000 +0000
 197 +++ linux-2.6.18.8.orig/fs/ext3/group.h 2007-07-02 11:09:26.000000000 +0200
 198 @@ -0,0 +1,29 @@
 199 +/*
 200 + *  linux/fs/ext3/group.h
 201 + *
 202 + * Copyright (C) 2007 Cluster File Systems, Inc
 203 + *
 204 + * Author: Andreas Dilger <adilger@clusterfs.com>
 205 + */
 206 +
 207 +#ifndef _LINUX_EXT3_GROUP_H
 208 +#define _LINUX_EXT3_GROUP_H
 209 +#if defined(CONFIG_CRC16) || defined(CONFIG_CRC16_MODULE)
 210 +#include <linux/crc16.h>
 211 +#endif
 212 +
 213 +extern __le16 ext3_group_desc_csum(struct ext3_sb_info *sbi, __u32 group,
 214 +                                  struct ext3_group_desc *gdp);
 215 +extern int ext3_group_desc_csum_verify(struct ext3_sb_info *sbi, __u32 group,
 216 +                                      struct ext3_group_desc *gdp);
 217 +struct buffer_head *read_block_bitmap(struct super_block *sb,
 218 +                                     unsigned int block_group);
 219 +extern unsigned ext3_init_block_bitmap(struct super_block *sb,
 220 +                                      struct buffer_head *bh, int group,
 221 +                                      struct ext3_group_desc *desc);
 222 +#define ext3_free_blocks_after_init(sb, group, desc)                   \
 223 +               ext3_init_block_bitmap(sb, NULL, group, desc)
 224 +extern unsigned ext3_init_inode_bitmap(struct super_block *sb,
 225 +                                      struct buffer_head *bh, int group,
 226 +                                      struct ext3_group_desc *desc);
 227 +#endif /* _LINUX_EXT3_GROUP_H */
 228 Index: linux-2.6.18.8.orig/fs/ext3/ialloc.c
 229 ===================================================================
 230 --- linux-2.6.18.8.orig.orig/fs/ext3/ialloc.c   2007-07-02 11:09:26.000000000 +0200
 231 +++ linux-2.6.18.8.orig/fs/ext3/ialloc.c        2007-07-02 11:19:43.000000000 +0200
 232 @@ -28,6 +28,7 @@
 233
 234  #include "xattr.h"
 235  #include "acl.h"
 236 +#include "group.h"
 237
 238  /*
 239   * ialloc.c contains the inodes allocation and deallocation routines
 240 @@ -43,6 +44,52 @@
 241   * the free blocks count in the block.
 242   */
 243
 244 +/*
 245 + * To avoid calling the atomic setbit hundreds or thousands of times, we only
 246 + * need to use it within a single byte (to ensure we get endianness right).
 247 + * We can use memset for the rest of the bitmap as there are no other users.
 248 + */
 249 +static void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
 250 +{
 251 +       int i;
 252 +
 253 +       if (start_bit >= end_bit)
 254 +               return;
 255 +
 256 +       ext3_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
 257 +       for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
 258 +               ext3_set_bit(i, bitmap);
 259 +       if (i < end_bit)
 260 +               memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
 261 +}
 262 +
 263 +/* Initializes an uninitialized inode bitmap */
 264 +unsigned ext3_init_inode_bitmap(struct super_block *sb,
 265 +                               struct buffer_head *bh, int block_group,
 266 +                               struct ext3_group_desc *gdp)
 267 +{
 268 +       struct ext3_sb_info *sbi = EXT3_SB(sb);
 269 +
 270 +       J_ASSERT_BH(bh, buffer_locked(bh));
 271 +
 272 +       /* If checksum is bad mark all blocks and inodes used to prevent
 273 +        * allocation, essentially implementing a per-group read-only flag. */
 274 +       if (!ext3_group_desc_csum_verify(sbi, block_group, gdp)) {
 275 +               ext3_error(sb, __FUNCTION__, "Checksum bad for group %u\n",
 276 +                          block_group);
 277 +               gdp->bg_free_blocks_count = 0;
 278 +               gdp->bg_free_inodes_count = 0;
 279 +               gdp->bg_itable_unused = 0;
 280 +               memset(bh->b_data, 0xff, sb->s_blocksize);
 281 +               return 0;
 282 +       }
 283 +
 284 +       memset(bh->b_data, 0, (EXT3_INODES_PER_GROUP(sb) + 7) / 8);
 285 +       mark_bitmap_end(EXT3_INODES_PER_GROUP(sb), EXT3_BLOCKS_PER_GROUP(sb),
 286 +                       bh->b_data);
 287 +
 288 +       return EXT3_INODES_PER_GROUP(sb);
 289 +}
 290
 291  /*
 292   * Read the inode allocation bitmap for a given block_group, reading
 293 @@ -59,8 +106,19 @@ read_inode_bitmap(struct super_block * s
 294         desc = ext3_get_group_desc(sb, block_group, NULL);
 295         if (!desc)
 296                 goto error_out;
 297 -
 298 -       bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
 299 +       if (desc->bg_flags & cpu_to_le16(EXT3_BG_INODE_UNINIT)) {
 300 +               bh = sb_getblk(sb, le32_to_cpu(desc->bg_inode_bitmap));
 301 +               if (!buffer_uptodate(bh)) {
 302 +                       lock_buffer(bh);
 303 +                       if (!buffer_uptodate(bh)) {
 304 +                               ext3_init_inode_bitmap(sb, bh,block_group,desc);
 305 +                               set_buffer_uptodate(bh);
 306 +                       }
 307 +                       unlock_buffer(bh);
 308 +               }
 309 +       } else {
 310 +               bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
 311 +       }
 312         if (!bh)
 313                 ext3_error(sb, "read_inode_bitmap",
 314                             "Cannot read inode bitmap - "
 315 @@ -169,6 +227,8 @@ void ext3_free_inode (handle_t *handle,
 316                         if (is_directory)
 317                                 gdp->bg_used_dirs_count = cpu_to_le16(
 318                                   le16_to_cpu(gdp->bg_used_dirs_count) - 1);
 319 +                       gdp->bg_checksum = ext3_group_desc_csum(sbi,block_group,
 320 +                                                               gdp);
 321                         spin_unlock(sb_bgl_lock(sbi, block_group));
 322                         percpu_counter_inc(&sbi->s_freeinodes_counter);
 323                         if (is_directory)
 324 @@ -454,7 +514,7 @@ struct inode *ext3_new_inode(handle_t *h
 325         struct ext3_sb_info *sbi;
 326         int err = 0;
 327         struct inode *ret;
 328 -       int i;
 329 +       int i, free = 0;
 330
 331         /* Cannot create files in a deleted directory */
 332         if (!dir || !dir->i_nlink)
 333 @@ -571,11 +631,13 @@ repeat_in_this_group:
 334         goto out;
 335
 336  got:
 337 -       ino += group * EXT3_INODES_PER_GROUP(sb) + 1;
 338 -       if (ino < EXT3_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
 339 -               ext3_error (sb, "ext3_new_inode",
 340 -                           "reserved inode or inode > inodes count - "
 341 -                           "block_group = %d, inode=%lu", group, ino);
 342 +       ino++;
 343 +       if ((group == 0 && ino < EXT3_FIRST_INO(sb)) ||
 344 +           ino > EXT3_INODES_PER_GROUP(sb)) {
 345 +               ext3_error(sb, __FUNCTION__,
 346 +                          "reserved inode or inode > inodes count - "
 347 +                          "block_group = %d, inode=%lu", group,
 348 +                          ino + group * EXT3_INODES_PER_GROUP(sb));
 349                 err = -EIO;
 350                 goto fail;
 351         }
 352 @@ -583,13 +645,64 @@ got:
 353         BUFFER_TRACE(bh2, "get_write_access");
 354         err = ext3_journal_get_write_access(handle, bh2);
 355         if (err) goto fail;
 356 +
 357 +       /* We may have to initialize the block bitmap if it isn't already */
 358 +       if (EXT3_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 359 +           gdp->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
 360 +               struct buffer_head *block_bh = read_block_bitmap(sb, group);
 361 +
 362 +               BUFFER_TRACE(block_bh, "get block bitmap access");
 363 +               err = ext3_journal_get_write_access(handle, block_bh);
 364 +               if (err) {
 365 +                       brelse(block_bh);
 366 +                       goto fail;
 367 +               }
 368 +
 369 +               free = 0;
 370 +               spin_lock(sb_bgl_lock(sbi, group));
 371 +               /* recheck and clear flag under lock if we still need to */
 372 +               if (gdp->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
 373 +                       gdp->bg_flags &= cpu_to_le16(~EXT3_BG_BLOCK_UNINIT);
 374 +                       free = ext3_free_blocks_after_init(sb, group, gdp);
 375 +                       gdp->bg_free_blocks_count = cpu_to_le16(free);
 376 +               }
 377 +               spin_unlock(sb_bgl_lock(sbi, group));
 378 +
 379 +               /* Don't need to dirty bitmap block if we didn't change it */
 380 +               if (free) {
 381 +                       BUFFER_TRACE(block_bh, "dirty block bitmap");
 382 +                       err = ext3_journal_dirty_metadata(handle, block_bh);
 383 +               }
 384 +
 385 +               brelse(block_bh);
 386 +               if (err)
 387 +                       goto fail;
 388 +       }
 389 +
 390         spin_lock(sb_bgl_lock(sbi, group));
 391 +       /* If we didn't allocate from within the initialized part of the inode
 392 +        * table then we need to initialize up to this inode. */
 393 +       if (EXT3_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 394 +               if (gdp->bg_flags & cpu_to_le16(EXT3_BG_INODE_UNINIT)) {
 395 +                       gdp->bg_flags &= cpu_to_le16(~EXT3_BG_INODE_UNINIT);
 396 +                       free = EXT3_INODES_PER_GROUP(sb);
 397 +               } else {
 398 +                       free = EXT3_INODES_PER_GROUP(sb) -
 399 +                               le16_to_cpu(gdp->bg_itable_unused);
 400 +               }
 401 +
 402 +               if (ino > free)
 403 +                       gdp->bg_itable_unused =
 404 +                               cpu_to_le16(EXT3_INODES_PER_GROUP(sb) - ino);
 405 +       }
 406 +
 407         gdp->bg_free_inodes_count =
 408                 cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
 409         if (S_ISDIR(mode)) {
 410                 gdp->bg_used_dirs_count =
 411                         cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
 412         }
 413 +       gdp->bg_checksum = ext3_group_desc_csum(sbi, group, gdp);
 414         spin_unlock(sb_bgl_lock(sbi, group));
 415         BUFFER_TRACE(bh2, "call ext3_journal_dirty_metadata");
 416         err = ext3_journal_dirty_metadata(handle, bh2);
 417 @@ -611,7 +724,7 @@ got:
 418                 inode->i_gid = current->fsgid;
 419         inode->i_mode = mode;
 420
 421 -       inode->i_ino = ino;
 422 +       inode->i_ino = ino + group * EXT3_INODES_PER_GROUP(sb);
 423         /* This is the optimal IO size (for stat), not the fs block size */
 424         inode->i_blksize = PAGE_SIZE;
 425         inode->i_blocks = 0;
 426 Index: linux-2.6.18.8.orig/fs/ext3/mballoc.c
 427 ===================================================================
 428 --- linux-2.6.18.8.orig.orig/fs/ext3/mballoc.c  2007-07-02 11:09:25.000000000 +0200
 429 +++ linux-2.6.18.8.orig/fs/ext3/mballoc.c       2007-07-02 11:09:26.000000000 +0200
 430 @@ -36,6 +36,8 @@
 431  #include <linux/seq_file.h>
 432  #include <linux/version.h>
 433
 434 +#include "group.h"
 435 +
 436  /*
 437   * MUSTDO:
 438   *   - test ext3_ext_search_left() and ext3_ext_search_right()
 439 @@ -323,6 +325,7 @@ struct ext3_group_info {
 440         unsigned long   bb_state;
 441         unsigned long   bb_tid;
 442         struct ext3_free_metadata *bb_md_cur;
 443 +       struct ext3_group_desc *bb_gdp;
 444         unsigned short  bb_first_free;
 445         unsigned short  bb_free;
 446         unsigned short  bb_fragments;
 447 @@ -943,10 +946,7 @@ static int ext3_mb_init_cache(struct pag
 448                 if (first_group + i >= EXT3_SB(sb)->s_groups_count)
 449                         break;
 450
 451 -               err = -EIO;
 452 -               desc = ext3_get_group_desc(sb, first_group + i, NULL);
 453 -               if (desc == NULL)
 454 -                       goto out;
 455 +               desc = EXT3_GROUP_INFO(sb, first_group + i)->bb_gdp;
 456
 457                 err = -ENOMEM;
 458                 bh[i] = sb_getblk(sb, le32_to_cpu(desc->bg_block_bitmap));
 459 @@ -961,7 +961,12 @@ static int ext3_mb_init_cache(struct pag
 460                         unlock_buffer(bh[i]);
 461                         continue;
 462                 }
 463 -
 464 +               if (desc->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
 465 +                       ext3_init_block_bitmap(sb, bh[i], first_group + i,desc);
 466 +                       set_buffer_uptodate(bh[i]);
 467 +                       unlock_buffer(bh[i]);
 468 +                       continue;
 469 +               }
 470                 get_bh(bh[i]);
 471                 bh[i]->b_end_io = end_buffer_read_sync;
 472                 submit_bh(READ, bh[i]);
 473 @@ -1732,6 +1737,10 @@ static int ext3_mb_good_group(struct ext
 474         switch (cr) {
 475                 case 0:
 476                         BUG_ON(ac->ac_2order == 0);
 477 +                       /* If this group is uninitialized, skip it initially */
 478 +                       if (grp->bb_gdp->bg_flags &
 479 +                           cpu_to_le16(EXT3_BG_BLOCK_UNINIT))
 480 +                               return 0;
 481                         bits = ac->ac_sb->s_blocksize_bits + 1;
 482                         for (i = ac->ac_2order; i <= bits; i++)
 483                                 if (grp->bb_counters[i] > 0)
 484 @@ -1825,7 +1834,9 @@ repeat:
 485                         }
 486
 487                         ac->ac_groups_scanned++;
 488 -                       if (cr == 0)
 489 +                       if (cr == 0 || (e3b.bd_info->bb_gdp->bg_flags &
 490 +                                       cpu_to_le16(EXT3_BG_BLOCK_UNINIT) &&
 491 +                                       ac->ac_2order != 0))
 492                                 ext3_mb_simple_scan_group(ac, &e3b);
 493                         else if (cr == 1 && ac->ac_g_ex.fe_len == sbi->s_stripe)
 494                                 ext3_mb_scan_aligned(ac, &e3b);
 495 @@ -2304,12 +2315,13 @@ int ext3_mb_init_backend(struct super_bl
 496                         i--;
 497                         goto err_freebuddy;
 498                 }
 499 +               memset(meta_group_info[j], 0, len);
 500                 desc = ext3_get_group_desc(sb, i, NULL);
 501 +               meta_group_info[j]->bb_gdp = desc;
 502                 if (desc == NULL) {
 503                         printk(KERN_ERR"EXT3-fs: can't read descriptor %u\n",i);
 504                         goto err_freebuddy;
 505                 }
 506 -               memset(meta_group_info[j], 0, len);
 507                 set_bit(EXT3_GROUP_INFO_NEED_INIT_BIT,
 508                         &meta_group_info[j]->bb_state);
 509
 510 @@ -2972,9 +2984,17 @@ int ext3_mb_mark_diskspace_used(struct e
 511         mb_set_bits(bitmap_bh->b_data, ac->ac_b_ex.fe_start, ac->ac_b_ex.fe_len);
 512
 513         spin_lock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
 514 +       if (gdp->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
 515 +               gdp->bg_flags &= cpu_to_le16(~EXT3_BG_BLOCK_UNINIT);
 516 +               gdp->bg_free_blocks_count =
 517 +                       cpu_to_le16(ext3_free_blocks_after_init(sb,
 518 +                                                           ac->ac_b_ex.fe_group,
 519 +                                                           gdp));
 520 +       }
 521         gdp->bg_free_blocks_count =
 522                 cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)
 523                                 - ac->ac_b_ex.fe_len);
 524 +       gdp->bg_checksum = ext3_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp);
 525         spin_unlock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group));
 526         percpu_counter_mod(&sbi->s_freeblocks_counter, - ac->ac_b_ex.fe_len);
 527
 528 @@ -4343,6 +4363,7 @@ do_more:
 529         spin_lock(sb_bgl_lock(sbi, block_group));
 530         gdp->bg_free_blocks_count =
 531                 cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count) + count);
 532 +       gdp->bg_checksum = ext3_group_desc_csum(sbi, block_group, gdp);
 533         spin_unlock(sb_bgl_lock(sbi, block_group));
 534         percpu_counter_mod(&sbi->s_freeblocks_counter, count);
 535
 536 Index: linux-2.6.18.8.orig/fs/ext3/balloc.c
 537 ===================================================================
 538 --- linux-2.6.18.8.orig.orig/fs/ext3/balloc.c   2007-07-02 11:09:25.000000000 +0200
 539 +++ linux-2.6.18.8.orig/fs/ext3/balloc.c        2007-07-02 11:09:26.000000000 +0200
 540 @@ -20,6 +20,7 @@
 541  #include <linux/quotaops.h>
 542  #include <linux/buffer_head.h>
 543
 544 +#include "group.h"
 545  /*
 546   * balloc.c contains the blocks allocation and deallocation routines
 547   */
 548 @@ -73,6 +74,75 @@ struct ext3_group_desc * ext3_get_group_
 549         return desc + offset;
 550  }
 551
 552 +/* Initializes an uninitialized block bitmap if given, and returns the
 553 + * number of blocks free in the group. */
 554 +unsigned ext3_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
 555 +                               int block_group, struct ext3_group_desc *gdp)
 556 +{
 557 +       unsigned long start;
 558 +       int bit, bit_max;
 559 +       unsigned free_blocks;
 560 +       struct ext3_sb_info *sbi = EXT3_SB(sb);
 561 +
 562 +       if (bh) {
 563 +               J_ASSERT_BH(bh, buffer_locked(bh));
 564 +
 565 +               /* If checksum is bad mark all blocks use to prevent allocation,
 566 +                * essentially implementing a per-group read-only flag. */
 567 +               if (!ext3_group_desc_csum_verify(sbi, block_group, gdp)) {
 568 +                       ext3_error(sb, __FUNCTION__,
 569 +                                  "Checksum bad for group %u\n", block_group);
 570 +                       gdp->bg_free_blocks_count = 0;
 571 +                       gdp->bg_free_inodes_count = 0;
 572 +                       gdp->bg_itable_unused = 0;
 573 +                       memset(bh->b_data, 0xff, sb->s_blocksize);
 574 +                       return 0;
 575 +               }
 576 +               memset(bh->b_data, 0, sb->s_blocksize);
 577 +       }
 578 +
 579 +       /* Check for superblock and gdt backups in this group */
 580 +       bit_max = ext3_bg_has_super(sb, block_group);
 581 +
 582 +       if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_META_BG) ||
 583 +           block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) *
 584 +                         sbi->s_desc_per_block) {
 585 +               if (bit_max) {
 586 +                       bit_max += ext3_bg_num_gdb(sb, block_group);
 587 +                       bit_max +=le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks);
 588 +               }
 589 +       } else { /* For META_BG_BLOCK_GROUPS */
 590 +               int group_rel = (block_group -
 591 +                                le32_to_cpu(sbi->s_es->s_first_meta_bg)) %
 592 +                               EXT3_DESC_PER_BLOCK(sb);
 593 +               if (group_rel == 0 || group_rel == 1 ||
 594 +                   (group_rel == EXT3_DESC_PER_BLOCK(sb) - 1))
 595 +                       bit_max += 1;
 596 +       }
 597 +
 598 +       /* Last and first groups are always initialized */
 599 +       free_blocks = EXT3_BLOCKS_PER_GROUP(sb) - bit_max;
 600 +
 601 +       if (bh) {
 602 +               for (bit = 0; bit < bit_max; bit++)
 603 +                       ext3_set_bit(bit, bh->b_data);
 604 +
 605 +               start = block_group * EXT3_BLOCKS_PER_GROUP(sb) +
 606 +                       le32_to_cpu(sbi->s_es->s_first_data_block);
 607 +
 608 +               /* Set bits for block and inode bitmaps, and inode table */
 609 +               ext3_set_bit(le32_to_cpu(gdp->bg_block_bitmap) - start,
 610 +                            bh->b_data);
 611 +               ext3_set_bit(le32_to_cpu(gdp->bg_inode_bitmap) - start,
 612 +                            bh->b_data);
 613 +               for (bit = le32_to_cpu(gdp->bg_inode_table) - start,
 614 +                    bit_max = bit + sbi->s_itb_per_group; bit < bit_max; bit++)
 615 +                       ext3_set_bit(bit, bh->b_data);
 616 +       }
 617 +
 618 +       return free_blocks - sbi->s_itb_per_group - 2;
 619 +}
 620 +
 621  /*
 622   * Read the bitmap for a given block_group, reading into the specified
 623   * slot in the superblock's bitmap cache.
 624 @@ -88,7 +158,19 @@ read_block_bitmap(struct super_block *sb
 625         desc = ext3_get_group_desc (sb, block_group, NULL);
 626         if (!desc)
 627                 goto error_out;
 628 -       bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
 629 +       if (desc->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
 630 +               bh = sb_getblk(sb, le32_to_cpu(desc->bg_block_bitmap));
 631 +               if (!buffer_uptodate(bh)) {
 632 +                       lock_buffer(bh);
 633 +                       if (!buffer_uptodate(bh)) {
 634 +                               ext3_init_block_bitmap(sb, bh,block_group,desc);
 635 +                               set_buffer_uptodate(bh);
 636 +                       }
 637 +                       unlock_buffer(bh);
 638 +               }
 639 +       } else {
 640 +               bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
 641 +       }
 642         if (!bh)
 643                 ext3_error (sb, "read_block_bitmap",
 644                             "Cannot read block bitmap - "
 645 @@ -467,6 +549,7 @@ do_more:
 646         desc->bg_free_blocks_count =
 647                 cpu_to_le16(le16_to_cpu(desc->bg_free_blocks_count) +
 648                         group_freed);
 649 +       desc->bg_checksum = ext3_group_desc_csum(sbi, block_group, desc);
 650         spin_unlock(sb_bgl_lock(sbi, block_group));
 651         percpu_counter_mod(&sbi->s_freeblocks_counter, count);
 652
 653 @@ -1433,8 +1516,11 @@ allocated:
 654                         ret_block, goal_hits, goal_attempts);
 655
 656         spin_lock(sb_bgl_lock(sbi, group_no));
 657 +       if (gdp->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT))
 658 +               gdp->bg_flags &= cpu_to_le16(~EXT3_BG_BLOCK_UNINIT);
 659         gdp->bg_free_blocks_count =
 660                         cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count) - num);
 661 +       gdp->bg_checksum = ext3_group_desc_csum(sbi, group_no, gdp);
 662         spin_unlock(sb_bgl_lock(sbi, group_no));
 663         percpu_counter_mod(&sbi->s_freeblocks_counter, -num);
 664