ldiskfs/kernel_patches/patches/linux-5.4/ext4-data-in-dirent.patch

   1 diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
   2 index c7843b1..191304f 100644
   3 --- a/fs/ext4/dir.c
   4 +++ b/fs/ext4/dir.c
   5 @@ -70,11 +70,11 @@ int __ext4_check_dir_entry(const char *function, unsigned int line,
   6         const int rlen = ext4_rec_len_from_disk(de->rec_len,
   7                                                 dir->i_sb->s_blocksize);
   8
   9 -       if (unlikely(rlen < EXT4_DIR_REC_LEN(1)))
  10 +       if (unlikely(rlen < __EXT4_DIR_REC_LEN(1)))
  11                 error_msg = "rec_len is smaller than minimal";
  12         else if (unlikely(rlen % 4 != 0))
  13                 error_msg = "rec_len % 4 != 0";
  14 -       else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len)))
  15 +       else if (unlikely(rlen < EXT4_DIR_REC_LEN(de)))
  16                 error_msg = "rec_len is too small for name_len";
  17         else if (unlikely(((char *) de - buf) + rlen > size))
  18                 error_msg = "directory entry overrun";
  19 @@ -219,7 +219,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
  20                                  * failure will be detected in the
  21                                  * dirent test below. */
  22                                 if (ext4_rec_len_from_disk(de->rec_len,
  23 -                                       sb->s_blocksize) < EXT4_DIR_REC_LEN(1))
  24 +                                   sb->s_blocksize) < __EXT4_DIR_REC_LEN(1))
  25                                         break;
  26                                 i += ext4_rec_len_from_disk(de->rec_len,
  27                                                             sb->s_blocksize);
  28 @@ -442,12 +442,17 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
  29         struct fname *fname, *new_fn;
  30         struct dir_private_info *info;
  31         int len;
  32 +       int extra_data = 0;
  33
  34         info = dir_file->private_data;
  35         p = &info->root.rb_node;
  36
  37         /* Create and allocate the fname structure */
  38 -       len = sizeof(struct fname) + ent_name->len + 1;
  39 +       if (dirent->file_type & EXT4_DIRENT_LUFID)
  40 +               extra_data = ext4_get_dirent_data_len(dirent);
  41 +
  42 +       len = sizeof(struct fname) + ent_name->len + extra_data + 1;
  43 +
  44         new_fn = kzalloc(len, GFP_KERNEL);
  45         if (!new_fn)
  46                 return -ENOMEM;
  47 @@ -456,7 +461,7 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
  48         new_fn->inode = le32_to_cpu(dirent->inode);
  49         new_fn->name_len = ent_name->len;
  50         new_fn->file_type = dirent->file_type;
  51 -       memcpy(new_fn->name, ent_name->name, ent_name->len);
  52 +       memcpy(new_fn->name, ent_name->name, ent_name->len + extra_data);
  53         new_fn->name[ent_name->len] = 0;
  54
  55         while (*p) {
  56 diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
  57 index ce12383..e89e6ce 100644
  58 --- a/fs/ext4/ext4.h
  59 +++ b/fs/ext4/ext4.h
  60 @@ -1069,6 +1069,7 @@ struct ext4_inode_info {
  61         __u32 i_csum_seed;
  62
  63         kprojid_t i_projid;
  64 +       void *i_dirdata;
  65  };
  66
  67  /*
  68 @@ -1112,6 +1113,7 @@ struct ext4_inode_info {
  69  #define EXT4_MOUNT_POSIX_ACL           0x08000 /* POSIX Access Control Lists */
  70  #define EXT4_MOUNT_NO_AUTO_DA_ALLOC    0x10000 /* No auto delalloc mapping */
  71  #define EXT4_MOUNT_BARRIER             0x20000 /* Use block barriers */
  72 +#define EXT4_MOUNT_DIRDATA             0x40000 /* Data in directory entries*/
  73  #define EXT4_MOUNT_QUOTA               0x40000 /* Some quota option set */
  74  #define EXT4_MOUNT_USRQUOTA            0x80000 /* "old" user quota,
  75                                                  * enable enforcement for hidden
  76 @@ -1804,6 +1806,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(casefold,             CASEFOLD)
  77                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
  78                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
  79                                          EXT4_FEATURE_INCOMPAT_MMP | \
  80 +                                        EXT4_FEATURE_INCOMPAT_DIRDATA| \
  81                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
  82                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
  83                                          EXT4_FEATURE_INCOMPAT_CASEFOLD | \
  84 @@ -1980,6 +1983,43 @@ struct ext4_dir_entry_tail {
  85  #define EXT4_FT_SYMLINK                7
  86
  87  #define EXT4_FT_MAX            8
  88 +#define EXT4_FT_MASK           0xf
  89 +
  90 +#if EXT4_FT_MAX > EXT4_FT_MASK
  91 +#error "conflicting EXT4_FT_MAX and EXT4_FT_MASK"
  92 +#endif
  93 +
  94 +/*
  95 + * d_type has 4 unused bits, so it can hold four types data. these different
  96 + * type of data (e.g. lustre data, high 32 bits of 64-bit inode number) can be
  97 + * stored, in flag order, after file-name in ext4 dirent.
  98 +*/
  99 +/*
 100 + * this flag is added to d_type if ext4 dirent has extra data after
 101 + * filename. this data length is variable and length is stored in first byte
 102 + * of data. data start after filename NUL byte.
 103 + * This is used by Lustre FS.
 104 +  */
 105 +#define EXT4_DIRENT_LUFID              0x10
 106 +
 107 +#define EXT4_LUFID_MAGIC    0xAD200907UL
 108 +struct ext4_dentry_param {
 109 +       __u32  edp_magic;       /* EXT4_LUFID_MAGIC */
 110 +       char   edp_len;         /* size of edp_data in bytes */
 111 +       char   edp_data[0];     /* packed array of data */
 112 +} __packed;
 113 +
 114 +static inline unsigned char *ext4_dentry_get_data(struct super_block *sb,
 115 +                                                 struct ext4_dentry_param *p)
 116 +
 117 +{
 118 +       if (!ext4_has_feature_dirdata(sb))
 119 +               return NULL;
 120 +       if (p && p->edp_magic == EXT4_LUFID_MAGIC)
 121 +               return &p->edp_len;
 122 +       else
 123 +               return NULL;
 124 +}
 125
 126  #define EXT4_FT_DIR_CSUM       0xDE
 127
 128 @@ -1990,8 +2030,11 @@ struct ext4_dir_entry_tail {
 129   */
 130  #define EXT4_DIR_PAD                   4
 131  #define EXT4_DIR_ROUND                 (EXT4_DIR_PAD - 1)
 132 -#define EXT4_DIR_REC_LEN(name_len)     (((name_len) + 8 + EXT4_DIR_ROUND) & \
 133 +#define __EXT4_DIR_REC_LEN(name_len)   (((name_len) + 8 + EXT4_DIR_ROUND) & \
 134                                          ~EXT4_DIR_ROUND)
 135 +#define EXT4_DIR_REC_LEN(de)           (__EXT4_DIR_REC_LEN((de)->name_len +\
 136 +                                       ext4_get_dirent_data_len(de)))
 137 +
 138  #define EXT4_MAX_REC_LEN               ((1<<16)-1)
 139
 140  /*
 141 @@ -2418,11 +2461,11 @@ extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 142                              struct buffer_head *bh,
 143                              void *buf, int buf_size,
 144                              struct ext4_filename *fname,
 145 -                            struct ext4_dir_entry_2 **dest_de);
 146 +                            struct ext4_dir_entry_2 **dest_de, int *dlen);
 147  void ext4_insert_dentry(struct inode *inode,
 148                         struct ext4_dir_entry_2 *de,
 149                         int buf_size,
 150 -                       struct ext4_filename *fname);
 151 +                       struct ext4_filename *fname, void *data);
 152  static inline void ext4_update_dx_flag(struct inode *inode)
 153  {
 154         if (!ext4_has_feature_dir_index(inode->i_sb))
 155 @@ -2434,10 +2477,17 @@ static const unsigned char ext4_filetype_table[] = {
 156
 157  static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
 158  {
 159 -       if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
 160 +       int fl_index = filetype & EXT4_FT_MASK;
 161 +
 162 +       if (!ext4_has_feature_filetype(sb) || fl_index >= EXT4_FT_MAX)
 163                 return DT_UNKNOWN;
 164
 165 -       return ext4_filetype_table[filetype];
 166 +       if (!test_opt(sb, DIRDATA))
 167 +               return ext4_filetype_table[fl_index];
 168 +
 169 +       return (ext4_filetype_table[fl_index]) |
 170 +               (filetype & EXT4_DIRENT_LUFID);
 171 +
 172  }
 173  extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
 174                              void *buf, int buf_size);
 175 @@ -2600,6 +2650,8 @@ extern struct inode *ext4_create_inode(handle_t *handle,
 176  extern int ext4_delete_entry(handle_t *handle, struct inode * dir,
 177                              struct ext4_dir_entry_2 *de_del,
 178                              struct buffer_head *bh);
 179 +extern int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
 180 +                              struct inode *inode, const void *, const void *);
 181  extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 182                                 __u32 start_minor_hash, __u32 *next_hash);
 183  extern int ext4_search_dir(struct buffer_head *bh,
 184 @@ -3335,6 +3387,36 @@ static inline void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end)
 185
 186  extern const struct iomap_ops ext4_iomap_ops;
 187
 188 +/*
 189 + * Compute the total directory entry data length.
 190 + * This includes the filename and an implicit NUL terminator (always present),
 191 + * and optional extensions.  Each extension has a bit set in the high 4 bits of
 192 + * de->file_type, and the extension length is the first byte in each entry.
 193 + */
 194 +static inline int ext4_get_dirent_data_len(struct ext4_dir_entry_2 *de)
 195 +{
 196 +       char *len = de->name + de->name_len + 1 /* NUL terminator */;
 197 +       int dlen = 0;
 198 +       __u8 extra_data_flags = (de->file_type & ~EXT4_FT_MASK) >> 4;
 199 +       struct ext4_dir_entry_tail *t = (struct ext4_dir_entry_tail *)de;
 200 +
 201 +       if (!t->det_reserved_zero1 &&
 202 +           le16_to_cpu(t->det_rec_len) ==
 203 +               sizeof(struct ext4_dir_entry_tail) &&
 204 +           !t->det_reserved_zero2 &&
 205 +           t->det_reserved_ft == EXT4_FT_DIR_CSUM)
 206 +               return 0;
 207 +
 208 +       while (extra_data_flags) {
 209 +               if (extra_data_flags & 1) {
 210 +                       dlen += *len + (dlen == 0);
 211 +                       len += *len;
 212 +               }
 213 +               extra_data_flags >>= 1;
 214 +       }
 215 +       return dlen;
 216 +}
 217 +
 218  #endif /* __KERNEL__ */
 219
 220  #define EFSBADCRC      EBADMSG         /* Bad CRC detected */
 221 diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
 222 index f73bc39..7610cfe 100644
 223 --- a/fs/ext4/inline.c
 224 +++ b/fs/ext4/inline.c
 225 @@ -1023,7 +1023,7 @@ static int ext4_add_dirent_to_inline(handle_t *handle,
 226         struct ext4_dir_entry_2 *de;
 227
 228         err = ext4_find_dest_de(dir, inode, iloc->bh, inline_start,
 229 -                               inline_size, fname, &de);
 230 +                               inline_size, fname, &de, NULL);
 231         if (err)
 232                 return err;
 233
 234 @@ -1031,7 +1031,7 @@ static int ext4_add_dirent_to_inline(handle_t *handle,
 235         err = ext4_journal_get_write_access(handle, iloc->bh);
 236         if (err)
 237                 return err;
 238 -       ext4_insert_dentry(inode, de, inline_size, fname);
 239 +       ext4_insert_dentry(inode, de, inline_size, fname, NULL);
 240
 241         ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
 242
 243 @@ -1100,7 +1100,7 @@ static int ext4_update_inline_dir(handle_t *handle, struct inode *dir,
 244         int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
 245         int new_size = get_max_inline_xattr_value_size(dir, iloc);
 246
 247 -       if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
 248 +       if (new_size - old_size <= __EXT4_DIR_REC_LEN(1))
 249                 return -ENOSPC;
 250
 251         ret = ext4_update_inline_data(handle, dir,
 252 @@ -1381,7 +1381,7 @@ int htree_inlinedir_to_tree(struct file *dir_file,
 253                         fake.name_len = 1;
 254                         strcpy(fake.name, ".");
 255                         fake.rec_len = ext4_rec_len_to_disk(
 256 -                                               EXT4_DIR_REC_LEN(fake.name_len),
 257 +                                               EXT4_DIR_REC_LEN(&fake),
 258                                                 inline_size);
 259                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 260                         de = &fake;
 261 @@ -1391,7 +1391,7 @@ int htree_inlinedir_to_tree(struct file *dir_file,
 262                         fake.name_len = 2;
 263                         strcpy(fake.name, "..");
 264                         fake.rec_len = ext4_rec_len_to_disk(
 265 -                                               EXT4_DIR_REC_LEN(fake.name_len),
 266 +                                               EXT4_DIR_REC_LEN(&fake),
 267                                                 inline_size);
 268                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 269                         de = &fake;
 270 @@ -1489,8 +1489,8 @@ int ext4_read_inline_dir(struct file *file,
 271          * So we will use extra_offset and extra_size to indicate them
 272          * during the inline dir iteration.
 273          */
 274 -       dotdot_offset = EXT4_DIR_REC_LEN(1);
 275 -       dotdot_size = dotdot_offset + EXT4_DIR_REC_LEN(2);
 276 +       dotdot_offset = __EXT4_DIR_REC_LEN(1);
 277 +       dotdot_size = dotdot_offset + __EXT4_DIR_REC_LEN(2);
 278         extra_offset = dotdot_size - EXT4_INLINE_DOTDOT_SIZE;
 279         extra_size = extra_offset + inline_size;
 280
 281 @@ -1525,7 +1525,7 @@ int ext4_read_inline_dir(struct file *file,
 282                          * failure will be detected in the
 283                          * dirent test below. */
 284                         if (ext4_rec_len_from_disk(de->rec_len, extra_size)
 285 -                               < EXT4_DIR_REC_LEN(1))
 286 +                               < __EXT4_DIR_REC_LEN(1))
 287                                 break;
 288                         i += ext4_rec_len_from_disk(de->rec_len,
 289                                                     extra_size);
 290 diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
 291 index be8c35d..7c09936 100644
 292 --- a/fs/ext4/namei.c
 293 +++ b/fs/ext4/namei.c
 294 @@ -245,7 +245,8 @@ static unsigned dx_get_count(struct dx_entry *entries);
 295  static unsigned dx_get_limit(struct dx_entry *entries);
 296  static void dx_set_count(struct dx_entry *entries, unsigned value);
 297  static void dx_set_limit(struct dx_entry *entries, unsigned value);
 298 -static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
 299 +static inline unsigned dx_root_limit(struct inode *dir,
 300 +               struct ext4_dir_entry_2 *dot_de, unsigned infosize);
 301  static unsigned dx_node_limit(struct inode *dir);
 302  static struct dx_frame *dx_probe(struct ext4_filename *fname,
 303                                  struct inode *dir,
 304 @@ -388,22 +389,23 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 305  {
 306         struct ext4_dir_entry *dp;
 307         struct dx_root_info *root;
 308 -       int count_offset;
 309 +       int count_offset, dot_rec_len, dotdot_rec_len;
 310
 311         if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
 312                 count_offset = 8;
 313 -       else if (le16_to_cpu(dirent->rec_len) == 12) {
 314 -               dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
 315 +       else {
 316 +               dot_rec_len = le16_to_cpu(dirent->rec_len);
 317 +               dp = (struct ext4_dir_entry *)(((void *)dirent) + dot_rec_len);
 318                 if (le16_to_cpu(dp->rec_len) !=
 319 -                   EXT4_BLOCK_SIZE(inode->i_sb) - 12)
 320 +                   EXT4_BLOCK_SIZE(inode->i_sb) - dot_rec_len)
 321                         return NULL;
 322 -               root = (struct dx_root_info *)(((void *)dp + 12));
 323 +               dotdot_rec_len = EXT4_DIR_REC_LEN((struct ext4_dir_entry_2 *)dp);
 324 +               root = (struct dx_root_info *)(((void *)dp + dotdot_rec_len));
 325                 if (root->reserved_zero ||
 326                     root->info_length != sizeof(struct dx_root_info))
 327                         return NULL;
 328 -               count_offset = 32;
 329 -       } else
 330 -               return NULL;
 331 +               count_offset = 8 + dot_rec_len + dotdot_rec_len;
 332 +       }
 333
 334         if (offset)
 335                 *offset = count_offset;
 336 @@ -508,11 +510,12 @@ ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
 337   */
 338  struct dx_root_info *dx_get_dx_info(struct ext4_dir_entry_2 *de)
 339  {
 340 +       BUG_ON(de->name_len != 1);
 341         /* get dotdot first */
 342 -       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(1));
 343 +       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(de));
 344
 345         /* dx root info is after dotdot entry */
 346 -       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(2));
 347 +       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(de));
 348
 349         return (struct dx_root_info *)de;
 350  }
 351 @@ -557,10 +560,16 @@ static inline void dx_set_limit(struct dx_entry *entries, unsigned value)
 352         ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
 353  }
 354
 355 -static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
 356 +static inline unsigned dx_root_limit(struct inode *dir,
 357 +               struct ext4_dir_entry_2 *dot_de, unsigned infosize)
 358  {
 359 -       unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
 360 -               EXT4_DIR_REC_LEN(2) - infosize;
 361 +       struct ext4_dir_entry_2 *dotdot_de;
 362 +       unsigned entry_space;
 363 +
 364 +       BUG_ON(dot_de->name_len != 1);
 365 +       dotdot_de = ext4_next_entry(dot_de, dir->i_sb->s_blocksize);
 366 +       entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(dot_de) -
 367 +                        EXT4_DIR_REC_LEN(dotdot_de) - infosize;
 368
 369         if (ext4_has_metadata_csum(dir->i_sb))
 370                 entry_space -= sizeof(struct dx_tail);
 371 @@ -569,7 +578,7 @@ static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
 372
 373  static inline unsigned dx_node_limit(struct inode *dir)
 374  {
 375 -       unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
 376 +       unsigned entry_space = dir->i_sb->s_blocksize - __EXT4_DIR_REC_LEN(0);
 377
 378         if (ext4_has_metadata_csum(dir->i_sb))
 379                 entry_space -= sizeof(struct dx_tail);
 380 @@ -681,7 +690,7 @@ static struct stats dx_show_leaf(struct inode *dir,
 381                                        (unsigned) ((char *) de - base));
 382  #endif
 383                         }
 384 -                       space += EXT4_DIR_REC_LEN(de->name_len);
 385 +                       space += EXT4_DIR_REC_LEN(de);
 386                         names++;
 387                 }
 388                 de = ext4_next_entry(de, size);
 389 @@ -788,11 +797,14 @@ dx_probe(struct ext4_filename *fname, struct inode *dir,
 390
 391         entries = (struct dx_entry *)(((char *)info) + info->info_length);
 392
 393 -       if (dx_get_limit(entries) != dx_root_limit(dir,
 394 -                                                  info->info_length)) {
 395 +       if (dx_get_limit(entries) !=
 396 +           dx_root_limit(dir, (struct ext4_dir_entry_2 *)frame->bh->b_data,
 397 +                         info->info_length)) {
 398                 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
 399                                    dx_get_limit(entries),
 400 -                                  dx_root_limit(dir, info->info_length));
 401 +                                  dx_root_limit(dir,
 402 +                                         (struct ext4_dir_entry_2 *)frame->bh->b_data,
 403 +                                         info->info_length));
 404                 goto fail;
 405         }
 406
 407 @@ -987,7 +999,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
 408         de = (struct ext4_dir_entry_2 *) bh->b_data;
 409         top = (struct ext4_dir_entry_2 *) ((char *) de +
 410                                            dir->i_sb->s_blocksize -
 411 -                                          EXT4_DIR_REC_LEN(0));
 412 +                                          __EXT4_DIR_REC_LEN(0));
 413  #ifdef CONFIG_FS_ENCRYPTION
 414         /* Check if the directory is encrypted */
 415         if (IS_ENCRYPTED(dir)) {
 416 @@ -1741,7 +1753,7 @@ dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
 417         while (count--) {
 418                 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
 419                                                 (from + (map->offs<<2));
 420 -               rec_len = EXT4_DIR_REC_LEN(de->name_len);
 421 +               rec_len = EXT4_DIR_REC_LEN(de);
 422                 memcpy (to, de, rec_len);
 423                 ((struct ext4_dir_entry_2 *) to)->rec_len =
 424                                 ext4_rec_len_to_disk(rec_len, blocksize);
 425 @@ -1765,7 +1777,7 @@ static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
 426         while ((char*)de < base + blocksize) {
 427                 next = ext4_next_entry(de, blocksize);
 428                 if (de->inode && de->name_len) {
 429 -                       rec_len = EXT4_DIR_REC_LEN(de->name_len);
 430 +                       rec_len = EXT4_DIR_REC_LEN(de);
 431                         if (de > to)
 432                                 memmove(to, de, rec_len);
 433                         to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
 434 @@ -1896,14 +1908,16 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 435                       struct buffer_head *bh,
 436                       void *buf, int buf_size,
 437                       struct ext4_filename *fname,
 438 -                     struct ext4_dir_entry_2 **dest_de)
 439 +                     struct ext4_dir_entry_2 **dest_de, int *dlen)
 440  {
 441         struct ext4_dir_entry_2 *de;
 442 -       unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
 443 +       unsigned short reclen = __EXT4_DIR_REC_LEN(fname_len(fname)) +
 444 +                                                 (dlen ? *dlen : 0);
 445         int nlen, rlen;
 446         unsigned int offset = 0;
 447         char *top;
 448
 449 +       dlen ? *dlen = 0 : 0; /* default set to 0 */
 450         de = (struct ext4_dir_entry_2 *)buf;
 451         top = buf + buf_size - reclen;
 452         while ((char *) de <= top) {
 453 @@ -1912,10 +1926,26 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 454                         return -EFSCORRUPTED;
 455                 if (ext4_match(dir, fname, de))
 456                         return -EEXIST;
 457 -               nlen = EXT4_DIR_REC_LEN(de->name_len);
 458 +               nlen = EXT4_DIR_REC_LEN(de);
 459                 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 460                 if ((de->inode ? rlen - nlen : rlen) >= reclen)
 461                         break;
 462 +               /* Then for dotdot entries, check for the smaller space
 463 +                * required for just the entry, no FID */
 464 +               if (fname_len(fname) == 2 && memcmp(fname_name(fname), "..", 2) == 0) {
 465 +                       if ((de->inode ? rlen - nlen : rlen) >=
 466 +                           __EXT4_DIR_REC_LEN(fname_len(fname))) {
 467 +                               /* set dlen=1 to indicate not
 468 +                                * enough space store fid */
 469 +                               dlen ? *dlen = 1 : 0;
 470 +                               break;
 471 +                       }
 472 +                       /* The new ".." entry must be written over the
 473 +                        * previous ".." entry, which is the first
 474 +                        * entry traversed by this scan. If it doesn't
 475 +                        * fit, something is badly wrong, so -EIO. */
 476 +                       return -EIO;
 477 +               }
 478                 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
 479                 offset += rlen;
 480         }
 481 @@ -1929,12 +1959,12 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 482  void ext4_insert_dentry(struct inode *inode,
 483                         struct ext4_dir_entry_2 *de,
 484                         int buf_size,
 485 -                       struct ext4_filename *fname)
 486 +                       struct ext4_filename *fname, void *data)
 487  {
 488
 489         int nlen, rlen;
 490
 491 -       nlen = EXT4_DIR_REC_LEN(de->name_len);
 492 +       nlen = EXT4_DIR_REC_LEN(de);
 493         rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 494         if (de->inode) {
 495                 struct ext4_dir_entry_2 *de1 =
 496 @@ -1948,6 +1978,11 @@ void ext4_insert_dentry(struct inode *inode,
 497         ext4_set_de_type(inode->i_sb, de, inode->i_mode);
 498         de->name_len = fname_len(fname);
 499         memcpy(de->name, fname_name(fname), fname_len(fname));
 500 +       if (data) {
 501 +               de->name[fname_len(fname)] = 0;
 502 +               memcpy(&de->name[fname_len(fname) + 1], data, *(char *)data);
 503 +               de->file_type |= EXT4_DIRENT_LUFID;
 504 +       }
 505  }
 506
 507  /*
 508 @@ -1965,14 +2000,19 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
 509  {
 510         unsigned int    blocksize = dir->i_sb->s_blocksize;
 511         int             csum_size = 0;
 512 -       int             err;
 513 +       int             err, dlen = 0;
 514 +       unsigned char   *data;
 515
 516 +       data = ext4_dentry_get_data(inode->i_sb, (struct ext4_dentry_param *)
 517 +                                               EXT4_I(inode)->i_dirdata);
 518         if (ext4_has_metadata_csum(inode->i_sb))
 519                 csum_size = sizeof(struct ext4_dir_entry_tail);
 520
 521         if (!de) {
 522 +               if (data)
 523 +                       dlen = (*data) + 1;
 524                 err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
 525 -                                       blocksize - csum_size, fname, &de);
 526 +                                       blocksize - csum_size, fname, &de, &dlen);
 527                 if (err)
 528                         return err;
 529         }
 530 @@ -1984,7 +2024,10 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
 531         }
 532
 533         /* By now the buffer is marked for journaling */
 534 -       ext4_insert_dentry(inode, de, blocksize, fname);
 535 +       /* If writing the short form of "dotdot", don't add the data section */
 536 +       if (dlen == 1)
 537 +               data = NULL;
 538 +       ext4_insert_dentry(inode, de, blocksize, fname, data);
 539
 540         /*
 541          * XXX shouldn't update any times until successful
 542 @@ -2093,7 +2136,8 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
 543
 544         dx_set_block(entries, 1);
 545         dx_set_count(entries, 1);
 546 -       dx_set_limit(entries, dx_root_limit(dir, sizeof(*dx_info)));
 547 +       dx_set_limit(entries, dx_root_limit(dir,
 548 +                                        dot_de, sizeof(*dx_info)));
 549
 550         /* Initialize as for dx_probe */
 551         fname->hinfo.hash_version = dx_info->hash_version;
 552 @@ -2143,6 +2187,8 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 553         struct buffer_head *dir_block;
 554         struct ext4_dir_entry_2 *de;
 555         int len, journal = 0, err = 0;
 556 +       int dlen = 0;
 557 +       char *data;
 558
 559         if (IS_ERR(handle))
 560                 return PTR_ERR(handle);
 561 @@ -2160,19 +2206,24 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 562         /* the first item must be "." */
 563         assert(de->name_len == 1 && de->name[0] == '.');
 564         len = le16_to_cpu(de->rec_len);
 565 -       assert(len >= EXT4_DIR_REC_LEN(1));
 566 -       if (len > EXT4_DIR_REC_LEN(1)) {
 567 +       assert(len >= __EXT4_DIR_REC_LEN(1));
 568 +       if (len > __EXT4_DIR_REC_LEN(1)) {
 569                 BUFFER_TRACE(dir_block, "get_write_access");
 570                 err = ext4_journal_get_write_access(handle, dir_block);
 571                 if (err)
 572                         goto out_journal;
 573
 574                 journal = 1;
 575 -               de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(1));
 576 +               de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de));
 577         }
 578
 579 -       len -= EXT4_DIR_REC_LEN(1);
 580 -       assert(len == 0 || len >= EXT4_DIR_REC_LEN(2));
 581 +       len -= EXT4_DIR_REC_LEN(de);
 582 +       data = ext4_dentry_get_data(dir->i_sb,
 583 +                       (struct ext4_dentry_param *)dentry->d_fsdata);
 584 +       if (data)
 585 +               dlen = *data + 1;
 586 +       assert(len == 0 || len >= __EXT4_DIR_REC_LEN(2 + dlen));
 587 +
 588         de = (struct ext4_dir_entry_2 *)
 589                         ((char *) de + le16_to_cpu(de->rec_len));
 590         if (!journal) {
 591 @@ -2186,10 +2237,15 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
 592         if (len > 0)
 593                 de->rec_len = cpu_to_le16(len);
 594         else
 595 -               assert(le16_to_cpu(de->rec_len) >= EXT4_DIR_REC_LEN(2));
 596 +               assert(le16_to_cpu(de->rec_len) >= __EXT4_DIR_REC_LEN(2));
 597         de->name_len = 2;
 598         strcpy(de->name, "..");
 599 -       ext4_set_de_type(dir->i_sb, de, S_IFDIR);
 600 +       if (data != NULL && ext4_get_dirent_data_len(de) >= dlen) {
 601 +               de->name[2] = 0;
 602 +               memcpy(&de->name[2 + 1], data, *data);
 603 +               ext4_set_de_type(dir->i_sb, de, S_IFDIR);
 604 +               de->file_type |= EXT4_DIRENT_LUFID;
 605 +       }
 606
 607  out_journal:
 608         if (journal) {
 609 @@ -2229,6 +2285,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
 610         ext4_lblk_t block, blocks;
 611         int     csum_size = 0;
 612
 613 +       EXT4_I(inode)->i_dirdata = dentry->d_fsdata;
 614         if (ext4_has_metadata_csum(inode->i_sb))
 615                 csum_size = sizeof(struct ext4_dir_entry_tail);
 616
 617 @@ -2757,37 +2814,70 @@ err_unlock_inode:
 618         return err;
 619  }
 620
 621 +struct tp_block {
 622 +       struct inode *inode;
 623 +       void *data1;
 624 +       void *data2;
 625 +};
 626 +
 627  struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
 628                           struct ext4_dir_entry_2 *de,
 629                           int blocksize, int csum_size,
 630                           unsigned int parent_ino, int dotdot_real_len)
 631  {
 632 +       void *data1 = NULL, *data2 = NULL;
 633 +       int dot_reclen = 0;
 634 +
 635 +       if (dotdot_real_len == 10) {
 636 +               struct tp_block *tpb = (struct tp_block *)inode;
 637 +               data1 = tpb->data1;
 638 +               data2 = tpb->data2;
 639 +               inode = tpb->inode;
 640 +               dotdot_real_len = 0;
 641 +       }
 642         de->inode = cpu_to_le32(inode->i_ino);
 643         de->name_len = 1;
 644 -       de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
 645 -                                          blocksize);
 646         strcpy(de->name, ".");
 647         ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 648
 649 +       /* get packed fid data*/
 650 +       data1 = ext4_dentry_get_data(inode->i_sb,
 651 +                               (struct ext4_dentry_param *) data1);
 652 +       if (data1) {
 653 +               de->name[1] = 0;
 654 +               memcpy(&de->name[2], data1, *(char *) data1);
 655 +               de->file_type |= EXT4_DIRENT_LUFID;
 656 +       }
 657 +       de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de));
 658 +       dot_reclen = cpu_to_le16(de->rec_len);
 659         de = ext4_next_entry(de, blocksize);
 660         de->inode = cpu_to_le32(parent_ino);
 661         de->name_len = 2;
 662 +       strcpy(de->name, "..");
 663 +       ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 664 +       data2 = ext4_dentry_get_data(inode->i_sb,
 665 +                       (struct ext4_dentry_param *) data2);
 666 +       if (data2) {
 667 +               de->name[2] = 0;
 668 +               memcpy(&de->name[3], data2, *(char *) data2);
 669 +               de->file_type |= EXT4_DIRENT_LUFID;
 670 +       }
 671         if (!dotdot_real_len)
 672                 de->rec_len = ext4_rec_len_to_disk(blocksize -
 673 -                                       (csum_size + EXT4_DIR_REC_LEN(1)),
 674 +                                       (csum_size + dot_reclen),
 675                                         blocksize);
 676         else
 677                 de->rec_len = ext4_rec_len_to_disk(
 678 -                               EXT4_DIR_REC_LEN(de->name_len), blocksize);
 679 -       strcpy(de->name, "..");
 680 -       ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 681 +                               EXT4_DIR_REC_LEN(de), blocksize);
 682
 683         return ext4_next_entry(de, blocksize);
 684  }
 685
 686  static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 687 -                            struct inode *inode)
 688 +                            struct inode *inode,
 689 +                            const void *data1, const void *data2)
 690  {
 691 +       struct tp_block param;
 692         struct buffer_head *dir_block = NULL;
 693         struct ext4_dir_entry_2 *de;
 694         struct ext4_dir_entry_tail *t;
 695 @@ -2812,7 +2902,11 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 696         if (IS_ERR(dir_block))
 697                 return PTR_ERR(dir_block);
 698         de = (struct ext4_dir_entry_2 *)dir_block->b_data;
 699 -       ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
 700 +       param.inode = inode;
 701 +       param.data1 = (void *)data1;
 702 +       param.data2 = (void *)data2;
 703 +       ext4_init_dot_dotdot((struct inode *)(&param), de, blocksize,
 704 +                            csum_size, dir->i_ino, 10);
 705         set_nlink(inode, 2);
 706         if (csum_size) {
 707                 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
 708 @@ -2829,6 +2923,29 @@ out:
 709         return err;
 710  }
 711
 712 +/* Initialize @inode as a subdirectory of @dir, and add the
 713 + * "." and ".." entries into the first directory block. */
 714 +int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
 715 +                       struct inode *inode,
 716 +                       const void *data1, const void *data2)
 717 +{
 718 +       int rc;
 719 +
 720 +       if (IS_ERR(handle))
 721 +               return PTR_ERR(handle);
 722 +
 723 +       if (IS_DIRSYNC(dir))
 724 +               ext4_handle_sync(handle);
 725 +
 726 +       inode->i_op = &ext4_dir_inode_operations;
 727 +       inode->i_fop = &ext4_dir_operations;
 728 +       rc = ext4_init_new_dir(handle, dir, inode, data1, data2);
 729 +       if (!rc)
 730 +               rc = ext4_mark_inode_dirty(handle, inode);
 731 +       return rc;
 732 +}
 733 +EXPORT_SYMBOL(ext4_add_dot_dotdot);
 734 +
 735  static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 736  {
 737         handle_t *handle;
 738 @@ -2855,7 +2972,7 @@ retry:
 739
 740         inode->i_op = &ext4_dir_inode_operations;
 741         inode->i_fop = &ext4_dir_operations;
 742 -       err = ext4_init_new_dir(handle, dir, inode);
 743 +       err = ext4_init_new_dir(handle, dir, inode, NULL, NULL);
 744         if (err)
 745                 goto out_clear_inode;
 746         err = ext4_mark_inode_dirty(handle, inode);
 747 @@ -2906,7 +3023,7 @@ bool ext4_empty_dir(struct inode *inode)
 748         }
 749
 750         sb = inode->i_sb;
 751 -       if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
 752 +       if (inode->i_size < __EXT4_DIR_REC_LEN(1) + __EXT4_DIR_REC_LEN(2)) {
 753                 EXT4_ERROR_INODE(inode, "invalid size");
 754                 return true;
 755         }
 756 diff --git a/fs/ext4/super.c b/fs/ext4/super.c
 757 index 1f1342f..33f7e88 100644
 758 --- a/fs/ext4/super.c
 759 +++ b/fs/ext4/super.c
 760 @@ -1445,7 +1445,7 @@ enum {
 761         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
 762         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 763         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
 764 -       Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
 765 +       Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err, Opt_dirdata,
 766         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
 767         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
 768         Opt_nowarn_on_error, Opt_mblk_io_submit,
 769 @@ -1521,6 +1521,7 @@ static const match_table_t tokens = {
 770         {Opt_nolazytime, "nolazytime"},
 771         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
 772         {Opt_nodelalloc, "nodelalloc"},
 773 +       {Opt_dirdata, "dirdata"},
 774         {Opt_removed, "mblk_io_submit"},
 775         {Opt_removed, "nomblk_io_submit"},
 776         {Opt_block_validity, "block_validity"},
 777 @@ -1744,6 +1745,7 @@ static const struct mount_opts {
 778         {Opt_usrjquota, 0, MOPT_Q},
 779         {Opt_grpjquota, 0, MOPT_Q},
 780         {Opt_offusrjquota, 0, MOPT_Q},
 781 +       {Opt_dirdata, EXT4_MOUNT_DIRDATA, MOPT_SET},
 782         {Opt_offgrpjquota, 0, MOPT_Q},
 783         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
 784         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},