ldiskfs/kernel_patches/patches/ubuntu18/ext4-data-in-dirent.patch

   1 commit 2db3b2b33ee796f4ea61316773452d936303ad27
   2 Author:     Pravin Shelar <Pravin.Shelar@sun.com>
   3 AuthorDate: Sun Oct 4 18:13:14 2009 +0000
   4 Subject: ext4: add ext4-data-in-dirent patch
   5
   6 Allows ext4 to store extra data records inside the ext4_dirent
   7 along with the regular directory entry (type, length, filename).
   8 Data is stored in ext4 dirent after filename, with a bit flag in
   9 de->file_type to indicate if any record after de->name is used.
  10 Each in-use record is variable length and must store a 1-byte
  11 length (including the length byte itself) at the start so that it
  12 can be skipped if the record type is unknown/uneeded.  The record
  13 starts after a NUL byte terminator for the filename.  This extra
  14 space is accounted in de->rec_len but not de->name_len.
  15
  16 Flag EXT4_DIRENT_LUFID is used for a 128-bit file identifier.
  17 Make use of dentry->d_fsdata to pass LUFID to ext4, so no changes
  18 in ext4_add_entry() interface are required.
  19
  20 Bugzilla-ID: b=17670
  21 Signed-off-by: Pravin Shelar <Pravin.Shelar@sun.com>
  22 Reviewed-by: Huang Hua <h.huang@sun.com>
  23 Signed-off-by: Andreas Dilger <andreas.dilger@sun.com>
  24
  25 Index: linux-4.15.0/fs/ext4/dir.c
  26 ===================================================================
  27 --- linux-4.15.0.orig/fs/ext4/dir.c
  28 +++ linux-4.15.0/fs/ext4/dir.c
  29 @@ -68,11 +68,11 @@ int __ext4_check_dir_entry(const char *f
  30         const int rlen = ext4_rec_len_from_disk(de->rec_len,
  31                                                 dir->i_sb->s_blocksize);
  32
  33 -       if (unlikely(rlen < EXT4_DIR_REC_LEN(1)))
  34 +       if (unlikely(rlen < __EXT4_DIR_REC_LEN(1)))
  35                 error_msg = "rec_len is smaller than minimal";
  36         else if (unlikely(rlen % 4 != 0))
  37                 error_msg = "rec_len % 4 != 0";
  38 -       else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len)))
  39 +       else if (unlikely(rlen < EXT4_DIR_REC_LEN(de)))
  40                 error_msg = "rec_len is too small for name_len";
  41         else if (unlikely(((char *) de - buf) + rlen > size))
  42                 error_msg = "directory entry across range";
  43 @@ -219,7 +219,7 @@ static int ext4_readdir(struct file *fil
  44                                  * failure will be detected in the
  45                                  * dirent test below. */
  46                                 if (ext4_rec_len_from_disk(de->rec_len,
  47 -                                       sb->s_blocksize) < EXT4_DIR_REC_LEN(1))
  48 +                                   sb->s_blocksize) < __EXT4_DIR_REC_LEN(1))
  49                                         break;
  50                                 i += ext4_rec_len_from_disk(de->rec_len,
  51                                                             sb->s_blocksize);
  52 @@ -442,12 +442,17 @@ int ext4_htree_store_dirent(struct file
  53         struct fname *fname, *new_fn;
  54         struct dir_private_info *info;
  55         int len;
  56 +       int extra_data = 0;
  57
  58         info = dir_file->private_data;
  59         p = &info->root.rb_node;
  60
  61         /* Create and allocate the fname structure */
  62 -       len = sizeof(struct fname) + ent_name->len + 1;
  63 +       if (dirent->file_type & EXT4_DIRENT_LUFID)
  64 +               extra_data = ext4_get_dirent_data_len(dirent);
  65 +
  66 +       len = sizeof(struct fname) + ent_name->len + extra_data + 1;
  67 +
  68         new_fn = kzalloc(len, GFP_KERNEL);
  69         if (!new_fn)
  70                 return -ENOMEM;
  71 @@ -456,7 +461,7 @@ int ext4_htree_store_dirent(struct file
  72         new_fn->inode = le32_to_cpu(dirent->inode);
  73         new_fn->name_len = ent_name->len;
  74         new_fn->file_type = dirent->file_type;
  75 -       memcpy(new_fn->name, ent_name->name, ent_name->len);
  76 +       memcpy(new_fn->name, ent_name->name, ent_name->len + extra_data);
  77         new_fn->name[ent_name->len] = 0;
  78
  79         while (*p) {
  80 Index: linux-4.15.0/fs/ext4/ext4.h
  81 ===================================================================
  82 --- linux-4.15.0.orig/fs/ext4/ext4.h
  83 +++ linux-4.15.0/fs/ext4/ext4.h
  84 @@ -1055,6 +1055,7 @@ struct ext4_inode_info {
  85         __u32 i_csum_seed;
  86
  87         kprojid_t i_projid;
  88 +       void *i_dirdata;
  89  };
  90
  91  /*
  92 @@ -1088,6 +1089,7 @@ struct ext4_inode_info {
  93   * Mount flags set via mount options or defaults
  94   */
  95  #define EXT4_MOUNT_NO_MBCACHE          0x00001 /* Do not use mbcache */
  96 +#define EXT4_MOUNT_DIRDATA             0x00002 /* Data in directory entries */
  97  #define EXT4_MOUNT_GRPID               0x00004 /* Create files with directory's group */
  98  #define EXT4_MOUNT_DEBUG               0x00008 /* Some debugging messages */
  99  #define EXT4_MOUNT_ERRORS_CONT         0x00010 /* Continue on errors */
 100 @@ -1768,6 +1770,7 @@ EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,              EN
 101                                          EXT4_FEATURE_INCOMPAT_FLEX_BG| \
 102                                          EXT4_FEATURE_INCOMPAT_EA_INODE| \
 103                                          EXT4_FEATURE_INCOMPAT_MMP | \
 104 +                                        EXT4_FEATURE_INCOMPAT_DIRDATA| \
 105                                          EXT4_FEATURE_INCOMPAT_INLINE_DATA | \
 106                                          EXT4_FEATURE_INCOMPAT_ENCRYPT | \
 107                                          EXT4_FEATURE_INCOMPAT_CSUM_SEED | \
 108 @@ -1943,6 +1946,43 @@ struct ext4_dir_entry_tail {
 109  #define EXT4_FT_SYMLINK                7
 110
 111  #define EXT4_FT_MAX            8
 112 +#define EXT4_FT_MASK           0xf
 113 +
 114 +#if EXT4_FT_MAX > EXT4_FT_MASK
 115 +#error "conflicting EXT4_FT_MAX and EXT4_FT_MASK"
 116 +#endif
 117 +
 118 +/*
 119 + * d_type has 4 unused bits, so it can hold four types data. these different
 120 + * type of data (e.g. lustre data, high 32 bits of 64-bit inode number) can be
 121 + * stored, in flag order, after file-name in ext4 dirent.
 122 +*/
 123 +/*
 124 + * this flag is added to d_type if ext4 dirent has extra data after
 125 + * filename. this data length is variable and length is stored in first byte
 126 + * of data. data start after filename NUL byte.
 127 + * This is used by Lustre FS.
 128 +  */
 129 +#define EXT4_DIRENT_LUFID              0x10
 130 +
 131 +#define EXT4_LUFID_MAGIC    0xAD200907UL
 132 +struct ext4_dentry_param {
 133 +       __u32  edp_magic;       /* EXT4_LUFID_MAGIC */
 134 +       char   edp_len;         /* size of edp_data in bytes */
 135 +       char   edp_data[0];     /* packed array of data */
 136 +} __packed;
 137 +
 138 +static inline unsigned char *ext4_dentry_get_data(struct super_block *sb,
 139 +                                                 struct ext4_dentry_param *p)
 140 +
 141 +{
 142 +       if (!ext4_has_feature_dirdata(sb))
 143 +               return NULL;
 144 +       if (p && p->edp_magic == EXT4_LUFID_MAGIC)
 145 +               return &p->edp_len;
 146 +       else
 147 +               return NULL;
 148 +}
 149
 150  #define EXT4_FT_DIR_CSUM       0xDE
 151
 152 @@ -1953,8 +1993,11 @@ struct ext4_dir_entry_tail {
 153   */
 154  #define EXT4_DIR_PAD                   4
 155  #define EXT4_DIR_ROUND                 (EXT4_DIR_PAD - 1)
 156 -#define EXT4_DIR_REC_LEN(name_len)     (((name_len) + 8 + EXT4_DIR_ROUND) & \
 157 +#define __EXT4_DIR_REC_LEN(name_len)   (((name_len) + 8 + EXT4_DIR_ROUND) & \
 158                                          ~EXT4_DIR_ROUND)
 159 +#define EXT4_DIR_REC_LEN(de)           (__EXT4_DIR_REC_LEN((de)->name_len +\
 160 +                                       ext4_get_dirent_data_len(de)))
 161 +
 162  #define EXT4_MAX_REC_LEN               ((1<<16)-1)
 163
 164  /*
 165 @@ -2357,11 +2400,11 @@ extern int ext4_find_dest_de(struct inod
 166                              struct buffer_head *bh,
 167                              void *buf, int buf_size,
 168                              struct ext4_filename *fname,
 169 -                            struct ext4_dir_entry_2 **dest_de);
 170 +                            struct ext4_dir_entry_2 **dest_de, int *dlen);
 171  void ext4_insert_dentry(struct inode *inode,
 172                         struct ext4_dir_entry_2 *de,
 173                         int buf_size,
 174 -                       struct ext4_filename *fname);
 175 +                       struct ext4_filename *fname, void *data);
 176  static inline void ext4_update_dx_flag(struct inode *inode)
 177  {
 178         if (!ext4_has_feature_dir_index(inode->i_sb))
 179 @@ -2373,10 +2416,17 @@ static const unsigned char ext4_filetype
 180
 181  static inline  unsigned char get_dtype(struct super_block *sb, int filetype)
 182  {
 183 -       if (!ext4_has_feature_filetype(sb) || filetype >= EXT4_FT_MAX)
 184 +       int fl_index = filetype & EXT4_FT_MASK;
 185 +
 186 +       if (!ext4_has_feature_filetype(sb) || fl_index >= EXT4_FT_MAX)
 187                 return DT_UNKNOWN;
 188
 189 -       return ext4_filetype_table[filetype];
 190 +       if (!test_opt(sb, DIRDATA))
 191 +               return ext4_filetype_table[fl_index];
 192 +
 193 +       return (ext4_filetype_table[fl_index]) |
 194 +               (filetype & EXT4_DIRENT_LUFID);
 195 +
 196  }
 197  extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh,
 198                              void *buf, int buf_size);
 199 @@ -2525,6 +2575,8 @@ extern struct inode *ext4_create_inode(h
 200  extern int ext4_delete_entry(handle_t *handle, struct inode * dir,
 201                              struct ext4_dir_entry_2 *de_del,
 202                              struct buffer_head *bh);
 203 +extern int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
 204 +                              struct inode *inode, const void *, const void *);
 205  extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 206                                 __u32 start_minor_hash, __u32 *next_hash);
 207  extern int ext4_search_dir(struct buffer_head *bh,
 208 @@ -3265,6 +3317,36 @@ static inline void ext4_clear_io_unwritt
 209
 210  extern const struct iomap_ops ext4_iomap_ops;
 211
 212 +/*
 213 + * Compute the total directory entry data length.
 214 + * This includes the filename and an implicit NUL terminator (always present),
 215 + * and optional extensions.  Each extension has a bit set in the high 4 bits of
 216 + * de->file_type, and the extension length is the first byte in each entry.
 217 + */
 218 +static inline int ext4_get_dirent_data_len(struct ext4_dir_entry_2 *de)
 219 +{
 220 +       char *len = de->name + de->name_len + 1 /* NUL terminator */;
 221 +       int dlen = 0;
 222 +       __u8 extra_data_flags = (de->file_type & ~EXT4_FT_MASK) >> 4;
 223 +       struct ext4_dir_entry_tail *t = (struct ext4_dir_entry_tail *)de;
 224 +
 225 +       if (!t->det_reserved_zero1 &&
 226 +           le16_to_cpu(t->det_rec_len) ==
 227 +               sizeof(struct ext4_dir_entry_tail) &&
 228 +           !t->det_reserved_zero2 &&
 229 +           t->det_reserved_ft == EXT4_FT_DIR_CSUM)
 230 +               return 0;
 231 +
 232 +       while (extra_data_flags) {
 233 +               if (extra_data_flags & 1) {
 234 +                       dlen += *len + (dlen == 0);
 235 +                       len += *len;
 236 +               }
 237 +               extra_data_flags >>= 1;
 238 +       }
 239 +       return dlen;
 240 +}
 241 +
 242  #endif /* __KERNEL__ */
 243
 244  #define EFSBADCRC      EBADMSG         /* Bad CRC detected */
 245 Index: linux-4.15.0/fs/ext4/namei.c
 246 ===================================================================
 247 --- linux-4.15.0.orig/fs/ext4/namei.c
 248 +++ linux-4.15.0/fs/ext4/namei.c
 249 @@ -242,7 +242,8 @@ static unsigned dx_get_count(struct dx_e
 250  static unsigned dx_get_limit(struct dx_entry *entries);
 251  static void dx_set_count(struct dx_entry *entries, unsigned value);
 252  static void dx_set_limit(struct dx_entry *entries, unsigned value);
 253 -static unsigned dx_root_limit(struct inode *dir, unsigned infosize);
 254 +static inline unsigned dx_root_limit(struct inode *dir,
 255 +               struct ext4_dir_entry_2 *dot_de, unsigned infosize);
 256  static unsigned dx_node_limit(struct inode *dir);
 257  static struct dx_frame *dx_probe(struct ext4_filename *fname,
 258                                  struct inode *dir,
 259 @@ -385,22 +386,23 @@ static struct dx_countlimit *get_dx_coun
 260  {
 261         struct ext4_dir_entry *dp;
 262         struct dx_root_info *root;
 263 -       int count_offset;
 264 +       int count_offset, dot_rec_len, dotdot_rec_len;
 265
 266         if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
 267                 count_offset = 8;
 268 -       else if (le16_to_cpu(dirent->rec_len) == 12) {
 269 -               dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
 270 +       else {
 271 +               dot_rec_len = le16_to_cpu(dirent->rec_len);
 272 +               dp = (struct ext4_dir_entry *)(((void *)dirent) + dot_rec_len);
 273                 if (le16_to_cpu(dp->rec_len) !=
 274 -                   EXT4_BLOCK_SIZE(inode->i_sb) - 12)
 275 +                   EXT4_BLOCK_SIZE(inode->i_sb) - dot_rec_len)
 276                         return NULL;
 277 -               root = (struct dx_root_info *)(((void *)dp + 12));
 278 +               dotdot_rec_len = EXT4_DIR_REC_LEN((struct ext4_dir_entry_2 *)dp);
 279 +               root = (struct dx_root_info *)(((void *)dp + dotdot_rec_len));
 280                 if (root->reserved_zero ||
 281                     root->info_length != sizeof(struct dx_root_info))
 282                         return NULL;
 283 -               count_offset = 32;
 284 -       } else
 285 -               return NULL;
 286 +               count_offset = 8 + dot_rec_len + dotdot_rec_len;
 287 +       }
 288
 289         if (offset)
 290                 *offset = count_offset;
 291 @@ -505,11 +506,12 @@ ext4_next_entry(struct ext4_dir_entry_2
 292   */
 293  struct dx_root_info *dx_get_dx_info(struct ext4_dir_entry_2 *de)
 294  {
 295 +       BUG_ON(de->name_len != 1);
 296         /* get dotdot first */
 297 -       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(1));
 298 +       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(de));
 299
 300         /* dx root info is after dotdot entry */
 301 -       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(2));
 302 +       de = (struct ext4_dir_entry_2 *)((char *)de + EXT4_DIR_REC_LEN(de));
 303
 304         return (struct dx_root_info *)de;
 305  }
 306 @@ -554,10 +556,16 @@ static inline void dx_set_limit(struct d
 307         ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
 308  }
 309
 310 -static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)
 311 +static inline unsigned dx_root_limit(struct inode *dir,
 312 +               struct ext4_dir_entry_2 *dot_de, unsigned infosize)
 313  {
 314 -       unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
 315 -               EXT4_DIR_REC_LEN(2) - infosize;
 316 +       struct ext4_dir_entry_2 *dotdot_de;
 317 +       unsigned entry_space;
 318 +
 319 +       BUG_ON(dot_de->name_len != 1);
 320 +       dotdot_de = ext4_next_entry(dot_de, dir->i_sb->s_blocksize);
 321 +       entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(dot_de) -
 322 +                        EXT4_DIR_REC_LEN(dotdot_de) - infosize;
 323
 324         if (ext4_has_metadata_csum(dir->i_sb))
 325                 entry_space -= sizeof(struct dx_tail);
 326 @@ -566,7 +574,7 @@ static inline unsigned dx_root_limit(str
 327
 328  static inline unsigned dx_node_limit(struct inode *dir)
 329  {
 330 -       unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
 331 +       unsigned entry_space = dir->i_sb->s_blocksize - __EXT4_DIR_REC_LEN(0);
 332
 333         if (ext4_has_metadata_csum(dir->i_sb))
 334                 entry_space -= sizeof(struct dx_tail);
 335 @@ -678,7 +686,7 @@ static struct stats dx_show_leaf(struct
 336                                        (unsigned) ((char *) de - base));
 337  #endif
 338                         }
 339 -                       space += EXT4_DIR_REC_LEN(de->name_len);
 340 +                       space += EXT4_DIR_REC_LEN(de);
 341                         names++;
 342                 }
 343                 de = ext4_next_entry(de, size);
 344 @@ -785,11 +793,14 @@ dx_probe(struct ext4_filename *fname, st
 345
 346         entries = (struct dx_entry *)(((char *)info) + info->info_length);
 347
 348 -       if (dx_get_limit(entries) != dx_root_limit(dir,
 349 -                                                  info->info_length)) {
 350 +       if (dx_get_limit(entries) !=
 351 +           dx_root_limit(dir, (struct ext4_dir_entry_2 *)frame->bh->b_data,
 352 +                         info->info_length)) {
 353                 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",
 354                                    dx_get_limit(entries),
 355 -                                  dx_root_limit(dir, info->info_length));
 356 +                                  dx_root_limit(dir,
 357 +                                         (struct ext4_dir_entry_2 *)frame->bh->b_data,
 358 +                                         info->info_length));
 359                 goto fail;
 360         }
 361
 362 @@ -981,7 +992,7 @@ static int htree_dirblock_to_tree(struct
 363         de = (struct ext4_dir_entry_2 *) bh->b_data;
 364         top = (struct ext4_dir_entry_2 *) ((char *) de +
 365                                            dir->i_sb->s_blocksize -
 366 -                                          EXT4_DIR_REC_LEN(0));
 367 +                                          __EXT4_DIR_REC_LEN(0));
 368  #ifdef CONFIG_EXT4_FS_ENCRYPTION
 369         /* Check if the directory is encrypted */
 370         if (ext4_encrypted_inode(dir)) {
 371 @@ -1653,7 +1664,7 @@ dx_move_dirents(char *from, char *to, st
 372         while (count--) {
 373                 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)
 374                                                 (from + (map->offs<<2));
 375 -               rec_len = EXT4_DIR_REC_LEN(de->name_len);
 376 +               rec_len = EXT4_DIR_REC_LEN(de);
 377                 memcpy (to, de, rec_len);
 378                 ((struct ext4_dir_entry_2 *) to)->rec_len =
 379                                 ext4_rec_len_to_disk(rec_len, blocksize);
 380 @@ -1677,7 +1688,7 @@ static struct ext4_dir_entry_2* dx_pack_
 381         while ((char*)de < base + blocksize) {
 382                 next = ext4_next_entry(de, blocksize);
 383                 if (de->inode && de->name_len) {
 384 -                       rec_len = EXT4_DIR_REC_LEN(de->name_len);
 385 +                       rec_len = EXT4_DIR_REC_LEN(de);
 386                         if (de > to)
 387                                 memmove(to, de, rec_len);
 388                         to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
 389 @@ -1808,14 +1819,16 @@ int ext4_find_dest_de(struct inode *dir,
 390                       struct buffer_head *bh,
 391                       void *buf, int buf_size,
 392                       struct ext4_filename *fname,
 393 -                     struct ext4_dir_entry_2 **dest_de)
 394 +                     struct ext4_dir_entry_2 **dest_de, int *dlen)
 395  {
 396         struct ext4_dir_entry_2 *de;
 397 -       unsigned short reclen = EXT4_DIR_REC_LEN(fname_len(fname));
 398 +       unsigned short reclen = __EXT4_DIR_REC_LEN(fname_len(fname)) +
 399 +                                                 (dlen ? *dlen : 0);
 400         int nlen, rlen;
 401         unsigned int offset = 0;
 402         char *top;
 403
 404 +       dlen ? *dlen = 0 : 0; /* default set to 0 */
 405         de = (struct ext4_dir_entry_2 *)buf;
 406         top = buf + buf_size - reclen;
 407         while ((char *) de <= top) {
 408 @@ -1824,10 +1837,26 @@ int ext4_find_dest_de(struct inode *dir,
 409                         return -EFSCORRUPTED;
 410                 if (ext4_match(fname, de))
 411                         return -EEXIST;
 412 -               nlen = EXT4_DIR_REC_LEN(de->name_len);
 413 +               nlen = EXT4_DIR_REC_LEN(de);
 414                 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 415                 if ((de->inode ? rlen - nlen : rlen) >= reclen)
 416                         break;
 417 +               /* Then for dotdot entries, check for the smaller space
 418 +                * required for just the entry, no FID */
 419 +               if (fname_len(fname) == 2 && memcmp(fname_name(fname), "..", 2) == 0) {
 420 +                       if ((de->inode ? rlen - nlen : rlen) >=
 421 +                           __EXT4_DIR_REC_LEN(fname_len(fname))) {
 422 +                               /* set dlen=1 to indicate not
 423 +                                * enough space store fid */
 424 +                               dlen ? *dlen = 1 : 0;
 425 +                               break;
 426 +                       }
 427 +                       /* The new ".." entry must be written over the
 428 +                        * previous ".." entry, which is the first
 429 +                        * entry traversed by this scan. If it doesn't
 430 +                        * fit, something is badly wrong, so -EIO. */
 431 +                       return -EIO;
 432 +               }
 433                 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
 434                 offset += rlen;
 435         }
 436 @@ -1841,12 +1870,12 @@ int ext4_find_dest_de(struct inode *dir,
 437  void ext4_insert_dentry(struct inode *inode,
 438                         struct ext4_dir_entry_2 *de,
 439                         int buf_size,
 440 -                       struct ext4_filename *fname)
 441 +                       struct ext4_filename *fname, void *data)
 442  {
 443
 444         int nlen, rlen;
 445
 446 -       nlen = EXT4_DIR_REC_LEN(de->name_len);
 447 +       nlen = EXT4_DIR_REC_LEN(de);
 448         rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);
 449         if (de->inode) {
 450                 struct ext4_dir_entry_2 *de1 =
 451 @@ -1860,6 +1889,11 @@ void ext4_insert_dentry(struct inode *in
 452         ext4_set_de_type(inode->i_sb, de, inode->i_mode);
 453         de->name_len = fname_len(fname);
 454         memcpy(de->name, fname_name(fname), fname_len(fname));
 455 +       if (data) {
 456 +               de->name[fname_len(fname)] = 0;
 457 +               memcpy(&de->name[fname_len(fname) + 1], data, *(char *)data);
 458 +               de->file_type |= EXT4_DIRENT_LUFID;
 459 +       }
 460  }
 461
 462  /*
 463 @@ -1877,14 +1911,19 @@ static int add_dirent_to_buf(handle_t *h
 464  {
 465         unsigned int    blocksize = dir->i_sb->s_blocksize;
 466         int             csum_size = 0;
 467 -       int             err;
 468 +       int             err, dlen = 0;
 469 +       unsigned char   *data;
 470
 471 +       data = ext4_dentry_get_data(inode->i_sb, (struct ext4_dentry_param *)
 472 +                                               EXT4_I(inode)->i_dirdata);
 473         if (ext4_has_metadata_csum(inode->i_sb))
 474                 csum_size = sizeof(struct ext4_dir_entry_tail);
 475
 476         if (!de) {
 477 +               if (data)
 478 +                       dlen = (*data) + 1;
 479                 err = ext4_find_dest_de(dir, inode, bh, bh->b_data,
 480 -                                       blocksize - csum_size, fname, &de);
 481 +                                       blocksize - csum_size, fname, &de, &dlen);
 482                 if (err)
 483                         return err;
 484         }
 485 @@ -1896,7 +1935,10 @@ static int add_dirent_to_buf(handle_t *h
 486         }
 487
 488         /* By now the buffer is marked for journaling */
 489 -       ext4_insert_dentry(inode, de, blocksize, fname);
 490 +       /* If writing the short form of "dotdot", don't add the data section */
 491 +       if (dlen == 1)
 492 +               data = NULL;
 493 +       ext4_insert_dentry(inode, de, blocksize, fname, data);
 494
 495         /*
 496          * XXX shouldn't update any times until successful
 497 @@ -2005,7 +2047,8 @@ static int make_indexed_dir(handle_t *ha
 498
 499         dx_set_block(entries, 1);
 500         dx_set_count(entries, 1);
 501 -       dx_set_limit(entries, dx_root_limit(dir, sizeof(*dx_info)));
 502 +       dx_set_limit(entries, dx_root_limit(dir,
 503 +                                        dot_de, sizeof(*dx_info)));
 504
 505         /* Initialize as for dx_probe */
 506         fname->hinfo.hash_version = dx_info->hash_version;
 507 @@ -2055,6 +2098,8 @@ static int ext4_update_dotdot(handle_t *
 508         struct buffer_head *dir_block;
 509         struct ext4_dir_entry_2 *de;
 510         int len, journal = 0, err = 0;
 511 +       int dlen = 0;
 512 +       char *data;
 513
 514         if (IS_ERR(handle))
 515                 return PTR_ERR(handle);
 516 @@ -2072,19 +2117,24 @@ static int ext4_update_dotdot(handle_t *
 517         /* the first item must be "." */
 518         assert(de->name_len == 1 && de->name[0] == '.');
 519         len = le16_to_cpu(de->rec_len);
 520 -       assert(len >= EXT4_DIR_REC_LEN(1));
 521 -       if (len > EXT4_DIR_REC_LEN(1)) {
 522 +       assert(len >= __EXT4_DIR_REC_LEN(1));
 523 +       if (len > __EXT4_DIR_REC_LEN(1)) {
 524                 BUFFER_TRACE(dir_block, "get_write_access");
 525                 err = ext4_journal_get_write_access(handle, dir_block);
 526                 if (err)
 527                         goto out_journal;
 528
 529                 journal = 1;
 530 -               de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(1));
 531 +               de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de));
 532         }
 533
 534 -       len -= EXT4_DIR_REC_LEN(1);
 535 -       assert(len == 0 || len >= EXT4_DIR_REC_LEN(2));
 536 +       len -= EXT4_DIR_REC_LEN(de);
 537 +       data = ext4_dentry_get_data(dir->i_sb,
 538 +                       (struct ext4_dentry_param *)dentry->d_fsdata);
 539 +       if (data)
 540 +               dlen = *data + 1;
 541 +       assert(len == 0 || len >= __EXT4_DIR_REC_LEN(2 + dlen));
 542 +
 543         de = (struct ext4_dir_entry_2 *)
 544                         ((char *) de + le16_to_cpu(de->rec_len));
 545         if (!journal) {
 546 @@ -2098,10 +2148,15 @@ static int ext4_update_dotdot(handle_t *
 547         if (len > 0)
 548                 de->rec_len = cpu_to_le16(len);
 549         else
 550 -               assert(le16_to_cpu(de->rec_len) >= EXT4_DIR_REC_LEN(2));
 551 +               assert(le16_to_cpu(de->rec_len) >= __EXT4_DIR_REC_LEN(2));
 552         de->name_len = 2;
 553         strcpy(de->name, "..");
 554 -       ext4_set_de_type(dir->i_sb, de, S_IFDIR);
 555 +       if (data != NULL && ext4_get_dirent_data_len(de) >= dlen) {
 556 +               de->name[2] = 0;
 557 +               memcpy(&de->name[2 + 1], data, *data);
 558 +               ext4_set_de_type(dir->i_sb, de, S_IFDIR);
 559 +               de->file_type |= EXT4_DIRENT_LUFID;
 560 +       }
 561
 562  out_journal:
 563         if (journal) {
 564 @@ -2140,6 +2195,7 @@ static int ext4_add_entry(handle_t *hand
 565         ext4_lblk_t block, blocks;
 566         int     csum_size = 0;
 567
 568 +       EXT4_I(inode)->i_dirdata = dentry->d_fsdata;
 569         if (ext4_has_metadata_csum(inode->i_sb))
 570                 csum_size = sizeof(struct ext4_dir_entry_tail);
 571
 572 @@ -2661,37 +2717,70 @@ err_unlock_inode:
 573         return err;
 574  }
 575
 576 +struct tp_block {
 577 +       struct inode *inode;
 578 +       void *data1;
 579 +       void *data2;
 580 +};
 581 +
 582  struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
 583                           struct ext4_dir_entry_2 *de,
 584                           int blocksize, int csum_size,
 585                           unsigned int parent_ino, int dotdot_real_len)
 586  {
 587 +       void *data1 = NULL, *data2 = NULL;
 588 +       int dot_reclen = 0;
 589 +
 590 +       if (dotdot_real_len == 10) {
 591 +               struct tp_block *tpb = (struct tp_block *)inode;
 592 +               data1 = tpb->data1;
 593 +               data2 = tpb->data2;
 594 +               inode = tpb->inode;
 595 +               dotdot_real_len = 0;
 596 +       }
 597         de->inode = cpu_to_le32(inode->i_ino);
 598         de->name_len = 1;
 599 -       de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
 600 -                                          blocksize);
 601         strcpy(de->name, ".");
 602         ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 603
 604 +       /* get packed fid data*/
 605 +       data1 = ext4_dentry_get_data(inode->i_sb,
 606 +                               (struct ext4_dentry_param *) data1);
 607 +       if (data1) {
 608 +               de->name[1] = 0;
 609 +               memcpy(&de->name[2], data1, *(char *) data1);
 610 +               de->file_type |= EXT4_DIRENT_LUFID;
 611 +       }
 612 +       de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de));
 613 +       dot_reclen = cpu_to_le16(de->rec_len);
 614         de = ext4_next_entry(de, blocksize);
 615         de->inode = cpu_to_le32(parent_ino);
 616         de->name_len = 2;
 617 +       strcpy(de->name, "..");
 618 +       ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 619 +       data2 = ext4_dentry_get_data(inode->i_sb,
 620 +                       (struct ext4_dentry_param *) data2);
 621 +       if (data2) {
 622 +               de->name[2] = 0;
 623 +               memcpy(&de->name[3], data2, *(char *) data2);
 624 +               de->file_type |= EXT4_DIRENT_LUFID;
 625 +       }
 626         if (!dotdot_real_len)
 627                 de->rec_len = ext4_rec_len_to_disk(blocksize -
 628 -                                       (csum_size + EXT4_DIR_REC_LEN(1)),
 629 +                                       (csum_size + dot_reclen),
 630                                         blocksize);
 631         else
 632                 de->rec_len = ext4_rec_len_to_disk(
 633 -                               EXT4_DIR_REC_LEN(de->name_len), blocksize);
 634 -       strcpy(de->name, "..");
 635 -       ext4_set_de_type(inode->i_sb, de, S_IFDIR);
 636 +                               EXT4_DIR_REC_LEN(de), blocksize);
 637
 638         return ext4_next_entry(de, blocksize);
 639  }
 640
 641  static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 642 -                            struct inode *inode)
 643 +                            struct inode *inode,
 644 +                            const void *data1, const void *data2)
 645  {
 646 +       struct tp_block param;
 647         struct buffer_head *dir_block = NULL;
 648         struct ext4_dir_entry_2 *de;
 649         struct ext4_dir_entry_tail *t;
 650 @@ -2716,7 +2805,11 @@ static int ext4_init_new_dir(handle_t *h
 651         if (IS_ERR(dir_block))
 652                 return PTR_ERR(dir_block);
 653         de = (struct ext4_dir_entry_2 *)dir_block->b_data;
 654 -       ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);
 655 +       param.inode = inode;
 656 +       param.data1 = (void *)data1;
 657 +       param.data2 = (void *)data2;
 658 +       ext4_init_dot_dotdot((struct inode *)(&param), de, blocksize,
 659 +                            csum_size, dir->i_ino, 10);
 660         set_nlink(inode, 2);
 661         if (csum_size) {
 662                 t = EXT4_DIRENT_TAIL(dir_block->b_data, blocksize);
 663 @@ -2733,6 +2826,29 @@ out:
 664         return err;
 665  }
 666
 667 +/* Initialize @inode as a subdirectory of @dir, and add the
 668 + * "." and ".." entries into the first directory block. */
 669 +int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
 670 +                       struct inode *inode,
 671 +                       const void *data1, const void *data2)
 672 +{
 673 +       int rc;
 674 +
 675 +       if (IS_ERR(handle))
 676 +               return PTR_ERR(handle);
 677 +
 678 +       if (IS_DIRSYNC(dir))
 679 +               ext4_handle_sync(handle);
 680 +
 681 +       inode->i_op = &ext4_dir_inode_operations;
 682 +       inode->i_fop = &ext4_dir_operations;
 683 +       rc = ext4_init_new_dir(handle, dir, inode, data1, data2);
 684 +       if (!rc)
 685 +               rc = ext4_mark_inode_dirty(handle, inode);
 686 +       return rc;
 687 +}
 688 +EXPORT_SYMBOL(ext4_add_dot_dotdot);
 689 +
 690  static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 691  {
 692         handle_t *handle;
 693 @@ -2759,7 +2875,7 @@ retry:
 694
 695         inode->i_op = &ext4_dir_inode_operations;
 696         inode->i_fop = &ext4_dir_operations;
 697 -       err = ext4_init_new_dir(handle, dir, inode);
 698 +       err = ext4_init_new_dir(handle, dir, inode, NULL, NULL);
 699         if (err)
 700                 goto out_clear_inode;
 701         err = ext4_mark_inode_dirty(handle, inode);
 702 @@ -2811,7 +2927,7 @@ bool ext4_empty_dir(struct inode *inode)
 703         }
 704
 705         sb = inode->i_sb;
 706 -       if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
 707 +       if (inode->i_size < __EXT4_DIR_REC_LEN(1) + __EXT4_DIR_REC_LEN(2)) {
 708                 EXT4_ERROR_INODE(inode, "invalid size");
 709                 return true;
 710         }
 711 Index: linux-4.15.0/fs/ext4/inline.c
 712 ===================================================================
 713 --- linux-4.15.0.orig/fs/ext4/inline.c
 714 +++ linux-4.15.0/fs/ext4/inline.c
 715 @@ -1017,7 +1017,7 @@ static int ext4_add_dirent_to_inline(han
 716         struct ext4_dir_entry_2 *de;
 717
 718         err = ext4_find_dest_de(dir, inode, iloc->bh, inline_start,
 719 -                               inline_size, fname, &de);
 720 +                               inline_size, fname, &de, NULL);
 721         if (err)
 722                 return err;
 723
 724 @@ -1025,7 +1025,7 @@ static int ext4_add_dirent_to_inline(han
 725         err = ext4_journal_get_write_access(handle, iloc->bh);
 726         if (err)
 727                 return err;
 728 -       ext4_insert_dentry(inode, de, inline_size, fname);
 729 +       ext4_insert_dentry(inode, de, inline_size, fname, NULL);
 730
 731         ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
 732
 733 @@ -1094,7 +1094,7 @@ static int ext4_update_inline_dir(handle
 734         int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
 735         int new_size = get_max_inline_xattr_value_size(dir, iloc);
 736
 737 -       if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
 738 +       if (new_size - old_size <= __EXT4_DIR_REC_LEN(1))
 739                 return -ENOSPC;
 740
 741         ret = ext4_update_inline_data(handle, dir,
 742 @@ -1375,7 +1375,7 @@ int htree_inlinedir_to_tree(struct file
 743                         fake.name_len = 1;
 744                         strcpy(fake.name, ".");
 745                         fake.rec_len = ext4_rec_len_to_disk(
 746 -                                               EXT4_DIR_REC_LEN(fake.name_len),
 747 +                                               EXT4_DIR_REC_LEN(&fake),
 748                                                 inline_size);
 749                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 750                         de = &fake;
 751 @@ -1385,7 +1385,7 @@ int htree_inlinedir_to_tree(struct file
 752                         fake.name_len = 2;
 753                         strcpy(fake.name, "..");
 754                         fake.rec_len = ext4_rec_len_to_disk(
 755 -                                               EXT4_DIR_REC_LEN(fake.name_len),
 756 +                                               EXT4_DIR_REC_LEN(&fake),
 757                                                 inline_size);
 758                         ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
 759                         de = &fake;
 760 @@ -1483,8 +1483,8 @@ int ext4_read_inline_dir(struct file *fi
 761          * So we will use extra_offset and extra_size to indicate them
 762          * during the inline dir iteration.
 763          */
 764 -       dotdot_offset = EXT4_DIR_REC_LEN(1);
 765 -       dotdot_size = dotdot_offset + EXT4_DIR_REC_LEN(2);
 766 +       dotdot_offset = __EXT4_DIR_REC_LEN(1);
 767 +       dotdot_size = dotdot_offset + __EXT4_DIR_REC_LEN(2);
 768         extra_offset = dotdot_size - EXT4_INLINE_DOTDOT_SIZE;
 769         extra_size = extra_offset + inline_size;
 770
 771 @@ -1519,7 +1519,7 @@ int ext4_read_inline_dir(struct file *fi
 772                          * failure will be detected in the
 773                          * dirent test below. */
 774                         if (ext4_rec_len_from_disk(de->rec_len, extra_size)
 775 -                               < EXT4_DIR_REC_LEN(1))
 776 +                               < __EXT4_DIR_REC_LEN(1))
 777                                 break;
 778                         i += ext4_rec_len_from_disk(de->rec_len,
 779                                                     extra_size);
 780 Index: linux-4.15.0/fs/ext4/super.c
 781 ===================================================================
 782 --- linux-4.15.0.orig/fs/ext4/super.c
 783 +++ linux-4.15.0/fs/ext4/super.c
 784 @@ -1347,7 +1347,7 @@ enum {
 785         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
 786         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 787         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
 788 -       Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
 789 +       Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err, Opt_dirdata,
 790         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
 791         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
 792         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
 793 @@ -1420,6 +1420,7 @@ static const match_table_t tokens = {
 794         {Opt_nolazytime, "nolazytime"},
 795         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
 796         {Opt_nodelalloc, "nodelalloc"},
 797 +       {Opt_dirdata, "dirdata"},
 798         {Opt_removed, "mblk_io_submit"},
 799         {Opt_removed, "nomblk_io_submit"},
 800         {Opt_block_validity, "block_validity"},
 801 @@ -1641,6 +1642,7 @@ static const struct mount_opts {
 802         {Opt_usrjquota, 0, MOPT_Q},
 803         {Opt_grpjquota, 0, MOPT_Q},
 804         {Opt_offusrjquota, 0, MOPT_Q},
 805 +       {Opt_dirdata, EXT4_MOUNT_DIRDATA, MOPT_SET},
 806         {Opt_offgrpjquota, 0, MOPT_Q},
 807         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
 808         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},