Pileus Git - ~andy/linux/blob - fs/ext4/inline.c

   1 /*
   2  * Copyright (c) 2012 Taobao.
   3  * Written by Tao Ma <boyu.mt@taobao.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2.1 of the GNU Lesser General Public License
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14 #include "ext4_jbd2.h"
  15 #include "ext4.h"
  16 #include "xattr.h"
  17 #include "truncate.h"
  18 #include <linux/fiemap.h>
  19
  20 #define EXT4_XATTR_SYSTEM_DATA  "data"
  21 #define EXT4_MIN_INLINE_DATA_SIZE       ((sizeof(__le32) * EXT4_N_BLOCKS))
  22 #define EXT4_INLINE_DOTDOT_SIZE 4
  23
  24 int ext4_get_inline_size(struct inode *inode)
  25 {
  26         if (EXT4_I(inode)->i_inline_off)
  27                 return EXT4_I(inode)->i_inline_size;
  28
  29         return 0;
  30 }
  31
  32 static int get_max_inline_xattr_value_size(struct inode *inode,
  33                                            struct ext4_iloc *iloc)
  34 {
  35         struct ext4_xattr_ibody_header *header;
  36         struct ext4_xattr_entry *entry;
  37         struct ext4_inode *raw_inode;
  38         int free, min_offs;
  39
  40         min_offs = EXT4_SB(inode->i_sb)->s_inode_size -
  41                         EXT4_GOOD_OLD_INODE_SIZE -
  42                         EXT4_I(inode)->i_extra_isize -
  43                         sizeof(struct ext4_xattr_ibody_header);
  44
  45         /*
  46          * We need to subtract another sizeof(__u32) since an in-inode xattr
  47          * needs an empty 4 bytes to indicate the gap between the xattr entry
  48          * and the name/value pair.
  49          */
  50         if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
  51                 return EXT4_XATTR_SIZE(min_offs -
  52                         EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA)) -
  53                         EXT4_XATTR_ROUND - sizeof(__u32));
  54
  55         raw_inode = ext4_raw_inode(iloc);
  56         header = IHDR(inode, raw_inode);
  57         entry = IFIRST(header);
  58
  59         /* Compute min_offs. */
  60         for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
  61                 if (!entry->e_value_block && entry->e_value_size) {
  62                         size_t offs = le16_to_cpu(entry->e_value_offs);
  63                         if (offs < min_offs)
  64                                 min_offs = offs;
  65                 }
  66         }
  67         free = min_offs -
  68                 ((void *)entry - (void *)IFIRST(header)) - sizeof(__u32);
  69
  70         if (EXT4_I(inode)->i_inline_off) {
  71                 entry = (struct ext4_xattr_entry *)
  72                         ((void *)raw_inode + EXT4_I(inode)->i_inline_off);
  73
  74                 free += le32_to_cpu(entry->e_value_size);
  75                 goto out;
  76         }
  77
  78         free -= EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA));
  79
  80         if (free > EXT4_XATTR_ROUND)
  81                 free = EXT4_XATTR_SIZE(free - EXT4_XATTR_ROUND);
  82         else
  83                 free = 0;
  84
  85 out:
  86         return free;
  87 }
  88
  89 /*
  90  * Get the maximum size we now can store in an inode.
  91  * If we can't find the space for a xattr entry, don't use the space
  92  * of the extents since we have no space to indicate the inline data.
  93  */
  94 int ext4_get_max_inline_size(struct inode *inode)
  95 {
  96         int error, max_inline_size;
  97         struct ext4_iloc iloc;
  98
  99         if (EXT4_I(inode)->i_extra_isize == 0)
 100                 return 0;
 101
 102         error = ext4_get_inode_loc(inode, &iloc);
 103         if (error) {
 104                 ext4_error_inode(inode, __func__, __LINE__, 0,
 105                                  "can't get inode location %lu",
 106                                  inode->i_ino);
 107                 return 0;
 108         }
 109
 110         down_read(&EXT4_I(inode)->xattr_sem);
 111         max_inline_size = get_max_inline_xattr_value_size(inode, &iloc);
 112         up_read(&EXT4_I(inode)->xattr_sem);
 113
 114         brelse(iloc.bh);
 115
 116         if (!max_inline_size)
 117                 return 0;
 118
 119         return max_inline_size + EXT4_MIN_INLINE_DATA_SIZE;
 120 }
 121
 122 int ext4_has_inline_data(struct inode *inode)
 123 {
 124         return ext4_test_inode_flag(inode, EXT4_INODE_INLINE_DATA) &&
 125                EXT4_I(inode)->i_inline_off;
 126 }
 127
 128 /*
 129  * this function does not take xattr_sem, which is OK because it is
 130  * currently only used in a code path coming form ext4_iget, before
 131  * the new inode has been unlocked
 132  */
 133 int ext4_find_inline_data_nolock(struct inode *inode)
 134 {
 135         struct ext4_xattr_ibody_find is = {
 136                 .s = { .not_found = -ENODATA, },
 137         };
 138         struct ext4_xattr_info i = {
 139                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
 140                 .name = EXT4_XATTR_SYSTEM_DATA,
 141         };
 142         int error;
 143
 144         if (EXT4_I(inode)->i_extra_isize == 0)
 145                 return 0;
 146
 147         error = ext4_get_inode_loc(inode, &is.iloc);
 148         if (error)
 149                 return error;
 150
 151         error = ext4_xattr_ibody_find(inode, &i, &is);
 152         if (error)
 153                 goto out;
 154
 155         if (!is.s.not_found) {
 156                 EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
 157                                         (void *)ext4_raw_inode(&is.iloc));
 158                 EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
 159                                 le32_to_cpu(is.s.here->e_value_size);
 160                 ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 161         }
 162 out:
 163         brelse(is.iloc.bh);
 164         return error;
 165 }
 166
 167 static int ext4_read_inline_data(struct inode *inode, void *buffer,
 168                                  unsigned int len,
 169                                  struct ext4_iloc *iloc)
 170 {
 171         struct ext4_xattr_entry *entry;
 172         struct ext4_xattr_ibody_header *header;
 173         int cp_len = 0;
 174         struct ext4_inode *raw_inode;
 175
 176         if (!len)
 177                 return 0;
 178
 179         BUG_ON(len > EXT4_I(inode)->i_inline_size);
 180
 181         cp_len = len < EXT4_MIN_INLINE_DATA_SIZE ?
 182                         len : EXT4_MIN_INLINE_DATA_SIZE;
 183
 184         raw_inode = ext4_raw_inode(iloc);
 185         memcpy(buffer, (void *)(raw_inode->i_block), cp_len);
 186
 187         len -= cp_len;
 188         buffer += cp_len;
 189
 190         if (!len)
 191                 goto out;
 192
 193         header = IHDR(inode, raw_inode);
 194         entry = (struct ext4_xattr_entry *)((void *)raw_inode +
 195                                             EXT4_I(inode)->i_inline_off);
 196         len = min_t(unsigned int, len,
 197                     (unsigned int)le32_to_cpu(entry->e_value_size));
 198
 199         memcpy(buffer,
 200                (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs), len);
 201         cp_len += len;
 202
 203 out:
 204         return cp_len;
 205 }
 206
 207 /*
 208  * write the buffer to the inline inode.
 209  * If 'create' is set, we don't need to do the extra copy in the xattr
 210  * value since it is already handled by ext4_xattr_ibody_inline_set.
 211  * That saves us one memcpy.
 212  */
 213 void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
 214                             void *buffer, loff_t pos, unsigned int len)
 215 {
 216         struct ext4_xattr_entry *entry;
 217         struct ext4_xattr_ibody_header *header;
 218         struct ext4_inode *raw_inode;
 219         int cp_len = 0;
 220
 221         BUG_ON(!EXT4_I(inode)->i_inline_off);
 222         BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
 223
 224         raw_inode = ext4_raw_inode(iloc);
 225         buffer += pos;
 226
 227         if (pos < EXT4_MIN_INLINE_DATA_SIZE) {
 228                 cp_len = pos + len > EXT4_MIN_INLINE_DATA_SIZE ?
 229                          EXT4_MIN_INLINE_DATA_SIZE - pos : len;
 230                 memcpy((void *)raw_inode->i_block + pos, buffer, cp_len);
 231
 232                 len -= cp_len;
 233                 buffer += cp_len;
 234                 pos += cp_len;
 235         }
 236
 237         if (!len)
 238                 return;
 239
 240         pos -= EXT4_MIN_INLINE_DATA_SIZE;
 241         header = IHDR(inode, raw_inode);
 242         entry = (struct ext4_xattr_entry *)((void *)raw_inode +
 243                                             EXT4_I(inode)->i_inline_off);
 244
 245         memcpy((void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs) + pos,
 246                buffer, len);
 247 }
 248
 249 static int ext4_create_inline_data(handle_t *handle,
 250                                    struct inode *inode, unsigned len)
 251 {
 252         int error;
 253         void *value = NULL;
 254         struct ext4_xattr_ibody_find is = {
 255                 .s = { .not_found = -ENODATA, },
 256         };
 257         struct ext4_xattr_info i = {
 258                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
 259                 .name = EXT4_XATTR_SYSTEM_DATA,
 260         };
 261
 262         error = ext4_get_inode_loc(inode, &is.iloc);
 263         if (error)
 264                 return error;
 265
 266         error = ext4_journal_get_write_access(handle, is.iloc.bh);
 267         if (error)
 268                 goto out;
 269
 270         if (len > EXT4_MIN_INLINE_DATA_SIZE) {
 271                 value = EXT4_ZERO_XATTR_VALUE;
 272                 len -= EXT4_MIN_INLINE_DATA_SIZE;
 273         } else {
 274                 value = "";
 275                 len = 0;
 276         }
 277
 278         /* Insert the the xttr entry. */
 279         i.value = value;
 280         i.value_len = len;
 281
 282         error = ext4_xattr_ibody_find(inode, &i, &is);
 283         if (error)
 284                 goto out;
 285
 286         BUG_ON(!is.s.not_found);
 287
 288         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 289         if (error) {
 290                 if (error == -ENOSPC)
 291                         ext4_clear_inode_state(inode,
 292                                                EXT4_STATE_MAY_INLINE_DATA);
 293                 goto out;
 294         }
 295
 296         memset((void *)ext4_raw_inode(&is.iloc)->i_block,
 297                 0, EXT4_MIN_INLINE_DATA_SIZE);
 298
 299         EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
 300                                       (void *)ext4_raw_inode(&is.iloc));
 301         EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
 302         ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
 303         ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
 304         get_bh(is.iloc.bh);
 305         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
 306
 307 out:
 308         brelse(is.iloc.bh);
 309         return error;
 310 }
 311
 312 static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
 313                                    unsigned int len)
 314 {
 315         int error;
 316         void *value = NULL;
 317         struct ext4_xattr_ibody_find is = {
 318                 .s = { .not_found = -ENODATA, },
 319         };
 320         struct ext4_xattr_info i = {
 321                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
 322                 .name = EXT4_XATTR_SYSTEM_DATA,
 323         };
 324
 325         /* If the old space is ok, write the data directly. */
 326         if (len <= EXT4_I(inode)->i_inline_size)
 327                 return 0;
 328
 329         error = ext4_get_inode_loc(inode, &is.iloc);
 330         if (error)
 331                 return error;
 332
 333         error = ext4_xattr_ibody_find(inode, &i, &is);
 334         if (error)
 335                 goto out;
 336
 337         BUG_ON(is.s.not_found);
 338
 339         len -= EXT4_MIN_INLINE_DATA_SIZE;
 340         value = kzalloc(len, GFP_NOFS);
 341         if (!value)
 342                 goto out;
 343
 344         error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
 345                                      value, len);
 346         if (error == -ENODATA)
 347                 goto out;
 348
 349         error = ext4_journal_get_write_access(handle, is.iloc.bh);
 350         if (error)
 351                 goto out;
 352
 353         /* Update the xttr entry. */
 354         i.value = value;
 355         i.value_len = len;
 356
 357         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 358         if (error)
 359                 goto out;
 360
 361         EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
 362                                       (void *)ext4_raw_inode(&is.iloc));
 363         EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
 364                                 le32_to_cpu(is.s.here->e_value_size);
 365         ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 366         get_bh(is.iloc.bh);
 367         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
 368
 369 out:
 370         kfree(value);
 371         brelse(is.iloc.bh);
 372         return error;
 373 }
 374
 375 int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
 376                              unsigned int len)
 377 {
 378         int ret, size;
 379         struct ext4_inode_info *ei = EXT4_I(inode);
 380
 381         if (!ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
 382                 return -ENOSPC;
 383
 384         size = ext4_get_max_inline_size(inode);
 385         if (size < len)
 386                 return -ENOSPC;
 387
 388         down_write(&EXT4_I(inode)->xattr_sem);
 389
 390         if (ei->i_inline_off)
 391                 ret = ext4_update_inline_data(handle, inode, len);
 392         else
 393                 ret = ext4_create_inline_data(handle, inode, len);
 394
 395         up_write(&EXT4_I(inode)->xattr_sem);
 396
 397         return ret;
 398 }
 399
 400 static int ext4_destroy_inline_data_nolock(handle_t *handle,
 401                                            struct inode *inode)
 402 {
 403         struct ext4_inode_info *ei = EXT4_I(inode);
 404         struct ext4_xattr_ibody_find is = {
 405                 .s = { .not_found = 0, },
 406         };
 407         struct ext4_xattr_info i = {
 408                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
 409                 .name = EXT4_XATTR_SYSTEM_DATA,
 410                 .value = NULL,
 411                 .value_len = 0,
 412         };
 413         int error;
 414
 415         if (!ei->i_inline_off)
 416                 return 0;
 417
 418         error = ext4_get_inode_loc(inode, &is.iloc);
 419         if (error)
 420                 return error;
 421
 422         error = ext4_xattr_ibody_find(inode, &i, &is);
 423         if (error)
 424                 goto out;
 425
 426         error = ext4_journal_get_write_access(handle, is.iloc.bh);
 427         if (error)
 428                 goto out;
 429
 430         error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
 431         if (error)
 432                 goto out;
 433
 434         memset((void *)ext4_raw_inode(&is.iloc)->i_block,
 435                 0, EXT4_MIN_INLINE_DATA_SIZE);
 436
 437         if (EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
 438                                       EXT4_FEATURE_INCOMPAT_EXTENTS)) {
 439                 if (S_ISDIR(inode->i_mode) ||
 440                     S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)) {
 441                         ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
 442                         ext4_ext_tree_init(handle, inode);
 443                 }
 444         }
 445         ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
 446
 447         get_bh(is.iloc.bh);
 448         error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
 449
 450         EXT4_I(inode)->i_inline_off = 0;
 451         EXT4_I(inode)->i_inline_size = 0;
 452         ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 453 out:
 454         brelse(is.iloc.bh);
 455         if (error == -ENODATA)
 456                 error = 0;
 457         return error;
 458 }
 459
 460 static int ext4_read_inline_page(struct inode *inode, struct page *page)
 461 {
 462         void *kaddr;
 463         int ret = 0;
 464         size_t len;
 465         struct ext4_iloc iloc;
 466
 467         BUG_ON(!PageLocked(page));
 468         BUG_ON(!ext4_has_inline_data(inode));
 469         BUG_ON(page->index);
 470
 471         if (!EXT4_I(inode)->i_inline_off) {
 472                 ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
 473                              inode->i_ino);
 474                 goto out;
 475         }
 476
 477         ret = ext4_get_inode_loc(inode, &iloc);
 478         if (ret)
 479                 goto out;
 480
 481         len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
 482         kaddr = kmap_atomic(page);
 483         ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
 484         flush_dcache_page(page);
 485         kunmap_atomic(kaddr);
 486         zero_user_segment(page, len, PAGE_CACHE_SIZE);
 487         SetPageUptodate(page);
 488         brelse(iloc.bh);
 489
 490 out:
 491         return ret;
 492 }
 493
 494 int ext4_readpage_inline(struct inode *inode, struct page *page)
 495 {
 496         int ret = 0;
 497
 498         down_read(&EXT4_I(inode)->xattr_sem);
 499         if (!ext4_has_inline_data(inode)) {
 500                 up_read(&EXT4_I(inode)->xattr_sem);
 501                 return -EAGAIN;
 502         }
 503
 504         /*
 505          * Current inline data can only exist in the 1st page,
 506          * So for all the other pages, just set them uptodate.
 507          */
 508         if (!page->index)
 509                 ret = ext4_read_inline_page(inode, page);
 510         else if (!PageUptodate(page)) {
 511                 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
 512                 SetPageUptodate(page);
 513         }
 514
 515         up_read(&EXT4_I(inode)->xattr_sem);
 516
 517         unlock_page(page);
 518         return ret >= 0 ? 0 : ret;
 519 }
 520
 521 static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
 522                                               struct inode *inode,
 523                                               unsigned flags)
 524 {
 525         int ret, needed_blocks;
 526         handle_t *handle = NULL;
 527         int retries = 0, sem_held = 0;
 528         struct page *page = NULL;
 529         unsigned from, to;
 530         struct ext4_iloc iloc;
 531
 532         if (!ext4_has_inline_data(inode)) {
 533                 /*
 534                  * clear the flag so that no new write
 535                  * will trap here again.
 536                  */
 537                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 538                 return 0;
 539         }
 540
 541         needed_blocks = ext4_writepage_trans_blocks(inode);
 542
 543         ret = ext4_get_inode_loc(inode, &iloc);
 544         if (ret)
 545                 return ret;
 546
 547 retry:
 548         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
 549         if (IS_ERR(handle)) {
 550                 ret = PTR_ERR(handle);
 551                 handle = NULL;
 552                 goto out;
 553         }
 554
 555         /* We cannot recurse into the filesystem as the transaction is already
 556          * started */
 557         flags |= AOP_FLAG_NOFS;
 558
 559         page = grab_cache_page_write_begin(mapping, 0, flags);
 560         if (!page) {
 561                 ret = -ENOMEM;
 562                 goto out;
 563         }
 564
 565         down_write(&EXT4_I(inode)->xattr_sem);
 566         sem_held = 1;
 567         /* If some one has already done this for us, just exit. */
 568         if (!ext4_has_inline_data(inode)) {
 569                 ret = 0;
 570                 goto out;
 571         }
 572
 573         from = 0;
 574         to = ext4_get_inline_size(inode);
 575         if (!PageUptodate(page)) {
 576                 ret = ext4_read_inline_page(inode, page);
 577                 if (ret < 0)
 578                         goto out;
 579         }
 580
 581         ret = ext4_destroy_inline_data_nolock(handle, inode);
 582         if (ret)
 583                 goto out;
 584
 585         if (ext4_should_dioread_nolock(inode))
 586                 ret = __block_write_begin(page, from, to, ext4_get_block_write);
 587         else
 588                 ret = __block_write_begin(page, from, to, ext4_get_block);
 589
 590         if (!ret && ext4_should_journal_data(inode)) {
 591                 ret = ext4_walk_page_buffers(handle, page_buffers(page),
 592                                              from, to, NULL,
 593                                              do_journal_get_write_access);
 594         }
 595
 596         if (ret) {
 597                 unlock_page(page);
 598                 page_cache_release(page);
 599                 ext4_orphan_add(handle, inode);
 600                 up_write(&EXT4_I(inode)->xattr_sem);
 601                 sem_held = 0;
 602                 ext4_journal_stop(handle);
 603                 handle = NULL;
 604                 ext4_truncate_failed_write(inode);
 605                 /*
 606                  * If truncate failed early the inode might
 607                  * still be on the orphan list; we need to
 608                  * make sure the inode is removed from the
 609                  * orphan list in that case.
 610                  */
 611                 if (inode->i_nlink)
 612                         ext4_orphan_del(NULL, inode);
 613         }
 614
 615         if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
 616                 goto retry;
 617
 618         block_commit_write(page, from, to);
 619 out:
 620         if (page) {
 621                 unlock_page(page);
 622                 page_cache_release(page);
 623         }
 624         if (sem_held)
 625                 up_write(&EXT4_I(inode)->xattr_sem);
 626         if (handle)
 627                 ext4_journal_stop(handle);
 628         brelse(iloc.bh);
 629         return ret;
 630 }
 631
 632 /*
 633  * Try to write data in the inode.
 634  * If the inode has inline data, check whether the new write can be
 635  * in the inode also. If not, create the page the handle, move the data
 636  * to the page make it update and let the later codes create extent for it.
 637  */
 638 int ext4_try_to_write_inline_data(struct address_space *mapping,
 639                                   struct inode *inode,
 640                                   loff_t pos, unsigned len,
 641                                   unsigned flags,
 642                                   struct page **pagep)
 643 {
 644         int ret;
 645         handle_t *handle;
 646         struct page *page;
 647         struct ext4_iloc iloc;
 648
 649         if (pos + len > ext4_get_max_inline_size(inode))
 650                 goto convert;
 651
 652         ret = ext4_get_inode_loc(inode, &iloc);
 653         if (ret)
 654                 return ret;
 655
 656         /*
 657          * The possible write could happen in the inode,
 658          * so try to reserve the space in inode first.
 659          */
 660         handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 661         if (IS_ERR(handle)) {
 662                 ret = PTR_ERR(handle);
 663                 handle = NULL;
 664                 goto out;
 665         }
 666
 667         ret = ext4_prepare_inline_data(handle, inode, pos + len);
 668         if (ret && ret != -ENOSPC)
 669                 goto out;
 670
 671         /* We don't have space in inline inode, so convert it to extent. */
 672         if (ret == -ENOSPC) {
 673                 ext4_journal_stop(handle);
 674                 brelse(iloc.bh);
 675                 goto convert;
 676         }
 677
 678         flags |= AOP_FLAG_NOFS;
 679
 680         page = grab_cache_page_write_begin(mapping, 0, flags);
 681         if (!page) {
 682                 ret = -ENOMEM;
 683                 goto out;
 684         }
 685
 686         *pagep = page;
 687         down_read(&EXT4_I(inode)->xattr_sem);
 688         if (!ext4_has_inline_data(inode)) {
 689                 ret = 0;
 690                 unlock_page(page);
 691                 page_cache_release(page);
 692                 goto out_up_read;
 693         }
 694
 695         if (!PageUptodate(page)) {
 696                 ret = ext4_read_inline_page(inode, page);
 697                 if (ret < 0)
 698                         goto out_up_read;
 699         }
 700
 701         ret = 1;
 702         handle = NULL;
 703 out_up_read:
 704         up_read(&EXT4_I(inode)->xattr_sem);
 705 out:
 706         if (handle)
 707                 ext4_journal_stop(handle);
 708         brelse(iloc.bh);
 709         return ret;
 710 convert:
 711         return ext4_convert_inline_data_to_extent(mapping,
 712                                                   inode, flags);
 713 }
 714
 715 int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
 716                                unsigned copied, struct page *page)
 717 {
 718         int ret;
 719         void *kaddr;
 720         struct ext4_iloc iloc;
 721
 722         if (unlikely(copied < len)) {
 723                 if (!PageUptodate(page)) {
 724                         copied = 0;
 725                         goto out;
 726                 }
 727         }
 728
 729         ret = ext4_get_inode_loc(inode, &iloc);
 730         if (ret) {
 731                 ext4_std_error(inode->i_sb, ret);
 732                 copied = 0;
 733                 goto out;
 734         }
 735
 736         down_write(&EXT4_I(inode)->xattr_sem);
 737         BUG_ON(!ext4_has_inline_data(inode));
 738
 739         kaddr = kmap_atomic(page);
 740         ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
 741         kunmap_atomic(kaddr);
 742         SetPageUptodate(page);
 743         /* clear page dirty so that writepages wouldn't work for us. */
 744         ClearPageDirty(page);
 745
 746         up_write(&EXT4_I(inode)->xattr_sem);
 747         brelse(iloc.bh);
 748 out:
 749         return copied;
 750 }
 751
 752 struct buffer_head *
 753 ext4_journalled_write_inline_data(struct inode *inode,
 754                                   unsigned len,
 755                                   struct page *page)
 756 {
 757         int ret;
 758         void *kaddr;
 759         struct ext4_iloc iloc;
 760
 761         ret = ext4_get_inode_loc(inode, &iloc);
 762         if (ret) {
 763                 ext4_std_error(inode->i_sb, ret);
 764                 return NULL;
 765         }
 766
 767         down_write(&EXT4_I(inode)->xattr_sem);
 768         kaddr = kmap_atomic(page);
 769         ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
 770         kunmap_atomic(kaddr);
 771         up_write(&EXT4_I(inode)->xattr_sem);
 772
 773         return iloc.bh;
 774 }
 775
 776 /*
 777  * Try to make the page cache and handle ready for the inline data case.
 778  * We can call this function in 2 cases:
 779  * 1. The inode is created and the first write exceeds inline size. We can
 780  *    clear the inode state safely.
 781  * 2. The inode has inline data, then we need to read the data, make it
 782  *    update and dirty so that ext4_da_writepages can handle it. We don't
 783  *    need to start the journal since the file's metatdata isn't changed now.
 784  */
 785 static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
 786                                                  struct inode *inode,
 787                                                  unsigned flags,
 788                                                  void **fsdata)
 789 {
 790         int ret = 0, inline_size;
 791         struct page *page;
 792
 793         page = grab_cache_page_write_begin(mapping, 0, flags);
 794         if (!page)
 795                 return -ENOMEM;
 796
 797         down_read(&EXT4_I(inode)->xattr_sem);
 798         if (!ext4_has_inline_data(inode)) {
 799                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 800                 goto out;
 801         }
 802
 803         inline_size = ext4_get_inline_size(inode);
 804
 805         if (!PageUptodate(page)) {
 806                 ret = ext4_read_inline_page(inode, page);
 807                 if (ret < 0)
 808                         goto out;
 809         }
 810
 811         ret = __block_write_begin(page, 0, inline_size,
 812                                   ext4_da_get_block_prep);
 813         if (ret) {
 814                 ext4_truncate_failed_write(inode);
 815                 goto out;
 816         }
 817
 818         SetPageDirty(page);
 819         SetPageUptodate(page);
 820         ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
 821         *fsdata = (void *)CONVERT_INLINE_DATA;
 822
 823 out:
 824         up_read(&EXT4_I(inode)->xattr_sem);
 825         if (page) {
 826                 unlock_page(page);
 827                 page_cache_release(page);
 828         }
 829         return ret;
 830 }
 831
 832 /*
 833  * Prepare the write for the inline data.
 834  * If the the data can be written into the inode, we just read
 835  * the page and make it uptodate, and start the journal.
 836  * Otherwise read the page, makes it dirty so that it can be
 837  * handle in writepages(the i_disksize update is left to the
 838  * normal ext4_da_write_end).
 839  */
 840 int ext4_da_write_inline_data_begin(struct address_space *mapping,
 841                                     struct inode *inode,
 842                                     loff_t pos, unsigned len,
 843                                     unsigned flags,
 844                                     struct page **pagep,
 845                                     void **fsdata)
 846 {
 847         int ret, inline_size;
 848         handle_t *handle;
 849         struct page *page;
 850         struct ext4_iloc iloc;
 851
 852         ret = ext4_get_inode_loc(inode, &iloc);
 853         if (ret)
 854                 return ret;
 855
 856         handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
 857         if (IS_ERR(handle)) {
 858                 ret = PTR_ERR(handle);
 859                 handle = NULL;
 860                 goto out;
 861         }
 862
 863         inline_size = ext4_get_max_inline_size(inode);
 864
 865         ret = -ENOSPC;
 866         if (inline_size >= pos + len) {
 867                 ret = ext4_prepare_inline_data(handle, inode, pos + len);
 868                 if (ret && ret != -ENOSPC)
 869                         goto out;
 870         }
 871
 872         if (ret == -ENOSPC) {
 873                 ret = ext4_da_convert_inline_data_to_extent(mapping,
 874                                                             inode,
 875                                                             flags,
 876                                                             fsdata);
 877                 goto out;
 878         }
 879
 880         /*
 881          * We cannot recurse into the filesystem as the transaction
 882          * is already started.
 883          */
 884         flags |= AOP_FLAG_NOFS;
 885
 886         page = grab_cache_page_write_begin(mapping, 0, flags);
 887         if (!page) {
 888                 ret = -ENOMEM;
 889                 goto out;
 890         }
 891
 892         down_read(&EXT4_I(inode)->xattr_sem);
 893         if (!ext4_has_inline_data(inode)) {
 894                 ret = 0;
 895                 goto out_release_page;
 896         }
 897
 898         if (!PageUptodate(page)) {
 899                 ret = ext4_read_inline_page(inode, page);
 900                 if (ret < 0)
 901                         goto out_release_page;
 902         }
 903
 904         up_read(&EXT4_I(inode)->xattr_sem);
 905         *pagep = page;
 906         handle = NULL;
 907         brelse(iloc.bh);
 908         return 1;
 909 out_release_page:
 910         up_read(&EXT4_I(inode)->xattr_sem);
 911         unlock_page(page);
 912         page_cache_release(page);
 913 out:
 914         if (handle)
 915                 ext4_journal_stop(handle);
 916         brelse(iloc.bh);
 917         return ret;
 918 }
 919
 920 int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
 921                                   unsigned len, unsigned copied,
 922                                   struct page *page)
 923 {
 924         int i_size_changed = 0;
 925
 926         copied = ext4_write_inline_data_end(inode, pos, len, copied, page);
 927
 928         /*
 929          * No need to use i_size_read() here, the i_size
 930          * cannot change under us because we hold i_mutex.
 931          *
 932          * But it's important to update i_size while still holding page lock:
 933          * page writeout could otherwise come in and zero beyond i_size.
 934          */
 935         if (pos+copied > inode->i_size) {
 936                 i_size_write(inode, pos+copied);
 937                 i_size_changed = 1;
 938         }
 939         unlock_page(page);
 940         page_cache_release(page);
 941
 942         /*
 943          * Don't mark the inode dirty under page lock. First, it unnecessarily
 944          * makes the holding time of page lock longer. Second, it forces lock
 945          * ordering of page lock and transaction start for journaling
 946          * filesystems.
 947          */
 948         if (i_size_changed)
 949                 mark_inode_dirty(inode);
 950
 951         return copied;
 952 }
 953
 954 #ifdef INLINE_DIR_DEBUG
 955 void ext4_show_inline_dir(struct inode *dir, struct buffer_head *bh,
 956                           void *inline_start, int inline_size)
 957 {
 958         int offset;
 959         unsigned short de_len;
 960         struct ext4_dir_entry_2 *de = inline_start;
 961         void *dlimit = inline_start + inline_size;
 962
 963         trace_printk("inode %lu\n", dir->i_ino);
 964         offset = 0;
 965         while ((void *)de < dlimit) {
 966                 de_len = ext4_rec_len_from_disk(de->rec_len, inline_size);
 967                 trace_printk("de: off %u rlen %u name %*.s nlen %u ino %u\n",
 968                              offset, de_len, de->name_len, de->name,
 969                              de->name_len, le32_to_cpu(de->inode));
 970                 if (ext4_check_dir_entry(dir, NULL, de, bh,
 971                                          inline_start, inline_size, offset))
 972                         BUG();
 973
 974                 offset += de_len;
 975                 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
 976         }
 977 }
 978 #else
 979 #define ext4_show_inline_dir(dir, bh, inline_start, inline_size)
 980 #endif
 981
 982 /*
 983  * Add a new entry into a inline dir.
 984  * It will return -ENOSPC if no space is available, and -EIO
 985  * and -EEXIST if directory entry already exists.
 986  */
 987 static int ext4_add_dirent_to_inline(handle_t *handle,
 988                                      struct dentry *dentry,
 989                                      struct inode *inode,
 990                                      struct ext4_iloc *iloc,
 991                                      void *inline_start, int inline_size)
 992 {
 993         struct inode    *dir = dentry->d_parent->d_inode;
 994         const char      *name = dentry->d_name.name;
 995         int             namelen = dentry->d_name.len;
 996         unsigned short  reclen;
 997         int             err;
 998         struct ext4_dir_entry_2 *de;
 999
1000         reclen = EXT4_DIR_REC_LEN(namelen);
1001         err = ext4_find_dest_de(dir, inode, iloc->bh,
1002                                 inline_start, inline_size,
1003                                 name, namelen, &de);
1004         if (err)
1005                 return err;
1006
1007         err = ext4_journal_get_write_access(handle, iloc->bh);
1008         if (err)
1009                 return err;
1010         ext4_insert_dentry(inode, de, inline_size, name, namelen);
1011
1012         ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
1013
1014         /*
1015          * XXX shouldn't update any times until successful
1016          * completion of syscall, but too many callers depend
1017          * on this.
1018          *
1019          * XXX similarly, too many callers depend on
1020          * ext4_new_inode() setting the times, but error
1021          * recovery deletes the inode, so the worst that can
1022          * happen is that the times are slightly out of date
1023          * and/or different from the directory change time.
1024          */
1025         dir->i_mtime = dir->i_ctime = ext4_current_time(dir);
1026         ext4_update_dx_flag(dir);
1027         dir->i_version++;
1028         ext4_mark_inode_dirty(handle, dir);
1029         return 1;
1030 }
1031
1032 static void *ext4_get_inline_xattr_pos(struct inode *inode,
1033                                        struct ext4_iloc *iloc)
1034 {
1035         struct ext4_xattr_entry *entry;
1036         struct ext4_xattr_ibody_header *header;
1037
1038         BUG_ON(!EXT4_I(inode)->i_inline_off);
1039
1040         header = IHDR(inode, ext4_raw_inode(iloc));
1041         entry = (struct ext4_xattr_entry *)((void *)ext4_raw_inode(iloc) +
1042                                             EXT4_I(inode)->i_inline_off);
1043
1044         return (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs);
1045 }
1046
1047 /* Set the final de to cover the whole block. */
1048 static void ext4_update_final_de(void *de_buf, int old_size, int new_size)
1049 {
1050         struct ext4_dir_entry_2 *de, *prev_de;
1051         void *limit;
1052         int de_len;
1053
1054         de = (struct ext4_dir_entry_2 *)de_buf;
1055         if (old_size) {
1056                 limit = de_buf + old_size;
1057                 do {
1058                         prev_de = de;
1059                         de_len = ext4_rec_len_from_disk(de->rec_len, old_size);
1060                         de_buf += de_len;
1061                         de = (struct ext4_dir_entry_2 *)de_buf;
1062                 } while (de_buf < limit);
1063
1064                 prev_de->rec_len = ext4_rec_len_to_disk(de_len + new_size -
1065                                                         old_size, new_size);
1066         } else {
1067                 /* this is just created, so create an empty entry. */
1068                 de->inode = 0;
1069                 de->rec_len = ext4_rec_len_to_disk(new_size, new_size);
1070         }
1071 }
1072
1073 static int ext4_update_inline_dir(handle_t *handle, struct inode *dir,
1074                                   struct ext4_iloc *iloc)
1075 {
1076         int ret;
1077         int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
1078         int new_size = get_max_inline_xattr_value_size(dir, iloc);
1079
1080         if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
1081                 return -ENOSPC;
1082
1083         ret = ext4_update_inline_data(handle, dir,
1084                                       new_size + EXT4_MIN_INLINE_DATA_SIZE);
1085         if (ret)
1086                 return ret;
1087
1088         ext4_update_final_de(ext4_get_inline_xattr_pos(dir, iloc), old_size,
1089                              EXT4_I(dir)->i_inline_size -
1090                                                 EXT4_MIN_INLINE_DATA_SIZE);
1091         dir->i_size = EXT4_I(dir)->i_disksize = EXT4_I(dir)->i_inline_size;
1092         return 0;
1093 }
1094
1095 static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
1096                                      struct ext4_iloc *iloc,
1097                                      void *buf, int inline_size)
1098 {
1099         ext4_create_inline_data(handle, inode, inline_size);
1100         ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
1101         ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1102 }
1103
1104 static int ext4_finish_convert_inline_dir(handle_t *handle,
1105                                           struct inode *inode,
1106                                           struct buffer_head *dir_block,
1107                                           void *buf,
1108                                           int inline_size)
1109 {
1110         int err, csum_size = 0, header_size = 0;
1111         struct ext4_dir_entry_2 *de;
1112         struct ext4_dir_entry_tail *t;
1113         void *target = dir_block->b_data;
1114
1115         /*
1116          * First create "." and ".." and then copy the dir information
1117          * back to the block.
1118          */
1119         de = (struct ext4_dir_entry_2 *)target;
1120         de = ext4_init_dot_dotdot(inode, de,
1121                 inode->i_sb->s_blocksize, csum_size,
1122                 le32_to_cpu(((struct ext4_dir_entry_2 *)buf)->inode), 1);
1123         header_size = (void *)de - target;
1124
1125         memcpy((void *)de, buf + EXT4_INLINE_DOTDOT_SIZE,
1126                 inline_size - EXT4_INLINE_DOTDOT_SIZE);
1127
1128         if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
1129                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1130                 csum_size = sizeof(struct ext4_dir_entry_tail);
1131
1132         inode->i_size = inode->i_sb->s_blocksize;
1133         i_size_write(inode, inode->i_sb->s_blocksize);
1134         EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
1135         ext4_update_final_de(dir_block->b_data,
1136                         inline_size - EXT4_INLINE_DOTDOT_SIZE + header_size,
1137                         inode->i_sb->s_blocksize - csum_size);
1138
1139         if (csum_size) {
1140                 t = EXT4_DIRENT_TAIL(dir_block->b_data,
1141                                      inode->i_sb->s_blocksize);
1142                 initialize_dirent_tail(t, inode->i_sb->s_blocksize);
1143         }
1144         set_buffer_uptodate(dir_block);
1145         err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
1146         if (err)
1147                 goto out;
1148         set_buffer_verified(dir_block);
1149 out:
1150         return err;
1151 }
1152
1153 static int ext4_convert_inline_data_nolock(handle_t *handle,
1154                                            struct inode *inode,
1155                                            struct ext4_iloc *iloc)
1156 {
1157         int error;
1158         void *buf = NULL;
1159         struct buffer_head *data_bh = NULL;
1160         struct ext4_map_blocks map;
1161         int inline_size;
1162
1163         inline_size = ext4_get_inline_size(inode);
1164         buf = kmalloc(inline_size, GFP_NOFS);
1165         if (!buf) {
1166                 error = -ENOMEM;
1167                 goto out;
1168         }
1169
1170         error = ext4_read_inline_data(inode, buf, inline_size, iloc);
1171         if (error < 0)
1172                 goto out;
1173
1174         error = ext4_destroy_inline_data_nolock(handle, inode);
1175         if (error)
1176                 goto out;
1177
1178         map.m_lblk = 0;
1179         map.m_len = 1;
1180         map.m_flags = 0;
1181         error = ext4_map_blocks(handle, inode, &map, EXT4_GET_BLOCKS_CREATE);
1182         if (error < 0)
1183                 goto out_restore;
1184         if (!(map.m_flags & EXT4_MAP_MAPPED)) {
1185                 error = -EIO;
1186                 goto out_restore;
1187         }
1188
1189         data_bh = sb_getblk(inode->i_sb, map.m_pblk);
1190         if (!data_bh) {
1191                 error = -ENOMEM;
1192                 goto out_restore;
1193         }
1194
1195         lock_buffer(data_bh);
1196         error = ext4_journal_get_create_access(handle, data_bh);
1197         if (error) {
1198                 unlock_buffer(data_bh);
1199                 error = -EIO;
1200                 goto out_restore;
1201         }
1202         memset(data_bh->b_data, 0, inode->i_sb->s_blocksize);
1203
1204         if (!S_ISDIR(inode->i_mode)) {
1205                 memcpy(data_bh->b_data, buf, inline_size);
1206                 set_buffer_uptodate(data_bh);
1207                 error = ext4_handle_dirty_metadata(handle,
1208                                                    inode, data_bh);
1209         } else {
1210                 error = ext4_finish_convert_inline_dir(handle, inode, data_bh,
1211                                                        buf, inline_size);
1212         }
1213
1214         unlock_buffer(data_bh);
1215 out_restore:
1216         if (error)
1217                 ext4_restore_inline_data(handle, inode, iloc, buf, inline_size);
1218
1219 out:
1220         brelse(data_bh);
1221         kfree(buf);
1222         return error;
1223 }
1224
1225 /*
1226  * Try to add the new entry to the inline data.
1227  * If succeeds, return 0. If not, extended the inline dir and copied data to
1228  * the new created block.
1229  */
1230 int ext4_try_add_inline_entry(handle_t *handle, struct dentry *dentry,
1231                               struct inode *inode)
1232 {
1233         int ret, inline_size;
1234         void *inline_start;
1235         struct ext4_iloc iloc;
1236         struct inode *dir = dentry->d_parent->d_inode;
1237
1238         ret = ext4_get_inode_loc(dir, &iloc);
1239         if (ret)
1240                 return ret;
1241
1242         down_write(&EXT4_I(dir)->xattr_sem);
1243         if (!ext4_has_inline_data(dir))
1244                 goto out;
1245
1246         inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1247                                                  EXT4_INLINE_DOTDOT_SIZE;
1248         inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1249
1250         ret = ext4_add_dirent_to_inline(handle, dentry, inode, &iloc,
1251                                         inline_start, inline_size);
1252         if (ret != -ENOSPC)
1253                 goto out;
1254
1255         /* check whether it can be inserted to inline xattr space. */
1256         inline_size = EXT4_I(dir)->i_inline_size -
1257                         EXT4_MIN_INLINE_DATA_SIZE;
1258         if (!inline_size) {
1259                 /* Try to use the xattr space.*/
1260                 ret = ext4_update_inline_dir(handle, dir, &iloc);
1261                 if (ret && ret != -ENOSPC)
1262                         goto out;
1263
1264                 inline_size = EXT4_I(dir)->i_inline_size -
1265                                 EXT4_MIN_INLINE_DATA_SIZE;
1266         }
1267
1268         if (inline_size) {
1269                 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1270
1271                 ret = ext4_add_dirent_to_inline(handle, dentry, inode, &iloc,
1272                                                 inline_start, inline_size);
1273
1274                 if (ret != -ENOSPC)
1275                         goto out;
1276         }
1277
1278         /*
1279          * The inline space is filled up, so create a new block for it.
1280          * As the extent tree will be created, we have to save the inline
1281          * dir first.
1282          */
1283         ret = ext4_convert_inline_data_nolock(handle, dir, &iloc);
1284
1285 out:
1286         ext4_mark_inode_dirty(handle, dir);
1287         up_write(&EXT4_I(dir)->xattr_sem);
1288         brelse(iloc.bh);
1289         return ret;
1290 }
1291
1292 int ext4_read_inline_dir(struct file *filp,
1293                          void *dirent, filldir_t filldir,
1294                          int *has_inline_data)
1295 {
1296         int error = 0;
1297         unsigned int offset, parent_ino;
1298         int i, stored;
1299         struct ext4_dir_entry_2 *de;
1300         struct super_block *sb;
1301         struct inode *inode = file_inode(filp);
1302         int ret, inline_size = 0;
1303         struct ext4_iloc iloc;
1304         void *dir_buf = NULL;
1305
1306         ret = ext4_get_inode_loc(inode, &iloc);
1307         if (ret)
1308                 return ret;
1309
1310         down_read(&EXT4_I(inode)->xattr_sem);
1311         if (!ext4_has_inline_data(inode)) {
1312                 up_read(&EXT4_I(inode)->xattr_sem);
1313                 *has_inline_data = 0;
1314                 goto out;
1315         }
1316
1317         inline_size = ext4_get_inline_size(inode);
1318         dir_buf = kmalloc(inline_size, GFP_NOFS);
1319         if (!dir_buf) {
1320                 ret = -ENOMEM;
1321                 up_read(&EXT4_I(inode)->xattr_sem);
1322                 goto out;
1323         }
1324
1325         ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
1326         up_read(&EXT4_I(inode)->xattr_sem);
1327         if (ret < 0)
1328                 goto out;
1329
1330         sb = inode->i_sb;
1331         stored = 0;
1332         parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
1333
1334         while (!error && !stored && filp->f_pos < inode->i_size) {
1335 revalidate:
1336                 /*
1337                  * If the version has changed since the last call to
1338                  * readdir(2), then we might be pointing to an invalid
1339                  * dirent right now.  Scan from the start of the inline
1340                  * dir to make sure.
1341                  */
1342                 if (filp->f_version != inode->i_version) {
1343                         for (i = 0;
1344                              i < inode->i_size && i < offset;) {
1345                                 if (!i) {
1346                                         /* skip "." and ".." if needed. */
1347                                         i += EXT4_INLINE_DOTDOT_SIZE;
1348                                         continue;
1349                                 }
1350                                 de = (struct ext4_dir_entry_2 *)
1351                                         (dir_buf + i);
1352                                 /* It's too expensive to do a full
1353                                  * dirent test each time round this
1354                                  * loop, but we do have to test at
1355                                  * least that it is non-zero.  A
1356                                  * failure will be detected in the
1357                                  * dirent test below. */
1358                                 if (ext4_rec_len_from_disk(de->rec_len,
1359                                         inline_size) < EXT4_DIR_REC_LEN(1))
1360                                         break;
1361                                 i += ext4_rec_len_from_disk(de->rec_len,
1362                                                             inline_size);
1363                         }
1364                         offset = i;
1365                         filp->f_pos = offset;
1366                         filp->f_version = inode->i_version;
1367                 }
1368
1369                 while (!error && filp->f_pos < inode->i_size) {
1370                         if (filp->f_pos == 0) {
1371                                 error = filldir(dirent, ".", 1, 0, inode->i_ino,
1372                                                 DT_DIR);
1373                                 if (error)
1374                                         break;
1375                                 stored++;
1376
1377                                 error = filldir(dirent, "..", 2, 0, parent_ino,
1378                                                 DT_DIR);
1379                                 if (error)
1380                                         break;
1381                                 stored++;
1382
1383                                 filp->f_pos = offset = EXT4_INLINE_DOTDOT_SIZE;
1384                                 continue;
1385                         }
1386
1387                         de = (struct ext4_dir_entry_2 *)(dir_buf + offset);
1388                         if (ext4_check_dir_entry(inode, filp, de,
1389                                                  iloc.bh, dir_buf,
1390                                                  inline_size, offset)) {
1391                                 ret = stored;
1392                                 goto out;
1393                         }
1394                         offset += ext4_rec_len_from_disk(de->rec_len,
1395                                                          inline_size);
1396                         if (le32_to_cpu(de->inode)) {
1397                                 /* We might block in the next section
1398                                  * if the data destination is
1399                                  * currently swapped out.  So, use a
1400                                  * version stamp to detect whether or
1401                                  * not the directory has been modified
1402                                  * during the copy operation.
1403                                  */
1404                                 u64 version = filp->f_version;
1405
1406                                 error = filldir(dirent, de->name,
1407                                                 de->name_len,
1408                                                 filp->f_pos,
1409                                                 le32_to_cpu(de->inode),
1410                                                 get_dtype(sb, de->file_type));
1411                                 if (error)
1412                                         break;
1413                                 if (version != filp->f_version)
1414                                         goto revalidate;
1415                                 stored++;
1416                         }
1417                         filp->f_pos += ext4_rec_len_from_disk(de->rec_len,
1418                                                               inline_size);
1419                 }
1420                 offset = 0;
1421         }
1422 out:
1423         kfree(dir_buf);
1424         brelse(iloc.bh);
1425         return ret;
1426 }
1427
1428 struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
1429                                         struct ext4_dir_entry_2 **parent_de,
1430                                         int *retval)
1431 {
1432         struct ext4_iloc iloc;
1433
1434         *retval = ext4_get_inode_loc(inode, &iloc);
1435         if (*retval)
1436                 return NULL;
1437
1438         *parent_de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1439
1440         return iloc.bh;
1441 }
1442
1443 /*
1444  * Try to create the inline data for the new dir.
1445  * If it succeeds, return 0, otherwise return the error.
1446  * In case of ENOSPC, the caller should create the normal disk layout dir.
1447  */
1448 int ext4_try_create_inline_dir(handle_t *handle, struct inode *parent,
1449                                struct inode *inode)
1450 {
1451         int ret, inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1452         struct ext4_iloc iloc;
1453         struct ext4_dir_entry_2 *de;
1454
1455         ret = ext4_get_inode_loc(inode, &iloc);
1456         if (ret)
1457                 return ret;
1458
1459         ret = ext4_prepare_inline_data(handle, inode, inline_size);
1460         if (ret)
1461                 goto out;
1462
1463         /*
1464          * For inline dir, we only save the inode information for the ".."
1465          * and create a fake dentry to cover the left space.
1466          */
1467         de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1468         de->inode = cpu_to_le32(parent->i_ino);
1469         de = (struct ext4_dir_entry_2 *)((void *)de + EXT4_INLINE_DOTDOT_SIZE);
1470         de->inode = 0;
1471         de->rec_len = ext4_rec_len_to_disk(
1472                                 inline_size - EXT4_INLINE_DOTDOT_SIZE,
1473                                 inline_size);
1474         set_nlink(inode, 2);
1475         inode->i_size = EXT4_I(inode)->i_disksize = inline_size;
1476 out:
1477         brelse(iloc.bh);
1478         return ret;
1479 }
1480
1481 struct buffer_head *ext4_find_inline_entry(struct inode *dir,
1482                                         const struct qstr *d_name,
1483                                         struct ext4_dir_entry_2 **res_dir,
1484                                         int *has_inline_data)
1485 {
1486         int ret;
1487         struct ext4_iloc iloc;
1488         void *inline_start;
1489         int inline_size;
1490
1491         if (ext4_get_inode_loc(dir, &iloc))
1492                 return NULL;
1493
1494         down_read(&EXT4_I(dir)->xattr_sem);
1495         if (!ext4_has_inline_data(dir)) {
1496                 *has_inline_data = 0;
1497                 goto out;
1498         }
1499
1500         inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1501                                                 EXT4_INLINE_DOTDOT_SIZE;
1502         inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
1503         ret = search_dir(iloc.bh, inline_start, inline_size,
1504                          dir, d_name, 0, res_dir);
1505         if (ret == 1)
1506                 goto out_find;
1507         if (ret < 0)
1508                 goto out;
1509
1510         if (ext4_get_inline_size(dir) == EXT4_MIN_INLINE_DATA_SIZE)
1511                 goto out;
1512
1513         inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1514         inline_size = ext4_get_inline_size(dir) - EXT4_MIN_INLINE_DATA_SIZE;
1515
1516         ret = search_dir(iloc.bh, inline_start, inline_size,
1517                          dir, d_name, 0, res_dir);
1518         if (ret == 1)
1519                 goto out_find;
1520
1521 out:
1522         brelse(iloc.bh);
1523         iloc.bh = NULL;
1524 out_find:
1525         up_read(&EXT4_I(dir)->xattr_sem);
1526         return iloc.bh;
1527 }
1528
1529 int ext4_delete_inline_entry(handle_t *handle,
1530                              struct inode *dir,
1531                              struct ext4_dir_entry_2 *de_del,
1532                              struct buffer_head *bh,
1533                              int *has_inline_data)
1534 {
1535         int err, inline_size;
1536         struct ext4_iloc iloc;
1537         void *inline_start;
1538
1539         err = ext4_get_inode_loc(dir, &iloc);
1540         if (err)
1541                 return err;
1542
1543         down_write(&EXT4_I(dir)->xattr_sem);
1544         if (!ext4_has_inline_data(dir)) {
1545                 *has_inline_data = 0;
1546                 goto out;
1547         }
1548
1549         if ((void *)de_del - ((void *)ext4_raw_inode(&iloc)->i_block) <
1550                 EXT4_MIN_INLINE_DATA_SIZE) {
1551                 inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
1552                                         EXT4_INLINE_DOTDOT_SIZE;
1553                 inline_size = EXT4_MIN_INLINE_DATA_SIZE -
1554                                 EXT4_INLINE_DOTDOT_SIZE;
1555         } else {
1556                 inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
1557                 inline_size = ext4_get_inline_size(dir) -
1558                                 EXT4_MIN_INLINE_DATA_SIZE;
1559         }
1560
1561         err = ext4_journal_get_write_access(handle, bh);
1562         if (err)
1563                 goto out;
1564
1565         err = ext4_generic_delete_entry(handle, dir, de_del, bh,
1566                                         inline_start, inline_size, 0);
1567         if (err)
1568                 goto out;
1569
1570         BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
1571         err = ext4_mark_inode_dirty(handle, dir);
1572         if (unlikely(err))
1573                 goto out;
1574
1575         ext4_show_inline_dir(dir, iloc.bh, inline_start, inline_size);
1576 out:
1577         up_write(&EXT4_I(dir)->xattr_sem);
1578         brelse(iloc.bh);
1579         if (err != -ENOENT)
1580                 ext4_std_error(dir->i_sb, err);
1581         return err;
1582 }
1583
1584 /*
1585  * Get the inline dentry at offset.
1586  */
1587 static inline struct ext4_dir_entry_2 *
1588 ext4_get_inline_entry(struct inode *inode,
1589                       struct ext4_iloc *iloc,
1590                       unsigned int offset,
1591                       void **inline_start,
1592                       int *inline_size)
1593 {
1594         void *inline_pos;
1595
1596         BUG_ON(offset > ext4_get_inline_size(inode));
1597
1598         if (offset < EXT4_MIN_INLINE_DATA_SIZE) {
1599                 inline_pos = (void *)ext4_raw_inode(iloc)->i_block;
1600                 *inline_size = EXT4_MIN_INLINE_DATA_SIZE;
1601         } else {
1602                 inline_pos = ext4_get_inline_xattr_pos(inode, iloc);
1603                 offset -= EXT4_MIN_INLINE_DATA_SIZE;
1604                 *inline_size = ext4_get_inline_size(inode) -
1605                                 EXT4_MIN_INLINE_DATA_SIZE;
1606         }
1607
1608         if (inline_start)
1609                 *inline_start = inline_pos;
1610         return (struct ext4_dir_entry_2 *)(inline_pos + offset);
1611 }
1612
1613 int empty_inline_dir(struct inode *dir, int *has_inline_data)
1614 {
1615         int err, inline_size;
1616         struct ext4_iloc iloc;
1617         void *inline_pos;
1618         unsigned int offset;
1619         struct ext4_dir_entry_2 *de;
1620         int ret = 1;
1621
1622         err = ext4_get_inode_loc(dir, &iloc);
1623         if (err) {
1624                 EXT4_ERROR_INODE(dir, "error %d getting inode %lu block",
1625                                  err, dir->i_ino);
1626                 return 1;
1627         }
1628
1629         down_read(&EXT4_I(dir)->xattr_sem);
1630         if (!ext4_has_inline_data(dir)) {
1631                 *has_inline_data = 0;
1632                 goto out;
1633         }
1634
1635         de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
1636         if (!le32_to_cpu(de->inode)) {
1637                 ext4_warning(dir->i_sb,
1638                              "bad inline directory (dir #%lu) - no `..'",
1639                              dir->i_ino);
1640                 ret = 1;
1641                 goto out;
1642         }
1643
1644         offset = EXT4_INLINE_DOTDOT_SIZE;
1645         while (offset < dir->i_size) {
1646                 de = ext4_get_inline_entry(dir, &iloc, offset,
1647                                            &inline_pos, &inline_size);
1648                 if (ext4_check_dir_entry(dir, NULL, de,
1649                                          iloc.bh, inline_pos,
1650                                          inline_size, offset)) {
1651                         ext4_warning(dir->i_sb,
1652                                      "bad inline directory (dir #%lu) - "
1653                                      "inode %u, rec_len %u, name_len %d"
1654                                      "inline size %d\n",
1655                                      dir->i_ino, le32_to_cpu(de->inode),
1656                                      le16_to_cpu(de->rec_len), de->name_len,
1657                                      inline_size);
1658                         ret = 1;
1659                         goto out;
1660                 }
1661                 if (le32_to_cpu(de->inode)) {
1662                         ret = 0;
1663                         goto out;
1664                 }
1665                 offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
1666         }
1667
1668 out:
1669         up_read(&EXT4_I(dir)->xattr_sem);
1670         brelse(iloc.bh);
1671         return ret;
1672 }
1673
1674 int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
1675 {
1676         int ret;
1677
1678         down_write(&EXT4_I(inode)->xattr_sem);
1679         ret = ext4_destroy_inline_data_nolock(handle, inode);
1680         up_write(&EXT4_I(inode)->xattr_sem);
1681
1682         return ret;
1683 }
1684
1685 int ext4_inline_data_fiemap(struct inode *inode,
1686                             struct fiemap_extent_info *fieinfo,
1687                             int *has_inline)
1688 {
1689         __u64 physical = 0;
1690         __u64 length;
1691         __u32 flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_LAST;
1692         int error = 0;
1693         struct ext4_iloc iloc;
1694
1695         down_read(&EXT4_I(inode)->xattr_sem);
1696         if (!ext4_has_inline_data(inode)) {
1697                 *has_inline = 0;
1698                 goto out;
1699         }
1700
1701         error = ext4_get_inode_loc(inode, &iloc);
1702         if (error)
1703                 goto out;
1704
1705         physical = iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
1706         physical += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
1707         physical += offsetof(struct ext4_inode, i_block);
1708         length = i_size_read(inode);
1709
1710         if (physical)
1711                 error = fiemap_fill_next_extent(fieinfo, 0, physical,
1712                                                 length, flags);
1713         brelse(iloc.bh);
1714 out:
1715         up_read(&EXT4_I(inode)->xattr_sem);
1716         return (error < 0 ? error : 0);
1717 }
1718
1719 /*
1720  * Called during xattr set, and if we can sparse space 'needed',
1721  * just create the extent tree evict the data to the outer block.
1722  *
1723  * We use jbd2 instead of page cache to move data to the 1st block
1724  * so that the whole transaction can be committed as a whole and
1725  * the data isn't lost because of the delayed page cache write.
1726  */
1727 int ext4_try_to_evict_inline_data(handle_t *handle,
1728                                   struct inode *inode,
1729                                   int needed)
1730 {
1731         int error;
1732         struct ext4_xattr_entry *entry;
1733         struct ext4_xattr_ibody_header *header;
1734         struct ext4_inode *raw_inode;
1735         struct ext4_iloc iloc;
1736
1737         error = ext4_get_inode_loc(inode, &iloc);
1738         if (error)
1739                 return error;
1740
1741         raw_inode = ext4_raw_inode(&iloc);
1742         header = IHDR(inode, raw_inode);
1743         entry = (struct ext4_xattr_entry *)((void *)raw_inode +
1744                                             EXT4_I(inode)->i_inline_off);
1745         if (EXT4_XATTR_LEN(entry->e_name_len) +
1746             EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)) < needed) {
1747                 error = -ENOSPC;
1748                 goto out;
1749         }
1750
1751         error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
1752 out:
1753         brelse(iloc.bh);
1754         return error;
1755 }
1756
1757 void ext4_inline_data_truncate(struct inode *inode, int *has_inline)
1758 {
1759         handle_t *handle;
1760         int inline_size, value_len, needed_blocks;
1761         size_t i_size;
1762         void *value = NULL;
1763         struct ext4_xattr_ibody_find is = {
1764                 .s = { .not_found = -ENODATA, },
1765         };
1766         struct ext4_xattr_info i = {
1767                 .name_index = EXT4_XATTR_INDEX_SYSTEM,
1768                 .name = EXT4_XATTR_SYSTEM_DATA,
1769         };
1770
1771
1772         needed_blocks = ext4_writepage_trans_blocks(inode);
1773         handle = ext4_journal_start(inode, EXT4_HT_INODE, needed_blocks);
1774         if (IS_ERR(handle))
1775                 return;
1776
1777         down_write(&EXT4_I(inode)->xattr_sem);
1778         if (!ext4_has_inline_data(inode)) {
1779                 *has_inline = 0;
1780                 ext4_journal_stop(handle);
1781                 return;
1782         }
1783
1784         if (ext4_orphan_add(handle, inode))
1785                 goto out;
1786
1787         if (ext4_get_inode_loc(inode, &is.iloc))
1788                 goto out;
1789
1790         down_write(&EXT4_I(inode)->i_data_sem);
1791         i_size = inode->i_size;
1792         inline_size = ext4_get_inline_size(inode);
1793         EXT4_I(inode)->i_disksize = i_size;
1794
1795         if (i_size < inline_size) {
1796                 /* Clear the content in the xattr space. */
1797                 if (inline_size > EXT4_MIN_INLINE_DATA_SIZE) {
1798                         if (ext4_xattr_ibody_find(inode, &i, &is))
1799                                 goto out_error;
1800
1801                         BUG_ON(is.s.not_found);
1802
1803                         value_len = le32_to_cpu(is.s.here->e_value_size);
1804                         value = kmalloc(value_len, GFP_NOFS);
1805                         if (!value)
1806                                 goto out_error;
1807
1808                         if (ext4_xattr_ibody_get(inode, i.name_index, i.name,
1809                                                 value, value_len))
1810                                 goto out_error;
1811
1812                         i.value = value;
1813                         i.value_len = i_size > EXT4_MIN_INLINE_DATA_SIZE ?
1814                                         i_size - EXT4_MIN_INLINE_DATA_SIZE : 0;
1815                         if (ext4_xattr_ibody_inline_set(handle, inode, &i, &is))
1816                                 goto out_error;
1817                 }
1818
1819                 /* Clear the content within i_blocks. */
1820                 if (i_size < EXT4_MIN_INLINE_DATA_SIZE)
1821                         memset(ext4_raw_inode(&is.iloc)->i_block + i_size, 0,
1822                                         EXT4_MIN_INLINE_DATA_SIZE - i_size);
1823
1824                 EXT4_I(inode)->i_inline_size = i_size <
1825                                         EXT4_MIN_INLINE_DATA_SIZE ?
1826                                         EXT4_MIN_INLINE_DATA_SIZE : i_size;
1827         }
1828
1829 out_error:
1830         up_write(&EXT4_I(inode)->i_data_sem);
1831 out:
1832         brelse(is.iloc.bh);
1833         up_write(&EXT4_I(inode)->xattr_sem);
1834         kfree(value);
1835         if (inode->i_nlink)
1836                 ext4_orphan_del(handle, inode);
1837
1838         inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
1839         ext4_mark_inode_dirty(handle, inode);
1840         if (IS_SYNC(inode))
1841                 ext4_handle_sync(handle);
1842
1843         ext4_journal_stop(handle);
1844         return;
1845 }
1846
1847 int ext4_convert_inline_data(struct inode *inode)
1848 {
1849         int error, needed_blocks;
1850         handle_t *handle;
1851         struct ext4_iloc iloc;
1852
1853         if (!ext4_has_inline_data(inode)) {
1854                 ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
1855                 return 0;
1856         }
1857
1858         needed_blocks = ext4_writepage_trans_blocks(inode);
1859
1860         iloc.bh = NULL;
1861         error = ext4_get_inode_loc(inode, &iloc);
1862         if (error)
1863                 return error;
1864
1865         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
1866         if (IS_ERR(handle)) {
1867                 error = PTR_ERR(handle);
1868                 goto out_free;
1869         }
1870
1871         down_write(&EXT4_I(inode)->xattr_sem);
1872         if (!ext4_has_inline_data(inode)) {
1873                 up_write(&EXT4_I(inode)->xattr_sem);
1874                 goto out;
1875         }
1876
1877         error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
1878         up_write(&EXT4_I(inode)->xattr_sem);
1879 out:
1880         ext4_journal_stop(handle);
1881 out_free:
1882         brelse(iloc.bh);
1883         return error;
1884 }