fs/f2fs/namei.c

   1 /*
   2  * fs/f2fs/namei.c
   3  *
   4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5  *             http://www.samsung.com/
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/fs.h>
  12 #include <linux/f2fs_fs.h>
  13 #include <linux/pagemap.h>
  14 #include <linux/sched.h>
  15 #include <linux/ctype.h>
  16 #include <linux/dcache.h>
  17 #include <linux/namei.h>
  18
  19 #include "f2fs.h"
  20 #include "node.h"
  21 #include "xattr.h"
  22 #include "acl.h"
  23 #include <trace/events/f2fs.h>
  24
  25 static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
  26 {
  27         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
  28         nid_t ino;
  29         struct inode *inode;
  30         bool nid_free = false;
  31         int err;
  32
  33         inode = new_inode(dir->i_sb);
  34         if (!inode)
  35                 return ERR_PTR(-ENOMEM);
  36
  37         f2fs_lock_op(sbi);
  38         if (!alloc_nid(sbi, &ino)) {
  39                 f2fs_unlock_op(sbi);
  40                 err = -ENOSPC;
  41                 goto fail;
  42         }
  43         f2fs_unlock_op(sbi);
  44
  45         inode_init_owner(inode, dir, mode);
  46
  47         inode->i_ino = ino;
  48         inode->i_blocks = 0;
  49         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
  50         inode->i_generation = sbi->s_next_generation++;
  51
  52         err = insert_inode_locked(inode);
  53         if (err) {
  54                 err = -EINVAL;
  55                 nid_free = true;
  56                 goto out;
  57         }
  58
  59         /* If the directory encrypted, then we should encrypt the inode. */
  60         if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode))
  61                 f2fs_set_encrypted_inode(inode);
  62
  63         if (f2fs_may_inline_data(inode))
  64                 set_inode_flag(F2FS_I(inode), FI_INLINE_DATA);
  65         if (f2fs_may_inline_dentry(inode))
  66                 set_inode_flag(F2FS_I(inode), FI_INLINE_DENTRY);
  67
  68         stat_inc_inline_inode(inode);
  69         stat_inc_inline_dir(inode);
  70
  71         trace_f2fs_new_inode(inode, 0);
  72         mark_inode_dirty(inode);
  73         return inode;
  74
  75 out:
  76         clear_nlink(inode);
  77         unlock_new_inode(inode);
  78 fail:
  79         trace_f2fs_new_inode(inode, err);
  80         make_bad_inode(inode);
  81         iput(inode);
  82         if (nid_free)
  83                 alloc_nid_failed(sbi, ino);
  84         return ERR_PTR(err);
  85 }
  86
  87 static int is_multimedia_file(const unsigned char *s, const char *sub)
  88 {
  89         size_t slen = strlen(s);
  90         size_t sublen = strlen(sub);
  91
  92         if (sublen > slen)
  93                 return 0;
  94
  95         return !strncasecmp(s + slen - sublen, sub, sublen);
  96 }
  97
  98 /*
  99  * Set multimedia files as cold files for hot/cold data separation
 100  */
 101 static inline void set_cold_files(struct f2fs_sb_info *sbi, struct inode *inode,
 102                 const unsigned char *name)
 103 {
 104         int i;
 105         __u8 (*extlist)[8] = sbi->raw_super->extension_list;
 106
 107         int count = le32_to_cpu(sbi->raw_super->extension_count);
 108         for (i = 0; i < count; i++) {
 109                 if (is_multimedia_file(name, extlist[i])) {
 110                         file_set_cold(inode);
 111                         break;
 112                 }
 113         }
 114 }
 115
 116 static int f2fs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 117                                                 bool excl)
 118 {
 119         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 120         struct inode *inode;
 121         nid_t ino = 0;
 122         int err;
 123
 124         f2fs_balance_fs(sbi);
 125
 126         inode = f2fs_new_inode(dir, mode);
 127         if (IS_ERR(inode))
 128                 return PTR_ERR(inode);
 129
 130         if (!test_opt(sbi, DISABLE_EXT_IDENTIFY))
 131                 set_cold_files(sbi, inode, dentry->d_name.name);
 132
 133         inode->i_op = &f2fs_file_inode_operations;
 134         inode->i_fop = &f2fs_file_operations;
 135         inode->i_mapping->a_ops = &f2fs_dblock_aops;
 136         ino = inode->i_ino;
 137
 138         f2fs_lock_op(sbi);
 139         err = f2fs_add_link(dentry, inode);
 140         if (err)
 141                 goto out;
 142         f2fs_unlock_op(sbi);
 143
 144         alloc_nid_done(sbi, ino);
 145
 146         d_instantiate(dentry, inode);
 147         unlock_new_inode(inode);
 148
 149         if (IS_DIRSYNC(dir))
 150                 f2fs_sync_fs(sbi->sb, 1);
 151         return 0;
 152 out:
 153         handle_failed_inode(inode);
 154         return err;
 155 }
 156
 157 static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
 158                 struct dentry *dentry)
 159 {
 160         struct inode *inode = d_inode(old_dentry);
 161         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 162         int err;
 163
 164         if (f2fs_encrypted_inode(dir) &&
 165                 !f2fs_is_child_context_consistent_with_parent(dir, inode))
 166                 return -EPERM;
 167
 168         f2fs_balance_fs(sbi);
 169
 170         inode->i_ctime = CURRENT_TIME;
 171         ihold(inode);
 172
 173         set_inode_flag(F2FS_I(inode), FI_INC_LINK);
 174         f2fs_lock_op(sbi);
 175         err = f2fs_add_link(dentry, inode);
 176         if (err)
 177                 goto out;
 178         f2fs_unlock_op(sbi);
 179
 180         d_instantiate(dentry, inode);
 181
 182         if (IS_DIRSYNC(dir))
 183                 f2fs_sync_fs(sbi->sb, 1);
 184         return 0;
 185 out:
 186         clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
 187         iput(inode);
 188         f2fs_unlock_op(sbi);
 189         return err;
 190 }
 191
 192 struct dentry *f2fs_get_parent(struct dentry *child)
 193 {
 194         struct qstr dotdot = QSTR_INIT("..", 2);
 195         unsigned long ino = f2fs_inode_by_name(d_inode(child), &dotdot);
 196         if (!ino)
 197                 return ERR_PTR(-ENOENT);
 198         return d_obtain_alias(f2fs_iget(d_inode(child)->i_sb, ino));
 199 }
 200
 201 static int __recover_dot_dentries(struct inode *dir, nid_t pino)
 202 {
 203         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 204         struct qstr dot = QSTR_INIT(".", 1);
 205         struct qstr dotdot = QSTR_INIT("..", 2);
 206         struct f2fs_dir_entry *de;
 207         struct page *page;
 208         int err = 0;
 209
 210         f2fs_lock_op(sbi);
 211
 212         de = f2fs_find_entry(dir, &dot, &page);
 213         if (de) {
 214                 f2fs_dentry_kunmap(dir, page);
 215                 f2fs_put_page(page, 0);
 216         } else {
 217                 err = __f2fs_add_link(dir, &dot, NULL, dir->i_ino, S_IFDIR);
 218                 if (err)
 219                         goto out;
 220         }
 221
 222         de = f2fs_find_entry(dir, &dotdot, &page);
 223         if (de) {
 224                 f2fs_dentry_kunmap(dir, page);
 225                 f2fs_put_page(page, 0);
 226         } else {
 227                 err = __f2fs_add_link(dir, &dotdot, NULL, pino, S_IFDIR);
 228         }
 229 out:
 230         if (!err) {
 231                 clear_inode_flag(F2FS_I(dir), FI_INLINE_DOTS);
 232                 mark_inode_dirty(dir);
 233         }
 234
 235         f2fs_unlock_op(sbi);
 236         return err;
 237 }
 238
 239 static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
 240                 unsigned int flags)
 241 {
 242         struct inode *inode = NULL;
 243         struct f2fs_dir_entry *de;
 244         struct page *page;
 245         nid_t ino;
 246         int err = 0;
 247
 248         if (dentry->d_name.len > F2FS_NAME_LEN)
 249                 return ERR_PTR(-ENAMETOOLONG);
 250
 251         de = f2fs_find_entry(dir, &dentry->d_name, &page);
 252         if (!de)
 253                 return d_splice_alias(inode, dentry);
 254
 255         ino = le32_to_cpu(de->ino);
 256         f2fs_dentry_kunmap(dir, page);
 257         f2fs_put_page(page, 0);
 258
 259         inode = f2fs_iget(dir->i_sb, ino);
 260         if (IS_ERR(inode))
 261                 return ERR_CAST(inode);
 262
 263         if (f2fs_has_inline_dots(inode)) {
 264                 err = __recover_dot_dentries(inode, dir->i_ino);
 265                 if (err)
 266                         goto err_out;
 267         }
 268         return d_splice_alias(inode, dentry);
 269
 270 err_out:
 271         iget_failed(inode);
 272         return ERR_PTR(err);
 273 }
 274
 275 static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
 276 {
 277         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 278         struct inode *inode = d_inode(dentry);
 279         struct f2fs_dir_entry *de;
 280         struct page *page;
 281         int err = -ENOENT;
 282
 283         trace_f2fs_unlink_enter(dir, dentry);
 284         f2fs_balance_fs(sbi);
 285
 286         de = f2fs_find_entry(dir, &dentry->d_name, &page);
 287         if (!de)
 288                 goto fail;
 289
 290         f2fs_lock_op(sbi);
 291         err = acquire_orphan_inode(sbi);
 292         if (err) {
 293                 f2fs_unlock_op(sbi);
 294                 f2fs_dentry_kunmap(dir, page);
 295                 f2fs_put_page(page, 0);
 296                 goto fail;
 297         }
 298         f2fs_delete_entry(de, page, dir, inode);
 299         f2fs_unlock_op(sbi);
 300
 301         /* In order to evict this inode, we set it dirty */
 302         mark_inode_dirty(inode);
 303
 304         if (IS_DIRSYNC(dir))
 305                 f2fs_sync_fs(sbi->sb, 1);
 306 fail:
 307         trace_f2fs_unlink_exit(inode, err);
 308         return err;
 309 }
 310
 311 static const char *f2fs_follow_link(struct dentry *dentry, void **cookie)
 312 {
 313         const char *link = page_follow_link_light(dentry, cookie);
 314         if (!IS_ERR(link) && !*link) {
 315                 /* this is broken symlink case */
 316                 page_put_link(NULL, *cookie);
 317                 link = ERR_PTR(-ENOENT);
 318         }
 319         return link;
 320 }
 321
 322 static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
 323                                         const char *symname)
 324 {
 325         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 326         struct inode *inode;
 327         size_t len = strlen(symname);
 328         size_t p_len;
 329         char *p_str;
 330         struct f2fs_str disk_link = FSTR_INIT(NULL, 0);
 331         struct f2fs_encrypted_symlink_data *sd = NULL;
 332         int err;
 333
 334         if (len > dir->i_sb->s_blocksize)
 335                 return -ENAMETOOLONG;
 336
 337         f2fs_balance_fs(sbi);
 338
 339         inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
 340         if (IS_ERR(inode))
 341                 return PTR_ERR(inode);
 342
 343         if (f2fs_encrypted_inode(inode))
 344                 inode->i_op = &f2fs_encrypted_symlink_inode_operations;
 345         else
 346                 inode->i_op = &f2fs_symlink_inode_operations;
 347         inode->i_mapping->a_ops = &f2fs_dblock_aops;
 348
 349         f2fs_lock_op(sbi);
 350         err = f2fs_add_link(dentry, inode);
 351         if (err)
 352                 goto out;
 353         f2fs_unlock_op(sbi);
 354         alloc_nid_done(sbi, inode->i_ino);
 355
 356         if (f2fs_encrypted_inode(dir)) {
 357                 struct qstr istr = QSTR_INIT(symname, len);
 358
 359                 err = f2fs_get_encryption_info(inode);
 360                 if (err)
 361                         goto err_out;
 362
 363                 err = f2fs_fname_crypto_alloc_buffer(inode, len, &disk_link);
 364                 if (err)
 365                         goto err_out;
 366
 367                 err = f2fs_fname_usr_to_disk(inode, &istr, &disk_link);
 368                 if (err < 0)
 369                         goto err_out;
 370
 371                 p_len = encrypted_symlink_data_len(disk_link.len) + 1;
 372
 373                 if (p_len > dir->i_sb->s_blocksize) {
 374                         err = -ENAMETOOLONG;
 375                         goto err_out;
 376                 }
 377
 378                 sd = kzalloc(p_len, GFP_NOFS);
 379                 if (!sd) {
 380                         err = -ENOMEM;
 381                         goto err_out;
 382                 }
 383                 memcpy(sd->encrypted_path, disk_link.name, disk_link.len);
 384                 sd->len = cpu_to_le16(disk_link.len);
 385                 p_str = (char *)sd;
 386         } else {
 387                 p_len = len + 1;
 388                 p_str = (char *)symname;
 389         }
 390
 391         err = page_symlink(inode, p_str, p_len);
 392
 393 err_out:
 394         d_instantiate(dentry, inode);
 395         unlock_new_inode(inode);
 396
 397         /*
 398          * Let's flush symlink data in order to avoid broken symlink as much as
 399          * possible. Nevertheless, fsyncing is the best way, but there is no
 400          * way to get a file descriptor in order to flush that.
 401          *
 402          * Note that, it needs to do dir->fsync to make this recoverable.
 403          * If the symlink path is stored into inline_data, there is no
 404          * performance regression.
 405          */
 406         if (!err)
 407                 filemap_write_and_wait_range(inode->i_mapping, 0, p_len - 1);
 408
 409         if (IS_DIRSYNC(dir))
 410                 f2fs_sync_fs(sbi->sb, 1);
 411
 412         kfree(sd);
 413         f2fs_fname_crypto_free_buffer(&disk_link);
 414         return err;
 415 out:
 416         handle_failed_inode(inode);
 417         return err;
 418 }
 419
 420 static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 421 {
 422         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 423         struct inode *inode;
 424         int err;
 425
 426         f2fs_balance_fs(sbi);
 427
 428         inode = f2fs_new_inode(dir, S_IFDIR | mode);
 429         if (IS_ERR(inode))
 430                 return PTR_ERR(inode);
 431
 432         inode->i_op = &f2fs_dir_inode_operations;
 433         inode->i_fop = &f2fs_dir_operations;
 434         inode->i_mapping->a_ops = &f2fs_dblock_aops;
 435         mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO);
 436
 437         set_inode_flag(F2FS_I(inode), FI_INC_LINK);
 438         f2fs_lock_op(sbi);
 439         err = f2fs_add_link(dentry, inode);
 440         if (err)
 441                 goto out_fail;
 442         f2fs_unlock_op(sbi);
 443
 444         alloc_nid_done(sbi, inode->i_ino);
 445
 446         d_instantiate(dentry, inode);
 447         unlock_new_inode(inode);
 448
 449         if (IS_DIRSYNC(dir))
 450                 f2fs_sync_fs(sbi->sb, 1);
 451         return 0;
 452
 453 out_fail:
 454         clear_inode_flag(F2FS_I(inode), FI_INC_LINK);
 455         handle_failed_inode(inode);
 456         return err;
 457 }
 458
 459 static int f2fs_rmdir(struct inode *dir, struct dentry *dentry)
 460 {
 461         struct inode *inode = d_inode(dentry);
 462         if (f2fs_empty_dir(inode))
 463                 return f2fs_unlink(dir, dentry);
 464         return -ENOTEMPTY;
 465 }
 466
 467 static int f2fs_mknod(struct inode *dir, struct dentry *dentry,
 468                                 umode_t mode, dev_t rdev)
 469 {
 470         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 471         struct inode *inode;
 472         int err = 0;
 473
 474         if (!new_valid_dev(rdev))
 475                 return -EINVAL;
 476
 477         f2fs_balance_fs(sbi);
 478
 479         inode = f2fs_new_inode(dir, mode);
 480         if (IS_ERR(inode))
 481                 return PTR_ERR(inode);
 482
 483         init_special_inode(inode, inode->i_mode, rdev);
 484         inode->i_op = &f2fs_special_inode_operations;
 485
 486         f2fs_lock_op(sbi);
 487         err = f2fs_add_link(dentry, inode);
 488         if (err)
 489                 goto out;
 490         f2fs_unlock_op(sbi);
 491
 492         alloc_nid_done(sbi, inode->i_ino);
 493
 494         d_instantiate(dentry, inode);
 495         unlock_new_inode(inode);
 496
 497         if (IS_DIRSYNC(dir))
 498                 f2fs_sync_fs(sbi->sb, 1);
 499         return 0;
 500 out:
 501         handle_failed_inode(inode);
 502         return err;
 503 }
 504
 505 static int __f2fs_tmpfile(struct inode *dir, struct dentry *dentry,
 506                                         umode_t mode, struct inode **whiteout)
 507 {
 508         struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
 509         struct inode *inode;
 510         int err;
 511
 512         if (!whiteout)
 513                 f2fs_balance_fs(sbi);
 514
 515         inode = f2fs_new_inode(dir, mode);
 516         if (IS_ERR(inode))
 517                 return PTR_ERR(inode);
 518
 519         if (whiteout) {
 520                 init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
 521                 inode->i_op = &f2fs_special_inode_operations;
 522         } else {
 523                 inode->i_op = &f2fs_file_inode_operations;
 524                 inode->i_fop = &f2fs_file_operations;
 525                 inode->i_mapping->a_ops = &f2fs_dblock_aops;
 526         }
 527
 528         f2fs_lock_op(sbi);
 529         err = acquire_orphan_inode(sbi);
 530         if (err)
 531                 goto out;
 532
 533         err = f2fs_do_tmpfile(inode, dir);
 534         if (err)
 535                 goto release_out;
 536
 537         /*
 538          * add this non-linked tmpfile to orphan list, in this way we could
 539          * remove all unused data of tmpfile after abnormal power-off.
 540          */
 541         add_orphan_inode(sbi, inode->i_ino);
 542         f2fs_unlock_op(sbi);
 543
 544         alloc_nid_done(sbi, inode->i_ino);
 545
 546         if (whiteout) {
 547                 inode_dec_link_count(inode);
 548                 *whiteout = inode;
 549         } else {
 550                 d_tmpfile(dentry, inode);
 551         }
 552         unlock_new_inode(inode);
 553         return 0;
 554
 555 release_out:
 556         release_orphan_inode(sbi);
 557 out:
 558         handle_failed_inode(inode);
 559         return err;
 560 }
 561
 562 static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 563 {
 564         if (f2fs_encrypted_inode(dir)) {
 565                 int err = f2fs_get_encryption_info(dir);
 566                 if (err)
 567                         return err;
 568         }
 569
 570         return __f2fs_tmpfile(dir, dentry, mode, NULL);
 571 }
 572
 573 static int f2fs_create_whiteout(struct inode *dir, struct inode **whiteout)
 574 {
 575         return __f2fs_tmpfile(dir, NULL, S_IFCHR | WHITEOUT_MODE, whiteout);
 576 }
 577
 578 static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
 579                         struct inode *new_dir, struct dentry *new_dentry,
 580                         unsigned int flags)
 581 {
 582         struct f2fs_sb_info *sbi = F2FS_I_SB(old_dir);
 583         struct inode *old_inode = d_inode(old_dentry);
 584         struct inode *new_inode = d_inode(new_dentry);
 585         struct inode *whiteout = NULL;
 586         struct page *old_dir_page;
 587         struct page *old_page, *new_page = NULL;
 588         struct f2fs_dir_entry *old_dir_entry = NULL;
 589         struct f2fs_dir_entry *old_entry;
 590         struct f2fs_dir_entry *new_entry;
 591         int err = -ENOENT;
 592
 593         if ((old_dir != new_dir) && f2fs_encrypted_inode(new_dir) &&
 594                 !f2fs_is_child_context_consistent_with_parent(new_dir,
 595                                                         old_inode)) {
 596                 err = -EPERM;
 597                 goto out;
 598         }
 599
 600         f2fs_balance_fs(sbi);
 601
 602         old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
 603         if (!old_entry)
 604                 goto out;
 605
 606         if (S_ISDIR(old_inode->i_mode)) {
 607                 err = -EIO;
 608                 old_dir_entry = f2fs_parent_dir(old_inode, &old_dir_page);
 609                 if (!old_dir_entry)
 610                         goto out_old;
 611         }
 612
 613         if (flags & RENAME_WHITEOUT) {
 614                 err = f2fs_create_whiteout(old_dir, &whiteout);
 615                 if (err)
 616                         goto out_dir;
 617         }
 618
 619         if (new_inode) {
 620
 621                 err = -ENOTEMPTY;
 622                 if (old_dir_entry && !f2fs_empty_dir(new_inode))
 623                         goto out_whiteout;
 624
 625                 err = -ENOENT;
 626                 new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name,
 627                                                 &new_page);
 628                 if (!new_entry)
 629                         goto out_whiteout;
 630
 631                 f2fs_lock_op(sbi);
 632
 633                 err = acquire_orphan_inode(sbi);
 634                 if (err)
 635                         goto put_out_dir;
 636
 637                 if (update_dent_inode(old_inode, new_inode,
 638                                                 &new_dentry->d_name)) {
 639                         release_orphan_inode(sbi);
 640                         goto put_out_dir;
 641                 }
 642
 643                 f2fs_set_link(new_dir, new_entry, new_page, old_inode);
 644
 645                 new_inode->i_ctime = CURRENT_TIME;
 646                 down_write(&F2FS_I(new_inode)->i_sem);
 647                 if (old_dir_entry)
 648                         drop_nlink(new_inode);
 649                 drop_nlink(new_inode);
 650                 up_write(&F2FS_I(new_inode)->i_sem);
 651
 652                 mark_inode_dirty(new_inode);
 653
 654                 if (!new_inode->i_nlink)
 655                         add_orphan_inode(sbi, new_inode->i_ino);
 656                 else
 657                         release_orphan_inode(sbi);
 658
 659                 update_inode_page(old_inode);
 660                 update_inode_page(new_inode);
 661         } else {
 662                 f2fs_lock_op(sbi);
 663
 664                 err = f2fs_add_link(new_dentry, old_inode);
 665                 if (err) {
 666                         f2fs_unlock_op(sbi);
 667                         goto out_whiteout;
 668                 }
 669
 670                 if (old_dir_entry) {
 671                         inc_nlink(new_dir);
 672                         update_inode_page(new_dir);
 673                 }
 674         }
 675
 676         down_write(&F2FS_I(old_inode)->i_sem);
 677         file_lost_pino(old_inode);
 678         if (new_inode && file_enc_name(new_inode))
 679                 file_set_enc_name(old_inode);
 680         up_write(&F2FS_I(old_inode)->i_sem);
 681
 682         old_inode->i_ctime = CURRENT_TIME;
 683         mark_inode_dirty(old_inode);
 684
 685         f2fs_delete_entry(old_entry, old_page, old_dir, NULL);
 686
 687         if (whiteout) {
 688                 whiteout->i_state |= I_LINKABLE;
 689                 set_inode_flag(F2FS_I(whiteout), FI_INC_LINK);
 690                 err = f2fs_add_link(old_dentry, whiteout);
 691                 if (err)
 692                         goto put_out_dir;
 693                 whiteout->i_state &= ~I_LINKABLE;
 694                 iput(whiteout);
 695         }
 696
 697         if (old_dir_entry) {
 698                 if (old_dir != new_dir && !whiteout) {
 699                         f2fs_set_link(old_inode, old_dir_entry,
 700                                                 old_dir_page, new_dir);
 701                         update_inode_page(old_inode);
 702                 } else {
 703                         f2fs_dentry_kunmap(old_inode, old_dir_page);
 704                         f2fs_put_page(old_dir_page, 0);
 705                 }
 706                 drop_nlink(old_dir);
 707                 mark_inode_dirty(old_dir);
 708                 update_inode_page(old_dir);
 709         }
 710
 711         f2fs_unlock_op(sbi);
 712
 713         if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
 714                 f2fs_sync_fs(sbi->sb, 1);
 715         return 0;
 716
 717 put_out_dir:
 718         f2fs_unlock_op(sbi);
 719         if (new_page) {
 720                 f2fs_dentry_kunmap(new_dir, new_page);
 721                 f2fs_put_page(new_page, 0);
 722         }
 723 out_whiteout:
 724         if (whiteout)
 725                 iput(whiteout);
 726 out_dir:
 727         if (old_dir_entry) {
 728                 f2fs_dentry_kunmap(old_inode, old_dir_page);
 729                 f2fs_put_page(old_dir_page, 0);
 730         }
 731 out_old:
 732         f2fs_dentry_kunmap(old_dir, old_page);
 733         f2fs_put_page(old_page, 0);
 734 out:
 735         return err;
 736 }
 737
 738 static int f2fs_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
 739                              struct inode *new_dir, struct dentry *new_dentry)
 740 {
 741         struct f2fs_sb_info *sbi = F2FS_I_SB(old_dir);
 742         struct inode *old_inode = d_inode(old_dentry);
 743         struct inode *new_inode = d_inode(new_dentry);
 744         struct page *old_dir_page, *new_dir_page;
 745         struct page *old_page, *new_page;
 746         struct f2fs_dir_entry *old_dir_entry = NULL, *new_dir_entry = NULL;
 747         struct f2fs_dir_entry *old_entry, *new_entry;
 748         int old_nlink = 0, new_nlink = 0;
 749         int err = -ENOENT;
 750
 751         if ((f2fs_encrypted_inode(old_dir) || f2fs_encrypted_inode(new_dir)) &&
 752                 (old_dir != new_dir) &&
 753                 (!f2fs_is_child_context_consistent_with_parent(new_dir,
 754                                                                 old_inode) ||
 755                 !f2fs_is_child_context_consistent_with_parent(old_dir,
 756                                                                 new_inode)))
 757                 return -EPERM;
 758
 759         f2fs_balance_fs(sbi);
 760
 761         old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
 762         if (!old_entry)
 763                 goto out;
 764
 765         new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name, &new_page);
 766         if (!new_entry)
 767                 goto out_old;
 768
 769         /* prepare for updating ".." directory entry info later */
 770         if (old_dir != new_dir) {
 771                 if (S_ISDIR(old_inode->i_mode)) {
 772                         err = -EIO;
 773                         old_dir_entry = f2fs_parent_dir(old_inode,
 774                                                         &old_dir_page);
 775                         if (!old_dir_entry)
 776                                 goto out_new;
 777                 }
 778
 779                 if (S_ISDIR(new_inode->i_mode)) {
 780                         err = -EIO;
 781                         new_dir_entry = f2fs_parent_dir(new_inode,
 782                                                         &new_dir_page);
 783                         if (!new_dir_entry)
 784                                 goto out_old_dir;
 785                 }
 786         }
 787
 788         /*
 789          * If cross rename between file and directory those are not
 790          * in the same directory, we will inc nlink of file's parent
 791          * later, so we should check upper boundary of its nlink.
 792          */
 793         if ((!old_dir_entry || !new_dir_entry) &&
 794                                 old_dir_entry != new_dir_entry) {
 795                 old_nlink = old_dir_entry ? -1 : 1;
 796                 new_nlink = -old_nlink;
 797                 err = -EMLINK;
 798                 if ((old_nlink > 0 && old_inode->i_nlink >= F2FS_LINK_MAX) ||
 799                         (new_nlink > 0 && new_inode->i_nlink >= F2FS_LINK_MAX))
 800                         goto out_new_dir;
 801         }
 802
 803         f2fs_lock_op(sbi);
 804
 805         err = update_dent_inode(old_inode, new_inode, &new_dentry->d_name);
 806         if (err)
 807                 goto out_unlock;
 808         if (file_enc_name(new_inode))
 809                 file_set_enc_name(old_inode);
 810
 811         err = update_dent_inode(new_inode, old_inode, &old_dentry->d_name);
 812         if (err)
 813                 goto out_undo;
 814         if (file_enc_name(old_inode))
 815                 file_set_enc_name(new_inode);
 816
 817         /* update ".." directory entry info of old dentry */
 818         if (old_dir_entry)
 819                 f2fs_set_link(old_inode, old_dir_entry, old_dir_page, new_dir);
 820
 821         /* update ".." directory entry info of new dentry */
 822         if (new_dir_entry)
 823                 f2fs_set_link(new_inode, new_dir_entry, new_dir_page, old_dir);
 824
 825         /* update directory entry info of old dir inode */
 826         f2fs_set_link(old_dir, old_entry, old_page, new_inode);
 827
 828         down_write(&F2FS_I(old_inode)->i_sem);
 829         file_lost_pino(old_inode);
 830         up_write(&F2FS_I(old_inode)->i_sem);
 831
 832         update_inode_page(old_inode);
 833
 834         old_dir->i_ctime = CURRENT_TIME;
 835         if (old_nlink) {
 836                 down_write(&F2FS_I(old_dir)->i_sem);
 837                 if (old_nlink < 0)
 838                         drop_nlink(old_dir);
 839                 else
 840                         inc_nlink(old_dir);
 841                 up_write(&F2FS_I(old_dir)->i_sem);
 842         }
 843         mark_inode_dirty(old_dir);
 844         update_inode_page(old_dir);
 845
 846         /* update directory entry info of new dir inode */
 847         f2fs_set_link(new_dir, new_entry, new_page, old_inode);
 848
 849         down_write(&F2FS_I(new_inode)->i_sem);
 850         file_lost_pino(new_inode);
 851         up_write(&F2FS_I(new_inode)->i_sem);
 852
 853         update_inode_page(new_inode);
 854
 855         new_dir->i_ctime = CURRENT_TIME;
 856         if (new_nlink) {
 857                 down_write(&F2FS_I(new_dir)->i_sem);
 858                 if (new_nlink < 0)
 859                         drop_nlink(new_dir);
 860                 else
 861                         inc_nlink(new_dir);
 862                 up_write(&F2FS_I(new_dir)->i_sem);
 863         }
 864         mark_inode_dirty(new_dir);
 865         update_inode_page(new_dir);
 866
 867         f2fs_unlock_op(sbi);
 868
 869         if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
 870                 f2fs_sync_fs(sbi->sb, 1);
 871         return 0;
 872 out_undo:
 873         /*
 874          * Still we may fail to recover name info of f2fs_inode here
 875          * Drop it, once its name is set as encrypted
 876          */
 877         update_dent_inode(old_inode, old_inode, &old_dentry->d_name);
 878 out_unlock:
 879         f2fs_unlock_op(sbi);
 880 out_new_dir:
 881         if (new_dir_entry) {
 882                 f2fs_dentry_kunmap(new_inode, new_dir_page);
 883                 f2fs_put_page(new_dir_page, 0);
 884         }
 885 out_old_dir:
 886         if (old_dir_entry) {
 887                 f2fs_dentry_kunmap(old_inode, old_dir_page);
 888                 f2fs_put_page(old_dir_page, 0);
 889         }
 890 out_new:
 891         f2fs_dentry_kunmap(new_dir, new_page);
 892         f2fs_put_page(new_page, 0);
 893 out_old:
 894         f2fs_dentry_kunmap(old_dir, old_page);
 895         f2fs_put_page(old_page, 0);
 896 out:
 897         return err;
 898 }
 899
 900 static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry,
 901                         struct inode *new_dir, struct dentry *new_dentry,
 902                         unsigned int flags)
 903 {
 904         if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
 905                 return -EINVAL;
 906
 907         if (flags & RENAME_EXCHANGE) {
 908                 return f2fs_cross_rename(old_dir, old_dentry,
 909                                          new_dir, new_dentry);
 910         }
 911         /*
 912          * VFS has already handled the new dentry existence case,
 913          * here, we just deal with "RENAME_NOREPLACE" as regular rename.
 914          */
 915         return f2fs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
 916 }
 917
 918 #ifdef CONFIG_F2FS_FS_ENCRYPTION
 919 static const char *f2fs_encrypted_follow_link(struct dentry *dentry, void **cookie)
 920 {
 921         struct page *cpage = NULL;
 922         char *caddr, *paddr = NULL;
 923         struct f2fs_str cstr;
 924         struct f2fs_str pstr = FSTR_INIT(NULL, 0);
 925         struct inode *inode = d_inode(dentry);
 926         struct f2fs_encrypted_symlink_data *sd;
 927         loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
 928         u32 max_size = inode->i_sb->s_blocksize;
 929         int res;
 930
 931         res = f2fs_get_encryption_info(inode);
 932         if (res)
 933                 return ERR_PTR(res);
 934
 935         cpage = read_mapping_page(inode->i_mapping, 0, NULL);
 936         if (IS_ERR(cpage))
 937                 return ERR_CAST(cpage);
 938         caddr = kmap(cpage);
 939         caddr[size] = 0;
 940
 941         /* Symlink is encrypted */
 942         sd = (struct f2fs_encrypted_symlink_data *)caddr;
 943         cstr.name = sd->encrypted_path;
 944         cstr.len = le16_to_cpu(sd->len);
 945
 946         /* this is broken symlink case */
 947         if (cstr.name[0] == 0 && cstr.len == 0) {
 948                 res = -ENOENT;
 949                 goto errout;
 950         }
 951
 952         if ((cstr.len + sizeof(struct f2fs_encrypted_symlink_data) - 1) >
 953                                                                 max_size) {
 954                 /* Symlink data on the disk is corrupted */
 955                 res = -EIO;
 956                 goto errout;
 957         }
 958         res = f2fs_fname_crypto_alloc_buffer(inode, cstr.len, &pstr);
 959         if (res)
 960                 goto errout;
 961
 962         res = f2fs_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
 963         if (res < 0)
 964                 goto errout;
 965
 966         paddr = pstr.name;
 967
 968         /* Null-terminate the name */
 969         paddr[res] = '\0';
 970
 971         kunmap(cpage);
 972         page_cache_release(cpage);
 973         return *cookie = paddr;
 974 errout:
 975         f2fs_fname_crypto_free_buffer(&pstr);
 976         kunmap(cpage);
 977         page_cache_release(cpage);
 978         return ERR_PTR(res);
 979 }
 980
 981 const struct inode_operations f2fs_encrypted_symlink_inode_operations = {
 982         .readlink       = generic_readlink,
 983         .follow_link    = f2fs_encrypted_follow_link,
 984         .put_link       = kfree_put_link,
 985         .getattr        = f2fs_getattr,
 986         .setattr        = f2fs_setattr,
 987         .setxattr       = generic_setxattr,
 988         .getxattr       = generic_getxattr,
 989         .listxattr      = f2fs_listxattr,
 990         .removexattr    = generic_removexattr,
 991 };
 992 #endif
 993
 994 const struct inode_operations f2fs_dir_inode_operations = {
 995         .create         = f2fs_create,
 996         .lookup         = f2fs_lookup,
 997         .link           = f2fs_link,
 998         .unlink         = f2fs_unlink,
 999         .symlink        = f2fs_symlink,
1000         .mkdir          = f2fs_mkdir,
1001         .rmdir          = f2fs_rmdir,
1002         .mknod          = f2fs_mknod,
1003         .rename2        = f2fs_rename2,
1004         .tmpfile        = f2fs_tmpfile,
1005         .getattr        = f2fs_getattr,
1006         .setattr        = f2fs_setattr,
1007         .get_acl        = f2fs_get_acl,
1008         .set_acl        = f2fs_set_acl,
1009 #ifdef CONFIG_F2FS_FS_XATTR
1010         .setxattr       = generic_setxattr,
1011         .getxattr       = generic_getxattr,
1012         .listxattr      = f2fs_listxattr,
1013         .removexattr    = generic_removexattr,
1014 #endif
1015 };
1016
1017 const struct inode_operations f2fs_symlink_inode_operations = {
1018         .readlink       = generic_readlink,
1019         .follow_link    = f2fs_follow_link,
1020         .put_link       = page_put_link,
1021         .getattr        = f2fs_getattr,
1022         .setattr        = f2fs_setattr,
1023 #ifdef CONFIG_F2FS_FS_XATTR
1024         .setxattr       = generic_setxattr,
1025         .getxattr       = generic_getxattr,
1026         .listxattr      = f2fs_listxattr,
1027         .removexattr    = generic_removexattr,
1028 #endif
1029 };
1030
1031 const struct inode_operations f2fs_special_inode_operations = {
1032         .getattr        = f2fs_getattr,
1033         .setattr        = f2fs_setattr,
1034         .get_acl        = f2fs_get_acl,
1035         .set_acl        = f2fs_set_acl,
1036 #ifdef CONFIG_F2FS_FS_XATTR
1037         .setxattr       = generic_setxattr,
1038         .getxattr       = generic_getxattr,
1039         .listxattr      = f2fs_listxattr,
1040         .removexattr    = generic_removexattr,
1041 #endif
1042 };