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1// SPDX-License-Identifier: GPL-2.02/*3 * fs/f2fs/dir.c4 *5 * Copyright (c) 2012 Samsung Electronics Co., Ltd.6 * http://www.samsung.com/7 */8#include <linux/unaligned.h>9#include <linux/fs.h>10#include <linux/f2fs_fs.h>11#include <linux/sched/signal.h>12#include <linux/unicode.h>13#include "f2fs.h"14#include "node.h"15#include "acl.h"16#include "xattr.h"17#include <trace/events/f2fs.h>18 19#if IS_ENABLED(CONFIG_UNICODE)20extern struct kmem_cache *f2fs_cf_name_slab;21#endif22 23static unsigned long dir_blocks(struct inode *inode)24{25 return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))26 >> PAGE_SHIFT;27}28 29static unsigned int dir_buckets(unsigned int level, int dir_level)30{31 if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)32 return BIT(level + dir_level);33 else34 return MAX_DIR_BUCKETS;35}36 37static unsigned int bucket_blocks(unsigned int level)38{39 if (level < MAX_DIR_HASH_DEPTH / 2)40 return 2;41 else42 return 4;43}44 45#if IS_ENABLED(CONFIG_UNICODE)46/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */47int f2fs_init_casefolded_name(const struct inode *dir,48 struct f2fs_filename *fname)49{50 struct super_block *sb = dir->i_sb;51 unsigned char *buf;52 int len;53 54 if (IS_CASEFOLDED(dir) &&55 !is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {56 buf = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,57 GFP_NOFS, false, F2FS_SB(sb));58 if (!buf)59 return -ENOMEM;60 61 len = utf8_casefold(sb->s_encoding, fname->usr_fname,62 buf, F2FS_NAME_LEN);63 if (len <= 0) {64 kmem_cache_free(f2fs_cf_name_slab, buf);65 if (sb_has_strict_encoding(sb))66 return -EINVAL;67 /* fall back to treating name as opaque byte sequence */68 return 0;69 }70 fname->cf_name.name = buf;71 fname->cf_name.len = len;72 }73 74 return 0;75}76 77void f2fs_free_casefolded_name(struct f2fs_filename *fname)78{79 unsigned char *buf = (unsigned char *)fname->cf_name.name;80 81 if (buf) {82 kmem_cache_free(f2fs_cf_name_slab, buf);83 fname->cf_name.name = NULL;84 }85}86#endif /* CONFIG_UNICODE */87 88static int __f2fs_setup_filename(const struct inode *dir,89 const struct fscrypt_name *crypt_name,90 struct f2fs_filename *fname)91{92 int err;93 94 memset(fname, 0, sizeof(*fname));95 96 fname->usr_fname = crypt_name->usr_fname;97 fname->disk_name = crypt_name->disk_name;98#ifdef CONFIG_FS_ENCRYPTION99 fname->crypto_buf = crypt_name->crypto_buf;100#endif101 if (crypt_name->is_nokey_name) {102 /* hash was decoded from the no-key name */103 fname->hash = cpu_to_le32(crypt_name->hash);104 } else {105 err = f2fs_init_casefolded_name(dir, fname);106 if (err) {107 f2fs_free_filename(fname);108 return err;109 }110 f2fs_hash_filename(dir, fname);111 }112 return 0;113}114 115/*116 * Prepare to search for @iname in @dir. This is similar to117 * fscrypt_setup_filename(), but this also handles computing the casefolded name118 * and the f2fs dirhash if needed, then packing all the information about this119 * filename up into a 'struct f2fs_filename'.120 */121int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,122 int lookup, struct f2fs_filename *fname)123{124 struct fscrypt_name crypt_name;125 int err;126 127 err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);128 if (err)129 return err;130 131 return __f2fs_setup_filename(dir, &crypt_name, fname);132}133 134/*135 * Prepare to look up @dentry in @dir. This is similar to136 * fscrypt_prepare_lookup(), but this also handles computing the casefolded name137 * and the f2fs dirhash if needed, then packing all the information about this138 * filename up into a 'struct f2fs_filename'.139 */140int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,141 struct f2fs_filename *fname)142{143 struct fscrypt_name crypt_name;144 int err;145 146 err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);147 if (err)148 return err;149 150 return __f2fs_setup_filename(dir, &crypt_name, fname);151}152 153void f2fs_free_filename(struct f2fs_filename *fname)154{155#ifdef CONFIG_FS_ENCRYPTION156 kfree(fname->crypto_buf.name);157 fname->crypto_buf.name = NULL;158#endif159 f2fs_free_casefolded_name(fname);160}161 162static unsigned long dir_block_index(unsigned int level,163 int dir_level, unsigned int idx)164{165 unsigned long i;166 unsigned long bidx = 0;167 168 for (i = 0; i < level; i++)169 bidx += mul_u32_u32(dir_buckets(i, dir_level),170 bucket_blocks(i));171 bidx += idx * bucket_blocks(level);172 return bidx;173}174 175static struct f2fs_dir_entry *find_in_block(struct inode *dir,176 struct page *dentry_page,177 const struct f2fs_filename *fname,178 int *max_slots)179{180 struct f2fs_dentry_block *dentry_blk;181 struct f2fs_dentry_ptr d;182 183 dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);184 185 make_dentry_ptr_block(dir, &d, dentry_blk);186 return f2fs_find_target_dentry(&d, fname, max_slots);187}188 189static inline int f2fs_match_name(const struct inode *dir,190 const struct f2fs_filename *fname,191 const u8 *de_name, u32 de_name_len)192{193 struct fscrypt_name f;194 195#if IS_ENABLED(CONFIG_UNICODE)196 if (fname->cf_name.name)197 return generic_ci_match(dir, fname->usr_fname,198 &fname->cf_name,199 de_name, de_name_len);200 201#endif202 f.usr_fname = fname->usr_fname;203 f.disk_name = fname->disk_name;204#ifdef CONFIG_FS_ENCRYPTION205 f.crypto_buf = fname->crypto_buf;206#endif207 return fscrypt_match_name(&f, de_name, de_name_len);208}209 210struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,211 const struct f2fs_filename *fname, int *max_slots)212{213 struct f2fs_dir_entry *de;214 unsigned long bit_pos = 0;215 int max_len = 0;216 int res = 0;217 218 if (max_slots)219 *max_slots = 0;220 while (bit_pos < d->max) {221 if (!test_bit_le(bit_pos, d->bitmap)) {222 bit_pos++;223 max_len++;224 continue;225 }226 227 de = &d->dentry[bit_pos];228 229 if (unlikely(!de->name_len)) {230 bit_pos++;231 continue;232 }233 234 if (de->hash_code == fname->hash) {235 res = f2fs_match_name(d->inode, fname,236 d->filename[bit_pos],237 le16_to_cpu(de->name_len));238 if (res < 0)239 return ERR_PTR(res);240 if (res)241 goto found;242 }243 244 if (max_slots && max_len > *max_slots)245 *max_slots = max_len;246 max_len = 0;247 248 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));249 }250 251 de = NULL;252found:253 if (max_slots && max_len > *max_slots)254 *max_slots = max_len;255 return de;256}257 258static struct f2fs_dir_entry *find_in_level(struct inode *dir,259 unsigned int level,260 const struct f2fs_filename *fname,261 struct page **res_page)262{263 int s = GET_DENTRY_SLOTS(fname->disk_name.len);264 unsigned int nbucket, nblock;265 unsigned int bidx, end_block;266 struct page *dentry_page;267 struct f2fs_dir_entry *de = NULL;268 pgoff_t next_pgofs;269 bool room = false;270 int max_slots;271 272 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);273 nblock = bucket_blocks(level);274 275 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,276 le32_to_cpu(fname->hash) % nbucket);277 end_block = bidx + nblock;278 279 while (bidx < end_block) {280 /* no need to allocate new dentry pages to all the indices */281 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);282 if (IS_ERR(dentry_page)) {283 if (PTR_ERR(dentry_page) == -ENOENT) {284 room = true;285 bidx = next_pgofs;286 continue;287 } else {288 *res_page = dentry_page;289 break;290 }291 }292 293 de = find_in_block(dir, dentry_page, fname, &max_slots);294 if (IS_ERR(de)) {295 *res_page = ERR_CAST(de);296 de = NULL;297 break;298 } else if (de) {299 *res_page = dentry_page;300 break;301 }302 303 if (max_slots >= s)304 room = true;305 f2fs_put_page(dentry_page, 0);306 307 bidx++;308 }309 310 if (!de && room && F2FS_I(dir)->chash != fname->hash) {311 F2FS_I(dir)->chash = fname->hash;312 F2FS_I(dir)->clevel = level;313 }314 315 return de;316}317 318struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,319 const struct f2fs_filename *fname,320 struct page **res_page)321{322 unsigned long npages = dir_blocks(dir);323 struct f2fs_dir_entry *de = NULL;324 unsigned int max_depth;325 unsigned int level;326 327 *res_page = NULL;328 329 if (f2fs_has_inline_dentry(dir)) {330 de = f2fs_find_in_inline_dir(dir, fname, res_page);331 goto out;332 }333 334 if (npages == 0)335 goto out;336 337 max_depth = F2FS_I(dir)->i_current_depth;338 if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {339 f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",340 dir->i_ino, max_depth);341 max_depth = MAX_DIR_HASH_DEPTH;342 f2fs_i_depth_write(dir, max_depth);343 }344 345 for (level = 0; level < max_depth; level++) {346 de = find_in_level(dir, level, fname, res_page);347 if (de || IS_ERR(*res_page))348 break;349 }350out:351 /* This is to increase the speed of f2fs_create */352 if (!de)353 F2FS_I(dir)->task = current;354 return de;355}356 357/*358 * Find an entry in the specified directory with the wanted name.359 * It returns the page where the entry was found (as a parameter - res_page),360 * and the entry itself. Page is returned mapped and unlocked.361 * Entry is guaranteed to be valid.362 */363struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,364 const struct qstr *child, struct page **res_page)365{366 struct f2fs_dir_entry *de = NULL;367 struct f2fs_filename fname;368 int err;369 370 err = f2fs_setup_filename(dir, child, 1, &fname);371 if (err) {372 if (err == -ENOENT)373 *res_page = NULL;374 else375 *res_page = ERR_PTR(err);376 return NULL;377 }378 379 de = __f2fs_find_entry(dir, &fname, res_page);380 381 f2fs_free_filename(&fname);382 return de;383}384 385struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)386{387 return f2fs_find_entry(dir, &dotdot_name, p);388}389 390ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,391 struct page **page)392{393 ino_t res = 0;394 struct f2fs_dir_entry *de;395 396 de = f2fs_find_entry(dir, qstr, page);397 if (de) {398 res = le32_to_cpu(de->ino);399 f2fs_put_page(*page, 0);400 }401 402 return res;403}404 405void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,406 struct page *page, struct inode *inode)407{408 enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;409 410 lock_page(page);411 f2fs_wait_on_page_writeback(page, type, true, true);412 de->ino = cpu_to_le32(inode->i_ino);413 de->file_type = fs_umode_to_ftype(inode->i_mode);414 set_page_dirty(page);415 416 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));417 f2fs_mark_inode_dirty_sync(dir, false);418 f2fs_put_page(page, 1);419}420 421static void init_dent_inode(struct inode *dir, struct inode *inode,422 const struct f2fs_filename *fname,423 struct page *ipage)424{425 struct f2fs_inode *ri;426 427 if (!fname) /* tmpfile case? */428 return;429 430 f2fs_wait_on_page_writeback(ipage, NODE, true, true);431 432 /* copy name info. to this inode page */433 ri = F2FS_INODE(ipage);434 ri->i_namelen = cpu_to_le32(fname->disk_name.len);435 memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);436 if (IS_ENCRYPTED(dir)) {437 file_set_enc_name(inode);438 /*439 * Roll-forward recovery doesn't have encryption keys available,440 * so it can't compute the dirhash for encrypted+casefolded441 * filenames. Append it to i_name if possible. Else, disable442 * roll-forward recovery of the dentry (i.e., make fsync'ing the443 * file force a checkpoint) by setting LOST_PINO.444 */445 if (IS_CASEFOLDED(dir)) {446 if (fname->disk_name.len + sizeof(f2fs_hash_t) <=447 F2FS_NAME_LEN)448 put_unaligned(fname->hash, (f2fs_hash_t *)449 &ri->i_name[fname->disk_name.len]);450 else451 file_lost_pino(inode);452 }453 }454 set_page_dirty(ipage);455}456 457void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,458 struct f2fs_dentry_ptr *d)459{460 struct fscrypt_str dot = FSTR_INIT(".", 1);461 struct fscrypt_str dotdot = FSTR_INIT("..", 2);462 463 /* update dirent of "." */464 f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);465 466 /* update dirent of ".." */467 f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);468}469 470static int make_empty_dir(struct inode *inode,471 struct inode *parent, struct page *page)472{473 struct page *dentry_page;474 struct f2fs_dentry_block *dentry_blk;475 struct f2fs_dentry_ptr d;476 477 if (f2fs_has_inline_dentry(inode))478 return f2fs_make_empty_inline_dir(inode, parent, page);479 480 dentry_page = f2fs_get_new_data_page(inode, page, 0, true);481 if (IS_ERR(dentry_page))482 return PTR_ERR(dentry_page);483 484 dentry_blk = page_address(dentry_page);485 486 make_dentry_ptr_block(NULL, &d, dentry_blk);487 f2fs_do_make_empty_dir(inode, parent, &d);488 489 set_page_dirty(dentry_page);490 f2fs_put_page(dentry_page, 1);491 return 0;492}493 494struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,495 const struct f2fs_filename *fname, struct page *dpage)496{497 struct page *page;498 int err;499 500 if (is_inode_flag_set(inode, FI_NEW_INODE)) {501 page = f2fs_new_inode_page(inode);502 if (IS_ERR(page))503 return page;504 505 if (S_ISDIR(inode->i_mode)) {506 /* in order to handle error case */507 get_page(page);508 err = make_empty_dir(inode, dir, page);509 if (err) {510 lock_page(page);511 goto put_error;512 }513 put_page(page);514 }515 516 err = f2fs_init_acl(inode, dir, page, dpage);517 if (err)518 goto put_error;519 520 err = f2fs_init_security(inode, dir,521 fname ? fname->usr_fname : NULL, page);522 if (err)523 goto put_error;524 525 if (IS_ENCRYPTED(inode)) {526 err = fscrypt_set_context(inode, page);527 if (err)528 goto put_error;529 }530 } else {531 page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);532 if (IS_ERR(page))533 return page;534 }535 536 init_dent_inode(dir, inode, fname, page);537 538 /*539 * This file should be checkpointed during fsync.540 * We lost i_pino from now on.541 */542 if (is_inode_flag_set(inode, FI_INC_LINK)) {543 if (!S_ISDIR(inode->i_mode))544 file_lost_pino(inode);545 /*546 * If link the tmpfile to alias through linkat path,547 * we should remove this inode from orphan list.548 */549 if (inode->i_nlink == 0)550 f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);551 f2fs_i_links_write(inode, true);552 }553 return page;554 555put_error:556 clear_nlink(inode);557 f2fs_update_inode(inode, page);558 f2fs_put_page(page, 1);559 return ERR_PTR(err);560}561 562void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,563 unsigned int current_depth)564{565 if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {566 if (S_ISDIR(inode->i_mode))567 f2fs_i_links_write(dir, true);568 clear_inode_flag(inode, FI_NEW_INODE);569 }570 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));571 f2fs_mark_inode_dirty_sync(dir, false);572 573 if (F2FS_I(dir)->i_current_depth != current_depth)574 f2fs_i_depth_write(dir, current_depth);575 576 if (inode && is_inode_flag_set(inode, FI_INC_LINK))577 clear_inode_flag(inode, FI_INC_LINK);578}579 580int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)581{582 int bit_start = 0;583 int zero_start, zero_end;584next:585 zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);586 if (zero_start >= max_slots)587 return max_slots;588 589 zero_end = find_next_bit_le(bitmap, max_slots, zero_start);590 if (zero_end - zero_start >= slots)591 return zero_start;592 593 bit_start = zero_end + 1;594 595 if (zero_end + 1 >= max_slots)596 return max_slots;597 goto next;598}599 600bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,601 const struct f2fs_filename *fname)602{603 struct f2fs_dentry_ptr d;604 unsigned int bit_pos;605 int slots = GET_DENTRY_SLOTS(fname->disk_name.len);606 607 make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));608 609 bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);610 611 return bit_pos < d.max;612}613 614void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,615 const struct fscrypt_str *name, f2fs_hash_t name_hash,616 unsigned int bit_pos)617{618 struct f2fs_dir_entry *de;619 int slots = GET_DENTRY_SLOTS(name->len);620 int i;621 622 de = &d->dentry[bit_pos];623 de->hash_code = name_hash;624 de->name_len = cpu_to_le16(name->len);625 memcpy(d->filename[bit_pos], name->name, name->len);626 de->ino = cpu_to_le32(ino);627 de->file_type = fs_umode_to_ftype(mode);628 for (i = 0; i < slots; i++) {629 __set_bit_le(bit_pos + i, (void *)d->bitmap);630 /* avoid wrong garbage data for readdir */631 if (i)632 (de + i)->name_len = 0;633 }634}635 636int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,637 struct inode *inode, nid_t ino, umode_t mode)638{639 unsigned int bit_pos;640 unsigned int level;641 unsigned int current_depth;642 unsigned long bidx, block;643 unsigned int nbucket, nblock;644 struct page *dentry_page = NULL;645 struct f2fs_dentry_block *dentry_blk = NULL;646 struct f2fs_dentry_ptr d;647 struct page *page = NULL;648 int slots, err = 0;649 650 level = 0;651 slots = GET_DENTRY_SLOTS(fname->disk_name.len);652 653 current_depth = F2FS_I(dir)->i_current_depth;654 if (F2FS_I(dir)->chash == fname->hash) {655 level = F2FS_I(dir)->clevel;656 F2FS_I(dir)->chash = 0;657 }658 659start:660 if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH))661 return -ENOSPC;662 663 if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))664 return -ENOSPC;665 666 /* Increase the depth, if required */667 if (level == current_depth)668 ++current_depth;669 670 nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);671 nblock = bucket_blocks(level);672 673 bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,674 (le32_to_cpu(fname->hash) % nbucket));675 676 for (block = bidx; block <= (bidx + nblock - 1); block++) {677 dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);678 if (IS_ERR(dentry_page))679 return PTR_ERR(dentry_page);680 681 dentry_blk = page_address(dentry_page);682 bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,683 slots, NR_DENTRY_IN_BLOCK);684 if (bit_pos < NR_DENTRY_IN_BLOCK)685 goto add_dentry;686 687 f2fs_put_page(dentry_page, 1);688 }689 690 /* Move to next level to find the empty slot for new dentry */691 ++level;692 goto start;693add_dentry:694 f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);695 696 if (inode) {697 f2fs_down_write(&F2FS_I(inode)->i_sem);698 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);699 if (IS_ERR(page)) {700 err = PTR_ERR(page);701 goto fail;702 }703 }704 705 make_dentry_ptr_block(NULL, &d, dentry_blk);706 f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,707 bit_pos);708 709 set_page_dirty(dentry_page);710 711 if (inode) {712 f2fs_i_pino_write(inode, dir->i_ino);713 714 /* synchronize inode page's data from inode cache */715 if (is_inode_flag_set(inode, FI_NEW_INODE))716 f2fs_update_inode(inode, page);717 718 f2fs_put_page(page, 1);719 }720 721 f2fs_update_parent_metadata(dir, inode, current_depth);722fail:723 if (inode)724 f2fs_up_write(&F2FS_I(inode)->i_sem);725 726 f2fs_put_page(dentry_page, 1);727 728 return err;729}730 731int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,732 struct inode *inode, nid_t ino, umode_t mode)733{734 int err = -EAGAIN;735 736 if (f2fs_has_inline_dentry(dir)) {737 /*738 * Should get i_xattr_sem to keep the lock order:739 * i_xattr_sem -> inode_page lock used by f2fs_setxattr.740 */741 f2fs_down_read(&F2FS_I(dir)->i_xattr_sem);742 err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);743 f2fs_up_read(&F2FS_I(dir)->i_xattr_sem);744 }745 if (err == -EAGAIN)746 err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);747 748 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);749 return err;750}751 752/*753 * Caller should grab and release a rwsem by calling f2fs_lock_op() and754 * f2fs_unlock_op().755 */756int f2fs_do_add_link(struct inode *dir, const struct qstr *name,757 struct inode *inode, nid_t ino, umode_t mode)758{759 struct f2fs_filename fname;760 struct page *page = NULL;761 struct f2fs_dir_entry *de = NULL;762 int err;763 764 err = f2fs_setup_filename(dir, name, 0, &fname);765 if (err)766 return err;767 768 /*769 * An immature stackable filesystem shows a race condition between lookup770 * and create. If we have same task when doing lookup and create, it's771 * definitely fine as expected by VFS normally. Otherwise, let's just772 * verify on-disk dentry one more time, which guarantees filesystem773 * consistency more.774 */775 if (current != F2FS_I(dir)->task) {776 de = __f2fs_find_entry(dir, &fname, &page);777 F2FS_I(dir)->task = NULL;778 }779 if (de) {780 f2fs_put_page(page, 0);781 err = -EEXIST;782 } else if (IS_ERR(page)) {783 err = PTR_ERR(page);784 } else {785 err = f2fs_add_dentry(dir, &fname, inode, ino, mode);786 }787 f2fs_free_filename(&fname);788 return err;789}790 791int f2fs_do_tmpfile(struct inode *inode, struct inode *dir,792 struct f2fs_filename *fname)793{794 struct page *page;795 int err = 0;796 797 f2fs_down_write(&F2FS_I(inode)->i_sem);798 page = f2fs_init_inode_metadata(inode, dir, fname, NULL);799 if (IS_ERR(page)) {800 err = PTR_ERR(page);801 goto fail;802 }803 f2fs_put_page(page, 1);804 805 clear_inode_flag(inode, FI_NEW_INODE);806 f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);807fail:808 f2fs_up_write(&F2FS_I(inode)->i_sem);809 return err;810}811 812void f2fs_drop_nlink(struct inode *dir, struct inode *inode)813{814 struct f2fs_sb_info *sbi = F2FS_I_SB(dir);815 816 f2fs_down_write(&F2FS_I(inode)->i_sem);817 818 if (S_ISDIR(inode->i_mode))819 f2fs_i_links_write(dir, false);820 inode_set_ctime_current(inode);821 822 f2fs_i_links_write(inode, false);823 if (S_ISDIR(inode->i_mode)) {824 f2fs_i_links_write(inode, false);825 f2fs_i_size_write(inode, 0);826 }827 f2fs_up_write(&F2FS_I(inode)->i_sem);828 829 if (inode->i_nlink == 0)830 f2fs_add_orphan_inode(inode);831 else832 f2fs_release_orphan_inode(sbi);833}834 835/*836 * It only removes the dentry from the dentry page, corresponding name837 * entry in name page does not need to be touched during deletion.838 */839void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,840 struct inode *dir, struct inode *inode)841{842 struct f2fs_dentry_block *dentry_blk;843 unsigned int bit_pos;844 int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));845 pgoff_t index = page_folio(page)->index;846 int i;847 848 f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);849 850 if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)851 f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);852 853 if (f2fs_has_inline_dentry(dir))854 return f2fs_delete_inline_entry(dentry, page, dir, inode);855 856 lock_page(page);857 f2fs_wait_on_page_writeback(page, DATA, true, true);858 859 dentry_blk = page_address(page);860 bit_pos = dentry - dentry_blk->dentry;861 for (i = 0; i < slots; i++)862 __clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);863 864 /* Let's check and deallocate this dentry page */865 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,866 NR_DENTRY_IN_BLOCK,867 0);868 set_page_dirty(page);869 870 if (bit_pos == NR_DENTRY_IN_BLOCK &&871 !f2fs_truncate_hole(dir, index, index + 1)) {872 f2fs_clear_page_cache_dirty_tag(page_folio(page));873 clear_page_dirty_for_io(page);874 ClearPageUptodate(page);875 clear_page_private_all(page);876 877 inode_dec_dirty_pages(dir);878 f2fs_remove_dirty_inode(dir);879 }880 f2fs_put_page(page, 1);881 882 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));883 f2fs_mark_inode_dirty_sync(dir, false);884 885 if (inode)886 f2fs_drop_nlink(dir, inode);887}888 889bool f2fs_empty_dir(struct inode *dir)890{891 unsigned long bidx = 0;892 struct page *dentry_page;893 unsigned int bit_pos;894 struct f2fs_dentry_block *dentry_blk;895 unsigned long nblock = dir_blocks(dir);896 897 if (f2fs_has_inline_dentry(dir))898 return f2fs_empty_inline_dir(dir);899 900 while (bidx < nblock) {901 pgoff_t next_pgofs;902 903 dentry_page = f2fs_find_data_page(dir, bidx, &next_pgofs);904 if (IS_ERR(dentry_page)) {905 if (PTR_ERR(dentry_page) == -ENOENT) {906 bidx = next_pgofs;907 continue;908 } else {909 return false;910 }911 }912 913 dentry_blk = page_address(dentry_page);914 if (bidx == 0)915 bit_pos = 2;916 else917 bit_pos = 0;918 bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,919 NR_DENTRY_IN_BLOCK,920 bit_pos);921 922 f2fs_put_page(dentry_page, 0);923 924 if (bit_pos < NR_DENTRY_IN_BLOCK)925 return false;926 927 bidx++;928 }929 return true;930}931 932int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,933 unsigned int start_pos, struct fscrypt_str *fstr)934{935 unsigned char d_type = DT_UNKNOWN;936 unsigned int bit_pos;937 struct f2fs_dir_entry *de = NULL;938 struct fscrypt_str de_name = FSTR_INIT(NULL, 0);939 struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);940 struct blk_plug plug;941 bool readdir_ra = sbi->readdir_ra;942 bool found_valid_dirent = false;943 int err = 0;944 945 bit_pos = ((unsigned long)ctx->pos % d->max);946 947 if (readdir_ra)948 blk_start_plug(&plug);949 950 while (bit_pos < d->max) {951 bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);952 if (bit_pos >= d->max)953 break;954 955 de = &d->dentry[bit_pos];956 if (de->name_len == 0) {957 if (found_valid_dirent || !bit_pos) {958 f2fs_warn_ratelimited(sbi,959 "invalid namelen(0), ino:%u, run fsck to fix.",960 le32_to_cpu(de->ino));961 set_sbi_flag(sbi, SBI_NEED_FSCK);962 }963 bit_pos++;964 ctx->pos = start_pos + bit_pos;965 continue;966 }967 968 d_type = fs_ftype_to_dtype(de->file_type);969 970 de_name.name = d->filename[bit_pos];971 de_name.len = le16_to_cpu(de->name_len);972 973 /* check memory boundary before moving forward */974 bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));975 if (unlikely(bit_pos > d->max ||976 le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {977 f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",978 __func__, le16_to_cpu(de->name_len));979 set_sbi_flag(sbi, SBI_NEED_FSCK);980 err = -EFSCORRUPTED;981 f2fs_handle_error(sbi, ERROR_CORRUPTED_DIRENT);982 goto out;983 }984 985 if (IS_ENCRYPTED(d->inode)) {986 int save_len = fstr->len;987 988 err = fscrypt_fname_disk_to_usr(d->inode,989 (u32)le32_to_cpu(de->hash_code),990 0, &de_name, fstr);991 if (err)992 goto out;993 994 de_name = *fstr;995 fstr->len = save_len;996 }997 998 if (!dir_emit(ctx, de_name.name, de_name.len,999 le32_to_cpu(de->ino), d_type)) {1000 err = 1;1001 goto out;1002 }1003 1004 if (readdir_ra)1005 f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));1006 1007 ctx->pos = start_pos + bit_pos;1008 found_valid_dirent = true;1009 }1010out:1011 if (readdir_ra)1012 blk_finish_plug(&plug);1013 return err;1014}1015 1016static int f2fs_readdir(struct file *file, struct dir_context *ctx)1017{1018 struct inode *inode = file_inode(file);1019 unsigned long npages = dir_blocks(inode);1020 struct f2fs_dentry_block *dentry_blk = NULL;1021 struct page *dentry_page = NULL;1022 struct file_ra_state *ra = &file->f_ra;1023 loff_t start_pos = ctx->pos;1024 unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);1025 struct f2fs_dentry_ptr d;1026 struct fscrypt_str fstr = FSTR_INIT(NULL, 0);1027 int err = 0;1028 1029 if (IS_ENCRYPTED(inode)) {1030 err = fscrypt_prepare_readdir(inode);1031 if (err)1032 goto out;1033 1034 err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);1035 if (err < 0)1036 goto out;1037 }1038 1039 if (f2fs_has_inline_dentry(inode)) {1040 err = f2fs_read_inline_dir(file, ctx, &fstr);1041 goto out_free;1042 }1043 1044 for (; n < npages; ctx->pos = n * NR_DENTRY_IN_BLOCK) {1045 pgoff_t next_pgofs;1046 1047 /* allow readdir() to be interrupted */1048 if (fatal_signal_pending(current)) {1049 err = -ERESTARTSYS;1050 goto out_free;1051 }1052 cond_resched();1053 1054 /* readahead for multi pages of dir */1055 if (npages - n > 1 && !ra_has_index(ra, n))1056 page_cache_sync_readahead(inode->i_mapping, ra, file, n,1057 min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));1058 1059 dentry_page = f2fs_find_data_page(inode, n, &next_pgofs);1060 if (IS_ERR(dentry_page)) {1061 err = PTR_ERR(dentry_page);1062 if (err == -ENOENT) {1063 err = 0;1064 n = next_pgofs;1065 continue;1066 } else {1067 goto out_free;1068 }1069 }1070 1071 dentry_blk = page_address(dentry_page);1072 1073 make_dentry_ptr_block(inode, &d, dentry_blk);1074 1075 err = f2fs_fill_dentries(ctx, &d,1076 n * NR_DENTRY_IN_BLOCK, &fstr);1077 if (err) {1078 f2fs_put_page(dentry_page, 0);1079 break;1080 }1081 1082 f2fs_put_page(dentry_page, 0);1083 1084 n++;1085 }1086out_free:1087 fscrypt_fname_free_buffer(&fstr);1088out:1089 trace_f2fs_readdir(inode, start_pos, ctx->pos, err);1090 return err < 0 ? err : 0;1091}1092 1093const struct file_operations f2fs_dir_operations = {1094 .llseek = generic_file_llseek,1095 .read = generic_read_dir,1096 .iterate_shared = f2fs_readdir,1097 .fsync = f2fs_sync_file,1098 .unlocked_ioctl = f2fs_ioctl,1099#ifdef CONFIG_COMPAT1100 .compat_ioctl = f2fs_compat_ioctl,1101#endif1102};1103