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1// SPDX-License-Identifier: GPL-2.02/*3 * linux/fs/ext4/namei.c4 *5 * Copyright (C) 1992, 1993, 1994, 19956 * Remy Card (card@masi.ibp.fr)7 * Laboratoire MASI - Institut Blaise Pascal8 * Universite Pierre et Marie Curie (Paris VI)9 *10 * from11 *12 * linux/fs/minix/namei.c13 *14 * Copyright (C) 1991, 1992 Linus Torvalds15 *16 * Big-endian to little-endian byte-swapping/bitmaps by17 * David S. Miller (davem@caip.rutgers.edu), 199518 * Directory entry file type support and forward compatibility hooks19 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 199820 * Hash Tree Directory indexing (c)21 * Daniel Phillips, 200122 * Hash Tree Directory indexing porting23 * Christopher Li, 200224 * Hash Tree Directory indexing cleanup25 * Theodore Ts'o, 200226 */27 28#include <linux/fs.h>29#include <linux/pagemap.h>30#include <linux/time.h>31#include <linux/fcntl.h>32#include <linux/stat.h>33#include <linux/string.h>34#include <linux/quotaops.h>35#include <linux/buffer_head.h>36#include <linux/bio.h>37#include <linux/iversion.h>38#include <linux/unicode.h>39#include "ext4.h"40#include "ext4_jbd2.h"41 42#include "xattr.h"43#include "acl.h"44 45#include <trace/events/ext4.h>46/*47 * define how far ahead to read directories while searching them.48 */49#define NAMEI_RA_CHUNKS 250#define NAMEI_RA_BLOCKS 451#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)52 53static struct buffer_head *ext4_append(handle_t *handle,54 struct inode *inode,55 ext4_lblk_t *block)56{57 struct ext4_map_blocks map;58 struct buffer_head *bh;59 int err;60 61 if (unlikely(EXT4_SB(inode->i_sb)->s_max_dir_size_kb &&62 ((inode->i_size >> 10) >=63 EXT4_SB(inode->i_sb)->s_max_dir_size_kb)))64 return ERR_PTR(-ENOSPC);65 66 *block = inode->i_size >> inode->i_sb->s_blocksize_bits;67 map.m_lblk = *block;68 map.m_len = 1;69 70 /*71 * We're appending new directory block. Make sure the block is not72 * allocated yet, otherwise we will end up corrupting the73 * directory.74 */75 err = ext4_map_blocks(NULL, inode, &map, 0);76 if (err < 0)77 return ERR_PTR(err);78 if (err) {79 EXT4_ERROR_INODE(inode, "Logical block already allocated");80 return ERR_PTR(-EFSCORRUPTED);81 }82 83 bh = ext4_bread(handle, inode, *block, EXT4_GET_BLOCKS_CREATE);84 if (IS_ERR(bh))85 return bh;86 inode->i_size += inode->i_sb->s_blocksize;87 EXT4_I(inode)->i_disksize = inode->i_size;88 err = ext4_mark_inode_dirty(handle, inode);89 if (err)90 goto out;91 BUFFER_TRACE(bh, "get_write_access");92 err = ext4_journal_get_write_access(handle, inode->i_sb, bh,93 EXT4_JTR_NONE);94 if (err)95 goto out;96 return bh;97 98out:99 brelse(bh);100 ext4_std_error(inode->i_sb, err);101 return ERR_PTR(err);102}103 104static int ext4_dx_csum_verify(struct inode *inode,105 struct ext4_dir_entry *dirent);106 107/*108 * Hints to ext4_read_dirblock regarding whether we expect a directory109 * block being read to be an index block, or a block containing110 * directory entries (and if the latter, whether it was found via a111 * logical block in an htree index block). This is used to control112 * what sort of sanity checkinig ext4_read_dirblock() will do on the113 * directory block read from the storage device. EITHER will means114 * the caller doesn't know what kind of directory block will be read,115 * so no specific verification will be done.116 */117typedef enum {118 EITHER, INDEX, DIRENT, DIRENT_HTREE119} dirblock_type_t;120 121#define ext4_read_dirblock(inode, block, type) \122 __ext4_read_dirblock((inode), (block), (type), __func__, __LINE__)123 124static struct buffer_head *__ext4_read_dirblock(struct inode *inode,125 ext4_lblk_t block,126 dirblock_type_t type,127 const char *func,128 unsigned int line)129{130 struct buffer_head *bh;131 struct ext4_dir_entry *dirent;132 int is_dx_block = 0;133 134 if (block >= inode->i_size >> inode->i_blkbits) {135 ext4_error_inode(inode, func, line, block,136 "Attempting to read directory block (%u) that is past i_size (%llu)",137 block, inode->i_size);138 return ERR_PTR(-EFSCORRUPTED);139 }140 141 if (ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_EIO))142 bh = ERR_PTR(-EIO);143 else144 bh = ext4_bread(NULL, inode, block, 0);145 if (IS_ERR(bh)) {146 __ext4_warning(inode->i_sb, func, line,147 "inode #%lu: lblock %lu: comm %s: "148 "error %ld reading directory block",149 inode->i_ino, (unsigned long)block,150 current->comm, PTR_ERR(bh));151 152 return bh;153 }154 /* The first directory block must not be a hole. */155 if (!bh && (type == INDEX || type == DIRENT_HTREE || block == 0)) {156 ext4_error_inode(inode, func, line, block,157 "Directory hole found for htree %s block %u",158 (type == INDEX) ? "index" : "leaf", block);159 return ERR_PTR(-EFSCORRUPTED);160 }161 if (!bh)162 return NULL;163 dirent = (struct ext4_dir_entry *) bh->b_data;164 /* Determine whether or not we have an index block */165 if (is_dx(inode)) {166 if (block == 0)167 is_dx_block = 1;168 else if (ext4_rec_len_from_disk(dirent->rec_len,169 inode->i_sb->s_blocksize) ==170 inode->i_sb->s_blocksize)171 is_dx_block = 1;172 }173 if (!is_dx_block && type == INDEX) {174 ext4_error_inode(inode, func, line, block,175 "directory leaf block found instead of index block");176 brelse(bh);177 return ERR_PTR(-EFSCORRUPTED);178 }179 if (!ext4_has_metadata_csum(inode->i_sb) ||180 buffer_verified(bh))181 return bh;182 183 /*184 * An empty leaf block can get mistaken for a index block; for185 * this reason, we can only check the index checksum when the186 * caller is sure it should be an index block.187 */188 if (is_dx_block && type == INDEX) {189 if (ext4_dx_csum_verify(inode, dirent) &&190 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))191 set_buffer_verified(bh);192 else {193 ext4_error_inode_err(inode, func, line, block,194 EFSBADCRC,195 "Directory index failed checksum");196 brelse(bh);197 return ERR_PTR(-EFSBADCRC);198 }199 }200 if (!is_dx_block) {201 if (ext4_dirblock_csum_verify(inode, bh) &&202 !ext4_simulate_fail(inode->i_sb, EXT4_SIM_DIRBLOCK_CRC))203 set_buffer_verified(bh);204 else {205 ext4_error_inode_err(inode, func, line, block,206 EFSBADCRC,207 "Directory block failed checksum");208 brelse(bh);209 return ERR_PTR(-EFSBADCRC);210 }211 }212 return bh;213}214 215#ifdef DX_DEBUG216#define dxtrace(command) command217#else218#define dxtrace(command)219#endif220 221struct fake_dirent222{223 __le32 inode;224 __le16 rec_len;225 u8 name_len;226 u8 file_type;227};228 229struct dx_countlimit230{231 __le16 limit;232 __le16 count;233};234 235struct dx_entry236{237 __le32 hash;238 __le32 block;239};240 241/*242 * dx_root_info is laid out so that if it should somehow get overlaid by a243 * dirent the two low bits of the hash version will be zero. Therefore, the244 * hash version mod 4 should never be 0. Sincerely, the paranoia department.245 */246 247struct dx_root248{249 struct fake_dirent dot;250 char dot_name[4];251 struct fake_dirent dotdot;252 char dotdot_name[4];253 struct dx_root_info254 {255 __le32 reserved_zero;256 u8 hash_version;257 u8 info_length; /* 8 */258 u8 indirect_levels;259 u8 unused_flags;260 }261 info;262 struct dx_entry entries[];263};264 265struct dx_node266{267 struct fake_dirent fake;268 struct dx_entry entries[];269};270 271 272struct dx_frame273{274 struct buffer_head *bh;275 struct dx_entry *entries;276 struct dx_entry *at;277};278 279struct dx_map_entry280{281 u32 hash;282 u16 offs;283 u16 size;284};285 286/*287 * This goes at the end of each htree block.288 */289struct dx_tail {290 u32 dt_reserved;291 __le32 dt_checksum; /* crc32c(uuid+inum+dirblock) */292};293 294static inline ext4_lblk_t dx_get_block(struct dx_entry *entry);295static void dx_set_block(struct dx_entry *entry, ext4_lblk_t value);296static inline unsigned dx_get_hash(struct dx_entry *entry);297static void dx_set_hash(struct dx_entry *entry, unsigned value);298static unsigned dx_get_count(struct dx_entry *entries);299static unsigned dx_get_limit(struct dx_entry *entries);300static void dx_set_count(struct dx_entry *entries, unsigned value);301static void dx_set_limit(struct dx_entry *entries, unsigned value);302static unsigned dx_root_limit(struct inode *dir, unsigned infosize);303static unsigned dx_node_limit(struct inode *dir);304static struct dx_frame *dx_probe(struct ext4_filename *fname,305 struct inode *dir,306 struct dx_hash_info *hinfo,307 struct dx_frame *frame);308static void dx_release(struct dx_frame *frames);309static int dx_make_map(struct inode *dir, struct buffer_head *bh,310 struct dx_hash_info *hinfo,311 struct dx_map_entry *map_tail);312static void dx_sort_map(struct dx_map_entry *map, unsigned count);313static struct ext4_dir_entry_2 *dx_move_dirents(struct inode *dir, char *from,314 char *to, struct dx_map_entry *offsets,315 int count, unsigned int blocksize);316static struct ext4_dir_entry_2 *dx_pack_dirents(struct inode *dir, char *base,317 unsigned int blocksize);318static void dx_insert_block(struct dx_frame *frame,319 u32 hash, ext4_lblk_t block);320static int ext4_htree_next_block(struct inode *dir, __u32 hash,321 struct dx_frame *frame,322 struct dx_frame *frames,323 __u32 *start_hash);324static struct buffer_head * ext4_dx_find_entry(struct inode *dir,325 struct ext4_filename *fname,326 struct ext4_dir_entry_2 **res_dir);327static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,328 struct inode *dir, struct inode *inode);329 330/* checksumming functions */331void ext4_initialize_dirent_tail(struct buffer_head *bh,332 unsigned int blocksize)333{334 struct ext4_dir_entry_tail *t = EXT4_DIRENT_TAIL(bh->b_data, blocksize);335 336 memset(t, 0, sizeof(struct ext4_dir_entry_tail));337 t->det_rec_len = ext4_rec_len_to_disk(338 sizeof(struct ext4_dir_entry_tail), blocksize);339 t->det_reserved_ft = EXT4_FT_DIR_CSUM;340}341 342/* Walk through a dirent block to find a checksum "dirent" at the tail */343static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,344 struct buffer_head *bh)345{346 struct ext4_dir_entry_tail *t;347 int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);348 349#ifdef PARANOID350 struct ext4_dir_entry *d, *top;351 352 d = (struct ext4_dir_entry *)bh->b_data;353 top = (struct ext4_dir_entry *)(bh->b_data +354 (blocksize - sizeof(struct ext4_dir_entry_tail)));355 while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))356 d = (struct ext4_dir_entry *)(((void *)d) +357 ext4_rec_len_from_disk(d->rec_len, blocksize));358 359 if (d != top)360 return NULL;361 362 t = (struct ext4_dir_entry_tail *)d;363#else364 t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));365#endif366 367 if (t->det_reserved_zero1 ||368 (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=369 sizeof(struct ext4_dir_entry_tail)) ||370 t->det_reserved_zero2 ||371 t->det_reserved_ft != EXT4_FT_DIR_CSUM)372 return NULL;373 374 return t;375}376 377static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)378{379 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);380 struct ext4_inode_info *ei = EXT4_I(inode);381 __u32 csum;382 383 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);384 return cpu_to_le32(csum);385}386 387#define warn_no_space_for_csum(inode) \388 __warn_no_space_for_csum((inode), __func__, __LINE__)389 390static void __warn_no_space_for_csum(struct inode *inode, const char *func,391 unsigned int line)392{393 __ext4_warning_inode(inode, func, line,394 "No space for directory leaf checksum. Please run e2fsck -D.");395}396 397int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)398{399 struct ext4_dir_entry_tail *t;400 401 if (!ext4_has_metadata_csum(inode->i_sb))402 return 1;403 404 t = get_dirent_tail(inode, bh);405 if (!t) {406 warn_no_space_for_csum(inode);407 return 0;408 }409 410 if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,411 (char *)t - bh->b_data))412 return 0;413 414 return 1;415}416 417static void ext4_dirblock_csum_set(struct inode *inode,418 struct buffer_head *bh)419{420 struct ext4_dir_entry_tail *t;421 422 if (!ext4_has_metadata_csum(inode->i_sb))423 return;424 425 t = get_dirent_tail(inode, bh);426 if (!t) {427 warn_no_space_for_csum(inode);428 return;429 }430 431 t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,432 (char *)t - bh->b_data);433}434 435int ext4_handle_dirty_dirblock(handle_t *handle,436 struct inode *inode,437 struct buffer_head *bh)438{439 ext4_dirblock_csum_set(inode, bh);440 return ext4_handle_dirty_metadata(handle, inode, bh);441}442 443static struct dx_countlimit *get_dx_countlimit(struct inode *inode,444 struct ext4_dir_entry *dirent,445 int *offset)446{447 struct ext4_dir_entry *dp;448 struct dx_root_info *root;449 int count_offset;450 int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);451 unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);452 453 if (rlen == blocksize)454 count_offset = 8;455 else if (rlen == 12) {456 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);457 if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)458 return NULL;459 root = (struct dx_root_info *)(((void *)dp + 12));460 if (root->reserved_zero ||461 root->info_length != sizeof(struct dx_root_info))462 return NULL;463 count_offset = 32;464 } else465 return NULL;466 467 if (offset)468 *offset = count_offset;469 return (struct dx_countlimit *)(((void *)dirent) + count_offset);470}471 472static __le32 ext4_dx_csum(struct inode *inode, struct ext4_dir_entry *dirent,473 int count_offset, int count, struct dx_tail *t)474{475 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);476 struct ext4_inode_info *ei = EXT4_I(inode);477 __u32 csum;478 int size;479 __u32 dummy_csum = 0;480 int offset = offsetof(struct dx_tail, dt_checksum);481 482 size = count_offset + (count * sizeof(struct dx_entry));483 csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)dirent, size);484 csum = ext4_chksum(sbi, csum, (__u8 *)t, offset);485 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));486 487 return cpu_to_le32(csum);488}489 490static int ext4_dx_csum_verify(struct inode *inode,491 struct ext4_dir_entry *dirent)492{493 struct dx_countlimit *c;494 struct dx_tail *t;495 int count_offset, limit, count;496 497 if (!ext4_has_metadata_csum(inode->i_sb))498 return 1;499 500 c = get_dx_countlimit(inode, dirent, &count_offset);501 if (!c) {502 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");503 return 0;504 }505 limit = le16_to_cpu(c->limit);506 count = le16_to_cpu(c->count);507 if (count_offset + (limit * sizeof(struct dx_entry)) >508 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {509 warn_no_space_for_csum(inode);510 return 0;511 }512 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);513 514 if (t->dt_checksum != ext4_dx_csum(inode, dirent, count_offset,515 count, t))516 return 0;517 return 1;518}519 520static void ext4_dx_csum_set(struct inode *inode, struct ext4_dir_entry *dirent)521{522 struct dx_countlimit *c;523 struct dx_tail *t;524 int count_offset, limit, count;525 526 if (!ext4_has_metadata_csum(inode->i_sb))527 return;528 529 c = get_dx_countlimit(inode, dirent, &count_offset);530 if (!c) {531 EXT4_ERROR_INODE(inode, "dir seems corrupt? Run e2fsck -D.");532 return;533 }534 limit = le16_to_cpu(c->limit);535 count = le16_to_cpu(c->count);536 if (count_offset + (limit * sizeof(struct dx_entry)) >537 EXT4_BLOCK_SIZE(inode->i_sb) - sizeof(struct dx_tail)) {538 warn_no_space_for_csum(inode);539 return;540 }541 t = (struct dx_tail *)(((struct dx_entry *)c) + limit);542 543 t->dt_checksum = ext4_dx_csum(inode, dirent, count_offset, count, t);544}545 546static inline int ext4_handle_dirty_dx_node(handle_t *handle,547 struct inode *inode,548 struct buffer_head *bh)549{550 ext4_dx_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);551 return ext4_handle_dirty_metadata(handle, inode, bh);552}553 554/*555 * p is at least 6 bytes before the end of page556 */557static inline struct ext4_dir_entry_2 *558ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)559{560 return (struct ext4_dir_entry_2 *)((char *)p +561 ext4_rec_len_from_disk(p->rec_len, blocksize));562}563 564/*565 * Future: use high four bits of block for coalesce-on-delete flags566 * Mask them off for now.567 */568 569static inline ext4_lblk_t dx_get_block(struct dx_entry *entry)570{571 return le32_to_cpu(entry->block) & 0x0fffffff;572}573 574static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t value)575{576 entry->block = cpu_to_le32(value);577}578 579static inline unsigned dx_get_hash(struct dx_entry *entry)580{581 return le32_to_cpu(entry->hash);582}583 584static inline void dx_set_hash(struct dx_entry *entry, unsigned value)585{586 entry->hash = cpu_to_le32(value);587}588 589static inline unsigned dx_get_count(struct dx_entry *entries)590{591 return le16_to_cpu(((struct dx_countlimit *) entries)->count);592}593 594static inline unsigned dx_get_limit(struct dx_entry *entries)595{596 return le16_to_cpu(((struct dx_countlimit *) entries)->limit);597}598 599static inline void dx_set_count(struct dx_entry *entries, unsigned value)600{601 ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);602}603 604static inline void dx_set_limit(struct dx_entry *entries, unsigned value)605{606 ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);607}608 609static inline unsigned dx_root_limit(struct inode *dir, unsigned infosize)610{611 unsigned int entry_space = dir->i_sb->s_blocksize -612 ext4_dir_rec_len(1, NULL) -613 ext4_dir_rec_len(2, NULL) - infosize;614 615 if (ext4_has_metadata_csum(dir->i_sb))616 entry_space -= sizeof(struct dx_tail);617 return entry_space / sizeof(struct dx_entry);618}619 620static inline unsigned dx_node_limit(struct inode *dir)621{622 unsigned int entry_space = dir->i_sb->s_blocksize -623 ext4_dir_rec_len(0, dir);624 625 if (ext4_has_metadata_csum(dir->i_sb))626 entry_space -= sizeof(struct dx_tail);627 return entry_space / sizeof(struct dx_entry);628}629 630/*631 * Debug632 */633#ifdef DX_DEBUG634static void dx_show_index(char * label, struct dx_entry *entries)635{636 int i, n = dx_get_count (entries);637 printk(KERN_DEBUG "%s index", label);638 for (i = 0; i < n; i++) {639 printk(KERN_CONT " %x->%lu",640 i ? dx_get_hash(entries + i) : 0,641 (unsigned long)dx_get_block(entries + i));642 }643 printk(KERN_CONT "\n");644}645 646struct stats647{648 unsigned names;649 unsigned space;650 unsigned bcount;651};652 653static struct stats dx_show_leaf(struct inode *dir,654 struct dx_hash_info *hinfo,655 struct ext4_dir_entry_2 *de,656 int size, int show_names)657{658 unsigned names = 0, space = 0;659 char *base = (char *) de;660 struct dx_hash_info h = *hinfo;661 662 printk("names: ");663 while ((char *) de < base + size)664 {665 if (de->inode)666 {667 if (show_names)668 {669#ifdef CONFIG_FS_ENCRYPTION670 int len;671 char *name;672 struct fscrypt_str fname_crypto_str =673 FSTR_INIT(NULL, 0);674 int res = 0;675 676 name = de->name;677 len = de->name_len;678 if (!IS_ENCRYPTED(dir)) {679 /* Directory is not encrypted */680 (void) ext4fs_dirhash(dir, de->name,681 de->name_len, &h);682 printk("%*.s:(U)%x.%u ", len,683 name, h.hash,684 (unsigned) ((char *) de685 - base));686 } else {687 struct fscrypt_str de_name =688 FSTR_INIT(name, len);689 690 /* Directory is encrypted */691 res = fscrypt_fname_alloc_buffer(692 len, &fname_crypto_str);693 if (res)694 printk(KERN_WARNING "Error "695 "allocating crypto "696 "buffer--skipping "697 "crypto\n");698 res = fscrypt_fname_disk_to_usr(dir,699 0, 0, &de_name,700 &fname_crypto_str);701 if (res) {702 printk(KERN_WARNING "Error "703 "converting filename "704 "from disk to usr"705 "\n");706 name = "??";707 len = 2;708 } else {709 name = fname_crypto_str.name;710 len = fname_crypto_str.len;711 }712 if (IS_CASEFOLDED(dir))713 h.hash = EXT4_DIRENT_HASH(de);714 else715 (void) ext4fs_dirhash(dir,716 de->name,717 de->name_len, &h);718 printk("%*.s:(E)%x.%u ", len, name,719 h.hash, (unsigned) ((char *) de720 - base));721 fscrypt_fname_free_buffer(722 &fname_crypto_str);723 }724#else725 int len = de->name_len;726 char *name = de->name;727 (void) ext4fs_dirhash(dir, de->name,728 de->name_len, &h);729 printk("%*.s:%x.%u ", len, name, h.hash,730 (unsigned) ((char *) de - base));731#endif732 }733 space += ext4_dir_rec_len(de->name_len, dir);734 names++;735 }736 de = ext4_next_entry(de, size);737 }738 printk(KERN_CONT "(%i)\n", names);739 return (struct stats) { names, space, 1 };740}741 742struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,743 struct dx_entry *entries, int levels)744{745 unsigned blocksize = dir->i_sb->s_blocksize;746 unsigned count = dx_get_count(entries), names = 0, space = 0, i;747 unsigned bcount = 0;748 struct buffer_head *bh;749 printk("%i indexed blocks...\n", count);750 for (i = 0; i < count; i++, entries++)751 {752 ext4_lblk_t block = dx_get_block(entries);753 ext4_lblk_t hash = i ? dx_get_hash(entries): 0;754 u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;755 struct stats stats;756 printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);757 bh = ext4_bread(NULL,dir, block, 0);758 if (!bh || IS_ERR(bh))759 continue;760 stats = levels?761 dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):762 dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *)763 bh->b_data, blocksize, 0);764 names += stats.names;765 space += stats.space;766 bcount += stats.bcount;767 brelse(bh);768 }769 if (bcount)770 printk(KERN_DEBUG "%snames %u, fullness %u (%u%%)\n",771 levels ? "" : " ", names, space/bcount,772 (space/bcount)*100/blocksize);773 return (struct stats) { names, space, bcount};774}775 776/*777 * Linear search cross check778 */779static inline void htree_rep_invariant_check(struct dx_entry *at,780 struct dx_entry *target,781 u32 hash, unsigned int n)782{783 while (n--) {784 dxtrace(printk(KERN_CONT ","));785 if (dx_get_hash(++at) > hash) {786 at--;787 break;788 }789 }790 ASSERT(at == target - 1);791}792#else /* DX_DEBUG */793static inline void htree_rep_invariant_check(struct dx_entry *at,794 struct dx_entry *target,795 u32 hash, unsigned int n)796{797}798#endif /* DX_DEBUG */799 800/*801 * Probe for a directory leaf block to search.802 *803 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format804 * error in the directory index, and the caller should fall back to805 * searching the directory normally. The callers of dx_probe **MUST**806 * check for this error code, and make sure it never gets reflected807 * back to userspace.808 */809static struct dx_frame *810dx_probe(struct ext4_filename *fname, struct inode *dir,811 struct dx_hash_info *hinfo, struct dx_frame *frame_in)812{813 unsigned count, indirect, level, i;814 struct dx_entry *at, *entries, *p, *q, *m;815 struct dx_root *root;816 struct dx_frame *frame = frame_in;817 struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);818 u32 hash;819 ext4_lblk_t block;820 ext4_lblk_t blocks[EXT4_HTREE_LEVEL];821 822 memset(frame_in, 0, EXT4_HTREE_LEVEL * sizeof(frame_in[0]));823 frame->bh = ext4_read_dirblock(dir, 0, INDEX);824 if (IS_ERR(frame->bh))825 return (struct dx_frame *) frame->bh;826 827 root = (struct dx_root *) frame->bh->b_data;828 if (root->info.hash_version != DX_HASH_TEA &&829 root->info.hash_version != DX_HASH_HALF_MD4 &&830 root->info.hash_version != DX_HASH_LEGACY &&831 root->info.hash_version != DX_HASH_SIPHASH) {832 ext4_warning_inode(dir, "Unrecognised inode hash code %u",833 root->info.hash_version);834 goto fail;835 }836 if (ext4_hash_in_dirent(dir)) {837 if (root->info.hash_version != DX_HASH_SIPHASH) {838 ext4_warning_inode(dir,839 "Hash in dirent, but hash is not SIPHASH");840 goto fail;841 }842 } else {843 if (root->info.hash_version == DX_HASH_SIPHASH) {844 ext4_warning_inode(dir,845 "Hash code is SIPHASH, but hash not in dirent");846 goto fail;847 }848 }849 if (fname)850 hinfo = &fname->hinfo;851 hinfo->hash_version = root->info.hash_version;852 if (hinfo->hash_version <= DX_HASH_TEA)853 hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;854 hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;855 /* hash is already computed for encrypted casefolded directory */856 if (fname && fname_name(fname) &&857 !(IS_ENCRYPTED(dir) && IS_CASEFOLDED(dir))) {858 int ret = ext4fs_dirhash(dir, fname_name(fname),859 fname_len(fname), hinfo);860 if (ret < 0) {861 ret_err = ERR_PTR(ret);862 goto fail;863 }864 }865 hash = hinfo->hash;866 867 if (root->info.unused_flags & 1) {868 ext4_warning_inode(dir, "Unimplemented hash flags: %#06x",869 root->info.unused_flags);870 goto fail;871 }872 873 indirect = root->info.indirect_levels;874 if (indirect >= ext4_dir_htree_level(dir->i_sb)) {875 ext4_warning(dir->i_sb,876 "Directory (ino: %lu) htree depth %#06x exceed"877 "supported value", dir->i_ino,878 ext4_dir_htree_level(dir->i_sb));879 if (ext4_dir_htree_level(dir->i_sb) < EXT4_HTREE_LEVEL) {880 ext4_warning(dir->i_sb, "Enable large directory "881 "feature to access it");882 }883 goto fail;884 }885 886 entries = (struct dx_entry *)(((char *)&root->info) +887 root->info.info_length);888 889 if (dx_get_limit(entries) != dx_root_limit(dir,890 root->info.info_length)) {891 ext4_warning_inode(dir, "dx entry: limit %u != root limit %u",892 dx_get_limit(entries),893 dx_root_limit(dir, root->info.info_length));894 goto fail;895 }896 897 dxtrace(printk("Look up %x", hash));898 level = 0;899 blocks[0] = 0;900 while (1) {901 count = dx_get_count(entries);902 if (!count || count > dx_get_limit(entries)) {903 ext4_warning_inode(dir,904 "dx entry: count %u beyond limit %u",905 count, dx_get_limit(entries));906 goto fail;907 }908 909 p = entries + 1;910 q = entries + count - 1;911 while (p <= q) {912 m = p + (q - p) / 2;913 dxtrace(printk(KERN_CONT "."));914 if (dx_get_hash(m) > hash)915 q = m - 1;916 else917 p = m + 1;918 }919 920 htree_rep_invariant_check(entries, p, hash, count - 1);921 922 at = p - 1;923 dxtrace(printk(KERN_CONT " %x->%u\n",924 at == entries ? 0 : dx_get_hash(at),925 dx_get_block(at)));926 frame->entries = entries;927 frame->at = at;928 929 block = dx_get_block(at);930 for (i = 0; i <= level; i++) {931 if (blocks[i] == block) {932 ext4_warning_inode(dir,933 "dx entry: tree cycle block %u points back to block %u",934 blocks[level], block);935 goto fail;936 }937 }938 if (++level > indirect)939 return frame;940 blocks[level] = block;941 frame++;942 frame->bh = ext4_read_dirblock(dir, block, INDEX);943 if (IS_ERR(frame->bh)) {944 ret_err = (struct dx_frame *) frame->bh;945 frame->bh = NULL;946 goto fail;947 }948 949 entries = ((struct dx_node *) frame->bh->b_data)->entries;950 951 if (dx_get_limit(entries) != dx_node_limit(dir)) {952 ext4_warning_inode(dir,953 "dx entry: limit %u != node limit %u",954 dx_get_limit(entries), dx_node_limit(dir));955 goto fail;956 }957 }958fail:959 while (frame >= frame_in) {960 brelse(frame->bh);961 frame--;962 }963 964 if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))965 ext4_warning_inode(dir,966 "Corrupt directory, running e2fsck is recommended");967 return ret_err;968}969 970static void dx_release(struct dx_frame *frames)971{972 struct dx_root_info *info;973 int i;974 unsigned int indirect_levels;975 976 if (frames[0].bh == NULL)977 return;978 979 info = &((struct dx_root *)frames[0].bh->b_data)->info;980 /* save local copy, "info" may be freed after brelse() */981 indirect_levels = info->indirect_levels;982 for (i = 0; i <= indirect_levels; i++) {983 if (frames[i].bh == NULL)984 break;985 brelse(frames[i].bh);986 frames[i].bh = NULL;987 }988}989 990/*991 * This function increments the frame pointer to search the next leaf992 * block, and reads in the necessary intervening nodes if the search993 * should be necessary. Whether or not the search is necessary is994 * controlled by the hash parameter. If the hash value is even, then995 * the search is only continued if the next block starts with that996 * hash value. This is used if we are searching for a specific file.997 *998 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.999 *1000 * This function returns 1 if the caller should continue to search,1001 * or 0 if it should not. If there is an error reading one of the1002 * index blocks, it will a negative error code.1003 *1004 * If start_hash is non-null, it will be filled in with the starting1005 * hash of the next page.1006 */1007static int ext4_htree_next_block(struct inode *dir, __u32 hash,1008 struct dx_frame *frame,1009 struct dx_frame *frames,1010 __u32 *start_hash)1011{1012 struct dx_frame *p;1013 struct buffer_head *bh;1014 int num_frames = 0;1015 __u32 bhash;1016 1017 p = frame;1018 /*1019 * Find the next leaf page by incrementing the frame pointer.1020 * If we run out of entries in the interior node, loop around and1021 * increment pointer in the parent node. When we break out of1022 * this loop, num_frames indicates the number of interior1023 * nodes need to be read.1024 */1025 while (1) {1026 if (++(p->at) < p->entries + dx_get_count(p->entries))1027 break;1028 if (p == frames)1029 return 0;1030 num_frames++;1031 p--;1032 }1033 1034 /*1035 * If the hash is 1, then continue only if the next page has a1036 * continuation hash of any value. This is used for readdir1037 * handling. Otherwise, check to see if the hash matches the1038 * desired continuation hash. If it doesn't, return since1039 * there's no point to read in the successive index pages.1040 */1041 bhash = dx_get_hash(p->at);1042 if (start_hash)1043 *start_hash = bhash;1044 if ((hash & 1) == 0) {1045 if ((bhash & ~1) != hash)1046 return 0;1047 }1048 /*1049 * If the hash is HASH_NB_ALWAYS, we always go to the next1050 * block so no check is necessary1051 */1052 while (num_frames--) {1053 bh = ext4_read_dirblock(dir, dx_get_block(p->at), INDEX);1054 if (IS_ERR(bh))1055 return PTR_ERR(bh);1056 p++;1057 brelse(p->bh);1058 p->bh = bh;1059 p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;1060 }1061 return 1;1062}1063 1064 1065/*1066 * This function fills a red-black tree with information from a1067 * directory block. It returns the number directory entries loaded1068 * into the tree. If there is an error it is returned in err.1069 */1070static int htree_dirblock_to_tree(struct file *dir_file,1071 struct inode *dir, ext4_lblk_t block,1072 struct dx_hash_info *hinfo,1073 __u32 start_hash, __u32 start_minor_hash)1074{1075 struct buffer_head *bh;1076 struct ext4_dir_entry_2 *de, *top;1077 int err = 0, count = 0;1078 struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;1079 int csum = ext4_has_metadata_csum(dir->i_sb);1080 1081 dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",1082 (unsigned long)block));1083 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);1084 if (IS_ERR(bh))1085 return PTR_ERR(bh);1086 1087 de = (struct ext4_dir_entry_2 *) bh->b_data;1088 /* csum entries are not larger in the casefolded encrypted case */1089 top = (struct ext4_dir_entry_2 *) ((char *) de +1090 dir->i_sb->s_blocksize -1091 ext4_dir_rec_len(0,1092 csum ? NULL : dir));1093 /* Check if the directory is encrypted */1094 if (IS_ENCRYPTED(dir)) {1095 err = fscrypt_prepare_readdir(dir);1096 if (err < 0) {1097 brelse(bh);1098 return err;1099 }1100 err = fscrypt_fname_alloc_buffer(EXT4_NAME_LEN,1101 &fname_crypto_str);1102 if (err < 0) {1103 brelse(bh);1104 return err;1105 }1106 }1107 1108 for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {1109 if (ext4_check_dir_entry(dir, NULL, de, bh,1110 bh->b_data, bh->b_size,1111 (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))1112 + ((char *)de - bh->b_data))) {1113 /* silently ignore the rest of the block */1114 break;1115 }1116 if (ext4_hash_in_dirent(dir)) {1117 if (de->name_len && de->inode) {1118 hinfo->hash = EXT4_DIRENT_HASH(de);1119 hinfo->minor_hash = EXT4_DIRENT_MINOR_HASH(de);1120 } else {1121 hinfo->hash = 0;1122 hinfo->minor_hash = 0;1123 }1124 } else {1125 err = ext4fs_dirhash(dir, de->name,1126 de->name_len, hinfo);1127 if (err < 0) {1128 count = err;1129 goto errout;1130 }1131 }1132 if ((hinfo->hash < start_hash) ||1133 ((hinfo->hash == start_hash) &&1134 (hinfo->minor_hash < start_minor_hash)))1135 continue;1136 if (de->inode == 0)1137 continue;1138 if (!IS_ENCRYPTED(dir)) {1139 tmp_str.name = de->name;1140 tmp_str.len = de->name_len;1141 err = ext4_htree_store_dirent(dir_file,1142 hinfo->hash, hinfo->minor_hash, de,1143 &tmp_str);1144 } else {1145 int save_len = fname_crypto_str.len;1146 struct fscrypt_str de_name = FSTR_INIT(de->name,1147 de->name_len);1148 1149 /* Directory is encrypted */1150 err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,1151 hinfo->minor_hash, &de_name,1152 &fname_crypto_str);1153 if (err) {1154 count = err;1155 goto errout;1156 }1157 err = ext4_htree_store_dirent(dir_file,1158 hinfo->hash, hinfo->minor_hash, de,1159 &fname_crypto_str);1160 fname_crypto_str.len = save_len;1161 }1162 if (err != 0) {1163 count = err;1164 goto errout;1165 }1166 count++;1167 }1168errout:1169 brelse(bh);1170 fscrypt_fname_free_buffer(&fname_crypto_str);1171 return count;1172}1173 1174 1175/*1176 * This function fills a red-black tree with information from a1177 * directory. We start scanning the directory in hash order, starting1178 * at start_hash and start_minor_hash.1179 *1180 * This function returns the number of entries inserted into the tree,1181 * or a negative error code.1182 */1183int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,1184 __u32 start_minor_hash, __u32 *next_hash)1185{1186 struct dx_hash_info hinfo;1187 struct ext4_dir_entry_2 *de;1188 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;1189 struct inode *dir;1190 ext4_lblk_t block;1191 int count = 0;1192 int ret, err;1193 __u32 hashval;1194 struct fscrypt_str tmp_str;1195 1196 dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",1197 start_hash, start_minor_hash));1198 dir = file_inode(dir_file);1199 if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) {1200 if (ext4_hash_in_dirent(dir))1201 hinfo.hash_version = DX_HASH_SIPHASH;1202 else1203 hinfo.hash_version =1204 EXT4_SB(dir->i_sb)->s_def_hash_version;1205 if (hinfo.hash_version <= DX_HASH_TEA)1206 hinfo.hash_version +=1207 EXT4_SB(dir->i_sb)->s_hash_unsigned;1208 hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;1209 if (ext4_has_inline_data(dir)) {1210 int has_inline_data = 1;1211 count = ext4_inlinedir_to_tree(dir_file, dir, 0,1212 &hinfo, start_hash,1213 start_minor_hash,1214 &has_inline_data);1215 if (has_inline_data) {1216 *next_hash = ~0;1217 return count;1218 }1219 }1220 count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,1221 start_hash, start_minor_hash);1222 *next_hash = ~0;1223 return count;1224 }1225 hinfo.hash = start_hash;1226 hinfo.minor_hash = 0;1227 frame = dx_probe(NULL, dir, &hinfo, frames);1228 if (IS_ERR(frame))1229 return PTR_ERR(frame);1230 1231 /* Add '.' and '..' from the htree header */1232 if (!start_hash && !start_minor_hash) {1233 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;1234 tmp_str.name = de->name;1235 tmp_str.len = de->name_len;1236 err = ext4_htree_store_dirent(dir_file, 0, 0,1237 de, &tmp_str);1238 if (err != 0)1239 goto errout;1240 count++;1241 }1242 if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {1243 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;1244 de = ext4_next_entry(de, dir->i_sb->s_blocksize);1245 tmp_str.name = de->name;1246 tmp_str.len = de->name_len;1247 err = ext4_htree_store_dirent(dir_file, 2, 0,1248 de, &tmp_str);1249 if (err != 0)1250 goto errout;1251 count++;1252 }1253 1254 while (1) {1255 if (fatal_signal_pending(current)) {1256 err = -ERESTARTSYS;1257 goto errout;1258 }1259 cond_resched();1260 block = dx_get_block(frame->at);1261 ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,1262 start_hash, start_minor_hash);1263 if (ret < 0) {1264 err = ret;1265 goto errout;1266 }1267 count += ret;1268 hashval = ~0;1269 ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,1270 frame, frames, &hashval);1271 *next_hash = hashval;1272 if (ret < 0) {1273 err = ret;1274 goto errout;1275 }1276 /*1277 * Stop if: (a) there are no more entries, or1278 * (b) we have inserted at least one entry and the1279 * next hash value is not a continuation1280 */1281 if ((ret == 0) ||1282 (count && ((hashval & 1) == 0)))1283 break;1284 }1285 dx_release(frames);1286 dxtrace(printk(KERN_DEBUG "Fill tree: returned %d entries, "1287 "next hash: %x\n", count, *next_hash));1288 return count;1289errout:1290 dx_release(frames);1291 return (err);1292}1293 1294static inline int search_dirblock(struct buffer_head *bh,1295 struct inode *dir,1296 struct ext4_filename *fname,1297 unsigned int offset,1298 struct ext4_dir_entry_2 **res_dir)1299{1300 return ext4_search_dir(bh, bh->b_data, dir->i_sb->s_blocksize, dir,1301 fname, offset, res_dir);1302}1303 1304/*1305 * Directory block splitting, compacting1306 */1307 1308/*1309 * Create map of hash values, offsets, and sizes, stored at end of block.1310 * Returns number of entries mapped.1311 */1312static int dx_make_map(struct inode *dir, struct buffer_head *bh,1313 struct dx_hash_info *hinfo,1314 struct dx_map_entry *map_tail)1315{1316 int count = 0;1317 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)bh->b_data;1318 unsigned int buflen = bh->b_size;1319 char *base = bh->b_data;1320 struct dx_hash_info h = *hinfo;1321 int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);1322 1323 if (ext4_has_metadata_csum(dir->i_sb))1324 buflen -= sizeof(struct ext4_dir_entry_tail);1325 1326 while ((char *) de < base + buflen) {1327 if (ext4_check_dir_entry(dir, NULL, de, bh, base, buflen,1328 ((char *)de) - base))1329 return -EFSCORRUPTED;1330 if (de->name_len && de->inode) {1331 if (ext4_hash_in_dirent(dir))1332 h.hash = EXT4_DIRENT_HASH(de);1333 else {1334 int err = ext4fs_dirhash(dir, de->name,1335 de->name_len, &h);1336 if (err < 0)1337 return err;1338 }1339 map_tail--;1340 map_tail->hash = h.hash;1341 map_tail->offs = ((char *) de - base)>>2;1342 map_tail->size = ext4_rec_len_from_disk(de->rec_len,1343 blocksize);1344 count++;1345 cond_resched();1346 }1347 de = ext4_next_entry(de, blocksize);1348 }1349 return count;1350}1351 1352/* Sort map by hash value */1353static void dx_sort_map (struct dx_map_entry *map, unsigned count)1354{1355 struct dx_map_entry *p, *q, *top = map + count - 1;1356 int more;1357 /* Combsort until bubble sort doesn't suck */1358 while (count > 2) {1359 count = count*10/13;1360 if (count - 9 < 2) /* 9, 10 -> 11 */1361 count = 11;1362 for (p = top, q = p - count; q >= map; p--, q--)1363 if (p->hash < q->hash)1364 swap(*p, *q);1365 }1366 /* Garden variety bubble sort */1367 do {1368 more = 0;1369 q = top;1370 while (q-- > map) {1371 if (q[1].hash >= q[0].hash)1372 continue;1373 swap(*(q+1), *q);1374 more = 1;1375 }1376 } while(more);1377}1378 1379static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)1380{1381 struct dx_entry *entries = frame->entries;1382 struct dx_entry *old = frame->at, *new = old + 1;1383 int count = dx_get_count(entries);1384 1385 ASSERT(count < dx_get_limit(entries));1386 ASSERT(old < entries + count);1387 memmove(new + 1, new, (char *)(entries + count) - (char *)(new));1388 dx_set_hash(new, hash);1389 dx_set_block(new, block);1390 dx_set_count(entries, count + 1);1391}1392 1393#if IS_ENABLED(CONFIG_UNICODE)1394int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,1395 struct ext4_filename *name)1396{1397 struct qstr *cf_name = &name->cf_name;1398 unsigned char *buf;1399 struct dx_hash_info *hinfo = &name->hinfo;1400 int len;1401 1402 if (!IS_CASEFOLDED(dir) ||1403 (IS_ENCRYPTED(dir) && !fscrypt_has_encryption_key(dir))) {1404 cf_name->name = NULL;1405 return 0;1406 }1407 1408 buf = kmalloc(EXT4_NAME_LEN, GFP_NOFS);1409 if (!buf)1410 return -ENOMEM;1411 1412 len = utf8_casefold(dir->i_sb->s_encoding, iname, buf, EXT4_NAME_LEN);1413 if (len <= 0) {1414 kfree(buf);1415 buf = NULL;1416 }1417 cf_name->name = buf;1418 cf_name->len = (unsigned) len;1419 1420 if (!IS_ENCRYPTED(dir))1421 return 0;1422 1423 hinfo->hash_version = DX_HASH_SIPHASH;1424 hinfo->seed = NULL;1425 if (cf_name->name)1426 return ext4fs_dirhash(dir, cf_name->name, cf_name->len, hinfo);1427 else1428 return ext4fs_dirhash(dir, iname->name, iname->len, hinfo);1429}1430#endif1431 1432/*1433 * Test whether a directory entry matches the filename being searched for.1434 *1435 * Return: %true if the directory entry matches, otherwise %false.1436 */1437static bool ext4_match(struct inode *parent,1438 const struct ext4_filename *fname,1439 struct ext4_dir_entry_2 *de)1440{1441 struct fscrypt_name f;1442 1443 if (!de->inode)1444 return false;1445 1446 f.usr_fname = fname->usr_fname;1447 f.disk_name = fname->disk_name;1448#ifdef CONFIG_FS_ENCRYPTION1449 f.crypto_buf = fname->crypto_buf;1450#endif1451 1452#if IS_ENABLED(CONFIG_UNICODE)1453 if (IS_CASEFOLDED(parent) &&1454 (!IS_ENCRYPTED(parent) || fscrypt_has_encryption_key(parent))) {1455 /*1456 * Just checking IS_ENCRYPTED(parent) below is not1457 * sufficient to decide whether one can use the hash for1458 * skipping the string comparison, because the key might1459 * have been added right after1460 * ext4_fname_setup_ci_filename(). In this case, a hash1461 * mismatch will be a false negative. Therefore, make1462 * sure cf_name was properly initialized before1463 * considering the calculated hash.1464 */1465 if (IS_ENCRYPTED(parent) && fname->cf_name.name &&1466 (fname->hinfo.hash != EXT4_DIRENT_HASH(de) ||1467 fname->hinfo.minor_hash != EXT4_DIRENT_MINOR_HASH(de)))1468 return false;1469 /*1470 * Treat comparison errors as not a match. The1471 * only case where it happens is on a disk1472 * corruption or ENOMEM.1473 */1474 1475 return generic_ci_match(parent, fname->usr_fname,1476 &fname->cf_name, de->name,1477 de->name_len) > 0;1478 }1479#endif1480 1481 return fscrypt_match_name(&f, de->name, de->name_len);1482}1483 1484/*1485 * Returns 0 if not found, -EFSCORRUPTED on failure, and 1 on success1486 */1487int ext4_search_dir(struct buffer_head *bh, char *search_buf, int buf_size,1488 struct inode *dir, struct ext4_filename *fname,1489 unsigned int offset, struct ext4_dir_entry_2 **res_dir)1490{1491 struct ext4_dir_entry_2 * de;1492 char * dlimit;1493 int de_len;1494 1495 de = (struct ext4_dir_entry_2 *)search_buf;1496 dlimit = search_buf + buf_size;1497 while ((char *) de < dlimit - EXT4_BASE_DIR_LEN) {1498 /* this code is executed quadratically often */1499 /* do minimal checking `by hand' */1500 if (de->name + de->name_len <= dlimit &&1501 ext4_match(dir, fname, de)) {1502 /* found a match - just to be sure, do1503 * a full check */1504 if (ext4_check_dir_entry(dir, NULL, de, bh, search_buf,1505 buf_size, offset))1506 return -EFSCORRUPTED;1507 *res_dir = de;1508 return 1;1509 }1510 /* prevent looping on a bad block */1511 de_len = ext4_rec_len_from_disk(de->rec_len,1512 dir->i_sb->s_blocksize);1513 if (de_len <= 0)1514 return -EFSCORRUPTED;1515 offset += de_len;1516 de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);1517 }1518 return 0;1519}1520 1521static int is_dx_internal_node(struct inode *dir, ext4_lblk_t block,1522 struct ext4_dir_entry *de)1523{1524 struct super_block *sb = dir->i_sb;1525 1526 if (!is_dx(dir))1527 return 0;1528 if (block == 0)1529 return 1;1530 if (de->inode == 0 &&1531 ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) ==1532 sb->s_blocksize)1533 return 1;1534 return 0;1535}1536 1537/*1538 * __ext4_find_entry()1539 *1540 * finds an entry in the specified directory with the wanted name. It1541 * returns the cache buffer in which the entry was found, and the entry1542 * itself (as a parameter - res_dir). It does NOT read the inode of the1543 * entry - you'll have to do that yourself if you want to.1544 *1545 * The returned buffer_head has ->b_count elevated. The caller is expected1546 * to brelse() it when appropriate.1547 */1548static struct buffer_head *__ext4_find_entry(struct inode *dir,1549 struct ext4_filename *fname,1550 struct ext4_dir_entry_2 **res_dir,1551 int *inlined)1552{1553 struct super_block *sb;1554 struct buffer_head *bh_use[NAMEI_RA_SIZE];1555 struct buffer_head *bh, *ret = NULL;1556 ext4_lblk_t start, block;1557 const u8 *name = fname->usr_fname->name;1558 size_t ra_max = 0; /* Number of bh's in the readahead1559 buffer, bh_use[] */1560 size_t ra_ptr = 0; /* Current index into readahead1561 buffer */1562 ext4_lblk_t nblocks;1563 int i, namelen, retval;1564 1565 *res_dir = NULL;1566 sb = dir->i_sb;1567 namelen = fname->usr_fname->len;1568 if (namelen > EXT4_NAME_LEN)1569 return NULL;1570 1571 if (ext4_has_inline_data(dir)) {1572 int has_inline_data = 1;1573 ret = ext4_find_inline_entry(dir, fname, res_dir,1574 &has_inline_data);1575 if (inlined)1576 *inlined = has_inline_data;1577 if (has_inline_data || IS_ERR(ret))1578 goto cleanup_and_exit;1579 }1580 1581 if ((namelen <= 2) && (name[0] == '.') &&1582 (name[1] == '.' || name[1] == '\0')) {1583 /*1584 * "." or ".." will only be in the first block1585 * NFS may look up ".."; "." should be handled by the VFS1586 */1587 block = start = 0;1588 nblocks = 1;1589 goto restart;1590 }1591 if (is_dx(dir)) {1592 ret = ext4_dx_find_entry(dir, fname, res_dir);1593 /*1594 * On success, or if the error was file not found,1595 * return. Otherwise, fall back to doing a search the1596 * old fashioned way.1597 */1598 if (!IS_ERR(ret) || PTR_ERR(ret) != ERR_BAD_DX_DIR)1599 goto cleanup_and_exit;1600 dxtrace(printk(KERN_DEBUG "ext4_find_entry: dx failed, "1601 "falling back\n"));1602 ret = NULL;1603 }1604 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);1605 if (!nblocks) {1606 ret = NULL;1607 goto cleanup_and_exit;1608 }1609 start = EXT4_I(dir)->i_dir_start_lookup;1610 if (start >= nblocks)1611 start = 0;1612 block = start;1613restart:1614 do {1615 /*1616 * We deal with the read-ahead logic here.1617 */1618 cond_resched();1619 if (ra_ptr >= ra_max) {1620 /* Refill the readahead buffer */1621 ra_ptr = 0;1622 if (block < start)1623 ra_max = start - block;1624 else1625 ra_max = nblocks - block;1626 ra_max = min(ra_max, ARRAY_SIZE(bh_use));1627 retval = ext4_bread_batch(dir, block, ra_max,1628 false /* wait */, bh_use);1629 if (retval) {1630 ret = ERR_PTR(retval);1631 ra_max = 0;1632 goto cleanup_and_exit;1633 }1634 }1635 if ((bh = bh_use[ra_ptr++]) == NULL)1636 goto next;1637 wait_on_buffer(bh);1638 if (!buffer_uptodate(bh)) {1639 EXT4_ERROR_INODE_ERR(dir, EIO,1640 "reading directory lblock %lu",1641 (unsigned long) block);1642 brelse(bh);1643 ret = ERR_PTR(-EIO);1644 goto cleanup_and_exit;1645 }1646 if (!buffer_verified(bh) &&1647 !is_dx_internal_node(dir, block,1648 (struct ext4_dir_entry *)bh->b_data) &&1649 !ext4_dirblock_csum_verify(dir, bh)) {1650 EXT4_ERROR_INODE_ERR(dir, EFSBADCRC,1651 "checksumming directory "1652 "block %lu", (unsigned long)block);1653 brelse(bh);1654 ret = ERR_PTR(-EFSBADCRC);1655 goto cleanup_and_exit;1656 }1657 set_buffer_verified(bh);1658 i = search_dirblock(bh, dir, fname,1659 block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);1660 if (i == 1) {1661 EXT4_I(dir)->i_dir_start_lookup = block;1662 ret = bh;1663 goto cleanup_and_exit;1664 } else {1665 brelse(bh);1666 if (i < 0) {1667 ret = ERR_PTR(i);1668 goto cleanup_and_exit;1669 }1670 }1671 next:1672 if (++block >= nblocks)1673 block = 0;1674 } while (block != start);1675 1676 /*1677 * If the directory has grown while we were searching, then1678 * search the last part of the directory before giving up.1679 */1680 block = nblocks;1681 nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);1682 if (block < nblocks) {1683 start = 0;1684 goto restart;1685 }1686 1687cleanup_and_exit:1688 /* Clean up the read-ahead blocks */1689 for (; ra_ptr < ra_max; ra_ptr++)1690 brelse(bh_use[ra_ptr]);1691 return ret;1692}1693 1694static struct buffer_head *ext4_find_entry(struct inode *dir,1695 const struct qstr *d_name,1696 struct ext4_dir_entry_2 **res_dir,1697 int *inlined)1698{1699 int err;1700 struct ext4_filename fname;1701 struct buffer_head *bh;1702 1703 err = ext4_fname_setup_filename(dir, d_name, 1, &fname);1704 if (err == -ENOENT)1705 return NULL;1706 if (err)1707 return ERR_PTR(err);1708 1709 bh = __ext4_find_entry(dir, &fname, res_dir, inlined);1710 1711 ext4_fname_free_filename(&fname);1712 return bh;1713}1714 1715static struct buffer_head *ext4_lookup_entry(struct inode *dir,1716 struct dentry *dentry,1717 struct ext4_dir_entry_2 **res_dir)1718{1719 int err;1720 struct ext4_filename fname;1721 struct buffer_head *bh;1722 1723 err = ext4_fname_prepare_lookup(dir, dentry, &fname);1724 if (err == -ENOENT)1725 return NULL;1726 if (err)1727 return ERR_PTR(err);1728 1729 bh = __ext4_find_entry(dir, &fname, res_dir, NULL);1730 1731 ext4_fname_free_filename(&fname);1732 return bh;1733}1734 1735static struct buffer_head * ext4_dx_find_entry(struct inode *dir,1736 struct ext4_filename *fname,1737 struct ext4_dir_entry_2 **res_dir)1738{1739 struct super_block * sb = dir->i_sb;1740 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;1741 struct buffer_head *bh;1742 ext4_lblk_t block;1743 int retval;1744 1745#ifdef CONFIG_FS_ENCRYPTION1746 *res_dir = NULL;1747#endif1748 frame = dx_probe(fname, dir, NULL, frames);1749 if (IS_ERR(frame))1750 return (struct buffer_head *) frame;1751 do {1752 block = dx_get_block(frame->at);1753 bh = ext4_read_dirblock(dir, block, DIRENT_HTREE);1754 if (IS_ERR(bh))1755 goto errout;1756 1757 retval = search_dirblock(bh, dir, fname,1758 block << EXT4_BLOCK_SIZE_BITS(sb),1759 res_dir);1760 if (retval == 1)1761 goto success;1762 brelse(bh);1763 if (retval < 0) {1764 bh = ERR_PTR(ERR_BAD_DX_DIR);1765 goto errout;1766 }1767 1768 /* Check to see if we should continue to search */1769 retval = ext4_htree_next_block(dir, fname->hinfo.hash, frame,1770 frames, NULL);1771 if (retval < 0) {1772 ext4_warning_inode(dir,1773 "error %d reading directory index block",1774 retval);1775 bh = ERR_PTR(retval);1776 goto errout;1777 }1778 } while (retval == 1);1779 1780 bh = NULL;1781errout:1782 dxtrace(printk(KERN_DEBUG "%s not found\n", fname->usr_fname->name));1783success:1784 dx_release(frames);1785 return bh;1786}1787 1788static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)1789{1790 struct inode *inode;1791 struct ext4_dir_entry_2 *de;1792 struct buffer_head *bh;1793 1794 if (dentry->d_name.len > EXT4_NAME_LEN)1795 return ERR_PTR(-ENAMETOOLONG);1796 1797 bh = ext4_lookup_entry(dir, dentry, &de);1798 if (IS_ERR(bh))1799 return ERR_CAST(bh);1800 inode = NULL;1801 if (bh) {1802 __u32 ino = le32_to_cpu(de->inode);1803 brelse(bh);1804 if (!ext4_valid_inum(dir->i_sb, ino)) {1805 EXT4_ERROR_INODE(dir, "bad inode number: %u", ino);1806 return ERR_PTR(-EFSCORRUPTED);1807 }1808 if (unlikely(ino == dir->i_ino)) {1809 EXT4_ERROR_INODE(dir, "'%pd' linked to parent dir",1810 dentry);1811 return ERR_PTR(-EFSCORRUPTED);1812 }1813 inode = ext4_iget(dir->i_sb, ino, EXT4_IGET_NORMAL);1814 if (inode == ERR_PTR(-ESTALE)) {1815 EXT4_ERROR_INODE(dir,1816 "deleted inode referenced: %u",1817 ino);1818 return ERR_PTR(-EFSCORRUPTED);1819 }1820 if (!IS_ERR(inode) && IS_ENCRYPTED(dir) &&1821 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&1822 !fscrypt_has_permitted_context(dir, inode)) {1823 ext4_warning(inode->i_sb,1824 "Inconsistent encryption contexts: %lu/%lu",1825 dir->i_ino, inode->i_ino);1826 iput(inode);1827 return ERR_PTR(-EPERM);1828 }1829 }1830 1831 if (IS_ENABLED(CONFIG_UNICODE) && !inode && IS_CASEFOLDED(dir)) {1832 /* Eventually we want to call d_add_ci(dentry, NULL)1833 * for negative dentries in the encoding case as1834 * well. For now, prevent the negative dentry1835 * from being cached.1836 */1837 return NULL;1838 }1839 1840 return d_splice_alias(inode, dentry);1841}1842 1843 1844struct dentry *ext4_get_parent(struct dentry *child)1845{1846 __u32 ino;1847 struct ext4_dir_entry_2 * de;1848 struct buffer_head *bh;1849 1850 bh = ext4_find_entry(d_inode(child), &dotdot_name, &de, NULL);1851 if (IS_ERR(bh))1852 return ERR_CAST(bh);1853 if (!bh)1854 return ERR_PTR(-ENOENT);1855 ino = le32_to_cpu(de->inode);1856 brelse(bh);1857 1858 if (!ext4_valid_inum(child->d_sb, ino)) {1859 EXT4_ERROR_INODE(d_inode(child),1860 "bad parent inode number: %u", ino);1861 return ERR_PTR(-EFSCORRUPTED);1862 }1863 1864 return d_obtain_alias(ext4_iget(child->d_sb, ino, EXT4_IGET_NORMAL));1865}1866 1867/*1868 * Move count entries from end of map between two memory locations.1869 * Returns pointer to last entry moved.1870 */1871static struct ext4_dir_entry_2 *1872dx_move_dirents(struct inode *dir, char *from, char *to,1873 struct dx_map_entry *map, int count,1874 unsigned blocksize)1875{1876 unsigned rec_len = 0;1877 1878 while (count--) {1879 struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *)1880 (from + (map->offs<<2));1881 rec_len = ext4_dir_rec_len(de->name_len, dir);1882 1883 memcpy (to, de, rec_len);1884 ((struct ext4_dir_entry_2 *) to)->rec_len =1885 ext4_rec_len_to_disk(rec_len, blocksize);1886 1887 /* wipe dir_entry excluding the rec_len field */1888 de->inode = 0;1889 memset(&de->name_len, 0, ext4_rec_len_from_disk(de->rec_len,1890 blocksize) -1891 offsetof(struct ext4_dir_entry_2,1892 name_len));1893 1894 map++;1895 to += rec_len;1896 }1897 return (struct ext4_dir_entry_2 *) (to - rec_len);1898}1899 1900/*1901 * Compact each dir entry in the range to the minimal rec_len.1902 * Returns pointer to last entry in range.1903 */1904static struct ext4_dir_entry_2 *dx_pack_dirents(struct inode *dir, char *base,1905 unsigned int blocksize)1906{1907 struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;1908 unsigned rec_len = 0;1909 1910 prev = to = de;1911 while ((char*)de < base + blocksize) {1912 next = ext4_next_entry(de, blocksize);1913 if (de->inode && de->name_len) {1914 rec_len = ext4_dir_rec_len(de->name_len, dir);1915 if (de > to)1916 memmove(to, de, rec_len);1917 to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);1918 prev = to;1919 to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);1920 }1921 de = next;1922 }1923 return prev;1924}1925 1926/*1927 * Split a full leaf block to make room for a new dir entry.1928 * Allocate a new block, and move entries so that they are approx. equally full.1929 * Returns pointer to de in block into which the new entry will be inserted.1930 */1931static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,1932 struct buffer_head **bh,struct dx_frame *frame,1933 struct dx_hash_info *hinfo)1934{1935 unsigned blocksize = dir->i_sb->s_blocksize;1936 unsigned continued;1937 int count;1938 struct buffer_head *bh2;1939 ext4_lblk_t newblock;1940 u32 hash2;1941 struct dx_map_entry *map;1942 char *data1 = (*bh)->b_data, *data2;1943 unsigned split, move, size;1944 struct ext4_dir_entry_2 *de = NULL, *de2;1945 int csum_size = 0;1946 int err = 0, i;1947 1948 if (ext4_has_metadata_csum(dir->i_sb))1949 csum_size = sizeof(struct ext4_dir_entry_tail);1950 1951 bh2 = ext4_append(handle, dir, &newblock);1952 if (IS_ERR(bh2)) {1953 brelse(*bh);1954 *bh = NULL;1955 return (struct ext4_dir_entry_2 *) bh2;1956 }1957 1958 BUFFER_TRACE(*bh, "get_write_access");1959 err = ext4_journal_get_write_access(handle, dir->i_sb, *bh,1960 EXT4_JTR_NONE);1961 if (err)1962 goto journal_error;1963 1964 BUFFER_TRACE(frame->bh, "get_write_access");1965 err = ext4_journal_get_write_access(handle, dir->i_sb, frame->bh,1966 EXT4_JTR_NONE);1967 if (err)1968 goto journal_error;1969 1970 data2 = bh2->b_data;1971 1972 /* create map in the end of data2 block */1973 map = (struct dx_map_entry *) (data2 + blocksize);1974 count = dx_make_map(dir, *bh, hinfo, map);1975 if (count < 0) {1976 err = count;1977 goto journal_error;1978 }1979 map -= count;1980 dx_sort_map(map, count);1981 /* Ensure that neither split block is over half full */1982 size = 0;1983 move = 0;1984 for (i = count-1; i >= 0; i--) {1985 /* is more than half of this entry in 2nd half of the block? */1986 if (size + map[i].size/2 > blocksize/2)1987 break;1988 size += map[i].size;1989 move++;1990 }1991 /*1992 * map index at which we will split1993 *1994 * If the sum of active entries didn't exceed half the block size, just1995 * split it in half by count; each resulting block will have at least1996 * half the space free.1997 */1998 if (i > 0)1999 split = count - move;2000 else2001 split = count/2;2002 2003 hash2 = map[split].hash;2004 continued = split > 0 ? hash2 == map[split - 1].hash : 0;2005 dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n",2006 (unsigned long)dx_get_block(frame->at),2007 hash2, split, count-split));2008 2009 /* Fancy dance to stay within two buffers */2010 de2 = dx_move_dirents(dir, data1, data2, map + split, count - split,2011 blocksize);2012 de = dx_pack_dirents(dir, data1, blocksize);2013 de->rec_len = ext4_rec_len_to_disk(data1 + (blocksize - csum_size) -2014 (char *) de,2015 blocksize);2016 de2->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -2017 (char *) de2,2018 blocksize);2019 if (csum_size) {2020 ext4_initialize_dirent_tail(*bh, blocksize);2021 ext4_initialize_dirent_tail(bh2, blocksize);2022 }2023 2024 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data1,2025 blocksize, 1));2026 dxtrace(dx_show_leaf(dir, hinfo, (struct ext4_dir_entry_2 *) data2,2027 blocksize, 1));2028 2029 /* Which block gets the new entry? */2030 if (hinfo->hash >= hash2) {2031 swap(*bh, bh2);2032 de = de2;2033 }2034 dx_insert_block(frame, hash2 + continued, newblock);2035 err = ext4_handle_dirty_dirblock(handle, dir, bh2);2036 if (err)2037 goto journal_error;2038 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);2039 if (err)2040 goto journal_error;2041 brelse(bh2);2042 dxtrace(dx_show_index("frame", frame->entries));2043 return de;2044 2045journal_error:2046 brelse(*bh);2047 brelse(bh2);2048 *bh = NULL;2049 ext4_std_error(dir->i_sb, err);2050 return ERR_PTR(err);2051}2052 2053int ext4_find_dest_de(struct inode *dir, struct inode *inode,2054 struct buffer_head *bh,2055 void *buf, int buf_size,2056 struct ext4_filename *fname,2057 struct ext4_dir_entry_2 **dest_de)2058{2059 struct ext4_dir_entry_2 *de;2060 unsigned short reclen = ext4_dir_rec_len(fname_len(fname), dir);2061 int nlen, rlen;2062 unsigned int offset = 0;2063 char *top;2064 2065 de = buf;2066 top = buf + buf_size - reclen;2067 while ((char *) de <= top) {2068 if (ext4_check_dir_entry(dir, NULL, de, bh,2069 buf, buf_size, offset))2070 return -EFSCORRUPTED;2071 if (ext4_match(dir, fname, de))2072 return -EEXIST;2073 nlen = ext4_dir_rec_len(de->name_len, dir);2074 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);2075 if ((de->inode ? rlen - nlen : rlen) >= reclen)2076 break;2077 de = (struct ext4_dir_entry_2 *)((char *)de + rlen);2078 offset += rlen;2079 }2080 if ((char *) de > top)2081 return -ENOSPC;2082 2083 *dest_de = de;2084 return 0;2085}2086 2087void ext4_insert_dentry(struct inode *dir,2088 struct inode *inode,2089 struct ext4_dir_entry_2 *de,2090 int buf_size,2091 struct ext4_filename *fname)2092{2093 2094 int nlen, rlen;2095 2096 nlen = ext4_dir_rec_len(de->name_len, dir);2097 rlen = ext4_rec_len_from_disk(de->rec_len, buf_size);2098 if (de->inode) {2099 struct ext4_dir_entry_2 *de1 =2100 (struct ext4_dir_entry_2 *)((char *)de + nlen);2101 de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size);2102 de->rec_len = ext4_rec_len_to_disk(nlen, buf_size);2103 de = de1;2104 }2105 de->file_type = EXT4_FT_UNKNOWN;2106 de->inode = cpu_to_le32(inode->i_ino);2107 ext4_set_de_type(inode->i_sb, de, inode->i_mode);2108 de->name_len = fname_len(fname);2109 memcpy(de->name, fname_name(fname), fname_len(fname));2110 if (ext4_hash_in_dirent(dir)) {2111 struct dx_hash_info *hinfo = &fname->hinfo;2112 2113 EXT4_DIRENT_HASHES(de)->hash = cpu_to_le32(hinfo->hash);2114 EXT4_DIRENT_HASHES(de)->minor_hash =2115 cpu_to_le32(hinfo->minor_hash);2116 }2117}2118 2119/*2120 * Add a new entry into a directory (leaf) block. If de is non-NULL,2121 * it points to a directory entry which is guaranteed to be large2122 * enough for new directory entry. If de is NULL, then2123 * add_dirent_to_buf will attempt search the directory block for2124 * space. It will return -ENOSPC if no space is available, and -EIO2125 * and -EEXIST if directory entry already exists.2126 */2127static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,2128 struct inode *dir,2129 struct inode *inode, struct ext4_dir_entry_2 *de,2130 struct buffer_head *bh)2131{2132 unsigned int blocksize = dir->i_sb->s_blocksize;2133 int csum_size = 0;2134 int err, err2;2135 2136 if (ext4_has_metadata_csum(inode->i_sb))2137 csum_size = sizeof(struct ext4_dir_entry_tail);2138 2139 if (!de) {2140 err = ext4_find_dest_de(dir, inode, bh, bh->b_data,2141 blocksize - csum_size, fname, &de);2142 if (err)2143 return err;2144 }2145 BUFFER_TRACE(bh, "get_write_access");2146 err = ext4_journal_get_write_access(handle, dir->i_sb, bh,2147 EXT4_JTR_NONE);2148 if (err) {2149 ext4_std_error(dir->i_sb, err);2150 return err;2151 }2152 2153 /* By now the buffer is marked for journaling */2154 ext4_insert_dentry(dir, inode, de, blocksize, fname);2155 2156 /*2157 * XXX shouldn't update any times until successful2158 * completion of syscall, but too many callers depend2159 * on this.2160 *2161 * XXX similarly, too many callers depend on2162 * ext4_new_inode() setting the times, but error2163 * recovery deletes the inode, so the worst that can2164 * happen is that the times are slightly out of date2165 * and/or different from the directory change time.2166 */2167 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));2168 ext4_update_dx_flag(dir);2169 inode_inc_iversion(dir);2170 err2 = ext4_mark_inode_dirty(handle, dir);2171 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");2172 err = ext4_handle_dirty_dirblock(handle, dir, bh);2173 if (err)2174 ext4_std_error(dir->i_sb, err);2175 return err ? err : err2;2176}2177 2178static bool ext4_check_dx_root(struct inode *dir, struct dx_root *root)2179{2180 struct fake_dirent *fde;2181 const char *error_msg;2182 unsigned int rlen;2183 unsigned int blocksize = dir->i_sb->s_blocksize;2184 char *blockend = (char *)root + dir->i_sb->s_blocksize;2185 2186 fde = &root->dot;2187 if (unlikely(fde->name_len != 1)) {2188 error_msg = "invalid name_len for '.'";2189 goto corrupted;2190 }2191 if (unlikely(strncmp(root->dot_name, ".", fde->name_len))) {2192 error_msg = "invalid name for '.'";2193 goto corrupted;2194 }2195 rlen = ext4_rec_len_from_disk(fde->rec_len, blocksize);2196 if (unlikely((char *)fde + rlen >= blockend)) {2197 error_msg = "invalid rec_len for '.'";2198 goto corrupted;2199 }2200 2201 fde = &root->dotdot;2202 if (unlikely(fde->name_len != 2)) {2203 error_msg = "invalid name_len for '..'";2204 goto corrupted;2205 }2206 if (unlikely(strncmp(root->dotdot_name, "..", fde->name_len))) {2207 error_msg = "invalid name for '..'";2208 goto corrupted;2209 }2210 rlen = ext4_rec_len_from_disk(fde->rec_len, blocksize);2211 if (unlikely((char *)fde + rlen >= blockend)) {2212 error_msg = "invalid rec_len for '..'";2213 goto corrupted;2214 }2215 2216 return true;2217 2218corrupted:2219 EXT4_ERROR_INODE(dir, "Corrupt dir, %s, running e2fsck is recommended",2220 error_msg);2221 return false;2222}2223 2224/*2225 * This converts a one block unindexed directory to a 3 block indexed2226 * directory, and adds the dentry to the indexed directory.2227 */2228static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,2229 struct inode *dir,2230 struct inode *inode, struct buffer_head *bh)2231{2232 struct buffer_head *bh2;2233 struct dx_root *root;2234 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;2235 struct dx_entry *entries;2236 struct ext4_dir_entry_2 *de, *de2;2237 char *data2, *top;2238 unsigned len;2239 int retval;2240 unsigned blocksize;2241 ext4_lblk_t block;2242 struct fake_dirent *fde;2243 int csum_size = 0;2244 2245 if (ext4_has_metadata_csum(inode->i_sb))2246 csum_size = sizeof(struct ext4_dir_entry_tail);2247 2248 blocksize = dir->i_sb->s_blocksize;2249 dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino));2250 BUFFER_TRACE(bh, "get_write_access");2251 retval = ext4_journal_get_write_access(handle, dir->i_sb, bh,2252 EXT4_JTR_NONE);2253 if (retval) {2254 ext4_std_error(dir->i_sb, retval);2255 brelse(bh);2256 return retval;2257 }2258 2259 root = (struct dx_root *) bh->b_data;2260 if (!ext4_check_dx_root(dir, root)) {2261 brelse(bh);2262 return -EFSCORRUPTED;2263 }2264 2265 /* The 0th block becomes the root, move the dirents out */2266 fde = &root->dotdot;2267 de = (struct ext4_dir_entry_2 *)((char *)fde +2268 ext4_rec_len_from_disk(fde->rec_len, blocksize));2269 len = ((char *) root) + (blocksize - csum_size) - (char *) de;2270 2271 /* Allocate new block for the 0th block's dirents */2272 bh2 = ext4_append(handle, dir, &block);2273 if (IS_ERR(bh2)) {2274 brelse(bh);2275 return PTR_ERR(bh2);2276 }2277 ext4_set_inode_flag(dir, EXT4_INODE_INDEX);2278 data2 = bh2->b_data;2279 2280 memcpy(data2, de, len);2281 memset(de, 0, len); /* wipe old data */2282 de = (struct ext4_dir_entry_2 *) data2;2283 top = data2 + len;2284 while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) {2285 if (ext4_check_dir_entry(dir, NULL, de, bh2, data2, len,2286 (char *)de - data2)) {2287 brelse(bh2);2288 brelse(bh);2289 return -EFSCORRUPTED;2290 }2291 de = de2;2292 }2293 de->rec_len = ext4_rec_len_to_disk(data2 + (blocksize - csum_size) -2294 (char *) de, blocksize);2295 2296 if (csum_size)2297 ext4_initialize_dirent_tail(bh2, blocksize);2298 2299 /* Initialize the root; the dot dirents already exist */2300 de = (struct ext4_dir_entry_2 *) (&root->dotdot);2301 de->rec_len = ext4_rec_len_to_disk(2302 blocksize - ext4_dir_rec_len(2, NULL), blocksize);2303 memset (&root->info, 0, sizeof(root->info));2304 root->info.info_length = sizeof(root->info);2305 if (ext4_hash_in_dirent(dir))2306 root->info.hash_version = DX_HASH_SIPHASH;2307 else2308 root->info.hash_version =2309 EXT4_SB(dir->i_sb)->s_def_hash_version;2310 2311 entries = root->entries;2312 dx_set_block(entries, 1);2313 dx_set_count(entries, 1);2314 dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info)));2315 2316 /* Initialize as for dx_probe */2317 fname->hinfo.hash_version = root->info.hash_version;2318 if (fname->hinfo.hash_version <= DX_HASH_TEA)2319 fname->hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned;2320 fname->hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;2321 2322 /* casefolded encrypted hashes are computed on fname setup */2323 if (!ext4_hash_in_dirent(dir)) {2324 int err = ext4fs_dirhash(dir, fname_name(fname),2325 fname_len(fname), &fname->hinfo);2326 if (err < 0) {2327 brelse(bh2);2328 brelse(bh);2329 return err;2330 }2331 }2332 memset(frames, 0, sizeof(frames));2333 frame = frames;2334 frame->entries = entries;2335 frame->at = entries;2336 frame->bh = bh;2337 2338 retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);2339 if (retval)2340 goto out_frames;2341 retval = ext4_handle_dirty_dirblock(handle, dir, bh2);2342 if (retval)2343 goto out_frames;2344 2345 de = do_split(handle,dir, &bh2, frame, &fname->hinfo);2346 if (IS_ERR(de)) {2347 retval = PTR_ERR(de);2348 goto out_frames;2349 }2350 2351 retval = add_dirent_to_buf(handle, fname, dir, inode, de, bh2);2352out_frames:2353 /*2354 * Even if the block split failed, we have to properly write2355 * out all the changes we did so far. Otherwise we can end up2356 * with corrupted filesystem.2357 */2358 if (retval)2359 ext4_mark_inode_dirty(handle, dir);2360 dx_release(frames);2361 brelse(bh2);2362 return retval;2363}2364 2365/*2366 * ext4_add_entry()2367 *2368 * adds a file entry to the specified directory, using the same2369 * semantics as ext4_find_entry(). It returns NULL if it failed.2370 *2371 * NOTE!! The inode part of 'de' is left at 0 - which means you2372 * may not sleep between calling this and putting something into2373 * the entry, as someone else might have used it while you slept.2374 */2375static int ext4_add_entry(handle_t *handle, struct dentry *dentry,2376 struct inode *inode)2377{2378 struct inode *dir = d_inode(dentry->d_parent);2379 struct buffer_head *bh = NULL;2380 struct ext4_dir_entry_2 *de;2381 struct super_block *sb;2382 struct ext4_filename fname;2383 int retval;2384 int dx_fallback=0;2385 unsigned blocksize;2386 ext4_lblk_t block, blocks;2387 int csum_size = 0;2388 2389 if (ext4_has_metadata_csum(inode->i_sb))2390 csum_size = sizeof(struct ext4_dir_entry_tail);2391 2392 sb = dir->i_sb;2393 blocksize = sb->s_blocksize;2394 2395 if (fscrypt_is_nokey_name(dentry))2396 return -ENOKEY;2397 2398#if IS_ENABLED(CONFIG_UNICODE)2399 if (sb_has_strict_encoding(sb) && IS_CASEFOLDED(dir) &&2400 utf8_validate(sb->s_encoding, &dentry->d_name))2401 return -EINVAL;2402#endif2403 2404 retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);2405 if (retval)2406 return retval;2407 2408 if (ext4_has_inline_data(dir)) {2409 retval = ext4_try_add_inline_entry(handle, &fname, dir, inode);2410 if (retval < 0)2411 goto out;2412 if (retval == 1) {2413 retval = 0;2414 goto out;2415 }2416 }2417 2418 if (is_dx(dir)) {2419 retval = ext4_dx_add_entry(handle, &fname, dir, inode);2420 if (!retval || (retval != ERR_BAD_DX_DIR))2421 goto out;2422 /* Can we just ignore htree data? */2423 if (ext4_has_metadata_csum(sb)) {2424 EXT4_ERROR_INODE(dir,2425 "Directory has corrupted htree index.");2426 retval = -EFSCORRUPTED;2427 goto out;2428 }2429 ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);2430 dx_fallback++;2431 retval = ext4_mark_inode_dirty(handle, dir);2432 if (unlikely(retval))2433 goto out;2434 }2435 blocks = dir->i_size >> sb->s_blocksize_bits;2436 for (block = 0; block < blocks; block++) {2437 bh = ext4_read_dirblock(dir, block, DIRENT);2438 if (bh == NULL) {2439 bh = ext4_bread(handle, dir, block,2440 EXT4_GET_BLOCKS_CREATE);2441 goto add_to_new_block;2442 }2443 if (IS_ERR(bh)) {2444 retval = PTR_ERR(bh);2445 bh = NULL;2446 goto out;2447 }2448 retval = add_dirent_to_buf(handle, &fname, dir, inode,2449 NULL, bh);2450 if (retval != -ENOSPC)2451 goto out;2452 2453 if (blocks == 1 && !dx_fallback &&2454 ext4_has_feature_dir_index(sb)) {2455 retval = make_indexed_dir(handle, &fname, dir,2456 inode, bh);2457 bh = NULL; /* make_indexed_dir releases bh */2458 goto out;2459 }2460 brelse(bh);2461 }2462 bh = ext4_append(handle, dir, &block);2463add_to_new_block:2464 if (IS_ERR(bh)) {2465 retval = PTR_ERR(bh);2466 bh = NULL;2467 goto out;2468 }2469 de = (struct ext4_dir_entry_2 *) bh->b_data;2470 de->inode = 0;2471 de->rec_len = ext4_rec_len_to_disk(blocksize - csum_size, blocksize);2472 2473 if (csum_size)2474 ext4_initialize_dirent_tail(bh, blocksize);2475 2476 retval = add_dirent_to_buf(handle, &fname, dir, inode, de, bh);2477out:2478 ext4_fname_free_filename(&fname);2479 brelse(bh);2480 if (retval == 0)2481 ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);2482 return retval;2483}2484 2485/*2486 * Returns 0 for success, or a negative error value2487 */2488static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,2489 struct inode *dir, struct inode *inode)2490{2491 struct dx_frame frames[EXT4_HTREE_LEVEL], *frame;2492 struct dx_entry *entries, *at;2493 struct buffer_head *bh;2494 struct super_block *sb = dir->i_sb;2495 struct ext4_dir_entry_2 *de;2496 int restart;2497 int err;2498 2499again:2500 restart = 0;2501 frame = dx_probe(fname, dir, NULL, frames);2502 if (IS_ERR(frame))2503 return PTR_ERR(frame);2504 entries = frame->entries;2505 at = frame->at;2506 bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT_HTREE);2507 if (IS_ERR(bh)) {2508 err = PTR_ERR(bh);2509 bh = NULL;2510 goto cleanup;2511 }2512 2513 BUFFER_TRACE(bh, "get_write_access");2514 err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);2515 if (err)2516 goto journal_error;2517 2518 err = add_dirent_to_buf(handle, fname, dir, inode, NULL, bh);2519 if (err != -ENOSPC)2520 goto cleanup;2521 2522 err = 0;2523 /* Block full, should compress but for now just split */2524 dxtrace(printk(KERN_DEBUG "using %u of %u node entries\n",2525 dx_get_count(entries), dx_get_limit(entries)));2526 /* Need to split index? */2527 if (dx_get_count(entries) == dx_get_limit(entries)) {2528 ext4_lblk_t newblock;2529 int levels = frame - frames + 1;2530 unsigned int icount;2531 int add_level = 1;2532 struct dx_entry *entries2;2533 struct dx_node *node2;2534 struct buffer_head *bh2;2535 2536 while (frame > frames) {2537 if (dx_get_count((frame - 1)->entries) <2538 dx_get_limit((frame - 1)->entries)) {2539 add_level = 0;2540 break;2541 }2542 frame--; /* split higher index block */2543 at = frame->at;2544 entries = frame->entries;2545 restart = 1;2546 }2547 if (add_level && levels == ext4_dir_htree_level(sb)) {2548 ext4_warning(sb, "Directory (ino: %lu) index full, "2549 "reach max htree level :%d",2550 dir->i_ino, levels);2551 if (ext4_dir_htree_level(sb) < EXT4_HTREE_LEVEL) {2552 ext4_warning(sb, "Large directory feature is "2553 "not enabled on this "2554 "filesystem");2555 }2556 err = -ENOSPC;2557 goto cleanup;2558 }2559 icount = dx_get_count(entries);2560 bh2 = ext4_append(handle, dir, &newblock);2561 if (IS_ERR(bh2)) {2562 err = PTR_ERR(bh2);2563 goto cleanup;2564 }2565 node2 = (struct dx_node *)(bh2->b_data);2566 entries2 = node2->entries;2567 memset(&node2->fake, 0, sizeof(struct fake_dirent));2568 node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,2569 sb->s_blocksize);2570 BUFFER_TRACE(frame->bh, "get_write_access");2571 err = ext4_journal_get_write_access(handle, sb, frame->bh,2572 EXT4_JTR_NONE);2573 if (err)2574 goto journal_error;2575 if (!add_level) {2576 unsigned icount1 = icount/2, icount2 = icount - icount1;2577 unsigned hash2 = dx_get_hash(entries + icount1);2578 dxtrace(printk(KERN_DEBUG "Split index %i/%i\n",2579 icount1, icount2));2580 2581 BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */2582 err = ext4_journal_get_write_access(handle, sb,2583 (frame - 1)->bh,2584 EXT4_JTR_NONE);2585 if (err)2586 goto journal_error;2587 2588 memcpy((char *) entries2, (char *) (entries + icount1),2589 icount2 * sizeof(struct dx_entry));2590 dx_set_count(entries, icount1);2591 dx_set_count(entries2, icount2);2592 dx_set_limit(entries2, dx_node_limit(dir));2593 2594 /* Which index block gets the new entry? */2595 if (at - entries >= icount1) {2596 frame->at = at - entries - icount1 + entries2;2597 frame->entries = entries = entries2;2598 swap(frame->bh, bh2);2599 }2600 dx_insert_block((frame - 1), hash2, newblock);2601 dxtrace(dx_show_index("node", frame->entries));2602 dxtrace(dx_show_index("node",2603 ((struct dx_node *) bh2->b_data)->entries));2604 err = ext4_handle_dirty_dx_node(handle, dir, bh2);2605 if (err)2606 goto journal_error;2607 brelse (bh2);2608 err = ext4_handle_dirty_dx_node(handle, dir,2609 (frame - 1)->bh);2610 if (err)2611 goto journal_error;2612 err = ext4_handle_dirty_dx_node(handle, dir,2613 frame->bh);2614 if (restart || err)2615 goto journal_error;2616 } else {2617 struct dx_root *dxroot;2618 memcpy((char *) entries2, (char *) entries,2619 icount * sizeof(struct dx_entry));2620 dx_set_limit(entries2, dx_node_limit(dir));2621 2622 /* Set up root */2623 dx_set_count(entries, 1);2624 dx_set_block(entries + 0, newblock);2625 dxroot = (struct dx_root *)frames[0].bh->b_data;2626 dxroot->info.indirect_levels += 1;2627 dxtrace(printk(KERN_DEBUG2628 "Creating %d level index...\n",2629 dxroot->info.indirect_levels));2630 err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);2631 if (err)2632 goto journal_error;2633 err = ext4_handle_dirty_dx_node(handle, dir, bh2);2634 brelse(bh2);2635 restart = 1;2636 goto journal_error;2637 }2638 }2639 de = do_split(handle, dir, &bh, frame, &fname->hinfo);2640 if (IS_ERR(de)) {2641 err = PTR_ERR(de);2642 goto cleanup;2643 }2644 err = add_dirent_to_buf(handle, fname, dir, inode, de, bh);2645 goto cleanup;2646 2647journal_error:2648 ext4_std_error(dir->i_sb, err); /* this is a no-op if err == 0 */2649cleanup:2650 brelse(bh);2651 dx_release(frames);2652 /* @restart is true means htree-path has been changed, we need to2653 * repeat dx_probe() to find out valid htree-path2654 */2655 if (restart && err == 0)2656 goto again;2657 return err;2658}2659 2660/*2661 * ext4_generic_delete_entry deletes a directory entry by merging it2662 * with the previous entry2663 */2664int ext4_generic_delete_entry(struct inode *dir,2665 struct ext4_dir_entry_2 *de_del,2666 struct buffer_head *bh,2667 void *entry_buf,2668 int buf_size,2669 int csum_size)2670{2671 struct ext4_dir_entry_2 *de, *pde;2672 unsigned int blocksize = dir->i_sb->s_blocksize;2673 int i;2674 2675 i = 0;2676 pde = NULL;2677 de = entry_buf;2678 while (i < buf_size - csum_size) {2679 if (ext4_check_dir_entry(dir, NULL, de, bh,2680 entry_buf, buf_size, i))2681 return -EFSCORRUPTED;2682 if (de == de_del) {2683 if (pde) {2684 pde->rec_len = ext4_rec_len_to_disk(2685 ext4_rec_len_from_disk(pde->rec_len,2686 blocksize) +2687 ext4_rec_len_from_disk(de->rec_len,2688 blocksize),2689 blocksize);2690 2691 /* wipe entire dir_entry */2692 memset(de, 0, ext4_rec_len_from_disk(de->rec_len,2693 blocksize));2694 } else {2695 /* wipe dir_entry excluding the rec_len field */2696 de->inode = 0;2697 memset(&de->name_len, 0,2698 ext4_rec_len_from_disk(de->rec_len,2699 blocksize) -2700 offsetof(struct ext4_dir_entry_2,2701 name_len));2702 }2703 2704 inode_inc_iversion(dir);2705 return 0;2706 }2707 i += ext4_rec_len_from_disk(de->rec_len, blocksize);2708 pde = de;2709 de = ext4_next_entry(de, blocksize);2710 }2711 return -ENOENT;2712}2713 2714static int ext4_delete_entry(handle_t *handle,2715 struct inode *dir,2716 struct ext4_dir_entry_2 *de_del,2717 struct buffer_head *bh)2718{2719 int err, csum_size = 0;2720 2721 if (ext4_has_inline_data(dir)) {2722 int has_inline_data = 1;2723 err = ext4_delete_inline_entry(handle, dir, de_del, bh,2724 &has_inline_data);2725 if (has_inline_data)2726 return err;2727 }2728 2729 if (ext4_has_metadata_csum(dir->i_sb))2730 csum_size = sizeof(struct ext4_dir_entry_tail);2731 2732 BUFFER_TRACE(bh, "get_write_access");2733 err = ext4_journal_get_write_access(handle, dir->i_sb, bh,2734 EXT4_JTR_NONE);2735 if (unlikely(err))2736 goto out;2737 2738 err = ext4_generic_delete_entry(dir, de_del, bh, bh->b_data,2739 dir->i_sb->s_blocksize, csum_size);2740 if (err)2741 goto out;2742 2743 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");2744 err = ext4_handle_dirty_dirblock(handle, dir, bh);2745 if (unlikely(err))2746 goto out;2747 2748 return 0;2749out:2750 if (err != -ENOENT)2751 ext4_std_error(dir->i_sb, err);2752 return err;2753}2754 2755/*2756 * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 22757 * since this indicates that nlinks count was previously 1 to avoid overflowing2758 * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean2759 * that subdirectory link counts are not being maintained accurately.2760 *2761 * The caller has already checked for i_nlink overflow in case the DIR_LINK2762 * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy2763 * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set2764 * on regular files) and to avoid creating huge/slow non-HTREE directories.2765 */2766static void ext4_inc_count(struct inode *inode)2767{2768 inc_nlink(inode);2769 if (is_dx(inode) &&2770 (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))2771 set_nlink(inode, 1);2772}2773 2774/*2775 * If a directory had nlink == 1, then we should let it be 1. This indicates2776 * directory has >EXT4_LINK_MAX subdirs.2777 */2778static void ext4_dec_count(struct inode *inode)2779{2780 if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)2781 drop_nlink(inode);2782}2783 2784 2785/*2786 * Add non-directory inode to a directory. On success, the inode reference is2787 * consumed by dentry is instantiation. This is also indicated by clearing of2788 * *inodep pointer. On failure, the caller is responsible for dropping the2789 * inode reference in the safe context.2790 */2791static int ext4_add_nondir(handle_t *handle,2792 struct dentry *dentry, struct inode **inodep)2793{2794 struct inode *dir = d_inode(dentry->d_parent);2795 struct inode *inode = *inodep;2796 int err = ext4_add_entry(handle, dentry, inode);2797 if (!err) {2798 err = ext4_mark_inode_dirty(handle, inode);2799 if (IS_DIRSYNC(dir))2800 ext4_handle_sync(handle);2801 d_instantiate_new(dentry, inode);2802 *inodep = NULL;2803 return err;2804 }2805 drop_nlink(inode);2806 ext4_mark_inode_dirty(handle, inode);2807 ext4_orphan_add(handle, inode);2808 unlock_new_inode(inode);2809 return err;2810}2811 2812/*2813 * By the time this is called, we already have created2814 * the directory cache entry for the new file, but it2815 * is so far negative - it has no inode.2816 *2817 * If the create succeeds, we fill in the inode information2818 * with d_instantiate().2819 */2820static int ext4_create(struct mnt_idmap *idmap, struct inode *dir,2821 struct dentry *dentry, umode_t mode, bool excl)2822{2823 handle_t *handle;2824 struct inode *inode;2825 int err, credits, retries = 0;2826 2827 err = dquot_initialize(dir);2828 if (err)2829 return err;2830 2831 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +2832 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);2833retry:2834 inode = ext4_new_inode_start_handle(idmap, dir, mode, &dentry->d_name,2835 0, NULL, EXT4_HT_DIR, credits);2836 handle = ext4_journal_current_handle();2837 err = PTR_ERR(inode);2838 if (!IS_ERR(inode)) {2839 inode->i_op = &ext4_file_inode_operations;2840 inode->i_fop = &ext4_file_operations;2841 ext4_set_aops(inode);2842 err = ext4_add_nondir(handle, dentry, &inode);2843 if (!err)2844 ext4_fc_track_create(handle, dentry);2845 }2846 if (handle)2847 ext4_journal_stop(handle);2848 if (!IS_ERR_OR_NULL(inode))2849 iput(inode);2850 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))2851 goto retry;2852 return err;2853}2854 2855static int ext4_mknod(struct mnt_idmap *idmap, struct inode *dir,2856 struct dentry *dentry, umode_t mode, dev_t rdev)2857{2858 handle_t *handle;2859 struct inode *inode;2860 int err, credits, retries = 0;2861 2862 err = dquot_initialize(dir);2863 if (err)2864 return err;2865 2866 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +2867 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);2868retry:2869 inode = ext4_new_inode_start_handle(idmap, dir, mode, &dentry->d_name,2870 0, NULL, EXT4_HT_DIR, credits);2871 handle = ext4_journal_current_handle();2872 err = PTR_ERR(inode);2873 if (!IS_ERR(inode)) {2874 init_special_inode(inode, inode->i_mode, rdev);2875 inode->i_op = &ext4_special_inode_operations;2876 err = ext4_add_nondir(handle, dentry, &inode);2877 if (!err)2878 ext4_fc_track_create(handle, dentry);2879 }2880 if (handle)2881 ext4_journal_stop(handle);2882 if (!IS_ERR_OR_NULL(inode))2883 iput(inode);2884 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))2885 goto retry;2886 return err;2887}2888 2889static int ext4_tmpfile(struct mnt_idmap *idmap, struct inode *dir,2890 struct file *file, umode_t mode)2891{2892 handle_t *handle;2893 struct inode *inode;2894 int err, retries = 0;2895 2896 err = dquot_initialize(dir);2897 if (err)2898 return err;2899 2900retry:2901 inode = ext4_new_inode_start_handle(idmap, dir, mode,2902 NULL, 0, NULL,2903 EXT4_HT_DIR,2904 EXT4_MAXQUOTAS_TRANS_BLOCKS(dir->i_sb) +2905 4 + EXT4_XATTR_TRANS_BLOCKS);2906 handle = ext4_journal_current_handle();2907 err = PTR_ERR(inode);2908 if (!IS_ERR(inode)) {2909 inode->i_op = &ext4_file_inode_operations;2910 inode->i_fop = &ext4_file_operations;2911 ext4_set_aops(inode);2912 d_tmpfile(file, inode);2913 err = ext4_orphan_add(handle, inode);2914 if (err)2915 goto err_unlock_inode;2916 mark_inode_dirty(inode);2917 unlock_new_inode(inode);2918 }2919 if (handle)2920 ext4_journal_stop(handle);2921 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))2922 goto retry;2923 return finish_open_simple(file, err);2924err_unlock_inode:2925 ext4_journal_stop(handle);2926 unlock_new_inode(inode);2927 return err;2928}2929 2930struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,2931 struct ext4_dir_entry_2 *de,2932 int blocksize, int csum_size,2933 unsigned int parent_ino, int dotdot_real_len)2934{2935 de->inode = cpu_to_le32(inode->i_ino);2936 de->name_len = 1;2937 de->rec_len = ext4_rec_len_to_disk(ext4_dir_rec_len(de->name_len, NULL),2938 blocksize);2939 strcpy(de->name, ".");2940 ext4_set_de_type(inode->i_sb, de, S_IFDIR);2941 2942 de = ext4_next_entry(de, blocksize);2943 de->inode = cpu_to_le32(parent_ino);2944 de->name_len = 2;2945 if (!dotdot_real_len)2946 de->rec_len = ext4_rec_len_to_disk(blocksize -2947 (csum_size + ext4_dir_rec_len(1, NULL)),2948 blocksize);2949 else2950 de->rec_len = ext4_rec_len_to_disk(2951 ext4_dir_rec_len(de->name_len, NULL),2952 blocksize);2953 strcpy(de->name, "..");2954 ext4_set_de_type(inode->i_sb, de, S_IFDIR);2955 2956 return ext4_next_entry(de, blocksize);2957}2958 2959int ext4_init_new_dir(handle_t *handle, struct inode *dir,2960 struct inode *inode)2961{2962 struct buffer_head *dir_block = NULL;2963 struct ext4_dir_entry_2 *de;2964 ext4_lblk_t block = 0;2965 unsigned int blocksize = dir->i_sb->s_blocksize;2966 int csum_size = 0;2967 int err;2968 2969 if (ext4_has_metadata_csum(dir->i_sb))2970 csum_size = sizeof(struct ext4_dir_entry_tail);2971 2972 if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {2973 err = ext4_try_create_inline_dir(handle, dir, inode);2974 if (err < 0 && err != -ENOSPC)2975 goto out;2976 if (!err)2977 goto out;2978 }2979 2980 inode->i_size = 0;2981 dir_block = ext4_append(handle, inode, &block);2982 if (IS_ERR(dir_block))2983 return PTR_ERR(dir_block);2984 de = (struct ext4_dir_entry_2 *)dir_block->b_data;2985 ext4_init_dot_dotdot(inode, de, blocksize, csum_size, dir->i_ino, 0);2986 set_nlink(inode, 2);2987 if (csum_size)2988 ext4_initialize_dirent_tail(dir_block, blocksize);2989 2990 BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");2991 err = ext4_handle_dirty_dirblock(handle, inode, dir_block);2992 if (err)2993 goto out;2994 set_buffer_verified(dir_block);2995out:2996 brelse(dir_block);2997 return err;2998}2999 3000static int ext4_mkdir(struct mnt_idmap *idmap, struct inode *dir,3001 struct dentry *dentry, umode_t mode)3002{3003 handle_t *handle;3004 struct inode *inode;3005 int err, err2 = 0, credits, retries = 0;3006 3007 if (EXT4_DIR_LINK_MAX(dir))3008 return -EMLINK;3009 3010 err = dquot_initialize(dir);3011 if (err)3012 return err;3013 3014 credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +3015 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);3016retry:3017 inode = ext4_new_inode_start_handle(idmap, dir, S_IFDIR | mode,3018 &dentry->d_name,3019 0, NULL, EXT4_HT_DIR, credits);3020 handle = ext4_journal_current_handle();3021 err = PTR_ERR(inode);3022 if (IS_ERR(inode))3023 goto out_stop;3024 3025 inode->i_op = &ext4_dir_inode_operations;3026 inode->i_fop = &ext4_dir_operations;3027 err = ext4_init_new_dir(handle, dir, inode);3028 if (err)3029 goto out_clear_inode;3030 err = ext4_mark_inode_dirty(handle, inode);3031 if (!err)3032 err = ext4_add_entry(handle, dentry, inode);3033 if (err) {3034out_clear_inode:3035 clear_nlink(inode);3036 ext4_orphan_add(handle, inode);3037 unlock_new_inode(inode);3038 err2 = ext4_mark_inode_dirty(handle, inode);3039 if (unlikely(err2))3040 err = err2;3041 ext4_journal_stop(handle);3042 iput(inode);3043 goto out_retry;3044 }3045 ext4_inc_count(dir);3046 3047 ext4_update_dx_flag(dir);3048 err = ext4_mark_inode_dirty(handle, dir);3049 if (err)3050 goto out_clear_inode;3051 d_instantiate_new(dentry, inode);3052 ext4_fc_track_create(handle, dentry);3053 if (IS_DIRSYNC(dir))3054 ext4_handle_sync(handle);3055 3056out_stop:3057 if (handle)3058 ext4_journal_stop(handle);3059out_retry:3060 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))3061 goto retry;3062 return err;3063}3064 3065/*3066 * routine to check that the specified directory is empty (for rmdir)3067 */3068bool ext4_empty_dir(struct inode *inode)3069{3070 unsigned int offset;3071 struct buffer_head *bh;3072 struct ext4_dir_entry_2 *de;3073 struct super_block *sb;3074 3075 if (ext4_has_inline_data(inode)) {3076 int has_inline_data = 1;3077 int ret;3078 3079 ret = empty_inline_dir(inode, &has_inline_data);3080 if (has_inline_data)3081 return ret;3082 }3083 3084 sb = inode->i_sb;3085 if (inode->i_size < ext4_dir_rec_len(1, NULL) +3086 ext4_dir_rec_len(2, NULL)) {3087 EXT4_ERROR_INODE(inode, "invalid size");3088 return false;3089 }3090 bh = ext4_read_dirblock(inode, 0, EITHER);3091 if (IS_ERR(bh))3092 return false;3093 3094 de = (struct ext4_dir_entry_2 *) bh->b_data;3095 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,3096 0) ||3097 le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) {3098 ext4_warning_inode(inode, "directory missing '.'");3099 brelse(bh);3100 return false;3101 }3102 offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);3103 de = ext4_next_entry(de, sb->s_blocksize);3104 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size,3105 offset) ||3106 le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) {3107 ext4_warning_inode(inode, "directory missing '..'");3108 brelse(bh);3109 return false;3110 }3111 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);3112 while (offset < inode->i_size) {3113 if (!(offset & (sb->s_blocksize - 1))) {3114 unsigned int lblock;3115 brelse(bh);3116 lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);3117 bh = ext4_read_dirblock(inode, lblock, EITHER);3118 if (bh == NULL) {3119 offset += sb->s_blocksize;3120 continue;3121 }3122 if (IS_ERR(bh))3123 return false;3124 }3125 de = (struct ext4_dir_entry_2 *) (bh->b_data +3126 (offset & (sb->s_blocksize - 1)));3127 if (ext4_check_dir_entry(inode, NULL, de, bh,3128 bh->b_data, bh->b_size, offset) ||3129 le32_to_cpu(de->inode)) {3130 brelse(bh);3131 return false;3132 }3133 offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);3134 }3135 brelse(bh);3136 return true;3137}3138 3139static int ext4_rmdir(struct inode *dir, struct dentry *dentry)3140{3141 int retval;3142 struct inode *inode;3143 struct buffer_head *bh;3144 struct ext4_dir_entry_2 *de;3145 handle_t *handle = NULL;3146 3147 if (unlikely(ext4_forced_shutdown(dir->i_sb)))3148 return -EIO;3149 3150 /* Initialize quotas before so that eventual writes go in3151 * separate transaction */3152 retval = dquot_initialize(dir);3153 if (retval)3154 return retval;3155 retval = dquot_initialize(d_inode(dentry));3156 if (retval)3157 return retval;3158 3159 retval = -ENOENT;3160 bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);3161 if (IS_ERR(bh))3162 return PTR_ERR(bh);3163 if (!bh)3164 goto end_rmdir;3165 3166 inode = d_inode(dentry);3167 3168 retval = -EFSCORRUPTED;3169 if (le32_to_cpu(de->inode) != inode->i_ino)3170 goto end_rmdir;3171 3172 retval = -ENOTEMPTY;3173 if (!ext4_empty_dir(inode))3174 goto end_rmdir;3175 3176 handle = ext4_journal_start(dir, EXT4_HT_DIR,3177 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));3178 if (IS_ERR(handle)) {3179 retval = PTR_ERR(handle);3180 handle = NULL;3181 goto end_rmdir;3182 }3183 3184 if (IS_DIRSYNC(dir))3185 ext4_handle_sync(handle);3186 3187 retval = ext4_delete_entry(handle, dir, de, bh);3188 if (retval)3189 goto end_rmdir;3190 if (!EXT4_DIR_LINK_EMPTY(inode))3191 ext4_warning_inode(inode,3192 "empty directory '%.*s' has too many links (%u)",3193 dentry->d_name.len, dentry->d_name.name,3194 inode->i_nlink);3195 inode_inc_iversion(inode);3196 clear_nlink(inode);3197 /* There's no need to set i_disksize: the fact that i_nlink is3198 * zero will ensure that the right thing happens during any3199 * recovery. */3200 inode->i_size = 0;3201 ext4_orphan_add(handle, inode);3202 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));3203 inode_set_ctime_current(inode);3204 retval = ext4_mark_inode_dirty(handle, inode);3205 if (retval)3206 goto end_rmdir;3207 ext4_dec_count(dir);3208 ext4_update_dx_flag(dir);3209 ext4_fc_track_unlink(handle, dentry);3210 retval = ext4_mark_inode_dirty(handle, dir);3211 3212 /* VFS negative dentries are incompatible with Encoding and3213 * Case-insensitiveness. Eventually we'll want avoid3214 * invalidating the dentries here, alongside with returning the3215 * negative dentries at ext4_lookup(), when it is better3216 * supported by the VFS for the CI case.3217 */3218 if (IS_ENABLED(CONFIG_UNICODE) && IS_CASEFOLDED(dir))3219 d_invalidate(dentry);3220 3221end_rmdir:3222 brelse(bh);3223 if (handle)3224 ext4_journal_stop(handle);3225 return retval;3226}3227 3228int __ext4_unlink(struct inode *dir, const struct qstr *d_name,3229 struct inode *inode,3230 struct dentry *dentry /* NULL during fast_commit recovery */)3231{3232 int retval = -ENOENT;3233 struct buffer_head *bh;3234 struct ext4_dir_entry_2 *de;3235 handle_t *handle;3236 int skip_remove_dentry = 0;3237 3238 /*3239 * Keep this outside the transaction; it may have to set up the3240 * directory's encryption key, which isn't GFP_NOFS-safe.3241 */3242 bh = ext4_find_entry(dir, d_name, &de, NULL);3243 if (IS_ERR(bh))3244 return PTR_ERR(bh);3245 3246 if (!bh)3247 return -ENOENT;3248 3249 if (le32_to_cpu(de->inode) != inode->i_ino) {3250 /*3251 * It's okay if we find dont find dentry which matches3252 * the inode. That's because it might have gotten3253 * renamed to a different inode number3254 */3255 if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)3256 skip_remove_dentry = 1;3257 else3258 goto out_bh;3259 }3260 3261 handle = ext4_journal_start(dir, EXT4_HT_DIR,3262 EXT4_DATA_TRANS_BLOCKS(dir->i_sb));3263 if (IS_ERR(handle)) {3264 retval = PTR_ERR(handle);3265 goto out_bh;3266 }3267 3268 if (IS_DIRSYNC(dir))3269 ext4_handle_sync(handle);3270 3271 if (!skip_remove_dentry) {3272 retval = ext4_delete_entry(handle, dir, de, bh);3273 if (retval)3274 goto out_handle;3275 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));3276 ext4_update_dx_flag(dir);3277 retval = ext4_mark_inode_dirty(handle, dir);3278 if (retval)3279 goto out_handle;3280 } else {3281 retval = 0;3282 }3283 if (inode->i_nlink == 0)3284 ext4_warning_inode(inode, "Deleting file '%.*s' with no links",3285 d_name->len, d_name->name);3286 else3287 drop_nlink(inode);3288 if (!inode->i_nlink)3289 ext4_orphan_add(handle, inode);3290 inode_set_ctime_current(inode);3291 retval = ext4_mark_inode_dirty(handle, inode);3292 if (dentry && !retval)3293 ext4_fc_track_unlink(handle, dentry);3294out_handle:3295 ext4_journal_stop(handle);3296out_bh:3297 brelse(bh);3298 return retval;3299}3300 3301static int ext4_unlink(struct inode *dir, struct dentry *dentry)3302{3303 int retval;3304 3305 if (unlikely(ext4_forced_shutdown(dir->i_sb)))3306 return -EIO;3307 3308 trace_ext4_unlink_enter(dir, dentry);3309 /*3310 * Initialize quotas before so that eventual writes go3311 * in separate transaction3312 */3313 retval = dquot_initialize(dir);3314 if (retval)3315 goto out_trace;3316 retval = dquot_initialize(d_inode(dentry));3317 if (retval)3318 goto out_trace;3319 3320 retval = __ext4_unlink(dir, &dentry->d_name, d_inode(dentry), dentry);3321 3322 /* VFS negative dentries are incompatible with Encoding and3323 * Case-insensitiveness. Eventually we'll want avoid3324 * invalidating the dentries here, alongside with returning the3325 * negative dentries at ext4_lookup(), when it is better3326 * supported by the VFS for the CI case.3327 */3328 if (IS_ENABLED(CONFIG_UNICODE) && IS_CASEFOLDED(dir))3329 d_invalidate(dentry);3330 3331out_trace:3332 trace_ext4_unlink_exit(dentry, retval);3333 return retval;3334}3335 3336static int ext4_init_symlink_block(handle_t *handle, struct inode *inode,3337 struct fscrypt_str *disk_link)3338{3339 struct buffer_head *bh;3340 char *kaddr;3341 int err = 0;3342 3343 bh = ext4_bread(handle, inode, 0, EXT4_GET_BLOCKS_CREATE);3344 if (IS_ERR(bh))3345 return PTR_ERR(bh);3346 3347 BUFFER_TRACE(bh, "get_write_access");3348 err = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE);3349 if (err)3350 goto out;3351 3352 kaddr = (char *)bh->b_data;3353 memcpy(kaddr, disk_link->name, disk_link->len);3354 inode->i_size = disk_link->len - 1;3355 EXT4_I(inode)->i_disksize = inode->i_size;3356 err = ext4_handle_dirty_metadata(handle, inode, bh);3357out:3358 brelse(bh);3359 return err;3360}3361 3362static int ext4_symlink(struct mnt_idmap *idmap, struct inode *dir,3363 struct dentry *dentry, const char *symname)3364{3365 handle_t *handle;3366 struct inode *inode;3367 int err, len = strlen(symname);3368 int credits;3369 struct fscrypt_str disk_link;3370 int retries = 0;3371 3372 if (unlikely(ext4_forced_shutdown(dir->i_sb)))3373 return -EIO;3374 3375 err = fscrypt_prepare_symlink(dir, symname, len, dir->i_sb->s_blocksize,3376 &disk_link);3377 if (err)3378 return err;3379 3380 err = dquot_initialize(dir);3381 if (err)3382 return err;3383 3384 /*3385 * EXT4_INDEX_EXTRA_TRANS_BLOCKS for addition of entry into the3386 * directory. +3 for inode, inode bitmap, group descriptor allocation.3387 * EXT4_DATA_TRANS_BLOCKS for the data block allocation and3388 * modification.3389 */3390 credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +3391 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;3392retry:3393 inode = ext4_new_inode_start_handle(idmap, dir, S_IFLNK|S_IRWXUGO,3394 &dentry->d_name, 0, NULL,3395 EXT4_HT_DIR, credits);3396 handle = ext4_journal_current_handle();3397 if (IS_ERR(inode)) {3398 if (handle)3399 ext4_journal_stop(handle);3400 err = PTR_ERR(inode);3401 goto out_retry;3402 }3403 3404 if (IS_ENCRYPTED(inode)) {3405 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);3406 if (err)3407 goto err_drop_inode;3408 inode->i_op = &ext4_encrypted_symlink_inode_operations;3409 } else {3410 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {3411 inode->i_op = &ext4_symlink_inode_operations;3412 } else {3413 inode->i_op = &ext4_fast_symlink_inode_operations;3414 inode->i_link = (char *)&EXT4_I(inode)->i_data;3415 }3416 }3417 3418 if ((disk_link.len > EXT4_N_BLOCKS * 4)) {3419 /* alloc symlink block and fill it */3420 err = ext4_init_symlink_block(handle, inode, &disk_link);3421 if (err)3422 goto err_drop_inode;3423 } else {3424 /* clear the extent format for fast symlink */3425 ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);3426 memcpy((char *)&EXT4_I(inode)->i_data, disk_link.name,3427 disk_link.len);3428 inode->i_size = disk_link.len - 1;3429 EXT4_I(inode)->i_disksize = inode->i_size;3430 }3431 err = ext4_add_nondir(handle, dentry, &inode);3432 if (handle)3433 ext4_journal_stop(handle);3434 iput(inode);3435 goto out_retry;3436 3437err_drop_inode:3438 clear_nlink(inode);3439 ext4_mark_inode_dirty(handle, inode);3440 ext4_orphan_add(handle, inode);3441 unlock_new_inode(inode);3442 if (handle)3443 ext4_journal_stop(handle);3444 iput(inode);3445out_retry:3446 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))3447 goto retry;3448 if (disk_link.name != (unsigned char *)symname)3449 kfree(disk_link.name);3450 return err;3451}3452 3453int __ext4_link(struct inode *dir, struct inode *inode, struct dentry *dentry)3454{3455 handle_t *handle;3456 int err, retries = 0;3457retry:3458 handle = ext4_journal_start(dir, EXT4_HT_DIR,3459 (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +3460 EXT4_INDEX_EXTRA_TRANS_BLOCKS) + 1);3461 if (IS_ERR(handle))3462 return PTR_ERR(handle);3463 3464 if (IS_DIRSYNC(dir))3465 ext4_handle_sync(handle);3466 3467 inode_set_ctime_current(inode);3468 ext4_inc_count(inode);3469 ihold(inode);3470 3471 err = ext4_add_entry(handle, dentry, inode);3472 if (!err) {3473 err = ext4_mark_inode_dirty(handle, inode);3474 /* this can happen only for tmpfile being3475 * linked the first time3476 */3477 if (inode->i_nlink == 1)3478 ext4_orphan_del(handle, inode);3479 d_instantiate(dentry, inode);3480 ext4_fc_track_link(handle, dentry);3481 } else {3482 drop_nlink(inode);3483 iput(inode);3484 }3485 ext4_journal_stop(handle);3486 if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))3487 goto retry;3488 return err;3489}3490 3491static int ext4_link(struct dentry *old_dentry,3492 struct inode *dir, struct dentry *dentry)3493{3494 struct inode *inode = d_inode(old_dentry);3495 int err;3496 3497 if (inode->i_nlink >= EXT4_LINK_MAX)3498 return -EMLINK;3499 3500 err = fscrypt_prepare_link(old_dentry, dir, dentry);3501 if (err)3502 return err;3503 3504 if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&3505 (!projid_eq(EXT4_I(dir)->i_projid,3506 EXT4_I(old_dentry->d_inode)->i_projid)))3507 return -EXDEV;3508 3509 err = dquot_initialize(dir);3510 if (err)3511 return err;3512 return __ext4_link(dir, inode, dentry);3513}3514 3515/*3516 * Try to find buffer head where contains the parent block.3517 * It should be the inode block if it is inlined or the 1st block3518 * if it is a normal dir.3519 */3520static struct buffer_head *ext4_get_first_dir_block(handle_t *handle,3521 struct inode *inode,3522 int *retval,3523 struct ext4_dir_entry_2 **parent_de,3524 int *inlined)3525{3526 struct buffer_head *bh;3527 3528 if (!ext4_has_inline_data(inode)) {3529 struct ext4_dir_entry_2 *de;3530 unsigned int offset;3531 3532 bh = ext4_read_dirblock(inode, 0, EITHER);3533 if (IS_ERR(bh)) {3534 *retval = PTR_ERR(bh);3535 return NULL;3536 }3537 3538 de = (struct ext4_dir_entry_2 *) bh->b_data;3539 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data,3540 bh->b_size, 0) ||3541 le32_to_cpu(de->inode) != inode->i_ino ||3542 strcmp(".", de->name)) {3543 EXT4_ERROR_INODE(inode, "directory missing '.'");3544 brelse(bh);3545 *retval = -EFSCORRUPTED;3546 return NULL;3547 }3548 offset = ext4_rec_len_from_disk(de->rec_len,3549 inode->i_sb->s_blocksize);3550 de = ext4_next_entry(de, inode->i_sb->s_blocksize);3551 if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data,3552 bh->b_size, offset) ||3553 le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) {3554 EXT4_ERROR_INODE(inode, "directory missing '..'");3555 brelse(bh);3556 *retval = -EFSCORRUPTED;3557 return NULL;3558 }3559 *parent_de = de;3560 3561 return bh;3562 }3563 3564 *inlined = 1;3565 return ext4_get_first_inline_block(inode, parent_de, retval);3566}3567 3568struct ext4_renament {3569 struct inode *dir;3570 struct dentry *dentry;3571 struct inode *inode;3572 bool is_dir;3573 int dir_nlink_delta;3574 3575 /* entry for "dentry" */3576 struct buffer_head *bh;3577 struct ext4_dir_entry_2 *de;3578 int inlined;3579 3580 /* entry for ".." in inode if it's a directory */3581 struct buffer_head *dir_bh;3582 struct ext4_dir_entry_2 *parent_de;3583 int dir_inlined;3584};3585 3586static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent, bool is_cross)3587{3588 int retval;3589 3590 ent->is_dir = true;3591 if (!is_cross)3592 return 0;3593 3594 ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,3595 &retval, &ent->parent_de,3596 &ent->dir_inlined);3597 if (!ent->dir_bh)3598 return retval;3599 if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)3600 return -EFSCORRUPTED;3601 BUFFER_TRACE(ent->dir_bh, "get_write_access");3602 return ext4_journal_get_write_access(handle, ent->dir->i_sb,3603 ent->dir_bh, EXT4_JTR_NONE);3604}3605 3606static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,3607 unsigned dir_ino)3608{3609 int retval;3610 3611 if (!ent->dir_bh)3612 return 0;3613 3614 ent->parent_de->inode = cpu_to_le32(dir_ino);3615 BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");3616 if (!ent->dir_inlined) {3617 if (is_dx(ent->inode)) {3618 retval = ext4_handle_dirty_dx_node(handle,3619 ent->inode,3620 ent->dir_bh);3621 } else {3622 retval = ext4_handle_dirty_dirblock(handle, ent->inode,3623 ent->dir_bh);3624 }3625 } else {3626 retval = ext4_mark_inode_dirty(handle, ent->inode);3627 }3628 if (retval) {3629 ext4_std_error(ent->dir->i_sb, retval);3630 return retval;3631 }3632 return 0;3633}3634 3635static int ext4_setent(handle_t *handle, struct ext4_renament *ent,3636 unsigned ino, unsigned file_type)3637{3638 int retval, retval2;3639 3640 BUFFER_TRACE(ent->bh, "get write access");3641 retval = ext4_journal_get_write_access(handle, ent->dir->i_sb, ent->bh,3642 EXT4_JTR_NONE);3643 if (retval)3644 return retval;3645 ent->de->inode = cpu_to_le32(ino);3646 if (ext4_has_feature_filetype(ent->dir->i_sb))3647 ent->de->file_type = file_type;3648 inode_inc_iversion(ent->dir);3649 inode_set_mtime_to_ts(ent->dir, inode_set_ctime_current(ent->dir));3650 retval = ext4_mark_inode_dirty(handle, ent->dir);3651 BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");3652 if (!ent->inlined) {3653 retval2 = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh);3654 if (unlikely(retval2)) {3655 ext4_std_error(ent->dir->i_sb, retval2);3656 return retval2;3657 }3658 }3659 return retval;3660}3661 3662static void ext4_resetent(handle_t *handle, struct ext4_renament *ent,3663 unsigned ino, unsigned file_type)3664{3665 struct ext4_renament old = *ent;3666 int retval = 0;3667 3668 /*3669 * old->de could have moved from under us during make indexed dir,3670 * so the old->de may no longer valid and need to find it again3671 * before reset old inode info.3672 */3673 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de,3674 &old.inlined);3675 if (IS_ERR(old.bh))3676 retval = PTR_ERR(old.bh);3677 if (!old.bh)3678 retval = -ENOENT;3679 if (retval) {3680 ext4_std_error(old.dir->i_sb, retval);3681 return;3682 }3683 3684 ext4_setent(handle, &old, ino, file_type);3685 brelse(old.bh);3686}3687 3688static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,3689 const struct qstr *d_name)3690{3691 int retval = -ENOENT;3692 struct buffer_head *bh;3693 struct ext4_dir_entry_2 *de;3694 3695 bh = ext4_find_entry(dir, d_name, &de, NULL);3696 if (IS_ERR(bh))3697 return PTR_ERR(bh);3698 if (bh) {3699 retval = ext4_delete_entry(handle, dir, de, bh);3700 brelse(bh);3701 }3702 return retval;3703}3704 3705static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent,3706 int force_reread)3707{3708 int retval;3709 /*3710 * ent->de could have moved from under us during htree split, so make3711 * sure that we are deleting the right entry. We might also be pointing3712 * to a stale entry in the unused part of ent->bh so just checking inum3713 * and the name isn't enough.3714 */3715 if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||3716 ent->de->name_len != ent->dentry->d_name.len ||3717 strncmp(ent->de->name, ent->dentry->d_name.name,3718 ent->de->name_len) ||3719 force_reread) {3720 retval = ext4_find_delete_entry(handle, ent->dir,3721 &ent->dentry->d_name);3722 } else {3723 retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);3724 if (retval == -ENOENT) {3725 retval = ext4_find_delete_entry(handle, ent->dir,3726 &ent->dentry->d_name);3727 }3728 }3729 3730 if (retval) {3731 ext4_warning_inode(ent->dir,3732 "Deleting old file: nlink %d, error=%d",3733 ent->dir->i_nlink, retval);3734 }3735}3736 3737static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)3738{3739 if (ent->dir_nlink_delta) {3740 if (ent->dir_nlink_delta == -1)3741 ext4_dec_count(ent->dir);3742 else3743 ext4_inc_count(ent->dir);3744 ext4_mark_inode_dirty(handle, ent->dir);3745 }3746}3747 3748static struct inode *ext4_whiteout_for_rename(struct mnt_idmap *idmap,3749 struct ext4_renament *ent,3750 int credits, handle_t **h)3751{3752 struct inode *wh;3753 handle_t *handle;3754 int retries = 0;3755 3756 /*3757 * for inode block, sb block, group summaries,3758 * and inode bitmap3759 */3760 credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +3761 EXT4_XATTR_TRANS_BLOCKS + 4);3762retry:3763 wh = ext4_new_inode_start_handle(idmap, ent->dir,3764 S_IFCHR | WHITEOUT_MODE,3765 &ent->dentry->d_name, 0, NULL,3766 EXT4_HT_DIR, credits);3767 3768 handle = ext4_journal_current_handle();3769 if (IS_ERR(wh)) {3770 if (handle)3771 ext4_journal_stop(handle);3772 if (PTR_ERR(wh) == -ENOSPC &&3773 ext4_should_retry_alloc(ent->dir->i_sb, &retries))3774 goto retry;3775 } else {3776 *h = handle;3777 init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);3778 wh->i_op = &ext4_special_inode_operations;3779 }3780 return wh;3781}3782 3783/*3784 * Anybody can rename anything with this: the permission checks are left to the3785 * higher-level routines.3786 *3787 * n.b. old_{dentry,inode) refers to the source dentry/inode3788 * while new_{dentry,inode) refers to the destination dentry/inode3789 * This comes from rename(const char *oldpath, const char *newpath)3790 */3791static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir,3792 struct dentry *old_dentry, struct inode *new_dir,3793 struct dentry *new_dentry, unsigned int flags)3794{3795 handle_t *handle = NULL;3796 struct ext4_renament old = {3797 .dir = old_dir,3798 .dentry = old_dentry,3799 .inode = d_inode(old_dentry),3800 };3801 struct ext4_renament new = {3802 .dir = new_dir,3803 .dentry = new_dentry,3804 .inode = d_inode(new_dentry),3805 };3806 int force_reread;3807 int retval;3808 struct inode *whiteout = NULL;3809 int credits;3810 u8 old_file_type;3811 3812 if (new.inode && new.inode->i_nlink == 0) {3813 EXT4_ERROR_INODE(new.inode,3814 "target of rename is already freed");3815 return -EFSCORRUPTED;3816 }3817 3818 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT)) &&3819 (!projid_eq(EXT4_I(new_dir)->i_projid,3820 EXT4_I(old_dentry->d_inode)->i_projid)))3821 return -EXDEV;3822 3823 retval = dquot_initialize(old.dir);3824 if (retval)3825 return retval;3826 retval = dquot_initialize(old.inode);3827 if (retval)3828 return retval;3829 retval = dquot_initialize(new.dir);3830 if (retval)3831 return retval;3832 3833 /* Initialize quotas before so that eventual writes go3834 * in separate transaction */3835 if (new.inode) {3836 retval = dquot_initialize(new.inode);3837 if (retval)3838 return retval;3839 }3840 3841 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de,3842 &old.inlined);3843 if (IS_ERR(old.bh))3844 return PTR_ERR(old.bh);3845 3846 /*3847 * Check for inode number is _not_ due to possible IO errors.3848 * We might rmdir the source, keep it as pwd of some process3849 * and merrily kill the link to whatever was created under the3850 * same name. Goodbye sticky bit ;-<3851 */3852 retval = -ENOENT;3853 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)3854 goto release_bh;3855 3856 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,3857 &new.de, &new.inlined);3858 if (IS_ERR(new.bh)) {3859 retval = PTR_ERR(new.bh);3860 new.bh = NULL;3861 goto release_bh;3862 }3863 if (new.bh) {3864 if (!new.inode) {3865 brelse(new.bh);3866 new.bh = NULL;3867 }3868 }3869 if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))3870 ext4_alloc_da_blocks(old.inode);3871 3872 credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +3873 EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);3874 if (!(flags & RENAME_WHITEOUT)) {3875 handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);3876 if (IS_ERR(handle)) {3877 retval = PTR_ERR(handle);3878 goto release_bh;3879 }3880 } else {3881 whiteout = ext4_whiteout_for_rename(idmap, &old, credits, &handle);3882 if (IS_ERR(whiteout)) {3883 retval = PTR_ERR(whiteout);3884 goto release_bh;3885 }3886 }3887 3888 old_file_type = old.de->file_type;3889 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))3890 ext4_handle_sync(handle);3891 3892 if (S_ISDIR(old.inode->i_mode)) {3893 if (new.inode) {3894 retval = -ENOTEMPTY;3895 if (!ext4_empty_dir(new.inode))3896 goto end_rename;3897 } else {3898 retval = -EMLINK;3899 if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))3900 goto end_rename;3901 }3902 retval = ext4_rename_dir_prepare(handle, &old, new.dir != old.dir);3903 if (retval)3904 goto end_rename;3905 }3906 /*3907 * If we're renaming a file within an inline_data dir and adding or3908 * setting the new dirent causes a conversion from inline_data to3909 * extents/blockmap, we need to force the dirent delete code to3910 * re-read the directory, or else we end up trying to delete a dirent3911 * from what is now the extent tree root (or a block map).3912 */3913 force_reread = (new.dir->i_ino == old.dir->i_ino &&3914 ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));3915 3916 if (whiteout) {3917 /*3918 * Do this before adding a new entry, so the old entry is sure3919 * to be still pointing to the valid old entry.3920 */3921 retval = ext4_setent(handle, &old, whiteout->i_ino,3922 EXT4_FT_CHRDEV);3923 if (retval)3924 goto end_rename;3925 retval = ext4_mark_inode_dirty(handle, whiteout);3926 if (unlikely(retval))3927 goto end_rename;3928 3929 }3930 if (!new.bh) {3931 retval = ext4_add_entry(handle, new.dentry, old.inode);3932 if (retval)3933 goto end_rename;3934 } else {3935 retval = ext4_setent(handle, &new,3936 old.inode->i_ino, old_file_type);3937 if (retval)3938 goto end_rename;3939 }3940 if (force_reread)3941 force_reread = !ext4_test_inode_flag(new.dir,3942 EXT4_INODE_INLINE_DATA);3943 3944 /*3945 * Like most other Unix systems, set the ctime for inodes on a3946 * rename.3947 */3948 inode_set_ctime_current(old.inode);3949 retval = ext4_mark_inode_dirty(handle, old.inode);3950 if (unlikely(retval))3951 goto end_rename;3952 3953 if (!whiteout) {3954 /*3955 * ok, that's it3956 */3957 ext4_rename_delete(handle, &old, force_reread);3958 }3959 3960 if (new.inode) {3961 ext4_dec_count(new.inode);3962 inode_set_ctime_current(new.inode);3963 }3964 inode_set_mtime_to_ts(old.dir, inode_set_ctime_current(old.dir));3965 ext4_update_dx_flag(old.dir);3966 if (old.is_dir) {3967 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);3968 if (retval)3969 goto end_rename;3970 3971 ext4_dec_count(old.dir);3972 if (new.inode) {3973 /* checked ext4_empty_dir above, can't have another3974 * parent, ext4_dec_count() won't work for many-linked3975 * dirs */3976 clear_nlink(new.inode);3977 } else {3978 ext4_inc_count(new.dir);3979 ext4_update_dx_flag(new.dir);3980 retval = ext4_mark_inode_dirty(handle, new.dir);3981 if (unlikely(retval))3982 goto end_rename;3983 }3984 }3985 retval = ext4_mark_inode_dirty(handle, old.dir);3986 if (unlikely(retval))3987 goto end_rename;3988 3989 if (old.is_dir) {3990 /*3991 * We disable fast commits here that's because the3992 * replay code is not yet capable of changing dot dot3993 * dirents in directories.3994 */3995 ext4_fc_mark_ineligible(old.inode->i_sb,3996 EXT4_FC_REASON_RENAME_DIR, handle);3997 } else {3998 struct super_block *sb = old.inode->i_sb;3999 4000 if (new.inode)4001 ext4_fc_track_unlink(handle, new.dentry);4002 if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&4003 !(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY) &&4004 !(ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE))) {4005 __ext4_fc_track_link(handle, old.inode, new.dentry);4006 __ext4_fc_track_unlink(handle, old.inode, old.dentry);4007 if (whiteout)4008 __ext4_fc_track_create(handle, whiteout,4009 old.dentry);4010 }4011 }4012 4013 if (new.inode) {4014 retval = ext4_mark_inode_dirty(handle, new.inode);4015 if (unlikely(retval))4016 goto end_rename;4017 if (!new.inode->i_nlink)4018 ext4_orphan_add(handle, new.inode);4019 }4020 retval = 0;4021 4022end_rename:4023 if (whiteout) {4024 if (retval) {4025 ext4_resetent(handle, &old,4026 old.inode->i_ino, old_file_type);4027 drop_nlink(whiteout);4028 ext4_mark_inode_dirty(handle, whiteout);4029 ext4_orphan_add(handle, whiteout);4030 }4031 unlock_new_inode(whiteout);4032 ext4_journal_stop(handle);4033 iput(whiteout);4034 } else {4035 ext4_journal_stop(handle);4036 }4037release_bh:4038 brelse(old.dir_bh);4039 brelse(old.bh);4040 brelse(new.bh);4041 4042 return retval;4043}4044 4045static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,4046 struct inode *new_dir, struct dentry *new_dentry)4047{4048 handle_t *handle = NULL;4049 struct ext4_renament old = {4050 .dir = old_dir,4051 .dentry = old_dentry,4052 .inode = d_inode(old_dentry),4053 };4054 struct ext4_renament new = {4055 .dir = new_dir,4056 .dentry = new_dentry,4057 .inode = d_inode(new_dentry),4058 };4059 u8 new_file_type;4060 int retval;4061 4062 if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&4063 !projid_eq(EXT4_I(new_dir)->i_projid,4064 EXT4_I(old_dentry->d_inode)->i_projid)) ||4065 (ext4_test_inode_flag(old_dir, EXT4_INODE_PROJINHERIT) &&4066 !projid_eq(EXT4_I(old_dir)->i_projid,4067 EXT4_I(new_dentry->d_inode)->i_projid)))4068 return -EXDEV;4069 4070 retval = dquot_initialize(old.dir);4071 if (retval)4072 return retval;4073 retval = dquot_initialize(new.dir);4074 if (retval)4075 return retval;4076 4077 old.bh = ext4_find_entry(old.dir, &old.dentry->d_name,4078 &old.de, &old.inlined);4079 if (IS_ERR(old.bh))4080 return PTR_ERR(old.bh);4081 /*4082 * Check for inode number is _not_ due to possible IO errors.4083 * We might rmdir the source, keep it as pwd of some process4084 * and merrily kill the link to whatever was created under the4085 * same name. Goodbye sticky bit ;-<4086 */4087 retval = -ENOENT;4088 if (!old.bh || le32_to_cpu(old.de->inode) != old.inode->i_ino)4089 goto end_rename;4090 4091 new.bh = ext4_find_entry(new.dir, &new.dentry->d_name,4092 &new.de, &new.inlined);4093 if (IS_ERR(new.bh)) {4094 retval = PTR_ERR(new.bh);4095 new.bh = NULL;4096 goto end_rename;4097 }4098 4099 /* RENAME_EXCHANGE case: old *and* new must both exist */4100 if (!new.bh || le32_to_cpu(new.de->inode) != new.inode->i_ino)4101 goto end_rename;4102 4103 handle = ext4_journal_start(old.dir, EXT4_HT_DIR,4104 (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +4105 2 * EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));4106 if (IS_ERR(handle)) {4107 retval = PTR_ERR(handle);4108 handle = NULL;4109 goto end_rename;4110 }4111 4112 if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))4113 ext4_handle_sync(handle);4114 4115 if (S_ISDIR(old.inode->i_mode)) {4116 retval = ext4_rename_dir_prepare(handle, &old, new.dir != old.dir);4117 if (retval)4118 goto end_rename;4119 }4120 if (S_ISDIR(new.inode->i_mode)) {4121 retval = ext4_rename_dir_prepare(handle, &new, new.dir != old.dir);4122 if (retval)4123 goto end_rename;4124 }4125 4126 /*4127 * Other than the special case of overwriting a directory, parents'4128 * nlink only needs to be modified if this is a cross directory rename.4129 */4130 if (old.dir != new.dir && old.is_dir != new.is_dir) {4131 old.dir_nlink_delta = old.is_dir ? -1 : 1;4132 new.dir_nlink_delta = -old.dir_nlink_delta;4133 retval = -EMLINK;4134 if ((old.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(old.dir)) ||4135 (new.dir_nlink_delta > 0 && EXT4_DIR_LINK_MAX(new.dir)))4136 goto end_rename;4137 }4138 4139 new_file_type = new.de->file_type;4140 retval = ext4_setent(handle, &new, old.inode->i_ino, old.de->file_type);4141 if (retval)4142 goto end_rename;4143 4144 retval = ext4_setent(handle, &old, new.inode->i_ino, new_file_type);4145 if (retval)4146 goto end_rename;4147 4148 /*4149 * Like most other Unix systems, set the ctime for inodes on a4150 * rename.4151 */4152 inode_set_ctime_current(old.inode);4153 inode_set_ctime_current(new.inode);4154 retval = ext4_mark_inode_dirty(handle, old.inode);4155 if (unlikely(retval))4156 goto end_rename;4157 retval = ext4_mark_inode_dirty(handle, new.inode);4158 if (unlikely(retval))4159 goto end_rename;4160 ext4_fc_mark_ineligible(new.inode->i_sb,4161 EXT4_FC_REASON_CROSS_RENAME, handle);4162 if (old.dir_bh) {4163 retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);4164 if (retval)4165 goto end_rename;4166 }4167 if (new.dir_bh) {4168 retval = ext4_rename_dir_finish(handle, &new, old.dir->i_ino);4169 if (retval)4170 goto end_rename;4171 }4172 ext4_update_dir_count(handle, &old);4173 ext4_update_dir_count(handle, &new);4174 retval = 0;4175 4176end_rename:4177 brelse(old.dir_bh);4178 brelse(new.dir_bh);4179 brelse(old.bh);4180 brelse(new.bh);4181 if (handle)4182 ext4_journal_stop(handle);4183 return retval;4184}4185 4186static int ext4_rename2(struct mnt_idmap *idmap,4187 struct inode *old_dir, struct dentry *old_dentry,4188 struct inode *new_dir, struct dentry *new_dentry,4189 unsigned int flags)4190{4191 int err;4192 4193 if (unlikely(ext4_forced_shutdown(old_dir->i_sb)))4194 return -EIO;4195 4196 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))4197 return -EINVAL;4198 4199 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,4200 flags);4201 if (err)4202 return err;4203 4204 if (flags & RENAME_EXCHANGE) {4205 return ext4_cross_rename(old_dir, old_dentry,4206 new_dir, new_dentry);4207 }4208 4209 return ext4_rename(idmap, old_dir, old_dentry, new_dir, new_dentry, flags);4210}4211 4212/*4213 * directories can handle most operations...4214 */4215const struct inode_operations ext4_dir_inode_operations = {4216 .create = ext4_create,4217 .lookup = ext4_lookup,4218 .link = ext4_link,4219 .unlink = ext4_unlink,4220 .symlink = ext4_symlink,4221 .mkdir = ext4_mkdir,4222 .rmdir = ext4_rmdir,4223 .mknod = ext4_mknod,4224 .tmpfile = ext4_tmpfile,4225 .rename = ext4_rename2,4226 .setattr = ext4_setattr,4227 .getattr = ext4_getattr,4228 .listxattr = ext4_listxattr,4229 .get_inode_acl = ext4_get_acl,4230 .set_acl = ext4_set_acl,4231 .fiemap = ext4_fiemap,4232 .fileattr_get = ext4_fileattr_get,4233 .fileattr_set = ext4_fileattr_set,4234};4235 4236const struct inode_operations ext4_special_inode_operations = {4237 .setattr = ext4_setattr,4238 .getattr = ext4_getattr,4239 .listxattr = ext4_listxattr,4240 .get_inode_acl = ext4_get_acl,4241 .set_acl = ext4_set_acl,4242};4243