linux-stable/fs/f2fs/dir.c
Eric Biggers b5639bb431 f2fs: don't use casefolded comparison for "." and ".."
Tryng to rename a directory that has all following properties fails with
EINVAL and triggers the 'WARN_ON_ONCE(!fscrypt_has_encryption_key(dir))'
in f2fs_match_ci_name():

    - The directory is casefolded
    - The directory is encrypted
    - The directory's encryption key is not yet set up
    - The parent directory is *not* encrypted

The problem is incorrect handling of the lookup of ".." to get the
parent reference to update.  fscrypt_setup_filename() treats ".." (and
".") specially, as it's never encrypted.  It's passed through as-is, and
setting up the directory's key is not attempted.  As the name isn't a
no-key name, f2fs treats it as a "normal" name and attempts a casefolded
comparison.  That breaks the assumption of the WARN_ON_ONCE() in
f2fs_match_ci_name() which assumes that for encrypted directories,
casefolded comparisons only happen when the directory's key is set up.

We could just remove this WARN_ON_ONCE().  However, since casefolding is
always a no-op on "." and ".." anyway, let's instead just not casefold
these names.  This results in the standard bytewise comparison.

Fixes: 7ad08a58bf ("f2fs: Handle casefolding with Encryption")
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2022-05-17 11:19:23 -07:00

1160 lines
29 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* fs/f2fs/dir.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*/
#include <asm/unaligned.h>
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/sched/signal.h>
#include <linux/unicode.h>
#include "f2fs.h"
#include "node.h"
#include "acl.h"
#include "xattr.h"
#include <trace/events/f2fs.h>
#if IS_ENABLED(CONFIG_UNICODE)
extern struct kmem_cache *f2fs_cf_name_slab;
#endif
static unsigned long dir_blocks(struct inode *inode)
{
return ((unsigned long long) (i_size_read(inode) + PAGE_SIZE - 1))
>> PAGE_SHIFT;
}
static unsigned int dir_buckets(unsigned int level, int dir_level)
{
if (level + dir_level < MAX_DIR_HASH_DEPTH / 2)
return 1 << (level + dir_level);
else
return MAX_DIR_BUCKETS;
}
static unsigned int bucket_blocks(unsigned int level)
{
if (level < MAX_DIR_HASH_DEPTH / 2)
return 2;
else
return 4;
}
static unsigned char f2fs_filetype_table[F2FS_FT_MAX] = {
[F2FS_FT_UNKNOWN] = DT_UNKNOWN,
[F2FS_FT_REG_FILE] = DT_REG,
[F2FS_FT_DIR] = DT_DIR,
[F2FS_FT_CHRDEV] = DT_CHR,
[F2FS_FT_BLKDEV] = DT_BLK,
[F2FS_FT_FIFO] = DT_FIFO,
[F2FS_FT_SOCK] = DT_SOCK,
[F2FS_FT_SYMLINK] = DT_LNK,
};
static unsigned char f2fs_type_by_mode[S_IFMT >> S_SHIFT] = {
[S_IFREG >> S_SHIFT] = F2FS_FT_REG_FILE,
[S_IFDIR >> S_SHIFT] = F2FS_FT_DIR,
[S_IFCHR >> S_SHIFT] = F2FS_FT_CHRDEV,
[S_IFBLK >> S_SHIFT] = F2FS_FT_BLKDEV,
[S_IFIFO >> S_SHIFT] = F2FS_FT_FIFO,
[S_IFSOCK >> S_SHIFT] = F2FS_FT_SOCK,
[S_IFLNK >> S_SHIFT] = F2FS_FT_SYMLINK,
};
static void set_de_type(struct f2fs_dir_entry *de, umode_t mode)
{
de->file_type = f2fs_type_by_mode[(mode & S_IFMT) >> S_SHIFT];
}
unsigned char f2fs_get_de_type(struct f2fs_dir_entry *de)
{
if (de->file_type < F2FS_FT_MAX)
return f2fs_filetype_table[de->file_type];
return DT_UNKNOWN;
}
/* If @dir is casefolded, initialize @fname->cf_name from @fname->usr_fname. */
int f2fs_init_casefolded_name(const struct inode *dir,
struct f2fs_filename *fname)
{
#if IS_ENABLED(CONFIG_UNICODE)
struct super_block *sb = dir->i_sb;
if (IS_CASEFOLDED(dir) &&
!is_dot_dotdot(fname->usr_fname->name, fname->usr_fname->len)) {
fname->cf_name.name = f2fs_kmem_cache_alloc(f2fs_cf_name_slab,
GFP_NOFS, false, F2FS_SB(sb));
if (!fname->cf_name.name)
return -ENOMEM;
fname->cf_name.len = utf8_casefold(sb->s_encoding,
fname->usr_fname,
fname->cf_name.name,
F2FS_NAME_LEN);
if ((int)fname->cf_name.len <= 0) {
kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
fname->cf_name.name = NULL;
if (sb_has_strict_encoding(sb))
return -EINVAL;
/* fall back to treating name as opaque byte sequence */
}
}
#endif
return 0;
}
static int __f2fs_setup_filename(const struct inode *dir,
const struct fscrypt_name *crypt_name,
struct f2fs_filename *fname)
{
int err;
memset(fname, 0, sizeof(*fname));
fname->usr_fname = crypt_name->usr_fname;
fname->disk_name = crypt_name->disk_name;
#ifdef CONFIG_FS_ENCRYPTION
fname->crypto_buf = crypt_name->crypto_buf;
#endif
if (crypt_name->is_nokey_name) {
/* hash was decoded from the no-key name */
fname->hash = cpu_to_le32(crypt_name->hash);
} else {
err = f2fs_init_casefolded_name(dir, fname);
if (err) {
f2fs_free_filename(fname);
return err;
}
f2fs_hash_filename(dir, fname);
}
return 0;
}
/*
* Prepare to search for @iname in @dir. This is similar to
* fscrypt_setup_filename(), but this also handles computing the casefolded name
* and the f2fs dirhash if needed, then packing all the information about this
* filename up into a 'struct f2fs_filename'.
*/
int f2fs_setup_filename(struct inode *dir, const struct qstr *iname,
int lookup, struct f2fs_filename *fname)
{
struct fscrypt_name crypt_name;
int err;
err = fscrypt_setup_filename(dir, iname, lookup, &crypt_name);
if (err)
return err;
return __f2fs_setup_filename(dir, &crypt_name, fname);
}
/*
* Prepare to look up @dentry in @dir. This is similar to
* fscrypt_prepare_lookup(), but this also handles computing the casefolded name
* and the f2fs dirhash if needed, then packing all the information about this
* filename up into a 'struct f2fs_filename'.
*/
int f2fs_prepare_lookup(struct inode *dir, struct dentry *dentry,
struct f2fs_filename *fname)
{
struct fscrypt_name crypt_name;
int err;
err = fscrypt_prepare_lookup(dir, dentry, &crypt_name);
if (err)
return err;
return __f2fs_setup_filename(dir, &crypt_name, fname);
}
void f2fs_free_filename(struct f2fs_filename *fname)
{
#ifdef CONFIG_FS_ENCRYPTION
kfree(fname->crypto_buf.name);
fname->crypto_buf.name = NULL;
#endif
#if IS_ENABLED(CONFIG_UNICODE)
if (fname->cf_name.name) {
kmem_cache_free(f2fs_cf_name_slab, fname->cf_name.name);
fname->cf_name.name = NULL;
}
#endif
}
static unsigned long dir_block_index(unsigned int level,
int dir_level, unsigned int idx)
{
unsigned long i;
unsigned long bidx = 0;
for (i = 0; i < level; i++)
bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
bidx += idx * bucket_blocks(level);
return bidx;
}
static struct f2fs_dir_entry *find_in_block(struct inode *dir,
struct page *dentry_page,
const struct f2fs_filename *fname,
int *max_slots)
{
struct f2fs_dentry_block *dentry_blk;
struct f2fs_dentry_ptr d;
dentry_blk = (struct f2fs_dentry_block *)page_address(dentry_page);
make_dentry_ptr_block(dir, &d, dentry_blk);
return f2fs_find_target_dentry(&d, fname, max_slots);
}
#if IS_ENABLED(CONFIG_UNICODE)
/*
* Test whether a case-insensitive directory entry matches the filename
* being searched for.
*
* Returns 1 for a match, 0 for no match, and -errno on an error.
*/
static int f2fs_match_ci_name(const struct inode *dir, const struct qstr *name,
const u8 *de_name, u32 de_name_len)
{
const struct super_block *sb = dir->i_sb;
const struct unicode_map *um = sb->s_encoding;
struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
struct qstr entry = QSTR_INIT(de_name, de_name_len);
int res;
if (IS_ENCRYPTED(dir)) {
const struct fscrypt_str encrypted_name =
FSTR_INIT((u8 *)de_name, de_name_len);
if (WARN_ON_ONCE(!fscrypt_has_encryption_key(dir)))
return -EINVAL;
decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
if (!decrypted_name.name)
return -ENOMEM;
res = fscrypt_fname_disk_to_usr(dir, 0, 0, &encrypted_name,
&decrypted_name);
if (res < 0)
goto out;
entry.name = decrypted_name.name;
entry.len = decrypted_name.len;
}
res = utf8_strncasecmp_folded(um, name, &entry);
/*
* In strict mode, ignore invalid names. In non-strict mode,
* fall back to treating them as opaque byte sequences.
*/
if (res < 0 && !sb_has_strict_encoding(sb)) {
res = name->len == entry.len &&
memcmp(name->name, entry.name, name->len) == 0;
} else {
/* utf8_strncasecmp_folded returns 0 on match */
res = (res == 0);
}
out:
kfree(decrypted_name.name);
return res;
}
#endif /* CONFIG_UNICODE */
static inline int f2fs_match_name(const struct inode *dir,
const struct f2fs_filename *fname,
const u8 *de_name, u32 de_name_len)
{
struct fscrypt_name f;
#if IS_ENABLED(CONFIG_UNICODE)
if (fname->cf_name.name) {
struct qstr cf = FSTR_TO_QSTR(&fname->cf_name);
return f2fs_match_ci_name(dir, &cf, de_name, de_name_len);
}
#endif
f.usr_fname = fname->usr_fname;
f.disk_name = fname->disk_name;
#ifdef CONFIG_FS_ENCRYPTION
f.crypto_buf = fname->crypto_buf;
#endif
return fscrypt_match_name(&f, de_name, de_name_len);
}
struct f2fs_dir_entry *f2fs_find_target_dentry(const struct f2fs_dentry_ptr *d,
const struct f2fs_filename *fname, int *max_slots)
{
struct f2fs_dir_entry *de;
unsigned long bit_pos = 0;
int max_len = 0;
int res = 0;
if (max_slots)
*max_slots = 0;
while (bit_pos < d->max) {
if (!test_bit_le(bit_pos, d->bitmap)) {
bit_pos++;
max_len++;
continue;
}
de = &d->dentry[bit_pos];
if (unlikely(!de->name_len)) {
bit_pos++;
continue;
}
if (de->hash_code == fname->hash) {
res = f2fs_match_name(d->inode, fname,
d->filename[bit_pos],
le16_to_cpu(de->name_len));
if (res < 0)
return ERR_PTR(res);
if (res)
goto found;
}
if (max_slots && max_len > *max_slots)
*max_slots = max_len;
max_len = 0;
bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
}
de = NULL;
found:
if (max_slots && max_len > *max_slots)
*max_slots = max_len;
return de;
}
static struct f2fs_dir_entry *find_in_level(struct inode *dir,
unsigned int level,
const struct f2fs_filename *fname,
struct page **res_page)
{
int s = GET_DENTRY_SLOTS(fname->disk_name.len);
unsigned int nbucket, nblock;
unsigned int bidx, end_block;
struct page *dentry_page;
struct f2fs_dir_entry *de = NULL;
bool room = false;
int max_slots;
nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
nblock = bucket_blocks(level);
bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
le32_to_cpu(fname->hash) % nbucket);
end_block = bidx + nblock;
for (; bidx < end_block; bidx++) {
/* no need to allocate new dentry pages to all the indices */
dentry_page = f2fs_find_data_page(dir, bidx);
if (IS_ERR(dentry_page)) {
if (PTR_ERR(dentry_page) == -ENOENT) {
room = true;
continue;
} else {
*res_page = dentry_page;
break;
}
}
de = find_in_block(dir, dentry_page, fname, &max_slots);
if (IS_ERR(de)) {
*res_page = ERR_CAST(de);
de = NULL;
break;
} else if (de) {
*res_page = dentry_page;
break;
}
if (max_slots >= s)
room = true;
f2fs_put_page(dentry_page, 0);
}
if (!de && room && F2FS_I(dir)->chash != fname->hash) {
F2FS_I(dir)->chash = fname->hash;
F2FS_I(dir)->clevel = level;
}
return de;
}
struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir,
const struct f2fs_filename *fname,
struct page **res_page)
{
unsigned long npages = dir_blocks(dir);
struct f2fs_dir_entry *de = NULL;
unsigned int max_depth;
unsigned int level;
*res_page = NULL;
if (f2fs_has_inline_dentry(dir)) {
de = f2fs_find_in_inline_dir(dir, fname, res_page);
goto out;
}
if (npages == 0)
goto out;
max_depth = F2FS_I(dir)->i_current_depth;
if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) {
f2fs_warn(F2FS_I_SB(dir), "Corrupted max_depth of %lu: %u",
dir->i_ino, max_depth);
max_depth = MAX_DIR_HASH_DEPTH;
f2fs_i_depth_write(dir, max_depth);
}
for (level = 0; level < max_depth; level++) {
de = find_in_level(dir, level, fname, res_page);
if (de || IS_ERR(*res_page))
break;
}
out:
/* This is to increase the speed of f2fs_create */
if (!de)
F2FS_I(dir)->task = current;
return de;
}
/*
* Find an entry in the specified directory with the wanted name.
* It returns the page where the entry was found (as a parameter - res_page),
* and the entry itself. Page is returned mapped and unlocked.
* Entry is guaranteed to be valid.
*/
struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
const struct qstr *child, struct page **res_page)
{
struct f2fs_dir_entry *de = NULL;
struct f2fs_filename fname;
int err;
err = f2fs_setup_filename(dir, child, 1, &fname);
if (err) {
if (err == -ENOENT)
*res_page = NULL;
else
*res_page = ERR_PTR(err);
return NULL;
}
de = __f2fs_find_entry(dir, &fname, res_page);
f2fs_free_filename(&fname);
return de;
}
struct f2fs_dir_entry *f2fs_parent_dir(struct inode *dir, struct page **p)
{
return f2fs_find_entry(dir, &dotdot_name, p);
}
ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
struct page **page)
{
ino_t res = 0;
struct f2fs_dir_entry *de;
de = f2fs_find_entry(dir, qstr, page);
if (de) {
res = le32_to_cpu(de->ino);
f2fs_put_page(*page, 0);
}
return res;
}
void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
struct page *page, struct inode *inode)
{
enum page_type type = f2fs_has_inline_dentry(dir) ? NODE : DATA;
lock_page(page);
f2fs_wait_on_page_writeback(page, type, true, true);
de->ino = cpu_to_le32(inode->i_ino);
set_de_type(de, inode->i_mode);
set_page_dirty(page);
dir->i_mtime = dir->i_ctime = current_time(dir);
f2fs_mark_inode_dirty_sync(dir, false);
f2fs_put_page(page, 1);
}
static void init_dent_inode(struct inode *dir, struct inode *inode,
const struct f2fs_filename *fname,
struct page *ipage)
{
struct f2fs_inode *ri;
if (!fname) /* tmpfile case? */
return;
f2fs_wait_on_page_writeback(ipage, NODE, true, true);
/* copy name info. to this inode page */
ri = F2FS_INODE(ipage);
ri->i_namelen = cpu_to_le32(fname->disk_name.len);
memcpy(ri->i_name, fname->disk_name.name, fname->disk_name.len);
if (IS_ENCRYPTED(dir)) {
file_set_enc_name(inode);
/*
* Roll-forward recovery doesn't have encryption keys available,
* so it can't compute the dirhash for encrypted+casefolded
* filenames. Append it to i_name if possible. Else, disable
* roll-forward recovery of the dentry (i.e., make fsync'ing the
* file force a checkpoint) by setting LOST_PINO.
*/
if (IS_CASEFOLDED(dir)) {
if (fname->disk_name.len + sizeof(f2fs_hash_t) <=
F2FS_NAME_LEN)
put_unaligned(fname->hash, (f2fs_hash_t *)
&ri->i_name[fname->disk_name.len]);
else
file_lost_pino(inode);
}
}
set_page_dirty(ipage);
}
void f2fs_do_make_empty_dir(struct inode *inode, struct inode *parent,
struct f2fs_dentry_ptr *d)
{
struct fscrypt_str dot = FSTR_INIT(".", 1);
struct fscrypt_str dotdot = FSTR_INIT("..", 2);
/* update dirent of "." */
f2fs_update_dentry(inode->i_ino, inode->i_mode, d, &dot, 0, 0);
/* update dirent of ".." */
f2fs_update_dentry(parent->i_ino, parent->i_mode, d, &dotdot, 0, 1);
}
static int make_empty_dir(struct inode *inode,
struct inode *parent, struct page *page)
{
struct page *dentry_page;
struct f2fs_dentry_block *dentry_blk;
struct f2fs_dentry_ptr d;
if (f2fs_has_inline_dentry(inode))
return f2fs_make_empty_inline_dir(inode, parent, page);
dentry_page = f2fs_get_new_data_page(inode, page, 0, true);
if (IS_ERR(dentry_page))
return PTR_ERR(dentry_page);
dentry_blk = page_address(dentry_page);
make_dentry_ptr_block(NULL, &d, dentry_blk);
f2fs_do_make_empty_dir(inode, parent, &d);
set_page_dirty(dentry_page);
f2fs_put_page(dentry_page, 1);
return 0;
}
struct page *f2fs_init_inode_metadata(struct inode *inode, struct inode *dir,
const struct f2fs_filename *fname, struct page *dpage)
{
struct page *page;
int err;
if (is_inode_flag_set(inode, FI_NEW_INODE)) {
page = f2fs_new_inode_page(inode);
if (IS_ERR(page))
return page;
if (S_ISDIR(inode->i_mode)) {
/* in order to handle error case */
get_page(page);
err = make_empty_dir(inode, dir, page);
if (err) {
lock_page(page);
goto put_error;
}
put_page(page);
}
err = f2fs_init_acl(inode, dir, page, dpage);
if (err)
goto put_error;
err = f2fs_init_security(inode, dir,
fname ? fname->usr_fname : NULL, page);
if (err)
goto put_error;
if (IS_ENCRYPTED(inode)) {
err = fscrypt_set_context(inode, page);
if (err)
goto put_error;
}
} else {
page = f2fs_get_node_page(F2FS_I_SB(dir), inode->i_ino);
if (IS_ERR(page))
return page;
}
init_dent_inode(dir, inode, fname, page);
/*
* This file should be checkpointed during fsync.
* We lost i_pino from now on.
*/
if (is_inode_flag_set(inode, FI_INC_LINK)) {
if (!S_ISDIR(inode->i_mode))
file_lost_pino(inode);
/*
* If link the tmpfile to alias through linkat path,
* we should remove this inode from orphan list.
*/
if (inode->i_nlink == 0)
f2fs_remove_orphan_inode(F2FS_I_SB(dir), inode->i_ino);
f2fs_i_links_write(inode, true);
}
return page;
put_error:
clear_nlink(inode);
f2fs_update_inode(inode, page);
f2fs_put_page(page, 1);
return ERR_PTR(err);
}
void f2fs_update_parent_metadata(struct inode *dir, struct inode *inode,
unsigned int current_depth)
{
if (inode && is_inode_flag_set(inode, FI_NEW_INODE)) {
if (S_ISDIR(inode->i_mode))
f2fs_i_links_write(dir, true);
clear_inode_flag(inode, FI_NEW_INODE);
}
dir->i_mtime = dir->i_ctime = current_time(dir);
f2fs_mark_inode_dirty_sync(dir, false);
if (F2FS_I(dir)->i_current_depth != current_depth)
f2fs_i_depth_write(dir, current_depth);
if (inode && is_inode_flag_set(inode, FI_INC_LINK))
clear_inode_flag(inode, FI_INC_LINK);
}
int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
{
int bit_start = 0;
int zero_start, zero_end;
next:
zero_start = find_next_zero_bit_le(bitmap, max_slots, bit_start);
if (zero_start >= max_slots)
return max_slots;
zero_end = find_next_bit_le(bitmap, max_slots, zero_start);
if (zero_end - zero_start >= slots)
return zero_start;
bit_start = zero_end + 1;
if (zero_end + 1 >= max_slots)
return max_slots;
goto next;
}
bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
const struct f2fs_filename *fname)
{
struct f2fs_dentry_ptr d;
unsigned int bit_pos;
int slots = GET_DENTRY_SLOTS(fname->disk_name.len);
make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
return bit_pos < d.max;
}
void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
const struct fscrypt_str *name, f2fs_hash_t name_hash,
unsigned int bit_pos)
{
struct f2fs_dir_entry *de;
int slots = GET_DENTRY_SLOTS(name->len);
int i;
de = &d->dentry[bit_pos];
de->hash_code = name_hash;
de->name_len = cpu_to_le16(name->len);
memcpy(d->filename[bit_pos], name->name, name->len);
de->ino = cpu_to_le32(ino);
set_de_type(de, mode);
for (i = 0; i < slots; i++) {
__set_bit_le(bit_pos + i, (void *)d->bitmap);
/* avoid wrong garbage data for readdir */
if (i)
(de + i)->name_len = 0;
}
}
int f2fs_add_regular_entry(struct inode *dir, const struct f2fs_filename *fname,
struct inode *inode, nid_t ino, umode_t mode)
{
unsigned int bit_pos;
unsigned int level;
unsigned int current_depth;
unsigned long bidx, block;
unsigned int nbucket, nblock;
struct page *dentry_page = NULL;
struct f2fs_dentry_block *dentry_blk = NULL;
struct f2fs_dentry_ptr d;
struct page *page = NULL;
int slots, err = 0;
level = 0;
slots = GET_DENTRY_SLOTS(fname->disk_name.len);
current_depth = F2FS_I(dir)->i_current_depth;
if (F2FS_I(dir)->chash == fname->hash) {
level = F2FS_I(dir)->clevel;
F2FS_I(dir)->chash = 0;
}
start:
if (time_to_inject(F2FS_I_SB(dir), FAULT_DIR_DEPTH)) {
f2fs_show_injection_info(F2FS_I_SB(dir), FAULT_DIR_DEPTH);
return -ENOSPC;
}
if (unlikely(current_depth == MAX_DIR_HASH_DEPTH))
return -ENOSPC;
/* Increase the depth, if required */
if (level == current_depth)
++current_depth;
nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
nblock = bucket_blocks(level);
bidx = dir_block_index(level, F2FS_I(dir)->i_dir_level,
(le32_to_cpu(fname->hash) % nbucket));
for (block = bidx; block <= (bidx + nblock - 1); block++) {
dentry_page = f2fs_get_new_data_page(dir, NULL, block, true);
if (IS_ERR(dentry_page))
return PTR_ERR(dentry_page);
dentry_blk = page_address(dentry_page);
bit_pos = f2fs_room_for_filename(&dentry_blk->dentry_bitmap,
slots, NR_DENTRY_IN_BLOCK);
if (bit_pos < NR_DENTRY_IN_BLOCK)
goto add_dentry;
f2fs_put_page(dentry_page, 1);
}
/* Move to next level to find the empty slot for new dentry */
++level;
goto start;
add_dentry:
f2fs_wait_on_page_writeback(dentry_page, DATA, true, true);
if (inode) {
f2fs_down_write(&F2FS_I(inode)->i_sem);
page = f2fs_init_inode_metadata(inode, dir, fname, NULL);
if (IS_ERR(page)) {
err = PTR_ERR(page);
goto fail;
}
}
make_dentry_ptr_block(NULL, &d, dentry_blk);
f2fs_update_dentry(ino, mode, &d, &fname->disk_name, fname->hash,
bit_pos);
set_page_dirty(dentry_page);
if (inode) {
f2fs_i_pino_write(inode, dir->i_ino);
/* synchronize inode page's data from inode cache */
if (is_inode_flag_set(inode, FI_NEW_INODE))
f2fs_update_inode(inode, page);
f2fs_put_page(page, 1);
}
f2fs_update_parent_metadata(dir, inode, current_depth);
fail:
if (inode)
f2fs_up_write(&F2FS_I(inode)->i_sem);
f2fs_put_page(dentry_page, 1);
return err;
}
int f2fs_add_dentry(struct inode *dir, const struct f2fs_filename *fname,
struct inode *inode, nid_t ino, umode_t mode)
{
int err = -EAGAIN;
if (f2fs_has_inline_dentry(dir))
err = f2fs_add_inline_entry(dir, fname, inode, ino, mode);
if (err == -EAGAIN)
err = f2fs_add_regular_entry(dir, fname, inode, ino, mode);
f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
return err;
}
/*
* Caller should grab and release a rwsem by calling f2fs_lock_op() and
* f2fs_unlock_op().
*/
int f2fs_do_add_link(struct inode *dir, const struct qstr *name,
struct inode *inode, nid_t ino, umode_t mode)
{
struct f2fs_filename fname;
struct page *page = NULL;
struct f2fs_dir_entry *de = NULL;
int err;
err = f2fs_setup_filename(dir, name, 0, &fname);
if (err)
return err;
/*
* An immature stackable filesystem shows a race condition between lookup
* and create. If we have same task when doing lookup and create, it's
* definitely fine as expected by VFS normally. Otherwise, let's just
* verify on-disk dentry one more time, which guarantees filesystem
* consistency more.
*/
if (current != F2FS_I(dir)->task) {
de = __f2fs_find_entry(dir, &fname, &page);
F2FS_I(dir)->task = NULL;
}
if (de) {
f2fs_put_page(page, 0);
err = -EEXIST;
} else if (IS_ERR(page)) {
err = PTR_ERR(page);
} else {
err = f2fs_add_dentry(dir, &fname, inode, ino, mode);
}
f2fs_free_filename(&fname);
return err;
}
int f2fs_do_tmpfile(struct inode *inode, struct inode *dir)
{
struct page *page;
int err = 0;
f2fs_down_write(&F2FS_I(inode)->i_sem);
page = f2fs_init_inode_metadata(inode, dir, NULL, NULL);
if (IS_ERR(page)) {
err = PTR_ERR(page);
goto fail;
}
f2fs_put_page(page, 1);
clear_inode_flag(inode, FI_NEW_INODE);
f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
fail:
f2fs_up_write(&F2FS_I(inode)->i_sem);
return err;
}
void f2fs_drop_nlink(struct inode *dir, struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
f2fs_down_write(&F2FS_I(inode)->i_sem);
if (S_ISDIR(inode->i_mode))
f2fs_i_links_write(dir, false);
inode->i_ctime = current_time(inode);
f2fs_i_links_write(inode, false);
if (S_ISDIR(inode->i_mode)) {
f2fs_i_links_write(inode, false);
f2fs_i_size_write(inode, 0);
}
f2fs_up_write(&F2FS_I(inode)->i_sem);
if (inode->i_nlink == 0)
f2fs_add_orphan_inode(inode);
else
f2fs_release_orphan_inode(sbi);
}
/*
* It only removes the dentry from the dentry page, corresponding name
* entry in name page does not need to be touched during deletion.
*/
void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
struct inode *dir, struct inode *inode)
{
struct f2fs_dentry_block *dentry_blk;
unsigned int bit_pos;
int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
int i;
f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
if (F2FS_OPTION(F2FS_I_SB(dir)).fsync_mode == FSYNC_MODE_STRICT)
f2fs_add_ino_entry(F2FS_I_SB(dir), dir->i_ino, TRANS_DIR_INO);
if (f2fs_has_inline_dentry(dir))
return f2fs_delete_inline_entry(dentry, page, dir, inode);
lock_page(page);
f2fs_wait_on_page_writeback(page, DATA, true, true);
dentry_blk = page_address(page);
bit_pos = dentry - dentry_blk->dentry;
for (i = 0; i < slots; i++)
__clear_bit_le(bit_pos + i, &dentry_blk->dentry_bitmap);
/* Let's check and deallocate this dentry page */
bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
NR_DENTRY_IN_BLOCK,
0);
set_page_dirty(page);
if (bit_pos == NR_DENTRY_IN_BLOCK &&
!f2fs_truncate_hole(dir, page->index, page->index + 1)) {
f2fs_clear_page_cache_dirty_tag(page);
clear_page_dirty_for_io(page);
ClearPageUptodate(page);
clear_page_private_gcing(page);
inode_dec_dirty_pages(dir);
f2fs_remove_dirty_inode(dir);
detach_page_private(page);
set_page_private(page, 0);
}
f2fs_put_page(page, 1);
dir->i_ctime = dir->i_mtime = current_time(dir);
f2fs_mark_inode_dirty_sync(dir, false);
if (inode)
f2fs_drop_nlink(dir, inode);
}
bool f2fs_empty_dir(struct inode *dir)
{
unsigned long bidx;
struct page *dentry_page;
unsigned int bit_pos;
struct f2fs_dentry_block *dentry_blk;
unsigned long nblock = dir_blocks(dir);
if (f2fs_has_inline_dentry(dir))
return f2fs_empty_inline_dir(dir);
for (bidx = 0; bidx < nblock; bidx++) {
dentry_page = f2fs_get_lock_data_page(dir, bidx, false);
if (IS_ERR(dentry_page)) {
if (PTR_ERR(dentry_page) == -ENOENT)
continue;
else
return false;
}
dentry_blk = page_address(dentry_page);
if (bidx == 0)
bit_pos = 2;
else
bit_pos = 0;
bit_pos = find_next_bit_le(&dentry_blk->dentry_bitmap,
NR_DENTRY_IN_BLOCK,
bit_pos);
f2fs_put_page(dentry_page, 1);
if (bit_pos < NR_DENTRY_IN_BLOCK)
return false;
}
return true;
}
int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
unsigned int start_pos, struct fscrypt_str *fstr)
{
unsigned char d_type = DT_UNKNOWN;
unsigned int bit_pos;
struct f2fs_dir_entry *de = NULL;
struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
struct f2fs_sb_info *sbi = F2FS_I_SB(d->inode);
struct blk_plug plug;
bool readdir_ra = sbi->readdir_ra == 1;
bool found_valid_dirent = false;
int err = 0;
bit_pos = ((unsigned long)ctx->pos % d->max);
if (readdir_ra)
blk_start_plug(&plug);
while (bit_pos < d->max) {
bit_pos = find_next_bit_le(d->bitmap, d->max, bit_pos);
if (bit_pos >= d->max)
break;
de = &d->dentry[bit_pos];
if (de->name_len == 0) {
if (found_valid_dirent || !bit_pos) {
printk_ratelimited(
"%sF2FS-fs (%s): invalid namelen(0), ino:%u, run fsck to fix.",
KERN_WARNING, sbi->sb->s_id,
le32_to_cpu(de->ino));
set_sbi_flag(sbi, SBI_NEED_FSCK);
}
bit_pos++;
ctx->pos = start_pos + bit_pos;
continue;
}
d_type = f2fs_get_de_type(de);
de_name.name = d->filename[bit_pos];
de_name.len = le16_to_cpu(de->name_len);
/* check memory boundary before moving forward */
bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
if (unlikely(bit_pos > d->max ||
le16_to_cpu(de->name_len) > F2FS_NAME_LEN)) {
f2fs_warn(sbi, "%s: corrupted namelen=%d, run fsck to fix.",
__func__, le16_to_cpu(de->name_len));
set_sbi_flag(sbi, SBI_NEED_FSCK);
err = -EFSCORRUPTED;
goto out;
}
if (IS_ENCRYPTED(d->inode)) {
int save_len = fstr->len;
err = fscrypt_fname_disk_to_usr(d->inode,
(u32)le32_to_cpu(de->hash_code),
0, &de_name, fstr);
if (err)
goto out;
de_name = *fstr;
fstr->len = save_len;
}
if (!dir_emit(ctx, de_name.name, de_name.len,
le32_to_cpu(de->ino), d_type)) {
err = 1;
goto out;
}
if (readdir_ra)
f2fs_ra_node_page(sbi, le32_to_cpu(de->ino));
ctx->pos = start_pos + bit_pos;
found_valid_dirent = true;
}
out:
if (readdir_ra)
blk_finish_plug(&plug);
return err;
}
static int f2fs_readdir(struct file *file, struct dir_context *ctx)
{
struct inode *inode = file_inode(file);
unsigned long npages = dir_blocks(inode);
struct f2fs_dentry_block *dentry_blk = NULL;
struct page *dentry_page = NULL;
struct file_ra_state *ra = &file->f_ra;
loff_t start_pos = ctx->pos;
unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
struct f2fs_dentry_ptr d;
struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
int err = 0;
if (IS_ENCRYPTED(inode)) {
err = fscrypt_prepare_readdir(inode);
if (err)
goto out;
err = fscrypt_fname_alloc_buffer(F2FS_NAME_LEN, &fstr);
if (err < 0)
goto out;
}
if (f2fs_has_inline_dentry(inode)) {
err = f2fs_read_inline_dir(file, ctx, &fstr);
goto out_free;
}
for (; n < npages; n++, ctx->pos = n * NR_DENTRY_IN_BLOCK) {
/* allow readdir() to be interrupted */
if (fatal_signal_pending(current)) {
err = -ERESTARTSYS;
goto out_free;
}
cond_resched();
/* readahead for multi pages of dir */
if (npages - n > 1 && !ra_has_index(ra, n))
page_cache_sync_readahead(inode->i_mapping, ra, file, n,
min(npages - n, (pgoff_t)MAX_DIR_RA_PAGES));
dentry_page = f2fs_find_data_page(inode, n);
if (IS_ERR(dentry_page)) {
err = PTR_ERR(dentry_page);
if (err == -ENOENT) {
err = 0;
continue;
} else {
goto out_free;
}
}
dentry_blk = page_address(dentry_page);
make_dentry_ptr_block(inode, &d, dentry_blk);
err = f2fs_fill_dentries(ctx, &d,
n * NR_DENTRY_IN_BLOCK, &fstr);
if (err) {
f2fs_put_page(dentry_page, 0);
break;
}
f2fs_put_page(dentry_page, 0);
}
out_free:
fscrypt_fname_free_buffer(&fstr);
out:
trace_f2fs_readdir(inode, start_pos, ctx->pos, err);
return err < 0 ? err : 0;
}
const struct file_operations f2fs_dir_operations = {
.llseek = generic_file_llseek,
.read = generic_read_dir,
.iterate_shared = f2fs_readdir,
.fsync = f2fs_sync_file,
.unlocked_ioctl = f2fs_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = f2fs_compat_ioctl,
#endif
};