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3119 lines
81 KiB
3119 lines
81 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* linux/fs/ext4/xattr.c |
|
* |
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* Copyright (C) 2001-2003 Andreas Gruenbacher, <[email protected]> |
|
* |
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* Fix by Harrison Xing <[email protected]>. |
|
* Ext4 code with a lot of help from Eric Jarman <[email protected]>. |
|
* Extended attributes for symlinks and special files added per |
|
* suggestion of Luka Renko <[email protected]>. |
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* xattr consolidation Copyright (c) 2004 James Morris <[email protected]>, |
|
* Red Hat Inc. |
|
* ea-in-inode support by Alex Tomas <[email protected]> aka bzzz |
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* and Andreas Gruenbacher <[email protected]>. |
|
*/ |
|
|
|
/* |
|
* Extended attributes are stored directly in inodes (on file systems with |
|
* inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl |
|
* field contains the block number if an inode uses an additional block. All |
|
* attributes must fit in the inode and one additional block. Blocks that |
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* contain the identical set of attributes may be shared among several inodes. |
|
* Identical blocks are detected by keeping a cache of blocks that have |
|
* recently been accessed. |
|
* |
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* The attributes in inodes and on blocks have a different header; the entries |
|
* are stored in the same format: |
|
* |
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* +------------------+ |
|
* | header | |
|
* | entry 1 | | |
|
* | entry 2 | | growing downwards |
|
* | entry 3 | v |
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* | four null bytes | |
|
* | . . . | |
|
* | value 1 | ^ |
|
* | value 3 | | growing upwards |
|
* | value 2 | | |
|
* +------------------+ |
|
* |
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* The header is followed by multiple entry descriptors. In disk blocks, the |
|
* entry descriptors are kept sorted. In inodes, they are unsorted. The |
|
* attribute values are aligned to the end of the block in no specific order. |
|
* |
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* Locking strategy |
|
* ---------------- |
|
* EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem. |
|
* EA blocks are only changed if they are exclusive to an inode, so |
|
* holding xattr_sem also means that nothing but the EA block's reference |
|
* count can change. Multiple writers to the same block are synchronized |
|
* by the buffer lock. |
|
*/ |
|
|
|
#include <linux/init.h> |
|
#include <linux/fs.h> |
|
#include <linux/slab.h> |
|
#include <linux/mbcache.h> |
|
#include <linux/quotaops.h> |
|
#include <linux/iversion.h> |
|
#include "ext4_jbd2.h" |
|
#include "ext4.h" |
|
#include "xattr.h" |
|
#include "acl.h" |
|
|
|
#ifdef EXT4_XATTR_DEBUG |
|
# define ea_idebug(inode, fmt, ...) \ |
|
printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \ |
|
inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__) |
|
# define ea_bdebug(bh, fmt, ...) \ |
|
printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \ |
|
bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__) |
|
#else |
|
# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
|
# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) |
|
#endif |
|
|
|
static void ext4_xattr_block_cache_insert(struct mb_cache *, |
|
struct buffer_head *); |
|
static struct buffer_head * |
|
ext4_xattr_block_cache_find(struct inode *, struct ext4_xattr_header *, |
|
struct mb_cache_entry **); |
|
static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value, |
|
size_t value_count); |
|
static void ext4_xattr_rehash(struct ext4_xattr_header *); |
|
|
|
static const struct xattr_handler * const ext4_xattr_handler_map[] = { |
|
[EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, |
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#ifdef CONFIG_EXT4_FS_POSIX_ACL |
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[EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, |
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[EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, |
|
#endif |
|
[EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, |
|
#ifdef CONFIG_EXT4_FS_SECURITY |
|
[EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, |
|
#endif |
|
[EXT4_XATTR_INDEX_HURD] = &ext4_xattr_hurd_handler, |
|
}; |
|
|
|
const struct xattr_handler *ext4_xattr_handlers[] = { |
|
&ext4_xattr_user_handler, |
|
&ext4_xattr_trusted_handler, |
|
#ifdef CONFIG_EXT4_FS_POSIX_ACL |
|
&posix_acl_access_xattr_handler, |
|
&posix_acl_default_xattr_handler, |
|
#endif |
|
#ifdef CONFIG_EXT4_FS_SECURITY |
|
&ext4_xattr_security_handler, |
|
#endif |
|
&ext4_xattr_hurd_handler, |
|
NULL |
|
}; |
|
|
|
#define EA_BLOCK_CACHE(inode) (((struct ext4_sb_info *) \ |
|
inode->i_sb->s_fs_info)->s_ea_block_cache) |
|
|
|
#define EA_INODE_CACHE(inode) (((struct ext4_sb_info *) \ |
|
inode->i_sb->s_fs_info)->s_ea_inode_cache) |
|
|
|
static int |
|
ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, |
|
struct inode *inode); |
|
|
|
#ifdef CONFIG_LOCKDEP |
|
void ext4_xattr_inode_set_class(struct inode *ea_inode) |
|
{ |
|
lockdep_set_subclass(&ea_inode->i_rwsem, 1); |
|
} |
|
#endif |
|
|
|
static __le32 ext4_xattr_block_csum(struct inode *inode, |
|
sector_t block_nr, |
|
struct ext4_xattr_header *hdr) |
|
{ |
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
|
__u32 csum; |
|
__le64 dsk_block_nr = cpu_to_le64(block_nr); |
|
__u32 dummy_csum = 0; |
|
int offset = offsetof(struct ext4_xattr_header, h_checksum); |
|
|
|
csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, |
|
sizeof(dsk_block_nr)); |
|
csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset); |
|
csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); |
|
offset += sizeof(dummy_csum); |
|
csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset, |
|
EXT4_BLOCK_SIZE(inode->i_sb) - offset); |
|
|
|
return cpu_to_le32(csum); |
|
} |
|
|
|
static int ext4_xattr_block_csum_verify(struct inode *inode, |
|
struct buffer_head *bh) |
|
{ |
|
struct ext4_xattr_header *hdr = BHDR(bh); |
|
int ret = 1; |
|
|
|
if (ext4_has_metadata_csum(inode->i_sb)) { |
|
lock_buffer(bh); |
|
ret = (hdr->h_checksum == ext4_xattr_block_csum(inode, |
|
bh->b_blocknr, hdr)); |
|
unlock_buffer(bh); |
|
} |
|
return ret; |
|
} |
|
|
|
static void ext4_xattr_block_csum_set(struct inode *inode, |
|
struct buffer_head *bh) |
|
{ |
|
if (ext4_has_metadata_csum(inode->i_sb)) |
|
BHDR(bh)->h_checksum = ext4_xattr_block_csum(inode, |
|
bh->b_blocknr, BHDR(bh)); |
|
} |
|
|
|
static inline const struct xattr_handler * |
|
ext4_xattr_handler(int name_index) |
|
{ |
|
const struct xattr_handler *handler = NULL; |
|
|
|
if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) |
|
handler = ext4_xattr_handler_map[name_index]; |
|
return handler; |
|
} |
|
|
|
static int |
|
ext4_xattr_check_entries(struct ext4_xattr_entry *entry, void *end, |
|
void *value_start) |
|
{ |
|
struct ext4_xattr_entry *e = entry; |
|
|
|
/* Find the end of the names list */ |
|
while (!IS_LAST_ENTRY(e)) { |
|
struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); |
|
if ((void *)next >= end) |
|
return -EFSCORRUPTED; |
|
if (strnlen(e->e_name, e->e_name_len) != e->e_name_len) |
|
return -EFSCORRUPTED; |
|
e = next; |
|
} |
|
|
|
/* Check the values */ |
|
while (!IS_LAST_ENTRY(entry)) { |
|
u32 size = le32_to_cpu(entry->e_value_size); |
|
|
|
if (size > EXT4_XATTR_SIZE_MAX) |
|
return -EFSCORRUPTED; |
|
|
|
if (size != 0 && entry->e_value_inum == 0) { |
|
u16 offs = le16_to_cpu(entry->e_value_offs); |
|
void *value; |
|
|
|
/* |
|
* The value cannot overlap the names, and the value |
|
* with padding cannot extend beyond 'end'. Check both |
|
* the padded and unpadded sizes, since the size may |
|
* overflow to 0 when adding padding. |
|
*/ |
|
if (offs > end - value_start) |
|
return -EFSCORRUPTED; |
|
value = value_start + offs; |
|
if (value < (void *)e + sizeof(u32) || |
|
size > end - value || |
|
EXT4_XATTR_SIZE(size) > end - value) |
|
return -EFSCORRUPTED; |
|
} |
|
entry = EXT4_XATTR_NEXT(entry); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static inline int |
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__ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh, |
|
const char *function, unsigned int line) |
|
{ |
|
int error = -EFSCORRUPTED; |
|
|
|
if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || |
|
BHDR(bh)->h_blocks != cpu_to_le32(1)) |
|
goto errout; |
|
if (buffer_verified(bh)) |
|
return 0; |
|
|
|
error = -EFSBADCRC; |
|
if (!ext4_xattr_block_csum_verify(inode, bh)) |
|
goto errout; |
|
error = ext4_xattr_check_entries(BFIRST(bh), bh->b_data + bh->b_size, |
|
bh->b_data); |
|
errout: |
|
if (error) |
|
__ext4_error_inode(inode, function, line, 0, -error, |
|
"corrupted xattr block %llu", |
|
(unsigned long long) bh->b_blocknr); |
|
else |
|
set_buffer_verified(bh); |
|
return error; |
|
} |
|
|
|
#define ext4_xattr_check_block(inode, bh) \ |
|
__ext4_xattr_check_block((inode), (bh), __func__, __LINE__) |
|
|
|
|
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static int |
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__xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, |
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void *end, const char *function, unsigned int line) |
|
{ |
|
int error = -EFSCORRUPTED; |
|
|
|
if (end - (void *)header < sizeof(*header) + sizeof(u32) || |
|
(header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC))) |
|
goto errout; |
|
error = ext4_xattr_check_entries(IFIRST(header), end, IFIRST(header)); |
|
errout: |
|
if (error) |
|
__ext4_error_inode(inode, function, line, 0, -error, |
|
"corrupted in-inode xattr"); |
|
return error; |
|
} |
|
|
|
#define xattr_check_inode(inode, header, end) \ |
|
__xattr_check_inode((inode), (header), (end), __func__, __LINE__) |
|
|
|
static int |
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xattr_find_entry(struct inode *inode, struct ext4_xattr_entry **pentry, |
|
void *end, int name_index, const char *name, int sorted) |
|
{ |
|
struct ext4_xattr_entry *entry, *next; |
|
size_t name_len; |
|
int cmp = 1; |
|
|
|
if (name == NULL) |
|
return -EINVAL; |
|
name_len = strlen(name); |
|
for (entry = *pentry; !IS_LAST_ENTRY(entry); entry = next) { |
|
next = EXT4_XATTR_NEXT(entry); |
|
if ((void *) next >= end) { |
|
EXT4_ERROR_INODE(inode, "corrupted xattr entries"); |
|
return -EFSCORRUPTED; |
|
} |
|
cmp = name_index - entry->e_name_index; |
|
if (!cmp) |
|
cmp = name_len - entry->e_name_len; |
|
if (!cmp) |
|
cmp = memcmp(name, entry->e_name, name_len); |
|
if (cmp <= 0 && (sorted || cmp == 0)) |
|
break; |
|
} |
|
*pentry = entry; |
|
return cmp ? -ENODATA : 0; |
|
} |
|
|
|
static u32 |
|
ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size) |
|
{ |
|
return ext4_chksum(sbi, sbi->s_csum_seed, buffer, size); |
|
} |
|
|
|
static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode) |
|
{ |
|
return ((u64)ea_inode->i_ctime.tv_sec << 32) | |
|
(u32) inode_peek_iversion_raw(ea_inode); |
|
} |
|
|
|
static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count) |
|
{ |
|
ea_inode->i_ctime.tv_sec = (u32)(ref_count >> 32); |
|
inode_set_iversion_raw(ea_inode, ref_count & 0xffffffff); |
|
} |
|
|
|
static u32 ext4_xattr_inode_get_hash(struct inode *ea_inode) |
|
{ |
|
return (u32)ea_inode->i_atime.tv_sec; |
|
} |
|
|
|
static void ext4_xattr_inode_set_hash(struct inode *ea_inode, u32 hash) |
|
{ |
|
ea_inode->i_atime.tv_sec = hash; |
|
} |
|
|
|
/* |
|
* Read the EA value from an inode. |
|
*/ |
|
static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size) |
|
{ |
|
int blocksize = 1 << ea_inode->i_blkbits; |
|
int bh_count = (size + blocksize - 1) >> ea_inode->i_blkbits; |
|
int tail_size = (size % blocksize) ?: blocksize; |
|
struct buffer_head *bhs_inline[8]; |
|
struct buffer_head **bhs = bhs_inline; |
|
int i, ret; |
|
|
|
if (bh_count > ARRAY_SIZE(bhs_inline)) { |
|
bhs = kmalloc_array(bh_count, sizeof(*bhs), GFP_NOFS); |
|
if (!bhs) |
|
return -ENOMEM; |
|
} |
|
|
|
ret = ext4_bread_batch(ea_inode, 0 /* block */, bh_count, |
|
true /* wait */, bhs); |
|
if (ret) |
|
goto free_bhs; |
|
|
|
for (i = 0; i < bh_count; i++) { |
|
/* There shouldn't be any holes in ea_inode. */ |
|
if (!bhs[i]) { |
|
ret = -EFSCORRUPTED; |
|
goto put_bhs; |
|
} |
|
memcpy((char *)buf + blocksize * i, bhs[i]->b_data, |
|
i < bh_count - 1 ? blocksize : tail_size); |
|
} |
|
ret = 0; |
|
put_bhs: |
|
for (i = 0; i < bh_count; i++) |
|
brelse(bhs[i]); |
|
free_bhs: |
|
if (bhs != bhs_inline) |
|
kfree(bhs); |
|
return ret; |
|
} |
|
|
|
#define EXT4_XATTR_INODE_GET_PARENT(inode) ((__u32)(inode)->i_mtime.tv_sec) |
|
|
|
static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino, |
|
u32 ea_inode_hash, struct inode **ea_inode) |
|
{ |
|
struct inode *inode; |
|
int err; |
|
|
|
inode = ext4_iget(parent->i_sb, ea_ino, EXT4_IGET_NORMAL); |
|
if (IS_ERR(inode)) { |
|
err = PTR_ERR(inode); |
|
ext4_error(parent->i_sb, |
|
"error while reading EA inode %lu err=%d", ea_ino, |
|
err); |
|
return err; |
|
} |
|
|
|
if (is_bad_inode(inode)) { |
|
ext4_error(parent->i_sb, |
|
"error while reading EA inode %lu is_bad_inode", |
|
ea_ino); |
|
err = -EIO; |
|
goto error; |
|
} |
|
|
|
if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) { |
|
ext4_error(parent->i_sb, |
|
"EA inode %lu does not have EXT4_EA_INODE_FL flag", |
|
ea_ino); |
|
err = -EINVAL; |
|
goto error; |
|
} |
|
|
|
ext4_xattr_inode_set_class(inode); |
|
|
|
/* |
|
* Check whether this is an old Lustre-style xattr inode. Lustre |
|
* implementation does not have hash validation, rather it has a |
|
* backpointer from ea_inode to the parent inode. |
|
*/ |
|
if (ea_inode_hash != ext4_xattr_inode_get_hash(inode) && |
|
EXT4_XATTR_INODE_GET_PARENT(inode) == parent->i_ino && |
|
inode->i_generation == parent->i_generation) { |
|
ext4_set_inode_state(inode, EXT4_STATE_LUSTRE_EA_INODE); |
|
ext4_xattr_inode_set_ref(inode, 1); |
|
} else { |
|
inode_lock(inode); |
|
inode->i_flags |= S_NOQUOTA; |
|
inode_unlock(inode); |
|
} |
|
|
|
*ea_inode = inode; |
|
return 0; |
|
error: |
|
iput(inode); |
|
return err; |
|
} |
|
|
|
static int |
|
ext4_xattr_inode_verify_hashes(struct inode *ea_inode, |
|
struct ext4_xattr_entry *entry, void *buffer, |
|
size_t size) |
|
{ |
|
u32 hash; |
|
|
|
/* Verify stored hash matches calculated hash. */ |
|
hash = ext4_xattr_inode_hash(EXT4_SB(ea_inode->i_sb), buffer, size); |
|
if (hash != ext4_xattr_inode_get_hash(ea_inode)) |
|
return -EFSCORRUPTED; |
|
|
|
if (entry) { |
|
__le32 e_hash, tmp_data; |
|
|
|
/* Verify entry hash. */ |
|
tmp_data = cpu_to_le32(hash); |
|
e_hash = ext4_xattr_hash_entry(entry->e_name, entry->e_name_len, |
|
&tmp_data, 1); |
|
if (e_hash != entry->e_hash) |
|
return -EFSCORRUPTED; |
|
} |
|
return 0; |
|
} |
|
|
|
/* |
|
* Read xattr value from the EA inode. |
|
*/ |
|
static int |
|
ext4_xattr_inode_get(struct inode *inode, struct ext4_xattr_entry *entry, |
|
void *buffer, size_t size) |
|
{ |
|
struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); |
|
struct inode *ea_inode; |
|
int err; |
|
|
|
err = ext4_xattr_inode_iget(inode, le32_to_cpu(entry->e_value_inum), |
|
le32_to_cpu(entry->e_hash), &ea_inode); |
|
if (err) { |
|
ea_inode = NULL; |
|
goto out; |
|
} |
|
|
|
if (i_size_read(ea_inode) != size) { |
|
ext4_warning_inode(ea_inode, |
|
"ea_inode file size=%llu entry size=%zu", |
|
i_size_read(ea_inode), size); |
|
err = -EFSCORRUPTED; |
|
goto out; |
|
} |
|
|
|
err = ext4_xattr_inode_read(ea_inode, buffer, size); |
|
if (err) |
|
goto out; |
|
|
|
if (!ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE)) { |
|
err = ext4_xattr_inode_verify_hashes(ea_inode, entry, buffer, |
|
size); |
|
if (err) { |
|
ext4_warning_inode(ea_inode, |
|
"EA inode hash validation failed"); |
|
goto out; |
|
} |
|
|
|
if (ea_inode_cache) |
|
mb_cache_entry_create(ea_inode_cache, GFP_NOFS, |
|
ext4_xattr_inode_get_hash(ea_inode), |
|
ea_inode->i_ino, true /* reusable */); |
|
} |
|
out: |
|
iput(ea_inode); |
|
return err; |
|
} |
|
|
|
static int |
|
ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, |
|
void *buffer, size_t buffer_size) |
|
{ |
|
struct buffer_head *bh = NULL; |
|
struct ext4_xattr_entry *entry; |
|
size_t size; |
|
void *end; |
|
int error; |
|
struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); |
|
|
|
ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", |
|
name_index, name, buffer, (long)buffer_size); |
|
|
|
if (!EXT4_I(inode)->i_file_acl) |
|
return -ENODATA; |
|
ea_idebug(inode, "reading block %llu", |
|
(unsigned long long)EXT4_I(inode)->i_file_acl); |
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) |
|
return PTR_ERR(bh); |
|
ea_bdebug(bh, "b_count=%d, refcount=%d", |
|
atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); |
|
error = ext4_xattr_check_block(inode, bh); |
|
if (error) |
|
goto cleanup; |
|
ext4_xattr_block_cache_insert(ea_block_cache, bh); |
|
entry = BFIRST(bh); |
|
end = bh->b_data + bh->b_size; |
|
error = xattr_find_entry(inode, &entry, end, name_index, name, 1); |
|
if (error) |
|
goto cleanup; |
|
size = le32_to_cpu(entry->e_value_size); |
|
error = -ERANGE; |
|
if (unlikely(size > EXT4_XATTR_SIZE_MAX)) |
|
goto cleanup; |
|
if (buffer) { |
|
if (size > buffer_size) |
|
goto cleanup; |
|
if (entry->e_value_inum) { |
|
error = ext4_xattr_inode_get(inode, entry, buffer, |
|
size); |
|
if (error) |
|
goto cleanup; |
|
} else { |
|
u16 offset = le16_to_cpu(entry->e_value_offs); |
|
void *p = bh->b_data + offset; |
|
|
|
if (unlikely(p + size > end)) |
|
goto cleanup; |
|
memcpy(buffer, p, size); |
|
} |
|
} |
|
error = size; |
|
|
|
cleanup: |
|
brelse(bh); |
|
return error; |
|
} |
|
|
|
int |
|
ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, |
|
void *buffer, size_t buffer_size) |
|
{ |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_xattr_entry *entry; |
|
struct ext4_inode *raw_inode; |
|
struct ext4_iloc iloc; |
|
size_t size; |
|
void *end; |
|
int error; |
|
|
|
if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
|
return -ENODATA; |
|
error = ext4_get_inode_loc(inode, &iloc); |
|
if (error) |
|
return error; |
|
raw_inode = ext4_raw_inode(&iloc); |
|
header = IHDR(inode, raw_inode); |
|
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
|
error = xattr_check_inode(inode, header, end); |
|
if (error) |
|
goto cleanup; |
|
entry = IFIRST(header); |
|
error = xattr_find_entry(inode, &entry, end, name_index, name, 0); |
|
if (error) |
|
goto cleanup; |
|
size = le32_to_cpu(entry->e_value_size); |
|
error = -ERANGE; |
|
if (unlikely(size > EXT4_XATTR_SIZE_MAX)) |
|
goto cleanup; |
|
if (buffer) { |
|
if (size > buffer_size) |
|
goto cleanup; |
|
if (entry->e_value_inum) { |
|
error = ext4_xattr_inode_get(inode, entry, buffer, |
|
size); |
|
if (error) |
|
goto cleanup; |
|
} else { |
|
u16 offset = le16_to_cpu(entry->e_value_offs); |
|
void *p = (void *)IFIRST(header) + offset; |
|
|
|
if (unlikely(p + size > end)) |
|
goto cleanup; |
|
memcpy(buffer, p, size); |
|
} |
|
} |
|
error = size; |
|
|
|
cleanup: |
|
brelse(iloc.bh); |
|
return error; |
|
} |
|
|
|
/* |
|
* ext4_xattr_get() |
|
* |
|
* Copy an extended attribute into the buffer |
|
* provided, or compute the buffer size required. |
|
* Buffer is NULL to compute the size of the buffer required. |
|
* |
|
* Returns a negative error number on failure, or the number of bytes |
|
* used / required on success. |
|
*/ |
|
int |
|
ext4_xattr_get(struct inode *inode, int name_index, const char *name, |
|
void *buffer, size_t buffer_size) |
|
{ |
|
int error; |
|
|
|
if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) |
|
return -EIO; |
|
|
|
if (strlen(name) > 255) |
|
return -ERANGE; |
|
|
|
down_read(&EXT4_I(inode)->xattr_sem); |
|
error = ext4_xattr_ibody_get(inode, name_index, name, buffer, |
|
buffer_size); |
|
if (error == -ENODATA) |
|
error = ext4_xattr_block_get(inode, name_index, name, buffer, |
|
buffer_size); |
|
up_read(&EXT4_I(inode)->xattr_sem); |
|
return error; |
|
} |
|
|
|
static int |
|
ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, |
|
char *buffer, size_t buffer_size) |
|
{ |
|
size_t rest = buffer_size; |
|
|
|
for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { |
|
const struct xattr_handler *handler = |
|
ext4_xattr_handler(entry->e_name_index); |
|
|
|
if (handler && (!handler->list || handler->list(dentry))) { |
|
const char *prefix = handler->prefix ?: handler->name; |
|
size_t prefix_len = strlen(prefix); |
|
size_t size = prefix_len + entry->e_name_len + 1; |
|
|
|
if (buffer) { |
|
if (size > rest) |
|
return -ERANGE; |
|
memcpy(buffer, prefix, prefix_len); |
|
buffer += prefix_len; |
|
memcpy(buffer, entry->e_name, entry->e_name_len); |
|
buffer += entry->e_name_len; |
|
*buffer++ = 0; |
|
} |
|
rest -= size; |
|
} |
|
} |
|
return buffer_size - rest; /* total size */ |
|
} |
|
|
|
static int |
|
ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
|
{ |
|
struct inode *inode = d_inode(dentry); |
|
struct buffer_head *bh = NULL; |
|
int error; |
|
|
|
ea_idebug(inode, "buffer=%p, buffer_size=%ld", |
|
buffer, (long)buffer_size); |
|
|
|
if (!EXT4_I(inode)->i_file_acl) |
|
return 0; |
|
ea_idebug(inode, "reading block %llu", |
|
(unsigned long long)EXT4_I(inode)->i_file_acl); |
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) |
|
return PTR_ERR(bh); |
|
ea_bdebug(bh, "b_count=%d, refcount=%d", |
|
atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); |
|
error = ext4_xattr_check_block(inode, bh); |
|
if (error) |
|
goto cleanup; |
|
ext4_xattr_block_cache_insert(EA_BLOCK_CACHE(inode), bh); |
|
error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, |
|
buffer_size); |
|
cleanup: |
|
brelse(bh); |
|
return error; |
|
} |
|
|
|
static int |
|
ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) |
|
{ |
|
struct inode *inode = d_inode(dentry); |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_inode *raw_inode; |
|
struct ext4_iloc iloc; |
|
void *end; |
|
int error; |
|
|
|
if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) |
|
return 0; |
|
error = ext4_get_inode_loc(inode, &iloc); |
|
if (error) |
|
return error; |
|
raw_inode = ext4_raw_inode(&iloc); |
|
header = IHDR(inode, raw_inode); |
|
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
|
error = xattr_check_inode(inode, header, end); |
|
if (error) |
|
goto cleanup; |
|
error = ext4_xattr_list_entries(dentry, IFIRST(header), |
|
buffer, buffer_size); |
|
|
|
cleanup: |
|
brelse(iloc.bh); |
|
return error; |
|
} |
|
|
|
/* |
|
* Inode operation listxattr() |
|
* |
|
* d_inode(dentry)->i_rwsem: don't care |
|
* |
|
* Copy a list of attribute names into the buffer |
|
* provided, or compute the buffer size required. |
|
* Buffer is NULL to compute the size of the buffer required. |
|
* |
|
* Returns a negative error number on failure, or the number of bytes |
|
* used / required on success. |
|
*/ |
|
ssize_t |
|
ext4_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) |
|
{ |
|
int ret, ret2; |
|
|
|
down_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
|
ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); |
|
if (ret < 0) |
|
goto errout; |
|
if (buffer) { |
|
buffer += ret; |
|
buffer_size -= ret; |
|
} |
|
ret = ext4_xattr_block_list(dentry, buffer, buffer_size); |
|
if (ret < 0) |
|
goto errout; |
|
ret += ret2; |
|
errout: |
|
up_read(&EXT4_I(d_inode(dentry))->xattr_sem); |
|
return ret; |
|
} |
|
|
|
/* |
|
* If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is |
|
* not set, set it. |
|
*/ |
|
static void ext4_xattr_update_super_block(handle_t *handle, |
|
struct super_block *sb) |
|
{ |
|
if (ext4_has_feature_xattr(sb)) |
|
return; |
|
|
|
BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); |
|
if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { |
|
lock_buffer(EXT4_SB(sb)->s_sbh); |
|
ext4_set_feature_xattr(sb); |
|
ext4_superblock_csum_set(sb); |
|
unlock_buffer(EXT4_SB(sb)->s_sbh); |
|
ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); |
|
} |
|
} |
|
|
|
int ext4_get_inode_usage(struct inode *inode, qsize_t *usage) |
|
{ |
|
struct ext4_iloc iloc = { .bh = NULL }; |
|
struct buffer_head *bh = NULL; |
|
struct ext4_inode *raw_inode; |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_xattr_entry *entry; |
|
qsize_t ea_inode_refs = 0; |
|
void *end; |
|
int ret; |
|
|
|
lockdep_assert_held_read(&EXT4_I(inode)->xattr_sem); |
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
|
ret = ext4_get_inode_loc(inode, &iloc); |
|
if (ret) |
|
goto out; |
|
raw_inode = ext4_raw_inode(&iloc); |
|
header = IHDR(inode, raw_inode); |
|
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
|
ret = xattr_check_inode(inode, header, end); |
|
if (ret) |
|
goto out; |
|
|
|
for (entry = IFIRST(header); !IS_LAST_ENTRY(entry); |
|
entry = EXT4_XATTR_NEXT(entry)) |
|
if (entry->e_value_inum) |
|
ea_inode_refs++; |
|
} |
|
|
|
if (EXT4_I(inode)->i_file_acl) { |
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) { |
|
ret = PTR_ERR(bh); |
|
bh = NULL; |
|
goto out; |
|
} |
|
|
|
ret = ext4_xattr_check_block(inode, bh); |
|
if (ret) |
|
goto out; |
|
|
|
for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry); |
|
entry = EXT4_XATTR_NEXT(entry)) |
|
if (entry->e_value_inum) |
|
ea_inode_refs++; |
|
} |
|
*usage = ea_inode_refs + 1; |
|
ret = 0; |
|
out: |
|
brelse(iloc.bh); |
|
brelse(bh); |
|
return ret; |
|
} |
|
|
|
static inline size_t round_up_cluster(struct inode *inode, size_t length) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
size_t cluster_size = 1 << (EXT4_SB(sb)->s_cluster_bits + |
|
inode->i_blkbits); |
|
size_t mask = ~(cluster_size - 1); |
|
|
|
return (length + cluster_size - 1) & mask; |
|
} |
|
|
|
static int ext4_xattr_inode_alloc_quota(struct inode *inode, size_t len) |
|
{ |
|
int err; |
|
|
|
err = dquot_alloc_inode(inode); |
|
if (err) |
|
return err; |
|
err = dquot_alloc_space_nodirty(inode, round_up_cluster(inode, len)); |
|
if (err) |
|
dquot_free_inode(inode); |
|
return err; |
|
} |
|
|
|
static void ext4_xattr_inode_free_quota(struct inode *parent, |
|
struct inode *ea_inode, |
|
size_t len) |
|
{ |
|
if (ea_inode && |
|
ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE)) |
|
return; |
|
dquot_free_space_nodirty(parent, round_up_cluster(parent, len)); |
|
dquot_free_inode(parent); |
|
} |
|
|
|
int __ext4_xattr_set_credits(struct super_block *sb, struct inode *inode, |
|
struct buffer_head *block_bh, size_t value_len, |
|
bool is_create) |
|
{ |
|
int credits; |
|
int blocks; |
|
|
|
/* |
|
* 1) Owner inode update |
|
* 2) Ref count update on old xattr block |
|
* 3) new xattr block |
|
* 4) block bitmap update for new xattr block |
|
* 5) group descriptor for new xattr block |
|
* 6) block bitmap update for old xattr block |
|
* 7) group descriptor for old block |
|
* |
|
* 6 & 7 can happen if we have two racing threads T_a and T_b |
|
* which are each trying to set an xattr on inodes I_a and I_b |
|
* which were both initially sharing an xattr block. |
|
*/ |
|
credits = 7; |
|
|
|
/* Quota updates. */ |
|
credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(sb); |
|
|
|
/* |
|
* In case of inline data, we may push out the data to a block, |
|
* so we need to reserve credits for this eventuality |
|
*/ |
|
if (inode && ext4_has_inline_data(inode)) |
|
credits += ext4_writepage_trans_blocks(inode) + 1; |
|
|
|
/* We are done if ea_inode feature is not enabled. */ |
|
if (!ext4_has_feature_ea_inode(sb)) |
|
return credits; |
|
|
|
/* New ea_inode, inode map, block bitmap, group descriptor. */ |
|
credits += 4; |
|
|
|
/* Data blocks. */ |
|
blocks = (value_len + sb->s_blocksize - 1) >> sb->s_blocksize_bits; |
|
|
|
/* Indirection block or one level of extent tree. */ |
|
blocks += 1; |
|
|
|
/* Block bitmap and group descriptor updates for each block. */ |
|
credits += blocks * 2; |
|
|
|
/* Blocks themselves. */ |
|
credits += blocks; |
|
|
|
if (!is_create) { |
|
/* Dereference ea_inode holding old xattr value. |
|
* Old ea_inode, inode map, block bitmap, group descriptor. |
|
*/ |
|
credits += 4; |
|
|
|
/* Data blocks for old ea_inode. */ |
|
blocks = XATTR_SIZE_MAX >> sb->s_blocksize_bits; |
|
|
|
/* Indirection block or one level of extent tree for old |
|
* ea_inode. |
|
*/ |
|
blocks += 1; |
|
|
|
/* Block bitmap and group descriptor updates for each block. */ |
|
credits += blocks * 2; |
|
} |
|
|
|
/* We may need to clone the existing xattr block in which case we need |
|
* to increment ref counts for existing ea_inodes referenced by it. |
|
*/ |
|
if (block_bh) { |
|
struct ext4_xattr_entry *entry = BFIRST(block_bh); |
|
|
|
for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) |
|
if (entry->e_value_inum) |
|
/* Ref count update on ea_inode. */ |
|
credits += 1; |
|
} |
|
return credits; |
|
} |
|
|
|
static int ext4_xattr_inode_update_ref(handle_t *handle, struct inode *ea_inode, |
|
int ref_change) |
|
{ |
|
struct mb_cache *ea_inode_cache = EA_INODE_CACHE(ea_inode); |
|
struct ext4_iloc iloc; |
|
s64 ref_count; |
|
u32 hash; |
|
int ret; |
|
|
|
inode_lock(ea_inode); |
|
|
|
ret = ext4_reserve_inode_write(handle, ea_inode, &iloc); |
|
if (ret) |
|
goto out; |
|
|
|
ref_count = ext4_xattr_inode_get_ref(ea_inode); |
|
ref_count += ref_change; |
|
ext4_xattr_inode_set_ref(ea_inode, ref_count); |
|
|
|
if (ref_change > 0) { |
|
WARN_ONCE(ref_count <= 0, "EA inode %lu ref_count=%lld", |
|
ea_inode->i_ino, ref_count); |
|
|
|
if (ref_count == 1) { |
|
WARN_ONCE(ea_inode->i_nlink, "EA inode %lu i_nlink=%u", |
|
ea_inode->i_ino, ea_inode->i_nlink); |
|
|
|
set_nlink(ea_inode, 1); |
|
ext4_orphan_del(handle, ea_inode); |
|
|
|
if (ea_inode_cache) { |
|
hash = ext4_xattr_inode_get_hash(ea_inode); |
|
mb_cache_entry_create(ea_inode_cache, |
|
GFP_NOFS, hash, |
|
ea_inode->i_ino, |
|
true /* reusable */); |
|
} |
|
} |
|
} else { |
|
WARN_ONCE(ref_count < 0, "EA inode %lu ref_count=%lld", |
|
ea_inode->i_ino, ref_count); |
|
|
|
if (ref_count == 0) { |
|
WARN_ONCE(ea_inode->i_nlink != 1, |
|
"EA inode %lu i_nlink=%u", |
|
ea_inode->i_ino, ea_inode->i_nlink); |
|
|
|
clear_nlink(ea_inode); |
|
ext4_orphan_add(handle, ea_inode); |
|
|
|
if (ea_inode_cache) { |
|
hash = ext4_xattr_inode_get_hash(ea_inode); |
|
mb_cache_entry_delete(ea_inode_cache, hash, |
|
ea_inode->i_ino); |
|
} |
|
} |
|
} |
|
|
|
ret = ext4_mark_iloc_dirty(handle, ea_inode, &iloc); |
|
if (ret) |
|
ext4_warning_inode(ea_inode, |
|
"ext4_mark_iloc_dirty() failed ret=%d", ret); |
|
out: |
|
inode_unlock(ea_inode); |
|
return ret; |
|
} |
|
|
|
static int ext4_xattr_inode_inc_ref(handle_t *handle, struct inode *ea_inode) |
|
{ |
|
return ext4_xattr_inode_update_ref(handle, ea_inode, 1); |
|
} |
|
|
|
static int ext4_xattr_inode_dec_ref(handle_t *handle, struct inode *ea_inode) |
|
{ |
|
return ext4_xattr_inode_update_ref(handle, ea_inode, -1); |
|
} |
|
|
|
static int ext4_xattr_inode_inc_ref_all(handle_t *handle, struct inode *parent, |
|
struct ext4_xattr_entry *first) |
|
{ |
|
struct inode *ea_inode; |
|
struct ext4_xattr_entry *entry; |
|
struct ext4_xattr_entry *failed_entry; |
|
unsigned int ea_ino; |
|
int err, saved_err; |
|
|
|
for (entry = first; !IS_LAST_ENTRY(entry); |
|
entry = EXT4_XATTR_NEXT(entry)) { |
|
if (!entry->e_value_inum) |
|
continue; |
|
ea_ino = le32_to_cpu(entry->e_value_inum); |
|
err = ext4_xattr_inode_iget(parent, ea_ino, |
|
le32_to_cpu(entry->e_hash), |
|
&ea_inode); |
|
if (err) |
|
goto cleanup; |
|
err = ext4_xattr_inode_inc_ref(handle, ea_inode); |
|
if (err) { |
|
ext4_warning_inode(ea_inode, "inc ref error %d", err); |
|
iput(ea_inode); |
|
goto cleanup; |
|
} |
|
iput(ea_inode); |
|
} |
|
return 0; |
|
|
|
cleanup: |
|
saved_err = err; |
|
failed_entry = entry; |
|
|
|
for (entry = first; entry != failed_entry; |
|
entry = EXT4_XATTR_NEXT(entry)) { |
|
if (!entry->e_value_inum) |
|
continue; |
|
ea_ino = le32_to_cpu(entry->e_value_inum); |
|
err = ext4_xattr_inode_iget(parent, ea_ino, |
|
le32_to_cpu(entry->e_hash), |
|
&ea_inode); |
|
if (err) { |
|
ext4_warning(parent->i_sb, |
|
"cleanup ea_ino %u iget error %d", ea_ino, |
|
err); |
|
continue; |
|
} |
|
err = ext4_xattr_inode_dec_ref(handle, ea_inode); |
|
if (err) |
|
ext4_warning_inode(ea_inode, "cleanup dec ref error %d", |
|
err); |
|
iput(ea_inode); |
|
} |
|
return saved_err; |
|
} |
|
|
|
static int ext4_xattr_restart_fn(handle_t *handle, struct inode *inode, |
|
struct buffer_head *bh, bool block_csum, bool dirty) |
|
{ |
|
int error; |
|
|
|
if (bh && dirty) { |
|
if (block_csum) |
|
ext4_xattr_block_csum_set(inode, bh); |
|
error = ext4_handle_dirty_metadata(handle, NULL, bh); |
|
if (error) { |
|
ext4_warning(inode->i_sb, "Handle metadata (error %d)", |
|
error); |
|
return error; |
|
} |
|
} |
|
return 0; |
|
} |
|
|
|
static void |
|
ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent, |
|
struct buffer_head *bh, |
|
struct ext4_xattr_entry *first, bool block_csum, |
|
struct ext4_xattr_inode_array **ea_inode_array, |
|
int extra_credits, bool skip_quota) |
|
{ |
|
struct inode *ea_inode; |
|
struct ext4_xattr_entry *entry; |
|
bool dirty = false; |
|
unsigned int ea_ino; |
|
int err; |
|
int credits; |
|
|
|
/* One credit for dec ref on ea_inode, one for orphan list addition, */ |
|
credits = 2 + extra_credits; |
|
|
|
for (entry = first; !IS_LAST_ENTRY(entry); |
|
entry = EXT4_XATTR_NEXT(entry)) { |
|
if (!entry->e_value_inum) |
|
continue; |
|
ea_ino = le32_to_cpu(entry->e_value_inum); |
|
err = ext4_xattr_inode_iget(parent, ea_ino, |
|
le32_to_cpu(entry->e_hash), |
|
&ea_inode); |
|
if (err) |
|
continue; |
|
|
|
err = ext4_expand_inode_array(ea_inode_array, ea_inode); |
|
if (err) { |
|
ext4_warning_inode(ea_inode, |
|
"Expand inode array err=%d", err); |
|
iput(ea_inode); |
|
continue; |
|
} |
|
|
|
err = ext4_journal_ensure_credits_fn(handle, credits, credits, |
|
ext4_free_metadata_revoke_credits(parent->i_sb, 1), |
|
ext4_xattr_restart_fn(handle, parent, bh, block_csum, |
|
dirty)); |
|
if (err < 0) { |
|
ext4_warning_inode(ea_inode, "Ensure credits err=%d", |
|
err); |
|
continue; |
|
} |
|
if (err > 0) { |
|
err = ext4_journal_get_write_access(handle, bh); |
|
if (err) { |
|
ext4_warning_inode(ea_inode, |
|
"Re-get write access err=%d", |
|
err); |
|
continue; |
|
} |
|
} |
|
|
|
err = ext4_xattr_inode_dec_ref(handle, ea_inode); |
|
if (err) { |
|
ext4_warning_inode(ea_inode, "ea_inode dec ref err=%d", |
|
err); |
|
continue; |
|
} |
|
|
|
if (!skip_quota) |
|
ext4_xattr_inode_free_quota(parent, ea_inode, |
|
le32_to_cpu(entry->e_value_size)); |
|
|
|
/* |
|
* Forget about ea_inode within the same transaction that |
|
* decrements the ref count. This avoids duplicate decrements in |
|
* case the rest of the work spills over to subsequent |
|
* transactions. |
|
*/ |
|
entry->e_value_inum = 0; |
|
entry->e_value_size = 0; |
|
|
|
dirty = true; |
|
} |
|
|
|
if (dirty) { |
|
/* |
|
* Note that we are deliberately skipping csum calculation for |
|
* the final update because we do not expect any journal |
|
* restarts until xattr block is freed. |
|
*/ |
|
|
|
err = ext4_handle_dirty_metadata(handle, NULL, bh); |
|
if (err) |
|
ext4_warning_inode(parent, |
|
"handle dirty metadata err=%d", err); |
|
} |
|
} |
|
|
|
/* |
|
* Release the xattr block BH: If the reference count is > 1, decrement it; |
|
* otherwise free the block. |
|
*/ |
|
static void |
|
ext4_xattr_release_block(handle_t *handle, struct inode *inode, |
|
struct buffer_head *bh, |
|
struct ext4_xattr_inode_array **ea_inode_array, |
|
int extra_credits) |
|
{ |
|
struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); |
|
u32 hash, ref; |
|
int error = 0; |
|
|
|
BUFFER_TRACE(bh, "get_write_access"); |
|
error = ext4_journal_get_write_access(handle, bh); |
|
if (error) |
|
goto out; |
|
|
|
lock_buffer(bh); |
|
hash = le32_to_cpu(BHDR(bh)->h_hash); |
|
ref = le32_to_cpu(BHDR(bh)->h_refcount); |
|
if (ref == 1) { |
|
ea_bdebug(bh, "refcount now=0; freeing"); |
|
/* |
|
* This must happen under buffer lock for |
|
* ext4_xattr_block_set() to reliably detect freed block |
|
*/ |
|
if (ea_block_cache) |
|
mb_cache_entry_delete(ea_block_cache, hash, |
|
bh->b_blocknr); |
|
get_bh(bh); |
|
unlock_buffer(bh); |
|
|
|
if (ext4_has_feature_ea_inode(inode->i_sb)) |
|
ext4_xattr_inode_dec_ref_all(handle, inode, bh, |
|
BFIRST(bh), |
|
true /* block_csum */, |
|
ea_inode_array, |
|
extra_credits, |
|
true /* skip_quota */); |
|
ext4_free_blocks(handle, inode, bh, 0, 1, |
|
EXT4_FREE_BLOCKS_METADATA | |
|
EXT4_FREE_BLOCKS_FORGET); |
|
} else { |
|
ref--; |
|
BHDR(bh)->h_refcount = cpu_to_le32(ref); |
|
if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { |
|
struct mb_cache_entry *ce; |
|
|
|
if (ea_block_cache) { |
|
ce = mb_cache_entry_get(ea_block_cache, hash, |
|
bh->b_blocknr); |
|
if (ce) { |
|
ce->e_reusable = 1; |
|
mb_cache_entry_put(ea_block_cache, ce); |
|
} |
|
} |
|
} |
|
|
|
ext4_xattr_block_csum_set(inode, bh); |
|
/* |
|
* Beware of this ugliness: Releasing of xattr block references |
|
* from different inodes can race and so we have to protect |
|
* from a race where someone else frees the block (and releases |
|
* its journal_head) before we are done dirtying the buffer. In |
|
* nojournal mode this race is harmless and we actually cannot |
|
* call ext4_handle_dirty_metadata() with locked buffer as |
|
* that function can call sync_dirty_buffer() so for that case |
|
* we handle the dirtying after unlocking the buffer. |
|
*/ |
|
if (ext4_handle_valid(handle)) |
|
error = ext4_handle_dirty_metadata(handle, inode, bh); |
|
unlock_buffer(bh); |
|
if (!ext4_handle_valid(handle)) |
|
error = ext4_handle_dirty_metadata(handle, inode, bh); |
|
if (IS_SYNC(inode)) |
|
ext4_handle_sync(handle); |
|
dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); |
|
ea_bdebug(bh, "refcount now=%d; releasing", |
|
le32_to_cpu(BHDR(bh)->h_refcount)); |
|
} |
|
out: |
|
ext4_std_error(inode->i_sb, error); |
|
return; |
|
} |
|
|
|
/* |
|
* Find the available free space for EAs. This also returns the total number of |
|
* bytes used by EA entries. |
|
*/ |
|
static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, |
|
size_t *min_offs, void *base, int *total) |
|
{ |
|
for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
|
if (!last->e_value_inum && last->e_value_size) { |
|
size_t offs = le16_to_cpu(last->e_value_offs); |
|
if (offs < *min_offs) |
|
*min_offs = offs; |
|
} |
|
if (total) |
|
*total += EXT4_XATTR_LEN(last->e_name_len); |
|
} |
|
return (*min_offs - ((void *)last - base) - sizeof(__u32)); |
|
} |
|
|
|
/* |
|
* Write the value of the EA in an inode. |
|
*/ |
|
static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, |
|
const void *buf, int bufsize) |
|
{ |
|
struct buffer_head *bh = NULL; |
|
unsigned long block = 0; |
|
int blocksize = ea_inode->i_sb->s_blocksize; |
|
int max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits; |
|
int csize, wsize = 0; |
|
int ret = 0, ret2 = 0; |
|
int retries = 0; |
|
|
|
retry: |
|
while (ret >= 0 && ret < max_blocks) { |
|
struct ext4_map_blocks map; |
|
map.m_lblk = block += ret; |
|
map.m_len = max_blocks -= ret; |
|
|
|
ret = ext4_map_blocks(handle, ea_inode, &map, |
|
EXT4_GET_BLOCKS_CREATE); |
|
if (ret <= 0) { |
|
ext4_mark_inode_dirty(handle, ea_inode); |
|
if (ret == -ENOSPC && |
|
ext4_should_retry_alloc(ea_inode->i_sb, &retries)) { |
|
ret = 0; |
|
goto retry; |
|
} |
|
break; |
|
} |
|
} |
|
|
|
if (ret < 0) |
|
return ret; |
|
|
|
block = 0; |
|
while (wsize < bufsize) { |
|
brelse(bh); |
|
csize = (bufsize - wsize) > blocksize ? blocksize : |
|
bufsize - wsize; |
|
bh = ext4_getblk(handle, ea_inode, block, 0); |
|
if (IS_ERR(bh)) |
|
return PTR_ERR(bh); |
|
if (!bh) { |
|
WARN_ON_ONCE(1); |
|
EXT4_ERROR_INODE(ea_inode, |
|
"ext4_getblk() return bh = NULL"); |
|
return -EFSCORRUPTED; |
|
} |
|
ret = ext4_journal_get_write_access(handle, bh); |
|
if (ret) |
|
goto out; |
|
|
|
memcpy(bh->b_data, buf, csize); |
|
set_buffer_uptodate(bh); |
|
ext4_handle_dirty_metadata(handle, ea_inode, bh); |
|
|
|
buf += csize; |
|
wsize += csize; |
|
block += 1; |
|
} |
|
|
|
inode_lock(ea_inode); |
|
i_size_write(ea_inode, wsize); |
|
ext4_update_i_disksize(ea_inode, wsize); |
|
inode_unlock(ea_inode); |
|
|
|
ret2 = ext4_mark_inode_dirty(handle, ea_inode); |
|
if (unlikely(ret2 && !ret)) |
|
ret = ret2; |
|
|
|
out: |
|
brelse(bh); |
|
|
|
return ret; |
|
} |
|
|
|
/* |
|
* Create an inode to store the value of a large EA. |
|
*/ |
|
static struct inode *ext4_xattr_inode_create(handle_t *handle, |
|
struct inode *inode, u32 hash) |
|
{ |
|
struct inode *ea_inode = NULL; |
|
uid_t owner[2] = { i_uid_read(inode), i_gid_read(inode) }; |
|
int err; |
|
|
|
/* |
|
* Let the next inode be the goal, so we try and allocate the EA inode |
|
* in the same group, or nearby one. |
|
*/ |
|
ea_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode, |
|
S_IFREG | 0600, NULL, inode->i_ino + 1, owner, |
|
EXT4_EA_INODE_FL); |
|
if (!IS_ERR(ea_inode)) { |
|
ea_inode->i_op = &ext4_file_inode_operations; |
|
ea_inode->i_fop = &ext4_file_operations; |
|
ext4_set_aops(ea_inode); |
|
ext4_xattr_inode_set_class(ea_inode); |
|
unlock_new_inode(ea_inode); |
|
ext4_xattr_inode_set_ref(ea_inode, 1); |
|
ext4_xattr_inode_set_hash(ea_inode, hash); |
|
err = ext4_mark_inode_dirty(handle, ea_inode); |
|
if (!err) |
|
err = ext4_inode_attach_jinode(ea_inode); |
|
if (err) { |
|
iput(ea_inode); |
|
return ERR_PTR(err); |
|
} |
|
|
|
/* |
|
* Xattr inodes are shared therefore quota charging is performed |
|
* at a higher level. |
|
*/ |
|
dquot_free_inode(ea_inode); |
|
dquot_drop(ea_inode); |
|
inode_lock(ea_inode); |
|
ea_inode->i_flags |= S_NOQUOTA; |
|
inode_unlock(ea_inode); |
|
} |
|
|
|
return ea_inode; |
|
} |
|
|
|
static struct inode * |
|
ext4_xattr_inode_cache_find(struct inode *inode, const void *value, |
|
size_t value_len, u32 hash) |
|
{ |
|
struct inode *ea_inode; |
|
struct mb_cache_entry *ce; |
|
struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); |
|
void *ea_data; |
|
|
|
if (!ea_inode_cache) |
|
return NULL; |
|
|
|
ce = mb_cache_entry_find_first(ea_inode_cache, hash); |
|
if (!ce) |
|
return NULL; |
|
|
|
WARN_ON_ONCE(ext4_handle_valid(journal_current_handle()) && |
|
!(current->flags & PF_MEMALLOC_NOFS)); |
|
|
|
ea_data = kvmalloc(value_len, GFP_KERNEL); |
|
if (!ea_data) { |
|
mb_cache_entry_put(ea_inode_cache, ce); |
|
return NULL; |
|
} |
|
|
|
while (ce) { |
|
ea_inode = ext4_iget(inode->i_sb, ce->e_value, |
|
EXT4_IGET_NORMAL); |
|
if (!IS_ERR(ea_inode) && |
|
!is_bad_inode(ea_inode) && |
|
(EXT4_I(ea_inode)->i_flags & EXT4_EA_INODE_FL) && |
|
i_size_read(ea_inode) == value_len && |
|
!ext4_xattr_inode_read(ea_inode, ea_data, value_len) && |
|
!ext4_xattr_inode_verify_hashes(ea_inode, NULL, ea_data, |
|
value_len) && |
|
!memcmp(value, ea_data, value_len)) { |
|
mb_cache_entry_touch(ea_inode_cache, ce); |
|
mb_cache_entry_put(ea_inode_cache, ce); |
|
kvfree(ea_data); |
|
return ea_inode; |
|
} |
|
|
|
if (!IS_ERR(ea_inode)) |
|
iput(ea_inode); |
|
ce = mb_cache_entry_find_next(ea_inode_cache, ce); |
|
} |
|
kvfree(ea_data); |
|
return NULL; |
|
} |
|
|
|
/* |
|
* Add value of the EA in an inode. |
|
*/ |
|
static int ext4_xattr_inode_lookup_create(handle_t *handle, struct inode *inode, |
|
const void *value, size_t value_len, |
|
struct inode **ret_inode) |
|
{ |
|
struct inode *ea_inode; |
|
u32 hash; |
|
int err; |
|
|
|
hash = ext4_xattr_inode_hash(EXT4_SB(inode->i_sb), value, value_len); |
|
ea_inode = ext4_xattr_inode_cache_find(inode, value, value_len, hash); |
|
if (ea_inode) { |
|
err = ext4_xattr_inode_inc_ref(handle, ea_inode); |
|
if (err) { |
|
iput(ea_inode); |
|
return err; |
|
} |
|
|
|
*ret_inode = ea_inode; |
|
return 0; |
|
} |
|
|
|
/* Create an inode for the EA value */ |
|
ea_inode = ext4_xattr_inode_create(handle, inode, hash); |
|
if (IS_ERR(ea_inode)) |
|
return PTR_ERR(ea_inode); |
|
|
|
err = ext4_xattr_inode_write(handle, ea_inode, value, value_len); |
|
if (err) { |
|
ext4_xattr_inode_dec_ref(handle, ea_inode); |
|
iput(ea_inode); |
|
return err; |
|
} |
|
|
|
if (EA_INODE_CACHE(inode)) |
|
mb_cache_entry_create(EA_INODE_CACHE(inode), GFP_NOFS, hash, |
|
ea_inode->i_ino, true /* reusable */); |
|
|
|
*ret_inode = ea_inode; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Reserve min(block_size/8, 1024) bytes for xattr entries/names if ea_inode |
|
* feature is enabled. |
|
*/ |
|
#define EXT4_XATTR_BLOCK_RESERVE(inode) min(i_blocksize(inode)/8, 1024U) |
|
|
|
static int ext4_xattr_set_entry(struct ext4_xattr_info *i, |
|
struct ext4_xattr_search *s, |
|
handle_t *handle, struct inode *inode, |
|
bool is_block) |
|
{ |
|
struct ext4_xattr_entry *last, *next; |
|
struct ext4_xattr_entry *here = s->here; |
|
size_t min_offs = s->end - s->base, name_len = strlen(i->name); |
|
int in_inode = i->in_inode; |
|
struct inode *old_ea_inode = NULL; |
|
struct inode *new_ea_inode = NULL; |
|
size_t old_size, new_size; |
|
int ret; |
|
|
|
/* Space used by old and new values. */ |
|
old_size = (!s->not_found && !here->e_value_inum) ? |
|
EXT4_XATTR_SIZE(le32_to_cpu(here->e_value_size)) : 0; |
|
new_size = (i->value && !in_inode) ? EXT4_XATTR_SIZE(i->value_len) : 0; |
|
|
|
/* |
|
* Optimization for the simple case when old and new values have the |
|
* same padded sizes. Not applicable if external inodes are involved. |
|
*/ |
|
if (new_size && new_size == old_size) { |
|
size_t offs = le16_to_cpu(here->e_value_offs); |
|
void *val = s->base + offs; |
|
|
|
here->e_value_size = cpu_to_le32(i->value_len); |
|
if (i->value == EXT4_ZERO_XATTR_VALUE) { |
|
memset(val, 0, new_size); |
|
} else { |
|
memcpy(val, i->value, i->value_len); |
|
/* Clear padding bytes. */ |
|
memset(val + i->value_len, 0, new_size - i->value_len); |
|
} |
|
goto update_hash; |
|
} |
|
|
|
/* Compute min_offs and last. */ |
|
last = s->first; |
|
for (; !IS_LAST_ENTRY(last); last = next) { |
|
next = EXT4_XATTR_NEXT(last); |
|
if ((void *)next >= s->end) { |
|
EXT4_ERROR_INODE(inode, "corrupted xattr entries"); |
|
ret = -EFSCORRUPTED; |
|
goto out; |
|
} |
|
if (!last->e_value_inum && last->e_value_size) { |
|
size_t offs = le16_to_cpu(last->e_value_offs); |
|
if (offs < min_offs) |
|
min_offs = offs; |
|
} |
|
} |
|
|
|
/* Check whether we have enough space. */ |
|
if (i->value) { |
|
size_t free; |
|
|
|
free = min_offs - ((void *)last - s->base) - sizeof(__u32); |
|
if (!s->not_found) |
|
free += EXT4_XATTR_LEN(name_len) + old_size; |
|
|
|
if (free < EXT4_XATTR_LEN(name_len) + new_size) { |
|
ret = -ENOSPC; |
|
goto out; |
|
} |
|
|
|
/* |
|
* If storing the value in an external inode is an option, |
|
* reserve space for xattr entries/names in the external |
|
* attribute block so that a long value does not occupy the |
|
* whole space and prevent further entries being added. |
|
*/ |
|
if (ext4_has_feature_ea_inode(inode->i_sb) && |
|
new_size && is_block && |
|
(min_offs + old_size - new_size) < |
|
EXT4_XATTR_BLOCK_RESERVE(inode)) { |
|
ret = -ENOSPC; |
|
goto out; |
|
} |
|
} |
|
|
|
/* |
|
* Getting access to old and new ea inodes is subject to failures. |
|
* Finish that work before doing any modifications to the xattr data. |
|
*/ |
|
if (!s->not_found && here->e_value_inum) { |
|
ret = ext4_xattr_inode_iget(inode, |
|
le32_to_cpu(here->e_value_inum), |
|
le32_to_cpu(here->e_hash), |
|
&old_ea_inode); |
|
if (ret) { |
|
old_ea_inode = NULL; |
|
goto out; |
|
} |
|
} |
|
if (i->value && in_inode) { |
|
WARN_ON_ONCE(!i->value_len); |
|
|
|
ret = ext4_xattr_inode_alloc_quota(inode, i->value_len); |
|
if (ret) |
|
goto out; |
|
|
|
ret = ext4_xattr_inode_lookup_create(handle, inode, i->value, |
|
i->value_len, |
|
&new_ea_inode); |
|
if (ret) { |
|
new_ea_inode = NULL; |
|
ext4_xattr_inode_free_quota(inode, NULL, i->value_len); |
|
goto out; |
|
} |
|
} |
|
|
|
if (old_ea_inode) { |
|
/* We are ready to release ref count on the old_ea_inode. */ |
|
ret = ext4_xattr_inode_dec_ref(handle, old_ea_inode); |
|
if (ret) { |
|
/* Release newly required ref count on new_ea_inode. */ |
|
if (new_ea_inode) { |
|
int err; |
|
|
|
err = ext4_xattr_inode_dec_ref(handle, |
|
new_ea_inode); |
|
if (err) |
|
ext4_warning_inode(new_ea_inode, |
|
"dec ref new_ea_inode err=%d", |
|
err); |
|
ext4_xattr_inode_free_quota(inode, new_ea_inode, |
|
i->value_len); |
|
} |
|
goto out; |
|
} |
|
|
|
ext4_xattr_inode_free_quota(inode, old_ea_inode, |
|
le32_to_cpu(here->e_value_size)); |
|
} |
|
|
|
/* No failures allowed past this point. */ |
|
|
|
if (!s->not_found && here->e_value_size && !here->e_value_inum) { |
|
/* Remove the old value. */ |
|
void *first_val = s->base + min_offs; |
|
size_t offs = le16_to_cpu(here->e_value_offs); |
|
void *val = s->base + offs; |
|
|
|
memmove(first_val + old_size, first_val, val - first_val); |
|
memset(first_val, 0, old_size); |
|
min_offs += old_size; |
|
|
|
/* Adjust all value offsets. */ |
|
last = s->first; |
|
while (!IS_LAST_ENTRY(last)) { |
|
size_t o = le16_to_cpu(last->e_value_offs); |
|
|
|
if (!last->e_value_inum && |
|
last->e_value_size && o < offs) |
|
last->e_value_offs = cpu_to_le16(o + old_size); |
|
last = EXT4_XATTR_NEXT(last); |
|
} |
|
} |
|
|
|
if (!i->value) { |
|
/* Remove old name. */ |
|
size_t size = EXT4_XATTR_LEN(name_len); |
|
|
|
last = ENTRY((void *)last - size); |
|
memmove(here, (void *)here + size, |
|
(void *)last - (void *)here + sizeof(__u32)); |
|
memset(last, 0, size); |
|
} else if (s->not_found) { |
|
/* Insert new name. */ |
|
size_t size = EXT4_XATTR_LEN(name_len); |
|
size_t rest = (void *)last - (void *)here + sizeof(__u32); |
|
|
|
memmove((void *)here + size, here, rest); |
|
memset(here, 0, size); |
|
here->e_name_index = i->name_index; |
|
here->e_name_len = name_len; |
|
memcpy(here->e_name, i->name, name_len); |
|
} else { |
|
/* This is an update, reset value info. */ |
|
here->e_value_inum = 0; |
|
here->e_value_offs = 0; |
|
here->e_value_size = 0; |
|
} |
|
|
|
if (i->value) { |
|
/* Insert new value. */ |
|
if (in_inode) { |
|
here->e_value_inum = cpu_to_le32(new_ea_inode->i_ino); |
|
} else if (i->value_len) { |
|
void *val = s->base + min_offs - new_size; |
|
|
|
here->e_value_offs = cpu_to_le16(min_offs - new_size); |
|
if (i->value == EXT4_ZERO_XATTR_VALUE) { |
|
memset(val, 0, new_size); |
|
} else { |
|
memcpy(val, i->value, i->value_len); |
|
/* Clear padding bytes. */ |
|
memset(val + i->value_len, 0, |
|
new_size - i->value_len); |
|
} |
|
} |
|
here->e_value_size = cpu_to_le32(i->value_len); |
|
} |
|
|
|
update_hash: |
|
if (i->value) { |
|
__le32 hash = 0; |
|
|
|
/* Entry hash calculation. */ |
|
if (in_inode) { |
|
__le32 crc32c_hash; |
|
|
|
/* |
|
* Feed crc32c hash instead of the raw value for entry |
|
* hash calculation. This is to avoid walking |
|
* potentially long value buffer again. |
|
*/ |
|
crc32c_hash = cpu_to_le32( |
|
ext4_xattr_inode_get_hash(new_ea_inode)); |
|
hash = ext4_xattr_hash_entry(here->e_name, |
|
here->e_name_len, |
|
&crc32c_hash, 1); |
|
} else if (is_block) { |
|
__le32 *value = s->base + le16_to_cpu( |
|
here->e_value_offs); |
|
|
|
hash = ext4_xattr_hash_entry(here->e_name, |
|
here->e_name_len, value, |
|
new_size >> 2); |
|
} |
|
here->e_hash = hash; |
|
} |
|
|
|
if (is_block) |
|
ext4_xattr_rehash((struct ext4_xattr_header *)s->base); |
|
|
|
ret = 0; |
|
out: |
|
iput(old_ea_inode); |
|
iput(new_ea_inode); |
|
return ret; |
|
} |
|
|
|
struct ext4_xattr_block_find { |
|
struct ext4_xattr_search s; |
|
struct buffer_head *bh; |
|
}; |
|
|
|
static int |
|
ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, |
|
struct ext4_xattr_block_find *bs) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
int error; |
|
|
|
ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", |
|
i->name_index, i->name, i->value, (long)i->value_len); |
|
|
|
if (EXT4_I(inode)->i_file_acl) { |
|
/* The inode already has an extended attribute block. */ |
|
bs->bh = ext4_sb_bread(sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bs->bh)) { |
|
error = PTR_ERR(bs->bh); |
|
bs->bh = NULL; |
|
return error; |
|
} |
|
ea_bdebug(bs->bh, "b_count=%d, refcount=%d", |
|
atomic_read(&(bs->bh->b_count)), |
|
le32_to_cpu(BHDR(bs->bh)->h_refcount)); |
|
error = ext4_xattr_check_block(inode, bs->bh); |
|
if (error) |
|
return error; |
|
/* Find the named attribute. */ |
|
bs->s.base = BHDR(bs->bh); |
|
bs->s.first = BFIRST(bs->bh); |
|
bs->s.end = bs->bh->b_data + bs->bh->b_size; |
|
bs->s.here = bs->s.first; |
|
error = xattr_find_entry(inode, &bs->s.here, bs->s.end, |
|
i->name_index, i->name, 1); |
|
if (error && error != -ENODATA) |
|
return error; |
|
bs->s.not_found = error; |
|
} |
|
return 0; |
|
} |
|
|
|
static int |
|
ext4_xattr_block_set(handle_t *handle, struct inode *inode, |
|
struct ext4_xattr_info *i, |
|
struct ext4_xattr_block_find *bs) |
|
{ |
|
struct super_block *sb = inode->i_sb; |
|
struct buffer_head *new_bh = NULL; |
|
struct ext4_xattr_search s_copy = bs->s; |
|
struct ext4_xattr_search *s = &s_copy; |
|
struct mb_cache_entry *ce = NULL; |
|
int error = 0; |
|
struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); |
|
struct inode *ea_inode = NULL, *tmp_inode; |
|
size_t old_ea_inode_quota = 0; |
|
unsigned int ea_ino; |
|
|
|
|
|
#define header(x) ((struct ext4_xattr_header *)(x)) |
|
|
|
if (s->base) { |
|
BUFFER_TRACE(bs->bh, "get_write_access"); |
|
error = ext4_journal_get_write_access(handle, bs->bh); |
|
if (error) |
|
goto cleanup; |
|
lock_buffer(bs->bh); |
|
|
|
if (header(s->base)->h_refcount == cpu_to_le32(1)) { |
|
__u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); |
|
|
|
/* |
|
* This must happen under buffer lock for |
|
* ext4_xattr_block_set() to reliably detect modified |
|
* block |
|
*/ |
|
if (ea_block_cache) |
|
mb_cache_entry_delete(ea_block_cache, hash, |
|
bs->bh->b_blocknr); |
|
ea_bdebug(bs->bh, "modifying in-place"); |
|
error = ext4_xattr_set_entry(i, s, handle, inode, |
|
true /* is_block */); |
|
ext4_xattr_block_csum_set(inode, bs->bh); |
|
unlock_buffer(bs->bh); |
|
if (error == -EFSCORRUPTED) |
|
goto bad_block; |
|
if (!error) |
|
error = ext4_handle_dirty_metadata(handle, |
|
inode, |
|
bs->bh); |
|
if (error) |
|
goto cleanup; |
|
goto inserted; |
|
} else { |
|
int offset = (char *)s->here - bs->bh->b_data; |
|
|
|
unlock_buffer(bs->bh); |
|
ea_bdebug(bs->bh, "cloning"); |
|
s->base = kmalloc(bs->bh->b_size, GFP_NOFS); |
|
error = -ENOMEM; |
|
if (s->base == NULL) |
|
goto cleanup; |
|
memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); |
|
s->first = ENTRY(header(s->base)+1); |
|
header(s->base)->h_refcount = cpu_to_le32(1); |
|
s->here = ENTRY(s->base + offset); |
|
s->end = s->base + bs->bh->b_size; |
|
|
|
/* |
|
* If existing entry points to an xattr inode, we need |
|
* to prevent ext4_xattr_set_entry() from decrementing |
|
* ref count on it because the reference belongs to the |
|
* original block. In this case, make the entry look |
|
* like it has an empty value. |
|
*/ |
|
if (!s->not_found && s->here->e_value_inum) { |
|
ea_ino = le32_to_cpu(s->here->e_value_inum); |
|
error = ext4_xattr_inode_iget(inode, ea_ino, |
|
le32_to_cpu(s->here->e_hash), |
|
&tmp_inode); |
|
if (error) |
|
goto cleanup; |
|
|
|
if (!ext4_test_inode_state(tmp_inode, |
|
EXT4_STATE_LUSTRE_EA_INODE)) { |
|
/* |
|
* Defer quota free call for previous |
|
* inode until success is guaranteed. |
|
*/ |
|
old_ea_inode_quota = le32_to_cpu( |
|
s->here->e_value_size); |
|
} |
|
iput(tmp_inode); |
|
|
|
s->here->e_value_inum = 0; |
|
s->here->e_value_size = 0; |
|
} |
|
} |
|
} else { |
|
/* Allocate a buffer where we construct the new block. */ |
|
s->base = kzalloc(sb->s_blocksize, GFP_NOFS); |
|
error = -ENOMEM; |
|
if (s->base == NULL) |
|
goto cleanup; |
|
header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
|
header(s->base)->h_blocks = cpu_to_le32(1); |
|
header(s->base)->h_refcount = cpu_to_le32(1); |
|
s->first = ENTRY(header(s->base)+1); |
|
s->here = ENTRY(header(s->base)+1); |
|
s->end = s->base + sb->s_blocksize; |
|
} |
|
|
|
error = ext4_xattr_set_entry(i, s, handle, inode, true /* is_block */); |
|
if (error == -EFSCORRUPTED) |
|
goto bad_block; |
|
if (error) |
|
goto cleanup; |
|
|
|
if (i->value && s->here->e_value_inum) { |
|
/* |
|
* A ref count on ea_inode has been taken as part of the call to |
|
* ext4_xattr_set_entry() above. We would like to drop this |
|
* extra ref but we have to wait until the xattr block is |
|
* initialized and has its own ref count on the ea_inode. |
|
*/ |
|
ea_ino = le32_to_cpu(s->here->e_value_inum); |
|
error = ext4_xattr_inode_iget(inode, ea_ino, |
|
le32_to_cpu(s->here->e_hash), |
|
&ea_inode); |
|
if (error) { |
|
ea_inode = NULL; |
|
goto cleanup; |
|
} |
|
} |
|
|
|
inserted: |
|
if (!IS_LAST_ENTRY(s->first)) { |
|
new_bh = ext4_xattr_block_cache_find(inode, header(s->base), |
|
&ce); |
|
if (new_bh) { |
|
/* We found an identical block in the cache. */ |
|
if (new_bh == bs->bh) |
|
ea_bdebug(new_bh, "keeping"); |
|
else { |
|
u32 ref; |
|
|
|
WARN_ON_ONCE(dquot_initialize_needed(inode)); |
|
|
|
/* The old block is released after updating |
|
the inode. */ |
|
error = dquot_alloc_block(inode, |
|
EXT4_C2B(EXT4_SB(sb), 1)); |
|
if (error) |
|
goto cleanup; |
|
BUFFER_TRACE(new_bh, "get_write_access"); |
|
error = ext4_journal_get_write_access(handle, |
|
new_bh); |
|
if (error) |
|
goto cleanup_dquot; |
|
lock_buffer(new_bh); |
|
/* |
|
* We have to be careful about races with |
|
* freeing, rehashing or adding references to |
|
* xattr block. Once we hold buffer lock xattr |
|
* block's state is stable so we can check |
|
* whether the block got freed / rehashed or |
|
* not. Since we unhash mbcache entry under |
|
* buffer lock when freeing / rehashing xattr |
|
* block, checking whether entry is still |
|
* hashed is reliable. Same rules hold for |
|
* e_reusable handling. |
|
*/ |
|
if (hlist_bl_unhashed(&ce->e_hash_list) || |
|
!ce->e_reusable) { |
|
/* |
|
* Undo everything and check mbcache |
|
* again. |
|
*/ |
|
unlock_buffer(new_bh); |
|
dquot_free_block(inode, |
|
EXT4_C2B(EXT4_SB(sb), |
|
1)); |
|
brelse(new_bh); |
|
mb_cache_entry_put(ea_block_cache, ce); |
|
ce = NULL; |
|
new_bh = NULL; |
|
goto inserted; |
|
} |
|
ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; |
|
BHDR(new_bh)->h_refcount = cpu_to_le32(ref); |
|
if (ref >= EXT4_XATTR_REFCOUNT_MAX) |
|
ce->e_reusable = 0; |
|
ea_bdebug(new_bh, "reusing; refcount now=%d", |
|
ref); |
|
ext4_xattr_block_csum_set(inode, new_bh); |
|
unlock_buffer(new_bh); |
|
error = ext4_handle_dirty_metadata(handle, |
|
inode, |
|
new_bh); |
|
if (error) |
|
goto cleanup_dquot; |
|
} |
|
mb_cache_entry_touch(ea_block_cache, ce); |
|
mb_cache_entry_put(ea_block_cache, ce); |
|
ce = NULL; |
|
} else if (bs->bh && s->base == bs->bh->b_data) { |
|
/* We were modifying this block in-place. */ |
|
ea_bdebug(bs->bh, "keeping this block"); |
|
ext4_xattr_block_cache_insert(ea_block_cache, bs->bh); |
|
new_bh = bs->bh; |
|
get_bh(new_bh); |
|
} else { |
|
/* We need to allocate a new block */ |
|
ext4_fsblk_t goal, block; |
|
|
|
WARN_ON_ONCE(dquot_initialize_needed(inode)); |
|
|
|
goal = ext4_group_first_block_no(sb, |
|
EXT4_I(inode)->i_block_group); |
|
|
|
/* non-extent files can't have physical blocks past 2^32 */ |
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
|
goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; |
|
|
|
block = ext4_new_meta_blocks(handle, inode, goal, 0, |
|
NULL, &error); |
|
if (error) |
|
goto cleanup; |
|
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) |
|
BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); |
|
|
|
ea_idebug(inode, "creating block %llu", |
|
(unsigned long long)block); |
|
|
|
new_bh = sb_getblk(sb, block); |
|
if (unlikely(!new_bh)) { |
|
error = -ENOMEM; |
|
getblk_failed: |
|
ext4_free_blocks(handle, inode, NULL, block, 1, |
|
EXT4_FREE_BLOCKS_METADATA); |
|
goto cleanup; |
|
} |
|
error = ext4_xattr_inode_inc_ref_all(handle, inode, |
|
ENTRY(header(s->base)+1)); |
|
if (error) |
|
goto getblk_failed; |
|
if (ea_inode) { |
|
/* Drop the extra ref on ea_inode. */ |
|
error = ext4_xattr_inode_dec_ref(handle, |
|
ea_inode); |
|
if (error) |
|
ext4_warning_inode(ea_inode, |
|
"dec ref error=%d", |
|
error); |
|
iput(ea_inode); |
|
ea_inode = NULL; |
|
} |
|
|
|
lock_buffer(new_bh); |
|
error = ext4_journal_get_create_access(handle, new_bh); |
|
if (error) { |
|
unlock_buffer(new_bh); |
|
error = -EIO; |
|
goto getblk_failed; |
|
} |
|
memcpy(new_bh->b_data, s->base, new_bh->b_size); |
|
ext4_xattr_block_csum_set(inode, new_bh); |
|
set_buffer_uptodate(new_bh); |
|
unlock_buffer(new_bh); |
|
ext4_xattr_block_cache_insert(ea_block_cache, new_bh); |
|
error = ext4_handle_dirty_metadata(handle, inode, |
|
new_bh); |
|
if (error) |
|
goto cleanup; |
|
} |
|
} |
|
|
|
if (old_ea_inode_quota) |
|
ext4_xattr_inode_free_quota(inode, NULL, old_ea_inode_quota); |
|
|
|
/* Update the inode. */ |
|
EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; |
|
|
|
/* Drop the previous xattr block. */ |
|
if (bs->bh && bs->bh != new_bh) { |
|
struct ext4_xattr_inode_array *ea_inode_array = NULL; |
|
|
|
ext4_xattr_release_block(handle, inode, bs->bh, |
|
&ea_inode_array, |
|
0 /* extra_credits */); |
|
ext4_xattr_inode_array_free(ea_inode_array); |
|
} |
|
error = 0; |
|
|
|
cleanup: |
|
if (ea_inode) { |
|
int error2; |
|
|
|
error2 = ext4_xattr_inode_dec_ref(handle, ea_inode); |
|
if (error2) |
|
ext4_warning_inode(ea_inode, "dec ref error=%d", |
|
error2); |
|
|
|
/* If there was an error, revert the quota charge. */ |
|
if (error) |
|
ext4_xattr_inode_free_quota(inode, ea_inode, |
|
i_size_read(ea_inode)); |
|
iput(ea_inode); |
|
} |
|
if (ce) |
|
mb_cache_entry_put(ea_block_cache, ce); |
|
brelse(new_bh); |
|
if (!(bs->bh && s->base == bs->bh->b_data)) |
|
kfree(s->base); |
|
|
|
return error; |
|
|
|
cleanup_dquot: |
|
dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); |
|
goto cleanup; |
|
|
|
bad_block: |
|
EXT4_ERROR_INODE(inode, "bad block %llu", |
|
EXT4_I(inode)->i_file_acl); |
|
goto cleanup; |
|
|
|
#undef header |
|
} |
|
|
|
int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, |
|
struct ext4_xattr_ibody_find *is) |
|
{ |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_inode *raw_inode; |
|
int error; |
|
|
|
if (EXT4_I(inode)->i_extra_isize == 0) |
|
return 0; |
|
raw_inode = ext4_raw_inode(&is->iloc); |
|
header = IHDR(inode, raw_inode); |
|
is->s.base = is->s.first = IFIRST(header); |
|
is->s.here = is->s.first; |
|
is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
|
if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
|
error = xattr_check_inode(inode, header, is->s.end); |
|
if (error) |
|
return error; |
|
/* Find the named attribute. */ |
|
error = xattr_find_entry(inode, &is->s.here, is->s.end, |
|
i->name_index, i->name, 0); |
|
if (error && error != -ENODATA) |
|
return error; |
|
is->s.not_found = error; |
|
} |
|
return 0; |
|
} |
|
|
|
int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, |
|
struct ext4_xattr_info *i, |
|
struct ext4_xattr_ibody_find *is) |
|
{ |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_xattr_search *s = &is->s; |
|
int error; |
|
|
|
if (EXT4_I(inode)->i_extra_isize == 0) |
|
return -ENOSPC; |
|
error = ext4_xattr_set_entry(i, s, handle, inode, false /* is_block */); |
|
if (error) |
|
return error; |
|
header = IHDR(inode, ext4_raw_inode(&is->iloc)); |
|
if (!IS_LAST_ENTRY(s->first)) { |
|
header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); |
|
ext4_set_inode_state(inode, EXT4_STATE_XATTR); |
|
} else { |
|
header->h_magic = cpu_to_le32(0); |
|
ext4_clear_inode_state(inode, EXT4_STATE_XATTR); |
|
} |
|
return 0; |
|
} |
|
|
|
static int ext4_xattr_value_same(struct ext4_xattr_search *s, |
|
struct ext4_xattr_info *i) |
|
{ |
|
void *value; |
|
|
|
/* When e_value_inum is set the value is stored externally. */ |
|
if (s->here->e_value_inum) |
|
return 0; |
|
if (le32_to_cpu(s->here->e_value_size) != i->value_len) |
|
return 0; |
|
value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); |
|
return !memcmp(value, i->value, i->value_len); |
|
} |
|
|
|
static struct buffer_head *ext4_xattr_get_block(struct inode *inode) |
|
{ |
|
struct buffer_head *bh; |
|
int error; |
|
|
|
if (!EXT4_I(inode)->i_file_acl) |
|
return NULL; |
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) |
|
return bh; |
|
error = ext4_xattr_check_block(inode, bh); |
|
if (error) { |
|
brelse(bh); |
|
return ERR_PTR(error); |
|
} |
|
return bh; |
|
} |
|
|
|
/* |
|
* ext4_xattr_set_handle() |
|
* |
|
* Create, replace or remove an extended attribute for this inode. Value |
|
* is NULL to remove an existing extended attribute, and non-NULL to |
|
* either replace an existing extended attribute, or create a new extended |
|
* attribute. The flags XATTR_REPLACE and XATTR_CREATE |
|
* specify that an extended attribute must exist and must not exist |
|
* previous to the call, respectively. |
|
* |
|
* Returns 0, or a negative error number on failure. |
|
*/ |
|
int |
|
ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, |
|
const char *name, const void *value, size_t value_len, |
|
int flags) |
|
{ |
|
struct ext4_xattr_info i = { |
|
.name_index = name_index, |
|
.name = name, |
|
.value = value, |
|
.value_len = value_len, |
|
.in_inode = 0, |
|
}; |
|
struct ext4_xattr_ibody_find is = { |
|
.s = { .not_found = -ENODATA, }, |
|
}; |
|
struct ext4_xattr_block_find bs = { |
|
.s = { .not_found = -ENODATA, }, |
|
}; |
|
int no_expand; |
|
int error; |
|
|
|
if (!name) |
|
return -EINVAL; |
|
if (strlen(name) > 255) |
|
return -ERANGE; |
|
|
|
ext4_write_lock_xattr(inode, &no_expand); |
|
|
|
/* Check journal credits under write lock. */ |
|
if (ext4_handle_valid(handle)) { |
|
struct buffer_head *bh; |
|
int credits; |
|
|
|
bh = ext4_xattr_get_block(inode); |
|
if (IS_ERR(bh)) { |
|
error = PTR_ERR(bh); |
|
goto cleanup; |
|
} |
|
|
|
credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh, |
|
value_len, |
|
flags & XATTR_CREATE); |
|
brelse(bh); |
|
|
|
if (jbd2_handle_buffer_credits(handle) < credits) { |
|
error = -ENOSPC; |
|
goto cleanup; |
|
} |
|
WARN_ON_ONCE(!(current->flags & PF_MEMALLOC_NOFS)); |
|
} |
|
|
|
error = ext4_reserve_inode_write(handle, inode, &is.iloc); |
|
if (error) |
|
goto cleanup; |
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { |
|
struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); |
|
memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); |
|
ext4_clear_inode_state(inode, EXT4_STATE_NEW); |
|
} |
|
|
|
error = ext4_xattr_ibody_find(inode, &i, &is); |
|
if (error) |
|
goto cleanup; |
|
if (is.s.not_found) |
|
error = ext4_xattr_block_find(inode, &i, &bs); |
|
if (error) |
|
goto cleanup; |
|
if (is.s.not_found && bs.s.not_found) { |
|
error = -ENODATA; |
|
if (flags & XATTR_REPLACE) |
|
goto cleanup; |
|
error = 0; |
|
if (!value) |
|
goto cleanup; |
|
} else { |
|
error = -EEXIST; |
|
if (flags & XATTR_CREATE) |
|
goto cleanup; |
|
} |
|
|
|
if (!value) { |
|
if (!is.s.not_found) |
|
error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
|
else if (!bs.s.not_found) |
|
error = ext4_xattr_block_set(handle, inode, &i, &bs); |
|
} else { |
|
error = 0; |
|
/* Xattr value did not change? Save us some work and bail out */ |
|
if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) |
|
goto cleanup; |
|
if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) |
|
goto cleanup; |
|
|
|
if (ext4_has_feature_ea_inode(inode->i_sb) && |
|
(EXT4_XATTR_SIZE(i.value_len) > |
|
EXT4_XATTR_MIN_LARGE_EA_SIZE(inode->i_sb->s_blocksize))) |
|
i.in_inode = 1; |
|
retry_inode: |
|
error = ext4_xattr_ibody_set(handle, inode, &i, &is); |
|
if (!error && !bs.s.not_found) { |
|
i.value = NULL; |
|
error = ext4_xattr_block_set(handle, inode, &i, &bs); |
|
} else if (error == -ENOSPC) { |
|
if (EXT4_I(inode)->i_file_acl && !bs.s.base) { |
|
brelse(bs.bh); |
|
bs.bh = NULL; |
|
error = ext4_xattr_block_find(inode, &i, &bs); |
|
if (error) |
|
goto cleanup; |
|
} |
|
error = ext4_xattr_block_set(handle, inode, &i, &bs); |
|
if (!error && !is.s.not_found) { |
|
i.value = NULL; |
|
error = ext4_xattr_ibody_set(handle, inode, &i, |
|
&is); |
|
} else if (error == -ENOSPC) { |
|
/* |
|
* Xattr does not fit in the block, store at |
|
* external inode if possible. |
|
*/ |
|
if (ext4_has_feature_ea_inode(inode->i_sb) && |
|
i.value_len && !i.in_inode) { |
|
i.in_inode = 1; |
|
goto retry_inode; |
|
} |
|
} |
|
} |
|
} |
|
if (!error) { |
|
ext4_xattr_update_super_block(handle, inode->i_sb); |
|
inode->i_ctime = current_time(inode); |
|
if (!value) |
|
no_expand = 0; |
|
error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); |
|
/* |
|
* The bh is consumed by ext4_mark_iloc_dirty, even with |
|
* error != 0. |
|
*/ |
|
is.iloc.bh = NULL; |
|
if (IS_SYNC(inode)) |
|
ext4_handle_sync(handle); |
|
} |
|
ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR); |
|
|
|
cleanup: |
|
brelse(is.iloc.bh); |
|
brelse(bs.bh); |
|
ext4_write_unlock_xattr(inode, &no_expand); |
|
return error; |
|
} |
|
|
|
int ext4_xattr_set_credits(struct inode *inode, size_t value_len, |
|
bool is_create, int *credits) |
|
{ |
|
struct buffer_head *bh; |
|
int err; |
|
|
|
*credits = 0; |
|
|
|
if (!EXT4_SB(inode->i_sb)->s_journal) |
|
return 0; |
|
|
|
down_read(&EXT4_I(inode)->xattr_sem); |
|
|
|
bh = ext4_xattr_get_block(inode); |
|
if (IS_ERR(bh)) { |
|
err = PTR_ERR(bh); |
|
} else { |
|
*credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh, |
|
value_len, is_create); |
|
brelse(bh); |
|
err = 0; |
|
} |
|
|
|
up_read(&EXT4_I(inode)->xattr_sem); |
|
return err; |
|
} |
|
|
|
/* |
|
* ext4_xattr_set() |
|
* |
|
* Like ext4_xattr_set_handle, but start from an inode. This extended |
|
* attribute modification is a filesystem transaction by itself. |
|
* |
|
* Returns 0, or a negative error number on failure. |
|
*/ |
|
int |
|
ext4_xattr_set(struct inode *inode, int name_index, const char *name, |
|
const void *value, size_t value_len, int flags) |
|
{ |
|
handle_t *handle; |
|
struct super_block *sb = inode->i_sb; |
|
int error, retries = 0; |
|
int credits; |
|
|
|
error = dquot_initialize(inode); |
|
if (error) |
|
return error; |
|
|
|
retry: |
|
error = ext4_xattr_set_credits(inode, value_len, flags & XATTR_CREATE, |
|
&credits); |
|
if (error) |
|
return error; |
|
|
|
handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); |
|
if (IS_ERR(handle)) { |
|
error = PTR_ERR(handle); |
|
} else { |
|
int error2; |
|
|
|
error = ext4_xattr_set_handle(handle, inode, name_index, name, |
|
value, value_len, flags); |
|
error2 = ext4_journal_stop(handle); |
|
if (error == -ENOSPC && |
|
ext4_should_retry_alloc(sb, &retries)) |
|
goto retry; |
|
if (error == 0) |
|
error = error2; |
|
} |
|
ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR); |
|
|
|
return error; |
|
} |
|
|
|
/* |
|
* Shift the EA entries in the inode to create space for the increased |
|
* i_extra_isize. |
|
*/ |
|
static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, |
|
int value_offs_shift, void *to, |
|
void *from, size_t n) |
|
{ |
|
struct ext4_xattr_entry *last = entry; |
|
int new_offs; |
|
|
|
/* We always shift xattr headers further thus offsets get lower */ |
|
BUG_ON(value_offs_shift > 0); |
|
|
|
/* Adjust the value offsets of the entries */ |
|
for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
|
if (!last->e_value_inum && last->e_value_size) { |
|
new_offs = le16_to_cpu(last->e_value_offs) + |
|
value_offs_shift; |
|
last->e_value_offs = cpu_to_le16(new_offs); |
|
} |
|
} |
|
/* Shift the entries by n bytes */ |
|
memmove(to, from, n); |
|
} |
|
|
|
/* |
|
* Move xattr pointed to by 'entry' from inode into external xattr block |
|
*/ |
|
static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode, |
|
struct ext4_inode *raw_inode, |
|
struct ext4_xattr_entry *entry) |
|
{ |
|
struct ext4_xattr_ibody_find *is = NULL; |
|
struct ext4_xattr_block_find *bs = NULL; |
|
char *buffer = NULL, *b_entry_name = NULL; |
|
size_t value_size = le32_to_cpu(entry->e_value_size); |
|
struct ext4_xattr_info i = { |
|
.value = NULL, |
|
.value_len = 0, |
|
.name_index = entry->e_name_index, |
|
.in_inode = !!entry->e_value_inum, |
|
}; |
|
struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); |
|
int error; |
|
|
|
is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); |
|
bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); |
|
buffer = kmalloc(value_size, GFP_NOFS); |
|
b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); |
|
if (!is || !bs || !buffer || !b_entry_name) { |
|
error = -ENOMEM; |
|
goto out; |
|
} |
|
|
|
is->s.not_found = -ENODATA; |
|
bs->s.not_found = -ENODATA; |
|
is->iloc.bh = NULL; |
|
bs->bh = NULL; |
|
|
|
/* Save the entry name and the entry value */ |
|
if (entry->e_value_inum) { |
|
error = ext4_xattr_inode_get(inode, entry, buffer, value_size); |
|
if (error) |
|
goto out; |
|
} else { |
|
size_t value_offs = le16_to_cpu(entry->e_value_offs); |
|
memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size); |
|
} |
|
|
|
memcpy(b_entry_name, entry->e_name, entry->e_name_len); |
|
b_entry_name[entry->e_name_len] = '\0'; |
|
i.name = b_entry_name; |
|
|
|
error = ext4_get_inode_loc(inode, &is->iloc); |
|
if (error) |
|
goto out; |
|
|
|
error = ext4_xattr_ibody_find(inode, &i, is); |
|
if (error) |
|
goto out; |
|
|
|
/* Remove the chosen entry from the inode */ |
|
error = ext4_xattr_ibody_set(handle, inode, &i, is); |
|
if (error) |
|
goto out; |
|
|
|
i.value = buffer; |
|
i.value_len = value_size; |
|
error = ext4_xattr_block_find(inode, &i, bs); |
|
if (error) |
|
goto out; |
|
|
|
/* Add entry which was removed from the inode into the block */ |
|
error = ext4_xattr_block_set(handle, inode, &i, bs); |
|
if (error) |
|
goto out; |
|
error = 0; |
|
out: |
|
kfree(b_entry_name); |
|
kfree(buffer); |
|
if (is) |
|
brelse(is->iloc.bh); |
|
if (bs) |
|
brelse(bs->bh); |
|
kfree(is); |
|
kfree(bs); |
|
|
|
return error; |
|
} |
|
|
|
static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode, |
|
struct ext4_inode *raw_inode, |
|
int isize_diff, size_t ifree, |
|
size_t bfree, int *total_ino) |
|
{ |
|
struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); |
|
struct ext4_xattr_entry *small_entry; |
|
struct ext4_xattr_entry *entry; |
|
struct ext4_xattr_entry *last; |
|
unsigned int entry_size; /* EA entry size */ |
|
unsigned int total_size; /* EA entry size + value size */ |
|
unsigned int min_total_size; |
|
int error; |
|
|
|
while (isize_diff > ifree) { |
|
entry = NULL; |
|
small_entry = NULL; |
|
min_total_size = ~0U; |
|
last = IFIRST(header); |
|
/* Find the entry best suited to be pushed into EA block */ |
|
for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { |
|
/* never move system.data out of the inode */ |
|
if ((last->e_name_len == 4) && |
|
(last->e_name_index == EXT4_XATTR_INDEX_SYSTEM) && |
|
!memcmp(last->e_name, "data", 4)) |
|
continue; |
|
total_size = EXT4_XATTR_LEN(last->e_name_len); |
|
if (!last->e_value_inum) |
|
total_size += EXT4_XATTR_SIZE( |
|
le32_to_cpu(last->e_value_size)); |
|
if (total_size <= bfree && |
|
total_size < min_total_size) { |
|
if (total_size + ifree < isize_diff) { |
|
small_entry = last; |
|
} else { |
|
entry = last; |
|
min_total_size = total_size; |
|
} |
|
} |
|
} |
|
|
|
if (entry == NULL) { |
|
if (small_entry == NULL) |
|
return -ENOSPC; |
|
entry = small_entry; |
|
} |
|
|
|
entry_size = EXT4_XATTR_LEN(entry->e_name_len); |
|
total_size = entry_size; |
|
if (!entry->e_value_inum) |
|
total_size += EXT4_XATTR_SIZE( |
|
le32_to_cpu(entry->e_value_size)); |
|
error = ext4_xattr_move_to_block(handle, inode, raw_inode, |
|
entry); |
|
if (error) |
|
return error; |
|
|
|
*total_ino -= entry_size; |
|
ifree += total_size; |
|
bfree -= total_size; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Expand an inode by new_extra_isize bytes when EAs are present. |
|
* Returns 0 on success or negative error number on failure. |
|
*/ |
|
int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, |
|
struct ext4_inode *raw_inode, handle_t *handle) |
|
{ |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); |
|
static unsigned int mnt_count; |
|
size_t min_offs; |
|
size_t ifree, bfree; |
|
int total_ino; |
|
void *base, *end; |
|
int error = 0, tried_min_extra_isize = 0; |
|
int s_min_extra_isize = le16_to_cpu(sbi->s_es->s_min_extra_isize); |
|
int isize_diff; /* How much do we need to grow i_extra_isize */ |
|
|
|
retry: |
|
isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize; |
|
if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) |
|
return 0; |
|
|
|
header = IHDR(inode, raw_inode); |
|
|
|
/* |
|
* Check if enough free space is available in the inode to shift the |
|
* entries ahead by new_extra_isize. |
|
*/ |
|
|
|
base = IFIRST(header); |
|
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; |
|
min_offs = end - base; |
|
total_ino = sizeof(struct ext4_xattr_ibody_header) + sizeof(u32); |
|
|
|
error = xattr_check_inode(inode, header, end); |
|
if (error) |
|
goto cleanup; |
|
|
|
ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino); |
|
if (ifree >= isize_diff) |
|
goto shift; |
|
|
|
/* |
|
* Enough free space isn't available in the inode, check if |
|
* EA block can hold new_extra_isize bytes. |
|
*/ |
|
if (EXT4_I(inode)->i_file_acl) { |
|
struct buffer_head *bh; |
|
|
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) { |
|
error = PTR_ERR(bh); |
|
goto cleanup; |
|
} |
|
error = ext4_xattr_check_block(inode, bh); |
|
if (error) { |
|
brelse(bh); |
|
goto cleanup; |
|
} |
|
base = BHDR(bh); |
|
end = bh->b_data + bh->b_size; |
|
min_offs = end - base; |
|
bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base, |
|
NULL); |
|
brelse(bh); |
|
if (bfree + ifree < isize_diff) { |
|
if (!tried_min_extra_isize && s_min_extra_isize) { |
|
tried_min_extra_isize++; |
|
new_extra_isize = s_min_extra_isize; |
|
goto retry; |
|
} |
|
error = -ENOSPC; |
|
goto cleanup; |
|
} |
|
} else { |
|
bfree = inode->i_sb->s_blocksize; |
|
} |
|
|
|
error = ext4_xattr_make_inode_space(handle, inode, raw_inode, |
|
isize_diff, ifree, bfree, |
|
&total_ino); |
|
if (error) { |
|
if (error == -ENOSPC && !tried_min_extra_isize && |
|
s_min_extra_isize) { |
|
tried_min_extra_isize++; |
|
new_extra_isize = s_min_extra_isize; |
|
goto retry; |
|
} |
|
goto cleanup; |
|
} |
|
shift: |
|
/* Adjust the offsets and shift the remaining entries ahead */ |
|
ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize |
|
- new_extra_isize, (void *)raw_inode + |
|
EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, |
|
(void *)header, total_ino); |
|
EXT4_I(inode)->i_extra_isize = new_extra_isize; |
|
|
|
cleanup: |
|
if (error && (mnt_count != le16_to_cpu(sbi->s_es->s_mnt_count))) { |
|
ext4_warning(inode->i_sb, "Unable to expand inode %lu. Delete some EAs or run e2fsck.", |
|
inode->i_ino); |
|
mnt_count = le16_to_cpu(sbi->s_es->s_mnt_count); |
|
} |
|
return error; |
|
} |
|
|
|
#define EIA_INCR 16 /* must be 2^n */ |
|
#define EIA_MASK (EIA_INCR - 1) |
|
|
|
/* Add the large xattr @inode into @ea_inode_array for deferred iput(). |
|
* If @ea_inode_array is new or full it will be grown and the old |
|
* contents copied over. |
|
*/ |
|
static int |
|
ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, |
|
struct inode *inode) |
|
{ |
|
if (*ea_inode_array == NULL) { |
|
/* |
|
* Start with 15 inodes, so it fits into a power-of-two size. |
|
* If *ea_inode_array is NULL, this is essentially offsetof() |
|
*/ |
|
(*ea_inode_array) = |
|
kmalloc(offsetof(struct ext4_xattr_inode_array, |
|
inodes[EIA_MASK]), |
|
GFP_NOFS); |
|
if (*ea_inode_array == NULL) |
|
return -ENOMEM; |
|
(*ea_inode_array)->count = 0; |
|
} else if (((*ea_inode_array)->count & EIA_MASK) == EIA_MASK) { |
|
/* expand the array once all 15 + n * 16 slots are full */ |
|
struct ext4_xattr_inode_array *new_array = NULL; |
|
int count = (*ea_inode_array)->count; |
|
|
|
/* if new_array is NULL, this is essentially offsetof() */ |
|
new_array = kmalloc( |
|
offsetof(struct ext4_xattr_inode_array, |
|
inodes[count + EIA_INCR]), |
|
GFP_NOFS); |
|
if (new_array == NULL) |
|
return -ENOMEM; |
|
memcpy(new_array, *ea_inode_array, |
|
offsetof(struct ext4_xattr_inode_array, inodes[count])); |
|
kfree(*ea_inode_array); |
|
*ea_inode_array = new_array; |
|
} |
|
(*ea_inode_array)->inodes[(*ea_inode_array)->count++] = inode; |
|
return 0; |
|
} |
|
|
|
/* |
|
* ext4_xattr_delete_inode() |
|
* |
|
* Free extended attribute resources associated with this inode. Traverse |
|
* all entries and decrement reference on any xattr inodes associated with this |
|
* inode. This is called immediately before an inode is freed. We have exclusive |
|
* access to the inode. If an orphan inode is deleted it will also release its |
|
* references on xattr block and xattr inodes. |
|
*/ |
|
int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, |
|
struct ext4_xattr_inode_array **ea_inode_array, |
|
int extra_credits) |
|
{ |
|
struct buffer_head *bh = NULL; |
|
struct ext4_xattr_ibody_header *header; |
|
struct ext4_iloc iloc = { .bh = NULL }; |
|
struct ext4_xattr_entry *entry; |
|
struct inode *ea_inode; |
|
int error; |
|
|
|
error = ext4_journal_ensure_credits(handle, extra_credits, |
|
ext4_free_metadata_revoke_credits(inode->i_sb, 1)); |
|
if (error < 0) { |
|
EXT4_ERROR_INODE(inode, "ensure credits (error %d)", error); |
|
goto cleanup; |
|
} |
|
|
|
if (ext4_has_feature_ea_inode(inode->i_sb) && |
|
ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { |
|
|
|
error = ext4_get_inode_loc(inode, &iloc); |
|
if (error) { |
|
EXT4_ERROR_INODE(inode, "inode loc (error %d)", error); |
|
goto cleanup; |
|
} |
|
|
|
error = ext4_journal_get_write_access(handle, iloc.bh); |
|
if (error) { |
|
EXT4_ERROR_INODE(inode, "write access (error %d)", |
|
error); |
|
goto cleanup; |
|
} |
|
|
|
header = IHDR(inode, ext4_raw_inode(&iloc)); |
|
if (header->h_magic == cpu_to_le32(EXT4_XATTR_MAGIC)) |
|
ext4_xattr_inode_dec_ref_all(handle, inode, iloc.bh, |
|
IFIRST(header), |
|
false /* block_csum */, |
|
ea_inode_array, |
|
extra_credits, |
|
false /* skip_quota */); |
|
} |
|
|
|
if (EXT4_I(inode)->i_file_acl) { |
|
bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); |
|
if (IS_ERR(bh)) { |
|
error = PTR_ERR(bh); |
|
if (error == -EIO) { |
|
EXT4_ERROR_INODE_ERR(inode, EIO, |
|
"block %llu read error", |
|
EXT4_I(inode)->i_file_acl); |
|
} |
|
bh = NULL; |
|
goto cleanup; |
|
} |
|
error = ext4_xattr_check_block(inode, bh); |
|
if (error) |
|
goto cleanup; |
|
|
|
if (ext4_has_feature_ea_inode(inode->i_sb)) { |
|
for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry); |
|
entry = EXT4_XATTR_NEXT(entry)) { |
|
if (!entry->e_value_inum) |
|
continue; |
|
error = ext4_xattr_inode_iget(inode, |
|
le32_to_cpu(entry->e_value_inum), |
|
le32_to_cpu(entry->e_hash), |
|
&ea_inode); |
|
if (error) |
|
continue; |
|
ext4_xattr_inode_free_quota(inode, ea_inode, |
|
le32_to_cpu(entry->e_value_size)); |
|
iput(ea_inode); |
|
} |
|
|
|
} |
|
|
|
ext4_xattr_release_block(handle, inode, bh, ea_inode_array, |
|
extra_credits); |
|
/* |
|
* Update i_file_acl value in the same transaction that releases |
|
* block. |
|
*/ |
|
EXT4_I(inode)->i_file_acl = 0; |
|
error = ext4_mark_inode_dirty(handle, inode); |
|
if (error) { |
|
EXT4_ERROR_INODE(inode, "mark inode dirty (error %d)", |
|
error); |
|
goto cleanup; |
|
} |
|
ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR); |
|
} |
|
error = 0; |
|
cleanup: |
|
brelse(iloc.bh); |
|
brelse(bh); |
|
return error; |
|
} |
|
|
|
void ext4_xattr_inode_array_free(struct ext4_xattr_inode_array *ea_inode_array) |
|
{ |
|
int idx; |
|
|
|
if (ea_inode_array == NULL) |
|
return; |
|
|
|
for (idx = 0; idx < ea_inode_array->count; ++idx) |
|
iput(ea_inode_array->inodes[idx]); |
|
kfree(ea_inode_array); |
|
} |
|
|
|
/* |
|
* ext4_xattr_block_cache_insert() |
|
* |
|
* Create a new entry in the extended attribute block cache, and insert |
|
* it unless such an entry is already in the cache. |
|
* |
|
* Returns 0, or a negative error number on failure. |
|
*/ |
|
static void |
|
ext4_xattr_block_cache_insert(struct mb_cache *ea_block_cache, |
|
struct buffer_head *bh) |
|
{ |
|
struct ext4_xattr_header *header = BHDR(bh); |
|
__u32 hash = le32_to_cpu(header->h_hash); |
|
int reusable = le32_to_cpu(header->h_refcount) < |
|
EXT4_XATTR_REFCOUNT_MAX; |
|
int error; |
|
|
|
if (!ea_block_cache) |
|
return; |
|
error = mb_cache_entry_create(ea_block_cache, GFP_NOFS, hash, |
|
bh->b_blocknr, reusable); |
|
if (error) { |
|
if (error == -EBUSY) |
|
ea_bdebug(bh, "already in cache"); |
|
} else |
|
ea_bdebug(bh, "inserting [%x]", (int)hash); |
|
} |
|
|
|
/* |
|
* ext4_xattr_cmp() |
|
* |
|
* Compare two extended attribute blocks for equality. |
|
* |
|
* Returns 0 if the blocks are equal, 1 if they differ, and |
|
* a negative error number on errors. |
|
*/ |
|
static int |
|
ext4_xattr_cmp(struct ext4_xattr_header *header1, |
|
struct ext4_xattr_header *header2) |
|
{ |
|
struct ext4_xattr_entry *entry1, *entry2; |
|
|
|
entry1 = ENTRY(header1+1); |
|
entry2 = ENTRY(header2+1); |
|
while (!IS_LAST_ENTRY(entry1)) { |
|
if (IS_LAST_ENTRY(entry2)) |
|
return 1; |
|
if (entry1->e_hash != entry2->e_hash || |
|
entry1->e_name_index != entry2->e_name_index || |
|
entry1->e_name_len != entry2->e_name_len || |
|
entry1->e_value_size != entry2->e_value_size || |
|
entry1->e_value_inum != entry2->e_value_inum || |
|
memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) |
|
return 1; |
|
if (!entry1->e_value_inum && |
|
memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), |
|
(char *)header2 + le16_to_cpu(entry2->e_value_offs), |
|
le32_to_cpu(entry1->e_value_size))) |
|
return 1; |
|
|
|
entry1 = EXT4_XATTR_NEXT(entry1); |
|
entry2 = EXT4_XATTR_NEXT(entry2); |
|
} |
|
if (!IS_LAST_ENTRY(entry2)) |
|
return 1; |
|
return 0; |
|
} |
|
|
|
/* |
|
* ext4_xattr_block_cache_find() |
|
* |
|
* Find an identical extended attribute block. |
|
* |
|
* Returns a pointer to the block found, or NULL if such a block was |
|
* not found or an error occurred. |
|
*/ |
|
static struct buffer_head * |
|
ext4_xattr_block_cache_find(struct inode *inode, |
|
struct ext4_xattr_header *header, |
|
struct mb_cache_entry **pce) |
|
{ |
|
__u32 hash = le32_to_cpu(header->h_hash); |
|
struct mb_cache_entry *ce; |
|
struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); |
|
|
|
if (!ea_block_cache) |
|
return NULL; |
|
if (!header->h_hash) |
|
return NULL; /* never share */ |
|
ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); |
|
ce = mb_cache_entry_find_first(ea_block_cache, hash); |
|
while (ce) { |
|
struct buffer_head *bh; |
|
|
|
bh = ext4_sb_bread(inode->i_sb, ce->e_value, REQ_PRIO); |
|
if (IS_ERR(bh)) { |
|
if (PTR_ERR(bh) == -ENOMEM) |
|
return NULL; |
|
bh = NULL; |
|
EXT4_ERROR_INODE(inode, "block %lu read error", |
|
(unsigned long)ce->e_value); |
|
} else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { |
|
*pce = ce; |
|
return bh; |
|
} |
|
brelse(bh); |
|
ce = mb_cache_entry_find_next(ea_block_cache, ce); |
|
} |
|
return NULL; |
|
} |
|
|
|
#define NAME_HASH_SHIFT 5 |
|
#define VALUE_HASH_SHIFT 16 |
|
|
|
/* |
|
* ext4_xattr_hash_entry() |
|
* |
|
* Compute the hash of an extended attribute. |
|
*/ |
|
static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value, |
|
size_t value_count) |
|
{ |
|
__u32 hash = 0; |
|
|
|
while (name_len--) { |
|
hash = (hash << NAME_HASH_SHIFT) ^ |
|
(hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ |
|
*name++; |
|
} |
|
while (value_count--) { |
|
hash = (hash << VALUE_HASH_SHIFT) ^ |
|
(hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ |
|
le32_to_cpu(*value++); |
|
} |
|
return cpu_to_le32(hash); |
|
} |
|
|
|
#undef NAME_HASH_SHIFT |
|
#undef VALUE_HASH_SHIFT |
|
|
|
#define BLOCK_HASH_SHIFT 16 |
|
|
|
/* |
|
* ext4_xattr_rehash() |
|
* |
|
* Re-compute the extended attribute hash value after an entry has changed. |
|
*/ |
|
static void ext4_xattr_rehash(struct ext4_xattr_header *header) |
|
{ |
|
struct ext4_xattr_entry *here; |
|
__u32 hash = 0; |
|
|
|
here = ENTRY(header+1); |
|
while (!IS_LAST_ENTRY(here)) { |
|
if (!here->e_hash) { |
|
/* Block is not shared if an entry's hash value == 0 */ |
|
hash = 0; |
|
break; |
|
} |
|
hash = (hash << BLOCK_HASH_SHIFT) ^ |
|
(hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ |
|
le32_to_cpu(here->e_hash); |
|
here = EXT4_XATTR_NEXT(here); |
|
} |
|
header->h_hash = cpu_to_le32(hash); |
|
} |
|
|
|
#undef BLOCK_HASH_SHIFT |
|
|
|
#define HASH_BUCKET_BITS 10 |
|
|
|
struct mb_cache * |
|
ext4_xattr_create_cache(void) |
|
{ |
|
return mb_cache_create(HASH_BUCKET_BITS); |
|
} |
|
|
|
void ext4_xattr_destroy_cache(struct mb_cache *cache) |
|
{ |
|
if (cache) |
|
mb_cache_destroy(cache); |
|
} |
|
|
|
|