3178 строки
83 KiB
C
3178 строки
83 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* linux/fs/ext4/xattr.c
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*
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* Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
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*
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* Fix by Harrison Xing <harrison@mountainviewdata.com>.
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* Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>.
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* Extended attributes for symlinks and special files added per
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* suggestion of Luka Renko <luka.renko@hermes.si>.
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* xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
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* Red Hat Inc.
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* ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz
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* and Andreas Gruenbacher <agruen@suse.de>.
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*/
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/*
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* Extended attributes are stored directly in inodes (on file systems with
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* inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
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* field contains the block number if an inode uses an additional block. All
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* 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.
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* Identical blocks are detected by keeping a cache of blocks that have
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* recently been accessed.
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*
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* The attributes in inodes and on blocks have a different header; the entries
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* are stored in the same format:
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*
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* +------------------+
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* | header |
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* | entry 1 | |
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* | entry 2 | | growing downwards
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* | entry 3 | v
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* | four null bytes |
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* | . . . |
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* | value 1 | ^
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* | value 3 | | growing upwards
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* | value 2 | |
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* +------------------+
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*
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* The header is followed by multiple entry descriptors. In disk blocks, the
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* entry descriptors are kept sorted. In inodes, they are unsorted. The
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* attribute values are aligned to the end of the block in no specific order.
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*
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* Locking strategy
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* ----------------
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* EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem.
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* EA blocks are only changed if they are exclusive to an inode, so
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* holding xattr_sem also means that nothing but the EA block's reference
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* count can change. Multiple writers to the same block are synchronized
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* by the buffer lock.
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*/
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#include <linux/init.h>
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#include <linux/fs.h>
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#include <linux/slab.h>
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#include <linux/mbcache.h>
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#include <linux/quotaops.h>
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#include <linux/iversion.h>
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#include "ext4_jbd2.h"
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#include "ext4.h"
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#include "xattr.h"
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#include "acl.h"
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#ifdef EXT4_XATTR_DEBUG
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# define ea_idebug(inode, fmt, ...) \
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printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
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inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
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# define ea_bdebug(bh, fmt, ...) \
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printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
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bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
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#else
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# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
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# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
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#endif
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static void ext4_xattr_block_cache_insert(struct mb_cache *,
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struct buffer_head *);
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static struct buffer_head *
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ext4_xattr_block_cache_find(struct inode *, struct ext4_xattr_header *,
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struct mb_cache_entry **);
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static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value,
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size_t value_count);
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static __le32 ext4_xattr_hash_entry_signed(char *name, size_t name_len, __le32 *value,
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size_t value_count);
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static void ext4_xattr_rehash(struct ext4_xattr_header *);
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static const struct xattr_handler * const ext4_xattr_handler_map[] = {
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[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,
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#endif
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[EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler,
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#ifdef CONFIG_EXT4_FS_SECURITY
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[EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler,
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#endif
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[EXT4_XATTR_INDEX_HURD] = &ext4_xattr_hurd_handler,
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};
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const struct xattr_handler *ext4_xattr_handlers[] = {
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&ext4_xattr_user_handler,
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&ext4_xattr_trusted_handler,
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#ifdef CONFIG_EXT4_FS_POSIX_ACL
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&posix_acl_access_xattr_handler,
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&posix_acl_default_xattr_handler,
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#endif
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#ifdef CONFIG_EXT4_FS_SECURITY
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&ext4_xattr_security_handler,
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#endif
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&ext4_xattr_hurd_handler,
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NULL
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};
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#define EA_BLOCK_CACHE(inode) (((struct ext4_sb_info *) \
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inode->i_sb->s_fs_info)->s_ea_block_cache)
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#define EA_INODE_CACHE(inode) (((struct ext4_sb_info *) \
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inode->i_sb->s_fs_info)->s_ea_inode_cache)
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static int
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ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array,
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struct inode *inode);
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#ifdef CONFIG_LOCKDEP
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void ext4_xattr_inode_set_class(struct inode *ea_inode)
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{
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lockdep_set_subclass(&ea_inode->i_rwsem, 1);
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}
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#endif
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static __le32 ext4_xattr_block_csum(struct inode *inode,
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sector_t block_nr,
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struct ext4_xattr_header *hdr)
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{
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struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
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__u32 csum;
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__le64 dsk_block_nr = cpu_to_le64(block_nr);
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__u32 dummy_csum = 0;
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int offset = offsetof(struct ext4_xattr_header, h_checksum);
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csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr,
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sizeof(dsk_block_nr));
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csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset);
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csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
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offset += sizeof(dummy_csum);
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csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset,
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EXT4_BLOCK_SIZE(inode->i_sb) - offset);
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return cpu_to_le32(csum);
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}
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static int ext4_xattr_block_csum_verify(struct inode *inode,
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struct buffer_head *bh)
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{
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struct ext4_xattr_header *hdr = BHDR(bh);
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int ret = 1;
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if (ext4_has_metadata_csum(inode->i_sb)) {
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lock_buffer(bh);
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ret = (hdr->h_checksum == ext4_xattr_block_csum(inode,
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bh->b_blocknr, hdr));
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unlock_buffer(bh);
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}
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return ret;
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}
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static void ext4_xattr_block_csum_set(struct inode *inode,
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struct buffer_head *bh)
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{
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if (ext4_has_metadata_csum(inode->i_sb))
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BHDR(bh)->h_checksum = ext4_xattr_block_csum(inode,
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bh->b_blocknr, BHDR(bh));
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}
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static inline const struct xattr_handler *
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ext4_xattr_handler(int name_index)
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{
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const struct xattr_handler *handler = NULL;
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if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
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handler = ext4_xattr_handler_map[name_index];
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return handler;
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}
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static int
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ext4_xattr_check_entries(struct ext4_xattr_entry *entry, void *end,
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void *value_start)
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{
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struct ext4_xattr_entry *e = entry;
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/* Find the end of the names list */
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while (!IS_LAST_ENTRY(e)) {
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struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e);
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if ((void *)next >= end)
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return -EFSCORRUPTED;
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if (strnlen(e->e_name, e->e_name_len) != e->e_name_len)
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return -EFSCORRUPTED;
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e = next;
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}
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/* Check the values */
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while (!IS_LAST_ENTRY(entry)) {
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u32 size = le32_to_cpu(entry->e_value_size);
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if (size > EXT4_XATTR_SIZE_MAX)
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return -EFSCORRUPTED;
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if (size != 0 && entry->e_value_inum == 0) {
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u16 offs = le16_to_cpu(entry->e_value_offs);
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void *value;
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/*
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* The value cannot overlap the names, and the value
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* with padding cannot extend beyond 'end'. Check both
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* the padded and unpadded sizes, since the size may
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* overflow to 0 when adding padding.
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*/
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if (offs > end - value_start)
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return -EFSCORRUPTED;
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value = value_start + offs;
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if (value < (void *)e + sizeof(u32) ||
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size > end - value ||
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EXT4_XATTR_SIZE(size) > end - value)
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return -EFSCORRUPTED;
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}
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entry = EXT4_XATTR_NEXT(entry);
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}
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return 0;
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}
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static inline int
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__ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh,
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const char *function, unsigned int line)
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{
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int error = -EFSCORRUPTED;
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if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
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BHDR(bh)->h_blocks != cpu_to_le32(1))
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goto errout;
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if (buffer_verified(bh))
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return 0;
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error = -EFSBADCRC;
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if (!ext4_xattr_block_csum_verify(inode, bh))
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goto errout;
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error = ext4_xattr_check_entries(BFIRST(bh), bh->b_data + bh->b_size,
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bh->b_data);
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errout:
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if (error)
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__ext4_error_inode(inode, function, line, 0, -error,
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"corrupted xattr block %llu",
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(unsigned long long) bh->b_blocknr);
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else
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set_buffer_verified(bh);
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return error;
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}
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#define ext4_xattr_check_block(inode, bh) \
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__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)
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{
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int error = -EFSCORRUPTED;
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if (end - (void *)header < sizeof(*header) + sizeof(u32) ||
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(header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)))
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goto errout;
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error = ext4_xattr_check_entries(IFIRST(header), end, IFIRST(header));
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errout:
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if (error)
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__ext4_error_inode(inode, function, line, 0, -error,
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"corrupted in-inode xattr");
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return error;
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}
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#define xattr_check_inode(inode, header, end) \
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__xattr_check_inode((inode), (header), (end), __func__, __LINE__)
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static int
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xattr_find_entry(struct inode *inode, struct ext4_xattr_entry **pentry,
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void *end, int name_index, const char *name, int sorted)
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{
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struct ext4_xattr_entry *entry, *next;
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size_t name_len;
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int cmp = 1;
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if (name == NULL)
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return -EINVAL;
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name_len = strlen(name);
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for (entry = *pentry; !IS_LAST_ENTRY(entry); entry = next) {
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next = EXT4_XATTR_NEXT(entry);
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if ((void *) next >= end) {
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EXT4_ERROR_INODE(inode, "corrupted xattr entries");
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return -EFSCORRUPTED;
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}
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cmp = name_index - entry->e_name_index;
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if (!cmp)
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cmp = name_len - entry->e_name_len;
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if (!cmp)
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cmp = memcmp(name, entry->e_name, name_len);
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if (cmp <= 0 && (sorted || cmp == 0))
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break;
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}
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*pentry = entry;
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return cmp ? -ENODATA : 0;
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}
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static u32
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ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size)
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{
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return ext4_chksum(sbi, sbi->s_csum_seed, buffer, size);
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}
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static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode)
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{
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return ((u64)ea_inode->i_ctime.tv_sec << 32) |
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(u32) inode_peek_iversion_raw(ea_inode);
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}
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static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count)
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{
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ea_inode->i_ctime.tv_sec = (u32)(ref_count >> 32);
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inode_set_iversion_raw(ea_inode, ref_count & 0xffffffff);
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}
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static u32 ext4_xattr_inode_get_hash(struct inode *ea_inode)
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{
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return (u32)ea_inode->i_atime.tv_sec;
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}
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static void ext4_xattr_inode_set_hash(struct inode *ea_inode, u32 hash)
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{
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ea_inode->i_atime.tv_sec = hash;
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}
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/*
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* Read the EA value from an inode.
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*/
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static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size)
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{
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int blocksize = 1 << ea_inode->i_blkbits;
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int bh_count = (size + blocksize - 1) >> ea_inode->i_blkbits;
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int tail_size = (size % blocksize) ?: blocksize;
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struct buffer_head *bhs_inline[8];
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struct buffer_head **bhs = bhs_inline;
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int i, ret;
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if (bh_count > ARRAY_SIZE(bhs_inline)) {
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bhs = kmalloc_array(bh_count, sizeof(*bhs), GFP_NOFS);
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if (!bhs)
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return -ENOMEM;
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}
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ret = ext4_bread_batch(ea_inode, 0 /* block */, bh_count,
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true /* wait */, bhs);
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if (ret)
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goto free_bhs;
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for (i = 0; i < bh_count; i++) {
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/* There shouldn't be any holes in ea_inode. */
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if (!bhs[i]) {
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ret = -EFSCORRUPTED;
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goto put_bhs;
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}
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memcpy((char *)buf + blocksize * i, bhs[i]->b_data,
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i < bh_count - 1 ? blocksize : tail_size);
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}
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ret = 0;
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put_bhs:
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for (i = 0; i < bh_count; i++)
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brelse(bhs[i]);
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free_bhs:
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if (bhs != bhs_inline)
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kfree(bhs);
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return ret;
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}
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#define EXT4_XATTR_INODE_GET_PARENT(inode) ((__u32)(inode)->i_mtime.tv_sec)
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static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino,
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u32 ea_inode_hash, struct inode **ea_inode)
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{
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struct inode *inode;
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int err;
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inode = ext4_iget(parent->i_sb, ea_ino, EXT4_IGET_NORMAL);
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if (IS_ERR(inode)) {
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err = PTR_ERR(inode);
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ext4_error(parent->i_sb,
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"error while reading EA inode %lu err=%d", ea_ino,
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err);
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return err;
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}
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if (is_bad_inode(inode)) {
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ext4_error(parent->i_sb,
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"error while reading EA inode %lu is_bad_inode",
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ea_ino);
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err = -EIO;
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goto error;
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}
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if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) {
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ext4_error(parent->i_sb,
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"EA inode %lu does not have EXT4_EA_INODE_FL flag",
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ea_ino);
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err = -EINVAL;
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goto error;
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}
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ext4_xattr_inode_set_class(inode);
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/*
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* Check whether this is an old Lustre-style xattr inode. Lustre
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* implementation does not have hash validation, rather it has a
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* backpointer from ea_inode to the parent inode.
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*/
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if (ea_inode_hash != ext4_xattr_inode_get_hash(inode) &&
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EXT4_XATTR_INODE_GET_PARENT(inode) == parent->i_ino &&
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inode->i_generation == parent->i_generation) {
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ext4_set_inode_state(inode, EXT4_STATE_LUSTRE_EA_INODE);
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ext4_xattr_inode_set_ref(inode, 1);
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} else {
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inode_lock(inode);
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inode->i_flags |= S_NOQUOTA;
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inode_unlock(inode);
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}
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*ea_inode = inode;
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return 0;
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error:
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iput(inode);
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return err;
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}
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/* Remove entry from mbcache when EA inode is getting evicted */
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void ext4_evict_ea_inode(struct inode *inode)
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{
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struct mb_cache_entry *oe;
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if (!EA_INODE_CACHE(inode))
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return;
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/* Wait for entry to get unused so that we can remove it */
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while ((oe = mb_cache_entry_delete_or_get(EA_INODE_CACHE(inode),
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ext4_xattr_inode_get_hash(inode), inode->i_ino))) {
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mb_cache_entry_wait_unused(oe);
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mb_cache_entry_put(EA_INODE_CACHE(inode), oe);
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}
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}
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static int
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ext4_xattr_inode_verify_hashes(struct inode *ea_inode,
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struct ext4_xattr_entry *entry, void *buffer,
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size_t size)
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{
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u32 hash;
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/* Verify stored hash matches calculated hash. */
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hash = ext4_xattr_inode_hash(EXT4_SB(ea_inode->i_sb), buffer, size);
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if (hash != ext4_xattr_inode_get_hash(ea_inode))
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return -EFSCORRUPTED;
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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);
|
|
/* All good? */
|
|
if (e_hash == entry->e_hash)
|
|
return 0;
|
|
|
|
/*
|
|
* Not good. Maybe the entry hash was calculated
|
|
* using the buggy signed char version?
|
|
*/
|
|
e_hash = ext4_xattr_hash_entry_signed(entry->e_name, entry->e_name_len,
|
|
&tmp_data, 1);
|
|
/* Still no match - bad */
|
|
if (e_hash != entry->e_hash)
|
|
return -EFSCORRUPTED;
|
|
|
|
/* Let people know about old hash */
|
|
pr_warn_once("ext4: filesystem with signed xattr name hash");
|
|
}
|
|
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, sb, EXT4_SB(sb)->s_sbh,
|
|
EXT4_JTR_NONE) == 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 ext4_iloc iloc;
|
|
s64 ref_count;
|
|
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);
|
|
}
|
|
} 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);
|
|
}
|
|
}
|
|
|
|
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,
|
|
parent->i_sb, bh, EXT4_JTR_NONE);
|
|
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, inode->i_sb, bh,
|
|
EXT4_JTR_NONE);
|
|
if (error)
|
|
goto out;
|
|
|
|
retry_ref:
|
|
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) {
|
|
struct mb_cache_entry *oe;
|
|
|
|
oe = mb_cache_entry_delete_or_get(ea_block_cache, hash,
|
|
bh->b_blocknr);
|
|
if (oe) {
|
|
unlock_buffer(bh);
|
|
mb_cache_entry_wait_unused(oe);
|
|
mb_cache_entry_put(ea_block_cache, oe);
|
|
goto retry_ref;
|
|
}
|
|
}
|
|
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) {
|
|
set_bit(MBE_REUSABLE_B, &ce->e_flags);
|
|
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, ea_inode->i_sb, bh,
|
|
EXT4_JTR_NONE);
|
|
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) {
|
|
if (ext4_xattr_inode_dec_ref(handle, ea_inode))
|
|
ext4_warning_inode(ea_inode,
|
|
"cleanup dec ref error %d", 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) {
|
|
if (ext4_xattr_inode_dec_ref(handle, ea_inode))
|
|
ext4_warning_inode(ea_inode, "cleanup dec ref error %d", err);
|
|
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) {
|
|
int offset = (char *)s->here - bs->bh->b_data;
|
|
|
|
BUFFER_TRACE(bs->bh, "get_write_access");
|
|
error = ext4_journal_get_write_access(handle, sb, bs->bh,
|
|
EXT4_JTR_NONE);
|
|
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) {
|
|
struct mb_cache_entry *oe;
|
|
|
|
oe = mb_cache_entry_delete_or_get(ea_block_cache,
|
|
hash, bs->bh->b_blocknr);
|
|
if (oe) {
|
|
/*
|
|
* Xattr block is getting reused. Leave
|
|
* it alone.
|
|
*/
|
|
mb_cache_entry_put(ea_block_cache, oe);
|
|
goto clone_block;
|
|
}
|
|
}
|
|
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;
|
|
}
|
|
clone_block:
|
|
unlock_buffer(bs->bh);
|
|
ea_bdebug(bs->bh, "cloning");
|
|
s->base = kmemdup(BHDR(bs->bh), bs->bh->b_size, GFP_NOFS);
|
|
error = -ENOMEM;
|
|
if (s->base == NULL)
|
|
goto cleanup;
|
|
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, sb, new_bh,
|
|
EXT4_JTR_NONE);
|
|
if (error)
|
|
goto cleanup_dquot;
|
|
lock_buffer(new_bh);
|
|
/*
|
|
* We have to be careful about races with
|
|
* adding references to xattr block. Once we
|
|
* hold buffer lock xattr block's state is
|
|
* stable so we can check the additional
|
|
* reference fits.
|
|
*/
|
|
ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1;
|
|
if (ref > EXT4_XATTR_REFCOUNT_MAX) {
|
|
/*
|
|
* 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;
|
|
}
|
|
BHDR(new_bh)->h_refcount = cpu_to_le32(ref);
|
|
if (ref == EXT4_XATTR_REFCOUNT_MAX)
|
|
clear_bit(MBE_REUSABLE_B, &ce->e_flags);
|
|
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);
|
|
block = ext4_new_meta_blocks(handle, inode, goal, 0,
|
|
NULL, &error);
|
|
if (error)
|
|
goto cleanup;
|
|
|
|
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, sb,
|
|
new_bh, EXT4_JTR_NONE);
|
|
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_INODE_HAS_XATTR_SPACE(inode))
|
|
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_INODE_HAS_XATTR_SPACE(inode))
|
|
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);
|
|
inode_inc_iversion(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, handle);
|
|
|
|
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, NULL);
|
|
|
|
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 = kvmalloc(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);
|
|
kvfree(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, inode->i_sb,
|
|
iloc.bh, EXT4_JTR_NONE);
|
|
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, handle);
|
|
}
|
|
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)) ^
|
|
(unsigned char)*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);
|
|
}
|
|
|
|
/*
|
|
* ext4_xattr_hash_entry_signed()
|
|
*
|
|
* Compute the hash of an extended attribute incorrectly.
|
|
*/
|
|
static __le32 ext4_xattr_hash_entry_signed(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)) ^
|
|
(signed char)*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);
|
|
}
|
|
|