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Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 * linux/fs/ext4/xattr.c
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003 *
4 * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
5 *
6 * Fix by Harrison Xing <harrison@mountainviewdata.com>.
Mingming Cao617ba132006-10-11 01:20:53 -07007 * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07008 * Extended attributes for symlinks and special files added per
9 * suggestion of Luka Renko <luka.renko@hermes.si>.
10 * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
11 * Red Hat Inc.
12 * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz
13 * and Andreas Gruenbacher <agruen@suse.de>.
14 */
15
16/*
17 * Extended attributes are stored directly in inodes (on file systems with
18 * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
19 * field contains the block number if an inode uses an additional block. All
20 * attributes must fit in the inode and one additional block. Blocks that
21 * contain the identical set of attributes may be shared among several inodes.
22 * Identical blocks are detected by keeping a cache of blocks that have
23 * recently been accessed.
24 *
25 * The attributes in inodes and on blocks have a different header; the entries
26 * are stored in the same format:
27 *
28 * +------------------+
29 * | header |
30 * | entry 1 | |
31 * | entry 2 | | growing downwards
32 * | entry 3 | v
33 * | four null bytes |
34 * | . . . |
35 * | value 1 | ^
36 * | value 3 | | growing upwards
37 * | value 2 | |
38 * +------------------+
39 *
40 * The header is followed by multiple entry descriptors. In disk blocks, the
41 * entry descriptors are kept sorted. In inodes, they are unsorted. The
42 * attribute values are aligned to the end of the block in no specific order.
43 *
44 * Locking strategy
45 * ----------------
Mingming Cao617ba132006-10-11 01:20:53 -070046 * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem.
Dave Kleikampac27a0e2006-10-11 01:20:50 -070047 * EA blocks are only changed if they are exclusive to an inode, so
48 * holding xattr_sem also means that nothing but the EA block's reference
49 * count can change. Multiple writers to the same block are synchronized
50 * by the buffer lock.
51 */
52
53#include <linux/init.h>
54#include <linux/fs.h>
55#include <linux/slab.h>
Jan Kara7a2508e2016-02-22 22:35:22 -050056#include <linux/mbcache.h>
Dave Kleikampac27a0e2006-10-11 01:20:50 -070057#include <linux/quotaops.h>
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040058#include "ext4_jbd2.h"
59#include "ext4.h"
Dave Kleikampac27a0e2006-10-11 01:20:50 -070060#include "xattr.h"
61#include "acl.h"
62
Mingming Cao617ba132006-10-11 01:20:53 -070063#ifdef EXT4_XATTR_DEBUG
Joe Perchesd74f3d22016-10-15 09:57:31 -040064# define ea_idebug(inode, fmt, ...) \
65 printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \
66 inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__)
67# define ea_bdebug(bh, fmt, ...) \
68 printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \
69 bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070070#else
Joe Perchesace36ad2012-03-19 23:11:43 -040071# define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
72# define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070073#endif
74
Jan Kara7a2508e2016-02-22 22:35:22 -050075static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *);
Mingming Cao617ba132006-10-11 01:20:53 -070076static struct buffer_head *ext4_xattr_cache_find(struct inode *,
77 struct ext4_xattr_header *,
Jan Kara7a2508e2016-02-22 22:35:22 -050078 struct mb_cache_entry **);
Mingming Cao617ba132006-10-11 01:20:53 -070079static void ext4_xattr_rehash(struct ext4_xattr_header *,
80 struct ext4_xattr_entry *);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070081
Eric Biggersd6006182017-04-29 23:47:50 -040082static const struct xattr_handler * const ext4_xattr_handler_map[] = {
Mingming Cao617ba132006-10-11 01:20:53 -070083 [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler,
Theodore Ts'o03010a32008-10-10 20:02:48 -040084#ifdef CONFIG_EXT4_FS_POSIX_ACL
Christoph Hellwig64e178a2013-12-20 05:16:44 -080085 [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
86 [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
Dave Kleikampac27a0e2006-10-11 01:20:50 -070087#endif
Mingming Cao617ba132006-10-11 01:20:53 -070088 [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler,
Theodore Ts'o03010a32008-10-10 20:02:48 -040089#ifdef CONFIG_EXT4_FS_SECURITY
Mingming Cao617ba132006-10-11 01:20:53 -070090 [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler,
Dave Kleikampac27a0e2006-10-11 01:20:50 -070091#endif
92};
93
Stephen Hemminger11e27522010-05-13 17:53:18 -070094const struct xattr_handler *ext4_xattr_handlers[] = {
Mingming Cao617ba132006-10-11 01:20:53 -070095 &ext4_xattr_user_handler,
96 &ext4_xattr_trusted_handler,
Theodore Ts'o03010a32008-10-10 20:02:48 -040097#ifdef CONFIG_EXT4_FS_POSIX_ACL
Christoph Hellwig64e178a2013-12-20 05:16:44 -080098 &posix_acl_access_xattr_handler,
99 &posix_acl_default_xattr_handler,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700100#endif
Theodore Ts'o03010a32008-10-10 20:02:48 -0400101#ifdef CONFIG_EXT4_FS_SECURITY
Mingming Cao617ba132006-10-11 01:20:53 -0700102 &ext4_xattr_security_handler,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700103#endif
104 NULL
105};
106
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400107#define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \
108 inode->i_sb->s_fs_info)->s_mb_cache)
109
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400110static __le32 ext4_xattr_block_csum(struct inode *inode,
111 sector_t block_nr,
112 struct ext4_xattr_header *hdr)
113{
114 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
Theodore Ts'od6a77102013-04-09 23:59:55 -0400115 __u32 csum;
Theodore Ts'od6a77102013-04-09 23:59:55 -0400116 __le64 dsk_block_nr = cpu_to_le64(block_nr);
Daeho Jeongb47820e2016-07-03 17:51:39 -0400117 __u32 dummy_csum = 0;
118 int offset = offsetof(struct ext4_xattr_header, h_checksum);
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400119
Theodore Ts'od6a77102013-04-09 23:59:55 -0400120 csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr,
121 sizeof(dsk_block_nr));
Daeho Jeongb47820e2016-07-03 17:51:39 -0400122 csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset);
123 csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum));
124 offset += sizeof(dummy_csum);
125 csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset,
126 EXT4_BLOCK_SIZE(inode->i_sb) - offset);
Tao Ma41eb70d2012-07-09 16:29:27 -0400127
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400128 return cpu_to_le32(csum);
129}
130
131static int ext4_xattr_block_csum_verify(struct inode *inode,
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400132 struct buffer_head *bh)
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400133{
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400134 struct ext4_xattr_header *hdr = BHDR(bh);
135 int ret = 1;
136
137 if (ext4_has_metadata_csum(inode->i_sb)) {
138 lock_buffer(bh);
139 ret = (hdr->h_checksum == ext4_xattr_block_csum(inode,
140 bh->b_blocknr, hdr));
141 unlock_buffer(bh);
142 }
143 return ret;
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400144}
145
146static void ext4_xattr_block_csum_set(struct inode *inode,
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400147 struct buffer_head *bh)
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400148{
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400149 if (ext4_has_metadata_csum(inode->i_sb))
150 BHDR(bh)->h_checksum = ext4_xattr_block_csum(inode,
151 bh->b_blocknr, BHDR(bh));
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400152}
153
Stephen Hemminger11e27522010-05-13 17:53:18 -0700154static inline const struct xattr_handler *
Mingming Cao617ba132006-10-11 01:20:53 -0700155ext4_xattr_handler(int name_index)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700156{
Stephen Hemminger11e27522010-05-13 17:53:18 -0700157 const struct xattr_handler *handler = NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700158
Mingming Cao617ba132006-10-11 01:20:53 -0700159 if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
160 handler = ext4_xattr_handler_map[name_index];
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700161 return handler;
162}
163
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700164static int
Eric Biggers2c4f9922017-04-29 23:56:52 -0400165ext4_xattr_check_entries(struct ext4_xattr_entry *entry, void *end,
166 void *value_start)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700167{
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400168 struct ext4_xattr_entry *e = entry;
169
Eric Biggersd7614cc2016-12-01 14:57:29 -0500170 /* Find the end of the names list */
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400171 while (!IS_LAST_ENTRY(e)) {
172 struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700173 if ((void *)next >= end)
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400174 return -EFSCORRUPTED;
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400175 e = next;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700176 }
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400177
Eric Biggersd7614cc2016-12-01 14:57:29 -0500178 /* Check the values */
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400179 while (!IS_LAST_ENTRY(entry)) {
Jan Kara2de58f12016-08-29 15:39:11 -0400180 if (entry->e_value_block != 0)
181 return -EFSCORRUPTED;
Eric Biggersd7614cc2016-12-01 14:57:29 -0500182 if (entry->e_value_size != 0) {
183 u16 offs = le16_to_cpu(entry->e_value_offs);
184 u32 size = le32_to_cpu(entry->e_value_size);
185 void *value;
186
187 /*
188 * The value cannot overlap the names, and the value
189 * with padding cannot extend beyond 'end'. Check both
190 * the padded and unpadded sizes, since the size may
191 * overflow to 0 when adding padding.
192 */
193 if (offs > end - value_start)
194 return -EFSCORRUPTED;
195 value = value_start + offs;
196 if (value < (void *)e + sizeof(u32) ||
197 size > end - value ||
198 EXT4_XATTR_SIZE(size) > end - value)
199 return -EFSCORRUPTED;
200 }
Darrick J. Wonga0626e752014-09-16 14:34:59 -0400201 entry = EXT4_XATTR_NEXT(entry);
202 }
203
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700204 return 0;
205}
206
207static inline int
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400208ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700209{
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400210 int error;
211
212 if (buffer_verified(bh))
213 return 0;
214
Mingming Cao617ba132006-10-11 01:20:53 -0700215 if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700216 BHDR(bh)->h_blocks != cpu_to_le32(1))
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400217 return -EFSCORRUPTED;
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400218 if (!ext4_xattr_block_csum_verify(inode, bh))
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400219 return -EFSBADCRC;
Eric Biggers2c4f9922017-04-29 23:56:52 -0400220 error = ext4_xattr_check_entries(BFIRST(bh), bh->b_data + bh->b_size,
221 bh->b_data);
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400222 if (!error)
223 set_buffer_verified(bh);
224 return error;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700225}
226
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400227static int
228__xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header,
229 void *end, const char *function, unsigned int line)
230{
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400231 int error = -EFSCORRUPTED;
232
Eric Biggers290ab232016-12-01 14:51:58 -0500233 if (end - (void *)header < sizeof(*header) + sizeof(u32) ||
Eric Biggers19962502016-10-15 09:39:31 -0400234 (header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)))
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400235 goto errout;
Eric Biggers2c4f9922017-04-29 23:56:52 -0400236 error = ext4_xattr_check_entries(IFIRST(header), end, IFIRST(header));
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400237errout:
238 if (error)
239 __ext4_error_inode(inode, function, line, 0,
240 "corrupted in-inode xattr");
241 return error;
242}
243
244#define xattr_check_inode(inode, header, end) \
245 __xattr_check_inode((inode), (header), (end), __func__, __LINE__)
246
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700247static int
Mingming Cao617ba132006-10-11 01:20:53 -0700248ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index,
Eric Biggers6ba644b2017-04-30 00:01:02 -0400249 const char *name, int sorted)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700250{
Mingming Cao617ba132006-10-11 01:20:53 -0700251 struct ext4_xattr_entry *entry;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700252 size_t name_len;
253 int cmp = 1;
254
255 if (name == NULL)
256 return -EINVAL;
257 name_len = strlen(name);
258 entry = *pentry;
Mingming Cao617ba132006-10-11 01:20:53 -0700259 for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700260 cmp = name_index - entry->e_name_index;
261 if (!cmp)
262 cmp = name_len - entry->e_name_len;
263 if (!cmp)
264 cmp = memcmp(name, entry->e_name, name_len);
265 if (cmp <= 0 && (sorted || cmp == 0))
266 break;
267 }
268 *pentry = entry;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700269 return cmp ? -ENODATA : 0;
270}
271
272static int
Mingming Cao617ba132006-10-11 01:20:53 -0700273ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700274 void *buffer, size_t buffer_size)
275{
276 struct buffer_head *bh = NULL;
Mingming Cao617ba132006-10-11 01:20:53 -0700277 struct ext4_xattr_entry *entry;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700278 size_t size;
279 int error;
Jan Kara7a2508e2016-02-22 22:35:22 -0500280 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700281
282 ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
283 name_index, name, buffer, (long)buffer_size);
284
285 error = -ENODATA;
Mingming Cao617ba132006-10-11 01:20:53 -0700286 if (!EXT4_I(inode)->i_file_acl)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700287 goto cleanup;
Joe Perchesace36ad2012-03-19 23:11:43 -0400288 ea_idebug(inode, "reading block %llu",
289 (unsigned long long)EXT4_I(inode)->i_file_acl);
Mingming Cao617ba132006-10-11 01:20:53 -0700290 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700291 if (!bh)
292 goto cleanup;
293 ea_bdebug(bh, "b_count=%d, refcount=%d",
294 atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400295 if (ext4_xattr_check_block(inode, bh)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400296 EXT4_ERROR_INODE(inode, "bad block %llu",
297 EXT4_I(inode)->i_file_acl);
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400298 error = -EFSCORRUPTED;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700299 goto cleanup;
300 }
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400301 ext4_xattr_cache_insert(ext4_mb_cache, bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700302 entry = BFIRST(bh);
Eric Biggers6ba644b2017-04-30 00:01:02 -0400303 error = ext4_xattr_find_entry(&entry, name_index, name, 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700304 if (error)
305 goto cleanup;
306 size = le32_to_cpu(entry->e_value_size);
307 if (buffer) {
308 error = -ERANGE;
309 if (size > buffer_size)
310 goto cleanup;
311 memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
312 size);
313 }
314 error = size;
315
316cleanup:
317 brelse(bh);
318 return error;
319}
320
Tao Ma879b3822012-12-05 10:28:46 -0500321int
Mingming Cao617ba132006-10-11 01:20:53 -0700322ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700323 void *buffer, size_t buffer_size)
324{
Mingming Cao617ba132006-10-11 01:20:53 -0700325 struct ext4_xattr_ibody_header *header;
326 struct ext4_xattr_entry *entry;
327 struct ext4_inode *raw_inode;
328 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700329 size_t size;
330 void *end;
331 int error;
332
Theodore Ts'o19f5fb72010-01-24 14:34:07 -0500333 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700334 return -ENODATA;
Mingming Cao617ba132006-10-11 01:20:53 -0700335 error = ext4_get_inode_loc(inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700336 if (error)
337 return error;
Mingming Cao617ba132006-10-11 01:20:53 -0700338 raw_inode = ext4_raw_inode(&iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700339 header = IHDR(inode, raw_inode);
Mingming Cao617ba132006-10-11 01:20:53 -0700340 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400341 error = xattr_check_inode(inode, header, end);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700342 if (error)
343 goto cleanup;
Eric Biggers6ba644b2017-04-30 00:01:02 -0400344 entry = IFIRST(header);
345 error = ext4_xattr_find_entry(&entry, name_index, name, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700346 if (error)
347 goto cleanup;
348 size = le32_to_cpu(entry->e_value_size);
349 if (buffer) {
350 error = -ERANGE;
351 if (size > buffer_size)
352 goto cleanup;
353 memcpy(buffer, (void *)IFIRST(header) +
354 le16_to_cpu(entry->e_value_offs), size);
355 }
356 error = size;
357
358cleanup:
359 brelse(iloc.bh);
360 return error;
361}
362
363/*
Mingming Cao617ba132006-10-11 01:20:53 -0700364 * ext4_xattr_get()
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700365 *
366 * Copy an extended attribute into the buffer
367 * provided, or compute the buffer size required.
368 * Buffer is NULL to compute the size of the buffer required.
369 *
370 * Returns a negative error number on failure, or the number of bytes
371 * used / required on success.
372 */
373int
Mingming Cao617ba132006-10-11 01:20:53 -0700374ext4_xattr_get(struct inode *inode, int name_index, const char *name,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700375 void *buffer, size_t buffer_size)
376{
377 int error;
378
Theodore Ts'o0db1ff22017-02-05 01:28:48 -0500379 if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
380 return -EIO;
381
Zhang Zhen230b8c1a2014-05-12 09:57:59 -0400382 if (strlen(name) > 255)
383 return -ERANGE;
384
Mingming Cao617ba132006-10-11 01:20:53 -0700385 down_read(&EXT4_I(inode)->xattr_sem);
386 error = ext4_xattr_ibody_get(inode, name_index, name, buffer,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700387 buffer_size);
388 if (error == -ENODATA)
Mingming Cao617ba132006-10-11 01:20:53 -0700389 error = ext4_xattr_block_get(inode, name_index, name, buffer,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700390 buffer_size);
Mingming Cao617ba132006-10-11 01:20:53 -0700391 up_read(&EXT4_I(inode)->xattr_sem);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700392 return error;
393}
394
395static int
Christoph Hellwig431547b2009-11-13 09:52:56 +0000396ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700397 char *buffer, size_t buffer_size)
398{
399 size_t rest = buffer_size;
400
Mingming Cao617ba132006-10-11 01:20:53 -0700401 for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
Stephen Hemminger11e27522010-05-13 17:53:18 -0700402 const struct xattr_handler *handler =
Mingming Cao617ba132006-10-11 01:20:53 -0700403 ext4_xattr_handler(entry->e_name_index);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700404
Andreas Gruenbacher764a5c62015-12-02 14:44:43 +0100405 if (handler && (!handler->list || handler->list(dentry))) {
406 const char *prefix = handler->prefix ?: handler->name;
407 size_t prefix_len = strlen(prefix);
408 size_t size = prefix_len + entry->e_name_len + 1;
409
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700410 if (buffer) {
411 if (size > rest)
412 return -ERANGE;
Andreas Gruenbacher764a5c62015-12-02 14:44:43 +0100413 memcpy(buffer, prefix, prefix_len);
414 buffer += prefix_len;
415 memcpy(buffer, entry->e_name, entry->e_name_len);
416 buffer += entry->e_name_len;
417 *buffer++ = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700418 }
419 rest -= size;
420 }
421 }
Andreas Gruenbacher764a5c62015-12-02 14:44:43 +0100422 return buffer_size - rest; /* total size */
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700423}
424
425static int
Christoph Hellwig431547b2009-11-13 09:52:56 +0000426ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700427{
David Howells2b0143b2015-03-17 22:25:59 +0000428 struct inode *inode = d_inode(dentry);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700429 struct buffer_head *bh = NULL;
430 int error;
Jan Kara7a2508e2016-02-22 22:35:22 -0500431 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700432
433 ea_idebug(inode, "buffer=%p, buffer_size=%ld",
434 buffer, (long)buffer_size);
435
436 error = 0;
Mingming Cao617ba132006-10-11 01:20:53 -0700437 if (!EXT4_I(inode)->i_file_acl)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700438 goto cleanup;
Joe Perchesace36ad2012-03-19 23:11:43 -0400439 ea_idebug(inode, "reading block %llu",
440 (unsigned long long)EXT4_I(inode)->i_file_acl);
Mingming Cao617ba132006-10-11 01:20:53 -0700441 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700442 error = -EIO;
443 if (!bh)
444 goto cleanup;
445 ea_bdebug(bh, "b_count=%d, refcount=%d",
446 atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400447 if (ext4_xattr_check_block(inode, bh)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400448 EXT4_ERROR_INODE(inode, "bad block %llu",
449 EXT4_I(inode)->i_file_acl);
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400450 error = -EFSCORRUPTED;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700451 goto cleanup;
452 }
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400453 ext4_xattr_cache_insert(ext4_mb_cache, bh);
Christoph Hellwig431547b2009-11-13 09:52:56 +0000454 error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700455
456cleanup:
457 brelse(bh);
458
459 return error;
460}
461
462static int
Christoph Hellwig431547b2009-11-13 09:52:56 +0000463ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700464{
David Howells2b0143b2015-03-17 22:25:59 +0000465 struct inode *inode = d_inode(dentry);
Mingming Cao617ba132006-10-11 01:20:53 -0700466 struct ext4_xattr_ibody_header *header;
467 struct ext4_inode *raw_inode;
468 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700469 void *end;
470 int error;
471
Theodore Ts'o19f5fb72010-01-24 14:34:07 -0500472 if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700473 return 0;
Mingming Cao617ba132006-10-11 01:20:53 -0700474 error = ext4_get_inode_loc(inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700475 if (error)
476 return error;
Mingming Cao617ba132006-10-11 01:20:53 -0700477 raw_inode = ext4_raw_inode(&iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700478 header = IHDR(inode, raw_inode);
Mingming Cao617ba132006-10-11 01:20:53 -0700479 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
Theodore Ts'o9e92f482016-03-22 16:13:15 -0400480 error = xattr_check_inode(inode, header, end);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700481 if (error)
482 goto cleanup;
Christoph Hellwig431547b2009-11-13 09:52:56 +0000483 error = ext4_xattr_list_entries(dentry, IFIRST(header),
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700484 buffer, buffer_size);
485
486cleanup:
487 brelse(iloc.bh);
488 return error;
489}
490
491/*
Eric Biggersba7ea1d2017-04-29 23:53:17 -0400492 * Inode operation listxattr()
493 *
494 * d_inode(dentry)->i_rwsem: don't care
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700495 *
496 * Copy a list of attribute names into the buffer
497 * provided, or compute the buffer size required.
498 * Buffer is NULL to compute the size of the buffer required.
499 *
500 * Returns a negative error number on failure, or the number of bytes
501 * used / required on success.
502 */
Eric Biggersba7ea1d2017-04-29 23:53:17 -0400503ssize_t
504ext4_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700505{
Theodore Ts'oeaeef862011-01-10 12:10:07 -0500506 int ret, ret2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700507
David Howells2b0143b2015-03-17 22:25:59 +0000508 down_read(&EXT4_I(d_inode(dentry))->xattr_sem);
Theodore Ts'oeaeef862011-01-10 12:10:07 -0500509 ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size);
510 if (ret < 0)
511 goto errout;
512 if (buffer) {
513 buffer += ret;
514 buffer_size -= ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700515 }
Theodore Ts'oeaeef862011-01-10 12:10:07 -0500516 ret = ext4_xattr_block_list(dentry, buffer, buffer_size);
517 if (ret < 0)
518 goto errout;
519 ret += ret2;
520errout:
David Howells2b0143b2015-03-17 22:25:59 +0000521 up_read(&EXT4_I(d_inode(dentry))->xattr_sem);
Theodore Ts'oeaeef862011-01-10 12:10:07 -0500522 return ret;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700523}
524
525/*
Mingming Cao617ba132006-10-11 01:20:53 -0700526 * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700527 * not set, set it.
528 */
Mingming Cao617ba132006-10-11 01:20:53 -0700529static void ext4_xattr_update_super_block(handle_t *handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700530 struct super_block *sb)
531{
Darrick J. Wonge2b911c2015-10-17 16:18:43 -0400532 if (ext4_has_feature_xattr(sb))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700533 return;
534
liang xie5d601252014-05-12 22:06:43 -0400535 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -0700536 if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) {
Darrick J. Wonge2b911c2015-10-17 16:18:43 -0400537 ext4_set_feature_xattr(sb);
Theodore Ts'oa0375152010-06-11 23:14:04 -0400538 ext4_handle_dirty_super(handle, sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700539 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700540}
541
542/*
Jan Karaec4cb1a2014-04-07 10:54:21 -0400543 * Release the xattr block BH: If the reference count is > 1, decrement it;
544 * otherwise free the block.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700545 */
546static void
Mingming Cao617ba132006-10-11 01:20:53 -0700547ext4_xattr_release_block(handle_t *handle, struct inode *inode,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700548 struct buffer_head *bh)
549{
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500550 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
551 u32 hash, ref;
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800552 int error = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700553
liang xie5d601252014-05-12 22:06:43 -0400554 BUFFER_TRACE(bh, "get_write_access");
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800555 error = ext4_journal_get_write_access(handle, bh);
556 if (error)
557 goto out;
558
559 lock_buffer(bh);
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500560 hash = le32_to_cpu(BHDR(bh)->h_hash);
561 ref = le32_to_cpu(BHDR(bh)->h_refcount);
562 if (ref == 1) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700563 ea_bdebug(bh, "refcount now=0; freeing");
Jan Kara82939d72016-02-22 11:50:13 -0500564 /*
565 * This must happen under buffer lock for
566 * ext4_xattr_block_set() to reliably detect freed block
567 */
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500568 mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700569 get_bh(bh);
Jan Karaec4cb1a2014-04-07 10:54:21 -0400570 unlock_buffer(bh);
Theodore Ts'oe6362602009-11-23 07:17:05 -0500571 ext4_free_blocks(handle, inode, bh, 0, 1,
572 EXT4_FREE_BLOCKS_METADATA |
573 EXT4_FREE_BLOCKS_FORGET);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700574 } else {
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500575 ref--;
576 BHDR(bh)->h_refcount = cpu_to_le32(ref);
577 if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) {
578 struct mb_cache_entry *ce;
579
580 ce = mb_cache_entry_get(ext4_mb_cache, hash,
581 bh->b_blocknr);
582 if (ce) {
583 ce->e_reusable = 1;
584 mb_cache_entry_put(ext4_mb_cache, ce);
585 }
586 }
587
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400588 ext4_xattr_block_csum_set(inode, bh);
Jan Karaec4cb1a2014-04-07 10:54:21 -0400589 /*
590 * Beware of this ugliness: Releasing of xattr block references
591 * from different inodes can race and so we have to protect
592 * from a race where someone else frees the block (and releases
593 * its journal_head) before we are done dirtying the buffer. In
594 * nojournal mode this race is harmless and we actually cannot
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400595 * call ext4_handle_dirty_metadata() with locked buffer as
Jan Karaec4cb1a2014-04-07 10:54:21 -0400596 * that function can call sync_dirty_buffer() so for that case
597 * we handle the dirtying after unlocking the buffer.
598 */
599 if (ext4_handle_valid(handle))
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400600 error = ext4_handle_dirty_metadata(handle, inode, bh);
Eric Sandeenc1bb05a2012-02-20 23:06:18 -0500601 unlock_buffer(bh);
Jan Karaec4cb1a2014-04-07 10:54:21 -0400602 if (!ext4_handle_valid(handle))
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400603 error = ext4_handle_dirty_metadata(handle, inode, bh);
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800604 if (IS_SYNC(inode))
Frank Mayhar03901312009-01-07 00:06:22 -0500605 ext4_handle_sync(handle);
Lukas Czerner1231b3a2013-02-18 12:12:07 -0500606 dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1));
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800607 ea_bdebug(bh, "refcount now=%d; releasing",
608 le32_to_cpu(BHDR(bh)->h_refcount));
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700609 }
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800610out:
611 ext4_std_error(inode->i_sb, error);
612 return;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700613}
614
Kalpak Shah6dd4ee72007-07-18 09:19:57 -0400615/*
616 * Find the available free space for EAs. This also returns the total number of
617 * bytes used by EA entries.
618 */
619static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last,
620 size_t *min_offs, void *base, int *total)
621{
622 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
Jan Kara1cba4232016-08-29 15:40:11 -0400623 if (last->e_value_size) {
Kalpak Shah6dd4ee72007-07-18 09:19:57 -0400624 size_t offs = le16_to_cpu(last->e_value_offs);
625 if (offs < *min_offs)
626 *min_offs = offs;
627 }
Theodore Ts'o7b1b2c12014-02-19 20:15:21 -0500628 if (total)
629 *total += EXT4_XATTR_LEN(last->e_name_len);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -0400630 }
631 return (*min_offs - ((void *)last - base) - sizeof(__u32));
632}
633
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700634static int
Mingming Cao617ba132006-10-11 01:20:53 -0700635ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700636{
Mingming Cao617ba132006-10-11 01:20:53 -0700637 struct ext4_xattr_entry *last;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700638 size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
639
640 /* Compute min_offs and last. */
641 last = s->first;
Mingming Cao617ba132006-10-11 01:20:53 -0700642 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
Jan Kara1cba4232016-08-29 15:40:11 -0400643 if (last->e_value_size) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700644 size_t offs = le16_to_cpu(last->e_value_offs);
645 if (offs < min_offs)
646 min_offs = offs;
647 }
648 }
649 free = min_offs - ((void *)last - s->base) - sizeof(__u32);
650 if (!s->not_found) {
Jan Kara1cba4232016-08-29 15:40:11 -0400651 if (s->here->e_value_size) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700652 size_t size = le32_to_cpu(s->here->e_value_size);
Mingming Cao617ba132006-10-11 01:20:53 -0700653 free += EXT4_XATTR_SIZE(size);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700654 }
Mingming Cao617ba132006-10-11 01:20:53 -0700655 free += EXT4_XATTR_LEN(name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700656 }
657 if (i->value) {
Wei Yuan5f80f622015-04-02 23:50:48 -0400658 if (free < EXT4_XATTR_LEN(name_len) +
Mingming Cao617ba132006-10-11 01:20:53 -0700659 EXT4_XATTR_SIZE(i->value_len))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700660 return -ENOSPC;
661 }
662
663 if (i->value && s->not_found) {
664 /* Insert the new name. */
Mingming Cao617ba132006-10-11 01:20:53 -0700665 size_t size = EXT4_XATTR_LEN(name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700666 size_t rest = (void *)last - (void *)s->here + sizeof(__u32);
667 memmove((void *)s->here + size, s->here, rest);
668 memset(s->here, 0, size);
669 s->here->e_name_index = i->name_index;
670 s->here->e_name_len = name_len;
671 memcpy(s->here->e_name, i->name, name_len);
672 } else {
Jan Kara1cba4232016-08-29 15:40:11 -0400673 if (s->here->e_value_size) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700674 void *first_val = s->base + min_offs;
675 size_t offs = le16_to_cpu(s->here->e_value_offs);
676 void *val = s->base + offs;
Mingming Cao617ba132006-10-11 01:20:53 -0700677 size_t size = EXT4_XATTR_SIZE(
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700678 le32_to_cpu(s->here->e_value_size));
679
Mingming Cao617ba132006-10-11 01:20:53 -0700680 if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700681 /* The old and the new value have the same
682 size. Just replace. */
683 s->here->e_value_size =
684 cpu_to_le32(i->value_len);
Theodore Ts'obd9926e2012-12-11 03:31:49 -0500685 if (i->value == EXT4_ZERO_XATTR_VALUE) {
686 memset(val, 0, size);
687 } else {
688 /* Clear pad bytes first. */
689 memset(val + size - EXT4_XATTR_PAD, 0,
690 EXT4_XATTR_PAD);
691 memcpy(val, i->value, i->value_len);
692 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700693 return 0;
694 }
695
696 /* Remove the old value. */
697 memmove(first_val + size, first_val, val - first_val);
698 memset(first_val, 0, size);
699 s->here->e_value_size = 0;
700 s->here->e_value_offs = 0;
701 min_offs += size;
702
703 /* Adjust all value offsets. */
704 last = s->first;
705 while (!IS_LAST_ENTRY(last)) {
706 size_t o = le16_to_cpu(last->e_value_offs);
Jan Kara1cba4232016-08-29 15:40:11 -0400707 if (last->e_value_size && o < offs)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700708 last->e_value_offs =
709 cpu_to_le16(o + size);
Mingming Cao617ba132006-10-11 01:20:53 -0700710 last = EXT4_XATTR_NEXT(last);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700711 }
712 }
713 if (!i->value) {
714 /* Remove the old name. */
Mingming Cao617ba132006-10-11 01:20:53 -0700715 size_t size = EXT4_XATTR_LEN(name_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700716 last = ENTRY((void *)last - size);
717 memmove(s->here, (void *)s->here + size,
718 (void *)last - (void *)s->here + sizeof(__u32));
719 memset(last, 0, size);
720 }
721 }
722
723 if (i->value) {
724 /* Insert the new value. */
725 s->here->e_value_size = cpu_to_le32(i->value_len);
726 if (i->value_len) {
Mingming Cao617ba132006-10-11 01:20:53 -0700727 size_t size = EXT4_XATTR_SIZE(i->value_len);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700728 void *val = s->base + min_offs - size;
729 s->here->e_value_offs = cpu_to_le16(min_offs - size);
Theodore Ts'obd9926e2012-12-11 03:31:49 -0500730 if (i->value == EXT4_ZERO_XATTR_VALUE) {
731 memset(val, 0, size);
732 } else {
733 /* Clear the pad bytes first. */
734 memset(val + size - EXT4_XATTR_PAD, 0,
735 EXT4_XATTR_PAD);
736 memcpy(val, i->value, i->value_len);
737 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700738 }
739 }
740 return 0;
741}
742
Mingming Cao617ba132006-10-11 01:20:53 -0700743struct ext4_xattr_block_find {
744 struct ext4_xattr_search s;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700745 struct buffer_head *bh;
746};
747
748static int
Mingming Cao617ba132006-10-11 01:20:53 -0700749ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i,
750 struct ext4_xattr_block_find *bs)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700751{
752 struct super_block *sb = inode->i_sb;
753 int error;
754
755 ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
756 i->name_index, i->name, i->value, (long)i->value_len);
757
Mingming Cao617ba132006-10-11 01:20:53 -0700758 if (EXT4_I(inode)->i_file_acl) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700759 /* The inode already has an extended attribute block. */
Mingming Cao617ba132006-10-11 01:20:53 -0700760 bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700761 error = -EIO;
762 if (!bs->bh)
763 goto cleanup;
764 ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
765 atomic_read(&(bs->bh->b_count)),
766 le32_to_cpu(BHDR(bs->bh)->h_refcount));
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -0400767 if (ext4_xattr_check_block(inode, bs->bh)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -0400768 EXT4_ERROR_INODE(inode, "bad block %llu",
769 EXT4_I(inode)->i_file_acl);
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400770 error = -EFSCORRUPTED;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700771 goto cleanup;
772 }
773 /* Find the named attribute. */
774 bs->s.base = BHDR(bs->bh);
775 bs->s.first = BFIRST(bs->bh);
776 bs->s.end = bs->bh->b_data + bs->bh->b_size;
777 bs->s.here = bs->s.first;
Mingming Cao617ba132006-10-11 01:20:53 -0700778 error = ext4_xattr_find_entry(&bs->s.here, i->name_index,
Eric Biggers6ba644b2017-04-30 00:01:02 -0400779 i->name, 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700780 if (error && error != -ENODATA)
781 goto cleanup;
782 bs->s.not_found = error;
783 }
784 error = 0;
785
786cleanup:
787 return error;
788}
789
790static int
Mingming Cao617ba132006-10-11 01:20:53 -0700791ext4_xattr_block_set(handle_t *handle, struct inode *inode,
792 struct ext4_xattr_info *i,
793 struct ext4_xattr_block_find *bs)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700794{
795 struct super_block *sb = inode->i_sb;
796 struct buffer_head *new_bh = NULL;
Mingming Cao617ba132006-10-11 01:20:53 -0700797 struct ext4_xattr_search *s = &bs->s;
Jan Kara7a2508e2016-02-22 22:35:22 -0500798 struct mb_cache_entry *ce = NULL;
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800799 int error = 0;
Jan Kara7a2508e2016-02-22 22:35:22 -0500800 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700801
Mingming Cao617ba132006-10-11 01:20:53 -0700802#define header(x) ((struct ext4_xattr_header *)(x))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700803
804 if (i->value && i->value_len > sb->s_blocksize)
805 return -ENOSPC;
806 if (s->base) {
liang xie5d601252014-05-12 22:06:43 -0400807 BUFFER_TRACE(bs->bh, "get_write_access");
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800808 error = ext4_journal_get_write_access(handle, bs->bh);
809 if (error)
810 goto cleanup;
811 lock_buffer(bs->bh);
812
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700813 if (header(s->base)->h_refcount == cpu_to_le32(1)) {
Jan Kara82939d72016-02-22 11:50:13 -0500814 __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash);
815
816 /*
817 * This must happen under buffer lock for
818 * ext4_xattr_block_set() to reliably detect modified
819 * block
820 */
Jan Kara7a2508e2016-02-22 22:35:22 -0500821 mb_cache_entry_delete_block(ext4_mb_cache, hash,
822 bs->bh->b_blocknr);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700823 ea_bdebug(bs->bh, "modifying in-place");
Mingming Cao617ba132006-10-11 01:20:53 -0700824 error = ext4_xattr_set_entry(i, s);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700825 if (!error) {
826 if (!IS_LAST_ENTRY(s->first))
Mingming Cao617ba132006-10-11 01:20:53 -0700827 ext4_xattr_rehash(header(s->base),
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700828 s->here);
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400829 ext4_xattr_cache_insert(ext4_mb_cache,
830 bs->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700831 }
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400832 ext4_xattr_block_csum_set(inode, bs->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700833 unlock_buffer(bs->bh);
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400834 if (error == -EFSCORRUPTED)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700835 goto bad_block;
836 if (!error)
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400837 error = ext4_handle_dirty_metadata(handle,
838 inode,
839 bs->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700840 if (error)
841 goto cleanup;
842 goto inserted;
843 } else {
844 int offset = (char *)s->here - bs->bh->b_data;
845
Mingming Cao8a2bfdc2007-02-28 20:13:35 -0800846 unlock_buffer(bs->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700847 ea_bdebug(bs->bh, "cloning");
Josef Bacik216553c2008-04-29 22:02:02 -0400848 s->base = kmalloc(bs->bh->b_size, GFP_NOFS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700849 error = -ENOMEM;
850 if (s->base == NULL)
851 goto cleanup;
852 memcpy(s->base, BHDR(bs->bh), bs->bh->b_size);
853 s->first = ENTRY(header(s->base)+1);
854 header(s->base)->h_refcount = cpu_to_le32(1);
855 s->here = ENTRY(s->base + offset);
856 s->end = s->base + bs->bh->b_size;
857 }
858 } else {
859 /* Allocate a buffer where we construct the new block. */
Josef Bacik216553c2008-04-29 22:02:02 -0400860 s->base = kzalloc(sb->s_blocksize, GFP_NOFS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700861 /* assert(header == s->base) */
862 error = -ENOMEM;
863 if (s->base == NULL)
864 goto cleanup;
Mingming Cao617ba132006-10-11 01:20:53 -0700865 header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700866 header(s->base)->h_blocks = cpu_to_le32(1);
867 header(s->base)->h_refcount = cpu_to_le32(1);
868 s->first = ENTRY(header(s->base)+1);
869 s->here = ENTRY(header(s->base)+1);
870 s->end = s->base + sb->s_blocksize;
871 }
872
Mingming Cao617ba132006-10-11 01:20:53 -0700873 error = ext4_xattr_set_entry(i, s);
Darrick J. Wong6a797d22015-10-17 16:16:04 -0400874 if (error == -EFSCORRUPTED)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700875 goto bad_block;
876 if (error)
877 goto cleanup;
878 if (!IS_LAST_ENTRY(s->first))
Mingming Cao617ba132006-10-11 01:20:53 -0700879 ext4_xattr_rehash(header(s->base), s->here);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700880
881inserted:
882 if (!IS_LAST_ENTRY(s->first)) {
Mingming Cao617ba132006-10-11 01:20:53 -0700883 new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700884 if (new_bh) {
885 /* We found an identical block in the cache. */
886 if (new_bh == bs->bh)
887 ea_bdebug(new_bh, "keeping");
888 else {
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500889 u32 ref;
890
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700891 /* The old block is released after updating
892 the inode. */
Lukas Czerner1231b3a2013-02-18 12:12:07 -0500893 error = dquot_alloc_block(inode,
894 EXT4_C2B(EXT4_SB(sb), 1));
Christoph Hellwig5dd40562010-03-03 09:05:00 -0500895 if (error)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700896 goto cleanup;
liang xie5d601252014-05-12 22:06:43 -0400897 BUFFER_TRACE(new_bh, "get_write_access");
Mingming Cao617ba132006-10-11 01:20:53 -0700898 error = ext4_journal_get_write_access(handle,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700899 new_bh);
900 if (error)
901 goto cleanup_dquot;
902 lock_buffer(new_bh);
Jan Kara82939d72016-02-22 11:50:13 -0500903 /*
904 * We have to be careful about races with
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500905 * freeing, rehashing or adding references to
906 * xattr block. Once we hold buffer lock xattr
907 * block's state is stable so we can check
908 * whether the block got freed / rehashed or
909 * not. Since we unhash mbcache entry under
910 * buffer lock when freeing / rehashing xattr
911 * block, checking whether entry is still
912 * hashed is reliable. Same rules hold for
913 * e_reusable handling.
Jan Kara82939d72016-02-22 11:50:13 -0500914 */
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500915 if (hlist_bl_unhashed(&ce->e_hash_list) ||
916 !ce->e_reusable) {
Jan Kara82939d72016-02-22 11:50:13 -0500917 /*
918 * Undo everything and check mbcache
919 * again.
920 */
921 unlock_buffer(new_bh);
922 dquot_free_block(inode,
923 EXT4_C2B(EXT4_SB(sb),
924 1));
925 brelse(new_bh);
Jan Kara7a2508e2016-02-22 22:35:22 -0500926 mb_cache_entry_put(ext4_mb_cache, ce);
Jan Kara82939d72016-02-22 11:50:13 -0500927 ce = NULL;
928 new_bh = NULL;
929 goto inserted;
930 }
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500931 ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1;
932 BHDR(new_bh)->h_refcount = cpu_to_le32(ref);
933 if (ref >= EXT4_XATTR_REFCOUNT_MAX)
934 ce->e_reusable = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700935 ea_bdebug(new_bh, "reusing; refcount now=%d",
Andreas Gruenbacher6048c642016-02-22 22:44:04 -0500936 ref);
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400937 ext4_xattr_block_csum_set(inode, new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700938 unlock_buffer(new_bh);
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400939 error = ext4_handle_dirty_metadata(handle,
940 inode,
941 new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700942 if (error)
943 goto cleanup_dquot;
944 }
Jan Kara7a2508e2016-02-22 22:35:22 -0500945 mb_cache_entry_touch(ext4_mb_cache, ce);
946 mb_cache_entry_put(ext4_mb_cache, ce);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700947 ce = NULL;
948 } else if (bs->bh && s->base == bs->bh->b_data) {
949 /* We were modifying this block in-place. */
950 ea_bdebug(bs->bh, "keeping this block");
951 new_bh = bs->bh;
952 get_bh(new_bh);
953 } else {
954 /* We need to allocate a new block */
Eric Sandeenfb0a3872009-09-16 14:45:10 -0400955 ext4_fsblk_t goal, block;
956
957 goal = ext4_group_first_block_no(sb,
Akinobu Mitad00a6d72008-04-17 10:38:59 -0400958 EXT4_I(inode)->i_block_group);
Eric Sandeenfb0a3872009-09-16 14:45:10 -0400959
960 /* non-extent files can't have physical blocks past 2^32 */
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400961 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
Eric Sandeenfb0a3872009-09-16 14:45:10 -0400962 goal = goal & EXT4_MAX_BLOCK_FILE_PHYS;
963
Allison Henderson55f020d2011-05-25 07:41:26 -0400964 block = ext4_new_meta_blocks(handle, inode, goal, 0,
965 NULL, &error);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700966 if (error)
967 goto cleanup;
Eric Sandeenfb0a3872009-09-16 14:45:10 -0400968
Dmitry Monakhov12e9b892010-05-16 22:00:00 -0400969 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
Eric Sandeenfb0a3872009-09-16 14:45:10 -0400970 BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS);
971
Joe Perchesace36ad2012-03-19 23:11:43 -0400972 ea_idebug(inode, "creating block %llu",
973 (unsigned long long)block);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700974
975 new_bh = sb_getblk(sb, block);
Wang Shilongaebf0242013-01-12 16:28:47 -0500976 if (unlikely(!new_bh)) {
Theodore Ts'o860d21e2013-01-12 16:19:36 -0500977 error = -ENOMEM;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700978getblk_failed:
Peter Huewe7dc57612011-02-21 21:01:42 -0500979 ext4_free_blocks(handle, inode, NULL, block, 1,
Theodore Ts'oe6362602009-11-23 07:17:05 -0500980 EXT4_FREE_BLOCKS_METADATA);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700981 goto cleanup;
982 }
983 lock_buffer(new_bh);
Mingming Cao617ba132006-10-11 01:20:53 -0700984 error = ext4_journal_get_create_access(handle, new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700985 if (error) {
986 unlock_buffer(new_bh);
Theodore Ts'o860d21e2013-01-12 16:19:36 -0500987 error = -EIO;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700988 goto getblk_failed;
989 }
990 memcpy(new_bh->b_data, s->base, new_bh->b_size);
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400991 ext4_xattr_block_csum_set(inode, new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700992 set_buffer_uptodate(new_bh);
993 unlock_buffer(new_bh);
T Makphaibulchoke9c191f72014-03-18 19:24:49 -0400994 ext4_xattr_cache_insert(ext4_mb_cache, new_bh);
Theodore Ts'odac7a4b2017-03-25 17:22:47 -0400995 error = ext4_handle_dirty_metadata(handle, inode,
996 new_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700997 if (error)
998 goto cleanup;
999 }
1000 }
1001
1002 /* Update the inode. */
Mingming Cao617ba132006-10-11 01:20:53 -07001003 EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001004
1005 /* Drop the previous xattr block. */
1006 if (bs->bh && bs->bh != new_bh)
Mingming Cao617ba132006-10-11 01:20:53 -07001007 ext4_xattr_release_block(handle, inode, bs->bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001008 error = 0;
1009
1010cleanup:
1011 if (ce)
Jan Kara7a2508e2016-02-22 22:35:22 -05001012 mb_cache_entry_put(ext4_mb_cache, ce);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001013 brelse(new_bh);
1014 if (!(bs->bh && s->base == bs->bh->b_data))
1015 kfree(s->base);
1016
1017 return error;
1018
1019cleanup_dquot:
Lukas Czerner1231b3a2013-02-18 12:12:07 -05001020 dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001021 goto cleanup;
1022
1023bad_block:
Theodore Ts'o24676da2010-05-16 21:00:00 -04001024 EXT4_ERROR_INODE(inode, "bad block %llu",
1025 EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001026 goto cleanup;
1027
1028#undef header
1029}
1030
Tao Ma879b3822012-12-05 10:28:46 -05001031int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
1032 struct ext4_xattr_ibody_find *is)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001033{
Mingming Cao617ba132006-10-11 01:20:53 -07001034 struct ext4_xattr_ibody_header *header;
1035 struct ext4_inode *raw_inode;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001036 int error;
1037
Mingming Cao617ba132006-10-11 01:20:53 -07001038 if (EXT4_I(inode)->i_extra_isize == 0)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001039 return 0;
Mingming Cao617ba132006-10-11 01:20:53 -07001040 raw_inode = ext4_raw_inode(&is->iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001041 header = IHDR(inode, raw_inode);
1042 is->s.base = is->s.first = IFIRST(header);
1043 is->s.here = is->s.first;
Mingming Cao617ba132006-10-11 01:20:53 -07001044 is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001045 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
Theodore Ts'o9e92f482016-03-22 16:13:15 -04001046 error = xattr_check_inode(inode, header, is->s.end);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001047 if (error)
1048 return error;
1049 /* Find the named attribute. */
Mingming Cao617ba132006-10-11 01:20:53 -07001050 error = ext4_xattr_find_entry(&is->s.here, i->name_index,
Eric Biggers6ba644b2017-04-30 00:01:02 -04001051 i->name, 0);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001052 if (error && error != -ENODATA)
1053 return error;
1054 is->s.not_found = error;
1055 }
1056 return 0;
1057}
1058
Tao Ma0d812f72012-12-10 14:06:02 -05001059int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode,
1060 struct ext4_xattr_info *i,
1061 struct ext4_xattr_ibody_find *is)
1062{
1063 struct ext4_xattr_ibody_header *header;
1064 struct ext4_xattr_search *s = &is->s;
1065 int error;
1066
1067 if (EXT4_I(inode)->i_extra_isize == 0)
1068 return -ENOSPC;
1069 error = ext4_xattr_set_entry(i, s);
1070 if (error) {
1071 if (error == -ENOSPC &&
1072 ext4_has_inline_data(inode)) {
1073 error = ext4_try_to_evict_inline_data(handle, inode,
1074 EXT4_XATTR_LEN(strlen(i->name) +
1075 EXT4_XATTR_SIZE(i->value_len)));
1076 if (error)
1077 return error;
1078 error = ext4_xattr_ibody_find(inode, i, is);
1079 if (error)
1080 return error;
1081 error = ext4_xattr_set_entry(i, s);
1082 }
1083 if (error)
1084 return error;
1085 }
1086 header = IHDR(inode, ext4_raw_inode(&is->iloc));
1087 if (!IS_LAST_ENTRY(s->first)) {
1088 header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
1089 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
1090 } else {
1091 header->h_magic = cpu_to_le32(0);
1092 ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
1093 }
1094 return 0;
1095}
1096
Eric Whitneyd5c8dab2016-11-14 21:56:48 -05001097static int ext4_xattr_ibody_set(struct inode *inode,
Tao Ma0d812f72012-12-10 14:06:02 -05001098 struct ext4_xattr_info *i,
1099 struct ext4_xattr_ibody_find *is)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001100{
Mingming Cao617ba132006-10-11 01:20:53 -07001101 struct ext4_xattr_ibody_header *header;
1102 struct ext4_xattr_search *s = &is->s;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001103 int error;
1104
Mingming Cao617ba132006-10-11 01:20:53 -07001105 if (EXT4_I(inode)->i_extra_isize == 0)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001106 return -ENOSPC;
Mingming Cao617ba132006-10-11 01:20:53 -07001107 error = ext4_xattr_set_entry(i, s);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001108 if (error)
1109 return error;
Mingming Cao617ba132006-10-11 01:20:53 -07001110 header = IHDR(inode, ext4_raw_inode(&is->iloc));
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001111 if (!IS_LAST_ENTRY(s->first)) {
Mingming Cao617ba132006-10-11 01:20:53 -07001112 header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001113 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001114 } else {
1115 header->h_magic = cpu_to_le32(0);
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001116 ext4_clear_inode_state(inode, EXT4_STATE_XATTR);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001117 }
1118 return 0;
1119}
1120
Jan Kara3fd16462016-02-22 22:43:04 -05001121static int ext4_xattr_value_same(struct ext4_xattr_search *s,
1122 struct ext4_xattr_info *i)
1123{
1124 void *value;
1125
1126 if (le32_to_cpu(s->here->e_value_size) != i->value_len)
1127 return 0;
1128 value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs);
1129 return !memcmp(value, i->value, i->value_len);
1130}
1131
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001132/*
Mingming Cao617ba132006-10-11 01:20:53 -07001133 * ext4_xattr_set_handle()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001134 *
Wang Sheng-Hui6e9510b2011-01-10 12:10:30 -05001135 * Create, replace or remove an extended attribute for this inode. Value
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001136 * is NULL to remove an existing extended attribute, and non-NULL to
1137 * either replace an existing extended attribute, or create a new extended
1138 * attribute. The flags XATTR_REPLACE and XATTR_CREATE
1139 * specify that an extended attribute must exist and must not exist
1140 * previous to the call, respectively.
1141 *
1142 * Returns 0, or a negative error number on failure.
1143 */
1144int
Mingming Cao617ba132006-10-11 01:20:53 -07001145ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001146 const char *name, const void *value, size_t value_len,
1147 int flags)
1148{
Mingming Cao617ba132006-10-11 01:20:53 -07001149 struct ext4_xattr_info i = {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001150 .name_index = name_index,
1151 .name = name,
1152 .value = value,
1153 .value_len = value_len,
1154
1155 };
Mingming Cao617ba132006-10-11 01:20:53 -07001156 struct ext4_xattr_ibody_find is = {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001157 .s = { .not_found = -ENODATA, },
1158 };
Mingming Cao617ba132006-10-11 01:20:53 -07001159 struct ext4_xattr_block_find bs = {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001160 .s = { .not_found = -ENODATA, },
1161 };
Theodore Ts'oc755e252017-01-11 21:50:46 -05001162 int no_expand;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001163 int error;
1164
1165 if (!name)
1166 return -EINVAL;
1167 if (strlen(name) > 255)
1168 return -ERANGE;
Theodore Ts'oc755e252017-01-11 21:50:46 -05001169 ext4_write_lock_xattr(inode, &no_expand);
Kalpak Shah4d20c682008-10-08 23:21:54 -04001170
Eric Sandeen66543612011-10-26 03:32:07 -04001171 error = ext4_reserve_inode_write(handle, inode, &is.iloc);
Eric Sandeen86ebfd02009-11-15 15:30:52 -05001172 if (error)
1173 goto cleanup;
1174
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001175 if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) {
Mingming Cao617ba132006-10-11 01:20:53 -07001176 struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc);
1177 memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
Theodore Ts'o19f5fb72010-01-24 14:34:07 -05001178 ext4_clear_inode_state(inode, EXT4_STATE_NEW);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001179 }
1180
Mingming Cao617ba132006-10-11 01:20:53 -07001181 error = ext4_xattr_ibody_find(inode, &i, &is);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001182 if (error)
1183 goto cleanup;
1184 if (is.s.not_found)
Mingming Cao617ba132006-10-11 01:20:53 -07001185 error = ext4_xattr_block_find(inode, &i, &bs);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001186 if (error)
1187 goto cleanup;
1188 if (is.s.not_found && bs.s.not_found) {
1189 error = -ENODATA;
1190 if (flags & XATTR_REPLACE)
1191 goto cleanup;
1192 error = 0;
1193 if (!value)
1194 goto cleanup;
1195 } else {
1196 error = -EEXIST;
1197 if (flags & XATTR_CREATE)
1198 goto cleanup;
1199 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001200 if (!value) {
1201 if (!is.s.not_found)
Eric Whitneyd5c8dab2016-11-14 21:56:48 -05001202 error = ext4_xattr_ibody_set(inode, &i, &is);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001203 else if (!bs.s.not_found)
Mingming Cao617ba132006-10-11 01:20:53 -07001204 error = ext4_xattr_block_set(handle, inode, &i, &bs);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001205 } else {
Jan Kara3fd16462016-02-22 22:43:04 -05001206 error = 0;
1207 /* Xattr value did not change? Save us some work and bail out */
1208 if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i))
1209 goto cleanup;
1210 if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i))
1211 goto cleanup;
1212
Eric Whitneyd5c8dab2016-11-14 21:56:48 -05001213 error = ext4_xattr_ibody_set(inode, &i, &is);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001214 if (!error && !bs.s.not_found) {
1215 i.value = NULL;
Mingming Cao617ba132006-10-11 01:20:53 -07001216 error = ext4_xattr_block_set(handle, inode, &i, &bs);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001217 } else if (error == -ENOSPC) {
Tiger Yang7e01c8e2008-05-14 16:05:47 -07001218 if (EXT4_I(inode)->i_file_acl && !bs.s.base) {
1219 error = ext4_xattr_block_find(inode, &i, &bs);
1220 if (error)
1221 goto cleanup;
1222 }
Mingming Cao617ba132006-10-11 01:20:53 -07001223 error = ext4_xattr_block_set(handle, inode, &i, &bs);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001224 if (error)
1225 goto cleanup;
1226 if (!is.s.not_found) {
1227 i.value = NULL;
Eric Whitneyd5c8dab2016-11-14 21:56:48 -05001228 error = ext4_xattr_ibody_set(inode, &i, &is);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001229 }
1230 }
1231 }
1232 if (!error) {
Mingming Cao617ba132006-10-11 01:20:53 -07001233 ext4_xattr_update_super_block(handle, inode->i_sb);
Deepa Dinamanieeca7ea2016-11-14 21:40:10 -05001234 inode->i_ctime = current_time(inode);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001235 if (!value)
Theodore Ts'oc755e252017-01-11 21:50:46 -05001236 no_expand = 0;
Mingming Cao617ba132006-10-11 01:20:53 -07001237 error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001238 /*
Mingming Cao617ba132006-10-11 01:20:53 -07001239 * The bh is consumed by ext4_mark_iloc_dirty, even with
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001240 * error != 0.
1241 */
1242 is.iloc.bh = NULL;
1243 if (IS_SYNC(inode))
Frank Mayhar03901312009-01-07 00:06:22 -05001244 ext4_handle_sync(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001245 }
1246
1247cleanup:
1248 brelse(is.iloc.bh);
1249 brelse(bs.bh);
Theodore Ts'oc755e252017-01-11 21:50:46 -05001250 ext4_write_unlock_xattr(inode, &no_expand);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001251 return error;
1252}
1253
1254/*
Mingming Cao617ba132006-10-11 01:20:53 -07001255 * ext4_xattr_set()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001256 *
Mingming Cao617ba132006-10-11 01:20:53 -07001257 * Like ext4_xattr_set_handle, but start from an inode. This extended
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001258 * attribute modification is a filesystem transaction by itself.
1259 *
1260 * Returns 0, or a negative error number on failure.
1261 */
1262int
Mingming Cao617ba132006-10-11 01:20:53 -07001263ext4_xattr_set(struct inode *inode, int name_index, const char *name,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001264 const void *value, size_t value_len, int flags)
1265{
1266 handle_t *handle;
1267 int error, retries = 0;
Theodore Ts'o95eaefb2013-02-09 15:23:03 -05001268 int credits = ext4_jbd2_credits_xattr(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001269
1270retry:
Theodore Ts'o9924a922013-02-08 21:59:22 -05001271 handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001272 if (IS_ERR(handle)) {
1273 error = PTR_ERR(handle);
1274 } else {
1275 int error2;
1276
Mingming Cao617ba132006-10-11 01:20:53 -07001277 error = ext4_xattr_set_handle(handle, inode, name_index, name,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001278 value, value_len, flags);
Mingming Cao617ba132006-10-11 01:20:53 -07001279 error2 = ext4_journal_stop(handle);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001280 if (error == -ENOSPC &&
Mingming Cao617ba132006-10-11 01:20:53 -07001281 ext4_should_retry_alloc(inode->i_sb, &retries))
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001282 goto retry;
1283 if (error == 0)
1284 error = error2;
1285 }
1286
1287 return error;
1288}
1289
1290/*
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001291 * Shift the EA entries in the inode to create space for the increased
1292 * i_extra_isize.
1293 */
1294static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry,
1295 int value_offs_shift, void *to,
Jan Kara94405712016-08-29 15:41:11 -04001296 void *from, size_t n)
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001297{
1298 struct ext4_xattr_entry *last = entry;
1299 int new_offs;
1300
Jan Kara94405712016-08-29 15:41:11 -04001301 /* We always shift xattr headers further thus offsets get lower */
1302 BUG_ON(value_offs_shift > 0);
1303
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001304 /* Adjust the value offsets of the entries */
1305 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
Jan Kara1cba4232016-08-29 15:40:11 -04001306 if (last->e_value_size) {
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001307 new_offs = le16_to_cpu(last->e_value_offs) +
1308 value_offs_shift;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001309 last->e_value_offs = cpu_to_le16(new_offs);
1310 }
1311 }
1312 /* Shift the entries by n bytes */
1313 memmove(to, from, n);
1314}
1315
1316/*
Jan Kara3f2571c2016-08-29 15:42:11 -04001317 * Move xattr pointed to by 'entry' from inode into external xattr block
1318 */
1319static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode,
1320 struct ext4_inode *raw_inode,
1321 struct ext4_xattr_entry *entry)
1322{
1323 struct ext4_xattr_ibody_find *is = NULL;
1324 struct ext4_xattr_block_find *bs = NULL;
1325 char *buffer = NULL, *b_entry_name = NULL;
1326 size_t value_offs, value_size;
1327 struct ext4_xattr_info i = {
1328 .value = NULL,
1329 .value_len = 0,
1330 .name_index = entry->e_name_index,
1331 };
1332 struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode);
1333 int error;
1334
1335 value_offs = le16_to_cpu(entry->e_value_offs);
1336 value_size = le32_to_cpu(entry->e_value_size);
1337
1338 is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS);
1339 bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS);
1340 buffer = kmalloc(value_size, GFP_NOFS);
1341 b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS);
1342 if (!is || !bs || !buffer || !b_entry_name) {
1343 error = -ENOMEM;
1344 goto out;
1345 }
1346
1347 is->s.not_found = -ENODATA;
1348 bs->s.not_found = -ENODATA;
1349 is->iloc.bh = NULL;
1350 bs->bh = NULL;
1351
1352 /* Save the entry name and the entry value */
1353 memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size);
1354 memcpy(b_entry_name, entry->e_name, entry->e_name_len);
1355 b_entry_name[entry->e_name_len] = '\0';
1356 i.name = b_entry_name;
1357
1358 error = ext4_get_inode_loc(inode, &is->iloc);
1359 if (error)
1360 goto out;
1361
1362 error = ext4_xattr_ibody_find(inode, &i, is);
1363 if (error)
1364 goto out;
1365
1366 /* Remove the chosen entry from the inode */
Eric Whitneyd5c8dab2016-11-14 21:56:48 -05001367 error = ext4_xattr_ibody_set(inode, &i, is);
Jan Kara3f2571c2016-08-29 15:42:11 -04001368 if (error)
1369 goto out;
1370
1371 i.name = b_entry_name;
1372 i.value = buffer;
1373 i.value_len = value_size;
1374 error = ext4_xattr_block_find(inode, &i, bs);
1375 if (error)
1376 goto out;
1377
1378 /* Add entry which was removed from the inode into the block */
1379 error = ext4_xattr_block_set(handle, inode, &i, bs);
1380 if (error)
1381 goto out;
1382 error = 0;
1383out:
1384 kfree(b_entry_name);
1385 kfree(buffer);
1386 if (is)
1387 brelse(is->iloc.bh);
1388 kfree(is);
1389 kfree(bs);
1390
1391 return error;
1392}
1393
Jan Karadfa20642016-08-29 15:44:11 -04001394static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode,
1395 struct ext4_inode *raw_inode,
1396 int isize_diff, size_t ifree,
1397 size_t bfree, int *total_ino)
1398{
1399 struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode);
1400 struct ext4_xattr_entry *small_entry;
1401 struct ext4_xattr_entry *entry;
1402 struct ext4_xattr_entry *last;
1403 unsigned int entry_size; /* EA entry size */
1404 unsigned int total_size; /* EA entry size + value size */
1405 unsigned int min_total_size;
1406 int error;
1407
1408 while (isize_diff > ifree) {
1409 entry = NULL;
1410 small_entry = NULL;
1411 min_total_size = ~0U;
1412 last = IFIRST(header);
1413 /* Find the entry best suited to be pushed into EA block */
1414 for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
1415 total_size =
1416 EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) +
1417 EXT4_XATTR_LEN(last->e_name_len);
1418 if (total_size <= bfree &&
1419 total_size < min_total_size) {
1420 if (total_size + ifree < isize_diff) {
1421 small_entry = last;
1422 } else {
1423 entry = last;
1424 min_total_size = total_size;
1425 }
1426 }
1427 }
1428
1429 if (entry == NULL) {
1430 if (small_entry == NULL)
1431 return -ENOSPC;
1432 entry = small_entry;
1433 }
1434
1435 entry_size = EXT4_XATTR_LEN(entry->e_name_len);
1436 total_size = entry_size +
1437 EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
1438 error = ext4_xattr_move_to_block(handle, inode, raw_inode,
1439 entry);
1440 if (error)
1441 return error;
1442
1443 *total_ino -= entry_size;
1444 ifree += total_size;
1445 bfree -= total_size;
1446 }
1447
1448 return 0;
1449}
1450
Jan Kara3f2571c2016-08-29 15:42:11 -04001451/*
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001452 * Expand an inode by new_extra_isize bytes when EAs are present.
1453 * Returns 0 on success or negative error number on failure.
1454 */
1455int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize,
1456 struct ext4_inode *raw_inode, handle_t *handle)
1457{
1458 struct ext4_xattr_ibody_header *header;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001459 struct buffer_head *bh = NULL;
Jan Karae3014d12016-08-29 15:38:11 -04001460 size_t min_offs;
1461 size_t ifree, bfree;
Theodore Ts'o7b1b2c12014-02-19 20:15:21 -05001462 int total_ino;
Jan Kara6e0cd082016-08-29 15:43:11 -04001463 void *base, *end;
Jan Karad0141192016-08-11 11:50:30 -04001464 int error = 0, tried_min_extra_isize = 0;
Aneesh Kumar K.Vac398492007-10-16 18:38:25 -04001465 int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize);
Jan Karad0141192016-08-11 11:50:30 -04001466 int isize_diff; /* How much do we need to grow i_extra_isize */
Theodore Ts'oc755e252017-01-11 21:50:46 -05001467 int no_expand;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001468
Theodore Ts'oc755e252017-01-11 21:50:46 -05001469 if (ext4_write_trylock_xattr(inode, &no_expand) == 0)
1470 return 0;
1471
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001472retry:
Jan Karad0141192016-08-11 11:50:30 -04001473 isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize;
Jan Kara2e81a4e2016-08-11 12:38:55 -04001474 if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
1475 goto out;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001476
1477 header = IHDR(inode, raw_inode);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001478
1479 /*
1480 * Check if enough free space is available in the inode to shift the
1481 * entries ahead by new_extra_isize.
1482 */
1483
Jan Kara6e0cd082016-08-29 15:43:11 -04001484 base = IFIRST(header);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001485 end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
1486 min_offs = end - base;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001487 total_ino = sizeof(struct ext4_xattr_ibody_header);
1488
Theodore Ts'o9e92f482016-03-22 16:13:15 -04001489 error = xattr_check_inode(inode, header, end);
1490 if (error)
1491 goto cleanup;
1492
Jan Kara6e0cd082016-08-29 15:43:11 -04001493 ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino);
Jan Karae3014d12016-08-29 15:38:11 -04001494 if (ifree >= isize_diff)
1495 goto shift;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001496
1497 /*
1498 * Enough free space isn't available in the inode, check if
1499 * EA block can hold new_extra_isize bytes.
1500 */
1501 if (EXT4_I(inode)->i_file_acl) {
1502 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
1503 error = -EIO;
1504 if (!bh)
1505 goto cleanup;
Darrick J. Wongcc8e94f2012-04-29 18:43:10 -04001506 if (ext4_xattr_check_block(inode, bh)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04001507 EXT4_ERROR_INODE(inode, "bad block %llu",
1508 EXT4_I(inode)->i_file_acl);
Darrick J. Wong6a797d22015-10-17 16:16:04 -04001509 error = -EFSCORRUPTED;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001510 goto cleanup;
1511 }
1512 base = BHDR(bh);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001513 end = bh->b_data + bh->b_size;
1514 min_offs = end - base;
Jan Kara6e0cd082016-08-29 15:43:11 -04001515 bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base,
1516 NULL);
Jan Karae3014d12016-08-29 15:38:11 -04001517 if (bfree + ifree < isize_diff) {
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001518 if (!tried_min_extra_isize && s_min_extra_isize) {
1519 tried_min_extra_isize++;
1520 new_extra_isize = s_min_extra_isize;
1521 brelse(bh);
1522 goto retry;
1523 }
Jan Karadfa20642016-08-29 15:44:11 -04001524 error = -ENOSPC;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001525 goto cleanup;
1526 }
1527 } else {
Jan Karae3014d12016-08-29 15:38:11 -04001528 bfree = inode->i_sb->s_blocksize;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001529 }
1530
Jan Karadfa20642016-08-29 15:44:11 -04001531 error = ext4_xattr_make_inode_space(handle, inode, raw_inode,
1532 isize_diff, ifree, bfree,
1533 &total_ino);
1534 if (error) {
1535 if (error == -ENOSPC && !tried_min_extra_isize &&
1536 s_min_extra_isize) {
1537 tried_min_extra_isize++;
1538 new_extra_isize = s_min_extra_isize;
1539 brelse(bh);
1540 goto retry;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001541 }
Jan Karadfa20642016-08-29 15:44:11 -04001542 goto cleanup;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001543 }
Jan Karae3014d12016-08-29 15:38:11 -04001544shift:
1545 /* Adjust the offsets and shift the remaining entries ahead */
Jan Kara6e0cd082016-08-29 15:43:11 -04001546 ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize
Jan Karae3014d12016-08-29 15:38:11 -04001547 - new_extra_isize, (void *)raw_inode +
1548 EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize,
Jan Kara94405712016-08-29 15:41:11 -04001549 (void *)header, total_ino);
Jan Karae3014d12016-08-29 15:38:11 -04001550 EXT4_I(inode)->i_extra_isize = new_extra_isize;
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001551 brelse(bh);
Jan Kara2e81a4e2016-08-11 12:38:55 -04001552out:
Theodore Ts'oc755e252017-01-11 21:50:46 -05001553 ext4_write_unlock_xattr(inode, &no_expand);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001554 return 0;
1555
1556cleanup:
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001557 brelse(bh);
Jan Kara2e81a4e2016-08-11 12:38:55 -04001558 /*
Theodore Ts'oc755e252017-01-11 21:50:46 -05001559 * Inode size expansion failed; don't try again
Jan Kara2e81a4e2016-08-11 12:38:55 -04001560 */
Theodore Ts'oc755e252017-01-11 21:50:46 -05001561 no_expand = 1;
1562 ext4_write_unlock_xattr(inode, &no_expand);
Kalpak Shah6dd4ee72007-07-18 09:19:57 -04001563 return error;
1564}
1565
1566
1567
1568/*
Mingming Cao617ba132006-10-11 01:20:53 -07001569 * ext4_xattr_delete_inode()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001570 *
1571 * Free extended attribute resources associated with this inode. This
1572 * is called immediately before an inode is freed. We have exclusive
1573 * access to the inode.
1574 */
1575void
Mingming Cao617ba132006-10-11 01:20:53 -07001576ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001577{
1578 struct buffer_head *bh = NULL;
1579
Mingming Cao617ba132006-10-11 01:20:53 -07001580 if (!EXT4_I(inode)->i_file_acl)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001581 goto cleanup;
Mingming Cao617ba132006-10-11 01:20:53 -07001582 bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001583 if (!bh) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04001584 EXT4_ERROR_INODE(inode, "block %llu read error",
1585 EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001586 goto cleanup;
1587 }
Mingming Cao617ba132006-10-11 01:20:53 -07001588 if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001589 BHDR(bh)->h_blocks != cpu_to_le32(1)) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04001590 EXT4_ERROR_INODE(inode, "bad block %llu",
1591 EXT4_I(inode)->i_file_acl);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001592 goto cleanup;
1593 }
Mingming Cao617ba132006-10-11 01:20:53 -07001594 ext4_xattr_release_block(handle, inode, bh);
1595 EXT4_I(inode)->i_file_acl = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001596
1597cleanup:
1598 brelse(bh);
1599}
1600
1601/*
Mingming Cao617ba132006-10-11 01:20:53 -07001602 * ext4_xattr_cache_insert()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001603 *
1604 * Create a new entry in the extended attribute cache, and insert
1605 * it unless such an entry is already in the cache.
1606 *
1607 * Returns 0, or a negative error number on failure.
1608 */
1609static void
Jan Kara7a2508e2016-02-22 22:35:22 -05001610ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001611{
Andreas Gruenbacher6048c642016-02-22 22:44:04 -05001612 struct ext4_xattr_header *header = BHDR(bh);
1613 __u32 hash = le32_to_cpu(header->h_hash);
1614 int reusable = le32_to_cpu(header->h_refcount) <
1615 EXT4_XATTR_REFCOUNT_MAX;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001616 int error;
1617
Jan Kara7a2508e2016-02-22 22:35:22 -05001618 error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash,
Andreas Gruenbacher6048c642016-02-22 22:44:04 -05001619 bh->b_blocknr, reusable);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001620 if (error) {
Jan Kara82939d72016-02-22 11:50:13 -05001621 if (error == -EBUSY)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001622 ea_bdebug(bh, "already in cache");
Jan Kara82939d72016-02-22 11:50:13 -05001623 } else
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001624 ea_bdebug(bh, "inserting [%x]", (int)hash);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001625}
1626
1627/*
Mingming Cao617ba132006-10-11 01:20:53 -07001628 * ext4_xattr_cmp()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001629 *
1630 * Compare two extended attribute blocks for equality.
1631 *
1632 * Returns 0 if the blocks are equal, 1 if they differ, and
1633 * a negative error number on errors.
1634 */
1635static int
Mingming Cao617ba132006-10-11 01:20:53 -07001636ext4_xattr_cmp(struct ext4_xattr_header *header1,
1637 struct ext4_xattr_header *header2)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001638{
Mingming Cao617ba132006-10-11 01:20:53 -07001639 struct ext4_xattr_entry *entry1, *entry2;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001640
1641 entry1 = ENTRY(header1+1);
1642 entry2 = ENTRY(header2+1);
1643 while (!IS_LAST_ENTRY(entry1)) {
1644 if (IS_LAST_ENTRY(entry2))
1645 return 1;
1646 if (entry1->e_hash != entry2->e_hash ||
1647 entry1->e_name_index != entry2->e_name_index ||
1648 entry1->e_name_len != entry2->e_name_len ||
1649 entry1->e_value_size != entry2->e_value_size ||
1650 memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
1651 return 1;
1652 if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
Darrick J. Wong6a797d22015-10-17 16:16:04 -04001653 return -EFSCORRUPTED;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001654 if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
1655 (char *)header2 + le16_to_cpu(entry2->e_value_offs),
1656 le32_to_cpu(entry1->e_value_size)))
1657 return 1;
1658
Mingming Cao617ba132006-10-11 01:20:53 -07001659 entry1 = EXT4_XATTR_NEXT(entry1);
1660 entry2 = EXT4_XATTR_NEXT(entry2);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001661 }
1662 if (!IS_LAST_ENTRY(entry2))
1663 return 1;
1664 return 0;
1665}
1666
1667/*
Mingming Cao617ba132006-10-11 01:20:53 -07001668 * ext4_xattr_cache_find()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001669 *
1670 * Find an identical extended attribute block.
1671 *
1672 * Returns a pointer to the block found, or NULL if such a block was
1673 * not found or an error occurred.
1674 */
1675static struct buffer_head *
Mingming Cao617ba132006-10-11 01:20:53 -07001676ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header,
Jan Kara7a2508e2016-02-22 22:35:22 -05001677 struct mb_cache_entry **pce)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001678{
1679 __u32 hash = le32_to_cpu(header->h_hash);
Jan Kara7a2508e2016-02-22 22:35:22 -05001680 struct mb_cache_entry *ce;
1681 struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001682
1683 if (!header->h_hash)
1684 return NULL; /* never share */
1685 ea_idebug(inode, "looking for cached blocks [%x]", (int)hash);
Jan Kara7a2508e2016-02-22 22:35:22 -05001686 ce = mb_cache_entry_find_first(ext4_mb_cache, hash);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001687 while (ce) {
1688 struct buffer_head *bh;
1689
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001690 bh = sb_bread(inode->i_sb, ce->e_block);
1691 if (!bh) {
Theodore Ts'o24676da2010-05-16 21:00:00 -04001692 EXT4_ERROR_INODE(inode, "block %lu read error",
1693 (unsigned long) ce->e_block);
Mingming Cao617ba132006-10-11 01:20:53 -07001694 } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001695 *pce = ce;
1696 return bh;
1697 }
1698 brelse(bh);
Jan Kara7a2508e2016-02-22 22:35:22 -05001699 ce = mb_cache_entry_find_next(ext4_mb_cache, ce);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001700 }
1701 return NULL;
1702}
1703
1704#define NAME_HASH_SHIFT 5
1705#define VALUE_HASH_SHIFT 16
1706
1707/*
Mingming Cao617ba132006-10-11 01:20:53 -07001708 * ext4_xattr_hash_entry()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001709 *
1710 * Compute the hash of an extended attribute.
1711 */
Mingming Cao617ba132006-10-11 01:20:53 -07001712static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header,
1713 struct ext4_xattr_entry *entry)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001714{
1715 __u32 hash = 0;
1716 char *name = entry->e_name;
1717 int n;
1718
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001719 for (n = 0; n < entry->e_name_len; n++) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001720 hash = (hash << NAME_HASH_SHIFT) ^
1721 (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
1722 *name++;
1723 }
1724
Jan Kara1cba4232016-08-29 15:40:11 -04001725 if (entry->e_value_size != 0) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001726 __le32 *value = (__le32 *)((char *)header +
1727 le16_to_cpu(entry->e_value_offs));
1728 for (n = (le32_to_cpu(entry->e_value_size) +
Mingming Cao617ba132006-10-11 01:20:53 -07001729 EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001730 hash = (hash << VALUE_HASH_SHIFT) ^
1731 (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
1732 le32_to_cpu(*value++);
1733 }
1734 }
1735 entry->e_hash = cpu_to_le32(hash);
1736}
1737
1738#undef NAME_HASH_SHIFT
1739#undef VALUE_HASH_SHIFT
1740
1741#define BLOCK_HASH_SHIFT 16
1742
1743/*
Mingming Cao617ba132006-10-11 01:20:53 -07001744 * ext4_xattr_rehash()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001745 *
1746 * Re-compute the extended attribute hash value after an entry has changed.
1747 */
Mingming Cao617ba132006-10-11 01:20:53 -07001748static void ext4_xattr_rehash(struct ext4_xattr_header *header,
1749 struct ext4_xattr_entry *entry)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001750{
Mingming Cao617ba132006-10-11 01:20:53 -07001751 struct ext4_xattr_entry *here;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001752 __u32 hash = 0;
1753
Mingming Cao617ba132006-10-11 01:20:53 -07001754 ext4_xattr_hash_entry(header, entry);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001755 here = ENTRY(header+1);
1756 while (!IS_LAST_ENTRY(here)) {
1757 if (!here->e_hash) {
1758 /* Block is not shared if an entry's hash value == 0 */
1759 hash = 0;
1760 break;
1761 }
1762 hash = (hash << BLOCK_HASH_SHIFT) ^
1763 (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
1764 le32_to_cpu(here->e_hash);
Mingming Cao617ba132006-10-11 01:20:53 -07001765 here = EXT4_XATTR_NEXT(here);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001766 }
1767 header->h_hash = cpu_to_le32(hash);
1768}
1769
1770#undef BLOCK_HASH_SHIFT
1771
T Makphaibulchoke9c191f72014-03-18 19:24:49 -04001772#define HASH_BUCKET_BITS 10
1773
Jan Kara7a2508e2016-02-22 22:35:22 -05001774struct mb_cache *
Jan Kara82939d72016-02-22 11:50:13 -05001775ext4_xattr_create_cache(void)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001776{
Jan Kara7a2508e2016-02-22 22:35:22 -05001777 return mb_cache_create(HASH_BUCKET_BITS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001778}
1779
Jan Kara7a2508e2016-02-22 22:35:22 -05001780void ext4_xattr_destroy_cache(struct mb_cache *cache)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001781{
T Makphaibulchoke9c191f72014-03-18 19:24:49 -04001782 if (cache)
Jan Kara7a2508e2016-02-22 22:35:22 -05001783 mb_cache_destroy(cache);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001784}
T Makphaibulchoke9c191f72014-03-18 19:24:49 -04001785