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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/reiserfs/xattr.c | |
3 | * | |
4 | * Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com> | |
5 | * | |
6 | */ | |
7 | ||
8 | /* | |
9 | * In order to implement EA/ACLs in a clean, backwards compatible manner, | |
10 | * they are implemented as files in a "private" directory. | |
11 | * Each EA is in it's own file, with the directory layout like so (/ is assumed | |
12 | * to be relative to fs root). Inside the /.reiserfs_priv/xattrs directory, | |
13 | * directories named using the capital-hex form of the objectid and | |
14 | * generation number are used. Inside each directory are individual files | |
15 | * named with the name of the extended attribute. | |
16 | * | |
17 | * So, for objectid 12648430, we could have: | |
18 | * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_access | |
19 | * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_default | |
20 | * /.reiserfs_priv/xattrs/C0FFEE.0/user.Content-Type | |
21 | * .. or similar. | |
22 | * | |
23 | * The file contents are the text of the EA. The size is known based on the | |
24 | * stat data describing the file. | |
25 | * | |
26 | * In the case of system.posix_acl_access and system.posix_acl_default, since | |
27 | * these are special cases for filesystem ACLs, they are interpreted by the | |
28 | * kernel, in addition, they are negatively and positively cached and attached | |
29 | * to the inode so that unnecessary lookups are avoided. | |
d984561b JM |
30 | * |
31 | * Locking works like so: | |
32 | * The xattr root (/.reiserfs_priv/xattrs) is protected by its i_mutex. | |
33 | * The xattr dir (/.reiserfs_priv/xattrs/<oid>.<gen>) is protected by | |
34 | * inode->xattr_sem. | |
35 | * The xattrs themselves are likewise protected by the xattr_sem. | |
1da177e4 LT |
36 | */ |
37 | ||
38 | #include <linux/reiserfs_fs.h> | |
16f7e0fe | 39 | #include <linux/capability.h> |
1da177e4 LT |
40 | #include <linux/dcache.h> |
41 | #include <linux/namei.h> | |
42 | #include <linux/errno.h> | |
43 | #include <linux/fs.h> | |
44 | #include <linux/file.h> | |
45 | #include <linux/pagemap.h> | |
46 | #include <linux/xattr.h> | |
47 | #include <linux/reiserfs_xattr.h> | |
48 | #include <linux/reiserfs_acl.h> | |
1da177e4 | 49 | #include <asm/uaccess.h> |
3277c39f | 50 | #include <net/checksum.h> |
1da177e4 LT |
51 | #include <linux/smp_lock.h> |
52 | #include <linux/stat.h> | |
6c17675e | 53 | #include <linux/quotaops.h> |
1da177e4 | 54 | |
1da177e4 LT |
55 | #define PRIVROOT_NAME ".reiserfs_priv" |
56 | #define XAROOT_NAME "xattrs" | |
57 | ||
6c17675e JM |
58 | /* Helpers for inode ops. We do this so that we don't have all the VFS |
59 | * overhead and also for proper i_mutex annotation. | |
60 | * dir->i_mutex must be held for all of them. */ | |
61 | static int xattr_create(struct inode *dir, struct dentry *dentry, int mode) | |
1da177e4 | 62 | { |
6c17675e JM |
63 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); |
64 | DQUOT_INIT(dir); | |
65 | return dir->i_op->create(dir, dentry, mode, NULL); | |
66 | } | |
bd4c625c | 67 | |
6c17675e JM |
68 | static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode) |
69 | { | |
70 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
71 | DQUOT_INIT(dir); | |
72 | return dir->i_op->mkdir(dir, dentry, mode); | |
73 | } | |
bd4c625c | 74 | |
6c17675e JM |
75 | /* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr |
76 | * mutation ops aren't called during rename or splace, which are the | |
77 | * only other users of I_MUTEX_CHILD. It violates the ordering, but that's | |
78 | * better than allocating another subclass just for this code. */ | |
79 | static int xattr_unlink(struct inode *dir, struct dentry *dentry) | |
80 | { | |
81 | int error; | |
82 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
83 | DQUOT_INIT(dir); | |
bd4c625c | 84 | |
6c17675e JM |
85 | mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD); |
86 | error = dir->i_op->unlink(dir, dentry); | |
87 | mutex_unlock(&dentry->d_inode->i_mutex); | |
88 | ||
89 | if (!error) | |
90 | d_delete(dentry); | |
91 | return error; | |
92 | } | |
93 | ||
94 | static int xattr_rmdir(struct inode *dir, struct dentry *dentry) | |
95 | { | |
96 | int error; | |
97 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
98 | DQUOT_INIT(dir); | |
99 | ||
100 | mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD); | |
101 | dentry_unhash(dentry); | |
102 | error = dir->i_op->rmdir(dir, dentry); | |
103 | if (!error) | |
104 | dentry->d_inode->i_flags |= S_DEAD; | |
105 | mutex_unlock(&dentry->d_inode->i_mutex); | |
106 | if (!error) | |
107 | d_delete(dentry); | |
108 | dput(dentry); | |
109 | ||
110 | return error; | |
111 | } | |
112 | ||
113 | ||
114 | #define xattr_may_create(flags) (!flags || flags & XATTR_CREATE) | |
115 | ||
116 | /* Returns and possibly creates the xattr dir. */ | |
117 | static struct dentry *lookup_or_create_dir(struct dentry *parent, | |
118 | const char *name, int flags) | |
119 | { | |
120 | struct dentry *dentry; | |
121 | BUG_ON(!parent); | |
122 | ||
123 | dentry = lookup_one_len(name, parent, strlen(name)); | |
124 | if (IS_ERR(dentry)) | |
125 | return dentry; | |
126 | else if (!dentry->d_inode) { | |
9b7f3755 | 127 | int err = -ENODATA; |
6c17675e JM |
128 | |
129 | if (xattr_may_create(flags)) { | |
130 | mutex_lock_nested(&parent->d_inode->i_mutex, | |
131 | I_MUTEX_XATTR); | |
132 | err = xattr_mkdir(parent->d_inode, dentry, 0700); | |
133 | mutex_unlock(&parent->d_inode->i_mutex); | |
134 | } | |
135 | ||
9b7f3755 | 136 | if (err) { |
6c17675e JM |
137 | dput(dentry); |
138 | dentry = ERR_PTR(err); | |
9b7f3755 | 139 | } |
bd4c625c | 140 | } |
bd4c625c | 141 | |
6c17675e JM |
142 | return dentry; |
143 | } | |
144 | ||
145 | static struct dentry *open_xa_root(struct super_block *sb, int flags) | |
146 | { | |
147 | struct dentry *privroot = REISERFS_SB(sb)->priv_root; | |
148 | if (!privroot) | |
149 | return ERR_PTR(-ENODATA); | |
150 | return lookup_or_create_dir(privroot, XAROOT_NAME, flags); | |
1da177e4 LT |
151 | } |
152 | ||
bd4c625c | 153 | static struct dentry *open_xa_dir(const struct inode *inode, int flags) |
1da177e4 | 154 | { |
bd4c625c LT |
155 | struct dentry *xaroot, *xadir; |
156 | char namebuf[17]; | |
157 | ||
6c17675e | 158 | xaroot = open_xa_root(inode->i_sb, flags); |
9b7f3755 | 159 | if (IS_ERR(xaroot)) |
bd4c625c | 160 | return xaroot; |
bd4c625c | 161 | |
bd4c625c LT |
162 | snprintf(namebuf, sizeof(namebuf), "%X.%X", |
163 | le32_to_cpu(INODE_PKEY(inode)->k_objectid), | |
164 | inode->i_generation); | |
bd4c625c | 165 | |
6c17675e | 166 | xadir = lookup_or_create_dir(xaroot, namebuf, flags); |
bd4c625c LT |
167 | dput(xaroot); |
168 | return xadir; | |
6c17675e | 169 | |
1da177e4 LT |
170 | } |
171 | ||
1da177e4 LT |
172 | /* |
173 | * this is very similar to fs/reiserfs/dir.c:reiserfs_readdir, but | |
174 | * we need to drop the path before calling the filldir struct. That | |
175 | * would be a big performance hit to the non-xattr case, so I've copied | |
176 | * the whole thing for now. --clm | |
177 | * | |
178 | * the big difference is that I go backwards through the directory, | |
179 | * and don't mess with f->f_pos, but the idea is the same. Do some | |
180 | * action on each and every entry in the directory. | |
181 | * | |
1b1dcc1b | 182 | * we're called with i_mutex held, so there are no worries about the directory |
1da177e4 LT |
183 | * changing underneath us. |
184 | */ | |
3227e14c | 185 | static int __xattr_readdir(struct inode *inode, void *dirent, filldir_t filldir) |
1da177e4 | 186 | { |
bd4c625c LT |
187 | struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */ |
188 | INITIALIZE_PATH(path_to_entry); | |
189 | struct buffer_head *bh; | |
190 | int entry_num; | |
191 | struct item_head *ih, tmp_ih; | |
192 | int search_res; | |
193 | char *local_buf; | |
194 | loff_t next_pos; | |
195 | char small_buf[32]; /* avoid kmalloc if we can */ | |
196 | struct reiserfs_de_head *deh; | |
197 | int d_reclen; | |
198 | char *d_name; | |
199 | off_t d_off; | |
200 | ino_t d_ino; | |
201 | struct reiserfs_dir_entry de; | |
202 | ||
203 | /* form key for search the next directory entry using f_pos field of | |
204 | file structure */ | |
205 | next_pos = max_reiserfs_offset(inode); | |
206 | ||
207 | while (1) { | |
208 | research: | |
209 | if (next_pos <= DOT_DOT_OFFSET) | |
210 | break; | |
211 | make_cpu_key(&pos_key, inode, next_pos, TYPE_DIRENTRY, 3); | |
212 | ||
213 | search_res = | |
214 | search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry, | |
215 | &de); | |
216 | if (search_res == IO_ERROR) { | |
217 | // FIXME: we could just skip part of directory which could | |
218 | // not be read | |
219 | pathrelse(&path_to_entry); | |
220 | return -EIO; | |
221 | } | |
1da177e4 | 222 | |
bd4c625c LT |
223 | if (search_res == NAME_NOT_FOUND) |
224 | de.de_entry_num--; | |
1da177e4 | 225 | |
bd4c625c LT |
226 | set_de_name_and_namelen(&de); |
227 | entry_num = de.de_entry_num; | |
228 | deh = &(de.de_deh[entry_num]); | |
1da177e4 | 229 | |
bd4c625c LT |
230 | bh = de.de_bh; |
231 | ih = de.de_ih; | |
1da177e4 | 232 | |
bd4c625c | 233 | if (!is_direntry_le_ih(ih)) { |
0030b645 JM |
234 | reiserfs_error(inode->i_sb, "jdm-20000", |
235 | "not direntry %h", ih); | |
bd4c625c LT |
236 | break; |
237 | } | |
238 | copy_item_head(&tmp_ih, ih); | |
1da177e4 | 239 | |
bd4c625c LT |
240 | /* we must have found item, that is item of this directory, */ |
241 | RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key), | |
242 | "vs-9000: found item %h does not match to dir we readdir %K", | |
243 | ih, &pos_key); | |
1da177e4 | 244 | |
bd4c625c LT |
245 | if (deh_offset(deh) <= DOT_DOT_OFFSET) { |
246 | break; | |
247 | } | |
1da177e4 | 248 | |
bd4c625c LT |
249 | /* look for the previous entry in the directory */ |
250 | next_pos = deh_offset(deh) - 1; | |
1da177e4 | 251 | |
bd4c625c LT |
252 | if (!de_visible(deh)) |
253 | /* it is hidden entry */ | |
254 | continue; | |
1da177e4 | 255 | |
bd4c625c LT |
256 | d_reclen = entry_length(bh, ih, entry_num); |
257 | d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh); | |
258 | d_off = deh_offset(deh); | |
259 | d_ino = deh_objectid(deh); | |
1da177e4 | 260 | |
bd4c625c LT |
261 | if (!d_name[d_reclen - 1]) |
262 | d_reclen = strlen(d_name); | |
1da177e4 | 263 | |
bd4c625c LT |
264 | if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)) { |
265 | /* too big to send back to VFS */ | |
266 | continue; | |
267 | } | |
1da177e4 | 268 | |
bd4c625c LT |
269 | /* Ignore the .reiserfs_priv entry */ |
270 | if (reiserfs_xattrs(inode->i_sb) && | |
271 | !old_format_only(inode->i_sb) && | |
272 | deh_objectid(deh) == | |
273 | le32_to_cpu(INODE_PKEY | |
274 | (REISERFS_SB(inode->i_sb)->priv_root->d_inode)-> | |
275 | k_objectid)) | |
276 | continue; | |
277 | ||
278 | if (d_reclen <= 32) { | |
279 | local_buf = small_buf; | |
280 | } else { | |
d739b42b | 281 | local_buf = kmalloc(d_reclen, GFP_NOFS); |
bd4c625c LT |
282 | if (!local_buf) { |
283 | pathrelse(&path_to_entry); | |
284 | return -ENOMEM; | |
285 | } | |
286 | if (item_moved(&tmp_ih, &path_to_entry)) { | |
d739b42b | 287 | kfree(local_buf); |
bd4c625c LT |
288 | |
289 | /* sigh, must retry. Do this same offset again */ | |
290 | next_pos = d_off; | |
291 | goto research; | |
292 | } | |
293 | } | |
1da177e4 | 294 | |
bd4c625c LT |
295 | // Note, that we copy name to user space via temporary |
296 | // buffer (local_buf) because filldir will block if | |
297 | // user space buffer is swapped out. At that time | |
298 | // entry can move to somewhere else | |
299 | memcpy(local_buf, d_name, d_reclen); | |
1da177e4 | 300 | |
bd4c625c LT |
301 | /* the filldir function might need to start transactions, |
302 | * or do who knows what. Release the path now that we've | |
303 | * copied all the important stuff out of the deh | |
304 | */ | |
305 | pathrelse(&path_to_entry); | |
306 | ||
307 | if (filldir(dirent, local_buf, d_reclen, d_off, d_ino, | |
308 | DT_UNKNOWN) < 0) { | |
309 | if (local_buf != small_buf) { | |
d739b42b | 310 | kfree(local_buf); |
bd4c625c LT |
311 | } |
312 | goto end; | |
313 | } | |
314 | if (local_buf != small_buf) { | |
d739b42b | 315 | kfree(local_buf); |
bd4c625c LT |
316 | } |
317 | } /* while */ | |
1da177e4 | 318 | |
bd4c625c LT |
319 | end: |
320 | pathrelse(&path_to_entry); | |
321 | return 0; | |
1da177e4 LT |
322 | } |
323 | ||
324 | /* | |
325 | * this could be done with dedicated readdir ops for the xattr files, | |
326 | * but I want to get something working asap | |
327 | * this is stolen from vfs_readdir | |
328 | * | |
329 | */ | |
330 | static | |
3227e14c | 331 | int xattr_readdir(struct inode *inode, filldir_t filler, void *buf) |
1da177e4 | 332 | { |
3227e14c | 333 | int res = -ENOENT; |
bd4c625c LT |
334 | if (!IS_DEADDIR(inode)) { |
335 | lock_kernel(); | |
3227e14c | 336 | res = __xattr_readdir(inode, buf, filler); |
bd4c625c LT |
337 | unlock_kernel(); |
338 | } | |
bd4c625c | 339 | return res; |
1da177e4 LT |
340 | } |
341 | ||
a72bdb1c JM |
342 | static int |
343 | __reiserfs_xattr_del(struct dentry *xadir, const char *name, int namelen) | |
344 | { | |
345 | struct dentry *dentry; | |
346 | struct inode *dir = xadir->d_inode; | |
347 | int err = 0; | |
348 | ||
349 | dentry = lookup_one_len(name, xadir, namelen); | |
350 | if (IS_ERR(dentry)) { | |
351 | err = PTR_ERR(dentry); | |
352 | goto out; | |
353 | } else if (!dentry->d_inode) { | |
354 | err = -ENODATA; | |
355 | goto out_file; | |
356 | } | |
357 | ||
358 | /* Skip directories.. */ | |
359 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
360 | goto out_file; | |
361 | ||
362 | if (!IS_PRIVATE(dentry->d_inode)) { | |
363 | reiserfs_error(dir->i_sb, "jdm-20003", | |
364 | "OID %08x [%.*s/%.*s] doesn't have " | |
365 | "priv flag set [parent is %sset].", | |
366 | le32_to_cpu(INODE_PKEY(dentry->d_inode)-> | |
367 | k_objectid), xadir->d_name.len, | |
368 | xadir->d_name.name, namelen, name, | |
369 | IS_PRIVATE(xadir->d_inode) ? "" : | |
370 | "not "); | |
371 | dput(dentry); | |
372 | return -EIO; | |
373 | } | |
374 | ||
6c17675e | 375 | err = xattr_unlink(dir, dentry); |
a72bdb1c JM |
376 | |
377 | out_file: | |
378 | dput(dentry); | |
379 | ||
380 | out: | |
381 | return err; | |
382 | } | |
383 | ||
384 | /* The following are side effects of other operations that aren't explicitly | |
385 | * modifying extended attributes. This includes operations such as permissions | |
386 | * or ownership changes, object deletions, etc. */ | |
387 | ||
388 | static int | |
389 | reiserfs_delete_xattrs_filler(void *buf, const char *name, int namelen, | |
390 | loff_t offset, u64 ino, unsigned int d_type) | |
391 | { | |
392 | struct dentry *xadir = (struct dentry *)buf; | |
393 | ||
394 | return __reiserfs_xattr_del(xadir, name, namelen); | |
395 | ||
396 | } | |
397 | ||
398 | /* This is called w/ inode->i_mutex downed */ | |
399 | int reiserfs_delete_xattrs(struct inode *inode) | |
400 | { | |
a72bdb1c | 401 | int err = 0; |
d984561b JM |
402 | struct dentry *dir, *root; |
403 | struct reiserfs_transaction_handle th; | |
404 | int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 + | |
405 | 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb); | |
a72bdb1c JM |
406 | |
407 | /* Skip out, an xattr has no xattrs associated with it */ | |
408 | if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1) | |
409 | return 0; | |
410 | ||
6c17675e | 411 | dir = open_xa_dir(inode, XATTR_REPLACE); |
a72bdb1c JM |
412 | if (IS_ERR(dir)) { |
413 | err = PTR_ERR(dir); | |
414 | goto out; | |
415 | } else if (!dir->d_inode) { | |
416 | dput(dir); | |
417 | return 0; | |
418 | } | |
419 | ||
6c17675e | 420 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
a72bdb1c | 421 | err = xattr_readdir(dir->d_inode, reiserfs_delete_xattrs_filler, dir); |
6c17675e JM |
422 | mutex_unlock(&dir->d_inode->i_mutex); |
423 | if (err) | |
a72bdb1c | 424 | goto out_dir; |
a72bdb1c | 425 | |
d984561b JM |
426 | /* We start a transaction here to avoid a ABBA situation |
427 | * between the xattr root's i_mutex and the journal lock. | |
428 | * Inode creation will inherit an ACL, which requires a | |
429 | * lookup. The lookup locks the xattr root i_mutex with a | |
430 | * transaction open. Inode deletion takes teh xattr root | |
431 | * i_mutex to delete the directory and then starts a | |
432 | * transaction inside it. Boom. This doesn't incur much | |
433 | * additional overhead since the reiserfs_rmdir transaction | |
434 | * will just nest inside the outer transaction. */ | |
435 | err = journal_begin(&th, inode->i_sb, blocks); | |
436 | if (!err) { | |
437 | int jerror; | |
438 | root = dget(dir->d_parent); | |
6c17675e JM |
439 | mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_XATTR); |
440 | err = xattr_rmdir(root->d_inode, dir); | |
d984561b | 441 | jerror = journal_end(&th, inode->i_sb, blocks); |
6c17675e | 442 | mutex_unlock(&root->d_inode->i_mutex); |
a72bdb1c | 443 | dput(root); |
d984561b JM |
444 | |
445 | err = jerror ?: err; | |
a72bdb1c | 446 | } |
a72bdb1c JM |
447 | |
448 | out_dir: | |
449 | dput(dir); | |
450 | ||
451 | out: | |
452 | if (!err) | |
453 | REISERFS_I(inode)->i_flags = | |
454 | REISERFS_I(inode)->i_flags & ~i_has_xattr_dir; | |
d984561b JM |
455 | else |
456 | reiserfs_warning(inode->i_sb, "jdm-20004", | |
457 | "Couldn't remove all xattrs (%d)\n", err); | |
a72bdb1c JM |
458 | return err; |
459 | } | |
460 | ||
461 | struct reiserfs_chown_buf { | |
462 | struct inode *inode; | |
463 | struct dentry *xadir; | |
464 | struct iattr *attrs; | |
465 | }; | |
466 | ||
467 | /* XXX: If there is a better way to do this, I'd love to hear about it */ | |
468 | static int | |
469 | reiserfs_chown_xattrs_filler(void *buf, const char *name, int namelen, | |
470 | loff_t offset, u64 ino, unsigned int d_type) | |
471 | { | |
472 | struct reiserfs_chown_buf *chown_buf = (struct reiserfs_chown_buf *)buf; | |
473 | struct dentry *xafile, *xadir = chown_buf->xadir; | |
474 | struct iattr *attrs = chown_buf->attrs; | |
475 | int err = 0; | |
476 | ||
477 | xafile = lookup_one_len(name, xadir, namelen); | |
478 | if (IS_ERR(xafile)) | |
479 | return PTR_ERR(xafile); | |
480 | else if (!xafile->d_inode) { | |
481 | dput(xafile); | |
482 | return -ENODATA; | |
483 | } | |
484 | ||
6c17675e JM |
485 | if (!S_ISDIR(xafile->d_inode->i_mode)) { |
486 | mutex_lock_nested(&xafile->d_inode->i_mutex, I_MUTEX_CHILD); | |
a72bdb1c | 487 | err = notify_change(xafile, attrs); |
6c17675e JM |
488 | mutex_unlock(&xafile->d_inode->i_mutex); |
489 | } | |
a72bdb1c JM |
490 | dput(xafile); |
491 | ||
492 | return err; | |
493 | } | |
494 | ||
495 | int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs) | |
496 | { | |
497 | struct dentry *dir; | |
498 | int err = 0; | |
499 | struct reiserfs_chown_buf buf; | |
500 | unsigned int ia_valid = attrs->ia_valid; | |
501 | ||
502 | /* Skip out, an xattr has no xattrs associated with it */ | |
503 | if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1) | |
504 | return 0; | |
505 | ||
6c17675e | 506 | dir = open_xa_dir(inode, XATTR_REPLACE); |
a72bdb1c JM |
507 | if (IS_ERR(dir)) { |
508 | if (PTR_ERR(dir) != -ENODATA) | |
509 | err = PTR_ERR(dir); | |
510 | goto out; | |
6c17675e JM |
511 | } else if (!dir->d_inode) |
512 | goto out_dir; | |
a72bdb1c JM |
513 | |
514 | attrs->ia_valid &= (ATTR_UID | ATTR_GID | ATTR_CTIME); | |
515 | buf.xadir = dir; | |
516 | buf.attrs = attrs; | |
517 | buf.inode = inode; | |
518 | ||
6c17675e | 519 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
a72bdb1c | 520 | err = xattr_readdir(dir->d_inode, reiserfs_chown_xattrs_filler, &buf); |
a72bdb1c | 521 | |
6c17675e JM |
522 | if (!err) |
523 | err = notify_change(dir, attrs); | |
524 | mutex_unlock(&dir->d_inode->i_mutex); | |
a72bdb1c | 525 | |
6c17675e | 526 | attrs->ia_valid = ia_valid; |
a72bdb1c JM |
527 | out_dir: |
528 | dput(dir); | |
a72bdb1c | 529 | out: |
a72bdb1c JM |
530 | return err; |
531 | } | |
532 | ||
533 | #ifdef CONFIG_REISERFS_FS_XATTR | |
534 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char | |
535 | *prefix); | |
536 | ||
537 | /* Returns a dentry corresponding to a specific extended attribute file | |
538 | * for the inode. If flags allow, the file is created. Otherwise, a | |
539 | * valid or negative dentry, or an error is returned. */ | |
540 | static struct dentry *get_xa_file_dentry(const struct inode *inode, | |
541 | const char *name, int flags) | |
542 | { | |
543 | struct dentry *xadir, *xafile; | |
544 | int err = 0; | |
545 | ||
546 | xadir = open_xa_dir(inode, flags); | |
6c17675e | 547 | if (IS_ERR(xadir)) |
a72bdb1c | 548 | return ERR_CAST(xadir); |
a72bdb1c JM |
549 | |
550 | xafile = lookup_one_len(name, xadir, strlen(name)); | |
551 | if (IS_ERR(xafile)) { | |
6c17675e JM |
552 | err = PTR_ERR(xafile); |
553 | goto out; | |
a72bdb1c JM |
554 | } |
555 | ||
6c17675e JM |
556 | if (xafile->d_inode && (flags & XATTR_CREATE)) |
557 | err = -EEXIST; | |
a72bdb1c | 558 | |
6c17675e JM |
559 | if (!xafile->d_inode) { |
560 | err = -ENODATA; | |
561 | if (xattr_may_create(flags)) { | |
562 | mutex_lock_nested(&xadir->d_inode->i_mutex, | |
563 | I_MUTEX_XATTR); | |
564 | err = xattr_create(xadir->d_inode, xafile, | |
565 | 0700|S_IFREG); | |
566 | mutex_unlock(&xadir->d_inode->i_mutex); | |
a72bdb1c JM |
567 | } |
568 | } | |
569 | ||
6c17675e JM |
570 | if (err) |
571 | dput(xafile); | |
a72bdb1c JM |
572 | out: |
573 | dput(xadir); | |
574 | if (err) | |
6c17675e | 575 | return ERR_PTR(err); |
a72bdb1c JM |
576 | return xafile; |
577 | } | |
578 | ||
1da177e4 | 579 | /* Internal operations on file data */ |
bd4c625c | 580 | static inline void reiserfs_put_page(struct page *page) |
1da177e4 | 581 | { |
bd4c625c LT |
582 | kunmap(page); |
583 | page_cache_release(page); | |
1da177e4 LT |
584 | } |
585 | ||
ec6ea56b | 586 | static struct page *reiserfs_get_page(struct inode *dir, size_t n) |
1da177e4 | 587 | { |
bd4c625c LT |
588 | struct address_space *mapping = dir->i_mapping; |
589 | struct page *page; | |
590 | /* We can deadlock if we try to free dentries, | |
591 | and an unlink/rmdir has just occured - GFP_NOFS avoids this */ | |
c4cdd038 | 592 | mapping_set_gfp_mask(mapping, GFP_NOFS); |
ec6ea56b | 593 | page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL); |
bd4c625c | 594 | if (!IS_ERR(page)) { |
bd4c625c | 595 | kmap(page); |
bd4c625c LT |
596 | if (PageError(page)) |
597 | goto fail; | |
598 | } | |
599 | return page; | |
600 | ||
601 | fail: | |
602 | reiserfs_put_page(page); | |
603 | return ERR_PTR(-EIO); | |
1da177e4 LT |
604 | } |
605 | ||
bd4c625c | 606 | static inline __u32 xattr_hash(const char *msg, int len) |
1da177e4 | 607 | { |
bd4c625c | 608 | return csum_partial(msg, len, 0); |
1da177e4 LT |
609 | } |
610 | ||
ba9d8cec VS |
611 | int reiserfs_commit_write(struct file *f, struct page *page, |
612 | unsigned from, unsigned to); | |
613 | int reiserfs_prepare_write(struct file *f, struct page *page, | |
614 | unsigned from, unsigned to); | |
615 | ||
616 | ||
1da177e4 LT |
617 | /* Generic extended attribute operations that can be used by xa plugins */ |
618 | ||
619 | /* | |
1b1dcc1b | 620 | * inode->i_mutex: down |
1da177e4 LT |
621 | */ |
622 | int | |
bd4c625c LT |
623 | reiserfs_xattr_set(struct inode *inode, const char *name, const void *buffer, |
624 | size_t buffer_size, int flags) | |
1da177e4 | 625 | { |
bd4c625c | 626 | int err = 0; |
3227e14c | 627 | struct dentry *dentry; |
bd4c625c LT |
628 | struct page *page; |
629 | char *data; | |
bd4c625c LT |
630 | size_t file_pos = 0; |
631 | size_t buffer_pos = 0; | |
bd4c625c LT |
632 | struct iattr newattrs; |
633 | __u32 xahash = 0; | |
634 | ||
bd4c625c LT |
635 | if (get_inode_sd_version(inode) == STAT_DATA_V1) |
636 | return -EOPNOTSUPP; | |
637 | ||
638 | /* Empty xattrs are ok, they're just empty files, no hash */ | |
639 | if (buffer && buffer_size) | |
640 | xahash = xattr_hash(buffer, buffer_size); | |
641 | ||
3227e14c JM |
642 | dentry = get_xa_file_dentry(inode, name, flags); |
643 | if (IS_ERR(dentry)) { | |
644 | err = PTR_ERR(dentry); | |
bd4c625c LT |
645 | goto out; |
646 | } | |
647 | ||
bd4c625c LT |
648 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; |
649 | ||
bd4c625c LT |
650 | /* Resize it so we're ok to write there */ |
651 | newattrs.ia_size = buffer_size; | |
652 | newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME; | |
f437c529 | 653 | mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR); |
3227e14c | 654 | err = notify_change(dentry, &newattrs); |
6c17675e | 655 | mutex_unlock(&dentry->d_inode->i_mutex); |
bd4c625c LT |
656 | if (err) |
657 | goto out_filp; | |
658 | ||
bd4c625c LT |
659 | while (buffer_pos < buffer_size || buffer_pos == 0) { |
660 | size_t chunk; | |
661 | size_t skip = 0; | |
662 | size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1)); | |
663 | if (buffer_size - buffer_pos > PAGE_CACHE_SIZE) | |
664 | chunk = PAGE_CACHE_SIZE; | |
665 | else | |
666 | chunk = buffer_size - buffer_pos; | |
667 | ||
ec6ea56b | 668 | page = reiserfs_get_page(dentry->d_inode, file_pos); |
bd4c625c LT |
669 | if (IS_ERR(page)) { |
670 | err = PTR_ERR(page); | |
671 | goto out_filp; | |
672 | } | |
673 | ||
674 | lock_page(page); | |
675 | data = page_address(page); | |
676 | ||
677 | if (file_pos == 0) { | |
678 | struct reiserfs_xattr_header *rxh; | |
679 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
680 | if (chunk + skip > PAGE_CACHE_SIZE) | |
681 | chunk = PAGE_CACHE_SIZE - skip; | |
682 | rxh = (struct reiserfs_xattr_header *)data; | |
683 | rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC); | |
684 | rxh->h_hash = cpu_to_le32(xahash); | |
685 | } | |
686 | ||
3227e14c | 687 | err = reiserfs_prepare_write(NULL, page, page_offset, |
ba9d8cec | 688 | page_offset + chunk + skip); |
bd4c625c LT |
689 | if (!err) { |
690 | if (buffer) | |
691 | memcpy(data + skip, buffer + buffer_pos, chunk); | |
3227e14c JM |
692 | err = reiserfs_commit_write(NULL, page, page_offset, |
693 | page_offset + chunk + | |
694 | skip); | |
bd4c625c LT |
695 | } |
696 | unlock_page(page); | |
697 | reiserfs_put_page(page); | |
698 | buffer_pos += chunk; | |
699 | file_pos += chunk; | |
700 | skip = 0; | |
701 | if (err || buffer_size == 0 || !buffer) | |
702 | break; | |
703 | } | |
704 | ||
705 | /* We can't mark the inode dirty if it's not hashed. This is the case | |
706 | * when we're inheriting the default ACL. If we dirty it, the inode | |
707 | * gets marked dirty, but won't (ever) make it onto the dirty list until | |
708 | * it's synced explicitly to clear I_DIRTY. This is bad. */ | |
709 | if (!hlist_unhashed(&inode->i_hash)) { | |
710 | inode->i_ctime = CURRENT_TIME_SEC; | |
711 | mark_inode_dirty(inode); | |
1da177e4 | 712 | } |
bd4c625c LT |
713 | |
714 | out_filp: | |
3227e14c | 715 | dput(dentry); |
bd4c625c LT |
716 | |
717 | out: | |
718 | return err; | |
1da177e4 LT |
719 | } |
720 | ||
721 | /* | |
1b1dcc1b | 722 | * inode->i_mutex: down |
1da177e4 LT |
723 | */ |
724 | int | |
bd4c625c LT |
725 | reiserfs_xattr_get(const struct inode *inode, const char *name, void *buffer, |
726 | size_t buffer_size) | |
1da177e4 | 727 | { |
bd4c625c | 728 | ssize_t err = 0; |
3227e14c | 729 | struct dentry *dentry; |
bd4c625c LT |
730 | size_t isize; |
731 | size_t file_pos = 0; | |
732 | size_t buffer_pos = 0; | |
733 | struct page *page; | |
bd4c625c LT |
734 | __u32 hash = 0; |
735 | ||
736 | if (name == NULL) | |
737 | return -EINVAL; | |
738 | ||
739 | /* We can't have xattrs attached to v1 items since they don't have | |
740 | * generation numbers */ | |
741 | if (get_inode_sd_version(inode) == STAT_DATA_V1) | |
742 | return -EOPNOTSUPP; | |
743 | ||
6c17675e | 744 | dentry = get_xa_file_dentry(inode, name, XATTR_REPLACE); |
3227e14c JM |
745 | if (IS_ERR(dentry)) { |
746 | err = PTR_ERR(dentry); | |
bd4c625c LT |
747 | goto out; |
748 | } | |
749 | ||
d984561b JM |
750 | /* protect against concurrent access. xattrs are backed by |
751 | * regular files, but they're not regular files. The updates | |
752 | * must be atomic from the perspective of the user. */ | |
753 | mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR); | |
754 | ||
f437c529 | 755 | isize = i_size_read(dentry->d_inode); |
bd4c625c LT |
756 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; |
757 | ||
758 | /* Just return the size needed */ | |
759 | if (buffer == NULL) { | |
760 | err = isize - sizeof(struct reiserfs_xattr_header); | |
761 | goto out_dput; | |
762 | } | |
763 | ||
764 | if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) { | |
765 | err = -ERANGE; | |
766 | goto out_dput; | |
767 | } | |
768 | ||
a72bdb1c JM |
769 | while (file_pos < isize) { |
770 | size_t chunk; | |
771 | char *data; | |
772 | size_t skip = 0; | |
773 | if (isize - file_pos > PAGE_CACHE_SIZE) | |
774 | chunk = PAGE_CACHE_SIZE; | |
775 | else | |
776 | chunk = isize - file_pos; | |
1da177e4 | 777 | |
a72bdb1c JM |
778 | page = reiserfs_get_page(dentry->d_inode, file_pos); |
779 | if (IS_ERR(page)) { | |
780 | err = PTR_ERR(page); | |
781 | goto out_dput; | |
782 | } | |
1da177e4 | 783 | |
a72bdb1c JM |
784 | lock_page(page); |
785 | data = page_address(page); | |
786 | if (file_pos == 0) { | |
787 | struct reiserfs_xattr_header *rxh = | |
788 | (struct reiserfs_xattr_header *)data; | |
789 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
790 | chunk -= skip; | |
791 | /* Magic doesn't match up.. */ | |
792 | if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) { | |
793 | unlock_page(page); | |
794 | reiserfs_put_page(page); | |
795 | reiserfs_warning(inode->i_sb, "jdm-20001", | |
796 | "Invalid magic for xattr (%s) " | |
797 | "associated with %k", name, | |
798 | INODE_PKEY(inode)); | |
799 | err = -EIO; | |
800 | goto out_dput; | |
801 | } | |
802 | hash = le32_to_cpu(rxh->h_hash); | |
803 | } | |
804 | memcpy(buffer + buffer_pos, data + skip, chunk); | |
805 | unlock_page(page); | |
806 | reiserfs_put_page(page); | |
807 | file_pos += chunk; | |
808 | buffer_pos += chunk; | |
809 | skip = 0; | |
810 | } | |
811 | err = isize - sizeof(struct reiserfs_xattr_header); | |
bd4c625c | 812 | |
a72bdb1c JM |
813 | if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) != |
814 | hash) { | |
815 | reiserfs_warning(inode->i_sb, "jdm-20002", | |
816 | "Invalid hash for xattr (%s) associated " | |
817 | "with %k", name, INODE_PKEY(inode)); | |
818 | err = -EIO; | |
bd4c625c LT |
819 | } |
820 | ||
a72bdb1c | 821 | out_dput: |
d984561b | 822 | mutex_unlock(&dentry->d_inode->i_mutex); |
a72bdb1c | 823 | dput(dentry); |
bd4c625c | 824 | |
a72bdb1c | 825 | out: |
bd4c625c | 826 | return err; |
1da177e4 LT |
827 | } |
828 | ||
a72bdb1c | 829 | int reiserfs_xattr_del(struct inode *inode, const char *name) |
1da177e4 | 830 | { |
bd4c625c | 831 | struct dentry *dir; |
a72bdb1c | 832 | int err; |
bd4c625c | 833 | |
6c17675e | 834 | dir = open_xa_dir(inode, XATTR_REPLACE); |
bd4c625c | 835 | if (IS_ERR(dir)) { |
a72bdb1c | 836 | err = PTR_ERR(dir); |
bd4c625c LT |
837 | goto out; |
838 | } | |
839 | ||
6c17675e | 840 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
a72bdb1c | 841 | err = __reiserfs_xattr_del(dir, name, strlen(name)); |
6c17675e | 842 | mutex_unlock(&dir->d_inode->i_mutex); |
a72bdb1c | 843 | dput(dir); |
bd4c625c | 844 | |
a72bdb1c JM |
845 | if (!err) { |
846 | inode->i_ctime = CURRENT_TIME_SEC; | |
847 | mark_inode_dirty(inode); | |
bd4c625c LT |
848 | } |
849 | ||
bd4c625c | 850 | out: |
bd4c625c LT |
851 | return err; |
852 | } | |
1da177e4 LT |
853 | |
854 | /* Actual operations that are exported to VFS-land */ | |
855 | ||
6c17675e | 856 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char *); |
1da177e4 LT |
857 | /* |
858 | * Inode operation getxattr() | |
1da177e4 LT |
859 | */ |
860 | ssize_t | |
bd4c625c LT |
861 | reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer, |
862 | size_t size) | |
1da177e4 | 863 | { |
bd4c625c LT |
864 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
865 | int err; | |
866 | ||
867 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
868 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
869 | return -EOPNOTSUPP; | |
870 | ||
871 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
bd4c625c | 872 | err = xah->get(dentry->d_inode, name, buffer, size); |
bd4c625c LT |
873 | reiserfs_read_unlock_xattr_i(dentry->d_inode); |
874 | return err; | |
1da177e4 LT |
875 | } |
876 | ||
1da177e4 LT |
877 | /* |
878 | * Inode operation setxattr() | |
879 | * | |
1b1dcc1b | 880 | * dentry->d_inode->i_mutex down |
1da177e4 LT |
881 | */ |
882 | int | |
bd4c625c LT |
883 | reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
884 | size_t size, int flags) | |
1da177e4 | 885 | { |
bd4c625c LT |
886 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
887 | int err; | |
bd4c625c LT |
888 | |
889 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
890 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
891 | return -EOPNOTSUPP; | |
892 | ||
bd4c625c | 893 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
bd4c625c | 894 | err = xah->set(dentry->d_inode, name, value, size, flags); |
bd4c625c LT |
895 | reiserfs_write_unlock_xattr_i(dentry->d_inode); |
896 | return err; | |
1da177e4 LT |
897 | } |
898 | ||
899 | /* | |
900 | * Inode operation removexattr() | |
901 | * | |
1b1dcc1b | 902 | * dentry->d_inode->i_mutex down |
1da177e4 | 903 | */ |
bd4c625c | 904 | int reiserfs_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 905 | { |
bd4c625c LT |
906 | int err; |
907 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); | |
1da177e4 | 908 | |
bd4c625c LT |
909 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || |
910 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
911 | return -EOPNOTSUPP; | |
1da177e4 | 912 | |
bd4c625c | 913 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
bd4c625c LT |
914 | /* Deletion pre-operation */ |
915 | if (xah->del) { | |
916 | err = xah->del(dentry->d_inode, name); | |
917 | if (err) | |
918 | goto out; | |
919 | } | |
1da177e4 | 920 | |
bd4c625c | 921 | err = reiserfs_xattr_del(dentry->d_inode, name); |
1da177e4 | 922 | |
bd4c625c LT |
923 | dentry->d_inode->i_ctime = CURRENT_TIME_SEC; |
924 | mark_inode_dirty(dentry->d_inode); | |
1da177e4 | 925 | |
bd4c625c | 926 | out: |
bd4c625c LT |
927 | reiserfs_write_unlock_xattr_i(dentry->d_inode); |
928 | return err; | |
1da177e4 LT |
929 | } |
930 | ||
1da177e4 LT |
931 | /* This is what filldir will use: |
932 | * r_pos will always contain the amount of space required for the entire | |
933 | * list. If r_pos becomes larger than r_size, we need more space and we | |
934 | * return an error indicating this. If r_pos is less than r_size, then we've | |
935 | * filled the buffer successfully and we return success */ | |
936 | struct reiserfs_listxattr_buf { | |
bd4c625c LT |
937 | int r_pos; |
938 | int r_size; | |
939 | char *r_buf; | |
940 | struct inode *r_inode; | |
1da177e4 LT |
941 | }; |
942 | ||
943 | static int | |
bd4c625c | 944 | reiserfs_listxattr_filler(void *buf, const char *name, int namelen, |
afefdbb2 | 945 | loff_t offset, u64 ino, unsigned int d_type) |
1da177e4 | 946 | { |
bd4c625c LT |
947 | struct reiserfs_listxattr_buf *b = (struct reiserfs_listxattr_buf *)buf; |
948 | int len = 0; | |
949 | if (name[0] != '.' | |
950 | || (namelen != 1 && (name[1] != '.' || namelen != 2))) { | |
951 | struct reiserfs_xattr_handler *xah = | |
952 | find_xattr_handler_prefix(name); | |
953 | if (!xah) | |
954 | return 0; /* Unsupported xattr name, skip it */ | |
955 | ||
956 | /* We call ->list() twice because the operation isn't required to just | |
957 | * return the name back - we want to make sure we have enough space */ | |
958 | len += xah->list(b->r_inode, name, namelen, NULL); | |
959 | ||
960 | if (len) { | |
961 | if (b->r_pos + len + 1 <= b->r_size) { | |
962 | char *p = b->r_buf + b->r_pos; | |
963 | p += xah->list(b->r_inode, name, namelen, p); | |
964 | *p++ = '\0'; | |
965 | } | |
966 | b->r_pos += len + 1; | |
967 | } | |
968 | } | |
969 | ||
970 | return 0; | |
1da177e4 | 971 | } |
bd4c625c | 972 | |
1da177e4 LT |
973 | /* |
974 | * Inode operation listxattr() | |
1da177e4 | 975 | */ |
bd4c625c | 976 | ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size) |
1da177e4 | 977 | { |
bd4c625c LT |
978 | struct dentry *dir; |
979 | int err = 0; | |
980 | struct reiserfs_listxattr_buf buf; | |
981 | ||
982 | if (!dentry->d_inode) | |
983 | return -EINVAL; | |
984 | ||
985 | if (!reiserfs_xattrs(dentry->d_sb) || | |
986 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
987 | return -EOPNOTSUPP; | |
988 | ||
989 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
6c17675e | 990 | dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE); |
bd4c625c LT |
991 | if (IS_ERR(dir)) { |
992 | err = PTR_ERR(dir); | |
993 | if (err == -ENODATA) | |
994 | err = 0; /* Not an error if there aren't any xattrs */ | |
995 | goto out; | |
996 | } | |
997 | ||
bd4c625c LT |
998 | buf.r_buf = buffer; |
999 | buf.r_size = buffer ? size : 0; | |
1000 | buf.r_pos = 0; | |
1001 | buf.r_inode = dentry->d_inode; | |
1002 | ||
1003 | REISERFS_I(dentry->d_inode)->i_flags |= i_has_xattr_dir; | |
1004 | ||
6c17675e | 1005 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
3227e14c | 1006 | err = xattr_readdir(dir->d_inode, reiserfs_listxattr_filler, &buf); |
6c17675e | 1007 | mutex_unlock(&dir->d_inode->i_mutex); |
bd4c625c LT |
1008 | if (err) |
1009 | goto out_dir; | |
1010 | ||
1011 | if (buf.r_pos > buf.r_size && buffer != NULL) | |
1012 | err = -ERANGE; | |
1013 | else | |
1014 | err = buf.r_pos; | |
1015 | ||
1016 | out_dir: | |
3227e14c | 1017 | dput(dir); |
bd4c625c LT |
1018 | |
1019 | out: | |
1020 | reiserfs_read_unlock_xattr_i(dentry->d_inode); | |
1021 | return err; | |
1da177e4 LT |
1022 | } |
1023 | ||
1024 | /* This is the implementation for the xattr plugin infrastructure */ | |
bcf11cbe | 1025 | static LIST_HEAD(xattr_handlers); |
1da177e4 LT |
1026 | static DEFINE_RWLOCK(handler_lock); |
1027 | ||
bd4c625c LT |
1028 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char |
1029 | *prefix) | |
1da177e4 | 1030 | { |
bd4c625c LT |
1031 | struct reiserfs_xattr_handler *xah = NULL; |
1032 | struct list_head *p; | |
1033 | ||
1034 | read_lock(&handler_lock); | |
1035 | list_for_each(p, &xattr_handlers) { | |
1036 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1037 | if (strncmp(xah->prefix, prefix, strlen(xah->prefix)) == 0) | |
1038 | break; | |
1039 | xah = NULL; | |
1040 | } | |
1041 | ||
1042 | read_unlock(&handler_lock); | |
1043 | return xah; | |
1da177e4 LT |
1044 | } |
1045 | ||
bd4c625c | 1046 | static void __unregister_handlers(void) |
1da177e4 | 1047 | { |
bd4c625c LT |
1048 | struct reiserfs_xattr_handler *xah; |
1049 | struct list_head *p, *tmp; | |
1da177e4 | 1050 | |
bd4c625c LT |
1051 | list_for_each_safe(p, tmp, &xattr_handlers) { |
1052 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1053 | if (xah->exit) | |
1054 | xah->exit(); | |
1da177e4 | 1055 | |
bd4c625c LT |
1056 | list_del_init(p); |
1057 | } | |
1058 | INIT_LIST_HEAD(&xattr_handlers); | |
1da177e4 LT |
1059 | } |
1060 | ||
bd4c625c | 1061 | int __init reiserfs_xattr_register_handlers(void) |
1da177e4 | 1062 | { |
bd4c625c LT |
1063 | int err = 0; |
1064 | struct reiserfs_xattr_handler *xah; | |
1065 | struct list_head *p; | |
1da177e4 | 1066 | |
bd4c625c | 1067 | write_lock(&handler_lock); |
1da177e4 | 1068 | |
bd4c625c LT |
1069 | /* If we're already initialized, nothing to do */ |
1070 | if (!list_empty(&xattr_handlers)) { | |
1071 | write_unlock(&handler_lock); | |
1072 | return 0; | |
1073 | } | |
1da177e4 | 1074 | |
bd4c625c LT |
1075 | /* Add the handlers */ |
1076 | list_add_tail(&user_handler.handlers, &xattr_handlers); | |
1077 | list_add_tail(&trusted_handler.handlers, &xattr_handlers); | |
1da177e4 | 1078 | #ifdef CONFIG_REISERFS_FS_SECURITY |
bd4c625c | 1079 | list_add_tail(&security_handler.handlers, &xattr_handlers); |
1da177e4 LT |
1080 | #endif |
1081 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL | |
bd4c625c LT |
1082 | list_add_tail(&posix_acl_access_handler.handlers, &xattr_handlers); |
1083 | list_add_tail(&posix_acl_default_handler.handlers, &xattr_handlers); | |
1da177e4 LT |
1084 | #endif |
1085 | ||
bd4c625c LT |
1086 | /* Run initializers, if available */ |
1087 | list_for_each(p, &xattr_handlers) { | |
1088 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1089 | if (xah->init) { | |
1090 | err = xah->init(); | |
1091 | if (err) { | |
1092 | list_del_init(p); | |
1093 | break; | |
1094 | } | |
1095 | } | |
1096 | } | |
1097 | ||
1098 | /* Clean up other handlers, if any failed */ | |
1099 | if (err) | |
1100 | __unregister_handlers(); | |
1101 | ||
1102 | write_unlock(&handler_lock); | |
1103 | return err; | |
1da177e4 LT |
1104 | } |
1105 | ||
bd4c625c | 1106 | void reiserfs_xattr_unregister_handlers(void) |
1da177e4 | 1107 | { |
bd4c625c LT |
1108 | write_lock(&handler_lock); |
1109 | __unregister_handlers(); | |
1110 | write_unlock(&handler_lock); | |
1da177e4 LT |
1111 | } |
1112 | ||
a72bdb1c JM |
1113 | static int reiserfs_check_acl(struct inode *inode, int mask) |
1114 | { | |
1115 | struct posix_acl *acl; | |
1116 | int error = -EAGAIN; /* do regular unix permission checks by default */ | |
1117 | ||
1118 | reiserfs_read_lock_xattr_i(inode); | |
a72bdb1c JM |
1119 | |
1120 | acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS); | |
1121 | ||
a72bdb1c JM |
1122 | reiserfs_read_unlock_xattr_i(inode); |
1123 | ||
1124 | if (acl) { | |
1125 | if (!IS_ERR(acl)) { | |
1126 | error = posix_acl_permission(inode, acl, mask); | |
1127 | posix_acl_release(acl); | |
1128 | } else if (PTR_ERR(acl) != -ENODATA) | |
1129 | error = PTR_ERR(acl); | |
1130 | } | |
1131 | ||
1132 | return error; | |
1133 | } | |
1134 | ||
1135 | int reiserfs_permission(struct inode *inode, int mask) | |
1136 | { | |
1137 | /* | |
1138 | * We don't do permission checks on the internal objects. | |
1139 | * Permissions are determined by the "owning" object. | |
1140 | */ | |
1141 | if (IS_PRIVATE(inode)) | |
1142 | return 0; | |
1143 | /* | |
1144 | * Stat data v1 doesn't support ACLs. | |
1145 | */ | |
1146 | if (get_inode_sd_version(inode) == STAT_DATA_V1) | |
1147 | return generic_permission(inode, mask, NULL); | |
1148 | else | |
1149 | return generic_permission(inode, mask, reiserfs_check_acl); | |
1150 | } | |
1151 | ||
1152 | static int create_privroot(struct dentry *dentry) | |
1153 | { | |
1154 | int err; | |
1155 | struct inode *inode = dentry->d_parent->d_inode; | |
1156 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_XATTR); | |
6c17675e | 1157 | err = xattr_mkdir(inode, dentry, 0700); |
a72bdb1c JM |
1158 | mutex_unlock(&inode->i_mutex); |
1159 | if (err) { | |
1160 | dput(dentry); | |
1161 | dentry = NULL; | |
1162 | } | |
1163 | ||
1164 | if (dentry && dentry->d_inode) | |
1165 | reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr " | |
1166 | "storage.\n", PRIVROOT_NAME); | |
1167 | ||
1168 | return err; | |
1169 | } | |
1170 | ||
1171 | static int xattr_mount_check(struct super_block *s) | |
1172 | { | |
1173 | /* We need generation numbers to ensure that the oid mapping is correct | |
1174 | * v3.5 filesystems don't have them. */ | |
1175 | if (!old_format_only(s)) { | |
1176 | set_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1177 | } else if (reiserfs_xattrs_optional(s)) { | |
1178 | /* Old format filesystem, but optional xattrs have been enabled | |
1179 | * at mount time. Error out. */ | |
1180 | reiserfs_warning(s, "jdm-20005", | |
1181 | "xattrs/ACLs not supported on pre v3.6 " | |
1182 | "format filesystem. Failing mount."); | |
1183 | return -EOPNOTSUPP; | |
1184 | } else { | |
1185 | /* Old format filesystem, but no optional xattrs have | |
1186 | * been enabled. This means we silently disable xattrs | |
1187 | * on the filesystem. */ | |
1188 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1189 | } | |
1190 | ||
1191 | return 0; | |
1192 | } | |
1193 | ||
1194 | #else | |
1195 | int __init reiserfs_xattr_register_handlers(void) { return 0; } | |
1196 | void reiserfs_xattr_unregister_handlers(void) {} | |
1197 | #endif | |
1198 | ||
1da177e4 LT |
1199 | /* This will catch lookups from the fs root to .reiserfs_priv */ |
1200 | static int | |
bd4c625c | 1201 | xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name) |
1da177e4 | 1202 | { |
bd4c625c LT |
1203 | struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root; |
1204 | if (name->len == priv_root->d_name.len && | |
1205 | name->hash == priv_root->d_name.hash && | |
1206 | !memcmp(name->name, priv_root->d_name.name, name->len)) { | |
1207 | return -ENOENT; | |
1208 | } else if (q1->len == name->len && | |
1209 | !memcmp(q1->name, name->name, name->len)) | |
1210 | return 0; | |
1211 | return 1; | |
1da177e4 LT |
1212 | } |
1213 | ||
1214 | static struct dentry_operations xattr_lookup_poison_ops = { | |
bd4c625c | 1215 | .d_compare = xattr_lookup_poison, |
1da177e4 LT |
1216 | }; |
1217 | ||
1da177e4 LT |
1218 | /* We need to take a copy of the mount flags since things like |
1219 | * MS_RDONLY don't get set until *after* we're called. | |
1220 | * mount_flags != mount_options */ | |
bd4c625c | 1221 | int reiserfs_xattr_init(struct super_block *s, int mount_flags) |
1da177e4 | 1222 | { |
bd4c625c LT |
1223 | int err = 0; |
1224 | ||
a72bdb1c JM |
1225 | #ifdef CONFIG_REISERFS_FS_XATTR |
1226 | err = xattr_mount_check(s); | |
1227 | if (err) | |
bd4c625c | 1228 | goto error; |
a72bdb1c | 1229 | #endif |
bd4c625c LT |
1230 | |
1231 | /* If we don't have the privroot located yet - go find it */ | |
a72bdb1c | 1232 | if (!REISERFS_SB(s)->priv_root) { |
bd4c625c LT |
1233 | struct dentry *dentry; |
1234 | dentry = lookup_one_len(PRIVROOT_NAME, s->s_root, | |
1235 | strlen(PRIVROOT_NAME)); | |
1236 | if (!IS_ERR(dentry)) { | |
a72bdb1c JM |
1237 | #ifdef CONFIG_REISERFS_FS_XATTR |
1238 | if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) | |
1239 | err = create_privroot(dentry); | |
1240 | #endif | |
1241 | if (!dentry->d_inode) { | |
bd4c625c LT |
1242 | dput(dentry); |
1243 | dentry = NULL; | |
1244 | } | |
1245 | } else | |
1246 | err = PTR_ERR(dentry); | |
1247 | ||
1248 | if (!err && dentry) { | |
1249 | s->s_root->d_op = &xattr_lookup_poison_ops; | |
6dfede69 | 1250 | dentry->d_inode->i_flags |= S_PRIVATE; |
bd4c625c | 1251 | REISERFS_SB(s)->priv_root = dentry; |
a72bdb1c JM |
1252 | #ifdef CONFIG_REISERFS_FS_XATTR |
1253 | /* xattrs are unavailable */ | |
1254 | } else if (!(mount_flags & MS_RDONLY)) { | |
1255 | /* If we're read-only it just means that the dir | |
1256 | * hasn't been created. Not an error -- just no | |
1257 | * xattrs on the fs. We'll check again if we | |
1258 | * go read-write */ | |
45b03d5e JM |
1259 | reiserfs_warning(s, "jdm-20006", |
1260 | "xattrs/ACLs enabled and couldn't " | |
1261 | "find/create .reiserfs_priv. " | |
1262 | "Failing mount."); | |
bd4c625c | 1263 | err = -EOPNOTSUPP; |
a72bdb1c | 1264 | #endif |
bd4c625c LT |
1265 | } |
1266 | } | |
1267 | ||
a72bdb1c JM |
1268 | #ifdef CONFIG_REISERFS_FS_XATTR |
1269 | error: | |
bd4c625c LT |
1270 | if (err) { |
1271 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1272 | clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt)); | |
1273 | clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt)); | |
1274 | } | |
a72bdb1c | 1275 | #endif |
bd4c625c LT |
1276 | |
1277 | /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */ | |
1278 | s->s_flags = s->s_flags & ~MS_POSIXACL; | |
a72bdb1c | 1279 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL |
bd4c625c LT |
1280 | if (reiserfs_posixacl(s)) |
1281 | s->s_flags |= MS_POSIXACL; | |
a72bdb1c | 1282 | #endif |
bd4c625c LT |
1283 | |
1284 | return err; | |
1da177e4 | 1285 | } |