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