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> | |
1da177e4 LT |
47 | |
48 | #define FL_READONLY 128 | |
49 | #define FL_DIR_SEM_HELD 256 | |
50 | #define PRIVROOT_NAME ".reiserfs_priv" | |
51 | #define XAROOT_NAME "xattrs" | |
52 | ||
bd4c625c LT |
53 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char |
54 | *prefix); | |
1da177e4 | 55 | |
9b7f3755 JM |
56 | /* Returns the dentry referring to the root of the extended attribute |
57 | * directory tree. If it has already been retrieved, it is used. If it | |
58 | * hasn't been created and the flags indicate creation is allowed, we | |
59 | * attempt to create it. On error, we return a pointer-encoded error. | |
60 | */ | |
61 | static struct dentry *get_xa_root(struct super_block *sb, int flags) | |
1da177e4 | 62 | { |
bd4c625c LT |
63 | struct dentry *privroot = dget(REISERFS_SB(sb)->priv_root); |
64 | struct dentry *xaroot; | |
65 | ||
66 | /* This needs to be created at mount-time */ | |
67 | if (!privroot) | |
9b7f3755 | 68 | return ERR_PTR(-ENODATA); |
bd4c625c | 69 | |
1173a729 | 70 | mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR); |
9b7f3755 JM |
71 | if (REISERFS_SB(sb)->xattr_root) { |
72 | xaroot = dget(REISERFS_SB(sb)->xattr_root); | |
bd4c625c | 73 | goto out; |
bd4c625c LT |
74 | } |
75 | ||
bd4c625c LT |
76 | xaroot = lookup_one_len(XAROOT_NAME, privroot, strlen(XAROOT_NAME)); |
77 | if (IS_ERR(xaroot)) { | |
78 | goto out; | |
79 | } else if (!xaroot->d_inode) { | |
9b7f3755 JM |
80 | int err = -ENODATA; |
81 | if (flags == 0 || flags & XATTR_CREATE) | |
82 | err = privroot->d_inode->i_op->mkdir(privroot->d_inode, | |
83 | xaroot, 0700); | |
84 | if (err) { | |
85 | dput(xaroot); | |
86 | xaroot = ERR_PTR(err); | |
87 | goto out; | |
88 | } | |
bd4c625c | 89 | } |
9b7f3755 | 90 | REISERFS_SB(sb)->xattr_root = dget(xaroot); |
bd4c625c LT |
91 | |
92 | out: | |
9b7f3755 | 93 | mutex_unlock(&privroot->d_inode->i_mutex); |
bd4c625c LT |
94 | dput(privroot); |
95 | return xaroot; | |
1da177e4 LT |
96 | } |
97 | ||
1da177e4 LT |
98 | /* Opens the directory corresponding to the inode's extended attribute store. |
99 | * If flags allow, the tree to the directory may be created. If creation is | |
100 | * prohibited, -ENODATA is returned. */ | |
bd4c625c | 101 | static struct dentry *open_xa_dir(const struct inode *inode, int flags) |
1da177e4 | 102 | { |
bd4c625c LT |
103 | struct dentry *xaroot, *xadir; |
104 | char namebuf[17]; | |
105 | ||
9b7f3755 JM |
106 | xaroot = get_xa_root(inode->i_sb, flags); |
107 | if (IS_ERR(xaroot)) | |
bd4c625c | 108 | return xaroot; |
bd4c625c LT |
109 | |
110 | /* ok, we have xaroot open */ | |
bd4c625c LT |
111 | snprintf(namebuf, sizeof(namebuf), "%X.%X", |
112 | le32_to_cpu(INODE_PKEY(inode)->k_objectid), | |
113 | inode->i_generation); | |
114 | xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf)); | |
115 | if (IS_ERR(xadir)) { | |
116 | dput(xaroot); | |
117 | return xadir; | |
118 | } | |
119 | ||
120 | if (!xadir->d_inode) { | |
121 | int err; | |
122 | if (flags == 0 || flags & XATTR_CREATE) { | |
123 | /* Although there is nothing else trying to create this directory, | |
124 | * another directory with the same hash may be created, so we need | |
125 | * to protect against that */ | |
126 | err = | |
127 | xaroot->d_inode->i_op->mkdir(xaroot->d_inode, xadir, | |
128 | 0700); | |
129 | if (err) { | |
130 | dput(xaroot); | |
131 | dput(xadir); | |
132 | return ERR_PTR(err); | |
133 | } | |
134 | } | |
135 | if (!xadir->d_inode) { | |
136 | dput(xaroot); | |
137 | dput(xadir); | |
138 | return ERR_PTR(-ENODATA); | |
139 | } | |
140 | } | |
141 | ||
142 | dput(xaroot); | |
143 | return xadir; | |
1da177e4 LT |
144 | } |
145 | ||
146 | /* Returns a dentry corresponding to a specific extended attribute file | |
147 | * for the inode. If flags allow, the file is created. Otherwise, a | |
148 | * valid or negative dentry, or an error is returned. */ | |
bd4c625c LT |
149 | static struct dentry *get_xa_file_dentry(const struct inode *inode, |
150 | const char *name, int flags) | |
1da177e4 | 151 | { |
bd4c625c LT |
152 | struct dentry *xadir, *xafile; |
153 | int err = 0; | |
154 | ||
155 | xadir = open_xa_dir(inode, flags); | |
156 | if (IS_ERR(xadir)) { | |
e231c2ee | 157 | return ERR_CAST(xadir); |
67b172c0 | 158 | } else if (!xadir->d_inode) { |
bd4c625c LT |
159 | dput(xadir); |
160 | return ERR_PTR(-ENODATA); | |
161 | } | |
162 | ||
163 | xafile = lookup_one_len(name, xadir, strlen(name)); | |
164 | if (IS_ERR(xafile)) { | |
165 | dput(xadir); | |
e231c2ee | 166 | return ERR_CAST(xafile); |
bd4c625c LT |
167 | } |
168 | ||
169 | if (xafile->d_inode) { /* file exists */ | |
170 | if (flags & XATTR_CREATE) { | |
171 | err = -EEXIST; | |
172 | dput(xafile); | |
173 | goto out; | |
174 | } | |
175 | } else if (flags & XATTR_REPLACE || flags & FL_READONLY) { | |
176 | goto out; | |
177 | } else { | |
1b1dcc1b | 178 | /* inode->i_mutex is down, so nothing else can try to create |
bd4c625c LT |
179 | * the same xattr */ |
180 | err = xadir->d_inode->i_op->create(xadir->d_inode, xafile, | |
181 | 0700 | S_IFREG, NULL); | |
182 | ||
183 | if (err) { | |
184 | dput(xafile); | |
185 | goto out; | |
186 | } | |
187 | } | |
1da177e4 | 188 | |
bd4c625c LT |
189 | out: |
190 | dput(xadir); | |
191 | if (err) | |
192 | xafile = ERR_PTR(err); | |
bd4c625c LT |
193 | else if (!xafile->d_inode) { |
194 | dput(xafile); | |
3227e14c | 195 | xafile = ERR_PTR(-ENODATA); |
bd4c625c | 196 | } |
3227e14c | 197 | return xafile; |
1da177e4 LT |
198 | } |
199 | ||
1da177e4 LT |
200 | /* |
201 | * this is very similar to fs/reiserfs/dir.c:reiserfs_readdir, but | |
202 | * we need to drop the path before calling the filldir struct. That | |
203 | * would be a big performance hit to the non-xattr case, so I've copied | |
204 | * the whole thing for now. --clm | |
205 | * | |
206 | * the big difference is that I go backwards through the directory, | |
207 | * and don't mess with f->f_pos, but the idea is the same. Do some | |
208 | * action on each and every entry in the directory. | |
209 | * | |
1b1dcc1b | 210 | * we're called with i_mutex held, so there are no worries about the directory |
1da177e4 LT |
211 | * changing underneath us. |
212 | */ | |
3227e14c | 213 | static int __xattr_readdir(struct inode *inode, void *dirent, filldir_t filldir) |
1da177e4 | 214 | { |
bd4c625c LT |
215 | struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */ |
216 | INITIALIZE_PATH(path_to_entry); | |
217 | struct buffer_head *bh; | |
218 | int entry_num; | |
219 | struct item_head *ih, tmp_ih; | |
220 | int search_res; | |
221 | char *local_buf; | |
222 | loff_t next_pos; | |
223 | char small_buf[32]; /* avoid kmalloc if we can */ | |
224 | struct reiserfs_de_head *deh; | |
225 | int d_reclen; | |
226 | char *d_name; | |
227 | off_t d_off; | |
228 | ino_t d_ino; | |
229 | struct reiserfs_dir_entry de; | |
230 | ||
231 | /* form key for search the next directory entry using f_pos field of | |
232 | file structure */ | |
233 | next_pos = max_reiserfs_offset(inode); | |
234 | ||
235 | while (1) { | |
236 | research: | |
237 | if (next_pos <= DOT_DOT_OFFSET) | |
238 | break; | |
239 | make_cpu_key(&pos_key, inode, next_pos, TYPE_DIRENTRY, 3); | |
240 | ||
241 | search_res = | |
242 | search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry, | |
243 | &de); | |
244 | if (search_res == IO_ERROR) { | |
245 | // FIXME: we could just skip part of directory which could | |
246 | // not be read | |
247 | pathrelse(&path_to_entry); | |
248 | return -EIO; | |
249 | } | |
1da177e4 | 250 | |
bd4c625c LT |
251 | if (search_res == NAME_NOT_FOUND) |
252 | de.de_entry_num--; | |
1da177e4 | 253 | |
bd4c625c LT |
254 | set_de_name_and_namelen(&de); |
255 | entry_num = de.de_entry_num; | |
256 | deh = &(de.de_deh[entry_num]); | |
1da177e4 | 257 | |
bd4c625c LT |
258 | bh = de.de_bh; |
259 | ih = de.de_ih; | |
1da177e4 | 260 | |
bd4c625c LT |
261 | if (!is_direntry_le_ih(ih)) { |
262 | reiserfs_warning(inode->i_sb, "not direntry %h", ih); | |
263 | break; | |
264 | } | |
265 | copy_item_head(&tmp_ih, ih); | |
1da177e4 | 266 | |
bd4c625c LT |
267 | /* we must have found item, that is item of this directory, */ |
268 | RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key), | |
269 | "vs-9000: found item %h does not match to dir we readdir %K", | |
270 | ih, &pos_key); | |
1da177e4 | 271 | |
bd4c625c LT |
272 | if (deh_offset(deh) <= DOT_DOT_OFFSET) { |
273 | break; | |
274 | } | |
1da177e4 | 275 | |
bd4c625c LT |
276 | /* look for the previous entry in the directory */ |
277 | next_pos = deh_offset(deh) - 1; | |
1da177e4 | 278 | |
bd4c625c LT |
279 | if (!de_visible(deh)) |
280 | /* it is hidden entry */ | |
281 | continue; | |
1da177e4 | 282 | |
bd4c625c LT |
283 | d_reclen = entry_length(bh, ih, entry_num); |
284 | d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh); | |
285 | d_off = deh_offset(deh); | |
286 | d_ino = deh_objectid(deh); | |
1da177e4 | 287 | |
bd4c625c LT |
288 | if (!d_name[d_reclen - 1]) |
289 | d_reclen = strlen(d_name); | |
1da177e4 | 290 | |
bd4c625c LT |
291 | if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)) { |
292 | /* too big to send back to VFS */ | |
293 | continue; | |
294 | } | |
1da177e4 | 295 | |
bd4c625c LT |
296 | /* Ignore the .reiserfs_priv entry */ |
297 | if (reiserfs_xattrs(inode->i_sb) && | |
298 | !old_format_only(inode->i_sb) && | |
299 | deh_objectid(deh) == | |
300 | le32_to_cpu(INODE_PKEY | |
301 | (REISERFS_SB(inode->i_sb)->priv_root->d_inode)-> | |
302 | k_objectid)) | |
303 | continue; | |
304 | ||
305 | if (d_reclen <= 32) { | |
306 | local_buf = small_buf; | |
307 | } else { | |
d739b42b | 308 | local_buf = kmalloc(d_reclen, GFP_NOFS); |
bd4c625c LT |
309 | if (!local_buf) { |
310 | pathrelse(&path_to_entry); | |
311 | return -ENOMEM; | |
312 | } | |
313 | if (item_moved(&tmp_ih, &path_to_entry)) { | |
d739b42b | 314 | kfree(local_buf); |
bd4c625c LT |
315 | |
316 | /* sigh, must retry. Do this same offset again */ | |
317 | next_pos = d_off; | |
318 | goto research; | |
319 | } | |
320 | } | |
1da177e4 | 321 | |
bd4c625c LT |
322 | // Note, that we copy name to user space via temporary |
323 | // buffer (local_buf) because filldir will block if | |
324 | // user space buffer is swapped out. At that time | |
325 | // entry can move to somewhere else | |
326 | memcpy(local_buf, d_name, d_reclen); | |
1da177e4 | 327 | |
bd4c625c LT |
328 | /* the filldir function might need to start transactions, |
329 | * or do who knows what. Release the path now that we've | |
330 | * copied all the important stuff out of the deh | |
331 | */ | |
332 | pathrelse(&path_to_entry); | |
333 | ||
334 | if (filldir(dirent, local_buf, d_reclen, d_off, d_ino, | |
335 | DT_UNKNOWN) < 0) { | |
336 | if (local_buf != small_buf) { | |
d739b42b | 337 | kfree(local_buf); |
bd4c625c LT |
338 | } |
339 | goto end; | |
340 | } | |
341 | if (local_buf != small_buf) { | |
d739b42b | 342 | kfree(local_buf); |
bd4c625c LT |
343 | } |
344 | } /* while */ | |
1da177e4 | 345 | |
bd4c625c LT |
346 | end: |
347 | pathrelse(&path_to_entry); | |
348 | return 0; | |
1da177e4 LT |
349 | } |
350 | ||
351 | /* | |
352 | * this could be done with dedicated readdir ops for the xattr files, | |
353 | * but I want to get something working asap | |
354 | * this is stolen from vfs_readdir | |
355 | * | |
356 | */ | |
357 | static | |
3227e14c | 358 | int xattr_readdir(struct inode *inode, filldir_t filler, void *buf) |
1da177e4 | 359 | { |
3227e14c | 360 | int res = -ENOENT; |
4df46240 | 361 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_XATTR); |
bd4c625c LT |
362 | if (!IS_DEADDIR(inode)) { |
363 | lock_kernel(); | |
3227e14c | 364 | res = __xattr_readdir(inode, buf, filler); |
bd4c625c LT |
365 | unlock_kernel(); |
366 | } | |
1b1dcc1b | 367 | mutex_unlock(&inode->i_mutex); |
bd4c625c | 368 | return res; |
1da177e4 LT |
369 | } |
370 | ||
1da177e4 | 371 | /* Internal operations on file data */ |
bd4c625c | 372 | static inline void reiserfs_put_page(struct page *page) |
1da177e4 | 373 | { |
bd4c625c LT |
374 | kunmap(page); |
375 | page_cache_release(page); | |
1da177e4 LT |
376 | } |
377 | ||
bd4c625c | 378 | static struct page *reiserfs_get_page(struct inode *dir, unsigned long n) |
1da177e4 | 379 | { |
bd4c625c LT |
380 | struct address_space *mapping = dir->i_mapping; |
381 | struct page *page; | |
382 | /* We can deadlock if we try to free dentries, | |
383 | and an unlink/rmdir has just occured - GFP_NOFS avoids this */ | |
c4cdd038 | 384 | mapping_set_gfp_mask(mapping, GFP_NOFS); |
090d2b18 | 385 | page = read_mapping_page(mapping, n, NULL); |
bd4c625c | 386 | if (!IS_ERR(page)) { |
bd4c625c | 387 | kmap(page); |
bd4c625c LT |
388 | if (PageError(page)) |
389 | goto fail; | |
390 | } | |
391 | return page; | |
392 | ||
393 | fail: | |
394 | reiserfs_put_page(page); | |
395 | return ERR_PTR(-EIO); | |
1da177e4 LT |
396 | } |
397 | ||
bd4c625c | 398 | static inline __u32 xattr_hash(const char *msg, int len) |
1da177e4 | 399 | { |
bd4c625c | 400 | return csum_partial(msg, len, 0); |
1da177e4 LT |
401 | } |
402 | ||
ba9d8cec VS |
403 | int reiserfs_commit_write(struct file *f, struct page *page, |
404 | unsigned from, unsigned to); | |
405 | int reiserfs_prepare_write(struct file *f, struct page *page, | |
406 | unsigned from, unsigned to); | |
407 | ||
408 | ||
1da177e4 LT |
409 | /* Generic extended attribute operations that can be used by xa plugins */ |
410 | ||
411 | /* | |
1b1dcc1b | 412 | * inode->i_mutex: down |
1da177e4 LT |
413 | */ |
414 | int | |
bd4c625c LT |
415 | reiserfs_xattr_set(struct inode *inode, const char *name, const void *buffer, |
416 | size_t buffer_size, int flags) | |
1da177e4 | 417 | { |
bd4c625c | 418 | int err = 0; |
3227e14c | 419 | struct dentry *dentry; |
bd4c625c LT |
420 | struct page *page; |
421 | char *data; | |
422 | struct address_space *mapping; | |
423 | size_t file_pos = 0; | |
424 | size_t buffer_pos = 0; | |
425 | struct inode *xinode; | |
426 | struct iattr newattrs; | |
427 | __u32 xahash = 0; | |
428 | ||
bd4c625c LT |
429 | if (get_inode_sd_version(inode) == STAT_DATA_V1) |
430 | return -EOPNOTSUPP; | |
431 | ||
432 | /* Empty xattrs are ok, they're just empty files, no hash */ | |
433 | if (buffer && buffer_size) | |
434 | xahash = xattr_hash(buffer, buffer_size); | |
435 | ||
436 | open_file: | |
3227e14c JM |
437 | dentry = get_xa_file_dentry(inode, name, flags); |
438 | if (IS_ERR(dentry)) { | |
439 | err = PTR_ERR(dentry); | |
bd4c625c LT |
440 | goto out; |
441 | } | |
442 | ||
3227e14c | 443 | xinode = dentry->d_inode; |
bd4c625c LT |
444 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; |
445 | ||
446 | /* we need to copy it off.. */ | |
447 | if (xinode->i_nlink > 1) { | |
3227e14c | 448 | dput(dentry); |
bd4c625c LT |
449 | err = reiserfs_xattr_del(inode, name); |
450 | if (err < 0) | |
451 | goto out; | |
452 | /* We just killed the old one, we're not replacing anymore */ | |
453 | if (flags & XATTR_REPLACE) | |
454 | flags &= ~XATTR_REPLACE; | |
455 | goto open_file; | |
456 | } | |
457 | ||
458 | /* Resize it so we're ok to write there */ | |
459 | newattrs.ia_size = buffer_size; | |
460 | newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME; | |
75983928 | 461 | mutex_lock_nested(&xinode->i_mutex, I_MUTEX_XATTR); |
3227e14c | 462 | err = notify_change(dentry, &newattrs); |
bd4c625c LT |
463 | if (err) |
464 | goto out_filp; | |
465 | ||
466 | mapping = xinode->i_mapping; | |
467 | while (buffer_pos < buffer_size || buffer_pos == 0) { | |
468 | size_t chunk; | |
469 | size_t skip = 0; | |
470 | size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1)); | |
471 | if (buffer_size - buffer_pos > PAGE_CACHE_SIZE) | |
472 | chunk = PAGE_CACHE_SIZE; | |
473 | else | |
474 | chunk = buffer_size - buffer_pos; | |
475 | ||
476 | page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT); | |
477 | if (IS_ERR(page)) { | |
478 | err = PTR_ERR(page); | |
479 | goto out_filp; | |
480 | } | |
481 | ||
482 | lock_page(page); | |
483 | data = page_address(page); | |
484 | ||
485 | if (file_pos == 0) { | |
486 | struct reiserfs_xattr_header *rxh; | |
487 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
488 | if (chunk + skip > PAGE_CACHE_SIZE) | |
489 | chunk = PAGE_CACHE_SIZE - skip; | |
490 | rxh = (struct reiserfs_xattr_header *)data; | |
491 | rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC); | |
492 | rxh->h_hash = cpu_to_le32(xahash); | |
493 | } | |
494 | ||
3227e14c | 495 | err = reiserfs_prepare_write(NULL, page, page_offset, |
ba9d8cec | 496 | page_offset + chunk + skip); |
bd4c625c LT |
497 | if (!err) { |
498 | if (buffer) | |
499 | memcpy(data + skip, buffer + buffer_pos, chunk); | |
3227e14c JM |
500 | err = reiserfs_commit_write(NULL, page, page_offset, |
501 | page_offset + chunk + | |
502 | skip); | |
bd4c625c LT |
503 | } |
504 | unlock_page(page); | |
505 | reiserfs_put_page(page); | |
506 | buffer_pos += chunk; | |
507 | file_pos += chunk; | |
508 | skip = 0; | |
509 | if (err || buffer_size == 0 || !buffer) | |
510 | break; | |
511 | } | |
512 | ||
513 | /* We can't mark the inode dirty if it's not hashed. This is the case | |
514 | * when we're inheriting the default ACL. If we dirty it, the inode | |
515 | * gets marked dirty, but won't (ever) make it onto the dirty list until | |
516 | * it's synced explicitly to clear I_DIRTY. This is bad. */ | |
517 | if (!hlist_unhashed(&inode->i_hash)) { | |
518 | inode->i_ctime = CURRENT_TIME_SEC; | |
519 | mark_inode_dirty(inode); | |
1da177e4 | 520 | } |
bd4c625c LT |
521 | |
522 | out_filp: | |
1b1dcc1b | 523 | mutex_unlock(&xinode->i_mutex); |
3227e14c | 524 | dput(dentry); |
bd4c625c LT |
525 | |
526 | out: | |
527 | return err; | |
1da177e4 LT |
528 | } |
529 | ||
530 | /* | |
1b1dcc1b | 531 | * inode->i_mutex: down |
1da177e4 LT |
532 | */ |
533 | int | |
bd4c625c LT |
534 | reiserfs_xattr_get(const struct inode *inode, const char *name, void *buffer, |
535 | size_t buffer_size) | |
1da177e4 | 536 | { |
bd4c625c | 537 | ssize_t err = 0; |
3227e14c | 538 | struct dentry *dentry; |
bd4c625c LT |
539 | size_t isize; |
540 | size_t file_pos = 0; | |
541 | size_t buffer_pos = 0; | |
542 | struct page *page; | |
543 | struct inode *xinode; | |
544 | __u32 hash = 0; | |
545 | ||
546 | if (name == NULL) | |
547 | return -EINVAL; | |
548 | ||
549 | /* We can't have xattrs attached to v1 items since they don't have | |
550 | * generation numbers */ | |
551 | if (get_inode_sd_version(inode) == STAT_DATA_V1) | |
552 | return -EOPNOTSUPP; | |
553 | ||
3227e14c JM |
554 | dentry = get_xa_file_dentry(inode, name, FL_READONLY); |
555 | if (IS_ERR(dentry)) { | |
556 | err = PTR_ERR(dentry); | |
bd4c625c LT |
557 | goto out; |
558 | } | |
559 | ||
3227e14c | 560 | xinode = dentry->d_inode; |
bd4c625c LT |
561 | isize = xinode->i_size; |
562 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; | |
563 | ||
564 | /* Just return the size needed */ | |
565 | if (buffer == NULL) { | |
566 | err = isize - sizeof(struct reiserfs_xattr_header); | |
567 | goto out_dput; | |
568 | } | |
569 | ||
570 | if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) { | |
571 | err = -ERANGE; | |
572 | goto out_dput; | |
573 | } | |
574 | ||
575 | while (file_pos < isize) { | |
576 | size_t chunk; | |
577 | char *data; | |
578 | size_t skip = 0; | |
579 | if (isize - file_pos > PAGE_CACHE_SIZE) | |
580 | chunk = PAGE_CACHE_SIZE; | |
581 | else | |
582 | chunk = isize - file_pos; | |
583 | ||
584 | page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT); | |
585 | if (IS_ERR(page)) { | |
586 | err = PTR_ERR(page); | |
587 | goto out_dput; | |
588 | } | |
589 | ||
590 | lock_page(page); | |
591 | data = page_address(page); | |
592 | if (file_pos == 0) { | |
593 | struct reiserfs_xattr_header *rxh = | |
594 | (struct reiserfs_xattr_header *)data; | |
595 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
596 | chunk -= skip; | |
597 | /* Magic doesn't match up.. */ | |
598 | if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) { | |
599 | unlock_page(page); | |
600 | reiserfs_put_page(page); | |
601 | reiserfs_warning(inode->i_sb, | |
602 | "Invalid magic for xattr (%s) " | |
603 | "associated with %k", name, | |
604 | INODE_PKEY(inode)); | |
605 | err = -EIO; | |
606 | goto out_dput; | |
607 | } | |
608 | hash = le32_to_cpu(rxh->h_hash); | |
609 | } | |
610 | memcpy(buffer + buffer_pos, data + skip, chunk); | |
611 | unlock_page(page); | |
612 | reiserfs_put_page(page); | |
613 | file_pos += chunk; | |
614 | buffer_pos += chunk; | |
615 | skip = 0; | |
616 | } | |
617 | err = isize - sizeof(struct reiserfs_xattr_header); | |
618 | ||
619 | if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) != | |
620 | hash) { | |
621 | reiserfs_warning(inode->i_sb, | |
622 | "Invalid hash for xattr (%s) associated " | |
623 | "with %k", name, INODE_PKEY(inode)); | |
624 | err = -EIO; | |
625 | } | |
626 | ||
627 | out_dput: | |
3227e14c | 628 | dput(dentry); |
bd4c625c LT |
629 | |
630 | out: | |
631 | return err; | |
1da177e4 LT |
632 | } |
633 | ||
634 | static int | |
bd4c625c | 635 | __reiserfs_xattr_del(struct dentry *xadir, const char *name, int namelen) |
1da177e4 | 636 | { |
bd4c625c LT |
637 | struct dentry *dentry; |
638 | struct inode *dir = xadir->d_inode; | |
639 | int err = 0; | |
640 | ||
641 | dentry = lookup_one_len(name, xadir, namelen); | |
642 | if (IS_ERR(dentry)) { | |
643 | err = PTR_ERR(dentry); | |
644 | goto out; | |
645 | } else if (!dentry->d_inode) { | |
646 | err = -ENODATA; | |
647 | goto out_file; | |
648 | } | |
649 | ||
650 | /* Skip directories.. */ | |
651 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
652 | goto out_file; | |
653 | ||
654 | if (!is_reiserfs_priv_object(dentry->d_inode)) { | |
655 | reiserfs_warning(dir->i_sb, "OID %08x [%.*s/%.*s] doesn't have " | |
656 | "priv flag set [parent is %sset].", | |
657 | le32_to_cpu(INODE_PKEY(dentry->d_inode)-> | |
658 | k_objectid), xadir->d_name.len, | |
659 | xadir->d_name.name, namelen, name, | |
660 | is_reiserfs_priv_object(xadir-> | |
661 | d_inode) ? "" : | |
662 | "not "); | |
663 | dput(dentry); | |
664 | return -EIO; | |
665 | } | |
1da177e4 | 666 | |
bd4c625c LT |
667 | err = dir->i_op->unlink(dir, dentry); |
668 | if (!err) | |
669 | d_delete(dentry); | |
1da177e4 | 670 | |
bd4c625c LT |
671 | out_file: |
672 | dput(dentry); | |
673 | ||
674 | out: | |
675 | return err; | |
676 | } | |
677 | ||
678 | int reiserfs_xattr_del(struct inode *inode, const char *name) | |
1da177e4 | 679 | { |
bd4c625c LT |
680 | struct dentry *dir; |
681 | int err; | |
1da177e4 | 682 | |
bd4c625c LT |
683 | dir = open_xa_dir(inode, FL_READONLY); |
684 | if (IS_ERR(dir)) { | |
685 | err = PTR_ERR(dir); | |
686 | goto out; | |
687 | } | |
1da177e4 | 688 | |
bd4c625c LT |
689 | err = __reiserfs_xattr_del(dir, name, strlen(name)); |
690 | dput(dir); | |
1da177e4 | 691 | |
bd4c625c LT |
692 | if (!err) { |
693 | inode->i_ctime = CURRENT_TIME_SEC; | |
694 | mark_inode_dirty(inode); | |
695 | } | |
1da177e4 | 696 | |
bd4c625c LT |
697 | out: |
698 | return err; | |
1da177e4 LT |
699 | } |
700 | ||
701 | /* The following are side effects of other operations that aren't explicitly | |
702 | * modifying extended attributes. This includes operations such as permissions | |
703 | * or ownership changes, object deletions, etc. */ | |
704 | ||
705 | static int | |
bd4c625c | 706 | reiserfs_delete_xattrs_filler(void *buf, const char *name, int namelen, |
afefdbb2 | 707 | loff_t offset, u64 ino, unsigned int d_type) |
1da177e4 | 708 | { |
bd4c625c | 709 | struct dentry *xadir = (struct dentry *)buf; |
1da177e4 | 710 | |
bd4c625c | 711 | return __reiserfs_xattr_del(xadir, name, namelen); |
1da177e4 LT |
712 | |
713 | } | |
714 | ||
1b1dcc1b | 715 | /* This is called w/ inode->i_mutex downed */ |
bd4c625c | 716 | int reiserfs_delete_xattrs(struct inode *inode) |
1da177e4 | 717 | { |
bd4c625c LT |
718 | struct dentry *dir, *root; |
719 | int err = 0; | |
720 | ||
721 | /* Skip out, an xattr has no xattrs associated with it */ | |
722 | if (is_reiserfs_priv_object(inode) || | |
723 | get_inode_sd_version(inode) == STAT_DATA_V1 || | |
724 | !reiserfs_xattrs(inode->i_sb)) { | |
725 | return 0; | |
726 | } | |
727 | reiserfs_read_lock_xattrs(inode->i_sb); | |
728 | dir = open_xa_dir(inode, FL_READONLY); | |
729 | reiserfs_read_unlock_xattrs(inode->i_sb); | |
730 | if (IS_ERR(dir)) { | |
731 | err = PTR_ERR(dir); | |
732 | goto out; | |
733 | } else if (!dir->d_inode) { | |
734 | dput(dir); | |
735 | return 0; | |
736 | } | |
737 | ||
bd4c625c | 738 | lock_kernel(); |
3227e14c | 739 | err = xattr_readdir(dir->d_inode, reiserfs_delete_xattrs_filler, dir); |
bd4c625c LT |
740 | if (err) { |
741 | unlock_kernel(); | |
742 | goto out_dir; | |
743 | } | |
744 | ||
745 | /* Leftovers besides . and .. -- that's not good. */ | |
746 | if (dir->d_inode->i_nlink <= 2) { | |
9b7f3755 | 747 | root = get_xa_root(inode->i_sb, XATTR_REPLACE); |
bd4c625c LT |
748 | reiserfs_write_lock_xattrs(inode->i_sb); |
749 | err = vfs_rmdir(root->d_inode, dir); | |
750 | reiserfs_write_unlock_xattrs(inode->i_sb); | |
751 | dput(root); | |
752 | } else { | |
753 | reiserfs_warning(inode->i_sb, | |
754 | "Couldn't remove all entries in directory"); | |
755 | } | |
756 | unlock_kernel(); | |
757 | ||
758 | out_dir: | |
3227e14c | 759 | dput(dir); |
bd4c625c LT |
760 | |
761 | out: | |
762 | if (!err) | |
763 | REISERFS_I(inode)->i_flags = | |
764 | REISERFS_I(inode)->i_flags & ~i_has_xattr_dir; | |
765 | return err; | |
1da177e4 LT |
766 | } |
767 | ||
768 | struct reiserfs_chown_buf { | |
bd4c625c LT |
769 | struct inode *inode; |
770 | struct dentry *xadir; | |
771 | struct iattr *attrs; | |
1da177e4 LT |
772 | }; |
773 | ||
774 | /* XXX: If there is a better way to do this, I'd love to hear about it */ | |
775 | static int | |
bd4c625c | 776 | reiserfs_chown_xattrs_filler(void *buf, const char *name, int namelen, |
afefdbb2 | 777 | loff_t offset, u64 ino, unsigned int d_type) |
1da177e4 | 778 | { |
bd4c625c LT |
779 | struct reiserfs_chown_buf *chown_buf = (struct reiserfs_chown_buf *)buf; |
780 | struct dentry *xafile, *xadir = chown_buf->xadir; | |
781 | struct iattr *attrs = chown_buf->attrs; | |
782 | int err = 0; | |
783 | ||
784 | xafile = lookup_one_len(name, xadir, namelen); | |
785 | if (IS_ERR(xafile)) | |
786 | return PTR_ERR(xafile); | |
787 | else if (!xafile->d_inode) { | |
788 | dput(xafile); | |
789 | return -ENODATA; | |
790 | } | |
791 | ||
792 | if (!S_ISDIR(xafile->d_inode->i_mode)) | |
793 | err = notify_change(xafile, attrs); | |
794 | dput(xafile); | |
795 | ||
796 | return err; | |
1da177e4 LT |
797 | } |
798 | ||
bd4c625c | 799 | int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs) |
1da177e4 | 800 | { |
bd4c625c LT |
801 | struct dentry *dir; |
802 | int err = 0; | |
803 | struct reiserfs_chown_buf buf; | |
804 | unsigned int ia_valid = attrs->ia_valid; | |
805 | ||
806 | /* Skip out, an xattr has no xattrs associated with it */ | |
807 | if (is_reiserfs_priv_object(inode) || | |
808 | get_inode_sd_version(inode) == STAT_DATA_V1 || | |
809 | !reiserfs_xattrs(inode->i_sb)) { | |
810 | return 0; | |
811 | } | |
812 | reiserfs_read_lock_xattrs(inode->i_sb); | |
813 | dir = open_xa_dir(inode, FL_READONLY); | |
814 | reiserfs_read_unlock_xattrs(inode->i_sb); | |
815 | if (IS_ERR(dir)) { | |
816 | if (PTR_ERR(dir) != -ENODATA) | |
817 | err = PTR_ERR(dir); | |
818 | goto out; | |
819 | } else if (!dir->d_inode) { | |
820 | dput(dir); | |
821 | goto out; | |
822 | } | |
823 | ||
bd4c625c LT |
824 | lock_kernel(); |
825 | ||
826 | attrs->ia_valid &= (ATTR_UID | ATTR_GID | ATTR_CTIME); | |
827 | buf.xadir = dir; | |
828 | buf.attrs = attrs; | |
829 | buf.inode = inode; | |
830 | ||
3227e14c | 831 | err = xattr_readdir(dir->d_inode, reiserfs_chown_xattrs_filler, &buf); |
bd4c625c LT |
832 | if (err) { |
833 | unlock_kernel(); | |
834 | goto out_dir; | |
835 | } | |
836 | ||
837 | err = notify_change(dir, attrs); | |
838 | unlock_kernel(); | |
839 | ||
840 | out_dir: | |
3227e14c | 841 | dput(dir); |
bd4c625c LT |
842 | |
843 | out: | |
844 | attrs->ia_valid = ia_valid; | |
845 | return err; | |
846 | } | |
1da177e4 LT |
847 | |
848 | /* Actual operations that are exported to VFS-land */ | |
849 | ||
850 | /* | |
851 | * Inode operation getxattr() | |
1b1dcc1b | 852 | * Preliminary locking: we down dentry->d_inode->i_mutex |
1da177e4 LT |
853 | */ |
854 | ssize_t | |
bd4c625c LT |
855 | reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer, |
856 | size_t size) | |
1da177e4 | 857 | { |
bd4c625c LT |
858 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
859 | int err; | |
860 | ||
861 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
862 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
863 | return -EOPNOTSUPP; | |
864 | ||
865 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
866 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
867 | err = xah->get(dentry->d_inode, name, buffer, size); | |
868 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
869 | reiserfs_read_unlock_xattr_i(dentry->d_inode); | |
870 | return err; | |
1da177e4 LT |
871 | } |
872 | ||
1da177e4 LT |
873 | /* |
874 | * Inode operation setxattr() | |
875 | * | |
1b1dcc1b | 876 | * dentry->d_inode->i_mutex down |
1da177e4 LT |
877 | */ |
878 | int | |
bd4c625c LT |
879 | reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
880 | size_t size, int flags) | |
1da177e4 | 881 | { |
bd4c625c LT |
882 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
883 | int err; | |
884 | int lock; | |
885 | ||
886 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
887 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
888 | return -EOPNOTSUPP; | |
889 | ||
bd4c625c LT |
890 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
891 | lock = !has_xattr_dir(dentry->d_inode); | |
892 | if (lock) | |
893 | reiserfs_write_lock_xattrs(dentry->d_sb); | |
894 | else | |
895 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
896 | err = xah->set(dentry->d_inode, name, value, size, flags); | |
897 | if (lock) | |
898 | reiserfs_write_unlock_xattrs(dentry->d_sb); | |
899 | else | |
900 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
901 | reiserfs_write_unlock_xattr_i(dentry->d_inode); | |
902 | return err; | |
1da177e4 LT |
903 | } |
904 | ||
905 | /* | |
906 | * Inode operation removexattr() | |
907 | * | |
1b1dcc1b | 908 | * dentry->d_inode->i_mutex down |
1da177e4 | 909 | */ |
bd4c625c | 910 | int reiserfs_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 911 | { |
bd4c625c LT |
912 | int err; |
913 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); | |
1da177e4 | 914 | |
bd4c625c LT |
915 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || |
916 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
917 | return -EOPNOTSUPP; | |
1da177e4 | 918 | |
bd4c625c LT |
919 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
920 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
1da177e4 | 921 | |
bd4c625c LT |
922 | /* Deletion pre-operation */ |
923 | if (xah->del) { | |
924 | err = xah->del(dentry->d_inode, name); | |
925 | if (err) | |
926 | goto out; | |
927 | } | |
1da177e4 | 928 | |
bd4c625c | 929 | err = reiserfs_xattr_del(dentry->d_inode, name); |
1da177e4 | 930 | |
bd4c625c LT |
931 | dentry->d_inode->i_ctime = CURRENT_TIME_SEC; |
932 | mark_inode_dirty(dentry->d_inode); | |
1da177e4 | 933 | |
bd4c625c LT |
934 | out: |
935 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
936 | reiserfs_write_unlock_xattr_i(dentry->d_inode); | |
937 | return err; | |
1da177e4 LT |
938 | } |
939 | ||
1da177e4 LT |
940 | /* This is what filldir will use: |
941 | * r_pos will always contain the amount of space required for the entire | |
942 | * list. If r_pos becomes larger than r_size, we need more space and we | |
943 | * return an error indicating this. If r_pos is less than r_size, then we've | |
944 | * filled the buffer successfully and we return success */ | |
945 | struct reiserfs_listxattr_buf { | |
bd4c625c LT |
946 | int r_pos; |
947 | int r_size; | |
948 | char *r_buf; | |
949 | struct inode *r_inode; | |
1da177e4 LT |
950 | }; |
951 | ||
952 | static int | |
bd4c625c | 953 | reiserfs_listxattr_filler(void *buf, const char *name, int namelen, |
afefdbb2 | 954 | loff_t offset, u64 ino, unsigned int d_type) |
1da177e4 | 955 | { |
bd4c625c LT |
956 | struct reiserfs_listxattr_buf *b = (struct reiserfs_listxattr_buf *)buf; |
957 | int len = 0; | |
958 | if (name[0] != '.' | |
959 | || (namelen != 1 && (name[1] != '.' || namelen != 2))) { | |
960 | struct reiserfs_xattr_handler *xah = | |
961 | find_xattr_handler_prefix(name); | |
962 | if (!xah) | |
963 | return 0; /* Unsupported xattr name, skip it */ | |
964 | ||
965 | /* We call ->list() twice because the operation isn't required to just | |
966 | * return the name back - we want to make sure we have enough space */ | |
967 | len += xah->list(b->r_inode, name, namelen, NULL); | |
968 | ||
969 | if (len) { | |
970 | if (b->r_pos + len + 1 <= b->r_size) { | |
971 | char *p = b->r_buf + b->r_pos; | |
972 | p += xah->list(b->r_inode, name, namelen, p); | |
973 | *p++ = '\0'; | |
974 | } | |
975 | b->r_pos += len + 1; | |
976 | } | |
977 | } | |
978 | ||
979 | return 0; | |
1da177e4 | 980 | } |
bd4c625c | 981 | |
1da177e4 LT |
982 | /* |
983 | * Inode operation listxattr() | |
984 | * | |
1b1dcc1b | 985 | * Preliminary locking: we down dentry->d_inode->i_mutex |
1da177e4 | 986 | */ |
bd4c625c | 987 | ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size) |
1da177e4 | 988 | { |
bd4c625c LT |
989 | struct dentry *dir; |
990 | int err = 0; | |
991 | struct reiserfs_listxattr_buf buf; | |
992 | ||
993 | if (!dentry->d_inode) | |
994 | return -EINVAL; | |
995 | ||
996 | if (!reiserfs_xattrs(dentry->d_sb) || | |
997 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
998 | return -EOPNOTSUPP; | |
999 | ||
1000 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
1001 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
1002 | dir = open_xa_dir(dentry->d_inode, FL_READONLY); | |
1003 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
1004 | if (IS_ERR(dir)) { | |
1005 | err = PTR_ERR(dir); | |
1006 | if (err == -ENODATA) | |
1007 | err = 0; /* Not an error if there aren't any xattrs */ | |
1008 | goto out; | |
1009 | } | |
1010 | ||
bd4c625c LT |
1011 | buf.r_buf = buffer; |
1012 | buf.r_size = buffer ? size : 0; | |
1013 | buf.r_pos = 0; | |
1014 | buf.r_inode = dentry->d_inode; | |
1015 | ||
1016 | REISERFS_I(dentry->d_inode)->i_flags |= i_has_xattr_dir; | |
1017 | ||
3227e14c | 1018 | err = xattr_readdir(dir->d_inode, reiserfs_listxattr_filler, &buf); |
bd4c625c LT |
1019 | if (err) |
1020 | goto out_dir; | |
1021 | ||
1022 | if (buf.r_pos > buf.r_size && buffer != NULL) | |
1023 | err = -ERANGE; | |
1024 | else | |
1025 | err = buf.r_pos; | |
1026 | ||
1027 | out_dir: | |
3227e14c | 1028 | dput(dir); |
bd4c625c LT |
1029 | |
1030 | out: | |
1031 | reiserfs_read_unlock_xattr_i(dentry->d_inode); | |
1032 | return err; | |
1da177e4 LT |
1033 | } |
1034 | ||
1035 | /* This is the implementation for the xattr plugin infrastructure */ | |
bcf11cbe | 1036 | static LIST_HEAD(xattr_handlers); |
1da177e4 LT |
1037 | static DEFINE_RWLOCK(handler_lock); |
1038 | ||
bd4c625c LT |
1039 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char |
1040 | *prefix) | |
1da177e4 | 1041 | { |
bd4c625c LT |
1042 | struct reiserfs_xattr_handler *xah = NULL; |
1043 | struct list_head *p; | |
1044 | ||
1045 | read_lock(&handler_lock); | |
1046 | list_for_each(p, &xattr_handlers) { | |
1047 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1048 | if (strncmp(xah->prefix, prefix, strlen(xah->prefix)) == 0) | |
1049 | break; | |
1050 | xah = NULL; | |
1051 | } | |
1052 | ||
1053 | read_unlock(&handler_lock); | |
1054 | return xah; | |
1da177e4 LT |
1055 | } |
1056 | ||
bd4c625c | 1057 | static void __unregister_handlers(void) |
1da177e4 | 1058 | { |
bd4c625c LT |
1059 | struct reiserfs_xattr_handler *xah; |
1060 | struct list_head *p, *tmp; | |
1da177e4 | 1061 | |
bd4c625c LT |
1062 | list_for_each_safe(p, tmp, &xattr_handlers) { |
1063 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1064 | if (xah->exit) | |
1065 | xah->exit(); | |
1da177e4 | 1066 | |
bd4c625c LT |
1067 | list_del_init(p); |
1068 | } | |
1069 | INIT_LIST_HEAD(&xattr_handlers); | |
1da177e4 LT |
1070 | } |
1071 | ||
bd4c625c | 1072 | int __init reiserfs_xattr_register_handlers(void) |
1da177e4 | 1073 | { |
bd4c625c LT |
1074 | int err = 0; |
1075 | struct reiserfs_xattr_handler *xah; | |
1076 | struct list_head *p; | |
1da177e4 | 1077 | |
bd4c625c | 1078 | write_lock(&handler_lock); |
1da177e4 | 1079 | |
bd4c625c LT |
1080 | /* If we're already initialized, nothing to do */ |
1081 | if (!list_empty(&xattr_handlers)) { | |
1082 | write_unlock(&handler_lock); | |
1083 | return 0; | |
1084 | } | |
1da177e4 | 1085 | |
bd4c625c LT |
1086 | /* Add the handlers */ |
1087 | list_add_tail(&user_handler.handlers, &xattr_handlers); | |
1088 | list_add_tail(&trusted_handler.handlers, &xattr_handlers); | |
1da177e4 | 1089 | #ifdef CONFIG_REISERFS_FS_SECURITY |
bd4c625c | 1090 | list_add_tail(&security_handler.handlers, &xattr_handlers); |
1da177e4 LT |
1091 | #endif |
1092 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL | |
bd4c625c LT |
1093 | list_add_tail(&posix_acl_access_handler.handlers, &xattr_handlers); |
1094 | list_add_tail(&posix_acl_default_handler.handlers, &xattr_handlers); | |
1da177e4 LT |
1095 | #endif |
1096 | ||
bd4c625c LT |
1097 | /* Run initializers, if available */ |
1098 | list_for_each(p, &xattr_handlers) { | |
1099 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1100 | if (xah->init) { | |
1101 | err = xah->init(); | |
1102 | if (err) { | |
1103 | list_del_init(p); | |
1104 | break; | |
1105 | } | |
1106 | } | |
1107 | } | |
1108 | ||
1109 | /* Clean up other handlers, if any failed */ | |
1110 | if (err) | |
1111 | __unregister_handlers(); | |
1112 | ||
1113 | write_unlock(&handler_lock); | |
1114 | return err; | |
1da177e4 LT |
1115 | } |
1116 | ||
bd4c625c | 1117 | void reiserfs_xattr_unregister_handlers(void) |
1da177e4 | 1118 | { |
bd4c625c LT |
1119 | write_lock(&handler_lock); |
1120 | __unregister_handlers(); | |
1121 | write_unlock(&handler_lock); | |
1da177e4 LT |
1122 | } |
1123 | ||
1124 | /* This will catch lookups from the fs root to .reiserfs_priv */ | |
1125 | static int | |
bd4c625c | 1126 | xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name) |
1da177e4 | 1127 | { |
bd4c625c LT |
1128 | struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root; |
1129 | if (name->len == priv_root->d_name.len && | |
1130 | name->hash == priv_root->d_name.hash && | |
1131 | !memcmp(name->name, priv_root->d_name.name, name->len)) { | |
1132 | return -ENOENT; | |
1133 | } else if (q1->len == name->len && | |
1134 | !memcmp(q1->name, name->name, name->len)) | |
1135 | return 0; | |
1136 | return 1; | |
1da177e4 LT |
1137 | } |
1138 | ||
1139 | static struct dentry_operations xattr_lookup_poison_ops = { | |
bd4c625c | 1140 | .d_compare = xattr_lookup_poison, |
1da177e4 LT |
1141 | }; |
1142 | ||
1da177e4 LT |
1143 | /* We need to take a copy of the mount flags since things like |
1144 | * MS_RDONLY don't get set until *after* we're called. | |
1145 | * mount_flags != mount_options */ | |
bd4c625c | 1146 | int reiserfs_xattr_init(struct super_block *s, int mount_flags) |
1da177e4 | 1147 | { |
bd4c625c LT |
1148 | int err = 0; |
1149 | ||
1150 | /* We need generation numbers to ensure that the oid mapping is correct | |
1151 | * v3.5 filesystems don't have them. */ | |
1152 | if (!old_format_only(s)) { | |
1153 | set_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1154 | } else if (reiserfs_xattrs_optional(s)) { | |
1155 | /* Old format filesystem, but optional xattrs have been enabled | |
1156 | * at mount time. Error out. */ | |
1157 | reiserfs_warning(s, "xattrs/ACLs not supported on pre v3.6 " | |
1158 | "format filesystem. Failing mount."); | |
1159 | err = -EOPNOTSUPP; | |
1160 | goto error; | |
1161 | } else { | |
1162 | /* Old format filesystem, but no optional xattrs have been enabled. This | |
1163 | * means we silently disable xattrs on the filesystem. */ | |
1164 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1165 | } | |
1166 | ||
1167 | /* If we don't have the privroot located yet - go find it */ | |
1168 | if (reiserfs_xattrs(s) && !REISERFS_SB(s)->priv_root) { | |
1169 | struct dentry *dentry; | |
1170 | dentry = lookup_one_len(PRIVROOT_NAME, s->s_root, | |
1171 | strlen(PRIVROOT_NAME)); | |
1172 | if (!IS_ERR(dentry)) { | |
1173 | if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) { | |
1174 | struct inode *inode = dentry->d_parent->d_inode; | |
75983928 JM |
1175 | mutex_lock_nested(&inode->i_mutex, |
1176 | I_MUTEX_XATTR); | |
bd4c625c | 1177 | err = inode->i_op->mkdir(inode, dentry, 0700); |
1b1dcc1b | 1178 | mutex_unlock(&inode->i_mutex); |
bd4c625c LT |
1179 | if (err) { |
1180 | dput(dentry); | |
1181 | dentry = NULL; | |
1182 | } | |
1183 | ||
1184 | if (dentry && dentry->d_inode) | |
1185 | reiserfs_warning(s, | |
1186 | "Created %s on %s - reserved for " | |
1187 | "xattr storage.", | |
1188 | PRIVROOT_NAME, | |
1189 | reiserfs_bdevname | |
1190 | (inode->i_sb)); | |
1191 | } else if (!dentry->d_inode) { | |
1192 | dput(dentry); | |
1193 | dentry = NULL; | |
1194 | } | |
1195 | } else | |
1196 | err = PTR_ERR(dentry); | |
1197 | ||
1198 | if (!err && dentry) { | |
1199 | s->s_root->d_op = &xattr_lookup_poison_ops; | |
1200 | reiserfs_mark_inode_private(dentry->d_inode); | |
1201 | REISERFS_SB(s)->priv_root = dentry; | |
1202 | } else if (!(mount_flags & MS_RDONLY)) { /* xattrs are unavailable */ | |
1203 | /* If we're read-only it just means that the dir hasn't been | |
1204 | * created. Not an error -- just no xattrs on the fs. We'll | |
1205 | * check again if we go read-write */ | |
1206 | reiserfs_warning(s, "xattrs/ACLs enabled and couldn't " | |
1207 | "find/create .reiserfs_priv. Failing mount."); | |
1208 | err = -EOPNOTSUPP; | |
1209 | } | |
1210 | } | |
1211 | ||
1212 | error: | |
1213 | /* This is only nonzero if there was an error initializing the xattr | |
1214 | * directory or if there is a condition where we don't support them. */ | |
1215 | if (err) { | |
1216 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1217 | clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt)); | |
1218 | clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt)); | |
1219 | } | |
1220 | ||
1221 | /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */ | |
1222 | s->s_flags = s->s_flags & ~MS_POSIXACL; | |
1223 | if (reiserfs_posixacl(s)) | |
1224 | s->s_flags |= MS_POSIXACL; | |
1225 | ||
1226 | return err; | |
1da177e4 LT |
1227 | } |
1228 | ||
ec191574 | 1229 | static int reiserfs_check_acl(struct inode *inode, int mask) |
1da177e4 | 1230 | { |
ec191574 CH |
1231 | struct posix_acl *acl; |
1232 | int error = -EAGAIN; /* do regular unix permission checks by default */ | |
1da177e4 | 1233 | |
ec191574 CH |
1234 | reiserfs_read_lock_xattr_i(inode); |
1235 | reiserfs_read_lock_xattrs(inode->i_sb); | |
c87d0c07 | 1236 | |
ec191574 | 1237 | acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS); |
c87d0c07 | 1238 | |
ec191574 CH |
1239 | reiserfs_read_unlock_xattrs(inode->i_sb); |
1240 | reiserfs_read_unlock_xattr_i(inode); | |
bd4c625c | 1241 | |
ec191574 CH |
1242 | if (acl) { |
1243 | if (!IS_ERR(acl)) { | |
1244 | error = posix_acl_permission(inode, acl, mask); | |
bd4c625c | 1245 | posix_acl_release(acl); |
ec191574 CH |
1246 | } else if (PTR_ERR(acl) != -ENODATA) |
1247 | error = PTR_ERR(acl); | |
1da177e4 LT |
1248 | } |
1249 | ||
ec191574 CH |
1250 | return error; |
1251 | } | |
1da177e4 | 1252 | |
e6305c43 | 1253 | int reiserfs_permission(struct inode *inode, int mask) |
ec191574 | 1254 | { |
1da177e4 | 1255 | /* |
ec191574 CH |
1256 | * We don't do permission checks on the internal objects. |
1257 | * Permissions are determined by the "owning" object. | |
1da177e4 | 1258 | */ |
ec191574 CH |
1259 | if (is_reiserfs_priv_object(inode)) |
1260 | return 0; | |
1da177e4 LT |
1261 | |
1262 | /* | |
ec191574 | 1263 | * Stat data v1 doesn't support ACLs. |
1da177e4 | 1264 | */ |
ec191574 CH |
1265 | if (get_inode_sd_version(inode) == STAT_DATA_V1) |
1266 | return generic_permission(inode, mask, NULL); | |
1267 | else | |
1268 | return generic_permission(inode, mask, reiserfs_check_acl); | |
1da177e4 | 1269 | } |