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> | |
33 | #include <linux/dcache.h> | |
34 | #include <linux/namei.h> | |
35 | #include <linux/errno.h> | |
36 | #include <linux/fs.h> | |
37 | #include <linux/file.h> | |
38 | #include <linux/pagemap.h> | |
39 | #include <linux/xattr.h> | |
40 | #include <linux/reiserfs_xattr.h> | |
41 | #include <linux/reiserfs_acl.h> | |
1da177e4 LT |
42 | #include <asm/uaccess.h> |
43 | #include <asm/checksum.h> | |
44 | #include <linux/smp_lock.h> | |
45 | #include <linux/stat.h> | |
46 | #include <asm/semaphore.h> | |
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 | |
bd4c625c | 56 | static struct dentry *create_xa_root(struct super_block *sb) |
1da177e4 | 57 | { |
bd4c625c LT |
58 | struct dentry *privroot = dget(REISERFS_SB(sb)->priv_root); |
59 | struct dentry *xaroot; | |
60 | ||
61 | /* This needs to be created at mount-time */ | |
62 | if (!privroot) | |
63 | return ERR_PTR(-EOPNOTSUPP); | |
64 | ||
65 | xaroot = lookup_one_len(XAROOT_NAME, privroot, strlen(XAROOT_NAME)); | |
66 | if (IS_ERR(xaroot)) { | |
67 | goto out; | |
68 | } else if (!xaroot->d_inode) { | |
69 | int err; | |
1b1dcc1b | 70 | mutex_lock(&privroot->d_inode->i_mutex); |
bd4c625c LT |
71 | err = |
72 | privroot->d_inode->i_op->mkdir(privroot->d_inode, xaroot, | |
73 | 0700); | |
1b1dcc1b | 74 | mutex_unlock(&privroot->d_inode->i_mutex); |
bd4c625c LT |
75 | |
76 | if (err) { | |
77 | dput(xaroot); | |
78 | dput(privroot); | |
79 | return ERR_PTR(err); | |
80 | } | |
81 | REISERFS_SB(sb)->xattr_root = dget(xaroot); | |
82 | } | |
83 | ||
84 | out: | |
85 | dput(privroot); | |
86 | return xaroot; | |
1da177e4 LT |
87 | } |
88 | ||
89 | /* This will return a dentry, or error, refering to the xa root directory. | |
90 | * If the xa root doesn't exist yet, the dentry will be returned without | |
91 | * an associated inode. This dentry can be used with ->mkdir to create | |
92 | * the xa directory. */ | |
bd4c625c | 93 | static struct dentry *__get_xa_root(struct super_block *s) |
1da177e4 | 94 | { |
bd4c625c LT |
95 | struct dentry *privroot = dget(REISERFS_SB(s)->priv_root); |
96 | struct dentry *xaroot = NULL; | |
97 | ||
98 | if (IS_ERR(privroot) || !privroot) | |
99 | return privroot; | |
100 | ||
101 | xaroot = lookup_one_len(XAROOT_NAME, privroot, strlen(XAROOT_NAME)); | |
102 | if (IS_ERR(xaroot)) { | |
103 | goto out; | |
104 | } else if (!xaroot->d_inode) { | |
105 | dput(xaroot); | |
106 | xaroot = NULL; | |
107 | goto out; | |
108 | } | |
109 | ||
110 | REISERFS_SB(s)->xattr_root = dget(xaroot); | |
111 | ||
112 | out: | |
113 | dput(privroot); | |
114 | return xaroot; | |
1da177e4 LT |
115 | } |
116 | ||
117 | /* Returns the dentry (or NULL) referring to the root of the extended | |
4a4efbde MM |
118 | * attribute directory tree. If it has already been retrieved, it is used. |
119 | * Otherwise, we attempt to retrieve it from disk. It may also return | |
1da177e4 LT |
120 | * a pointer-encoded error. |
121 | */ | |
bd4c625c | 122 | static inline struct dentry *get_xa_root(struct super_block *s) |
1da177e4 | 123 | { |
bd4c625c | 124 | struct dentry *dentry = dget(REISERFS_SB(s)->xattr_root); |
1da177e4 | 125 | |
bd4c625c LT |
126 | if (!dentry) |
127 | dentry = __get_xa_root(s); | |
1da177e4 | 128 | |
bd4c625c | 129 | return dentry; |
1da177e4 LT |
130 | } |
131 | ||
132 | /* Opens the directory corresponding to the inode's extended attribute store. | |
133 | * If flags allow, the tree to the directory may be created. If creation is | |
134 | * prohibited, -ENODATA is returned. */ | |
bd4c625c | 135 | static struct dentry *open_xa_dir(const struct inode *inode, int flags) |
1da177e4 | 136 | { |
bd4c625c LT |
137 | struct dentry *xaroot, *xadir; |
138 | char namebuf[17]; | |
139 | ||
140 | xaroot = get_xa_root(inode->i_sb); | |
141 | if (IS_ERR(xaroot)) { | |
142 | return xaroot; | |
143 | } else if (!xaroot) { | |
144 | if (flags == 0 || flags & XATTR_CREATE) { | |
145 | xaroot = create_xa_root(inode->i_sb); | |
146 | if (IS_ERR(xaroot)) | |
147 | return xaroot; | |
148 | } | |
149 | if (!xaroot) | |
150 | return ERR_PTR(-ENODATA); | |
151 | } | |
152 | ||
153 | /* ok, we have xaroot open */ | |
154 | ||
155 | snprintf(namebuf, sizeof(namebuf), "%X.%X", | |
156 | le32_to_cpu(INODE_PKEY(inode)->k_objectid), | |
157 | inode->i_generation); | |
158 | xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf)); | |
159 | if (IS_ERR(xadir)) { | |
160 | dput(xaroot); | |
161 | return xadir; | |
162 | } | |
163 | ||
164 | if (!xadir->d_inode) { | |
165 | int err; | |
166 | if (flags == 0 || flags & XATTR_CREATE) { | |
167 | /* Although there is nothing else trying to create this directory, | |
168 | * another directory with the same hash may be created, so we need | |
169 | * to protect against that */ | |
170 | err = | |
171 | xaroot->d_inode->i_op->mkdir(xaroot->d_inode, xadir, | |
172 | 0700); | |
173 | if (err) { | |
174 | dput(xaroot); | |
175 | dput(xadir); | |
176 | return ERR_PTR(err); | |
177 | } | |
178 | } | |
179 | if (!xadir->d_inode) { | |
180 | dput(xaroot); | |
181 | dput(xadir); | |
182 | return ERR_PTR(-ENODATA); | |
183 | } | |
184 | } | |
185 | ||
186 | dput(xaroot); | |
187 | return xadir; | |
1da177e4 LT |
188 | } |
189 | ||
190 | /* Returns a dentry corresponding to a specific extended attribute file | |
191 | * for the inode. If flags allow, the file is created. Otherwise, a | |
192 | * valid or negative dentry, or an error is returned. */ | |
bd4c625c LT |
193 | static struct dentry *get_xa_file_dentry(const struct inode *inode, |
194 | const char *name, int flags) | |
1da177e4 | 195 | { |
bd4c625c LT |
196 | struct dentry *xadir, *xafile; |
197 | int err = 0; | |
198 | ||
199 | xadir = open_xa_dir(inode, flags); | |
200 | if (IS_ERR(xadir)) { | |
201 | return ERR_PTR(PTR_ERR(xadir)); | |
202 | } else if (xadir && !xadir->d_inode) { | |
203 | dput(xadir); | |
204 | return ERR_PTR(-ENODATA); | |
205 | } | |
206 | ||
207 | xafile = lookup_one_len(name, xadir, strlen(name)); | |
208 | if (IS_ERR(xafile)) { | |
209 | dput(xadir); | |
210 | return ERR_PTR(PTR_ERR(xafile)); | |
211 | } | |
212 | ||
213 | if (xafile->d_inode) { /* file exists */ | |
214 | if (flags & XATTR_CREATE) { | |
215 | err = -EEXIST; | |
216 | dput(xafile); | |
217 | goto out; | |
218 | } | |
219 | } else if (flags & XATTR_REPLACE || flags & FL_READONLY) { | |
220 | goto out; | |
221 | } else { | |
1b1dcc1b | 222 | /* inode->i_mutex is down, so nothing else can try to create |
bd4c625c LT |
223 | * the same xattr */ |
224 | err = xadir->d_inode->i_op->create(xadir->d_inode, xafile, | |
225 | 0700 | S_IFREG, NULL); | |
226 | ||
227 | if (err) { | |
228 | dput(xafile); | |
229 | goto out; | |
230 | } | |
231 | } | |
1da177e4 | 232 | |
bd4c625c LT |
233 | out: |
234 | dput(xadir); | |
235 | if (err) | |
236 | xafile = ERR_PTR(err); | |
237 | return xafile; | |
238 | } | |
1da177e4 LT |
239 | |
240 | /* Opens a file pointer to the attribute associated with inode */ | |
bd4c625c LT |
241 | static struct file *open_xa_file(const struct inode *inode, const char *name, |
242 | int flags) | |
1da177e4 | 243 | { |
bd4c625c LT |
244 | struct dentry *xafile; |
245 | struct file *fp; | |
246 | ||
247 | xafile = get_xa_file_dentry(inode, name, flags); | |
248 | if (IS_ERR(xafile)) | |
249 | return ERR_PTR(PTR_ERR(xafile)); | |
250 | else if (!xafile->d_inode) { | |
251 | dput(xafile); | |
252 | return ERR_PTR(-ENODATA); | |
253 | } | |
1da177e4 | 254 | |
bd4c625c LT |
255 | fp = dentry_open(xafile, NULL, O_RDWR); |
256 | /* dentry_open dputs the dentry if it fails */ | |
1da177e4 | 257 | |
bd4c625c | 258 | return fp; |
1da177e4 LT |
259 | } |
260 | ||
1da177e4 LT |
261 | /* |
262 | * this is very similar to fs/reiserfs/dir.c:reiserfs_readdir, but | |
263 | * we need to drop the path before calling the filldir struct. That | |
264 | * would be a big performance hit to the non-xattr case, so I've copied | |
265 | * the whole thing for now. --clm | |
266 | * | |
267 | * the big difference is that I go backwards through the directory, | |
268 | * and don't mess with f->f_pos, but the idea is the same. Do some | |
269 | * action on each and every entry in the directory. | |
270 | * | |
1b1dcc1b | 271 | * we're called with i_mutex held, so there are no worries about the directory |
1da177e4 LT |
272 | * changing underneath us. |
273 | */ | |
bd4c625c | 274 | static int __xattr_readdir(struct file *filp, void *dirent, filldir_t filldir) |
1da177e4 | 275 | { |
bd4c625c LT |
276 | struct inode *inode = filp->f_dentry->d_inode; |
277 | struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */ | |
278 | INITIALIZE_PATH(path_to_entry); | |
279 | struct buffer_head *bh; | |
280 | int entry_num; | |
281 | struct item_head *ih, tmp_ih; | |
282 | int search_res; | |
283 | char *local_buf; | |
284 | loff_t next_pos; | |
285 | char small_buf[32]; /* avoid kmalloc if we can */ | |
286 | struct reiserfs_de_head *deh; | |
287 | int d_reclen; | |
288 | char *d_name; | |
289 | off_t d_off; | |
290 | ino_t d_ino; | |
291 | struct reiserfs_dir_entry de; | |
292 | ||
293 | /* form key for search the next directory entry using f_pos field of | |
294 | file structure */ | |
295 | next_pos = max_reiserfs_offset(inode); | |
296 | ||
297 | while (1) { | |
298 | research: | |
299 | if (next_pos <= DOT_DOT_OFFSET) | |
300 | break; | |
301 | make_cpu_key(&pos_key, inode, next_pos, TYPE_DIRENTRY, 3); | |
302 | ||
303 | search_res = | |
304 | search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry, | |
305 | &de); | |
306 | if (search_res == IO_ERROR) { | |
307 | // FIXME: we could just skip part of directory which could | |
308 | // not be read | |
309 | pathrelse(&path_to_entry); | |
310 | return -EIO; | |
311 | } | |
1da177e4 | 312 | |
bd4c625c LT |
313 | if (search_res == NAME_NOT_FOUND) |
314 | de.de_entry_num--; | |
1da177e4 | 315 | |
bd4c625c LT |
316 | set_de_name_and_namelen(&de); |
317 | entry_num = de.de_entry_num; | |
318 | deh = &(de.de_deh[entry_num]); | |
1da177e4 | 319 | |
bd4c625c LT |
320 | bh = de.de_bh; |
321 | ih = de.de_ih; | |
1da177e4 | 322 | |
bd4c625c LT |
323 | if (!is_direntry_le_ih(ih)) { |
324 | reiserfs_warning(inode->i_sb, "not direntry %h", ih); | |
325 | break; | |
326 | } | |
327 | copy_item_head(&tmp_ih, ih); | |
1da177e4 | 328 | |
bd4c625c LT |
329 | /* we must have found item, that is item of this directory, */ |
330 | RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key), | |
331 | "vs-9000: found item %h does not match to dir we readdir %K", | |
332 | ih, &pos_key); | |
1da177e4 | 333 | |
bd4c625c LT |
334 | if (deh_offset(deh) <= DOT_DOT_OFFSET) { |
335 | break; | |
336 | } | |
1da177e4 | 337 | |
bd4c625c LT |
338 | /* look for the previous entry in the directory */ |
339 | next_pos = deh_offset(deh) - 1; | |
1da177e4 | 340 | |
bd4c625c LT |
341 | if (!de_visible(deh)) |
342 | /* it is hidden entry */ | |
343 | continue; | |
1da177e4 | 344 | |
bd4c625c LT |
345 | d_reclen = entry_length(bh, ih, entry_num); |
346 | d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh); | |
347 | d_off = deh_offset(deh); | |
348 | d_ino = deh_objectid(deh); | |
1da177e4 | 349 | |
bd4c625c LT |
350 | if (!d_name[d_reclen - 1]) |
351 | d_reclen = strlen(d_name); | |
1da177e4 | 352 | |
bd4c625c LT |
353 | if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)) { |
354 | /* too big to send back to VFS */ | |
355 | continue; | |
356 | } | |
1da177e4 | 357 | |
bd4c625c LT |
358 | /* Ignore the .reiserfs_priv entry */ |
359 | if (reiserfs_xattrs(inode->i_sb) && | |
360 | !old_format_only(inode->i_sb) && | |
361 | deh_objectid(deh) == | |
362 | le32_to_cpu(INODE_PKEY | |
363 | (REISERFS_SB(inode->i_sb)->priv_root->d_inode)-> | |
364 | k_objectid)) | |
365 | continue; | |
366 | ||
367 | if (d_reclen <= 32) { | |
368 | local_buf = small_buf; | |
369 | } else { | |
370 | local_buf = | |
371 | reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb); | |
372 | if (!local_buf) { | |
373 | pathrelse(&path_to_entry); | |
374 | return -ENOMEM; | |
375 | } | |
376 | if (item_moved(&tmp_ih, &path_to_entry)) { | |
377 | reiserfs_kfree(local_buf, d_reclen, | |
378 | inode->i_sb); | |
379 | ||
380 | /* sigh, must retry. Do this same offset again */ | |
381 | next_pos = d_off; | |
382 | goto research; | |
383 | } | |
384 | } | |
1da177e4 | 385 | |
bd4c625c LT |
386 | // Note, that we copy name to user space via temporary |
387 | // buffer (local_buf) because filldir will block if | |
388 | // user space buffer is swapped out. At that time | |
389 | // entry can move to somewhere else | |
390 | memcpy(local_buf, d_name, d_reclen); | |
1da177e4 | 391 | |
bd4c625c LT |
392 | /* the filldir function might need to start transactions, |
393 | * or do who knows what. Release the path now that we've | |
394 | * copied all the important stuff out of the deh | |
395 | */ | |
396 | pathrelse(&path_to_entry); | |
397 | ||
398 | if (filldir(dirent, local_buf, d_reclen, d_off, d_ino, | |
399 | DT_UNKNOWN) < 0) { | |
400 | if (local_buf != small_buf) { | |
401 | reiserfs_kfree(local_buf, d_reclen, | |
402 | inode->i_sb); | |
403 | } | |
404 | goto end; | |
405 | } | |
406 | if (local_buf != small_buf) { | |
407 | reiserfs_kfree(local_buf, d_reclen, inode->i_sb); | |
408 | } | |
409 | } /* while */ | |
1da177e4 | 410 | |
bd4c625c LT |
411 | end: |
412 | pathrelse(&path_to_entry); | |
413 | return 0; | |
1da177e4 LT |
414 | } |
415 | ||
416 | /* | |
417 | * this could be done with dedicated readdir ops for the xattr files, | |
418 | * but I want to get something working asap | |
419 | * this is stolen from vfs_readdir | |
420 | * | |
421 | */ | |
422 | static | |
423 | int xattr_readdir(struct file *file, filldir_t filler, void *buf) | |
424 | { | |
bd4c625c LT |
425 | struct inode *inode = file->f_dentry->d_inode; |
426 | int res = -ENOTDIR; | |
427 | if (!file->f_op || !file->f_op->readdir) | |
428 | goto out; | |
1b1dcc1b | 429 | mutex_lock(&inode->i_mutex); |
1da177e4 | 430 | // down(&inode->i_zombie); |
bd4c625c LT |
431 | res = -ENOENT; |
432 | if (!IS_DEADDIR(inode)) { | |
433 | lock_kernel(); | |
434 | res = __xattr_readdir(file, buf, filler); | |
435 | unlock_kernel(); | |
436 | } | |
1da177e4 | 437 | // up(&inode->i_zombie); |
1b1dcc1b | 438 | mutex_unlock(&inode->i_mutex); |
bd4c625c LT |
439 | out: |
440 | return res; | |
1da177e4 LT |
441 | } |
442 | ||
1da177e4 | 443 | /* Internal operations on file data */ |
bd4c625c | 444 | static inline void reiserfs_put_page(struct page *page) |
1da177e4 | 445 | { |
bd4c625c LT |
446 | kunmap(page); |
447 | page_cache_release(page); | |
1da177e4 LT |
448 | } |
449 | ||
bd4c625c | 450 | static struct page *reiserfs_get_page(struct inode *dir, unsigned long n) |
1da177e4 | 451 | { |
bd4c625c LT |
452 | struct address_space *mapping = dir->i_mapping; |
453 | struct page *page; | |
454 | /* We can deadlock if we try to free dentries, | |
455 | and an unlink/rmdir has just occured - GFP_NOFS avoids this */ | |
c4cdd038 | 456 | mapping_set_gfp_mask(mapping, GFP_NOFS); |
bd4c625c LT |
457 | page = read_cache_page(mapping, n, |
458 | (filler_t *) mapping->a_ops->readpage, NULL); | |
459 | if (!IS_ERR(page)) { | |
460 | wait_on_page_locked(page); | |
461 | kmap(page); | |
462 | if (!PageUptodate(page)) | |
463 | goto fail; | |
464 | ||
465 | if (PageError(page)) | |
466 | goto fail; | |
467 | } | |
468 | return page; | |
469 | ||
470 | fail: | |
471 | reiserfs_put_page(page); | |
472 | return ERR_PTR(-EIO); | |
1da177e4 LT |
473 | } |
474 | ||
bd4c625c | 475 | static inline __u32 xattr_hash(const char *msg, int len) |
1da177e4 | 476 | { |
bd4c625c | 477 | return csum_partial(msg, len, 0); |
1da177e4 LT |
478 | } |
479 | ||
480 | /* Generic extended attribute operations that can be used by xa plugins */ | |
481 | ||
482 | /* | |
1b1dcc1b | 483 | * inode->i_mutex: down |
1da177e4 LT |
484 | */ |
485 | int | |
bd4c625c LT |
486 | reiserfs_xattr_set(struct inode *inode, const char *name, const void *buffer, |
487 | size_t buffer_size, int flags) | |
1da177e4 | 488 | { |
bd4c625c LT |
489 | int err = 0; |
490 | struct file *fp; | |
491 | struct page *page; | |
492 | char *data; | |
493 | struct address_space *mapping; | |
494 | size_t file_pos = 0; | |
495 | size_t buffer_pos = 0; | |
496 | struct inode *xinode; | |
497 | struct iattr newattrs; | |
498 | __u32 xahash = 0; | |
499 | ||
bd4c625c LT |
500 | if (get_inode_sd_version(inode) == STAT_DATA_V1) |
501 | return -EOPNOTSUPP; | |
502 | ||
503 | /* Empty xattrs are ok, they're just empty files, no hash */ | |
504 | if (buffer && buffer_size) | |
505 | xahash = xattr_hash(buffer, buffer_size); | |
506 | ||
507 | open_file: | |
508 | fp = open_xa_file(inode, name, flags); | |
509 | if (IS_ERR(fp)) { | |
510 | err = PTR_ERR(fp); | |
511 | goto out; | |
512 | } | |
513 | ||
514 | xinode = fp->f_dentry->d_inode; | |
515 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; | |
516 | ||
517 | /* we need to copy it off.. */ | |
518 | if (xinode->i_nlink > 1) { | |
519 | fput(fp); | |
520 | err = reiserfs_xattr_del(inode, name); | |
521 | if (err < 0) | |
522 | goto out; | |
523 | /* We just killed the old one, we're not replacing anymore */ | |
524 | if (flags & XATTR_REPLACE) | |
525 | flags &= ~XATTR_REPLACE; | |
526 | goto open_file; | |
527 | } | |
528 | ||
529 | /* Resize it so we're ok to write there */ | |
530 | newattrs.ia_size = buffer_size; | |
531 | newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME; | |
1b1dcc1b | 532 | mutex_lock(&xinode->i_mutex); |
bd4c625c LT |
533 | err = notify_change(fp->f_dentry, &newattrs); |
534 | if (err) | |
535 | goto out_filp; | |
536 | ||
537 | mapping = xinode->i_mapping; | |
538 | while (buffer_pos < buffer_size || buffer_pos == 0) { | |
539 | size_t chunk; | |
540 | size_t skip = 0; | |
541 | size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1)); | |
542 | if (buffer_size - buffer_pos > PAGE_CACHE_SIZE) | |
543 | chunk = PAGE_CACHE_SIZE; | |
544 | else | |
545 | chunk = buffer_size - buffer_pos; | |
546 | ||
547 | page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT); | |
548 | if (IS_ERR(page)) { | |
549 | err = PTR_ERR(page); | |
550 | goto out_filp; | |
551 | } | |
552 | ||
553 | lock_page(page); | |
554 | data = page_address(page); | |
555 | ||
556 | if (file_pos == 0) { | |
557 | struct reiserfs_xattr_header *rxh; | |
558 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
559 | if (chunk + skip > PAGE_CACHE_SIZE) | |
560 | chunk = PAGE_CACHE_SIZE - skip; | |
561 | rxh = (struct reiserfs_xattr_header *)data; | |
562 | rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC); | |
563 | rxh->h_hash = cpu_to_le32(xahash); | |
564 | } | |
565 | ||
566 | err = mapping->a_ops->prepare_write(fp, page, page_offset, | |
567 | page_offset + chunk + skip); | |
568 | if (!err) { | |
569 | if (buffer) | |
570 | memcpy(data + skip, buffer + buffer_pos, chunk); | |
571 | err = | |
572 | mapping->a_ops->commit_write(fp, page, page_offset, | |
573 | page_offset + chunk + | |
574 | skip); | |
575 | } | |
576 | unlock_page(page); | |
577 | reiserfs_put_page(page); | |
578 | buffer_pos += chunk; | |
579 | file_pos += chunk; | |
580 | skip = 0; | |
581 | if (err || buffer_size == 0 || !buffer) | |
582 | break; | |
583 | } | |
584 | ||
585 | /* We can't mark the inode dirty if it's not hashed. This is the case | |
586 | * when we're inheriting the default ACL. If we dirty it, the inode | |
587 | * gets marked dirty, but won't (ever) make it onto the dirty list until | |
588 | * it's synced explicitly to clear I_DIRTY. This is bad. */ | |
589 | if (!hlist_unhashed(&inode->i_hash)) { | |
590 | inode->i_ctime = CURRENT_TIME_SEC; | |
591 | mark_inode_dirty(inode); | |
1da177e4 | 592 | } |
bd4c625c LT |
593 | |
594 | out_filp: | |
1b1dcc1b | 595 | mutex_unlock(&xinode->i_mutex); |
bd4c625c LT |
596 | fput(fp); |
597 | ||
598 | out: | |
599 | return err; | |
1da177e4 LT |
600 | } |
601 | ||
602 | /* | |
1b1dcc1b | 603 | * inode->i_mutex: down |
1da177e4 LT |
604 | */ |
605 | int | |
bd4c625c LT |
606 | reiserfs_xattr_get(const struct inode *inode, const char *name, void *buffer, |
607 | size_t buffer_size) | |
1da177e4 | 608 | { |
bd4c625c LT |
609 | ssize_t err = 0; |
610 | struct file *fp; | |
611 | size_t isize; | |
612 | size_t file_pos = 0; | |
613 | size_t buffer_pos = 0; | |
614 | struct page *page; | |
615 | struct inode *xinode; | |
616 | __u32 hash = 0; | |
617 | ||
618 | if (name == NULL) | |
619 | return -EINVAL; | |
620 | ||
621 | /* We can't have xattrs attached to v1 items since they don't have | |
622 | * generation numbers */ | |
623 | if (get_inode_sd_version(inode) == STAT_DATA_V1) | |
624 | return -EOPNOTSUPP; | |
625 | ||
626 | fp = open_xa_file(inode, name, FL_READONLY); | |
627 | if (IS_ERR(fp)) { | |
628 | err = PTR_ERR(fp); | |
629 | goto out; | |
630 | } | |
631 | ||
632 | xinode = fp->f_dentry->d_inode; | |
633 | isize = xinode->i_size; | |
634 | REISERFS_I(inode)->i_flags |= i_has_xattr_dir; | |
635 | ||
636 | /* Just return the size needed */ | |
637 | if (buffer == NULL) { | |
638 | err = isize - sizeof(struct reiserfs_xattr_header); | |
639 | goto out_dput; | |
640 | } | |
641 | ||
642 | if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) { | |
643 | err = -ERANGE; | |
644 | goto out_dput; | |
645 | } | |
646 | ||
647 | while (file_pos < isize) { | |
648 | size_t chunk; | |
649 | char *data; | |
650 | size_t skip = 0; | |
651 | if (isize - file_pos > PAGE_CACHE_SIZE) | |
652 | chunk = PAGE_CACHE_SIZE; | |
653 | else | |
654 | chunk = isize - file_pos; | |
655 | ||
656 | page = reiserfs_get_page(xinode, file_pos >> PAGE_CACHE_SHIFT); | |
657 | if (IS_ERR(page)) { | |
658 | err = PTR_ERR(page); | |
659 | goto out_dput; | |
660 | } | |
661 | ||
662 | lock_page(page); | |
663 | data = page_address(page); | |
664 | if (file_pos == 0) { | |
665 | struct reiserfs_xattr_header *rxh = | |
666 | (struct reiserfs_xattr_header *)data; | |
667 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
668 | chunk -= skip; | |
669 | /* Magic doesn't match up.. */ | |
670 | if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) { | |
671 | unlock_page(page); | |
672 | reiserfs_put_page(page); | |
673 | reiserfs_warning(inode->i_sb, | |
674 | "Invalid magic for xattr (%s) " | |
675 | "associated with %k", name, | |
676 | INODE_PKEY(inode)); | |
677 | err = -EIO; | |
678 | goto out_dput; | |
679 | } | |
680 | hash = le32_to_cpu(rxh->h_hash); | |
681 | } | |
682 | memcpy(buffer + buffer_pos, data + skip, chunk); | |
683 | unlock_page(page); | |
684 | reiserfs_put_page(page); | |
685 | file_pos += chunk; | |
686 | buffer_pos += chunk; | |
687 | skip = 0; | |
688 | } | |
689 | err = isize - sizeof(struct reiserfs_xattr_header); | |
690 | ||
691 | if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) != | |
692 | hash) { | |
693 | reiserfs_warning(inode->i_sb, | |
694 | "Invalid hash for xattr (%s) associated " | |
695 | "with %k", name, INODE_PKEY(inode)); | |
696 | err = -EIO; | |
697 | } | |
698 | ||
699 | out_dput: | |
700 | fput(fp); | |
701 | ||
702 | out: | |
703 | return err; | |
1da177e4 LT |
704 | } |
705 | ||
706 | static int | |
bd4c625c | 707 | __reiserfs_xattr_del(struct dentry *xadir, const char *name, int namelen) |
1da177e4 | 708 | { |
bd4c625c LT |
709 | struct dentry *dentry; |
710 | struct inode *dir = xadir->d_inode; | |
711 | int err = 0; | |
712 | ||
713 | dentry = lookup_one_len(name, xadir, namelen); | |
714 | if (IS_ERR(dentry)) { | |
715 | err = PTR_ERR(dentry); | |
716 | goto out; | |
717 | } else if (!dentry->d_inode) { | |
718 | err = -ENODATA; | |
719 | goto out_file; | |
720 | } | |
721 | ||
722 | /* Skip directories.. */ | |
723 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
724 | goto out_file; | |
725 | ||
726 | if (!is_reiserfs_priv_object(dentry->d_inode)) { | |
727 | reiserfs_warning(dir->i_sb, "OID %08x [%.*s/%.*s] doesn't have " | |
728 | "priv flag set [parent is %sset].", | |
729 | le32_to_cpu(INODE_PKEY(dentry->d_inode)-> | |
730 | k_objectid), xadir->d_name.len, | |
731 | xadir->d_name.name, namelen, name, | |
732 | is_reiserfs_priv_object(xadir-> | |
733 | d_inode) ? "" : | |
734 | "not "); | |
735 | dput(dentry); | |
736 | return -EIO; | |
737 | } | |
1da177e4 | 738 | |
bd4c625c LT |
739 | err = dir->i_op->unlink(dir, dentry); |
740 | if (!err) | |
741 | d_delete(dentry); | |
1da177e4 | 742 | |
bd4c625c LT |
743 | out_file: |
744 | dput(dentry); | |
745 | ||
746 | out: | |
747 | return err; | |
748 | } | |
749 | ||
750 | int reiserfs_xattr_del(struct inode *inode, const char *name) | |
1da177e4 | 751 | { |
bd4c625c LT |
752 | struct dentry *dir; |
753 | int err; | |
1da177e4 | 754 | |
bd4c625c LT |
755 | dir = open_xa_dir(inode, FL_READONLY); |
756 | if (IS_ERR(dir)) { | |
757 | err = PTR_ERR(dir); | |
758 | goto out; | |
759 | } | |
1da177e4 | 760 | |
bd4c625c LT |
761 | err = __reiserfs_xattr_del(dir, name, strlen(name)); |
762 | dput(dir); | |
1da177e4 | 763 | |
bd4c625c LT |
764 | if (!err) { |
765 | inode->i_ctime = CURRENT_TIME_SEC; | |
766 | mark_inode_dirty(inode); | |
767 | } | |
1da177e4 | 768 | |
bd4c625c LT |
769 | out: |
770 | return err; | |
1da177e4 LT |
771 | } |
772 | ||
773 | /* The following are side effects of other operations that aren't explicitly | |
774 | * modifying extended attributes. This includes operations such as permissions | |
775 | * or ownership changes, object deletions, etc. */ | |
776 | ||
777 | static int | |
bd4c625c LT |
778 | reiserfs_delete_xattrs_filler(void *buf, const char *name, int namelen, |
779 | loff_t offset, ino_t ino, unsigned int d_type) | |
1da177e4 | 780 | { |
bd4c625c | 781 | struct dentry *xadir = (struct dentry *)buf; |
1da177e4 | 782 | |
bd4c625c | 783 | return __reiserfs_xattr_del(xadir, name, namelen); |
1da177e4 LT |
784 | |
785 | } | |
786 | ||
1b1dcc1b | 787 | /* This is called w/ inode->i_mutex downed */ |
bd4c625c | 788 | int reiserfs_delete_xattrs(struct inode *inode) |
1da177e4 | 789 | { |
bd4c625c LT |
790 | struct file *fp; |
791 | struct dentry *dir, *root; | |
792 | int err = 0; | |
793 | ||
794 | /* Skip out, an xattr has no xattrs associated with it */ | |
795 | if (is_reiserfs_priv_object(inode) || | |
796 | get_inode_sd_version(inode) == STAT_DATA_V1 || | |
797 | !reiserfs_xattrs(inode->i_sb)) { | |
798 | return 0; | |
799 | } | |
800 | reiserfs_read_lock_xattrs(inode->i_sb); | |
801 | dir = open_xa_dir(inode, FL_READONLY); | |
802 | reiserfs_read_unlock_xattrs(inode->i_sb); | |
803 | if (IS_ERR(dir)) { | |
804 | err = PTR_ERR(dir); | |
805 | goto out; | |
806 | } else if (!dir->d_inode) { | |
807 | dput(dir); | |
808 | return 0; | |
809 | } | |
810 | ||
811 | fp = dentry_open(dir, NULL, O_RDWR); | |
812 | if (IS_ERR(fp)) { | |
813 | err = PTR_ERR(fp); | |
814 | /* dentry_open dputs the dentry if it fails */ | |
815 | goto out; | |
816 | } | |
817 | ||
818 | lock_kernel(); | |
819 | err = xattr_readdir(fp, reiserfs_delete_xattrs_filler, dir); | |
820 | if (err) { | |
821 | unlock_kernel(); | |
822 | goto out_dir; | |
823 | } | |
824 | ||
825 | /* Leftovers besides . and .. -- that's not good. */ | |
826 | if (dir->d_inode->i_nlink <= 2) { | |
827 | root = get_xa_root(inode->i_sb); | |
828 | reiserfs_write_lock_xattrs(inode->i_sb); | |
829 | err = vfs_rmdir(root->d_inode, dir); | |
830 | reiserfs_write_unlock_xattrs(inode->i_sb); | |
831 | dput(root); | |
832 | } else { | |
833 | reiserfs_warning(inode->i_sb, | |
834 | "Couldn't remove all entries in directory"); | |
835 | } | |
836 | unlock_kernel(); | |
837 | ||
838 | out_dir: | |
839 | fput(fp); | |
840 | ||
841 | out: | |
842 | if (!err) | |
843 | REISERFS_I(inode)->i_flags = | |
844 | REISERFS_I(inode)->i_flags & ~i_has_xattr_dir; | |
845 | return err; | |
1da177e4 LT |
846 | } |
847 | ||
848 | struct reiserfs_chown_buf { | |
bd4c625c LT |
849 | struct inode *inode; |
850 | struct dentry *xadir; | |
851 | struct iattr *attrs; | |
1da177e4 LT |
852 | }; |
853 | ||
854 | /* XXX: If there is a better way to do this, I'd love to hear about it */ | |
855 | static int | |
bd4c625c LT |
856 | reiserfs_chown_xattrs_filler(void *buf, const char *name, int namelen, |
857 | loff_t offset, ino_t ino, unsigned int d_type) | |
1da177e4 | 858 | { |
bd4c625c LT |
859 | struct reiserfs_chown_buf *chown_buf = (struct reiserfs_chown_buf *)buf; |
860 | struct dentry *xafile, *xadir = chown_buf->xadir; | |
861 | struct iattr *attrs = chown_buf->attrs; | |
862 | int err = 0; | |
863 | ||
864 | xafile = lookup_one_len(name, xadir, namelen); | |
865 | if (IS_ERR(xafile)) | |
866 | return PTR_ERR(xafile); | |
867 | else if (!xafile->d_inode) { | |
868 | dput(xafile); | |
869 | return -ENODATA; | |
870 | } | |
871 | ||
872 | if (!S_ISDIR(xafile->d_inode->i_mode)) | |
873 | err = notify_change(xafile, attrs); | |
874 | dput(xafile); | |
875 | ||
876 | return err; | |
1da177e4 LT |
877 | } |
878 | ||
bd4c625c | 879 | int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs) |
1da177e4 | 880 | { |
bd4c625c LT |
881 | struct file *fp; |
882 | struct dentry *dir; | |
883 | int err = 0; | |
884 | struct reiserfs_chown_buf buf; | |
885 | unsigned int ia_valid = attrs->ia_valid; | |
886 | ||
887 | /* Skip out, an xattr has no xattrs associated with it */ | |
888 | if (is_reiserfs_priv_object(inode) || | |
889 | get_inode_sd_version(inode) == STAT_DATA_V1 || | |
890 | !reiserfs_xattrs(inode->i_sb)) { | |
891 | return 0; | |
892 | } | |
893 | reiserfs_read_lock_xattrs(inode->i_sb); | |
894 | dir = open_xa_dir(inode, FL_READONLY); | |
895 | reiserfs_read_unlock_xattrs(inode->i_sb); | |
896 | if (IS_ERR(dir)) { | |
897 | if (PTR_ERR(dir) != -ENODATA) | |
898 | err = PTR_ERR(dir); | |
899 | goto out; | |
900 | } else if (!dir->d_inode) { | |
901 | dput(dir); | |
902 | goto out; | |
903 | } | |
904 | ||
905 | fp = dentry_open(dir, NULL, O_RDWR); | |
906 | if (IS_ERR(fp)) { | |
907 | err = PTR_ERR(fp); | |
908 | /* dentry_open dputs the dentry if it fails */ | |
909 | goto out; | |
910 | } | |
1da177e4 | 911 | |
bd4c625c LT |
912 | lock_kernel(); |
913 | ||
914 | attrs->ia_valid &= (ATTR_UID | ATTR_GID | ATTR_CTIME); | |
915 | buf.xadir = dir; | |
916 | buf.attrs = attrs; | |
917 | buf.inode = inode; | |
918 | ||
919 | err = xattr_readdir(fp, reiserfs_chown_xattrs_filler, &buf); | |
920 | if (err) { | |
921 | unlock_kernel(); | |
922 | goto out_dir; | |
923 | } | |
924 | ||
925 | err = notify_change(dir, attrs); | |
926 | unlock_kernel(); | |
927 | ||
928 | out_dir: | |
929 | fput(fp); | |
930 | ||
931 | out: | |
932 | attrs->ia_valid = ia_valid; | |
933 | return err; | |
934 | } | |
1da177e4 LT |
935 | |
936 | /* Actual operations that are exported to VFS-land */ | |
937 | ||
938 | /* | |
939 | * Inode operation getxattr() | |
1b1dcc1b | 940 | * Preliminary locking: we down dentry->d_inode->i_mutex |
1da177e4 LT |
941 | */ |
942 | ssize_t | |
bd4c625c LT |
943 | reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer, |
944 | size_t size) | |
1da177e4 | 945 | { |
bd4c625c LT |
946 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
947 | int err; | |
948 | ||
949 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
950 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
951 | return -EOPNOTSUPP; | |
952 | ||
953 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
954 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
955 | err = xah->get(dentry->d_inode, name, buffer, size); | |
956 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
957 | reiserfs_read_unlock_xattr_i(dentry->d_inode); | |
958 | return err; | |
1da177e4 LT |
959 | } |
960 | ||
1da177e4 LT |
961 | /* |
962 | * Inode operation setxattr() | |
963 | * | |
1b1dcc1b | 964 | * dentry->d_inode->i_mutex down |
1da177e4 LT |
965 | */ |
966 | int | |
bd4c625c LT |
967 | reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
968 | size_t size, int flags) | |
1da177e4 | 969 | { |
bd4c625c LT |
970 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); |
971 | int err; | |
972 | int lock; | |
973 | ||
974 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || | |
975 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
976 | return -EOPNOTSUPP; | |
977 | ||
bd4c625c LT |
978 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
979 | lock = !has_xattr_dir(dentry->d_inode); | |
980 | if (lock) | |
981 | reiserfs_write_lock_xattrs(dentry->d_sb); | |
982 | else | |
983 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
984 | err = xah->set(dentry->d_inode, name, value, size, flags); | |
985 | if (lock) | |
986 | reiserfs_write_unlock_xattrs(dentry->d_sb); | |
987 | else | |
988 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
989 | reiserfs_write_unlock_xattr_i(dentry->d_inode); | |
990 | return err; | |
1da177e4 LT |
991 | } |
992 | ||
993 | /* | |
994 | * Inode operation removexattr() | |
995 | * | |
1b1dcc1b | 996 | * dentry->d_inode->i_mutex down |
1da177e4 | 997 | */ |
bd4c625c | 998 | int reiserfs_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 999 | { |
bd4c625c LT |
1000 | int err; |
1001 | struct reiserfs_xattr_handler *xah = find_xattr_handler_prefix(name); | |
1da177e4 | 1002 | |
bd4c625c LT |
1003 | if (!xah || !reiserfs_xattrs(dentry->d_sb) || |
1004 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
1005 | return -EOPNOTSUPP; | |
1da177e4 | 1006 | |
bd4c625c LT |
1007 | reiserfs_write_lock_xattr_i(dentry->d_inode); |
1008 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
1da177e4 | 1009 | |
bd4c625c LT |
1010 | /* Deletion pre-operation */ |
1011 | if (xah->del) { | |
1012 | err = xah->del(dentry->d_inode, name); | |
1013 | if (err) | |
1014 | goto out; | |
1015 | } | |
1da177e4 | 1016 | |
bd4c625c | 1017 | err = reiserfs_xattr_del(dentry->d_inode, name); |
1da177e4 | 1018 | |
bd4c625c LT |
1019 | dentry->d_inode->i_ctime = CURRENT_TIME_SEC; |
1020 | mark_inode_dirty(dentry->d_inode); | |
1da177e4 | 1021 | |
bd4c625c LT |
1022 | out: |
1023 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
1024 | reiserfs_write_unlock_xattr_i(dentry->d_inode); | |
1025 | return err; | |
1da177e4 LT |
1026 | } |
1027 | ||
1da177e4 LT |
1028 | /* This is what filldir will use: |
1029 | * r_pos will always contain the amount of space required for the entire | |
1030 | * list. If r_pos becomes larger than r_size, we need more space and we | |
1031 | * return an error indicating this. If r_pos is less than r_size, then we've | |
1032 | * filled the buffer successfully and we return success */ | |
1033 | struct reiserfs_listxattr_buf { | |
bd4c625c LT |
1034 | int r_pos; |
1035 | int r_size; | |
1036 | char *r_buf; | |
1037 | struct inode *r_inode; | |
1da177e4 LT |
1038 | }; |
1039 | ||
1040 | static int | |
bd4c625c LT |
1041 | reiserfs_listxattr_filler(void *buf, const char *name, int namelen, |
1042 | loff_t offset, ino_t ino, unsigned int d_type) | |
1da177e4 | 1043 | { |
bd4c625c LT |
1044 | struct reiserfs_listxattr_buf *b = (struct reiserfs_listxattr_buf *)buf; |
1045 | int len = 0; | |
1046 | if (name[0] != '.' | |
1047 | || (namelen != 1 && (name[1] != '.' || namelen != 2))) { | |
1048 | struct reiserfs_xattr_handler *xah = | |
1049 | find_xattr_handler_prefix(name); | |
1050 | if (!xah) | |
1051 | return 0; /* Unsupported xattr name, skip it */ | |
1052 | ||
1053 | /* We call ->list() twice because the operation isn't required to just | |
1054 | * return the name back - we want to make sure we have enough space */ | |
1055 | len += xah->list(b->r_inode, name, namelen, NULL); | |
1056 | ||
1057 | if (len) { | |
1058 | if (b->r_pos + len + 1 <= b->r_size) { | |
1059 | char *p = b->r_buf + b->r_pos; | |
1060 | p += xah->list(b->r_inode, name, namelen, p); | |
1061 | *p++ = '\0'; | |
1062 | } | |
1063 | b->r_pos += len + 1; | |
1064 | } | |
1065 | } | |
1066 | ||
1067 | return 0; | |
1da177e4 | 1068 | } |
bd4c625c | 1069 | |
1da177e4 LT |
1070 | /* |
1071 | * Inode operation listxattr() | |
1072 | * | |
1b1dcc1b | 1073 | * Preliminary locking: we down dentry->d_inode->i_mutex |
1da177e4 | 1074 | */ |
bd4c625c | 1075 | ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size) |
1da177e4 | 1076 | { |
bd4c625c LT |
1077 | struct file *fp; |
1078 | struct dentry *dir; | |
1079 | int err = 0; | |
1080 | struct reiserfs_listxattr_buf buf; | |
1081 | ||
1082 | if (!dentry->d_inode) | |
1083 | return -EINVAL; | |
1084 | ||
1085 | if (!reiserfs_xattrs(dentry->d_sb) || | |
1086 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) | |
1087 | return -EOPNOTSUPP; | |
1088 | ||
1089 | reiserfs_read_lock_xattr_i(dentry->d_inode); | |
1090 | reiserfs_read_lock_xattrs(dentry->d_sb); | |
1091 | dir = open_xa_dir(dentry->d_inode, FL_READONLY); | |
1092 | reiserfs_read_unlock_xattrs(dentry->d_sb); | |
1093 | if (IS_ERR(dir)) { | |
1094 | err = PTR_ERR(dir); | |
1095 | if (err == -ENODATA) | |
1096 | err = 0; /* Not an error if there aren't any xattrs */ | |
1097 | goto out; | |
1098 | } | |
1099 | ||
1100 | fp = dentry_open(dir, NULL, O_RDWR); | |
1101 | if (IS_ERR(fp)) { | |
1102 | err = PTR_ERR(fp); | |
1103 | /* dentry_open dputs the dentry if it fails */ | |
1104 | goto out; | |
1105 | } | |
1106 | ||
1107 | buf.r_buf = buffer; | |
1108 | buf.r_size = buffer ? size : 0; | |
1109 | buf.r_pos = 0; | |
1110 | buf.r_inode = dentry->d_inode; | |
1111 | ||
1112 | REISERFS_I(dentry->d_inode)->i_flags |= i_has_xattr_dir; | |
1113 | ||
1114 | err = xattr_readdir(fp, reiserfs_listxattr_filler, &buf); | |
1115 | if (err) | |
1116 | goto out_dir; | |
1117 | ||
1118 | if (buf.r_pos > buf.r_size && buffer != NULL) | |
1119 | err = -ERANGE; | |
1120 | else | |
1121 | err = buf.r_pos; | |
1122 | ||
1123 | out_dir: | |
1124 | fput(fp); | |
1125 | ||
1126 | out: | |
1127 | reiserfs_read_unlock_xattr_i(dentry->d_inode); | |
1128 | return err; | |
1da177e4 LT |
1129 | } |
1130 | ||
1131 | /* This is the implementation for the xattr plugin infrastructure */ | |
bd4c625c | 1132 | static struct list_head xattr_handlers = LIST_HEAD_INIT(xattr_handlers); |
1da177e4 LT |
1133 | static DEFINE_RWLOCK(handler_lock); |
1134 | ||
bd4c625c LT |
1135 | static struct reiserfs_xattr_handler *find_xattr_handler_prefix(const char |
1136 | *prefix) | |
1da177e4 | 1137 | { |
bd4c625c LT |
1138 | struct reiserfs_xattr_handler *xah = NULL; |
1139 | struct list_head *p; | |
1140 | ||
1141 | read_lock(&handler_lock); | |
1142 | list_for_each(p, &xattr_handlers) { | |
1143 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1144 | if (strncmp(xah->prefix, prefix, strlen(xah->prefix)) == 0) | |
1145 | break; | |
1146 | xah = NULL; | |
1147 | } | |
1148 | ||
1149 | read_unlock(&handler_lock); | |
1150 | return xah; | |
1da177e4 LT |
1151 | } |
1152 | ||
bd4c625c | 1153 | static void __unregister_handlers(void) |
1da177e4 | 1154 | { |
bd4c625c LT |
1155 | struct reiserfs_xattr_handler *xah; |
1156 | struct list_head *p, *tmp; | |
1da177e4 | 1157 | |
bd4c625c LT |
1158 | list_for_each_safe(p, tmp, &xattr_handlers) { |
1159 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1160 | if (xah->exit) | |
1161 | xah->exit(); | |
1da177e4 | 1162 | |
bd4c625c LT |
1163 | list_del_init(p); |
1164 | } | |
1165 | INIT_LIST_HEAD(&xattr_handlers); | |
1da177e4 LT |
1166 | } |
1167 | ||
bd4c625c | 1168 | int __init reiserfs_xattr_register_handlers(void) |
1da177e4 | 1169 | { |
bd4c625c LT |
1170 | int err = 0; |
1171 | struct reiserfs_xattr_handler *xah; | |
1172 | struct list_head *p; | |
1da177e4 | 1173 | |
bd4c625c | 1174 | write_lock(&handler_lock); |
1da177e4 | 1175 | |
bd4c625c LT |
1176 | /* If we're already initialized, nothing to do */ |
1177 | if (!list_empty(&xattr_handlers)) { | |
1178 | write_unlock(&handler_lock); | |
1179 | return 0; | |
1180 | } | |
1da177e4 | 1181 | |
bd4c625c LT |
1182 | /* Add the handlers */ |
1183 | list_add_tail(&user_handler.handlers, &xattr_handlers); | |
1184 | list_add_tail(&trusted_handler.handlers, &xattr_handlers); | |
1da177e4 | 1185 | #ifdef CONFIG_REISERFS_FS_SECURITY |
bd4c625c | 1186 | list_add_tail(&security_handler.handlers, &xattr_handlers); |
1da177e4 LT |
1187 | #endif |
1188 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL | |
bd4c625c LT |
1189 | list_add_tail(&posix_acl_access_handler.handlers, &xattr_handlers); |
1190 | list_add_tail(&posix_acl_default_handler.handlers, &xattr_handlers); | |
1da177e4 LT |
1191 | #endif |
1192 | ||
bd4c625c LT |
1193 | /* Run initializers, if available */ |
1194 | list_for_each(p, &xattr_handlers) { | |
1195 | xah = list_entry(p, struct reiserfs_xattr_handler, handlers); | |
1196 | if (xah->init) { | |
1197 | err = xah->init(); | |
1198 | if (err) { | |
1199 | list_del_init(p); | |
1200 | break; | |
1201 | } | |
1202 | } | |
1203 | } | |
1204 | ||
1205 | /* Clean up other handlers, if any failed */ | |
1206 | if (err) | |
1207 | __unregister_handlers(); | |
1208 | ||
1209 | write_unlock(&handler_lock); | |
1210 | return err; | |
1da177e4 LT |
1211 | } |
1212 | ||
bd4c625c | 1213 | void reiserfs_xattr_unregister_handlers(void) |
1da177e4 | 1214 | { |
bd4c625c LT |
1215 | write_lock(&handler_lock); |
1216 | __unregister_handlers(); | |
1217 | write_unlock(&handler_lock); | |
1da177e4 LT |
1218 | } |
1219 | ||
1220 | /* This will catch lookups from the fs root to .reiserfs_priv */ | |
1221 | static int | |
bd4c625c | 1222 | xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name) |
1da177e4 | 1223 | { |
bd4c625c LT |
1224 | struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root; |
1225 | if (name->len == priv_root->d_name.len && | |
1226 | name->hash == priv_root->d_name.hash && | |
1227 | !memcmp(name->name, priv_root->d_name.name, name->len)) { | |
1228 | return -ENOENT; | |
1229 | } else if (q1->len == name->len && | |
1230 | !memcmp(q1->name, name->name, name->len)) | |
1231 | return 0; | |
1232 | return 1; | |
1da177e4 LT |
1233 | } |
1234 | ||
1235 | static struct dentry_operations xattr_lookup_poison_ops = { | |
bd4c625c | 1236 | .d_compare = xattr_lookup_poison, |
1da177e4 LT |
1237 | }; |
1238 | ||
1da177e4 LT |
1239 | /* We need to take a copy of the mount flags since things like |
1240 | * MS_RDONLY don't get set until *after* we're called. | |
1241 | * mount_flags != mount_options */ | |
bd4c625c | 1242 | int reiserfs_xattr_init(struct super_block *s, int mount_flags) |
1da177e4 | 1243 | { |
bd4c625c LT |
1244 | int err = 0; |
1245 | ||
1246 | /* We need generation numbers to ensure that the oid mapping is correct | |
1247 | * v3.5 filesystems don't have them. */ | |
1248 | if (!old_format_only(s)) { | |
1249 | set_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1250 | } else if (reiserfs_xattrs_optional(s)) { | |
1251 | /* Old format filesystem, but optional xattrs have been enabled | |
1252 | * at mount time. Error out. */ | |
1253 | reiserfs_warning(s, "xattrs/ACLs not supported on pre v3.6 " | |
1254 | "format filesystem. Failing mount."); | |
1255 | err = -EOPNOTSUPP; | |
1256 | goto error; | |
1257 | } else { | |
1258 | /* Old format filesystem, but no optional xattrs have been enabled. This | |
1259 | * means we silently disable xattrs on the filesystem. */ | |
1260 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1261 | } | |
1262 | ||
1263 | /* If we don't have the privroot located yet - go find it */ | |
1264 | if (reiserfs_xattrs(s) && !REISERFS_SB(s)->priv_root) { | |
1265 | struct dentry *dentry; | |
1266 | dentry = lookup_one_len(PRIVROOT_NAME, s->s_root, | |
1267 | strlen(PRIVROOT_NAME)); | |
1268 | if (!IS_ERR(dentry)) { | |
1269 | if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) { | |
1270 | struct inode *inode = dentry->d_parent->d_inode; | |
1b1dcc1b | 1271 | mutex_lock(&inode->i_mutex); |
bd4c625c | 1272 | err = inode->i_op->mkdir(inode, dentry, 0700); |
1b1dcc1b | 1273 | mutex_unlock(&inode->i_mutex); |
bd4c625c LT |
1274 | if (err) { |
1275 | dput(dentry); | |
1276 | dentry = NULL; | |
1277 | } | |
1278 | ||
1279 | if (dentry && dentry->d_inode) | |
1280 | reiserfs_warning(s, | |
1281 | "Created %s on %s - reserved for " | |
1282 | "xattr storage.", | |
1283 | PRIVROOT_NAME, | |
1284 | reiserfs_bdevname | |
1285 | (inode->i_sb)); | |
1286 | } else if (!dentry->d_inode) { | |
1287 | dput(dentry); | |
1288 | dentry = NULL; | |
1289 | } | |
1290 | } else | |
1291 | err = PTR_ERR(dentry); | |
1292 | ||
1293 | if (!err && dentry) { | |
1294 | s->s_root->d_op = &xattr_lookup_poison_ops; | |
1295 | reiserfs_mark_inode_private(dentry->d_inode); | |
1296 | REISERFS_SB(s)->priv_root = dentry; | |
1297 | } else if (!(mount_flags & MS_RDONLY)) { /* xattrs are unavailable */ | |
1298 | /* If we're read-only it just means that the dir hasn't been | |
1299 | * created. Not an error -- just no xattrs on the fs. We'll | |
1300 | * check again if we go read-write */ | |
1301 | reiserfs_warning(s, "xattrs/ACLs enabled and couldn't " | |
1302 | "find/create .reiserfs_priv. Failing mount."); | |
1303 | err = -EOPNOTSUPP; | |
1304 | } | |
1305 | } | |
1306 | ||
1307 | error: | |
1308 | /* This is only nonzero if there was an error initializing the xattr | |
1309 | * directory or if there is a condition where we don't support them. */ | |
1310 | if (err) { | |
1311 | clear_bit(REISERFS_XATTRS, &(REISERFS_SB(s)->s_mount_opt)); | |
1312 | clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt)); | |
1313 | clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt)); | |
1314 | } | |
1315 | ||
1316 | /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */ | |
1317 | s->s_flags = s->s_flags & ~MS_POSIXACL; | |
1318 | if (reiserfs_posixacl(s)) | |
1319 | s->s_flags |= MS_POSIXACL; | |
1320 | ||
1321 | return err; | |
1da177e4 LT |
1322 | } |
1323 | ||
1324 | static int | |
bd4c625c LT |
1325 | __reiserfs_permission(struct inode *inode, int mask, struct nameidata *nd, |
1326 | int need_lock) | |
1da177e4 | 1327 | { |
bd4c625c | 1328 | umode_t mode = inode->i_mode; |
1da177e4 LT |
1329 | |
1330 | if (mask & MAY_WRITE) { | |
1331 | /* | |
1332 | * Nobody gets write access to a read-only fs. | |
1333 | */ | |
1334 | if (IS_RDONLY(inode) && | |
1335 | (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) | |
1336 | return -EROFS; | |
1337 | ||
1338 | /* | |
1339 | * Nobody gets write access to an immutable file. | |
1340 | */ | |
1341 | if (IS_IMMUTABLE(inode)) | |
1342 | return -EACCES; | |
1343 | } | |
1344 | ||
1345 | /* We don't do permission checks on the internal objects. | |
bd4c625c LT |
1346 | * Permissions are determined by the "owning" object. */ |
1347 | if (is_reiserfs_priv_object(inode)) | |
1da177e4 LT |
1348 | return 0; |
1349 | ||
1350 | if (current->fsuid == inode->i_uid) { | |
1351 | mode >>= 6; | |
1352 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL | |
1353 | } else if (reiserfs_posixacl(inode->i_sb) && | |
bd4c625c LT |
1354 | get_inode_sd_version(inode) != STAT_DATA_V1) { |
1355 | struct posix_acl *acl; | |
1da177e4 LT |
1356 | |
1357 | /* ACL can't contain additional permissions if | |
1358 | the ACL_MASK entry is 0 */ | |
1359 | if (!(mode & S_IRWXG)) | |
1360 | goto check_groups; | |
1361 | ||
bd4c625c LT |
1362 | if (need_lock) { |
1363 | reiserfs_read_lock_xattr_i(inode); | |
1364 | reiserfs_read_lock_xattrs(inode->i_sb); | |
1365 | } | |
1366 | acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS); | |
1367 | if (need_lock) { | |
1368 | reiserfs_read_unlock_xattrs(inode->i_sb); | |
1369 | reiserfs_read_unlock_xattr_i(inode); | |
1da177e4 | 1370 | } |
bd4c625c LT |
1371 | if (IS_ERR(acl)) { |
1372 | if (PTR_ERR(acl) == -ENODATA) | |
1373 | goto check_groups; | |
1374 | return PTR_ERR(acl); | |
1da177e4 | 1375 | } |
bd4c625c LT |
1376 | |
1377 | if (acl) { | |
1378 | int err = posix_acl_permission(inode, acl, mask); | |
1379 | posix_acl_release(acl); | |
1380 | if (err == -EACCES) { | |
1381 | goto check_capabilities; | |
1382 | } | |
1383 | return err; | |
1da177e4 LT |
1384 | } else { |
1385 | goto check_groups; | |
bd4c625c | 1386 | } |
1da177e4 LT |
1387 | #endif |
1388 | } else { | |
bd4c625c | 1389 | check_groups: |
1da177e4 LT |
1390 | if (in_group_p(inode->i_gid)) |
1391 | mode >>= 3; | |
1392 | } | |
1393 | ||
1394 | /* | |
1395 | * If the DACs are ok we don't need any capability check. | |
1396 | */ | |
bd4c625c | 1397 | if (((mode & mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == mask)) |
1da177e4 LT |
1398 | return 0; |
1399 | ||
bd4c625c | 1400 | check_capabilities: |
1da177e4 LT |
1401 | /* |
1402 | * Read/write DACs are always overridable. | |
1403 | * Executable DACs are overridable if at least one exec bit is set. | |
1404 | */ | |
1405 | if (!(mask & MAY_EXEC) || | |
1406 | (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode)) | |
1407 | if (capable(CAP_DAC_OVERRIDE)) | |
1408 | return 0; | |
1409 | ||
1410 | /* | |
1411 | * Searching includes executable on directories, else just read. | |
1412 | */ | |
1413 | if (mask == MAY_READ || (S_ISDIR(inode->i_mode) && !(mask & MAY_WRITE))) | |
1414 | if (capable(CAP_DAC_READ_SEARCH)) | |
1415 | return 0; | |
1416 | ||
1417 | return -EACCES; | |
1418 | } | |
1419 | ||
bd4c625c | 1420 | int reiserfs_permission(struct inode *inode, int mask, struct nameidata *nd) |
1da177e4 | 1421 | { |
bd4c625c | 1422 | return __reiserfs_permission(inode, mask, nd, 1); |
1da177e4 LT |
1423 | } |
1424 | ||
1425 | int | |
bd4c625c | 1426 | reiserfs_permission_locked(struct inode *inode, int mask, struct nameidata *nd) |
1da177e4 | 1427 | { |
bd4c625c | 1428 | return __reiserfs_permission(inode, mask, nd, 0); |
1da177e4 | 1429 | } |