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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/reiserfs/xattr.c | |
3 | * | |
4 | * Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com> | |
5 | * | |
6 | */ | |
7 | ||
8 | /* | |
9 | * In order to implement EA/ACLs in a clean, backwards compatible manner, | |
10 | * they are implemented as files in a "private" directory. | |
11 | * Each EA is in it's own file, with the directory layout like so (/ is assumed | |
12 | * to be relative to fs root). Inside the /.reiserfs_priv/xattrs directory, | |
13 | * directories named using the capital-hex form of the objectid and | |
14 | * generation number are used. Inside each directory are individual files | |
15 | * named with the name of the extended attribute. | |
16 | * | |
17 | * So, for objectid 12648430, we could have: | |
18 | * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_access | |
19 | * /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_default | |
20 | * /.reiserfs_priv/xattrs/C0FFEE.0/user.Content-Type | |
21 | * .. or similar. | |
22 | * | |
23 | * The file contents are the text of the EA. The size is known based on the | |
24 | * stat data describing the file. | |
25 | * | |
26 | * In the case of system.posix_acl_access and system.posix_acl_default, since | |
27 | * these are special cases for filesystem ACLs, they are interpreted by the | |
28 | * kernel, in addition, they are negatively and positively cached and attached | |
29 | * to the inode so that unnecessary lookups are avoided. | |
d984561b JM |
30 | * |
31 | * Locking works like so: | |
8b6dd72a JM |
32 | * Directory components (xattr root, xattr dir) are protectd by their i_mutex. |
33 | * The xattrs themselves are protected by the xattr_sem. | |
1da177e4 LT |
34 | */ |
35 | ||
36 | #include <linux/reiserfs_fs.h> | |
16f7e0fe | 37 | #include <linux/capability.h> |
1da177e4 LT |
38 | #include <linux/dcache.h> |
39 | #include <linux/namei.h> | |
40 | #include <linux/errno.h> | |
41 | #include <linux/fs.h> | |
42 | #include <linux/file.h> | |
43 | #include <linux/pagemap.h> | |
44 | #include <linux/xattr.h> | |
45 | #include <linux/reiserfs_xattr.h> | |
46 | #include <linux/reiserfs_acl.h> | |
1da177e4 | 47 | #include <asm/uaccess.h> |
3277c39f | 48 | #include <net/checksum.h> |
1da177e4 | 49 | #include <linux/stat.h> |
6c17675e | 50 | #include <linux/quotaops.h> |
1da177e4 | 51 | |
1da177e4 LT |
52 | #define PRIVROOT_NAME ".reiserfs_priv" |
53 | #define XAROOT_NAME "xattrs" | |
54 | ||
1da177e4 | 55 | |
6c17675e JM |
56 | /* Helpers for inode ops. We do this so that we don't have all the VFS |
57 | * overhead and also for proper i_mutex annotation. | |
58 | * dir->i_mutex must be held for all of them. */ | |
3a355cc6 | 59 | #ifdef CONFIG_REISERFS_FS_XATTR |
6c17675e | 60 | static int xattr_create(struct inode *dir, struct dentry *dentry, int mode) |
1da177e4 | 61 | { |
6c17675e | 62 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); |
e1c50248 | 63 | vfs_dq_init(dir); |
6c17675e JM |
64 | return dir->i_op->create(dir, dentry, mode, NULL); |
65 | } | |
3a355cc6 | 66 | #endif |
bd4c625c | 67 | |
6c17675e JM |
68 | static int xattr_mkdir(struct inode *dir, struct dentry *dentry, int mode) |
69 | { | |
70 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
e1c50248 | 71 | vfs_dq_init(dir); |
6c17675e JM |
72 | return dir->i_op->mkdir(dir, dentry, mode); |
73 | } | |
bd4c625c | 74 | |
6c17675e JM |
75 | /* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr |
76 | * mutation ops aren't called during rename or splace, which are the | |
77 | * only other users of I_MUTEX_CHILD. It violates the ordering, but that's | |
78 | * better than allocating another subclass just for this code. */ | |
79 | static int xattr_unlink(struct inode *dir, struct dentry *dentry) | |
80 | { | |
81 | int error; | |
82 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
e1c50248 | 83 | vfs_dq_init(dir); |
bd4c625c | 84 | |
4dd85969 FW |
85 | reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex, |
86 | I_MUTEX_CHILD, dir->i_sb); | |
6c17675e JM |
87 | error = dir->i_op->unlink(dir, dentry); |
88 | mutex_unlock(&dentry->d_inode->i_mutex); | |
89 | ||
90 | if (!error) | |
91 | d_delete(dentry); | |
92 | return error; | |
93 | } | |
94 | ||
95 | static int xattr_rmdir(struct inode *dir, struct dentry *dentry) | |
96 | { | |
97 | int error; | |
98 | BUG_ON(!mutex_is_locked(&dir->i_mutex)); | |
e1c50248 | 99 | vfs_dq_init(dir); |
6c17675e | 100 | |
835d5247 FW |
101 | reiserfs_mutex_lock_nested_safe(&dentry->d_inode->i_mutex, |
102 | I_MUTEX_CHILD, dir->i_sb); | |
6c17675e JM |
103 | dentry_unhash(dentry); |
104 | error = dir->i_op->rmdir(dir, dentry); | |
105 | if (!error) | |
106 | dentry->d_inode->i_flags |= S_DEAD; | |
107 | mutex_unlock(&dentry->d_inode->i_mutex); | |
108 | if (!error) | |
109 | d_delete(dentry); | |
110 | dput(dentry); | |
111 | ||
112 | return error; | |
113 | } | |
114 | ||
6c17675e JM |
115 | #define xattr_may_create(flags) (!flags || flags & XATTR_CREATE) |
116 | ||
ab17c4f0 | 117 | static struct dentry *open_xa_root(struct super_block *sb, int flags) |
6c17675e | 118 | { |
ab17c4f0 JM |
119 | struct dentry *privroot = REISERFS_SB(sb)->priv_root; |
120 | struct dentry *xaroot; | |
121 | if (!privroot->d_inode) | |
122 | return ERR_PTR(-ENODATA); | |
6c17675e | 123 | |
ab17c4f0 | 124 | mutex_lock_nested(&privroot->d_inode->i_mutex, I_MUTEX_XATTR); |
6c17675e | 125 | |
ab17c4f0 | 126 | xaroot = dget(REISERFS_SB(sb)->xattr_root); |
ceb5edc4 JM |
127 | if (!xaroot) |
128 | xaroot = ERR_PTR(-ENODATA); | |
129 | else if (!xaroot->d_inode) { | |
ab17c4f0 | 130 | int err = -ENODATA; |
5a6059c3 | 131 | if (xattr_may_create(flags)) |
ab17c4f0 | 132 | err = xattr_mkdir(privroot->d_inode, xaroot, 0700); |
9b7f3755 | 133 | if (err) { |
ab17c4f0 JM |
134 | dput(xaroot); |
135 | xaroot = ERR_PTR(err); | |
9b7f3755 | 136 | } |
bd4c625c | 137 | } |
6c17675e | 138 | |
ab17c4f0 JM |
139 | mutex_unlock(&privroot->d_inode->i_mutex); |
140 | return xaroot; | |
1da177e4 LT |
141 | } |
142 | ||
bd4c625c | 143 | static struct dentry *open_xa_dir(const struct inode *inode, int flags) |
1da177e4 | 144 | { |
bd4c625c LT |
145 | struct dentry *xaroot, *xadir; |
146 | char namebuf[17]; | |
147 | ||
6c17675e | 148 | xaroot = open_xa_root(inode->i_sb, flags); |
9b7f3755 | 149 | if (IS_ERR(xaroot)) |
bd4c625c | 150 | return xaroot; |
bd4c625c | 151 | |
bd4c625c LT |
152 | snprintf(namebuf, sizeof(namebuf), "%X.%X", |
153 | le32_to_cpu(INODE_PKEY(inode)->k_objectid), | |
154 | inode->i_generation); | |
bd4c625c | 155 | |
ab17c4f0 JM |
156 | mutex_lock_nested(&xaroot->d_inode->i_mutex, I_MUTEX_XATTR); |
157 | ||
158 | xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf)); | |
159 | if (!IS_ERR(xadir) && !xadir->d_inode) { | |
160 | int err = -ENODATA; | |
161 | if (xattr_may_create(flags)) | |
162 | err = xattr_mkdir(xaroot->d_inode, xadir, 0700); | |
163 | if (err) { | |
164 | dput(xadir); | |
165 | xadir = ERR_PTR(err); | |
166 | } | |
167 | } | |
168 | ||
169 | mutex_unlock(&xaroot->d_inode->i_mutex); | |
bd4c625c LT |
170 | dput(xaroot); |
171 | return xadir; | |
1da177e4 LT |
172 | } |
173 | ||
48b32a35 JM |
174 | /* The following are side effects of other operations that aren't explicitly |
175 | * modifying extended attributes. This includes operations such as permissions | |
176 | * or ownership changes, object deletions, etc. */ | |
a41f1a47 JM |
177 | struct reiserfs_dentry_buf { |
178 | struct dentry *xadir; | |
179 | int count; | |
180 | struct dentry *dentries[8]; | |
181 | }; | |
bd4c625c | 182 | |
a72bdb1c | 183 | static int |
a41f1a47 JM |
184 | fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset, |
185 | u64 ino, unsigned int d_type) | |
a72bdb1c | 186 | { |
a41f1a47 | 187 | struct reiserfs_dentry_buf *dbuf = buf; |
a72bdb1c | 188 | struct dentry *dentry; |
5a6059c3 | 189 | WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex)); |
bd4c625c | 190 | |
a41f1a47 JM |
191 | if (dbuf->count == ARRAY_SIZE(dbuf->dentries)) |
192 | return -ENOSPC; | |
bd4c625c | 193 | |
a41f1a47 JM |
194 | if (name[0] == '.' && (name[1] == '\0' || |
195 | (name[1] == '.' && name[2] == '\0'))) | |
196 | return 0; | |
bd4c625c | 197 | |
a41f1a47 | 198 | dentry = lookup_one_len(name, dbuf->xadir, namelen); |
a72bdb1c | 199 | if (IS_ERR(dentry)) { |
a41f1a47 | 200 | return PTR_ERR(dentry); |
a72bdb1c | 201 | } else if (!dentry->d_inode) { |
a41f1a47 JM |
202 | /* A directory entry exists, but no file? */ |
203 | reiserfs_error(dentry->d_sb, "xattr-20003", | |
204 | "Corrupted directory: xattr %s listed but " | |
205 | "not found for file %s.\n", | |
206 | dentry->d_name.name, dbuf->xadir->d_name.name); | |
207 | dput(dentry); | |
208 | return -EIO; | |
bd4c625c | 209 | } |
1da177e4 | 210 | |
a41f1a47 JM |
211 | dbuf->dentries[dbuf->count++] = dentry; |
212 | return 0; | |
1da177e4 LT |
213 | } |
214 | ||
a41f1a47 JM |
215 | static void |
216 | cleanup_dentry_buf(struct reiserfs_dentry_buf *buf) | |
1da177e4 | 217 | { |
a41f1a47 JM |
218 | int i; |
219 | for (i = 0; i < buf->count; i++) | |
220 | if (buf->dentries[i]) | |
221 | dput(buf->dentries[i]); | |
a72bdb1c JM |
222 | } |
223 | ||
a41f1a47 JM |
224 | static int reiserfs_for_each_xattr(struct inode *inode, |
225 | int (*action)(struct dentry *, void *), | |
226 | void *data) | |
a72bdb1c | 227 | { |
a41f1a47 JM |
228 | struct dentry *dir; |
229 | int i, err = 0; | |
230 | loff_t pos = 0; | |
231 | struct reiserfs_dentry_buf buf = { | |
232 | .count = 0, | |
233 | }; | |
1da177e4 | 234 | |
a72bdb1c JM |
235 | /* Skip out, an xattr has no xattrs associated with it */ |
236 | if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1) | |
237 | return 0; | |
1da177e4 | 238 | |
27026a05 | 239 | reiserfs_write_unlock(inode->i_sb); |
6c17675e | 240 | dir = open_xa_dir(inode, XATTR_REPLACE); |
a72bdb1c JM |
241 | if (IS_ERR(dir)) { |
242 | err = PTR_ERR(dir); | |
27026a05 | 243 | reiserfs_write_lock(inode->i_sb); |
a72bdb1c JM |
244 | goto out; |
245 | } else if (!dir->d_inode) { | |
a41f1a47 | 246 | err = 0; |
27026a05 | 247 | reiserfs_write_lock(inode->i_sb); |
a41f1a47 | 248 | goto out_dir; |
a72bdb1c | 249 | } |
1da177e4 | 250 | |
27026a05 FW |
251 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
252 | ||
253 | reiserfs_write_lock(inode->i_sb); | |
254 | ||
a41f1a47 JM |
255 | buf.xadir = dir; |
256 | err = reiserfs_readdir_dentry(dir, &buf, fill_with_dentries, &pos); | |
257 | while ((err == 0 || err == -ENOSPC) && buf.count) { | |
258 | err = 0; | |
1da177e4 | 259 | |
a41f1a47 JM |
260 | for (i = 0; i < buf.count && buf.dentries[i]; i++) { |
261 | int lerr = 0; | |
262 | struct dentry *dentry = buf.dentries[i]; | |
1da177e4 | 263 | |
a41f1a47 JM |
264 | if (err == 0 && !S_ISDIR(dentry->d_inode->i_mode)) |
265 | lerr = action(dentry, data); | |
1da177e4 | 266 | |
a41f1a47 JM |
267 | dput(dentry); |
268 | buf.dentries[i] = NULL; | |
269 | err = lerr ?: err; | |
bd4c625c | 270 | } |
a41f1a47 JM |
271 | buf.count = 0; |
272 | if (!err) | |
273 | err = reiserfs_readdir_dentry(dir, &buf, | |
274 | fill_with_dentries, &pos); | |
8b6dd72a | 275 | } |
a41f1a47 | 276 | mutex_unlock(&dir->d_inode->i_mutex); |
1da177e4 | 277 | |
a41f1a47 JM |
278 | /* Clean up after a failed readdir */ |
279 | cleanup_dentry_buf(&buf); | |
1da177e4 | 280 | |
d984561b | 281 | if (!err) { |
a41f1a47 JM |
282 | /* We start a transaction here to avoid a ABBA situation |
283 | * between the xattr root's i_mutex and the journal lock. | |
284 | * This doesn't incur much additional overhead since the | |
285 | * new transaction will just nest inside the | |
286 | * outer transaction. */ | |
287 | int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 + | |
288 | 4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb); | |
289 | struct reiserfs_transaction_handle th; | |
290 | err = journal_begin(&th, inode->i_sb, blocks); | |
291 | if (!err) { | |
292 | int jerror; | |
8b513f56 FW |
293 | reiserfs_mutex_lock_nested_safe( |
294 | &dir->d_parent->d_inode->i_mutex, | |
295 | I_MUTEX_XATTR, inode->i_sb); | |
a41f1a47 JM |
296 | err = action(dir, data); |
297 | jerror = journal_end(&th, inode->i_sb, blocks); | |
298 | mutex_unlock(&dir->d_parent->d_inode->i_mutex); | |
299 | err = jerror ?: err; | |
300 | } | |
a72bdb1c | 301 | } |
a41f1a47 JM |
302 | out_dir: |
303 | dput(dir); | |
a72bdb1c | 304 | out: |
a41f1a47 JM |
305 | /* -ENODATA isn't an error */ |
306 | if (err == -ENODATA) | |
307 | err = 0; | |
a72bdb1c JM |
308 | return err; |
309 | } | |
1da177e4 | 310 | |
a41f1a47 | 311 | static int delete_one_xattr(struct dentry *dentry, void *data) |
a72bdb1c | 312 | { |
a41f1a47 | 313 | struct inode *dir = dentry->d_parent->d_inode; |
1da177e4 | 314 | |
a41f1a47 JM |
315 | /* This is the xattr dir, handle specially. */ |
316 | if (S_ISDIR(dentry->d_inode->i_mode)) | |
317 | return xattr_rmdir(dir, dentry); | |
1da177e4 | 318 | |
a41f1a47 JM |
319 | return xattr_unlink(dir, dentry); |
320 | } | |
bd4c625c | 321 | |
a41f1a47 JM |
322 | static int chown_one_xattr(struct dentry *dentry, void *data) |
323 | { | |
324 | struct iattr *attrs = data; | |
325 | return reiserfs_setattr(dentry, attrs); | |
326 | } | |
1da177e4 | 327 | |
a41f1a47 JM |
328 | /* No i_mutex, but the inode is unconnected. */ |
329 | int reiserfs_delete_xattrs(struct inode *inode) | |
330 | { | |
331 | int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL); | |
332 | if (err) | |
333 | reiserfs_warning(inode->i_sb, "jdm-20004", | |
334 | "Couldn't delete all xattrs (%d)\n", err); | |
a72bdb1c JM |
335 | return err; |
336 | } | |
1da177e4 | 337 | |
a41f1a47 | 338 | /* inode->i_mutex: down */ |
a72bdb1c JM |
339 | int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs) |
340 | { | |
a41f1a47 | 341 | int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs); |
8b6dd72a JM |
342 | if (err) |
343 | reiserfs_warning(inode->i_sb, "jdm-20007", | |
344 | "Couldn't chown all xattrs (%d)\n", err); | |
a72bdb1c | 345 | return err; |
1da177e4 LT |
346 | } |
347 | ||
a72bdb1c | 348 | #ifdef CONFIG_REISERFS_FS_XATTR |
a72bdb1c JM |
349 | /* Returns a dentry corresponding to a specific extended attribute file |
350 | * for the inode. If flags allow, the file is created. Otherwise, a | |
351 | * valid or negative dentry, or an error is returned. */ | |
48b32a35 JM |
352 | static struct dentry *xattr_lookup(struct inode *inode, const char *name, |
353 | int flags) | |
1da177e4 | 354 | { |
a72bdb1c JM |
355 | struct dentry *xadir, *xafile; |
356 | int err = 0; | |
357 | ||
358 | xadir = open_xa_dir(inode, flags); | |
6c17675e | 359 | if (IS_ERR(xadir)) |
a72bdb1c | 360 | return ERR_CAST(xadir); |
a72bdb1c | 361 | |
5a6059c3 | 362 | mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR); |
a72bdb1c JM |
363 | xafile = lookup_one_len(name, xadir, strlen(name)); |
364 | if (IS_ERR(xafile)) { | |
6c17675e JM |
365 | err = PTR_ERR(xafile); |
366 | goto out; | |
bd4c625c | 367 | } |
a72bdb1c | 368 | |
6c17675e JM |
369 | if (xafile->d_inode && (flags & XATTR_CREATE)) |
370 | err = -EEXIST; | |
a72bdb1c | 371 | |
6c17675e JM |
372 | if (!xafile->d_inode) { |
373 | err = -ENODATA; | |
5a6059c3 | 374 | if (xattr_may_create(flags)) |
6c17675e JM |
375 | err = xattr_create(xadir->d_inode, xafile, |
376 | 0700|S_IFREG); | |
a72bdb1c JM |
377 | } |
378 | ||
6c17675e JM |
379 | if (err) |
380 | dput(xafile); | |
a72bdb1c | 381 | out: |
5a6059c3 | 382 | mutex_unlock(&xadir->d_inode->i_mutex); |
a72bdb1c JM |
383 | dput(xadir); |
384 | if (err) | |
6c17675e | 385 | return ERR_PTR(err); |
a72bdb1c | 386 | return xafile; |
1da177e4 LT |
387 | } |
388 | ||
1da177e4 | 389 | /* Internal operations on file data */ |
bd4c625c | 390 | static inline void reiserfs_put_page(struct page *page) |
1da177e4 | 391 | { |
bd4c625c LT |
392 | kunmap(page); |
393 | page_cache_release(page); | |
1da177e4 LT |
394 | } |
395 | ||
ec6ea56b | 396 | static struct page *reiserfs_get_page(struct inode *dir, size_t n) |
1da177e4 | 397 | { |
bd4c625c LT |
398 | struct address_space *mapping = dir->i_mapping; |
399 | struct page *page; | |
400 | /* We can deadlock if we try to free dentries, | |
401 | and an unlink/rmdir has just occured - GFP_NOFS avoids this */ | |
c4cdd038 | 402 | mapping_set_gfp_mask(mapping, GFP_NOFS); |
ec6ea56b | 403 | page = read_mapping_page(mapping, n >> PAGE_CACHE_SHIFT, NULL); |
bd4c625c | 404 | if (!IS_ERR(page)) { |
bd4c625c | 405 | kmap(page); |
bd4c625c LT |
406 | if (PageError(page)) |
407 | goto fail; | |
408 | } | |
409 | return page; | |
410 | ||
411 | fail: | |
412 | reiserfs_put_page(page); | |
413 | return ERR_PTR(-EIO); | |
1da177e4 LT |
414 | } |
415 | ||
bd4c625c | 416 | static inline __u32 xattr_hash(const char *msg, int len) |
1da177e4 | 417 | { |
bd4c625c | 418 | return csum_partial(msg, len, 0); |
1da177e4 LT |
419 | } |
420 | ||
ba9d8cec VS |
421 | int reiserfs_commit_write(struct file *f, struct page *page, |
422 | unsigned from, unsigned to); | |
423 | int reiserfs_prepare_write(struct file *f, struct page *page, | |
424 | unsigned from, unsigned to); | |
425 | ||
48b32a35 JM |
426 | static void update_ctime(struct inode *inode) |
427 | { | |
428 | struct timespec now = current_fs_time(inode->i_sb); | |
429 | if (hlist_unhashed(&inode->i_hash) || !inode->i_nlink || | |
430 | timespec_equal(&inode->i_ctime, &now)) | |
431 | return; | |
432 | ||
433 | inode->i_ctime = CURRENT_TIME_SEC; | |
434 | mark_inode_dirty(inode); | |
435 | } | |
436 | ||
437 | static int lookup_and_delete_xattr(struct inode *inode, const char *name) | |
438 | { | |
439 | int err = 0; | |
440 | struct dentry *dentry, *xadir; | |
441 | ||
442 | xadir = open_xa_dir(inode, XATTR_REPLACE); | |
443 | if (IS_ERR(xadir)) | |
444 | return PTR_ERR(xadir); | |
445 | ||
5a6059c3 | 446 | mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR); |
48b32a35 JM |
447 | dentry = lookup_one_len(name, xadir, strlen(name)); |
448 | if (IS_ERR(dentry)) { | |
449 | err = PTR_ERR(dentry); | |
450 | goto out_dput; | |
451 | } | |
452 | ||
453 | if (dentry->d_inode) { | |
4f3be1b5 | 454 | reiserfs_write_lock(inode->i_sb); |
48b32a35 | 455 | err = xattr_unlink(xadir->d_inode, dentry); |
4f3be1b5 | 456 | reiserfs_write_unlock(inode->i_sb); |
48b32a35 JM |
457 | update_ctime(inode); |
458 | } | |
459 | ||
460 | dput(dentry); | |
461 | out_dput: | |
5a6059c3 | 462 | mutex_unlock(&xadir->d_inode->i_mutex); |
48b32a35 JM |
463 | dput(xadir); |
464 | return err; | |
465 | } | |
466 | ||
ba9d8cec | 467 | |
1da177e4 LT |
468 | /* Generic extended attribute operations that can be used by xa plugins */ |
469 | ||
470 | /* | |
1b1dcc1b | 471 | * inode->i_mutex: down |
1da177e4 LT |
472 | */ |
473 | int | |
0ab2621e JM |
474 | reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th, |
475 | struct inode *inode, const char *name, | |
476 | const void *buffer, size_t buffer_size, int flags) | |
1da177e4 | 477 | { |
bd4c625c | 478 | int err = 0; |
3227e14c | 479 | struct dentry *dentry; |
bd4c625c LT |
480 | struct page *page; |
481 | char *data; | |
bd4c625c LT |
482 | size_t file_pos = 0; |
483 | size_t buffer_pos = 0; | |
48b32a35 | 484 | size_t new_size; |
bd4c625c LT |
485 | __u32 xahash = 0; |
486 | ||
bd4c625c LT |
487 | if (get_inode_sd_version(inode) == STAT_DATA_V1) |
488 | return -EOPNOTSUPP; | |
489 | ||
3f14fea6 | 490 | reiserfs_write_unlock(inode->i_sb); |
4f3be1b5 FW |
491 | |
492 | if (!buffer) { | |
493 | err = lookup_and_delete_xattr(inode, name); | |
494 | reiserfs_write_lock(inode->i_sb); | |
495 | return err; | |
496 | } | |
497 | ||
48b32a35 | 498 | dentry = xattr_lookup(inode, name, flags); |
3f14fea6 FW |
499 | if (IS_ERR(dentry)) { |
500 | reiserfs_write_lock(inode->i_sb); | |
48b32a35 | 501 | return PTR_ERR(dentry); |
3f14fea6 FW |
502 | } |
503 | ||
f3e22f48 | 504 | down_write(&REISERFS_I(inode)->i_xattr_sem); |
bd4c625c | 505 | |
3f14fea6 | 506 | reiserfs_write_lock(inode->i_sb); |
bd4c625c | 507 | |
8b6dd72a | 508 | xahash = xattr_hash(buffer, buffer_size); |
bd4c625c LT |
509 | while (buffer_pos < buffer_size || buffer_pos == 0) { |
510 | size_t chunk; | |
511 | size_t skip = 0; | |
512 | size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1)); | |
513 | if (buffer_size - buffer_pos > PAGE_CACHE_SIZE) | |
514 | chunk = PAGE_CACHE_SIZE; | |
515 | else | |
516 | chunk = buffer_size - buffer_pos; | |
517 | ||
ec6ea56b | 518 | page = reiserfs_get_page(dentry->d_inode, file_pos); |
bd4c625c LT |
519 | if (IS_ERR(page)) { |
520 | err = PTR_ERR(page); | |
48b32a35 | 521 | goto out_unlock; |
bd4c625c LT |
522 | } |
523 | ||
524 | lock_page(page); | |
525 | data = page_address(page); | |
526 | ||
527 | if (file_pos == 0) { | |
528 | struct reiserfs_xattr_header *rxh; | |
529 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
530 | if (chunk + skip > PAGE_CACHE_SIZE) | |
531 | chunk = PAGE_CACHE_SIZE - skip; | |
532 | rxh = (struct reiserfs_xattr_header *)data; | |
533 | rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC); | |
534 | rxh->h_hash = cpu_to_le32(xahash); | |
535 | } | |
536 | ||
3227e14c | 537 | err = reiserfs_prepare_write(NULL, page, page_offset, |
ba9d8cec | 538 | page_offset + chunk + skip); |
bd4c625c LT |
539 | if (!err) { |
540 | if (buffer) | |
541 | memcpy(data + skip, buffer + buffer_pos, chunk); | |
3227e14c JM |
542 | err = reiserfs_commit_write(NULL, page, page_offset, |
543 | page_offset + chunk + | |
544 | skip); | |
bd4c625c LT |
545 | } |
546 | unlock_page(page); | |
547 | reiserfs_put_page(page); | |
548 | buffer_pos += chunk; | |
549 | file_pos += chunk; | |
550 | skip = 0; | |
551 | if (err || buffer_size == 0 || !buffer) | |
552 | break; | |
553 | } | |
554 | ||
48b32a35 JM |
555 | new_size = buffer_size + sizeof(struct reiserfs_xattr_header); |
556 | if (!err && new_size < i_size_read(dentry->d_inode)) { | |
557 | struct iattr newattrs = { | |
558 | .ia_ctime = current_fs_time(inode->i_sb), | |
559 | .ia_size = buffer_size, | |
560 | .ia_valid = ATTR_SIZE | ATTR_CTIME, | |
561 | }; | |
562 | mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR); | |
563 | down_write(&dentry->d_inode->i_alloc_sem); | |
564 | err = reiserfs_setattr(dentry, &newattrs); | |
565 | up_write(&dentry->d_inode->i_alloc_sem); | |
566 | mutex_unlock(&dentry->d_inode->i_mutex); | |
567 | } else | |
568 | update_ctime(inode); | |
569 | out_unlock: | |
8b6dd72a | 570 | up_write(&REISERFS_I(inode)->i_xattr_sem); |
3227e14c | 571 | dput(dentry); |
48b32a35 JM |
572 | return err; |
573 | } | |
bd4c625c | 574 | |
0ab2621e JM |
575 | /* We need to start a transaction to maintain lock ordering */ |
576 | int reiserfs_xattr_set(struct inode *inode, const char *name, | |
577 | const void *buffer, size_t buffer_size, int flags) | |
48b32a35 | 578 | { |
0ab2621e JM |
579 | |
580 | struct reiserfs_transaction_handle th; | |
581 | int error, error2; | |
582 | size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size); | |
583 | ||
584 | if (!(flags & XATTR_REPLACE)) | |
585 | jbegin_count += reiserfs_xattr_jcreate_nblocks(inode); | |
586 | ||
587 | reiserfs_write_lock(inode->i_sb); | |
588 | error = journal_begin(&th, inode->i_sb, jbegin_count); | |
589 | if (error) { | |
590 | reiserfs_write_unlock(inode->i_sb); | |
591 | return error; | |
1da177e4 | 592 | } |
bd4c625c | 593 | |
0ab2621e JM |
594 | error = reiserfs_xattr_set_handle(&th, inode, name, |
595 | buffer, buffer_size, flags); | |
bd4c625c | 596 | |
0ab2621e JM |
597 | error2 = journal_end(&th, inode->i_sb, jbegin_count); |
598 | if (error == 0) | |
599 | error = error2; | |
600 | reiserfs_write_unlock(inode->i_sb); | |
601 | ||
602 | return error; | |
1da177e4 LT |
603 | } |
604 | ||
605 | /* | |
1b1dcc1b | 606 | * inode->i_mutex: down |
1da177e4 LT |
607 | */ |
608 | int | |
48b32a35 | 609 | reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer, |
bd4c625c | 610 | size_t buffer_size) |
1da177e4 | 611 | { |
bd4c625c | 612 | ssize_t err = 0; |
3227e14c | 613 | struct dentry *dentry; |
bd4c625c LT |
614 | size_t isize; |
615 | size_t file_pos = 0; | |
616 | size_t buffer_pos = 0; | |
617 | struct page *page; | |
bd4c625c LT |
618 | __u32 hash = 0; |
619 | ||
620 | if (name == NULL) | |
621 | return -EINVAL; | |
622 | ||
623 | /* We can't have xattrs attached to v1 items since they don't have | |
624 | * generation numbers */ | |
625 | if (get_inode_sd_version(inode) == STAT_DATA_V1) | |
626 | return -EOPNOTSUPP; | |
627 | ||
48b32a35 | 628 | dentry = xattr_lookup(inode, name, XATTR_REPLACE); |
3227e14c JM |
629 | if (IS_ERR(dentry)) { |
630 | err = PTR_ERR(dentry); | |
bd4c625c LT |
631 | goto out; |
632 | } | |
633 | ||
8b6dd72a | 634 | down_read(&REISERFS_I(inode)->i_xattr_sem); |
d984561b | 635 | |
f437c529 | 636 | isize = i_size_read(dentry->d_inode); |
bd4c625c LT |
637 | |
638 | /* Just return the size needed */ | |
639 | if (buffer == NULL) { | |
640 | err = isize - sizeof(struct reiserfs_xattr_header); | |
8b6dd72a | 641 | goto out_unlock; |
bd4c625c LT |
642 | } |
643 | ||
644 | if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) { | |
645 | err = -ERANGE; | |
8b6dd72a | 646 | goto out_unlock; |
bd4c625c LT |
647 | } |
648 | ||
649 | while (file_pos < isize) { | |
650 | size_t chunk; | |
651 | char *data; | |
652 | size_t skip = 0; | |
653 | if (isize - file_pos > PAGE_CACHE_SIZE) | |
654 | chunk = PAGE_CACHE_SIZE; | |
655 | else | |
656 | chunk = isize - file_pos; | |
657 | ||
a72bdb1c | 658 | page = reiserfs_get_page(dentry->d_inode, file_pos); |
bd4c625c LT |
659 | if (IS_ERR(page)) { |
660 | err = PTR_ERR(page); | |
8b6dd72a | 661 | goto out_unlock; |
bd4c625c LT |
662 | } |
663 | ||
664 | lock_page(page); | |
665 | data = page_address(page); | |
666 | if (file_pos == 0) { | |
667 | struct reiserfs_xattr_header *rxh = | |
668 | (struct reiserfs_xattr_header *)data; | |
669 | skip = file_pos = sizeof(struct reiserfs_xattr_header); | |
670 | chunk -= skip; | |
671 | /* Magic doesn't match up.. */ | |
672 | if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) { | |
673 | unlock_page(page); | |
674 | reiserfs_put_page(page); | |
a72bdb1c | 675 | reiserfs_warning(inode->i_sb, "jdm-20001", |
bd4c625c LT |
676 | "Invalid magic for xattr (%s) " |
677 | "associated with %k", name, | |
678 | INODE_PKEY(inode)); | |
679 | err = -EIO; | |
8b6dd72a | 680 | goto out_unlock; |
bd4c625c LT |
681 | } |
682 | hash = le32_to_cpu(rxh->h_hash); | |
683 | } | |
684 | memcpy(buffer + buffer_pos, data + skip, chunk); | |
685 | unlock_page(page); | |
686 | reiserfs_put_page(page); | |
687 | file_pos += chunk; | |
688 | buffer_pos += chunk; | |
689 | skip = 0; | |
690 | } | |
691 | err = isize - sizeof(struct reiserfs_xattr_header); | |
692 | ||
693 | if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) != | |
694 | hash) { | |
a72bdb1c | 695 | reiserfs_warning(inode->i_sb, "jdm-20002", |
bd4c625c LT |
696 | "Invalid hash for xattr (%s) associated " |
697 | "with %k", name, INODE_PKEY(inode)); | |
698 | err = -EIO; | |
699 | } | |
700 | ||
8b6dd72a JM |
701 | out_unlock: |
702 | up_read(&REISERFS_I(inode)->i_xattr_sem); | |
3227e14c | 703 | dput(dentry); |
bd4c625c | 704 | |
a72bdb1c | 705 | out: |
bd4c625c | 706 | return err; |
1da177e4 LT |
707 | } |
708 | ||
48b32a35 JM |
709 | /* |
710 | * In order to implement different sets of xattr operations for each xattr | |
711 | * prefix with the generic xattr API, a filesystem should create a | |
712 | * null-terminated array of struct xattr_handler (one for each prefix) and | |
713 | * hang a pointer to it off of the s_xattr field of the superblock. | |
714 | * | |
715 | * The generic_fooxattr() functions will use this list to dispatch xattr | |
716 | * operations to the correct xattr_handler. | |
717 | */ | |
718 | #define for_each_xattr_handler(handlers, handler) \ | |
719 | for ((handler) = *(handlers)++; \ | |
720 | (handler) != NULL; \ | |
721 | (handler) = *(handlers)++) | |
1da177e4 | 722 | |
48b32a35 JM |
723 | /* This is the implementation for the xattr plugin infrastructure */ |
724 | static inline struct xattr_handler * | |
725 | find_xattr_handler_prefix(struct xattr_handler **handlers, | |
726 | const char *name) | |
1da177e4 | 727 | { |
48b32a35 | 728 | struct xattr_handler *xah; |
bd4c625c | 729 | |
48b32a35 JM |
730 | if (!handlers) |
731 | return NULL; | |
bd4c625c | 732 | |
48b32a35 JM |
733 | for_each_xattr_handler(handlers, xah) { |
734 | if (strncmp(xah->prefix, name, strlen(xah->prefix)) == 0) | |
735 | break; | |
bd4c625c LT |
736 | } |
737 | ||
48b32a35 | 738 | return xah; |
bd4c625c | 739 | } |
1da177e4 | 740 | |
1da177e4 LT |
741 | |
742 | /* | |
743 | * Inode operation getxattr() | |
1da177e4 LT |
744 | */ |
745 | ssize_t | |
bd4c625c LT |
746 | reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer, |
747 | size_t size) | |
1da177e4 | 748 | { |
48b32a35 JM |
749 | struct inode *inode = dentry->d_inode; |
750 | struct xattr_handler *handler; | |
bd4c625c | 751 | |
48b32a35 JM |
752 | handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name); |
753 | ||
754 | if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1) | |
bd4c625c LT |
755 | return -EOPNOTSUPP; |
756 | ||
48b32a35 | 757 | return handler->get(inode, name, buffer, size); |
1da177e4 LT |
758 | } |
759 | ||
1da177e4 LT |
760 | /* |
761 | * Inode operation setxattr() | |
762 | * | |
1b1dcc1b | 763 | * dentry->d_inode->i_mutex down |
1da177e4 LT |
764 | */ |
765 | int | |
bd4c625c LT |
766 | reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
767 | size_t size, int flags) | |
1da177e4 | 768 | { |
48b32a35 JM |
769 | struct inode *inode = dentry->d_inode; |
770 | struct xattr_handler *handler; | |
bd4c625c | 771 | |
48b32a35 JM |
772 | handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name); |
773 | ||
774 | if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1) | |
bd4c625c LT |
775 | return -EOPNOTSUPP; |
776 | ||
48b32a35 | 777 | return handler->set(inode, name, value, size, flags); |
1da177e4 LT |
778 | } |
779 | ||
780 | /* | |
781 | * Inode operation removexattr() | |
782 | * | |
1b1dcc1b | 783 | * dentry->d_inode->i_mutex down |
1da177e4 | 784 | */ |
bd4c625c | 785 | int reiserfs_removexattr(struct dentry *dentry, const char *name) |
1da177e4 | 786 | { |
48b32a35 JM |
787 | struct inode *inode = dentry->d_inode; |
788 | struct xattr_handler *handler; | |
789 | handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name); | |
1da177e4 | 790 | |
48b32a35 | 791 | if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1) |
bd4c625c | 792 | return -EOPNOTSUPP; |
1da177e4 | 793 | |
48b32a35 | 794 | return handler->set(inode, name, NULL, 0, XATTR_REPLACE); |
1da177e4 LT |
795 | } |
796 | ||
48b32a35 JM |
797 | struct listxattr_buf { |
798 | size_t size; | |
799 | size_t pos; | |
800 | char *buf; | |
801 | struct inode *inode; | |
1da177e4 LT |
802 | }; |
803 | ||
48b32a35 JM |
804 | static int listxattr_filler(void *buf, const char *name, int namelen, |
805 | loff_t offset, u64 ino, unsigned int d_type) | |
1da177e4 | 806 | { |
48b32a35 JM |
807 | struct listxattr_buf *b = (struct listxattr_buf *)buf; |
808 | size_t size; | |
809 | if (name[0] != '.' || | |
810 | (namelen != 1 && (name[1] != '.' || namelen != 2))) { | |
811 | struct xattr_handler *handler; | |
812 | handler = find_xattr_handler_prefix(b->inode->i_sb->s_xattr, | |
813 | name); | |
814 | if (!handler) /* Unsupported xattr name */ | |
815 | return 0; | |
816 | if (b->buf) { | |
817 | size = handler->list(b->inode, b->buf + b->pos, | |
818 | b->size, name, namelen); | |
819 | if (size > b->size) | |
820 | return -ERANGE; | |
821 | } else { | |
822 | size = handler->list(b->inode, NULL, 0, name, namelen); | |
bd4c625c | 823 | } |
bd4c625c | 824 | |
48b32a35 JM |
825 | b->pos += size; |
826 | } | |
bd4c625c | 827 | return 0; |
1da177e4 | 828 | } |
bd4c625c | 829 | |
1da177e4 LT |
830 | /* |
831 | * Inode operation listxattr() | |
832 | * | |
48b32a35 JM |
833 | * We totally ignore the generic listxattr here because it would be stupid |
834 | * not to. Since the xattrs are organized in a directory, we can just | |
835 | * readdir to find them. | |
1da177e4 | 836 | */ |
bd4c625c | 837 | ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size) |
1da177e4 | 838 | { |
bd4c625c LT |
839 | struct dentry *dir; |
840 | int err = 0; | |
a41f1a47 | 841 | loff_t pos = 0; |
48b32a35 JM |
842 | struct listxattr_buf buf = { |
843 | .inode = dentry->d_inode, | |
844 | .buf = buffer, | |
845 | .size = buffer ? size : 0, | |
846 | }; | |
bd4c625c LT |
847 | |
848 | if (!dentry->d_inode) | |
849 | return -EINVAL; | |
850 | ||
677c9b2e | 851 | if (!dentry->d_sb->s_xattr || |
bd4c625c LT |
852 | get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1) |
853 | return -EOPNOTSUPP; | |
854 | ||
6c17675e | 855 | dir = open_xa_dir(dentry->d_inode, XATTR_REPLACE); |
bd4c625c LT |
856 | if (IS_ERR(dir)) { |
857 | err = PTR_ERR(dir); | |
858 | if (err == -ENODATA) | |
48b32a35 | 859 | err = 0; /* Not an error if there aren't any xattrs */ |
bd4c625c LT |
860 | goto out; |
861 | } | |
862 | ||
6c17675e | 863 | mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_XATTR); |
a41f1a47 | 864 | err = reiserfs_readdir_dentry(dir, &buf, listxattr_filler, &pos); |
6c17675e | 865 | mutex_unlock(&dir->d_inode->i_mutex); |
bd4c625c | 866 | |
48b32a35 JM |
867 | if (!err) |
868 | err = buf.pos; | |
bd4c625c | 869 | |
3227e14c | 870 | dput(dir); |
8b6dd72a | 871 | out: |
bd4c625c | 872 | return err; |
1da177e4 LT |
873 | } |
874 | ||
a72bdb1c | 875 | static int reiserfs_check_acl(struct inode *inode, int mask) |
1da177e4 | 876 | { |
a72bdb1c JM |
877 | struct posix_acl *acl; |
878 | int error = -EAGAIN; /* do regular unix permission checks by default */ | |
bd4c625c | 879 | |
a72bdb1c JM |
880 | acl = reiserfs_get_acl(inode, ACL_TYPE_ACCESS); |
881 | ||
a72bdb1c JM |
882 | if (acl) { |
883 | if (!IS_ERR(acl)) { | |
884 | error = posix_acl_permission(inode, acl, mask); | |
885 | posix_acl_release(acl); | |
886 | } else if (PTR_ERR(acl) != -ENODATA) | |
887 | error = PTR_ERR(acl); | |
bd4c625c LT |
888 | } |
889 | ||
a72bdb1c | 890 | return error; |
1da177e4 LT |
891 | } |
892 | ||
a72bdb1c | 893 | static int create_privroot(struct dentry *dentry) |
1da177e4 | 894 | { |
a72bdb1c JM |
895 | int err; |
896 | struct inode *inode = dentry->d_parent->d_inode; | |
5a6059c3 JM |
897 | WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex)); |
898 | ||
6c17675e | 899 | err = xattr_mkdir(inode, dentry, 0700); |
edcc37a0 AV |
900 | if (err || !dentry->d_inode) { |
901 | reiserfs_warning(dentry->d_sb, "jdm-20006", | |
902 | "xattrs/ACLs enabled and couldn't " | |
903 | "find/create .reiserfs_priv. " | |
904 | "Failing mount."); | |
905 | return -EOPNOTSUPP; | |
bd4c625c LT |
906 | } |
907 | ||
edcc37a0 AV |
908 | dentry->d_inode->i_flags |= S_PRIVATE; |
909 | reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr " | |
910 | "storage.\n", PRIVROOT_NAME); | |
bd4c625c | 911 | |
edcc37a0 | 912 | return 0; |
1da177e4 LT |
913 | } |
914 | ||
12abb35a JM |
915 | #else |
916 | int __init reiserfs_xattr_register_handlers(void) { return 0; } | |
917 | void reiserfs_xattr_unregister_handlers(void) {} | |
918 | static int create_privroot(struct dentry *dentry) { return 0; } | |
919 | #endif | |
920 | ||
921 | /* Actual operations that are exported to VFS-land */ | |
922 | struct xattr_handler *reiserfs_xattr_handlers[] = { | |
923 | #ifdef CONFIG_REISERFS_FS_XATTR | |
924 | &reiserfs_xattr_user_handler, | |
925 | &reiserfs_xattr_trusted_handler, | |
926 | #endif | |
927 | #ifdef CONFIG_REISERFS_FS_SECURITY | |
928 | &reiserfs_xattr_security_handler, | |
929 | #endif | |
930 | #ifdef CONFIG_REISERFS_FS_POSIX_ACL | |
931 | &reiserfs_posix_acl_access_handler, | |
932 | &reiserfs_posix_acl_default_handler, | |
933 | #endif | |
934 | NULL | |
935 | }; | |
936 | ||
a72bdb1c | 937 | static int xattr_mount_check(struct super_block *s) |
1da177e4 | 938 | { |
a72bdb1c JM |
939 | /* We need generation numbers to ensure that the oid mapping is correct |
940 | * v3.5 filesystems don't have them. */ | |
48b32a35 JM |
941 | if (old_format_only(s)) { |
942 | if (reiserfs_xattrs_optional(s)) { | |
943 | /* Old format filesystem, but optional xattrs have | |
944 | * been enabled. Error out. */ | |
945 | reiserfs_warning(s, "jdm-2005", | |
946 | "xattrs/ACLs not supported " | |
947 | "on pre-v3.6 format filesystems. " | |
948 | "Failing mount."); | |
949 | return -EOPNOTSUPP; | |
950 | } | |
a72bdb1c JM |
951 | } |
952 | ||
953 | return 0; | |
1da177e4 LT |
954 | } |
955 | ||
b83674c0 JM |
956 | int reiserfs_permission(struct inode *inode, int mask) |
957 | { | |
958 | /* | |
959 | * We don't do permission checks on the internal objects. | |
960 | * Permissions are determined by the "owning" object. | |
961 | */ | |
962 | if (IS_PRIVATE(inode)) | |
963 | return 0; | |
964 | ||
965 | #ifdef CONFIG_REISERFS_FS_XATTR | |
966 | /* | |
967 | * Stat data v1 doesn't support ACLs. | |
968 | */ | |
969 | if (get_inode_sd_version(inode) != STAT_DATA_V1) | |
970 | return generic_permission(inode, mask, reiserfs_check_acl); | |
971 | #endif | |
972 | return generic_permission(inode, mask, NULL); | |
973 | } | |
974 | ||
1da177e4 LT |
975 | /* This will catch lookups from the fs root to .reiserfs_priv */ |
976 | static int | |
bd4c625c | 977 | xattr_lookup_poison(struct dentry *dentry, struct qstr *q1, struct qstr *name) |
1da177e4 | 978 | { |
bd4c625c | 979 | struct dentry *priv_root = REISERFS_SB(dentry->d_sb)->priv_root; |
edcc37a0 | 980 | if (container_of(q1, struct dentry, d_name) == priv_root) |
bd4c625c | 981 | return -ENOENT; |
edcc37a0 | 982 | if (q1->len == name->len && |
bd4c625c LT |
983 | !memcmp(q1->name, name->name, name->len)) |
984 | return 0; | |
985 | return 1; | |
1da177e4 LT |
986 | } |
987 | ||
e16404ed | 988 | static const struct dentry_operations xattr_lookup_poison_ops = { |
bd4c625c | 989 | .d_compare = xattr_lookup_poison, |
1da177e4 LT |
990 | }; |
991 | ||
edcc37a0 AV |
992 | int reiserfs_lookup_privroot(struct super_block *s) |
993 | { | |
994 | struct dentry *dentry; | |
995 | int err = 0; | |
996 | ||
997 | /* If we don't have the privroot located yet - go find it */ | |
c72e0575 | 998 | reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s); |
edcc37a0 AV |
999 | dentry = lookup_one_len(PRIVROOT_NAME, s->s_root, |
1000 | strlen(PRIVROOT_NAME)); | |
1001 | if (!IS_ERR(dentry)) { | |
1002 | REISERFS_SB(s)->priv_root = dentry; | |
73422811 JM |
1003 | if (!reiserfs_expose_privroot(s)) |
1004 | s->s_root->d_op = &xattr_lookup_poison_ops; | |
edcc37a0 AV |
1005 | if (dentry->d_inode) |
1006 | dentry->d_inode->i_flags |= S_PRIVATE; | |
1007 | } else | |
1008 | err = PTR_ERR(dentry); | |
1009 | mutex_unlock(&s->s_root->d_inode->i_mutex); | |
1010 | ||
1011 | return err; | |
1012 | } | |
1013 | ||
1da177e4 LT |
1014 | /* We need to take a copy of the mount flags since things like |
1015 | * MS_RDONLY don't get set until *after* we're called. | |
1016 | * mount_flags != mount_options */ | |
bd4c625c | 1017 | int reiserfs_xattr_init(struct super_block *s, int mount_flags) |
1da177e4 | 1018 | { |
bd4c625c | 1019 | int err = 0; |
ab17c4f0 | 1020 | struct dentry *privroot = REISERFS_SB(s)->priv_root; |
bd4c625c | 1021 | |
a72bdb1c JM |
1022 | err = xattr_mount_check(s); |
1023 | if (err) | |
bd4c625c | 1024 | goto error; |
bd4c625c | 1025 | |
ab17c4f0 | 1026 | if (!privroot->d_inode && !(mount_flags & MS_RDONLY)) { |
ae635c0b | 1027 | reiserfs_mutex_lock_safe(&s->s_root->d_inode->i_mutex, s); |
edcc37a0 | 1028 | err = create_privroot(REISERFS_SB(s)->priv_root); |
5a6059c3 | 1029 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
bd4c625c | 1030 | } |
ab17c4f0 JM |
1031 | |
1032 | if (privroot->d_inode) { | |
48b32a35 | 1033 | s->s_xattr = reiserfs_xattr_handlers; |
c72e0575 | 1034 | reiserfs_mutex_lock_safe(&privroot->d_inode->i_mutex, s); |
ab17c4f0 JM |
1035 | if (!REISERFS_SB(s)->xattr_root) { |
1036 | struct dentry *dentry; | |
1037 | dentry = lookup_one_len(XAROOT_NAME, privroot, | |
1038 | strlen(XAROOT_NAME)); | |
1039 | if (!IS_ERR(dentry)) | |
1040 | REISERFS_SB(s)->xattr_root = dentry; | |
1041 | else | |
1042 | err = PTR_ERR(dentry); | |
1043 | } | |
1044 | mutex_unlock(&privroot->d_inode->i_mutex); | |
1045 | } | |
48b32a35 | 1046 | |
a72bdb1c | 1047 | error: |
bd4c625c | 1048 | if (err) { |
bd4c625c LT |
1049 | clear_bit(REISERFS_XATTRS_USER, &(REISERFS_SB(s)->s_mount_opt)); |
1050 | clear_bit(REISERFS_POSIXACL, &(REISERFS_SB(s)->s_mount_opt)); | |
1051 | } | |
1052 | ||
1053 | /* The super_block MS_POSIXACL must mirror the (no)acl mount option. */ | |
bd4c625c LT |
1054 | if (reiserfs_posixacl(s)) |
1055 | s->s_flags |= MS_POSIXACL; | |
ab17c4f0 | 1056 | else |
ab17c4f0 | 1057 | s->s_flags &= ~MS_POSIXACL; |
bd4c625c LT |
1058 | |
1059 | return err; | |
1da177e4 | 1060 | } |