Merge tag 'sh-for-4.8' of git://git.libc.org/linux-sh
[linux-2.6-block.git] / fs / orangefs / xattr.c
CommitLineData
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1/*
2 * (C) 2001 Clemson University and The University of Chicago
3 *
4 * See COPYING in top-level directory.
5 */
6
7/*
8 * Linux VFS extended attribute operations.
9 */
10
11#include "protocol.h"
575e9461
MM
12#include "orangefs-kernel.h"
13#include "orangefs-bufmap.h"
1182fca3
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14#include <linux/posix_acl_xattr.h>
15#include <linux/xattr.h>
16
17
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YL
18#define SYSTEM_ORANGEFS_KEY "system.pvfs2."
19#define SYSTEM_ORANGEFS_KEY_LEN 13
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20
21/*
22 * this function returns
23 * 0 if the key corresponding to name is not meant to be printed as part
24 * of a listxattr.
25 * 1 if the key corresponding to name is meant to be returned as part of
26 * a listxattr.
8bb8aefd 27 * The ones that start SYSTEM_ORANGEFS_KEY are the ones to avoid printing.
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28 */
29static int is_reserved_key(const char *key, size_t size)
30{
31
8bb8aefd 32 if (size < SYSTEM_ORANGEFS_KEY_LEN)
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33 return 1;
34
8bb8aefd 35 return strncmp(key, SYSTEM_ORANGEFS_KEY, SYSTEM_ORANGEFS_KEY_LEN) ? 1 : 0;
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36}
37
38static inline int convert_to_internal_xattr_flags(int setxattr_flags)
39{
40 int internal_flag = 0;
41
42 if (setxattr_flags & XATTR_REPLACE) {
43 /* Attribute must exist! */
8bb8aefd 44 internal_flag = ORANGEFS_XATTR_REPLACE;
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45 } else if (setxattr_flags & XATTR_CREATE) {
46 /* Attribute must not exist */
8bb8aefd 47 internal_flag = ORANGEFS_XATTR_CREATE;
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48 }
49 return internal_flag;
50}
51
52
53/*
54 * Tries to get a specified key's attributes of a given
55 * file into a user-specified buffer. Note that the getxattr
56 * interface allows for the users to probe the size of an
57 * extended attribute by passing in a value of 0 to size.
58 * Thus our return value is always the size of the attribute
59 * unless the key does not exist for the file and/or if
60 * there were errors in fetching the attribute value.
61 */
d373a712
AG
62ssize_t orangefs_inode_getxattr(struct inode *inode, const char *name,
63 void *buffer, size_t size)
1182fca3 64{
8bb8aefd
YL
65 struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
66 struct orangefs_kernel_op_s *new_op = NULL;
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67 ssize_t ret = -ENOMEM;
68 ssize_t length = 0;
69 int fsuid;
70 int fsgid;
71
72 gossip_debug(GOSSIP_XATTR_DEBUG,
d373a712
AG
73 "%s: name %s, buffer_size %zd\n",
74 __func__, name, size);
1182fca3 75
d373a712 76 if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) {
eeaa3d44 77 gossip_err("Invalid key length (%d)\n",
d373a712 78 (int)strlen(name));
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79 return -EINVAL;
80 }
81
78fee0b6
JH
82 fsuid = from_kuid(&init_user_ns, current_fsuid());
83 fsgid = from_kgid(&init_user_ns, current_fsgid());
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84
85 gossip_debug(GOSSIP_XATTR_DEBUG,
86 "getxattr on inode %pU, name %s "
87 "(uid %o, gid %o)\n",
88 get_khandle_from_ino(inode),
89 name,
90 fsuid,
91 fsgid);
92
8bb8aefd 93 down_read(&orangefs_inode->xattr_sem);
1182fca3 94
8bb8aefd 95 new_op = op_alloc(ORANGEFS_VFS_OP_GETXATTR);
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96 if (!new_op)
97 goto out_unlock;
98
8bb8aefd 99 new_op->upcall.req.getxattr.refn = orangefs_inode->refn;
d373a712 100 strcpy(new_op->upcall.req.getxattr.key, name);
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101
102 /*
103 * NOTE: Although keys are meant to be NULL terminated textual
104 * strings, I am going to explicitly pass the length just in case
105 * we change this later on...
106 */
d373a712 107 new_op->upcall.req.getxattr.key_sz = strlen(name) + 1;
1182fca3 108
8bb8aefd 109 ret = service_operation(new_op, "orangefs_inode_getxattr",
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110 get_interruptible_flag(inode));
111 if (ret != 0) {
112 if (ret == -ENOENT) {
113 ret = -ENODATA;
114 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 115 "orangefs_inode_getxattr: inode %pU key %s"
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116 " does not exist!\n",
117 get_khandle_from_ino(inode),
118 (char *)new_op->upcall.req.getxattr.key);
119 }
120 goto out_release_op;
121 }
122
123 /*
124 * Length returned includes null terminator.
125 */
126 length = new_op->downcall.resp.getxattr.val_sz;
127
128 /*
129 * Just return the length of the queried attribute.
130 */
131 if (size == 0) {
132 ret = length;
133 goto out_release_op;
134 }
135
136 /*
137 * Check to see if key length is > provided buffer size.
138 */
139 if (length > size) {
140 ret = -ERANGE;
141 goto out_release_op;
142 }
143
1182fca3 144 memcpy(buffer, new_op->downcall.resp.getxattr.val, length);
a9bb3ba8 145 memset(buffer + length, 0, size - length);
1182fca3 146 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 147 "orangefs_inode_getxattr: inode %pU "
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148 "key %s key_sz %d, val_len %d\n",
149 get_khandle_from_ino(inode),
150 (char *)new_op->
151 upcall.req.getxattr.key,
152 (int)new_op->
153 upcall.req.getxattr.key_sz,
154 (int)ret);
155
156 ret = length;
157
158out_release_op:
159 op_release(new_op);
160out_unlock:
8bb8aefd 161 up_read(&orangefs_inode->xattr_sem);
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162 return ret;
163}
164
d373a712
AG
165static int orangefs_inode_removexattr(struct inode *inode, const char *name,
166 int flags)
1182fca3 167{
8bb8aefd
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168 struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
169 struct orangefs_kernel_op_s *new_op = NULL;
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170 int ret = -ENOMEM;
171
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172 down_write(&orangefs_inode->xattr_sem);
173 new_op = op_alloc(ORANGEFS_VFS_OP_REMOVEXATTR);
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174 if (!new_op)
175 goto out_unlock;
176
8bb8aefd 177 new_op->upcall.req.removexattr.refn = orangefs_inode->refn;
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178 /*
179 * NOTE: Although keys are meant to be NULL terminated
180 * textual strings, I am going to explicitly pass the
181 * length just in case we change this later on...
182 */
d373a712
AG
183 strcpy(new_op->upcall.req.removexattr.key, name);
184 new_op->upcall.req.removexattr.key_sz = strlen(name) + 1;
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185
186 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 187 "orangefs_inode_removexattr: key %s, key_sz %d\n",
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188 (char *)new_op->upcall.req.removexattr.key,
189 (int)new_op->upcall.req.removexattr.key_sz);
190
191 ret = service_operation(new_op,
8bb8aefd 192 "orangefs_inode_removexattr",
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193 get_interruptible_flag(inode));
194 if (ret == -ENOENT) {
195 /*
196 * Request to replace a non-existent attribute is an error.
197 */
198 if (flags & XATTR_REPLACE)
199 ret = -ENODATA;
200 else
201 ret = 0;
202 }
203
204 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 205 "orangefs_inode_removexattr: returning %d\n", ret);
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206
207 op_release(new_op);
208out_unlock:
8bb8aefd 209 up_write(&orangefs_inode->xattr_sem);
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210 return ret;
211}
212
213/*
214 * Tries to set an attribute for a given key on a file.
215 *
216 * Returns a -ve number on error and 0 on success. Key is text, but value
217 * can be binary!
218 */
d373a712
AG
219int orangefs_inode_setxattr(struct inode *inode, const char *name,
220 const void *value, size_t size, int flags)
1182fca3 221{
8bb8aefd
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222 struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
223 struct orangefs_kernel_op_s *new_op;
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224 int internal_flag = 0;
225 int ret = -ENOMEM;
226
227 gossip_debug(GOSSIP_XATTR_DEBUG,
d373a712
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228 "%s: name %s, buffer_size %zd\n",
229 __func__, name, size);
1182fca3 230
2d09a2ca 231 if (size >= ORANGEFS_MAX_XATTR_VALUELEN ||
1182fca3 232 flags < 0) {
8bb8aefd 233 gossip_err("orangefs_inode_setxattr: bogus values of size(%d), flags(%d)\n",
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234 (int)size,
235 flags);
236 return -EINVAL;
237 }
238
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239 internal_flag = convert_to_internal_xattr_flags(flags);
240
d373a712
AG
241 if (strlen(name) >= ORANGEFS_MAX_XATTR_NAMELEN) {
242 gossip_err
243 ("orangefs_inode_setxattr: bogus key size (%d)\n",
244 (int)(strlen(name)));
245 return -EINVAL;
1182fca3
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246 }
247
248 /* This is equivalent to a removexattr */
249 if (size == 0 && value == NULL) {
250 gossip_debug(GOSSIP_XATTR_DEBUG,
d373a712 251 "removing xattr (%s)\n",
1182fca3 252 name);
d373a712 253 return orangefs_inode_removexattr(inode, name, flags);
1182fca3
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254 }
255
256 gossip_debug(GOSSIP_XATTR_DEBUG,
257 "setxattr on inode %pU, name %s\n",
258 get_khandle_from_ino(inode),
259 name);
260
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261 down_write(&orangefs_inode->xattr_sem);
262 new_op = op_alloc(ORANGEFS_VFS_OP_SETXATTR);
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263 if (!new_op)
264 goto out_unlock;
265
266
8bb8aefd 267 new_op->upcall.req.setxattr.refn = orangefs_inode->refn;
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268 new_op->upcall.req.setxattr.flags = internal_flag;
269 /*
270 * NOTE: Although keys are meant to be NULL terminated textual
271 * strings, I am going to explicitly pass the length just in
272 * case we change this later on...
273 */
d373a712
AG
274 strcpy(new_op->upcall.req.setxattr.keyval.key, name);
275 new_op->upcall.req.setxattr.keyval.key_sz = strlen(name) + 1;
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276 memcpy(new_op->upcall.req.setxattr.keyval.val, value, size);
277 new_op->upcall.req.setxattr.keyval.val_sz = size;
278
279 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 280 "orangefs_inode_setxattr: key %s, key_sz %d "
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281 " value size %zd\n",
282 (char *)new_op->upcall.req.setxattr.keyval.key,
283 (int)new_op->upcall.req.setxattr.keyval.key_sz,
284 size);
285
286 ret = service_operation(new_op,
8bb8aefd 287 "orangefs_inode_setxattr",
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288 get_interruptible_flag(inode));
289
290 gossip_debug(GOSSIP_XATTR_DEBUG,
8bb8aefd 291 "orangefs_inode_setxattr: returning %d\n",
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292 ret);
293
294 /* when request is serviced properly, free req op struct */
295 op_release(new_op);
296out_unlock:
8bb8aefd 297 up_write(&orangefs_inode->xattr_sem);
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298 return ret;
299}
300
301/*
302 * Tries to get a specified object's keys into a user-specified buffer of a
303 * given size. Note that like the previous instances of xattr routines, this
304 * also allows you to pass in a NULL pointer and 0 size to probe the size for
305 * subsequent memory allocations. Thus our return value is always the size of
306 * all the keys unless there were errors in fetching the keys!
307 */
8bb8aefd 308ssize_t orangefs_listxattr(struct dentry *dentry, char *buffer, size_t size)
1182fca3
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309{
310 struct inode *inode = dentry->d_inode;
8bb8aefd
YL
311 struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
312 struct orangefs_kernel_op_s *new_op;
313 __u64 token = ORANGEFS_ITERATE_START;
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314 ssize_t ret = -ENOMEM;
315 ssize_t total = 0;
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316 int count_keys = 0;
317 int key_size;
318 int i = 0;
62441fa5 319 int returned_count = 0;
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320
321 if (size > 0 && buffer == NULL) {
322 gossip_err("%s: bogus NULL pointers\n", __func__);
323 return -EINVAL;
324 }
1182fca3 325
8bb8aefd
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326 down_read(&orangefs_inode->xattr_sem);
327 new_op = op_alloc(ORANGEFS_VFS_OP_LISTXATTR);
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328 if (!new_op)
329 goto out_unlock;
330
331 if (buffer && size > 0)
332 memset(buffer, 0, size);
333
334try_again:
335 key_size = 0;
8bb8aefd 336 new_op->upcall.req.listxattr.refn = orangefs_inode->refn;
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337 new_op->upcall.req.listxattr.token = token;
338 new_op->upcall.req.listxattr.requested_count =
8bb8aefd 339 (size == 0) ? 0 : ORANGEFS_MAX_XATTR_LISTLEN;
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340 ret = service_operation(new_op, __func__,
341 get_interruptible_flag(inode));
342 if (ret != 0)
343 goto done;
344
345 if (size == 0) {
346 /*
347 * This is a bit of a big upper limit, but I did not want to
348 * spend too much time getting this correct, since users end
349 * up allocating memory rather than us...
350 */
351 total = new_op->downcall.resp.listxattr.returned_count *
8bb8aefd 352 ORANGEFS_MAX_XATTR_NAMELEN;
1182fca3
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353 goto done;
354 }
355
62441fa5
MM
356 returned_count = new_op->downcall.resp.listxattr.returned_count;
357 if (returned_count < 0 ||
358 returned_count >= ORANGEFS_MAX_XATTR_LISTLEN) {
359 gossip_err("%s: impossible value for returned_count:%d:\n",
360 __func__,
361 returned_count);
02a5cc53 362 ret = -EIO;
62441fa5
MM
363 goto done;
364 }
365
1182fca3
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366 /*
367 * Check to see how much can be fit in the buffer. Fit only whole keys.
368 */
62441fa5 369 for (i = 0; i < returned_count; i++) {
02a5cc53
MB
370 if (new_op->downcall.resp.listxattr.lengths[i] < 0 ||
371 new_op->downcall.resp.listxattr.lengths[i] >
372 ORANGEFS_MAX_XATTR_NAMELEN) {
373 gossip_err("%s: impossible value for lengths[%d]\n",
374 __func__,
375 new_op->downcall.resp.listxattr.lengths[i]);
376 ret = -EIO;
377 goto done;
378 }
1182fca3
MM
379 if (total + new_op->downcall.resp.listxattr.lengths[i] > size)
380 goto done;
381
382 /*
383 * Since many dumb programs try to setxattr() on our reserved
384 * xattrs this is a feeble attempt at defeating those by not
385 * listing them in the output of listxattr.. sigh
386 */
387 if (is_reserved_key(new_op->downcall.resp.listxattr.key +
388 key_size,
389 new_op->downcall.resp.
390 listxattr.lengths[i])) {
391 gossip_debug(GOSSIP_XATTR_DEBUG, "Copying key %d -> %s\n",
392 i, new_op->downcall.resp.listxattr.key +
393 key_size);
394 memcpy(buffer + total,
395 new_op->downcall.resp.listxattr.key + key_size,
396 new_op->downcall.resp.listxattr.lengths[i]);
397 total += new_op->downcall.resp.listxattr.lengths[i];
398 count_keys++;
399 } else {
400 gossip_debug(GOSSIP_XATTR_DEBUG, "[RESERVED] key %d -> %s\n",
401 i, new_op->downcall.resp.listxattr.key +
402 key_size);
403 }
404 key_size += new_op->downcall.resp.listxattr.lengths[i];
405 }
406
407 /*
408 * Since the buffer was large enough, we might have to continue
409 * fetching more keys!
410 */
411 token = new_op->downcall.resp.listxattr.token;
8bb8aefd 412 if (token != ORANGEFS_ITERATE_END)
1182fca3
MM
413 goto try_again;
414
415done:
416 gossip_debug(GOSSIP_XATTR_DEBUG, "%s: returning %d"
417 " [size of buffer %ld] (filled in %d keys)\n",
418 __func__,
419 ret ? (int)ret : (int)total,
420 (long)size,
421 count_keys);
422 op_release(new_op);
423 if (ret == 0)
424 ret = total;
425out_unlock:
8bb8aefd 426 up_read(&orangefs_inode->xattr_sem);
1182fca3
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427 return ret;
428}
429
8bb8aefd 430static int orangefs_xattr_set_default(const struct xattr_handler *handler,
59301226
AV
431 struct dentry *unused,
432 struct inode *inode,
8bb8aefd
YL
433 const char *name,
434 const void *buffer,
435 size_t size,
436 int flags)
1182fca3 437{
d373a712 438 return orangefs_inode_setxattr(inode, name, buffer, size, flags);
1182fca3
MM
439}
440
8bb8aefd 441static int orangefs_xattr_get_default(const struct xattr_handler *handler,
b296821a
AV
442 struct dentry *unused,
443 struct inode *inode,
8bb8aefd
YL
444 const char *name,
445 void *buffer,
446 size_t size)
1182fca3 447{
d373a712 448 return orangefs_inode_getxattr(inode, name, buffer, size);
1182fca3
MM
449
450}
451
8bb8aefd 452static struct xattr_handler orangefs_xattr_default_handler = {
972a7344 453 .prefix = "", /* match any name => handlers called with full name */
8bb8aefd
YL
454 .get = orangefs_xattr_get_default,
455 .set = orangefs_xattr_set_default,
1182fca3
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456};
457
8bb8aefd 458const struct xattr_handler *orangefs_xattr_handlers[] = {
1182fca3
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459 &posix_acl_access_xattr_handler,
460 &posix_acl_default_xattr_handler,
8bb8aefd 461 &orangefs_xattr_default_handler,
1182fca3
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462 NULL
463};