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afs: Introduce a file-private data record
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CommitLineData
1da177e4
LT
1/*
2 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
3 *
4 * This software may be freely redistributed under the terms of the
5 * GNU General Public License.
6 *
7 * You should have received a copy of the GNU General Public License
8 * along with this program; if not, write to the Free Software
9 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
10 *
44d1b980 11 * Authors: David Woodhouse <dwmw2@infradead.org>
1da177e4
LT
12 * David Howells <dhowells@redhat.com>
13 *
14 */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/init.h>
1da177e4
LT
19#include <linux/fs.h>
20#include <linux/pagemap.h>
e8edc6e0 21#include <linux/sched.h>
bec5eb61 22#include <linux/mount.h>
23#include <linux/namei.h>
1da177e4
LT
24#include "internal.h"
25
d3e3b7ea
DH
26static const struct inode_operations afs_symlink_inode_operations = {
27 .get_link = page_get_link,
28 .listxattr = afs_listxattr,
29};
30
1da177e4
LT
31/*
32 * map the AFS file status to the inode member variables
33 */
00d3b7a4 34static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
1da177e4
LT
35{
36 struct inode *inode = AFS_VNODE_TO_I(vnode);
c435ee34 37 bool changed;
1da177e4 38
260a9803 39 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
1da177e4
LT
40 vnode->status.type,
41 vnode->status.nlink,
ba3e0e1a 42 (unsigned long long) vnode->status.size,
08e0e7c8 43 vnode->status.data_version,
1da177e4
LT
44 vnode->status.mode);
45
c435ee34
DH
46 read_seqlock_excl(&vnode->cb_lock);
47
1da177e4
LT
48 switch (vnode->status.type) {
49 case AFS_FTYPE_FILE:
50 inode->i_mode = S_IFREG | vnode->status.mode;
51 inode->i_op = &afs_file_inode_operations;
00d3b7a4 52 inode->i_fop = &afs_file_operations;
1da177e4
LT
53 break;
54 case AFS_FTYPE_DIR:
55 inode->i_mode = S_IFDIR | vnode->status.mode;
56 inode->i_op = &afs_dir_inode_operations;
57 inode->i_fop = &afs_dir_file_operations;
58 break;
59 case AFS_FTYPE_SYMLINK:
944c74f4
DH
60 /* Symlinks with a mode of 0644 are actually mountpoints. */
61 if ((vnode->status.mode & 0777) == 0644) {
62 inode->i_flags |= S_AUTOMOUNT;
63
944c74f4 64 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
944c74f4
DH
65
66 inode->i_mode = S_IFDIR | 0555;
67 inode->i_op = &afs_mntpt_inode_operations;
68 inode->i_fop = &afs_mntpt_file_operations;
69 } else {
70 inode->i_mode = S_IFLNK | vnode->status.mode;
d3e3b7ea 71 inode->i_op = &afs_symlink_inode_operations;
944c74f4 72 }
21fc61c7 73 inode_nohighmem(inode);
1da177e4
LT
74 break;
75 default:
76 printk("kAFS: AFS vnode with undefined type\n");
c435ee34 77 read_sequnlock_excl(&vnode->cb_lock);
1da177e4
LT
78 return -EBADMSG;
79 }
80
c435ee34 81 changed = (vnode->status.size != inode->i_size);
9b3f26c9 82
bfe86848 83 set_nlink(inode, vnode->status.nlink);
1da177e4 84 inode->i_uid = vnode->status.owner;
6186f078 85 inode->i_gid = vnode->status.group;
1da177e4 86 inode->i_size = vnode->status.size;
ab94f5d0 87 inode->i_ctime.tv_sec = vnode->status.mtime_client;
1da177e4
LT
88 inode->i_ctime.tv_nsec = 0;
89 inode->i_atime = inode->i_mtime = inode->i_ctime;
1da177e4 90 inode->i_blocks = 0;
d6e43f75
DH
91 inode->i_generation = vnode->fid.unique;
92 inode->i_version = vnode->status.data_version;
1da177e4 93 inode->i_mapping->a_ops = &afs_fs_aops;
c435ee34
DH
94
95 read_sequnlock_excl(&vnode->cb_lock);
96
97#ifdef CONFIG_AFS_FSCACHE
98 if (changed)
99 fscache_attr_changed(vnode->cache);
100#endif
1da177e4 101 return 0;
ec26815a 102}
1da177e4 103
d2ddc776
DH
104/*
105 * Fetch file status from the volume.
106 */
107int afs_fetch_status(struct afs_vnode *vnode, struct key *key)
108{
109 struct afs_fs_cursor fc;
110 int ret;
111
112 _enter("%s,{%x:%u.%u,S=%lx}",
113 vnode->volume->name,
114 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
115 vnode->flags);
116
117 ret = -ERESTARTSYS;
118 if (afs_begin_vnode_operation(&fc, vnode, key)) {
119 while (afs_select_fileserver(&fc)) {
120 fc.cb_break = vnode->cb_break + vnode->cb_s_break;
121 afs_fs_fetch_file_status(&fc, NULL);
122 }
123
124 afs_check_for_remote_deletion(&fc, fc.vnode);
125 afs_vnode_commit_status(&fc, vnode, fc.cb_break);
126 ret = afs_end_vnode_operation(&fc);
127 }
128
129 _leave(" = %d", ret);
130 return ret;
131}
132
1da177e4
LT
133/*
134 * iget5() comparator
135 */
c435ee34 136int afs_iget5_test(struct inode *inode, void *opaque)
1da177e4
LT
137{
138 struct afs_iget_data *data = opaque;
139
140 return inode->i_ino == data->fid.vnode &&
d6e43f75 141 inode->i_generation == data->fid.unique;
ec26815a 142}
1da177e4 143
bec5eb61 144/*
145 * iget5() comparator for inode created by autocell operations
146 *
147 * These pseudo inodes don't match anything.
148 */
149static int afs_iget5_autocell_test(struct inode *inode, void *opaque)
150{
151 return 0;
152}
153
1da177e4
LT
154/*
155 * iget5() inode initialiser
156 */
157static int afs_iget5_set(struct inode *inode, void *opaque)
158{
159 struct afs_iget_data *data = opaque;
160 struct afs_vnode *vnode = AFS_FS_I(inode);
161
162 inode->i_ino = data->fid.vnode;
d6e43f75 163 inode->i_generation = data->fid.unique;
1da177e4
LT
164 vnode->fid = data->fid;
165 vnode->volume = data->volume;
166
167 return 0;
ec26815a 168}
1da177e4 169
bec5eb61 170/*
171 * inode retrieval for autocell
172 */
173struct inode *afs_iget_autocell(struct inode *dir, const char *dev_name,
174 int namesz, struct key *key)
175{
176 struct afs_iget_data data;
177 struct afs_super_info *as;
178 struct afs_vnode *vnode;
179 struct super_block *sb;
180 struct inode *inode;
181 static atomic_t afs_autocell_ino;
182
183 _enter("{%x:%u},%*.*s,",
184 AFS_FS_I(dir)->fid.vid, AFS_FS_I(dir)->fid.vnode,
185 namesz, namesz, dev_name ?: "");
186
187 sb = dir->i_sb;
188 as = sb->s_fs_info;
189 data.volume = as->volume;
190 data.fid.vid = as->volume->vid;
191 data.fid.unique = 0;
192 data.fid.vnode = 0;
193
194 inode = iget5_locked(sb, atomic_inc_return(&afs_autocell_ino),
195 afs_iget5_autocell_test, afs_iget5_set,
196 &data);
197 if (!inode) {
198 _leave(" = -ENOMEM");
199 return ERR_PTR(-ENOMEM);
200 }
201
202 _debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
203 inode, inode->i_ino, data.fid.vid, data.fid.vnode,
204 data.fid.unique);
205
206 vnode = AFS_FS_I(inode);
207
208 /* there shouldn't be an existing inode */
209 BUG_ON(!(inode->i_state & I_NEW));
210
211 inode->i_size = 0;
212 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
213 inode->i_op = &afs_autocell_inode_operations;
bfe86848 214 set_nlink(inode, 2);
a0a5386a
EB
215 inode->i_uid = GLOBAL_ROOT_UID;
216 inode->i_gid = GLOBAL_ROOT_GID;
bec5eb61 217 inode->i_ctime.tv_sec = get_seconds();
218 inode->i_ctime.tv_nsec = 0;
219 inode->i_atime = inode->i_mtime = inode->i_ctime;
220 inode->i_blocks = 0;
221 inode->i_version = 0;
222 inode->i_generation = 0;
223
224 set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
d18610b0
DH
225 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
226 inode->i_flags |= S_AUTOMOUNT | S_NOATIME;
bec5eb61 227 unlock_new_inode(inode);
228 _leave(" = %p", inode);
229 return inode;
230}
231
1da177e4
LT
232/*
233 * inode retrieval
234 */
260a9803
DH
235struct inode *afs_iget(struct super_block *sb, struct key *key,
236 struct afs_fid *fid, struct afs_file_status *status,
d2ddc776 237 struct afs_callback *cb, struct afs_cb_interest *cbi)
1da177e4
LT
238{
239 struct afs_iget_data data = { .fid = *fid };
240 struct afs_super_info *as;
241 struct afs_vnode *vnode;
242 struct inode *inode;
243 int ret;
244
416351f2 245 _enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
1da177e4
LT
246
247 as = sb->s_fs_info;
248 data.volume = as->volume;
249
250 inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
251 &data);
252 if (!inode) {
253 _leave(" = -ENOMEM");
08e0e7c8 254 return ERR_PTR(-ENOMEM);
1da177e4
LT
255 }
256
08e0e7c8
DH
257 _debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
258 inode, fid->vid, fid->vnode, fid->unique);
259
1da177e4
LT
260 vnode = AFS_FS_I(inode);
261
262 /* deal with an existing inode */
263 if (!(inode->i_state & I_NEW)) {
08e0e7c8
DH
264 _leave(" = %p", inode);
265 return inode;
1da177e4
LT
266 }
267
260a9803
DH
268 if (!status) {
269 /* it's a remotely extant inode */
d2ddc776 270 ret = afs_fetch_status(vnode, key);
260a9803
DH
271 if (ret < 0)
272 goto bad_inode;
273 } else {
274 /* it's an inode we just created */
275 memcpy(&vnode->status, status, sizeof(vnode->status));
276
277 if (!cb) {
278 /* it's a symlink we just created (the fileserver
279 * didn't give us a callback) */
280 vnode->cb_version = 0;
260a9803 281 vnode->cb_type = 0;
c435ee34 282 vnode->cb_expires_at = 0;
260a9803
DH
283 } else {
284 vnode->cb_version = cb->version;
260a9803 285 vnode->cb_type = cb->type;
c435ee34 286 vnode->cb_expires_at = cb->expiry;
d2ddc776 287 vnode->cb_interest = afs_get_cb_interest(cbi);
c435ee34 288 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
260a9803 289 }
c435ee34
DH
290
291 vnode->cb_expires_at += ktime_get_real_seconds();
260a9803
DH
292 }
293
9b3f26c9
DH
294 /* set up caching before mapping the status, as map-status reads the
295 * first page of symlinks to see if they're really mountpoints */
296 inode->i_size = vnode->status.size;
297#ifdef CONFIG_AFS_FSCACHE
298 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
299 &afs_vnode_cache_index_def,
94d30ae9 300 vnode, true);
9b3f26c9
DH
301#endif
302
00d3b7a4 303 ret = afs_inode_map_status(vnode, key);
08e0e7c8 304 if (ret < 0)
1da177e4
LT
305 goto bad_inode;
306
307 /* success */
260a9803 308 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
08e0e7c8 309 inode->i_flags |= S_NOATIME;
1da177e4 310 unlock_new_inode(inode);
08e0e7c8
DH
311 _leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
312 return inode;
1da177e4
LT
313
314 /* failure */
ec26815a 315bad_inode:
9b3f26c9
DH
316#ifdef CONFIG_AFS_FSCACHE
317 fscache_relinquish_cookie(vnode->cache, 0);
318 vnode->cache = NULL;
319#endif
aa7fa240 320 iget_failed(inode);
1da177e4 321 _leave(" = %d [bad]", ret);
08e0e7c8 322 return ERR_PTR(ret);
ec26815a 323}
1da177e4 324
416351f2
DH
325/*
326 * mark the data attached to an inode as obsolete due to a write on the server
327 * - might also want to ditch all the outstanding writes and dirty pages
328 */
329void afs_zap_data(struct afs_vnode *vnode)
330{
0f300ca9 331 _enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
416351f2
DH
332
333 /* nuke all the non-dirty pages that aren't locked, mapped or being
0f300ca9
DH
334 * written back in a regular file and completely discard the pages in a
335 * directory or symlink */
336 if (S_ISREG(vnode->vfs_inode.i_mode))
337 invalidate_remote_inode(&vnode->vfs_inode);
338 else
339 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
416351f2
DH
340}
341
260a9803
DH
342/*
343 * validate a vnode/inode
344 * - there are several things we need to check
345 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
346 * symlink)
347 * - parent dir metadata changed (security changes)
348 * - dentry data changed (write, truncate)
349 * - dentry metadata changed (security changes)
350 */
351int afs_validate(struct afs_vnode *vnode, struct key *key)
352{
c435ee34
DH
353 time64_t now = ktime_get_real_seconds();
354 bool valid = false;
260a9803
DH
355 int ret;
356
357 _enter("{v={%x:%u} fl=%lx},%x",
358 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
359 key_serial(key));
360
c435ee34
DH
361 /* Quickly check the callback state. Ideally, we'd use read_seqbegin
362 * here, but we have no way to pass the net namespace to the RCU
363 * cleanup for the server record.
364 */
365 read_seqlock_excl(&vnode->cb_lock);
366
367 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
368 if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break) {
369 vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;
370 } else if (!test_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags) &&
371 !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
372 vnode->cb_expires_at - 10 > now) {
373 valid = true;
260a9803 374 }
c435ee34
DH
375 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
376 valid = true;
260a9803
DH
377 }
378
c435ee34
DH
379 read_sequnlock_excl(&vnode->cb_lock);
380 if (valid)
260a9803
DH
381 goto valid;
382
383 mutex_lock(&vnode->validate_lock);
384
385 /* if the promise has expired, we need to check the server again to get
386 * a new promise - note that if the (parent) directory's metadata was
387 * changed then the security may be different and we may no longer have
388 * access */
c435ee34 389 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
260a9803 390 _debug("not promised");
d2ddc776 391 ret = afs_fetch_status(vnode, key);
c435ee34
DH
392 if (ret < 0) {
393 if (ret == -ENOENT) {
394 set_bit(AFS_VNODE_DELETED, &vnode->flags);
395 ret = -ESTALE;
396 }
260a9803 397 goto error_unlock;
c435ee34 398 }
260a9803
DH
399 _debug("new promise [fl=%lx]", vnode->flags);
400 }
401
402 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
403 _debug("file already deleted");
404 ret = -ESTALE;
405 goto error_unlock;
406 }
407
408 /* if the vnode's data version number changed then its contents are
409 * different */
416351f2
DH
410 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
411 afs_zap_data(vnode);
260a9803 412
c435ee34 413 clear_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags);
260a9803
DH
414 mutex_unlock(&vnode->validate_lock);
415valid:
416 _leave(" = 0");
417 return 0;
418
419error_unlock:
420 mutex_unlock(&vnode->validate_lock);
421 _leave(" = %d", ret);
422 return ret;
423}
424
1da177e4
LT
425/*
426 * read the attributes of an inode
427 */
a528d35e
DH
428int afs_getattr(const struct path *path, struct kstat *stat,
429 u32 request_mask, unsigned int query_flags)
1da177e4 430{
a528d35e 431 struct inode *inode = d_inode(path->dentry);
c435ee34
DH
432 struct afs_vnode *vnode = AFS_FS_I(inode);
433 int seq = 0;
1da177e4 434
d6e43f75 435 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
1da177e4 436
c435ee34
DH
437 do {
438 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
439 generic_fillattr(inode, stat);
440 } while (need_seqretry(&vnode->cb_lock, seq));
441
442 done_seqretry(&vnode->cb_lock, seq);
1da177e4 443 return 0;
ec26815a 444}
1da177e4 445
bec5eb61 446/*
447 * discard an AFS inode
448 */
449int afs_drop_inode(struct inode *inode)
450{
451 _enter("");
452
453 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
454 return generic_delete_inode(inode);
455 else
456 return generic_drop_inode(inode);
457}
458
1da177e4
LT
459/*
460 * clear an AFS inode
461 */
b57922d9 462void afs_evict_inode(struct inode *inode)
1da177e4
LT
463{
464 struct afs_vnode *vnode;
465
466 vnode = AFS_FS_I(inode);
467
c435ee34 468 _enter("{%x:%u.%d}",
260a9803 469 vnode->fid.vid,
1da177e4 470 vnode->fid.vnode,
c435ee34 471 vnode->fid.unique);
1da177e4 472
08e0e7c8
DH
473 _debug("CLEAR INODE %p", inode);
474
475 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
476
91b0abe3 477 truncate_inode_pages_final(&inode->i_data);
dbd5768f 478 clear_inode(inode);
b57922d9 479
c435ee34
DH
480 if (vnode->cb_interest) {
481 afs_put_cb_interest(afs_i2net(inode), vnode->cb_interest);
482 vnode->cb_interest = NULL;
08e0e7c8 483 }
1da177e4 484
31143d5d 485 ASSERT(list_empty(&vnode->writebacks));
1da177e4 486
9b3f26c9
DH
487#ifdef CONFIG_AFS_FSCACHE
488 fscache_relinquish_cookie(vnode->cache, 0);
1da177e4
LT
489 vnode->cache = NULL;
490#endif
491
be080a6f 492 afs_put_permits(vnode->permit_cache);
1da177e4 493 _leave("");
ec26815a 494}
31143d5d
DH
495
496/*
497 * set the attributes of an inode
498 */
499int afs_setattr(struct dentry *dentry, struct iattr *attr)
500{
d2ddc776 501 struct afs_fs_cursor fc;
2b0143b5 502 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
31143d5d
DH
503 struct key *key;
504 int ret;
505
a455589f
AV
506 _enter("{%x:%u},{n=%pd},%x",
507 vnode->fid.vid, vnode->fid.vnode, dentry,
31143d5d
DH
508 attr->ia_valid);
509
510 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
511 ATTR_MTIME))) {
512 _leave(" = 0 [unsupported]");
513 return 0;
514 }
515
516 /* flush any dirty data outstanding on a regular file */
517 if (S_ISREG(vnode->vfs_inode.i_mode)) {
518 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
519 afs_writeback_all(vnode);
520 }
521
522 if (attr->ia_valid & ATTR_FILE) {
215804a9 523 key = afs_file_key(attr->ia_file);
31143d5d
DH
524 } else {
525 key = afs_request_key(vnode->volume->cell);
526 if (IS_ERR(key)) {
527 ret = PTR_ERR(key);
528 goto error;
529 }
530 }
531
d2ddc776
DH
532 ret = -ERESTARTSYS;
533 if (afs_begin_vnode_operation(&fc, vnode, key)) {
534 while (afs_select_fileserver(&fc)) {
535 fc.cb_break = vnode->cb_break + vnode->cb_s_break;
536 afs_fs_setattr(&fc, attr);
537 }
538
539 afs_check_for_remote_deletion(&fc, fc.vnode);
540 afs_vnode_commit_status(&fc, vnode, fc.cb_break);
541 ret = afs_end_vnode_operation(&fc);
542 }
543
31143d5d
DH
544 if (!(attr->ia_valid & ATTR_FILE))
545 key_put(key);
546
547error:
548 _leave(" = %d", ret);
549 return ret;
550}