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 *
11 * Authors: David Woodhouse <dwmw2@infradead.org>
12 * David Howells <dhowells@redhat.com>
13 *
14 */
15
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/fs.h>
20 #include <linux/pagemap.h>
21 #include <linux/sched.h>
22 #include <linux/mount.h>
23 #include <linux/namei.h>
24 #include <linux/iversion.h>
25 #include "internal.h"
26 #include "afs_fs.h"
27
28 static const struct inode_operations afs_symlink_inode_operations = {
29 .get_link = page_get_link,
30 };
31
dump_vnode(struct afs_vnode * vnode,struct afs_vnode * parent_vnode)32 static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
33 {
34 static unsigned long once_only;
35
36 pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);
37 pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
38 vnode->status.abort_code,
39 vnode->status.mode,
40 vnode->status.size,
41 vnode->status.data_version);
42 pr_warn("kAFS: vnode %llx:%llx:%x\n",
43 vnode->fid.vid,
44 vnode->fid.vnode,
45 vnode->fid.unique);
46 if (parent_vnode)
47 pr_warn("kAFS: dir %llx:%llx:%x\n",
48 parent_vnode->fid.vid,
49 parent_vnode->fid.vnode,
50 parent_vnode->fid.unique);
51
52 if (!test_and_set_bit(0, &once_only))
53 dump_stack();
54 }
55
56 /*
57 * Initialise an inode from the vnode status.
58 */
afs_inode_init_from_status(struct afs_operation * op,struct afs_vnode_param * vp,struct afs_vnode * vnode)59 static int afs_inode_init_from_status(struct afs_operation *op,
60 struct afs_vnode_param *vp,
61 struct afs_vnode *vnode)
62 {
63 struct afs_file_status *status = &vp->scb.status;
64 struct inode *inode = AFS_VNODE_TO_I(vnode);
65 struct timespec64 t;
66
67 _enter("{%llx:%llu.%u} %s",
68 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
69 op->type ? op->type->name : "???");
70
71 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
72 status->type,
73 status->nlink,
74 (unsigned long long) status->size,
75 status->data_version,
76 status->mode);
77
78 write_seqlock(&vnode->cb_lock);
79
80 vnode->cb_v_break = op->cb_v_break;
81 vnode->cb_s_break = op->cb_s_break;
82 vnode->status = *status;
83
84 t = status->mtime_client;
85 inode->i_ctime = t;
86 inode->i_mtime = t;
87 inode->i_atime = t;
88 inode->i_flags |= S_NOATIME;
89 inode->i_uid = make_kuid(&init_user_ns, status->owner);
90 inode->i_gid = make_kgid(&init_user_ns, status->group);
91 set_nlink(&vnode->vfs_inode, status->nlink);
92
93 switch (status->type) {
94 case AFS_FTYPE_FILE:
95 inode->i_mode = S_IFREG | (status->mode & S_IALLUGO);
96 inode->i_op = &afs_file_inode_operations;
97 inode->i_fop = &afs_file_operations;
98 inode->i_mapping->a_ops = &afs_fs_aops;
99 break;
100 case AFS_FTYPE_DIR:
101 inode->i_mode = S_IFDIR | (status->mode & S_IALLUGO);
102 inode->i_op = &afs_dir_inode_operations;
103 inode->i_fop = &afs_dir_file_operations;
104 inode->i_mapping->a_ops = &afs_dir_aops;
105 break;
106 case AFS_FTYPE_SYMLINK:
107 /* Symlinks with a mode of 0644 are actually mountpoints. */
108 if ((status->mode & 0777) == 0644) {
109 inode->i_flags |= S_AUTOMOUNT;
110
111 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
112
113 inode->i_mode = S_IFDIR | 0555;
114 inode->i_op = &afs_mntpt_inode_operations;
115 inode->i_fop = &afs_mntpt_file_operations;
116 inode->i_mapping->a_ops = &afs_fs_aops;
117 } else {
118 inode->i_mode = S_IFLNK | status->mode;
119 inode->i_op = &afs_symlink_inode_operations;
120 inode->i_mapping->a_ops = &afs_fs_aops;
121 }
122 inode_nohighmem(inode);
123 break;
124 default:
125 dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
126 write_sequnlock(&vnode->cb_lock);
127 return afs_protocol_error(NULL, afs_eproto_file_type);
128 }
129
130 afs_set_i_size(vnode, status->size);
131
132 vnode->invalid_before = status->data_version;
133 inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
134
135 if (!vp->scb.have_cb) {
136 /* it's a symlink we just created (the fileserver
137 * didn't give us a callback) */
138 vnode->cb_expires_at = ktime_get_real_seconds();
139 } else {
140 vnode->cb_expires_at = vp->scb.callback.expires_at;
141 vnode->cb_server = op->server;
142 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
143 }
144
145 write_sequnlock(&vnode->cb_lock);
146 return 0;
147 }
148
149 /*
150 * Update the core inode struct from a returned status record.
151 */
afs_apply_status(struct afs_operation * op,struct afs_vnode_param * vp)152 static void afs_apply_status(struct afs_operation *op,
153 struct afs_vnode_param *vp)
154 {
155 struct afs_file_status *status = &vp->scb.status;
156 struct afs_vnode *vnode = vp->vnode;
157 struct inode *inode = &vnode->vfs_inode;
158 struct timespec64 t;
159 umode_t mode;
160 bool data_changed = false;
161 bool change_size = vp->set_size;
162
163 _enter("{%llx:%llu.%u} %s",
164 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
165 op->type ? op->type->name : "???");
166
167 BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
168
169 if (status->type != vnode->status.type) {
170 pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",
171 vnode->fid.vid,
172 vnode->fid.vnode,
173 vnode->fid.unique,
174 status->type, vnode->status.type);
175 afs_protocol_error(NULL, afs_eproto_bad_status);
176 return;
177 }
178
179 if (status->nlink != vnode->status.nlink)
180 set_nlink(inode, status->nlink);
181
182 if (status->owner != vnode->status.owner)
183 inode->i_uid = make_kuid(&init_user_ns, status->owner);
184
185 if (status->group != vnode->status.group)
186 inode->i_gid = make_kgid(&init_user_ns, status->group);
187
188 if (status->mode != vnode->status.mode) {
189 mode = inode->i_mode;
190 mode &= ~S_IALLUGO;
191 mode |= status->mode & S_IALLUGO;
192 WRITE_ONCE(inode->i_mode, mode);
193 }
194
195 t = status->mtime_client;
196 inode->i_mtime = t;
197 if (vp->update_ctime)
198 inode->i_ctime = op->ctime;
199
200 if (vnode->status.data_version != status->data_version)
201 data_changed = true;
202
203 vnode->status = *status;
204
205 if (vp->dv_before + vp->dv_delta != status->data_version) {
206 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags))
207 pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s\n",
208 vnode->fid.vid, vnode->fid.vnode,
209 (unsigned long long)vp->dv_before + vp->dv_delta,
210 (unsigned long long)status->data_version,
211 op->type ? op->type->name : "???");
212
213 vnode->invalid_before = status->data_version;
214 if (vnode->status.type == AFS_FTYPE_DIR) {
215 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
216 afs_stat_v(vnode, n_inval);
217 } else {
218 set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
219 }
220 change_size = true;
221 } else if (vnode->status.type == AFS_FTYPE_DIR) {
222 /* Expected directory change is handled elsewhere so
223 * that we can locally edit the directory and save on a
224 * download.
225 */
226 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
227 data_changed = false;
228 change_size = true;
229 }
230
231 if (data_changed) {
232 inode_set_iversion_raw(inode, status->data_version);
233
234 /* Only update the size if the data version jumped. If the
235 * file is being modified locally, then we might have our own
236 * idea of what the size should be that's not the same as
237 * what's on the server.
238 */
239 if (change_size) {
240 afs_set_i_size(vnode, status->size);
241 inode->i_ctime = t;
242 inode->i_atime = t;
243 }
244 }
245 }
246
247 /*
248 * Apply a callback to a vnode.
249 */
afs_apply_callback(struct afs_operation * op,struct afs_vnode_param * vp)250 static void afs_apply_callback(struct afs_operation *op,
251 struct afs_vnode_param *vp)
252 {
253 struct afs_callback *cb = &vp->scb.callback;
254 struct afs_vnode *vnode = vp->vnode;
255
256 if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
257 vnode->cb_expires_at = cb->expires_at;
258 vnode->cb_server = op->server;
259 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
260 }
261 }
262
263 /*
264 * Apply the received status and callback to an inode all in the same critical
265 * section to avoid races with afs_validate().
266 */
afs_vnode_commit_status(struct afs_operation * op,struct afs_vnode_param * vp)267 void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
268 {
269 struct afs_vnode *vnode = vp->vnode;
270
271 _enter("");
272
273 write_seqlock(&vnode->cb_lock);
274
275 if (vp->scb.have_error) {
276 /* A YFS server will return this from RemoveFile2 and AFS and
277 * YFS will return this from InlineBulkStatus.
278 */
279 if (vp->scb.status.abort_code == VNOVNODE) {
280 set_bit(AFS_VNODE_DELETED, &vnode->flags);
281 clear_nlink(&vnode->vfs_inode);
282 __afs_break_callback(vnode, afs_cb_break_for_deleted);
283 op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
284 }
285 } else if (vp->scb.have_status) {
286 if (vp->speculative &&
287 (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
288 vp->dv_before != vnode->status.data_version))
289 /* Ignore the result of a speculative bulk status fetch
290 * if it splits around a modification op, thereby
291 * appearing to regress the data version.
292 */
293 goto out;
294 afs_apply_status(op, vp);
295 if (vp->scb.have_cb)
296 afs_apply_callback(op, vp);
297 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
298 drop_nlink(&vnode->vfs_inode);
299 if (vnode->vfs_inode.i_nlink == 0) {
300 set_bit(AFS_VNODE_DELETED, &vnode->flags);
301 __afs_break_callback(vnode, afs_cb_break_for_deleted);
302 }
303 }
304
305 out:
306 write_sequnlock(&vnode->cb_lock);
307
308 if (vp->scb.have_status)
309 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
310 }
311
afs_fetch_status_success(struct afs_operation * op)312 static void afs_fetch_status_success(struct afs_operation *op)
313 {
314 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
315 struct afs_vnode *vnode = vp->vnode;
316 int ret;
317
318 if (vnode->vfs_inode.i_state & I_NEW) {
319 ret = afs_inode_init_from_status(op, vp, vnode);
320 op->error = ret;
321 if (ret == 0)
322 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
323 } else {
324 afs_vnode_commit_status(op, vp);
325 }
326 }
327
328 const struct afs_operation_ops afs_fetch_status_operation = {
329 .issue_afs_rpc = afs_fs_fetch_status,
330 .issue_yfs_rpc = yfs_fs_fetch_status,
331 .success = afs_fetch_status_success,
332 .aborted = afs_check_for_remote_deletion,
333 };
334
335 /*
336 * Fetch file status from the volume.
337 */
afs_fetch_status(struct afs_vnode * vnode,struct key * key,bool is_new,afs_access_t * _caller_access)338 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
339 afs_access_t *_caller_access)
340 {
341 struct afs_operation *op;
342
343 _enter("%s,{%llx:%llu.%u,S=%lx}",
344 vnode->volume->name,
345 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
346 vnode->flags);
347
348 op = afs_alloc_operation(key, vnode->volume);
349 if (IS_ERR(op))
350 return PTR_ERR(op);
351
352 afs_op_set_vnode(op, 0, vnode);
353
354 op->nr_files = 1;
355 op->ops = &afs_fetch_status_operation;
356 afs_begin_vnode_operation(op);
357 afs_wait_for_operation(op);
358
359 if (_caller_access)
360 *_caller_access = op->file[0].scb.status.caller_access;
361 return afs_put_operation(op);
362 }
363
364 /*
365 * ilookup() comparator
366 */
afs_ilookup5_test_by_fid(struct inode * inode,void * opaque)367 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
368 {
369 struct afs_vnode *vnode = AFS_FS_I(inode);
370 struct afs_fid *fid = opaque;
371
372 return (fid->vnode == vnode->fid.vnode &&
373 fid->vnode_hi == vnode->fid.vnode_hi &&
374 fid->unique == vnode->fid.unique);
375 }
376
377 /*
378 * iget5() comparator
379 */
afs_iget5_test(struct inode * inode,void * opaque)380 static int afs_iget5_test(struct inode *inode, void *opaque)
381 {
382 struct afs_vnode_param *vp = opaque;
383 //struct afs_vnode *vnode = AFS_FS_I(inode);
384
385 return afs_ilookup5_test_by_fid(inode, &vp->fid);
386 }
387
388 /*
389 * iget5() inode initialiser
390 */
afs_iget5_set(struct inode * inode,void * opaque)391 static int afs_iget5_set(struct inode *inode, void *opaque)
392 {
393 struct afs_vnode_param *vp = opaque;
394 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
395 struct afs_vnode *vnode = AFS_FS_I(inode);
396
397 vnode->volume = as->volume;
398 vnode->fid = vp->fid;
399
400 /* YFS supports 96-bit vnode IDs, but Linux only supports
401 * 64-bit inode numbers.
402 */
403 inode->i_ino = vnode->fid.vnode;
404 inode->i_generation = vnode->fid.unique;
405 return 0;
406 }
407
408 /*
409 * Get a cache cookie for an inode.
410 */
afs_get_inode_cache(struct afs_vnode * vnode)411 static void afs_get_inode_cache(struct afs_vnode *vnode)
412 {
413 #ifdef CONFIG_AFS_FSCACHE
414 struct {
415 u32 vnode_id;
416 u32 unique;
417 u32 vnode_id_ext[2]; /* Allow for a 96-bit key */
418 } __packed key;
419 struct afs_vnode_cache_aux aux;
420
421 if (vnode->status.type == AFS_FTYPE_DIR) {
422 vnode->cache = NULL;
423 return;
424 }
425
426 key.vnode_id = vnode->fid.vnode;
427 key.unique = vnode->fid.unique;
428 key.vnode_id_ext[0] = vnode->fid.vnode >> 32;
429 key.vnode_id_ext[1] = vnode->fid.vnode_hi;
430 aux.data_version = vnode->status.data_version;
431
432 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
433 &afs_vnode_cache_index_def,
434 &key, sizeof(key),
435 &aux, sizeof(aux),
436 vnode, vnode->status.size, true);
437 #endif
438 }
439
440 /*
441 * inode retrieval
442 */
afs_iget(struct afs_operation * op,struct afs_vnode_param * vp)443 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
444 {
445 struct afs_vnode_param *dvp = &op->file[0];
446 struct super_block *sb = dvp->vnode->vfs_inode.i_sb;
447 struct afs_vnode *vnode;
448 struct inode *inode;
449 int ret;
450
451 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
452
453 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
454 if (!inode) {
455 _leave(" = -ENOMEM");
456 return ERR_PTR(-ENOMEM);
457 }
458
459 vnode = AFS_FS_I(inode);
460
461 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
462 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
463
464 /* deal with an existing inode */
465 if (!(inode->i_state & I_NEW)) {
466 _leave(" = %p", inode);
467 return inode;
468 }
469
470 ret = afs_inode_init_from_status(op, vp, vnode);
471 if (ret < 0)
472 goto bad_inode;
473
474 afs_get_inode_cache(vnode);
475
476 /* success */
477 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
478 unlock_new_inode(inode);
479 _leave(" = %p", inode);
480 return inode;
481
482 /* failure */
483 bad_inode:
484 iget_failed(inode);
485 _leave(" = %d [bad]", ret);
486 return ERR_PTR(ret);
487 }
488
afs_iget5_set_root(struct inode * inode,void * opaque)489 static int afs_iget5_set_root(struct inode *inode, void *opaque)
490 {
491 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
492 struct afs_vnode *vnode = AFS_FS_I(inode);
493
494 vnode->volume = as->volume;
495 vnode->fid.vid = as->volume->vid,
496 vnode->fid.vnode = 1;
497 vnode->fid.unique = 1;
498 inode->i_ino = 1;
499 inode->i_generation = 1;
500 return 0;
501 }
502
503 /*
504 * Set up the root inode for a volume. This is always vnode 1, unique 1 within
505 * the volume.
506 */
afs_root_iget(struct super_block * sb,struct key * key)507 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
508 {
509 struct afs_super_info *as = AFS_FS_S(sb);
510 struct afs_operation *op;
511 struct afs_vnode *vnode;
512 struct inode *inode;
513 int ret;
514
515 _enter(",{%llx},,", as->volume->vid);
516
517 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
518 if (!inode) {
519 _leave(" = -ENOMEM");
520 return ERR_PTR(-ENOMEM);
521 }
522
523 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
524
525 BUG_ON(!(inode->i_state & I_NEW));
526
527 vnode = AFS_FS_I(inode);
528 vnode->cb_v_break = as->volume->cb_v_break,
529
530 op = afs_alloc_operation(key, as->volume);
531 if (IS_ERR(op)) {
532 ret = PTR_ERR(op);
533 goto error;
534 }
535
536 afs_op_set_vnode(op, 0, vnode);
537
538 op->nr_files = 1;
539 op->ops = &afs_fetch_status_operation;
540 ret = afs_do_sync_operation(op);
541 if (ret < 0)
542 goto error;
543
544 afs_get_inode_cache(vnode);
545
546 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
547 unlock_new_inode(inode);
548 _leave(" = %p", inode);
549 return inode;
550
551 error:
552 iget_failed(inode);
553 _leave(" = %d [bad]", ret);
554 return ERR_PTR(ret);
555 }
556
557 /*
558 * mark the data attached to an inode as obsolete due to a write on the server
559 * - might also want to ditch all the outstanding writes and dirty pages
560 */
afs_zap_data(struct afs_vnode * vnode)561 static void afs_zap_data(struct afs_vnode *vnode)
562 {
563 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
564
565 #ifdef CONFIG_AFS_FSCACHE
566 fscache_invalidate(vnode->cache);
567 #endif
568
569 /* nuke all the non-dirty pages that aren't locked, mapped or being
570 * written back in a regular file and completely discard the pages in a
571 * directory or symlink */
572 if (S_ISREG(vnode->vfs_inode.i_mode))
573 invalidate_remote_inode(&vnode->vfs_inode);
574 else
575 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
576 }
577
578 /*
579 * Get the server reinit counter for a vnode's current server.
580 */
afs_get_s_break_rcu(struct afs_vnode * vnode,unsigned int * _s_break)581 static bool afs_get_s_break_rcu(struct afs_vnode *vnode, unsigned int *_s_break)
582 {
583 struct afs_server_list *slist = rcu_dereference(vnode->volume->servers);
584 struct afs_server *server;
585 int i;
586
587 for (i = 0; i < slist->nr_servers; i++) {
588 server = slist->servers[i].server;
589 if (server == vnode->cb_server) {
590 *_s_break = READ_ONCE(server->cb_s_break);
591 return true;
592 }
593 }
594
595 return false;
596 }
597
598 /*
599 * Check the validity of a vnode/inode.
600 */
afs_check_validity(struct afs_vnode * vnode)601 bool afs_check_validity(struct afs_vnode *vnode)
602 {
603 struct afs_volume *volume = vnode->volume;
604 enum afs_cb_break_reason need_clear = afs_cb_break_no_break;
605 time64_t now = ktime_get_real_seconds();
606 bool valid;
607 unsigned int cb_break, cb_s_break, cb_v_break;
608 int seq = 0;
609
610 do {
611 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
612 cb_v_break = READ_ONCE(volume->cb_v_break);
613 cb_break = vnode->cb_break;
614
615 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&
616 afs_get_s_break_rcu(vnode, &cb_s_break)) {
617 if (vnode->cb_s_break != cb_s_break ||
618 vnode->cb_v_break != cb_v_break) {
619 vnode->cb_s_break = cb_s_break;
620 vnode->cb_v_break = cb_v_break;
621 need_clear = afs_cb_break_for_vsbreak;
622 valid = false;
623 } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
624 need_clear = afs_cb_break_for_zap;
625 valid = false;
626 } else if (vnode->cb_expires_at - 10 <= now) {
627 need_clear = afs_cb_break_for_lapsed;
628 valid = false;
629 } else {
630 valid = true;
631 }
632 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
633 valid = true;
634 } else {
635 vnode->cb_v_break = cb_v_break;
636 valid = false;
637 }
638
639 } while (need_seqretry(&vnode->cb_lock, seq));
640
641 done_seqretry(&vnode->cb_lock, seq);
642
643 if (need_clear != afs_cb_break_no_break) {
644 write_seqlock(&vnode->cb_lock);
645 if (cb_break == vnode->cb_break)
646 __afs_break_callback(vnode, need_clear);
647 else
648 trace_afs_cb_miss(&vnode->fid, need_clear);
649 write_sequnlock(&vnode->cb_lock);
650 valid = false;
651 }
652
653 return valid;
654 }
655
656 /*
657 * validate a vnode/inode
658 * - there are several things we need to check
659 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
660 * symlink)
661 * - parent dir metadata changed (security changes)
662 * - dentry data changed (write, truncate)
663 * - dentry metadata changed (security changes)
664 */
afs_validate(struct afs_vnode * vnode,struct key * key)665 int afs_validate(struct afs_vnode *vnode, struct key *key)
666 {
667 bool valid;
668 int ret;
669
670 _enter("{v={%llx:%llu} fl=%lx},%x",
671 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
672 key_serial(key));
673
674 rcu_read_lock();
675 valid = afs_check_validity(vnode);
676 rcu_read_unlock();
677
678 if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
679 clear_nlink(&vnode->vfs_inode);
680
681 if (valid)
682 goto valid;
683
684 down_write(&vnode->validate_lock);
685
686 /* if the promise has expired, we need to check the server again to get
687 * a new promise - note that if the (parent) directory's metadata was
688 * changed then the security may be different and we may no longer have
689 * access */
690 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
691 _debug("not promised");
692 ret = afs_fetch_status(vnode, key, false, NULL);
693 if (ret < 0) {
694 if (ret == -ENOENT) {
695 set_bit(AFS_VNODE_DELETED, &vnode->flags);
696 ret = -ESTALE;
697 }
698 goto error_unlock;
699 }
700 _debug("new promise [fl=%lx]", vnode->flags);
701 }
702
703 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
704 _debug("file already deleted");
705 ret = -ESTALE;
706 goto error_unlock;
707 }
708
709 /* if the vnode's data version number changed then its contents are
710 * different */
711 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
712 afs_zap_data(vnode);
713 up_write(&vnode->validate_lock);
714 valid:
715 _leave(" = 0");
716 return 0;
717
718 error_unlock:
719 up_write(&vnode->validate_lock);
720 _leave(" = %d", ret);
721 return ret;
722 }
723
724 /*
725 * read the attributes of an inode
726 */
afs_getattr(const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)727 int afs_getattr(const struct path *path, struct kstat *stat,
728 u32 request_mask, unsigned int query_flags)
729 {
730 struct inode *inode = d_inode(path->dentry);
731 struct afs_vnode *vnode = AFS_FS_I(inode);
732 struct key *key;
733 int ret, seq = 0;
734
735 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
736
737 if (vnode->volume &&
738 !(query_flags & AT_STATX_DONT_SYNC) &&
739 !test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
740 key = afs_request_key(vnode->volume->cell);
741 if (IS_ERR(key))
742 return PTR_ERR(key);
743 ret = afs_validate(vnode, key);
744 key_put(key);
745 if (ret < 0)
746 return ret;
747 }
748
749 do {
750 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
751 generic_fillattr(inode, stat);
752 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
753 stat->nlink > 0)
754 stat->nlink -= 1;
755 } while (need_seqretry(&vnode->cb_lock, seq));
756
757 done_seqretry(&vnode->cb_lock, seq);
758 return 0;
759 }
760
761 /*
762 * discard an AFS inode
763 */
afs_drop_inode(struct inode * inode)764 int afs_drop_inode(struct inode *inode)
765 {
766 _enter("");
767
768 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
769 return generic_delete_inode(inode);
770 else
771 return generic_drop_inode(inode);
772 }
773
774 /*
775 * clear an AFS inode
776 */
afs_evict_inode(struct inode * inode)777 void afs_evict_inode(struct inode *inode)
778 {
779 struct afs_vnode *vnode;
780
781 vnode = AFS_FS_I(inode);
782
783 _enter("{%llx:%llu.%d}",
784 vnode->fid.vid,
785 vnode->fid.vnode,
786 vnode->fid.unique);
787
788 _debug("CLEAR INODE %p", inode);
789
790 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
791
792 truncate_inode_pages_final(&inode->i_data);
793 clear_inode(inode);
794
795 while (!list_empty(&vnode->wb_keys)) {
796 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
797 struct afs_wb_key, vnode_link);
798 list_del(&wbk->vnode_link);
799 afs_put_wb_key(wbk);
800 }
801
802 #ifdef CONFIG_AFS_FSCACHE
803 {
804 struct afs_vnode_cache_aux aux;
805
806 aux.data_version = vnode->status.data_version;
807 fscache_relinquish_cookie(vnode->cache, &aux,
808 test_bit(AFS_VNODE_DELETED, &vnode->flags));
809 vnode->cache = NULL;
810 }
811 #endif
812
813 afs_prune_wb_keys(vnode);
814 afs_put_permits(rcu_access_pointer(vnode->permit_cache));
815 key_put(vnode->silly_key);
816 vnode->silly_key = NULL;
817 key_put(vnode->lock_key);
818 vnode->lock_key = NULL;
819 _leave("");
820 }
821
afs_setattr_success(struct afs_operation * op)822 static void afs_setattr_success(struct afs_operation *op)
823 {
824 struct afs_vnode_param *vp = &op->file[0];
825 struct inode *inode = &vp->vnode->vfs_inode;
826 loff_t old_i_size = i_size_read(inode);
827
828 op->setattr.old_i_size = old_i_size;
829 afs_vnode_commit_status(op, vp);
830 /* inode->i_size has now been changed. */
831
832 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
833 loff_t size = op->setattr.attr->ia_size;
834 if (size > old_i_size)
835 pagecache_isize_extended(inode, old_i_size, size);
836 }
837 }
838
afs_setattr_edit_file(struct afs_operation * op)839 static void afs_setattr_edit_file(struct afs_operation *op)
840 {
841 struct afs_vnode_param *vp = &op->file[0];
842 struct inode *inode = &vp->vnode->vfs_inode;
843
844 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
845 loff_t size = op->setattr.attr->ia_size;
846 loff_t i_size = op->setattr.old_i_size;
847
848 if (size < i_size)
849 truncate_pagecache(inode, size);
850 }
851 }
852
853 static const struct afs_operation_ops afs_setattr_operation = {
854 .issue_afs_rpc = afs_fs_setattr,
855 .issue_yfs_rpc = yfs_fs_setattr,
856 .success = afs_setattr_success,
857 .edit_dir = afs_setattr_edit_file,
858 };
859
860 /*
861 * set the attributes of an inode
862 */
afs_setattr(struct dentry * dentry,struct iattr * attr)863 int afs_setattr(struct dentry *dentry, struct iattr *attr)
864 {
865 struct afs_operation *op;
866 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
867 int ret;
868
869 _enter("{%llx:%llu},{n=%pd},%x",
870 vnode->fid.vid, vnode->fid.vnode, dentry,
871 attr->ia_valid);
872
873 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
874 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET |
875 ATTR_TOUCH))) {
876 _leave(" = 0 [unsupported]");
877 return 0;
878 }
879
880 if (attr->ia_valid & ATTR_SIZE) {
881 if (!S_ISREG(vnode->vfs_inode.i_mode))
882 return -EISDIR;
883
884 ret = inode_newsize_ok(&vnode->vfs_inode, attr->ia_size);
885 if (ret)
886 return ret;
887
888 if (attr->ia_size == i_size_read(&vnode->vfs_inode))
889 attr->ia_valid &= ~ATTR_SIZE;
890 }
891
892 /* flush any dirty data outstanding on a regular file */
893 if (S_ISREG(vnode->vfs_inode.i_mode))
894 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
895
896 /* Prevent any new writebacks from starting whilst we do this. */
897 down_write(&vnode->validate_lock);
898
899 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
900 afs_file_key(attr->ia_file) : NULL),
901 vnode->volume);
902 if (IS_ERR(op)) {
903 ret = PTR_ERR(op);
904 goto out_unlock;
905 }
906
907 afs_op_set_vnode(op, 0, vnode);
908 op->setattr.attr = attr;
909
910 if (attr->ia_valid & ATTR_SIZE) {
911 op->file[0].dv_delta = 1;
912 op->file[0].set_size = true;
913 }
914 op->ctime = attr->ia_ctime;
915 op->file[0].update_ctime = 1;
916 op->file[0].modification = true;
917
918 op->ops = &afs_setattr_operation;
919 ret = afs_do_sync_operation(op);
920
921 out_unlock:
922 up_write(&vnode->validate_lock);
923 _leave(" = %d", ret);
924 return ret;
925 }
926