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 .listxattr = afs_listxattr,
31 };
32
dump_vnode(struct afs_vnode * vnode,struct afs_vnode * parent_vnode)33 static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
34 {
35 static unsigned long once_only;
36
37 pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);
38 pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
39 vnode->status.abort_code,
40 vnode->status.mode,
41 vnode->status.size,
42 vnode->status.data_version);
43 pr_warn("kAFS: vnode %llx:%llx:%x\n",
44 vnode->fid.vid,
45 vnode->fid.vnode,
46 vnode->fid.unique);
47 if (parent_vnode)
48 pr_warn("kAFS: dir %llx:%llx:%x\n",
49 parent_vnode->fid.vid,
50 parent_vnode->fid.vnode,
51 parent_vnode->fid.unique);
52
53 if (!test_and_set_bit(0, &once_only))
54 dump_stack();
55 }
56
57 /*
58 * Set the file size and block count. Estimate the number of 512 bytes blocks
59 * used, rounded up to nearest 1K for consistency with other AFS clients.
60 */
afs_set_i_size(struct afs_vnode * vnode,u64 size)61 static void afs_set_i_size(struct afs_vnode *vnode, u64 size)
62 {
63 i_size_write(&vnode->vfs_inode, size);
64 vnode->vfs_inode.i_blocks = ((size + 1023) >> 10) << 1;
65 }
66
67 /*
68 * Initialise an inode from the vnode status.
69 */
afs_inode_init_from_status(struct afs_operation * op,struct afs_vnode_param * vp,struct afs_vnode * vnode)70 static int afs_inode_init_from_status(struct afs_operation *op,
71 struct afs_vnode_param *vp,
72 struct afs_vnode *vnode)
73 {
74 struct afs_file_status *status = &vp->scb.status;
75 struct inode *inode = AFS_VNODE_TO_I(vnode);
76 struct timespec64 t;
77
78 _enter("{%llx:%llu.%u} %s",
79 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
80 op->type ? op->type->name : "???");
81
82 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
83 status->type,
84 status->nlink,
85 (unsigned long long) status->size,
86 status->data_version,
87 status->mode);
88
89 write_seqlock(&vnode->cb_lock);
90
91 vnode->cb_v_break = op->cb_v_break;
92 vnode->cb_s_break = op->cb_s_break;
93 vnode->status = *status;
94
95 t = status->mtime_client;
96 inode->i_ctime = t;
97 inode->i_mtime = t;
98 inode->i_atime = t;
99 inode->i_flags |= S_NOATIME;
100 inode->i_uid = make_kuid(&init_user_ns, status->owner);
101 inode->i_gid = make_kgid(&init_user_ns, status->group);
102 set_nlink(&vnode->vfs_inode, status->nlink);
103
104 switch (status->type) {
105 case AFS_FTYPE_FILE:
106 inode->i_mode = S_IFREG | status->mode;
107 inode->i_op = &afs_file_inode_operations;
108 inode->i_fop = &afs_file_operations;
109 inode->i_mapping->a_ops = &afs_fs_aops;
110 break;
111 case AFS_FTYPE_DIR:
112 inode->i_mode = S_IFDIR | status->mode;
113 inode->i_op = &afs_dir_inode_operations;
114 inode->i_fop = &afs_dir_file_operations;
115 inode->i_mapping->a_ops = &afs_dir_aops;
116 break;
117 case AFS_FTYPE_SYMLINK:
118 /* Symlinks with a mode of 0644 are actually mountpoints. */
119 if ((status->mode & 0777) == 0644) {
120 inode->i_flags |= S_AUTOMOUNT;
121
122 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
123
124 inode->i_mode = S_IFDIR | 0555;
125 inode->i_op = &afs_mntpt_inode_operations;
126 inode->i_fop = &afs_mntpt_file_operations;
127 inode->i_mapping->a_ops = &afs_fs_aops;
128 } else {
129 inode->i_mode = S_IFLNK | status->mode;
130 inode->i_op = &afs_symlink_inode_operations;
131 inode->i_mapping->a_ops = &afs_fs_aops;
132 }
133 inode_nohighmem(inode);
134 break;
135 default:
136 dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
137 write_sequnlock(&vnode->cb_lock);
138 return afs_protocol_error(NULL, afs_eproto_file_type);
139 }
140
141 afs_set_i_size(vnode, status->size);
142
143 vnode->invalid_before = status->data_version;
144 inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
145
146 if (!vp->scb.have_cb) {
147 /* it's a symlink we just created (the fileserver
148 * didn't give us a callback) */
149 vnode->cb_expires_at = ktime_get_real_seconds();
150 } else {
151 vnode->cb_expires_at = vp->scb.callback.expires_at;
152 vnode->cb_server = op->server;
153 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
154 }
155
156 write_sequnlock(&vnode->cb_lock);
157 return 0;
158 }
159
160 /*
161 * Update the core inode struct from a returned status record.
162 */
afs_apply_status(struct afs_operation * op,struct afs_vnode_param * vp)163 static void afs_apply_status(struct afs_operation *op,
164 struct afs_vnode_param *vp)
165 {
166 struct afs_file_status *status = &vp->scb.status;
167 struct afs_vnode *vnode = vp->vnode;
168 struct inode *inode = &vnode->vfs_inode;
169 struct timespec64 t;
170 umode_t mode;
171 bool data_changed = false;
172 bool change_size = vp->set_size;
173
174 _enter("{%llx:%llu.%u} %s",
175 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
176 op->type ? op->type->name : "???");
177
178 BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
179
180 if (status->type != vnode->status.type) {
181 pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",
182 vnode->fid.vid,
183 vnode->fid.vnode,
184 vnode->fid.unique,
185 status->type, vnode->status.type);
186 afs_protocol_error(NULL, afs_eproto_bad_status);
187 return;
188 }
189
190 if (status->nlink != vnode->status.nlink)
191 set_nlink(inode, status->nlink);
192
193 if (status->owner != vnode->status.owner)
194 inode->i_uid = make_kuid(&init_user_ns, status->owner);
195
196 if (status->group != vnode->status.group)
197 inode->i_gid = make_kgid(&init_user_ns, status->group);
198
199 if (status->mode != vnode->status.mode) {
200 mode = inode->i_mode;
201 mode &= ~S_IALLUGO;
202 mode |= status->mode;
203 WRITE_ONCE(inode->i_mode, mode);
204 }
205
206 t = status->mtime_client;
207 inode->i_mtime = t;
208 if (vp->update_ctime)
209 inode->i_ctime = op->ctime;
210
211 if (vnode->status.data_version != status->data_version)
212 data_changed = true;
213
214 vnode->status = *status;
215
216 if (vp->dv_before + vp->dv_delta != status->data_version) {
217 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags))
218 pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s\n",
219 vnode->fid.vid, vnode->fid.vnode,
220 (unsigned long long)vp->dv_before + vp->dv_delta,
221 (unsigned long long)status->data_version,
222 op->type ? op->type->name : "???");
223
224 vnode->invalid_before = status->data_version;
225 if (vnode->status.type == AFS_FTYPE_DIR) {
226 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
227 afs_stat_v(vnode, n_inval);
228 } else {
229 set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
230 }
231 change_size = true;
232 } else if (vnode->status.type == AFS_FTYPE_DIR) {
233 /* Expected directory change is handled elsewhere so
234 * that we can locally edit the directory and save on a
235 * download.
236 */
237 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
238 data_changed = false;
239 change_size = true;
240 }
241
242 if (data_changed) {
243 inode_set_iversion_raw(inode, status->data_version);
244
245 /* Only update the size if the data version jumped. If the
246 * file is being modified locally, then we might have our own
247 * idea of what the size should be that's not the same as
248 * what's on the server.
249 */
250 if (change_size) {
251 afs_set_i_size(vnode, status->size);
252 inode->i_ctime = t;
253 inode->i_atime = t;
254 }
255 }
256 }
257
258 /*
259 * Apply a callback to a vnode.
260 */
afs_apply_callback(struct afs_operation * op,struct afs_vnode_param * vp)261 static void afs_apply_callback(struct afs_operation *op,
262 struct afs_vnode_param *vp)
263 {
264 struct afs_callback *cb = &vp->scb.callback;
265 struct afs_vnode *vnode = vp->vnode;
266
267 if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
268 vnode->cb_expires_at = cb->expires_at;
269 vnode->cb_server = op->server;
270 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
271 }
272 }
273
274 /*
275 * Apply the received status and callback to an inode all in the same critical
276 * section to avoid races with afs_validate().
277 */
afs_vnode_commit_status(struct afs_operation * op,struct afs_vnode_param * vp)278 void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
279 {
280 struct afs_vnode *vnode = vp->vnode;
281
282 _enter("");
283
284 write_seqlock(&vnode->cb_lock);
285
286 if (vp->scb.have_error) {
287 /* A YFS server will return this from RemoveFile2 and AFS and
288 * YFS will return this from InlineBulkStatus.
289 */
290 if (vp->scb.status.abort_code == VNOVNODE) {
291 set_bit(AFS_VNODE_DELETED, &vnode->flags);
292 clear_nlink(&vnode->vfs_inode);
293 __afs_break_callback(vnode, afs_cb_break_for_deleted);
294 op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
295 }
296 } else if (vp->scb.have_status) {
297 if (vp->dv_before + vp->dv_delta != vp->scb.status.data_version &&
298 vp->speculative)
299 /* Ignore the result of a speculative bulk status fetch
300 * if it splits around a modification op, thereby
301 * appearing to regress the data version.
302 */
303 goto out;
304 afs_apply_status(op, vp);
305 if (vp->scb.have_cb)
306 afs_apply_callback(op, vp);
307 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
308 drop_nlink(&vnode->vfs_inode);
309 if (vnode->vfs_inode.i_nlink == 0) {
310 set_bit(AFS_VNODE_DELETED, &vnode->flags);
311 __afs_break_callback(vnode, afs_cb_break_for_deleted);
312 }
313 }
314
315 out:
316 write_sequnlock(&vnode->cb_lock);
317
318 if (vp->scb.have_status)
319 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
320 }
321
afs_fetch_status_success(struct afs_operation * op)322 static void afs_fetch_status_success(struct afs_operation *op)
323 {
324 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
325 struct afs_vnode *vnode = vp->vnode;
326 int ret;
327
328 if (vnode->vfs_inode.i_state & I_NEW) {
329 ret = afs_inode_init_from_status(op, vp, vnode);
330 op->error = ret;
331 if (ret == 0)
332 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
333 } else {
334 afs_vnode_commit_status(op, vp);
335 }
336 }
337
338 const struct afs_operation_ops afs_fetch_status_operation = {
339 .issue_afs_rpc = afs_fs_fetch_status,
340 .issue_yfs_rpc = yfs_fs_fetch_status,
341 .success = afs_fetch_status_success,
342 .aborted = afs_check_for_remote_deletion,
343 };
344
345 /*
346 * Fetch file status from the volume.
347 */
afs_fetch_status(struct afs_vnode * vnode,struct key * key,bool is_new,afs_access_t * _caller_access)348 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
349 afs_access_t *_caller_access)
350 {
351 struct afs_operation *op;
352
353 _enter("%s,{%llx:%llu.%u,S=%lx}",
354 vnode->volume->name,
355 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
356 vnode->flags);
357
358 op = afs_alloc_operation(key, vnode->volume);
359 if (IS_ERR(op))
360 return PTR_ERR(op);
361
362 afs_op_set_vnode(op, 0, vnode);
363
364 op->nr_files = 1;
365 op->ops = &afs_fetch_status_operation;
366 afs_begin_vnode_operation(op);
367 afs_wait_for_operation(op);
368
369 if (_caller_access)
370 *_caller_access = op->file[0].scb.status.caller_access;
371 return afs_put_operation(op);
372 }
373
374 /*
375 * ilookup() comparator
376 */
afs_ilookup5_test_by_fid(struct inode * inode,void * opaque)377 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
378 {
379 struct afs_vnode *vnode = AFS_FS_I(inode);
380 struct afs_fid *fid = opaque;
381
382 return (fid->vnode == vnode->fid.vnode &&
383 fid->vnode_hi == vnode->fid.vnode_hi &&
384 fid->unique == vnode->fid.unique);
385 }
386
387 /*
388 * iget5() comparator
389 */
afs_iget5_test(struct inode * inode,void * opaque)390 static int afs_iget5_test(struct inode *inode, void *opaque)
391 {
392 struct afs_vnode_param *vp = opaque;
393 //struct afs_vnode *vnode = AFS_FS_I(inode);
394
395 return afs_ilookup5_test_by_fid(inode, &vp->fid);
396 }
397
398 /*
399 * iget5() inode initialiser
400 */
afs_iget5_set(struct inode * inode,void * opaque)401 static int afs_iget5_set(struct inode *inode, void *opaque)
402 {
403 struct afs_vnode_param *vp = opaque;
404 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
405 struct afs_vnode *vnode = AFS_FS_I(inode);
406
407 vnode->volume = as->volume;
408 vnode->fid = vp->fid;
409
410 /* YFS supports 96-bit vnode IDs, but Linux only supports
411 * 64-bit inode numbers.
412 */
413 inode->i_ino = vnode->fid.vnode;
414 inode->i_generation = vnode->fid.unique;
415 return 0;
416 }
417
418 /*
419 * Get a cache cookie for an inode.
420 */
afs_get_inode_cache(struct afs_vnode * vnode)421 static void afs_get_inode_cache(struct afs_vnode *vnode)
422 {
423 #ifdef CONFIG_AFS_FSCACHE
424 struct {
425 u32 vnode_id;
426 u32 unique;
427 u32 vnode_id_ext[2]; /* Allow for a 96-bit key */
428 } __packed key;
429 struct afs_vnode_cache_aux aux;
430
431 if (vnode->status.type == AFS_FTYPE_DIR) {
432 vnode->cache = NULL;
433 return;
434 }
435
436 key.vnode_id = vnode->fid.vnode;
437 key.unique = vnode->fid.unique;
438 key.vnode_id_ext[0] = vnode->fid.vnode >> 32;
439 key.vnode_id_ext[1] = vnode->fid.vnode_hi;
440 aux.data_version = vnode->status.data_version;
441
442 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
443 &afs_vnode_cache_index_def,
444 &key, sizeof(key),
445 &aux, sizeof(aux),
446 vnode, vnode->status.size, true);
447 #endif
448 }
449
450 /*
451 * inode retrieval
452 */
afs_iget(struct afs_operation * op,struct afs_vnode_param * vp)453 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
454 {
455 struct afs_vnode_param *dvp = &op->file[0];
456 struct super_block *sb = dvp->vnode->vfs_inode.i_sb;
457 struct afs_vnode *vnode;
458 struct inode *inode;
459 int ret;
460
461 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
462
463 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
464 if (!inode) {
465 _leave(" = -ENOMEM");
466 return ERR_PTR(-ENOMEM);
467 }
468
469 vnode = AFS_FS_I(inode);
470
471 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
472 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
473
474 /* deal with an existing inode */
475 if (!(inode->i_state & I_NEW)) {
476 _leave(" = %p", inode);
477 return inode;
478 }
479
480 ret = afs_inode_init_from_status(op, vp, vnode);
481 if (ret < 0)
482 goto bad_inode;
483
484 afs_get_inode_cache(vnode);
485
486 /* success */
487 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
488 unlock_new_inode(inode);
489 _leave(" = %p", inode);
490 return inode;
491
492 /* failure */
493 bad_inode:
494 iget_failed(inode);
495 _leave(" = %d [bad]", ret);
496 return ERR_PTR(ret);
497 }
498
afs_iget5_set_root(struct inode * inode,void * opaque)499 static int afs_iget5_set_root(struct inode *inode, void *opaque)
500 {
501 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
502 struct afs_vnode *vnode = AFS_FS_I(inode);
503
504 vnode->volume = as->volume;
505 vnode->fid.vid = as->volume->vid,
506 vnode->fid.vnode = 1;
507 vnode->fid.unique = 1;
508 inode->i_ino = 1;
509 inode->i_generation = 1;
510 return 0;
511 }
512
513 /*
514 * Set up the root inode for a volume. This is always vnode 1, unique 1 within
515 * the volume.
516 */
afs_root_iget(struct super_block * sb,struct key * key)517 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
518 {
519 struct afs_super_info *as = AFS_FS_S(sb);
520 struct afs_operation *op;
521 struct afs_vnode *vnode;
522 struct inode *inode;
523 int ret;
524
525 _enter(",{%llx},,", as->volume->vid);
526
527 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
528 if (!inode) {
529 _leave(" = -ENOMEM");
530 return ERR_PTR(-ENOMEM);
531 }
532
533 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
534
535 BUG_ON(!(inode->i_state & I_NEW));
536
537 vnode = AFS_FS_I(inode);
538 vnode->cb_v_break = as->volume->cb_v_break,
539
540 op = afs_alloc_operation(key, as->volume);
541 if (IS_ERR(op)) {
542 ret = PTR_ERR(op);
543 goto error;
544 }
545
546 afs_op_set_vnode(op, 0, vnode);
547
548 op->nr_files = 1;
549 op->ops = &afs_fetch_status_operation;
550 ret = afs_do_sync_operation(op);
551 if (ret < 0)
552 goto error;
553
554 afs_get_inode_cache(vnode);
555
556 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
557 unlock_new_inode(inode);
558 _leave(" = %p", inode);
559 return inode;
560
561 error:
562 iget_failed(inode);
563 _leave(" = %d [bad]", ret);
564 return ERR_PTR(ret);
565 }
566
567 /*
568 * mark the data attached to an inode as obsolete due to a write on the server
569 * - might also want to ditch all the outstanding writes and dirty pages
570 */
afs_zap_data(struct afs_vnode * vnode)571 static void afs_zap_data(struct afs_vnode *vnode)
572 {
573 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
574
575 #ifdef CONFIG_AFS_FSCACHE
576 fscache_invalidate(vnode->cache);
577 #endif
578
579 /* nuke all the non-dirty pages that aren't locked, mapped or being
580 * written back in a regular file and completely discard the pages in a
581 * directory or symlink */
582 if (S_ISREG(vnode->vfs_inode.i_mode))
583 invalidate_remote_inode(&vnode->vfs_inode);
584 else
585 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
586 }
587
588 /*
589 * Get the server reinit counter for a vnode's current server.
590 */
afs_get_s_break_rcu(struct afs_vnode * vnode,unsigned int * _s_break)591 static bool afs_get_s_break_rcu(struct afs_vnode *vnode, unsigned int *_s_break)
592 {
593 struct afs_server_list *slist = rcu_dereference(vnode->volume->servers);
594 struct afs_server *server;
595 int i;
596
597 for (i = 0; i < slist->nr_servers; i++) {
598 server = slist->servers[i].server;
599 if (server == vnode->cb_server) {
600 *_s_break = READ_ONCE(server->cb_s_break);
601 return true;
602 }
603 }
604
605 return false;
606 }
607
608 /*
609 * Check the validity of a vnode/inode.
610 */
afs_check_validity(struct afs_vnode * vnode)611 bool afs_check_validity(struct afs_vnode *vnode)
612 {
613 struct afs_volume *volume = vnode->volume;
614 enum afs_cb_break_reason need_clear = afs_cb_break_no_break;
615 time64_t now = ktime_get_real_seconds();
616 bool valid;
617 unsigned int cb_break, cb_s_break, cb_v_break;
618 int seq = 0;
619
620 do {
621 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
622 cb_v_break = READ_ONCE(volume->cb_v_break);
623 cb_break = vnode->cb_break;
624
625 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&
626 afs_get_s_break_rcu(vnode, &cb_s_break)) {
627 if (vnode->cb_s_break != cb_s_break ||
628 vnode->cb_v_break != cb_v_break) {
629 vnode->cb_s_break = cb_s_break;
630 vnode->cb_v_break = cb_v_break;
631 need_clear = afs_cb_break_for_vsbreak;
632 valid = false;
633 } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
634 need_clear = afs_cb_break_for_zap;
635 valid = false;
636 } else if (vnode->cb_expires_at - 10 <= now) {
637 need_clear = afs_cb_break_for_lapsed;
638 valid = false;
639 } else {
640 valid = true;
641 }
642 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
643 valid = true;
644 } else {
645 vnode->cb_v_break = cb_v_break;
646 valid = false;
647 }
648
649 } while (need_seqretry(&vnode->cb_lock, seq));
650
651 done_seqretry(&vnode->cb_lock, seq);
652
653 if (need_clear != afs_cb_break_no_break) {
654 write_seqlock(&vnode->cb_lock);
655 if (cb_break == vnode->cb_break)
656 __afs_break_callback(vnode, need_clear);
657 else
658 trace_afs_cb_miss(&vnode->fid, need_clear);
659 write_sequnlock(&vnode->cb_lock);
660 valid = false;
661 }
662
663 return valid;
664 }
665
666 /*
667 * validate a vnode/inode
668 * - there are several things we need to check
669 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
670 * symlink)
671 * - parent dir metadata changed (security changes)
672 * - dentry data changed (write, truncate)
673 * - dentry metadata changed (security changes)
674 */
afs_validate(struct afs_vnode * vnode,struct key * key)675 int afs_validate(struct afs_vnode *vnode, struct key *key)
676 {
677 bool valid;
678 int ret;
679
680 _enter("{v={%llx:%llu} fl=%lx},%x",
681 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
682 key_serial(key));
683
684 rcu_read_lock();
685 valid = afs_check_validity(vnode);
686 rcu_read_unlock();
687
688 if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
689 clear_nlink(&vnode->vfs_inode);
690
691 if (valid)
692 goto valid;
693
694 down_write(&vnode->validate_lock);
695
696 /* if the promise has expired, we need to check the server again to get
697 * a new promise - note that if the (parent) directory's metadata was
698 * changed then the security may be different and we may no longer have
699 * access */
700 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
701 _debug("not promised");
702 ret = afs_fetch_status(vnode, key, false, NULL);
703 if (ret < 0) {
704 if (ret == -ENOENT) {
705 set_bit(AFS_VNODE_DELETED, &vnode->flags);
706 ret = -ESTALE;
707 }
708 goto error_unlock;
709 }
710 _debug("new promise [fl=%lx]", vnode->flags);
711 }
712
713 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
714 _debug("file already deleted");
715 ret = -ESTALE;
716 goto error_unlock;
717 }
718
719 /* if the vnode's data version number changed then its contents are
720 * different */
721 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
722 afs_zap_data(vnode);
723 up_write(&vnode->validate_lock);
724 valid:
725 _leave(" = 0");
726 return 0;
727
728 error_unlock:
729 up_write(&vnode->validate_lock);
730 _leave(" = %d", ret);
731 return ret;
732 }
733
734 /*
735 * read the attributes of an inode
736 */
afs_getattr(const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)737 int afs_getattr(const struct path *path, struct kstat *stat,
738 u32 request_mask, unsigned int query_flags)
739 {
740 struct inode *inode = d_inode(path->dentry);
741 struct afs_vnode *vnode = AFS_FS_I(inode);
742 int seq = 0;
743
744 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
745
746 do {
747 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
748 generic_fillattr(inode, stat);
749 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
750 stat->nlink > 0)
751 stat->nlink -= 1;
752 } while (need_seqretry(&vnode->cb_lock, seq));
753
754 done_seqretry(&vnode->cb_lock, seq);
755 return 0;
756 }
757
758 /*
759 * discard an AFS inode
760 */
afs_drop_inode(struct inode * inode)761 int afs_drop_inode(struct inode *inode)
762 {
763 _enter("");
764
765 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
766 return generic_delete_inode(inode);
767 else
768 return generic_drop_inode(inode);
769 }
770
771 /*
772 * clear an AFS inode
773 */
afs_evict_inode(struct inode * inode)774 void afs_evict_inode(struct inode *inode)
775 {
776 struct afs_vnode *vnode;
777
778 vnode = AFS_FS_I(inode);
779
780 _enter("{%llx:%llu.%d}",
781 vnode->fid.vid,
782 vnode->fid.vnode,
783 vnode->fid.unique);
784
785 _debug("CLEAR INODE %p", inode);
786
787 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
788
789 truncate_inode_pages_final(&inode->i_data);
790 clear_inode(inode);
791
792 while (!list_empty(&vnode->wb_keys)) {
793 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
794 struct afs_wb_key, vnode_link);
795 list_del(&wbk->vnode_link);
796 afs_put_wb_key(wbk);
797 }
798
799 #ifdef CONFIG_AFS_FSCACHE
800 {
801 struct afs_vnode_cache_aux aux;
802
803 aux.data_version = vnode->status.data_version;
804 fscache_relinquish_cookie(vnode->cache, &aux,
805 test_bit(AFS_VNODE_DELETED, &vnode->flags));
806 vnode->cache = NULL;
807 }
808 #endif
809
810 afs_prune_wb_keys(vnode);
811 afs_put_permits(rcu_access_pointer(vnode->permit_cache));
812 key_put(vnode->silly_key);
813 vnode->silly_key = NULL;
814 key_put(vnode->lock_key);
815 vnode->lock_key = NULL;
816 _leave("");
817 }
818
afs_setattr_success(struct afs_operation * op)819 static void afs_setattr_success(struct afs_operation *op)
820 {
821 struct afs_vnode_param *vp = &op->file[0];
822 struct inode *inode = &vp->vnode->vfs_inode;
823 loff_t old_i_size = i_size_read(inode);
824
825 op->setattr.old_i_size = old_i_size;
826 afs_vnode_commit_status(op, vp);
827 /* inode->i_size has now been changed. */
828
829 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
830 loff_t size = op->setattr.attr->ia_size;
831 if (size > old_i_size)
832 pagecache_isize_extended(inode, old_i_size, size);
833 }
834 }
835
afs_setattr_edit_file(struct afs_operation * op)836 static void afs_setattr_edit_file(struct afs_operation *op)
837 {
838 struct afs_vnode_param *vp = &op->file[0];
839 struct inode *inode = &vp->vnode->vfs_inode;
840
841 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
842 loff_t size = op->setattr.attr->ia_size;
843 loff_t i_size = op->setattr.old_i_size;
844
845 if (size < i_size)
846 truncate_pagecache(inode, size);
847 }
848 }
849
850 static const struct afs_operation_ops afs_setattr_operation = {
851 .issue_afs_rpc = afs_fs_setattr,
852 .issue_yfs_rpc = yfs_fs_setattr,
853 .success = afs_setattr_success,
854 .edit_dir = afs_setattr_edit_file,
855 };
856
857 /*
858 * set the attributes of an inode
859 */
afs_setattr(struct dentry * dentry,struct iattr * attr)860 int afs_setattr(struct dentry *dentry, struct iattr *attr)
861 {
862 struct afs_operation *op;
863 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
864 int ret;
865
866 _enter("{%llx:%llu},{n=%pd},%x",
867 vnode->fid.vid, vnode->fid.vnode, dentry,
868 attr->ia_valid);
869
870 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
871 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET |
872 ATTR_TOUCH))) {
873 _leave(" = 0 [unsupported]");
874 return 0;
875 }
876
877 if (attr->ia_valid & ATTR_SIZE) {
878 if (!S_ISREG(vnode->vfs_inode.i_mode))
879 return -EISDIR;
880
881 ret = inode_newsize_ok(&vnode->vfs_inode, attr->ia_size);
882 if (ret)
883 return ret;
884
885 if (attr->ia_size == i_size_read(&vnode->vfs_inode))
886 attr->ia_valid &= ~ATTR_SIZE;
887 }
888
889 /* flush any dirty data outstanding on a regular file */
890 if (S_ISREG(vnode->vfs_inode.i_mode))
891 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
892
893 /* Prevent any new writebacks from starting whilst we do this. */
894 down_write(&vnode->validate_lock);
895
896 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
897 afs_file_key(attr->ia_file) : NULL),
898 vnode->volume);
899 if (IS_ERR(op)) {
900 ret = PTR_ERR(op);
901 goto out_unlock;
902 }
903
904 afs_op_set_vnode(op, 0, vnode);
905 op->setattr.attr = attr;
906
907 if (attr->ia_valid & ATTR_SIZE) {
908 op->file[0].dv_delta = 1;
909 op->file[0].set_size = true;
910 }
911 op->ctime = attr->ia_ctime;
912 op->file[0].update_ctime = 1;
913
914 op->ops = &afs_setattr_operation;
915 ret = afs_do_sync_operation(op);
916
917 out_unlock:
918 up_write(&vnode->validate_lock);
919 _leave(" = %d", ret);
920 return ret;
921 }
922
