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 * Set parameters for the netfs library
58 */
afs_set_netfs_context(struct afs_vnode * vnode)59 static void afs_set_netfs_context(struct afs_vnode *vnode)
60 {
61 netfs_inode_init(&vnode->netfs, &afs_req_ops);
62 }
63
64 /*
65 * Initialise an inode from the vnode status.
66 */
afs_inode_init_from_status(struct afs_operation * op,struct afs_vnode_param * vp,struct afs_vnode * vnode)67 static int afs_inode_init_from_status(struct afs_operation *op,
68 struct afs_vnode_param *vp,
69 struct afs_vnode *vnode)
70 {
71 struct afs_file_status *status = &vp->scb.status;
72 struct inode *inode = AFS_VNODE_TO_I(vnode);
73 struct timespec64 t;
74
75 _enter("{%llx:%llu.%u} %s",
76 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
77 op->type ? op->type->name : "???");
78
79 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
80 status->type,
81 status->nlink,
82 (unsigned long long) status->size,
83 status->data_version,
84 status->mode);
85
86 write_seqlock(&vnode->cb_lock);
87
88 vnode->cb_v_break = op->cb_v_break;
89 vnode->cb_s_break = op->cb_s_break;
90 vnode->status = *status;
91
92 t = status->mtime_client;
93 inode->i_ctime = t;
94 inode->i_mtime = t;
95 inode->i_atime = t;
96 inode->i_flags |= S_NOATIME;
97 inode->i_uid = make_kuid(&init_user_ns, status->owner);
98 inode->i_gid = make_kgid(&init_user_ns, status->group);
99 set_nlink(&vnode->netfs.inode, status->nlink);
100
101 switch (status->type) {
102 case AFS_FTYPE_FILE:
103 inode->i_mode = S_IFREG | (status->mode & S_IALLUGO);
104 inode->i_op = &afs_file_inode_operations;
105 inode->i_fop = &afs_file_operations;
106 inode->i_mapping->a_ops = &afs_file_aops;
107 mapping_set_large_folios(inode->i_mapping);
108 break;
109 case AFS_FTYPE_DIR:
110 inode->i_mode = S_IFDIR | (status->mode & S_IALLUGO);
111 inode->i_op = &afs_dir_inode_operations;
112 inode->i_fop = &afs_dir_file_operations;
113 inode->i_mapping->a_ops = &afs_dir_aops;
114 mapping_set_large_folios(inode->i_mapping);
115 break;
116 case AFS_FTYPE_SYMLINK:
117 /* Symlinks with a mode of 0644 are actually mountpoints. */
118 if ((status->mode & 0777) == 0644) {
119 inode->i_flags |= S_AUTOMOUNT;
120
121 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
122
123 inode->i_mode = S_IFDIR | 0555;
124 inode->i_op = &afs_mntpt_inode_operations;
125 inode->i_fop = &afs_mntpt_file_operations;
126 inode->i_mapping->a_ops = &afs_symlink_aops;
127 } else {
128 inode->i_mode = S_IFLNK | status->mode;
129 inode->i_op = &afs_symlink_inode_operations;
130 inode->i_mapping->a_ops = &afs_symlink_aops;
131 }
132 inode_nohighmem(inode);
133 break;
134 default:
135 dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
136 write_sequnlock(&vnode->cb_lock);
137 return afs_protocol_error(NULL, afs_eproto_file_type);
138 }
139
140 afs_set_i_size(vnode, status->size);
141 afs_set_netfs_context(vnode);
142
143 vnode->invalid_before = status->data_version;
144 inode_set_iversion_raw(&vnode->netfs.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->netfs.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 & S_IALLUGO;
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 (op=%x)\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 op->debug_id);
224
225 vnode->invalid_before = status->data_version;
226 if (vnode->status.type == AFS_FTYPE_DIR) {
227 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
228 afs_stat_v(vnode, n_inval);
229 } else {
230 set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
231 }
232 change_size = true;
233 } else if (vnode->status.type == AFS_FTYPE_DIR) {
234 /* Expected directory change is handled elsewhere so
235 * that we can locally edit the directory and save on a
236 * download.
237 */
238 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
239 data_changed = false;
240 change_size = true;
241 }
242
243 if (data_changed) {
244 inode_set_iversion_raw(inode, status->data_version);
245
246 /* Only update the size if the data version jumped. If the
247 * file is being modified locally, then we might have our own
248 * idea of what the size should be that's not the same as
249 * what's on the server.
250 */
251 vnode->netfs.remote_i_size = status->size;
252 if (change_size) {
253 afs_set_i_size(vnode, status->size);
254 inode->i_ctime = t;
255 inode->i_atime = t;
256 }
257 }
258 }
259
260 /*
261 * Apply a callback to a vnode.
262 */
afs_apply_callback(struct afs_operation * op,struct afs_vnode_param * vp)263 static void afs_apply_callback(struct afs_operation *op,
264 struct afs_vnode_param *vp)
265 {
266 struct afs_callback *cb = &vp->scb.callback;
267 struct afs_vnode *vnode = vp->vnode;
268
269 if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
270 vnode->cb_expires_at = cb->expires_at;
271 vnode->cb_server = op->server;
272 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
273 }
274 }
275
276 /*
277 * Apply the received status and callback to an inode all in the same critical
278 * section to avoid races with afs_validate().
279 */
afs_vnode_commit_status(struct afs_operation * op,struct afs_vnode_param * vp)280 void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
281 {
282 struct afs_vnode *vnode = vp->vnode;
283
284 _enter("");
285
286 write_seqlock(&vnode->cb_lock);
287
288 if (vp->scb.have_error) {
289 /* A YFS server will return this from RemoveFile2 and AFS and
290 * YFS will return this from InlineBulkStatus.
291 */
292 if (vp->scb.status.abort_code == VNOVNODE) {
293 set_bit(AFS_VNODE_DELETED, &vnode->flags);
294 clear_nlink(&vnode->netfs.inode);
295 __afs_break_callback(vnode, afs_cb_break_for_deleted);
296 op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
297 }
298 } else if (vp->scb.have_status) {
299 if (vp->speculative &&
300 (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
301 vp->dv_before != vnode->status.data_version))
302 /* Ignore the result of a speculative bulk status fetch
303 * if it splits around a modification op, thereby
304 * appearing to regress the data version.
305 */
306 goto out;
307 afs_apply_status(op, vp);
308 if (vp->scb.have_cb)
309 afs_apply_callback(op, vp);
310 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
311 drop_nlink(&vnode->netfs.inode);
312 if (vnode->netfs.inode.i_nlink == 0) {
313 set_bit(AFS_VNODE_DELETED, &vnode->flags);
314 __afs_break_callback(vnode, afs_cb_break_for_deleted);
315 }
316 }
317
318 out:
319 write_sequnlock(&vnode->cb_lock);
320
321 if (vp->scb.have_status)
322 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
323 }
324
afs_fetch_status_success(struct afs_operation * op)325 static void afs_fetch_status_success(struct afs_operation *op)
326 {
327 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
328 struct afs_vnode *vnode = vp->vnode;
329 int ret;
330
331 if (vnode->netfs.inode.i_state & I_NEW) {
332 ret = afs_inode_init_from_status(op, vp, vnode);
333 op->error = ret;
334 if (ret == 0)
335 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
336 } else {
337 afs_vnode_commit_status(op, vp);
338 }
339 }
340
341 const struct afs_operation_ops afs_fetch_status_operation = {
342 .issue_afs_rpc = afs_fs_fetch_status,
343 .issue_yfs_rpc = yfs_fs_fetch_status,
344 .success = afs_fetch_status_success,
345 .aborted = afs_check_for_remote_deletion,
346 };
347
348 /*
349 * Fetch file status from the volume.
350 */
afs_fetch_status(struct afs_vnode * vnode,struct key * key,bool is_new,afs_access_t * _caller_access)351 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
352 afs_access_t *_caller_access)
353 {
354 struct afs_operation *op;
355
356 _enter("%s,{%llx:%llu.%u,S=%lx}",
357 vnode->volume->name,
358 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
359 vnode->flags);
360
361 op = afs_alloc_operation(key, vnode->volume);
362 if (IS_ERR(op))
363 return PTR_ERR(op);
364
365 afs_op_set_vnode(op, 0, vnode);
366
367 op->nr_files = 1;
368 op->ops = &afs_fetch_status_operation;
369 afs_begin_vnode_operation(op);
370 afs_wait_for_operation(op);
371
372 if (_caller_access)
373 *_caller_access = op->file[0].scb.status.caller_access;
374 return afs_put_operation(op);
375 }
376
377 /*
378 * ilookup() comparator
379 */
afs_ilookup5_test_by_fid(struct inode * inode,void * opaque)380 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
381 {
382 struct afs_vnode *vnode = AFS_FS_I(inode);
383 struct afs_fid *fid = opaque;
384
385 return (fid->vnode == vnode->fid.vnode &&
386 fid->vnode_hi == vnode->fid.vnode_hi &&
387 fid->unique == vnode->fid.unique);
388 }
389
390 /*
391 * iget5() comparator
392 */
afs_iget5_test(struct inode * inode,void * opaque)393 static int afs_iget5_test(struct inode *inode, void *opaque)
394 {
395 struct afs_vnode_param *vp = opaque;
396 //struct afs_vnode *vnode = AFS_FS_I(inode);
397
398 return afs_ilookup5_test_by_fid(inode, &vp->fid);
399 }
400
401 /*
402 * iget5() inode initialiser
403 */
afs_iget5_set(struct inode * inode,void * opaque)404 static int afs_iget5_set(struct inode *inode, void *opaque)
405 {
406 struct afs_vnode_param *vp = opaque;
407 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
408 struct afs_vnode *vnode = AFS_FS_I(inode);
409
410 vnode->volume = as->volume;
411 vnode->fid = vp->fid;
412
413 /* YFS supports 96-bit vnode IDs, but Linux only supports
414 * 64-bit inode numbers.
415 */
416 inode->i_ino = vnode->fid.vnode;
417 inode->i_generation = vnode->fid.unique;
418 return 0;
419 }
420
421 /*
422 * Get a cache cookie for an inode.
423 */
afs_get_inode_cache(struct afs_vnode * vnode)424 static void afs_get_inode_cache(struct afs_vnode *vnode)
425 {
426 #ifdef CONFIG_AFS_FSCACHE
427 struct {
428 __be32 vnode_id;
429 __be32 unique;
430 __be32 vnode_id_ext[2]; /* Allow for a 96-bit key */
431 } __packed key;
432 struct afs_vnode_cache_aux aux;
433
434 if (vnode->status.type != AFS_FTYPE_FILE) {
435 vnode->netfs.cache = NULL;
436 return;
437 }
438
439 key.vnode_id = htonl(vnode->fid.vnode);
440 key.unique = htonl(vnode->fid.unique);
441 key.vnode_id_ext[0] = htonl(vnode->fid.vnode >> 32);
442 key.vnode_id_ext[1] = htonl(vnode->fid.vnode_hi);
443 afs_set_cache_aux(vnode, &aux);
444
445 afs_vnode_set_cache(vnode,
446 fscache_acquire_cookie(
447 vnode->volume->cache,
448 vnode->status.type == AFS_FTYPE_FILE ?
449 0 : FSCACHE_ADV_SINGLE_CHUNK,
450 &key, sizeof(key),
451 &aux, sizeof(aux),
452 vnode->status.size));
453 #endif
454 }
455
456 /*
457 * inode retrieval
458 */
afs_iget(struct afs_operation * op,struct afs_vnode_param * vp)459 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
460 {
461 struct afs_vnode_param *dvp = &op->file[0];
462 struct super_block *sb = dvp->vnode->netfs.inode.i_sb;
463 struct afs_vnode *vnode;
464 struct inode *inode;
465 int ret;
466
467 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
468
469 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
470 if (!inode) {
471 _leave(" = -ENOMEM");
472 return ERR_PTR(-ENOMEM);
473 }
474
475 vnode = AFS_FS_I(inode);
476
477 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
478 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
479
480 /* deal with an existing inode */
481 if (!(inode->i_state & I_NEW)) {
482 _leave(" = %p", inode);
483 return inode;
484 }
485
486 ret = afs_inode_init_from_status(op, vp, vnode);
487 if (ret < 0)
488 goto bad_inode;
489
490 afs_get_inode_cache(vnode);
491
492 /* success */
493 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
494 unlock_new_inode(inode);
495 _leave(" = %p", inode);
496 return inode;
497
498 /* failure */
499 bad_inode:
500 iget_failed(inode);
501 _leave(" = %d [bad]", ret);
502 return ERR_PTR(ret);
503 }
504
afs_iget5_set_root(struct inode * inode,void * opaque)505 static int afs_iget5_set_root(struct inode *inode, void *opaque)
506 {
507 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
508 struct afs_vnode *vnode = AFS_FS_I(inode);
509
510 vnode->volume = as->volume;
511 vnode->fid.vid = as->volume->vid,
512 vnode->fid.vnode = 1;
513 vnode->fid.unique = 1;
514 inode->i_ino = 1;
515 inode->i_generation = 1;
516 return 0;
517 }
518
519 /*
520 * Set up the root inode for a volume. This is always vnode 1, unique 1 within
521 * the volume.
522 */
afs_root_iget(struct super_block * sb,struct key * key)523 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
524 {
525 struct afs_super_info *as = AFS_FS_S(sb);
526 struct afs_operation *op;
527 struct afs_vnode *vnode;
528 struct inode *inode;
529 int ret;
530
531 _enter(",{%llx},,", as->volume->vid);
532
533 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
534 if (!inode) {
535 _leave(" = -ENOMEM");
536 return ERR_PTR(-ENOMEM);
537 }
538
539 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
540
541 BUG_ON(!(inode->i_state & I_NEW));
542
543 vnode = AFS_FS_I(inode);
544 vnode->cb_v_break = as->volume->cb_v_break,
545 afs_set_netfs_context(vnode);
546
547 op = afs_alloc_operation(key, as->volume);
548 if (IS_ERR(op)) {
549 ret = PTR_ERR(op);
550 goto error;
551 }
552
553 afs_op_set_vnode(op, 0, vnode);
554
555 op->nr_files = 1;
556 op->ops = &afs_fetch_status_operation;
557 ret = afs_do_sync_operation(op);
558 if (ret < 0)
559 goto error;
560
561 afs_get_inode_cache(vnode);
562
563 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
564 unlock_new_inode(inode);
565 _leave(" = %p", inode);
566 return inode;
567
568 error:
569 iget_failed(inode);
570 _leave(" = %d [bad]", ret);
571 return ERR_PTR(ret);
572 }
573
574 /*
575 * mark the data attached to an inode as obsolete due to a write on the server
576 * - might also want to ditch all the outstanding writes and dirty pages
577 */
afs_zap_data(struct afs_vnode * vnode)578 static void afs_zap_data(struct afs_vnode *vnode)
579 {
580 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
581
582 afs_invalidate_cache(vnode, 0);
583
584 /* nuke all the non-dirty pages that aren't locked, mapped or being
585 * written back in a regular file and completely discard the pages in a
586 * directory or symlink */
587 if (S_ISREG(vnode->netfs.inode.i_mode))
588 invalidate_remote_inode(&vnode->netfs.inode);
589 else
590 invalidate_inode_pages2(vnode->netfs.inode.i_mapping);
591 }
592
593 /*
594 * Check to see if we have a server currently serving this volume and that it
595 * hasn't been reinitialised or dropped from the list.
596 */
afs_check_server_good(struct afs_vnode * vnode)597 static bool afs_check_server_good(struct afs_vnode *vnode)
598 {
599 struct afs_server_list *slist;
600 struct afs_server *server;
601 bool good;
602 int i;
603
604 if (vnode->cb_fs_s_break == atomic_read(&vnode->volume->cell->fs_s_break))
605 return true;
606
607 rcu_read_lock();
608
609 slist = rcu_dereference(vnode->volume->servers);
610 for (i = 0; i < slist->nr_servers; i++) {
611 server = slist->servers[i].server;
612 if (server == vnode->cb_server) {
613 good = (vnode->cb_s_break == server->cb_s_break);
614 rcu_read_unlock();
615 return good;
616 }
617 }
618
619 rcu_read_unlock();
620 return false;
621 }
622
623 /*
624 * Check the validity of a vnode/inode.
625 */
afs_check_validity(struct afs_vnode * vnode)626 bool afs_check_validity(struct afs_vnode *vnode)
627 {
628 enum afs_cb_break_reason need_clear = afs_cb_break_no_break;
629 time64_t now = ktime_get_real_seconds();
630 unsigned int cb_break;
631 int seq = 0;
632
633 do {
634 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
635 cb_break = vnode->cb_break;
636
637 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
638 if (vnode->cb_v_break != vnode->volume->cb_v_break)
639 need_clear = afs_cb_break_for_v_break;
640 else if (!afs_check_server_good(vnode))
641 need_clear = afs_cb_break_for_s_reinit;
642 else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
643 need_clear = afs_cb_break_for_zap;
644 else if (vnode->cb_expires_at - 10 <= now)
645 need_clear = afs_cb_break_for_lapsed;
646 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
647 ;
648 } else {
649 need_clear = afs_cb_break_no_promise;
650 }
651
652 } while (need_seqretry(&vnode->cb_lock, seq));
653
654 done_seqretry(&vnode->cb_lock, seq);
655
656 if (need_clear == afs_cb_break_no_break)
657 return true;
658
659 write_seqlock(&vnode->cb_lock);
660 if (need_clear == afs_cb_break_no_promise)
661 vnode->cb_v_break = vnode->volume->cb_v_break;
662 else if (cb_break == vnode->cb_break)
663 __afs_break_callback(vnode, need_clear);
664 else
665 trace_afs_cb_miss(&vnode->fid, need_clear);
666 write_sequnlock(&vnode->cb_lock);
667 return false;
668 }
669
670 /*
671 * validate a vnode/inode
672 * - there are several things we need to check
673 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
674 * symlink)
675 * - parent dir metadata changed (security changes)
676 * - dentry data changed (write, truncate)
677 * - dentry metadata changed (security changes)
678 */
afs_validate(struct afs_vnode * vnode,struct key * key)679 int afs_validate(struct afs_vnode *vnode, struct key *key)
680 {
681 int ret;
682
683 _enter("{v={%llx:%llu} fl=%lx},%x",
684 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
685 key_serial(key));
686
687 if (unlikely(test_bit(AFS_VNODE_DELETED, &vnode->flags))) {
688 if (vnode->netfs.inode.i_nlink)
689 clear_nlink(&vnode->netfs.inode);
690 goto valid;
691 }
692
693 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&
694 afs_check_validity(vnode))
695 goto valid;
696
697 down_write(&vnode->validate_lock);
698
699 /* if the promise has expired, we need to check the server again to get
700 * a new promise - note that if the (parent) directory's metadata was
701 * changed then the security may be different and we may no longer have
702 * access */
703 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
704 _debug("not promised");
705 ret = afs_fetch_status(vnode, key, false, NULL);
706 if (ret < 0) {
707 if (ret == -ENOENT) {
708 set_bit(AFS_VNODE_DELETED, &vnode->flags);
709 ret = -ESTALE;
710 }
711 goto error_unlock;
712 }
713 _debug("new promise [fl=%lx]", vnode->flags);
714 }
715
716 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
717 _debug("file already deleted");
718 ret = -ESTALE;
719 goto error_unlock;
720 }
721
722 /* if the vnode's data version number changed then its contents are
723 * different */
724 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
725 afs_zap_data(vnode);
726 up_write(&vnode->validate_lock);
727 valid:
728 _leave(" = 0");
729 return 0;
730
731 error_unlock:
732 up_write(&vnode->validate_lock);
733 _leave(" = %d", ret);
734 return ret;
735 }
736
737 /*
738 * read the attributes of an inode
739 */
afs_getattr(struct user_namespace * mnt_userns,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)740 int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,
741 struct kstat *stat, u32 request_mask, unsigned int query_flags)
742 {
743 struct inode *inode = d_inode(path->dentry);
744 struct afs_vnode *vnode = AFS_FS_I(inode);
745 struct key *key;
746 int ret, seq = 0;
747
748 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
749
750 if (vnode->volume &&
751 !(query_flags & AT_STATX_DONT_SYNC) &&
752 !test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
753 key = afs_request_key(vnode->volume->cell);
754 if (IS_ERR(key))
755 return PTR_ERR(key);
756 ret = afs_validate(vnode, key);
757 key_put(key);
758 if (ret < 0)
759 return ret;
760 }
761
762 do {
763 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
764 generic_fillattr(&init_user_ns, inode, stat);
765 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
766 stat->nlink > 0)
767 stat->nlink -= 1;
768 } while (need_seqretry(&vnode->cb_lock, seq));
769
770 done_seqretry(&vnode->cb_lock, seq);
771 return 0;
772 }
773
774 /*
775 * discard an AFS inode
776 */
afs_drop_inode(struct inode * inode)777 int afs_drop_inode(struct inode *inode)
778 {
779 _enter("");
780
781 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
782 return generic_delete_inode(inode);
783 else
784 return generic_drop_inode(inode);
785 }
786
787 /*
788 * clear an AFS inode
789 */
afs_evict_inode(struct inode * inode)790 void afs_evict_inode(struct inode *inode)
791 {
792 struct afs_vnode_cache_aux aux;
793 struct afs_vnode *vnode = AFS_FS_I(inode);
794
795 _enter("{%llx:%llu.%d}",
796 vnode->fid.vid,
797 vnode->fid.vnode,
798 vnode->fid.unique);
799
800 _debug("CLEAR INODE %p", inode);
801
802 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
803
804 truncate_inode_pages_final(&inode->i_data);
805
806 afs_set_cache_aux(vnode, &aux);
807 fscache_clear_inode_writeback(afs_vnode_cache(vnode), inode, &aux);
808 clear_inode(inode);
809
810 while (!list_empty(&vnode->wb_keys)) {
811 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
812 struct afs_wb_key, vnode_link);
813 list_del(&wbk->vnode_link);
814 afs_put_wb_key(wbk);
815 }
816
817 fscache_relinquish_cookie(afs_vnode_cache(vnode),
818 test_bit(AFS_VNODE_DELETED, &vnode->flags));
819
820 afs_prune_wb_keys(vnode);
821 afs_put_permits(rcu_access_pointer(vnode->permit_cache));
822 key_put(vnode->silly_key);
823 vnode->silly_key = NULL;
824 key_put(vnode->lock_key);
825 vnode->lock_key = NULL;
826 _leave("");
827 }
828
afs_setattr_success(struct afs_operation * op)829 static void afs_setattr_success(struct afs_operation *op)
830 {
831 struct afs_vnode_param *vp = &op->file[0];
832 struct inode *inode = &vp->vnode->netfs.inode;
833 loff_t old_i_size = i_size_read(inode);
834
835 op->setattr.old_i_size = old_i_size;
836 afs_vnode_commit_status(op, vp);
837 /* inode->i_size has now been changed. */
838
839 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
840 loff_t size = op->setattr.attr->ia_size;
841 if (size > old_i_size)
842 pagecache_isize_extended(inode, old_i_size, size);
843 }
844 }
845
afs_setattr_edit_file(struct afs_operation * op)846 static void afs_setattr_edit_file(struct afs_operation *op)
847 {
848 struct afs_vnode_param *vp = &op->file[0];
849 struct inode *inode = &vp->vnode->netfs.inode;
850
851 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
852 loff_t size = op->setattr.attr->ia_size;
853 loff_t i_size = op->setattr.old_i_size;
854
855 if (size < i_size)
856 truncate_pagecache(inode, size);
857 if (size != i_size)
858 fscache_resize_cookie(afs_vnode_cache(vp->vnode),
859 vp->scb.status.size);
860 }
861 }
862
863 static const struct afs_operation_ops afs_setattr_operation = {
864 .issue_afs_rpc = afs_fs_setattr,
865 .issue_yfs_rpc = yfs_fs_setattr,
866 .success = afs_setattr_success,
867 .edit_dir = afs_setattr_edit_file,
868 };
869
870 /*
871 * set the attributes of an inode
872 */
afs_setattr(struct user_namespace * mnt_userns,struct dentry * dentry,struct iattr * attr)873 int afs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
874 struct iattr *attr)
875 {
876 const unsigned int supported =
877 ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
878 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET | ATTR_TOUCH;
879 struct afs_operation *op;
880 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
881 struct inode *inode = &vnode->netfs.inode;
882 loff_t i_size;
883 int ret;
884
885 _enter("{%llx:%llu},{n=%pd},%x",
886 vnode->fid.vid, vnode->fid.vnode, dentry,
887 attr->ia_valid);
888
889 if (!(attr->ia_valid & supported)) {
890 _leave(" = 0 [unsupported]");
891 return 0;
892 }
893
894 i_size = i_size_read(inode);
895 if (attr->ia_valid & ATTR_SIZE) {
896 if (!S_ISREG(inode->i_mode))
897 return -EISDIR;
898
899 ret = inode_newsize_ok(inode, attr->ia_size);
900 if (ret)
901 return ret;
902
903 if (attr->ia_size == i_size)
904 attr->ia_valid &= ~ATTR_SIZE;
905 }
906
907 fscache_use_cookie(afs_vnode_cache(vnode), true);
908
909 /* Prevent any new writebacks from starting whilst we do this. */
910 down_write(&vnode->validate_lock);
911
912 if ((attr->ia_valid & ATTR_SIZE) && S_ISREG(inode->i_mode)) {
913 loff_t size = attr->ia_size;
914
915 /* Wait for any outstanding writes to the server to complete */
916 loff_t from = min(size, i_size);
917 loff_t to = max(size, i_size);
918 ret = filemap_fdatawait_range(inode->i_mapping, from, to);
919 if (ret < 0)
920 goto out_unlock;
921
922 /* Don't talk to the server if we're just shortening in-memory
923 * writes that haven't gone to the server yet.
924 */
925 if (!(attr->ia_valid & (supported & ~ATTR_SIZE & ~ATTR_MTIME)) &&
926 attr->ia_size < i_size &&
927 attr->ia_size > vnode->status.size) {
928 truncate_pagecache(inode, attr->ia_size);
929 fscache_resize_cookie(afs_vnode_cache(vnode),
930 attr->ia_size);
931 i_size_write(inode, attr->ia_size);
932 ret = 0;
933 goto out_unlock;
934 }
935 }
936
937 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
938 afs_file_key(attr->ia_file) : NULL),
939 vnode->volume);
940 if (IS_ERR(op)) {
941 ret = PTR_ERR(op);
942 goto out_unlock;
943 }
944
945 afs_op_set_vnode(op, 0, vnode);
946 op->setattr.attr = attr;
947
948 if (attr->ia_valid & ATTR_SIZE) {
949 op->file[0].dv_delta = 1;
950 op->file[0].set_size = true;
951 }
952 op->ctime = attr->ia_ctime;
953 op->file[0].update_ctime = 1;
954 op->file[0].modification = true;
955
956 op->ops = &afs_setattr_operation;
957 ret = afs_do_sync_operation(op);
958
959 out_unlock:
960 up_write(&vnode->validate_lock);
961 fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);
962 _leave(" = %d", ret);
963 return ret;
964 }
965
