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 the file size and block count. Estimate the number of 512 bytes blocks
58 * used, rounded up to nearest 1K for consistency with other AFS clients.
59 */
afs_set_i_size(struct afs_vnode * vnode,u64 size)60 static void afs_set_i_size(struct afs_vnode *vnode, u64 size)
61 {
62 i_size_write(&vnode->vfs_inode, size);
63 vnode->vfs_inode.i_blocks = ((size + 1023) >> 10) << 1;
64 }
65
66 /*
67 * Initialise an inode from the vnode status.
68 */
afs_inode_init_from_status(struct afs_operation * op,struct afs_vnode_param * vp,struct afs_vnode * vnode)69 static int afs_inode_init_from_status(struct afs_operation *op,
70 struct afs_vnode_param *vp,
71 struct afs_vnode *vnode)
72 {
73 struct afs_file_status *status = &vp->scb.status;
74 struct inode *inode = AFS_VNODE_TO_I(vnode);
75 struct timespec64 t;
76
77 _enter("{%llx:%llu.%u} %s",
78 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
79 op->type ? op->type->name : "???");
80
81 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
82 status->type,
83 status->nlink,
84 (unsigned long long) status->size,
85 status->data_version,
86 status->mode);
87
88 write_seqlock(&vnode->cb_lock);
89
90 vnode->cb_v_break = op->cb_v_break;
91 vnode->cb_s_break = op->cb_s_break;
92 vnode->status = *status;
93
94 t = status->mtime_client;
95 inode->i_ctime = t;
96 inode->i_mtime = t;
97 inode->i_atime = t;
98 inode->i_flags |= S_NOATIME;
99 inode->i_uid = make_kuid(&init_user_ns, status->owner);
100 inode->i_gid = make_kgid(&init_user_ns, status->group);
101 set_nlink(&vnode->vfs_inode, status->nlink);
102
103 switch (status->type) {
104 case AFS_FTYPE_FILE:
105 inode->i_mode = S_IFREG | (status->mode & S_IALLUGO);
106 inode->i_op = &afs_file_inode_operations;
107 inode->i_fop = &afs_file_operations;
108 inode->i_mapping->a_ops = &afs_fs_aops;
109 break;
110 case AFS_FTYPE_DIR:
111 inode->i_mode = S_IFDIR | (status->mode & S_IALLUGO);
112 inode->i_op = &afs_dir_inode_operations;
113 inode->i_fop = &afs_dir_file_operations;
114 inode->i_mapping->a_ops = &afs_dir_aops;
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_fs_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_fs_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
142 vnode->invalid_before = status->data_version;
143 inode_set_iversion_raw(&vnode->vfs_inode, status->data_version);
144
145 if (!vp->scb.have_cb) {
146 /* it's a symlink we just created (the fileserver
147 * didn't give us a callback) */
148 vnode->cb_expires_at = ktime_get_real_seconds();
149 } else {
150 vnode->cb_expires_at = vp->scb.callback.expires_at;
151 vnode->cb_server = op->server;
152 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
153 }
154
155 write_sequnlock(&vnode->cb_lock);
156 return 0;
157 }
158
159 /*
160 * Update the core inode struct from a returned status record.
161 */
afs_apply_status(struct afs_operation * op,struct afs_vnode_param * vp)162 static void afs_apply_status(struct afs_operation *op,
163 struct afs_vnode_param *vp)
164 {
165 struct afs_file_status *status = &vp->scb.status;
166 struct afs_vnode *vnode = vp->vnode;
167 struct inode *inode = &vnode->vfs_inode;
168 struct timespec64 t;
169 umode_t mode;
170 bool data_changed = false;
171 bool change_size = vp->set_size;
172
173 _enter("{%llx:%llu.%u} %s",
174 vp->fid.vid, vp->fid.vnode, vp->fid.unique,
175 op->type ? op->type->name : "???");
176
177 BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
178
179 if (status->type != vnode->status.type) {
180 pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",
181 vnode->fid.vid,
182 vnode->fid.vnode,
183 vnode->fid.unique,
184 status->type, vnode->status.type);
185 afs_protocol_error(NULL, afs_eproto_bad_status);
186 return;
187 }
188
189 if (status->nlink != vnode->status.nlink)
190 set_nlink(inode, status->nlink);
191
192 if (status->owner != vnode->status.owner)
193 inode->i_uid = make_kuid(&init_user_ns, status->owner);
194
195 if (status->group != vnode->status.group)
196 inode->i_gid = make_kgid(&init_user_ns, status->group);
197
198 if (status->mode != vnode->status.mode) {
199 mode = inode->i_mode;
200 mode &= ~S_IALLUGO;
201 mode |= status->mode & S_IALLUGO;
202 WRITE_ONCE(inode->i_mode, mode);
203 }
204
205 t = status->mtime_client;
206 inode->i_mtime = t;
207 if (vp->update_ctime)
208 inode->i_ctime = op->ctime;
209
210 if (vnode->status.data_version != status->data_version)
211 data_changed = true;
212
213 vnode->status = *status;
214
215 if (vp->dv_before + vp->dv_delta != status->data_version) {
216 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags))
217 pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s (op=%x)\n",
218 vnode->fid.vid, vnode->fid.vnode,
219 (unsigned long long)vp->dv_before + vp->dv_delta,
220 (unsigned long long)status->data_version,
221 op->type ? op->type->name : "???",
222 op->debug_id);
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->speculative &&
298 (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
299 vp->dv_before != vnode->status.data_version))
300 /* Ignore the result of a speculative bulk status fetch
301 * if it splits around a modification op, thereby
302 * appearing to regress the data version.
303 */
304 goto out;
305 afs_apply_status(op, vp);
306 if (vp->scb.have_cb)
307 afs_apply_callback(op, vp);
308 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
309 drop_nlink(&vnode->vfs_inode);
310 if (vnode->vfs_inode.i_nlink == 0) {
311 set_bit(AFS_VNODE_DELETED, &vnode->flags);
312 __afs_break_callback(vnode, afs_cb_break_for_deleted);
313 }
314 }
315
316 out:
317 write_sequnlock(&vnode->cb_lock);
318
319 if (vp->scb.have_status)
320 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
321 }
322
afs_fetch_status_success(struct afs_operation * op)323 static void afs_fetch_status_success(struct afs_operation *op)
324 {
325 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
326 struct afs_vnode *vnode = vp->vnode;
327 int ret;
328
329 if (vnode->vfs_inode.i_state & I_NEW) {
330 ret = afs_inode_init_from_status(op, vp, vnode);
331 op->error = ret;
332 if (ret == 0)
333 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
334 } else {
335 afs_vnode_commit_status(op, vp);
336 }
337 }
338
339 const struct afs_operation_ops afs_fetch_status_operation = {
340 .issue_afs_rpc = afs_fs_fetch_status,
341 .issue_yfs_rpc = yfs_fs_fetch_status,
342 .success = afs_fetch_status_success,
343 .aborted = afs_check_for_remote_deletion,
344 };
345
346 /*
347 * Fetch file status from the volume.
348 */
afs_fetch_status(struct afs_vnode * vnode,struct key * key,bool is_new,afs_access_t * _caller_access)349 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
350 afs_access_t *_caller_access)
351 {
352 struct afs_operation *op;
353
354 _enter("%s,{%llx:%llu.%u,S=%lx}",
355 vnode->volume->name,
356 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
357 vnode->flags);
358
359 op = afs_alloc_operation(key, vnode->volume);
360 if (IS_ERR(op))
361 return PTR_ERR(op);
362
363 afs_op_set_vnode(op, 0, vnode);
364
365 op->nr_files = 1;
366 op->ops = &afs_fetch_status_operation;
367 afs_begin_vnode_operation(op);
368 afs_wait_for_operation(op);
369
370 if (_caller_access)
371 *_caller_access = op->file[0].scb.status.caller_access;
372 return afs_put_operation(op);
373 }
374
375 /*
376 * ilookup() comparator
377 */
afs_ilookup5_test_by_fid(struct inode * inode,void * opaque)378 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
379 {
380 struct afs_vnode *vnode = AFS_FS_I(inode);
381 struct afs_fid *fid = opaque;
382
383 return (fid->vnode == vnode->fid.vnode &&
384 fid->vnode_hi == vnode->fid.vnode_hi &&
385 fid->unique == vnode->fid.unique);
386 }
387
388 /*
389 * iget5() comparator
390 */
afs_iget5_test(struct inode * inode,void * opaque)391 static int afs_iget5_test(struct inode *inode, void *opaque)
392 {
393 struct afs_vnode_param *vp = opaque;
394 //struct afs_vnode *vnode = AFS_FS_I(inode);
395
396 return afs_ilookup5_test_by_fid(inode, &vp->fid);
397 }
398
399 /*
400 * iget5() inode initialiser
401 */
afs_iget5_set(struct inode * inode,void * opaque)402 static int afs_iget5_set(struct inode *inode, void *opaque)
403 {
404 struct afs_vnode_param *vp = opaque;
405 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
406 struct afs_vnode *vnode = AFS_FS_I(inode);
407
408 vnode->volume = as->volume;
409 vnode->fid = vp->fid;
410
411 /* YFS supports 96-bit vnode IDs, but Linux only supports
412 * 64-bit inode numbers.
413 */
414 inode->i_ino = vnode->fid.vnode;
415 inode->i_generation = vnode->fid.unique;
416 return 0;
417 }
418
419 /*
420 * Get a cache cookie for an inode.
421 */
afs_get_inode_cache(struct afs_vnode * vnode)422 static void afs_get_inode_cache(struct afs_vnode *vnode)
423 {
424 #ifdef CONFIG_AFS_FSCACHE
425 struct {
426 u32 vnode_id;
427 u32 unique;
428 u32 vnode_id_ext[2]; /* Allow for a 96-bit key */
429 } __packed key;
430 struct afs_vnode_cache_aux aux;
431
432 if (vnode->status.type != AFS_FTYPE_FILE) {
433 vnode->cache = NULL;
434 return;
435 }
436
437 key.vnode_id = vnode->fid.vnode;
438 key.unique = vnode->fid.unique;
439 key.vnode_id_ext[0] = vnode->fid.vnode >> 32;
440 key.vnode_id_ext[1] = vnode->fid.vnode_hi;
441 aux.data_version = vnode->status.data_version;
442
443 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
444 &afs_vnode_cache_index_def,
445 &key, sizeof(key),
446 &aux, sizeof(aux),
447 vnode, vnode->status.size, true);
448 #endif
449 }
450
451 /*
452 * inode retrieval
453 */
afs_iget(struct afs_operation * op,struct afs_vnode_param * vp)454 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
455 {
456 struct afs_vnode_param *dvp = &op->file[0];
457 struct super_block *sb = dvp->vnode->vfs_inode.i_sb;
458 struct afs_vnode *vnode;
459 struct inode *inode;
460 int ret;
461
462 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
463
464 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
465 if (!inode) {
466 _leave(" = -ENOMEM");
467 return ERR_PTR(-ENOMEM);
468 }
469
470 vnode = AFS_FS_I(inode);
471
472 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
473 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
474
475 /* deal with an existing inode */
476 if (!(inode->i_state & I_NEW)) {
477 _leave(" = %p", inode);
478 return inode;
479 }
480
481 ret = afs_inode_init_from_status(op, vp, vnode);
482 if (ret < 0)
483 goto bad_inode;
484
485 afs_get_inode_cache(vnode);
486
487 /* success */
488 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
489 unlock_new_inode(inode);
490 _leave(" = %p", inode);
491 return inode;
492
493 /* failure */
494 bad_inode:
495 iget_failed(inode);
496 _leave(" = %d [bad]", ret);
497 return ERR_PTR(ret);
498 }
499
afs_iget5_set_root(struct inode * inode,void * opaque)500 static int afs_iget5_set_root(struct inode *inode, void *opaque)
501 {
502 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
503 struct afs_vnode *vnode = AFS_FS_I(inode);
504
505 vnode->volume = as->volume;
506 vnode->fid.vid = as->volume->vid,
507 vnode->fid.vnode = 1;
508 vnode->fid.unique = 1;
509 inode->i_ino = 1;
510 inode->i_generation = 1;
511 return 0;
512 }
513
514 /*
515 * Set up the root inode for a volume. This is always vnode 1, unique 1 within
516 * the volume.
517 */
afs_root_iget(struct super_block * sb,struct key * key)518 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
519 {
520 struct afs_super_info *as = AFS_FS_S(sb);
521 struct afs_operation *op;
522 struct afs_vnode *vnode;
523 struct inode *inode;
524 int ret;
525
526 _enter(",{%llx},,", as->volume->vid);
527
528 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
529 if (!inode) {
530 _leave(" = -ENOMEM");
531 return ERR_PTR(-ENOMEM);
532 }
533
534 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
535
536 BUG_ON(!(inode->i_state & I_NEW));
537
538 vnode = AFS_FS_I(inode);
539 vnode->cb_v_break = as->volume->cb_v_break,
540
541 op = afs_alloc_operation(key, as->volume);
542 if (IS_ERR(op)) {
543 ret = PTR_ERR(op);
544 goto error;
545 }
546
547 afs_op_set_vnode(op, 0, vnode);
548
549 op->nr_files = 1;
550 op->ops = &afs_fetch_status_operation;
551 ret = afs_do_sync_operation(op);
552 if (ret < 0)
553 goto error;
554
555 afs_get_inode_cache(vnode);
556
557 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
558 unlock_new_inode(inode);
559 _leave(" = %p", inode);
560 return inode;
561
562 error:
563 iget_failed(inode);
564 _leave(" = %d [bad]", ret);
565 return ERR_PTR(ret);
566 }
567
568 /*
569 * mark the data attached to an inode as obsolete due to a write on the server
570 * - might also want to ditch all the outstanding writes and dirty pages
571 */
afs_zap_data(struct afs_vnode * vnode)572 static void afs_zap_data(struct afs_vnode *vnode)
573 {
574 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
575
576 #ifdef CONFIG_AFS_FSCACHE
577 fscache_invalidate(vnode->cache);
578 #endif
579
580 /* nuke all the non-dirty pages that aren't locked, mapped or being
581 * written back in a regular file and completely discard the pages in a
582 * directory or symlink */
583 if (S_ISREG(vnode->vfs_inode.i_mode))
584 invalidate_remote_inode(&vnode->vfs_inode);
585 else
586 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
587 }
588
589 /*
590 * Get the server reinit counter for a vnode's current server.
591 */
afs_get_s_break_rcu(struct afs_vnode * vnode,unsigned int * _s_break)592 static bool afs_get_s_break_rcu(struct afs_vnode *vnode, unsigned int *_s_break)
593 {
594 struct afs_server_list *slist = rcu_dereference(vnode->volume->servers);
595 struct afs_server *server;
596 int i;
597
598 for (i = 0; i < slist->nr_servers; i++) {
599 server = slist->servers[i].server;
600 if (server == vnode->cb_server) {
601 *_s_break = READ_ONCE(server->cb_s_break);
602 return true;
603 }
604 }
605
606 return false;
607 }
608
609 /*
610 * Check the validity of a vnode/inode.
611 */
afs_check_validity(struct afs_vnode * vnode)612 bool afs_check_validity(struct afs_vnode *vnode)
613 {
614 struct afs_volume *volume = vnode->volume;
615 enum afs_cb_break_reason need_clear = afs_cb_break_no_break;
616 time64_t now = ktime_get_real_seconds();
617 bool valid;
618 unsigned int cb_break, cb_s_break, cb_v_break;
619 int seq = 0;
620
621 do {
622 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
623 cb_v_break = READ_ONCE(volume->cb_v_break);
624 cb_break = vnode->cb_break;
625
626 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&
627 afs_get_s_break_rcu(vnode, &cb_s_break)) {
628 if (vnode->cb_s_break != cb_s_break ||
629 vnode->cb_v_break != cb_v_break) {
630 vnode->cb_s_break = cb_s_break;
631 vnode->cb_v_break = cb_v_break;
632 need_clear = afs_cb_break_for_vsbreak;
633 valid = false;
634 } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
635 need_clear = afs_cb_break_for_zap;
636 valid = false;
637 } else if (vnode->cb_expires_at - 10 <= now) {
638 need_clear = afs_cb_break_for_lapsed;
639 valid = false;
640 } else {
641 valid = true;
642 }
643 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
644 valid = true;
645 } else {
646 vnode->cb_v_break = cb_v_break;
647 valid = false;
648 }
649
650 } while (need_seqretry(&vnode->cb_lock, seq));
651
652 done_seqretry(&vnode->cb_lock, seq);
653
654 if (need_clear != afs_cb_break_no_break) {
655 write_seqlock(&vnode->cb_lock);
656 if (cb_break == vnode->cb_break)
657 __afs_break_callback(vnode, need_clear);
658 else
659 trace_afs_cb_miss(&vnode->fid, need_clear);
660 write_sequnlock(&vnode->cb_lock);
661 valid = false;
662 }
663
664 return valid;
665 }
666
667 /*
668 * validate a vnode/inode
669 * - there are several things we need to check
670 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
671 * symlink)
672 * - parent dir metadata changed (security changes)
673 * - dentry data changed (write, truncate)
674 * - dentry metadata changed (security changes)
675 */
afs_validate(struct afs_vnode * vnode,struct key * key)676 int afs_validate(struct afs_vnode *vnode, struct key *key)
677 {
678 bool valid;
679 int ret;
680
681 _enter("{v={%llx:%llu} fl=%lx},%x",
682 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
683 key_serial(key));
684
685 rcu_read_lock();
686 valid = afs_check_validity(vnode);
687 rcu_read_unlock();
688
689 if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
690 clear_nlink(&vnode->vfs_inode);
691
692 if (valid)
693 goto valid;
694
695 down_write(&vnode->validate_lock);
696
697 /* if the promise has expired, we need to check the server again to get
698 * a new promise - note that if the (parent) directory's metadata was
699 * changed then the security may be different and we may no longer have
700 * access */
701 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
702 _debug("not promised");
703 ret = afs_fetch_status(vnode, key, false, NULL);
704 if (ret < 0) {
705 if (ret == -ENOENT) {
706 set_bit(AFS_VNODE_DELETED, &vnode->flags);
707 ret = -ESTALE;
708 }
709 goto error_unlock;
710 }
711 _debug("new promise [fl=%lx]", vnode->flags);
712 }
713
714 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
715 _debug("file already deleted");
716 ret = -ESTALE;
717 goto error_unlock;
718 }
719
720 /* if the vnode's data version number changed then its contents are
721 * different */
722 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
723 afs_zap_data(vnode);
724 up_write(&vnode->validate_lock);
725 valid:
726 _leave(" = 0");
727 return 0;
728
729 error_unlock:
730 up_write(&vnode->validate_lock);
731 _leave(" = %d", ret);
732 return ret;
733 }
734
735 /*
736 * read the attributes of an inode
737 */
afs_getattr(struct user_namespace * mnt_userns,const struct path * path,struct kstat * stat,u32 request_mask,unsigned int query_flags)738 int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,
739 struct kstat *stat, u32 request_mask, unsigned int query_flags)
740 {
741 struct inode *inode = d_inode(path->dentry);
742 struct afs_vnode *vnode = AFS_FS_I(inode);
743 int seq = 0;
744
745 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
746
747 do {
748 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
749 generic_fillattr(&init_user_ns, inode, stat);
750 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
751 stat->nlink > 0)
752 stat->nlink -= 1;
753 } while (need_seqretry(&vnode->cb_lock, seq));
754
755 done_seqretry(&vnode->cb_lock, seq);
756 return 0;
757 }
758
759 /*
760 * discard an AFS inode
761 */
afs_drop_inode(struct inode * inode)762 int afs_drop_inode(struct inode *inode)
763 {
764 _enter("");
765
766 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
767 return generic_delete_inode(inode);
768 else
769 return generic_drop_inode(inode);
770 }
771
772 /*
773 * clear an AFS inode
774 */
afs_evict_inode(struct inode * inode)775 void afs_evict_inode(struct inode *inode)
776 {
777 struct afs_vnode *vnode;
778
779 vnode = AFS_FS_I(inode);
780
781 _enter("{%llx:%llu.%d}",
782 vnode->fid.vid,
783 vnode->fid.vnode,
784 vnode->fid.unique);
785
786 _debug("CLEAR INODE %p", inode);
787
788 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
789
790 truncate_inode_pages_final(&inode->i_data);
791 clear_inode(inode);
792
793 while (!list_empty(&vnode->wb_keys)) {
794 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
795 struct afs_wb_key, vnode_link);
796 list_del(&wbk->vnode_link);
797 afs_put_wb_key(wbk);
798 }
799
800 #ifdef CONFIG_AFS_FSCACHE
801 {
802 struct afs_vnode_cache_aux aux;
803
804 aux.data_version = vnode->status.data_version;
805 fscache_relinquish_cookie(vnode->cache, &aux,
806 test_bit(AFS_VNODE_DELETED, &vnode->flags));
807 vnode->cache = NULL;
808 }
809 #endif
810
811 afs_prune_wb_keys(vnode);
812 afs_put_permits(rcu_access_pointer(vnode->permit_cache));
813 key_put(vnode->silly_key);
814 vnode->silly_key = NULL;
815 key_put(vnode->lock_key);
816 vnode->lock_key = NULL;
817 _leave("");
818 }
819
afs_setattr_success(struct afs_operation * op)820 static void afs_setattr_success(struct afs_operation *op)
821 {
822 struct afs_vnode_param *vp = &op->file[0];
823 struct inode *inode = &vp->vnode->vfs_inode;
824 loff_t old_i_size = i_size_read(inode);
825
826 op->setattr.old_i_size = old_i_size;
827 afs_vnode_commit_status(op, vp);
828 /* inode->i_size has now been changed. */
829
830 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
831 loff_t size = op->setattr.attr->ia_size;
832 if (size > old_i_size)
833 pagecache_isize_extended(inode, old_i_size, size);
834 }
835 }
836
afs_setattr_edit_file(struct afs_operation * op)837 static void afs_setattr_edit_file(struct afs_operation *op)
838 {
839 struct afs_vnode_param *vp = &op->file[0];
840 struct inode *inode = &vp->vnode->vfs_inode;
841
842 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
843 loff_t size = op->setattr.attr->ia_size;
844 loff_t i_size = op->setattr.old_i_size;
845
846 if (size < i_size)
847 truncate_pagecache(inode, size);
848 }
849 }
850
851 static const struct afs_operation_ops afs_setattr_operation = {
852 .issue_afs_rpc = afs_fs_setattr,
853 .issue_yfs_rpc = yfs_fs_setattr,
854 .success = afs_setattr_success,
855 .edit_dir = afs_setattr_edit_file,
856 };
857
858 /*
859 * set the attributes of an inode
860 */
afs_setattr(struct user_namespace * mnt_userns,struct dentry * dentry,struct iattr * attr)861 int afs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
862 struct iattr *attr)
863 {
864 struct afs_operation *op;
865 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
866 int ret;
867
868 _enter("{%llx:%llu},{n=%pd},%x",
869 vnode->fid.vid, vnode->fid.vnode, dentry,
870 attr->ia_valid);
871
872 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
873 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET |
874 ATTR_TOUCH))) {
875 _leave(" = 0 [unsupported]");
876 return 0;
877 }
878
879 if (attr->ia_valid & ATTR_SIZE) {
880 if (!S_ISREG(vnode->vfs_inode.i_mode))
881 return -EISDIR;
882
883 ret = inode_newsize_ok(&vnode->vfs_inode, attr->ia_size);
884 if (ret)
885 return ret;
886
887 if (attr->ia_size == i_size_read(&vnode->vfs_inode))
888 attr->ia_valid &= ~ATTR_SIZE;
889 }
890
891 /* flush any dirty data outstanding on a regular file */
892 if (S_ISREG(vnode->vfs_inode.i_mode))
893 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
894
895 /* Prevent any new writebacks from starting whilst we do this. */
896 down_write(&vnode->validate_lock);
897
898 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
899 afs_file_key(attr->ia_file) : NULL),
900 vnode->volume);
901 if (IS_ERR(op)) {
902 ret = PTR_ERR(op);
903 goto out_unlock;
904 }
905
906 afs_op_set_vnode(op, 0, vnode);
907 op->setattr.attr = attr;
908
909 if (attr->ia_valid & ATTR_SIZE) {
910 op->file[0].dv_delta = 1;
911 op->file[0].set_size = true;
912 }
913 op->ctime = attr->ia_ctime;
914 op->file[0].update_ctime = 1;
915 op->file[0].modification = true;
916
917 op->ops = &afs_setattr_operation;
918 ret = afs_do_sync_operation(op);
919
920 out_unlock:
921 up_write(&vnode->validate_lock);
922 _leave(" = %d", ret);
923 return ret;
924 }
925