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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
28static const struct inode_operations afs_symlink_inode_operations = {
29 .get_link = page_get_link,
30};
31
32static 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 */
59static 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 */
152static 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 (op=%x)\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 op->debug_id);
213
214 vnode->invalid_before = status->data_version;
215 if (vnode->status.type == AFS_FTYPE_DIR) {
216 if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
217 afs_stat_v(vnode, n_inval);
218 } else {
219 set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
220 }
221 change_size = true;
222 } else if (vnode->status.type == AFS_FTYPE_DIR) {
223 /* Expected directory change is handled elsewhere so
224 * that we can locally edit the directory and save on a
225 * download.
226 */
227 if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
228 data_changed = false;
229 change_size = true;
230 }
231
232 if (data_changed) {
233 inode_set_iversion_raw(inode, status->data_version);
234
235 /* Only update the size if the data version jumped. If the
236 * file is being modified locally, then we might have our own
237 * idea of what the size should be that's not the same as
238 * what's on the server.
239 */
240 if (change_size) {
241 afs_set_i_size(vnode, status->size);
242 inode->i_ctime = t;
243 inode->i_atime = t;
244 }
245 }
246}
247
248/*
249 * Apply a callback to a vnode.
250 */
251static void afs_apply_callback(struct afs_operation *op,
252 struct afs_vnode_param *vp)
253{
254 struct afs_callback *cb = &vp->scb.callback;
255 struct afs_vnode *vnode = vp->vnode;
256
257 if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
258 vnode->cb_expires_at = cb->expires_at;
259 vnode->cb_server = op->server;
260 set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
261 }
262}
263
264/*
265 * Apply the received status and callback to an inode all in the same critical
266 * section to avoid races with afs_validate().
267 */
268void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
269{
270 struct afs_vnode *vnode = vp->vnode;
271
272 _enter("");
273
274 write_seqlock(&vnode->cb_lock);
275
276 if (vp->scb.have_error) {
277 /* A YFS server will return this from RemoveFile2 and AFS and
278 * YFS will return this from InlineBulkStatus.
279 */
280 if (vp->scb.status.abort_code == VNOVNODE) {
281 set_bit(AFS_VNODE_DELETED, &vnode->flags);
282 clear_nlink(&vnode->vfs_inode);
283 __afs_break_callback(vnode, afs_cb_break_for_deleted);
284 op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
285 }
286 } else if (vp->scb.have_status) {
287 if (vp->speculative &&
288 (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
289 vp->dv_before != vnode->status.data_version))
290 /* Ignore the result of a speculative bulk status fetch
291 * if it splits around a modification op, thereby
292 * appearing to regress the data version.
293 */
294 goto out;
295 afs_apply_status(op, vp);
296 if (vp->scb.have_cb)
297 afs_apply_callback(op, vp);
298 } else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
299 drop_nlink(&vnode->vfs_inode);
300 if (vnode->vfs_inode.i_nlink == 0) {
301 set_bit(AFS_VNODE_DELETED, &vnode->flags);
302 __afs_break_callback(vnode, afs_cb_break_for_deleted);
303 }
304 }
305
306out:
307 write_sequnlock(&vnode->cb_lock);
308
309 if (vp->scb.have_status)
310 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
311}
312
313static void afs_fetch_status_success(struct afs_operation *op)
314{
315 struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
316 struct afs_vnode *vnode = vp->vnode;
317 int ret;
318
319 if (vnode->vfs_inode.i_state & I_NEW) {
320 ret = afs_inode_init_from_status(op, vp, vnode);
321 op->error = ret;
322 if (ret == 0)
323 afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
324 } else {
325 afs_vnode_commit_status(op, vp);
326 }
327}
328
329const struct afs_operation_ops afs_fetch_status_operation = {
330 .issue_afs_rpc = afs_fs_fetch_status,
331 .issue_yfs_rpc = yfs_fs_fetch_status,
332 .success = afs_fetch_status_success,
333 .aborted = afs_check_for_remote_deletion,
334};
335
336/*
337 * Fetch file status from the volume.
338 */
339int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
340 afs_access_t *_caller_access)
341{
342 struct afs_operation *op;
343
344 _enter("%s,{%llx:%llu.%u,S=%lx}",
345 vnode->volume->name,
346 vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
347 vnode->flags);
348
349 op = afs_alloc_operation(key, vnode->volume);
350 if (IS_ERR(op))
351 return PTR_ERR(op);
352
353 afs_op_set_vnode(op, 0, vnode);
354
355 op->nr_files = 1;
356 op->ops = &afs_fetch_status_operation;
357 afs_begin_vnode_operation(op);
358 afs_wait_for_operation(op);
359
360 if (_caller_access)
361 *_caller_access = op->file[0].scb.status.caller_access;
362 return afs_put_operation(op);
363}
364
365/*
366 * ilookup() comparator
367 */
368int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
369{
370 struct afs_vnode *vnode = AFS_FS_I(inode);
371 struct afs_fid *fid = opaque;
372
373 return (fid->vnode == vnode->fid.vnode &&
374 fid->vnode_hi == vnode->fid.vnode_hi &&
375 fid->unique == vnode->fid.unique);
376}
377
378/*
379 * iget5() comparator
380 */
381static int afs_iget5_test(struct inode *inode, void *opaque)
382{
383 struct afs_vnode_param *vp = opaque;
384 //struct afs_vnode *vnode = AFS_FS_I(inode);
385
386 return afs_ilookup5_test_by_fid(inode, &vp->fid);
387}
388
389/*
390 * iget5() inode initialiser
391 */
392static int afs_iget5_set(struct inode *inode, void *opaque)
393{
394 struct afs_vnode_param *vp = opaque;
395 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
396 struct afs_vnode *vnode = AFS_FS_I(inode);
397
398 vnode->volume = as->volume;
399 vnode->fid = vp->fid;
400
401 /* YFS supports 96-bit vnode IDs, but Linux only supports
402 * 64-bit inode numbers.
403 */
404 inode->i_ino = vnode->fid.vnode;
405 inode->i_generation = vnode->fid.unique;
406 return 0;
407}
408
409/*
410 * Get a cache cookie for an inode.
411 */
412static void afs_get_inode_cache(struct afs_vnode *vnode)
413{
414#ifdef CONFIG_AFS_FSCACHE
415 struct {
416 u32 vnode_id;
417 u32 unique;
418 u32 vnode_id_ext[2]; /* Allow for a 96-bit key */
419 } __packed key;
420 struct afs_vnode_cache_aux aux;
421
422 if (vnode->status.type != AFS_FTYPE_FILE) {
423 vnode->cache = NULL;
424 return;
425 }
426
427 key.vnode_id = vnode->fid.vnode;
428 key.unique = vnode->fid.unique;
429 key.vnode_id_ext[0] = vnode->fid.vnode >> 32;
430 key.vnode_id_ext[1] = vnode->fid.vnode_hi;
431 aux.data_version = vnode->status.data_version;
432
433 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
434 &afs_vnode_cache_index_def,
435 &key, sizeof(key),
436 &aux, sizeof(aux),
437 vnode, vnode->status.size, true);
438#endif
439}
440
441/*
442 * inode retrieval
443 */
444struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
445{
446 struct afs_vnode_param *dvp = &op->file[0];
447 struct super_block *sb = dvp->vnode->vfs_inode.i_sb;
448 struct afs_vnode *vnode;
449 struct inode *inode;
450 int ret;
451
452 _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
453
454 inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
455 if (!inode) {
456 _leave(" = -ENOMEM");
457 return ERR_PTR(-ENOMEM);
458 }
459
460 vnode = AFS_FS_I(inode);
461
462 _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
463 inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
464
465 /* deal with an existing inode */
466 if (!(inode->i_state & I_NEW)) {
467 _leave(" = %p", inode);
468 return inode;
469 }
470
471 ret = afs_inode_init_from_status(op, vp, vnode);
472 if (ret < 0)
473 goto bad_inode;
474
475 afs_get_inode_cache(vnode);
476
477 /* success */
478 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
479 unlock_new_inode(inode);
480 _leave(" = %p", inode);
481 return inode;
482
483 /* failure */
484bad_inode:
485 iget_failed(inode);
486 _leave(" = %d [bad]", ret);
487 return ERR_PTR(ret);
488}
489
490static int afs_iget5_set_root(struct inode *inode, void *opaque)
491{
492 struct afs_super_info *as = AFS_FS_S(inode->i_sb);
493 struct afs_vnode *vnode = AFS_FS_I(inode);
494
495 vnode->volume = as->volume;
496 vnode->fid.vid = as->volume->vid,
497 vnode->fid.vnode = 1;
498 vnode->fid.unique = 1;
499 inode->i_ino = 1;
500 inode->i_generation = 1;
501 return 0;
502}
503
504/*
505 * Set up the root inode for a volume. This is always vnode 1, unique 1 within
506 * the volume.
507 */
508struct inode *afs_root_iget(struct super_block *sb, struct key *key)
509{
510 struct afs_super_info *as = AFS_FS_S(sb);
511 struct afs_operation *op;
512 struct afs_vnode *vnode;
513 struct inode *inode;
514 int ret;
515
516 _enter(",{%llx},,", as->volume->vid);
517
518 inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
519 if (!inode) {
520 _leave(" = -ENOMEM");
521 return ERR_PTR(-ENOMEM);
522 }
523
524 _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
525
526 BUG_ON(!(inode->i_state & I_NEW));
527
528 vnode = AFS_FS_I(inode);
529 vnode->cb_v_break = as->volume->cb_v_break,
530
531 op = afs_alloc_operation(key, as->volume);
532 if (IS_ERR(op)) {
533 ret = PTR_ERR(op);
534 goto error;
535 }
536
537 afs_op_set_vnode(op, 0, vnode);
538
539 op->nr_files = 1;
540 op->ops = &afs_fetch_status_operation;
541 ret = afs_do_sync_operation(op);
542 if (ret < 0)
543 goto error;
544
545 afs_get_inode_cache(vnode);
546
547 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
548 unlock_new_inode(inode);
549 _leave(" = %p", inode);
550 return inode;
551
552error:
553 iget_failed(inode);
554 _leave(" = %d [bad]", ret);
555 return ERR_PTR(ret);
556}
557
558/*
559 * mark the data attached to an inode as obsolete due to a write on the server
560 * - might also want to ditch all the outstanding writes and dirty pages
561 */
562static void afs_zap_data(struct afs_vnode *vnode)
563{
564 _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode);
565
566#ifdef CONFIG_AFS_FSCACHE
567 fscache_invalidate(vnode->cache);
568#endif
569
570 /* nuke all the non-dirty pages that aren't locked, mapped or being
571 * written back in a regular file and completely discard the pages in a
572 * directory or symlink */
573 if (S_ISREG(vnode->vfs_inode.i_mode))
574 invalidate_remote_inode(&vnode->vfs_inode);
575 else
576 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
577}
578
579/*
580 * Get the server reinit counter for a vnode's current server.
581 */
582static bool afs_get_s_break_rcu(struct afs_vnode *vnode, unsigned int *_s_break)
583{
584 struct afs_server_list *slist = rcu_dereference(vnode->volume->servers);
585 struct afs_server *server;
586 int i;
587
588 for (i = 0; i < slist->nr_servers; i++) {
589 server = slist->servers[i].server;
590 if (server == vnode->cb_server) {
591 *_s_break = READ_ONCE(server->cb_s_break);
592 return true;
593 }
594 }
595
596 return false;
597}
598
599/*
600 * Check the validity of a vnode/inode.
601 */
602bool afs_check_validity(struct afs_vnode *vnode)
603{
604 struct afs_volume *volume = vnode->volume;
605 enum afs_cb_break_reason need_clear = afs_cb_break_no_break;
606 time64_t now = ktime_get_real_seconds();
607 bool valid;
608 unsigned int cb_break, cb_s_break, cb_v_break;
609 int seq = 0;
610
611 do {
612 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
613 cb_v_break = READ_ONCE(volume->cb_v_break);
614 cb_break = vnode->cb_break;
615
616 if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) &&
617 afs_get_s_break_rcu(vnode, &cb_s_break)) {
618 if (vnode->cb_s_break != cb_s_break ||
619 vnode->cb_v_break != cb_v_break) {
620 vnode->cb_s_break = cb_s_break;
621 vnode->cb_v_break = cb_v_break;
622 need_clear = afs_cb_break_for_vsbreak;
623 valid = false;
624 } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
625 need_clear = afs_cb_break_for_zap;
626 valid = false;
627 } else if (vnode->cb_expires_at - 10 <= now) {
628 need_clear = afs_cb_break_for_lapsed;
629 valid = false;
630 } else {
631 valid = true;
632 }
633 } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
634 valid = true;
635 } else {
636 vnode->cb_v_break = cb_v_break;
637 valid = false;
638 }
639
640 } while (need_seqretry(&vnode->cb_lock, seq));
641
642 done_seqretry(&vnode->cb_lock, seq);
643
644 if (need_clear != afs_cb_break_no_break) {
645 write_seqlock(&vnode->cb_lock);
646 if (cb_break == vnode->cb_break)
647 __afs_break_callback(vnode, need_clear);
648 else
649 trace_afs_cb_miss(&vnode->fid, need_clear);
650 write_sequnlock(&vnode->cb_lock);
651 valid = false;
652 }
653
654 return valid;
655}
656
657/*
658 * validate a vnode/inode
659 * - there are several things we need to check
660 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
661 * symlink)
662 * - parent dir metadata changed (security changes)
663 * - dentry data changed (write, truncate)
664 * - dentry metadata changed (security changes)
665 */
666int afs_validate(struct afs_vnode *vnode, struct key *key)
667{
668 bool valid;
669 int ret;
670
671 _enter("{v={%llx:%llu} fl=%lx},%x",
672 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
673 key_serial(key));
674
675 rcu_read_lock();
676 valid = afs_check_validity(vnode);
677 rcu_read_unlock();
678
679 if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
680 clear_nlink(&vnode->vfs_inode);
681
682 if (valid)
683 goto valid;
684
685 down_write(&vnode->validate_lock);
686
687 /* if the promise has expired, we need to check the server again to get
688 * a new promise - note that if the (parent) directory's metadata was
689 * changed then the security may be different and we may no longer have
690 * access */
691 if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
692 _debug("not promised");
693 ret = afs_fetch_status(vnode, key, false, NULL);
694 if (ret < 0) {
695 if (ret == -ENOENT) {
696 set_bit(AFS_VNODE_DELETED, &vnode->flags);
697 ret = -ESTALE;
698 }
699 goto error_unlock;
700 }
701 _debug("new promise [fl=%lx]", vnode->flags);
702 }
703
704 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
705 _debug("file already deleted");
706 ret = -ESTALE;
707 goto error_unlock;
708 }
709
710 /* if the vnode's data version number changed then its contents are
711 * different */
712 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
713 afs_zap_data(vnode);
714 up_write(&vnode->validate_lock);
715valid:
716 _leave(" = 0");
717 return 0;
718
719error_unlock:
720 up_write(&vnode->validate_lock);
721 _leave(" = %d", ret);
722 return ret;
723}
724
725/*
726 * read the attributes of an inode
727 */
728int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,
729 struct kstat *stat, u32 request_mask, unsigned int query_flags)
730{
731 struct inode *inode = d_inode(path->dentry);
732 struct afs_vnode *vnode = AFS_FS_I(inode);
733 int seq = 0;
734
735 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
736
737 do {
738 read_seqbegin_or_lock(&vnode->cb_lock, &seq);
739 generic_fillattr(&init_user_ns, inode, stat);
740 if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
741 stat->nlink > 0)
742 stat->nlink -= 1;
743 } while (need_seqretry(&vnode->cb_lock, seq));
744
745 done_seqretry(&vnode->cb_lock, seq);
746 return 0;
747}
748
749/*
750 * discard an AFS inode
751 */
752int afs_drop_inode(struct inode *inode)
753{
754 _enter("");
755
756 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
757 return generic_delete_inode(inode);
758 else
759 return generic_drop_inode(inode);
760}
761
762/*
763 * clear an AFS inode
764 */
765void afs_evict_inode(struct inode *inode)
766{
767 struct afs_vnode *vnode;
768
769 vnode = AFS_FS_I(inode);
770
771 _enter("{%llx:%llu.%d}",
772 vnode->fid.vid,
773 vnode->fid.vnode,
774 vnode->fid.unique);
775
776 _debug("CLEAR INODE %p", inode);
777
778 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
779
780 truncate_inode_pages_final(&inode->i_data);
781 clear_inode(inode);
782
783 while (!list_empty(&vnode->wb_keys)) {
784 struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
785 struct afs_wb_key, vnode_link);
786 list_del(&wbk->vnode_link);
787 afs_put_wb_key(wbk);
788 }
789
790#ifdef CONFIG_AFS_FSCACHE
791 {
792 struct afs_vnode_cache_aux aux;
793
794 aux.data_version = vnode->status.data_version;
795 fscache_relinquish_cookie(vnode->cache, &aux,
796 test_bit(AFS_VNODE_DELETED, &vnode->flags));
797 vnode->cache = NULL;
798 }
799#endif
800
801 afs_prune_wb_keys(vnode);
802 afs_put_permits(rcu_access_pointer(vnode->permit_cache));
803 key_put(vnode->silly_key);
804 vnode->silly_key = NULL;
805 key_put(vnode->lock_key);
806 vnode->lock_key = NULL;
807 _leave("");
808}
809
810static void afs_setattr_success(struct afs_operation *op)
811{
812 struct afs_vnode_param *vp = &op->file[0];
813 struct inode *inode = &vp->vnode->vfs_inode;
814 loff_t old_i_size = i_size_read(inode);
815
816 op->setattr.old_i_size = old_i_size;
817 afs_vnode_commit_status(op, vp);
818 /* inode->i_size has now been changed. */
819
820 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
821 loff_t size = op->setattr.attr->ia_size;
822 if (size > old_i_size)
823 pagecache_isize_extended(inode, old_i_size, size);
824 }
825}
826
827static void afs_setattr_edit_file(struct afs_operation *op)
828{
829 struct afs_vnode_param *vp = &op->file[0];
830 struct inode *inode = &vp->vnode->vfs_inode;
831
832 if (op->setattr.attr->ia_valid & ATTR_SIZE) {
833 loff_t size = op->setattr.attr->ia_size;
834 loff_t i_size = op->setattr.old_i_size;
835
836 if (size < i_size)
837 truncate_pagecache(inode, size);
838 }
839}
840
841static const struct afs_operation_ops afs_setattr_operation = {
842 .issue_afs_rpc = afs_fs_setattr,
843 .issue_yfs_rpc = yfs_fs_setattr,
844 .success = afs_setattr_success,
845 .edit_dir = afs_setattr_edit_file,
846};
847
848/*
849 * set the attributes of an inode
850 */
851int afs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
852 struct iattr *attr)
853{
854 struct afs_operation *op;
855 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
856 int ret;
857
858 _enter("{%llx:%llu},{n=%pd},%x",
859 vnode->fid.vid, vnode->fid.vnode, dentry,
860 attr->ia_valid);
861
862 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
863 ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET |
864 ATTR_TOUCH))) {
865 _leave(" = 0 [unsupported]");
866 return 0;
867 }
868
869 if (attr->ia_valid & ATTR_SIZE) {
870 if (!S_ISREG(vnode->vfs_inode.i_mode))
871 return -EISDIR;
872
873 ret = inode_newsize_ok(&vnode->vfs_inode, attr->ia_size);
874 if (ret)
875 return ret;
876
877 if (attr->ia_size == i_size_read(&vnode->vfs_inode))
878 attr->ia_valid &= ~ATTR_SIZE;
879 }
880
881 /* flush any dirty data outstanding on a regular file */
882 if (S_ISREG(vnode->vfs_inode.i_mode))
883 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
884
885 /* Prevent any new writebacks from starting whilst we do this. */
886 down_write(&vnode->validate_lock);
887
888 op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
889 afs_file_key(attr->ia_file) : NULL),
890 vnode->volume);
891 if (IS_ERR(op)) {
892 ret = PTR_ERR(op);
893 goto out_unlock;
894 }
895
896 afs_op_set_vnode(op, 0, vnode);
897 op->setattr.attr = attr;
898
899 if (attr->ia_valid & ATTR_SIZE) {
900 op->file[0].dv_delta = 1;
901 op->file[0].set_size = true;
902 }
903 op->ctime = attr->ia_ctime;
904 op->file[0].update_ctime = 1;
905 op->file[0].modification = true;
906
907 op->ops = &afs_setattr_operation;
908 ret = afs_do_sync_operation(op);
909
910out_unlock:
911 up_write(&vnode->validate_lock);
912 _leave(" = %d", ret);
913 return ret;
914}
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 "internal.h"
25
26struct afs_iget_data {
27 struct afs_fid fid;
28 struct afs_volume *volume; /* volume on which resides */
29};
30
31/*
32 * map the AFS file status to the inode member variables
33 */
34static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
35{
36 struct inode *inode = AFS_VNODE_TO_I(vnode);
37
38 _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
39 vnode->status.type,
40 vnode->status.nlink,
41 (unsigned long long) vnode->status.size,
42 vnode->status.data_version,
43 vnode->status.mode);
44
45 switch (vnode->status.type) {
46 case AFS_FTYPE_FILE:
47 inode->i_mode = S_IFREG | vnode->status.mode;
48 inode->i_op = &afs_file_inode_operations;
49 inode->i_fop = &afs_file_operations;
50 break;
51 case AFS_FTYPE_DIR:
52 inode->i_mode = S_IFDIR | vnode->status.mode;
53 inode->i_op = &afs_dir_inode_operations;
54 inode->i_fop = &afs_dir_file_operations;
55 break;
56 case AFS_FTYPE_SYMLINK:
57 inode->i_mode = S_IFLNK | vnode->status.mode;
58 inode->i_op = &page_symlink_inode_operations;
59 break;
60 default:
61 printk("kAFS: AFS vnode with undefined type\n");
62 return -EBADMSG;
63 }
64
65#ifdef CONFIG_AFS_FSCACHE
66 if (vnode->status.size != inode->i_size)
67 fscache_attr_changed(vnode->cache);
68#endif
69
70 set_nlink(inode, vnode->status.nlink);
71 inode->i_uid = vnode->status.owner;
72 inode->i_gid = GLOBAL_ROOT_GID;
73 inode->i_size = vnode->status.size;
74 inode->i_ctime.tv_sec = vnode->status.mtime_server;
75 inode->i_ctime.tv_nsec = 0;
76 inode->i_atime = inode->i_mtime = inode->i_ctime;
77 inode->i_blocks = 0;
78 inode->i_generation = vnode->fid.unique;
79 inode->i_version = vnode->status.data_version;
80 inode->i_mapping->a_ops = &afs_fs_aops;
81
82 /* check to see whether a symbolic link is really a mountpoint */
83 if (vnode->status.type == AFS_FTYPE_SYMLINK) {
84 afs_mntpt_check_symlink(vnode, key);
85
86 if (test_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags)) {
87 inode->i_mode = S_IFDIR | vnode->status.mode;
88 inode->i_op = &afs_mntpt_inode_operations;
89 inode->i_fop = &afs_mntpt_file_operations;
90 }
91 }
92
93 return 0;
94}
95
96/*
97 * iget5() comparator
98 */
99static int afs_iget5_test(struct inode *inode, void *opaque)
100{
101 struct afs_iget_data *data = opaque;
102
103 return inode->i_ino == data->fid.vnode &&
104 inode->i_generation == data->fid.unique;
105}
106
107/*
108 * iget5() comparator for inode created by autocell operations
109 *
110 * These pseudo inodes don't match anything.
111 */
112static int afs_iget5_autocell_test(struct inode *inode, void *opaque)
113{
114 return 0;
115}
116
117/*
118 * iget5() inode initialiser
119 */
120static int afs_iget5_set(struct inode *inode, void *opaque)
121{
122 struct afs_iget_data *data = opaque;
123 struct afs_vnode *vnode = AFS_FS_I(inode);
124
125 inode->i_ino = data->fid.vnode;
126 inode->i_generation = data->fid.unique;
127 vnode->fid = data->fid;
128 vnode->volume = data->volume;
129
130 return 0;
131}
132
133/*
134 * inode retrieval for autocell
135 */
136struct inode *afs_iget_autocell(struct inode *dir, const char *dev_name,
137 int namesz, struct key *key)
138{
139 struct afs_iget_data data;
140 struct afs_super_info *as;
141 struct afs_vnode *vnode;
142 struct super_block *sb;
143 struct inode *inode;
144 static atomic_t afs_autocell_ino;
145
146 _enter("{%x:%u},%*.*s,",
147 AFS_FS_I(dir)->fid.vid, AFS_FS_I(dir)->fid.vnode,
148 namesz, namesz, dev_name ?: "");
149
150 sb = dir->i_sb;
151 as = sb->s_fs_info;
152 data.volume = as->volume;
153 data.fid.vid = as->volume->vid;
154 data.fid.unique = 0;
155 data.fid.vnode = 0;
156
157 inode = iget5_locked(sb, atomic_inc_return(&afs_autocell_ino),
158 afs_iget5_autocell_test, afs_iget5_set,
159 &data);
160 if (!inode) {
161 _leave(" = -ENOMEM");
162 return ERR_PTR(-ENOMEM);
163 }
164
165 _debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
166 inode, inode->i_ino, data.fid.vid, data.fid.vnode,
167 data.fid.unique);
168
169 vnode = AFS_FS_I(inode);
170
171 /* there shouldn't be an existing inode */
172 BUG_ON(!(inode->i_state & I_NEW));
173
174 inode->i_size = 0;
175 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
176 inode->i_op = &afs_autocell_inode_operations;
177 set_nlink(inode, 2);
178 inode->i_uid = GLOBAL_ROOT_UID;
179 inode->i_gid = GLOBAL_ROOT_GID;
180 inode->i_ctime.tv_sec = get_seconds();
181 inode->i_ctime.tv_nsec = 0;
182 inode->i_atime = inode->i_mtime = inode->i_ctime;
183 inode->i_blocks = 0;
184 inode->i_version = 0;
185 inode->i_generation = 0;
186
187 set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
188 set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
189 inode->i_flags |= S_AUTOMOUNT | S_NOATIME;
190 unlock_new_inode(inode);
191 _leave(" = %p", inode);
192 return inode;
193}
194
195/*
196 * inode retrieval
197 */
198struct inode *afs_iget(struct super_block *sb, struct key *key,
199 struct afs_fid *fid, struct afs_file_status *status,
200 struct afs_callback *cb)
201{
202 struct afs_iget_data data = { .fid = *fid };
203 struct afs_super_info *as;
204 struct afs_vnode *vnode;
205 struct inode *inode;
206 int ret;
207
208 _enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
209
210 as = sb->s_fs_info;
211 data.volume = as->volume;
212
213 inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
214 &data);
215 if (!inode) {
216 _leave(" = -ENOMEM");
217 return ERR_PTR(-ENOMEM);
218 }
219
220 _debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
221 inode, fid->vid, fid->vnode, fid->unique);
222
223 vnode = AFS_FS_I(inode);
224
225 /* deal with an existing inode */
226 if (!(inode->i_state & I_NEW)) {
227 _leave(" = %p", inode);
228 return inode;
229 }
230
231 if (!status) {
232 /* it's a remotely extant inode */
233 set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
234 ret = afs_vnode_fetch_status(vnode, NULL, key);
235 if (ret < 0)
236 goto bad_inode;
237 } else {
238 /* it's an inode we just created */
239 memcpy(&vnode->status, status, sizeof(vnode->status));
240
241 if (!cb) {
242 /* it's a symlink we just created (the fileserver
243 * didn't give us a callback) */
244 vnode->cb_version = 0;
245 vnode->cb_expiry = 0;
246 vnode->cb_type = 0;
247 vnode->cb_expires = get_seconds();
248 } else {
249 vnode->cb_version = cb->version;
250 vnode->cb_expiry = cb->expiry;
251 vnode->cb_type = cb->type;
252 vnode->cb_expires = vnode->cb_expiry + get_seconds();
253 }
254 }
255
256 /* set up caching before mapping the status, as map-status reads the
257 * first page of symlinks to see if they're really mountpoints */
258 inode->i_size = vnode->status.size;
259#ifdef CONFIG_AFS_FSCACHE
260 vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
261 &afs_vnode_cache_index_def,
262 vnode, true);
263#endif
264
265 ret = afs_inode_map_status(vnode, key);
266 if (ret < 0)
267 goto bad_inode;
268
269 /* success */
270 clear_bit(AFS_VNODE_UNSET, &vnode->flags);
271 inode->i_flags |= S_NOATIME;
272 unlock_new_inode(inode);
273 _leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
274 return inode;
275
276 /* failure */
277bad_inode:
278#ifdef CONFIG_AFS_FSCACHE
279 fscache_relinquish_cookie(vnode->cache, 0);
280 vnode->cache = NULL;
281#endif
282 iget_failed(inode);
283 _leave(" = %d [bad]", ret);
284 return ERR_PTR(ret);
285}
286
287/*
288 * mark the data attached to an inode as obsolete due to a write on the server
289 * - might also want to ditch all the outstanding writes and dirty pages
290 */
291void afs_zap_data(struct afs_vnode *vnode)
292{
293 _enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
294
295 /* nuke all the non-dirty pages that aren't locked, mapped or being
296 * written back in a regular file and completely discard the pages in a
297 * directory or symlink */
298 if (S_ISREG(vnode->vfs_inode.i_mode))
299 invalidate_remote_inode(&vnode->vfs_inode);
300 else
301 invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
302}
303
304/*
305 * validate a vnode/inode
306 * - there are several things we need to check
307 * - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
308 * symlink)
309 * - parent dir metadata changed (security changes)
310 * - dentry data changed (write, truncate)
311 * - dentry metadata changed (security changes)
312 */
313int afs_validate(struct afs_vnode *vnode, struct key *key)
314{
315 int ret;
316
317 _enter("{v={%x:%u} fl=%lx},%x",
318 vnode->fid.vid, vnode->fid.vnode, vnode->flags,
319 key_serial(key));
320
321 if (vnode->cb_promised &&
322 !test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
323 !test_bit(AFS_VNODE_MODIFIED, &vnode->flags) &&
324 !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
325 if (vnode->cb_expires < get_seconds() + 10) {
326 _debug("callback expired");
327 set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
328 } else {
329 goto valid;
330 }
331 }
332
333 if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
334 goto valid;
335
336 mutex_lock(&vnode->validate_lock);
337
338 /* if the promise has expired, we need to check the server again to get
339 * a new promise - note that if the (parent) directory's metadata was
340 * changed then the security may be different and we may no longer have
341 * access */
342 if (!vnode->cb_promised ||
343 test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) {
344 _debug("not promised");
345 ret = afs_vnode_fetch_status(vnode, NULL, key);
346 if (ret < 0)
347 goto error_unlock;
348 _debug("new promise [fl=%lx]", vnode->flags);
349 }
350
351 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
352 _debug("file already deleted");
353 ret = -ESTALE;
354 goto error_unlock;
355 }
356
357 /* if the vnode's data version number changed then its contents are
358 * different */
359 if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
360 afs_zap_data(vnode);
361
362 clear_bit(AFS_VNODE_MODIFIED, &vnode->flags);
363 mutex_unlock(&vnode->validate_lock);
364valid:
365 _leave(" = 0");
366 return 0;
367
368error_unlock:
369 mutex_unlock(&vnode->validate_lock);
370 _leave(" = %d", ret);
371 return ret;
372}
373
374/*
375 * read the attributes of an inode
376 */
377int afs_getattr(struct vfsmount *mnt, struct dentry *dentry,
378 struct kstat *stat)
379{
380 struct inode *inode;
381
382 inode = dentry->d_inode;
383
384 _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
385
386 generic_fillattr(inode, stat);
387 return 0;
388}
389
390/*
391 * discard an AFS inode
392 */
393int afs_drop_inode(struct inode *inode)
394{
395 _enter("");
396
397 if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
398 return generic_delete_inode(inode);
399 else
400 return generic_drop_inode(inode);
401}
402
403/*
404 * clear an AFS inode
405 */
406void afs_evict_inode(struct inode *inode)
407{
408 struct afs_permits *permits;
409 struct afs_vnode *vnode;
410
411 vnode = AFS_FS_I(inode);
412
413 _enter("{%x:%u.%d} v=%u x=%u t=%u }",
414 vnode->fid.vid,
415 vnode->fid.vnode,
416 vnode->fid.unique,
417 vnode->cb_version,
418 vnode->cb_expiry,
419 vnode->cb_type);
420
421 _debug("CLEAR INODE %p", inode);
422
423 ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
424
425 truncate_inode_pages_final(&inode->i_data);
426 clear_inode(inode);
427
428 afs_give_up_callback(vnode);
429
430 if (vnode->server) {
431 spin_lock(&vnode->server->fs_lock);
432 rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes);
433 spin_unlock(&vnode->server->fs_lock);
434 afs_put_server(vnode->server);
435 vnode->server = NULL;
436 }
437
438 ASSERT(list_empty(&vnode->writebacks));
439 ASSERT(!vnode->cb_promised);
440
441#ifdef CONFIG_AFS_FSCACHE
442 fscache_relinquish_cookie(vnode->cache, 0);
443 vnode->cache = NULL;
444#endif
445
446 mutex_lock(&vnode->permits_lock);
447 permits = vnode->permits;
448 rcu_assign_pointer(vnode->permits, NULL);
449 mutex_unlock(&vnode->permits_lock);
450 if (permits)
451 call_rcu(&permits->rcu, afs_zap_permits);
452
453 _leave("");
454}
455
456/*
457 * set the attributes of an inode
458 */
459int afs_setattr(struct dentry *dentry, struct iattr *attr)
460{
461 struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
462 struct key *key;
463 int ret;
464
465 _enter("{%x:%u},{n=%s},%x",
466 vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
467 attr->ia_valid);
468
469 if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
470 ATTR_MTIME))) {
471 _leave(" = 0 [unsupported]");
472 return 0;
473 }
474
475 /* flush any dirty data outstanding on a regular file */
476 if (S_ISREG(vnode->vfs_inode.i_mode)) {
477 filemap_write_and_wait(vnode->vfs_inode.i_mapping);
478 afs_writeback_all(vnode);
479 }
480
481 if (attr->ia_valid & ATTR_FILE) {
482 key = attr->ia_file->private_data;
483 } else {
484 key = afs_request_key(vnode->volume->cell);
485 if (IS_ERR(key)) {
486 ret = PTR_ERR(key);
487 goto error;
488 }
489 }
490
491 ret = afs_vnode_setattr(vnode, key, attr);
492 if (!(attr->ia_valid & ATTR_FILE))
493 key_put(key);
494
495error:
496 _leave(" = %d", ret);
497 return ret;
498}