xref: /linux/fs/afs/inode.c (revision 37c12fcb3c8e356825bbffb64c0158ccf8a7de94)
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 void afs_init_new_symlink(struct afs_vnode *vnode, struct afs_operation *op)
29 {
30 	size_t size = strlen(op->create.symlink) + 1;
31 	size_t dsize = 0;
32 	char *p;
33 
34 	if (netfs_alloc_folioq_buffer(NULL, &vnode->directory, &dsize, size,
35 				      mapping_gfp_mask(vnode->netfs.inode.i_mapping)) < 0)
36 		return;
37 
38 	vnode->directory_size = dsize;
39 	p = kmap_local_folio(folioq_folio(vnode->directory, 0), 0);
40 	memcpy(p, op->create.symlink, size);
41 	kunmap_local(p);
42 	set_bit(AFS_VNODE_DIR_READ, &vnode->flags);
43 	netfs_single_mark_inode_dirty(&vnode->netfs.inode);
44 }
45 
46 static void afs_put_link(void *arg)
47 {
48 	struct folio *folio = virt_to_folio(arg);
49 
50 	kunmap_local(arg);
51 	folio_put(folio);
52 }
53 
54 const char *afs_get_link(struct dentry *dentry, struct inode *inode,
55 			 struct delayed_call *callback)
56 {
57 	struct afs_vnode *vnode = AFS_FS_I(inode);
58 	struct folio *folio;
59 	char *content;
60 	ssize_t ret;
61 
62 	if (!dentry) {
63 		/* RCU pathwalk. */
64 		if (!test_bit(AFS_VNODE_DIR_READ, &vnode->flags) || !afs_check_validity(vnode))
65 			return ERR_PTR(-ECHILD);
66 		goto good;
67 	}
68 
69 	if (test_bit(AFS_VNODE_DIR_READ, &vnode->flags))
70 		goto fetch;
71 
72 	ret = afs_validate(vnode, NULL);
73 	if (ret < 0)
74 		return ERR_PTR(ret);
75 
76 	if (!test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
77 	    test_bit(AFS_VNODE_DIR_READ, &vnode->flags))
78 		goto good;
79 
80 fetch:
81 	ret = afs_read_single(vnode, NULL);
82 	if (ret < 0)
83 		return ERR_PTR(ret);
84 	set_bit(AFS_VNODE_DIR_READ, &vnode->flags);
85 
86 good:
87 	folio = folioq_folio(vnode->directory, 0);
88 	folio_get(folio);
89 	content = kmap_local_folio(folio, 0);
90 	set_delayed_call(callback, afs_put_link, content);
91 	return content;
92 }
93 
94 int afs_readlink(struct dentry *dentry, char __user *buffer, int buflen)
95 {
96 	DEFINE_DELAYED_CALL(done);
97 	const char *content;
98 	int len;
99 
100 	content = afs_get_link(dentry, d_inode(dentry), &done);
101 	if (IS_ERR(content)) {
102 		do_delayed_call(&done);
103 		return PTR_ERR(content);
104 	}
105 
106 	len = umin(strlen(content), buflen);
107 	if (copy_to_user(buffer, content, len))
108 		len = -EFAULT;
109 	do_delayed_call(&done);
110 	return len;
111 }
112 
113 static const struct inode_operations afs_symlink_inode_operations = {
114 	.get_link	= afs_get_link,
115 	.readlink	= afs_readlink,
116 };
117 
118 static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode)
119 {
120 	static unsigned long once_only;
121 
122 	pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type);
123 	pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n",
124 		vnode->status.abort_code,
125 		vnode->status.mode,
126 		vnode->status.size,
127 		vnode->status.data_version);
128 	pr_warn("kAFS: vnode %llx:%llx:%x\n",
129 		vnode->fid.vid,
130 		vnode->fid.vnode,
131 		vnode->fid.unique);
132 	if (parent_vnode)
133 		pr_warn("kAFS: dir %llx:%llx:%x\n",
134 			parent_vnode->fid.vid,
135 			parent_vnode->fid.vnode,
136 			parent_vnode->fid.unique);
137 
138 	if (!test_and_set_bit(0, &once_only))
139 		dump_stack();
140 }
141 
142 /*
143  * Set parameters for the netfs library
144  */
145 static void afs_set_netfs_context(struct afs_vnode *vnode)
146 {
147 	netfs_inode_init(&vnode->netfs, &afs_req_ops, true);
148 }
149 
150 /*
151  * Initialise an inode from the vnode status.
152  */
153 static int afs_inode_init_from_status(struct afs_operation *op,
154 				      struct afs_vnode_param *vp,
155 				      struct afs_vnode *vnode)
156 {
157 	struct afs_file_status *status = &vp->scb.status;
158 	struct inode *inode = AFS_VNODE_TO_I(vnode);
159 	struct timespec64 t;
160 
161 	_enter("{%llx:%llu.%u} %s",
162 	       vp->fid.vid, vp->fid.vnode, vp->fid.unique,
163 	       op->type ? op->type->name : "???");
164 
165 	_debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
166 	       status->type,
167 	       status->nlink,
168 	       (unsigned long long) status->size,
169 	       status->data_version,
170 	       status->mode);
171 
172 	write_seqlock(&vnode->cb_lock);
173 
174 	vnode->cb_v_check = op->cb_v_break;
175 	vnode->status = *status;
176 
177 	t = status->mtime_client;
178 	inode_set_ctime_to_ts(inode, t);
179 	inode_set_mtime_to_ts(inode, t);
180 	inode_set_atime_to_ts(inode, t);
181 	inode->i_flags |= S_NOATIME;
182 	inode->i_uid = make_kuid(&init_user_ns, status->owner);
183 	inode->i_gid = make_kgid(&init_user_ns, status->group);
184 	set_nlink(&vnode->netfs.inode, status->nlink);
185 
186 	switch (status->type) {
187 	case AFS_FTYPE_FILE:
188 		inode->i_mode	= S_IFREG | (status->mode & S_IALLUGO);
189 		inode->i_op	= &afs_file_inode_operations;
190 		inode->i_fop	= &afs_file_operations;
191 		inode->i_mapping->a_ops	= &afs_file_aops;
192 		mapping_set_large_folios(inode->i_mapping);
193 		break;
194 	case AFS_FTYPE_DIR:
195 		inode->i_mode	= S_IFDIR |  (status->mode & S_IALLUGO);
196 		inode->i_op	= &afs_dir_inode_operations;
197 		inode->i_fop	= &afs_dir_file_operations;
198 		inode->i_mapping->a_ops	= &afs_dir_aops;
199 		__set_bit(NETFS_ICTX_SINGLE_NO_UPLOAD, &vnode->netfs.flags);
200 		/* Assume locally cached directory data will be valid. */
201 		__set_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
202 		break;
203 	case AFS_FTYPE_SYMLINK:
204 		/* Symlinks with a mode of 0644 are actually mountpoints. */
205 		if ((status->mode & 0777) == 0644) {
206 			inode->i_flags |= S_AUTOMOUNT;
207 
208 			set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
209 
210 			inode->i_mode	= S_IFDIR | 0555;
211 			inode->i_op	= &afs_mntpt_inode_operations;
212 			inode->i_fop	= &afs_mntpt_file_operations;
213 		} else {
214 			inode->i_mode	= S_IFLNK | status->mode;
215 			inode->i_op	= &afs_symlink_inode_operations;
216 		}
217 		inode->i_mapping->a_ops	= &afs_dir_aops;
218 		inode_nohighmem(inode);
219 		mapping_set_release_always(inode->i_mapping);
220 		break;
221 	default:
222 		dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL);
223 		write_sequnlock(&vnode->cb_lock);
224 		return afs_protocol_error(NULL, afs_eproto_file_type);
225 	}
226 
227 	afs_set_i_size(vnode, status->size);
228 	afs_set_netfs_context(vnode);
229 
230 	vnode->invalid_before	= status->data_version;
231 	trace_afs_set_dv(vnode, status->data_version);
232 	inode_set_iversion_raw(&vnode->netfs.inode, status->data_version);
233 
234 	if (!vp->scb.have_cb) {
235 		/* it's a symlink we just created (the fileserver
236 		 * didn't give us a callback) */
237 		afs_clear_cb_promise(vnode, afs_cb_promise_set_new_symlink);
238 	} else {
239 		vnode->cb_server = op->server;
240 		afs_set_cb_promise(vnode, vp->scb.callback.expires_at,
241 				   afs_cb_promise_set_new_inode);
242 	}
243 
244 	write_sequnlock(&vnode->cb_lock);
245 	return 0;
246 }
247 
248 /*
249  * Update the core inode struct from a returned status record.
250  */
251 static void afs_apply_status(struct afs_operation *op,
252 			     struct afs_vnode_param *vp)
253 {
254 	struct afs_file_status *status = &vp->scb.status;
255 	struct afs_vnode *vnode = vp->vnode;
256 	struct inode *inode = &vnode->netfs.inode;
257 	struct timespec64 t;
258 	umode_t mode;
259 	bool unexpected_jump = false;
260 	bool data_changed = false;
261 	bool change_size = vp->set_size;
262 
263 	_enter("{%llx:%llu.%u} %s",
264 	       vp->fid.vid, vp->fid.vnode, vp->fid.unique,
265 	       op->type ? op->type->name : "???");
266 
267 	BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags));
268 
269 	if (status->type != vnode->status.type) {
270 		pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n",
271 			vnode->fid.vid,
272 			vnode->fid.vnode,
273 			vnode->fid.unique,
274 			status->type, vnode->status.type);
275 		afs_protocol_error(NULL, afs_eproto_bad_status);
276 		return;
277 	}
278 
279 	if (status->nlink != vnode->status.nlink)
280 		set_nlink(inode, status->nlink);
281 
282 	if (status->owner != vnode->status.owner)
283 		inode->i_uid = make_kuid(&init_user_ns, status->owner);
284 
285 	if (status->group != vnode->status.group)
286 		inode->i_gid = make_kgid(&init_user_ns, status->group);
287 
288 	if (status->mode != vnode->status.mode) {
289 		mode = inode->i_mode;
290 		mode &= ~S_IALLUGO;
291 		mode |= status->mode & S_IALLUGO;
292 		WRITE_ONCE(inode->i_mode, mode);
293 	}
294 
295 	t = status->mtime_client;
296 	inode_set_mtime_to_ts(inode, t);
297 	if (vp->update_ctime)
298 		inode_set_ctime_to_ts(inode, op->ctime);
299 
300 	if (vnode->status.data_version != status->data_version) {
301 		trace_afs_set_dv(vnode, status->data_version);
302 		data_changed = true;
303 	}
304 
305 	vnode->status = *status;
306 
307 	if (vp->dv_before + vp->dv_delta != status->data_version) {
308 		trace_afs_dv_mismatch(vnode, vp->dv_before, vp->dv_delta,
309 				      status->data_version);
310 
311 		if (vnode->cb_ro_snapshot == atomic_read(&vnode->volume->cb_ro_snapshot) &&
312 		    atomic64_read(&vnode->cb_expires_at) != AFS_NO_CB_PROMISE)
313 			pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s (op=%x)\n",
314 				vnode->fid.vid, vnode->fid.vnode,
315 				(unsigned long long)vp->dv_before + vp->dv_delta,
316 				(unsigned long long)status->data_version,
317 				op->type ? op->type->name : "???",
318 				op->debug_id);
319 
320 		vnode->invalid_before = status->data_version;
321 		if (vnode->status.type == AFS_FTYPE_DIR)
322 			afs_invalidate_dir(vnode, afs_dir_invalid_dv_mismatch);
323 		else
324 			set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags);
325 		change_size = true;
326 		data_changed = true;
327 		unexpected_jump = true;
328 	} else if (vnode->status.type == AFS_FTYPE_DIR) {
329 		/* Expected directory change is handled elsewhere so
330 		 * that we can locally edit the directory and save on a
331 		 * download.
332 		 */
333 		if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
334 			data_changed = false;
335 		change_size = true;
336 	}
337 
338 	if (data_changed) {
339 		inode_set_iversion_raw(inode, status->data_version);
340 
341 		/* Only update the size if the data version jumped.  If the
342 		 * file is being modified locally, then we might have our own
343 		 * idea of what the size should be that's not the same as
344 		 * what's on the server.
345 		 */
346 		vnode->netfs.remote_i_size = status->size;
347 		if (change_size || status->size > i_size_read(inode)) {
348 			afs_set_i_size(vnode, status->size);
349 			if (unexpected_jump)
350 				vnode->netfs.zero_point = status->size;
351 			inode_set_ctime_to_ts(inode, t);
352 			inode_set_atime_to_ts(inode, t);
353 		}
354 		if (op->ops == &afs_fetch_data_operation)
355 			op->fetch.subreq->rreq->i_size = status->size;
356 	}
357 }
358 
359 /*
360  * Apply a callback to a vnode.
361  */
362 static void afs_apply_callback(struct afs_operation *op,
363 			       struct afs_vnode_param *vp)
364 {
365 	struct afs_callback *cb = &vp->scb.callback;
366 	struct afs_vnode *vnode = vp->vnode;
367 
368 	if (!afs_cb_is_broken(vp->cb_break_before, vnode)) {
369 		if (op->volume->type == AFSVL_RWVOL)
370 			vnode->cb_server = op->server;
371 		afs_set_cb_promise(vnode, cb->expires_at, afs_cb_promise_set_apply_cb);
372 	}
373 }
374 
375 /*
376  * Apply the received status and callback to an inode all in the same critical
377  * section to avoid races with afs_validate().
378  */
379 void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp)
380 {
381 	struct afs_vnode *vnode = vp->vnode;
382 
383 	_enter("");
384 
385 	write_seqlock(&vnode->cb_lock);
386 
387 	if (vp->scb.have_error) {
388 		/* A YFS server will return this from RemoveFile2 and AFS and
389 		 * YFS will return this from InlineBulkStatus.
390 		 */
391 		if (vp->scb.status.abort_code == VNOVNODE) {
392 			set_bit(AFS_VNODE_DELETED, &vnode->flags);
393 			clear_nlink(&vnode->netfs.inode);
394 			__afs_break_callback(vnode, afs_cb_break_for_deleted);
395 			op->flags &= ~AFS_OPERATION_DIR_CONFLICT;
396 		}
397 	} else if (vp->scb.have_status) {
398 		if (vp->speculative &&
399 		    (test_bit(AFS_VNODE_MODIFYING, &vnode->flags) ||
400 		     vp->dv_before != vnode->status.data_version))
401 			/* Ignore the result of a speculative bulk status fetch
402 			 * if it splits around a modification op, thereby
403 			 * appearing to regress the data version.
404 			 */
405 			goto out;
406 		afs_apply_status(op, vp);
407 		if (vp->scb.have_cb)
408 			afs_apply_callback(op, vp);
409 	} else if (vp->op_unlinked && !(op->flags & AFS_OPERATION_DIR_CONFLICT)) {
410 		drop_nlink(&vnode->netfs.inode);
411 		if (vnode->netfs.inode.i_nlink == 0) {
412 			set_bit(AFS_VNODE_DELETED, &vnode->flags);
413 			__afs_break_callback(vnode, afs_cb_break_for_deleted);
414 		}
415 	}
416 
417 out:
418 	write_sequnlock(&vnode->cb_lock);
419 
420 	if (vp->scb.have_status)
421 		afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
422 }
423 
424 static void afs_fetch_status_success(struct afs_operation *op)
425 {
426 	struct afs_vnode_param *vp = &op->file[op->fetch_status.which];
427 	struct afs_vnode *vnode = vp->vnode;
428 	int ret;
429 
430 	if (vnode->netfs.inode.i_state & I_NEW) {
431 		ret = afs_inode_init_from_status(op, vp, vnode);
432 		afs_op_set_error(op, ret);
433 		if (ret == 0)
434 			afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb);
435 	} else {
436 		afs_vnode_commit_status(op, vp);
437 	}
438 }
439 
440 const struct afs_operation_ops afs_fetch_status_operation = {
441 	.issue_afs_rpc	= afs_fs_fetch_status,
442 	.issue_yfs_rpc	= yfs_fs_fetch_status,
443 	.success	= afs_fetch_status_success,
444 	.aborted	= afs_check_for_remote_deletion,
445 };
446 
447 /*
448  * Fetch file status from the volume.
449  */
450 int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new,
451 		     afs_access_t *_caller_access)
452 {
453 	struct afs_operation *op;
454 
455 	_enter("%s,{%llx:%llu.%u,S=%lx}",
456 	       vnode->volume->name,
457 	       vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
458 	       vnode->flags);
459 
460 	op = afs_alloc_operation(key, vnode->volume);
461 	if (IS_ERR(op))
462 		return PTR_ERR(op);
463 
464 	afs_op_set_vnode(op, 0, vnode);
465 
466 	op->nr_files	= 1;
467 	op->ops		= &afs_fetch_status_operation;
468 	afs_begin_vnode_operation(op);
469 	afs_wait_for_operation(op);
470 
471 	if (_caller_access)
472 		*_caller_access = op->file[0].scb.status.caller_access;
473 	return afs_put_operation(op);
474 }
475 
476 /*
477  * ilookup() comparator
478  */
479 int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque)
480 {
481 	struct afs_vnode *vnode = AFS_FS_I(inode);
482 	struct afs_fid *fid = opaque;
483 
484 	return (fid->vnode == vnode->fid.vnode &&
485 		fid->vnode_hi == vnode->fid.vnode_hi &&
486 		fid->unique == vnode->fid.unique);
487 }
488 
489 /*
490  * iget5() comparator
491  */
492 static int afs_iget5_test(struct inode *inode, void *opaque)
493 {
494 	struct afs_vnode_param *vp = opaque;
495 	//struct afs_vnode *vnode = AFS_FS_I(inode);
496 
497 	return afs_ilookup5_test_by_fid(inode, &vp->fid);
498 }
499 
500 /*
501  * iget5() inode initialiser
502  */
503 static int afs_iget5_set(struct inode *inode, void *opaque)
504 {
505 	struct afs_vnode_param *vp = opaque;
506 	struct afs_super_info *as = AFS_FS_S(inode->i_sb);
507 	struct afs_vnode *vnode = AFS_FS_I(inode);
508 
509 	vnode->volume		= as->volume;
510 	vnode->fid		= vp->fid;
511 
512 	/* YFS supports 96-bit vnode IDs, but Linux only supports
513 	 * 64-bit inode numbers.
514 	 */
515 	inode->i_ino		= vnode->fid.vnode;
516 	inode->i_generation	= vnode->fid.unique;
517 	return 0;
518 }
519 
520 /*
521  * Get a cache cookie for an inode.
522  */
523 static void afs_get_inode_cache(struct afs_vnode *vnode)
524 {
525 #ifdef CONFIG_AFS_FSCACHE
526 	struct {
527 		__be32 vnode_id;
528 		__be32 unique;
529 		__be32 vnode_id_ext[2];	/* Allow for a 96-bit key */
530 	} __packed key;
531 	struct afs_vnode_cache_aux aux;
532 
533 	if (vnode->status.type != AFS_FTYPE_FILE &&
534 	    vnode->status.type != AFS_FTYPE_DIR &&
535 	    vnode->status.type != AFS_FTYPE_SYMLINK) {
536 		vnode->netfs.cache = NULL;
537 		return;
538 	}
539 
540 	key.vnode_id		= htonl(vnode->fid.vnode);
541 	key.unique		= htonl(vnode->fid.unique);
542 	key.vnode_id_ext[0]	= htonl(vnode->fid.vnode >> 32);
543 	key.vnode_id_ext[1]	= htonl(vnode->fid.vnode_hi);
544 	afs_set_cache_aux(vnode, &aux);
545 
546 	afs_vnode_set_cache(vnode,
547 			    fscache_acquire_cookie(
548 				    vnode->volume->cache,
549 				    vnode->status.type == AFS_FTYPE_FILE ?
550 				    0 : FSCACHE_ADV_SINGLE_CHUNK,
551 				    &key, sizeof(key),
552 				    &aux, sizeof(aux),
553 				    i_size_read(&vnode->netfs.inode)));
554 #endif
555 }
556 
557 /*
558  * inode retrieval
559  */
560 struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp)
561 {
562 	struct afs_vnode_param *dvp = &op->file[0];
563 	struct super_block *sb = dvp->vnode->netfs.inode.i_sb;
564 	struct afs_vnode *vnode;
565 	struct inode *inode;
566 	int ret;
567 
568 	_enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique);
569 
570 	inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp);
571 	if (!inode) {
572 		_leave(" = -ENOMEM");
573 		return ERR_PTR(-ENOMEM);
574 	}
575 
576 	vnode = AFS_FS_I(inode);
577 
578 	_debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }",
579 	       inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);
580 
581 	/* deal with an existing inode */
582 	if (!(inode->i_state & I_NEW)) {
583 		_leave(" = %p", inode);
584 		return inode;
585 	}
586 
587 	ret = afs_inode_init_from_status(op, vp, vnode);
588 	if (ret < 0)
589 		goto bad_inode;
590 
591 	afs_get_inode_cache(vnode);
592 
593 	/* success */
594 	clear_bit(AFS_VNODE_UNSET, &vnode->flags);
595 	unlock_new_inode(inode);
596 	_leave(" = %p", inode);
597 	return inode;
598 
599 	/* failure */
600 bad_inode:
601 	iget_failed(inode);
602 	_leave(" = %d [bad]", ret);
603 	return ERR_PTR(ret);
604 }
605 
606 static int afs_iget5_set_root(struct inode *inode, void *opaque)
607 {
608 	struct afs_super_info *as = AFS_FS_S(inode->i_sb);
609 	struct afs_vnode *vnode = AFS_FS_I(inode);
610 
611 	vnode->volume		= as->volume;
612 	vnode->fid.vid		= as->volume->vid;
613 	vnode->fid.vnode	= 1;
614 	vnode->fid.unique	= 1;
615 	inode->i_ino		= 1;
616 	inode->i_generation	= 1;
617 	return 0;
618 }
619 
620 /*
621  * Set up the root inode for a volume.  This is always vnode 1, unique 1 within
622  * the volume.
623  */
624 struct inode *afs_root_iget(struct super_block *sb, struct key *key)
625 {
626 	struct afs_super_info *as = AFS_FS_S(sb);
627 	struct afs_operation *op;
628 	struct afs_vnode *vnode;
629 	struct inode *inode;
630 	int ret;
631 
632 	_enter(",{%llx},,", as->volume->vid);
633 
634 	inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL);
635 	if (!inode) {
636 		_leave(" = -ENOMEM");
637 		return ERR_PTR(-ENOMEM);
638 	}
639 
640 	_debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid);
641 
642 	BUG_ON(!(inode->i_state & I_NEW));
643 
644 	vnode = AFS_FS_I(inode);
645 	vnode->cb_v_check = atomic_read(&as->volume->cb_v_break);
646 	afs_set_netfs_context(vnode);
647 
648 	op = afs_alloc_operation(key, as->volume);
649 	if (IS_ERR(op)) {
650 		ret = PTR_ERR(op);
651 		goto error;
652 	}
653 
654 	afs_op_set_vnode(op, 0, vnode);
655 
656 	op->nr_files	= 1;
657 	op->ops		= &afs_fetch_status_operation;
658 	ret = afs_do_sync_operation(op);
659 	if (ret < 0)
660 		goto error;
661 
662 	afs_get_inode_cache(vnode);
663 
664 	clear_bit(AFS_VNODE_UNSET, &vnode->flags);
665 	unlock_new_inode(inode);
666 	_leave(" = %p", inode);
667 	return inode;
668 
669 error:
670 	iget_failed(inode);
671 	_leave(" = %d [bad]", ret);
672 	return ERR_PTR(ret);
673 }
674 
675 /*
676  * read the attributes of an inode
677  */
678 int afs_getattr(struct mnt_idmap *idmap, const struct path *path,
679 		struct kstat *stat, u32 request_mask, unsigned int query_flags)
680 {
681 	struct inode *inode = d_inode(path->dentry);
682 	struct afs_vnode *vnode = AFS_FS_I(inode);
683 	struct key *key;
684 	int ret, seq;
685 
686 	_enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
687 
688 	if (vnode->volume &&
689 	    !(query_flags & AT_STATX_DONT_SYNC) &&
690 	    atomic64_read(&vnode->cb_expires_at) == AFS_NO_CB_PROMISE) {
691 		key = afs_request_key(vnode->volume->cell);
692 		if (IS_ERR(key))
693 			return PTR_ERR(key);
694 		ret = afs_validate(vnode, key);
695 		key_put(key);
696 		if (ret < 0)
697 			return ret;
698 	}
699 
700 	do {
701 		seq = read_seqbegin(&vnode->cb_lock);
702 		generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
703 		if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
704 		    stat->nlink > 0)
705 			stat->nlink -= 1;
706 
707 		/* Lie about the size of directories.  We maintain a locally
708 		 * edited copy and may make different allocation decisions on
709 		 * it, but we need to give userspace the server's size.
710 		 */
711 		if (S_ISDIR(inode->i_mode))
712 			stat->size = vnode->netfs.remote_i_size;
713 	} while (read_seqretry(&vnode->cb_lock, seq));
714 
715 	return 0;
716 }
717 
718 /*
719  * discard an AFS inode
720  */
721 int afs_drop_inode(struct inode *inode)
722 {
723 	_enter("");
724 
725 	if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
726 		return generic_delete_inode(inode);
727 	else
728 		return generic_drop_inode(inode);
729 }
730 
731 /*
732  * clear an AFS inode
733  */
734 void afs_evict_inode(struct inode *inode)
735 {
736 	struct afs_vnode_cache_aux aux;
737 	struct afs_super_info *sbi = AFS_FS_S(inode->i_sb);
738 	struct afs_vnode *vnode = AFS_FS_I(inode);
739 
740 	_enter("{%llx:%llu.%d}",
741 	       vnode->fid.vid,
742 	       vnode->fid.vnode,
743 	       vnode->fid.unique);
744 
745 	_debug("CLEAR INODE %p", inode);
746 
747 	ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
748 
749 	if ((S_ISDIR(inode->i_mode) ||
750 	     S_ISLNK(inode->i_mode)) &&
751 	    (inode->i_state & I_DIRTY) &&
752 	    !sbi->dyn_root) {
753 		struct writeback_control wbc = {
754 			.sync_mode = WB_SYNC_ALL,
755 			.for_sync = true,
756 			.range_end = LLONG_MAX,
757 		};
758 
759 		afs_single_writepages(inode->i_mapping, &wbc);
760 	}
761 
762 	netfs_wait_for_outstanding_io(inode);
763 	truncate_inode_pages_final(&inode->i_data);
764 	netfs_free_folioq_buffer(vnode->directory);
765 
766 	afs_set_cache_aux(vnode, &aux);
767 	netfs_clear_inode_writeback(inode, &aux);
768 	clear_inode(inode);
769 
770 	while (!list_empty(&vnode->wb_keys)) {
771 		struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
772 						    struct afs_wb_key, vnode_link);
773 		list_del(&wbk->vnode_link);
774 		afs_put_wb_key(wbk);
775 	}
776 
777 	fscache_relinquish_cookie(afs_vnode_cache(vnode),
778 				  test_bit(AFS_VNODE_DELETED, &vnode->flags));
779 
780 	afs_prune_wb_keys(vnode);
781 	afs_put_permits(rcu_access_pointer(vnode->permit_cache));
782 	key_put(vnode->silly_key);
783 	vnode->silly_key = NULL;
784 	key_put(vnode->lock_key);
785 	vnode->lock_key = NULL;
786 	_leave("");
787 }
788 
789 static void afs_setattr_success(struct afs_operation *op)
790 {
791 	struct afs_vnode_param *vp = &op->file[0];
792 	struct inode *inode = &vp->vnode->netfs.inode;
793 	loff_t old_i_size = i_size_read(inode);
794 
795 	op->setattr.old_i_size = old_i_size;
796 	afs_vnode_commit_status(op, vp);
797 	/* inode->i_size has now been changed. */
798 
799 	if (op->setattr.attr->ia_valid & ATTR_SIZE) {
800 		loff_t size = op->setattr.attr->ia_size;
801 		if (size > old_i_size)
802 			pagecache_isize_extended(inode, old_i_size, size);
803 	}
804 }
805 
806 static void afs_setattr_edit_file(struct afs_operation *op)
807 {
808 	struct afs_vnode_param *vp = &op->file[0];
809 	struct afs_vnode *vnode = vp->vnode;
810 	struct inode *inode = &vnode->netfs.inode;
811 
812 	if (op->setattr.attr->ia_valid & ATTR_SIZE) {
813 		loff_t size = op->setattr.attr->ia_size;
814 		loff_t old = op->setattr.old_i_size;
815 
816 		/* Note: inode->i_size was updated by afs_apply_status() inside
817 		 * the I/O and callback locks.
818 		 */
819 
820 		if (size != old) {
821 			truncate_pagecache(inode, size);
822 			netfs_resize_file(&vnode->netfs, size, true);
823 			fscache_resize_cookie(afs_vnode_cache(vnode), size);
824 		}
825 	}
826 }
827 
828 static const struct afs_operation_ops afs_setattr_operation = {
829 	.issue_afs_rpc	= afs_fs_setattr,
830 	.issue_yfs_rpc	= yfs_fs_setattr,
831 	.success	= afs_setattr_success,
832 	.edit_dir	= afs_setattr_edit_file,
833 };
834 
835 /*
836  * set the attributes of an inode
837  */
838 int afs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
839 		struct iattr *attr)
840 {
841 	const unsigned int supported =
842 		ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
843 		ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET | ATTR_TOUCH;
844 	struct afs_operation *op;
845 	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
846 	struct inode *inode = &vnode->netfs.inode;
847 	loff_t i_size;
848 	int ret;
849 
850 	_enter("{%llx:%llu},{n=%pd},%x",
851 	       vnode->fid.vid, vnode->fid.vnode, dentry,
852 	       attr->ia_valid);
853 
854 	if (!(attr->ia_valid & supported)) {
855 		_leave(" = 0 [unsupported]");
856 		return 0;
857 	}
858 
859 	i_size = i_size_read(inode);
860 	if (attr->ia_valid & ATTR_SIZE) {
861 		if (!S_ISREG(inode->i_mode))
862 			return -EISDIR;
863 
864 		ret = inode_newsize_ok(inode, attr->ia_size);
865 		if (ret)
866 			return ret;
867 
868 		if (attr->ia_size == i_size)
869 			attr->ia_valid &= ~ATTR_SIZE;
870 	}
871 
872 	fscache_use_cookie(afs_vnode_cache(vnode), true);
873 
874 	/* Prevent any new writebacks from starting whilst we do this. */
875 	down_write(&vnode->validate_lock);
876 
877 	if ((attr->ia_valid & ATTR_SIZE) && S_ISREG(inode->i_mode)) {
878 		loff_t size = attr->ia_size;
879 
880 		/* Wait for any outstanding writes to the server to complete */
881 		loff_t from = min(size, i_size);
882 		loff_t to = max(size, i_size);
883 		ret = filemap_fdatawait_range(inode->i_mapping, from, to);
884 		if (ret < 0)
885 			goto out_unlock;
886 
887 		/* Don't talk to the server if we're just shortening in-memory
888 		 * writes that haven't gone to the server yet.
889 		 */
890 		if (!(attr->ia_valid & (supported & ~ATTR_SIZE & ~ATTR_MTIME)) &&
891 		    attr->ia_size < i_size &&
892 		    attr->ia_size > vnode->netfs.remote_i_size) {
893 			truncate_setsize(inode, attr->ia_size);
894 			netfs_resize_file(&vnode->netfs, size, false);
895 			fscache_resize_cookie(afs_vnode_cache(vnode),
896 					      attr->ia_size);
897 			ret = 0;
898 			goto out_unlock;
899 		}
900 	}
901 
902 	op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
903 				  afs_file_key(attr->ia_file) : NULL),
904 				 vnode->volume);
905 	if (IS_ERR(op)) {
906 		ret = PTR_ERR(op);
907 		goto out_unlock;
908 	}
909 
910 	afs_op_set_vnode(op, 0, vnode);
911 	op->setattr.attr = attr;
912 
913 	if (attr->ia_valid & ATTR_SIZE) {
914 		op->file[0].dv_delta = 1;
915 		op->file[0].set_size = true;
916 	}
917 	op->ctime = attr->ia_ctime;
918 	op->file[0].update_ctime = 1;
919 	op->file[0].modification = true;
920 
921 	op->ops = &afs_setattr_operation;
922 	ret = afs_do_sync_operation(op);
923 
924 out_unlock:
925 	up_write(&vnode->validate_lock);
926 	fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);
927 	_leave(" = %d", ret);
928 	return ret;
929 }
930