xref: /openbmc/linux/fs/afs/super.c (revision e657c18a) 
1 /* AFS superblock handling
2  *
3  * Copyright (c) 2002, 2007, 2018 Red Hat, Inc. All rights reserved.
4  *
5  * This software may be freely redistributed under the terms of the
6  * GNU General Public License.
7  *
8  * You should have received a copy of the GNU General Public License
9  * along with this program; if not, write to the Free Software
10  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
11  *
12  * Authors: David Howells <dhowells@redhat.com>
13  *          David Woodhouse <dwmw2@infradead.org>
14  *
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/mount.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/fs.h>
23 #include <linux/pagemap.h>
24 #include <linux/fs_parser.h>
25 #include <linux/statfs.h>
26 #include <linux/sched.h>
27 #include <linux/nsproxy.h>
28 #include <linux/magic.h>
29 #include <net/net_namespace.h>
30 #include "internal.h"
31 
32 static void afs_i_init_once(void *foo);
33 static void afs_kill_super(struct super_block *sb);
34 static struct inode *afs_alloc_inode(struct super_block *sb);
35 static void afs_destroy_inode(struct inode *inode);
36 static int afs_statfs(struct dentry *dentry, struct kstatfs *buf);
37 static int afs_show_devname(struct seq_file *m, struct dentry *root);
38 static int afs_show_options(struct seq_file *m, struct dentry *root);
39 static int afs_init_fs_context(struct fs_context *fc);
40 static const struct fs_parameter_description afs_fs_parameters;
41 
42 struct file_system_type afs_fs_type = {
43 	.owner			= THIS_MODULE,
44 	.name			= "afs",
45 	.init_fs_context	= afs_init_fs_context,
46 	.parameters		= &afs_fs_parameters,
47 	.kill_sb		= afs_kill_super,
48 	.fs_flags		= 0,
49 };
50 MODULE_ALIAS_FS("afs");
51 
52 int afs_net_id;
53 
54 static const struct super_operations afs_super_ops = {
55 	.statfs		= afs_statfs,
56 	.alloc_inode	= afs_alloc_inode,
57 	.drop_inode	= afs_drop_inode,
58 	.destroy_inode	= afs_destroy_inode,
59 	.evict_inode	= afs_evict_inode,
60 	.show_devname	= afs_show_devname,
61 	.show_options	= afs_show_options,
62 };
63 
64 static struct kmem_cache *afs_inode_cachep;
65 static atomic_t afs_count_active_inodes;
66 
67 enum afs_param {
68 	Opt_autocell,
69 	Opt_dyn,
70 	Opt_source,
71 };
72 
73 static const struct fs_parameter_spec afs_param_specs[] = {
74 	fsparam_flag  ("autocell",	Opt_autocell),
75 	fsparam_flag  ("dyn",		Opt_dyn),
76 	fsparam_string("source",	Opt_source),
77 	{}
78 };
79 
80 static const struct fs_parameter_description afs_fs_parameters = {
81 	.name		= "kAFS",
82 	.specs		= afs_param_specs,
83 };
84 
85 /*
86  * initialise the filesystem
87  */
88 int __init afs_fs_init(void)
89 {
90 	int ret;
91 
92 	_enter("");
93 
94 	/* create ourselves an inode cache */
95 	atomic_set(&afs_count_active_inodes, 0);
96 
97 	ret = -ENOMEM;
98 	afs_inode_cachep = kmem_cache_create("afs_inode_cache",
99 					     sizeof(struct afs_vnode),
100 					     0,
101 					     SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
102 					     afs_i_init_once);
103 	if (!afs_inode_cachep) {
104 		printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
105 		return ret;
106 	}
107 
108 	/* now export our filesystem to lesser mortals */
109 	ret = register_filesystem(&afs_fs_type);
110 	if (ret < 0) {
111 		kmem_cache_destroy(afs_inode_cachep);
112 		_leave(" = %d", ret);
113 		return ret;
114 	}
115 
116 	_leave(" = 0");
117 	return 0;
118 }
119 
120 /*
121  * clean up the filesystem
122  */
123 void afs_fs_exit(void)
124 {
125 	_enter("");
126 
127 	afs_mntpt_kill_timer();
128 	unregister_filesystem(&afs_fs_type);
129 
130 	if (atomic_read(&afs_count_active_inodes) != 0) {
131 		printk("kAFS: %d active inode objects still present\n",
132 		       atomic_read(&afs_count_active_inodes));
133 		BUG();
134 	}
135 
136 	/*
137 	 * Make sure all delayed rcu free inodes are flushed before we
138 	 * destroy cache.
139 	 */
140 	rcu_barrier();
141 	kmem_cache_destroy(afs_inode_cachep);
142 	_leave("");
143 }
144 
145 /*
146  * Display the mount device name in /proc/mounts.
147  */
148 static int afs_show_devname(struct seq_file *m, struct dentry *root)
149 {
150 	struct afs_super_info *as = AFS_FS_S(root->d_sb);
151 	struct afs_volume *volume = as->volume;
152 	struct afs_cell *cell = as->cell;
153 	const char *suf = "";
154 	char pref = '%';
155 
156 	if (as->dyn_root) {
157 		seq_puts(m, "none");
158 		return 0;
159 	}
160 
161 	switch (volume->type) {
162 	case AFSVL_RWVOL:
163 		break;
164 	case AFSVL_ROVOL:
165 		pref = '#';
166 		if (volume->type_force)
167 			suf = ".readonly";
168 		break;
169 	case AFSVL_BACKVOL:
170 		pref = '#';
171 		suf = ".backup";
172 		break;
173 	}
174 
175 	seq_printf(m, "%c%s:%s%s", pref, cell->name, volume->name, suf);
176 	return 0;
177 }
178 
179 /*
180  * Display the mount options in /proc/mounts.
181  */
182 static int afs_show_options(struct seq_file *m, struct dentry *root)
183 {
184 	struct afs_super_info *as = AFS_FS_S(root->d_sb);
185 
186 	if (as->dyn_root)
187 		seq_puts(m, ",dyn");
188 	if (test_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(d_inode(root))->flags))
189 		seq_puts(m, ",autocell");
190 	return 0;
191 }
192 
193 /*
194  * Parse the source name to get cell name, volume name, volume type and R/W
195  * selector.
196  *
197  * This can be one of the following:
198  *	"%[cell:]volume[.]"		R/W volume
199  *	"#[cell:]volume[.]"		R/O or R/W volume (R/O parent),
200  *					 or R/W (R/W parent) volume
201  *	"%[cell:]volume.readonly"	R/O volume
202  *	"#[cell:]volume.readonly"	R/O volume
203  *	"%[cell:]volume.backup"		Backup volume
204  *	"#[cell:]volume.backup"		Backup volume
205  */
206 static int afs_parse_source(struct fs_context *fc, struct fs_parameter *param)
207 {
208 	struct afs_fs_context *ctx = fc->fs_private;
209 	struct afs_cell *cell;
210 	const char *cellname, *suffix, *name = param->string;
211 	int cellnamesz;
212 
213 	_enter(",%s", name);
214 
215 	if (!name) {
216 		printk(KERN_ERR "kAFS: no volume name specified\n");
217 		return -EINVAL;
218 	}
219 
220 	if ((name[0] != '%' && name[0] != '#') || !name[1]) {
221 		/* To use dynroot, we don't want to have to provide a source */
222 		if (strcmp(name, "none") == 0) {
223 			ctx->no_cell = true;
224 			return 0;
225 		}
226 		printk(KERN_ERR "kAFS: unparsable volume name\n");
227 		return -EINVAL;
228 	}
229 
230 	/* determine the type of volume we're looking for */
231 	if (name[0] == '%') {
232 		ctx->type = AFSVL_RWVOL;
233 		ctx->force = true;
234 	}
235 	name++;
236 
237 	/* split the cell name out if there is one */
238 	ctx->volname = strchr(name, ':');
239 	if (ctx->volname) {
240 		cellname = name;
241 		cellnamesz = ctx->volname - name;
242 		ctx->volname++;
243 	} else {
244 		ctx->volname = name;
245 		cellname = NULL;
246 		cellnamesz = 0;
247 	}
248 
249 	/* the volume type is further affected by a possible suffix */
250 	suffix = strrchr(ctx->volname, '.');
251 	if (suffix) {
252 		if (strcmp(suffix, ".readonly") == 0) {
253 			ctx->type = AFSVL_ROVOL;
254 			ctx->force = true;
255 		} else if (strcmp(suffix, ".backup") == 0) {
256 			ctx->type = AFSVL_BACKVOL;
257 			ctx->force = true;
258 		} else if (suffix[1] == 0) {
259 		} else {
260 			suffix = NULL;
261 		}
262 	}
263 
264 	ctx->volnamesz = suffix ?
265 		suffix - ctx->volname : strlen(ctx->volname);
266 
267 	_debug("cell %*.*s [%p]",
268 	       cellnamesz, cellnamesz, cellname ?: "", ctx->cell);
269 
270 	/* lookup the cell record */
271 	if (cellname) {
272 		cell = afs_lookup_cell(ctx->net, cellname, cellnamesz,
273 				       NULL, false);
274 		if (IS_ERR(cell)) {
275 			pr_err("kAFS: unable to lookup cell '%*.*s'\n",
276 			       cellnamesz, cellnamesz, cellname ?: "");
277 			return PTR_ERR(cell);
278 		}
279 		afs_put_cell(ctx->net, ctx->cell);
280 		ctx->cell = cell;
281 	}
282 
283 	_debug("CELL:%s [%p] VOLUME:%*.*s SUFFIX:%s TYPE:%d%s",
284 	       ctx->cell->name, ctx->cell,
285 	       ctx->volnamesz, ctx->volnamesz, ctx->volname,
286 	       suffix ?: "-", ctx->type, ctx->force ? " FORCE" : "");
287 
288 	fc->source = param->string;
289 	param->string = NULL;
290 	return 0;
291 }
292 
293 /*
294  * Parse a single mount parameter.
295  */
296 static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
297 {
298 	struct fs_parse_result result;
299 	struct afs_fs_context *ctx = fc->fs_private;
300 	int opt;
301 
302 	opt = fs_parse(fc, &afs_fs_parameters, param, &result);
303 	if (opt < 0)
304 		return opt;
305 
306 	switch (opt) {
307 	case Opt_source:
308 		return afs_parse_source(fc, param);
309 
310 	case Opt_autocell:
311 		ctx->autocell = true;
312 		break;
313 
314 	case Opt_dyn:
315 		ctx->dyn_root = true;
316 		break;
317 
318 	default:
319 		return -EINVAL;
320 	}
321 
322 	_leave(" = 0");
323 	return 0;
324 }
325 
326 /*
327  * Validate the options, get the cell key and look up the volume.
328  */
329 static int afs_validate_fc(struct fs_context *fc)
330 {
331 	struct afs_fs_context *ctx = fc->fs_private;
332 	struct afs_volume *volume;
333 	struct key *key;
334 
335 	if (!ctx->dyn_root) {
336 		if (ctx->no_cell) {
337 			pr_warn("kAFS: Can only specify source 'none' with -o dyn\n");
338 			return -EINVAL;
339 		}
340 
341 		if (!ctx->cell) {
342 			pr_warn("kAFS: No cell specified\n");
343 			return -EDESTADDRREQ;
344 		}
345 
346 		/* We try to do the mount securely. */
347 		key = afs_request_key(ctx->cell);
348 		if (IS_ERR(key))
349 			return PTR_ERR(key);
350 
351 		ctx->key = key;
352 
353 		if (ctx->volume) {
354 			afs_put_volume(ctx->cell, ctx->volume);
355 			ctx->volume = NULL;
356 		}
357 
358 		volume = afs_create_volume(ctx);
359 		if (IS_ERR(volume))
360 			return PTR_ERR(volume);
361 
362 		ctx->volume = volume;
363 	}
364 
365 	return 0;
366 }
367 
368 /*
369  * check a superblock to see if it's the one we're looking for
370  */
371 static int afs_test_super(struct super_block *sb, struct fs_context *fc)
372 {
373 	struct afs_fs_context *ctx = fc->fs_private;
374 	struct afs_super_info *as = AFS_FS_S(sb);
375 
376 	return (as->net_ns == fc->net_ns &&
377 		as->volume &&
378 		as->volume->vid == ctx->volume->vid &&
379 		!as->dyn_root);
380 }
381 
382 static int afs_dynroot_test_super(struct super_block *sb, struct fs_context *fc)
383 {
384 	struct afs_super_info *as = AFS_FS_S(sb);
385 
386 	return (as->net_ns == fc->net_ns &&
387 		as->dyn_root);
388 }
389 
390 static int afs_set_super(struct super_block *sb, struct fs_context *fc)
391 {
392 	return set_anon_super(sb, NULL);
393 }
394 
395 /*
396  * fill in the superblock
397  */
398 static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
399 {
400 	struct afs_super_info *as = AFS_FS_S(sb);
401 	struct afs_fid fid;
402 	struct inode *inode = NULL;
403 	int ret;
404 
405 	_enter("");
406 
407 	/* fill in the superblock */
408 	sb->s_blocksize		= PAGE_SIZE;
409 	sb->s_blocksize_bits	= PAGE_SHIFT;
410 	sb->s_magic		= AFS_FS_MAGIC;
411 	sb->s_op		= &afs_super_ops;
412 	if (!as->dyn_root)
413 		sb->s_xattr	= afs_xattr_handlers;
414 	ret = super_setup_bdi(sb);
415 	if (ret)
416 		return ret;
417 	sb->s_bdi->ra_pages	= VM_READAHEAD_PAGES;
418 
419 	/* allocate the root inode and dentry */
420 	if (as->dyn_root) {
421 		inode = afs_iget_pseudo_dir(sb, true);
422 		sb->s_flags	|= SB_RDONLY;
423 	} else {
424 		sprintf(sb->s_id, "%llu", as->volume->vid);
425 		afs_activate_volume(as->volume);
426 		fid.vid		= as->volume->vid;
427 		fid.vnode	= 1;
428 		fid.vnode_hi	= 0;
429 		fid.unique	= 1;
430 		inode = afs_iget(sb, ctx->key, &fid, NULL, NULL, NULL);
431 	}
432 
433 	if (IS_ERR(inode))
434 		return PTR_ERR(inode);
435 
436 	if (ctx->autocell || as->dyn_root)
437 		set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
438 
439 	ret = -ENOMEM;
440 	sb->s_root = d_make_root(inode);
441 	if (!sb->s_root)
442 		goto error;
443 
444 	if (as->dyn_root) {
445 		sb->s_d_op = &afs_dynroot_dentry_operations;
446 		ret = afs_dynroot_populate(sb);
447 		if (ret < 0)
448 			goto error;
449 	} else {
450 		sb->s_d_op = &afs_fs_dentry_operations;
451 	}
452 
453 	_leave(" = 0");
454 	return 0;
455 
456 error:
457 	_leave(" = %d", ret);
458 	return ret;
459 }
460 
461 static struct afs_super_info *afs_alloc_sbi(struct fs_context *fc)
462 {
463 	struct afs_fs_context *ctx = fc->fs_private;
464 	struct afs_super_info *as;
465 
466 	as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
467 	if (as) {
468 		as->net_ns = get_net(fc->net_ns);
469 		if (ctx->dyn_root) {
470 			as->dyn_root = true;
471 		} else {
472 			as->cell = afs_get_cell(ctx->cell);
473 			as->volume = __afs_get_volume(ctx->volume);
474 		}
475 	}
476 	return as;
477 }
478 
479 static void afs_destroy_sbi(struct afs_super_info *as)
480 {
481 	if (as) {
482 		afs_put_volume(as->cell, as->volume);
483 		afs_put_cell(afs_net(as->net_ns), as->cell);
484 		put_net(as->net_ns);
485 		kfree(as);
486 	}
487 }
488 
489 static void afs_kill_super(struct super_block *sb)
490 {
491 	struct afs_super_info *as = AFS_FS_S(sb);
492 	struct afs_net *net = afs_net(as->net_ns);
493 
494 	if (as->dyn_root)
495 		afs_dynroot_depopulate(sb);
496 
497 	/* Clear the callback interests (which will do ilookup5) before
498 	 * deactivating the superblock.
499 	 */
500 	if (as->volume)
501 		afs_clear_callback_interests(net, as->volume->servers);
502 	kill_anon_super(sb);
503 	if (as->volume)
504 		afs_deactivate_volume(as->volume);
505 	afs_destroy_sbi(as);
506 }
507 
508 /*
509  * Get an AFS superblock and root directory.
510  */
511 static int afs_get_tree(struct fs_context *fc)
512 {
513 	struct afs_fs_context *ctx = fc->fs_private;
514 	struct super_block *sb;
515 	struct afs_super_info *as;
516 	int ret;
517 
518 	ret = afs_validate_fc(fc);
519 	if (ret)
520 		goto error;
521 
522 	_enter("");
523 
524 	/* allocate a superblock info record */
525 	ret = -ENOMEM;
526 	as = afs_alloc_sbi(fc);
527 	if (!as)
528 		goto error;
529 	fc->s_fs_info = as;
530 
531 	/* allocate a deviceless superblock */
532 	sb = sget_fc(fc,
533 		     as->dyn_root ? afs_dynroot_test_super : afs_test_super,
534 		     afs_set_super);
535 	if (IS_ERR(sb)) {
536 		ret = PTR_ERR(sb);
537 		goto error;
538 	}
539 
540 	if (!sb->s_root) {
541 		/* initial superblock/root creation */
542 		_debug("create");
543 		ret = afs_fill_super(sb, ctx);
544 		if (ret < 0)
545 			goto error_sb;
546 		sb->s_flags |= SB_ACTIVE;
547 	} else {
548 		_debug("reuse");
549 		ASSERTCMP(sb->s_flags, &, SB_ACTIVE);
550 	}
551 
552 	fc->root = dget(sb->s_root);
553 	_leave(" = 0 [%p]", sb);
554 	return 0;
555 
556 error_sb:
557 	deactivate_locked_super(sb);
558 error:
559 	_leave(" = %d", ret);
560 	return ret;
561 }
562 
563 static void afs_free_fc(struct fs_context *fc)
564 {
565 	struct afs_fs_context *ctx = fc->fs_private;
566 
567 	afs_destroy_sbi(fc->s_fs_info);
568 	afs_put_volume(ctx->cell, ctx->volume);
569 	afs_put_cell(ctx->net, ctx->cell);
570 	key_put(ctx->key);
571 	kfree(ctx);
572 }
573 
574 static const struct fs_context_operations afs_context_ops = {
575 	.free		= afs_free_fc,
576 	.parse_param	= afs_parse_param,
577 	.get_tree	= afs_get_tree,
578 };
579 
580 /*
581  * Set up the filesystem mount context.
582  */
583 static int afs_init_fs_context(struct fs_context *fc)
584 {
585 	struct afs_fs_context *ctx;
586 	struct afs_cell *cell;
587 
588 	ctx = kzalloc(sizeof(struct afs_fs_context), GFP_KERNEL);
589 	if (!ctx)
590 		return -ENOMEM;
591 
592 	ctx->type = AFSVL_ROVOL;
593 	ctx->net = afs_net(fc->net_ns);
594 
595 	/* Default to the workstation cell. */
596 	rcu_read_lock();
597 	cell = afs_lookup_cell_rcu(ctx->net, NULL, 0);
598 	rcu_read_unlock();
599 	if (IS_ERR(cell))
600 		cell = NULL;
601 	ctx->cell = cell;
602 
603 	fc->fs_private = ctx;
604 	fc->ops = &afs_context_ops;
605 	return 0;
606 }
607 
608 /*
609  * Initialise an inode cache slab element prior to any use.  Note that
610  * afs_alloc_inode() *must* reset anything that could incorrectly leak from one
611  * inode to another.
612  */
613 static void afs_i_init_once(void *_vnode)
614 {
615 	struct afs_vnode *vnode = _vnode;
616 
617 	memset(vnode, 0, sizeof(*vnode));
618 	inode_init_once(&vnode->vfs_inode);
619 	mutex_init(&vnode->io_lock);
620 	init_rwsem(&vnode->validate_lock);
621 	spin_lock_init(&vnode->wb_lock);
622 	spin_lock_init(&vnode->lock);
623 	INIT_LIST_HEAD(&vnode->wb_keys);
624 	INIT_LIST_HEAD(&vnode->pending_locks);
625 	INIT_LIST_HEAD(&vnode->granted_locks);
626 	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);
627 	seqlock_init(&vnode->cb_lock);
628 }
629 
630 /*
631  * allocate an AFS inode struct from our slab cache
632  */
633 static struct inode *afs_alloc_inode(struct super_block *sb)
634 {
635 	struct afs_vnode *vnode;
636 
637 	vnode = kmem_cache_alloc(afs_inode_cachep, GFP_KERNEL);
638 	if (!vnode)
639 		return NULL;
640 
641 	atomic_inc(&afs_count_active_inodes);
642 
643 	/* Reset anything that shouldn't leak from one inode to the next. */
644 	memset(&vnode->fid, 0, sizeof(vnode->fid));
645 	memset(&vnode->status, 0, sizeof(vnode->status));
646 
647 	vnode->volume		= NULL;
648 	vnode->lock_key		= NULL;
649 	vnode->permit_cache	= NULL;
650 	vnode->cb_interest	= NULL;
651 #ifdef CONFIG_AFS_FSCACHE
652 	vnode->cache		= NULL;
653 #endif
654 
655 	vnode->flags		= 1 << AFS_VNODE_UNSET;
656 	vnode->cb_type		= 0;
657 	vnode->lock_state	= AFS_VNODE_LOCK_NONE;
658 
659 	_leave(" = %p", &vnode->vfs_inode);
660 	return &vnode->vfs_inode;
661 }
662 
663 static void afs_i_callback(struct rcu_head *head)
664 {
665 	struct inode *inode = container_of(head, struct inode, i_rcu);
666 	struct afs_vnode *vnode = AFS_FS_I(inode);
667 	kmem_cache_free(afs_inode_cachep, vnode);
668 }
669 
670 /*
671  * destroy an AFS inode struct
672  */
673 static void afs_destroy_inode(struct inode *inode)
674 {
675 	struct afs_vnode *vnode = AFS_FS_I(inode);
676 
677 	_enter("%p{%llx:%llu}", inode, vnode->fid.vid, vnode->fid.vnode);
678 
679 	_debug("DESTROY INODE %p", inode);
680 
681 	ASSERTCMP(vnode->cb_interest, ==, NULL);
682 
683 	call_rcu(&inode->i_rcu, afs_i_callback);
684 	atomic_dec(&afs_count_active_inodes);
685 }
686 
687 /*
688  * return information about an AFS volume
689  */
690 static int afs_statfs(struct dentry *dentry, struct kstatfs *buf)
691 {
692 	struct afs_super_info *as = AFS_FS_S(dentry->d_sb);
693 	struct afs_fs_cursor fc;
694 	struct afs_volume_status vs;
695 	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
696 	struct key *key;
697 	int ret;
698 
699 	buf->f_type	= dentry->d_sb->s_magic;
700 	buf->f_bsize	= AFS_BLOCK_SIZE;
701 	buf->f_namelen	= AFSNAMEMAX - 1;
702 
703 	if (as->dyn_root) {
704 		buf->f_blocks	= 1;
705 		buf->f_bavail	= 0;
706 		buf->f_bfree	= 0;
707 		return 0;
708 	}
709 
710 	key = afs_request_key(vnode->volume->cell);
711 	if (IS_ERR(key))
712 		return PTR_ERR(key);
713 
714 	ret = -ERESTARTSYS;
715 	if (afs_begin_vnode_operation(&fc, vnode, key)) {
716 		fc.flags |= AFS_FS_CURSOR_NO_VSLEEP;
717 		while (afs_select_fileserver(&fc)) {
718 			fc.cb_break = afs_calc_vnode_cb_break(vnode);
719 			afs_fs_get_volume_status(&fc, &vs);
720 		}
721 
722 		afs_check_for_remote_deletion(&fc, fc.vnode);
723 		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
724 		ret = afs_end_vnode_operation(&fc);
725 	}
726 
727 	key_put(key);
728 
729 	if (ret == 0) {
730 		if (vs.max_quota == 0)
731 			buf->f_blocks = vs.part_max_blocks;
732 		else
733 			buf->f_blocks = vs.max_quota;
734 		buf->f_bavail = buf->f_bfree = buf->f_blocks - vs.blocks_in_use;
735 	}
736 
737 	return ret;
738 }
739