Linux Audio

Check our new training course

Yocto / OpenEmbedded training

Feb 10-13, 2025
Register
Loading...
  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		inode_nohighmem(inode);
 60		break;
 61	default:
 62		printk("kAFS: AFS vnode with undefined type\n");
 63		return -EBADMSG;
 
 64	}
 65
 66#ifdef CONFIG_AFS_FSCACHE
 67	if (vnode->status.size != inode->i_size)
 68		fscache_attr_changed(vnode->cache);
 69#endif
 70
 71	set_nlink(inode, vnode->status.nlink);
 72	inode->i_uid		= vnode->status.owner;
 73	inode->i_gid		= GLOBAL_ROOT_GID;
 74	inode->i_size		= vnode->status.size;
 75	inode->i_ctime.tv_sec	= vnode->status.mtime_server;
 76	inode->i_ctime.tv_nsec	= 0;
 77	inode->i_atime		= inode->i_mtime = inode->i_ctime;
 78	inode->i_blocks		= 0;
 79	inode->i_generation	= vnode->fid.unique;
 80	inode->i_version	= vnode->status.data_version;
 81	inode->i_mapping->a_ops	= &afs_fs_aops;
 82
 83	/* check to see whether a symbolic link is really a mountpoint */
 84	if (vnode->status.type == AFS_FTYPE_SYMLINK) {
 85		afs_mntpt_check_symlink(vnode, key);
 86
 87		if (test_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags)) {
 88			inode->i_mode	= S_IFDIR | vnode->status.mode;
 89			inode->i_op	= &afs_mntpt_inode_operations;
 90			inode->i_fop	= &afs_mntpt_file_operations;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 91		}
 
 
 
 
 92	}
 93
 94	return 0;
 
 95}
 96
 97/*
 98 * iget5() comparator
 99 */
100static int afs_iget5_test(struct inode *inode, void *opaque)
101{
102	struct afs_iget_data *data = opaque;
103
104	return inode->i_ino == data->fid.vnode &&
105		inode->i_generation == data->fid.unique;
106}
107
108/*
109 * iget5() comparator for inode created by autocell operations
110 *
111 * These pseudo inodes don't match anything.
112 */
113static int afs_iget5_autocell_test(struct inode *inode, void *opaque)
114{
115	return 0;
116}
117
118/*
119 * iget5() inode initialiser
120 */
121static int afs_iget5_set(struct inode *inode, void *opaque)
122{
123	struct afs_iget_data *data = opaque;
124	struct afs_vnode *vnode = AFS_FS_I(inode);
125
126	inode->i_ino = data->fid.vnode;
127	inode->i_generation = data->fid.unique;
128	vnode->fid = data->fid;
129	vnode->volume = data->volume;
130
131	return 0;
132}
133
134/*
135 * inode retrieval for autocell
 
136 */
137struct inode *afs_iget_autocell(struct inode *dir, const char *dev_name,
138				int namesz, struct key *key)
139{
140	struct afs_iget_data data;
141	struct afs_super_info *as;
142	struct afs_vnode *vnode;
143	struct super_block *sb;
144	struct inode *inode;
145	static atomic_t afs_autocell_ino;
146
147	_enter("{%x:%u},%*.*s,",
148	       AFS_FS_I(dir)->fid.vid, AFS_FS_I(dir)->fid.vnode,
149	       namesz, namesz, dev_name ?: "");
150
151	sb = dir->i_sb;
152	as = sb->s_fs_info;
153	data.volume = as->volume;
154	data.fid.vid = as->volume->vid;
155	data.fid.unique = 0;
156	data.fid.vnode = 0;
 
 
 
 
 
 
 
157
158	inode = iget5_locked(sb, atomic_inc_return(&afs_autocell_ino),
159			     afs_iget5_autocell_test, afs_iget5_set,
160			     &data);
161	if (!inode) {
162		_leave(" = -ENOMEM");
163		return ERR_PTR(-ENOMEM);
164	}
165
166	_debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
167	       inode, inode->i_ino, data.fid.vid, data.fid.vnode,
168	       data.fid.unique);
169
170	vnode = AFS_FS_I(inode);
171
172	/* there shouldn't be an existing inode */
173	BUG_ON(!(inode->i_state & I_NEW));
174
175	inode->i_size		= 0;
176	inode->i_mode		= S_IFDIR | S_IRUGO | S_IXUGO;
177	inode->i_op		= &afs_autocell_inode_operations;
 
 
 
 
 
178	set_nlink(inode, 2);
179	inode->i_uid		= GLOBAL_ROOT_UID;
180	inode->i_gid		= GLOBAL_ROOT_GID;
181	inode->i_ctime.tv_sec	= get_seconds();
182	inode->i_ctime.tv_nsec	= 0;
183	inode->i_atime		= inode->i_mtime = inode->i_ctime;
184	inode->i_blocks		= 0;
185	inode->i_version	= 0;
186	inode->i_generation	= 0;
187
188	set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
189	set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
190	inode->i_flags |= S_AUTOMOUNT | S_NOATIME;
 
 
 
 
191	unlock_new_inode(inode);
192	_leave(" = %p", inode);
193	return inode;
194}
195
196/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
197 * inode retrieval
198 */
199struct inode *afs_iget(struct super_block *sb, struct key *key,
200		       struct afs_fid *fid, struct afs_file_status *status,
201		       struct afs_callback *cb)
202{
203	struct afs_iget_data data = { .fid = *fid };
204	struct afs_super_info *as;
205	struct afs_vnode *vnode;
206	struct inode *inode;
207	int ret;
208
209	_enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
210
211	as = sb->s_fs_info;
212	data.volume = as->volume;
213
214	inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
215			     &data);
216	if (!inode) {
217		_leave(" = -ENOMEM");
218		return ERR_PTR(-ENOMEM);
219	}
220
221	_debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
222	       inode, fid->vid, fid->vnode, fid->unique);
223
224	vnode = AFS_FS_I(inode);
225
226	/* deal with an existing inode */
227	if (!(inode->i_state & I_NEW)) {
228		_leave(" = %p", inode);
229		return inode;
230	}
231
232	if (!status) {
233		/* it's a remotely extant inode */
234		set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
235		ret = afs_vnode_fetch_status(vnode, NULL, key);
236		if (ret < 0)
237			goto bad_inode;
238	} else {
239		/* it's an inode we just created */
240		memcpy(&vnode->status, status, sizeof(vnode->status));
241
242		if (!cb) {
243			/* it's a symlink we just created (the fileserver
244			 * didn't give us a callback) */
245			vnode->cb_version = 0;
246			vnode->cb_expiry = 0;
247			vnode->cb_type = 0;
248			vnode->cb_expires = get_seconds();
249		} else {
250			vnode->cb_version = cb->version;
251			vnode->cb_expiry = cb->expiry;
252			vnode->cb_type = cb->type;
253			vnode->cb_expires = vnode->cb_expiry + get_seconds();
 
 
254		}
255	}
256
257	/* set up caching before mapping the status, as map-status reads the
258	 * first page of symlinks to see if they're really mountpoints */
259	inode->i_size = vnode->status.size;
260#ifdef CONFIG_AFS_FSCACHE
261	vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
262					      &afs_vnode_cache_index_def,
263					      vnode, true);
264#endif
265
266	ret = afs_inode_map_status(vnode, key);
267	if (ret < 0)
268		goto bad_inode;
269
 
 
270	/* success */
271	clear_bit(AFS_VNODE_UNSET, &vnode->flags);
272	inode->i_flags |= S_NOATIME;
273	unlock_new_inode(inode);
274	_leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
275	return inode;
276
277	/* failure */
278bad_inode:
279#ifdef CONFIG_AFS_FSCACHE
280	fscache_relinquish_cookie(vnode->cache, 0);
281	vnode->cache = NULL;
282#endif
283	iget_failed(inode);
284	_leave(" = %d [bad]", ret);
285	return ERR_PTR(ret);
286}
287
288/*
289 * mark the data attached to an inode as obsolete due to a write on the server
290 * - might also want to ditch all the outstanding writes and dirty pages
291 */
292void afs_zap_data(struct afs_vnode *vnode)
293{
294	_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
295
 
 
 
 
296	/* nuke all the non-dirty pages that aren't locked, mapped or being
297	 * written back in a regular file and completely discard the pages in a
298	 * directory or symlink */
299	if (S_ISREG(vnode->vfs_inode.i_mode))
300		invalidate_remote_inode(&vnode->vfs_inode);
301	else
302		invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
303}
304
305/*
306 * validate a vnode/inode
307 * - there are several things we need to check
308 *   - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
309 *     symlink)
310 *   - parent dir metadata changed (security changes)
311 *   - dentry data changed (write, truncate)
312 *   - dentry metadata changed (security changes)
313 */
314int afs_validate(struct afs_vnode *vnode, struct key *key)
315{
 
 
316	int ret;
317
318	_enter("{v={%x:%u} fl=%lx},%x",
319	       vnode->fid.vid, vnode->fid.vnode, vnode->flags,
320	       key_serial(key));
321
322	if (vnode->cb_promised &&
323	    !test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
324	    !test_bit(AFS_VNODE_MODIFIED, &vnode->flags) &&
325	    !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
326		if (vnode->cb_expires < get_seconds() + 10) {
327			_debug("callback expired");
328			set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
329		} else {
330			goto valid;
 
 
 
 
 
 
 
 
 
 
331		}
 
 
332	}
333
 
 
334	if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
 
 
 
335		goto valid;
336
337	mutex_lock(&vnode->validate_lock);
338
339	/* if the promise has expired, we need to check the server again to get
340	 * a new promise - note that if the (parent) directory's metadata was
341	 * changed then the security may be different and we may no longer have
342	 * access */
343	if (!vnode->cb_promised ||
344	    test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) {
345		_debug("not promised");
346		ret = afs_vnode_fetch_status(vnode, NULL, key);
347		if (ret < 0)
 
 
 
 
348			goto error_unlock;
 
349		_debug("new promise [fl=%lx]", vnode->flags);
350	}
351
352	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
353		_debug("file already deleted");
354		ret = -ESTALE;
355		goto error_unlock;
356	}
357
358	/* if the vnode's data version number changed then its contents are
359	 * different */
360	if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
361		afs_zap_data(vnode);
362
363	clear_bit(AFS_VNODE_MODIFIED, &vnode->flags);
364	mutex_unlock(&vnode->validate_lock);
365valid:
366	_leave(" = 0");
367	return 0;
368
369error_unlock:
370	mutex_unlock(&vnode->validate_lock);
371	_leave(" = %d", ret);
372	return ret;
373}
374
375/*
376 * read the attributes of an inode
377 */
378int afs_getattr(struct vfsmount *mnt, struct dentry *dentry,
379		      struct kstat *stat)
380{
381	struct inode *inode;
382
383	inode = d_inode(dentry);
384
385	_enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
386
387	generic_fillattr(inode, stat);
 
 
 
 
 
388	return 0;
389}
390
391/*
392 * discard an AFS inode
393 */
394int afs_drop_inode(struct inode *inode)
395{
396	_enter("");
397
398	if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
399		return generic_delete_inode(inode);
400	else
401		return generic_drop_inode(inode);
402}
403
404/*
405 * clear an AFS inode
406 */
407void afs_evict_inode(struct inode *inode)
408{
409	struct afs_permits *permits;
410	struct afs_vnode *vnode;
411
412	vnode = AFS_FS_I(inode);
413
414	_enter("{%x:%u.%d} v=%u x=%u t=%u }",
415	       vnode->fid.vid,
416	       vnode->fid.vnode,
417	       vnode->fid.unique,
418	       vnode->cb_version,
419	       vnode->cb_expiry,
420	       vnode->cb_type);
421
422	_debug("CLEAR INODE %p", inode);
423
424	ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
425
426	truncate_inode_pages_final(&inode->i_data);
427	clear_inode(inode);
428
429	afs_give_up_callback(vnode);
430
431	if (vnode->server) {
432		spin_lock(&vnode->server->fs_lock);
433		rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes);
434		spin_unlock(&vnode->server->fs_lock);
435		afs_put_server(vnode->server);
436		vnode->server = NULL;
437	}
438
439	ASSERT(list_empty(&vnode->writebacks));
440	ASSERT(!vnode->cb_promised);
 
 
 
 
441
442#ifdef CONFIG_AFS_FSCACHE
443	fscache_relinquish_cookie(vnode->cache, 0);
444	vnode->cache = NULL;
445#endif
446
447	mutex_lock(&vnode->permits_lock);
448	permits = vnode->permits;
449	rcu_assign_pointer(vnode->permits, NULL);
450	mutex_unlock(&vnode->permits_lock);
451	if (permits)
452		call_rcu(&permits->rcu, afs_zap_permits);
453
 
454	_leave("");
455}
456
457/*
458 * set the attributes of an inode
459 */
460int afs_setattr(struct dentry *dentry, struct iattr *attr)
461{
 
462	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
463	struct key *key;
464	int ret;
465
466	_enter("{%x:%u},{n=%pd},%x",
467	       vnode->fid.vid, vnode->fid.vnode, dentry,
468	       attr->ia_valid);
469
470	if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
471				ATTR_MTIME))) {
472		_leave(" = 0 [unsupported]");
473		return 0;
474	}
475
476	/* flush any dirty data outstanding on a regular file */
477	if (S_ISREG(vnode->vfs_inode.i_mode)) {
478		filemap_write_and_wait(vnode->vfs_inode.i_mapping);
479		afs_writeback_all(vnode);
480	}
481
482	if (attr->ia_valid & ATTR_FILE) {
483		key = attr->ia_file->private_data;
484	} else {
485		key = afs_request_key(vnode->volume->cell);
486		if (IS_ERR(key)) {
487			ret = PTR_ERR(key);
488			goto error;
489		}
490	}
491
492	ret = afs_vnode_setattr(vnode, key, attr);
 
 
 
 
 
 
 
 
 
 
 
493	if (!(attr->ia_valid & ATTR_FILE))
494		key_put(key);
495
496error:
497	_leave(" = %d", ret);
498	return ret;
499}
  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
 27static const struct inode_operations afs_symlink_inode_operations = {
 28	.get_link	= page_get_link,
 29	.listxattr	= afs_listxattr,
 30};
 31
 32/*
 33 * Initialise an inode from the vnode status.
 34 */
 35static int afs_inode_init_from_status(struct afs_vnode *vnode, struct key *key)
 36{
 37	struct inode *inode = AFS_VNODE_TO_I(vnode);
 38
 39	_debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
 40	       vnode->status.type,
 41	       vnode->status.nlink,
 42	       (unsigned long long) vnode->status.size,
 43	       vnode->status.data_version,
 44	       vnode->status.mode);
 45
 46	read_seqlock_excl(&vnode->cb_lock);
 47
 48	afs_update_inode_from_status(vnode, &vnode->status, NULL,
 49				     AFS_VNODE_NOT_YET_SET);
 50
 51	switch (vnode->status.type) {
 52	case AFS_FTYPE_FILE:
 53		inode->i_mode	= S_IFREG | vnode->status.mode;
 54		inode->i_op	= &afs_file_inode_operations;
 55		inode->i_fop	= &afs_file_operations;
 56		inode->i_mapping->a_ops	= &afs_fs_aops;
 57		break;
 58	case AFS_FTYPE_DIR:
 59		inode->i_mode	= S_IFDIR | vnode->status.mode;
 60		inode->i_op	= &afs_dir_inode_operations;
 61		inode->i_fop	= &afs_dir_file_operations;
 62		inode->i_mapping->a_ops	= &afs_dir_aops;
 63		break;
 64	case AFS_FTYPE_SYMLINK:
 65		/* Symlinks with a mode of 0644 are actually mountpoints. */
 66		if ((vnode->status.mode & 0777) == 0644) {
 67			inode->i_flags |= S_AUTOMOUNT;
 68
 69			set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
 70
 71			inode->i_mode	= S_IFDIR | 0555;
 72			inode->i_op	= &afs_mntpt_inode_operations;
 73			inode->i_fop	= &afs_mntpt_file_operations;
 74			inode->i_mapping->a_ops	= &afs_fs_aops;
 75		} else {
 76			inode->i_mode	= S_IFLNK | vnode->status.mode;
 77			inode->i_op	= &afs_symlink_inode_operations;
 78			inode->i_mapping->a_ops	= &afs_fs_aops;
 79		}
 80		inode_nohighmem(inode);
 81		break;
 82	default:
 83		printk("kAFS: AFS vnode with undefined type\n");
 84		read_sequnlock_excl(&vnode->cb_lock);
 85		return afs_protocol_error(NULL, -EBADMSG);
 86	}
 87
 
 
 
 
 
 
 
 
 
 
 
 
 88	inode->i_blocks		= 0;
 89	vnode->invalid_before	= vnode->status.data_version;
 
 
 
 
 
 
 90
 91	read_sequnlock_excl(&vnode->cb_lock);
 92	return 0;
 93}
 94
 95/*
 96 * Fetch file status from the volume.
 97 */
 98int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool new_inode)
 99{
100	struct afs_fs_cursor fc;
101	int ret;
102
103	_enter("%s,{%x:%u.%u,S=%lx}",
104	       vnode->volume->name,
105	       vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique,
106	       vnode->flags);
107
108	ret = -ERESTARTSYS;
109	if (afs_begin_vnode_operation(&fc, vnode, key)) {
110		while (afs_select_fileserver(&fc)) {
111			fc.cb_break = afs_calc_vnode_cb_break(vnode);
112			afs_fs_fetch_file_status(&fc, NULL, new_inode);
113		}
114
115		afs_check_for_remote_deletion(&fc, fc.vnode);
116		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
117		ret = afs_end_vnode_operation(&fc);
118	}
119
120	_leave(" = %d", ret);
121	return ret;
122}
123
124/*
125 * iget5() comparator
126 */
127int afs_iget5_test(struct inode *inode, void *opaque)
128{
129	struct afs_iget_data *data = opaque;
130
131	return inode->i_ino == data->fid.vnode &&
132		inode->i_generation == data->fid.unique;
133}
134
135/*
136 * iget5() comparator for inode created by autocell operations
137 *
138 * These pseudo inodes don't match anything.
139 */
140static int afs_iget5_pseudo_dir_test(struct inode *inode, void *opaque)
141{
142	return 0;
143}
144
145/*
146 * iget5() inode initialiser
147 */
148static int afs_iget5_set(struct inode *inode, void *opaque)
149{
150	struct afs_iget_data *data = opaque;
151	struct afs_vnode *vnode = AFS_FS_I(inode);
152
153	inode->i_ino = data->fid.vnode;
154	inode->i_generation = data->fid.unique;
155	vnode->fid = data->fid;
156	vnode->volume = data->volume;
157
158	return 0;
159}
160
161/*
162 * Create an inode for a dynamic root directory or an autocell dynamic
163 * automount dir.
164 */
165struct inode *afs_iget_pseudo_dir(struct super_block *sb, bool root)
 
166{
167	struct afs_iget_data data;
168	struct afs_super_info *as;
169	struct afs_vnode *vnode;
 
170	struct inode *inode;
171	static atomic_t afs_autocell_ino;
172
173	_enter("");
 
 
174
 
175	as = sb->s_fs_info;
176	if (as->volume) {
177		data.volume = as->volume;
178		data.fid.vid = as->volume->vid;
179	}
180	if (root) {
181		data.fid.vnode = 1;
182		data.fid.unique = 1;
183	} else {
184		data.fid.vnode = atomic_inc_return(&afs_autocell_ino);
185		data.fid.unique = 0;
186	}
187
188	inode = iget5_locked(sb, data.fid.vnode,
189			     afs_iget5_pseudo_dir_test, afs_iget5_set,
190			     &data);
191	if (!inode) {
192		_leave(" = -ENOMEM");
193		return ERR_PTR(-ENOMEM);
194	}
195
196	_debug("GOT INODE %p { ino=%lu, vl=%x, vn=%x, u=%x }",
197	       inode, inode->i_ino, data.fid.vid, data.fid.vnode,
198	       data.fid.unique);
199
200	vnode = AFS_FS_I(inode);
201
202	/* there shouldn't be an existing inode */
203	BUG_ON(!(inode->i_state & I_NEW));
204
205	inode->i_size		= 0;
206	inode->i_mode		= S_IFDIR | S_IRUGO | S_IXUGO;
207	if (root) {
208		inode->i_op	= &afs_dynroot_inode_operations;
209		inode->i_fop	= &afs_dynroot_file_operations;
210	} else {
211		inode->i_op	= &afs_autocell_inode_operations;
212	}
213	set_nlink(inode, 2);
214	inode->i_uid		= GLOBAL_ROOT_UID;
215	inode->i_gid		= GLOBAL_ROOT_GID;
216	inode->i_ctime.tv_sec	= get_seconds();
217	inode->i_ctime.tv_nsec	= 0;
218	inode->i_atime		= inode->i_mtime = inode->i_ctime;
219	inode->i_blocks		= 0;
220	inode_set_iversion_raw(inode, 0);
221	inode->i_generation	= 0;
222
223	set_bit(AFS_VNODE_PSEUDODIR, &vnode->flags);
224	if (!root) {
225		set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
226		inode->i_flags |= S_AUTOMOUNT;
227	}
228
229	inode->i_flags |= S_NOATIME;
230	unlock_new_inode(inode);
231	_leave(" = %p", inode);
232	return inode;
233}
234
235/*
236 * Get a cache cookie for an inode.
237 */
238static void afs_get_inode_cache(struct afs_vnode *vnode)
239{
240#ifdef CONFIG_AFS_FSCACHE
241	struct {
242		u32 vnode_id;
243		u32 unique;
244		u32 vnode_id_ext[2];	/* Allow for a 96-bit key */
245	} __packed key;
246	struct afs_vnode_cache_aux aux;
247
248	if (vnode->status.type == AFS_FTYPE_DIR) {
249		vnode->cache = NULL;
250		return;
251	}
252
253	key.vnode_id		= vnode->fid.vnode;
254	key.unique		= vnode->fid.unique;
255	key.vnode_id_ext[0]	= 0;
256	key.vnode_id_ext[1]	= 0;
257	aux.data_version	= vnode->status.data_version;
258
259	vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
260					      &afs_vnode_cache_index_def,
261					      &key, sizeof(key),
262					      &aux, sizeof(aux),
263					      vnode, vnode->status.size, true);
264#endif
265}
266
267/*
268 * inode retrieval
269 */
270struct inode *afs_iget(struct super_block *sb, struct key *key,
271		       struct afs_fid *fid, struct afs_file_status *status,
272		       struct afs_callback *cb, struct afs_cb_interest *cbi)
273{
274	struct afs_iget_data data = { .fid = *fid };
275	struct afs_super_info *as;
276	struct afs_vnode *vnode;
277	struct inode *inode;
278	int ret;
279
280	_enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
281
282	as = sb->s_fs_info;
283	data.volume = as->volume;
284
285	inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
286			     &data);
287	if (!inode) {
288		_leave(" = -ENOMEM");
289		return ERR_PTR(-ENOMEM);
290	}
291
292	_debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
293	       inode, fid->vid, fid->vnode, fid->unique);
294
295	vnode = AFS_FS_I(inode);
296
297	/* deal with an existing inode */
298	if (!(inode->i_state & I_NEW)) {
299		_leave(" = %p", inode);
300		return inode;
301	}
302
303	if (!status) {
304		/* it's a remotely extant inode */
305		ret = afs_fetch_status(vnode, key, true);
 
306		if (ret < 0)
307			goto bad_inode;
308	} else {
309		/* it's an inode we just created */
310		memcpy(&vnode->status, status, sizeof(vnode->status));
311
312		if (!cb) {
313			/* it's a symlink we just created (the fileserver
314			 * didn't give us a callback) */
315			vnode->cb_version = 0;
 
316			vnode->cb_type = 0;
317			vnode->cb_expires_at = 0;
318		} else {
319			vnode->cb_version = cb->version;
 
320			vnode->cb_type = cb->type;
321			vnode->cb_expires_at = cb->expiry;
322			vnode->cb_interest = afs_get_cb_interest(cbi);
323			set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
324		}
 
325
326		vnode->cb_expires_at += ktime_get_real_seconds();
327	}
 
 
 
 
 
 
328
329	ret = afs_inode_init_from_status(vnode, key);
330	if (ret < 0)
331		goto bad_inode;
332
333	afs_get_inode_cache(vnode);
334
335	/* success */
336	clear_bit(AFS_VNODE_UNSET, &vnode->flags);
337	inode->i_flags |= S_NOATIME;
338	unlock_new_inode(inode);
339	_leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
340	return inode;
341
342	/* failure */
343bad_inode:
 
 
 
 
344	iget_failed(inode);
345	_leave(" = %d [bad]", ret);
346	return ERR_PTR(ret);
347}
348
349/*
350 * mark the data attached to an inode as obsolete due to a write on the server
351 * - might also want to ditch all the outstanding writes and dirty pages
352 */
353void afs_zap_data(struct afs_vnode *vnode)
354{
355	_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
356
357#ifdef CONFIG_AFS_FSCACHE
358	fscache_invalidate(vnode->cache);
359#endif
360
361	/* nuke all the non-dirty pages that aren't locked, mapped or being
362	 * written back in a regular file and completely discard the pages in a
363	 * directory or symlink */
364	if (S_ISREG(vnode->vfs_inode.i_mode))
365		invalidate_remote_inode(&vnode->vfs_inode);
366	else
367		invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
368}
369
370/*
371 * validate a vnode/inode
372 * - there are several things we need to check
373 *   - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
374 *     symlink)
375 *   - parent dir metadata changed (security changes)
376 *   - dentry data changed (write, truncate)
377 *   - dentry metadata changed (security changes)
378 */
379int afs_validate(struct afs_vnode *vnode, struct key *key)
380{
381	time64_t now = ktime_get_real_seconds();
382	bool valid = false;
383	int ret;
384
385	_enter("{v={%x:%u} fl=%lx},%x",
386	       vnode->fid.vid, vnode->fid.vnode, vnode->flags,
387	       key_serial(key));
388
389	/* Quickly check the callback state.  Ideally, we'd use read_seqbegin
390	 * here, but we have no way to pass the net namespace to the RCU
391	 * cleanup for the server record.
392	 */
393	read_seqlock_excl(&vnode->cb_lock);
394
395	if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
396		if (vnode->cb_s_break != vnode->cb_interest->server->cb_s_break ||
397		    vnode->cb_v_break != vnode->volume->cb_v_break) {
398			vnode->cb_s_break = vnode->cb_interest->server->cb_s_break;
399			vnode->cb_v_break = vnode->volume->cb_v_break;
400			valid = false;
401		} else if (vnode->status.type == AFS_FTYPE_DIR &&
402			   test_bit(AFS_VNODE_DIR_VALID, &vnode->flags) &&
403			   vnode->cb_expires_at - 10 > now) {
404			valid = true;
405		} else if (!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags) &&
406			   vnode->cb_expires_at - 10 > now) {
407			valid = true;
408		}
409	} else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
410		valid = true;
411	}
412
413	read_sequnlock_excl(&vnode->cb_lock);
414
415	if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
416		clear_nlink(&vnode->vfs_inode);
417
418	if (valid)
419		goto valid;
420
421	down_write(&vnode->validate_lock);
422
423	/* if the promise has expired, we need to check the server again to get
424	 * a new promise - note that if the (parent) directory's metadata was
425	 * changed then the security may be different and we may no longer have
426	 * access */
427	if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) {
 
428		_debug("not promised");
429		ret = afs_fetch_status(vnode, key, false);
430		if (ret < 0) {
431			if (ret == -ENOENT) {
432				set_bit(AFS_VNODE_DELETED, &vnode->flags);
433				ret = -ESTALE;
434			}
435			goto error_unlock;
436		}
437		_debug("new promise [fl=%lx]", vnode->flags);
438	}
439
440	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
441		_debug("file already deleted");
442		ret = -ESTALE;
443		goto error_unlock;
444	}
445
446	/* if the vnode's data version number changed then its contents are
447	 * different */
448	if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
449		afs_zap_data(vnode);
450	up_write(&vnode->validate_lock);
 
 
451valid:
452	_leave(" = 0");
453	return 0;
454
455error_unlock:
456	up_write(&vnode->validate_lock);
457	_leave(" = %d", ret);
458	return ret;
459}
460
461/*
462 * read the attributes of an inode
463 */
464int afs_getattr(const struct path *path, struct kstat *stat,
465		u32 request_mask, unsigned int query_flags)
466{
467	struct inode *inode = d_inode(path->dentry);
468	struct afs_vnode *vnode = AFS_FS_I(inode);
469	int seq = 0;
470
471	_enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation);
472
473	do {
474		read_seqbegin_or_lock(&vnode->cb_lock, &seq);
475		generic_fillattr(inode, stat);
476	} while (need_seqretry(&vnode->cb_lock, seq));
477
478	done_seqretry(&vnode->cb_lock, seq);
479	return 0;
480}
481
482/*
483 * discard an AFS inode
484 */
485int afs_drop_inode(struct inode *inode)
486{
487	_enter("");
488
489	if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags))
490		return generic_delete_inode(inode);
491	else
492		return generic_drop_inode(inode);
493}
494
495/*
496 * clear an AFS inode
497 */
498void afs_evict_inode(struct inode *inode)
499{
 
500	struct afs_vnode *vnode;
501
502	vnode = AFS_FS_I(inode);
503
504	_enter("{%x:%u.%d}",
505	       vnode->fid.vid,
506	       vnode->fid.vnode,
507	       vnode->fid.unique);
 
 
 
508
509	_debug("CLEAR INODE %p", inode);
510
511	ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
512
513	truncate_inode_pages_final(&inode->i_data);
514	clear_inode(inode);
515
516	if (vnode->cb_interest) {
517		afs_put_cb_interest(afs_i2net(inode), vnode->cb_interest);
518		vnode->cb_interest = NULL;
 
 
 
 
 
519	}
520
521	while (!list_empty(&vnode->wb_keys)) {
522		struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next,
523						    struct afs_wb_key, vnode_link);
524		list_del(&wbk->vnode_link);
525		afs_put_wb_key(wbk);
526	}
527
528#ifdef CONFIG_AFS_FSCACHE
529	{
530		struct afs_vnode_cache_aux aux;
 
531
532		aux.data_version = vnode->status.data_version;
533		fscache_relinquish_cookie(vnode->cache, &aux,
534					  test_bit(AFS_VNODE_DELETED, &vnode->flags));
535		vnode->cache = NULL;
536	}
537#endif
538
539	afs_put_permits(rcu_access_pointer(vnode->permit_cache));
540	_leave("");
541}
542
543/*
544 * set the attributes of an inode
545 */
546int afs_setattr(struct dentry *dentry, struct iattr *attr)
547{
548	struct afs_fs_cursor fc;
549	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
550	struct key *key;
551	int ret;
552
553	_enter("{%x:%u},{n=%pd},%x",
554	       vnode->fid.vid, vnode->fid.vnode, dentry,
555	       attr->ia_valid);
556
557	if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
558				ATTR_MTIME))) {
559		_leave(" = 0 [unsupported]");
560		return 0;
561	}
562
563	/* flush any dirty data outstanding on a regular file */
564	if (S_ISREG(vnode->vfs_inode.i_mode))
565		filemap_write_and_wait(vnode->vfs_inode.i_mapping);
 
 
566
567	if (attr->ia_valid & ATTR_FILE) {
568		key = afs_file_key(attr->ia_file);
569	} else {
570		key = afs_request_key(vnode->volume->cell);
571		if (IS_ERR(key)) {
572			ret = PTR_ERR(key);
573			goto error;
574		}
575	}
576
577	ret = -ERESTARTSYS;
578	if (afs_begin_vnode_operation(&fc, vnode, key)) {
579		while (afs_select_fileserver(&fc)) {
580			fc.cb_break = afs_calc_vnode_cb_break(vnode);
581			afs_fs_setattr(&fc, attr);
582		}
583
584		afs_check_for_remote_deletion(&fc, fc.vnode);
585		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
586		ret = afs_end_vnode_operation(&fc);
587	}
588
589	if (!(attr->ia_valid & ATTR_FILE))
590		key_put(key);
591
592error:
593	_leave(" = %d", ret);
594	return ret;
595}