1 /* -*- c -*- --------------------------------------------------------------- *
3 * linux/fs/autofs/root.c
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
6 * Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
7 * Copyright 2001-2006 Ian Kent <raven@themaw.net>
9 * This file is part of the Linux kernel and is made available under
10 * the terms of the GNU General Public License, version 2, or at your
11 * option, any later version, incorporated herein by reference.
13 * ------------------------------------------------------------------------- */
15 #include <linux/capability.h>
16 #include <linux/errno.h>
17 #include <linux/stat.h>
18 #include <linux/slab.h>
19 #include <linux/param.h>
20 #include <linux/time.h>
21 #include <linux/compat.h>
22 #include <linux/mutex.h>
26 static int autofs4_dir_symlink(struct inode
*,struct dentry
*,const char *);
27 static int autofs4_dir_unlink(struct inode
*,struct dentry
*);
28 static int autofs4_dir_rmdir(struct inode
*,struct dentry
*);
29 static int autofs4_dir_mkdir(struct inode
*,struct dentry
*,umode_t
);
30 static long autofs4_root_ioctl(struct file
*,unsigned int,unsigned long);
32 static long autofs4_root_compat_ioctl(struct file
*,unsigned int,unsigned long);
34 static int autofs4_dir_open(struct inode
*inode
, struct file
*file
);
35 static struct dentry
*autofs4_lookup(struct inode
*,struct dentry
*, unsigned int);
36 static struct vfsmount
*autofs4_d_automount(struct path
*);
37 static int autofs4_d_manage(struct dentry
*, bool);
38 static void autofs4_dentry_release(struct dentry
*);
40 const struct file_operations autofs4_root_operations
= {
41 .open
= dcache_dir_open
,
42 .release
= dcache_dir_close
,
43 .read
= generic_read_dir
,
44 .iterate
= dcache_readdir
,
45 .llseek
= dcache_dir_lseek
,
46 .unlocked_ioctl
= autofs4_root_ioctl
,
48 .compat_ioctl
= autofs4_root_compat_ioctl
,
52 const struct file_operations autofs4_dir_operations
= {
53 .open
= autofs4_dir_open
,
54 .release
= dcache_dir_close
,
55 .read
= generic_read_dir
,
56 .iterate
= dcache_readdir
,
57 .llseek
= dcache_dir_lseek
,
60 const struct inode_operations autofs4_dir_inode_operations
= {
61 .lookup
= autofs4_lookup
,
62 .unlink
= autofs4_dir_unlink
,
63 .symlink
= autofs4_dir_symlink
,
64 .mkdir
= autofs4_dir_mkdir
,
65 .rmdir
= autofs4_dir_rmdir
,
68 const struct dentry_operations autofs4_dentry_operations
= {
69 .d_automount
= autofs4_d_automount
,
70 .d_manage
= autofs4_d_manage
,
71 .d_release
= autofs4_dentry_release
,
74 static void autofs4_add_active(struct dentry
*dentry
)
76 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
77 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
79 spin_lock(&sbi
->lookup_lock
);
80 if (!ino
->active_count
) {
81 if (list_empty(&ino
->active
))
82 list_add(&ino
->active
, &sbi
->active_list
);
85 spin_unlock(&sbi
->lookup_lock
);
90 static void autofs4_del_active(struct dentry
*dentry
)
92 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
93 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
95 spin_lock(&sbi
->lookup_lock
);
97 if (!ino
->active_count
) {
98 if (!list_empty(&ino
->active
))
99 list_del_init(&ino
->active
);
101 spin_unlock(&sbi
->lookup_lock
);
106 static int autofs4_dir_open(struct inode
*inode
, struct file
*file
)
108 struct dentry
*dentry
= file
->f_path
.dentry
;
109 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
111 DPRINTK("file=%p dentry=%p %.*s",
112 file
, dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
114 if (autofs4_oz_mode(sbi
))
118 * An empty directory in an autofs file system is always a
119 * mount point. The daemon must have failed to mount this
120 * during lookup so it doesn't exist. This can happen, for
121 * example, if user space returns an incorrect status for a
122 * mount request. Otherwise we're doing a readdir on the
123 * autofs file system so just let the libfs routines handle
126 spin_lock(&sbi
->lookup_lock
);
127 if (!d_mountpoint(dentry
) && simple_empty(dentry
)) {
128 spin_unlock(&sbi
->lookup_lock
);
131 spin_unlock(&sbi
->lookup_lock
);
134 return dcache_dir_open(inode
, file
);
137 static void autofs4_dentry_release(struct dentry
*de
)
139 struct autofs_info
*ino
= autofs4_dentry_ino(de
);
140 struct autofs_sb_info
*sbi
= autofs4_sbi(de
->d_sb
);
142 DPRINTK("releasing %p", de
);
148 spin_lock(&sbi
->lookup_lock
);
149 if (!list_empty(&ino
->active
))
150 list_del(&ino
->active
);
151 if (!list_empty(&ino
->expiring
))
152 list_del(&ino
->expiring
);
153 spin_unlock(&sbi
->lookup_lock
);
156 autofs4_free_ino(ino
);
159 static struct dentry
*autofs4_lookup_active(struct dentry
*dentry
)
161 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
162 struct dentry
*parent
= dentry
->d_parent
;
163 struct qstr
*name
= &dentry
->d_name
;
164 unsigned int len
= name
->len
;
165 unsigned int hash
= name
->hash
;
166 const unsigned char *str
= name
->name
;
167 struct list_head
*p
, *head
;
169 head
= &sbi
->active_list
;
170 if (list_empty(head
))
172 spin_lock(&sbi
->lookup_lock
);
173 list_for_each(p
, head
) {
174 struct autofs_info
*ino
;
175 struct dentry
*active
;
178 ino
= list_entry(p
, struct autofs_info
, active
);
179 active
= ino
->dentry
;
181 spin_lock(&active
->d_lock
);
184 if ((int) d_count(active
) <= 0)
187 qstr
= &active
->d_name
;
189 if (active
->d_name
.hash
!= hash
)
191 if (active
->d_parent
!= parent
)
194 if (qstr
->len
!= len
)
196 if (memcmp(qstr
->name
, str
, len
))
199 if (d_unhashed(active
)) {
201 spin_unlock(&active
->d_lock
);
202 spin_unlock(&sbi
->lookup_lock
);
206 spin_unlock(&active
->d_lock
);
208 spin_unlock(&sbi
->lookup_lock
);
213 static struct dentry
*autofs4_lookup_expiring(struct dentry
*dentry
,
216 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
217 struct dentry
*parent
= dentry
->d_parent
;
218 struct qstr
*name
= &dentry
->d_name
;
219 unsigned int len
= name
->len
;
220 unsigned int hash
= name
->hash
;
221 const unsigned char *str
= name
->name
;
222 struct list_head
*p
, *head
;
224 head
= &sbi
->expiring_list
;
225 if (list_empty(head
))
227 spin_lock(&sbi
->lookup_lock
);
228 list_for_each(p
, head
) {
229 struct autofs_info
*ino
;
230 struct dentry
*expiring
;
234 spin_unlock(&sbi
->lookup_lock
);
235 return ERR_PTR(-ECHILD
);
238 ino
= list_entry(p
, struct autofs_info
, expiring
);
239 expiring
= ino
->dentry
;
241 spin_lock(&expiring
->d_lock
);
243 /* We've already been dentry_iput or unlinked */
244 if (!expiring
->d_inode
)
247 qstr
= &expiring
->d_name
;
249 if (expiring
->d_name
.hash
!= hash
)
251 if (expiring
->d_parent
!= parent
)
254 if (qstr
->len
!= len
)
256 if (memcmp(qstr
->name
, str
, len
))
259 if (d_unhashed(expiring
)) {
260 dget_dlock(expiring
);
261 spin_unlock(&expiring
->d_lock
);
262 spin_unlock(&sbi
->lookup_lock
);
266 spin_unlock(&expiring
->d_lock
);
268 spin_unlock(&sbi
->lookup_lock
);
273 static int autofs4_mount_wait(struct dentry
*dentry
, bool rcu_walk
)
275 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
276 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
279 if (ino
->flags
& AUTOFS_INF_PENDING
) {
282 DPRINTK("waiting for mount name=%.*s",
283 dentry
->d_name
.len
, dentry
->d_name
.name
);
284 status
= autofs4_wait(sbi
, dentry
, NFY_MOUNT
);
285 DPRINTK("mount wait done status=%d", status
);
287 ino
->last_used
= jiffies
;
291 static int do_expire_wait(struct dentry
*dentry
, bool rcu_walk
)
293 struct dentry
*expiring
;
295 expiring
= autofs4_lookup_expiring(dentry
, rcu_walk
);
296 if (IS_ERR(expiring
))
297 return PTR_ERR(expiring
);
299 return autofs4_expire_wait(dentry
, rcu_walk
);
302 * If we are racing with expire the request might not
303 * be quite complete, but the directory has been removed
304 * so it must have been successful, just wait for it.
306 autofs4_expire_wait(expiring
, 0);
307 autofs4_del_expiring(expiring
);
313 static struct dentry
*autofs4_mountpoint_changed(struct path
*path
)
315 struct dentry
*dentry
= path
->dentry
;
316 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
319 * If this is an indirect mount the dentry could have gone away
320 * as a result of an expire and a new one created.
322 if (autofs_type_indirect(sbi
->type
) && d_unhashed(dentry
)) {
323 struct dentry
*parent
= dentry
->d_parent
;
324 struct autofs_info
*ino
;
325 struct dentry
*new = d_lookup(parent
, &dentry
->d_name
);
328 ino
= autofs4_dentry_ino(new);
329 ino
->last_used
= jiffies
;
336 static struct vfsmount
*autofs4_d_automount(struct path
*path
)
338 struct dentry
*dentry
= path
->dentry
;
339 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
340 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
343 DPRINTK("dentry=%p %.*s",
344 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
346 /* The daemon never triggers a mount. */
347 if (autofs4_oz_mode(sbi
))
351 * If an expire request is pending everyone must wait.
352 * If the expire fails we're still mounted so continue
353 * the follow and return. A return of -EAGAIN (which only
354 * happens with indirect mounts) means the expire completed
355 * and the directory was removed, so just go ahead and try
358 status
= do_expire_wait(dentry
, 0);
359 if (status
&& status
!= -EAGAIN
)
362 /* Callback to the daemon to perform the mount or wait */
363 spin_lock(&sbi
->fs_lock
);
364 if (ino
->flags
& AUTOFS_INF_PENDING
) {
365 spin_unlock(&sbi
->fs_lock
);
366 status
= autofs4_mount_wait(dentry
, 0);
368 return ERR_PTR(status
);
373 * If the dentry is a symlink it's equivalent to a directory
374 * having d_mountpoint() true, so there's no need to call back
377 if (dentry
->d_inode
&& S_ISLNK(dentry
->d_inode
->i_mode
)) {
378 spin_unlock(&sbi
->fs_lock
);
382 if (!d_mountpoint(dentry
)) {
384 * It's possible that user space hasn't removed directories
385 * after umounting a rootless multi-mount, although it
386 * should. For v5 have_submounts() is sufficient to handle
387 * this because the leaves of the directory tree under the
388 * mount never trigger mounts themselves (they have an autofs
389 * trigger mount mounted on them). But v4 pseudo direct mounts
390 * do need the leaves to trigger mounts. In this case we
391 * have no choice but to use the list_empty() check and
392 * require user space behave.
394 if (sbi
->version
> 4) {
395 if (have_submounts(dentry
)) {
396 spin_unlock(&sbi
->fs_lock
);
400 if (!simple_empty(dentry
)) {
401 spin_unlock(&sbi
->fs_lock
);
405 ino
->flags
|= AUTOFS_INF_PENDING
;
406 spin_unlock(&sbi
->fs_lock
);
407 status
= autofs4_mount_wait(dentry
, 0);
408 spin_lock(&sbi
->fs_lock
);
409 ino
->flags
&= ~AUTOFS_INF_PENDING
;
411 spin_unlock(&sbi
->fs_lock
);
412 return ERR_PTR(status
);
415 spin_unlock(&sbi
->fs_lock
);
417 /* Mount succeeded, check if we ended up with a new dentry */
418 dentry
= autofs4_mountpoint_changed(path
);
420 return ERR_PTR(-ENOENT
);
425 static int autofs4_d_manage(struct dentry
*dentry
, bool rcu_walk
)
427 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
428 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
431 DPRINTK("dentry=%p %.*s",
432 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
434 /* The daemon never waits. */
435 if (autofs4_oz_mode(sbi
)) {
436 if (!d_mountpoint(dentry
))
441 /* Wait for pending expires */
442 if (do_expire_wait(dentry
, rcu_walk
) == -ECHILD
)
446 * This dentry may be under construction so wait on mount
449 status
= autofs4_mount_wait(dentry
, rcu_walk
);
454 /* We don't need fs_lock in rcu_walk mode,
455 * just testing 'AUTOFS_INFO_NO_RCU' is enough.
456 * simple_empty() takes a spinlock, so leave it
458 * We only return -EISDIR when certain this isn't
462 if (ino
->flags
& (AUTOFS_INF_EXPIRING
| AUTOFS_INF_NO_RCU
))
464 if (d_mountpoint(dentry
))
466 inode
= ACCESS_ONCE(dentry
->d_inode
);
467 if (inode
&& S_ISLNK(inode
->i_mode
))
469 if (list_empty(&dentry
->d_subdirs
))
471 if (!simple_empty(dentry
))
476 spin_lock(&sbi
->fs_lock
);
478 * If the dentry has been selected for expire while we slept
479 * on the lock then it might go away. We'll deal with that in
480 * ->d_automount() and wait on a new mount if the expire
481 * succeeds or return here if it doesn't (since there's no
482 * mount to follow with a rootless multi-mount).
484 if (!(ino
->flags
& AUTOFS_INF_EXPIRING
)) {
486 * Any needed mounting has been completed and the path
487 * updated so check if this is a rootless multi-mount so
488 * we can avoid needless calls ->d_automount() and avoid
489 * an incorrect ELOOP error return.
491 if ((!d_mountpoint(dentry
) && !simple_empty(dentry
)) ||
492 (dentry
->d_inode
&& S_ISLNK(dentry
->d_inode
->i_mode
)))
495 spin_unlock(&sbi
->fs_lock
);
500 /* Lookups in the root directory */
501 static struct dentry
*autofs4_lookup(struct inode
*dir
, struct dentry
*dentry
, unsigned int flags
)
503 struct autofs_sb_info
*sbi
;
504 struct autofs_info
*ino
;
505 struct dentry
*active
;
507 DPRINTK("name = %.*s", dentry
->d_name
.len
, dentry
->d_name
.name
);
509 /* File name too long to exist */
510 if (dentry
->d_name
.len
> NAME_MAX
)
511 return ERR_PTR(-ENAMETOOLONG
);
513 sbi
= autofs4_sbi(dir
->i_sb
);
515 DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
516 current
->pid
, task_pgrp_nr(current
), sbi
->catatonic
,
517 autofs4_oz_mode(sbi
));
519 active
= autofs4_lookup_active(dentry
);
524 * A dentry that is not within the root can never trigger a
525 * mount operation, unless the directory already exists, so we
526 * can return fail immediately. The daemon however does need
527 * to create directories within the file system.
529 if (!autofs4_oz_mode(sbi
) && !IS_ROOT(dentry
->d_parent
))
530 return ERR_PTR(-ENOENT
);
532 /* Mark entries in the root as mount triggers */
533 if (autofs_type_indirect(sbi
->type
) && IS_ROOT(dentry
->d_parent
))
534 __managed_dentry_set_managed(dentry
);
536 ino
= autofs4_new_ino(sbi
);
538 return ERR_PTR(-ENOMEM
);
540 dentry
->d_fsdata
= ino
;
541 ino
->dentry
= dentry
;
543 autofs4_add_active(dentry
);
545 d_instantiate(dentry
, NULL
);
550 static int autofs4_dir_symlink(struct inode
*dir
,
551 struct dentry
*dentry
,
554 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
555 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
556 struct autofs_info
*p_ino
;
558 size_t size
= strlen(symname
);
561 DPRINTK("%s <- %.*s", symname
,
562 dentry
->d_name
.len
, dentry
->d_name
.name
);
564 if (!autofs4_oz_mode(sbi
))
569 autofs4_clean_ino(ino
);
571 autofs4_del_active(dentry
);
573 cp
= kmalloc(size
+ 1, GFP_KERNEL
);
579 inode
= autofs4_get_inode(dir
->i_sb
, S_IFLNK
| 0555);
582 if (!dentry
->d_fsdata
)
586 inode
->i_private
= cp
;
587 inode
->i_size
= size
;
588 d_add(dentry
, inode
);
591 atomic_inc(&ino
->count
);
592 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
593 if (p_ino
&& !IS_ROOT(dentry
))
594 atomic_inc(&p_ino
->count
);
596 dir
->i_mtime
= CURRENT_TIME
;
604 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
605 * that the file no longer exists. However, doing that means that the
606 * VFS layer can turn the dentry into a negative dentry. We don't want
607 * this, because the unlink is probably the result of an expire.
608 * We simply d_drop it and add it to a expiring list in the super block,
609 * which allows the dentry lookup to check for an incomplete expire.
611 * If a process is blocked on the dentry waiting for the expire to finish,
612 * it will invalidate the dentry and try to mount with a new one.
614 * Also see autofs4_dir_rmdir()..
616 static int autofs4_dir_unlink(struct inode
*dir
, struct dentry
*dentry
)
618 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
619 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
620 struct autofs_info
*p_ino
;
622 /* This allows root to remove symlinks */
623 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
626 if (atomic_dec_and_test(&ino
->count
)) {
627 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
628 if (p_ino
&& !IS_ROOT(dentry
))
629 atomic_dec(&p_ino
->count
);
633 dentry
->d_inode
->i_size
= 0;
634 clear_nlink(dentry
->d_inode
);
636 dir
->i_mtime
= CURRENT_TIME
;
638 spin_lock(&sbi
->lookup_lock
);
639 __autofs4_add_expiring(dentry
);
641 spin_unlock(&sbi
->lookup_lock
);
647 * Version 4 of autofs provides a pseudo direct mount implementation
648 * that relies on directories at the leaves of a directory tree under
649 * an indirect mount to trigger mounts. To allow for this we need to
650 * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
651 * of the directory tree. There is no need to clear the automount flag
652 * following a mount or restore it after an expire because these mounts
653 * are always covered. However, it is necessary to ensure that these
654 * flags are clear on non-empty directories to avoid unnecessary calls
657 static void autofs_set_leaf_automount_flags(struct dentry
*dentry
)
659 struct dentry
*parent
;
661 /* root and dentrys in the root are already handled */
662 if (IS_ROOT(dentry
->d_parent
))
665 managed_dentry_set_managed(dentry
);
667 parent
= dentry
->d_parent
;
668 /* only consider parents below dentrys in the root */
669 if (IS_ROOT(parent
->d_parent
))
671 managed_dentry_clear_managed(parent
);
675 static void autofs_clear_leaf_automount_flags(struct dentry
*dentry
)
677 struct list_head
*d_child
;
678 struct dentry
*parent
;
680 /* flags for dentrys in the root are handled elsewhere */
681 if (IS_ROOT(dentry
->d_parent
))
684 managed_dentry_clear_managed(dentry
);
686 parent
= dentry
->d_parent
;
687 /* only consider parents below dentrys in the root */
688 if (IS_ROOT(parent
->d_parent
))
690 d_child
= &dentry
->d_u
.d_child
;
691 /* Set parent managed if it's becoming empty */
692 if (d_child
->next
== &parent
->d_subdirs
&&
693 d_child
->prev
== &parent
->d_subdirs
)
694 managed_dentry_set_managed(parent
);
698 static int autofs4_dir_rmdir(struct inode
*dir
, struct dentry
*dentry
)
700 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
701 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
702 struct autofs_info
*p_ino
;
704 DPRINTK("dentry %p, removing %.*s",
705 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
707 if (!autofs4_oz_mode(sbi
))
710 spin_lock(&sbi
->lookup_lock
);
711 if (!simple_empty(dentry
)) {
712 spin_unlock(&sbi
->lookup_lock
);
715 __autofs4_add_expiring(dentry
);
717 spin_unlock(&sbi
->lookup_lock
);
719 if (sbi
->version
< 5)
720 autofs_clear_leaf_automount_flags(dentry
);
722 if (atomic_dec_and_test(&ino
->count
)) {
723 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
724 if (p_ino
&& dentry
->d_parent
!= dentry
)
725 atomic_dec(&p_ino
->count
);
728 dentry
->d_inode
->i_size
= 0;
729 clear_nlink(dentry
->d_inode
);
737 static int autofs4_dir_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
739 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
740 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
741 struct autofs_info
*p_ino
;
744 if (!autofs4_oz_mode(sbi
))
747 DPRINTK("dentry %p, creating %.*s",
748 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
752 autofs4_clean_ino(ino
);
754 autofs4_del_active(dentry
);
756 inode
= autofs4_get_inode(dir
->i_sb
, S_IFDIR
| 0555);
759 d_add(dentry
, inode
);
761 if (sbi
->version
< 5)
762 autofs_set_leaf_automount_flags(dentry
);
765 atomic_inc(&ino
->count
);
766 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
767 if (p_ino
&& !IS_ROOT(dentry
))
768 atomic_inc(&p_ino
->count
);
770 dir
->i_mtime
= CURRENT_TIME
;
775 /* Get/set timeout ioctl() operation */
777 static inline int autofs4_compat_get_set_timeout(struct autofs_sb_info
*sbi
,
778 compat_ulong_t __user
*p
)
781 unsigned long ntimeout
;
783 if ((rv
= get_user(ntimeout
, p
)) ||
784 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
787 if (ntimeout
> UINT_MAX
/HZ
)
788 sbi
->exp_timeout
= 0;
790 sbi
->exp_timeout
= ntimeout
* HZ
;
796 static inline int autofs4_get_set_timeout(struct autofs_sb_info
*sbi
,
797 unsigned long __user
*p
)
800 unsigned long ntimeout
;
802 if ((rv
= get_user(ntimeout
, p
)) ||
803 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
806 if (ntimeout
> ULONG_MAX
/HZ
)
807 sbi
->exp_timeout
= 0;
809 sbi
->exp_timeout
= ntimeout
* HZ
;
814 /* Return protocol version */
815 static inline int autofs4_get_protover(struct autofs_sb_info
*sbi
, int __user
*p
)
817 return put_user(sbi
->version
, p
);
820 /* Return protocol sub version */
821 static inline int autofs4_get_protosubver(struct autofs_sb_info
*sbi
, int __user
*p
)
823 return put_user(sbi
->sub_version
, p
);
827 * Tells the daemon whether it can umount the autofs mount.
829 static inline int autofs4_ask_umount(struct vfsmount
*mnt
, int __user
*p
)
836 DPRINTK("returning %d", status
);
838 status
= put_user(status
, p
);
843 /* Identify autofs4_dentries - this is so we can tell if there's
844 an extra dentry refcount or not. We only hold a refcount on the
845 dentry if its non-negative (ie, d_inode != NULL)
847 int is_autofs4_dentry(struct dentry
*dentry
)
849 return dentry
&& dentry
->d_inode
&&
850 dentry
->d_op
== &autofs4_dentry_operations
&&
851 dentry
->d_fsdata
!= NULL
;
855 * ioctl()'s on the root directory is the chief method for the daemon to
856 * generate kernel reactions
858 static int autofs4_root_ioctl_unlocked(struct inode
*inode
, struct file
*filp
,
859 unsigned int cmd
, unsigned long arg
)
861 struct autofs_sb_info
*sbi
= autofs4_sbi(inode
->i_sb
);
862 void __user
*p
= (void __user
*)arg
;
864 DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
865 cmd
,arg
,sbi
,task_pgrp_nr(current
));
867 if (_IOC_TYPE(cmd
) != _IOC_TYPE(AUTOFS_IOC_FIRST
) ||
868 _IOC_NR(cmd
) - _IOC_NR(AUTOFS_IOC_FIRST
) >= AUTOFS_IOC_COUNT
)
871 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
875 case AUTOFS_IOC_READY
: /* Wait queue: go ahead and retry */
876 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,0);
877 case AUTOFS_IOC_FAIL
: /* Wait queue: fail with ENOENT */
878 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,-ENOENT
);
879 case AUTOFS_IOC_CATATONIC
: /* Enter catatonic mode (daemon shutdown) */
880 autofs4_catatonic_mode(sbi
);
882 case AUTOFS_IOC_PROTOVER
: /* Get protocol version */
883 return autofs4_get_protover(sbi
, p
);
884 case AUTOFS_IOC_PROTOSUBVER
: /* Get protocol sub version */
885 return autofs4_get_protosubver(sbi
, p
);
886 case AUTOFS_IOC_SETTIMEOUT
:
887 return autofs4_get_set_timeout(sbi
, p
);
889 case AUTOFS_IOC_SETTIMEOUT32
:
890 return autofs4_compat_get_set_timeout(sbi
, p
);
893 case AUTOFS_IOC_ASKUMOUNT
:
894 return autofs4_ask_umount(filp
->f_path
.mnt
, p
);
896 /* return a single thing to expire */
897 case AUTOFS_IOC_EXPIRE
:
898 return autofs4_expire_run(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
899 /* same as above, but can send multiple expires through pipe */
900 case AUTOFS_IOC_EXPIRE_MULTI
:
901 return autofs4_expire_multi(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
908 static long autofs4_root_ioctl(struct file
*filp
,
909 unsigned int cmd
, unsigned long arg
)
911 struct inode
*inode
= file_inode(filp
);
912 return autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
916 static long autofs4_root_compat_ioctl(struct file
*filp
,
917 unsigned int cmd
, unsigned long arg
)
919 struct inode
*inode
= file_inode(filp
);
922 if (cmd
== AUTOFS_IOC_READY
|| cmd
== AUTOFS_IOC_FAIL
)
923 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
925 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
,
926 (unsigned long)compat_ptr(arg
));