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 %pd", file
, dentry
, dentry
);
113 if (autofs4_oz_mode(sbi
))
117 * An empty directory in an autofs file system is always a
118 * mount point. The daemon must have failed to mount this
119 * during lookup so it doesn't exist. This can happen, for
120 * example, if user space returns an incorrect status for a
121 * mount request. Otherwise we're doing a readdir on the
122 * autofs file system so just let the libfs routines handle
125 spin_lock(&sbi
->lookup_lock
);
126 if (!d_mountpoint(dentry
) && simple_empty(dentry
)) {
127 spin_unlock(&sbi
->lookup_lock
);
130 spin_unlock(&sbi
->lookup_lock
);
133 return dcache_dir_open(inode
, file
);
136 static void autofs4_dentry_release(struct dentry
*de
)
138 struct autofs_info
*ino
= autofs4_dentry_ino(de
);
139 struct autofs_sb_info
*sbi
= autofs4_sbi(de
->d_sb
);
141 DPRINTK("releasing %p", de
);
147 spin_lock(&sbi
->lookup_lock
);
148 if (!list_empty(&ino
->active
))
149 list_del(&ino
->active
);
150 if (!list_empty(&ino
->expiring
))
151 list_del(&ino
->expiring
);
152 spin_unlock(&sbi
->lookup_lock
);
155 autofs4_free_ino(ino
);
158 static struct dentry
*autofs4_lookup_active(struct dentry
*dentry
)
160 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
161 struct dentry
*parent
= dentry
->d_parent
;
162 struct qstr
*name
= &dentry
->d_name
;
163 unsigned int len
= name
->len
;
164 unsigned int hash
= name
->hash
;
165 const unsigned char *str
= name
->name
;
166 struct list_head
*p
, *head
;
168 head
= &sbi
->active_list
;
169 if (list_empty(head
))
171 spin_lock(&sbi
->lookup_lock
);
172 list_for_each(p
, head
) {
173 struct autofs_info
*ino
;
174 struct dentry
*active
;
177 ino
= list_entry(p
, struct autofs_info
, active
);
178 active
= ino
->dentry
;
180 spin_lock(&active
->d_lock
);
183 if ((int) d_count(active
) <= 0)
186 qstr
= &active
->d_name
;
188 if (active
->d_name
.hash
!= hash
)
190 if (active
->d_parent
!= parent
)
193 if (qstr
->len
!= len
)
195 if (memcmp(qstr
->name
, str
, len
))
198 if (d_unhashed(active
)) {
200 spin_unlock(&active
->d_lock
);
201 spin_unlock(&sbi
->lookup_lock
);
205 spin_unlock(&active
->d_lock
);
207 spin_unlock(&sbi
->lookup_lock
);
212 static struct dentry
*autofs4_lookup_expiring(struct dentry
*dentry
,
215 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
216 struct dentry
*parent
= dentry
->d_parent
;
217 struct qstr
*name
= &dentry
->d_name
;
218 unsigned int len
= name
->len
;
219 unsigned int hash
= name
->hash
;
220 const unsigned char *str
= name
->name
;
221 struct list_head
*p
, *head
;
223 head
= &sbi
->expiring_list
;
224 if (list_empty(head
))
226 spin_lock(&sbi
->lookup_lock
);
227 list_for_each(p
, head
) {
228 struct autofs_info
*ino
;
229 struct dentry
*expiring
;
233 spin_unlock(&sbi
->lookup_lock
);
234 return ERR_PTR(-ECHILD
);
237 ino
= list_entry(p
, struct autofs_info
, expiring
);
238 expiring
= ino
->dentry
;
240 spin_lock(&expiring
->d_lock
);
242 /* We've already been dentry_iput or unlinked */
243 if (d_really_is_negative(expiring
))
246 qstr
= &expiring
->d_name
;
248 if (expiring
->d_name
.hash
!= hash
)
250 if (expiring
->d_parent
!= parent
)
253 if (qstr
->len
!= len
)
255 if (memcmp(qstr
->name
, str
, len
))
258 if (d_unhashed(expiring
)) {
259 dget_dlock(expiring
);
260 spin_unlock(&expiring
->d_lock
);
261 spin_unlock(&sbi
->lookup_lock
);
265 spin_unlock(&expiring
->d_lock
);
267 spin_unlock(&sbi
->lookup_lock
);
272 static int autofs4_mount_wait(struct dentry
*dentry
, bool rcu_walk
)
274 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
275 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
278 if (ino
->flags
& AUTOFS_INF_PENDING
) {
281 DPRINTK("waiting for mount name=%pd", dentry
);
282 status
= autofs4_wait(sbi
, dentry
, NFY_MOUNT
);
283 DPRINTK("mount wait done status=%d", status
);
285 ino
->last_used
= jiffies
;
289 static int do_expire_wait(struct dentry
*dentry
, bool rcu_walk
)
291 struct dentry
*expiring
;
293 expiring
= autofs4_lookup_expiring(dentry
, rcu_walk
);
294 if (IS_ERR(expiring
))
295 return PTR_ERR(expiring
);
297 return autofs4_expire_wait(dentry
, rcu_walk
);
300 * If we are racing with expire the request might not
301 * be quite complete, but the directory has been removed
302 * so it must have been successful, just wait for it.
304 autofs4_expire_wait(expiring
, 0);
305 autofs4_del_expiring(expiring
);
311 static struct dentry
*autofs4_mountpoint_changed(struct path
*path
)
313 struct dentry
*dentry
= path
->dentry
;
314 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
317 * If this is an indirect mount the dentry could have gone away
318 * as a result of an expire and a new one created.
320 if (autofs_type_indirect(sbi
->type
) && d_unhashed(dentry
)) {
321 struct dentry
*parent
= dentry
->d_parent
;
322 struct autofs_info
*ino
;
323 struct dentry
*new = d_lookup(parent
, &dentry
->d_name
);
326 ino
= autofs4_dentry_ino(new);
327 ino
->last_used
= jiffies
;
334 static struct vfsmount
*autofs4_d_automount(struct path
*path
)
336 struct dentry
*dentry
= path
->dentry
;
337 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
338 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
341 DPRINTK("dentry=%p %pd", dentry
, dentry
);
343 /* The daemon never triggers a mount. */
344 if (autofs4_oz_mode(sbi
))
348 * If an expire request is pending everyone must wait.
349 * If the expire fails we're still mounted so continue
350 * the follow and return. A return of -EAGAIN (which only
351 * happens with indirect mounts) means the expire completed
352 * and the directory was removed, so just go ahead and try
355 status
= do_expire_wait(dentry
, 0);
356 if (status
&& status
!= -EAGAIN
)
359 /* Callback to the daemon to perform the mount or wait */
360 spin_lock(&sbi
->fs_lock
);
361 if (ino
->flags
& AUTOFS_INF_PENDING
) {
362 spin_unlock(&sbi
->fs_lock
);
363 status
= autofs4_mount_wait(dentry
, 0);
365 return ERR_PTR(status
);
370 * If the dentry is a symlink it's equivalent to a directory
371 * having d_mountpoint() true, so there's no need to call back
374 if (d_really_is_positive(dentry
) && d_is_symlink(dentry
)) {
375 spin_unlock(&sbi
->fs_lock
);
379 if (!d_mountpoint(dentry
)) {
381 * It's possible that user space hasn't removed directories
382 * after umounting a rootless multi-mount, although it
383 * should. For v5 have_submounts() is sufficient to handle
384 * this because the leaves of the directory tree under the
385 * mount never trigger mounts themselves (they have an autofs
386 * trigger mount mounted on them). But v4 pseudo direct mounts
387 * do need the leaves to trigger mounts. In this case we
388 * have no choice but to use the list_empty() check and
389 * require user space behave.
391 if (sbi
->version
> 4) {
392 if (have_submounts(dentry
)) {
393 spin_unlock(&sbi
->fs_lock
);
397 if (!simple_empty(dentry
)) {
398 spin_unlock(&sbi
->fs_lock
);
402 ino
->flags
|= AUTOFS_INF_PENDING
;
403 spin_unlock(&sbi
->fs_lock
);
404 status
= autofs4_mount_wait(dentry
, 0);
405 spin_lock(&sbi
->fs_lock
);
406 ino
->flags
&= ~AUTOFS_INF_PENDING
;
408 spin_unlock(&sbi
->fs_lock
);
409 return ERR_PTR(status
);
412 spin_unlock(&sbi
->fs_lock
);
414 /* Mount succeeded, check if we ended up with a new dentry */
415 dentry
= autofs4_mountpoint_changed(path
);
417 return ERR_PTR(-ENOENT
);
422 static int autofs4_d_manage(struct dentry
*dentry
, bool rcu_walk
)
424 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
425 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
428 DPRINTK("dentry=%p %pd", dentry
, dentry
);
430 /* The daemon never waits. */
431 if (autofs4_oz_mode(sbi
)) {
432 if (!d_mountpoint(dentry
))
437 /* Wait for pending expires */
438 if (do_expire_wait(dentry
, rcu_walk
) == -ECHILD
)
442 * This dentry may be under construction so wait on mount
445 status
= autofs4_mount_wait(dentry
, rcu_walk
);
450 /* We don't need fs_lock in rcu_walk mode,
451 * just testing 'AUTOFS_INFO_NO_RCU' is enough.
452 * simple_empty() takes a spinlock, so leave it
454 * We only return -EISDIR when certain this isn't
458 if (ino
->flags
& (AUTOFS_INF_EXPIRING
| AUTOFS_INF_NO_RCU
))
460 if (d_mountpoint(dentry
))
462 inode
= d_inode_rcu(dentry
);
463 if (inode
&& S_ISLNK(inode
->i_mode
))
465 if (list_empty(&dentry
->d_subdirs
))
467 if (!simple_empty(dentry
))
472 spin_lock(&sbi
->fs_lock
);
474 * If the dentry has been selected for expire while we slept
475 * on the lock then it might go away. We'll deal with that in
476 * ->d_automount() and wait on a new mount if the expire
477 * succeeds or return here if it doesn't (since there's no
478 * mount to follow with a rootless multi-mount).
480 if (!(ino
->flags
& AUTOFS_INF_EXPIRING
)) {
482 * Any needed mounting has been completed and the path
483 * updated so check if this is a rootless multi-mount so
484 * we can avoid needless calls ->d_automount() and avoid
485 * an incorrect ELOOP error return.
487 if ((!d_mountpoint(dentry
) && !simple_empty(dentry
)) ||
488 (d_really_is_positive(dentry
) && d_is_symlink(dentry
)))
491 spin_unlock(&sbi
->fs_lock
);
496 /* Lookups in the root directory */
497 static struct dentry
*autofs4_lookup(struct inode
*dir
, struct dentry
*dentry
, unsigned int flags
)
499 struct autofs_sb_info
*sbi
;
500 struct autofs_info
*ino
;
501 struct dentry
*active
;
503 DPRINTK("name = %pd", dentry
);
505 /* File name too long to exist */
506 if (dentry
->d_name
.len
> NAME_MAX
)
507 return ERR_PTR(-ENAMETOOLONG
);
509 sbi
= autofs4_sbi(dir
->i_sb
);
511 DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
512 current
->pid
, task_pgrp_nr(current
), sbi
->catatonic
,
513 autofs4_oz_mode(sbi
));
515 active
= autofs4_lookup_active(dentry
);
520 * A dentry that is not within the root can never trigger a
521 * mount operation, unless the directory already exists, so we
522 * can return fail immediately. The daemon however does need
523 * to create directories within the file system.
525 if (!autofs4_oz_mode(sbi
) && !IS_ROOT(dentry
->d_parent
))
526 return ERR_PTR(-ENOENT
);
528 /* Mark entries in the root as mount triggers */
529 if (autofs_type_indirect(sbi
->type
) && IS_ROOT(dentry
->d_parent
))
530 __managed_dentry_set_managed(dentry
);
532 ino
= autofs4_new_ino(sbi
);
534 return ERR_PTR(-ENOMEM
);
536 dentry
->d_fsdata
= ino
;
537 ino
->dentry
= dentry
;
539 autofs4_add_active(dentry
);
544 static int autofs4_dir_symlink(struct inode
*dir
,
545 struct dentry
*dentry
,
548 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
549 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
550 struct autofs_info
*p_ino
;
552 size_t size
= strlen(symname
);
555 DPRINTK("%s <- %pd", symname
, dentry
);
557 if (!autofs4_oz_mode(sbi
))
562 autofs4_clean_ino(ino
);
564 autofs4_del_active(dentry
);
566 cp
= kmalloc(size
+ 1, GFP_KERNEL
);
572 inode
= autofs4_get_inode(dir
->i_sb
, S_IFLNK
| 0555);
575 if (!dentry
->d_fsdata
)
579 inode
->i_private
= cp
;
580 inode
->i_size
= size
;
581 d_add(dentry
, inode
);
584 atomic_inc(&ino
->count
);
585 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
586 if (p_ino
&& !IS_ROOT(dentry
))
587 atomic_inc(&p_ino
->count
);
589 dir
->i_mtime
= CURRENT_TIME
;
597 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
598 * that the file no longer exists. However, doing that means that the
599 * VFS layer can turn the dentry into a negative dentry. We don't want
600 * this, because the unlink is probably the result of an expire.
601 * We simply d_drop it and add it to a expiring list in the super block,
602 * which allows the dentry lookup to check for an incomplete expire.
604 * If a process is blocked on the dentry waiting for the expire to finish,
605 * it will invalidate the dentry and try to mount with a new one.
607 * Also see autofs4_dir_rmdir()..
609 static int autofs4_dir_unlink(struct inode
*dir
, struct dentry
*dentry
)
611 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
612 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
613 struct autofs_info
*p_ino
;
615 /* This allows root to remove symlinks */
616 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
619 if (atomic_dec_and_test(&ino
->count
)) {
620 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
621 if (p_ino
&& !IS_ROOT(dentry
))
622 atomic_dec(&p_ino
->count
);
626 d_inode(dentry
)->i_size
= 0;
627 clear_nlink(d_inode(dentry
));
629 dir
->i_mtime
= CURRENT_TIME
;
631 spin_lock(&sbi
->lookup_lock
);
632 __autofs4_add_expiring(dentry
);
634 spin_unlock(&sbi
->lookup_lock
);
640 * Version 4 of autofs provides a pseudo direct mount implementation
641 * that relies on directories at the leaves of a directory tree under
642 * an indirect mount to trigger mounts. To allow for this we need to
643 * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
644 * of the directory tree. There is no need to clear the automount flag
645 * following a mount or restore it after an expire because these mounts
646 * are always covered. However, it is necessary to ensure that these
647 * flags are clear on non-empty directories to avoid unnecessary calls
650 static void autofs_set_leaf_automount_flags(struct dentry
*dentry
)
652 struct dentry
*parent
;
654 /* root and dentrys in the root are already handled */
655 if (IS_ROOT(dentry
->d_parent
))
658 managed_dentry_set_managed(dentry
);
660 parent
= dentry
->d_parent
;
661 /* only consider parents below dentrys in the root */
662 if (IS_ROOT(parent
->d_parent
))
664 managed_dentry_clear_managed(parent
);
668 static void autofs_clear_leaf_automount_flags(struct dentry
*dentry
)
670 struct list_head
*d_child
;
671 struct dentry
*parent
;
673 /* flags for dentrys in the root are handled elsewhere */
674 if (IS_ROOT(dentry
->d_parent
))
677 managed_dentry_clear_managed(dentry
);
679 parent
= dentry
->d_parent
;
680 /* only consider parents below dentrys in the root */
681 if (IS_ROOT(parent
->d_parent
))
683 d_child
= &dentry
->d_child
;
684 /* Set parent managed if it's becoming empty */
685 if (d_child
->next
== &parent
->d_subdirs
&&
686 d_child
->prev
== &parent
->d_subdirs
)
687 managed_dentry_set_managed(parent
);
691 static int autofs4_dir_rmdir(struct inode
*dir
, struct dentry
*dentry
)
693 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
694 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
695 struct autofs_info
*p_ino
;
697 DPRINTK("dentry %p, removing %pd", dentry
, dentry
);
699 if (!autofs4_oz_mode(sbi
))
702 spin_lock(&sbi
->lookup_lock
);
703 if (!simple_empty(dentry
)) {
704 spin_unlock(&sbi
->lookup_lock
);
707 __autofs4_add_expiring(dentry
);
709 spin_unlock(&sbi
->lookup_lock
);
711 if (sbi
->version
< 5)
712 autofs_clear_leaf_automount_flags(dentry
);
714 if (atomic_dec_and_test(&ino
->count
)) {
715 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
716 if (p_ino
&& dentry
->d_parent
!= dentry
)
717 atomic_dec(&p_ino
->count
);
720 d_inode(dentry
)->i_size
= 0;
721 clear_nlink(d_inode(dentry
));
729 static int autofs4_dir_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
731 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
732 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
733 struct autofs_info
*p_ino
;
736 if (!autofs4_oz_mode(sbi
))
739 DPRINTK("dentry %p, creating %pd", dentry
, dentry
);
743 autofs4_clean_ino(ino
);
745 autofs4_del_active(dentry
);
747 inode
= autofs4_get_inode(dir
->i_sb
, S_IFDIR
| 0555);
750 d_add(dentry
, inode
);
752 if (sbi
->version
< 5)
753 autofs_set_leaf_automount_flags(dentry
);
756 atomic_inc(&ino
->count
);
757 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
758 if (p_ino
&& !IS_ROOT(dentry
))
759 atomic_inc(&p_ino
->count
);
761 dir
->i_mtime
= CURRENT_TIME
;
766 /* Get/set timeout ioctl() operation */
768 static inline int autofs4_compat_get_set_timeout(struct autofs_sb_info
*sbi
,
769 compat_ulong_t __user
*p
)
772 unsigned long ntimeout
;
774 if ((rv
= get_user(ntimeout
, p
)) ||
775 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
778 if (ntimeout
> UINT_MAX
/HZ
)
779 sbi
->exp_timeout
= 0;
781 sbi
->exp_timeout
= ntimeout
* HZ
;
787 static inline int autofs4_get_set_timeout(struct autofs_sb_info
*sbi
,
788 unsigned long __user
*p
)
791 unsigned long ntimeout
;
793 if ((rv
= get_user(ntimeout
, p
)) ||
794 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
797 if (ntimeout
> ULONG_MAX
/HZ
)
798 sbi
->exp_timeout
= 0;
800 sbi
->exp_timeout
= ntimeout
* HZ
;
805 /* Return protocol version */
806 static inline int autofs4_get_protover(struct autofs_sb_info
*sbi
, int __user
*p
)
808 return put_user(sbi
->version
, p
);
811 /* Return protocol sub version */
812 static inline int autofs4_get_protosubver(struct autofs_sb_info
*sbi
, int __user
*p
)
814 return put_user(sbi
->sub_version
, p
);
818 * Tells the daemon whether it can umount the autofs mount.
820 static inline int autofs4_ask_umount(struct vfsmount
*mnt
, int __user
*p
)
827 DPRINTK("returning %d", status
);
829 status
= put_user(status
, p
);
834 /* Identify autofs4_dentries - this is so we can tell if there's
835 an extra dentry refcount or not. We only hold a refcount on the
836 dentry if its non-negative (ie, d_inode != NULL)
838 int is_autofs4_dentry(struct dentry
*dentry
)
840 return dentry
&& d_really_is_positive(dentry
) &&
841 dentry
->d_op
== &autofs4_dentry_operations
&&
842 dentry
->d_fsdata
!= NULL
;
846 * ioctl()'s on the root directory is the chief method for the daemon to
847 * generate kernel reactions
849 static int autofs4_root_ioctl_unlocked(struct inode
*inode
, struct file
*filp
,
850 unsigned int cmd
, unsigned long arg
)
852 struct autofs_sb_info
*sbi
= autofs4_sbi(inode
->i_sb
);
853 void __user
*p
= (void __user
*)arg
;
855 DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
856 cmd
,arg
,sbi
,task_pgrp_nr(current
));
858 if (_IOC_TYPE(cmd
) != _IOC_TYPE(AUTOFS_IOC_FIRST
) ||
859 _IOC_NR(cmd
) - _IOC_NR(AUTOFS_IOC_FIRST
) >= AUTOFS_IOC_COUNT
)
862 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
866 case AUTOFS_IOC_READY
: /* Wait queue: go ahead and retry */
867 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,0);
868 case AUTOFS_IOC_FAIL
: /* Wait queue: fail with ENOENT */
869 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,-ENOENT
);
870 case AUTOFS_IOC_CATATONIC
: /* Enter catatonic mode (daemon shutdown) */
871 autofs4_catatonic_mode(sbi
);
873 case AUTOFS_IOC_PROTOVER
: /* Get protocol version */
874 return autofs4_get_protover(sbi
, p
);
875 case AUTOFS_IOC_PROTOSUBVER
: /* Get protocol sub version */
876 return autofs4_get_protosubver(sbi
, p
);
877 case AUTOFS_IOC_SETTIMEOUT
:
878 return autofs4_get_set_timeout(sbi
, p
);
880 case AUTOFS_IOC_SETTIMEOUT32
:
881 return autofs4_compat_get_set_timeout(sbi
, p
);
884 case AUTOFS_IOC_ASKUMOUNT
:
885 return autofs4_ask_umount(filp
->f_path
.mnt
, p
);
887 /* return a single thing to expire */
888 case AUTOFS_IOC_EXPIRE
:
889 return autofs4_expire_run(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
890 /* same as above, but can send multiple expires through pipe */
891 case AUTOFS_IOC_EXPIRE_MULTI
:
892 return autofs4_expire_multi(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
899 static long autofs4_root_ioctl(struct file
*filp
,
900 unsigned int cmd
, unsigned long arg
)
902 struct inode
*inode
= file_inode(filp
);
903 return autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
907 static long autofs4_root_compat_ioctl(struct file
*filp
,
908 unsigned int cmd
, unsigned long arg
)
910 struct inode
*inode
= file_inode(filp
);
913 if (cmd
== AUTOFS_IOC_READY
|| cmd
== AUTOFS_IOC_FAIL
)
914 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
916 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
,
917 (unsigned long)compat_ptr(arg
));