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 .readdir
= 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 .readdir
= 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 spin_lock(&sbi
->lookup_lock
);
170 head
= &sbi
->active_list
;
171 list_for_each(p
, head
) {
172 struct autofs_info
*ino
;
173 struct dentry
*active
;
176 ino
= list_entry(p
, struct autofs_info
, active
);
177 active
= ino
->dentry
;
179 spin_lock(&active
->d_lock
);
182 if (active
->d_count
== 0)
185 qstr
= &active
->d_name
;
187 if (active
->d_name
.hash
!= hash
)
189 if (active
->d_parent
!= parent
)
192 if (qstr
->len
!= len
)
194 if (memcmp(qstr
->name
, str
, len
))
197 if (d_unhashed(active
)) {
199 spin_unlock(&active
->d_lock
);
200 spin_unlock(&sbi
->lookup_lock
);
204 spin_unlock(&active
->d_lock
);
206 spin_unlock(&sbi
->lookup_lock
);
211 static struct dentry
*autofs4_lookup_expiring(struct dentry
*dentry
)
213 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
214 struct dentry
*parent
= dentry
->d_parent
;
215 struct qstr
*name
= &dentry
->d_name
;
216 unsigned int len
= name
->len
;
217 unsigned int hash
= name
->hash
;
218 const unsigned char *str
= name
->name
;
219 struct list_head
*p
, *head
;
221 spin_lock(&sbi
->lookup_lock
);
222 head
= &sbi
->expiring_list
;
223 list_for_each(p
, head
) {
224 struct autofs_info
*ino
;
225 struct dentry
*expiring
;
228 ino
= list_entry(p
, struct autofs_info
, expiring
);
229 expiring
= ino
->dentry
;
231 spin_lock(&expiring
->d_lock
);
233 /* Bad luck, we've already been dentry_iput */
234 if (!expiring
->d_inode
)
237 qstr
= &expiring
->d_name
;
239 if (expiring
->d_name
.hash
!= hash
)
241 if (expiring
->d_parent
!= parent
)
244 if (qstr
->len
!= len
)
246 if (memcmp(qstr
->name
, str
, len
))
249 if (d_unhashed(expiring
)) {
250 dget_dlock(expiring
);
251 spin_unlock(&expiring
->d_lock
);
252 spin_unlock(&sbi
->lookup_lock
);
256 spin_unlock(&expiring
->d_lock
);
258 spin_unlock(&sbi
->lookup_lock
);
263 static int autofs4_mount_wait(struct dentry
*dentry
)
265 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
266 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
269 if (ino
->flags
& AUTOFS_INF_PENDING
) {
270 DPRINTK("waiting for mount name=%.*s",
271 dentry
->d_name
.len
, dentry
->d_name
.name
);
272 status
= autofs4_wait(sbi
, dentry
, NFY_MOUNT
);
273 DPRINTK("mount wait done status=%d", status
);
275 ino
->last_used
= jiffies
;
279 static int do_expire_wait(struct dentry
*dentry
)
281 struct dentry
*expiring
;
283 expiring
= autofs4_lookup_expiring(dentry
);
285 return autofs4_expire_wait(dentry
);
288 * If we are racing with expire the request might not
289 * be quite complete, but the directory has been removed
290 * so it must have been successful, just wait for it.
292 autofs4_expire_wait(expiring
);
293 autofs4_del_expiring(expiring
);
299 static struct dentry
*autofs4_mountpoint_changed(struct path
*path
)
301 struct dentry
*dentry
= path
->dentry
;
302 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
305 * If this is an indirect mount the dentry could have gone away
306 * as a result of an expire and a new one created.
308 if (autofs_type_indirect(sbi
->type
) && d_unhashed(dentry
)) {
309 struct dentry
*parent
= dentry
->d_parent
;
310 struct autofs_info
*ino
;
311 struct dentry
*new = d_lookup(parent
, &dentry
->d_name
);
314 ino
= autofs4_dentry_ino(new);
315 ino
->last_used
= jiffies
;
322 static struct vfsmount
*autofs4_d_automount(struct path
*path
)
324 struct dentry
*dentry
= path
->dentry
;
325 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
326 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
329 DPRINTK("dentry=%p %.*s",
330 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
332 /* The daemon never triggers a mount. */
333 if (autofs4_oz_mode(sbi
))
337 * If an expire request is pending everyone must wait.
338 * If the expire fails we're still mounted so continue
339 * the follow and return. A return of -EAGAIN (which only
340 * happens with indirect mounts) means the expire completed
341 * and the directory was removed, so just go ahead and try
344 status
= do_expire_wait(dentry
);
345 if (status
&& status
!= -EAGAIN
)
348 /* Callback to the daemon to perform the mount or wait */
349 spin_lock(&sbi
->fs_lock
);
350 if (ino
->flags
& AUTOFS_INF_PENDING
) {
351 spin_unlock(&sbi
->fs_lock
);
352 status
= autofs4_mount_wait(dentry
);
354 return ERR_PTR(status
);
359 * If the dentry is a symlink it's equivalent to a directory
360 * having d_mountpoint() true, so there's no need to call back
363 if (dentry
->d_inode
&& S_ISLNK(dentry
->d_inode
->i_mode
)) {
364 spin_unlock(&sbi
->fs_lock
);
368 if (!d_mountpoint(dentry
)) {
370 * It's possible that user space hasn't removed directories
371 * after umounting a rootless multi-mount, although it
372 * should. For v5 have_submounts() is sufficient to handle
373 * this because the leaves of the directory tree under the
374 * mount never trigger mounts themselves (they have an autofs
375 * trigger mount mounted on them). But v4 pseudo direct mounts
376 * do need the leaves to to trigger mounts. In this case we
377 * have no choice but to use the list_empty() check and
378 * require user space behave.
380 if (sbi
->version
> 4) {
381 if (have_submounts(dentry
)) {
382 spin_unlock(&sbi
->fs_lock
);
386 if (!simple_empty(dentry
)) {
387 spin_unlock(&sbi
->fs_lock
);
391 ino
->flags
|= AUTOFS_INF_PENDING
;
392 spin_unlock(&sbi
->fs_lock
);
393 status
= autofs4_mount_wait(dentry
);
394 spin_lock(&sbi
->fs_lock
);
395 ino
->flags
&= ~AUTOFS_INF_PENDING
;
397 spin_unlock(&sbi
->fs_lock
);
398 return ERR_PTR(status
);
401 spin_unlock(&sbi
->fs_lock
);
403 /* Mount succeeded, check if we ended up with a new dentry */
404 dentry
= autofs4_mountpoint_changed(path
);
406 return ERR_PTR(-ENOENT
);
411 static int autofs4_d_manage(struct dentry
*dentry
, bool rcu_walk
)
413 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
414 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
417 DPRINTK("dentry=%p %.*s",
418 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
420 /* The daemon never waits. */
421 if (autofs4_oz_mode(sbi
)) {
424 if (!d_mountpoint(dentry
))
429 /* We need to sleep, so we need pathwalk to be in ref-mode */
433 /* Wait for pending expires */
434 do_expire_wait(dentry
);
437 * This dentry may be under construction so wait on mount
440 status
= autofs4_mount_wait(dentry
);
444 spin_lock(&sbi
->fs_lock
);
446 * If the dentry has been selected for expire while we slept
447 * on the lock then it might go away. We'll deal with that in
448 * ->d_automount() and wait on a new mount if the expire
449 * succeeds or return here if it doesn't (since there's no
450 * mount to follow with a rootless multi-mount).
452 if (!(ino
->flags
& AUTOFS_INF_EXPIRING
)) {
454 * Any needed mounting has been completed and the path
455 * updated so check if this is a rootless multi-mount so
456 * we can avoid needless calls ->d_automount() and avoid
457 * an incorrect ELOOP error return.
459 if ((!d_mountpoint(dentry
) && !simple_empty(dentry
)) ||
460 (dentry
->d_inode
&& S_ISLNK(dentry
->d_inode
->i_mode
)))
463 spin_unlock(&sbi
->fs_lock
);
468 /* Lookups in the root directory */
469 static struct dentry
*autofs4_lookup(struct inode
*dir
, struct dentry
*dentry
, unsigned int flags
)
471 struct autofs_sb_info
*sbi
;
472 struct autofs_info
*ino
;
473 struct dentry
*active
;
475 DPRINTK("name = %.*s", dentry
->d_name
.len
, dentry
->d_name
.name
);
477 /* File name too long to exist */
478 if (dentry
->d_name
.len
> NAME_MAX
)
479 return ERR_PTR(-ENAMETOOLONG
);
481 sbi
= autofs4_sbi(dir
->i_sb
);
483 DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
484 current
->pid
, task_pgrp_nr(current
), sbi
->catatonic
,
485 autofs4_oz_mode(sbi
));
487 active
= autofs4_lookup_active(dentry
);
492 * A dentry that is not within the root can never trigger a
493 * mount operation, unless the directory already exists, so we
494 * can return fail immediately. The daemon however does need
495 * to create directories within the file system.
497 if (!autofs4_oz_mode(sbi
) && !IS_ROOT(dentry
->d_parent
))
498 return ERR_PTR(-ENOENT
);
500 /* Mark entries in the root as mount triggers */
501 if (autofs_type_indirect(sbi
->type
) && IS_ROOT(dentry
->d_parent
))
502 __managed_dentry_set_managed(dentry
);
504 ino
= autofs4_new_ino(sbi
);
506 return ERR_PTR(-ENOMEM
);
508 dentry
->d_fsdata
= ino
;
509 ino
->dentry
= dentry
;
511 autofs4_add_active(dentry
);
513 d_instantiate(dentry
, NULL
);
518 static int autofs4_dir_symlink(struct inode
*dir
,
519 struct dentry
*dentry
,
522 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
523 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
524 struct autofs_info
*p_ino
;
526 size_t size
= strlen(symname
);
529 DPRINTK("%s <- %.*s", symname
,
530 dentry
->d_name
.len
, dentry
->d_name
.name
);
532 if (!autofs4_oz_mode(sbi
))
537 autofs4_clean_ino(ino
);
539 autofs4_del_active(dentry
);
541 cp
= kmalloc(size
+ 1, GFP_KERNEL
);
547 inode
= autofs4_get_inode(dir
->i_sb
, S_IFLNK
| 0555);
550 if (!dentry
->d_fsdata
)
554 inode
->i_private
= cp
;
555 inode
->i_size
= size
;
556 d_add(dentry
, inode
);
559 atomic_inc(&ino
->count
);
560 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
561 if (p_ino
&& dentry
->d_parent
!= dentry
)
562 atomic_inc(&p_ino
->count
);
564 dir
->i_mtime
= CURRENT_TIME
;
572 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
573 * that the file no longer exists. However, doing that means that the
574 * VFS layer can turn the dentry into a negative dentry. We don't want
575 * this, because the unlink is probably the result of an expire.
576 * We simply d_drop it and add it to a expiring list in the super block,
577 * which allows the dentry lookup to check for an incomplete expire.
579 * If a process is blocked on the dentry waiting for the expire to finish,
580 * it will invalidate the dentry and try to mount with a new one.
582 * Also see autofs4_dir_rmdir()..
584 static int autofs4_dir_unlink(struct inode
*dir
, struct dentry
*dentry
)
586 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
587 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
588 struct autofs_info
*p_ino
;
590 /* This allows root to remove symlinks */
591 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
594 if (atomic_dec_and_test(&ino
->count
)) {
595 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
596 if (p_ino
&& dentry
->d_parent
!= dentry
)
597 atomic_dec(&p_ino
->count
);
601 dentry
->d_inode
->i_size
= 0;
602 clear_nlink(dentry
->d_inode
);
604 dir
->i_mtime
= CURRENT_TIME
;
606 spin_lock(&sbi
->lookup_lock
);
607 __autofs4_add_expiring(dentry
);
609 spin_unlock(&sbi
->lookup_lock
);
615 * Version 4 of autofs provides a pseudo direct mount implementation
616 * that relies on directories at the leaves of a directory tree under
617 * an indirect mount to trigger mounts. To allow for this we need to
618 * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
619 * of the directory tree. There is no need to clear the automount flag
620 * following a mount or restore it after an expire because these mounts
621 * are always covered. However, it is necessary to ensure that these
622 * flags are clear on non-empty directories to avoid unnecessary calls
625 static void autofs_set_leaf_automount_flags(struct dentry
*dentry
)
627 struct dentry
*parent
;
629 /* root and dentrys in the root are already handled */
630 if (IS_ROOT(dentry
->d_parent
))
633 managed_dentry_set_managed(dentry
);
635 parent
= dentry
->d_parent
;
636 /* only consider parents below dentrys in the root */
637 if (IS_ROOT(parent
->d_parent
))
639 managed_dentry_clear_managed(parent
);
643 static void autofs_clear_leaf_automount_flags(struct dentry
*dentry
)
645 struct list_head
*d_child
;
646 struct dentry
*parent
;
648 /* flags for dentrys in the root are handled elsewhere */
649 if (IS_ROOT(dentry
->d_parent
))
652 managed_dentry_clear_managed(dentry
);
654 parent
= dentry
->d_parent
;
655 /* only consider parents below dentrys in the root */
656 if (IS_ROOT(parent
->d_parent
))
658 d_child
= &dentry
->d_u
.d_child
;
659 /* Set parent managed if it's becoming empty */
660 if (d_child
->next
== &parent
->d_subdirs
&&
661 d_child
->prev
== &parent
->d_subdirs
)
662 managed_dentry_set_managed(parent
);
666 static int autofs4_dir_rmdir(struct inode
*dir
, struct dentry
*dentry
)
668 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
669 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
670 struct autofs_info
*p_ino
;
672 DPRINTK("dentry %p, removing %.*s",
673 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
675 if (!autofs4_oz_mode(sbi
))
678 spin_lock(&sbi
->lookup_lock
);
679 if (!simple_empty(dentry
)) {
680 spin_unlock(&sbi
->lookup_lock
);
683 __autofs4_add_expiring(dentry
);
685 spin_unlock(&sbi
->lookup_lock
);
687 if (sbi
->version
< 5)
688 autofs_clear_leaf_automount_flags(dentry
);
690 if (atomic_dec_and_test(&ino
->count
)) {
691 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
692 if (p_ino
&& dentry
->d_parent
!= dentry
)
693 atomic_dec(&p_ino
->count
);
696 dentry
->d_inode
->i_size
= 0;
697 clear_nlink(dentry
->d_inode
);
705 static int autofs4_dir_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
707 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
708 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
709 struct autofs_info
*p_ino
;
712 if (!autofs4_oz_mode(sbi
))
715 DPRINTK("dentry %p, creating %.*s",
716 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
720 autofs4_clean_ino(ino
);
722 autofs4_del_active(dentry
);
724 inode
= autofs4_get_inode(dir
->i_sb
, S_IFDIR
| 0555);
727 d_add(dentry
, inode
);
729 if (sbi
->version
< 5)
730 autofs_set_leaf_automount_flags(dentry
);
733 atomic_inc(&ino
->count
);
734 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
735 if (p_ino
&& dentry
->d_parent
!= dentry
)
736 atomic_inc(&p_ino
->count
);
738 dir
->i_mtime
= CURRENT_TIME
;
743 /* Get/set timeout ioctl() operation */
745 static inline int autofs4_compat_get_set_timeout(struct autofs_sb_info
*sbi
,
746 compat_ulong_t __user
*p
)
749 unsigned long ntimeout
;
751 if ((rv
= get_user(ntimeout
, p
)) ||
752 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
755 if (ntimeout
> UINT_MAX
/HZ
)
756 sbi
->exp_timeout
= 0;
758 sbi
->exp_timeout
= ntimeout
* HZ
;
764 static inline int autofs4_get_set_timeout(struct autofs_sb_info
*sbi
,
765 unsigned long __user
*p
)
768 unsigned long ntimeout
;
770 if ((rv
= get_user(ntimeout
, p
)) ||
771 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
774 if (ntimeout
> ULONG_MAX
/HZ
)
775 sbi
->exp_timeout
= 0;
777 sbi
->exp_timeout
= ntimeout
* HZ
;
782 /* Return protocol version */
783 static inline int autofs4_get_protover(struct autofs_sb_info
*sbi
, int __user
*p
)
785 return put_user(sbi
->version
, p
);
788 /* Return protocol sub version */
789 static inline int autofs4_get_protosubver(struct autofs_sb_info
*sbi
, int __user
*p
)
791 return put_user(sbi
->sub_version
, p
);
795 * Tells the daemon whether it can umount the autofs mount.
797 static inline int autofs4_ask_umount(struct vfsmount
*mnt
, int __user
*p
)
804 DPRINTK("returning %d", status
);
806 status
= put_user(status
, p
);
811 /* Identify autofs4_dentries - this is so we can tell if there's
812 an extra dentry refcount or not. We only hold a refcount on the
813 dentry if its non-negative (ie, d_inode != NULL)
815 int is_autofs4_dentry(struct dentry
*dentry
)
817 return dentry
&& dentry
->d_inode
&&
818 dentry
->d_op
== &autofs4_dentry_operations
&&
819 dentry
->d_fsdata
!= NULL
;
823 * ioctl()'s on the root directory is the chief method for the daemon to
824 * generate kernel reactions
826 static int autofs4_root_ioctl_unlocked(struct inode
*inode
, struct file
*filp
,
827 unsigned int cmd
, unsigned long arg
)
829 struct autofs_sb_info
*sbi
= autofs4_sbi(inode
->i_sb
);
830 void __user
*p
= (void __user
*)arg
;
832 DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
833 cmd
,arg
,sbi
,task_pgrp_nr(current
));
835 if (_IOC_TYPE(cmd
) != _IOC_TYPE(AUTOFS_IOC_FIRST
) ||
836 _IOC_NR(cmd
) - _IOC_NR(AUTOFS_IOC_FIRST
) >= AUTOFS_IOC_COUNT
)
839 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
843 case AUTOFS_IOC_READY
: /* Wait queue: go ahead and retry */
844 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,0);
845 case AUTOFS_IOC_FAIL
: /* Wait queue: fail with ENOENT */
846 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,-ENOENT
);
847 case AUTOFS_IOC_CATATONIC
: /* Enter catatonic mode (daemon shutdown) */
848 autofs4_catatonic_mode(sbi
);
850 case AUTOFS_IOC_PROTOVER
: /* Get protocol version */
851 return autofs4_get_protover(sbi
, p
);
852 case AUTOFS_IOC_PROTOSUBVER
: /* Get protocol sub version */
853 return autofs4_get_protosubver(sbi
, p
);
854 case AUTOFS_IOC_SETTIMEOUT
:
855 return autofs4_get_set_timeout(sbi
, p
);
857 case AUTOFS_IOC_SETTIMEOUT32
:
858 return autofs4_compat_get_set_timeout(sbi
, p
);
861 case AUTOFS_IOC_ASKUMOUNT
:
862 return autofs4_ask_umount(filp
->f_path
.mnt
, p
);
864 /* return a single thing to expire */
865 case AUTOFS_IOC_EXPIRE
:
866 return autofs4_expire_run(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
867 /* same as above, but can send multiple expires through pipe */
868 case AUTOFS_IOC_EXPIRE_MULTI
:
869 return autofs4_expire_multi(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
876 static long autofs4_root_ioctl(struct file
*filp
,
877 unsigned int cmd
, unsigned long arg
)
879 struct inode
*inode
= file_inode(filp
);
880 return autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
884 static long autofs4_root_compat_ioctl(struct file
*filp
,
885 unsigned int cmd
, unsigned long arg
)
887 struct inode
*inode
= file_inode(filp
);
890 if (cmd
== AUTOFS_IOC_READY
|| cmd
== AUTOFS_IOC_FAIL
)
891 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
893 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
,
894 (unsigned long)compat_ptr(arg
));