2 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
3 * Copyright 1999-2000 Jeremy Fitzhardinge <jeremy@goop.org>
4 * Copyright 2001-2006 Ian Kent <raven@themaw.net>
6 * This file is part of the Linux kernel and is made available under
7 * the terms of the GNU General Public License, version 2, or at your
8 * option, any later version, incorporated herein by reference.
11 #include <linux/capability.h>
12 #include <linux/errno.h>
13 #include <linux/stat.h>
14 #include <linux/slab.h>
15 #include <linux/param.h>
16 #include <linux/time.h>
17 #include <linux/compat.h>
18 #include <linux/mutex.h>
22 static int autofs4_dir_symlink(struct inode
*, struct dentry
*, const char *);
23 static int autofs4_dir_unlink(struct inode
*, struct dentry
*);
24 static int autofs4_dir_rmdir(struct inode
*, struct dentry
*);
25 static int autofs4_dir_mkdir(struct inode
*, struct dentry
*, umode_t
);
26 static long autofs4_root_ioctl(struct file
*, unsigned int, unsigned long);
28 static long autofs4_root_compat_ioctl(struct file
*,
29 unsigned int, unsigned long);
31 static int autofs4_dir_open(struct inode
*inode
, struct file
*file
);
32 static struct dentry
*autofs4_lookup(struct inode
*,
33 struct dentry
*, unsigned int);
34 static struct vfsmount
*autofs4_d_automount(struct path
*);
35 static int autofs4_d_manage(const struct path
*, bool);
36 static void autofs4_dentry_release(struct dentry
*);
38 const struct file_operations autofs4_root_operations
= {
39 .open
= dcache_dir_open
,
40 .release
= dcache_dir_close
,
41 .read
= generic_read_dir
,
42 .iterate_shared
= dcache_readdir
,
43 .llseek
= dcache_dir_lseek
,
44 .unlocked_ioctl
= autofs4_root_ioctl
,
46 .compat_ioctl
= autofs4_root_compat_ioctl
,
50 const struct file_operations autofs4_dir_operations
= {
51 .open
= autofs4_dir_open
,
52 .release
= dcache_dir_close
,
53 .read
= generic_read_dir
,
54 .iterate_shared
= dcache_readdir
,
55 .llseek
= dcache_dir_lseek
,
58 const struct inode_operations autofs4_dir_inode_operations
= {
59 .lookup
= autofs4_lookup
,
60 .unlink
= autofs4_dir_unlink
,
61 .symlink
= autofs4_dir_symlink
,
62 .mkdir
= autofs4_dir_mkdir
,
63 .rmdir
= autofs4_dir_rmdir
,
66 const struct dentry_operations autofs4_dentry_operations
= {
67 .d_automount
= autofs4_d_automount
,
68 .d_manage
= autofs4_d_manage
,
69 .d_release
= autofs4_dentry_release
,
72 static void autofs4_add_active(struct dentry
*dentry
)
74 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
75 struct autofs_info
*ino
;
77 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
);
89 static void autofs4_del_active(struct dentry
*dentry
)
91 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
92 struct autofs_info
*ino
;
94 ino
= autofs4_dentry_ino(dentry
);
96 spin_lock(&sbi
->lookup_lock
);
98 if (!ino
->active_count
) {
99 if (!list_empty(&ino
->active
))
100 list_del_init(&ino
->active
);
102 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 pr_debug("file=%p dentry=%p %pd\n", 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 (!path_is_mountpoint(&file
->f_path
) && 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 pr_debug("releasing %p\n", 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 const 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
;
175 const struct qstr
*qstr
;
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 const 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
;
230 const struct qstr
*qstr
;
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(const struct path
*path
, bool rcu_walk
)
274 struct autofs_sb_info
*sbi
= autofs4_sbi(path
->dentry
->d_sb
);
275 struct autofs_info
*ino
= autofs4_dentry_ino(path
->dentry
);
278 if (ino
->flags
& AUTOFS_INF_PENDING
) {
281 pr_debug("waiting for mount name=%pd\n", path
->dentry
);
282 status
= autofs4_wait(sbi
, path
, NFY_MOUNT
);
283 pr_debug("mount wait done status=%d\n", status
);
284 ino
->last_used
= jiffies
;
289 static int do_expire_wait(const struct path
*path
, bool rcu_walk
)
291 struct dentry
*dentry
= path
->dentry
;
292 struct dentry
*expiring
;
294 expiring
= autofs4_lookup_expiring(dentry
, rcu_walk
);
295 if (IS_ERR(expiring
))
296 return PTR_ERR(expiring
);
298 return autofs4_expire_wait(path
, rcu_walk
);
300 const struct path
this = { .mnt
= path
->mnt
, .dentry
= expiring
};
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(&this, 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
;
326 new = d_lookup(parent
, &dentry
->d_name
);
332 struct autofs_info
*ino
;
334 ino
= autofs4_dentry_ino(new);
335 ino
->last_used
= jiffies
;
343 static struct vfsmount
*autofs4_d_automount(struct path
*path
)
345 struct dentry
*dentry
= path
->dentry
;
346 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
347 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
350 pr_debug("dentry=%p %pd\n", dentry
, dentry
);
352 /* The daemon never triggers a mount. */
353 if (autofs4_oz_mode(sbi
))
357 * If an expire request is pending everyone must wait.
358 * If the expire fails we're still mounted so continue
359 * the follow and return. A return of -EAGAIN (which only
360 * happens with indirect mounts) means the expire completed
361 * and the directory was removed, so just go ahead and try
364 status
= do_expire_wait(path
, 0);
365 if (status
&& status
!= -EAGAIN
)
368 /* Callback to the daemon to perform the mount or wait */
369 spin_lock(&sbi
->fs_lock
);
370 if (ino
->flags
& AUTOFS_INF_PENDING
) {
371 spin_unlock(&sbi
->fs_lock
);
372 status
= autofs4_mount_wait(path
, 0);
374 return ERR_PTR(status
);
379 * If the dentry is a symlink it's equivalent to a directory
380 * having path_is_mountpoint() true, so there's no need to call
381 * back to the daemon.
383 if (d_really_is_positive(dentry
) && d_is_symlink(dentry
)) {
384 spin_unlock(&sbi
->fs_lock
);
388 if (!path_is_mountpoint(path
)) {
390 * It's possible that user space hasn't removed directories
391 * after umounting a rootless multi-mount, although it
392 * should. For v5 path_has_submounts() is sufficient to
393 * handle this because the leaves of the directory tree under
394 * the mount never trigger mounts themselves (they have an
395 * autofs trigger mount mounted on them). But v4 pseudo direct
396 * mounts do need the leaves to trigger mounts. In this case
397 * we have no choice but to use the list_empty() check and
398 * require user space behave.
400 if (sbi
->version
> 4) {
401 if (path_has_submounts(path
)) {
402 spin_unlock(&sbi
->fs_lock
);
406 if (!simple_empty(dentry
)) {
407 spin_unlock(&sbi
->fs_lock
);
411 ino
->flags
|= AUTOFS_INF_PENDING
;
412 spin_unlock(&sbi
->fs_lock
);
413 status
= autofs4_mount_wait(path
, 0);
414 spin_lock(&sbi
->fs_lock
);
415 ino
->flags
&= ~AUTOFS_INF_PENDING
;
417 spin_unlock(&sbi
->fs_lock
);
418 return ERR_PTR(status
);
421 spin_unlock(&sbi
->fs_lock
);
423 /* Mount succeeded, check if we ended up with a new dentry */
424 dentry
= autofs4_mountpoint_changed(path
);
426 return ERR_PTR(-ENOENT
);
431 static int autofs4_d_manage(const struct path
*path
, bool rcu_walk
)
433 struct dentry
*dentry
= path
->dentry
;
434 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
435 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
438 pr_debug("dentry=%p %pd\n", dentry
, dentry
);
440 /* The daemon never waits. */
441 if (autofs4_oz_mode(sbi
)) {
442 if (!path_is_mountpoint(path
))
447 /* Wait for pending expires */
448 if (do_expire_wait(path
, rcu_walk
) == -ECHILD
)
452 * This dentry may be under construction so wait on mount
455 status
= autofs4_mount_wait(path
, rcu_walk
);
460 /* We don't need fs_lock in rcu_walk mode,
461 * just testing 'AUTOFS_INFO_NO_RCU' is enough.
462 * simple_empty() takes a spinlock, so leave it
464 * We only return -EISDIR when certain this isn't
469 if (ino
->flags
& AUTOFS_INF_WANT_EXPIRE
)
471 if (path_is_mountpoint(path
))
473 inode
= d_inode_rcu(dentry
);
474 if (inode
&& S_ISLNK(inode
->i_mode
))
476 if (list_empty(&dentry
->d_subdirs
))
478 if (!simple_empty(dentry
))
483 spin_lock(&sbi
->fs_lock
);
485 * If the dentry has been selected for expire while we slept
486 * on the lock then it might go away. We'll deal with that in
487 * ->d_automount() and wait on a new mount if the expire
488 * succeeds or return here if it doesn't (since there's no
489 * mount to follow with a rootless multi-mount).
491 if (!(ino
->flags
& AUTOFS_INF_EXPIRING
)) {
493 * Any needed mounting has been completed and the path
494 * updated so check if this is a rootless multi-mount so
495 * we can avoid needless calls ->d_automount() and avoid
496 * an incorrect ELOOP error return.
498 if ((!path_is_mountpoint(path
) && !simple_empty(dentry
)) ||
499 (d_really_is_positive(dentry
) && d_is_symlink(dentry
)))
502 spin_unlock(&sbi
->fs_lock
);
507 /* Lookups in the root directory */
508 static struct dentry
*autofs4_lookup(struct inode
*dir
,
509 struct dentry
*dentry
, unsigned int flags
)
511 struct autofs_sb_info
*sbi
;
512 struct autofs_info
*ino
;
513 struct dentry
*active
;
515 pr_debug("name = %pd\n", dentry
);
517 /* File name too long to exist */
518 if (dentry
->d_name
.len
> NAME_MAX
)
519 return ERR_PTR(-ENAMETOOLONG
);
521 sbi
= autofs4_sbi(dir
->i_sb
);
523 pr_debug("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d\n",
524 current
->pid
, task_pgrp_nr(current
), sbi
->catatonic
,
525 autofs4_oz_mode(sbi
));
527 active
= autofs4_lookup_active(dentry
);
532 * A dentry that is not within the root can never trigger a
533 * mount operation, unless the directory already exists, so we
534 * can return fail immediately. The daemon however does need
535 * to create directories within the file system.
537 if (!autofs4_oz_mode(sbi
) && !IS_ROOT(dentry
->d_parent
))
538 return ERR_PTR(-ENOENT
);
540 /* Mark entries in the root as mount triggers */
541 if (IS_ROOT(dentry
->d_parent
) &&
542 autofs_type_indirect(sbi
->type
))
543 __managed_dentry_set_managed(dentry
);
545 ino
= autofs4_new_ino(sbi
);
547 return ERR_PTR(-ENOMEM
);
549 dentry
->d_fsdata
= ino
;
550 ino
->dentry
= dentry
;
552 autofs4_add_active(dentry
);
557 static int autofs4_dir_symlink(struct inode
*dir
,
558 struct dentry
*dentry
,
561 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
562 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
563 struct autofs_info
*p_ino
;
565 size_t size
= strlen(symname
);
568 pr_debug("%s <- %pd\n", symname
, dentry
);
570 if (!autofs4_oz_mode(sbi
))
575 autofs4_clean_ino(ino
);
577 autofs4_del_active(dentry
);
579 cp
= kmalloc(size
+ 1, GFP_KERNEL
);
585 inode
= autofs4_get_inode(dir
->i_sb
, S_IFLNK
| 0555);
590 inode
->i_private
= cp
;
591 inode
->i_size
= size
;
592 d_add(dentry
, inode
);
595 atomic_inc(&ino
->count
);
596 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
597 if (p_ino
&& !IS_ROOT(dentry
))
598 atomic_inc(&p_ino
->count
);
600 dir
->i_mtime
= current_time(dir
);
608 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
609 * that the file no longer exists. However, doing that means that the
610 * VFS layer can turn the dentry into a negative dentry. We don't want
611 * this, because the unlink is probably the result of an expire.
612 * We simply d_drop it and add it to a expiring list in the super block,
613 * which allows the dentry lookup to check for an incomplete expire.
615 * If a process is blocked on the dentry waiting for the expire to finish,
616 * it will invalidate the dentry and try to mount with a new one.
618 * Also see autofs4_dir_rmdir()..
620 static int autofs4_dir_unlink(struct inode
*dir
, struct dentry
*dentry
)
622 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
623 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
624 struct autofs_info
*p_ino
;
626 /* This allows root to remove symlinks */
627 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
630 if (atomic_dec_and_test(&ino
->count
)) {
631 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
632 if (p_ino
&& !IS_ROOT(dentry
))
633 atomic_dec(&p_ino
->count
);
637 d_inode(dentry
)->i_size
= 0;
638 clear_nlink(d_inode(dentry
));
640 dir
->i_mtime
= current_time(dir
);
642 spin_lock(&sbi
->lookup_lock
);
643 __autofs4_add_expiring(dentry
);
645 spin_unlock(&sbi
->lookup_lock
);
651 * Version 4 of autofs provides a pseudo direct mount implementation
652 * that relies on directories at the leaves of a directory tree under
653 * an indirect mount to trigger mounts. To allow for this we need to
654 * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
655 * of the directory tree. There is no need to clear the automount flag
656 * following a mount or restore it after an expire because these mounts
657 * are always covered. However, it is necessary to ensure that these
658 * flags are clear on non-empty directories to avoid unnecessary calls
661 static void autofs_set_leaf_automount_flags(struct dentry
*dentry
)
663 struct dentry
*parent
;
665 /* root and dentrys in the root are already handled */
666 if (IS_ROOT(dentry
->d_parent
))
669 managed_dentry_set_managed(dentry
);
671 parent
= dentry
->d_parent
;
672 /* only consider parents below dentrys in the root */
673 if (IS_ROOT(parent
->d_parent
))
675 managed_dentry_clear_managed(parent
);
678 static void autofs_clear_leaf_automount_flags(struct dentry
*dentry
)
680 struct list_head
*d_child
;
681 struct dentry
*parent
;
683 /* flags for dentrys in the root are handled elsewhere */
684 if (IS_ROOT(dentry
->d_parent
))
687 managed_dentry_clear_managed(dentry
);
689 parent
= dentry
->d_parent
;
690 /* only consider parents below dentrys in the root */
691 if (IS_ROOT(parent
->d_parent
))
693 d_child
= &dentry
->d_child
;
694 /* Set parent managed if it's becoming empty */
695 if (d_child
->next
== &parent
->d_subdirs
&&
696 d_child
->prev
== &parent
->d_subdirs
)
697 managed_dentry_set_managed(parent
);
700 static int autofs4_dir_rmdir(struct inode
*dir
, struct dentry
*dentry
)
702 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
703 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
704 struct autofs_info
*p_ino
;
706 pr_debug("dentry %p, removing %pd\n", dentry
, dentry
);
708 if (!autofs4_oz_mode(sbi
))
711 spin_lock(&sbi
->lookup_lock
);
712 if (!simple_empty(dentry
)) {
713 spin_unlock(&sbi
->lookup_lock
);
716 __autofs4_add_expiring(dentry
);
718 spin_unlock(&sbi
->lookup_lock
);
720 if (sbi
->version
< 5)
721 autofs_clear_leaf_automount_flags(dentry
);
723 if (atomic_dec_and_test(&ino
->count
)) {
724 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
725 if (p_ino
&& dentry
->d_parent
!= dentry
)
726 atomic_dec(&p_ino
->count
);
729 d_inode(dentry
)->i_size
= 0;
730 clear_nlink(d_inode(dentry
));
738 static int autofs4_dir_mkdir(struct inode
*dir
,
739 struct dentry
*dentry
, umode_t mode
)
741 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
742 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
743 struct autofs_info
*p_ino
;
746 if (!autofs4_oz_mode(sbi
))
749 pr_debug("dentry %p, creating %pd\n", dentry
, dentry
);
753 autofs4_clean_ino(ino
);
755 autofs4_del_active(dentry
);
757 inode
= autofs4_get_inode(dir
->i_sb
, S_IFDIR
| 0555);
760 d_add(dentry
, inode
);
762 if (sbi
->version
< 5)
763 autofs_set_leaf_automount_flags(dentry
);
766 atomic_inc(&ino
->count
);
767 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
768 if (p_ino
&& !IS_ROOT(dentry
))
769 atomic_inc(&p_ino
->count
);
771 dir
->i_mtime
= current_time(dir
);
776 /* Get/set timeout ioctl() operation */
778 static inline int autofs4_compat_get_set_timeout(struct autofs_sb_info
*sbi
,
779 compat_ulong_t __user
*p
)
781 unsigned long ntimeout
;
784 rv
= get_user(ntimeout
, p
);
788 rv
= put_user(sbi
->exp_timeout
/HZ
, p
);
792 if (ntimeout
> UINT_MAX
/HZ
)
793 sbi
->exp_timeout
= 0;
795 sbi
->exp_timeout
= ntimeout
* HZ
;
803 static inline int autofs4_get_set_timeout(struct autofs_sb_info
*sbi
,
804 unsigned long __user
*p
)
806 unsigned long ntimeout
;
809 rv
= get_user(ntimeout
, p
);
813 rv
= put_user(sbi
->exp_timeout
/HZ
, p
);
817 if (ntimeout
> ULONG_MAX
/HZ
)
818 sbi
->exp_timeout
= 0;
820 sbi
->exp_timeout
= ntimeout
* HZ
;
827 /* Return protocol version */
828 static inline int autofs4_get_protover(struct autofs_sb_info
*sbi
,
831 return put_user(sbi
->version
, p
);
834 /* Return protocol sub version */
835 static inline int autofs4_get_protosubver(struct autofs_sb_info
*sbi
,
838 return put_user(sbi
->sub_version
, p
);
842 * Tells the daemon whether it can umount the autofs mount.
844 static inline int autofs4_ask_umount(struct vfsmount
*mnt
, int __user
*p
)
851 pr_debug("may umount %d\n", status
);
853 status
= put_user(status
, p
);
858 /* Identify autofs4_dentries - this is so we can tell if there's
859 * an extra dentry refcount or not. We only hold a refcount on the
860 * dentry if its non-negative (ie, d_inode != NULL)
862 int is_autofs4_dentry(struct dentry
*dentry
)
864 return dentry
&& d_really_is_positive(dentry
) &&
865 dentry
->d_op
== &autofs4_dentry_operations
&&
866 dentry
->d_fsdata
!= NULL
;
870 * ioctl()'s on the root directory is the chief method for the daemon to
871 * generate kernel reactions
873 static int autofs4_root_ioctl_unlocked(struct inode
*inode
, struct file
*filp
,
874 unsigned int cmd
, unsigned long arg
)
876 struct autofs_sb_info
*sbi
= autofs4_sbi(inode
->i_sb
);
877 void __user
*p
= (void __user
*)arg
;
879 pr_debug("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u\n",
880 cmd
, arg
, sbi
, task_pgrp_nr(current
));
882 if (_IOC_TYPE(cmd
) != _IOC_TYPE(AUTOFS_IOC_FIRST
) ||
883 _IOC_NR(cmd
) - _IOC_NR(AUTOFS_IOC_FIRST
) >= AUTOFS_IOC_COUNT
)
886 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
890 case AUTOFS_IOC_READY
: /* Wait queue: go ahead and retry */
891 return autofs4_wait_release(sbi
, (autofs_wqt_t
) arg
, 0);
892 case AUTOFS_IOC_FAIL
: /* Wait queue: fail with ENOENT */
893 return autofs4_wait_release(sbi
, (autofs_wqt_t
) arg
, -ENOENT
);
894 case AUTOFS_IOC_CATATONIC
: /* Enter catatonic mode (daemon shutdown) */
895 autofs4_catatonic_mode(sbi
);
897 case AUTOFS_IOC_PROTOVER
: /* Get protocol version */
898 return autofs4_get_protover(sbi
, p
);
899 case AUTOFS_IOC_PROTOSUBVER
: /* Get protocol sub version */
900 return autofs4_get_protosubver(sbi
, p
);
901 case AUTOFS_IOC_SETTIMEOUT
:
902 return autofs4_get_set_timeout(sbi
, p
);
904 case AUTOFS_IOC_SETTIMEOUT32
:
905 return autofs4_compat_get_set_timeout(sbi
, p
);
908 case AUTOFS_IOC_ASKUMOUNT
:
909 return autofs4_ask_umount(filp
->f_path
.mnt
, p
);
911 /* return a single thing to expire */
912 case AUTOFS_IOC_EXPIRE
:
913 return autofs4_expire_run(inode
->i_sb
,
914 filp
->f_path
.mnt
, sbi
, p
);
915 /* same as above, but can send multiple expires through pipe */
916 case AUTOFS_IOC_EXPIRE_MULTI
:
917 return autofs4_expire_multi(inode
->i_sb
,
918 filp
->f_path
.mnt
, sbi
, p
);
925 static long autofs4_root_ioctl(struct file
*filp
,
926 unsigned int cmd
, unsigned long arg
)
928 struct inode
*inode
= file_inode(filp
);
930 return autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
934 static long autofs4_root_compat_ioctl(struct file
*filp
,
935 unsigned int cmd
, unsigned long arg
)
937 struct inode
*inode
= file_inode(filp
);
940 if (cmd
== AUTOFS_IOC_READY
|| cmd
== AUTOFS_IOC_FAIL
)
941 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
, arg
);
943 ret
= autofs4_root_ioctl_unlocked(inode
, filp
, cmd
,
944 (unsigned long) compat_ptr(arg
));