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 DEFINE_SPINLOCK(autofs4_lock);
28 static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
29 static int autofs4_dir_unlink(struct inode *,struct dentry *);
30 static int autofs4_dir_rmdir(struct inode *,struct dentry *);
31 static int autofs4_dir_mkdir(struct inode *,struct dentry *,int);
32 static long autofs4_root_ioctl(struct file *,unsigned int,unsigned long);
34 static long autofs4_root_compat_ioctl(struct file *,unsigned int,unsigned long);
36 static int autofs4_dir_open(struct inode *inode, struct file *file);
37 static struct dentry *autofs4_lookup(struct inode *,struct dentry *, struct nameidata *);
38 static struct vfsmount *autofs4_d_automount(struct path *);
39 static int autofs4_d_manage(struct dentry *, bool, bool);
41 const struct file_operations autofs4_root_operations = {
42 .open = dcache_dir_open,
43 .release = dcache_dir_close,
44 .read = generic_read_dir,
45 .readdir = dcache_readdir,
46 .llseek = dcache_dir_lseek,
47 .unlocked_ioctl = autofs4_root_ioctl,
49 .compat_ioctl = autofs4_root_compat_ioctl,
53 const struct file_operations autofs4_dir_operations = {
54 .open = autofs4_dir_open,
55 .release = dcache_dir_close,
56 .read = generic_read_dir,
57 .readdir = dcache_readdir,
58 .llseek = dcache_dir_lseek,
61 const struct inode_operations autofs4_dir_inode_operations = {
62 .lookup = autofs4_lookup,
63 .unlink = autofs4_dir_unlink,
64 .symlink = autofs4_dir_symlink,
65 .mkdir = autofs4_dir_mkdir,
66 .rmdir = autofs4_dir_rmdir,
69 /* For dentries that don't initiate mounting */
70 const struct dentry_operations autofs4_dentry_operations = {
71 .d_release = autofs4_dentry_release,
74 /* For dentries that do initiate mounting */
75 const struct dentry_operations autofs4_mount_dentry_operations = {
76 .d_automount = autofs4_d_automount,
77 .d_manage = autofs4_d_manage,
78 .d_release = autofs4_dentry_release,
81 static void autofs4_add_active(struct dentry *dentry)
83 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
84 struct autofs_info *ino = autofs4_dentry_ino(dentry);
86 spin_lock(&sbi->lookup_lock);
87 if (!ino->active_count) {
88 if (list_empty(&ino->active))
89 list_add(&ino->active, &sbi->active_list);
92 spin_unlock(&sbi->lookup_lock);
97 static void autofs4_del_active(struct dentry *dentry)
99 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
100 struct autofs_info *ino = autofs4_dentry_ino(dentry);
102 spin_lock(&sbi->lookup_lock);
104 if (!ino->active_count) {
105 if (!list_empty(&ino->active))
106 list_del_init(&ino->active);
108 spin_unlock(&sbi->lookup_lock);
113 static int autofs4_dir_open(struct inode *inode, struct file *file)
115 struct dentry *dentry = file->f_path.dentry;
116 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
118 DPRINTK("file=%p dentry=%p %.*s",
119 file, dentry, dentry->d_name.len, dentry->d_name.name);
121 if (autofs4_oz_mode(sbi))
125 * An empty directory in an autofs file system is always a
126 * mount point. The daemon must have failed to mount this
127 * during lookup so it doesn't exist. This can happen, for
128 * example, if user space returns an incorrect status for a
129 * mount request. Otherwise we're doing a readdir on the
130 * autofs file system so just let the libfs routines handle
133 spin_lock(&autofs4_lock);
134 spin_lock(&dentry->d_lock);
135 if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
136 spin_unlock(&dentry->d_lock);
137 spin_unlock(&autofs4_lock);
140 spin_unlock(&dentry->d_lock);
141 spin_unlock(&autofs4_lock);
144 return dcache_dir_open(inode, file);
147 void autofs4_dentry_release(struct dentry *de)
149 struct autofs_info *inf;
151 DPRINTK("releasing %p", de);
153 inf = autofs4_dentry_ino(de);
155 struct autofs_sb_info *sbi = autofs4_sbi(de->d_sb);
157 spin_lock(&sbi->lookup_lock);
158 if (!list_empty(&inf->active))
159 list_del(&inf->active);
160 if (!list_empty(&inf->expiring))
161 list_del(&inf->expiring);
162 spin_unlock(&sbi->lookup_lock);
164 autofs4_free_ino(inf);
168 static struct dentry *autofs4_lookup_active(struct dentry *dentry)
170 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
171 struct dentry *parent = dentry->d_parent;
172 struct qstr *name = &dentry->d_name;
173 unsigned int len = name->len;
174 unsigned int hash = name->hash;
175 const unsigned char *str = name->name;
176 struct list_head *p, *head;
178 spin_lock(&autofs4_lock);
179 spin_lock(&sbi->lookup_lock);
180 head = &sbi->active_list;
181 list_for_each(p, head) {
182 struct autofs_info *ino;
183 struct dentry *active;
186 ino = list_entry(p, struct autofs_info, active);
187 active = ino->dentry;
189 spin_lock(&active->d_lock);
192 if (active->d_count == 0)
195 qstr = &active->d_name;
197 if (active->d_name.hash != hash)
199 if (active->d_parent != parent)
202 if (qstr->len != len)
204 if (memcmp(qstr->name, str, len))
207 if (d_unhashed(active)) {
209 spin_unlock(&active->d_lock);
210 spin_unlock(&sbi->lookup_lock);
211 spin_unlock(&autofs4_lock);
215 spin_unlock(&active->d_lock);
217 spin_unlock(&sbi->lookup_lock);
218 spin_unlock(&autofs4_lock);
223 static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
225 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
226 struct dentry *parent = dentry->d_parent;
227 struct qstr *name = &dentry->d_name;
228 unsigned int len = name->len;
229 unsigned int hash = name->hash;
230 const unsigned char *str = name->name;
231 struct list_head *p, *head;
233 spin_lock(&autofs4_lock);
234 spin_lock(&sbi->lookup_lock);
235 head = &sbi->expiring_list;
236 list_for_each(p, head) {
237 struct autofs_info *ino;
238 struct dentry *expiring;
241 ino = list_entry(p, struct autofs_info, expiring);
242 expiring = ino->dentry;
244 spin_lock(&expiring->d_lock);
246 /* Bad luck, we've already been dentry_iput */
247 if (!expiring->d_inode)
250 qstr = &expiring->d_name;
252 if (expiring->d_name.hash != hash)
254 if (expiring->d_parent != parent)
257 if (qstr->len != len)
259 if (memcmp(qstr->name, str, len))
262 if (d_unhashed(expiring)) {
263 dget_dlock(expiring);
264 spin_unlock(&expiring->d_lock);
265 spin_unlock(&sbi->lookup_lock);
266 spin_unlock(&autofs4_lock);
270 spin_unlock(&expiring->d_lock);
272 spin_unlock(&sbi->lookup_lock);
273 spin_unlock(&autofs4_lock);
278 static int autofs4_mount_wait(struct dentry *dentry)
280 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
281 struct autofs_info *ino = autofs4_dentry_ino(dentry);
284 if (ino->flags & AUTOFS_INF_PENDING) {
285 DPRINTK("waiting for mount name=%.*s",
286 dentry->d_name.len, dentry->d_name.name);
287 status = autofs4_wait(sbi, dentry, NFY_MOUNT);
288 DPRINTK("mount wait done status=%d", status);
289 ino->last_used = jiffies;
295 static int do_expire_wait(struct dentry *dentry)
297 struct dentry *expiring;
299 expiring = autofs4_lookup_expiring(dentry);
301 return autofs4_expire_wait(dentry);
304 * If we are racing with expire the request might not
305 * be quite complete, but the directory has been removed
306 * so it must have been successful, just wait for it.
308 autofs4_expire_wait(expiring);
309 autofs4_del_expiring(expiring);
315 static struct dentry *autofs4_mountpoint_changed(struct path *path)
317 struct dentry *dentry = path->dentry;
318 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
321 * If this is an indirect mount the dentry could have gone away
322 * as a result of an expire and a new one created.
324 if (autofs_type_indirect(sbi->type) && d_unhashed(dentry)) {
325 struct dentry *parent = dentry->d_parent;
326 struct dentry *new = d_lookup(parent, &dentry->d_name);
335 static struct vfsmount *autofs4_d_automount(struct path *path)
337 struct dentry *dentry = path->dentry;
338 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
339 struct autofs_info *ino = autofs4_dentry_ino(dentry);
342 DPRINTK("dentry=%p %.*s",
343 dentry, dentry->d_name.len, dentry->d_name.name);
346 * Someone may have manually umounted this or it was a submount
347 * that has gone away.
349 spin_lock(&dentry->d_lock);
350 if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
351 if (!(dentry->d_flags & DCACHE_MANAGE_TRANSIT) &&
352 (dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
353 __managed_dentry_set_transit(path->dentry);
355 spin_unlock(&dentry->d_lock);
357 /* The daemon never triggers a mount. */
358 if (autofs4_oz_mode(sbi))
362 * If an expire request is pending everyone must wait.
363 * If the expire fails we're still mounted so continue
364 * the follow and return. A return of -EAGAIN (which only
365 * happens with indirect mounts) means the expire completed
366 * and the directory was removed, so just go ahead and try
369 status = do_expire_wait(dentry);
370 if (status && status != -EAGAIN)
373 /* Callback to the daemon to perform the mount or wait */
374 spin_lock(&sbi->fs_lock);
375 if (ino->flags & AUTOFS_INF_PENDING) {
376 spin_unlock(&sbi->fs_lock);
377 status = autofs4_mount_wait(dentry);
379 return ERR_PTR(status);
380 spin_lock(&sbi->fs_lock);
385 * If the dentry is a symlink it's equivalent to a directory
386 * having d_mountpoint() true, so there's no need to call back
389 if (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode))
391 if (!d_mountpoint(dentry)) {
393 * It's possible that user space hasn't removed directories
394 * after umounting a rootless multi-mount, although it
395 * should. For v5 have_submounts() is sufficient to handle
396 * this because the leaves of the directory tree under the
397 * mount never trigger mounts themselves (they have an autofs
398 * trigger mount mounted on them). But v4 pseudo direct mounts
399 * do need the leaves to to trigger mounts. In this case we
400 * have no choice but to use the list_empty() check and
401 * require user space behave.
403 if (sbi->version > 4) {
404 if (have_submounts(dentry))
407 spin_lock(&dentry->d_lock);
408 if (!list_empty(&dentry->d_subdirs)) {
409 spin_unlock(&dentry->d_lock);
412 spin_unlock(&dentry->d_lock);
414 ino->flags |= AUTOFS_INF_PENDING;
415 spin_unlock(&sbi->fs_lock);
416 status = autofs4_mount_wait(dentry);
418 return ERR_PTR(status);
419 spin_lock(&sbi->fs_lock);
420 ino->flags &= ~AUTOFS_INF_PENDING;
423 if (!(ino->flags & AUTOFS_INF_EXPIRING)) {
425 * Any needed mounting has been completed and the path updated
426 * so turn this into a normal dentry so we don't continually
427 * call ->d_automount() and ->d_manage().
429 spin_lock(&dentry->d_lock);
430 __managed_dentry_clear_transit(dentry);
432 * Only clear DMANAGED_AUTOMOUNT for rootless multi-mounts and
433 * symlinks as in all other cases the dentry will be covered by
434 * an actual mount so ->d_automount() won't be called during
437 if ((!d_mountpoint(dentry) &&
438 !list_empty(&dentry->d_subdirs)) ||
439 (dentry->d_inode && S_ISLNK(dentry->d_inode->i_mode)))
440 __managed_dentry_clear_automount(dentry);
441 spin_unlock(&dentry->d_lock);
443 spin_unlock(&sbi->fs_lock);
445 /* Mount succeeded, check if we ended up with a new dentry */
446 dentry = autofs4_mountpoint_changed(path);
448 return ERR_PTR(-ENOENT);
453 int autofs4_d_manage(struct dentry *dentry, bool mounting_here, bool rcu_walk)
455 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
457 DPRINTK("dentry=%p %.*s",
458 dentry, dentry->d_name.len, dentry->d_name.name);
460 /* The daemon never waits. */
461 if (autofs4_oz_mode(sbi) || mounting_here) {
462 if (!d_mountpoint(dentry))
467 /* We need to sleep, so we need pathwalk to be in ref-mode */
471 /* Wait for pending expires */
472 do_expire_wait(dentry);
475 * This dentry may be under construction so wait on mount
478 return autofs4_mount_wait(dentry);
481 /* Lookups in the root directory */
482 static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
484 struct autofs_sb_info *sbi;
485 struct autofs_info *ino;
486 struct dentry *active;
488 DPRINTK("name = %.*s", dentry->d_name.len, dentry->d_name.name);
490 /* File name too long to exist */
491 if (dentry->d_name.len > NAME_MAX)
492 return ERR_PTR(-ENAMETOOLONG);
494 sbi = autofs4_sbi(dir->i_sb);
496 DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
497 current->pid, task_pgrp_nr(current), sbi->catatonic, oz_mode);
499 active = autofs4_lookup_active(dentry);
503 d_set_d_op(dentry, &autofs4_dentry_operations);
506 * A dentry that is not within the root can never trigger a
507 * mount operation, unless the directory already exists, so we
508 * can return fail immediately. The daemon however does need
509 * to create directories within the file system.
511 if (!autofs4_oz_mode(sbi) && !IS_ROOT(dentry->d_parent))
512 return ERR_PTR(-ENOENT);
514 /* Mark entries in the root as mount triggers */
515 if (autofs_type_indirect(sbi->type) && IS_ROOT(dentry->d_parent)) {
516 d_set_d_op(dentry, &autofs4_mount_dentry_operations);
517 __managed_dentry_set_managed(dentry);
520 ino = autofs4_init_ino(NULL, sbi, 0555);
522 return ERR_PTR(-ENOMEM);
524 dentry->d_fsdata = ino;
525 ino->dentry = dentry;
527 autofs4_add_active(dentry);
529 d_instantiate(dentry, NULL);
534 static int autofs4_dir_symlink(struct inode *dir,
535 struct dentry *dentry,
538 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
539 struct autofs_info *ino = autofs4_dentry_ino(dentry);
540 struct autofs_info *p_ino;
544 DPRINTK("%s <- %.*s", symname,
545 dentry->d_name.len, dentry->d_name.name);
547 if (!autofs4_oz_mode(sbi))
550 ino = autofs4_init_ino(ino, sbi, S_IFLNK | 0555);
554 autofs4_del_active(dentry);
556 ino->size = strlen(symname);
557 cp = kmalloc(ino->size + 1, GFP_KERNEL);
559 if (!dentry->d_fsdata)
566 inode = autofs4_get_inode(dir->i_sb, ino);
569 if (!dentry->d_fsdata)
573 d_add(dentry, inode);
575 d_set_d_op(dentry, &autofs4_dentry_operations);
577 dentry->d_fsdata = ino;
578 ino->dentry = dget(dentry);
579 atomic_inc(&ino->count);
580 p_ino = autofs4_dentry_ino(dentry->d_parent);
581 if (p_ino && dentry->d_parent != dentry)
582 atomic_inc(&p_ino->count);
585 dir->i_mtime = CURRENT_TIME;
593 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
594 * that the file no longer exists. However, doing that means that the
595 * VFS layer can turn the dentry into a negative dentry. We don't want
596 * this, because the unlink is probably the result of an expire.
597 * We simply d_drop it and add it to a expiring list in the super block,
598 * which allows the dentry lookup to check for an incomplete expire.
600 * If a process is blocked on the dentry waiting for the expire to finish,
601 * it will invalidate the dentry and try to mount with a new one.
603 * Also see autofs4_dir_rmdir()..
605 static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
607 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
608 struct autofs_info *ino = autofs4_dentry_ino(dentry);
609 struct autofs_info *p_ino;
611 /* This allows root to remove symlinks */
612 if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
615 if (atomic_dec_and_test(&ino->count)) {
616 p_ino = autofs4_dentry_ino(dentry->d_parent);
617 if (p_ino && dentry->d_parent != dentry)
618 atomic_dec(&p_ino->count);
622 dentry->d_inode->i_size = 0;
623 clear_nlink(dentry->d_inode);
625 dir->i_mtime = CURRENT_TIME;
627 spin_lock(&autofs4_lock);
628 autofs4_add_expiring(dentry);
629 spin_lock(&dentry->d_lock);
631 spin_unlock(&dentry->d_lock);
632 spin_unlock(&autofs4_lock);
638 * Version 4 of autofs provides a pseudo direct mount implementation
639 * that relies on directories at the leaves of a directory tree under
640 * an indirect mount to trigger mounts. To allow for this we need to
641 * set the DMANAGED_AUTOMOUNT and DMANAGED_TRANSIT flags on the leaves
642 * of the directory tree. There is no need to clear the automount flag
643 * following a mount or restore it after an expire because these mounts
644 * are always covered. However, it is neccessary to ensure that these
645 * flags are clear on non-empty directories to avoid unnecessary calls
648 static void autofs_set_leaf_automount_flags(struct dentry *dentry)
650 struct dentry *parent;
652 /* root and dentrys in the root are already handled */
653 if (IS_ROOT(dentry->d_parent))
656 managed_dentry_set_managed(dentry);
658 parent = dentry->d_parent;
659 /* only consider parents below dentrys in the root */
660 if (IS_ROOT(parent->d_parent))
662 managed_dentry_clear_managed(parent);
666 static void autofs_clear_leaf_automount_flags(struct dentry *dentry)
668 struct list_head *d_child;
669 struct dentry *parent;
671 /* flags for dentrys in the root are handled elsewhere */
672 if (IS_ROOT(dentry->d_parent))
675 managed_dentry_clear_managed(dentry);
677 parent = dentry->d_parent;
678 /* only consider parents below dentrys in the root */
679 if (IS_ROOT(parent->d_parent))
681 d_child = &dentry->d_u.d_child;
682 /* Set parent managed if it's becoming empty */
683 if (d_child->next == &parent->d_subdirs &&
684 d_child->prev == &parent->d_subdirs)
685 managed_dentry_set_managed(parent);
689 static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
691 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
692 struct autofs_info *ino = autofs4_dentry_ino(dentry);
693 struct autofs_info *p_ino;
695 DPRINTK("dentry %p, removing %.*s",
696 dentry, dentry->d_name.len, dentry->d_name.name);
698 if (!autofs4_oz_mode(sbi))
701 spin_lock(&autofs4_lock);
702 spin_lock(&sbi->lookup_lock);
703 spin_lock(&dentry->d_lock);
704 if (!list_empty(&dentry->d_subdirs)) {
705 spin_unlock(&dentry->d_lock);
706 spin_unlock(&sbi->lookup_lock);
707 spin_unlock(&autofs4_lock);
710 __autofs4_add_expiring(dentry);
711 spin_unlock(&sbi->lookup_lock);
713 spin_unlock(&dentry->d_lock);
714 spin_unlock(&autofs4_lock);
716 if (sbi->version < 5)
717 autofs_clear_leaf_automount_flags(dentry);
719 if (atomic_dec_and_test(&ino->count)) {
720 p_ino = autofs4_dentry_ino(dentry->d_parent);
721 if (p_ino && dentry->d_parent != dentry)
722 atomic_dec(&p_ino->count);
725 dentry->d_inode->i_size = 0;
726 clear_nlink(dentry->d_inode);
734 static int autofs4_dir_mkdir(struct inode *dir, struct dentry *dentry, int mode)
736 struct autofs_sb_info *sbi = autofs4_sbi(dir->i_sb);
737 struct autofs_info *ino = autofs4_dentry_ino(dentry);
738 struct autofs_info *p_ino;
741 if (!autofs4_oz_mode(sbi))
744 DPRINTK("dentry %p, creating %.*s",
745 dentry, dentry->d_name.len, dentry->d_name.name);
747 ino = autofs4_init_ino(ino, sbi, S_IFDIR | 0555);
751 autofs4_del_active(dentry);
753 inode = autofs4_get_inode(dir->i_sb, ino);
755 if (!dentry->d_fsdata)
759 d_add(dentry, inode);
761 if (sbi->version < 5)
762 autofs_set_leaf_automount_flags(dentry);
764 dentry->d_fsdata = ino;
765 ino->dentry = dget(dentry);
766 atomic_inc(&ino->count);
767 p_ino = autofs4_dentry_ino(dentry->d_parent);
768 if (p_ino && dentry->d_parent != dentry)
769 atomic_inc(&p_ino->count);
771 dir->i_mtime = CURRENT_TIME;
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)
782 unsigned long ntimeout;
784 if ((rv = get_user(ntimeout, p)) ||
785 (rv = put_user(sbi->exp_timeout/HZ, p)))
788 if (ntimeout > UINT_MAX/HZ)
789 sbi->exp_timeout = 0;
791 sbi->exp_timeout = ntimeout * HZ;
797 static inline int autofs4_get_set_timeout(struct autofs_sb_info *sbi,
798 unsigned long __user *p)
801 unsigned long ntimeout;
803 if ((rv = get_user(ntimeout, p)) ||
804 (rv = put_user(sbi->exp_timeout/HZ, p)))
807 if (ntimeout > ULONG_MAX/HZ)
808 sbi->exp_timeout = 0;
810 sbi->exp_timeout = ntimeout * HZ;
815 /* Return protocol version */
816 static inline int autofs4_get_protover(struct autofs_sb_info *sbi, int __user *p)
818 return put_user(sbi->version, p);
821 /* Return protocol sub version */
822 static inline int autofs4_get_protosubver(struct autofs_sb_info *sbi, int __user *p)
824 return put_user(sbi->sub_version, p);
828 * Tells the daemon whether it can umount the autofs mount.
830 static inline int autofs4_ask_umount(struct vfsmount *mnt, int __user *p)
837 DPRINTK("returning %d", status);
839 status = put_user(status, p);
844 /* Identify autofs4_dentries - this is so we can tell if there's
845 an extra dentry refcount or not. We only hold a refcount on the
846 dentry if its non-negative (ie, d_inode != NULL)
848 int is_autofs4_dentry(struct dentry *dentry)
850 return dentry && dentry->d_inode &&
851 (dentry->d_op == &autofs4_mount_dentry_operations ||
852 dentry->d_op == &autofs4_dentry_operations) &&
853 dentry->d_fsdata != NULL;
857 * ioctl()'s on the root directory is the chief method for the daemon to
858 * generate kernel reactions
860 static int autofs4_root_ioctl_unlocked(struct inode *inode, struct file *filp,
861 unsigned int cmd, unsigned long arg)
863 struct autofs_sb_info *sbi = autofs4_sbi(inode->i_sb);
864 void __user *p = (void __user *)arg;
866 DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
867 cmd,arg,sbi,task_pgrp_nr(current));
869 if (_IOC_TYPE(cmd) != _IOC_TYPE(AUTOFS_IOC_FIRST) ||
870 _IOC_NR(cmd) - _IOC_NR(AUTOFS_IOC_FIRST) >= AUTOFS_IOC_COUNT)
873 if (!autofs4_oz_mode(sbi) && !capable(CAP_SYS_ADMIN))
877 case AUTOFS_IOC_READY: /* Wait queue: go ahead and retry */
878 return autofs4_wait_release(sbi,(autofs_wqt_t)arg,0);
879 case AUTOFS_IOC_FAIL: /* Wait queue: fail with ENOENT */
880 return autofs4_wait_release(sbi,(autofs_wqt_t)arg,-ENOENT);
881 case AUTOFS_IOC_CATATONIC: /* Enter catatonic mode (daemon shutdown) */
882 autofs4_catatonic_mode(sbi);
884 case AUTOFS_IOC_PROTOVER: /* Get protocol version */
885 return autofs4_get_protover(sbi, p);
886 case AUTOFS_IOC_PROTOSUBVER: /* Get protocol sub version */
887 return autofs4_get_protosubver(sbi, p);
888 case AUTOFS_IOC_SETTIMEOUT:
889 return autofs4_get_set_timeout(sbi, p);
891 case AUTOFS_IOC_SETTIMEOUT32:
892 return autofs4_compat_get_set_timeout(sbi, p);
895 case AUTOFS_IOC_ASKUMOUNT:
896 return autofs4_ask_umount(filp->f_path.mnt, p);
898 /* return a single thing to expire */
899 case AUTOFS_IOC_EXPIRE:
900 return autofs4_expire_run(inode->i_sb,filp->f_path.mnt,sbi, p);
901 /* same as above, but can send multiple expires through pipe */
902 case AUTOFS_IOC_EXPIRE_MULTI:
903 return autofs4_expire_multi(inode->i_sb,filp->f_path.mnt,sbi, p);
910 static long autofs4_root_ioctl(struct file *filp,
911 unsigned int cmd, unsigned long arg)
913 struct inode *inode = filp->f_dentry->d_inode;
914 return autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
918 static long autofs4_root_compat_ioctl(struct file *filp,
919 unsigned int cmd, unsigned long arg)
921 struct inode *inode = filp->f_path.dentry->d_inode;
924 if (cmd == AUTOFS_IOC_READY || cmd == AUTOFS_IOC_FAIL)
925 ret = autofs4_root_ioctl_unlocked(inode, filp, cmd, arg);
927 ret = autofs4_root_ioctl_unlocked(inode, filp, cmd,
928 (unsigned long)compat_ptr(arg));