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/param.h>
19 #include <linux/time.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
*,int);
26 static int autofs4_root_ioctl(struct inode
*, struct file
*,unsigned int,unsigned long);
27 static int autofs4_dir_open(struct inode
*inode
, struct file
*file
);
28 static int autofs4_root_readdir(struct file
* filp
, void * dirent
, filldir_t filldir
);
29 static struct dentry
*autofs4_lookup(struct inode
*,struct dentry
*, struct nameidata
*);
30 static void *autofs4_follow_link(struct dentry
*, struct nameidata
*);
32 #define TRIGGER_FLAGS (LOOKUP_CONTINUE | LOOKUP_DIRECTORY)
33 #define TRIGGER_INTENTS (LOOKUP_OPEN | LOOKUP_CREATE)
35 const struct file_operations autofs4_root_operations
= {
36 .open
= dcache_dir_open
,
37 .release
= dcache_dir_close
,
38 .read
= generic_read_dir
,
39 .readdir
= autofs4_root_readdir
,
40 .ioctl
= autofs4_root_ioctl
,
43 const struct file_operations autofs4_dir_operations
= {
44 .open
= autofs4_dir_open
,
45 .release
= dcache_dir_close
,
46 .read
= generic_read_dir
,
47 .readdir
= dcache_readdir
,
50 const struct inode_operations autofs4_indirect_root_inode_operations
= {
51 .lookup
= autofs4_lookup
,
52 .unlink
= autofs4_dir_unlink
,
53 .symlink
= autofs4_dir_symlink
,
54 .mkdir
= autofs4_dir_mkdir
,
55 .rmdir
= autofs4_dir_rmdir
,
58 const struct inode_operations autofs4_direct_root_inode_operations
= {
59 .lookup
= autofs4_lookup
,
60 .unlink
= autofs4_dir_unlink
,
61 .mkdir
= autofs4_dir_mkdir
,
62 .rmdir
= autofs4_dir_rmdir
,
63 .follow_link
= autofs4_follow_link
,
66 const struct inode_operations autofs4_dir_inode_operations
= {
67 .lookup
= autofs4_lookup
,
68 .unlink
= autofs4_dir_unlink
,
69 .symlink
= autofs4_dir_symlink
,
70 .mkdir
= autofs4_dir_mkdir
,
71 .rmdir
= autofs4_dir_rmdir
,
74 static int autofs4_root_readdir(struct file
*file
, void *dirent
,
77 struct autofs_sb_info
*sbi
= autofs4_sbi(file
->f_path
.dentry
->d_sb
);
78 int oz_mode
= autofs4_oz_mode(sbi
);
80 DPRINTK("called, filp->f_pos = %lld", file
->f_pos
);
83 * Don't set reghost flag if:
84 * 1) f_pos is larger than zero -- we've already been here.
85 * 2) we haven't even enabled reghosting in the 1st place.
86 * 3) this is the daemon doing a readdir
88 if (oz_mode
&& file
->f_pos
== 0 && sbi
->reghost_enabled
)
89 sbi
->needs_reghost
= 1;
91 DPRINTK("needs_reghost = %d", sbi
->needs_reghost
);
93 return dcache_readdir(file
, dirent
, filldir
);
96 static int autofs4_dir_open(struct inode
*inode
, struct file
*file
)
98 struct dentry
*dentry
= file
->f_path
.dentry
;
99 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
101 DPRINTK("file=%p dentry=%p %.*s",
102 file
, dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
104 if (autofs4_oz_mode(sbi
))
108 * An empty directory in an autofs file system is always a
109 * mount point. The daemon must have failed to mount this
110 * during lookup so it doesn't exist. This can happen, for
111 * example, if user space returns an incorrect status for a
112 * mount request. Otherwise we're doing a readdir on the
113 * autofs file system so just let the libfs routines handle
116 spin_lock(&dcache_lock
);
117 if (!d_mountpoint(dentry
) && __simple_empty(dentry
)) {
118 spin_unlock(&dcache_lock
);
121 spin_unlock(&dcache_lock
);
124 return dcache_dir_open(inode
, file
);
127 static int try_to_fill_dentry(struct dentry
*dentry
, int flags
)
129 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
130 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
133 /* Block on any pending expiry here; invalidate the dentry
134 when expiration is done to trigger mount request with a new
136 spin_lock(&sbi
->fs_lock
);
137 if (ino
->flags
& AUTOFS_INF_EXPIRING
) {
138 spin_unlock(&sbi
->fs_lock
);
140 DPRINTK("waiting for expire %p name=%.*s",
141 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
143 status
= autofs4_wait(sbi
, dentry
, NFY_NONE
);
145 DPRINTK("expire done status=%d", status
);
148 * If the directory still exists the mount request must
149 * continue otherwise it can't be followed at the right
150 * time during the walk.
152 status
= d_invalidate(dentry
);
153 if (status
!= -EBUSY
)
158 spin_unlock(&sbi
->fs_lock
);
160 DPRINTK("dentry=%p %.*s ino=%p",
161 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
, dentry
->d_inode
);
164 * Wait for a pending mount, triggering one if there
167 if (dentry
->d_inode
== NULL
) {
168 DPRINTK("waiting for mount name=%.*s",
169 dentry
->d_name
.len
, dentry
->d_name
.name
);
171 status
= autofs4_wait(sbi
, dentry
, NFY_MOUNT
);
173 DPRINTK("mount done status=%d", status
);
175 /* Turn this into a real negative dentry? */
176 if (status
== -ENOENT
) {
177 spin_lock(&dentry
->d_lock
);
178 dentry
->d_flags
&= ~DCACHE_AUTOFS_PENDING
;
179 spin_unlock(&dentry
->d_lock
);
182 /* Return a negative dentry, but leave it "pending" */
185 /* Trigger mount for path component or follow link */
186 } else if (dentry
->d_flags
& DCACHE_AUTOFS_PENDING
||
187 flags
& (TRIGGER_FLAGS
| TRIGGER_INTENTS
) ||
188 current
->link_count
) {
189 DPRINTK("waiting for mount name=%.*s",
190 dentry
->d_name
.len
, dentry
->d_name
.name
);
192 spin_lock(&dentry
->d_lock
);
193 dentry
->d_flags
|= DCACHE_AUTOFS_PENDING
;
194 spin_unlock(&dentry
->d_lock
);
195 status
= autofs4_wait(sbi
, dentry
, NFY_MOUNT
);
197 DPRINTK("mount done status=%d", status
);
200 spin_lock(&dentry
->d_lock
);
201 dentry
->d_flags
&= ~DCACHE_AUTOFS_PENDING
;
202 spin_unlock(&dentry
->d_lock
);
207 /* Initialize expiry counter after successful mount */
209 ino
->last_used
= jiffies
;
211 spin_lock(&dentry
->d_lock
);
212 dentry
->d_flags
&= ~DCACHE_AUTOFS_PENDING
;
213 spin_unlock(&dentry
->d_lock
);
218 /* For autofs direct mounts the follow link triggers the mount */
219 static void *autofs4_follow_link(struct dentry
*dentry
, struct nameidata
*nd
)
221 struct autofs_sb_info
*sbi
= autofs4_sbi(dentry
->d_sb
);
222 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
223 int oz_mode
= autofs4_oz_mode(sbi
);
224 unsigned int lookup_type
;
227 DPRINTK("dentry=%p %.*s oz_mode=%d nd->flags=%d",
228 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
, oz_mode
,
231 /* If it's our master or we shouldn't trigger a mount we're done */
232 lookup_type
= nd
->flags
& (TRIGGER_FLAGS
| TRIGGER_INTENTS
);
234 !(lookup_type
|| dentry
->d_flags
& DCACHE_AUTOFS_PENDING
))
237 /* If an expire request is pending wait for it. */
238 spin_lock(&sbi
->fs_lock
);
239 if (ino
->flags
& AUTOFS_INF_EXPIRING
) {
240 spin_unlock(&sbi
->fs_lock
);
242 DPRINTK("waiting for active request %p name=%.*s",
243 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
245 status
= autofs4_wait(sbi
, dentry
, NFY_NONE
);
247 DPRINTK("request done status=%d", status
);
251 spin_unlock(&sbi
->fs_lock
);
254 * If the dentry contains directories then it is an
255 * autofs multi-mount with no root mount offset. So
256 * don't try to mount it again.
258 spin_lock(&dcache_lock
);
259 if (dentry
->d_flags
& DCACHE_AUTOFS_PENDING
||
260 (!d_mountpoint(dentry
) && __simple_empty(dentry
))) {
261 spin_unlock(&dcache_lock
);
263 status
= try_to_fill_dentry(dentry
, 0);
268 * The mount succeeded but if there is no root mount
269 * it must be an autofs multi-mount with no root offset
270 * so we don't need to follow the mount.
272 if (d_mountpoint(dentry
)) {
273 if (!autofs4_follow_mount(&nd
->path
.mnt
,
282 spin_unlock(&dcache_lock
);
289 return ERR_PTR(status
);
293 * Revalidate is called on every cache lookup. Some of those
294 * cache lookups may actually happen while the dentry is not
295 * yet completely filled in, and revalidate has to delay such
298 static int autofs4_revalidate(struct dentry
*dentry
, struct nameidata
*nd
)
300 struct inode
*dir
= dentry
->d_parent
->d_inode
;
301 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
302 int oz_mode
= autofs4_oz_mode(sbi
);
303 int flags
= nd
? nd
->flags
: 0;
307 spin_lock(&sbi
->fs_lock
);
308 if (autofs4_ispending(dentry
)) {
309 /* The daemon never causes a mount to trigger */
310 spin_unlock(&sbi
->fs_lock
);
316 * A zero status is success otherwise we have a
317 * negative error code.
319 status
= try_to_fill_dentry(dentry
, flags
);
324 * A status of EAGAIN here means that the dentry has gone
325 * away while waiting for an expire to complete. If we are
326 * racing with expire lookup will wait for it so this must
327 * be a revalidate and we need to send it to lookup.
329 if (status
== -EAGAIN
)
334 spin_unlock(&sbi
->fs_lock
);
336 /* Negative dentry.. invalidate if "old" */
337 if (dentry
->d_inode
== NULL
)
340 /* Check for a non-mountpoint directory with no contents */
341 spin_lock(&dcache_lock
);
342 if (S_ISDIR(dentry
->d_inode
->i_mode
) &&
343 !d_mountpoint(dentry
) &&
344 __simple_empty(dentry
)) {
345 DPRINTK("dentry=%p %.*s, emptydir",
346 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
347 spin_unlock(&dcache_lock
);
349 /* The daemon never causes a mount to trigger */
354 * A zero status is success otherwise we have a
355 * negative error code.
357 status
= try_to_fill_dentry(dentry
, flags
);
363 spin_unlock(&dcache_lock
);
368 void autofs4_dentry_release(struct dentry
*de
)
370 struct autofs_info
*inf
;
372 DPRINTK("releasing %p", de
);
374 inf
= autofs4_dentry_ino(de
);
378 struct autofs_sb_info
*sbi
= autofs4_sbi(de
->d_sb
);
381 spin_lock(&sbi
->lookup_lock
);
382 if (!list_empty(&inf
->active
))
383 list_del(&inf
->active
);
384 if (!list_empty(&inf
->expiring
))
385 list_del(&inf
->expiring
);
386 spin_unlock(&sbi
->lookup_lock
);
392 autofs4_free_ino(inf
);
396 /* For dentries of directories in the root dir */
397 static struct dentry_operations autofs4_root_dentry_operations
= {
398 .d_revalidate
= autofs4_revalidate
,
399 .d_release
= autofs4_dentry_release
,
402 /* For other dentries */
403 static struct dentry_operations autofs4_dentry_operations
= {
404 .d_revalidate
= autofs4_revalidate
,
405 .d_release
= autofs4_dentry_release
,
408 static struct dentry
*autofs4_lookup_active(struct autofs_sb_info
*sbi
, struct dentry
*parent
, struct qstr
*name
)
410 unsigned int len
= name
->len
;
411 unsigned int hash
= name
->hash
;
412 const unsigned char *str
= name
->name
;
413 struct list_head
*p
, *head
;
415 spin_lock(&dcache_lock
);
416 spin_lock(&sbi
->lookup_lock
);
417 head
= &sbi
->active_list
;
418 list_for_each(p
, head
) {
419 struct autofs_info
*ino
;
420 struct dentry
*dentry
;
423 ino
= list_entry(p
, struct autofs_info
, active
);
424 dentry
= ino
->dentry
;
426 spin_lock(&dentry
->d_lock
);
429 if (atomic_read(&dentry
->d_count
) == 0)
432 qstr
= &dentry
->d_name
;
434 if (dentry
->d_name
.hash
!= hash
)
436 if (dentry
->d_parent
!= parent
)
439 if (qstr
->len
!= len
)
441 if (memcmp(qstr
->name
, str
, len
))
444 if (d_unhashed(dentry
)) {
446 spin_unlock(&dentry
->d_lock
);
447 spin_unlock(&sbi
->lookup_lock
);
448 spin_unlock(&dcache_lock
);
452 spin_unlock(&dentry
->d_lock
);
454 spin_unlock(&sbi
->lookup_lock
);
455 spin_unlock(&dcache_lock
);
460 static struct dentry
*autofs4_lookup_expiring(struct autofs_sb_info
*sbi
, struct dentry
*parent
, struct qstr
*name
)
462 unsigned int len
= name
->len
;
463 unsigned int hash
= name
->hash
;
464 const unsigned char *str
= name
->name
;
465 struct list_head
*p
, *head
;
467 spin_lock(&dcache_lock
);
468 spin_lock(&sbi
->lookup_lock
);
469 head
= &sbi
->expiring_list
;
470 list_for_each(p
, head
) {
471 struct autofs_info
*ino
;
472 struct dentry
*dentry
;
475 ino
= list_entry(p
, struct autofs_info
, expiring
);
476 dentry
= ino
->dentry
;
478 spin_lock(&dentry
->d_lock
);
480 /* Bad luck, we've already been dentry_iput */
481 if (!dentry
->d_inode
)
484 qstr
= &dentry
->d_name
;
486 if (dentry
->d_name
.hash
!= hash
)
488 if (dentry
->d_parent
!= parent
)
491 if (qstr
->len
!= len
)
493 if (memcmp(qstr
->name
, str
, len
))
496 if (d_unhashed(dentry
)) {
498 spin_unlock(&dentry
->d_lock
);
499 spin_unlock(&sbi
->lookup_lock
);
500 spin_unlock(&dcache_lock
);
504 spin_unlock(&dentry
->d_lock
);
506 spin_unlock(&sbi
->lookup_lock
);
507 spin_unlock(&dcache_lock
);
512 /* Lookups in the root directory */
513 static struct dentry
*autofs4_lookup(struct inode
*dir
, struct dentry
*dentry
, struct nameidata
*nd
)
515 struct autofs_sb_info
*sbi
;
516 struct autofs_info
*ino
;
517 struct dentry
*expiring
, *unhashed
;
520 DPRINTK("name = %.*s",
521 dentry
->d_name
.len
, dentry
->d_name
.name
);
523 /* File name too long to exist */
524 if (dentry
->d_name
.len
> NAME_MAX
)
525 return ERR_PTR(-ENAMETOOLONG
);
527 sbi
= autofs4_sbi(dir
->i_sb
);
528 oz_mode
= autofs4_oz_mode(sbi
);
530 DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d",
531 current
->pid
, task_pgrp_nr(current
), sbi
->catatonic
, oz_mode
);
533 expiring
= autofs4_lookup_expiring(sbi
, dentry
->d_parent
, &dentry
->d_name
);
536 * If we are racing with expire the request might not
537 * be quite complete but the directory has been removed
538 * so it must have been successful, so just wait for it.
540 ino
= autofs4_dentry_ino(expiring
);
541 spin_lock(&sbi
->fs_lock
);
542 if (ino
->flags
& AUTOFS_INF_EXPIRING
) {
543 spin_unlock(&sbi
->fs_lock
);
544 DPRINTK("wait for incomplete expire %p name=%.*s",
545 expiring
, expiring
->d_name
.len
,
546 expiring
->d_name
.name
);
547 autofs4_wait(sbi
, expiring
, NFY_NONE
);
548 DPRINTK("request completed");
551 spin_unlock(&sbi
->fs_lock
);
553 spin_lock(&sbi
->lookup_lock
);
554 if (!list_empty(&ino
->expiring
))
555 list_del_init(&ino
->expiring
);
556 spin_unlock(&sbi
->lookup_lock
);
560 unhashed
= autofs4_lookup_active(sbi
, dentry
->d_parent
, &dentry
->d_name
);
565 * Mark the dentry incomplete but don't hash it. We do this
566 * to serialize our inode creation operations (symlink and
567 * mkdir) which prevents deadlock during the callback to
568 * the daemon. Subsequent user space lookups for the same
569 * dentry are placed on the wait queue while the daemon
570 * itself is allowed passage unresticted so the create
571 * operation itself can then hash the dentry. Finally,
572 * we check for the hashed dentry and return the newly
575 dentry
->d_op
= &autofs4_root_dentry_operations
;
578 * And we need to ensure that the same dentry is used for
579 * all following lookup calls until it is hashed so that
580 * the dentry flags are persistent throughout the request.
582 ino
= autofs4_init_ino(NULL
, sbi
, 0555);
584 return ERR_PTR(-ENOMEM
);
586 dentry
->d_fsdata
= ino
;
587 ino
->dentry
= dentry
;
589 spin_lock(&sbi
->lookup_lock
);
590 list_add(&ino
->active
, &sbi
->active_list
);
591 spin_unlock(&sbi
->lookup_lock
);
593 d_instantiate(dentry
, NULL
);
597 spin_lock(&dentry
->d_lock
);
598 dentry
->d_flags
|= DCACHE_AUTOFS_PENDING
;
599 spin_unlock(&dentry
->d_lock
);
600 if (dentry
->d_op
&& dentry
->d_op
->d_revalidate
) {
601 mutex_unlock(&dir
->i_mutex
);
602 (dentry
->d_op
->d_revalidate
)(dentry
, nd
);
603 mutex_lock(&dir
->i_mutex
);
608 * If we are still pending, check if we had to handle
609 * a signal. If so we can force a restart..
611 if (dentry
->d_flags
& DCACHE_AUTOFS_PENDING
) {
612 /* See if we were interrupted */
613 if (signal_pending(current
)) {
614 sigset_t
*sigset
= ¤t
->pending
.signal
;
615 if (sigismember (sigset
, SIGKILL
) ||
616 sigismember (sigset
, SIGQUIT
) ||
617 sigismember (sigset
, SIGINT
)) {
620 return ERR_PTR(-ERESTARTNOINTR
);
624 spin_lock(&dentry
->d_lock
);
625 dentry
->d_flags
&= ~DCACHE_AUTOFS_PENDING
;
626 spin_unlock(&dentry
->d_lock
);
631 * If this dentry is unhashed, then we shouldn't honour this
632 * lookup. Returning ENOENT here doesn't do the right thing
633 * for all system calls, but it should be OK for the operations
634 * we permit from an autofs.
636 if (!oz_mode
&& d_unhashed(dentry
)) {
638 * A user space application can (and has done in the past)
639 * remove and re-create this directory during the callback.
640 * This can leave us with an unhashed dentry, but a
641 * successful mount! So we need to perform another
642 * cached lookup in case the dentry now exists.
644 struct dentry
*parent
= dentry
->d_parent
;
645 struct dentry
*new = d_lookup(parent
, &dentry
->d_name
);
649 dentry
= ERR_PTR(-ENOENT
);
663 static int autofs4_dir_symlink(struct inode
*dir
,
664 struct dentry
*dentry
,
667 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
668 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
669 struct autofs_info
*p_ino
;
673 DPRINTK("%s <- %.*s", symname
,
674 dentry
->d_name
.len
, dentry
->d_name
.name
);
676 if (!autofs4_oz_mode(sbi
))
679 ino
= autofs4_init_ino(ino
, sbi
, S_IFLNK
| 0555);
683 spin_lock(&sbi
->lookup_lock
);
684 if (!list_empty(&ino
->active
))
685 list_del_init(&ino
->active
);
686 spin_unlock(&sbi
->lookup_lock
);
688 ino
->size
= strlen(symname
);
689 cp
= kmalloc(ino
->size
+ 1, GFP_KERNEL
);
691 if (!dentry
->d_fsdata
)
698 inode
= autofs4_get_inode(dir
->i_sb
, ino
);
701 if (!dentry
->d_fsdata
)
705 d_add(dentry
, inode
);
707 if (dir
== dir
->i_sb
->s_root
->d_inode
)
708 dentry
->d_op
= &autofs4_root_dentry_operations
;
710 dentry
->d_op
= &autofs4_dentry_operations
;
712 dentry
->d_fsdata
= ino
;
713 ino
->dentry
= dget(dentry
);
714 atomic_inc(&ino
->count
);
715 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
716 if (p_ino
&& dentry
->d_parent
!= dentry
)
717 atomic_inc(&p_ino
->count
);
721 dir
->i_mtime
= CURRENT_TIME
;
729 * Normal filesystems would do a "d_delete()" to tell the VFS dcache
730 * that the file no longer exists. However, doing that means that the
731 * VFS layer can turn the dentry into a negative dentry. We don't want
732 * this, because the unlink is probably the result of an expire.
733 * We simply d_drop it and add it to a expiring list in the super block,
734 * which allows the dentry lookup to check for an incomplete expire.
736 * If a process is blocked on the dentry waiting for the expire to finish,
737 * it will invalidate the dentry and try to mount with a new one.
739 * Also see autofs4_dir_rmdir()..
741 static int autofs4_dir_unlink(struct inode
*dir
, struct dentry
*dentry
)
743 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
744 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
745 struct autofs_info
*p_ino
;
747 /* This allows root to remove symlinks */
748 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
751 if (atomic_dec_and_test(&ino
->count
)) {
752 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
753 if (p_ino
&& dentry
->d_parent
!= dentry
)
754 atomic_dec(&p_ino
->count
);
758 dentry
->d_inode
->i_size
= 0;
759 clear_nlink(dentry
->d_inode
);
761 dir
->i_mtime
= CURRENT_TIME
;
763 spin_lock(&dcache_lock
);
764 spin_lock(&sbi
->lookup_lock
);
765 if (list_empty(&ino
->expiring
))
766 list_add(&ino
->expiring
, &sbi
->expiring_list
);
767 spin_unlock(&sbi
->lookup_lock
);
768 spin_lock(&dentry
->d_lock
);
770 spin_unlock(&dentry
->d_lock
);
771 spin_unlock(&dcache_lock
);
776 static int autofs4_dir_rmdir(struct inode
*dir
, struct dentry
*dentry
)
778 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
779 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
780 struct autofs_info
*p_ino
;
782 DPRINTK("dentry %p, removing %.*s",
783 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
785 if (!autofs4_oz_mode(sbi
))
788 spin_lock(&dcache_lock
);
789 if (!list_empty(&dentry
->d_subdirs
)) {
790 spin_unlock(&dcache_lock
);
793 spin_lock(&sbi
->lookup_lock
);
794 if (list_empty(&ino
->expiring
))
795 list_add(&ino
->expiring
, &sbi
->expiring_list
);
796 spin_unlock(&sbi
->lookup_lock
);
797 spin_lock(&dentry
->d_lock
);
799 spin_unlock(&dentry
->d_lock
);
800 spin_unlock(&dcache_lock
);
802 if (atomic_dec_and_test(&ino
->count
)) {
803 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
804 if (p_ino
&& dentry
->d_parent
!= dentry
)
805 atomic_dec(&p_ino
->count
);
808 dentry
->d_inode
->i_size
= 0;
809 clear_nlink(dentry
->d_inode
);
817 static int autofs4_dir_mkdir(struct inode
*dir
, struct dentry
*dentry
, int mode
)
819 struct autofs_sb_info
*sbi
= autofs4_sbi(dir
->i_sb
);
820 struct autofs_info
*ino
= autofs4_dentry_ino(dentry
);
821 struct autofs_info
*p_ino
;
824 if (!autofs4_oz_mode(sbi
))
827 DPRINTK("dentry %p, creating %.*s",
828 dentry
, dentry
->d_name
.len
, dentry
->d_name
.name
);
830 ino
= autofs4_init_ino(ino
, sbi
, S_IFDIR
| 0555);
834 spin_lock(&sbi
->lookup_lock
);
835 if (!list_empty(&ino
->active
))
836 list_del_init(&ino
->active
);
837 spin_unlock(&sbi
->lookup_lock
);
839 inode
= autofs4_get_inode(dir
->i_sb
, ino
);
841 if (!dentry
->d_fsdata
)
845 d_add(dentry
, inode
);
847 if (dir
== dir
->i_sb
->s_root
->d_inode
)
848 dentry
->d_op
= &autofs4_root_dentry_operations
;
850 dentry
->d_op
= &autofs4_dentry_operations
;
852 dentry
->d_fsdata
= ino
;
853 ino
->dentry
= dget(dentry
);
854 atomic_inc(&ino
->count
);
855 p_ino
= autofs4_dentry_ino(dentry
->d_parent
);
856 if (p_ino
&& dentry
->d_parent
!= dentry
)
857 atomic_inc(&p_ino
->count
);
860 dir
->i_mtime
= CURRENT_TIME
;
865 /* Get/set timeout ioctl() operation */
866 static inline int autofs4_get_set_timeout(struct autofs_sb_info
*sbi
,
867 unsigned long __user
*p
)
870 unsigned long ntimeout
;
872 if ((rv
= get_user(ntimeout
, p
)) ||
873 (rv
= put_user(sbi
->exp_timeout
/HZ
, p
)))
876 if (ntimeout
> ULONG_MAX
/HZ
)
877 sbi
->exp_timeout
= 0;
879 sbi
->exp_timeout
= ntimeout
* HZ
;
884 /* Return protocol version */
885 static inline int autofs4_get_protover(struct autofs_sb_info
*sbi
, int __user
*p
)
887 return put_user(sbi
->version
, p
);
890 /* Return protocol sub version */
891 static inline int autofs4_get_protosubver(struct autofs_sb_info
*sbi
, int __user
*p
)
893 return put_user(sbi
->sub_version
, p
);
897 * Tells the daemon whether we need to reghost or not. Also, clears
898 * the reghost_needed flag.
900 static inline int autofs4_ask_reghost(struct autofs_sb_info
*sbi
, int __user
*p
)
904 DPRINTK("returning %d", sbi
->needs_reghost
);
906 status
= put_user(sbi
->needs_reghost
, p
);
910 sbi
->needs_reghost
= 0;
915 * Enable / Disable reghosting ioctl() operation
917 static inline int autofs4_toggle_reghost(struct autofs_sb_info
*sbi
, int __user
*p
)
922 status
= get_user(val
, p
);
924 DPRINTK("reghost = %d", val
);
929 /* turn on/off reghosting, with the val */
930 sbi
->reghost_enabled
= val
;
935 * Tells the daemon whether it can umount the autofs mount.
937 static inline int autofs4_ask_umount(struct vfsmount
*mnt
, int __user
*p
)
944 DPRINTK("returning %d", status
);
946 status
= put_user(status
, p
);
951 /* Identify autofs4_dentries - this is so we can tell if there's
952 an extra dentry refcount or not. We only hold a refcount on the
953 dentry if its non-negative (ie, d_inode != NULL)
955 int is_autofs4_dentry(struct dentry
*dentry
)
957 return dentry
&& dentry
->d_inode
&&
958 (dentry
->d_op
== &autofs4_root_dentry_operations
||
959 dentry
->d_op
== &autofs4_dentry_operations
) &&
960 dentry
->d_fsdata
!= NULL
;
964 * ioctl()'s on the root directory is the chief method for the daemon to
965 * generate kernel reactions
967 static int autofs4_root_ioctl(struct inode
*inode
, struct file
*filp
,
968 unsigned int cmd
, unsigned long arg
)
970 struct autofs_sb_info
*sbi
= autofs4_sbi(inode
->i_sb
);
971 void __user
*p
= (void __user
*)arg
;
973 DPRINTK("cmd = 0x%08x, arg = 0x%08lx, sbi = %p, pgrp = %u",
974 cmd
,arg
,sbi
,task_pgrp_nr(current
));
976 if (_IOC_TYPE(cmd
) != _IOC_TYPE(AUTOFS_IOC_FIRST
) ||
977 _IOC_NR(cmd
) - _IOC_NR(AUTOFS_IOC_FIRST
) >= AUTOFS_IOC_COUNT
)
980 if (!autofs4_oz_mode(sbi
) && !capable(CAP_SYS_ADMIN
))
984 case AUTOFS_IOC_READY
: /* Wait queue: go ahead and retry */
985 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,0);
986 case AUTOFS_IOC_FAIL
: /* Wait queue: fail with ENOENT */
987 return autofs4_wait_release(sbi
,(autofs_wqt_t
)arg
,-ENOENT
);
988 case AUTOFS_IOC_CATATONIC
: /* Enter catatonic mode (daemon shutdown) */
989 autofs4_catatonic_mode(sbi
);
991 case AUTOFS_IOC_PROTOVER
: /* Get protocol version */
992 return autofs4_get_protover(sbi
, p
);
993 case AUTOFS_IOC_PROTOSUBVER
: /* Get protocol sub version */
994 return autofs4_get_protosubver(sbi
, p
);
995 case AUTOFS_IOC_SETTIMEOUT
:
996 return autofs4_get_set_timeout(sbi
, p
);
998 case AUTOFS_IOC_TOGGLEREGHOST
:
999 return autofs4_toggle_reghost(sbi
, p
);
1000 case AUTOFS_IOC_ASKREGHOST
:
1001 return autofs4_ask_reghost(sbi
, p
);
1003 case AUTOFS_IOC_ASKUMOUNT
:
1004 return autofs4_ask_umount(filp
->f_path
.mnt
, p
);
1006 /* return a single thing to expire */
1007 case AUTOFS_IOC_EXPIRE
:
1008 return autofs4_expire_run(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);
1009 /* same as above, but can send multiple expires through pipe */
1010 case AUTOFS_IOC_EXPIRE_MULTI
:
1011 return autofs4_expire_multi(inode
->i_sb
,filp
->f_path
.mnt
,sbi
, p
);