ACPI: pci_root: simplify list traversals
[linux-2.6/linux-acpi-2.6.git] / fs / autofs4 / dev-ioctl.c
blob84168c0dcc2d2aa76d7a45233fe7164959e34091
1 /*
2 * Copyright 2008 Red Hat, Inc. All rights reserved.
3 * Copyright 2008 Ian Kent <raven@themaw.net>
5 * This file is part of the Linux kernel and is made available under
6 * the terms of the GNU General Public License, version 2, or at your
7 * option, any later version, incorporated herein by reference.
8 */
10 #include <linux/module.h>
11 #include <linux/vmalloc.h>
12 #include <linux/miscdevice.h>
13 #include <linux/init.h>
14 #include <linux/wait.h>
15 #include <linux/namei.h>
16 #include <linux/fcntl.h>
17 #include <linux/file.h>
18 #include <linux/fdtable.h>
19 #include <linux/sched.h>
20 #include <linux/compat.h>
21 #include <linux/syscalls.h>
22 #include <linux/smp_lock.h>
23 #include <linux/magic.h>
24 #include <linux/dcache.h>
25 #include <linux/uaccess.h>
27 #include "autofs_i.h"
30 * This module implements an interface for routing autofs ioctl control
31 * commands via a miscellaneous device file.
33 * The alternate interface is needed because we need to be able open
34 * an ioctl file descriptor on an autofs mount that may be covered by
35 * another mount. This situation arises when starting automount(8)
36 * or other user space daemon which uses direct mounts or offset
37 * mounts (used for autofs lazy mount/umount of nested mount trees),
38 * which have been left busy at at service shutdown.
41 #define AUTOFS_DEV_IOCTL_SIZE sizeof(struct autofs_dev_ioctl)
43 typedef int (*ioctl_fn)(struct file *, struct autofs_sb_info *,
44 struct autofs_dev_ioctl *);
46 static int check_name(const char *name)
48 if (!strchr(name, '/'))
49 return -EINVAL;
50 return 0;
54 * Check a string doesn't overrun the chunk of
55 * memory we copied from user land.
57 static int invalid_str(char *str, size_t size)
59 if (memchr(str, 0, size))
60 return 0;
61 return -EINVAL;
65 * Check that the user compiled against correct version of autofs
66 * misc device code.
68 * As well as checking the version compatibility this always copies
69 * the kernel interface version out.
71 static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
73 int err = 0;
75 if ((AUTOFS_DEV_IOCTL_VERSION_MAJOR != param->ver_major) ||
76 (AUTOFS_DEV_IOCTL_VERSION_MINOR < param->ver_minor)) {
77 AUTOFS_WARN("ioctl control interface version mismatch: "
78 "kernel(%u.%u), user(%u.%u), cmd(%d)",
79 AUTOFS_DEV_IOCTL_VERSION_MAJOR,
80 AUTOFS_DEV_IOCTL_VERSION_MINOR,
81 param->ver_major, param->ver_minor, cmd);
82 err = -EINVAL;
85 /* Fill in the kernel version. */
86 param->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
87 param->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
89 return err;
93 * Copy parameter control struct, including a possible path allocated
94 * at the end of the struct.
96 static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in)
98 struct autofs_dev_ioctl tmp, *ads;
100 if (copy_from_user(&tmp, in, sizeof(tmp)))
101 return ERR_PTR(-EFAULT);
103 if (tmp.size < sizeof(tmp))
104 return ERR_PTR(-EINVAL);
106 ads = kmalloc(tmp.size, GFP_KERNEL);
107 if (!ads)
108 return ERR_PTR(-ENOMEM);
110 if (copy_from_user(ads, in, tmp.size)) {
111 kfree(ads);
112 return ERR_PTR(-EFAULT);
115 return ads;
118 static inline void free_dev_ioctl(struct autofs_dev_ioctl *param)
120 kfree(param);
121 return;
125 * Check sanity of parameter control fields and if a path is present
126 * check that it is terminated and contains at least one "/".
128 static int validate_dev_ioctl(int cmd, struct autofs_dev_ioctl *param)
130 int err;
132 err = check_dev_ioctl_version(cmd, param);
133 if (err) {
134 AUTOFS_WARN("invalid device control module version "
135 "supplied for cmd(0x%08x)", cmd);
136 goto out;
139 if (param->size > sizeof(*param)) {
140 err = invalid_str(param->path, param->size - sizeof(*param));
141 if (err) {
142 AUTOFS_WARN(
143 "path string terminator missing for cmd(0x%08x)",
144 cmd);
145 goto out;
148 err = check_name(param->path);
149 if (err) {
150 AUTOFS_WARN("invalid path supplied for cmd(0x%08x)",
151 cmd);
152 goto out;
156 err = 0;
157 out:
158 return err;
162 * Get the autofs super block info struct from the file opened on
163 * the autofs mount point.
165 static struct autofs_sb_info *autofs_dev_ioctl_sbi(struct file *f)
167 struct autofs_sb_info *sbi = NULL;
168 struct inode *inode;
170 if (f) {
171 inode = f->f_path.dentry->d_inode;
172 sbi = autofs4_sbi(inode->i_sb);
174 return sbi;
177 /* Return autofs module protocol version */
178 static int autofs_dev_ioctl_protover(struct file *fp,
179 struct autofs_sb_info *sbi,
180 struct autofs_dev_ioctl *param)
182 param->protover.version = sbi->version;
183 return 0;
186 /* Return autofs module protocol sub version */
187 static int autofs_dev_ioctl_protosubver(struct file *fp,
188 struct autofs_sb_info *sbi,
189 struct autofs_dev_ioctl *param)
191 param->protosubver.sub_version = sbi->sub_version;
192 return 0;
196 * Walk down the mount stack looking for an autofs mount that
197 * has the requested device number (aka. new_encode_dev(sb->s_dev).
199 static int autofs_dev_ioctl_find_super(struct nameidata *nd, dev_t devno)
201 struct dentry *dentry;
202 struct inode *inode;
203 struct super_block *sb;
204 dev_t s_dev;
205 unsigned int err;
207 err = -ENOENT;
209 /* Lookup the dentry name at the base of our mount point */
210 dentry = d_lookup(nd->path.dentry, &nd->last);
211 if (!dentry)
212 goto out;
214 dput(nd->path.dentry);
215 nd->path.dentry = dentry;
217 /* And follow the mount stack looking for our autofs mount */
218 while (follow_down(&nd->path.mnt, &nd->path.dentry)) {
219 inode = nd->path.dentry->d_inode;
220 if (!inode)
221 break;
223 sb = inode->i_sb;
224 s_dev = new_encode_dev(sb->s_dev);
225 if (devno == s_dev) {
226 if (sb->s_magic == AUTOFS_SUPER_MAGIC) {
227 err = 0;
228 break;
232 out:
233 return err;
237 * Walk down the mount stack looking for an autofs mount that
238 * has the requested mount type (ie. indirect, direct or offset).
240 static int autofs_dev_ioctl_find_sbi_type(struct nameidata *nd, unsigned int type)
242 struct dentry *dentry;
243 struct autofs_info *ino;
244 unsigned int err;
246 err = -ENOENT;
248 /* Lookup the dentry name at the base of our mount point */
249 dentry = d_lookup(nd->path.dentry, &nd->last);
250 if (!dentry)
251 goto out;
253 dput(nd->path.dentry);
254 nd->path.dentry = dentry;
256 /* And follow the mount stack looking for our autofs mount */
257 while (follow_down(&nd->path.mnt, &nd->path.dentry)) {
258 ino = autofs4_dentry_ino(nd->path.dentry);
259 if (ino && ino->sbi->type & type) {
260 err = 0;
261 break;
264 out:
265 return err;
268 static void autofs_dev_ioctl_fd_install(unsigned int fd, struct file *file)
270 struct files_struct *files = current->files;
271 struct fdtable *fdt;
273 spin_lock(&files->file_lock);
274 fdt = files_fdtable(files);
275 BUG_ON(fdt->fd[fd] != NULL);
276 rcu_assign_pointer(fdt->fd[fd], file);
277 FD_SET(fd, fdt->close_on_exec);
278 spin_unlock(&files->file_lock);
283 * Open a file descriptor on the autofs mount point corresponding
284 * to the given path and device number (aka. new_encode_dev(sb->s_dev)).
286 static int autofs_dev_ioctl_open_mountpoint(const char *path, dev_t devid)
288 struct file *filp;
289 struct nameidata nd;
290 int err, fd;
292 fd = get_unused_fd();
293 if (likely(fd >= 0)) {
294 /* Get nameidata of the parent directory */
295 err = path_lookup(path, LOOKUP_PARENT, &nd);
296 if (err)
297 goto out;
300 * Search down, within the parent, looking for an
301 * autofs super block that has the device number
302 * corresponding to the autofs fs we want to open.
304 err = autofs_dev_ioctl_find_super(&nd, devid);
305 if (err) {
306 path_put(&nd.path);
307 goto out;
310 filp = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY,
311 current_cred());
312 if (IS_ERR(filp)) {
313 err = PTR_ERR(filp);
314 goto out;
317 autofs_dev_ioctl_fd_install(fd, filp);
320 return fd;
322 out:
323 put_unused_fd(fd);
324 return err;
327 /* Open a file descriptor on an autofs mount point */
328 static int autofs_dev_ioctl_openmount(struct file *fp,
329 struct autofs_sb_info *sbi,
330 struct autofs_dev_ioctl *param)
332 const char *path;
333 dev_t devid;
334 int err, fd;
336 /* param->path has already been checked */
337 if (!param->openmount.devid)
338 return -EINVAL;
340 param->ioctlfd = -1;
342 path = param->path;
343 devid = param->openmount.devid;
345 err = 0;
346 fd = autofs_dev_ioctl_open_mountpoint(path, devid);
347 if (unlikely(fd < 0)) {
348 err = fd;
349 goto out;
352 param->ioctlfd = fd;
353 out:
354 return err;
357 /* Close file descriptor allocated above (user can also use close(2)). */
358 static int autofs_dev_ioctl_closemount(struct file *fp,
359 struct autofs_sb_info *sbi,
360 struct autofs_dev_ioctl *param)
362 return sys_close(param->ioctlfd);
366 * Send "ready" status for an existing wait (either a mount or an expire
367 * request).
369 static int autofs_dev_ioctl_ready(struct file *fp,
370 struct autofs_sb_info *sbi,
371 struct autofs_dev_ioctl *param)
373 autofs_wqt_t token;
375 token = (autofs_wqt_t) param->ready.token;
376 return autofs4_wait_release(sbi, token, 0);
380 * Send "fail" status for an existing wait (either a mount or an expire
381 * request).
383 static int autofs_dev_ioctl_fail(struct file *fp,
384 struct autofs_sb_info *sbi,
385 struct autofs_dev_ioctl *param)
387 autofs_wqt_t token;
388 int status;
390 token = (autofs_wqt_t) param->fail.token;
391 status = param->fail.status ? param->fail.status : -ENOENT;
392 return autofs4_wait_release(sbi, token, status);
396 * Set the pipe fd for kernel communication to the daemon.
398 * Normally this is set at mount using an option but if we
399 * are reconnecting to a busy mount then we need to use this
400 * to tell the autofs mount about the new kernel pipe fd. In
401 * order to protect mounts against incorrectly setting the
402 * pipefd we also require that the autofs mount be catatonic.
404 * This also sets the process group id used to identify the
405 * controlling process (eg. the owning automount(8) daemon).
407 static int autofs_dev_ioctl_setpipefd(struct file *fp,
408 struct autofs_sb_info *sbi,
409 struct autofs_dev_ioctl *param)
411 int pipefd;
412 int err = 0;
414 if (param->setpipefd.pipefd == -1)
415 return -EINVAL;
417 pipefd = param->setpipefd.pipefd;
419 mutex_lock(&sbi->wq_mutex);
420 if (!sbi->catatonic) {
421 mutex_unlock(&sbi->wq_mutex);
422 return -EBUSY;
423 } else {
424 struct file *pipe = fget(pipefd);
425 if (!pipe->f_op || !pipe->f_op->write) {
426 err = -EPIPE;
427 fput(pipe);
428 goto out;
430 sbi->oz_pgrp = task_pgrp_nr(current);
431 sbi->pipefd = pipefd;
432 sbi->pipe = pipe;
433 sbi->catatonic = 0;
435 out:
436 mutex_unlock(&sbi->wq_mutex);
437 return err;
441 * Make the autofs mount point catatonic, no longer responsive to
442 * mount requests. Also closes the kernel pipe file descriptor.
444 static int autofs_dev_ioctl_catatonic(struct file *fp,
445 struct autofs_sb_info *sbi,
446 struct autofs_dev_ioctl *param)
448 autofs4_catatonic_mode(sbi);
449 return 0;
452 /* Set the autofs mount timeout */
453 static int autofs_dev_ioctl_timeout(struct file *fp,
454 struct autofs_sb_info *sbi,
455 struct autofs_dev_ioctl *param)
457 unsigned long timeout;
459 timeout = param->timeout.timeout;
460 param->timeout.timeout = sbi->exp_timeout / HZ;
461 sbi->exp_timeout = timeout * HZ;
462 return 0;
466 * Return the uid and gid of the last request for the mount
468 * When reconstructing an autofs mount tree with active mounts
469 * we need to re-connect to mounts that may have used the original
470 * process uid and gid (or string variations of them) for mount
471 * lookups within the map entry.
473 static int autofs_dev_ioctl_requester(struct file *fp,
474 struct autofs_sb_info *sbi,
475 struct autofs_dev_ioctl *param)
477 struct autofs_info *ino;
478 struct nameidata nd;
479 const char *path;
480 dev_t devid;
481 int err = -ENOENT;
483 if (param->size <= sizeof(*param)) {
484 err = -EINVAL;
485 goto out;
488 path = param->path;
489 devid = new_encode_dev(sbi->sb->s_dev);
491 param->requester.uid = param->requester.gid = -1;
493 /* Get nameidata of the parent directory */
494 err = path_lookup(path, LOOKUP_PARENT, &nd);
495 if (err)
496 goto out;
498 err = autofs_dev_ioctl_find_super(&nd, devid);
499 if (err)
500 goto out_release;
502 ino = autofs4_dentry_ino(nd.path.dentry);
503 if (ino) {
504 err = 0;
505 autofs4_expire_wait(nd.path.dentry);
506 spin_lock(&sbi->fs_lock);
507 param->requester.uid = ino->uid;
508 param->requester.gid = ino->gid;
509 spin_unlock(&sbi->fs_lock);
512 out_release:
513 path_put(&nd.path);
514 out:
515 return err;
519 * Call repeatedly until it returns -EAGAIN, meaning there's nothing
520 * more that can be done.
522 static int autofs_dev_ioctl_expire(struct file *fp,
523 struct autofs_sb_info *sbi,
524 struct autofs_dev_ioctl *param)
526 struct vfsmount *mnt;
527 int how;
529 how = param->expire.how;
530 mnt = fp->f_path.mnt;
532 return autofs4_do_expire_multi(sbi->sb, mnt, sbi, how);
535 /* Check if autofs mount point is in use */
536 static int autofs_dev_ioctl_askumount(struct file *fp,
537 struct autofs_sb_info *sbi,
538 struct autofs_dev_ioctl *param)
540 param->askumount.may_umount = 0;
541 if (may_umount(fp->f_path.mnt))
542 param->askumount.may_umount = 1;
543 return 0;
547 * Check if the given path is a mountpoint.
549 * If we are supplied with the file descriptor of an autofs
550 * mount we're looking for a specific mount. In this case
551 * the path is considered a mountpoint if it is itself a
552 * mountpoint or contains a mount, such as a multi-mount
553 * without a root mount. In this case we return 1 if the
554 * path is a mount point and the super magic of the covering
555 * mount if there is one or 0 if it isn't a mountpoint.
557 * If we aren't supplied with a file descriptor then we
558 * lookup the nameidata of the path and check if it is the
559 * root of a mount. If a type is given we are looking for
560 * a particular autofs mount and if we don't find a match
561 * we return fail. If the located nameidata path is the
562 * root of a mount we return 1 along with the super magic
563 * of the mount or 0 otherwise.
565 * In both cases the the device number (as returned by
566 * new_encode_dev()) is also returned.
568 static int autofs_dev_ioctl_ismountpoint(struct file *fp,
569 struct autofs_sb_info *sbi,
570 struct autofs_dev_ioctl *param)
572 struct nameidata nd;
573 const char *path;
574 unsigned int type;
575 unsigned int devid, magic;
576 int err = -ENOENT;
578 if (param->size <= sizeof(*param)) {
579 err = -EINVAL;
580 goto out;
583 path = param->path;
584 type = param->ismountpoint.in.type;
586 param->ismountpoint.out.devid = devid = 0;
587 param->ismountpoint.out.magic = magic = 0;
589 if (!fp || param->ioctlfd == -1) {
590 if (autofs_type_any(type)) {
591 struct super_block *sb;
593 err = path_lookup(path, LOOKUP_FOLLOW, &nd);
594 if (err)
595 goto out;
597 sb = nd.path.dentry->d_sb;
598 devid = new_encode_dev(sb->s_dev);
599 } else {
600 struct autofs_info *ino;
602 err = path_lookup(path, LOOKUP_PARENT, &nd);
603 if (err)
604 goto out;
606 err = autofs_dev_ioctl_find_sbi_type(&nd, type);
607 if (err)
608 goto out_release;
610 ino = autofs4_dentry_ino(nd.path.dentry);
611 devid = autofs4_get_dev(ino->sbi);
614 err = 0;
615 if (nd.path.dentry->d_inode &&
616 nd.path.mnt->mnt_root == nd.path.dentry) {
617 err = 1;
618 magic = nd.path.dentry->d_inode->i_sb->s_magic;
620 } else {
621 dev_t dev = autofs4_get_dev(sbi);
623 err = path_lookup(path, LOOKUP_PARENT, &nd);
624 if (err)
625 goto out;
627 err = autofs_dev_ioctl_find_super(&nd, dev);
628 if (err)
629 goto out_release;
631 devid = dev;
633 err = have_submounts(nd.path.dentry);
635 if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
636 if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
637 struct inode *inode = nd.path.dentry->d_inode;
638 magic = inode->i_sb->s_magic;
643 param->ismountpoint.out.devid = devid;
644 param->ismountpoint.out.magic = magic;
646 out_release:
647 path_put(&nd.path);
648 out:
649 return err;
653 * Our range of ioctl numbers isn't 0 based so we need to shift
654 * the array index by _IOC_NR(AUTOFS_CTL_IOC_FIRST) for the table
655 * lookup.
657 #define cmd_idx(cmd) (cmd - _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST))
659 static ioctl_fn lookup_dev_ioctl(unsigned int cmd)
661 static struct {
662 int cmd;
663 ioctl_fn fn;
664 } _ioctls[] = {
665 {cmd_idx(AUTOFS_DEV_IOCTL_VERSION_CMD), NULL},
666 {cmd_idx(AUTOFS_DEV_IOCTL_PROTOVER_CMD),
667 autofs_dev_ioctl_protover},
668 {cmd_idx(AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD),
669 autofs_dev_ioctl_protosubver},
670 {cmd_idx(AUTOFS_DEV_IOCTL_OPENMOUNT_CMD),
671 autofs_dev_ioctl_openmount},
672 {cmd_idx(AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD),
673 autofs_dev_ioctl_closemount},
674 {cmd_idx(AUTOFS_DEV_IOCTL_READY_CMD),
675 autofs_dev_ioctl_ready},
676 {cmd_idx(AUTOFS_DEV_IOCTL_FAIL_CMD),
677 autofs_dev_ioctl_fail},
678 {cmd_idx(AUTOFS_DEV_IOCTL_SETPIPEFD_CMD),
679 autofs_dev_ioctl_setpipefd},
680 {cmd_idx(AUTOFS_DEV_IOCTL_CATATONIC_CMD),
681 autofs_dev_ioctl_catatonic},
682 {cmd_idx(AUTOFS_DEV_IOCTL_TIMEOUT_CMD),
683 autofs_dev_ioctl_timeout},
684 {cmd_idx(AUTOFS_DEV_IOCTL_REQUESTER_CMD),
685 autofs_dev_ioctl_requester},
686 {cmd_idx(AUTOFS_DEV_IOCTL_EXPIRE_CMD),
687 autofs_dev_ioctl_expire},
688 {cmd_idx(AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD),
689 autofs_dev_ioctl_askumount},
690 {cmd_idx(AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD),
691 autofs_dev_ioctl_ismountpoint}
693 unsigned int idx = cmd_idx(cmd);
695 return (idx >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[idx].fn;
698 /* ioctl dispatcher */
699 static int _autofs_dev_ioctl(unsigned int command, struct autofs_dev_ioctl __user *user)
701 struct autofs_dev_ioctl *param;
702 struct file *fp;
703 struct autofs_sb_info *sbi;
704 unsigned int cmd_first, cmd;
705 ioctl_fn fn = NULL;
706 int err = 0;
708 /* only root can play with this */
709 if (!capable(CAP_SYS_ADMIN))
710 return -EPERM;
712 cmd_first = _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST);
713 cmd = _IOC_NR(command);
715 if (_IOC_TYPE(command) != _IOC_TYPE(AUTOFS_DEV_IOCTL_IOC_FIRST) ||
716 cmd - cmd_first >= AUTOFS_DEV_IOCTL_IOC_COUNT) {
717 return -ENOTTY;
720 /* Copy the parameters into kernel space. */
721 param = copy_dev_ioctl(user);
722 if (IS_ERR(param))
723 return PTR_ERR(param);
725 err = validate_dev_ioctl(command, param);
726 if (err)
727 goto out;
729 /* The validate routine above always sets the version */
730 if (cmd == AUTOFS_DEV_IOCTL_VERSION_CMD)
731 goto done;
733 fn = lookup_dev_ioctl(cmd);
734 if (!fn) {
735 AUTOFS_WARN("unknown command 0x%08x", command);
736 return -ENOTTY;
739 fp = NULL;
740 sbi = NULL;
743 * For obvious reasons the openmount can't have a file
744 * descriptor yet. We don't take a reference to the
745 * file during close to allow for immediate release.
747 if (cmd != AUTOFS_DEV_IOCTL_OPENMOUNT_CMD &&
748 cmd != AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD) {
749 fp = fget(param->ioctlfd);
750 if (!fp) {
751 if (cmd == AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD)
752 goto cont;
753 err = -EBADF;
754 goto out;
757 if (!fp->f_op) {
758 err = -ENOTTY;
759 fput(fp);
760 goto out;
763 sbi = autofs_dev_ioctl_sbi(fp);
764 if (!sbi || sbi->magic != AUTOFS_SBI_MAGIC) {
765 err = -EINVAL;
766 fput(fp);
767 goto out;
771 * Admin needs to be able to set the mount catatonic in
772 * order to be able to perform the re-open.
774 if (!autofs4_oz_mode(sbi) &&
775 cmd != AUTOFS_DEV_IOCTL_CATATONIC_CMD) {
776 err = -EACCES;
777 fput(fp);
778 goto out;
781 cont:
782 err = fn(fp, sbi, param);
784 if (fp)
785 fput(fp);
786 done:
787 if (err >= 0 && copy_to_user(user, param, AUTOFS_DEV_IOCTL_SIZE))
788 err = -EFAULT;
789 out:
790 free_dev_ioctl(param);
791 return err;
794 static long autofs_dev_ioctl(struct file *file, uint command, ulong u)
796 int err;
797 err = _autofs_dev_ioctl(command, (struct autofs_dev_ioctl __user *) u);
798 return (long) err;
801 #ifdef CONFIG_COMPAT
802 static long autofs_dev_ioctl_compat(struct file *file, uint command, ulong u)
804 return (long) autofs_dev_ioctl(file, command, (ulong) compat_ptr(u));
806 #else
807 #define autofs_dev_ioctl_compat NULL
808 #endif
810 static const struct file_operations _dev_ioctl_fops = {
811 .unlocked_ioctl = autofs_dev_ioctl,
812 .compat_ioctl = autofs_dev_ioctl_compat,
813 .owner = THIS_MODULE,
816 static struct miscdevice _autofs_dev_ioctl_misc = {
817 .minor = MISC_DYNAMIC_MINOR,
818 .name = AUTOFS_DEVICE_NAME,
819 .fops = &_dev_ioctl_fops
822 /* Register/deregister misc character device */
823 int autofs_dev_ioctl_init(void)
825 int r;
827 r = misc_register(&_autofs_dev_ioctl_misc);
828 if (r) {
829 AUTOFS_ERROR("misc_register failed for control device");
830 return r;
833 return 0;
836 void autofs_dev_ioctl_exit(void)
838 misc_deregister(&_autofs_dev_ioctl_misc);
839 return;