x86, PAT: Remove page granularity tracking for vm_insert_pfn maps
[linux-2.6/mini2440.git] / fs / autofs4 / dev-ioctl.c
blob9e5ae8a4f5c867bf1ddb81525cd260028d8d3c9e
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, void *end)
59 while ((void *) str <= end)
60 if (!*str++)
61 return 0;
62 return -EINVAL;
66 * Check that the user compiled against correct version of autofs
67 * misc device code.
69 * As well as checking the version compatibility this always copies
70 * the kernel interface version out.
72 static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
74 int err = 0;
76 if ((AUTOFS_DEV_IOCTL_VERSION_MAJOR != param->ver_major) ||
77 (AUTOFS_DEV_IOCTL_VERSION_MINOR < param->ver_minor)) {
78 AUTOFS_WARN("ioctl control interface version mismatch: "
79 "kernel(%u.%u), user(%u.%u), cmd(%d)",
80 AUTOFS_DEV_IOCTL_VERSION_MAJOR,
81 AUTOFS_DEV_IOCTL_VERSION_MINOR,
82 param->ver_major, param->ver_minor, cmd);
83 err = -EINVAL;
86 /* Fill in the kernel version. */
87 param->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
88 param->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
90 return err;
94 * Copy parameter control struct, including a possible path allocated
95 * at the end of the struct.
97 static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in)
99 struct autofs_dev_ioctl tmp, *ads;
101 if (copy_from_user(&tmp, in, sizeof(tmp)))
102 return ERR_PTR(-EFAULT);
104 if (tmp.size < sizeof(tmp))
105 return ERR_PTR(-EINVAL);
107 ads = kmalloc(tmp.size, GFP_KERNEL);
108 if (!ads)
109 return ERR_PTR(-ENOMEM);
111 if (copy_from_user(ads, in, tmp.size)) {
112 kfree(ads);
113 return ERR_PTR(-EFAULT);
116 return ads;
119 static inline void free_dev_ioctl(struct autofs_dev_ioctl *param)
121 kfree(param);
122 return;
126 * Check sanity of parameter control fields and if a path is present
127 * check that it is terminated and contains at least one "/".
129 static int validate_dev_ioctl(int cmd, struct autofs_dev_ioctl *param)
131 int err;
133 err = check_dev_ioctl_version(cmd, param);
134 if (err) {
135 AUTOFS_WARN("invalid device control module version "
136 "supplied for cmd(0x%08x)", cmd);
137 goto out;
140 if (param->size > sizeof(*param)) {
141 err = invalid_str(param->path,
142 (void *) ((size_t) param + param->size));
143 if (err) {
144 AUTOFS_WARN(
145 "path string terminator missing for cmd(0x%08x)",
146 cmd);
147 goto out;
150 err = check_name(param->path);
151 if (err) {
152 AUTOFS_WARN("invalid path supplied for cmd(0x%08x)",
153 cmd);
154 goto out;
158 err = 0;
159 out:
160 return err;
164 * Get the autofs super block info struct from the file opened on
165 * the autofs mount point.
167 static struct autofs_sb_info *autofs_dev_ioctl_sbi(struct file *f)
169 struct autofs_sb_info *sbi = NULL;
170 struct inode *inode;
172 if (f) {
173 inode = f->f_path.dentry->d_inode;
174 sbi = autofs4_sbi(inode->i_sb);
176 return sbi;
179 /* Return autofs module protocol version */
180 static int autofs_dev_ioctl_protover(struct file *fp,
181 struct autofs_sb_info *sbi,
182 struct autofs_dev_ioctl *param)
184 param->protover.version = sbi->version;
185 return 0;
188 /* Return autofs module protocol sub version */
189 static int autofs_dev_ioctl_protosubver(struct file *fp,
190 struct autofs_sb_info *sbi,
191 struct autofs_dev_ioctl *param)
193 param->protosubver.sub_version = sbi->sub_version;
194 return 0;
198 * Walk down the mount stack looking for an autofs mount that
199 * has the requested device number (aka. new_encode_dev(sb->s_dev).
201 static int autofs_dev_ioctl_find_super(struct nameidata *nd, dev_t devno)
203 struct dentry *dentry;
204 struct inode *inode;
205 struct super_block *sb;
206 dev_t s_dev;
207 unsigned int err;
209 err = -ENOENT;
211 /* Lookup the dentry name at the base of our mount point */
212 dentry = d_lookup(nd->path.dentry, &nd->last);
213 if (!dentry)
214 goto out;
216 dput(nd->path.dentry);
217 nd->path.dentry = dentry;
219 /* And follow the mount stack looking for our autofs mount */
220 while (follow_down(&nd->path.mnt, &nd->path.dentry)) {
221 inode = nd->path.dentry->d_inode;
222 if (!inode)
223 break;
225 sb = inode->i_sb;
226 s_dev = new_encode_dev(sb->s_dev);
227 if (devno == s_dev) {
228 if (sb->s_magic == AUTOFS_SUPER_MAGIC) {
229 err = 0;
230 break;
234 out:
235 return err;
239 * Walk down the mount stack looking for an autofs mount that
240 * has the requested mount type (ie. indirect, direct or offset).
242 static int autofs_dev_ioctl_find_sbi_type(struct nameidata *nd, unsigned int type)
244 struct dentry *dentry;
245 struct autofs_info *ino;
246 unsigned int err;
248 err = -ENOENT;
250 /* Lookup the dentry name at the base of our mount point */
251 dentry = d_lookup(nd->path.dentry, &nd->last);
252 if (!dentry)
253 goto out;
255 dput(nd->path.dentry);
256 nd->path.dentry = dentry;
258 /* And follow the mount stack looking for our autofs mount */
259 while (follow_down(&nd->path.mnt, &nd->path.dentry)) {
260 ino = autofs4_dentry_ino(nd->path.dentry);
261 if (ino && ino->sbi->type & type) {
262 err = 0;
263 break;
266 out:
267 return err;
270 static void autofs_dev_ioctl_fd_install(unsigned int fd, struct file *file)
272 struct files_struct *files = current->files;
273 struct fdtable *fdt;
275 spin_lock(&files->file_lock);
276 fdt = files_fdtable(files);
277 BUG_ON(fdt->fd[fd] != NULL);
278 rcu_assign_pointer(fdt->fd[fd], file);
279 FD_SET(fd, fdt->close_on_exec);
280 spin_unlock(&files->file_lock);
285 * Open a file descriptor on the autofs mount point corresponding
286 * to the given path and device number (aka. new_encode_dev(sb->s_dev)).
288 static int autofs_dev_ioctl_open_mountpoint(const char *path, dev_t devid)
290 struct file *filp;
291 struct nameidata nd;
292 int err, fd;
294 fd = get_unused_fd();
295 if (likely(fd >= 0)) {
296 /* Get nameidata of the parent directory */
297 err = path_lookup(path, LOOKUP_PARENT, &nd);
298 if (err)
299 goto out;
302 * Search down, within the parent, looking for an
303 * autofs super block that has the device number
304 * corresponding to the autofs fs we want to open.
306 err = autofs_dev_ioctl_find_super(&nd, devid);
307 if (err) {
308 path_put(&nd.path);
309 goto out;
312 filp = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY,
313 current_cred());
314 if (IS_ERR(filp)) {
315 err = PTR_ERR(filp);
316 goto out;
319 autofs_dev_ioctl_fd_install(fd, filp);
322 return fd;
324 out:
325 put_unused_fd(fd);
326 return err;
329 /* Open a file descriptor on an autofs mount point */
330 static int autofs_dev_ioctl_openmount(struct file *fp,
331 struct autofs_sb_info *sbi,
332 struct autofs_dev_ioctl *param)
334 const char *path;
335 dev_t devid;
336 int err, fd;
338 /* param->path has already been checked */
339 if (!param->openmount.devid)
340 return -EINVAL;
342 param->ioctlfd = -1;
344 path = param->path;
345 devid = param->openmount.devid;
347 err = 0;
348 fd = autofs_dev_ioctl_open_mountpoint(path, devid);
349 if (unlikely(fd < 0)) {
350 err = fd;
351 goto out;
354 param->ioctlfd = fd;
355 out:
356 return err;
359 /* Close file descriptor allocated above (user can also use close(2)). */
360 static int autofs_dev_ioctl_closemount(struct file *fp,
361 struct autofs_sb_info *sbi,
362 struct autofs_dev_ioctl *param)
364 return sys_close(param->ioctlfd);
368 * Send "ready" status for an existing wait (either a mount or an expire
369 * request).
371 static int autofs_dev_ioctl_ready(struct file *fp,
372 struct autofs_sb_info *sbi,
373 struct autofs_dev_ioctl *param)
375 autofs_wqt_t token;
377 token = (autofs_wqt_t) param->ready.token;
378 return autofs4_wait_release(sbi, token, 0);
382 * Send "fail" status for an existing wait (either a mount or an expire
383 * request).
385 static int autofs_dev_ioctl_fail(struct file *fp,
386 struct autofs_sb_info *sbi,
387 struct autofs_dev_ioctl *param)
389 autofs_wqt_t token;
390 int status;
392 token = (autofs_wqt_t) param->fail.token;
393 status = param->fail.status ? param->fail.status : -ENOENT;
394 return autofs4_wait_release(sbi, token, status);
398 * Set the pipe fd for kernel communication to the daemon.
400 * Normally this is set at mount using an option but if we
401 * are reconnecting to a busy mount then we need to use this
402 * to tell the autofs mount about the new kernel pipe fd. In
403 * order to protect mounts against incorrectly setting the
404 * pipefd we also require that the autofs mount be catatonic.
406 * This also sets the process group id used to identify the
407 * controlling process (eg. the owning automount(8) daemon).
409 static int autofs_dev_ioctl_setpipefd(struct file *fp,
410 struct autofs_sb_info *sbi,
411 struct autofs_dev_ioctl *param)
413 int pipefd;
414 int err = 0;
416 if (param->setpipefd.pipefd == -1)
417 return -EINVAL;
419 pipefd = param->setpipefd.pipefd;
421 mutex_lock(&sbi->wq_mutex);
422 if (!sbi->catatonic) {
423 mutex_unlock(&sbi->wq_mutex);
424 return -EBUSY;
425 } else {
426 struct file *pipe = fget(pipefd);
427 if (!pipe->f_op || !pipe->f_op->write) {
428 err = -EPIPE;
429 fput(pipe);
430 goto out;
432 sbi->oz_pgrp = task_pgrp_nr(current);
433 sbi->pipefd = pipefd;
434 sbi->pipe = pipe;
435 sbi->catatonic = 0;
437 out:
438 mutex_unlock(&sbi->wq_mutex);
439 return err;
443 * Make the autofs mount point catatonic, no longer responsive to
444 * mount requests. Also closes the kernel pipe file descriptor.
446 static int autofs_dev_ioctl_catatonic(struct file *fp,
447 struct autofs_sb_info *sbi,
448 struct autofs_dev_ioctl *param)
450 autofs4_catatonic_mode(sbi);
451 return 0;
454 /* Set the autofs mount timeout */
455 static int autofs_dev_ioctl_timeout(struct file *fp,
456 struct autofs_sb_info *sbi,
457 struct autofs_dev_ioctl *param)
459 unsigned long timeout;
461 timeout = param->timeout.timeout;
462 param->timeout.timeout = sbi->exp_timeout / HZ;
463 sbi->exp_timeout = timeout * HZ;
464 return 0;
468 * Return the uid and gid of the last request for the mount
470 * When reconstructing an autofs mount tree with active mounts
471 * we need to re-connect to mounts that may have used the original
472 * process uid and gid (or string variations of them) for mount
473 * lookups within the map entry.
475 static int autofs_dev_ioctl_requester(struct file *fp,
476 struct autofs_sb_info *sbi,
477 struct autofs_dev_ioctl *param)
479 struct autofs_info *ino;
480 struct nameidata nd;
481 const char *path;
482 dev_t devid;
483 int err = -ENOENT;
485 if (param->size <= sizeof(*param)) {
486 err = -EINVAL;
487 goto out;
490 path = param->path;
491 devid = sbi->sb->s_dev;
493 param->requester.uid = param->requester.gid = -1;
495 /* Get nameidata of the parent directory */
496 err = path_lookup(path, LOOKUP_PARENT, &nd);
497 if (err)
498 goto out;
500 err = autofs_dev_ioctl_find_super(&nd, devid);
501 if (err)
502 goto out_release;
504 ino = autofs4_dentry_ino(nd.path.dentry);
505 if (ino) {
506 err = 0;
507 autofs4_expire_wait(nd.path.dentry);
508 spin_lock(&sbi->fs_lock);
509 param->requester.uid = ino->uid;
510 param->requester.gid = ino->gid;
511 spin_unlock(&sbi->fs_lock);
514 out_release:
515 path_put(&nd.path);
516 out:
517 return err;
521 * Call repeatedly until it returns -EAGAIN, meaning there's nothing
522 * more that can be done.
524 static int autofs_dev_ioctl_expire(struct file *fp,
525 struct autofs_sb_info *sbi,
526 struct autofs_dev_ioctl *param)
528 struct vfsmount *mnt;
529 int how;
531 how = param->expire.how;
532 mnt = fp->f_path.mnt;
534 return autofs4_do_expire_multi(sbi->sb, mnt, sbi, how);
537 /* Check if autofs mount point is in use */
538 static int autofs_dev_ioctl_askumount(struct file *fp,
539 struct autofs_sb_info *sbi,
540 struct autofs_dev_ioctl *param)
542 param->askumount.may_umount = 0;
543 if (may_umount(fp->f_path.mnt))
544 param->askumount.may_umount = 1;
545 return 0;
549 * Check if the given path is a mountpoint.
551 * If we are supplied with the file descriptor of an autofs
552 * mount we're looking for a specific mount. In this case
553 * the path is considered a mountpoint if it is itself a
554 * mountpoint or contains a mount, such as a multi-mount
555 * without a root mount. In this case we return 1 if the
556 * path is a mount point and the super magic of the covering
557 * mount if there is one or 0 if it isn't a mountpoint.
559 * If we aren't supplied with a file descriptor then we
560 * lookup the nameidata of the path and check if it is the
561 * root of a mount. If a type is given we are looking for
562 * a particular autofs mount and if we don't find a match
563 * we return fail. If the located nameidata path is the
564 * root of a mount we return 1 along with the super magic
565 * of the mount or 0 otherwise.
567 * In both cases the the device number (as returned by
568 * new_encode_dev()) is also returned.
570 static int autofs_dev_ioctl_ismountpoint(struct file *fp,
571 struct autofs_sb_info *sbi,
572 struct autofs_dev_ioctl *param)
574 struct nameidata nd;
575 const char *path;
576 unsigned int type;
577 unsigned int devid, magic;
578 int err = -ENOENT;
580 if (param->size <= sizeof(*param)) {
581 err = -EINVAL;
582 goto out;
585 path = param->path;
586 type = param->ismountpoint.in.type;
588 param->ismountpoint.out.devid = devid = 0;
589 param->ismountpoint.out.magic = magic = 0;
591 if (!fp || param->ioctlfd == -1) {
592 if (autofs_type_any(type)) {
593 struct super_block *sb;
595 err = path_lookup(path, LOOKUP_FOLLOW, &nd);
596 if (err)
597 goto out;
599 sb = nd.path.dentry->d_sb;
600 devid = new_encode_dev(sb->s_dev);
601 } else {
602 struct autofs_info *ino;
604 err = path_lookup(path, LOOKUP_PARENT, &nd);
605 if (err)
606 goto out;
608 err = autofs_dev_ioctl_find_sbi_type(&nd, type);
609 if (err)
610 goto out_release;
612 ino = autofs4_dentry_ino(nd.path.dentry);
613 devid = autofs4_get_dev(ino->sbi);
616 err = 0;
617 if (nd.path.dentry->d_inode &&
618 nd.path.mnt->mnt_root == nd.path.dentry) {
619 err = 1;
620 magic = nd.path.dentry->d_inode->i_sb->s_magic;
622 } else {
623 dev_t dev = autofs4_get_dev(sbi);
625 err = path_lookup(path, LOOKUP_PARENT, &nd);
626 if (err)
627 goto out;
629 err = autofs_dev_ioctl_find_super(&nd, dev);
630 if (err)
631 goto out_release;
633 devid = dev;
635 err = have_submounts(nd.path.dentry);
637 if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
638 if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
639 struct inode *inode = nd.path.dentry->d_inode;
640 magic = inode->i_sb->s_magic;
645 param->ismountpoint.out.devid = devid;
646 param->ismountpoint.out.magic = magic;
648 out_release:
649 path_put(&nd.path);
650 out:
651 return err;
655 * Our range of ioctl numbers isn't 0 based so we need to shift
656 * the array index by _IOC_NR(AUTOFS_CTL_IOC_FIRST) for the table
657 * lookup.
659 #define cmd_idx(cmd) (cmd - _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST))
661 static ioctl_fn lookup_dev_ioctl(unsigned int cmd)
663 static struct {
664 int cmd;
665 ioctl_fn fn;
666 } _ioctls[] = {
667 {cmd_idx(AUTOFS_DEV_IOCTL_VERSION_CMD), NULL},
668 {cmd_idx(AUTOFS_DEV_IOCTL_PROTOVER_CMD),
669 autofs_dev_ioctl_protover},
670 {cmd_idx(AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD),
671 autofs_dev_ioctl_protosubver},
672 {cmd_idx(AUTOFS_DEV_IOCTL_OPENMOUNT_CMD),
673 autofs_dev_ioctl_openmount},
674 {cmd_idx(AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD),
675 autofs_dev_ioctl_closemount},
676 {cmd_idx(AUTOFS_DEV_IOCTL_READY_CMD),
677 autofs_dev_ioctl_ready},
678 {cmd_idx(AUTOFS_DEV_IOCTL_FAIL_CMD),
679 autofs_dev_ioctl_fail},
680 {cmd_idx(AUTOFS_DEV_IOCTL_SETPIPEFD_CMD),
681 autofs_dev_ioctl_setpipefd},
682 {cmd_idx(AUTOFS_DEV_IOCTL_CATATONIC_CMD),
683 autofs_dev_ioctl_catatonic},
684 {cmd_idx(AUTOFS_DEV_IOCTL_TIMEOUT_CMD),
685 autofs_dev_ioctl_timeout},
686 {cmd_idx(AUTOFS_DEV_IOCTL_REQUESTER_CMD),
687 autofs_dev_ioctl_requester},
688 {cmd_idx(AUTOFS_DEV_IOCTL_EXPIRE_CMD),
689 autofs_dev_ioctl_expire},
690 {cmd_idx(AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD),
691 autofs_dev_ioctl_askumount},
692 {cmd_idx(AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD),
693 autofs_dev_ioctl_ismountpoint}
695 unsigned int idx = cmd_idx(cmd);
697 return (idx >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[idx].fn;
700 /* ioctl dispatcher */
701 static int _autofs_dev_ioctl(unsigned int command, struct autofs_dev_ioctl __user *user)
703 struct autofs_dev_ioctl *param;
704 struct file *fp;
705 struct autofs_sb_info *sbi;
706 unsigned int cmd_first, cmd;
707 ioctl_fn fn = NULL;
708 int err = 0;
710 /* only root can play with this */
711 if (!capable(CAP_SYS_ADMIN))
712 return -EPERM;
714 cmd_first = _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST);
715 cmd = _IOC_NR(command);
717 if (_IOC_TYPE(command) != _IOC_TYPE(AUTOFS_DEV_IOCTL_IOC_FIRST) ||
718 cmd - cmd_first >= AUTOFS_DEV_IOCTL_IOC_COUNT) {
719 return -ENOTTY;
722 /* Copy the parameters into kernel space. */
723 param = copy_dev_ioctl(user);
724 if (IS_ERR(param))
725 return PTR_ERR(param);
727 err = validate_dev_ioctl(command, param);
728 if (err)
729 goto out;
731 /* The validate routine above always sets the version */
732 if (cmd == AUTOFS_DEV_IOCTL_VERSION_CMD)
733 goto done;
735 fn = lookup_dev_ioctl(cmd);
736 if (!fn) {
737 AUTOFS_WARN("unknown command 0x%08x", command);
738 return -ENOTTY;
741 fp = NULL;
742 sbi = NULL;
745 * For obvious reasons the openmount can't have a file
746 * descriptor yet. We don't take a reference to the
747 * file during close to allow for immediate release.
749 if (cmd != AUTOFS_DEV_IOCTL_OPENMOUNT_CMD &&
750 cmd != AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD) {
751 fp = fget(param->ioctlfd);
752 if (!fp) {
753 if (cmd == AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD)
754 goto cont;
755 err = -EBADF;
756 goto out;
759 if (!fp->f_op) {
760 err = -ENOTTY;
761 fput(fp);
762 goto out;
765 sbi = autofs_dev_ioctl_sbi(fp);
766 if (!sbi || sbi->magic != AUTOFS_SBI_MAGIC) {
767 err = -EINVAL;
768 fput(fp);
769 goto out;
773 * Admin needs to be able to set the mount catatonic in
774 * order to be able to perform the re-open.
776 if (!autofs4_oz_mode(sbi) &&
777 cmd != AUTOFS_DEV_IOCTL_CATATONIC_CMD) {
778 err = -EACCES;
779 fput(fp);
780 goto out;
783 cont:
784 err = fn(fp, sbi, param);
786 if (fp)
787 fput(fp);
788 done:
789 if (err >= 0 && copy_to_user(user, param, AUTOFS_DEV_IOCTL_SIZE))
790 err = -EFAULT;
791 out:
792 free_dev_ioctl(param);
793 return err;
796 static long autofs_dev_ioctl(struct file *file, uint command, ulong u)
798 int err;
799 err = _autofs_dev_ioctl(command, (struct autofs_dev_ioctl __user *) u);
800 return (long) err;
803 #ifdef CONFIG_COMPAT
804 static long autofs_dev_ioctl_compat(struct file *file, uint command, ulong u)
806 return (long) autofs_dev_ioctl(file, command, (ulong) compat_ptr(u));
808 #else
809 #define autofs_dev_ioctl_compat NULL
810 #endif
812 static const struct file_operations _dev_ioctl_fops = {
813 .unlocked_ioctl = autofs_dev_ioctl,
814 .compat_ioctl = autofs_dev_ioctl_compat,
815 .owner = THIS_MODULE,
818 static struct miscdevice _autofs_dev_ioctl_misc = {
819 .minor = MISC_DYNAMIC_MINOR,
820 .name = AUTOFS_DEVICE_NAME,
821 .fops = &_dev_ioctl_fops
824 /* Register/deregister misc character device */
825 int autofs_dev_ioctl_init(void)
827 int r;
829 r = misc_register(&_autofs_dev_ioctl_misc);
830 if (r) {
831 AUTOFS_ERROR("misc_register failed for control device");
832 return r;
835 return 0;
838 void autofs_dev_ioctl_exit(void)
840 misc_deregister(&_autofs_dev_ioctl_misc);
841 return;