[PATCH 4/4] autofs4 - add miscelaneous device for ioctls
From: Ian Kent
Date: Mon Feb 25 2008 - 22:26:50 EST
Hi Andrew,
Patch to add miscellaneous device to autofs4 module for
ioctls.
Signed-off-by: Ian Kent < raven@xxxxxxxxxx>
Ian
---
diff -up linux-2.6.25-rc2-mm1/fs/autofs4/expire.c.device-node-ioctl linux-2.6.25-rc2-mm1/fs/autofs4/expire.c
--- linux-2.6.25-rc2-mm1/fs/autofs4/expire.c.device-node-ioctl 2008-01-25 07:58:37.000000000 +0900
+++ linux-2.6.25-rc2-mm1/fs/autofs4/expire.c 2008-02-22 11:51:41.000000000 +0900
@@ -244,10 +244,10 @@ cont:
}
/* Check if we can expire a direct mount (possibly a tree) */
-static struct dentry *autofs4_expire_direct(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- int how)
+struct dentry *autofs4_expire_direct(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ int how)
{
unsigned long timeout;
struct dentry *root = dget(sb->s_root);
@@ -281,10 +281,10 @@ static struct dentry *autofs4_expire_dir
* - it is unused by any user process
* - it has been unused for exp_timeout time
*/
-static struct dentry *autofs4_expire_indirect(struct super_block *sb,
- struct vfsmount *mnt,
- struct autofs_sb_info *sbi,
- int how)
+struct dentry *autofs4_expire_indirect(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi,
+ int how)
{
unsigned long timeout;
struct dentry *root = sb->s_root;
diff -up linux-2.6.25-rc2-mm1/fs/autofs4/init.c.device-node-ioctl linux-2.6.25-rc2-mm1/fs/autofs4/init.c
--- linux-2.6.25-rc2-mm1/fs/autofs4/init.c.device-node-ioctl 2008-01-25 07:58:37.000000000 +0900
+++ linux-2.6.25-rc2-mm1/fs/autofs4/init.c 2008-02-22 11:51:41.000000000 +0900
@@ -29,11 +29,20 @@ static struct file_system_type autofs_fs
static int __init init_autofs4_fs(void)
{
- return register_filesystem(&autofs_fs_type);
+ int err;
+
+ err = register_filesystem(&autofs_fs_type);
+ if (err)
+ return err;
+
+ err = autofs_dev_ioctl_init();
+
+ return err;
}
static void __exit exit_autofs4_fs(void)
{
+ autofs_dev_ioctl_exit();
unregister_filesystem(&autofs_fs_type);
}
diff -up linux-2.6.25-rc2-mm1/fs/autofs4/autofs_i.h.device-node-ioctl linux-2.6.25-rc2-mm1/fs/autofs4/autofs_i.h
--- linux-2.6.25-rc2-mm1/fs/autofs4/autofs_i.h.device-node-ioctl 2008-02-22 11:51:41.000000000 +0900
+++ linux-2.6.25-rc2-mm1/fs/autofs4/autofs_i.h 2008-02-22 11:51:41.000000000 +0900
@@ -14,6 +14,7 @@
/* Internal header file for autofs */
#include <linux/auto_fs4.h>
+#include <linux/auto_dev-ioctl.h>
#include <linux/mutex.h>
#include <linux/list.h>
@@ -40,6 +41,16 @@
#define DPRINTK(fmt,args...) do {} while(0)
#endif
+#define WARN(fmt,args...) \
+do { \
+ printk("KERN_WARNING pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); \
+} while(0)
+
+#define ERROR(fmt,args...) \
+do { \
+ printk("KERN_ERR pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); \
+} while(0)
+
/* Unified info structure. This is pointed to by both the dentry and
inode structures. Each file in the filesystem has an instance of this
structure. It holds a reference to the dentry, so dentries are never
@@ -172,6 +183,17 @@ int autofs4_expire_run(struct super_bloc
struct autofs_packet_expire __user *);
int autofs4_expire_multi(struct super_block *, struct vfsmount *,
struct autofs_sb_info *, int __user *);
+struct dentry *autofs4_expire_direct(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi, int how);
+struct dentry *autofs4_expire_indirect(struct super_block *sb,
+ struct vfsmount *mnt,
+ struct autofs_sb_info *sbi, int how);
+
+/* Device node initialization */
+
+int autofs_dev_ioctl_init(void);
+void autofs_dev_ioctl_exit(void);
/* Operations structures */
diff -up linux-2.6.25-rc2-mm1/fs/autofs4/Makefile.device-node-ioctl linux-2.6.25-rc2-mm1/fs/autofs4/Makefile
--- linux-2.6.25-rc2-mm1/fs/autofs4/Makefile.device-node-ioctl 2008-01-25 07:58:37.000000000 +0900
+++ linux-2.6.25-rc2-mm1/fs/autofs4/Makefile 2008-02-22 11:51:41.000000000 +0900
@@ -4,4 +4,4 @@
obj-$(CONFIG_AUTOFS4_FS) += autofs4.o
-autofs4-objs := init.o inode.o root.o symlink.o waitq.o expire.o
+autofs4-objs := init.o inode.o root.o symlink.o waitq.o expire.o dev-ioctl.o
diff -up /dev/null linux-2.6.25-rc2-mm1/fs/autofs4/dev-ioctl.c
--- /dev/null 2008-02-22 18:55:57.149000956 +0900
+++ linux-2.6.25-rc2-mm1/fs/autofs4/dev-ioctl.c 2008-02-22 11:53:33.000000000 +0900
@@ -0,0 +1,788 @@
+/*
+ * linux/fs/autofs4/dev-ioctl.c
+ *
+ * Copyright 2008 Red Hat, Inc. All rights reserved.
+ * Copyright 2008 Ian Kent <raven@xxxxxxxxxx>
+ *
+ * This file is part of the Linux kernel and is made available under
+ * the terms of the GNU General Public License, version 2, or at your
+ * option, any later version, incorporated herein by reference.
+ */
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/wait.h>
+#include <linux/namei.h>
+#include <linux/fcntl.h>
+#include <linux/file.h>
+#include <linux/sched.h>
+#include <linux/compat.h>
+#include <linux/syscalls.h>
+#include <linux/smp_lock.h>
+#include <linux/magic.h>
+#include <linux/dcache.h>
+#include <asm/uaccess.h>
+
+#include "autofs_i.h"
+
+/*
+ * This module implements an interface for routing autofs ioctl control
+ * commands via a miscellaneous device file.
+ *
+ * The alternate interface is needed because we need to be able open
+ * an ioctl file descriptor on an autofs mount that may be covered by
+ * another mount. This situation arises when starting automount(8)
+ * or other user space daemon which uses direct mounts or offset
+ * mounts (used for autofs lazy mount/umount of nested mount trees),
+ * which have been left busy at at service shutdown.
+ */
+
+#define AUTOFS_DEVICE_NAME "autofs"
+
+#define AUTOFS_DEV_IOCTL_IOC_FIRST AUTOFS_DEV_IOCTL_VERSION
+#define AUTOFS_DEV_IOCTL_IOC_COUNT AUTOFS_IOC_COUNT - 11
+
+#define AUTOFS_DEV_IOCTL_SIZE sizeof(struct autofs_dev_ioctl)
+
+typedef int (*ioctl_fn)(struct file *, struct autofs_sb_info *, struct autofs_dev_ioctl *);
+
+static int check_name(const char *name)
+{
+ if (!strchr(name, '/'))
+ return -EINVAL;
+ return 0;
+}
+
+/*
+ * Check a string doesn't overrun the chunk of
+ * memory we copied from user land.
+ */
+static int invalid_str(char *str, void *end)
+{
+ while ((void *) str <= end)
+ if (!*str++)
+ return 0;
+ return -EINVAL;
+}
+
+/*
+ * Check that the user compiled against correct version of autofs
+ * misc device code.
+ *
+ * As well as checking the version compatibility this always copies
+ * the kernel interface version out.
+ */
+static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
+{
+ int err = 0;
+
+ if ((AUTOFS_DEV_IOCTL_VERSION_MAJOR != param->ver_major) ||
+ (AUTOFS_DEV_IOCTL_VERSION_MINOR < param->ver_minor)) {
+ WARN("ioctl control interface version mismatch: "
+ "kernel(%u.%u), user(%u.%u), cmd(%d)",
+ AUTOFS_DEV_IOCTL_VERSION_MAJOR,
+ AUTOFS_DEV_IOCTL_VERSION_MINOR,
+ param->ver_major, param->ver_minor, cmd);
+ err = -EINVAL;
+ }
+
+ /* Fill in the kernel version. */
+ param->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
+ param->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
+
+ return err;
+}
+
+/*
+ * Copy parameter control struct, including a possible path allocated
+ * at the end of the struct.
+ */
+static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in)
+{
+ struct autofs_dev_ioctl tmp, *ads;
+
+ if (copy_from_user(&tmp, in, sizeof(tmp)))
+ return ERR_PTR(-EFAULT);
+
+ if (tmp.size < sizeof(tmp))
+ return ERR_PTR(-EINVAL);
+
+ ads = kmalloc(tmp.size, GFP_KERNEL);
+ if (!ads)
+ return ERR_PTR(-ENOMEM);
+
+ if (copy_from_user(ads, in, tmp.size)) {
+ vfree(ads);
+ return ERR_PTR(-EFAULT);
+ }
+
+ return ads;
+}
+
+static inline void free_dev_ioctl(struct autofs_dev_ioctl *param)
+{
+ kfree(param);
+ return;
+}
+
+/*
+ * Check sanity of parameter control fields and if a path is present
+ * check that it has a "/" and is terminated.
+ */
+static int validate_dev_ioctl(int cmd, struct autofs_dev_ioctl *param)
+{
+ int err = -EINVAL;
+
+ if (check_dev_ioctl_version(cmd, param)) {
+ WARN("invalid device control module version "
+ "supplied for cmd(0x%08x)", cmd);
+ goto out;
+ }
+
+ if (param->size > sizeof(*param)) {
+ err = check_name(param->path);
+ if (err) {
+ WARN("invalid path supplied for cmd(0x%08x)", cmd);
+ goto out;
+ }
+
+ err = invalid_str(param->path,
+ (void *) ((size_t) param + param->size));
+ if (err) {
+ WARN("invalid path supplied for cmd(0x%08x)", cmd);
+ goto out;
+ }
+ }
+
+ err = 0;
+out:
+ return err;
+}
+
+/*
+ * Get the autofs super block info struct from the file opened on
+ * the autofs mount point.
+ */
+static struct autofs_sb_info *autofs_dev_ioctl_sbi(struct file *f)
+{
+ struct autofs_sb_info *sbi = NULL;
+ struct inode *inode;
+
+ if (f) {
+ inode = f->f_path.dentry->d_inode;
+ sbi = autofs4_sbi(inode->i_sb);
+ }
+
+ return sbi;
+}
+
+/* Return autofs module protocol version */
+static inline int autofs_dev_ioctl_protover(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ param->arg1 = sbi->version;
+ return 0;
+}
+
+/* Return autofs module protocol sub version */
+static inline int autofs_dev_ioctl_protosubver(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ param->arg1 = sbi->sub_version;
+ return 0;
+}
+
+/*
+ * Walk down the mount stack looking for an autofs mount that
+ * has the requested device number (aka. new_encode_dev(sb->s_dev).
+ */
+static int autofs_dev_ioctl_find_super(struct nameidata *nd, dev_t devno)
+{
+ struct dentry *dentry;
+ struct inode *inode;
+ struct super_block *sb;
+ dev_t s_dev;
+ unsigned int err;
+
+ err = -ENOENT;
+
+ /* Lookup the dentry name at the base of our mount point */
+ dentry = d_lookup(nd->path.dentry, &nd->last);
+ if (!dentry)
+ goto out;
+
+ dput(nd->path.dentry);
+ nd->path.dentry = dentry;
+
+ /* And follow the mount stack looking for our autofs mount */
+ while (1) {
+ inode = nd->path.dentry->d_inode;
+ if (!inode)
+ continue;
+
+ sb = inode->i_sb;
+ s_dev = new_encode_dev(sb->s_dev);
+ if (devno == s_dev) {
+ if (sb->s_magic == AUTOFS_SUPER_MAGIC) {
+ err = 0;
+ break;
+ }
+ }
+
+ if (!follow_down(&nd->path.mnt, &nd->path.dentry))
+ goto out;
+ }
+
+out:
+ return err;
+}
+
+/*
+ * Install the file opened for autofs mount point control functions
+ * and set close on exec.
+ */
+static void autofs_dev_ioctl_fd_install(unsigned int fd, struct file *file)
+{
+ struct files_struct *files = current->files;
+ struct fdtable *fdt;
+
+ spin_lock(&files->file_lock);
+ fdt = files_fdtable(files);
+ BUG_ON(fdt->fd[fd] != NULL);
+ rcu_assign_pointer(fdt->fd[fd], file);
+ FD_SET(fd, fdt->close_on_exec);
+ spin_unlock(&files->file_lock);
+}
+
+/*
+ * Open a file descriptor on the autofs mount point corresponding
+ * to the given path and device number (aka. new_encode_dev(sb->s_dev)).
+ */
+static int autofs_dev_ioctl_open_mountpoint(const char *path, dev_t devid)
+{
+ struct file *filp;
+ struct nameidata nd;
+ int err, fd;
+
+ fd = get_unused_fd();
+ if (fd >= 0) {
+ /* Get nameidata of the parent directory */
+ err = path_lookup(path, LOOKUP_PARENT, &nd);
+ if (err)
+ goto out;
+
+ /*
+ * Search down, within the parent, looking for an
+ * autofs super block that has the device number
+ * corresponding to the autofs fs we want to open.
+ */
+ err = autofs_dev_ioctl_find_super(&nd, devid);
+ if (err)
+ goto out_put;
+
+ filp = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY);
+ if (IS_ERR(filp)) {
+ err = PTR_ERR(filp);
+ goto out_put;
+ }
+
+ autofs_dev_ioctl_fd_install(fd, filp);
+ }
+
+ return fd;
+
+out_put:
+ path_put(&nd.path);
+out:
+ put_unused_fd(fd);
+ return err;
+}
+
+/* Open a file descriptor on an autofs mount point */
+static int autofs_dev_ioctl_openmount(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ const char *path;
+ dev_t devid;
+ int err, fd;
+
+ /* param->path has already been checked */
+ if (!param->arg1)
+ return -EINVAL;
+
+ err = 0;
+
+ devid = param->arg1;
+ path = param->path;
+
+ fd = autofs_dev_ioctl_open_mountpoint(path, devid);
+ if (fd < 0) {
+ err = fd;
+ goto out;
+ }
+
+ param->ioctlfd = fd;
+out:
+ return err;
+}
+
+/* Close file descriptor allocated above (user can also use close(2)). */
+static inline int autofs_dev_ioctl_closemount(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ return sys_close(param->ioctlfd);
+}
+
+/*
+ * Send "ready" status for an existing wait (either a mount or an expire
+ * request).
+ */
+static inline int autofs_dev_ioctl_ready(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ autofs_wqt_t token;
+
+ token = (autofs_wqt_t) param->arg1;
+ return autofs4_wait_release(sbi, token, 0);
+}
+
+/*
+ * Send "fail" status for an existing wait (either a mount or an expire
+ * request).
+ */
+static inline int autofs_dev_ioctl_fail(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ autofs_wqt_t token;
+ int status;
+
+ token = (autofs_wqt_t) param->arg1;
+ status = param->arg2 ? param->arg2 : -ENOENT;
+ return autofs4_wait_release(sbi, token, status);
+}
+
+/*
+ * Set the pipe fd for kernel communication to the daemon.
+ *
+ * Normally this is set at mount using an option but if we
+ * are reconnecting to a busy mount then we need to use this
+ * to tell the autofs mount about the new kernel pipe fd. In
+ * order to protect mounts against incorrectly setting the
+ * pipefd we also require that the autofs mount be catatonic.
+ *
+ * This also sets the process group id used to identify the
+ * controlling process (eg. the owning automount(8) daemon).
+ */
+static int autofs_dev_ioctl_setpipefd(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ int pipefd;
+ int err = 0;
+
+ if (param->arg1 == -1)
+ return -EINVAL;
+
+ pipefd = param->arg1;
+
+ if (!sbi->catatonic)
+ return -EBUSY;
+ else {
+ struct file *pipe = fget(pipefd);
+ if (!pipe->f_op || !pipe->f_op->write) {
+ err = -EPIPE;
+ fput(pipe);
+ goto out;
+ }
+ sbi->oz_pgrp = task_pgrp_nr(current);
+ sbi->pipefd = pipefd;
+ sbi->pipe = pipe;
+ sbi->catatonic = 0;
+ }
+out:
+ return err;
+}
+
+/*
+ * Make the autofs mount point catatonic, no longer responsive to
+ * mount requests. Also closes the kernel pipe file descriptor.
+ */
+static inline int autofs_dev_ioctl_catatonic(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ if (!sbi->catatonic)
+ autofs4_catatonic_mode(sbi);
+ return 0;
+}
+
+/* Set the autofs mount timeout */
+static inline int autofs_dev_ioctl_timeout(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ unsigned long timeout;
+
+ timeout = param->arg1;
+ param->arg1 = sbi->exp_timeout / HZ;
+ sbi->exp_timeout = timeout * HZ;
+ return 0;
+}
+
+/*
+ * Return the uid and gid of the last request for the mount
+ *
+ * When reconstructing an autofs mount tree with active mounts
+ * we need to re-connect to mounts that may have used the original
+ * process uid and gid (or string variations of them) for mount
+ * lookups within the map entry.
+ */
+static inline int autofs_dev_ioctl_requestor(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ struct autofs_info *ino;
+ struct nameidata nd;
+ const char *path;
+ dev_t devid;
+ int err = -ENOENT;
+
+ if (param->size <= sizeof(*param)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ path = param->path;
+ devid = sbi->sb->s_dev;
+
+ param->arg1 = param->arg2 = -1;
+
+ /* Get nameidata of the parent directory */
+ err = path_lookup(path, LOOKUP_PARENT, &nd);
+ if (err)
+ goto out;
+
+ err = autofs_dev_ioctl_find_super(&nd, devid);
+ if (err)
+ goto out_release;
+
+ ino = autofs4_dentry_ino(nd.path.dentry);
+ if (ino) {
+ err = 0;
+ param->arg1 = ino->uid;
+ param->arg2 = ino->gid;
+ }
+
+out_release:
+ path_put(&nd.path);
+out:
+ return err;
+}
+
+/*
+ * Call repeatedly until it returns -EAGAIN, meaning there's nothing
+ * more that can be done.
+ */
+static int autofs_dev_ioctl_expire(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ struct dentry *dentry;
+ struct vfsmount *mnt;
+ int err = -EAGAIN;
+ int when;
+
+ when = param->arg1;
+ mnt = fp->f_path.mnt;
+
+ if (sbi->type & AUTOFS_TYPE_DIRECT)
+ dentry = autofs4_expire_direct(sbi->sb, mnt, sbi, when);
+ else
+ dentry = autofs4_expire_indirect(sbi->sb, mnt, sbi, when);
+
+ if (dentry) {
+ struct autofs_info *ino = autofs4_dentry_ino(dentry);
+
+ /*
+ * This is synchronous because it makes the daemon a
+ * little easier
+ */
+ ino->flags |= AUTOFS_INF_EXPIRING;
+ err = autofs4_wait(sbi, dentry, NFY_EXPIRE);
+ ino->flags &= ~AUTOFS_INF_EXPIRING;
+ dput(dentry);
+ }
+
+ return err;
+}
+
+/* Check if autofs mount point is in use */
+static inline int autofs_dev_ioctl_askumount(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ param->arg1 = 0;
+ if (may_umount(fp->f_path.mnt))
+ param->arg1 = 1;
+ return 0;
+}
+
+/*
+ * Check if the given path is a mountpoint.
+ *
+ * If we are supplied with the file descriptor of the autofs
+ * mount we're looking for a specific mount. In this case
+ * the path is considered a mountpoint if it is itself a
+ * mountpoint or contains a mount, such as a multi-mount
+ * without a root mount.
+ *
+ * If we aren't supplied with a file descriptor then we lookup
+ * the nameidata of the path and check if is a mounted autofs
+ * filesystem or a filesystem mounted within an autofs filesystem.
+ *
+ * In both cases we return an indication of whether the path
+ * is a mount point and the super magic of the covering mount.
+ */
+static inline int autofs_dev_ioctl_ismountpoint(struct file *fp,
+ struct autofs_sb_info *sbi,
+ struct autofs_dev_ioctl *param)
+{
+ struct nameidata nd;
+ const char *path;
+ int err = -ENOENT;
+
+ if (param->size <= sizeof(*param)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ path = param->path;
+
+ param->arg1 = param->arg2 = 0;
+
+ if (param->ioctlfd == -1) {
+ unsigned long magic;
+
+ err = path_lookup(path, LOOKUP_FOLLOW, &nd);
+ if (err)
+ goto out;
+
+ magic = nd.path.dentry->d_inode->i_sb->s_magic;
+
+ if (follow_up(&nd.path.mnt, &nd.path.dentry)) {
+ struct inode *inode = nd.path.dentry->d_inode;
+ if (magic == AUTOFS_SUPER_MAGIC ||
+ inode->i_sb->s_magic == AUTOFS_SUPER_MAGIC) {
+ param->arg1 = 1;
+ param->arg2 = magic;
+ }
+ }
+ } else {
+ dev_t devid = sbi->sb->s_dev;
+
+ err = path_lookup(path, LOOKUP_PARENT, &nd);
+ if (err)
+ goto out;
+
+ err = autofs_dev_ioctl_find_super(&nd, devid);
+ if (err)
+ goto out_release;
+
+ param->arg1 = have_submounts(nd.path.dentry);
+
+ if (d_mountpoint(nd.path.dentry)) {
+ if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
+ struct inode *inode = nd.path.dentry->d_inode;
+ param->arg2 = inode->i_sb->s_magic;
+ }
+ }
+ }
+
+out_release:
+ path_put(&nd.path);
+out:
+ return err;
+}
+
+/*
+ * Our range of ioctl numbers isn't 0 based so we need to shift
+ * the array index by _IOC_NR(AUTOFS_CTL_IOC_FIRST) for the table
+ * lookup.
+ */
+#define cmd_idx(cmd) (cmd - _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST))
+
+static ioctl_fn lookup_dev_ioctl(unsigned int cmd)
+{
+ static struct {
+ int cmd;
+ ioctl_fn fn;
+ } _ioctls[] = {
+ {cmd_idx(AUTOFS_DEV_IOCTL_VERSION_CMD), NULL},
+ {cmd_idx(AUTOFS_DEV_IOCTL_PROTOVER_CMD), autofs_dev_ioctl_protover},
+ {cmd_idx(AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD), autofs_dev_ioctl_protosubver},
+ {cmd_idx(AUTOFS_DEV_IOCTL_OPENMOUNT_CMD), autofs_dev_ioctl_openmount},
+ {cmd_idx(AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD), autofs_dev_ioctl_closemount},
+ {cmd_idx(AUTOFS_DEV_IOCTL_READY_CMD), autofs_dev_ioctl_ready},
+ {cmd_idx(AUTOFS_DEV_IOCTL_FAIL_CMD), autofs_dev_ioctl_fail},
+ {cmd_idx(AUTOFS_DEV_IOCTL_SETPIPEFD_CMD), autofs_dev_ioctl_setpipefd},
+ {cmd_idx(AUTOFS_DEV_IOCTL_CATATONIC_CMD), autofs_dev_ioctl_catatonic},
+ {cmd_idx(AUTOFS_DEV_IOCTL_TIMEOUT_CMD), autofs_dev_ioctl_timeout},
+ {cmd_idx(AUTOFS_DEV_IOCTL_REQUESTOR_CMD), autofs_dev_ioctl_requestor},
+ {cmd_idx(AUTOFS_DEV_IOCTL_EXPIRE_CMD), autofs_dev_ioctl_expire},
+ {cmd_idx(AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD), autofs_dev_ioctl_askumount},
+ {cmd_idx(AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD), autofs_dev_ioctl_ismountpoint}
+ };
+ int idx = cmd_idx(cmd);
+
+ return (idx >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[idx].fn;
+}
+
+/* ioctl dispatcher */
+static int _autofs_dev_ioctl(unsigned int command, struct autofs_dev_ioctl __user *user)
+{
+ struct autofs_dev_ioctl *param;
+ struct file *fp;
+ struct autofs_sb_info *sbi;
+ unsigned int cmd;
+ ioctl_fn fn = NULL;
+ int err = 0;
+
+ /* only root can play with this */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ cmd = _IOC_NR(command);
+
+ if (_IOC_TYPE(command) != _IOC_TYPE(AUTOFS_DEV_IOCTL_IOC_FIRST) ||
+ cmd - _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST) >= AUTOFS_DEV_IOCTL_IOC_COUNT) {
+ return -ENOTTY;
+ }
+
+ fn = lookup_dev_ioctl(cmd);
+ if (!fn) {
+ WARN("unknown command 0x%08x", command);
+ return -ENOTTY;
+ }
+
+ /*
+ * Trying to avoid low memory issues when a device is
+ * suspended.
+ */
+ current->flags |= PF_MEMALLOC;
+
+ /* Copy the parameters into kernel space. */
+ param = copy_dev_ioctl(user);
+
+ current->flags &= ~PF_MEMALLOC;
+
+ if (IS_ERR(param))
+ return PTR_ERR(param);
+
+ err = validate_dev_ioctl(command, param);
+ if (err)
+ goto out;
+
+ /* The validate routine above always sets the version */
+ if (cmd == AUTOFS_DEV_IOCTL_VERSION_CMD)
+ goto done;
+
+ fp = NULL;
+ sbi = NULL;
+
+ /*
+ * For obvious reasons the openmount can't have a file
+ * descriptor yet. We don't take a reference to the
+ * file during close to allow for immediate release.
+ */
+ if (cmd != AUTOFS_DEV_IOCTL_OPENMOUNT_CMD &&
+ cmd != AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD) {
+ fp = fget(param->ioctlfd);
+ if (!fp) {
+ if (cmd == AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD)
+ goto cont;
+ err = -EBADF;
+ goto out;
+ }
+
+ if (!fp->f_op) {
+ err = -ENOTTY;
+ fput(fp);
+ goto out;
+ }
+
+ sbi = autofs_dev_ioctl_sbi(fp);
+ if (!sbi) {
+ err = -EINVAL;
+ fput(fp);
+ goto out;
+ }
+ }
+cont:
+ err = fn(fp, sbi, param);
+
+ if (fp)
+ fput(fp);
+done:
+ if (!err && copy_to_user(user, param, AUTOFS_DEV_IOCTL_SIZE))
+ err = -EFAULT;
+out:
+ free_dev_ioctl(param);
+ return err;
+}
+
+static long autofs_dev_ioctl(struct file *file, uint command, ulong u)
+{
+ return (long) _autofs_dev_ioctl(command, (struct autofs_dev_ioctl __user *) u);
+}
+
+#ifdef CONFIG_COMPAT
+static long autofs_dev_ioctl_compat(struct file *file, uint command, ulong u)
+{
+ return (long) autofs_dev_ioctl(file, command, (ulong) compat_ptr(u));
+}
+#else
+#define autofs_dev_ioctl_compat NULL
+#endif
+
+static const struct file_operations _dev_ioctl_fops = {
+ .unlocked_ioctl = autofs_dev_ioctl,
+ .compat_ioctl = autofs_dev_ioctl_compat,
+ .owner = THIS_MODULE,
+};
+
+static struct miscdevice _autofs_dev_ioctl_misc = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = AUTOFS_DEVICE_NAME,
+ .fops = &_dev_ioctl_fops
+};
+
+/* Register/deregister misc character device */
+int autofs_dev_ioctl_init(void)
+{
+ int r;
+
+ r = misc_register(&_autofs_dev_ioctl_misc);
+ if (r) {
+ ERROR("misc_register failed for control device");
+ return r;
+ }
+
+ return 0;
+}
+
+void autofs_dev_ioctl_exit(void)
+{
+ if (misc_deregister(&_autofs_dev_ioctl_misc) < 0)
+ ERROR("misc_deregister failed for control device");
+
+ return;
+}
+
diff -up linux-2.6.25-rc2-mm1/include/linux/auto_fs4.h.device-node-ioctl linux-2.6.25-rc2-mm1/include/linux/auto_fs4.h
--- linux-2.6.25-rc2-mm1/include/linux/auto_fs4.h.device-node-ioctl 2008-01-25 07:58:37.000000000 +0900
+++ linux-2.6.25-rc2-mm1/include/linux/auto_fs4.h 2008-02-22 11:51:41.000000000 +0900
@@ -23,7 +23,7 @@
#define AUTOFS_MIN_PROTO_VERSION 3
#define AUTOFS_MAX_PROTO_VERSION 5
-#define AUTOFS_PROTO_SUBVERSION 0
+#define AUTOFS_PROTO_SUBVERSION 1
/* Mask for expire behaviour */
#define AUTOFS_EXP_IMMEDIATE 1
diff -up /dev/null linux-2.6.25-rc2-mm1/include/linux/auto_dev-ioctl.h
--- /dev/null 2008-02-22 18:55:57.149000956 +0900
+++ linux-2.6.25-rc2-mm1/include/linux/auto_dev-ioctl.h 2008-02-22 11:51:41.000000000 +0900
@@ -0,0 +1,114 @@
+/*
+ * linux/include/linux/auto_dev-ioctl.h
+ *
+ * Copyright 2008 Red Hat, Inc. All rights reserved.
+ * Copyright 2008 Ian Kent <raven@xxxxxxxxxx>
+ *
+ * This file is part of the Linux kernel and is made available under
+ * the terms of the GNU General Public License, version 2, or at your
+ * option, any later version, incorporated herein by reference.
+ */
+
+#ifndef _LINUX_AUTO_DEV_IOCTL_H
+#define _LINUX_AUTO_DEV_IOCTL_H
+
+#include <linux/types.h>
+
+#define AUTOFS_DEV_IOCTL_VERSION_MAJOR 1
+#define AUTOFS_DEV_IOCTL_VERSION_MINOR 0
+
+#define AUTOFS_DEVID_LEN 16
+
+/*
+ * An ioctl interface for autofs mount point control.
+ */
+
+/*
+ * All the ioctls use this structure.
+ * When sending a path size must account for the total length
+ * of the chunk of memory otherwise is is the size of the
+ * structure.
+ */
+
+struct autofs_dev_ioctl {
+ __u32 ver_major;
+ __u32 ver_minor;
+ __u32 size; /* total size of data passed in
+ * including this struct */
+ __s32 ioctlfd; /* automount command fd */
+
+ __u32 arg1; /* Command parameters */
+ __u32 arg2;
+
+ char path[0];
+};
+
+static inline void init_autofs_dev_ioctl(struct autofs_dev_ioctl *in)
+{
+ in->ver_major = AUTOFS_DEV_IOCTL_VERSION_MAJOR;
+ in->ver_minor = AUTOFS_DEV_IOCTL_VERSION_MINOR;
+ in->size = sizeof(struct autofs_dev_ioctl);
+ in->ioctlfd = -1;
+ in->arg1 = 0;
+ in->arg2 = 0;
+ return;
+}
+
+/*
+ * If you change this make sure you make the corresponding change
+ * to autofs-dev-ioctl.c:lookup_ioctl()
+ */
+enum {
+ /* Get various version info */
+ AUTOFS_DEV_IOCTL_VERSION_CMD = 0x71,
+ AUTOFS_DEV_IOCTL_PROTOVER_CMD,
+ AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD,
+
+ /* Open mount ioctl fd */
+ AUTOFS_DEV_IOCTL_OPENMOUNT_CMD,
+
+ /* Close mount ioctl fd */
+ AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD,
+
+ /* Mount/expire status returns */
+ AUTOFS_DEV_IOCTL_READY_CMD,
+ AUTOFS_DEV_IOCTL_FAIL_CMD,
+
+ /* Activate/deactivate autofs mount */
+ AUTOFS_DEV_IOCTL_SETPIPEFD_CMD,
+ AUTOFS_DEV_IOCTL_CATATONIC_CMD,
+
+ /* Expiry timeout */
+ AUTOFS_DEV_IOCTL_TIMEOUT_CMD,
+
+ /* Get mount last requesting uid and gid */
+ AUTOFS_DEV_IOCTL_REQUESTOR_CMD,
+
+ /* Check for eligible expire candidates */
+ AUTOFS_DEV_IOCTL_EXPIRE_CMD,
+
+ /* Request busy status */
+ AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD,
+
+ /* Check if path is a mountpoint */
+ AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD,
+};
+
+#define AUTOFS_IOCTL 0x93
+
+#define AUTOFS_DEV_IOCTL_VERSION _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_VERSION_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_PROTOVER _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_PROTOVER_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_PROTOSUBVER _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_OPENMOUNT _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_OPENMOUNT_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_CLOSEMOUNT _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_CLOSEMOUNT_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_READY _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_READY_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_FAIL _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_FAIL_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_SETPIPEFD _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_SETPIPEFD_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_CATATONIC _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_CATATONIC_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_TIMEOUT _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_TIMEOUT_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_REQUESTOR _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_REQUESTOR_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_EXPIRE _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_EXPIRE_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_ASKUMOUNT _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_ASKUMOUNT_CMD, struct autofs_dev_ioctl)
+#define AUTOFS_DEV_IOCTL_ISMOUNTPOINT _IOWR(AUTOFS_IOCTL, AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD, struct autofs_dev_ioctl)
+
+#endif /* _LINUX_AUTO_DEV_IOCTL_H */
--
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