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|
/* -*- c -*- --------------------------------------------------------------- *
*
* linux/fs/autofs/inode.c
*
* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
* Copyright 2005-2006 Ian Kent <raven@themaw.net>
*
* 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/kernel.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/seq_file.h>
#include <linux/pagemap.h>
#include <linux/parser.h>
#include <linux/bitops.h>
#include <linux/magic.h>
#include "autofs_i.h"
#include <linux/module.h>
static void ino_lnkfree(struct autofs_info *ino)
{
if (ino->u.symlink) {
kfree(ino->u.symlink);
ino->u.symlink = NULL;
}
}
struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
struct autofs_sb_info *sbi, mode_t mode)
{
int reinit = 1;
if (ino == NULL) {
reinit = 0;
ino = kmalloc(sizeof(*ino), GFP_KERNEL);
}
if (ino == NULL)
return NULL;
if (!reinit) {
ino->flags = 0;
ino->inode = NULL;
ino->dentry = NULL;
ino->size = 0;
INIT_LIST_HEAD(&ino->active);
INIT_LIST_HEAD(&ino->expiring);
atomic_set(&ino->count, 0);
}
ino->uid = 0;
ino->gid = 0;
ino->mode = mode;
ino->last_used = jiffies;
ino->sbi = sbi;
if (reinit && ino->free)
(ino->free)(ino);
memset(&ino->u, 0, sizeof(ino->u));
ino->free = NULL;
if (S_ISLNK(mode))
ino->free = ino_lnkfree;
return ino;
}
void autofs4_free_ino(struct autofs_info *ino)
{
struct autofs_info *p_ino;
if (ino->dentry) {
ino->dentry->d_fsdata = NULL;
if (ino->dentry->d_inode) {
struct dentry *parent = ino->dentry->d_parent;
if (atomic_dec_and_test(&ino->count)) {
p_ino = autofs4_dentry_ino(parent);
if (p_ino && parent != ino->dentry)
atomic_dec(&p_ino->count);
}
dput(ino->dentry);
}
ino->dentry = NULL;
}
if (ino->free)
(ino->free)(ino);
kfree(ino);
}
/*
* Deal with the infamous "Busy inodes after umount ..." message.
*
* Clean up the dentry tree. This happens with autofs if the user
* space program goes away due to a SIGKILL, SIGSEGV etc.
*/
static void autofs4_force_release(struct autofs_sb_info *sbi)
{
struct dentry *this_parent = sbi->sb->s_root;
struct list_head *next;
if (!sbi->sb->s_root)
return;
spin_lock(&dcache_lock);
repeat:
next = this_parent->d_subdirs.next;
resume:
while (next != &this_parent->d_subdirs) {
struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
/* Negative dentry - don`t care */
if (!simple_positive(dentry)) {
next = next->next;
continue;
}
if (!list_empty(&dentry->d_subdirs)) {
this_parent = dentry;
goto repeat;
}
next = next->next;
spin_unlock(&dcache_lock);
DPRINTK("dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
dput(dentry);
spin_lock(&dcache_lock);
}
if (this_parent != sbi->sb->s_root) {
struct dentry *dentry = this_parent;
next = this_parent->d_u.d_child.next;
this_parent = this_parent->d_parent;
spin_unlock(&dcache_lock);
DPRINTK("parent dentry %p %.*s",
dentry, (int)dentry->d_name.len, dentry->d_name.name);
dput(dentry);
spin_lock(&dcache_lock);
goto resume;
}
spin_unlock(&dcache_lock);
}
void autofs4_kill_sb(struct super_block *sb)
{
struct autofs_sb_info *sbi = autofs4_sbi(sb);
/*
* In the event of a failure in get_sb_nodev the superblock
* info is not present so nothing else has been setup, so
* just call kill_anon_super when we are called from
* deactivate_super.
*/
if (!sbi)
goto out_kill_sb;
/* Free wait queues, close pipe */
autofs4_catatonic_mode(sbi);
/* Clean up and release dangling references */
autofs4_force_release(sbi);
sb->s_fs_info = NULL;
kfree(sbi);
out_kill_sb:
DPRINTK("shutting down");
kill_anon_super(sb);
}
static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
{
struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
struct inode *root_inode = mnt->mnt_sb->s_root->d_inode;
if (!sbi)
return 0;
seq_printf(m, ",fd=%d", sbi->pipefd);
if (root_inode->i_uid != 0)
seq_printf(m, ",uid=%u", root_inode->i_uid);
if (root_inode->i_gid != 0)
seq_printf(m, ",gid=%u", root_inode->i_gid);
seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
seq_printf(m, ",minproto=%d", sbi->min_proto);
seq_printf(m, ",maxproto=%d", sbi->max_proto);
if (autofs_type_offset(sbi->type))
seq_printf(m, ",offset");
else if (autofs_type_direct(sbi->type))
seq_printf(m, ",direct");
else
seq_printf(m, ",indirect");
return 0;
}
static const struct super_operations autofs4_sops = {
.statfs = simple_statfs,
.show_options = autofs4_show_options,
};
enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
Opt_indirect, Opt_direct, Opt_offset};
static const match_table_t tokens = {
{Opt_fd, "fd=%u"},
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_pgrp, "pgrp=%u"},
{Opt_minproto, "minproto=%u"},
{Opt_maxproto, "maxproto=%u"},
{Opt_indirect, "indirect"},
{Opt_direct, "direct"},
{Opt_offset, "offset"},
{Opt_err, NULL}
};
static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int option;
*uid = current_uid();
*gid = current_gid();
*pgrp = task_pgrp_nr(current);
*minproto = AUTOFS_MIN_PROTO_VERSION;
*maxproto = AUTOFS_MAX_PROTO_VERSION;
*pipefd = -1;
if (!options)
return 1;
while ((p = strsep(&options, ",")) != NULL) {
int token;
|