swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: 07a2039b8eb0af4ff464efd3dfd95de5c02648c6 authored by Linus Torvalds on 10 June 2009, 03:05:27 UTC
Linux 2.6.30
Linux 2.6.30
Tip revision: 07a2039
inode.c
/* -*- linux-c -*- --------------------------------------------------------- *
*
* linux/fs/autofs/inode.c
*
* Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
*
* 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/mm.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/parser.h>
#include <linux/bitops.h>
#include <linux/magic.h>
#include "autofs_i.h"
#include <linux/module.h>
void autofs_kill_sb(struct super_block *sb)
{
struct autofs_sb_info *sbi = autofs_sbi(sb);
unsigned int n;
/*
* 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;
if (!sbi->catatonic)
autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
put_pid(sbi->oz_pgrp);
autofs_hash_nuke(sbi);
for (n = 0; n < AUTOFS_MAX_SYMLINKS; n++) {
if (test_bit(n, sbi->symlink_bitmap))
kfree(sbi->symlink[n].data);
}
kfree(sb->s_fs_info);
out_kill_sb:
DPRINTK(("autofs: shutting down\n"));
kill_anon_super(sb);
}
static const struct super_operations autofs_sops = {
.statfs = simple_statfs,
.show_options = generic_show_options,
};
enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
static const match_table_t autofs_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_err, NULL}
};
static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
pid_t *pgrp, 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 = *maxproto = AUTOFS_PROTO_VERSION;
*pipefd = -1;
if (!options)
return 1;
while ((p = strsep(&options, ",")) != NULL) {
int token;
if (!*p)
continue;
token = match_token(p, autofs_tokens, args);
switch (token) {
case Opt_fd:
if (match_int(&args[0], &option))
return 1;
*pipefd = option;
break;
case Opt_uid:
if (match_int(&args[0], &option))
return 1;
*uid = option;
break;
case Opt_gid:
if (match_int(&args[0], &option))
return 1;
*gid = option;
break;
case Opt_pgrp:
if (match_int(&args[0], &option))
return 1;
*pgrp = option;
break;
case Opt_minproto:
if (match_int(&args[0], &option))
return 1;
*minproto = option;
break;
case Opt_maxproto:
if (match_int(&args[0], &option))
return 1;
*maxproto = option;
break;
default:
return 1;
}
}
return (*pipefd < 0);
}
int autofs_fill_super(struct super_block *s, void *data, int silent)
{
struct inode * root_inode;
struct dentry * root;
struct file * pipe;
int pipefd;
struct autofs_sb_info *sbi;
int minproto, maxproto;
pid_t pgid;
save_mount_options(s, data);
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
goto fail_unlock;
DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
s->s_fs_info = sbi;
sbi->magic = AUTOFS_SBI_MAGIC;
sbi->pipe = NULL;
sbi->catatonic = 1;
sbi->exp_timeout = 0;
autofs_initialize_hash(&sbi->dirhash);
sbi->queues = NULL;
memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = AUTOFS_SUPER_MAGIC;
s->s_op = &autofs_sops;
s->s_time_gran = 1;
sbi->sb = s;
root_inode = autofs_iget(s, AUTOFS_ROOT_INO);
if (IS_ERR(root_inode))
goto fail_free;
root = d_alloc_root(root_inode);
pipe = NULL;
if (!root)
goto fail_iput;
/* Can this call block? - WTF cares? s is locked. */
if (parse_options(data, &pipefd, &root_inode->i_uid,
&root_inode->i_gid, &pgid, &minproto,
&maxproto)) {
printk("autofs: called with bogus options\n");
goto fail_dput;
}
/* Couldn't this be tested earlier? */
if (minproto > AUTOFS_PROTO_VERSION ||
maxproto < AUTOFS_PROTO_VERSION) {
printk("autofs: kernel does not match daemon version\n");
goto fail_dput;
}
DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid));
sbi->oz_pgrp = find_get_pid(pgid);
if (!sbi->oz_pgrp) {
printk("autofs: could not find process group %d\n", pgid);
goto fail_dput;
}
pipe = fget(pipefd);
if (!pipe) {
printk("autofs: could not open pipe file descriptor\n");
goto fail_put_pid;
}
if (!pipe->f_op || !pipe->f_op->write)
goto fail_fput;
sbi->pipe = pipe;
sbi->catatonic = 0;
/*
* Success! Install the root dentry now to indicate completion.
*/
s->s_root = root;
return 0;
fail_fput:
printk("autofs: pipe file descriptor does not contain proper ops\n");
fput(pipe);
fail_put_pid:
put_pid(sbi->oz_pgrp);
fail_dput:
dput(root);
goto fail_free;
fail_iput:
printk("autofs: get root dentry failed\n");
iput(root_inode);
fail_free:
kfree(sbi);
s->s_fs_info = NULL;
fail_unlock:
return -EINVAL;
}
struct inode *autofs_iget(struct super_block *sb, unsigned long ino)
{
unsigned int n;
struct autofs_sb_info *sbi = autofs_sbi(sb);
struct inode *inode;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
/* Initialize to the default case (stub directory) */
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
inode->i_nlink = 2;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
if (ino == AUTOFS_ROOT_INO) {
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
inode->i_op = &autofs_root_inode_operations;
inode->i_fop = &autofs_root_operations;
goto done;
}
inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
if (ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO) {
/* Symlink inode - should be in symlink list */
struct autofs_symlink *sl;
n = ino - AUTOFS_FIRST_SYMLINK;
if (n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) {
printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
goto done;
}
inode->i_op = &autofs_symlink_inode_operations;
sl = &sbi->symlink[n];
inode->i_private = sl;
inode->i_mode = S_IFLNK | S_IRWXUGO;
inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
inode->i_size = sl->len;
inode->i_nlink = 1;
}
done:
unlock_new_inode(inode);
return inode;
}