https://github.com/torvalds/linux
Tip revision: 60d4684068ff1eec78f55b5888d0bd2d4cca1520 authored by Linus Torvalds on 28 August 2006, 03:41:48 UTC
Linux v2.6.18-rc5
Linux v2.6.18-rc5
Tip revision: 60d4684
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 "autofs_i.h"
#include <linux/module.h>
static void autofs_put_super(struct super_block *sb)
{
struct autofs_sb_info *sbi = autofs_sbi(sb);
unsigned int n;
if ( !sbi->catatonic )
autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
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);
DPRINTK(("autofs: shutting down\n"));
}
static void autofs_read_inode(struct inode *inode);
static struct super_operations autofs_sops = {
.read_inode = autofs_read_inode,
.put_super = autofs_put_super,
.statfs = simple_statfs,
};
enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
static 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 = process_group(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;
sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
if ( !sbi )
goto fail_unlock;
memset(sbi, 0, sizeof(*sbi));
DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
s->s_fs_info = sbi;
sbi->magic = AUTOFS_SBI_MAGIC;
sbi->catatonic = 0;
sbi->exp_timeout = 0;
sbi->oz_pgrp = process_group(current);
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 = iget(s, AUTOFS_ROOT_INO);
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,&sbi->oz_pgrp,&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, sbi->oz_pgrp));
pipe = fget(pipefd);
if ( !pipe ) {
printk("autofs: could not open pipe file descriptor\n");
goto fail_dput;
}
if ( !pipe->f_op || !pipe->f_op->write )
goto fail_fput;
sbi->pipe = pipe;
/*
* 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_dput:
dput(root);
goto fail_free;
fail_iput:
printk("autofs: get root dentry failed\n");
iput(root_inode);
fail_free:
kfree(sbi);
fail_unlock:
return -EINVAL;
}
static void autofs_read_inode(struct inode *inode)
{
ino_t ino = inode->i_ino;
unsigned int n;
struct autofs_sb_info *sbi = autofs_sbi(inode->i_sb);
/* 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;
inode->i_blocks = 0;
inode->i_blksize = 1024;
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;
inode->i_uid = inode->i_gid = 0; /* Changed in read_super */
return;
}
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);
return;
}
inode->i_op = &autofs_symlink_inode_operations;
sl = &sbi->symlink[n];
inode->u.generic_ip = 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;
}
}