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/* -*- linux-c -*- --------------------------------------------------------- *
*
* linux/fs/autofs/symlink.c
*
* Copyright 1997 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/string.h>
#include <linux/sched.h>
#include "autofs_i.h"
static int autofs_follow_link(struct inode *dir, struct inode *inode,
int flag, int mode, struct inode **res_inode)
{
int error;
char *link;
*res_inode = NULL;
if (!dir) {
dir = current->fs->root;
dir->i_count++;
}
if (!inode) {
iput(dir);
return -ENOENT;
}
if (!S_ISLNK(inode->i_mode)) {
iput(dir);
*res_inode = inode;
return 0;
}
if (current->link_count > 5) {
iput(dir);
iput(inode);
return -ELOOP;
}
link = ((struct autofs_symlink *)inode->u.generic_ip)->data;
current->link_count++;
error = open_namei(link,flag,mode,res_inode,dir);
current->link_count--;
iput(inode);
return error;
}
static int autofs_readlink(struct inode *inode, char *buffer, int buflen)
{
struct autofs_symlink *sl;
int len;
if (!S_ISLNK(inode->i_mode)) {
iput(inode);
return -EINVAL;
}
sl = (struct autofs_symlink *)inode->u.generic_ip;
len = sl->len;
if (len > buflen) len = buflen;
copy_to_user(buffer,sl->data,len);
iput(inode);
return len;
}
struct inode_operations autofs_symlink_inode_operations = {
NULL, /* file operations */
NULL, /* create */
NULL, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
autofs_readlink, /* readlink */
autofs_follow_link, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
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