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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 */

};