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/*
* linux/ufs/ufs/symlink.c
*
* Copyright (C) 1998
* Daniel Pirkl <daniel.pirkl@emai.cz>
* Charles University, Faculty of Mathematics and Physics
*
* from
*
* linux/fs/ext2/symlink.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/symlink.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* ext2 symlink handling code
*/
#include <asm/uaccess.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/stat.h>
#undef UFS_SYMLINK_DEBUG
#ifdef UFS_SYMLINK_DEBUG
#define UFSD(x) printk("(%s, %d), %s:", __FILE__, __LINE__, __FUNCTION__); printk x;
#else
#define UFSD(x)
#endif
static struct dentry * ufs_follow_link(struct dentry * dentry,
struct dentry * base, unsigned int follow)
{
struct inode * inode;
struct buffer_head * bh;
int error;
char * link;
UFSD(("ENTER\n"))
inode = dentry->d_inode;
bh = NULL;
/* slow symlink */
if (inode->i_blocks) {
if (!(bh = ufs_bread (inode, 0, 0, &error))) {
dput(base);
return ERR_PTR(-EIO);
}
link = bh->b_data;
}
/* fast symlink */
else {
link = (char *) inode->u.ufs_i.i_u1.i_symlink;
}
UPDATE_ATIME(inode);
base = lookup_dentry(link, base, follow);
if (bh)
brelse(bh);
UFSD(("EXIT\n"))
return base;
}
static int ufs_readlink (struct dentry * dentry, char * buffer, int buflen)
{
struct super_block * sb;
struct inode * inode;
struct buffer_head * bh;
char * link;
int i;
UFSD(("ENTER\n"))
inode = dentry->d_inode;
sb = inode->i_sb;
bh = NULL;
if (buflen > sb->s_blocksize - 1)
buflen = sb->s_blocksize - 1;
/* slow symlink */
if (inode->i_blocks) {
int err;
bh = ufs_bread (inode, 0, 0, &err);
if (!bh) {
if(err < 0) /* indicate type of error */
return err;
return 0;
}
link = bh->b_data;
}
/* fast symlink */
else {
link = (char *) inode->u.ufs_i.i_u1.i_symlink;
}
i = 0;
while (i < buflen && link[i])
i++;
if (copy_to_user(buffer, link, i))
i = -EFAULT;
UPDATE_ATIME(inode);
if (bh)
brelse (bh);
UFSD(("ENTER\n"))
return i;
}
struct inode_operations ufs_symlink_inode_operations = {
NULL, /* no file-operations */
NULL, /* create */
NULL, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
ufs_readlink, /* readlink */
ufs_follow_link, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL, /* permission */
NULL /* smap */
};
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