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/*
* linux/fs/nfs/symlink.c
*
* Copyright (C) 1992 Rick Sladkey
*
* Optimization changes Copyright (C) 1994 Florian La Roche
*
* nfs symlink handling code
*/
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/nfs_fs.h>
#include <linux/stat.h>
#include <linux/mm.h>
#include <linux/malloc.h>
#include <linux/string.h>
#include <asm/uaccess.h>
static int nfs_readlink(struct dentry *, char *, int);
static struct dentry *nfs_follow_link(struct dentry *, struct dentry *, unsigned int);
/*
* symlinks can't do much...
*/
struct inode_operations nfs_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 */
nfs_readlink, /* readlink */
nfs_follow_link, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
static int nfs_readlink(struct dentry *dentry, char *buffer, int buflen)
{
int error;
unsigned int len;
char *res;
void *mem;
dfprintk(VFS, "nfs: readlink(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
error = nfs_proc_readlink(NFS_DSERVER(dentry), NFS_FH(dentry),
&mem, &res, &len, NFS_MAXPATHLEN);
if (! error) {
if (len > buflen)
len = buflen;
copy_to_user(buffer, res, len);
error = len;
kfree(mem);
}
return error;
}
static struct dentry *
nfs_follow_link(struct dentry * dentry, struct dentry *base, unsigned int follow)
{
int error;
unsigned int len;
char *res;
void *mem;
char *path;
struct dentry *result;
dfprintk(VFS, "nfs: follow_link(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
error = nfs_proc_readlink(NFS_DSERVER(dentry), NFS_FH(dentry),
&mem, &res, &len, NFS_MAXPATHLEN);
result = ERR_PTR(error);
if (error)
goto out_dput;
result = ERR_PTR(-ENOMEM);
path = kmalloc(len + 1, GFP_KERNEL);
if (!path)
goto out_mem;
memcpy(path, res, len);
path[len] = 0;
kfree(mem);
result = lookup_dentry(path, base, follow);
kfree(path);
out:
return result;
out_mem:
kfree(mem);
out_dput:
dput(base);
goto out;
}
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