/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* linux/cluster/ssi/cfs/symlink.c
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE
* or NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Questions/Comments/Bugfixes to ssic-linux-devel@lists.sourceforge.net
*
* Copyright (C) 1992 Rick Sladkey
*
* Optimization changes Copyright (C) 1994 Florian La Roche
*
* Jun 7 1999, cache symlink lookups in the page cache. -DaveM
*
* Portions Copyright (C) 2001 Compaq Computer Corporation
*
* ocfs2 symlink handling code.
*
* Copyright (C) 2004, 2005 Oracle.
*
*/
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/utsname.h>
#define MLOG_MASK_PREFIX ML_NAMEI
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "alloc.h"
#include "file.h"
#include "inode.h"
#include "journal.h"
#include "symlink.h"
#include "buffer_head_io.h"
static char *ocfs2_page_getlink(struct dentry * dentry,
struct page **ppage);
static char *ocfs2_fast_symlink_getlink(struct inode *inode,
struct buffer_head **bh);
/* get the link contents into pagecache */
static char *ocfs2_page_getlink(struct dentry * dentry,
struct page **ppage)
{
struct page * page;
struct address_space *mapping = dentry->d_inode->i_mapping;
page = read_mapping_page(mapping, 0, NULL);
if (IS_ERR(page))
goto sync_fail;
wait_on_page_locked(page);
if (!PageUptodate(page))
goto async_fail;
*ppage = page;
return kmap(page);
async_fail:
page_cache_release(page);
return ERR_PTR(-EIO);
sync_fail:
return (char*)page;
}
static char *ocfs2_fast_symlink_getlink(struct inode *inode,
struct buffer_head **bh)
{
int status;
char *link = NULL;
struct ocfs2_dinode *fe;
mlog_entry_void();
status = ocfs2_read_block(OCFS2_SB(inode->i_sb),
OCFS2_I(inode)->ip_blkno,
bh,
OCFS2_BH_CACHED,
inode);
if (status < 0) {
mlog_errno(status);
link = ERR_PTR(status);
goto bail;
}
fe = (struct ocfs2_dinode *) (*bh)->b_data;
link = (char *) fe->id2.i_symlink;
bail:
mlog_exit(status);
return link;
}
static int ocfs2_readlink(struct dentry *dentry,
char __user *buffer,
int buflen)
{
int ret;
char *link;
struct buffer_head *bh = NULL;
struct inode *inode = dentry->d_inode;
mlog_entry_void();
link = ocfs2_fast_symlink_getlink(inode, &bh);
if (IS_ERR(link)) {
ret = PTR_ERR(link);
goto out;
}
/*
* Without vfsmount we can't update atime now,
* but we will update atime here ultimately.
*/
ret = vfs_readlink(dentry, buffer, buflen, link);
brelse(bh);
out:
mlog_exit(ret);
return ret;
}
static void *ocfs2_follow_link(struct dentry *dentry,
struct nameidata *nd)
{
int status;
char *link;
struct inode *inode = dentry->d_inode;
struct page *page = NULL;
struct buffer_head *bh = NULL;
if (ocfs2_inode_is_fast_symlink(inode))
link = ocfs2_fast_symlink_getlink(inode, &bh);
else
link = ocfs2_page_getlink(dentry, &page);
if (IS_ERR(link)) {
status = PTR_ERR(link);
mlog_errno(status);
goto bail;
}
status = vfs_follow_link(nd, link);
bail:
if (page) {
kunmap(page);
page_cache_release(page);
}
if (bh)
brelse(bh);
return ERR_PTR(status);
}
const struct inode_operations ocfs2_symlink_inode_operations = {
.readlink = page_readlink,
.follow_link = ocfs2_follow_link,
.getattr = ocfs2_getattr,
};
const struct inode_operations ocfs2_fast_symlink_inode_operations = {
.readlink = ocfs2_readlink,
.follow_link = ocfs2_follow_link,
.getattr = ocfs2_getattr,
};
