180 lines
4.1 KiB
C
180 lines
4.1 KiB
C
/* -*- 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;
|
|
}
|
|
|
|
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);
|
|
if (status && status != -ENOENT)
|
|
mlog_errno(status);
|
|
bail:
|
|
if (page) {
|
|
kunmap(page);
|
|
page_cache_release(page);
|
|
}
|
|
if (bh)
|
|
brelse(bh);
|
|
|
|
return ERR_PTR(status);
|
|
}
|
|
|
|
struct inode_operations ocfs2_symlink_inode_operations = {
|
|
.readlink = page_readlink,
|
|
.follow_link = ocfs2_follow_link,
|
|
.getattr = ocfs2_getattr,
|
|
};
|
|
struct inode_operations ocfs2_fast_symlink_inode_operations = {
|
|
.readlink = ocfs2_readlink,
|
|
.follow_link = ocfs2_follow_link,
|
|
.getattr = ocfs2_getattr,
|
|
};
|