[PATCH] OCFS2: The Second Oracle Cluster Filesystem

The OCFS2 file system module.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>

1 files changed, 180 insertions, 0 deletions

diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c
new file mode 100644
index 0000000..f6986bd
--- /dev/null
+++ b/fs/ocfs2/symlink.c
@@ -0,0 +1,180 @@
+/* -*- 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_cache_page(mapping, 0,
+			       (filler_t *)mapping->a_ops->readpage, 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)
+		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,
+};