[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 000000000000..f6986bd79e75
--- /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,
+};