ocfs2: Add ocfs2_read_refcount_block.

Signed-off-by: Tao Ma <tao.ma@oracle.com>

1 files changed, 99 insertions, 0 deletions

diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
new file mode 100644
index 000000000000..a923535d9c37
--- /dev/null
+++ b/fs/ocfs2/refcounttree.c
@@ -0,0 +1,99 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * refcounttree.c
+ *
+ * Copyright (C) 2009 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License version 2 as published by the Free Software Foundation.
+ *
+ * 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.  See the GNU
+ * General Public License for more details.
+ */
+
+#define MLOG_MASK_PREFIX ML_REFCOUNT
+#include <cluster/masklog.h>
+#include "ocfs2.h"
+#include "inode.h"
+#include "alloc.h"
+#include "suballoc.h"
+#include "journal.h"
+#include "uptodate.h"
+#include "super.h"
+#include "buffer_head_io.h"
+#include "blockcheck.h"
+
+static int ocfs2_validate_refcount_block(struct super_block *sb,
+                                         struct buffer_head *bh)
+{
+        int rc;
+        struct ocfs2_refcount_block *rb =
+                (struct ocfs2_refcount_block *)bh->b_data;
+
+        mlog(0, "Validating refcount block %llu\n",
+             (unsigned long long)bh->b_blocknr);
+
+        BUG_ON(!buffer_uptodate(bh));
+
+        /*
+         * If the ecc fails, we return the error but otherwise
+         * leave the filesystem running.  We know any error is
+         * local to this block.
+         */
+        rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &rb->rf_check);
+        if (rc) {
+                mlog(ML_ERROR, "Checksum failed for refcount block %llu\n",
+                     (unsigned long long)bh->b_blocknr);
+                return rc;
+        }
+
+
+        if (!OCFS2_IS_VALID_REFCOUNT_BLOCK(rb)) {
+                ocfs2_error(sb,
+                            "Refcount block #%llu has bad signature %.*s",
+                            (unsigned long long)bh->b_blocknr, 7,
+                            rb->rf_signature);
+                return -EINVAL;
+        }
+
+        if (le64_to_cpu(rb->rf_blkno) != bh->b_blocknr) {
+                ocfs2_error(sb,
+                            "Refcount block #%llu has an invalid rf_blkno "
+                            "of %llu",
+                            (unsigned long long)bh->b_blocknr,
+                            (unsigned long long)le64_to_cpu(rb->rf_blkno));
+                return -EINVAL;
+        }
+
+        if (le32_to_cpu(rb->rf_fs_generation) != OCFS2_SB(sb)->fs_generation) {
+                ocfs2_error(sb,
+                            "Refcount block #%llu has an invalid "
+                            "rf_fs_generation of #%u",
+                            (unsigned long long)bh->b_blocknr,
+                            le32_to_cpu(rb->rf_fs_generation));
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static int ocfs2_read_refcount_block(struct ocfs2_caching_info *ci,
+                                     u64 rb_blkno,
+                                     struct buffer_head **bh)
+{
+        int rc;
+        struct buffer_head *tmp = *bh;
+
+        rc = ocfs2_read_block(ci, rb_blkno, &tmp,
+                              ocfs2_validate_refcount_block);
+
+        /* If ocfs2_read_block() got us a new bh, pass it up. */
+        if (!rc && !*bh)
+                *bh = tmp;
+
+        return rc;
+}