5 files changed, 105 insertions, 0 deletions

diff --git a/fs/ocfs2/Makefile b/fs/ocfs2/Makefile
index 01596079dd63..31f25ce32c97 100644
--- a/fs/ocfs2/Makefile
+++ b/fs/ocfs2/Makefile
@@ -28,6 +28,7 @@ ocfs2-objs := \
         locks.o                 \
         mmap.o                  \
         namei.o                 \
+        refcounttree.o          \
         resize.o                \
         slot_map.o              \
         suballoc.o              \
diff --git a/fs/ocfs2/cluster/masklog.c b/fs/ocfs2/cluster/masklog.c
index 96df5416993e..1cd2934de615 100644
--- a/fs/ocfs2/cluster/masklog.c
+++ b/fs/ocfs2/cluster/masklog.c
@@ -111,6 +111,7 @@ static struct mlog_attribute mlog_attrs[MLOG_MAX_BITS] = {
         define_mask(EXPORT),
         define_mask(XATTR),
         define_mask(QUOTA),
+        define_mask(REFCOUNT),
         define_mask(ERROR),
         define_mask(NOTICE),
         define_mask(KTHREAD),
diff --git a/fs/ocfs2/cluster/masklog.h b/fs/ocfs2/cluster/masklog.h
index 696c32e50716..9b4d11726cf2 100644
--- a/fs/ocfs2/cluster/masklog.h
+++ b/fs/ocfs2/cluster/masklog.h
@@ -113,6 +113,7 @@
 #define ML_EXPORT       0x0000000010000000ULL /* ocfs2 export operations */
 #define ML_XATTR        0x0000000020000000ULL /* ocfs2 extended attributes */
 #define ML_QUOTA        0x0000000040000000ULL /* ocfs2 quota operations */
+#define ML_REFCOUNT     0x0000000080000000ULL /* refcount tree operations */
 /* bits that are infrequently given and frequently matched in the high word */
 #define ML_ERROR        0x0000000100000000ULL /* sent to KERN_ERR */
 #define ML_NOTICE       0x0000000200000000ULL /* setn to KERN_NOTICE */
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index d370262b3621..6688d19e4451 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -610,6 +610,9 @@ static inline int ocfs2_uses_extended_slot_map(struct ocfs2_super *osb)
 #define OCFS2_IS_VALID_DX_LEAF(ptr)                                     \
         (!strcmp((ptr)->dl_signature, OCFS2_DX_LEAF_SIGNATURE))
 
+#define OCFS2_IS_VALID_REFCOUNT_BLOCK(ptr)                              \
+        (!strcmp((ptr)->rf_signature, OCFS2_REFCOUNT_BLOCK_SIGNATURE))
+
 static inline unsigned long ino_from_blkno(struct super_block *sb,
                                            u64 blkno)
 {
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;
+}