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-rw-r--r--kernel/fs/btrfs/hash.h42
1 files changed, 42 insertions, 0 deletions
diff --git a/kernel/fs/btrfs/hash.h b/kernel/fs/btrfs/hash.h
new file mode 100644
index 000000000..118a2316e
--- /dev/null
+++ b/kernel/fs/btrfs/hash.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2007 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 v2 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.
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef __HASH__
+#define __HASH__
+
+int __init btrfs_hash_init(void);
+
+void btrfs_hash_exit(void);
+
+u32 btrfs_crc32c(u32 crc, const void *address, unsigned int length);
+
+static inline u64 btrfs_name_hash(const char *name, int len)
+{
+ return btrfs_crc32c((u32)~1, name, len);
+}
+
+/*
+ * Figure the key offset of an extended inode ref
+ */
+static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
+ int len)
+{
+ return (u64) btrfs_crc32c(parent_objectid, name, len);
+}
+
+#endif