ocfs2: Add extended attribute support

This patch implements storing extended attributes both in inode or a single
external block. We only store EA's in-inode when blocksize > 512 or that
inode block has free space for it. When an EA's value is larger than 80
bytes, we will store the value via b-tree outside inode or block.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index ce75ca3..cae0dd4 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -188,6 +188,7 @@
 	OCFS2_MOUNT_ERRORS_PANIC = 1 << 3, /* Panic on errors */
 	OCFS2_MOUNT_DATA_WRITEBACK = 1 << 4, /* No data ordering */
 	OCFS2_MOUNT_LOCALFLOCKS = 1 << 5, /* No cluster aware user file locks */
+	OCFS2_MOUNT_NOUSERXATTR = 1 << 6, /* No user xattr */
 };
 
 #define OCFS2_OSB_SOFT_RO	0x0001
@@ -218,6 +219,7 @@
 	u32 bitmap_cpg;
 	u8 *uuid;
 	char *uuid_str;
+	u32 uuid_hash;
 	u8 *vol_label;
 	u64 first_cluster_group_blkno;
 	u32 fs_generation;