xfs: create incore realtime group structures

Create an incore object that will contain information about a realtime
allocation group.  This will eventually enable us to shard the realtime
section in a similar manner to how we shard the data section.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 5c514a22d501..035f3fea3ce1 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -184,6 +184,14 @@ typedef struct xfs_sb {
 	 */
 	xfs_ino_t	sb_metadirino;
 
+	/*
+	 * Realtime group geometry information.  On disk these fields live in
+	 * the rsumino slot, but we cache them separately in the in-core super
+	 * for easy access.
+	 */
+	xfs_rgblock_t	sb_rgblocks;	/* size of a realtime group */
+	xfs_rgnumber_t	sb_rgcount;	/* number of realtime groups */
+
 	/* must be padded to 64 bit alignment */
 } xfs_sb_t;