[XFS] kill struct xfs_btree_hdr

This type is only embedded in struct xfs_btree_block and never used
directly. By moving the fields directly into struct xfs_btree_block a lot
of the macros for struct xfs_btree_sblock and struct xfs_btree_lblock can
be used for struct xfs_btree_block too now which helps greatly with some
of the migrations during implementing the generic btree code.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32174a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

fs/xfs/xfs_btree.c

@@ -62,13 +62,13 @@ xfs_btree_maxrecs(
 	case XFS_BTNUM_BNO:
 	case XFS_BTNUM_CNT:
 		return (int)XFS_ALLOC_BLOCK_MAXRECS(
-				be16_to_cpu(block->bb_h.bb_level), cur);
+				be16_to_cpu(block->bb_level), cur);
 	case XFS_BTNUM_BMAP:
 		return (int)XFS_BMAP_BLOCK_IMAXRECS(
-				be16_to_cpu(block->bb_h.bb_level), cur);
+				be16_to_cpu(block->bb_level), cur);
 	case XFS_BTNUM_INO:
 		return (int)XFS_INOBT_BLOCK_MAXRECS(
-				be16_to_cpu(block->bb_h.bb_level), cur);
+				be16_to_cpu(block->bb_level), cur);
 	default:
 		ASSERT(0);
 		return 0;
@@ -634,7 +634,7 @@ xfs_btree_firstrec(
 	/*
 	 * It's empty, there is no such record.
 	 */
-	if (!block->bb_h.bb_numrecs)
+	if (!block->bb_numrecs)
 		return 0;
 	/*
 	 * Set the ptr value to 1, that's the first record/key.
@@ -663,12 +663,12 @@ xfs_btree_lastrec(
 	/*
 	 * It's empty, there is no such record.
 	 */
-	if (!block->bb_h.bb_numrecs)
+	if (!block->bb_numrecs)
 		return 0;
 	/*
 	 * Set the ptr value to numrecs, that's the last record/key.
 	 */
-	cur->bc_ptrs[level] = be16_to_cpu(block->bb_h.bb_numrecs);
+	cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
 	return 1;
 }
 

fs/xfs/xfs_btree.h

@@ -63,15 +63,10 @@ typedef struct xfs_btree_lblock {
 /*
  * Combined header and structure, used by common code.
  */
-typedef struct xfs_btree_hdr
-{
+typedef struct xfs_btree_block {
 	__be32		bb_magic;	/* magic number for block type */
 	__be16		bb_level;	/* 0 is a leaf */
 	__be16		bb_numrecs;	/* current # of data records */
-} xfs_btree_hdr_t;
-
-typedef struct xfs_btree_block {
-	xfs_btree_hdr_t	bb_h;		/* header */
 	union {
 		struct {
 			__be32		bb_leftsib;