xfs: Inode create log items

Introduce the inode create log item type for logical inode create logging.
Instead of logging the changes in buffers, pass the range to be
initialised through the log by a new transaction type.  This reduces
the amount of log space required to record initialisation during
allocation from about 128 bytes per inode to a small fixed amount
per inode extent to be initialised.

This requires a new log item type to track it through the log
and the AIL. This is a relatively simple item - most callbacks are
noops as this item has the same life cycle as the transaction.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

fs/xfs/xfs_trans.h

@@ -48,6 +48,7 @@ typedef struct xfs_trans_header {
 #define	XFS_LI_BUF		0x123c	/* v2 bufs, variable sized inode bufs */
 #define	XFS_LI_DQUOT		0x123d
 #define	XFS_LI_QUOTAOFF		0x123e
+#define	XFS_LI_ICREATE		0x123f
 
 #define XFS_LI_TYPE_DESC \
 	{ XFS_LI_EFI,		"XFS_LI_EFI" }, \
@@ -107,7 +108,8 @@ typedef struct xfs_trans_header {
 #define	XFS_TRANS_SWAPEXT		40
 #define	XFS_TRANS_SB_COUNT		41
 #define	XFS_TRANS_CHECKPOINT		42
-#define	XFS_TRANS_TYPE_MAX		42
+#define	XFS_TRANS_ICREATE		43
+#define	XFS_TRANS_TYPE_MAX		43
 /* new transaction types need to be reflected in xfs_logprint(8) */
 
 #define XFS_TRANS_TYPES \