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>

1 files changed, 52 insertions, 0 deletions

diff --git a/fs/xfs/xfs_icreate_item.h b/fs/xfs/xfs_icreate_item.h
new file mode 100644
index 00000000000..88ba8aa0bc4
--- /dev/null
+++ b/fs/xfs/xfs_icreate_item.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2008-2010, Dave Chinner
+ * 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 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would 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 the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#ifndef XFS_ICREATE_ITEM_H
+#define XFS_ICREATE_ITEM_H	1
+
+/*
+ * on disk log item structure
+ *
+ * Log recovery assumes the first two entries are the type and size and they fit
+ * in 32 bits. Also in host order (ugh) so they have to be 32 bit aligned so
+ * decoding can be done correctly.
+ */
+struct xfs_icreate_log {
+	__uint16_t	icl_type;	/* type of log format structure */
+	__uint16_t	icl_size;	/* size of log format structure */
+	__be32		icl_ag;		/* ag being allocated in */
+	__be32		icl_agbno;	/* start block of inode range */
+	__be32		icl_count;	/* number of inodes to initialise */
+	__be32		icl_isize;	/* size of inodes */
+	__be32		icl_length;	/* length of extent to initialise */
+	__be32		icl_gen;	/* inode generation number to use */
+};
+
+/* in memory log item structure */
+struct xfs_icreate_item {
+	struct xfs_log_item	ic_item;
+	struct xfs_icreate_log	ic_format;
+};
+
+extern kmem_zone_t *xfs_icreate_zone;	/* inode create item zone */
+
+void xfs_icreate_log(struct xfs_trans *tp, xfs_agnumber_t agno,
+			xfs_agblock_t agbno, unsigned int count,
+			unsigned int inode_size, xfs_agblock_t length,
+			unsigned int generation);
+
+#endif	/* XFS_ICREATE_ITEM_H */