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, 195 insertions, 0 deletions

diff --git a/fs/xfs/xfs_icreate_item.c b/fs/xfs/xfs_icreate_item.c
new file mode 100644
index 000000000000..7716a4e7375e
--- /dev/null
+++ b/fs/xfs/xfs_icreate_item.c
@@ -0,0 +1,195 @@
+/*
+ * Copyright (c) 2008-2010, 2013 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
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_types.h"
+#include "xfs_bit.h"
+#include "xfs_log.h"
+#include "xfs_inum.h"
+#include "xfs_trans.h"
+#include "xfs_buf_item.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_dir2.h"
+#include "xfs_mount.h"
+#include "xfs_trans_priv.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_attr_sf.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_inode_item.h"
+#include "xfs_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_error.h"
+#include "xfs_icreate_item.h"
+
+kmem_zone_t	*xfs_icreate_zone;		/* inode create item zone */
+
+static inline struct xfs_icreate_item *ICR_ITEM(struct xfs_log_item *lip)
+{
+	return container_of(lip, struct xfs_icreate_item, ic_item);
+}
+
+/*
+ * This returns the number of iovecs needed to log the given inode item.
+ *
+ * We only need one iovec for the icreate log structure.
+ */
+STATIC uint
+xfs_icreate_item_size(
+	struct xfs_log_item	*lip)
+{
+	return 1;
+}
+
+/*
+ * This is called to fill in the vector of log iovecs for the
+ * given inode create log item.
+ */
+STATIC void
+xfs_icreate_item_format(
+	struct xfs_log_item	*lip,
+	struct xfs_log_iovec	*log_vector)
+{
+	struct xfs_icreate_item	*icp = ICR_ITEM(lip);
+
+	log_vector->i_addr = (xfs_caddr_t)&icp->ic_format;
+	log_vector->i_len  = sizeof(struct xfs_icreate_log);
+	log_vector->i_type = XLOG_REG_TYPE_ICREATE;
+}
+
+
+/* Pinning has no meaning for the create item, so just return. */
+STATIC void
+xfs_icreate_item_pin(
+	struct xfs_log_item	*lip)
+{
+}
+
+
+/* pinning has no meaning for the create item, so just return. */
+STATIC void
+xfs_icreate_item_unpin(
+	struct xfs_log_item	*lip,
+	int			remove)
+{
+}
+
+STATIC void
+xfs_icreate_item_unlock(
+	struct xfs_log_item	*lip)
+{
+	struct xfs_icreate_item	*icp = ICR_ITEM(lip);
+
+	if (icp->ic_item.li_flags & XFS_LI_ABORTED)
+		kmem_zone_free(xfs_icreate_zone, icp);
+	return;
+}
+
+/*
+ * Because we have ordered buffers being tracked in the AIL for the inode
+ * creation, we don't need the create item after this. Hence we can free
+ * the log item and return -1 to tell the caller we're done with the item.
+ */
+STATIC xfs_lsn_t
+xfs_icreate_item_committed(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+	struct xfs_icreate_item	*icp = ICR_ITEM(lip);
+
+	kmem_zone_free(xfs_icreate_zone, icp);
+	return (xfs_lsn_t)-1;
+}
+
+/* item can never get into the AIL */
+STATIC uint
+xfs_icreate_item_push(
+	struct xfs_log_item	*lip,
+	struct list_head	*buffer_list)
+{
+	ASSERT(0);
+	return XFS_ITEM_SUCCESS;
+}
+
+/* Ordered buffers do the dependency tracking here, so this does nothing. */
+STATIC void
+xfs_icreate_item_committing(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+}
+
+/*
+ * This is the ops vector shared by all buf log items.
+ */
+static struct xfs_item_ops xfs_icreate_item_ops = {
+	.iop_size	= xfs_icreate_item_size,
+	.iop_format	= xfs_icreate_item_format,
+	.iop_pin	= xfs_icreate_item_pin,
+	.iop_unpin	= xfs_icreate_item_unpin,
+	.iop_push	= xfs_icreate_item_push,
+	.iop_unlock	= xfs_icreate_item_unlock,
+	.iop_committed	= xfs_icreate_item_committed,
+	.iop_committing = xfs_icreate_item_committing,
+};
+
+
+/*
+ * Initialize the inode log item for a newly allocated (in-core) inode.
+ *
+ * Inode extents can only reside within an AG. Hence specify the starting
+ * block for the inode chunk by offset within an AG as well as the
+ * length of the allocated extent.
+ *
+ * This joins the item to the transaction and marks it dirty so
+ * that we don't need a separate call to do this, nor does the
+ * caller need to know anything about the icreate item.
+ */
+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)
+{
+	struct xfs_icreate_item	*icp;
+
+	icp = kmem_zone_zalloc(xfs_icreate_zone, KM_SLEEP);
+
+	xfs_log_item_init(tp->t_mountp, &icp->ic_item, XFS_LI_ICREATE,
+			  &xfs_icreate_item_ops);
+
+	icp->ic_format.icl_type = XFS_LI_ICREATE;
+	icp->ic_format.icl_size = 1;	/* single vector */
+	icp->ic_format.icl_ag = cpu_to_be32(agno);
+	icp->ic_format.icl_agbno = cpu_to_be32(agbno);
+	icp->ic_format.icl_count = cpu_to_be32(count);
+	icp->ic_format.icl_isize = cpu_to_be32(inode_size);
+	icp->ic_format.icl_length = cpu_to_be32(length);
+	icp->ic_format.icl_gen = cpu_to_be32(generation);
+
+	xfs_trans_add_item(tp, &icp->ic_item);
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	icp->ic_item.li_desc->lid_flags |= XFS_LID_DIRTY;
+}