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Diffstat (limited to 'sys/dev/dm/dm_target_zero.c')
-rw-r--r--sys/dev/dm/dm_target_zero.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/sys/dev/dm/dm_target_zero.c b/sys/dev/dm/dm_target_zero.c
new file mode 100644
index 00000000000..b2defff836c
--- /dev/null
+++ b/sys/dev/dm/dm_target_zero.c
@@ -0,0 +1,108 @@
+/* $NetBSD: dm_target_zero.c,v 1.2 2008/12/19 15:24:03 haad Exp $ */
+
+/*
+ * Copyright (c) 2008 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Adam Hamsik.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+/*
+ * This file implements initial version of device-mapper zero target.
+ */
+#include <sys/types.h>
+#include <sys/param.h>
+
+#include <sys/buf.h>
+
+#include "dm.h"
+
+/*
+ * Zero target init function. This target doesn't need
+ * target specific config area.
+ */
+int
+dm_target_zero_init(dm_dev_t *dmv, void **target_config, char *argv)
+{
+
+ printf("Zero target init function called!!\n");
+
+ dmv->dev_type = DM_ZERO_DEV;
+
+ *target_config = NULL;
+
+ return 0;
+}
+
+/* Status routine called to get params string. */
+char *
+dm_target_zero_status(void *target_config)
+{
+ return NULL;
+}
+
+
+/*
+ * This routine does IO operations.
+ */
+int
+dm_target_zero_strategy(dm_table_entry_t *table_en, struct buf *bp)
+{
+
+ /* printf("Zero target read function called %d!!\n", bp->b_bcount); */
+
+ memset(bp->b_data, 0, bp->b_bcount);
+ bp->b_resid = 0; /* nestiobuf_done wants b_resid = 0 to be sure
+ that there is no other io to done */
+
+ biodone(bp);
+
+ return 0;
+}
+
+/* Doesn't not need to do anything here. */
+int
+dm_target_zero_destroy(dm_table_entry_t *table_en)
+{
+ table_en->target_config = NULL;
+
+ return 0;
+}
+
+/* Doesn't not need to do anything here. */
+int
+dm_target_zero_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
+{
+ return 0;
+}
+
+/* Unsuported for this target. */
+int
+dm_target_zero_upcall(dm_table_entry_t *table_en, struct buf *bp)
+{
+ return 0;
+}
+