Add stubs for mirror target, too. This target does nothing for now, but lvm

tools support mirror target and trying to create LV with mirrorred backend
caused panic in dm_table_load_ioctl.

sys/dev/dm/dm.h

@@ -1,4 +1,4 @@
-/*        $NetBSD: dm.h,v 1.5 2009/01/02 00:42:31 haad Exp $      */
+/*        $NetBSD: dm.h,v 1.6 2009/01/02 11:03:24 haad Exp $      */
 
 /*
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -292,6 +292,14 @@ int dm_target_linear_upcall(dm_table_entry_t *, struct buf *);
 /* Generic function used to convert char to string */
 uint64_t atoi(const char *); 
 
+/* dm_target_mirror.c */
+int dm_target_mirror_init(dm_dev_t *, void**, char *);
+char * dm_target_mirror_status(void *);
+int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *);
+int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t);
+int dm_target_mirror_destroy(dm_table_entry_t *);
+int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *);
+
 /* dm_target_stripe.c */
 int dm_target_stripe_init(dm_dev_t *, void**, char *);
 char * dm_target_stripe_status(void *);

sys/dev/dm/dm_target.c

@@ -1,4 +1,4 @@
-/*        $NetBSD: dm_target.c,v 1.5 2009/01/02 00:42:31 haad Exp $      */
+/*        $NetBSD: dm_target.c,v 1.6 2009/01/02 11:03:24 haad Exp $      */
 
 /*
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -244,7 +244,7 @@ dm_target_prop_list(void)
 int
 dm_target_init(void)
 {
-	dm_target_t *dmt,*dmt3,*dmt4;
+	dm_target_t *dmt,*dmt3;
 	int r;
 
 	r = 0;
@@ -253,7 +253,6 @@ dm_target_init(void)
 	
 	dmt = dm_target_alloc("linear");
 	dmt3 = dm_target_alloc("striped");
-	dmt4 = dm_target_alloc("mirror");
 	
 	dmt->version[0] = 1;
 	dmt->version[1] = 0;
@@ -281,20 +280,8 @@ dm_target_init(void)
 	
 	r = dm_target_insert(dmt3);
 
-	dmt4->version[0] = 1;
-	dmt4->version[1] = 0;
-	dmt4->version[2] = 3;
-	strlcpy(dmt4->name, "mirror", DM_MAX_TYPE_NAME);
-	dmt4->init = NULL;
-	dmt4->status = NULL;
-	dmt4->strategy = NULL;
-	dmt4->deps = NULL;
-	dmt4->destroy = NULL;
-	dmt4->upcall = NULL;
-	
-	r = dm_target_insert(dmt4);
-
-/*	dmt5->version[0] = 1;
+#ifdef notyet	
+	dmt5->version[0] = 1;
 	dmt5->version[1] = 0;
 	dmt5->version[2] = 5;
 	strlcpy(dmt5->name, "snapshot", DM_MAX_TYPE_NAME);
@@ -318,7 +305,8 @@ dm_target_init(void)
 	dmt6->destroy = &dm_target_snapshot_orig_destroy;
 	dmt6->upcall = &dm_target_snapshot_orig_upcall;
 
-	r = dm_target_insert(dmt6);*/
+	r = dm_target_insert(dmt6);
+#endif
 	
 	return r;
 }

sys/dev/dm/dm_target_mirror.c

@@ -0,0 +1,164 @@
+/*$NetBSD: dm_target_mirror.c,v 1.1 2009/01/02 11:03:24 haad Exp $*/
+
+/*
+ * Copyright (c) 2009 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 mirror target.
+ */
+#include <sys/types.h>
+#include <sys/param.h>
+
+#include <sys/buf.h>
+
+#include "dm.h"
+
+#ifdef DM_TARGET_MODULE
+/*
+ * Every target can be compiled directly to dm driver or as a
+ * separate module this part of target is used for loading targets
+ * to dm driver.
+ * Target can be unloaded from kernel only if there are no users of
+ * it e.g. there are no devices which uses that target.
+ */
+#include <sys/kernel.h>
+#include <sys/module.h>
+
+MODULE(MODULE_CLASS_MISC, dm_target_mirror, NULL);
+
+static int
+dm_target_mirror_modcmd(modcmd_t cmd, void *arg)
+{
+	dm_target_t *dmt;
+	int r;
+	dmt = NULL;
+	
+	switch (cmd) {
+	case MODULE_CMD_INIT:
+		if ((r = module_hold("dm")) != 0)
+			return r;
+		
+		if ((dmt = dm_target_lookup("mirror")) != NULL)
+			return EEXIST;
+
+		dmt = dm_target_alloc("mirror");
+		
+		dmt->version[0] = 1;
+		dmt->version[1] = 0;
+		dmt->version[2] = 0;
+		strlcpy(dmt->name, "mirror", DM_MAX_TYPE_NAME);
+		dmt->init = &dm_target_mirror_init;
+		dmt->status = &dm_target_mirror_status;
+		dmt->strategy = &dm_target_mirror_strategy;
+		dmt->deps = &dm_target_mirror_deps;
+		dmt->destroy = &dm_target_mirror_destroy;
+		dmt->upcall = &dm_target_mirror_upcall;
+
+		r = dm_target_insert(dmt);
+		
+		break;
+
+	case MODULE_CMD_FINI:
+		r = dm_target_rem("mirror");
+		module_rele("dm"); /* release usage counter on dm module */
+		break;
+
+	case MODULE_CMD_STAT:
+		return ENOTTY;
+
+	default:
+		return ENOTTY;
+	}
+
+	return r;
+}
+
+#endif
+
+/* Init function called from dm_table_load_ioctl. */
+int
+dm_target_mirror_init(dm_dev_t *dmv, void **target_config, char *argv)
+{
+
+	printf("Mirror target init function called!!\n");
+
+	*target_config = NULL;
+
+	dmv->dev_type = DM_MIRROR_DEV;
+	
+	return 0;
+}
+
+/* Status routine called to get params string. */
+char *
+dm_target_mirror_status(void *target_config)
+{
+	return NULL;
+}	
+
+/* Strategy routine called from dm_strategy. */
+int
+dm_target_mirror_strategy(dm_table_entry_t *table_en, struct buf *bp)
+{
+
+	printf("Mirror target read function called!!\n");
+
+	bp->b_error = EIO;
+	bp->b_resid = 0;
+
+	biodone(bp);
+	
+	return 0;
+}
+
+/* Doesn't do anything here. */
+int
+dm_target_mirror_destroy(dm_table_entry_t *table_en)
+{
+	table_en->target_config = NULL;
+
+	/* Unbusy target so we can unload it */
+	dm_target_unbusy(table_en->target);
+	
+	return 0;
+}
+
+/* Doesn't not need to do anything here. */
+int
+dm_target_mirror_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
+{	
+	return 0;
+}
+
+/* Unsupported for this target. */
+int
+dm_target_mirror_upcall(dm_table_entry_t *table_en, struct buf *bp)
+{
+	return 0;
+}

sys/dev/dm/files.dm

@@ -7,6 +7,7 @@ file        dev/dm/dm_table.c           dm
 file        dev/dm/dm_target.c          dm
 file        dev/dm/dm_target_error.c    dm
 file        dev/dm/dm_target_linear.c   dm
+file        dev/dm/dm_target_mirror.c   dm
 file        dev/dm/dm_target_zero.c     dm
 file 	    dev/dm/dm_target_snapshot.c dm
 file 	    dev/dm/dm_target_stripe.c 	dm

sys/modules/dm/Makefile

@@ -1,4 +1,4 @@
-$NetBSD: Makefile,v 1.3 2009/01/02 01:06:16 haad Exp $
+$NetBSD: Makefile,v 1.4 2009/01/02 11:03:24 haad Exp $
 
 .include "../Makefile.inc"
 
@@ -13,8 +13,9 @@ MK_DM_TARGETS= no
 
 .if (${MK_DM_TARGETS} != "no")
 SUBDIR+= dm_target_error
-SUBDIR+= dm_target_zero
+SUBDIR+= dm_target_mirror
 SUBDIR+= dm_target_snapshot
+SUBDIR+= dm_target_zero
 .endif
 
 .include <bsd.kmodule.mk>

sys/modules/dm/dm_target_mirror/Makefile

@@ -0,0 +1,12 @@
+#$NetBSD: Makefile,v 1.1 2009/01/02 11:03:24 haad Exp $
+
+.include "../../Makefile.inc"
+
+S!=     cd ${.CURDIR}/../../..;pwd
+.PATH:	${S}/dev/dm
+
+CFLAGS += -DDM_TARGET_MODULE
+KMOD=	dm_target_mirror
+SRCS=   dm_target_mirror.c
+
+.include <bsd.kmodule.mk>