1 /* $NetBSD: dm_target_zero.c,v 1.10 2010/01/04 00:12:22 haad Exp $ */
4 * Copyright (c) 2008 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
34 * This file implements initial version of device-mapper zero target.
36 #include <sys/types.h>
40 #include <dev/disk/dm/dm.h>
43 * Zero target init function. This target doesn't need
44 * target specific config area.
47 dm_target_zero_init(dm_table_entry_t *table_en, int argc, char **argv)
50 kprintf("Zero target init function called!!\n");
52 dm_table_init_target(table_en, DM_ZERO_DEV, NULL);
58 * This routine does IO operations.
61 dm_target_zero_strategy(dm_table_entry_t *table_en, struct buf *bp)
64 /* kprintf("Zero target read function called %d!!\n", bp->b_bcount); */
66 memset(bp->b_data, 0, bp->b_bcount);
73 /* Doesn't not need to do anything here. */
75 dm_target_zero_destroy(dm_table_entry_t *table_en)
77 table_en->target_config = NULL;
83 dmtz_mod_handler(module_t mod, int type, void *unused)
85 dm_target_t *dmt = NULL;
90 if ((dmt = dm_target_lookup("zero")) != NULL) {
91 dm_target_unbusy(dmt);
94 dmt = dm_target_alloc("zero");
98 strlcpy(dmt->name, "zero", DM_MAX_TYPE_NAME);
99 dmt->init = &dm_target_zero_init;
100 dmt->destroy = &dm_target_zero_destroy;
101 dmt->strategy = &dm_target_zero_strategy;
103 err = dm_target_insert(dmt);
105 kprintf("dm_target_zero: Successfully initialized\n");
109 err = dm_target_rem("zero");
111 kprintf("dm_target_zero: unloaded\n");
121 DM_TARGET_BUILTIN(dm_target_zero, dmtz_mod_handler);