1 /* $NetBSD: dm_target_zero.c,v 1.2 2008/12/19 15:24:03 haad Exp $ */ 2 3 /* 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Adam Hamsik. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 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. 18 * 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. 30 */ 31 32 33 /* 34 * This file implements initial version of device-mapper zero target. 35 */ 36 #include <sys/types.h> 37 #include <sys/param.h> 38 39 #include <sys/buf.h> 40 41 #include "dm.h" 42 43 /* 44 * Zero target init function. This target doesn't need 45 * target specific config area. 46 */ 47 int 48 dm_target_zero_init(dm_dev_t *dmv, void **target_config, char *argv) 49 { 50 51 printf("Zero target init function called!!\n"); 52 53 dmv->dev_type = DM_ZERO_DEV; 54 55 *target_config = NULL; 56 57 return 0; 58 } 59 60 /* Status routine called to get params string. */ 61 char * 62 dm_target_zero_status(void *target_config) 63 { 64 return NULL; 65 } 66 67 68 /* 69 * This routine does IO operations. 70 */ 71 int 72 dm_target_zero_strategy(dm_table_entry_t *table_en, struct buf *bp) 73 { 74 75 /* printf("Zero target read function called %d!!\n", bp->b_bcount); */ 76 77 memset(bp->b_data, 0, bp->b_bcount); 78 bp->b_resid = 0; /* nestiobuf_done wants b_resid = 0 to be sure 79 that there is no other io to done */ 80 81 biodone(bp); 82 83 return 0; 84 } 85 86 /* Doesn't not need to do anything here. */ 87 int 88 dm_target_zero_destroy(dm_table_entry_t *table_en) 89 { 90 table_en->target_config = NULL; 91 92 return 0; 93 } 94 95 /* Doesn't not need to do anything here. */ 96 int 97 dm_target_zero_deps(dm_table_entry_t *table_en, prop_array_t prop_array) 98 { 99 return 0; 100 } 101 102 /* Unsuported for this target. */ 103 int 104 dm_target_zero_upcall(dm_table_entry_t *table_en, struct buf *bp) 105 { 106 return 0; 107 } 108 109