1 /* $NetBSD: dm_target_error.c,v 1.5 2009/01/02 11:06:17 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 * This file implements initial version of device-mapper error target. 34 */ 35 #include <sys/types.h> 36 #include <sys/param.h> 37 38 #include <sys/buf.h> 39 40 #include "dm.h" 41 42 #ifdef DM_TARGET_MODULE 43 /* 44 * Every target can be compiled directly to dm driver or as a 45 * separate module this part of target is used for loading targets 46 * to dm driver. 47 * Target can be unloaded from kernel only if there are no users of 48 * it e.g. there are no devices which uses that target. 49 */ 50 #include <sys/kernel.h> 51 #include <sys/module.h> 52 53 MODULE(MODULE_CLASS_MISC, dm_target_error, NULL); 54 55 static int 56 dm_target_error_modcmd(modcmd_t cmd, void *arg) 57 { 58 dm_target_t *dmt; 59 int r; 60 dmt = NULL; 61 62 switch (cmd) { 63 case MODULE_CMD_INIT: 64 if ((r = module_hold("dm")) != 0) 65 return r; 66 67 if ((dmt = dm_target_lookup("error")) != NULL) 68 return EEXIST; 69 70 dmt = dm_target_alloc("error"); 71 72 dmt->version[0] = 1; 73 dmt->version[1] = 0; 74 dmt->version[2] = 0; 75 strlcpy(dmt->name, "error", DM_MAX_TYPE_NAME); 76 dmt->init = &dm_target_error_init; 77 dmt->status = &dm_target_error_status; 78 dmt->strategy = &dm_target_error_strategy; 79 dmt->deps = &dm_target_error_deps; 80 dmt->destroy = &dm_target_error_destroy; 81 dmt->upcall = &dm_target_error_upcall; 82 83 r = dm_target_insert(dmt); 84 85 break; 86 87 case MODULE_CMD_FINI: 88 r = dm_target_rem("error"); 89 module_rele("dm"); /* release usage counter on dm module */ 90 91 break; 92 93 case MODULE_CMD_STAT: 94 return ENOTTY; 95 96 default: 97 return ENOTTY; 98 } 99 100 return r; 101 } 102 103 #endif 104 105 /* Init function called from dm_table_load_ioctl. */ 106 int 107 dm_target_error_init(dm_dev_t *dmv, void **target_config, char *argv) 108 { 109 110 printf("Error target init function called!!\n"); 111 112 *target_config = NULL; 113 114 dmv->dev_type = DM_ERROR_DEV; 115 116 return 0; 117 } 118 119 /* Status routine called to get params string. */ 120 char * 121 dm_target_error_status(void *target_config) 122 { 123 return NULL; 124 } 125 126 /* Strategy routine called from dm_strategy. */ 127 int 128 dm_target_error_strategy(dm_table_entry_t *table_en, struct buf *bp) 129 { 130 131 printf("Error target read function called!!\n"); 132 133 bp->b_error = EIO; 134 bp->b_resid = 0; 135 136 biodone(bp); 137 138 return 0; 139 } 140 141 /* Doesn't do anything here. */ 142 int 143 dm_target_error_destroy(dm_table_entry_t *table_en) 144 { 145 table_en->target_config = NULL; 146 147 /* Unbusy target so we can unload it */ 148 dm_target_unbusy(table_en->target); 149 150 return 0; 151 } 152 153 /* Doesn't not need to do anything here. */ 154 int 155 dm_target_error_deps(dm_table_entry_t *table_en, prop_array_t prop_array) 156 { 157 return 0; 158 } 159 160 /* Unsupported for this target. */ 161 int 162 dm_target_error_upcall(dm_table_entry_t *table_en, struct buf *bp) 163 { 164 return 0; 165 } 166