1 /* $NetBSD: dm_target_error.c,v 1.24 2019/12/15 14:39:42 tkusumi 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 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: dm_target_error.c,v 1.24 2019/12/15 14:39:42 tkusumi Exp $"); 33 34 /* 35 * This file implements initial version of device-mapper error target. 36 */ 37 #include <sys/types.h> 38 #include <sys/param.h> 39 #include <sys/buf.h> 40 41 #include "dm.h" 42 43 /* dm_target_error.c */ 44 int dm_target_error_init(dm_table_entry_t*, int, char **); 45 char *dm_target_error_table(void *); 46 int dm_target_error_strategy(dm_table_entry_t *, struct buf *); 47 int dm_target_error_deps(dm_table_entry_t *, prop_array_t); 48 int dm_target_error_destroy(dm_table_entry_t *); 49 int dm_target_error_upcall(dm_table_entry_t *, struct buf *); 50 51 #ifdef DM_TARGET_MODULE 52 /* 53 * Every target can be compiled directly to dm driver or as a 54 * separate module this part of target is used for loading targets 55 * to dm driver. 56 * Target can be unloaded from kernel only if there are no users of 57 * it e.g. there are no devices which uses that target. 58 */ 59 #include <sys/kernel.h> 60 #include <sys/module.h> 61 62 MODULE(MODULE_CLASS_MISC, dm_target_error, "dm"); 63 64 static int 65 dm_target_error_modcmd(modcmd_t cmd, void *arg) 66 { 67 dm_target_t *dmt; 68 int r; 69 70 switch (cmd) { 71 case MODULE_CMD_INIT: 72 if ((dmt = dm_target_lookup("error")) != NULL) { 73 dm_target_unbusy(dmt); 74 return EEXIST; 75 } 76 dmt = dm_target_alloc("error"); 77 78 dmt->version[0] = 1; 79 dmt->version[1] = 0; 80 dmt->version[2] = 0; 81 dmt->init = &dm_target_error_init; 82 dmt->table = &dm_target_error_table; 83 dmt->strategy = &dm_target_error_strategy; 84 dmt->deps = &dm_target_error_deps; 85 dmt->destroy = &dm_target_error_destroy; 86 dmt->upcall = &dm_target_error_upcall; 87 88 r = dm_target_insert(dmt); 89 90 break; 91 92 case MODULE_CMD_FINI: 93 r = dm_target_rem("error"); 94 break; 95 96 case MODULE_CMD_STAT: 97 return ENOTTY; 98 99 default: 100 return ENOTTY; 101 } 102 103 return r; 104 } 105 #endif 106 107 /* Init function called from dm_table_load_ioctl. */ 108 int 109 dm_target_error_init(dm_table_entry_t *table_en, int argc, char **argv) 110 { 111 112 printf("Error target init function called!!\n"); 113 114 table_en->target_config = NULL; 115 116 return 0; 117 } 118 119 /* Table routine called to get params string. */ 120 char * 121 dm_target_error_table(void *target_config) 122 { 123 124 return NULL; 125 } 126 127 /* Strategy routine called from dm_strategy. */ 128 int 129 dm_target_error_strategy(dm_table_entry_t *table_en, struct buf *bp) 130 { 131 132 bp->b_error = EIO; 133 bp->b_resid = 0; 134 135 biodone(bp); 136 137 return 0; 138 } 139 140 /* Doesn't do anything here. */ 141 int 142 dm_target_error_destroy(dm_table_entry_t *table_en) 143 { 144 145 /* Unbusy target so we can unload it */ 146 dm_target_unbusy(table_en->target); 147 148 return 0; 149 } 150 151 /* Doesn't not need to do anything here. */ 152 int 153 dm_target_error_deps(dm_table_entry_t *table_en, prop_array_t prop_array) 154 { 155 156 return 0; 157 } 158 159 /* Unsupported for this target. */ 160 int 161 dm_target_error_upcall(dm_table_entry_t *table_en, struct buf *bp) 162 { 163 164 return 0; 165 } 166