1 /* $NetBSD: dm_target_error.c,v 1.18 2019/12/08 14:59:42 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 1.18 2019/12/08 14:59:42 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 40 #include <sys/buf.h> 41 42 #include "dm.h" 43 44 /* dm_target_error.c */ 45 int dm_target_error_init(dm_table_entry_t*, char *); 46 char *dm_target_error_status(void *); 47 int dm_target_error_strategy(dm_table_entry_t *, struct buf *); 48 int dm_target_error_sync(dm_table_entry_t *); 49 int dm_target_error_deps(dm_table_entry_t *, prop_array_t); 50 int dm_target_error_destroy(dm_table_entry_t *); 51 int dm_target_error_upcall(dm_table_entry_t *, struct buf *); 52 53 #ifdef DM_TARGET_MODULE 54 /* 55 * Every target can be compiled directly to dm driver or as a 56 * separate module this part of target is used for loading targets 57 * to dm driver. 58 * Target can be unloaded from kernel only if there are no users of 59 * it e.g. there are no devices which uses that target. 60 */ 61 #include <sys/kernel.h> 62 #include <sys/module.h> 63 64 MODULE(MODULE_CLASS_MISC, dm_target_error, "dm"); 65 66 static int 67 dm_target_error_modcmd(modcmd_t cmd, void *arg) 68 { 69 dm_target_t *dmt; 70 int r; 71 dmt = NULL; 72 73 switch (cmd) { 74 case MODULE_CMD_INIT: 75 if ((dmt = dm_target_lookup("error")) != NULL) { 76 dm_target_unbusy(dmt); 77 return EEXIST; 78 } 79 dmt = dm_target_alloc("error"); 80 81 dmt->version[0] = 1; 82 dmt->version[1] = 0; 83 dmt->version[2] = 0; 84 dmt->init = &dm_target_error_init; 85 dmt->status = &dm_target_error_status; 86 dmt->strategy = &dm_target_error_strategy; 87 dmt->sync = &dm_target_error_sync; 88 dmt->deps = &dm_target_error_deps; 89 dmt->destroy = &dm_target_error_destroy; 90 dmt->upcall = &dm_target_error_upcall; 91 dmt->secsize = dm_target_dummy_secsize; 92 93 r = dm_target_insert(dmt); 94 95 break; 96 97 case MODULE_CMD_FINI: 98 r = dm_target_rem("error"); 99 break; 100 101 case MODULE_CMD_STAT: 102 return ENOTTY; 103 104 default: 105 return ENOTTY; 106 } 107 108 return r; 109 } 110 #endif 111 112 /* Init function called from dm_table_load_ioctl. */ 113 int 114 dm_target_error_init(dm_table_entry_t *table_en, char *params) 115 { 116 117 printf("Error target init function called!!\n"); 118 119 table_en->target_config = NULL; 120 121 return 0; 122 } 123 124 /* Status routine called to get params string. */ 125 char * 126 dm_target_error_status(void *target_config) 127 { 128 return NULL; 129 } 130 131 /* Strategy routine called from dm_strategy. */ 132 int 133 dm_target_error_strategy(dm_table_entry_t *table_en, struct buf *bp) 134 { 135 136 printf("Error target read function called!!\n"); 137 138 bp->b_error = EIO; 139 bp->b_resid = 0; 140 141 biodone(bp); 142 143 return 0; 144 } 145 146 /* Sync underlying disk caches. */ 147 int 148 dm_target_error_sync(dm_table_entry_t *table_en) 149 { 150 151 return 0; 152 } 153 154 /* Doesn't do anything here. */ 155 int 156 dm_target_error_destroy(dm_table_entry_t *table_en) 157 { 158 /* Unbusy target so we can unload it */ 159 dm_target_unbusy(table_en->target); 160 161 return 0; 162 } 163 164 /* Doesn't not need to do anything here. */ 165 int 166 dm_target_error_deps(dm_table_entry_t *table_en, prop_array_t prop_array) 167 { 168 return 0; 169 } 170 171 /* Unsupported for this target. */ 172 int 173 dm_target_error_upcall(dm_table_entry_t *table_en, struct buf *bp) 174 { 175 return 0; 176 } 177