dm_target_mirror.c revision 1.22
1 /*$NetBSD: dm_target_mirror.c,v 1.22 2019/12/15 14:39:42 tkusumi Exp $*/ 2 3 /* 4 * Copyright (c) 2009 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Adam Hamsik. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: dm_target_mirror.c,v 1.22 2019/12/15 14:39:42 tkusumi Exp $"); 33 34 /* 35 * This file implements initial version of device-mapper mirror 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_mirror.c */ 44 int dm_target_mirror_init(dm_table_entry_t *, int, char **); 45 char *dm_target_mirror_table(void *); 46 int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *); 47 int dm_target_mirror_sync(dm_table_entry_t *); 48 int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t); 49 int dm_target_mirror_destroy(dm_table_entry_t *); 50 int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *); 51 52 typedef struct target_mirror_config { 53 #define MAX_MIRROR_COPIES 4 54 dm_pdev_t *orig; 55 dm_pdev_t *copies[MAX_MIRROR_COPIES]; 56 57 /* copied blocks bitmaps administration etc*/ 58 dm_pdev_t *log_pdev; /* for administration */ 59 uint64_t log_regionsize; /* blocksize of mirror */ 60 61 /* list of parts that still need copied etc.; run length encoded? */ 62 } dm_target_mirror_config_t; 63 64 #ifdef DM_TARGET_MODULE 65 /* 66 * Every target can be compiled directly to dm driver or as a 67 * separate module this part of target is used for loading targets 68 * to dm driver. 69 * Target can be unloaded from kernel only if there are no users of 70 * it e.g. there are no devices which uses that target. 71 */ 72 #include <sys/kernel.h> 73 #include <sys/module.h> 74 75 MODULE(MODULE_CLASS_MISC, dm_target_mirror, "dm"); 76 77 static int 78 dm_target_mirror_modcmd(modcmd_t cmd, void *arg) 79 { 80 dm_target_t *dmt; 81 int r; 82 83 switch (cmd) { 84 case MODULE_CMD_INIT: 85 if ((dmt = dm_target_lookup("mirror")) != NULL) { 86 dm_target_unbusy(dmt); 87 return EEXIST; 88 } 89 dmt = dm_target_alloc("mirror"); 90 91 dmt->version[0] = 1; 92 dmt->version[1] = 0; 93 dmt->version[2] = 0; 94 dmt->init = &dm_target_mirror_init; 95 dmt->table = &dm_target_mirror_table; 96 dmt->strategy = &dm_target_mirror_strategy; 97 dmt->sync = &dm_target_mirror_sync; 98 dmt->deps = &dm_target_mirror_deps; 99 dmt->destroy = &dm_target_mirror_destroy; 100 dmt->upcall = &dm_target_mirror_upcall; 101 102 r = dm_target_insert(dmt); 103 104 break; 105 106 case MODULE_CMD_FINI: 107 r = dm_target_rem("mirror"); 108 break; 109 110 case MODULE_CMD_STAT: 111 return ENOTTY; 112 113 default: 114 return ENOTTY; 115 } 116 117 return r; 118 } 119 #endif 120 121 /* 122 * Init function called from dm_table_load_ioctl. 123 * start length mirror log_type #logargs logarg1 ... logargN #devs device1 offset1 ... deviceN offsetN 124 * 0 52428800 mirror clustered_disk 4 253:2 1024 UUID block_on_error 3 253:3 0 253:4 0 253:5 0 125 */ 126 int 127 dm_target_mirror_init(dm_table_entry_t *table_en, int argc, char **argv) 128 { 129 130 printf("Mirror target init function called!!\n"); 131 132 table_en->target_config = NULL; 133 134 return ENOSYS; 135 } 136 137 /* Table routine called to get params string. */ 138 char * 139 dm_target_mirror_table(void *target_config) 140 { 141 142 return NULL; 143 } 144 145 /* Strategy routine called from dm_strategy. */ 146 int 147 dm_target_mirror_strategy(dm_table_entry_t *table_en, struct buf *bp) 148 { 149 150 bp->b_error = EIO; 151 bp->b_resid = 0; 152 153 biodone(bp); 154 155 return 0; 156 } 157 158 /* Sync underlying disk caches. */ 159 int 160 dm_target_mirror_sync(dm_table_entry_t *table_en) 161 { 162 163 return 0; 164 } 165 166 /* Doesn't do anything here. */ 167 int 168 dm_target_mirror_destroy(dm_table_entry_t *table_en) 169 { 170 171 /* Unbusy target so we can unload it */ 172 dm_target_unbusy(table_en->target); 173 174 return 0; 175 } 176 177 /* Doesn't not need to do anything here. */ 178 int 179 dm_target_mirror_deps(dm_table_entry_t *table_en, prop_array_t prop_array) 180 { 181 182 return 0; 183 } 184 185 /* Unsupported for this target. */ 186 int 187 dm_target_mirror_upcall(dm_table_entry_t *table_en, struct buf *bp) 188 { 189 190 return 0; 191 } 192
Indexes created Thu Oct 02 01:09:59 GMT 2025