1 /* $NetBSD: dm_target_linear.c,v 1.9 2010/01/04 00:14:41 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 dklinear target. 35 */ 36 37 #include <dev/disk/dm/dm.h> 38 #include <sys/malloc.h> /* for malloc macros, dm.h includes sys/param.h */ 39 40 MALLOC_DEFINE(M_DMLINEAR, "dm_linear", "Device Mapper Target Linear"); 41 42 typedef struct target_linear_config { 43 dm_pdev_t *pdev; 44 uint64_t offset; 45 } dm_target_linear_config_t; 46 47 /* 48 * Allocate target specific config data, and link them to table. 49 * This function is called only when, flags is not READONLY and 50 * therefore we can add things to pdev list. This should not a 51 * problem because this routine is called only from dm_table_load_ioctl. 52 * @argv[0] is name, 53 * @argv[1] is physical data offset. 54 */ 55 static int 56 dm_target_linear_init(dm_table_entry_t *table_en, int argc, char **argv) 57 { 58 dm_target_linear_config_t *tlc; 59 dm_pdev_t *dmp; 60 61 if (argc != 2) { 62 kprintf("Linear target takes 2 args\n"); 63 return EINVAL; 64 } 65 66 /* Insert dmp to global pdev list */ 67 if ((dmp = dm_pdev_insert(argv[0])) == NULL) 68 return ENOENT; 69 70 if ((tlc = kmalloc(sizeof(dm_target_linear_config_t), M_DMLINEAR, M_WAITOK)) 71 == NULL) 72 return ENOMEM; 73 74 tlc->pdev = dmp; 75 tlc->offset = atoi64(argv[1]); 76 77 dm_table_add_deps(table_en, dmp); 78 79 dm_table_init_target(table_en, tlc); 80 81 return 0; 82 } 83 84 /* 85 * Table routine is called to get params string, which is target 86 * specific. When dm_table_status_ioctl is called with flag 87 * DM_STATUS_TABLE_FLAG I have to sent params string back. 88 */ 89 static char * 90 dm_target_linear_table(void *target_config) 91 { 92 dm_target_linear_config_t *tlc; 93 char *params; 94 tlc = target_config; 95 96 params = dm_alloc_string(DM_MAX_PARAMS_SIZE); 97 98 ksnprintf(params, DM_MAX_PARAMS_SIZE, "%s %" PRIu64, 99 tlc->pdev->udev_name, tlc->offset); 100 101 return params; 102 } 103 104 /* 105 * Do IO operation, called from dmstrategy routine. 106 */ 107 static int 108 dm_target_linear_strategy(dm_table_entry_t *table_en, struct buf *bp) 109 { 110 dm_target_linear_config_t *tlc; 111 112 tlc = table_en->target_config; 113 114 bp->b_bio1.bio_offset += tlc->offset * DEV_BSIZE; 115 116 vn_strategy(tlc->pdev->pdev_vnode, &bp->b_bio1); 117 118 return 0; 119 120 } 121 122 static int 123 dm_target_linear_dump(dm_table_entry_t *table_en, void *data, size_t length, off_t offset) 124 { 125 dm_target_linear_config_t *tlc; 126 127 tlc = table_en->target_config; 128 129 offset += tlc->offset * DEV_BSIZE; 130 offset = dm_pdev_correct_dump_offset(tlc->pdev, offset); 131 132 if (tlc->pdev->pdev_vnode->v_rdev == NULL) 133 return ENXIO; 134 135 return dev_ddump(tlc->pdev->pdev_vnode->v_rdev, data, 0, offset, length); 136 } 137 138 /* 139 * Destroy target specific data. Decrement table pdevs. 140 */ 141 static int 142 dm_target_linear_destroy(dm_table_entry_t *table_en) 143 { 144 dm_target_linear_config_t *tlc; 145 146 /* 147 * Destroy function is called for every target even if it 148 * doesn't have target_config. 149 */ 150 151 if (table_en->target_config == NULL) 152 return 0; 153 154 tlc = table_en->target_config; 155 156 /* Decrement pdev ref counter if 0 remove it */ 157 dm_pdev_decr(tlc->pdev); 158 159 kfree(table_en->target_config, M_DMLINEAR); 160 161 return 0; 162 } 163 164 static int 165 dmtl_mod_handler(module_t mod, int type, void *unused) 166 { 167 dm_target_t *dmt = NULL; 168 int err = 0; 169 170 switch(type) { 171 case MOD_LOAD: 172 if ((dmt = dm_target_lookup("linear")) != NULL) { 173 dm_target_unbusy(dmt); 174 return EEXIST; 175 } 176 dmt = dm_target_alloc("linear"); 177 dmt->version[0] = 1; 178 dmt->version[1] = 0; 179 dmt->version[2] = 2; 180 dmt->init = &dm_target_linear_init; 181 dmt->destroy = &dm_target_linear_destroy; 182 dmt->strategy = &dm_target_linear_strategy; 183 dmt->table = &dm_target_linear_table; 184 dmt->dump = &dm_target_linear_dump; 185 186 err = dm_target_insert(dmt); 187 if (err == 0) 188 kprintf("dm_target_linear: Successfully initialized\n"); 189 break; 190 191 case MOD_UNLOAD: 192 err = dm_target_remove("linear"); 193 if (err == 0) 194 kprintf("dm_target_linear: unloaded\n"); 195 break; 196 } 197 198 return err; 199 } 200 201 DM_TARGET_MODULE(dm_target_linear, dmtl_mod_handler); 202