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 <sys/malloc.h> 38 39 #include <dev/disk/dm/dm.h> 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 dmdebug("Linear target init function called %s--%s!!\n", 67 argv[0], argv[1]); 68 69 /* Insert dmp to global pdev list */ 70 if ((dmp = dm_pdev_insert(argv[0])) == NULL) 71 return ENOENT; 72 73 if ((tlc = kmalloc(sizeof(dm_target_linear_config_t), M_DMLINEAR, M_WAITOK)) 74 == NULL) 75 return ENOMEM; 76 77 tlc->pdev = dmp; 78 tlc->offset = atoi64(argv[1]); 79 80 dm_table_add_deps(table_en, dmp); 81 82 dm_table_init_target(table_en, DM_LINEAR_DEV, tlc); 83 84 return 0; 85 } 86 87 /* 88 * Table routine is called to get params string, which is target 89 * specific. When dm_table_status_ioctl is called with flag 90 * DM_STATUS_TABLE_FLAG I have to sent params string back. 91 */ 92 static char * 93 dm_target_linear_table(void *target_config) 94 { 95 dm_target_linear_config_t *tlc; 96 char *params; 97 tlc = target_config; 98 99 dmdebug("Linear target table function called\n"); 100 101 params = dm_alloc_string(DM_MAX_PARAMS_SIZE); 102 103 ksnprintf(params, DM_MAX_PARAMS_SIZE, "%s %" PRIu64, 104 tlc->pdev->udev_name, tlc->offset); 105 106 return params; 107 } 108 109 /* 110 * Do IO operation, called from dmstrategy routine. 111 */ 112 static int 113 dm_target_linear_strategy(dm_table_entry_t *table_en, struct buf *bp) 114 { 115 dm_target_linear_config_t *tlc; 116 117 tlc = table_en->target_config; 118 119 /* kprintf("Linear target read function called %" PRIu64 "!!\n", 120 tlc->offset);*/ 121 122 bp->b_bio1.bio_offset += tlc->offset * DEV_BSIZE; 123 124 vn_strategy(tlc->pdev->pdev_vnode, &bp->b_bio1); 125 126 return 0; 127 128 } 129 130 static int 131 dm_target_linear_dump(dm_table_entry_t *table_en, void *data, size_t length, off_t offset) 132 { 133 dm_target_linear_config_t *tlc; 134 135 tlc = table_en->target_config; 136 137 offset += tlc->offset * DEV_BSIZE; 138 offset = dm_pdev_correct_dump_offset(tlc->pdev, offset); 139 140 if (tlc->pdev->pdev_vnode->v_rdev == NULL) 141 return ENXIO; 142 143 return dev_ddump(tlc->pdev->pdev_vnode->v_rdev, data, 0, offset, length); 144 } 145 146 /* 147 * Destroy target specific data. Decrement table pdevs. 148 */ 149 static int 150 dm_target_linear_destroy(dm_table_entry_t *table_en) 151 { 152 dm_target_linear_config_t *tlc; 153 154 /* 155 * Destroy function is called for every target even if it 156 * doesn't have target_config. 157 */ 158 159 if (table_en->target_config == NULL) 160 return 0; 161 162 tlc = table_en->target_config; 163 164 /* Decrement pdev ref counter if 0 remove it */ 165 dm_pdev_decr(tlc->pdev); 166 167 kfree(table_en->target_config, M_DMLINEAR); 168 169 return 0; 170 } 171 172 static int 173 dmtl_mod_handler(module_t mod, int type, void *unused) 174 { 175 dm_target_t *dmt = NULL; 176 int err = 0; 177 178 switch(type) { 179 case MOD_LOAD: 180 if ((dmt = dm_target_lookup("linear")) != NULL) { 181 dm_target_unbusy(dmt); 182 return EEXIST; 183 } 184 dmt = dm_target_alloc("linear"); 185 dmt->version[0] = 1; 186 dmt->version[1] = 0; 187 dmt->version[2] = 2; 188 dmt->init = &dm_target_linear_init; 189 dmt->destroy = &dm_target_linear_destroy; 190 dmt->strategy = &dm_target_linear_strategy; 191 dmt->table = &dm_target_linear_table; 192 dmt->dump = &dm_target_linear_dump; 193 194 err = dm_target_insert(dmt); 195 if (err == 0) 196 kprintf("dm_target_linear: Successfully initialized\n"); 197 break; 198 199 case MOD_UNLOAD: 200 err = dm_target_remove("linear"); 201 if (err == 0) 202 kprintf("dm_target_linear: unloaded\n"); 203 break; 204 } 205 206 return err; 207 } 208 209 DM_TARGET_MODULE(dm_target_linear, dmtl_mod_handler); 210