1 /* $NetBSD: dm_target_linear.c,v 1.17 2018/01/05 14:22:05 christos 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_linear.c,v 1.17 2018/01/05 14:22:05 christos Exp $"); 33 34 /* 35 * This file implements initial version of device-mapper dklinear target. 36 */ 37 38 #include <sys/types.h> 39 #include <sys/param.h> 40 41 #include <sys/buf.h> 42 #include <sys/kmem.h> 43 #include <sys/vnode.h> 44 #include <sys/lwp.h> 45 46 #include <machine/int_fmtio.h> 47 48 #include "dm.h" 49 50 /* 51 * Allocate target specific config data, and link them to table. 52 * This function is called only when, flags is not READONLY and 53 * therefore we can add things to pdev list. This should not a 54 * problem because this routine is called only from dm_table_load_ioctl. 55 * @argv[0] is name, 56 * @argv[1] is physical data offset. 57 */ 58 int 59 dm_target_linear_init(dm_dev_t * dmv, void **target_config, char *params) 60 { 61 dm_target_linear_config_t *tlc; 62 dm_pdev_t *dmp; 63 64 char **ap, *argv[3]; 65 66 if (params == NULL) 67 return EINVAL; 68 69 /* 70 * Parse a string, containing tokens delimited by white space, 71 * into an argument vector 72 */ 73 for (ap = argv; ap < &argv[2] && 74 (*ap = strsep(¶ms, " \t")) != NULL;) { 75 if (**ap != '\0') 76 ap++; 77 } 78 79 aprint_debug("Linear target init function called %s--%s!!\n", 80 argv[0], argv[1]); 81 82 /* Insert dmp to global pdev list */ 83 if ((dmp = dm_pdev_insert(argv[0])) == NULL) 84 return ENOENT; 85 86 tlc = kmem_alloc(sizeof(dm_target_linear_config_t), KM_SLEEP); 87 tlc->pdev = dmp; 88 tlc->offset = 0; /* default settings */ 89 90 /* Check user input if it is not leave offset as 0. */ 91 tlc->offset = atoi(argv[1]); 92 93 *target_config = tlc; 94 95 dmv->dev_type = DM_LINEAR_DEV; 96 97 return 0; 98 } 99 100 /* 101 * Status routine is called to get params string, which is target 102 * specific. When dm_table_status_ioctl is called with flag 103 * DM_STATUS_TABLE_FLAG I have to sent params string back. 104 */ 105 char * 106 dm_target_linear_status(void *target_config) 107 { 108 dm_target_linear_config_t *tlc; 109 char *params; 110 tlc = target_config; 111 112 aprint_debug("Linear target status function called\n"); 113 114 if ((params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_NOSLEEP)) == NULL) 115 return NULL; 116 117 aprint_normal("%s %" PRIu64, tlc->pdev->name, tlc->offset); 118 snprintf(params, DM_MAX_PARAMS_SIZE, "%s %" PRIu64, 119 tlc->pdev->name, tlc->offset); 120 121 return params; 122 } 123 124 /* 125 * Do IO operation, called from dmstrategy routine. 126 */ 127 int 128 dm_target_linear_strategy(dm_table_entry_t * table_en, struct buf * bp) 129 { 130 dm_target_linear_config_t *tlc; 131 132 tlc = table_en->target_config; 133 134 /* printf("Linear target read function called %" PRIu64 "!!\n", 135 tlc->offset);*/ 136 137 bp->b_blkno += tlc->offset; 138 139 VOP_STRATEGY(tlc->pdev->pdev_vnode, bp); 140 141 return 0; 142 143 } 144 145 /* 146 * Sync underlying disk caches. 147 */ 148 int 149 dm_target_linear_sync(dm_table_entry_t * table_en) 150 { 151 int cmd; 152 dm_target_linear_config_t *tlc; 153 154 tlc = table_en->target_config; 155 156 cmd = 1; 157 158 return VOP_IOCTL(tlc->pdev->pdev_vnode, DIOCCACHESYNC, &cmd, 159 FREAD|FWRITE, kauth_cred_get()); 160 } 161 162 /* 163 * Destroy target specific data. Decrement table pdevs. 164 */ 165 int 166 dm_target_linear_destroy(dm_table_entry_t * table_en) 167 { 168 169 /* 170 * Destroy function is called for every target even if it 171 * doesn't have target_config. 172 */ 173 if (table_en->target_config == NULL) 174 goto out; 175 176 dm_target_linear_config_t *tlc = table_en->target_config; 177 table_en->target_config = NULL; 178 179 /* Decrement pdev ref counter if 0 remove it */ 180 dm_pdev_decr(tlc->pdev); 181 182 kmem_free(tlc, sizeof(*tlc)); 183 184 out: 185 /* Unbusy target so we can unload it */ 186 dm_target_unbusy(table_en->target); 187 return 0; 188 } 189 190 /* Add this target pdev dependencies to prop_array_t */ 191 int 192 dm_target_linear_deps(dm_table_entry_t * table_en, prop_array_t prop_array) 193 { 194 dm_target_linear_config_t *tlc; 195 196 if (table_en->target_config == NULL) 197 return ENOENT; 198 199 tlc = table_en->target_config; 200 201 prop_array_add_uint64(prop_array, 202 (uint64_t) tlc->pdev->pdev_vnode->v_rdev); 203 204 return 0; 205 } 206 207 /* 208 * Register upcall device. 209 * Linear target doesn't need any upcall devices but other targets like 210 * mirror, snapshot, multipath, stripe will use this functionality. 211 */ 212 int 213 dm_target_linear_upcall(dm_table_entry_t * table_en, struct buf * bp) 214 { 215 return 0; 216 } 217 218 /* 219 * Query physical block size of this target 220 * For a linear target this is just the sector size of the underlying device 221 */ 222 int 223 dm_target_linear_secsize(dm_table_entry_t * table_en, unsigned *secsizep) 224 { 225 dm_target_linear_config_t *tlc; 226 unsigned secsize; 227 228 secsize = 0; 229 230 tlc = table_en->target_config; 231 if (tlc != NULL) 232 secsize = tlc->pdev->pdev_secsize; 233 234 *secsizep = secsize; 235 236 return 0; 237 } 238 239 /* 240 * Transform char s to uint64_t offset number. 241 */ 242 uint64_t 243 atoi(const char *s) 244 { 245 uint64_t n; 246 n = 0; 247 248 while (*s != '\0') { 249 if (!isdigit(*s)) 250 break; 251 252 n = (10 * n) + (*s - '0'); 253 s++; 254 } 255 256 return n; 257 } 258