1 /*$NetBSD: dm_target_stripe.c,v 1.10 2010/05/18 15:10:41 haad 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 32 /* 33 * This file implements initial version of device-mapper stripe target. 34 */ 35 #include <sys/types.h> 36 #include <sys/param.h> 37 38 #include <sys/buf.h> 39 #include <sys/kmem.h> 40 #include <sys/vnode.h> 41 42 #include "dm.h" 43 44 #ifdef DM_TARGET_MODULE 45 /* 46 * Every target can be compiled directly to dm driver or as a 47 * separate module this part of target is used for loading targets 48 * to dm driver. 49 * Target can be unloaded from kernel only if there are no users of 50 * it e.g. there are no devices which uses that target. 51 */ 52 #include <sys/kernel.h> 53 #include <sys/module.h> 54 55 MODULE(MODULE_CLASS_MISC, dm_target_stripe, NULL); 56 57 static int 58 dm_target_stripe_modcmd(modcmd_t cmd, void *arg) 59 { 60 dm_target_t *dmt; 61 int r; 62 dmt = NULL; 63 64 switch (cmd) { 65 case MODULE_CMD_INIT: 66 if ((dmt = dm_target_lookup("stripe")) != NULL) { 67 dm_target_unbusy(dmt); 68 return EEXIST; 69 } 70 dmt = dm_target_alloc("stripe"); 71 72 dmt->version[0] = 1; 73 dmt->version[1] = 0; 74 dmt->version[2] = 0; 75 strlcpy(dmt->name, "stripe", DM_MAX_TYPE_NAME); 76 dmt->init = &dm_target_stripe_init; 77 dmt->status = &dm_target_stripe_status; 78 dmt->strategy = &dm_target_stripe_strategy; 79 dmt->sync = &dm_target_stripe_sync; 80 dmt->deps = &dm_target_stripe_deps; 81 dmt->destroy = &dm_target_stripe_destroy; 82 dmt->upcall = &dm_target_stripe_upcall; 83 84 r = dm_target_insert(dmt); 85 86 break; 87 88 case MODULE_CMD_FINI: 89 r = dm_target_rem("stripe"); 90 break; 91 92 case MODULE_CMD_STAT: 93 return ENOTTY; 94 95 default: 96 return ENOTTY; 97 } 98 99 return r; 100 } 101 #endif 102 103 /* 104 * Init function called from dm_table_load_ioctl. 105 * Example line sent to dm from lvm tools when using striped target. 106 * start length striped #stripes chunk_size device1 offset1 ... deviceN offsetN 107 * 0 65536 striped 2 512 /dev/hda 0 /dev/hdb 0 108 */ 109 int 110 dm_target_stripe_init(dm_dev_t * dmv, void **target_config, char *params) 111 { 112 dm_target_stripe_config_t *tsc; 113 size_t len; 114 char **ap, *argv[10]; 115 116 if (params == NULL) 117 return EINVAL; 118 119 len = strlen(params) + 1; 120 121 /* 122 * Parse a string, containing tokens delimited by white space, 123 * into an argument vector 124 */ 125 for (ap = argv; ap < &argv[9] && 126 (*ap = strsep(¶ms, " \t")) != NULL;) { 127 if (**ap != '\0') 128 ap++; 129 } 130 131 printf("Stripe target init function called!!\n"); 132 133 printf("Stripe target chunk size %s number of stripes %s\n", argv[1], argv[0]); 134 printf("Stripe target device name %s -- offset %s\n", argv[2], argv[3]); 135 printf("Stripe target device name %s -- offset %s\n", argv[4], argv[5]); 136 137 if (atoi(argv[0]) > MAX_STRIPES) 138 return ENOTSUP; 139 140 if ((tsc = kmem_alloc(sizeof(dm_target_stripe_config_t), KM_NOSLEEP)) 141 == NULL) 142 return ENOMEM; 143 144 /* Insert dmp to global pdev list */ 145 if ((tsc->stripe_devs[0].pdev = dm_pdev_insert(argv[2])) == NULL) 146 return ENOENT; 147 148 /* Insert dmp to global pdev list */ 149 if ((tsc->stripe_devs[1].pdev = dm_pdev_insert(argv[4])) == NULL) 150 return ENOENT; 151 152 tsc->stripe_devs[0].offset = atoi(argv[3]); 153 tsc->stripe_devs[1].offset = atoi(argv[5]); 154 155 /* Save length of param string */ 156 tsc->params_len = len; 157 tsc->stripe_chunksize = atoi(argv[1]); 158 tsc->stripe_num = (uint8_t) atoi(argv[0]); 159 160 *target_config = tsc; 161 162 dmv->dev_type = DM_STRIPE_DEV; 163 164 return 0; 165 } 166 /* Status routine called to get params string. */ 167 char * 168 dm_target_stripe_status(void *target_config) 169 { 170 dm_target_stripe_config_t *tsc; 171 char *params; 172 173 tsc = target_config; 174 175 if ((params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_SLEEP)) == NULL) 176 return NULL; 177 178 snprintf(params, DM_MAX_PARAMS_SIZE, "%d %" PRIu64 " %s %" PRIu64 " %s %" PRIu64, 179 tsc->stripe_num, tsc->stripe_chunksize, 180 tsc->stripe_devs[0].pdev->name, tsc->stripe_devs[0].offset, 181 tsc->stripe_devs[1].pdev->name, tsc->stripe_devs[1].offset); 182 183 return params; 184 } 185 /* Strategy routine called from dm_strategy. */ 186 int 187 dm_target_stripe_strategy(dm_table_entry_t * table_en, struct buf * bp) 188 { 189 dm_target_stripe_config_t *tsc; 190 struct buf *nestbuf; 191 uint64_t blkno, blkoff; 192 uint64_t stripe, stripe_blknr; 193 uint32_t stripe_off, stripe_rest, num_blks, issue_blks; 194 int stripe_devnr; 195 196 tsc = table_en->target_config; 197 if (tsc == NULL) 198 return 0; 199 200 /* printf("Stripe target read function called %" PRIu64 "!!\n", 201 tlc->offset);*/ 202 203 /* calculate extent of request */ 204 KASSERT(bp->b_resid % DEV_BSIZE == 0); 205 206 blkno = bp->b_blkno; 207 blkoff = 0; 208 num_blks = bp->b_resid / DEV_BSIZE; 209 for (;;) { 210 /* blockno to strip piece nr */ 211 stripe = blkno / tsc->stripe_chunksize; 212 stripe_off = blkno % tsc->stripe_chunksize; 213 214 /* where we are inside the strip */ 215 stripe_devnr = stripe % tsc->stripe_num; 216 stripe_blknr = stripe / tsc->stripe_num; 217 218 /* how much is left before we hit a boundary */ 219 stripe_rest = tsc->stripe_chunksize - stripe_off; 220 221 /* issue this piece on stripe `stripe' */ 222 issue_blks = MIN(stripe_rest, num_blks); 223 nestbuf = getiobuf(NULL, true); 224 225 nestiobuf_setup(bp, nestbuf, blkoff, issue_blks * DEV_BSIZE); 226 nestbuf->b_blkno = stripe_blknr * tsc->stripe_chunksize + stripe_off; 227 nestbuf->b_blkno += tsc->stripe_devs[stripe_devnr].offset; 228 229 VOP_STRATEGY(tsc->stripe_devs[stripe_devnr].pdev->pdev_vnode, nestbuf); 230 231 blkno += issue_blks; 232 blkoff += issue_blks * DEV_BSIZE; 233 num_blks -= issue_blks; 234 235 if (num_blks <= 0) 236 break; 237 } 238 239 return 0; 240 } 241 /* Sync underlying disk caches. */ 242 int 243 dm_target_stripe_sync(dm_table_entry_t * table_en) 244 { 245 int cmd, err, i; 246 dm_target_stripe_config_t *tsc; 247 248 tsc = table_en->target_config; 249 250 err = 0; 251 cmd = 1; 252 253 for (i = 0; i < tsc->stripe_num; i++) { 254 if ((err = VOP_IOCTL(tsc->stripe_devs[i].pdev->pdev_vnode, DIOCCACHESYNC, 255 &cmd, FREAD|FWRITE, kauth_cred_get())) != 0) 256 return err; 257 } 258 259 return err; 260 261 } 262 /* Destroy target specific data. */ 263 int 264 dm_target_stripe_destroy(dm_table_entry_t * table_en) 265 { 266 dm_target_stripe_config_t *tsc; 267 268 tsc = table_en->target_config; 269 270 if (tsc == NULL) 271 return 0; 272 273 dm_pdev_decr(tsc->stripe_devs[0].pdev); 274 dm_pdev_decr(tsc->stripe_devs[1].pdev); 275 276 /* Unbusy target so we can unload it */ 277 dm_target_unbusy(table_en->target); 278 279 kmem_free(tsc, sizeof(dm_target_stripe_config_t)); 280 281 table_en->target_config = NULL; 282 283 return 0; 284 } 285 /* Doesn't not need to do anything here. */ 286 int 287 dm_target_stripe_deps(dm_table_entry_t * table_en, prop_array_t prop_array) 288 { 289 dm_target_stripe_config_t *tsc; 290 struct vattr va; 291 292 int error; 293 294 if (table_en->target_config == NULL) 295 return ENOENT; 296 297 tsc = table_en->target_config; 298 299 if ((error = VOP_GETATTR(tsc->stripe_devs[0].pdev->pdev_vnode, &va, curlwp->l_cred)) != 0) 300 return error; 301 302 prop_array_add_uint64(prop_array, (uint64_t) va.va_rdev); 303 304 if ((error = VOP_GETATTR(tsc->stripe_devs[1].pdev->pdev_vnode, &va, curlwp->l_cred)) != 0) 305 return error; 306 307 prop_array_add_uint64(prop_array, (uint64_t) va.va_rdev); 308 309 return 0; 310 } 311 /* Unsupported for this target. */ 312 int 313 dm_target_stripe_upcall(dm_table_entry_t * table_en, struct buf * bp) 314 { 315 return 0; 316 } 317