geom_io.c revision 93250
1/*- 2 * Copyright (c) 2002 Poul-Henning Kamp 3 * Copyright (c) 2002 Networks Associates Technology, Inc. 4 * All rights reserved. 5 * 6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 7 * and NAI Labs, the Security Research Division of Network Associates, Inc. 8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 9 * DARPA CHATS research program. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The names of the authors may not be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * $FreeBSD: head/sys/geom/geom_io.c 93250 2002-03-26 22:07:38Z phk $ 36 */ 37 38 39#include <sys/param.h> 40#ifndef _KERNEL 41#include <stdio.h> 42#include <string.h> 43#include <stdlib.h> 44#include <signal.h> 45#include <err.h> 46#include <sched.h> 47#else 48#include <sys/systm.h> 49#include <sys/kernel.h> 50#include <sys/malloc.h> 51#include <sys/bio.h> 52#endif 53 54#include <sys/errno.h> 55#include <geom/geom.h> 56#include <geom/geom_int.h> 57 58static struct g_bioq g_bio_run_down; 59static struct g_bioq g_bio_run_up; 60static struct g_bioq g_bio_idle; 61 62#include <machine/atomic.h> 63 64static void 65g_bioq_lock(struct g_bioq *bq) 66{ 67 68 mtx_lock(&bq->bio_queue_lock); 69} 70 71static void 72g_bioq_unlock(struct g_bioq *bq) 73{ 74 75 mtx_unlock(&bq->bio_queue_lock); 76} 77 78#if 0 79static void 80g_bioq_destroy(struct g_bioq *bq) 81{ 82 83 mtx_destroy(&bq->bio_queue_lock); 84} 85#endif 86 87static void 88g_bioq_init(struct g_bioq *bq) 89{ 90 91 TAILQ_INIT(&bq->bio_queue); 92 mtx_init(&bq->bio_queue_lock, "bio queue", MTX_DEF); 93} 94 95static struct bio * 96g_bioq_first(struct g_bioq *bq) 97{ 98 struct bio *bp; 99 100 g_bioq_lock(bq); 101 bp = TAILQ_FIRST(&bq->bio_queue); 102 if (bp != NULL) { 103 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 104 bq->bio_queue_length--; 105 } 106 g_bioq_unlock(bq); 107 return (bp); 108} 109 110static void 111g_bioq_enqueue_tail(struct bio *bp, struct g_bioq *rq) 112{ 113 114 g_bioq_lock(rq); 115 TAILQ_INSERT_TAIL(&rq->bio_queue, bp, bio_queue); 116 rq->bio_queue_length++; 117 g_bioq_unlock(rq); 118} 119 120struct bio * 121g_new_bio(void) 122{ 123 struct bio *bp; 124 125 bp = g_bioq_first(&g_bio_idle); 126 if (bp == NULL) 127 bp = g_malloc(sizeof *bp, M_WAITOK | M_ZERO); 128 g_trace(G_T_BIO, "g_new_bio() = %p", bp); 129 return (bp); 130} 131 132void 133g_destroy_bio(struct bio *bp) 134{ 135 136 g_trace(G_T_BIO, "g_destroy_bio(%p)", bp); 137 bzero(bp, sizeof *bp); 138 g_bioq_enqueue_tail(bp, &g_bio_idle); 139} 140 141struct bio * 142g_clone_bio(struct bio *bp) 143{ 144 struct bio *bp2; 145 146 bp2 = g_new_bio(); 147 bp2->bio_linkage = bp; 148 bp2->bio_cmd = bp->bio_cmd; 149 bp2->bio_length = bp->bio_length; 150 bp2->bio_offset = bp->bio_offset; 151 bp2->bio_data = bp->bio_data; 152 bp2->bio_attribute = bp->bio_attribute; 153 g_trace(G_T_BIO, "g_clone_bio(%p) = %p", bp, bp2); 154 return(bp2); 155} 156 157void 158g_io_init() 159{ 160 161 g_bioq_init(&g_bio_run_down); 162 g_bioq_init(&g_bio_run_up); 163 g_bioq_init(&g_bio_idle); 164} 165 166int 167g_io_setattr(char *attr, struct g_consumer *cp, int len, void *ptr) 168{ 169 struct bio *bp; 170 int error; 171 172 g_trace(G_T_BIO, "bio_setattr(%s)", attr); 173 do { 174 bp = g_new_bio(); 175 bp->bio_cmd = BIO_SETATTR; 176 bp->bio_done = NULL; 177 bp->bio_attribute = attr; 178 bp->bio_length = len; 179 bp->bio_data = ptr; 180 g_io_request(bp, cp); 181 while ((bp->bio_flags & BIO_DONE) == 0) { 182 mtx_lock(&Giant); 183 tsleep(bp, 0, "setattr", hz / 10); 184 mtx_unlock(&Giant); 185 } 186 error = bp->bio_error; 187 g_destroy_bio(bp); 188 if (error == EBUSY) 189 tsleep(&error, 0, "setattr_busy", hz); 190 } while(error == EBUSY); 191 return (error); 192} 193 194 195int 196g_io_getattr(char *attr, struct g_consumer *cp, int *len, void *ptr) 197{ 198 struct bio *bp; 199 int error; 200 201 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 202 do { 203 bp = g_new_bio(); 204 bp->bio_cmd = BIO_GETATTR; 205 bp->bio_done = NULL; 206 bp->bio_attribute = attr; 207 bp->bio_length = *len; 208 bp->bio_data = ptr; 209 g_io_request(bp, cp); 210 while ((bp->bio_flags & BIO_DONE) == 0) { 211 mtx_lock(&Giant); 212 tsleep(bp, 0, "getattr", hz / 10); 213 mtx_unlock(&Giant); 214 } 215 *len = bp->bio_completed; 216 error = bp->bio_error; 217 g_destroy_bio(bp); 218 if (error == EBUSY) 219 tsleep(&error, 0, "getattr_busy", hz); 220 221 } while(error == EBUSY); 222 return (error); 223} 224 225void 226g_io_request(struct bio *bp, struct g_consumer *cp) 227{ 228 int error; 229 230 KASSERT(cp != NULL, ("bio_request on thin air")); 231 error = 0; 232 bp->bio_from = cp; 233 bp->bio_to = cp->provider; 234 235 /* begin_stats(&bp->stats); */ 236 237 atomic_add_int(&cp->biocount, 1); 238 if (bp->bio_to == NULL) 239 error = ENXIO; 240 if (!error) { 241 switch(bp->bio_cmd) { 242 case BIO_READ: 243 case BIO_GETATTR: 244 if (cp->acr == 0) 245 error = EPERM; 246 break; 247 case BIO_WRITE: 248 if (cp->acw == 0) 249 error = EPERM; 250 break; 251 case BIO_SETATTR: 252 case BIO_DELETE: 253 if ((cp->acw == 0) || (cp->ace == 0)) 254 error = EPERM; 255 break; 256 default: 257 error = EPERM; 258 break; 259 } 260 } 261 /* if provider is marked for error, don't disturb */ 262 if (!error) 263 error = bp->bio_to->error; 264 if (error) { 265 bp->bio_error = error; 266 /* finish_stats(&bp->stats); */ 267 268 g_trace(G_T_BIO, 269 "bio_request(%p) from %p(%s) to %p(%s) cmd %d error %d\n", 270 bp, bp->bio_from, bp->bio_from->geom->name, 271 bp->bio_to, bp->bio_to->name, bp->bio_cmd, bp->bio_error); 272 g_bioq_enqueue_tail(bp, &g_bio_run_up); 273 mtx_lock(&Giant); 274 wakeup(&g_wait_up); 275 mtx_unlock(&Giant); 276 } else { 277 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 278 bp, bp->bio_from, bp->bio_from->geom->name, 279 bp->bio_to, bp->bio_to->name, bp->bio_cmd); 280 g_bioq_enqueue_tail(bp, &g_bio_run_down); 281 mtx_lock(&Giant); 282 wakeup(&g_wait_down); 283 mtx_unlock(&Giant); 284 } 285} 286 287void 288g_io_deliver(struct bio *bp) 289{ 290 291 g_trace(G_T_BIO, 292 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d", 293 bp, bp->bio_from, bp->bio_from->geom->name, 294 bp->bio_to, bp->bio_to->name, bp->bio_cmd, bp->bio_error); 295 /* finish_stats(&bp->stats); */ 296 297 g_bioq_enqueue_tail(bp, &g_bio_run_up); 298 299 mtx_lock(&Giant); 300 wakeup(&g_wait_up); 301 mtx_unlock(&Giant); 302} 303 304void 305g_io_schedule_down(struct thread *tp __unused) 306{ 307 struct bio *bp; 308 309 for(;;) { 310 bp = g_bioq_first(&g_bio_run_down); 311 if (bp == NULL) 312 break; 313 bp->bio_to->geom->start(bp); 314 } 315} 316 317void 318g_io_schedule_up(struct thread *tp __unused) 319{ 320 struct bio *bp; 321 struct g_consumer *cp; 322 323 for(;;) { 324 bp = g_bioq_first(&g_bio_run_up); 325 if (bp == NULL) 326 break; 327 328 cp = bp->bio_from; 329 330 bp->bio_flags |= BIO_DONE; 331 atomic_add_int(&cp->biocount, -1); 332 if (bp->bio_done != NULL) { 333 bp->bio_done(bp); 334 } else { 335 mtx_lock(&Giant); 336 wakeup(bp); 337 mtx_unlock(&Giant); 338 } 339 } 340} 341 342void * 343g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 344{ 345 struct bio *bp; 346 void *ptr; 347 int errorc; 348 349 do { 350 bp = g_new_bio(); 351 bp->bio_cmd = BIO_READ; 352 bp->bio_done = NULL; 353 bp->bio_offset = offset; 354 bp->bio_length = length; 355 ptr = g_malloc(length, M_WAITOK); 356 bp->bio_data = ptr; 357 g_io_request(bp, cp); 358 while ((bp->bio_flags & BIO_DONE) == 0) { 359 mtx_lock(&Giant); 360 tsleep(bp, 0, "g_read_data", hz / 10); 361 mtx_unlock(&Giant); 362 } 363 errorc = bp->bio_error; 364 if (error != NULL) 365 *error = errorc; 366 g_destroy_bio(bp); 367 if (errorc) { 368 g_free(ptr); 369 ptr = NULL; 370 } 371 if (errorc == EBUSY) 372 tsleep(&errorc, 0, "g_read_data_busy", hz); 373 } while (errorc == EBUSY); 374 return (ptr); 375} 376