geom_io.c revision 130280
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 36#include <sys/cdefs.h> 37__FBSDID("$FreeBSD: head/sys/geom/geom_io.c 130280 2004-06-09 19:44:44Z phk $"); 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/kernel.h> 42#include <sys/malloc.h> 43#include <sys/bio.h> 44 45#include <sys/errno.h> 46#include <geom/geom.h> 47#include <geom/geom_int.h> 48#include <sys/devicestat.h> 49 50#include <vm/uma.h> 51 52static struct g_bioq g_bio_run_down; 53static struct g_bioq g_bio_run_up; 54static struct g_bioq g_bio_run_task; 55 56static u_int pace; 57static uma_zone_t biozone; 58 59#include <machine/atomic.h> 60 61static void 62g_bioq_lock(struct g_bioq *bq) 63{ 64 65 mtx_lock(&bq->bio_queue_lock); 66} 67 68static void 69g_bioq_unlock(struct g_bioq *bq) 70{ 71 72 mtx_unlock(&bq->bio_queue_lock); 73} 74 75#if 0 76static void 77g_bioq_destroy(struct g_bioq *bq) 78{ 79 80 mtx_destroy(&bq->bio_queue_lock); 81} 82#endif 83 84static void 85g_bioq_init(struct g_bioq *bq) 86{ 87 88 TAILQ_INIT(&bq->bio_queue); 89 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 90} 91 92static struct bio * 93g_bioq_first(struct g_bioq *bq) 94{ 95 struct bio *bp; 96 97 bp = TAILQ_FIRST(&bq->bio_queue); 98 if (bp != NULL) { 99 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 100 bq->bio_queue_length--; 101 } 102 return (bp); 103} 104 105static void 106g_bioq_enqueue_tail(struct bio *bp, struct g_bioq *rq) 107{ 108 109 g_bioq_lock(rq); 110 TAILQ_INSERT_TAIL(&rq->bio_queue, bp, bio_queue); 111 rq->bio_queue_length++; 112 g_bioq_unlock(rq); 113} 114 115struct bio * 116g_new_bio(void) 117{ 118 struct bio *bp; 119 120 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 121 return (bp); 122} 123 124void 125g_destroy_bio(struct bio *bp) 126{ 127 128 uma_zfree(biozone, bp); 129} 130 131struct bio * 132g_clone_bio(struct bio *bp) 133{ 134 struct bio *bp2; 135 136 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 137 if (bp2 != NULL) { 138 bp2->bio_parent = bp; 139 bp2->bio_cmd = bp->bio_cmd; 140 bp2->bio_length = bp->bio_length; 141 bp2->bio_offset = bp->bio_offset; 142 bp2->bio_data = bp->bio_data; 143 bp2->bio_attribute = bp->bio_attribute; 144 bp->bio_children++; 145 } 146 return(bp2); 147} 148 149void 150g_io_init() 151{ 152 153 g_bioq_init(&g_bio_run_down); 154 g_bioq_init(&g_bio_run_up); 155 g_bioq_init(&g_bio_run_task); 156 biozone = uma_zcreate("g_bio", sizeof (struct bio), 157 NULL, NULL, 158 NULL, NULL, 159 0, 0); 160} 161 162int 163g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 164{ 165 struct bio *bp; 166 int error; 167 168 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 169 bp = g_new_bio(); 170 bp->bio_cmd = BIO_GETATTR; 171 bp->bio_done = NULL; 172 bp->bio_attribute = attr; 173 bp->bio_length = *len; 174 bp->bio_data = ptr; 175 g_io_request(bp, cp); 176 error = biowait(bp, "ggetattr"); 177 *len = bp->bio_completed; 178 g_destroy_bio(bp); 179 return (error); 180} 181 182static int 183g_io_check(struct bio *bp) 184{ 185 struct g_consumer *cp; 186 struct g_provider *pp; 187 188 cp = bp->bio_from; 189 pp = bp->bio_to; 190 191 /* Fail if access counters dont allow the operation */ 192 switch(bp->bio_cmd) { 193 case BIO_READ: 194 case BIO_GETATTR: 195 if (cp->acr == 0) 196 return (EPERM); 197 break; 198 case BIO_WRITE: 199 case BIO_DELETE: 200 if (cp->acw == 0) 201 return (EPERM); 202 break; 203 default: 204 return (EPERM); 205 } 206 /* if provider is marked for error, don't disturb. */ 207 if (pp->error) 208 return (pp->error); 209 210 switch(bp->bio_cmd) { 211 case BIO_READ: 212 case BIO_WRITE: 213 case BIO_DELETE: 214 /* Zero sectorsize is a probably lack of media */ 215 if (pp->sectorsize == 0) 216 return (ENXIO); 217 /* Reject I/O not on sector boundary */ 218 if (bp->bio_offset % pp->sectorsize) 219 return (EINVAL); 220 /* Reject I/O not integral sector long */ 221 if (bp->bio_length % pp->sectorsize) 222 return (EINVAL); 223 /* Reject requests before or past the end of media. */ 224 if (bp->bio_offset < 0) 225 return (EIO); 226 if (bp->bio_offset > pp->mediasize) 227 return (EIO); 228 break; 229 default: 230 break; 231 } 232 return (0); 233} 234 235void 236g_io_request(struct bio *bp, struct g_consumer *cp) 237{ 238 struct g_provider *pp; 239 240 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 241 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 242 KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request")); 243 pp = cp->provider; 244 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 245 246 bp->bio_from = cp; 247 bp->bio_to = pp; 248 bp->bio_error = 0; 249 bp->bio_completed = 0; 250 251 if (g_collectstats & 1) 252 devstat_start_transaction_bio(pp->stat, bp); 253 pp->nstart++; 254 if (g_collectstats & 2) 255 devstat_start_transaction_bio(cp->stat, bp); 256 cp->nstart++; 257 258 /* Pass it on down. */ 259 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 260 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 261 g_bioq_enqueue_tail(bp, &g_bio_run_down); 262 wakeup(&g_wait_down); 263} 264 265void 266g_io_deliver(struct bio *bp, int error) 267{ 268 struct g_consumer *cp; 269 struct g_provider *pp; 270 271 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 272 pp = bp->bio_to; 273 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 274 cp = bp->bio_from; 275 if (cp == NULL) { 276 bp->bio_error = error; 277 bp->bio_done(bp); 278 return; 279 } 280 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 281 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 282 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 283 KASSERT(bp->bio_completed <= bp->bio_length, 284 ("bio_completed can't be greater than bio_length")); 285 286 g_trace(G_T_BIO, 287"g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 288 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 289 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 290 291 bp->bio_bcount = bp->bio_length; 292 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 293 if (g_collectstats & 1) 294 devstat_end_transaction_bio(pp->stat, bp); 295 if (g_collectstats & 2) 296 devstat_end_transaction_bio(cp->stat, bp); 297 cp->nend++; 298 pp->nend++; 299 300 if (error == ENOMEM) { 301 if (bootverbose) 302 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 303 g_io_request(bp, cp); 304 pace++; 305 return; 306 } 307 bp->bio_error = error; 308 g_bioq_enqueue_tail(bp, &g_bio_run_up); 309 wakeup(&g_wait_up); 310} 311 312void 313g_io_schedule_down(struct thread *tp __unused) 314{ 315 struct bio *bp; 316 off_t excess; 317 int error; 318 struct mtx mymutex; 319 320 bzero(&mymutex, sizeof mymutex); 321 mtx_init(&mymutex, "g_xdown", NULL, MTX_DEF); 322 323 for(;;) { 324 g_bioq_lock(&g_bio_run_down); 325 bp = g_bioq_first(&g_bio_run_down); 326 if (bp == NULL) { 327 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 328 PRIBIO | PDROP, "-", hz/10); 329 continue; 330 } 331 g_bioq_unlock(&g_bio_run_down); 332 if (pace > 0) { 333 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 334 pace--; 335 } 336 error = g_io_check(bp); 337 if (error) { 338 g_io_deliver(bp, error); 339 continue; 340 } 341 switch (bp->bio_cmd) { 342 case BIO_READ: 343 case BIO_WRITE: 344 case BIO_DELETE: 345 /* Truncate requests to the end of providers media. */ 346 excess = bp->bio_offset + bp->bio_length; 347 if (excess > bp->bio_to->mediasize) { 348 excess -= bp->bio_to->mediasize; 349 bp->bio_length -= excess; 350 } 351 /* Deliver zero length transfers right here. */ 352 if (bp->bio_length == 0) { 353 g_io_deliver(bp, 0); 354 continue; 355 } 356 break; 357 default: 358 break; 359 } 360 mtx_lock(&mymutex); 361 bp->bio_to->geom->start(bp); 362 mtx_unlock(&mymutex); 363 } 364} 365 366void 367bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg) 368{ 369 bp->bio_task = func; 370 bp->bio_task_arg = arg; 371 /* 372 * The taskqueue is actually just a second queue off the "up" 373 * queue, so we use the same lock. 374 */ 375 g_bioq_lock(&g_bio_run_up); 376 TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue); 377 g_bio_run_task.bio_queue_length++; 378 wakeup(&g_wait_up); 379 g_bioq_unlock(&g_bio_run_up); 380} 381 382 383void 384g_io_schedule_up(struct thread *tp __unused) 385{ 386 struct bio *bp; 387 struct mtx mymutex; 388 389 bzero(&mymutex, sizeof mymutex); 390 mtx_init(&mymutex, "g_xup", NULL, MTX_DEF); 391 for(;;) { 392 g_bioq_lock(&g_bio_run_up); 393 bp = g_bioq_first(&g_bio_run_task); 394 if (bp != NULL) { 395 g_bioq_unlock(&g_bio_run_up); 396 mtx_lock(&mymutex); 397 bp->bio_task(bp->bio_task_arg); 398 mtx_unlock(&mymutex); 399 continue; 400 } 401 bp = g_bioq_first(&g_bio_run_up); 402 if (bp != NULL) { 403 g_bioq_unlock(&g_bio_run_up); 404 mtx_lock(&mymutex); 405 biodone(bp); 406 mtx_unlock(&mymutex); 407 continue; 408 } 409 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 410 PRIBIO | PDROP, "-", hz/10); 411 } 412} 413 414void * 415g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 416{ 417 struct bio *bp; 418 void *ptr; 419 int errorc; 420 421 KASSERT(length >= 512 && length <= DFLTPHYS, 422 ("g_read_data(): invalid length %jd", (intmax_t)length)); 423 424 bp = g_new_bio(); 425 bp->bio_cmd = BIO_READ; 426 bp->bio_done = NULL; 427 bp->bio_offset = offset; 428 bp->bio_length = length; 429 ptr = g_malloc(length, M_WAITOK); 430 bp->bio_data = ptr; 431 g_io_request(bp, cp); 432 errorc = biowait(bp, "gread"); 433 if (error != NULL) 434 *error = errorc; 435 g_destroy_bio(bp); 436 if (errorc) { 437 g_free(ptr); 438 ptr = NULL; 439 } 440 return (ptr); 441} 442 443int 444g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 445{ 446 struct bio *bp; 447 int error; 448 449 KASSERT(length >= 512 && length <= DFLTPHYS, 450 ("g_write_data(): invalid length %jd", (intmax_t)length)); 451 452 bp = g_new_bio(); 453 bp->bio_cmd = BIO_WRITE; 454 bp->bio_done = NULL; 455 bp->bio_offset = offset; 456 bp->bio_length = length; 457 bp->bio_data = ptr; 458 g_io_request(bp, cp); 459 error = biowait(bp, "gwrite"); 460 g_destroy_bio(bp); 461 return (error); 462} 463 464void 465g_print_bio(struct bio *bp) 466{ 467 const char *pname, *cmd = NULL; 468 469 if (bp->bio_to != NULL) 470 pname = bp->bio_to->name; 471 else 472 pname = "[unknown]"; 473 474 switch (bp->bio_cmd) { 475 case BIO_GETATTR: 476 cmd = "GETATTR"; 477 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); 478 return; 479 case BIO_READ: 480 cmd = "READ"; 481 case BIO_WRITE: 482 if (cmd == NULL) 483 cmd = "WRITE"; 484 case BIO_DELETE: 485 if (cmd == NULL) 486 cmd = "DELETE"; 487 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, 488 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 489 return; 490 default: 491 cmd = "UNKNOWN"; 492 printf("%s[%s()]", pname, cmd); 493 return; 494 } 495 /* NOTREACHED */ 496} 497