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("$FreeBSD$"); 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 52 static struct g_bioq g_bio_run_down; 53 static struct g_bioq g_bio_run_up; 54 static struct g_bioq g_bio_run_task; 55 56 static u_int pace; 57 static uma_zone_t biozone; 58 59 #include <machine/atomic.h> 60 61 static void 62 g_bioq_lock(struct g_bioq *bq) 63 { 64 65 mtx_lock(&bq->bio_queue_lock); 66 } 67 68 static void 69 g_bioq_unlock(struct g_bioq *bq) 70 { 71 72 mtx_unlock(&bq->bio_queue_lock); 73 } 74 75 #if 0 76 static void 77 g_bioq_destroy(struct g_bioq *bq) 78 { 79 80 mtx_destroy(&bq->bio_queue_lock); 81 } 82 #endif 83 84 static void 85 g_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 92 static struct bio * 93 g_bioq_first(struct g_bioq *bq) 94 { 95 struct bio *bp; 96 97 bp = TAILQ_FIRST(&bq->bio_queue); 98 if (bp != NULL) { 99 KASSERT((bp->bio_flags & BIO_ONQUEUE), 100 ("Bio not on queue bp=%p target %p", bp, bq)); 101 bp->bio_flags &= ~BIO_ONQUEUE; 102 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 103 bq->bio_queue_length--; 104 } 105 return (bp); 106 } 107 108 static void 109 g_bioq_enqueue_tail(struct bio *bp, struct g_bioq *rq) 110 { 111 112 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 113 ("Bio already on queue bp=%p target %p", bp, rq)); 114 bp->bio_flags |= BIO_ONQUEUE; 115 g_bioq_lock(rq); 116 TAILQ_INSERT_TAIL(&rq->bio_queue, bp, bio_queue); 117 rq->bio_queue_length++; 118 g_bioq_unlock(rq); 119 } 120 121 struct bio * 122 g_new_bio(void) 123 { 124 struct bio *bp; 125 126 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 127 return (bp); 128 } 129 130 struct bio * 131 g_alloc_bio(void) 132 { 133 struct bio *bp; 134 135 bp = uma_zalloc(biozone, M_WAITOK | M_ZERO); 136 return (bp); 137 } 138 139 void 140 g_destroy_bio(struct bio *bp) 141 { 142 143 uma_zfree(biozone, bp); 144 } 145 146 struct bio * 147 g_clone_bio(struct bio *bp) 148 { 149 struct bio *bp2; 150 151 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 152 if (bp2 != NULL) { 153 bp2->bio_parent = bp; 154 bp2->bio_cmd = bp->bio_cmd; 155 bp2->bio_length = bp->bio_length; 156 bp2->bio_offset = bp->bio_offset; 157 bp2->bio_data = bp->bio_data; 158 bp2->bio_attribute = bp->bio_attribute; 159 bp->bio_children++; 160 } 161 return(bp2); 162 } 163 164 void 165 g_io_init() 166 { 167 168 g_bioq_init(&g_bio_run_down); 169 g_bioq_init(&g_bio_run_up); 170 g_bioq_init(&g_bio_run_task); 171 biozone = uma_zcreate("g_bio", sizeof (struct bio), 172 NULL, NULL, 173 NULL, NULL, 174 0, 0); 175 } 176 177 int 178 g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 179 { 180 struct bio *bp; 181 int error; 182 183 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 184 bp = g_alloc_bio(); 185 bp->bio_cmd = BIO_GETATTR; 186 bp->bio_done = NULL; 187 bp->bio_attribute = attr; 188 bp->bio_length = *len; 189 bp->bio_data = ptr; 190 g_io_request(bp, cp); 191 error = biowait(bp, "ggetattr"); 192 *len = bp->bio_completed; 193 g_destroy_bio(bp); 194 return (error); 195 } 196 197 static int 198 g_io_check(struct bio *bp) 199 { 200 struct g_consumer *cp; 201 struct g_provider *pp; 202 203 cp = bp->bio_from; 204 pp = bp->bio_to; 205 206 /* Fail if access counters dont allow the operation */ 207 switch(bp->bio_cmd) { 208 case BIO_READ: 209 case BIO_GETATTR: 210 if (cp->acr == 0) 211 return (EPERM); 212 break; 213 case BIO_WRITE: 214 case BIO_DELETE: 215 if (cp->acw == 0) 216 return (EPERM); 217 break; 218 default: 219 return (EPERM); 220 } 221 /* if provider is marked for error, don't disturb. */ 222 if (pp->error) 223 return (pp->error); 224 225 switch(bp->bio_cmd) { 226 case BIO_READ: 227 case BIO_WRITE: 228 case BIO_DELETE: 229 /* Zero sectorsize is a probably lack of media */ 230 if (pp->sectorsize == 0) 231 return (ENXIO); 232 /* Reject I/O not on sector boundary */ 233 if (bp->bio_offset % pp->sectorsize) 234 return (EINVAL); 235 /* Reject I/O not integral sector long */ 236 if (bp->bio_length % pp->sectorsize) 237 return (EINVAL); 238 /* Reject requests before or past the end of media. */ 239 if (bp->bio_offset < 0) 240 return (EIO); 241 if (bp->bio_offset > pp->mediasize) 242 return (EIO); 243 break; 244 default: 245 break; 246 } 247 return (0); 248 } 249 250 void 251 g_io_request(struct bio *bp, struct g_consumer *cp) 252 { 253 struct g_provider *pp; 254 255 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 256 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 257 KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request")); 258 pp = cp->provider; 259 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 260 261 if (bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) { 262 KASSERT(bp->bio_offset % cp->provider->sectorsize == 0, 263 ("wrong offset %jd for sectorsize %u", 264 bp->bio_offset, cp->provider->sectorsize)); 265 KASSERT(bp->bio_length % cp->provider->sectorsize == 0, 266 ("wrong length %jd for sectorsize %u", 267 bp->bio_length, cp->provider->sectorsize)); 268 } 269 270 bp->bio_from = cp; 271 bp->bio_to = pp; 272 bp->bio_error = 0; 273 bp->bio_completed = 0; 274 275 if (g_collectstats & 1) 276 devstat_start_transaction_bio(pp->stat, bp); 277 pp->nstart++; 278 if (g_collectstats & 2) 279 devstat_start_transaction_bio(cp->stat, bp); 280 cp->nstart++; 281 282 /* Pass it on down. */ 283 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 284 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 285 g_bioq_enqueue_tail(bp, &g_bio_run_down); 286 wakeup(&g_wait_down); 287 } 288 289 void 290 g_io_deliver(struct bio *bp, int error) 291 { 292 struct g_consumer *cp; 293 struct g_provider *pp; 294 295 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 296 pp = bp->bio_to; 297 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 298 cp = bp->bio_from; 299 if (cp == NULL) { 300 bp->bio_error = error; 301 bp->bio_done(bp); 302 return; 303 } 304 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 305 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 306 KASSERT(bp->bio_completed >= 0, ("bio_completed can't be less than 0")); 307 KASSERT(bp->bio_completed <= bp->bio_length, 308 ("bio_completed can't be greater than bio_length")); 309 310 g_trace(G_T_BIO, 311 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 312 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 313 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 314 315 /* 316 * XXX: next two doesn't belong here 317 */ 318 bp->bio_bcount = bp->bio_length; 319 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 320 if (g_collectstats & 1) 321 devstat_end_transaction_bio(pp->stat, bp); 322 if (g_collectstats & 2) 323 devstat_end_transaction_bio(cp->stat, bp); 324 cp->nend++; 325 pp->nend++; 326 327 if (error == ENOMEM) { 328 if (bootverbose) 329 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 330 bp->bio_children = 0; 331 bp->bio_inbed = 0; 332 g_io_request(bp, cp); 333 pace++; 334 return; 335 } 336 bp->bio_error = error; 337 g_bioq_enqueue_tail(bp, &g_bio_run_up); 338 wakeup(&g_wait_up); 339 } 340 341 void 342 g_io_schedule_down(struct thread *tp __unused) 343 { 344 struct bio *bp; 345 off_t excess; 346 int error; 347 #ifdef WITNESS 348 struct mtx mymutex; 349 350 bzero(&mymutex, sizeof mymutex); 351 mtx_init(&mymutex, "g_xdown", NULL, MTX_DEF); 352 #endif 353 354 for(;;) { 355 g_bioq_lock(&g_bio_run_down); 356 bp = g_bioq_first(&g_bio_run_down); 357 if (bp == NULL) { 358 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 359 PRIBIO | PDROP, "-", hz/10); 360 continue; 361 } 362 g_bioq_unlock(&g_bio_run_down); 363 if (pace > 0) { 364 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 365 pace--; 366 } 367 error = g_io_check(bp); 368 if (error) { 369 g_io_deliver(bp, error); 370 continue; 371 } 372 switch (bp->bio_cmd) { 373 case BIO_READ: 374 case BIO_WRITE: 375 case BIO_DELETE: 376 /* Truncate requests to the end of providers media. */ 377 excess = bp->bio_offset + bp->bio_length; 378 if (excess > bp->bio_to->mediasize) { 379 excess -= bp->bio_to->mediasize; 380 bp->bio_length -= excess; 381 } 382 /* Deliver zero length transfers right here. */ 383 if (bp->bio_length == 0) { 384 g_io_deliver(bp, 0); 385 continue; 386 } 387 break; 388 default: 389 break; 390 } 391 #ifdef WITNESS 392 mtx_lock(&mymutex); 393 #endif 394 bp->bio_to->geom->start(bp); 395 #ifdef WITNESS 396 mtx_unlock(&mymutex); 397 #endif 398 } 399 } 400 401 void 402 bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg) 403 { 404 bp->bio_task = func; 405 bp->bio_task_arg = arg; 406 /* 407 * The taskqueue is actually just a second queue off the "up" 408 * queue, so we use the same lock. 409 */ 410 g_bioq_lock(&g_bio_run_up); 411 KASSERT(!(bp->bio_flags & BIO_ONQUEUE), 412 ("Bio already on queue bp=%p target taskq", bp)); 413 bp->bio_flags |= BIO_ONQUEUE; 414 TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue); 415 g_bio_run_task.bio_queue_length++; 416 wakeup(&g_wait_up); 417 g_bioq_unlock(&g_bio_run_up); 418 } 419 420 421 void 422 g_io_schedule_up(struct thread *tp __unused) 423 { 424 struct bio *bp; 425 #ifdef WITNESS 426 struct mtx mymutex; 427 428 bzero(&mymutex, sizeof mymutex); 429 mtx_init(&mymutex, "g_xup", NULL, MTX_DEF); 430 #endif 431 for(;;) { 432 g_bioq_lock(&g_bio_run_up); 433 bp = g_bioq_first(&g_bio_run_task); 434 if (bp != NULL) { 435 g_bioq_unlock(&g_bio_run_up); 436 #ifdef WITNESS 437 mtx_lock(&mymutex); 438 #endif 439 bp->bio_task(bp->bio_task_arg); 440 #ifdef WITNESS 441 mtx_unlock(&mymutex); 442 #endif 443 continue; 444 } 445 bp = g_bioq_first(&g_bio_run_up); 446 if (bp != NULL) { 447 g_bioq_unlock(&g_bio_run_up); 448 #ifdef WITNESS 449 mtx_lock(&mymutex); 450 #endif 451 biodone(bp); 452 #ifdef WITNESS 453 mtx_unlock(&mymutex); 454 #endif 455 continue; 456 } 457 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 458 PRIBIO | PDROP, "-", hz/10); 459 } 460 } 461 462 void * 463 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 464 { 465 struct bio *bp; 466 void *ptr; 467 int errorc; 468 469 KASSERT(length >= 512 && length <= DFLTPHYS, 470 ("g_read_data(): invalid length %jd", (intmax_t)length)); 471 472 bp = g_alloc_bio(); 473 bp->bio_cmd = BIO_READ; 474 bp->bio_done = NULL; 475 bp->bio_offset = offset; 476 bp->bio_length = length; 477 ptr = g_malloc(length, M_WAITOK); 478 bp->bio_data = ptr; 479 g_io_request(bp, cp); 480 errorc = biowait(bp, "gread"); 481 if (error != NULL) 482 *error = errorc; 483 g_destroy_bio(bp); 484 if (errorc) { 485 g_free(ptr); 486 ptr = NULL; 487 } 488 return (ptr); 489 } 490 491 int 492 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 493 { 494 struct bio *bp; 495 int error; 496 497 KASSERT(length >= 512 && length <= DFLTPHYS, 498 ("g_write_data(): invalid length %jd", (intmax_t)length)); 499 500 bp = g_alloc_bio(); 501 bp->bio_cmd = BIO_WRITE; 502 bp->bio_done = NULL; 503 bp->bio_offset = offset; 504 bp->bio_length = length; 505 bp->bio_data = ptr; 506 g_io_request(bp, cp); 507 error = biowait(bp, "gwrite"); 508 g_destroy_bio(bp); 509 return (error); 510 } 511 512 void 513 g_print_bio(struct bio *bp) 514 { 515 const char *pname, *cmd = NULL; 516 517 if (bp->bio_to != NULL) 518 pname = bp->bio_to->name; 519 else 520 pname = "[unknown]"; 521 522 switch (bp->bio_cmd) { 523 case BIO_GETATTR: 524 cmd = "GETATTR"; 525 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); 526 return; 527 case BIO_READ: 528 cmd = "READ"; 529 case BIO_WRITE: 530 if (cmd == NULL) 531 cmd = "WRITE"; 532 case BIO_DELETE: 533 if (cmd == NULL) 534 cmd = "DELETE"; 535 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, 536 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 537 return; 538 default: 539 cmd = "UNKNOWN"; 540 printf("%s[%s()]", pname, cmd); 541 return; 542 } 543 /* NOTREACHED */ 544 } 545