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 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 100 bq->bio_queue_length--; 101 } 102 return (bp); 103 } 104 105 static void 106 g_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 } 114 115 struct bio * 116 g_new_bio(void) 117 { 118 struct bio *bp; 119 120 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 121 return (bp); 122 } 123 124 void 125 g_destroy_bio(struct bio *bp) 126 { 127 128 uma_zfree(biozone, bp); 129 } 130 131 struct bio * 132 g_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 } 148 149 void 150 g_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 } 161 162 int 163 g_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 } 181 182 static int 183 g_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 } 234 235 void 236 g_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) { 252 devstat_start_transaction_bio(cp->stat, bp); 253 devstat_start_transaction_bio(pp->stat, bp); 254 } 255 cp->nstart++; 256 pp->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 } 264 265 void 266 g_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")); 282 283 g_trace(G_T_BIO, 284 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 285 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 286 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 287 288 bp->bio_bcount = bp->bio_length; 289 if (g_collectstats) { 290 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 291 devstat_end_transaction_bio(cp->stat, bp); 292 devstat_end_transaction_bio(pp->stat, bp); 293 } 294 cp->nend++; 295 pp->nend++; 296 297 if (error == ENOMEM) { 298 if (bootverbose) 299 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 300 g_io_request(bp, cp); 301 pace++; 302 return; 303 } 304 bp->bio_error = error; 305 g_bioq_enqueue_tail(bp, &g_bio_run_up); 306 wakeup(&g_wait_up); 307 } 308 309 void 310 g_io_schedule_down(struct thread *tp __unused) 311 { 312 struct bio *bp; 313 off_t excess; 314 int error; 315 struct mtx mymutex; 316 317 bzero(&mymutex, sizeof mymutex); 318 mtx_init(&mymutex, "g_xdown", NULL, MTX_DEF); 319 320 for(;;) { 321 g_bioq_lock(&g_bio_run_down); 322 bp = g_bioq_first(&g_bio_run_down); 323 if (bp == NULL) { 324 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 325 PRIBIO | PDROP, "-", hz/10); 326 continue; 327 } 328 g_bioq_unlock(&g_bio_run_down); 329 if (pace > 0) { 330 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 331 pace--; 332 } 333 error = g_io_check(bp); 334 if (error) { 335 g_io_deliver(bp, error); 336 continue; 337 } 338 switch (bp->bio_cmd) { 339 case BIO_READ: 340 case BIO_WRITE: 341 case BIO_DELETE: 342 /* Truncate requests to the end of providers media. */ 343 excess = bp->bio_offset + bp->bio_length; 344 if (excess > bp->bio_to->mediasize) { 345 excess -= bp->bio_to->mediasize; 346 bp->bio_length -= excess; 347 } 348 /* Deliver zero length transfers right here. */ 349 if (bp->bio_length == 0) { 350 g_io_deliver(bp, 0); 351 continue; 352 } 353 break; 354 default: 355 break; 356 } 357 mtx_lock(&mymutex); 358 bp->bio_to->geom->start(bp); 359 mtx_unlock(&mymutex); 360 } 361 } 362 363 void 364 bio_taskqueue(struct bio *bp, bio_task_t *func, void *arg) 365 { 366 bp->bio_task = func; 367 bp->bio_task_arg = arg; 368 /* 369 * The taskqueue is actually just a second queue off the "up" 370 * queue, so we use the same lock. 371 */ 372 g_bioq_lock(&g_bio_run_up); 373 TAILQ_INSERT_TAIL(&g_bio_run_task.bio_queue, bp, bio_queue); 374 g_bio_run_task.bio_queue_length++; 375 wakeup(&g_wait_up); 376 g_bioq_unlock(&g_bio_run_up); 377 } 378 379 380 void 381 g_io_schedule_up(struct thread *tp __unused) 382 { 383 struct bio *bp; 384 struct mtx mymutex; 385 386 bzero(&mymutex, sizeof mymutex); 387 mtx_init(&mymutex, "g_xup", NULL, MTX_DEF); 388 for(;;) { 389 g_bioq_lock(&g_bio_run_up); 390 bp = g_bioq_first(&g_bio_run_task); 391 if (bp != NULL) { 392 g_bioq_unlock(&g_bio_run_up); 393 mtx_lock(&mymutex); 394 bp->bio_task(bp->bio_task_arg); 395 mtx_unlock(&mymutex); 396 continue; 397 } 398 bp = g_bioq_first(&g_bio_run_up); 399 if (bp != NULL) { 400 g_bioq_unlock(&g_bio_run_up); 401 mtx_lock(&mymutex); 402 biodone(bp); 403 mtx_unlock(&mymutex); 404 continue; 405 } 406 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 407 PRIBIO | PDROP, "-", hz/10); 408 } 409 } 410 411 void * 412 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 413 { 414 struct bio *bp; 415 void *ptr; 416 int errorc; 417 418 KASSERT(length >= 512 && length <= DFLTPHYS, 419 ("g_read_data(): invalid length %jd", (intmax_t)length)); 420 421 bp = g_new_bio(); 422 bp->bio_cmd = BIO_READ; 423 bp->bio_done = NULL; 424 bp->bio_offset = offset; 425 bp->bio_length = length; 426 ptr = g_malloc(length, M_WAITOK); 427 bp->bio_data = ptr; 428 g_io_request(bp, cp); 429 errorc = biowait(bp, "gread"); 430 if (error != NULL) 431 *error = errorc; 432 g_destroy_bio(bp); 433 if (errorc) { 434 g_free(ptr); 435 ptr = NULL; 436 } 437 return (ptr); 438 } 439 440 int 441 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 442 { 443 struct bio *bp; 444 int error; 445 446 KASSERT(length >= 512 && length <= DFLTPHYS, 447 ("g_write_data(): invalid length %jd", (intmax_t)length)); 448 449 bp = g_new_bio(); 450 bp->bio_cmd = BIO_WRITE; 451 bp->bio_done = NULL; 452 bp->bio_offset = offset; 453 bp->bio_length = length; 454 bp->bio_data = ptr; 455 g_io_request(bp, cp); 456 error = biowait(bp, "gwrite"); 457 g_destroy_bio(bp); 458 return (error); 459 } 460 461 void 462 g_print_bio(struct bio *bp) 463 { 464 const char *pname, *cmd = NULL; 465 466 if (bp->bio_to != NULL) 467 pname = bp->bio_to->name; 468 else 469 pname = "[unknown]"; 470 471 switch (bp->bio_cmd) { 472 case BIO_GETATTR: 473 cmd = "GETATTR"; 474 printf("%s[%s(attr=%s)]", pname, cmd, bp->bio_attribute); 475 return; 476 case BIO_READ: 477 cmd = "READ"; 478 case BIO_WRITE: 479 if (cmd == NULL) 480 cmd = "WRITE"; 481 case BIO_DELETE: 482 if (cmd == NULL) 483 cmd = "DELETE"; 484 printf("%s[%s(offset=%jd, length=%jd)]", pname, cmd, 485 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 486 return; 487 default: 488 cmd = "UNKNOWN"; 489 printf("%s[%s()]", pname, cmd); 490 return; 491 } 492 /* NOTREACHED */ 493 } 494