geom_io.c revision 121253
1118856Sphk/*- 2118856Sphk * Copyright (c) 2002 Poul-Henning Kamp 3118856Sphk * Copyright (c) 2002 Networks Associates Technology, Inc. 4118856Sphk * All rights reserved. 5118856Sphk * 6118856Sphk * 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 121253 2003-10-19 19:06:54Z 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; 54 55static u_int pace; 56static uma_zone_t biozone; 57 58#include <machine/atomic.h> 59 60static void 61g_bioq_lock(struct g_bioq *bq) 62{ 63 64 mtx_lock(&bq->bio_queue_lock); 65} 66 67static void 68g_bioq_unlock(struct g_bioq *bq) 69{ 70 71 mtx_unlock(&bq->bio_queue_lock); 72} 73 74#if 0 75static void 76g_bioq_destroy(struct g_bioq *bq) 77{ 78 79 mtx_destroy(&bq->bio_queue_lock); 80} 81#endif 82 83static void 84g_bioq_init(struct g_bioq *bq) 85{ 86 87 TAILQ_INIT(&bq->bio_queue); 88 mtx_init(&bq->bio_queue_lock, "bio queue", NULL, MTX_DEF); 89} 90 91static struct bio * 92g_bioq_first(struct g_bioq *bq) 93{ 94 struct bio *bp; 95 96 bp = TAILQ_FIRST(&bq->bio_queue); 97 if (bp != NULL) { 98 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 99 bq->bio_queue_length--; 100 } 101 return (bp); 102} 103 104static void 105g_bioq_enqueue_tail(struct bio *bp, struct g_bioq *rq) 106{ 107 108 g_bioq_lock(rq); 109 TAILQ_INSERT_TAIL(&rq->bio_queue, bp, bio_queue); 110 rq->bio_queue_length++; 111 g_bioq_unlock(rq); 112} 113 114struct bio * 115g_new_bio(void) 116{ 117 struct bio *bp; 118 119 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 120 return (bp); 121} 122 123void 124g_destroy_bio(struct bio *bp) 125{ 126 127 uma_zfree(biozone, bp); 128} 129 130struct bio * 131g_clone_bio(struct bio *bp) 132{ 133 struct bio *bp2; 134 135 bp2 = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 136 if (bp2 != NULL) { 137 bp2->bio_parent = bp; 138 bp2->bio_cmd = bp->bio_cmd; 139 bp2->bio_length = bp->bio_length; 140 bp2->bio_offset = bp->bio_offset; 141 bp2->bio_data = bp->bio_data; 142 bp2->bio_attribute = bp->bio_attribute; 143 bp->bio_children++; 144 } 145 return(bp2); 146} 147 148void 149g_io_init() 150{ 151 152 g_bioq_init(&g_bio_run_down); 153 g_bioq_init(&g_bio_run_up); 154 biozone = uma_zcreate("g_bio", sizeof (struct bio), 155 NULL, NULL, 156 NULL, NULL, 157 0, 0); 158} 159 160int 161g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr) 162{ 163 struct bio *bp; 164 int error; 165 166 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 167 bp = g_new_bio(); 168 bp->bio_cmd = BIO_GETATTR; 169 bp->bio_done = NULL; 170 bp->bio_attribute = attr; 171 bp->bio_length = *len; 172 bp->bio_data = ptr; 173 g_io_request(bp, cp); 174 error = biowait(bp, "ggetattr"); 175 *len = bp->bio_completed; 176 g_destroy_bio(bp); 177 return (error); 178} 179 180static int 181g_io_check(struct bio *bp) 182{ 183 struct g_consumer *cp; 184 struct g_provider *pp; 185 186 cp = bp->bio_from; 187 pp = bp->bio_to; 188 189 /* Fail if access counters dont allow the operation */ 190 switch(bp->bio_cmd) { 191 case BIO_READ: 192 case BIO_GETATTR: 193 if (cp->acr == 0) 194 return (EPERM); 195 break; 196 case BIO_WRITE: 197 case BIO_DELETE: 198 if (cp->acw == 0) 199 return (EPERM); 200 break; 201 default: 202 return (EPERM); 203 } 204 /* if provider is marked for error, don't disturb. */ 205 if (pp->error) 206 return (pp->error); 207 208 switch(bp->bio_cmd) { 209 case BIO_READ: 210 case BIO_WRITE: 211 case BIO_DELETE: 212 /* Noisily reject zero size sectors */ 213 if (pp->sectorsize == 0) { 214 printf("GEOM provider %s has zero sectorsize\n", 215 pp->name); 216 return (EDOOFUS); 217 } 218 /* Reject I/O not on sector boundary */ 219 if (bp->bio_offset % pp->sectorsize) 220 return (EINVAL); 221 /* Reject I/O not integral sector long */ 222 if (bp->bio_length % pp->sectorsize) 223 return (EINVAL); 224 /* Reject requests before or past the end of media. */ 225 if (bp->bio_offset < 0) 226 return (EIO); 227 if (bp->bio_offset > pp->mediasize) 228 return (EIO); 229 break; 230 default: 231 break; 232 } 233 return (0); 234} 235 236void 237g_io_request(struct bio *bp, struct g_consumer *cp) 238{ 239 struct g_provider *pp; 240 241 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 242 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 243 KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request")); 244 pp = cp->provider; 245 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 246 247 bp->bio_from = cp; 248 bp->bio_to = pp; 249 bp->bio_error = 0; 250 bp->bio_completed = 0; 251 252 if (g_collectstats) { 253 devstat_start_transaction_bio(cp->stat, bp); 254 devstat_start_transaction_bio(pp->stat, bp); 255 } 256 cp->nstart++; 257 pp->nstart++; 258 259 /* Pass it on down. */ 260 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 261 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 262 g_bioq_enqueue_tail(bp, &g_bio_run_down); 263 wakeup(&g_wait_down); 264} 265 266void 267g_io_deliver(struct bio *bp, int error) 268{ 269 struct g_consumer *cp; 270 struct g_provider *pp; 271 272 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 273 pp = bp->bio_to; 274 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 275 cp = bp->bio_from; 276 if (cp == NULL) { 277 bp->bio_error = error; 278 bp->bio_done(bp); 279 return; 280 } 281 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 282 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 283 284 g_trace(G_T_BIO, 285"g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 286 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 287 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 288 289 bp->bio_bcount = bp->bio_length; 290 if (g_collectstats) { 291 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 292 devstat_end_transaction_bio(cp->stat, bp); 293 devstat_end_transaction_bio(pp->stat, bp); 294 } 295 cp->nend++; 296 pp->nend++; 297 298 if (error == ENOMEM) { 299 if (bootverbose) 300 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 301 g_io_request(bp, cp); 302 pace++; 303 return; 304 } 305 bp->bio_error = error; 306 g_bioq_enqueue_tail(bp, &g_bio_run_up); 307 wakeup(&g_wait_up); 308} 309 310void 311g_io_schedule_down(struct thread *tp __unused) 312{ 313 struct bio *bp; 314 off_t excess; 315 int error; 316 struct mtx mymutex; 317 318 bzero(&mymutex, sizeof mymutex); 319 mtx_init(&mymutex, "g_xdown", MTX_DEF, 0); 320 321 for(;;) { 322 g_bioq_lock(&g_bio_run_down); 323 bp = g_bioq_first(&g_bio_run_down); 324 if (bp == NULL) { 325 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 326 PRIBIO | PDROP, "-", hz/10); 327 continue; 328 } 329 g_bioq_unlock(&g_bio_run_down); 330 if (pace > 0) { 331 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 332 pace--; 333 } 334 error = g_io_check(bp); 335 if (error) { 336 g_io_deliver(bp, error); 337 continue; 338 } 339 switch (bp->bio_cmd) { 340 case BIO_READ: 341 case BIO_WRITE: 342 case BIO_DELETE: 343 /* Truncate requests to the end of providers media. */ 344 excess = bp->bio_offset + bp->bio_length; 345 if (excess > bp->bio_to->mediasize) { 346 excess -= bp->bio_to->mediasize; 347 bp->bio_length -= excess; 348 } 349 /* Deliver zero length transfers right here. */ 350 if (bp->bio_length == 0) { 351 g_io_deliver(bp, 0); 352 continue; 353 } 354 break; 355 default: 356 break; 357 } 358 mtx_lock(&mymutex); 359 bp->bio_to->geom->start(bp); 360 mtx_unlock(&mymutex); 361 } 362} 363 364void 365g_io_schedule_up(struct thread *tp __unused) 366{ 367 struct bio *bp; 368 struct mtx mymutex; 369 370 bzero(&mymutex, sizeof mymutex); 371 mtx_init(&mymutex, "g_xup", MTX_DEF, 0); 372 for(;;) { 373 g_bioq_lock(&g_bio_run_up); 374 bp = g_bioq_first(&g_bio_run_up); 375 if (bp != NULL) { 376 g_bioq_unlock(&g_bio_run_up); 377 mtx_lock(&mymutex); 378 biodone(bp); 379 mtx_unlock(&mymutex); 380 continue; 381 } 382 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 383 PRIBIO | PDROP, "-", hz/10); 384 } 385} 386 387void * 388g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 389{ 390 struct bio *bp; 391 void *ptr; 392 int errorc; 393 394 KASSERT(length >= 512 && length <= DFLTPHYS, 395 ("g_read_data(): invalid length %jd", (intmax_t)length)); 396 397 bp = g_new_bio(); 398 bp->bio_cmd = BIO_READ; 399 bp->bio_done = NULL; 400 bp->bio_offset = offset; 401 bp->bio_length = length; 402 ptr = g_malloc(length, M_WAITOK); 403 bp->bio_data = ptr; 404 g_io_request(bp, cp); 405 errorc = biowait(bp, "gread"); 406 if (error != NULL) 407 *error = errorc; 408 g_destroy_bio(bp); 409 if (errorc) { 410 g_free(ptr); 411 ptr = NULL; 412 } 413 return (ptr); 414} 415 416int 417g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 418{ 419 struct bio *bp; 420 int error; 421 422 KASSERT(length >= 512 && length <= DFLTPHYS, 423 ("g_write_data(): invalid length %jd", (intmax_t)length)); 424 425 bp = g_new_bio(); 426 bp->bio_cmd = BIO_WRITE; 427 bp->bio_done = NULL; 428 bp->bio_offset = offset; 429 bp->bio_length = length; 430 bp->bio_data = ptr; 431 g_io_request(bp, cp); 432 error = biowait(bp, "gwrite"); 433 g_destroy_bio(bp); 434 return (error); 435} 436