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 55 static u_int pace; 56 static uma_zone_t biozone; 57 58 #include <machine/atomic.h> 59 60 static void 61 g_bioq_lock(struct g_bioq *bq) 62 { 63 64 mtx_lock(&bq->bio_queue_lock); 65 } 66 67 static void 68 g_bioq_unlock(struct g_bioq *bq) 69 { 70 71 mtx_unlock(&bq->bio_queue_lock); 72 } 73 74 #if 0 75 static void 76 g_bioq_destroy(struct g_bioq *bq) 77 { 78 79 mtx_destroy(&bq->bio_queue_lock); 80 } 81 #endif 82 83 static void 84 g_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 91 static struct bio * 92 g_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 } 103 104 static void 105 g_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 } 113 114 struct bio * 115 g_new_bio(void) 116 { 117 struct bio *bp; 118 119 bp = uma_zalloc(biozone, M_NOWAIT | M_ZERO); 120 return (bp); 121 } 122 123 void 124 g_destroy_bio(struct bio *bp) 125 { 126 127 uma_zfree(biozone, bp); 128 } 129 130 struct bio * 131 g_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 } 147 148 void 149 g_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 } 159 160 int 161 g_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 } 179 180 static int 181 g_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 /* Zero sectorsize is a probably lack of media */ 213 if (pp->sectorsize == 0) 214 return (ENXIO); 215 /* Reject I/O not on sector boundary */ 216 if (bp->bio_offset % pp->sectorsize) 217 return (EINVAL); 218 /* Reject I/O not integral sector long */ 219 if (bp->bio_length % pp->sectorsize) 220 return (EINVAL); 221 /* Reject requests before or past the end of media. */ 222 if (bp->bio_offset < 0) 223 return (EIO); 224 if (bp->bio_offset > pp->mediasize) 225 return (EIO); 226 break; 227 default: 228 break; 229 } 230 return (0); 231 } 232 233 void 234 g_io_request(struct bio *bp, struct g_consumer *cp) 235 { 236 struct g_provider *pp; 237 238 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 239 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 240 KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request")); 241 pp = cp->provider; 242 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 243 244 bp->bio_from = cp; 245 bp->bio_to = pp; 246 bp->bio_error = 0; 247 bp->bio_completed = 0; 248 249 if (g_collectstats) { 250 devstat_start_transaction_bio(cp->stat, bp); 251 devstat_start_transaction_bio(pp->stat, bp); 252 } 253 cp->nstart++; 254 pp->nstart++; 255 256 /* Pass it on down. */ 257 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 258 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 259 g_bioq_enqueue_tail(bp, &g_bio_run_down); 260 wakeup(&g_wait_down); 261 } 262 263 void 264 g_io_deliver(struct bio *bp, int error) 265 { 266 struct g_consumer *cp; 267 struct g_provider *pp; 268 269 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 270 pp = bp->bio_to; 271 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 272 cp = bp->bio_from; 273 if (cp == NULL) { 274 bp->bio_error = error; 275 bp->bio_done(bp); 276 return; 277 } 278 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 279 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 280 281 g_trace(G_T_BIO, 282 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 283 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 284 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 285 286 bp->bio_bcount = bp->bio_length; 287 if (g_collectstats) { 288 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 289 devstat_end_transaction_bio(cp->stat, bp); 290 devstat_end_transaction_bio(pp->stat, bp); 291 } 292 cp->nend++; 293 pp->nend++; 294 295 if (error == ENOMEM) { 296 if (bootverbose) 297 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 298 g_io_request(bp, cp); 299 pace++; 300 return; 301 } 302 bp->bio_error = error; 303 g_bioq_enqueue_tail(bp, &g_bio_run_up); 304 wakeup(&g_wait_up); 305 } 306 307 void 308 g_io_schedule_down(struct thread *tp __unused) 309 { 310 struct bio *bp; 311 off_t excess; 312 int error; 313 struct mtx mymutex; 314 315 bzero(&mymutex, sizeof mymutex); 316 mtx_init(&mymutex, "g_xdown", NULL, MTX_DEF); 317 318 for(;;) { 319 g_bioq_lock(&g_bio_run_down); 320 bp = g_bioq_first(&g_bio_run_down); 321 if (bp == NULL) { 322 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 323 PRIBIO | PDROP, "-", hz/10); 324 continue; 325 } 326 g_bioq_unlock(&g_bio_run_down); 327 if (pace > 0) { 328 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 329 pace--; 330 } 331 error = g_io_check(bp); 332 if (error) { 333 g_io_deliver(bp, error); 334 continue; 335 } 336 switch (bp->bio_cmd) { 337 case BIO_READ: 338 case BIO_WRITE: 339 case BIO_DELETE: 340 /* Truncate requests to the end of providers media. */ 341 excess = bp->bio_offset + bp->bio_length; 342 if (excess > bp->bio_to->mediasize) { 343 excess -= bp->bio_to->mediasize; 344 bp->bio_length -= excess; 345 } 346 /* Deliver zero length transfers right here. */ 347 if (bp->bio_length == 0) { 348 g_io_deliver(bp, 0); 349 continue; 350 } 351 break; 352 default: 353 break; 354 } 355 mtx_lock(&mymutex); 356 bp->bio_to->geom->start(bp); 357 mtx_unlock(&mymutex); 358 } 359 } 360 361 void 362 g_io_schedule_up(struct thread *tp __unused) 363 { 364 struct bio *bp; 365 struct mtx mymutex; 366 367 bzero(&mymutex, sizeof mymutex); 368 mtx_init(&mymutex, "g_xup", NULL, MTX_DEF); 369 for(;;) { 370 g_bioq_lock(&g_bio_run_up); 371 bp = g_bioq_first(&g_bio_run_up); 372 if (bp != NULL) { 373 g_bioq_unlock(&g_bio_run_up); 374 mtx_lock(&mymutex); 375 biodone(bp); 376 mtx_unlock(&mymutex); 377 continue; 378 } 379 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 380 PRIBIO | PDROP, "-", hz/10); 381 } 382 } 383 384 void * 385 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 386 { 387 struct bio *bp; 388 void *ptr; 389 int errorc; 390 391 KASSERT(length >= 512 && length <= DFLTPHYS, 392 ("g_read_data(): invalid length %jd", (intmax_t)length)); 393 394 bp = g_new_bio(); 395 bp->bio_cmd = BIO_READ; 396 bp->bio_done = NULL; 397 bp->bio_offset = offset; 398 bp->bio_length = length; 399 ptr = g_malloc(length, M_WAITOK); 400 bp->bio_data = ptr; 401 g_io_request(bp, cp); 402 errorc = biowait(bp, "gread"); 403 if (error != NULL) 404 *error = errorc; 405 g_destroy_bio(bp); 406 if (errorc) { 407 g_free(ptr); 408 ptr = NULL; 409 } 410 return (ptr); 411 } 412 413 int 414 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 415 { 416 struct bio *bp; 417 int error; 418 419 KASSERT(length >= 512 && length <= DFLTPHYS, 420 ("g_write_data(): invalid length %jd", (intmax_t)length)); 421 422 bp = g_new_bio(); 423 bp->bio_cmd = BIO_WRITE; 424 bp->bio_done = NULL; 425 bp->bio_offset = offset; 426 bp->bio_length = length; 427 bp->bio_data = ptr; 428 g_io_request(bp, cp); 429 error = biowait(bp, "gwrite"); 430 g_destroy_bio(bp); 431 return (error); 432 } 433