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 /* 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 past the end of media. */ 225 if (bp->bio_offset > pp->mediasize) 226 return (EIO); 227 break; 228 default: 229 break; 230 } 231 return (0); 232 } 233 234 void 235 g_io_request(struct bio *bp, struct g_consumer *cp) 236 { 237 struct g_provider *pp; 238 239 KASSERT(cp != NULL, ("NULL cp in g_io_request")); 240 KASSERT(bp != NULL, ("NULL bp in g_io_request")); 241 KASSERT(bp->bio_data != NULL, ("NULL bp->data in g_io_request")); 242 pp = cp->provider; 243 KASSERT(pp != NULL, ("consumer not attached in g_io_request")); 244 245 bp->bio_from = cp; 246 bp->bio_to = pp; 247 bp->bio_error = 0; 248 bp->bio_completed = 0; 249 250 if (g_collectstats) { 251 devstat_start_transaction_bio(cp->stat, bp); 252 devstat_start_transaction_bio(pp->stat, bp); 253 } 254 cp->nstart++; 255 pp->nstart++; 256 257 /* Pass it on down. */ 258 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 259 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd); 260 g_bioq_enqueue_tail(bp, &g_bio_run_down); 261 wakeup(&g_wait_down); 262 } 263 264 void 265 g_io_deliver(struct bio *bp, int error) 266 { 267 struct g_consumer *cp; 268 struct g_provider *pp; 269 270 KASSERT(bp != NULL, ("NULL bp in g_io_deliver")); 271 cp = bp->bio_from; 272 pp = bp->bio_to; 273 KASSERT(cp != NULL, ("NULL bio_from in g_io_deliver")); 274 KASSERT(cp->geom != NULL, ("NULL bio_from->geom in g_io_deliver")); 275 KASSERT(pp != NULL, ("NULL bio_to in g_io_deliver")); 276 277 g_trace(G_T_BIO, 278 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d off %jd len %jd", 279 bp, cp, cp->geom->name, pp, pp->name, bp->bio_cmd, error, 280 (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length); 281 282 bp->bio_bcount = bp->bio_length; 283 if (g_collectstats) { 284 bp->bio_resid = bp->bio_bcount - bp->bio_completed; 285 devstat_end_transaction_bio(cp->stat, bp); 286 devstat_end_transaction_bio(pp->stat, bp); 287 } 288 cp->nend++; 289 pp->nend++; 290 291 if (error == ENOMEM) { 292 if (bootverbose) 293 printf("ENOMEM %p on %p(%s)\n", bp, pp, pp->name); 294 g_io_request(bp, cp); 295 pace++; 296 return; 297 } 298 bp->bio_error = error; 299 g_bioq_enqueue_tail(bp, &g_bio_run_up); 300 wakeup(&g_wait_up); 301 } 302 303 void 304 g_io_schedule_down(struct thread *tp __unused) 305 { 306 struct bio *bp; 307 off_t excess; 308 int error; 309 struct mtx mymutex; 310 311 bzero(&mymutex, sizeof mymutex); 312 mtx_init(&mymutex, "g_xdown", MTX_DEF, 0); 313 314 for(;;) { 315 g_bioq_lock(&g_bio_run_down); 316 bp = g_bioq_first(&g_bio_run_down); 317 if (bp == NULL) { 318 msleep(&g_wait_down, &g_bio_run_down.bio_queue_lock, 319 PRIBIO | PDROP, "-", hz/10); 320 continue; 321 } 322 g_bioq_unlock(&g_bio_run_down); 323 if (pace > 0) { 324 msleep(&error, NULL, PRIBIO, "g_down", hz/10); 325 pace--; 326 } 327 error = g_io_check(bp); 328 if (error) { 329 g_io_deliver(bp, error); 330 continue; 331 } 332 switch (bp->bio_cmd) { 333 case BIO_READ: 334 case BIO_WRITE: 335 case BIO_DELETE: 336 /* Truncate requests to the end of providers media. */ 337 excess = bp->bio_offset + bp->bio_length; 338 if (excess > bp->bio_to->mediasize) { 339 excess -= bp->bio_to->mediasize; 340 bp->bio_length -= excess; 341 } 342 /* Deliver zero length transfers right here. */ 343 if (bp->bio_length == 0) { 344 g_io_deliver(bp, 0); 345 continue; 346 } 347 break; 348 default: 349 break; 350 } 351 mtx_lock(&mymutex); 352 bp->bio_to->geom->start(bp); 353 mtx_unlock(&mymutex); 354 } 355 } 356 357 void 358 g_io_schedule_up(struct thread *tp __unused) 359 { 360 struct bio *bp; 361 struct mtx mymutex; 362 363 bzero(&mymutex, sizeof mymutex); 364 mtx_init(&mymutex, "g_xup", MTX_DEF, 0); 365 for(;;) { 366 g_bioq_lock(&g_bio_run_up); 367 bp = g_bioq_first(&g_bio_run_up); 368 if (bp != NULL) { 369 g_bioq_unlock(&g_bio_run_up); 370 mtx_lock(&mymutex); 371 biodone(bp); 372 mtx_unlock(&mymutex); 373 continue; 374 } 375 msleep(&g_wait_up, &g_bio_run_up.bio_queue_lock, 376 PRIBIO | PDROP, "-", hz/10); 377 } 378 } 379 380 void * 381 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 382 { 383 struct bio *bp; 384 void *ptr; 385 int errorc; 386 387 bp = g_new_bio(); 388 bp->bio_cmd = BIO_READ; 389 bp->bio_done = NULL; 390 bp->bio_offset = offset; 391 bp->bio_length = length; 392 ptr = g_malloc(length, M_WAITOK); 393 bp->bio_data = ptr; 394 g_io_request(bp, cp); 395 errorc = biowait(bp, "gread"); 396 if (error != NULL) 397 *error = errorc; 398 g_destroy_bio(bp); 399 if (errorc) { 400 g_free(ptr); 401 ptr = NULL; 402 } 403 return (ptr); 404 } 405 406 int 407 g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length) 408 { 409 struct bio *bp; 410 int error; 411 412 bp = g_new_bio(); 413 bp->bio_cmd = BIO_WRITE; 414 bp->bio_done = NULL; 415 bp->bio_offset = offset; 416 bp->bio_length = length; 417 bp->bio_data = ptr; 418 g_io_request(bp, cp); 419 error = biowait(bp, "gwrite"); 420 g_destroy_bio(bp); 421 return (error); 422 } 423