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 * $FreeBSD$ 36 */ 37 38 39 #include <sys/param.h> 40 #ifndef _KERNEL 41 #include <stdio.h> 42 #include <string.h> 43 #include <stdlib.h> 44 #include <signal.h> 45 #include <err.h> 46 #include <sched.h> 47 #else 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/malloc.h> 51 #include <sys/bio.h> 52 #endif 53 54 #include <sys/errno.h> 55 #include <geom/geom.h> 56 57 static struct g_bioq g_bio_run_down; 58 static struct g_bioq g_bio_run_up; 59 static struct g_bioq g_bio_idle; 60 61 #include <machine/atomic.h> 62 63 static void 64 g_bioq_lock(struct g_bioq *bq) 65 { 66 67 mtx_lock(&bq->bio_queue_lock); 68 } 69 70 static void 71 g_bioq_unlock(struct g_bioq *bq) 72 { 73 74 mtx_unlock(&bq->bio_queue_lock); 75 } 76 77 #if 0 78 static void 79 g_bioq_destroy(struct g_bioq *bq) 80 { 81 82 mtx_destroy(&bq->bio_queue_lock); 83 } 84 #endif 85 86 static void 87 g_bioq_init(struct g_bioq *bq) 88 { 89 90 TAILQ_INIT(&bq->bio_queue); 91 mtx_init(&bq->bio_queue_lock, "bio queue", MTX_DEF); 92 } 93 94 static struct bio * 95 g_bioq_first(struct g_bioq *bq) 96 { 97 struct bio *bp; 98 99 g_bioq_lock(bq); 100 bp = TAILQ_FIRST(&bq->bio_queue); 101 if (bp != NULL) { 102 TAILQ_REMOVE(&bq->bio_queue, bp, bio_queue); 103 bq->bio_queue_length--; 104 } 105 g_bioq_unlock(bq); 106 return (bp); 107 } 108 109 static void 110 g_bioq_enqueue_tail(struct bio *bp, struct g_bioq *rq) 111 { 112 113 g_bioq_lock(rq); 114 TAILQ_INSERT_TAIL(&rq->bio_queue, bp, bio_queue); 115 rq->bio_queue_length++; 116 g_bioq_unlock(rq); 117 } 118 119 struct bio * 120 g_new_bio(void) 121 { 122 struct bio *bp; 123 124 bp = g_bioq_first(&g_bio_idle); 125 if (bp == NULL) 126 bp = g_malloc(sizeof *bp, M_WAITOK | M_ZERO); 127 g_trace(G_T_BIO, "g_new_bio() = %p", bp); 128 return (bp); 129 } 130 131 void 132 g_destroy_bio(struct bio *bp) 133 { 134 135 g_trace(G_T_BIO, "g_destroy_bio(%p)", bp); 136 bzero(bp, sizeof *bp); 137 g_bioq_enqueue_tail(bp, &g_bio_idle); 138 } 139 140 struct bio * 141 g_clone_bio(struct bio *bp) 142 { 143 struct bio *bp2; 144 145 bp2 = g_new_bio(); 146 bp2->bio_linkage = bp; 147 bp2->bio_cmd = bp->bio_cmd; 148 bp2->bio_length = bp->bio_length; 149 bp2->bio_offset = bp->bio_offset; 150 bp2->bio_data = bp->bio_data; 151 bp2->bio_attribute = bp->bio_attribute; 152 g_trace(G_T_BIO, "g_clone_bio(%p) = %p", bp, bp2); 153 return(bp2); 154 } 155 156 void 157 g_io_init() 158 { 159 160 g_bioq_init(&g_bio_run_down); 161 g_bioq_init(&g_bio_run_up); 162 g_bioq_init(&g_bio_idle); 163 } 164 165 int 166 g_io_setattr(char *attr, struct g_consumer *cp, int len, void *ptr, struct thread *tp __unused) 167 { 168 struct bio *bp; 169 int error; 170 171 g_trace(G_T_BIO, "bio_setattr(%s)", attr); 172 do { 173 bp = g_new_bio(); 174 bp->bio_cmd = BIO_SETATTR; 175 bp->bio_done = NULL; 176 bp->bio_attribute = attr; 177 bp->bio_length = len; 178 bp->bio_data = ptr; 179 g_io_request(bp, cp); 180 while ((bp->bio_flags & BIO_DONE) == 0) { 181 mtx_lock(&Giant); 182 tsleep(bp, 0, "setattr", hz / 10); 183 mtx_unlock(&Giant); 184 } 185 error = bp->bio_error; 186 g_destroy_bio(bp); 187 if (error == EBUSY) 188 tsleep(&error, 0, "setattr_busy", hz); 189 } while(error == EBUSY); 190 return (error); 191 } 192 193 194 int 195 g_io_getattr(char *attr, struct g_consumer *cp, int *len, void *ptr, struct thread *tp __unused) 196 { 197 struct bio *bp; 198 int error; 199 200 g_trace(G_T_BIO, "bio_getattr(%s)", attr); 201 do { 202 bp = g_new_bio(); 203 bp->bio_cmd = BIO_GETATTR; 204 bp->bio_done = NULL; 205 bp->bio_attribute = attr; 206 bp->bio_length = *len; 207 bp->bio_data = ptr; 208 g_io_request(bp, cp); 209 while ((bp->bio_flags & BIO_DONE) == 0) { 210 mtx_lock(&Giant); 211 tsleep(bp, 0, "getattr", hz / 10); 212 mtx_unlock(&Giant); 213 } 214 *len = bp->bio_completed; 215 error = bp->bio_error; 216 g_destroy_bio(bp); 217 if (error == EBUSY) 218 tsleep(&error, 0, "getattr_busy", hz); 219 220 } while(error == EBUSY); 221 return (error); 222 } 223 224 void 225 g_io_request(struct bio *bp, struct g_consumer *cp) 226 { 227 int error; 228 229 KASSERT(cp != NULL, ("bio_request on thin air")); 230 error = 0; 231 bp->bio_from = cp; 232 bp->bio_to = cp->provider; 233 234 /* begin_stats(&bp->stats); */ 235 236 atomic_add_int(&cp->biocount, 1); 237 if (bp->bio_to == NULL) 238 error = ENXIO; 239 if (!error) { 240 switch(bp->bio_cmd) { 241 case BIO_READ: 242 case BIO_GETATTR: 243 if (cp->acr == 0) 244 error = EPERM; 245 break; 246 case BIO_WRITE: 247 if (cp->acw == 0) 248 error = EPERM; 249 break; 250 case BIO_SETATTR: 251 case BIO_DELETE: 252 case BIO_FORMAT: 253 if ((cp->acw == 0) || (cp->ace == 0)) 254 error = EPERM; 255 break; 256 default: 257 error = EPERM; 258 break; 259 } 260 } 261 /* if provider is marked for error, don't disturb */ 262 if (!error) 263 error = bp->bio_to->error; 264 if (error) { 265 bp->bio_error = error; 266 /* finish_stats(&bp->stats); */ 267 268 g_trace(G_T_BIO, 269 "bio_request(%p) from %p(%s) to %p(%s) cmd %d error %d\n", 270 bp, bp->bio_from, bp->bio_from->geom->name, 271 bp->bio_to, bp->bio_to->name, bp->bio_cmd, bp->bio_error); 272 g_bioq_enqueue_tail(bp, &g_bio_run_up); 273 mtx_lock(&Giant); 274 wakeup(&g_wait_up); 275 mtx_unlock(&Giant); 276 } else { 277 g_trace(G_T_BIO, "bio_request(%p) from %p(%s) to %p(%s) cmd %d", 278 bp, bp->bio_from, bp->bio_from->geom->name, 279 bp->bio_to, bp->bio_to->name, bp->bio_cmd); 280 g_bioq_enqueue_tail(bp, &g_bio_run_down); 281 mtx_lock(&Giant); 282 wakeup(&g_wait_down); 283 mtx_unlock(&Giant); 284 } 285 } 286 287 void 288 g_io_deliver(struct bio *bp) 289 { 290 291 g_trace(G_T_BIO, 292 "g_io_deliver(%p) from %p(%s) to %p(%s) cmd %d error %d", 293 bp, bp->bio_from, bp->bio_from->geom->name, 294 bp->bio_to, bp->bio_to->name, bp->bio_cmd, bp->bio_error); 295 /* finish_stats(&bp->stats); */ 296 297 g_bioq_enqueue_tail(bp, &g_bio_run_up); 298 299 mtx_lock(&Giant); 300 wakeup(&g_wait_up); 301 mtx_unlock(&Giant); 302 } 303 304 void 305 g_io_schedule_down(struct thread *tp __unused) 306 { 307 struct bio *bp; 308 309 for(;;) { 310 bp = g_bioq_first(&g_bio_run_down); 311 if (bp == NULL) 312 break; 313 bp->bio_to->geom->start(bp); 314 } 315 } 316 317 void 318 g_io_schedule_up(struct thread *tp __unused) 319 { 320 struct bio *bp; 321 struct g_consumer *cp; 322 323 for(;;) { 324 bp = g_bioq_first(&g_bio_run_up); 325 if (bp == NULL) 326 break; 327 328 cp = bp->bio_from; 329 330 bp->bio_flags |= BIO_DONE; 331 atomic_add_int(&cp->biocount, -1); 332 if (bp->bio_done != NULL) { 333 bp->bio_done(bp); 334 } else { 335 mtx_lock(&Giant); 336 wakeup(bp); 337 mtx_unlock(&Giant); 338 } 339 } 340 } 341 342 void * 343 g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error) 344 { 345 struct bio *bp; 346 void *ptr; 347 int errorc; 348 349 do { 350 bp = g_new_bio(); 351 bp->bio_cmd = BIO_READ; 352 bp->bio_done = NULL; 353 bp->bio_offset = offset; 354 bp->bio_length = length; 355 ptr = g_malloc(length, M_WAITOK); 356 bp->bio_data = ptr; 357 g_io_request(bp, cp); 358 while ((bp->bio_flags & BIO_DONE) == 0) { 359 mtx_lock(&Giant); 360 tsleep(bp, 0, "g_read_data", hz / 10); 361 mtx_unlock(&Giant); 362 } 363 errorc = bp->bio_error; 364 if (error != NULL) 365 *error = errorc; 366 g_destroy_bio(bp); 367 if (errorc) { 368 g_free(ptr); 369 ptr = NULL; 370 } 371 if (errorc == EBUSY) 372 tsleep(&errorc, 0, "g_read_data_busy", hz); 373 } while (errorc == EBUSY); 374 return (ptr); 375 } 376