| 1 | /* $NetBSD: subr_extent.c,v 1.79 2015/08/24 22:50:32 pooka Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1996, 1998, 2007 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Jason R. Thorpe and Matthias Drochner. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | /* |
| 33 | * General purpose extent manager. |
| 34 | */ |
| 35 | |
| 36 | #include <sys/cdefs.h> |
| 37 | __KERNEL_RCSID(0, "$NetBSD: subr_extent.c,v 1.79 2015/08/24 22:50:32 pooka Exp $" ); |
| 38 | |
| 39 | #ifdef _KERNEL |
| 40 | #ifdef _KERNEL_OPT |
| 41 | #include "opt_lockdebug.h" |
| 42 | #endif |
| 43 | |
| 44 | #include <sys/param.h> |
| 45 | #include <sys/extent.h> |
| 46 | #include <sys/kmem.h> |
| 47 | #include <sys/pool.h> |
| 48 | #include <sys/time.h> |
| 49 | #include <sys/systm.h> |
| 50 | #include <sys/proc.h> |
| 51 | |
| 52 | #include <uvm/uvm_extern.h> |
| 53 | |
| 54 | #elif defined(_EXTENT_TESTING) |
| 55 | |
| 56 | /* |
| 57 | * user-land definitions, so it can fit into a testing harness. |
| 58 | */ |
| 59 | #include <sys/param.h> |
| 60 | #include <sys/pool.h> |
| 61 | #include <sys/extent.h> |
| 62 | |
| 63 | #include <errno.h> |
| 64 | #include <stdlib.h> |
| 65 | #include <stdio.h> |
| 66 | #include <string.h> |
| 67 | |
| 68 | /* |
| 69 | * Use multi-line #defines to avoid screwing up the kernel tags file; |
| 70 | * without this, ctags produces a tags file where panic() shows up |
| 71 | * in subr_extent.c rather than subr_prf.c. |
| 72 | */ |
| 73 | #define \ |
| 74 | kmem_alloc(s, flags) malloc(s) |
| 75 | #define \ |
| 76 | kmem_free(p, s) free(p) |
| 77 | #define \ |
| 78 | cv_wait_sig(cv, lock) (EWOULDBLOCK) |
| 79 | #define \ |
| 80 | pool_get(pool, flags) kmem_alloc((pool)->pr_size,0) |
| 81 | #define \ |
| 82 | pool_put(pool, rp) kmem_free(rp,0) |
| 83 | #define \ |
| 84 | panic(a) printf(a) |
| 85 | #define mutex_init(a, b, c) |
| 86 | #define mutex_destroy(a) |
| 87 | #define mutex_enter(l) |
| 88 | #define mutex_exit(l) |
| 89 | #define cv_wait(cv, lock) |
| 90 | #define cv_broadcast(cv) |
| 91 | #define cv_init(a, b) |
| 92 | #define cv_destroy(a) |
| 93 | #define KMEM_IS_RUNNING (1) |
| 94 | #define IPL_VM (0) |
| 95 | #define MUTEX_DEFAULT (0) |
| 96 | #endif |
| 97 | |
| 98 | static struct pool expool; |
| 99 | |
| 100 | /* |
| 101 | * Macro to align to an arbitrary power-of-two boundary. |
| 102 | */ |
| 103 | #define EXTENT_ALIGN(_start, _align, _skew) \ |
| 104 | (((((_start) - (_skew)) + ((_align) - 1)) & (-(_align))) + (_skew)) |
| 105 | |
| 106 | /* |
| 107 | * Create the extent_region pool. |
| 108 | */ |
| 109 | void |
| 110 | extent_init(void) |
| 111 | { |
| 112 | |
| 113 | #if defined(_KERNEL) |
| 114 | pool_init(&expool, sizeof(struct extent_region), 0, 0, 0, |
| 115 | "extent" , NULL, IPL_VM); |
| 116 | #else |
| 117 | expool.pr_size = sizeof(struct extent_region); |
| 118 | #endif |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * Allocate an extent region descriptor. EXTENT MUST NOT BE LOCKED. |
| 123 | * We will handle any locking we may need. |
| 124 | */ |
| 125 | static struct extent_region * |
| 126 | extent_alloc_region_descriptor(struct extent *ex, int flags) |
| 127 | { |
| 128 | struct extent_region *rp; |
| 129 | int exflags, error; |
| 130 | |
| 131 | /* |
| 132 | * XXX Make a static, create-time flags word, so we don't |
| 133 | * XXX have to lock to read it! |
| 134 | */ |
| 135 | mutex_enter(&ex->ex_lock); |
| 136 | exflags = ex->ex_flags; |
| 137 | mutex_exit(&ex->ex_lock); |
| 138 | |
| 139 | if (exflags & EXF_FIXED) { |
| 140 | struct extent_fixed *fex = (struct extent_fixed *)ex; |
| 141 | |
| 142 | mutex_enter(&ex->ex_lock); |
| 143 | for (;;) { |
| 144 | if ((rp = LIST_FIRST(&fex->fex_freelist)) != NULL) { |
| 145 | /* |
| 146 | * Don't muck with flags after pulling it off |
| 147 | * the freelist; it may have been dynamically |
| 148 | * allocated, and kindly given to us. We |
| 149 | * need to remember that information. |
| 150 | */ |
| 151 | LIST_REMOVE(rp, er_link); |
| 152 | mutex_exit(&ex->ex_lock); |
| 153 | return (rp); |
| 154 | } |
| 155 | if (flags & EX_MALLOCOK) { |
| 156 | mutex_exit(&ex->ex_lock); |
| 157 | goto alloc; |
| 158 | } |
| 159 | if ((flags & EX_WAITOK) == 0) { |
| 160 | mutex_exit(&ex->ex_lock); |
| 161 | return (NULL); |
| 162 | } |
| 163 | ex->ex_flags |= EXF_FLWANTED; |
| 164 | if ((flags & EX_CATCH) != 0) |
| 165 | error = cv_wait_sig(&ex->ex_cv, &ex->ex_lock); |
| 166 | else { |
| 167 | cv_wait(&ex->ex_cv, &ex->ex_lock); |
| 168 | error = 0; |
| 169 | } |
| 170 | if (error != 0) { |
| 171 | mutex_exit(&ex->ex_lock); |
| 172 | return (NULL); |
| 173 | } |
| 174 | } |
| 175 | } |
| 176 | |
| 177 | alloc: |
| 178 | rp = pool_get(&expool, (flags & EX_WAITOK) ? PR_WAITOK : 0); |
| 179 | |
| 180 | if (rp != NULL) |
| 181 | rp->er_flags = ER_ALLOC; |
| 182 | |
| 183 | return (rp); |
| 184 | } |
| 185 | |
| 186 | /* |
| 187 | * Free an extent region descriptor. EXTENT _MUST_ BE LOCKED! |
| 188 | */ |
| 189 | static void |
| 190 | extent_free_region_descriptor(struct extent *ex, struct extent_region *rp) |
| 191 | { |
| 192 | |
| 193 | if (ex->ex_flags & EXF_FIXED) { |
| 194 | struct extent_fixed *fex = (struct extent_fixed *)ex; |
| 195 | |
| 196 | /* |
| 197 | * If someone's waiting for a region descriptor, |
| 198 | * be nice and give them this one, rather than |
| 199 | * just free'ing it back to the system. |
| 200 | */ |
| 201 | if (rp->er_flags & ER_ALLOC) { |
| 202 | if (ex->ex_flags & EXF_FLWANTED) { |
| 203 | /* Clear all but ER_ALLOC flag. */ |
| 204 | rp->er_flags = ER_ALLOC; |
| 205 | LIST_INSERT_HEAD(&fex->fex_freelist, rp, |
| 206 | er_link); |
| 207 | goto wake_em_up; |
| 208 | } else |
| 209 | pool_put(&expool, rp); |
| 210 | } else { |
| 211 | /* Clear all flags. */ |
| 212 | rp->er_flags = 0; |
| 213 | LIST_INSERT_HEAD(&fex->fex_freelist, rp, er_link); |
| 214 | } |
| 215 | |
| 216 | wake_em_up: |
| 217 | ex->ex_flags &= ~EXF_FLWANTED; |
| 218 | cv_broadcast(&ex->ex_cv); |
| 219 | return; |
| 220 | } |
| 221 | |
| 222 | /* |
| 223 | * We know it's dynamically allocated if we get here. |
| 224 | */ |
| 225 | pool_put(&expool, rp); |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * Allocate and initialize an extent map. |
| 230 | */ |
| 231 | struct extent * |
| 232 | extent_create(const char *name, u_long start, u_long end, |
| 233 | void *storage, size_t storagesize, int flags) |
| 234 | { |
| 235 | struct extent *ex; |
| 236 | char *cp = storage; |
| 237 | size_t sz = storagesize; |
| 238 | struct extent_region *rp; |
| 239 | int fixed_extent = (storage != NULL); |
| 240 | |
| 241 | #ifndef _KERNEL |
| 242 | extent_init(); |
| 243 | #endif |
| 244 | |
| 245 | #ifdef DIAGNOSTIC |
| 246 | /* Check arguments. */ |
| 247 | if (name == NULL) |
| 248 | panic("extent_create: name == NULL" ); |
| 249 | if (end < start) { |
| 250 | printf("extent_create: extent `%s', start 0x%lx, end 0x%lx\n" , |
| 251 | name, start, end); |
| 252 | panic("extent_create: end < start" ); |
| 253 | } |
| 254 | if (fixed_extent && (storagesize < sizeof(struct extent_fixed))) |
| 255 | panic("extent_create: fixed extent, bad storagesize 0x%lx" , |
| 256 | (u_long)storagesize); |
| 257 | if (fixed_extent == 0 && (storagesize != 0 || storage != NULL)) |
| 258 | panic("extent_create: storage provided for non-fixed" ); |
| 259 | #endif |
| 260 | |
| 261 | /* Allocate extent descriptor. */ |
| 262 | if (fixed_extent) { |
| 263 | struct extent_fixed *fex; |
| 264 | |
| 265 | memset(storage, 0, storagesize); |
| 266 | |
| 267 | /* |
| 268 | * Align all descriptors on "long" boundaries. |
| 269 | */ |
| 270 | fex = (struct extent_fixed *)cp; |
| 271 | ex = (struct extent *)fex; |
| 272 | cp += ALIGN(sizeof(struct extent_fixed)); |
| 273 | sz -= ALIGN(sizeof(struct extent_fixed)); |
| 274 | fex->fex_storage = storage; |
| 275 | fex->fex_storagesize = storagesize; |
| 276 | |
| 277 | /* |
| 278 | * In a fixed extent, we have to pre-allocate region |
| 279 | * descriptors and place them in the extent's freelist. |
| 280 | */ |
| 281 | LIST_INIT(&fex->fex_freelist); |
| 282 | while (sz >= ALIGN(sizeof(struct extent_region))) { |
| 283 | rp = (struct extent_region *)cp; |
| 284 | cp += ALIGN(sizeof(struct extent_region)); |
| 285 | sz -= ALIGN(sizeof(struct extent_region)); |
| 286 | LIST_INSERT_HEAD(&fex->fex_freelist, rp, er_link); |
| 287 | } |
| 288 | } else { |
| 289 | ex = kmem_alloc(sizeof(*ex), |
| 290 | (flags & EX_WAITOK) ? KM_SLEEP : KM_NOSLEEP); |
| 291 | if (ex == NULL) |
| 292 | return (NULL); |
| 293 | } |
| 294 | |
| 295 | /* Fill in the extent descriptor and return it to the caller. */ |
| 296 | mutex_init(&ex->ex_lock, MUTEX_DEFAULT, IPL_VM); |
| 297 | cv_init(&ex->ex_cv, "extent" ); |
| 298 | LIST_INIT(&ex->ex_regions); |
| 299 | ex->ex_name = name; |
| 300 | ex->ex_start = start; |
| 301 | ex->ex_end = end; |
| 302 | ex->ex_flags = 0; |
| 303 | if (fixed_extent) |
| 304 | ex->ex_flags |= EXF_FIXED; |
| 305 | if (flags & EX_NOCOALESCE) |
| 306 | ex->ex_flags |= EXF_NOCOALESCE; |
| 307 | return (ex); |
| 308 | } |
| 309 | |
| 310 | /* |
| 311 | * Destroy an extent map. |
| 312 | * Since we're freeing the data, there can't be any references |
| 313 | * so we don't need any locking. |
| 314 | */ |
| 315 | void |
| 316 | extent_destroy(struct extent *ex) |
| 317 | { |
| 318 | struct extent_region *rp, *orp; |
| 319 | |
| 320 | #ifdef DIAGNOSTIC |
| 321 | /* Check arguments. */ |
| 322 | if (ex == NULL) |
| 323 | panic("extent_destroy: NULL extent" ); |
| 324 | #endif |
| 325 | |
| 326 | /* Free all region descriptors in extent. */ |
| 327 | for (rp = LIST_FIRST(&ex->ex_regions); rp != NULL; ) { |
| 328 | orp = rp; |
| 329 | rp = LIST_NEXT(rp, er_link); |
| 330 | LIST_REMOVE(orp, er_link); |
| 331 | extent_free_region_descriptor(ex, orp); |
| 332 | } |
| 333 | |
| 334 | cv_destroy(&ex->ex_cv); |
| 335 | mutex_destroy(&ex->ex_lock); |
| 336 | |
| 337 | /* If we're not a fixed extent, free the extent descriptor itself. */ |
| 338 | if ((ex->ex_flags & EXF_FIXED) == 0) |
| 339 | kmem_free(ex, sizeof(*ex)); |
| 340 | } |
| 341 | |
| 342 | /* |
| 343 | * Insert a region descriptor into the sorted region list after the |
| 344 | * entry "after" or at the head of the list (if "after" is NULL). |
| 345 | * The region descriptor we insert is passed in "rp". We must |
| 346 | * allocate the region descriptor before calling this function! |
| 347 | * If we don't need the region descriptor, it will be freed here. |
| 348 | */ |
| 349 | static void |
| 350 | extent_insert_and_optimize(struct extent *ex, u_long start, u_long size, |
| 351 | int flags, struct extent_region *after, struct extent_region *rp) |
| 352 | { |
| 353 | struct extent_region *nextr; |
| 354 | int appended = 0; |
| 355 | |
| 356 | if (after == NULL) { |
| 357 | /* |
| 358 | * We're the first in the region list. If there's |
| 359 | * a region after us, attempt to coalesce to save |
| 360 | * descriptor overhead. |
| 361 | */ |
| 362 | if (((ex->ex_flags & EXF_NOCOALESCE) == 0) && |
| 363 | (LIST_FIRST(&ex->ex_regions) != NULL) && |
| 364 | ((start + size) == LIST_FIRST(&ex->ex_regions)->er_start)) { |
| 365 | /* |
| 366 | * We can coalesce. Prepend us to the first region. |
| 367 | */ |
| 368 | LIST_FIRST(&ex->ex_regions)->er_start = start; |
| 369 | extent_free_region_descriptor(ex, rp); |
| 370 | return; |
| 371 | } |
| 372 | |
| 373 | /* |
| 374 | * Can't coalesce. Fill in the region descriptor |
| 375 | * in, and insert us at the head of the region list. |
| 376 | */ |
| 377 | rp->er_start = start; |
| 378 | rp->er_end = start + (size - 1); |
| 379 | LIST_INSERT_HEAD(&ex->ex_regions, rp, er_link); |
| 380 | return; |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * If EXF_NOCOALESCE is set, coalescing is disallowed. |
| 385 | */ |
| 386 | if (ex->ex_flags & EXF_NOCOALESCE) |
| 387 | goto cant_coalesce; |
| 388 | |
| 389 | /* |
| 390 | * Attempt to coalesce with the region before us. |
| 391 | */ |
| 392 | if ((after->er_end + 1) == start) { |
| 393 | /* |
| 394 | * We can coalesce. Append ourselves and make |
| 395 | * note of it. |
| 396 | */ |
| 397 | after->er_end = start + (size - 1); |
| 398 | appended = 1; |
| 399 | } |
| 400 | |
| 401 | /* |
| 402 | * Attempt to coalesce with the region after us. |
| 403 | */ |
| 404 | if ((LIST_NEXT(after, er_link) != NULL) && |
| 405 | ((start + size) == LIST_NEXT(after, er_link)->er_start)) { |
| 406 | /* |
| 407 | * We can coalesce. Note that if we appended ourselves |
| 408 | * to the previous region, we exactly fit the gap, and |
| 409 | * can free the "next" region descriptor. |
| 410 | */ |
| 411 | if (appended) { |
| 412 | /* |
| 413 | * Yup, we can free it up. |
| 414 | */ |
| 415 | after->er_end = LIST_NEXT(after, er_link)->er_end; |
| 416 | nextr = LIST_NEXT(after, er_link); |
| 417 | LIST_REMOVE(nextr, er_link); |
| 418 | extent_free_region_descriptor(ex, nextr); |
| 419 | } else { |
| 420 | /* |
| 421 | * Nope, just prepend us to the next region. |
| 422 | */ |
| 423 | LIST_NEXT(after, er_link)->er_start = start; |
| 424 | } |
| 425 | |
| 426 | extent_free_region_descriptor(ex, rp); |
| 427 | return; |
| 428 | } |
| 429 | |
| 430 | /* |
| 431 | * We weren't able to coalesce with the next region, but |
| 432 | * we don't need to allocate a region descriptor if we |
| 433 | * appended ourselves to the previous region. |
| 434 | */ |
| 435 | if (appended) { |
| 436 | extent_free_region_descriptor(ex, rp); |
| 437 | return; |
| 438 | } |
| 439 | |
| 440 | cant_coalesce: |
| 441 | |
| 442 | /* |
| 443 | * Fill in the region descriptor and insert ourselves |
| 444 | * into the region list. |
| 445 | */ |
| 446 | rp->er_start = start; |
| 447 | rp->er_end = start + (size - 1); |
| 448 | LIST_INSERT_AFTER(after, rp, er_link); |
| 449 | } |
| 450 | |
| 451 | /* |
| 452 | * Allocate a specific region in an extent map. |
| 453 | */ |
| 454 | int |
| 455 | extent_alloc_region(struct extent *ex, u_long start, u_long size, int flags) |
| 456 | { |
| 457 | struct extent_region *rp, *last, *myrp; |
| 458 | u_long end = start + (size - 1); |
| 459 | int error; |
| 460 | |
| 461 | #ifdef DIAGNOSTIC |
| 462 | /* Check arguments. */ |
| 463 | if (ex == NULL) |
| 464 | panic("extent_alloc_region: NULL extent" ); |
| 465 | if (size < 1) { |
| 466 | printf("extent_alloc_region: extent `%s', size 0x%lx\n" , |
| 467 | ex->ex_name, size); |
| 468 | panic("extent_alloc_region: bad size" ); |
| 469 | } |
| 470 | if (end < start) { |
| 471 | printf( |
| 472 | "extent_alloc_region: extent `%s', start 0x%lx, size 0x%lx\n" , |
| 473 | ex->ex_name, start, size); |
| 474 | panic("extent_alloc_region: overflow" ); |
| 475 | } |
| 476 | #endif |
| 477 | #ifdef LOCKDEBUG |
| 478 | if (flags & EX_WAITSPACE) { |
| 479 | ASSERT_SLEEPABLE(); |
| 480 | } |
| 481 | #endif |
| 482 | |
| 483 | /* |
| 484 | * Make sure the requested region lies within the |
| 485 | * extent. |
| 486 | * |
| 487 | * We don't lock to check the range, because those values |
| 488 | * are never modified, and if another thread deletes the |
| 489 | * extent, we're screwed anyway. |
| 490 | */ |
| 491 | if ((start < ex->ex_start) || (end > ex->ex_end)) { |
| 492 | #ifdef DIAGNOSTIC |
| 493 | printf("extent_alloc_region: extent `%s' (0x%lx - 0x%lx)\n" , |
| 494 | ex->ex_name, ex->ex_start, ex->ex_end); |
| 495 | printf("extent_alloc_region: start 0x%lx, end 0x%lx\n" , |
| 496 | start, end); |
| 497 | panic("extent_alloc_region: region lies outside extent" ); |
| 498 | #else |
| 499 | return (EINVAL); |
| 500 | #endif |
| 501 | } |
| 502 | |
| 503 | /* |
| 504 | * Allocate the region descriptor. It will be freed later |
| 505 | * if we can coalesce with another region. Don't lock before |
| 506 | * here! This could block. |
| 507 | */ |
| 508 | myrp = extent_alloc_region_descriptor(ex, flags); |
| 509 | if (myrp == NULL) { |
| 510 | #ifdef DIAGNOSTIC |
| 511 | printf( |
| 512 | "extent_alloc_region: can't allocate region descriptor\n" ); |
| 513 | #endif |
| 514 | return (ENOMEM); |
| 515 | } |
| 516 | |
| 517 | mutex_enter(&ex->ex_lock); |
| 518 | alloc_start: |
| 519 | |
| 520 | /* |
| 521 | * Attempt to place ourselves in the desired area of the |
| 522 | * extent. We save ourselves some work by keeping the list sorted. |
| 523 | * In other words, if the start of the current region is greater |
| 524 | * than the end of our region, we don't have to search any further. |
| 525 | */ |
| 526 | |
| 527 | /* |
| 528 | * Keep a pointer to the last region we looked at so |
| 529 | * that we don't have to traverse the list again when |
| 530 | * we insert ourselves. If "last" is NULL when we |
| 531 | * finally insert ourselves, we go at the head of the |
| 532 | * list. See extent_insert_and_optimize() for details. |
| 533 | */ |
| 534 | last = NULL; |
| 535 | |
| 536 | LIST_FOREACH(rp, &ex->ex_regions, er_link) { |
| 537 | if (rp->er_start > end) { |
| 538 | /* |
| 539 | * We lie before this region and don't |
| 540 | * conflict. |
| 541 | */ |
| 542 | break; |
| 543 | } |
| 544 | |
| 545 | /* |
| 546 | * The current region begins before we end. |
| 547 | * Check for a conflict. |
| 548 | */ |
| 549 | if (rp->er_end >= start) { |
| 550 | /* |
| 551 | * We conflict. If we can (and want to) wait, |
| 552 | * do so. |
| 553 | */ |
| 554 | if (flags & EX_WAITSPACE) { |
| 555 | if ((flags & EX_CATCH) != 0) |
| 556 | error = cv_wait_sig(&ex->ex_cv, |
| 557 | &ex->ex_lock); |
| 558 | else { |
| 559 | cv_wait(&ex->ex_cv, &ex->ex_lock); |
| 560 | error = 0; |
| 561 | } |
| 562 | if (error == 0) |
| 563 | goto alloc_start; |
| 564 | mutex_exit(&ex->ex_lock); |
| 565 | } else { |
| 566 | mutex_exit(&ex->ex_lock); |
| 567 | error = EAGAIN; |
| 568 | } |
| 569 | extent_free_region_descriptor(ex, myrp); |
| 570 | return error; |
| 571 | } |
| 572 | /* |
| 573 | * We don't conflict, but this region lies before |
| 574 | * us. Keep a pointer to this region, and keep |
| 575 | * trying. |
| 576 | */ |
| 577 | last = rp; |
| 578 | } |
| 579 | |
| 580 | /* |
| 581 | * We don't conflict with any regions. "last" points |
| 582 | * to the region we fall after, or is NULL if we belong |
| 583 | * at the beginning of the region list. Insert ourselves. |
| 584 | */ |
| 585 | extent_insert_and_optimize(ex, start, size, flags, last, myrp); |
| 586 | mutex_exit(&ex->ex_lock); |
| 587 | return (0); |
| 588 | } |
| 589 | |
| 590 | /* |
| 591 | * Macro to check (x + y) <= z. This check is designed to fail |
| 592 | * if an overflow occurs. |
| 593 | */ |
| 594 | #define LE_OV(x, y, z) ((((x) + (y)) >= (x)) && (((x) + (y)) <= (z))) |
| 595 | |
| 596 | /* |
| 597 | * Allocate a region in an extent map subregion. |
| 598 | * |
| 599 | * If EX_FAST is specified, we return the first fit in the map. |
| 600 | * Otherwise, we try to minimize fragmentation by finding the |
| 601 | * smallest gap that will hold the request. |
| 602 | * |
| 603 | * The allocated region is aligned to "alignment", which must be |
| 604 | * a power of 2. |
| 605 | */ |
| 606 | int |
| 607 | extent_alloc_subregion1(struct extent *ex, u_long substart, u_long subend, |
| 608 | u_long size, u_long alignment, u_long skew, u_long boundary, |
| 609 | int flags, u_long *result) |
| 610 | { |
| 611 | struct extent_region *rp, *myrp, *last, *bestlast; |
| 612 | u_long newstart, newend, exend, beststart, bestovh, ovh; |
| 613 | u_long dontcross; |
| 614 | int error; |
| 615 | |
| 616 | #ifdef DIAGNOSTIC |
| 617 | /* |
| 618 | * Check arguments. |
| 619 | * |
| 620 | * We don't lock to check these, because these values |
| 621 | * are never modified, and if another thread deletes the |
| 622 | * extent, we're screwed anyway. |
| 623 | */ |
| 624 | if (ex == NULL) |
| 625 | panic("extent_alloc_subregion: NULL extent" ); |
| 626 | if (result == NULL) |
| 627 | panic("extent_alloc_subregion: NULL result pointer" ); |
| 628 | if ((substart < ex->ex_start) || (substart > ex->ex_end) || |
| 629 | (subend > ex->ex_end) || (subend < ex->ex_start)) { |
| 630 | printf("extent_alloc_subregion: extent `%s', ex_start 0x%lx, ex_end 0x%lx\n" , |
| 631 | ex->ex_name, ex->ex_start, ex->ex_end); |
| 632 | printf("extent_alloc_subregion: substart 0x%lx, subend 0x%lx\n" , |
| 633 | substart, subend); |
| 634 | panic("extent_alloc_subregion: bad subregion" ); |
| 635 | } |
| 636 | if ((size < 1) || ((size - 1) > (subend - substart))) { |
| 637 | printf("extent_alloc_subregion: extent `%s', size 0x%lx\n" , |
| 638 | ex->ex_name, size); |
| 639 | panic("extent_alloc_subregion: bad size" ); |
| 640 | } |
| 641 | if (alignment == 0) |
| 642 | panic("extent_alloc_subregion: bad alignment" ); |
| 643 | if (boundary && (boundary < size)) { |
| 644 | printf( |
| 645 | "extent_alloc_subregion: extent `%s', size 0x%lx, " |
| 646 | "boundary 0x%lx\n" , ex->ex_name, size, boundary); |
| 647 | panic("extent_alloc_subregion: bad boundary" ); |
| 648 | } |
| 649 | #endif |
| 650 | #ifdef LOCKDEBUG |
| 651 | if (flags & EX_WAITSPACE) { |
| 652 | ASSERT_SLEEPABLE(); |
| 653 | } |
| 654 | #endif |
| 655 | |
| 656 | /* |
| 657 | * Allocate the region descriptor. It will be freed later |
| 658 | * if we can coalesce with another region. Don't lock before |
| 659 | * here! This could block. |
| 660 | */ |
| 661 | myrp = extent_alloc_region_descriptor(ex, flags); |
| 662 | if (myrp == NULL) { |
| 663 | #ifdef DIAGNOSTIC |
| 664 | printf( |
| 665 | "extent_alloc_subregion: can't allocate region descriptor\n" ); |
| 666 | #endif |
| 667 | return (ENOMEM); |
| 668 | } |
| 669 | |
| 670 | alloc_start: |
| 671 | mutex_enter(&ex->ex_lock); |
| 672 | |
| 673 | /* |
| 674 | * Keep a pointer to the last region we looked at so |
| 675 | * that we don't have to traverse the list again when |
| 676 | * we insert ourselves. If "last" is NULL when we |
| 677 | * finally insert ourselves, we go at the head of the |
| 678 | * list. See extent_insert_and_optimize() for deatails. |
| 679 | */ |
| 680 | last = NULL; |
| 681 | |
| 682 | /* |
| 683 | * Keep track of size and location of the smallest |
| 684 | * chunk we fit in. |
| 685 | * |
| 686 | * Since the extent can be as large as the numeric range |
| 687 | * of the CPU (0 - 0xffffffff for 32-bit systems), the |
| 688 | * best overhead value can be the maximum unsigned integer. |
| 689 | * Thus, we initialize "bestovh" to 0, since we insert ourselves |
| 690 | * into the region list immediately on an exact match (which |
| 691 | * is the only case where "bestovh" would be set to 0). |
| 692 | */ |
| 693 | bestovh = 0; |
| 694 | beststart = 0; |
| 695 | bestlast = NULL; |
| 696 | |
| 697 | /* |
| 698 | * Keep track of end of free region. This is either the end of extent |
| 699 | * or the start of a region past the subend. |
| 700 | */ |
| 701 | exend = ex->ex_end; |
| 702 | |
| 703 | /* |
| 704 | * For N allocated regions, we must make (N + 1) |
| 705 | * checks for unallocated space. The first chunk we |
| 706 | * check is the area from the beginning of the subregion |
| 707 | * to the first allocated region after that point. |
| 708 | */ |
| 709 | newstart = EXTENT_ALIGN(substart, alignment, skew); |
| 710 | if (newstart < ex->ex_start) { |
| 711 | #ifdef DIAGNOSTIC |
| 712 | printf( |
| 713 | "extent_alloc_subregion: extent `%s' (0x%lx - 0x%lx), alignment 0x%lx\n" , |
| 714 | ex->ex_name, ex->ex_start, ex->ex_end, alignment); |
| 715 | mutex_exit(&ex->ex_lock); |
| 716 | panic("extent_alloc_subregion: overflow after alignment" ); |
| 717 | #else |
| 718 | extent_free_region_descriptor(ex, myrp); |
| 719 | mutex_exit(&ex->ex_lock); |
| 720 | return (EINVAL); |
| 721 | #endif |
| 722 | } |
| 723 | |
| 724 | /* |
| 725 | * Find the first allocated region that begins on or after |
| 726 | * the subregion start, advancing the "last" pointer along |
| 727 | * the way. |
| 728 | */ |
| 729 | LIST_FOREACH(rp, &ex->ex_regions, er_link) { |
| 730 | if (rp->er_start >= newstart) |
| 731 | break; |
| 732 | last = rp; |
| 733 | } |
| 734 | |
| 735 | /* |
| 736 | * Relocate the start of our candidate region to the end of |
| 737 | * the last allocated region (if there was one overlapping |
| 738 | * our subrange). |
| 739 | */ |
| 740 | if (last != NULL && last->er_end >= newstart) |
| 741 | newstart = EXTENT_ALIGN((last->er_end + 1), alignment, skew); |
| 742 | |
| 743 | for (; rp != NULL; rp = LIST_NEXT(rp, er_link)) { |
| 744 | /* |
| 745 | * If the region pasts the subend, bail out and see |
| 746 | * if we fit against the subend. |
| 747 | */ |
| 748 | if (rp->er_start > subend) { |
| 749 | exend = rp->er_start; |
| 750 | break; |
| 751 | } |
| 752 | |
| 753 | /* |
| 754 | * Check the chunk before "rp". Note that our |
| 755 | * comparison is safe from overflow conditions. |
| 756 | */ |
| 757 | if (LE_OV(newstart, size, rp->er_start)) { |
| 758 | /* |
| 759 | * Do a boundary check, if necessary. Note |
| 760 | * that a region may *begin* on the boundary, |
| 761 | * but it must end before the boundary. |
| 762 | */ |
| 763 | if (boundary) { |
| 764 | newend = newstart + (size - 1); |
| 765 | |
| 766 | /* |
| 767 | * Calculate the next boundary after the start |
| 768 | * of this region. |
| 769 | */ |
| 770 | dontcross = EXTENT_ALIGN(newstart+1, boundary, |
| 771 | (flags & EX_BOUNDZERO) ? 0 : ex->ex_start) |
| 772 | - 1; |
| 773 | |
| 774 | #if 0 |
| 775 | printf("newstart=%lx newend=%lx ex_start=%lx ex_end=%lx boundary=%lx dontcross=%lx\n" , |
| 776 | newstart, newend, ex->ex_start, ex->ex_end, |
| 777 | boundary, dontcross); |
| 778 | #endif |
| 779 | |
| 780 | /* Check for overflow */ |
| 781 | if (dontcross < ex->ex_start) |
| 782 | dontcross = ex->ex_end; |
| 783 | else if (newend > dontcross) { |
| 784 | /* |
| 785 | * Candidate region crosses boundary. |
| 786 | * Throw away the leading part and see |
| 787 | * if we still fit. |
| 788 | */ |
| 789 | newstart = dontcross + 1; |
| 790 | newend = newstart + (size - 1); |
| 791 | dontcross += boundary; |
| 792 | if (!LE_OV(newstart, size, rp->er_start)) |
| 793 | goto skip; |
| 794 | } |
| 795 | |
| 796 | /* |
| 797 | * If we run past the end of |
| 798 | * the extent or the boundary |
| 799 | * overflows, then the request |
| 800 | * can't fit. |
| 801 | */ |
| 802 | if (newstart + size - 1 > ex->ex_end || |
| 803 | dontcross < newstart) |
| 804 | goto fail; |
| 805 | } |
| 806 | |
| 807 | /* |
| 808 | * We would fit into this space. Calculate |
| 809 | * the overhead (wasted space). If we exactly |
| 810 | * fit, or we're taking the first fit, insert |
| 811 | * ourselves into the region list. |
| 812 | */ |
| 813 | ovh = rp->er_start - newstart - size; |
| 814 | if ((flags & EX_FAST) || (ovh == 0)) |
| 815 | goto found; |
| 816 | |
| 817 | /* |
| 818 | * Don't exactly fit, but check to see |
| 819 | * if we're better than any current choice. |
| 820 | */ |
| 821 | if ((bestovh == 0) || (ovh < bestovh)) { |
| 822 | bestovh = ovh; |
| 823 | beststart = newstart; |
| 824 | bestlast = last; |
| 825 | } |
| 826 | } |
| 827 | |
| 828 | skip: |
| 829 | /* |
| 830 | * Skip past the current region and check again. |
| 831 | */ |
| 832 | newstart = EXTENT_ALIGN((rp->er_end + 1), alignment, skew); |
| 833 | if (newstart < rp->er_end) { |
| 834 | /* |
| 835 | * Overflow condition. Don't error out, since |
| 836 | * we might have a chunk of space that we can |
| 837 | * use. |
| 838 | */ |
| 839 | goto fail; |
| 840 | } |
| 841 | |
| 842 | last = rp; |
| 843 | } |
| 844 | |
| 845 | /* |
| 846 | * The final check is from the current starting point to the |
| 847 | * end of the subregion. If there were no allocated regions, |
| 848 | * "newstart" is set to the beginning of the subregion, or |
| 849 | * just past the end of the last allocated region, adjusted |
| 850 | * for alignment in either case. |
| 851 | */ |
| 852 | if (LE_OV(newstart, (size - 1), subend)) { |
| 853 | /* |
| 854 | * Do a boundary check, if necessary. Note |
| 855 | * that a region may *begin* on the boundary, |
| 856 | * but it must end before the boundary. |
| 857 | */ |
| 858 | if (boundary) { |
| 859 | newend = newstart + (size - 1); |
| 860 | |
| 861 | /* |
| 862 | * Calculate the next boundary after the start |
| 863 | * of this region. |
| 864 | */ |
| 865 | dontcross = EXTENT_ALIGN(newstart+1, boundary, |
| 866 | (flags & EX_BOUNDZERO) ? 0 : ex->ex_start) |
| 867 | - 1; |
| 868 | |
| 869 | #if 0 |
| 870 | printf("newstart=%lx newend=%lx ex_start=%lx ex_end=%lx boundary=%lx dontcross=%lx\n" , |
| 871 | newstart, newend, ex->ex_start, ex->ex_end, |
| 872 | boundary, dontcross); |
| 873 | #endif |
| 874 | |
| 875 | /* Check for overflow */ |
| 876 | if (dontcross < ex->ex_start) |
| 877 | dontcross = ex->ex_end; |
| 878 | else if (newend > dontcross) { |
| 879 | /* |
| 880 | * Candidate region crosses boundary. |
| 881 | * Throw away the leading part and see |
| 882 | * if we still fit. |
| 883 | */ |
| 884 | newstart = dontcross + 1; |
| 885 | newend = newstart + (size - 1); |
| 886 | dontcross += boundary; |
| 887 | if (!LE_OV(newstart, (size - 1), subend)) |
| 888 | goto fail; |
| 889 | } |
| 890 | |
| 891 | /* |
| 892 | * If we run past the end of |
| 893 | * the extent or the boundary |
| 894 | * overflows, then the request |
| 895 | * can't fit. |
| 896 | */ |
| 897 | if (newstart + size - 1 > ex->ex_end || |
| 898 | dontcross < newstart) |
| 899 | goto fail; |
| 900 | } |
| 901 | |
| 902 | /* |
| 903 | * We would fit into this space. Calculate |
| 904 | * the overhead (wasted space). If we exactly |
| 905 | * fit, or we're taking the first fit, insert |
| 906 | * ourselves into the region list. |
| 907 | */ |
| 908 | ovh = exend - newstart - (size - 1); |
| 909 | if ((flags & EX_FAST) || (ovh == 0)) |
| 910 | goto found; |
| 911 | |
| 912 | /* |
| 913 | * Don't exactly fit, but check to see |
| 914 | * if we're better than any current choice. |
| 915 | */ |
| 916 | if ((bestovh == 0) || (ovh < bestovh)) { |
| 917 | bestovh = ovh; |
| 918 | beststart = newstart; |
| 919 | bestlast = last; |
| 920 | } |
| 921 | } |
| 922 | |
| 923 | fail: |
| 924 | /* |
| 925 | * One of the following two conditions have |
| 926 | * occurred: |
| 927 | * |
| 928 | * There is no chunk large enough to hold the request. |
| 929 | * |
| 930 | * If EX_FAST was not specified, there is not an |
| 931 | * exact match for the request. |
| 932 | * |
| 933 | * Note that if we reach this point and EX_FAST is |
| 934 | * set, then we know there is no space in the extent for |
| 935 | * the request. |
| 936 | */ |
| 937 | if (((flags & EX_FAST) == 0) && (bestovh != 0)) { |
| 938 | /* |
| 939 | * We have a match that's "good enough". |
| 940 | */ |
| 941 | newstart = beststart; |
| 942 | last = bestlast; |
| 943 | goto found; |
| 944 | } |
| 945 | |
| 946 | /* |
| 947 | * No space currently available. Wait for it to free up, |
| 948 | * if possible. |
| 949 | */ |
| 950 | if (flags & EX_WAITSPACE) { |
| 951 | if ((flags & EX_CATCH) != 0) { |
| 952 | error = cv_wait_sig(&ex->ex_cv, &ex->ex_lock); |
| 953 | } else { |
| 954 | cv_wait(&ex->ex_cv, &ex->ex_lock); |
| 955 | error = 0; |
| 956 | } |
| 957 | if (error == 0) |
| 958 | goto alloc_start; |
| 959 | mutex_exit(&ex->ex_lock); |
| 960 | } else { |
| 961 | mutex_exit(&ex->ex_lock); |
| 962 | error = EAGAIN; |
| 963 | } |
| 964 | |
| 965 | extent_free_region_descriptor(ex, myrp); |
| 966 | return error; |
| 967 | |
| 968 | found: |
| 969 | /* |
| 970 | * Insert ourselves into the region list. |
| 971 | */ |
| 972 | extent_insert_and_optimize(ex, newstart, size, flags, last, myrp); |
| 973 | mutex_exit(&ex->ex_lock); |
| 974 | *result = newstart; |
| 975 | return (0); |
| 976 | } |
| 977 | |
| 978 | int |
| 979 | extent_alloc_subregion(struct extent *ex, u_long start, u_long end, u_long size, |
| 980 | u_long alignment, u_long boundary, int flags, u_long *result) |
| 981 | { |
| 982 | |
| 983 | return (extent_alloc_subregion1(ex, start, end, size, alignment, |
| 984 | 0, boundary, flags, result)); |
| 985 | } |
| 986 | |
| 987 | int |
| 988 | extent_alloc(struct extent *ex, u_long size, u_long alignment, u_long boundary, |
| 989 | int flags, u_long *result) |
| 990 | { |
| 991 | |
| 992 | return (extent_alloc_subregion1(ex, ex->ex_start, ex->ex_end, |
| 993 | size, alignment, 0, boundary, |
| 994 | flags, result)); |
| 995 | } |
| 996 | |
| 997 | int |
| 998 | extent_alloc1(struct extent *ex, u_long size, u_long alignment, u_long skew, |
| 999 | u_long boundary, int flags, u_long *result) |
| 1000 | { |
| 1001 | |
| 1002 | return (extent_alloc_subregion1(ex, ex->ex_start, ex->ex_end, |
| 1003 | size, alignment, skew, boundary, |
| 1004 | flags, result)); |
| 1005 | } |
| 1006 | |
| 1007 | int |
| 1008 | extent_free(struct extent *ex, u_long start, u_long size, int flags) |
| 1009 | { |
| 1010 | struct extent_region *rp, *nrp = NULL; |
| 1011 | u_long end = start + (size - 1); |
| 1012 | int coalesce; |
| 1013 | |
| 1014 | #ifdef DIAGNOSTIC |
| 1015 | /* |
| 1016 | * Check arguments. |
| 1017 | * |
| 1018 | * We don't lock to check these, because these values |
| 1019 | * are never modified, and if another thread deletes the |
| 1020 | * extent, we're screwed anyway. |
| 1021 | */ |
| 1022 | if (ex == NULL) |
| 1023 | panic("extent_free: NULL extent" ); |
| 1024 | if ((start < ex->ex_start) || (end > ex->ex_end)) { |
| 1025 | extent_print(ex); |
| 1026 | printf("extent_free: extent `%s', start 0x%lx, size 0x%lx\n" , |
| 1027 | ex->ex_name, start, size); |
| 1028 | panic("extent_free: extent `%s', region not within extent" , |
| 1029 | ex->ex_name); |
| 1030 | } |
| 1031 | /* Check for an overflow. */ |
| 1032 | if (end < start) { |
| 1033 | extent_print(ex); |
| 1034 | printf("extent_free: extent `%s', start 0x%lx, size 0x%lx\n" , |
| 1035 | ex->ex_name, start, size); |
| 1036 | panic("extent_free: overflow" ); |
| 1037 | } |
| 1038 | #endif |
| 1039 | |
| 1040 | /* |
| 1041 | * If we're allowing coalescing, we must allocate a region |
| 1042 | * descriptor now, since it might block. |
| 1043 | * |
| 1044 | * XXX Make a static, create-time flags word, so we don't |
| 1045 | * XXX have to lock to read it! |
| 1046 | */ |
| 1047 | mutex_enter(&ex->ex_lock); |
| 1048 | coalesce = (ex->ex_flags & EXF_NOCOALESCE) == 0; |
| 1049 | mutex_exit(&ex->ex_lock); |
| 1050 | |
| 1051 | if (coalesce) { |
| 1052 | /* Allocate a region descriptor. */ |
| 1053 | nrp = extent_alloc_region_descriptor(ex, flags); |
| 1054 | if (nrp == NULL) |
| 1055 | return (ENOMEM); |
| 1056 | } |
| 1057 | |
| 1058 | mutex_enter(&ex->ex_lock); |
| 1059 | |
| 1060 | /* |
| 1061 | * Find region and deallocate. Several possibilities: |
| 1062 | * |
| 1063 | * 1. (start == er_start) && (end == er_end): |
| 1064 | * Free descriptor. |
| 1065 | * |
| 1066 | * 2. (start == er_start) && (end < er_end): |
| 1067 | * Adjust er_start. |
| 1068 | * |
| 1069 | * 3. (start > er_start) && (end == er_end): |
| 1070 | * Adjust er_end. |
| 1071 | * |
| 1072 | * 4. (start > er_start) && (end < er_end): |
| 1073 | * Fragment region. Requires descriptor alloc. |
| 1074 | * |
| 1075 | * Cases 2, 3, and 4 require that the EXF_NOCOALESCE flag |
| 1076 | * is not set. |
| 1077 | */ |
| 1078 | LIST_FOREACH(rp, &ex->ex_regions, er_link) { |
| 1079 | /* |
| 1080 | * Save ourselves some comparisons; does the current |
| 1081 | * region end before chunk to be freed begins? If so, |
| 1082 | * then we haven't found the appropriate region descriptor. |
| 1083 | */ |
| 1084 | if (rp->er_end < start) |
| 1085 | continue; |
| 1086 | |
| 1087 | /* |
| 1088 | * Save ourselves some traversal; does the current |
| 1089 | * region begin after the chunk to be freed ends? If so, |
| 1090 | * then we've already passed any possible region descriptors |
| 1091 | * that might have contained the chunk to be freed. |
| 1092 | */ |
| 1093 | if (rp->er_start > end) |
| 1094 | break; |
| 1095 | |
| 1096 | /* Case 1. */ |
| 1097 | if ((start == rp->er_start) && (end == rp->er_end)) { |
| 1098 | LIST_REMOVE(rp, er_link); |
| 1099 | extent_free_region_descriptor(ex, rp); |
| 1100 | goto done; |
| 1101 | } |
| 1102 | |
| 1103 | /* |
| 1104 | * The following cases all require that EXF_NOCOALESCE |
| 1105 | * is not set. |
| 1106 | */ |
| 1107 | if (!coalesce) |
| 1108 | continue; |
| 1109 | |
| 1110 | /* Case 2. */ |
| 1111 | if ((start == rp->er_start) && (end < rp->er_end)) { |
| 1112 | rp->er_start = (end + 1); |
| 1113 | goto done; |
| 1114 | } |
| 1115 | |
| 1116 | /* Case 3. */ |
| 1117 | if ((start > rp->er_start) && (end == rp->er_end)) { |
| 1118 | rp->er_end = (start - 1); |
| 1119 | goto done; |
| 1120 | } |
| 1121 | |
| 1122 | /* Case 4. */ |
| 1123 | if ((start > rp->er_start) && (end < rp->er_end)) { |
| 1124 | /* Fill in new descriptor. */ |
| 1125 | nrp->er_start = end + 1; |
| 1126 | nrp->er_end = rp->er_end; |
| 1127 | |
| 1128 | /* Adjust current descriptor. */ |
| 1129 | rp->er_end = start - 1; |
| 1130 | |
| 1131 | /* Insert new descriptor after current. */ |
| 1132 | LIST_INSERT_AFTER(rp, nrp, er_link); |
| 1133 | |
| 1134 | /* We used the new descriptor, so don't free it below */ |
| 1135 | nrp = NULL; |
| 1136 | goto done; |
| 1137 | } |
| 1138 | } |
| 1139 | |
| 1140 | /* Region not found, or request otherwise invalid. */ |
| 1141 | mutex_exit(&ex->ex_lock); |
| 1142 | extent_print(ex); |
| 1143 | printf("extent_free: start 0x%lx, end 0x%lx\n" , start, end); |
| 1144 | panic("extent_free: region not found" ); |
| 1145 | |
| 1146 | done: |
| 1147 | if (nrp != NULL) |
| 1148 | extent_free_region_descriptor(ex, nrp); |
| 1149 | cv_broadcast(&ex->ex_cv); |
| 1150 | mutex_exit(&ex->ex_lock); |
| 1151 | return (0); |
| 1152 | } |
| 1153 | |
| 1154 | void |
| 1155 | extent_print(struct extent *ex) |
| 1156 | { |
| 1157 | struct extent_region *rp; |
| 1158 | |
| 1159 | if (ex == NULL) |
| 1160 | panic("extent_print: NULL extent" ); |
| 1161 | |
| 1162 | mutex_enter(&ex->ex_lock); |
| 1163 | |
| 1164 | printf("extent `%s' (0x%lx - 0x%lx), flags = 0x%x\n" , ex->ex_name, |
| 1165 | ex->ex_start, ex->ex_end, ex->ex_flags); |
| 1166 | |
| 1167 | LIST_FOREACH(rp, &ex->ex_regions, er_link) |
| 1168 | printf(" 0x%lx - 0x%lx\n" , rp->er_start, rp->er_end); |
| 1169 | |
| 1170 | mutex_exit(&ex->ex_lock); |
| 1171 | } |
| 1172 | |