Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/kern/subr_vmem.c
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1 /*- 2 * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi, 3 * Copyright (c) 2013 EMC Corp. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 /* 29 * From: 30 * $NetBSD: vmem_impl.h,v 1.2 2013/01/29 21:26:24 para Exp $ 31 * $NetBSD: subr_vmem.c,v 1.83 2013/03/06 11:20:10 yamt Exp $ 32 */ 33 34 /* 35 * reference: 36 * - Magazines and Vmem: Extending the Slab Allocator 37 * to Many CPUs and Arbitrary Resources 38 * http://www.usenix.org/event/usenix01/bonwick.html 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD: releng/10.1/sys/kern/subr_vmem.c 260299 2014-01-04 23:31:34Z mav $"); 43 44 #include "opt_ddb.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/queue.h> 50 #include <sys/callout.h> 51 #include <sys/hash.h> 52 #include <sys/lock.h> 53 #include <sys/malloc.h> 54 #include <sys/mutex.h> 55 #include <sys/smp.h> 56 #include <sys/condvar.h> 57 #include <sys/sysctl.h> 58 #include <sys/taskqueue.h> 59 #include <sys/vmem.h> 60 61 #include "opt_vm.h" 62 63 #include <vm/uma.h> 64 #include <vm/vm.h> 65 #include <vm/pmap.h> 66 #include <vm/vm_map.h> 67 #include <vm/vm_object.h> 68 #include <vm/vm_kern.h> 69 #include <vm/vm_extern.h> 70 #include <vm/vm_param.h> 71 #include <vm/vm_pageout.h> 72 73 #define VMEM_OPTORDER 5 74 #define VMEM_OPTVALUE (1 << VMEM_OPTORDER) 75 #define VMEM_MAXORDER \ 76 (VMEM_OPTVALUE - 1 + sizeof(vmem_size_t) * NBBY - VMEM_OPTORDER) 77 78 #define VMEM_HASHSIZE_MIN 16 79 #define VMEM_HASHSIZE_MAX 131072 80 81 #define VMEM_QCACHE_IDX_MAX 16 82 83 #define VMEM_FITMASK (M_BESTFIT | M_FIRSTFIT) 84 85 #define VMEM_FLAGS \ 86 (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM | M_BESTFIT | M_FIRSTFIT) 87 88 #define BT_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM) 89 90 #define QC_NAME_MAX 16 91 92 /* 93 * Data structures private to vmem. 94 */ 95 MALLOC_DEFINE(M_VMEM, "vmem", "vmem internal structures"); 96 97 typedef struct vmem_btag bt_t; 98 99 TAILQ_HEAD(vmem_seglist, vmem_btag); 100 LIST_HEAD(vmem_freelist, vmem_btag); 101 LIST_HEAD(vmem_hashlist, vmem_btag); 102 103 struct qcache { 104 uma_zone_t qc_cache; 105 vmem_t *qc_vmem; 106 vmem_size_t qc_size; 107 char qc_name[QC_NAME_MAX]; 108 }; 109 typedef struct qcache qcache_t; 110 #define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache)) 111 112 #define VMEM_NAME_MAX 16 113 114 /* vmem arena */ 115 struct vmem { 116 struct mtx_padalign vm_lock; 117 struct cv vm_cv; 118 char vm_name[VMEM_NAME_MAX+1]; 119 LIST_ENTRY(vmem) vm_alllist; 120 struct vmem_hashlist vm_hash0[VMEM_HASHSIZE_MIN]; 121 struct vmem_freelist vm_freelist[VMEM_MAXORDER]; 122 struct vmem_seglist vm_seglist; 123 struct vmem_hashlist *vm_hashlist; 124 vmem_size_t vm_hashsize; 125 126 /* Constant after init */ 127 vmem_size_t vm_qcache_max; 128 vmem_size_t vm_quantum_mask; 129 vmem_size_t vm_import_quantum; 130 int vm_quantum_shift; 131 132 /* Written on alloc/free */ 133 LIST_HEAD(, vmem_btag) vm_freetags; 134 int vm_nfreetags; 135 int vm_nbusytag; 136 vmem_size_t vm_inuse; 137 vmem_size_t vm_size; 138 139 /* Used on import. */ 140 vmem_import_t *vm_importfn; 141 vmem_release_t *vm_releasefn; 142 void *vm_arg; 143 144 /* Space exhaustion callback. */ 145 vmem_reclaim_t *vm_reclaimfn; 146 147 /* quantum cache */ 148 qcache_t vm_qcache[VMEM_QCACHE_IDX_MAX]; 149 }; 150 151 /* boundary tag */ 152 struct vmem_btag { 153 TAILQ_ENTRY(vmem_btag) bt_seglist; 154 union { 155 LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */ 156 LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */ 157 } bt_u; 158 #define bt_hashlist bt_u.u_hashlist 159 #define bt_freelist bt_u.u_freelist 160 vmem_addr_t bt_start; 161 vmem_size_t bt_size; 162 int bt_type; 163 }; 164 165 #define BT_TYPE_SPAN 1 /* Allocated from importfn */ 166 #define BT_TYPE_SPAN_STATIC 2 /* vmem_add() or create. */ 167 #define BT_TYPE_FREE 3 /* Available space. */ 168 #define BT_TYPE_BUSY 4 /* Used space. */ 169 #define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC) 170 171 #define BT_END(bt) ((bt)->bt_start + (bt)->bt_size - 1) 172 173 #if defined(DIAGNOSTIC) 174 static int enable_vmem_check = 1; 175 SYSCTL_INT(_debug, OID_AUTO, vmem_check, CTLFLAG_RW, 176 &enable_vmem_check, 0, "Enable vmem check"); 177 static void vmem_check(vmem_t *); 178 #endif 179 180 static struct callout vmem_periodic_ch; 181 static int vmem_periodic_interval; 182 static struct task vmem_periodic_wk; 183 184 static struct mtx_padalign vmem_list_lock; 185 static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list); 186 187 /* ---- misc */ 188 #define VMEM_CONDVAR_INIT(vm, wchan) cv_init(&vm->vm_cv, wchan) 189 #define VMEM_CONDVAR_DESTROY(vm) cv_destroy(&vm->vm_cv) 190 #define VMEM_CONDVAR_WAIT(vm) cv_wait(&vm->vm_cv, &vm->vm_lock) 191 #define VMEM_CONDVAR_BROADCAST(vm) cv_broadcast(&vm->vm_cv) 192 193 194 #define VMEM_LOCK(vm) mtx_lock(&vm->vm_lock) 195 #define VMEM_TRYLOCK(vm) mtx_trylock(&vm->vm_lock) 196 #define VMEM_UNLOCK(vm) mtx_unlock(&vm->vm_lock) 197 #define VMEM_LOCK_INIT(vm, name) mtx_init(&vm->vm_lock, (name), NULL, MTX_DEF) 198 #define VMEM_LOCK_DESTROY(vm) mtx_destroy(&vm->vm_lock) 199 #define VMEM_ASSERT_LOCKED(vm) mtx_assert(&vm->vm_lock, MA_OWNED); 200 201 #define VMEM_ALIGNUP(addr, align) (-(-(addr) & -(align))) 202 203 #define VMEM_CROSS_P(addr1, addr2, boundary) \ 204 ((((addr1) ^ (addr2)) & -(boundary)) != 0) 205 206 #define ORDER2SIZE(order) ((order) < VMEM_OPTVALUE ? ((order) + 1) : \ 207 (vmem_size_t)1 << ((order) - (VMEM_OPTVALUE - VMEM_OPTORDER - 1))) 208 #define SIZE2ORDER(size) ((size) <= VMEM_OPTVALUE ? ((size) - 1) : \ 209 (flsl(size) + (VMEM_OPTVALUE - VMEM_OPTORDER - 2))) 210 211 /* 212 * Maximum number of boundary tags that may be required to satisfy an 213 * allocation. Two may be required to import. Another two may be 214 * required to clip edges. 215 */ 216 #define BT_MAXALLOC 4 217 218 /* 219 * Max free limits the number of locally cached boundary tags. We 220 * just want to avoid hitting the zone allocator for every call. 221 */ 222 #define BT_MAXFREE (BT_MAXALLOC * 8) 223 224 /* Allocator for boundary tags. */ 225 static uma_zone_t vmem_bt_zone; 226 227 /* boot time arena storage. */ 228 static struct vmem kernel_arena_storage; 229 static struct vmem kmem_arena_storage; 230 static struct vmem buffer_arena_storage; 231 static struct vmem transient_arena_storage; 232 vmem_t *kernel_arena = &kernel_arena_storage; 233 vmem_t *kmem_arena = &kmem_arena_storage; 234 vmem_t *buffer_arena = &buffer_arena_storage; 235 vmem_t *transient_arena = &transient_arena_storage; 236 237 #ifdef DEBUG_MEMGUARD 238 static struct vmem memguard_arena_storage; 239 vmem_t *memguard_arena = &memguard_arena_storage; 240 #endif 241 242 /* 243 * Fill the vmem's boundary tag cache. We guarantee that boundary tag 244 * allocation will not fail once bt_fill() passes. To do so we cache 245 * at least the maximum possible tag allocations in the arena. 246 */ 247 static int 248 bt_fill(vmem_t *vm, int flags) 249 { 250 bt_t *bt; 251 252 VMEM_ASSERT_LOCKED(vm); 253 254 /* 255 * Only allow the kmem arena to dip into reserve tags. It is the 256 * vmem where new tags come from. 257 */ 258 flags &= BT_FLAGS; 259 if (vm != kmem_arena) 260 flags &= ~M_USE_RESERVE; 261 262 /* 263 * Loop until we meet the reserve. To minimize the lock shuffle 264 * and prevent simultaneous fills we first try a NOWAIT regardless 265 * of the caller's flags. Specify M_NOVM so we don't recurse while 266 * holding a vmem lock. 267 */ 268 while (vm->vm_nfreetags < BT_MAXALLOC) { 269 bt = uma_zalloc(vmem_bt_zone, 270 (flags & M_USE_RESERVE) | M_NOWAIT | M_NOVM); 271 if (bt == NULL) { 272 VMEM_UNLOCK(vm); 273 bt = uma_zalloc(vmem_bt_zone, flags); 274 VMEM_LOCK(vm); 275 if (bt == NULL && (flags & M_NOWAIT) != 0) 276 break; 277 } 278 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist); 279 vm->vm_nfreetags++; 280 } 281 282 if (vm->vm_nfreetags < BT_MAXALLOC) 283 return ENOMEM; 284 285 return 0; 286 } 287 288 /* 289 * Pop a tag off of the freetag stack. 290 */ 291 static bt_t * 292 bt_alloc(vmem_t *vm) 293 { 294 bt_t *bt; 295 296 VMEM_ASSERT_LOCKED(vm); 297 bt = LIST_FIRST(&vm->vm_freetags); 298 MPASS(bt != NULL); 299 LIST_REMOVE(bt, bt_freelist); 300 vm->vm_nfreetags--; 301 302 return bt; 303 } 304 305 /* 306 * Trim the per-vmem free list. Returns with the lock released to 307 * avoid allocator recursions. 308 */ 309 static void 310 bt_freetrim(vmem_t *vm, int freelimit) 311 { 312 LIST_HEAD(, vmem_btag) freetags; 313 bt_t *bt; 314 315 LIST_INIT(&freetags); 316 VMEM_ASSERT_LOCKED(vm); 317 while (vm->vm_nfreetags > freelimit) { 318 bt = LIST_FIRST(&vm->vm_freetags); 319 LIST_REMOVE(bt, bt_freelist); 320 vm->vm_nfreetags--; 321 LIST_INSERT_HEAD(&freetags, bt, bt_freelist); 322 } 323 VMEM_UNLOCK(vm); 324 while ((bt = LIST_FIRST(&freetags)) != NULL) { 325 LIST_REMOVE(bt, bt_freelist); 326 uma_zfree(vmem_bt_zone, bt); 327 } 328 } 329 330 static inline void 331 bt_free(vmem_t *vm, bt_t *bt) 332 { 333 334 VMEM_ASSERT_LOCKED(vm); 335 MPASS(LIST_FIRST(&vm->vm_freetags) != bt); 336 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist); 337 vm->vm_nfreetags++; 338 } 339 340 /* 341 * freelist[0] ... [1, 1] 342 * freelist[1] ... [2, 2] 343 * : 344 * freelist[29] ... [30, 30] 345 * freelist[30] ... [31, 31] 346 * freelist[31] ... [32, 63] 347 * freelist[33] ... [64, 127] 348 * : 349 * freelist[n] ... [(1 << (n - 26)), (1 << (n - 25)) - 1] 350 * : 351 */ 352 353 static struct vmem_freelist * 354 bt_freehead_tofree(vmem_t *vm, vmem_size_t size) 355 { 356 const vmem_size_t qsize = size >> vm->vm_quantum_shift; 357 const int idx = SIZE2ORDER(qsize); 358 359 MPASS(size != 0 && qsize != 0); 360 MPASS((size & vm->vm_quantum_mask) == 0); 361 MPASS(idx >= 0); 362 MPASS(idx < VMEM_MAXORDER); 363 364 return &vm->vm_freelist[idx]; 365 } 366 367 /* 368 * bt_freehead_toalloc: return the freelist for the given size and allocation 369 * strategy. 370 * 371 * For M_FIRSTFIT, return the list in which any blocks are large enough 372 * for the requested size. otherwise, return the list which can have blocks 373 * large enough for the requested size. 374 */ 375 static struct vmem_freelist * 376 bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, int strat) 377 { 378 const vmem_size_t qsize = size >> vm->vm_quantum_shift; 379 int idx = SIZE2ORDER(qsize); 380 381 MPASS(size != 0 && qsize != 0); 382 MPASS((size & vm->vm_quantum_mask) == 0); 383 384 if (strat == M_FIRSTFIT && ORDER2SIZE(idx) != qsize) { 385 idx++; 386 /* check too large request? */ 387 } 388 MPASS(idx >= 0); 389 MPASS(idx < VMEM_MAXORDER); 390 391 return &vm->vm_freelist[idx]; 392 } 393 394 /* ---- boundary tag hash */ 395 396 static struct vmem_hashlist * 397 bt_hashhead(vmem_t *vm, vmem_addr_t addr) 398 { 399 struct vmem_hashlist *list; 400 unsigned int hash; 401 402 hash = hash32_buf(&addr, sizeof(addr), 0); 403 list = &vm->vm_hashlist[hash % vm->vm_hashsize]; 404 405 return list; 406 } 407 408 static bt_t * 409 bt_lookupbusy(vmem_t *vm, vmem_addr_t addr) 410 { 411 struct vmem_hashlist *list; 412 bt_t *bt; 413 414 VMEM_ASSERT_LOCKED(vm); 415 list = bt_hashhead(vm, addr); 416 LIST_FOREACH(bt, list, bt_hashlist) { 417 if (bt->bt_start == addr) { 418 break; 419 } 420 } 421 422 return bt; 423 } 424 425 static void 426 bt_rembusy(vmem_t *vm, bt_t *bt) 427 { 428 429 VMEM_ASSERT_LOCKED(vm); 430 MPASS(vm->vm_nbusytag > 0); 431 vm->vm_inuse -= bt->bt_size; 432 vm->vm_nbusytag--; 433 LIST_REMOVE(bt, bt_hashlist); 434 } 435 436 static void 437 bt_insbusy(vmem_t *vm, bt_t *bt) 438 { 439 struct vmem_hashlist *list; 440 441 VMEM_ASSERT_LOCKED(vm); 442 MPASS(bt->bt_type == BT_TYPE_BUSY); 443 444 list = bt_hashhead(vm, bt->bt_start); 445 LIST_INSERT_HEAD(list, bt, bt_hashlist); 446 vm->vm_nbusytag++; 447 vm->vm_inuse += bt->bt_size; 448 } 449 450 /* ---- boundary tag list */ 451 452 static void 453 bt_remseg(vmem_t *vm, bt_t *bt) 454 { 455 456 TAILQ_REMOVE(&vm->vm_seglist, bt, bt_seglist); 457 bt_free(vm, bt); 458 } 459 460 static void 461 bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev) 462 { 463 464 TAILQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist); 465 } 466 467 static void 468 bt_insseg_tail(vmem_t *vm, bt_t *bt) 469 { 470 471 TAILQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist); 472 } 473 474 static void 475 bt_remfree(vmem_t *vm, bt_t *bt) 476 { 477 478 MPASS(bt->bt_type == BT_TYPE_FREE); 479 480 LIST_REMOVE(bt, bt_freelist); 481 } 482 483 static void 484 bt_insfree(vmem_t *vm, bt_t *bt) 485 { 486 struct vmem_freelist *list; 487 488 list = bt_freehead_tofree(vm, bt->bt_size); 489 LIST_INSERT_HEAD(list, bt, bt_freelist); 490 } 491 492 /* ---- vmem internal functions */ 493 494 /* 495 * Import from the arena into the quantum cache in UMA. 496 */ 497 static int 498 qc_import(void *arg, void **store, int cnt, int flags) 499 { 500 qcache_t *qc; 501 vmem_addr_t addr; 502 int i; 503 504 qc = arg; 505 flags |= M_BESTFIT; 506 for (i = 0; i < cnt; i++) { 507 if (vmem_xalloc(qc->qc_vmem, qc->qc_size, 0, 0, 0, 508 VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags, &addr) != 0) 509 break; 510 store[i] = (void *)addr; 511 /* Only guarantee one allocation. */ 512 flags &= ~M_WAITOK; 513 flags |= M_NOWAIT; 514 } 515 return i; 516 } 517 518 /* 519 * Release memory from the UMA cache to the arena. 520 */ 521 static void 522 qc_release(void *arg, void **store, int cnt) 523 { 524 qcache_t *qc; 525 int i; 526 527 qc = arg; 528 for (i = 0; i < cnt; i++) 529 vmem_xfree(qc->qc_vmem, (vmem_addr_t)store[i], qc->qc_size); 530 } 531 532 static void 533 qc_init(vmem_t *vm, vmem_size_t qcache_max) 534 { 535 qcache_t *qc; 536 vmem_size_t size; 537 int qcache_idx_max; 538 int i; 539 540 MPASS((qcache_max & vm->vm_quantum_mask) == 0); 541 qcache_idx_max = MIN(qcache_max >> vm->vm_quantum_shift, 542 VMEM_QCACHE_IDX_MAX); 543 vm->vm_qcache_max = qcache_idx_max << vm->vm_quantum_shift; 544 for (i = 0; i < qcache_idx_max; i++) { 545 qc = &vm->vm_qcache[i]; 546 size = (i + 1) << vm->vm_quantum_shift; 547 snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu", 548 vm->vm_name, size); 549 qc->qc_vmem = vm; 550 qc->qc_size = size; 551 qc->qc_cache = uma_zcache_create(qc->qc_name, size, 552 NULL, NULL, NULL, NULL, qc_import, qc_release, qc, 553 UMA_ZONE_VM); 554 MPASS(qc->qc_cache); 555 } 556 } 557 558 static void 559 qc_destroy(vmem_t *vm) 560 { 561 int qcache_idx_max; 562 int i; 563 564 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift; 565 for (i = 0; i < qcache_idx_max; i++) 566 uma_zdestroy(vm->vm_qcache[i].qc_cache); 567 } 568 569 static void 570 qc_drain(vmem_t *vm) 571 { 572 int qcache_idx_max; 573 int i; 574 575 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift; 576 for (i = 0; i < qcache_idx_max; i++) 577 zone_drain(vm->vm_qcache[i].qc_cache); 578 } 579 580 #ifndef UMA_MD_SMALL_ALLOC 581 582 static struct mtx_padalign vmem_bt_lock; 583 584 /* 585 * vmem_bt_alloc: Allocate a new page of boundary tags. 586 * 587 * On architectures with uma_small_alloc there is no recursion; no address 588 * space need be allocated to allocate boundary tags. For the others, we 589 * must handle recursion. Boundary tags are necessary to allocate new 590 * boundary tags. 591 * 592 * UMA guarantees that enough tags are held in reserve to allocate a new 593 * page of kva. We dip into this reserve by specifying M_USE_RESERVE only 594 * when allocating the page to hold new boundary tags. In this way the 595 * reserve is automatically filled by the allocation that uses the reserve. 596 * 597 * We still have to guarantee that the new tags are allocated atomically since 598 * many threads may try concurrently. The bt_lock provides this guarantee. 599 * We convert WAITOK allocations to NOWAIT and then handle the blocking here 600 * on failure. It's ok to return NULL for a WAITOK allocation as UMA will 601 * loop again after checking to see if we lost the race to allocate. 602 * 603 * There is a small race between vmem_bt_alloc() returning the page and the 604 * zone lock being acquired to add the page to the zone. For WAITOK 605 * allocations we just pause briefly. NOWAIT may experience a transient 606 * failure. To alleviate this we permit a small number of simultaneous 607 * fills to proceed concurrently so NOWAIT is less likely to fail unless 608 * we are really out of KVA. 609 */ 610 static void * 611 vmem_bt_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait) 612 { 613 vmem_addr_t addr; 614 615 *pflag = UMA_SLAB_KMEM; 616 617 /* 618 * Single thread boundary tag allocation so that the address space 619 * and memory are added in one atomic operation. 620 */ 621 mtx_lock(&vmem_bt_lock); 622 if (vmem_xalloc(kmem_arena, bytes, 0, 0, 0, VMEM_ADDR_MIN, 623 VMEM_ADDR_MAX, M_NOWAIT | M_NOVM | M_USE_RESERVE | M_BESTFIT, 624 &addr) == 0) { 625 if (kmem_back(kmem_object, addr, bytes, 626 M_NOWAIT | M_USE_RESERVE) == 0) { 627 mtx_unlock(&vmem_bt_lock); 628 return ((void *)addr); 629 } 630 vmem_xfree(kmem_arena, addr, bytes); 631 mtx_unlock(&vmem_bt_lock); 632 /* 633 * Out of memory, not address space. This may not even be 634 * possible due to M_USE_RESERVE page allocation. 635 */ 636 if (wait & M_WAITOK) 637 VM_WAIT; 638 return (NULL); 639 } 640 mtx_unlock(&vmem_bt_lock); 641 /* 642 * We're either out of address space or lost a fill race. 643 */ 644 if (wait & M_WAITOK) 645 pause("btalloc", 1); 646 647 return (NULL); 648 } 649 #endif 650 651 void 652 vmem_startup(void) 653 { 654 655 mtx_init(&vmem_list_lock, "vmem list lock", NULL, MTX_DEF); 656 vmem_bt_zone = uma_zcreate("vmem btag", 657 sizeof(struct vmem_btag), NULL, NULL, NULL, NULL, 658 UMA_ALIGN_PTR, UMA_ZONE_VM); 659 #ifndef UMA_MD_SMALL_ALLOC 660 mtx_init(&vmem_bt_lock, "btag lock", NULL, MTX_DEF); 661 uma_prealloc(vmem_bt_zone, BT_MAXALLOC); 662 /* 663 * Reserve enough tags to allocate new tags. We allow multiple 664 * CPUs to attempt to allocate new tags concurrently to limit 665 * false restarts in UMA. 666 */ 667 uma_zone_reserve(vmem_bt_zone, BT_MAXALLOC * (mp_ncpus + 1) / 2); 668 uma_zone_set_allocf(vmem_bt_zone, vmem_bt_alloc); 669 #endif 670 } 671 672 /* ---- rehash */ 673 674 static int 675 vmem_rehash(vmem_t *vm, vmem_size_t newhashsize) 676 { 677 bt_t *bt; 678 int i; 679 struct vmem_hashlist *newhashlist; 680 struct vmem_hashlist *oldhashlist; 681 vmem_size_t oldhashsize; 682 683 MPASS(newhashsize > 0); 684 685 newhashlist = malloc(sizeof(struct vmem_hashlist) * newhashsize, 686 M_VMEM, M_NOWAIT); 687 if (newhashlist == NULL) 688 return ENOMEM; 689 for (i = 0; i < newhashsize; i++) { 690 LIST_INIT(&newhashlist[i]); 691 } 692 693 VMEM_LOCK(vm); 694 oldhashlist = vm->vm_hashlist; 695 oldhashsize = vm->vm_hashsize; 696 vm->vm_hashlist = newhashlist; 697 vm->vm_hashsize = newhashsize; 698 if (oldhashlist == NULL) { 699 VMEM_UNLOCK(vm); 700 return 0; 701 } 702 for (i = 0; i < oldhashsize; i++) { 703 while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) { 704 bt_rembusy(vm, bt); 705 bt_insbusy(vm, bt); 706 } 707 } 708 VMEM_UNLOCK(vm); 709 710 if (oldhashlist != vm->vm_hash0) { 711 free(oldhashlist, M_VMEM); 712 } 713 714 return 0; 715 } 716 717 static void 718 vmem_periodic_kick(void *dummy) 719 { 720 721 taskqueue_enqueue(taskqueue_thread, &vmem_periodic_wk); 722 } 723 724 static void 725 vmem_periodic(void *unused, int pending) 726 { 727 vmem_t *vm; 728 vmem_size_t desired; 729 vmem_size_t current; 730 731 mtx_lock(&vmem_list_lock); 732 LIST_FOREACH(vm, &vmem_list, vm_alllist) { 733 #ifdef DIAGNOSTIC 734 /* Convenient time to verify vmem state. */ 735 if (enable_vmem_check == 1) { 736 VMEM_LOCK(vm); 737 vmem_check(vm); 738 VMEM_UNLOCK(vm); 739 } 740 #endif 741 desired = 1 << flsl(vm->vm_nbusytag); 742 desired = MIN(MAX(desired, VMEM_HASHSIZE_MIN), 743 VMEM_HASHSIZE_MAX); 744 current = vm->vm_hashsize; 745 746 /* Grow in powers of two. Shrink less aggressively. */ 747 if (desired >= current * 2 || desired * 4 <= current) 748 vmem_rehash(vm, desired); 749 } 750 mtx_unlock(&vmem_list_lock); 751 752 callout_reset(&vmem_periodic_ch, vmem_periodic_interval, 753 vmem_periodic_kick, NULL); 754 } 755 756 static void 757 vmem_start_callout(void *unused) 758 { 759 760 TASK_INIT(&vmem_periodic_wk, 0, vmem_periodic, NULL); 761 vmem_periodic_interval = hz * 10; 762 callout_init(&vmem_periodic_ch, CALLOUT_MPSAFE); 763 callout_reset(&vmem_periodic_ch, vmem_periodic_interval, 764 vmem_periodic_kick, NULL); 765 } 766 SYSINIT(vfs, SI_SUB_CONFIGURE, SI_ORDER_ANY, vmem_start_callout, NULL); 767 768 static void 769 vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int type) 770 { 771 bt_t *btspan; 772 bt_t *btfree; 773 774 MPASS(type == BT_TYPE_SPAN || type == BT_TYPE_SPAN_STATIC); 775 MPASS((size & vm->vm_quantum_mask) == 0); 776 777 btspan = bt_alloc(vm); 778 btspan->bt_type = type; 779 btspan->bt_start = addr; 780 btspan->bt_size = size; 781 bt_insseg_tail(vm, btspan); 782 783 btfree = bt_alloc(vm); 784 btfree->bt_type = BT_TYPE_FREE; 785 btfree->bt_start = addr; 786 btfree->bt_size = size; 787 bt_insseg(vm, btfree, btspan); 788 bt_insfree(vm, btfree); 789 790 vm->vm_size += size; 791 } 792 793 static void 794 vmem_destroy1(vmem_t *vm) 795 { 796 bt_t *bt; 797 798 /* 799 * Drain per-cpu quantum caches. 800 */ 801 qc_destroy(vm); 802 803 /* 804 * The vmem should now only contain empty segments. 805 */ 806 VMEM_LOCK(vm); 807 MPASS(vm->vm_nbusytag == 0); 808 809 while ((bt = TAILQ_FIRST(&vm->vm_seglist)) != NULL) 810 bt_remseg(vm, bt); 811 812 if (vm->vm_hashlist != NULL && vm->vm_hashlist != vm->vm_hash0) 813 free(vm->vm_hashlist, M_VMEM); 814 815 bt_freetrim(vm, 0); 816 817 VMEM_CONDVAR_DESTROY(vm); 818 VMEM_LOCK_DESTROY(vm); 819 free(vm, M_VMEM); 820 } 821 822 static int 823 vmem_import(vmem_t *vm, vmem_size_t size, vmem_size_t align, int flags) 824 { 825 vmem_addr_t addr; 826 int error; 827 828 if (vm->vm_importfn == NULL) 829 return EINVAL; 830 831 /* 832 * To make sure we get a span that meets the alignment we double it 833 * and add the size to the tail. This slightly overestimates. 834 */ 835 if (align != vm->vm_quantum_mask + 1) 836 size = (align * 2) + size; 837 size = roundup(size, vm->vm_import_quantum); 838 839 /* 840 * Hide MAXALLOC tags so we're guaranteed to be able to add this 841 * span and the tag we want to allocate from it. 842 */ 843 MPASS(vm->vm_nfreetags >= BT_MAXALLOC); 844 vm->vm_nfreetags -= BT_MAXALLOC; 845 VMEM_UNLOCK(vm); 846 error = (vm->vm_importfn)(vm->vm_arg, size, flags, &addr); 847 VMEM_LOCK(vm); 848 vm->vm_nfreetags += BT_MAXALLOC; 849 if (error) 850 return ENOMEM; 851 852 vmem_add1(vm, addr, size, BT_TYPE_SPAN); 853 854 return 0; 855 } 856 857 /* 858 * vmem_fit: check if a bt can satisfy the given restrictions. 859 * 860 * it's a caller's responsibility to ensure the region is big enough 861 * before calling us. 862 */ 863 static int 864 vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align, 865 vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr, 866 vmem_addr_t maxaddr, vmem_addr_t *addrp) 867 { 868 vmem_addr_t start; 869 vmem_addr_t end; 870 871 MPASS(size > 0); 872 MPASS(bt->bt_size >= size); /* caller's responsibility */ 873 874 /* 875 * XXX assumption: vmem_addr_t and vmem_size_t are 876 * unsigned integer of the same size. 877 */ 878 879 start = bt->bt_start; 880 if (start < minaddr) { 881 start = minaddr; 882 } 883 end = BT_END(bt); 884 if (end > maxaddr) 885 end = maxaddr; 886 if (start > end) 887 return (ENOMEM); 888 889 start = VMEM_ALIGNUP(start - phase, align) + phase; 890 if (start < bt->bt_start) 891 start += align; 892 if (VMEM_CROSS_P(start, start + size - 1, nocross)) { 893 MPASS(align < nocross); 894 start = VMEM_ALIGNUP(start - phase, nocross) + phase; 895 } 896 if (start <= end && end - start >= size - 1) { 897 MPASS((start & (align - 1)) == phase); 898 MPASS(!VMEM_CROSS_P(start, start + size - 1, nocross)); 899 MPASS(minaddr <= start); 900 MPASS(maxaddr == 0 || start + size - 1 <= maxaddr); 901 MPASS(bt->bt_start <= start); 902 MPASS(BT_END(bt) - start >= size - 1); 903 *addrp = start; 904 905 return (0); 906 } 907 return (ENOMEM); 908 } 909 910 /* 911 * vmem_clip: Trim the boundary tag edges to the requested start and size. 912 */ 913 static void 914 vmem_clip(vmem_t *vm, bt_t *bt, vmem_addr_t start, vmem_size_t size) 915 { 916 bt_t *btnew; 917 bt_t *btprev; 918 919 VMEM_ASSERT_LOCKED(vm); 920 MPASS(bt->bt_type == BT_TYPE_FREE); 921 MPASS(bt->bt_size >= size); 922 bt_remfree(vm, bt); 923 if (bt->bt_start != start) { 924 btprev = bt_alloc(vm); 925 btprev->bt_type = BT_TYPE_FREE; 926 btprev->bt_start = bt->bt_start; 927 btprev->bt_size = start - bt->bt_start; 928 bt->bt_start = start; 929 bt->bt_size -= btprev->bt_size; 930 bt_insfree(vm, btprev); 931 bt_insseg(vm, btprev, 932 TAILQ_PREV(bt, vmem_seglist, bt_seglist)); 933 } 934 MPASS(bt->bt_start == start); 935 if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) { 936 /* split */ 937 btnew = bt_alloc(vm); 938 btnew->bt_type = BT_TYPE_BUSY; 939 btnew->bt_start = bt->bt_start; 940 btnew->bt_size = size; 941 bt->bt_start = bt->bt_start + size; 942 bt->bt_size -= size; 943 bt_insfree(vm, bt); 944 bt_insseg(vm, btnew, 945 TAILQ_PREV(bt, vmem_seglist, bt_seglist)); 946 bt_insbusy(vm, btnew); 947 bt = btnew; 948 } else { 949 bt->bt_type = BT_TYPE_BUSY; 950 bt_insbusy(vm, bt); 951 } 952 MPASS(bt->bt_size >= size); 953 bt->bt_type = BT_TYPE_BUSY; 954 } 955 956 /* ---- vmem API */ 957 958 void 959 vmem_set_import(vmem_t *vm, vmem_import_t *importfn, 960 vmem_release_t *releasefn, void *arg, vmem_size_t import_quantum) 961 { 962 963 VMEM_LOCK(vm); 964 vm->vm_importfn = importfn; 965 vm->vm_releasefn = releasefn; 966 vm->vm_arg = arg; 967 vm->vm_import_quantum = import_quantum; 968 VMEM_UNLOCK(vm); 969 } 970 971 void 972 vmem_set_reclaim(vmem_t *vm, vmem_reclaim_t *reclaimfn) 973 { 974 975 VMEM_LOCK(vm); 976 vm->vm_reclaimfn = reclaimfn; 977 VMEM_UNLOCK(vm); 978 } 979 980 /* 981 * vmem_init: Initializes vmem arena. 982 */ 983 vmem_t * 984 vmem_init(vmem_t *vm, const char *name, vmem_addr_t base, vmem_size_t size, 985 vmem_size_t quantum, vmem_size_t qcache_max, int flags) 986 { 987 int i; 988 989 MPASS(quantum > 0); 990 MPASS((quantum & (quantum - 1)) == 0); 991 992 bzero(vm, sizeof(*vm)); 993 994 VMEM_CONDVAR_INIT(vm, name); 995 VMEM_LOCK_INIT(vm, name); 996 vm->vm_nfreetags = 0; 997 LIST_INIT(&vm->vm_freetags); 998 strlcpy(vm->vm_name, name, sizeof(vm->vm_name)); 999 vm->vm_quantum_mask = quantum - 1; 1000 vm->vm_quantum_shift = flsl(quantum) - 1; 1001 vm->vm_nbusytag = 0; 1002 vm->vm_size = 0; 1003 vm->vm_inuse = 0; 1004 qc_init(vm, qcache_max); 1005 1006 TAILQ_INIT(&vm->vm_seglist); 1007 for (i = 0; i < VMEM_MAXORDER; i++) { 1008 LIST_INIT(&vm->vm_freelist[i]); 1009 } 1010 memset(&vm->vm_hash0, 0, sizeof(vm->vm_hash0)); 1011 vm->vm_hashsize = VMEM_HASHSIZE_MIN; 1012 vm->vm_hashlist = vm->vm_hash0; 1013 1014 if (size != 0) { 1015 if (vmem_add(vm, base, size, flags) != 0) { 1016 vmem_destroy1(vm); 1017 return NULL; 1018 } 1019 } 1020 1021 mtx_lock(&vmem_list_lock); 1022 LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist); 1023 mtx_unlock(&vmem_list_lock); 1024 1025 return vm; 1026 } 1027 1028 /* 1029 * vmem_create: create an arena. 1030 */ 1031 vmem_t * 1032 vmem_create(const char *name, vmem_addr_t base, vmem_size_t size, 1033 vmem_size_t quantum, vmem_size_t qcache_max, int flags) 1034 { 1035 1036 vmem_t *vm; 1037 1038 vm = malloc(sizeof(*vm), M_VMEM, flags & (M_WAITOK|M_NOWAIT)); 1039 if (vm == NULL) 1040 return (NULL); 1041 if (vmem_init(vm, name, base, size, quantum, qcache_max, 1042 flags) == NULL) { 1043 free(vm, M_VMEM); 1044 return (NULL); 1045 } 1046 return (vm); 1047 } 1048 1049 void 1050 vmem_destroy(vmem_t *vm) 1051 { 1052 1053 mtx_lock(&vmem_list_lock); 1054 LIST_REMOVE(vm, vm_alllist); 1055 mtx_unlock(&vmem_list_lock); 1056 1057 vmem_destroy1(vm); 1058 } 1059 1060 vmem_size_t 1061 vmem_roundup_size(vmem_t *vm, vmem_size_t size) 1062 { 1063 1064 return (size + vm->vm_quantum_mask) & ~vm->vm_quantum_mask; 1065 } 1066 1067 /* 1068 * vmem_alloc: allocate resource from the arena. 1069 */ 1070 int 1071 vmem_alloc(vmem_t *vm, vmem_size_t size, int flags, vmem_addr_t *addrp) 1072 { 1073 const int strat __unused = flags & VMEM_FITMASK; 1074 qcache_t *qc; 1075 1076 flags &= VMEM_FLAGS; 1077 MPASS(size > 0); 1078 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT); 1079 if ((flags & M_NOWAIT) == 0) 1080 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_alloc"); 1081 1082 if (size <= vm->vm_qcache_max) { 1083 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift]; 1084 *addrp = (vmem_addr_t)uma_zalloc(qc->qc_cache, flags); 1085 if (*addrp == 0) 1086 return (ENOMEM); 1087 return (0); 1088 } 1089 1090 return vmem_xalloc(vm, size, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, 1091 flags, addrp); 1092 } 1093 1094 int 1095 vmem_xalloc(vmem_t *vm, const vmem_size_t size0, vmem_size_t align, 1096 const vmem_size_t phase, const vmem_size_t nocross, 1097 const vmem_addr_t minaddr, const vmem_addr_t maxaddr, int flags, 1098 vmem_addr_t *addrp) 1099 { 1100 const vmem_size_t size = vmem_roundup_size(vm, size0); 1101 struct vmem_freelist *list; 1102 struct vmem_freelist *first; 1103 struct vmem_freelist *end; 1104 vmem_size_t avail; 1105 bt_t *bt; 1106 int error; 1107 int strat; 1108 1109 flags &= VMEM_FLAGS; 1110 strat = flags & VMEM_FITMASK; 1111 MPASS(size0 > 0); 1112 MPASS(size > 0); 1113 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT); 1114 MPASS((flags & (M_NOWAIT|M_WAITOK)) != (M_NOWAIT|M_WAITOK)); 1115 if ((flags & M_NOWAIT) == 0) 1116 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_xalloc"); 1117 MPASS((align & vm->vm_quantum_mask) == 0); 1118 MPASS((align & (align - 1)) == 0); 1119 MPASS((phase & vm->vm_quantum_mask) == 0); 1120 MPASS((nocross & vm->vm_quantum_mask) == 0); 1121 MPASS((nocross & (nocross - 1)) == 0); 1122 MPASS((align == 0 && phase == 0) || phase < align); 1123 MPASS(nocross == 0 || nocross >= size); 1124 MPASS(minaddr <= maxaddr); 1125 MPASS(!VMEM_CROSS_P(phase, phase + size - 1, nocross)); 1126 1127 if (align == 0) 1128 align = vm->vm_quantum_mask + 1; 1129 1130 *addrp = 0; 1131 end = &vm->vm_freelist[VMEM_MAXORDER]; 1132 /* 1133 * choose a free block from which we allocate. 1134 */ 1135 first = bt_freehead_toalloc(vm, size, strat); 1136 VMEM_LOCK(vm); 1137 for (;;) { 1138 /* 1139 * Make sure we have enough tags to complete the 1140 * operation. 1141 */ 1142 if (vm->vm_nfreetags < BT_MAXALLOC && 1143 bt_fill(vm, flags) != 0) { 1144 error = ENOMEM; 1145 break; 1146 } 1147 /* 1148 * Scan freelists looking for a tag that satisfies the 1149 * allocation. If we're doing BESTFIT we may encounter 1150 * sizes below the request. If we're doing FIRSTFIT we 1151 * inspect only the first element from each list. 1152 */ 1153 for (list = first; list < end; list++) { 1154 LIST_FOREACH(bt, list, bt_freelist) { 1155 if (bt->bt_size >= size) { 1156 error = vmem_fit(bt, size, align, phase, 1157 nocross, minaddr, maxaddr, addrp); 1158 if (error == 0) { 1159 vmem_clip(vm, bt, *addrp, size); 1160 goto out; 1161 } 1162 } 1163 /* FIRST skips to the next list. */ 1164 if (strat == M_FIRSTFIT) 1165 break; 1166 } 1167 } 1168 /* 1169 * Retry if the fast algorithm failed. 1170 */ 1171 if (strat == M_FIRSTFIT) { 1172 strat = M_BESTFIT; 1173 first = bt_freehead_toalloc(vm, size, strat); 1174 continue; 1175 } 1176 /* 1177 * XXX it is possible to fail to meet restrictions with the 1178 * imported region. It is up to the user to specify the 1179 * import quantum such that it can satisfy any allocation. 1180 */ 1181 if (vmem_import(vm, size, align, flags) == 0) 1182 continue; 1183 1184 /* 1185 * Try to free some space from the quantum cache or reclaim 1186 * functions if available. 1187 */ 1188 if (vm->vm_qcache_max != 0 || vm->vm_reclaimfn != NULL) { 1189 avail = vm->vm_size - vm->vm_inuse; 1190 VMEM_UNLOCK(vm); 1191 if (vm->vm_qcache_max != 0) 1192 qc_drain(vm); 1193 if (vm->vm_reclaimfn != NULL) 1194 vm->vm_reclaimfn(vm, flags); 1195 VMEM_LOCK(vm); 1196 /* If we were successful retry even NOWAIT. */ 1197 if (vm->vm_size - vm->vm_inuse > avail) 1198 continue; 1199 } 1200 if ((flags & M_NOWAIT) != 0) { 1201 error = ENOMEM; 1202 break; 1203 } 1204 VMEM_CONDVAR_WAIT(vm); 1205 } 1206 out: 1207 VMEM_UNLOCK(vm); 1208 if (error != 0 && (flags & M_NOWAIT) == 0) 1209 panic("failed to allocate waiting allocation\n"); 1210 1211 return (error); 1212 } 1213 1214 /* 1215 * vmem_free: free the resource to the arena. 1216 */ 1217 void 1218 vmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size) 1219 { 1220 qcache_t *qc; 1221 MPASS(size > 0); 1222 1223 if (size <= vm->vm_qcache_max) { 1224 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift]; 1225 uma_zfree(qc->qc_cache, (void *)addr); 1226 } else 1227 vmem_xfree(vm, addr, size); 1228 } 1229 1230 void 1231 vmem_xfree(vmem_t *vm, vmem_addr_t addr, vmem_size_t size) 1232 { 1233 bt_t *bt; 1234 bt_t *t; 1235 1236 MPASS(size > 0); 1237 1238 VMEM_LOCK(vm); 1239 bt = bt_lookupbusy(vm, addr); 1240 MPASS(bt != NULL); 1241 MPASS(bt->bt_start == addr); 1242 MPASS(bt->bt_size == vmem_roundup_size(vm, size) || 1243 bt->bt_size - vmem_roundup_size(vm, size) <= vm->vm_quantum_mask); 1244 MPASS(bt->bt_type == BT_TYPE_BUSY); 1245 bt_rembusy(vm, bt); 1246 bt->bt_type = BT_TYPE_FREE; 1247 1248 /* coalesce */ 1249 t = TAILQ_NEXT(bt, bt_seglist); 1250 if (t != NULL && t->bt_type == BT_TYPE_FREE) { 1251 MPASS(BT_END(bt) < t->bt_start); /* YYY */ 1252 bt->bt_size += t->bt_size; 1253 bt_remfree(vm, t); 1254 bt_remseg(vm, t); 1255 } 1256 t = TAILQ_PREV(bt, vmem_seglist, bt_seglist); 1257 if (t != NULL && t->bt_type == BT_TYPE_FREE) { 1258 MPASS(BT_END(t) < bt->bt_start); /* YYY */ 1259 bt->bt_size += t->bt_size; 1260 bt->bt_start = t->bt_start; 1261 bt_remfree(vm, t); 1262 bt_remseg(vm, t); 1263 } 1264 1265 t = TAILQ_PREV(bt, vmem_seglist, bt_seglist); 1266 MPASS(t != NULL); 1267 MPASS(BT_ISSPAN_P(t) || t->bt_type == BT_TYPE_BUSY); 1268 if (vm->vm_releasefn != NULL && t->bt_type == BT_TYPE_SPAN && 1269 t->bt_size == bt->bt_size) { 1270 vmem_addr_t spanaddr; 1271 vmem_size_t spansize; 1272 1273 MPASS(t->bt_start == bt->bt_start); 1274 spanaddr = bt->bt_start; 1275 spansize = bt->bt_size; 1276 bt_remseg(vm, bt); 1277 bt_remseg(vm, t); 1278 vm->vm_size -= spansize; 1279 VMEM_CONDVAR_BROADCAST(vm); 1280 bt_freetrim(vm, BT_MAXFREE); 1281 (*vm->vm_releasefn)(vm->vm_arg, spanaddr, spansize); 1282 } else { 1283 bt_insfree(vm, bt); 1284 VMEM_CONDVAR_BROADCAST(vm); 1285 bt_freetrim(vm, BT_MAXFREE); 1286 } 1287 } 1288 1289 /* 1290 * vmem_add: 1291 * 1292 */ 1293 int 1294 vmem_add(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int flags) 1295 { 1296 int error; 1297 1298 error = 0; 1299 flags &= VMEM_FLAGS; 1300 VMEM_LOCK(vm); 1301 if (vm->vm_nfreetags >= BT_MAXALLOC || bt_fill(vm, flags) == 0) 1302 vmem_add1(vm, addr, size, BT_TYPE_SPAN_STATIC); 1303 else 1304 error = ENOMEM; 1305 VMEM_UNLOCK(vm); 1306 1307 return (error); 1308 } 1309 1310 /* 1311 * vmem_size: information about arenas size 1312 */ 1313 vmem_size_t 1314 vmem_size(vmem_t *vm, int typemask) 1315 { 1316 1317 switch (typemask) { 1318 case VMEM_ALLOC: 1319 return vm->vm_inuse; 1320 case VMEM_FREE: 1321 return vm->vm_size - vm->vm_inuse; 1322 case VMEM_FREE|VMEM_ALLOC: 1323 return vm->vm_size; 1324 default: 1325 panic("vmem_size"); 1326 } 1327 } 1328 1329 /* ---- debug */ 1330 1331 #if defined(DDB) || defined(DIAGNOSTIC) 1332 1333 static void bt_dump(const bt_t *, int (*)(const char *, ...) 1334 __printflike(1, 2)); 1335 1336 static const char * 1337 bt_type_string(int type) 1338 { 1339 1340 switch (type) { 1341 case BT_TYPE_BUSY: 1342 return "busy"; 1343 case BT_TYPE_FREE: 1344 return "free"; 1345 case BT_TYPE_SPAN: 1346 return "span"; 1347 case BT_TYPE_SPAN_STATIC: 1348 return "static span"; 1349 default: 1350 break; 1351 } 1352 return "BOGUS"; 1353 } 1354 1355 static void 1356 bt_dump(const bt_t *bt, int (*pr)(const char *, ...)) 1357 { 1358 1359 (*pr)("\t%p: %jx %jx, %d(%s)\n", 1360 bt, (intmax_t)bt->bt_start, (intmax_t)bt->bt_size, 1361 bt->bt_type, bt_type_string(bt->bt_type)); 1362 } 1363 1364 static void 1365 vmem_dump(const vmem_t *vm , int (*pr)(const char *, ...) __printflike(1, 2)) 1366 { 1367 const bt_t *bt; 1368 int i; 1369 1370 (*pr)("vmem %p '%s'\n", vm, vm->vm_name); 1371 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { 1372 bt_dump(bt, pr); 1373 } 1374 1375 for (i = 0; i < VMEM_MAXORDER; i++) { 1376 const struct vmem_freelist *fl = &vm->vm_freelist[i]; 1377 1378 if (LIST_EMPTY(fl)) { 1379 continue; 1380 } 1381 1382 (*pr)("freelist[%d]\n", i); 1383 LIST_FOREACH(bt, fl, bt_freelist) { 1384 bt_dump(bt, pr); 1385 } 1386 } 1387 } 1388 1389 #endif /* defined(DDB) || defined(DIAGNOSTIC) */ 1390 1391 #if defined(DDB) 1392 static bt_t * 1393 vmem_whatis_lookup(vmem_t *vm, vmem_addr_t addr) 1394 { 1395 bt_t *bt; 1396 1397 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { 1398 if (BT_ISSPAN_P(bt)) { 1399 continue; 1400 } 1401 if (bt->bt_start <= addr && addr <= BT_END(bt)) { 1402 return bt; 1403 } 1404 } 1405 1406 return NULL; 1407 } 1408 1409 void 1410 vmem_whatis(vmem_addr_t addr, int (*pr)(const char *, ...)) 1411 { 1412 vmem_t *vm; 1413 1414 LIST_FOREACH(vm, &vmem_list, vm_alllist) { 1415 bt_t *bt; 1416 1417 bt = vmem_whatis_lookup(vm, addr); 1418 if (bt == NULL) { 1419 continue; 1420 } 1421 (*pr)("%p is %p+%zu in VMEM '%s' (%s)\n", 1422 (void *)addr, (void *)bt->bt_start, 1423 (vmem_size_t)(addr - bt->bt_start), vm->vm_name, 1424 (bt->bt_type == BT_TYPE_BUSY) ? "allocated" : "free"); 1425 } 1426 } 1427 1428 void 1429 vmem_printall(const char *modif, int (*pr)(const char *, ...)) 1430 { 1431 const vmem_t *vm; 1432 1433 LIST_FOREACH(vm, &vmem_list, vm_alllist) { 1434 vmem_dump(vm, pr); 1435 } 1436 } 1437 1438 void 1439 vmem_print(vmem_addr_t addr, const char *modif, int (*pr)(const char *, ...)) 1440 { 1441 const vmem_t *vm = (const void *)addr; 1442 1443 vmem_dump(vm, pr); 1444 } 1445 #endif /* defined(DDB) */ 1446 1447 #define vmem_printf printf 1448 1449 #if defined(DIAGNOSTIC) 1450 1451 static bool 1452 vmem_check_sanity(vmem_t *vm) 1453 { 1454 const bt_t *bt, *bt2; 1455 1456 MPASS(vm != NULL); 1457 1458 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { 1459 if (bt->bt_start > BT_END(bt)) { 1460 printf("corrupted tag\n"); 1461 bt_dump(bt, vmem_printf); 1462 return false; 1463 } 1464 } 1465 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { 1466 TAILQ_FOREACH(bt2, &vm->vm_seglist, bt_seglist) { 1467 if (bt == bt2) { 1468 continue; 1469 } 1470 if (BT_ISSPAN_P(bt) != BT_ISSPAN_P(bt2)) { 1471 continue; 1472 } 1473 if (bt->bt_start <= BT_END(bt2) && 1474 bt2->bt_start <= BT_END(bt)) { 1475 printf("overwrapped tags\n"); 1476 bt_dump(bt, vmem_printf); 1477 bt_dump(bt2, vmem_printf); 1478 return false; 1479 } 1480 } 1481 } 1482 1483 return true; 1484 } 1485 1486 static void 1487 vmem_check(vmem_t *vm) 1488 { 1489 1490 if (!vmem_check_sanity(vm)) { 1491 panic("insanity vmem %p", vm); 1492 } 1493 } 1494 1495 #endif /* defined(DIAGNOSTIC) */
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