1/*- 2 * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * The Mach Operating System project at Carnegie-Mellon University. 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 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * 35 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36 * All rights reserved. 37 * 38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39 * 40 * Permission to use, copy, modify and distribute this software and 41 * its documentation is hereby granted, provided that both the copyright 42 * notice and this permission notice appear in all copies of the 43 * software, derivative works or modified versions, and any portions 44 * thereof, and that both notices appear in supporting documentation. 45 * 46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49 * 50 * Carnegie Mellon requests users of this software to return to 51 * 52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53 * School of Computer Science 54 * Carnegie Mellon University 55 * Pittsburgh PA 15213-3890 56 * 57 * any improvements or extensions that they make and grant Carnegie the 58 * rights to redistribute these changes. 59 */ 60 61/* 62 * Kernel memory management. 63 */ 64 65#include <sys/cdefs.h> 66#include "opt_vm.h" 67 68#include <sys/param.h> 69#include <sys/systm.h> 70#include <sys/asan.h> 71#include <sys/domainset.h> 72#include <sys/eventhandler.h> 73#include <sys/kernel.h> 74#include <sys/lock.h> 75#include <sys/malloc.h> 76#include <sys/msan.h> 77#include <sys/proc.h> 78#include <sys/rwlock.h> 79#include <sys/smp.h> 80#include <sys/sysctl.h> 81#include <sys/vmem.h> 82#include <sys/vmmeter.h> 83 84#include <vm/vm.h> 85#include <vm/vm_param.h> 86#include <vm/vm_domainset.h> 87#include <vm/vm_kern.h> 88#include <vm/pmap.h> 89#include <vm/vm_map.h> 90#include <vm/vm_object.h> 91#include <vm/vm_page.h> 92#include <vm/vm_pageout.h> 93#include <vm/vm_pagequeue.h> 94#include <vm/vm_phys.h> 95#include <vm/vm_radix.h> 96#include <vm/vm_extern.h> 97#include <vm/uma.h> 98 99struct vm_map kernel_map_store; 100struct vm_map exec_map_store; 101struct vm_map pipe_map_store; 102 103const void *zero_region; 104CTASSERT((ZERO_REGION_SIZE & PAGE_MASK) == 0); 105 106/* NB: Used by kernel debuggers. */ 107const u_long vm_maxuser_address = VM_MAXUSER_ADDRESS; 108 109u_int exec_map_entry_size; 110u_int exec_map_entries; 111 112SYSCTL_ULONG(_vm, OID_AUTO, min_kernel_address, CTLFLAG_RD, 113 SYSCTL_NULL_ULONG_PTR, VM_MIN_KERNEL_ADDRESS, "Min kernel address"); 114 115SYSCTL_ULONG(_vm, OID_AUTO, max_kernel_address, CTLFLAG_RD, 116#if defined(__arm__) 117 &vm_max_kernel_address, 0, 118#else 119 SYSCTL_NULL_ULONG_PTR, VM_MAX_KERNEL_ADDRESS, 120#endif 121 "Max kernel address"); 122 123#if VM_NRESERVLEVEL > 0 124#define KVA_QUANTUM_SHIFT (VM_LEVEL_0_ORDER + PAGE_SHIFT) 125#else 126/* On non-superpage architectures we want large import sizes. */ 127#define KVA_QUANTUM_SHIFT (8 + PAGE_SHIFT) 128#endif 129#define KVA_QUANTUM (1ul << KVA_QUANTUM_SHIFT) 130#define KVA_NUMA_IMPORT_QUANTUM (KVA_QUANTUM * 128) 131 132extern void uma_startup2(void); 133 134/* 135 * kva_alloc: 136 * 137 * Allocate a virtual address range with no underlying object and 138 * no initial mapping to physical memory. Any mapping from this 139 * range to physical memory must be explicitly created prior to 140 * its use, typically with pmap_qenter(). Any attempt to create 141 * a mapping on demand through vm_fault() will result in a panic. 142 */ 143vm_offset_t 144kva_alloc(vm_size_t size) 145{ 146 vm_offset_t addr; 147 148 TSENTER(); 149 size = round_page(size); 150 if (vmem_xalloc(kernel_arena, size, 0, 0, 0, VMEM_ADDR_MIN, 151 VMEM_ADDR_MAX, M_BESTFIT | M_NOWAIT, &addr)) 152 return (0); 153 TSEXIT(); 154 155 return (addr); 156} 157 158/* 159 * kva_alloc_aligned: 160 * 161 * Allocate a virtual address range as in kva_alloc where the base 162 * address is aligned to align. 163 */ 164vm_offset_t 165kva_alloc_aligned(vm_size_t size, vm_size_t align) 166{ 167 vm_offset_t addr; 168 169 TSENTER(); 170 size = round_page(size); 171 if (vmem_xalloc(kernel_arena, size, align, 0, 0, VMEM_ADDR_MIN, 172 VMEM_ADDR_MAX, M_BESTFIT | M_NOWAIT, &addr)) 173 return (0); 174 TSEXIT(); 175 176 return (addr); 177} 178 179/* 180 * kva_free: 181 * 182 * Release a region of kernel virtual memory allocated 183 * with kva_alloc, and return the physical pages 184 * associated with that region. 185 * 186 * This routine may not block on kernel maps. 187 */ 188void 189kva_free(vm_offset_t addr, vm_size_t size) 190{ 191 192 size = round_page(size); 193 vmem_xfree(kernel_arena, addr, size); 194} 195 196/* 197 * Update sanitizer shadow state to reflect a new allocation. Force inlining to 198 * help make KMSAN origin tracking more precise. 199 */ 200static __always_inline void 201kmem_alloc_san(vm_offset_t addr, vm_size_t size, vm_size_t asize, int flags) 202{ 203 if ((flags & M_ZERO) == 0) { 204 kmsan_mark((void *)addr, asize, KMSAN_STATE_UNINIT); 205 kmsan_orig((void *)addr, asize, KMSAN_TYPE_KMEM, 206 KMSAN_RET_ADDR); 207 } else { 208 kmsan_mark((void *)addr, asize, KMSAN_STATE_INITED); 209 } 210 kasan_mark((void *)addr, size, asize, KASAN_KMEM_REDZONE); 211} 212 213static vm_page_t 214kmem_alloc_contig_pages(vm_object_t object, vm_pindex_t pindex, int domain, 215 int pflags, u_long npages, vm_paddr_t low, vm_paddr_t high, 216 u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) 217{ 218 vm_page_t m; 219 int tries; 220 bool wait, reclaim; 221 222 VM_OBJECT_ASSERT_WLOCKED(object); 223 224 wait = (pflags & VM_ALLOC_WAITOK) != 0; 225 reclaim = (pflags & VM_ALLOC_NORECLAIM) == 0; 226 pflags &= ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 227 pflags |= VM_ALLOC_NOWAIT; 228 for (tries = wait ? 3 : 1;; tries--) { 229 m = vm_page_alloc_contig_domain(object, pindex, domain, pflags, 230 npages, low, high, alignment, boundary, memattr); 231 if (m != NULL || tries == 0 || !reclaim) 232 break; 233 234 VM_OBJECT_WUNLOCK(object); 235 if (vm_page_reclaim_contig_domain(domain, pflags, npages, 236 low, high, alignment, boundary) == ENOMEM && wait) 237 vm_wait_domain(domain); 238 VM_OBJECT_WLOCK(object); 239 } 240 return (m); 241} 242 243/* 244 * Allocates a region from the kernel address map and physical pages 245 * within the specified address range to the kernel object. Creates a 246 * wired mapping from this region to these pages, and returns the 247 * region's starting virtual address. The allocated pages are not 248 * necessarily physically contiguous. If M_ZERO is specified through the 249 * given flags, then the pages are zeroed before they are mapped. 250 */ 251static void * 252kmem_alloc_attr_domain(int domain, vm_size_t size, int flags, vm_paddr_t low, 253 vm_paddr_t high, vm_memattr_t memattr) 254{ 255 vmem_t *vmem; 256 vm_object_t object; 257 vm_offset_t addr, i, offset; 258 vm_page_t m; 259 vm_size_t asize; 260 int pflags; 261 vm_prot_t prot; 262 263 object = kernel_object; 264 asize = round_page(size); 265 vmem = vm_dom[domain].vmd_kernel_arena; 266 if (vmem_alloc(vmem, asize, M_BESTFIT | flags, &addr)) 267 return (0); 268 offset = addr - VM_MIN_KERNEL_ADDRESS; 269 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 270 prot = (flags & M_EXEC) != 0 ? VM_PROT_ALL : VM_PROT_RW; 271 VM_OBJECT_WLOCK(object); 272 for (i = 0; i < asize; i += PAGE_SIZE) { 273 m = kmem_alloc_contig_pages(object, atop(offset + i), 274 domain, pflags, 1, low, high, PAGE_SIZE, 0, memattr); 275 if (m == NULL) { 276 VM_OBJECT_WUNLOCK(object); 277 kmem_unback(object, addr, i); 278 vmem_free(vmem, addr, asize); 279 return (0); 280 } 281 KASSERT(vm_page_domain(m) == domain, 282 ("kmem_alloc_attr_domain: Domain mismatch %d != %d", 283 vm_page_domain(m), domain)); 284 if ((flags & M_ZERO) && (m->flags & PG_ZERO) == 0) 285 pmap_zero_page(m); 286 vm_page_valid(m); 287 pmap_enter(kernel_pmap, addr + i, m, prot, 288 prot | PMAP_ENTER_WIRED, 0); 289 } 290 VM_OBJECT_WUNLOCK(object); 291 kmem_alloc_san(addr, size, asize, flags); 292 return ((void *)addr); 293} 294 295void * 296kmem_alloc_attr(vm_size_t size, int flags, vm_paddr_t low, vm_paddr_t high, 297 vm_memattr_t memattr) 298{ 299 300 return (kmem_alloc_attr_domainset(DOMAINSET_RR(), size, flags, low, 301 high, memattr)); 302} 303 304void * 305kmem_alloc_attr_domainset(struct domainset *ds, vm_size_t size, int flags, 306 vm_paddr_t low, vm_paddr_t high, vm_memattr_t memattr) 307{ 308 struct vm_domainset_iter di; 309 vm_page_t bounds[2]; 310 void *addr; 311 int domain; 312 int start_segind; 313 314 start_segind = -1; 315 316 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 317 do { 318 addr = kmem_alloc_attr_domain(domain, size, flags, low, high, 319 memattr); 320 if (addr != NULL) 321 break; 322 if (start_segind == -1) 323 start_segind = vm_phys_lookup_segind(low); 324 if (vm_phys_find_range(bounds, start_segind, domain, 325 atop(round_page(size)), low, high) == -1) { 326 vm_domainset_iter_ignore(&di, domain); 327 } 328 } while (vm_domainset_iter_policy(&di, &domain) == 0); 329 330 return (addr); 331} 332 333/* 334 * Allocates a region from the kernel address map and physically 335 * contiguous pages within the specified address range to the kernel 336 * object. Creates a wired mapping from this region to these pages, and 337 * returns the region's starting virtual address. If M_ZERO is specified 338 * through the given flags, then the pages are zeroed before they are 339 * mapped. 340 */ 341static void * 342kmem_alloc_contig_domain(int domain, vm_size_t size, int flags, vm_paddr_t low, 343 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 344 vm_memattr_t memattr) 345{ 346 vmem_t *vmem; 347 vm_object_t object; 348 vm_offset_t addr, offset, tmp; 349 vm_page_t end_m, m; 350 vm_size_t asize; 351 u_long npages; 352 int pflags; 353 354 object = kernel_object; 355 asize = round_page(size); 356 vmem = vm_dom[domain].vmd_kernel_arena; 357 if (vmem_alloc(vmem, asize, flags | M_BESTFIT, &addr)) 358 return (NULL); 359 offset = addr - VM_MIN_KERNEL_ADDRESS; 360 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 361 npages = atop(asize); 362 VM_OBJECT_WLOCK(object); 363 m = kmem_alloc_contig_pages(object, atop(offset), domain, 364 pflags, npages, low, high, alignment, boundary, memattr); 365 if (m == NULL) { 366 VM_OBJECT_WUNLOCK(object); 367 vmem_free(vmem, addr, asize); 368 return (NULL); 369 } 370 KASSERT(vm_page_domain(m) == domain, 371 ("kmem_alloc_contig_domain: Domain mismatch %d != %d", 372 vm_page_domain(m), domain)); 373 end_m = m + npages; 374 tmp = addr; 375 for (; m < end_m; m++) { 376 if ((flags & M_ZERO) && (m->flags & PG_ZERO) == 0) 377 pmap_zero_page(m); 378 vm_page_valid(m); 379 pmap_enter(kernel_pmap, tmp, m, VM_PROT_RW, 380 VM_PROT_RW | PMAP_ENTER_WIRED, 0); 381 tmp += PAGE_SIZE; 382 } 383 VM_OBJECT_WUNLOCK(object); 384 kmem_alloc_san(addr, size, asize, flags); 385 return ((void *)addr); 386} 387 388void * 389kmem_alloc_contig(vm_size_t size, int flags, vm_paddr_t low, vm_paddr_t high, 390 u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) 391{ 392 393 return (kmem_alloc_contig_domainset(DOMAINSET_RR(), size, flags, low, 394 high, alignment, boundary, memattr)); 395} 396 397void * 398kmem_alloc_contig_domainset(struct domainset *ds, vm_size_t size, int flags, 399 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 400 vm_memattr_t memattr) 401{ 402 struct vm_domainset_iter di; 403 vm_page_t bounds[2]; 404 void *addr; 405 int domain; 406 int start_segind; 407 408 start_segind = -1; 409 410 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 411 do { 412 addr = kmem_alloc_contig_domain(domain, size, flags, low, high, 413 alignment, boundary, memattr); 414 if (addr != NULL) 415 break; 416 if (start_segind == -1) 417 start_segind = vm_phys_lookup_segind(low); 418 if (vm_phys_find_range(bounds, start_segind, domain, 419 atop(round_page(size)), low, high) == -1) { 420 vm_domainset_iter_ignore(&di, domain); 421 } 422 } while (vm_domainset_iter_policy(&di, &domain) == 0); 423 424 return (addr); 425} 426 427/* 428 * kmem_subinit: 429 * 430 * Initializes a map to manage a subrange 431 * of the kernel virtual address space. 432 * 433 * Arguments are as follows: 434 * 435 * parent Map to take range from 436 * min, max Returned endpoints of map 437 * size Size of range to find 438 * superpage_align Request that min is superpage aligned 439 */ 440void 441kmem_subinit(vm_map_t map, vm_map_t parent, vm_offset_t *min, vm_offset_t *max, 442 vm_size_t size, bool superpage_align) 443{ 444 int ret; 445 446 size = round_page(size); 447 448 *min = vm_map_min(parent); 449 ret = vm_map_find(parent, NULL, 0, min, size, 0, superpage_align ? 450 VMFS_SUPER_SPACE : VMFS_ANY_SPACE, VM_PROT_ALL, VM_PROT_ALL, 451 MAP_ACC_NO_CHARGE); 452 if (ret != KERN_SUCCESS) 453 panic("kmem_subinit: bad status return of %d", ret); 454 *max = *min + size; 455 vm_map_init(map, vm_map_pmap(parent), *min, *max); 456 if (vm_map_submap(parent, *min, *max, map) != KERN_SUCCESS) 457 panic("kmem_subinit: unable to change range to submap"); 458} 459 460/* 461 * kmem_malloc_domain: 462 * 463 * Allocate wired-down pages in the kernel's address space. 464 */ 465static void * 466kmem_malloc_domain(int domain, vm_size_t size, int flags) 467{ 468 vmem_t *arena; 469 vm_offset_t addr; 470 vm_size_t asize; 471 int rv; 472 473 if (__predict_true((flags & M_EXEC) == 0)) 474 arena = vm_dom[domain].vmd_kernel_arena; 475 else 476 arena = vm_dom[domain].vmd_kernel_rwx_arena; 477 asize = round_page(size); 478 if (vmem_alloc(arena, asize, flags | M_BESTFIT, &addr)) 479 return (0); 480 481 rv = kmem_back_domain(domain, kernel_object, addr, asize, flags); 482 if (rv != KERN_SUCCESS) { 483 vmem_free(arena, addr, asize); 484 return (0); 485 } 486 kasan_mark((void *)addr, size, asize, KASAN_KMEM_REDZONE); 487 return ((void *)addr); 488} 489 490void * 491kmem_malloc(vm_size_t size, int flags) 492{ 493 void * p; 494 495 TSENTER(); 496 p = kmem_malloc_domainset(DOMAINSET_RR(), size, flags); 497 TSEXIT(); 498 return (p); 499} 500 501void * 502kmem_malloc_domainset(struct domainset *ds, vm_size_t size, int flags) 503{ 504 struct vm_domainset_iter di; 505 void *addr; 506 int domain; 507 508 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 509 do { 510 addr = kmem_malloc_domain(domain, size, flags); 511 if (addr != NULL) 512 break; 513 } while (vm_domainset_iter_policy(&di, &domain) == 0); 514 515 return (addr); 516} 517 518/* 519 * kmem_back_domain: 520 * 521 * Allocate physical pages from the specified domain for the specified 522 * virtual address range. 523 */ 524int 525kmem_back_domain(int domain, vm_object_t object, vm_offset_t addr, 526 vm_size_t size, int flags) 527{ 528 vm_offset_t offset, i; 529 vm_page_t m, mpred; 530 vm_prot_t prot; 531 int pflags; 532 533 KASSERT(object == kernel_object, 534 ("kmem_back_domain: only supports kernel object.")); 535 536 offset = addr - VM_MIN_KERNEL_ADDRESS; 537 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 538 pflags &= ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 539 if (flags & M_WAITOK) 540 pflags |= VM_ALLOC_WAITFAIL; 541 prot = (flags & M_EXEC) != 0 ? VM_PROT_ALL : VM_PROT_RW; 542 543 i = 0; 544 VM_OBJECT_WLOCK(object); 545retry: 546 mpred = vm_radix_lookup_le(&object->rtree, atop(offset + i)); 547 for (; i < size; i += PAGE_SIZE, mpred = m) { 548 m = vm_page_alloc_domain_after(object, atop(offset + i), 549 domain, pflags, mpred); 550 551 /* 552 * Ran out of space, free everything up and return. Don't need 553 * to lock page queues here as we know that the pages we got 554 * aren't on any queues. 555 */ 556 if (m == NULL) { 557 if ((flags & M_NOWAIT) == 0) 558 goto retry; 559 VM_OBJECT_WUNLOCK(object); 560 kmem_unback(object, addr, i); 561 return (KERN_NO_SPACE); 562 } 563 KASSERT(vm_page_domain(m) == domain, 564 ("kmem_back_domain: Domain mismatch %d != %d", 565 vm_page_domain(m), domain)); 566 if (flags & M_ZERO && (m->flags & PG_ZERO) == 0) 567 pmap_zero_page(m); 568 KASSERT((m->oflags & VPO_UNMANAGED) != 0, 569 ("kmem_malloc: page %p is managed", m)); 570 vm_page_valid(m); 571 pmap_enter(kernel_pmap, addr + i, m, prot, 572 prot | PMAP_ENTER_WIRED, 0); 573 if (__predict_false((prot & VM_PROT_EXECUTE) != 0)) 574 m->oflags |= VPO_KMEM_EXEC; 575 } 576 VM_OBJECT_WUNLOCK(object); 577 kmem_alloc_san(addr, size, size, flags); 578 return (KERN_SUCCESS); 579} 580 581/* 582 * kmem_back: 583 * 584 * Allocate physical pages for the specified virtual address range. 585 */ 586int 587kmem_back(vm_object_t object, vm_offset_t addr, vm_size_t size, int flags) 588{ 589 vm_offset_t end, next, start; 590 int domain, rv; 591 592 KASSERT(object == kernel_object, 593 ("kmem_back: only supports kernel object.")); 594 595 for (start = addr, end = addr + size; addr < end; addr = next) { 596 /* 597 * We must ensure that pages backing a given large virtual page 598 * all come from the same physical domain. 599 */ 600 if (vm_ndomains > 1) { 601 domain = (addr >> KVA_QUANTUM_SHIFT) % vm_ndomains; 602 while (VM_DOMAIN_EMPTY(domain)) 603 domain++; 604 next = roundup2(addr + 1, KVA_QUANTUM); 605 if (next > end || next < start) 606 next = end; 607 } else { 608 domain = 0; 609 next = end; 610 } 611 rv = kmem_back_domain(domain, object, addr, next - addr, flags); 612 if (rv != KERN_SUCCESS) { 613 kmem_unback(object, start, addr - start); 614 break; 615 } 616 } 617 return (rv); 618} 619 620/* 621 * kmem_unback: 622 * 623 * Unmap and free the physical pages underlying the specified virtual 624 * address range. 625 * 626 * A physical page must exist within the specified object at each index 627 * that is being unmapped. 628 */ 629static struct vmem * 630_kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 631{ 632 struct vmem *arena; 633 vm_page_t m, next; 634 vm_offset_t end, offset; 635 int domain; 636 637 KASSERT(object == kernel_object, 638 ("kmem_unback: only supports kernel object.")); 639 640 if (size == 0) 641 return (NULL); 642 pmap_remove(kernel_pmap, addr, addr + size); 643 offset = addr - VM_MIN_KERNEL_ADDRESS; 644 end = offset + size; 645 VM_OBJECT_WLOCK(object); 646 m = vm_page_lookup(object, atop(offset)); 647 domain = vm_page_domain(m); 648 if (__predict_true((m->oflags & VPO_KMEM_EXEC) == 0)) 649 arena = vm_dom[domain].vmd_kernel_arena; 650 else 651 arena = vm_dom[domain].vmd_kernel_rwx_arena; 652 for (; offset < end; offset += PAGE_SIZE, m = next) { 653 next = vm_page_next(m); 654 vm_page_xbusy_claim(m); 655 vm_page_unwire_noq(m); 656 vm_page_free(m); 657 } 658 VM_OBJECT_WUNLOCK(object); 659 660 return (arena); 661} 662 663void 664kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 665{ 666 667 (void)_kmem_unback(object, addr, size); 668} 669 670/* 671 * kmem_free: 672 * 673 * Free memory allocated with kmem_malloc. The size must match the 674 * original allocation. 675 */ 676void 677kmem_free(void *addr, vm_size_t size) 678{ 679 struct vmem *arena; 680 681 size = round_page(size); 682 kasan_mark(addr, size, size, 0); 683 arena = _kmem_unback(kernel_object, (uintptr_t)addr, size); 684 if (arena != NULL) 685 vmem_free(arena, (uintptr_t)addr, size); 686} 687 688/* 689 * kmap_alloc_wait: 690 * 691 * Allocates pageable memory from a sub-map of the kernel. If the submap 692 * has no room, the caller sleeps waiting for more memory in the submap. 693 * 694 * This routine may block. 695 */ 696vm_offset_t 697kmap_alloc_wait(vm_map_t map, vm_size_t size) 698{ 699 vm_offset_t addr; 700 701 size = round_page(size); 702 if (!swap_reserve(size)) 703 return (0); 704 705 for (;;) { 706 /* 707 * To make this work for more than one map, use the map's lock 708 * to lock out sleepers/wakers. 709 */ 710 vm_map_lock(map); 711 addr = vm_map_findspace(map, vm_map_min(map), size); 712 if (addr + size <= vm_map_max(map)) 713 break; 714 /* no space now; see if we can ever get space */ 715 if (vm_map_max(map) - vm_map_min(map) < size) { 716 vm_map_unlock(map); 717 swap_release(size); 718 return (0); 719 } 720 map->needs_wakeup = TRUE; 721 vm_map_unlock_and_wait(map, 0); 722 } 723 vm_map_insert(map, NULL, 0, addr, addr + size, VM_PROT_RW, VM_PROT_RW, 724 MAP_ACC_CHARGED); 725 vm_map_unlock(map); 726 return (addr); 727} 728 729/* 730 * kmap_free_wakeup: 731 * 732 * Returns memory to a submap of the kernel, and wakes up any processes 733 * waiting for memory in that map. 734 */ 735void 736kmap_free_wakeup(vm_map_t map, vm_offset_t addr, vm_size_t size) 737{ 738 739 vm_map_lock(map); 740 (void) vm_map_delete(map, trunc_page(addr), round_page(addr + size)); 741 if (map->needs_wakeup) { 742 map->needs_wakeup = FALSE; 743 vm_map_wakeup(map); 744 } 745 vm_map_unlock(map); 746} 747 748void 749kmem_init_zero_region(void) 750{ 751 vm_offset_t addr, i; 752 vm_page_t m; 753 754 /* 755 * Map a single physical page of zeros to a larger virtual range. 756 * This requires less looping in places that want large amounts of 757 * zeros, while not using much more physical resources. 758 */ 759 addr = kva_alloc(ZERO_REGION_SIZE); 760 m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO); 761 for (i = 0; i < ZERO_REGION_SIZE; i += PAGE_SIZE) 762 pmap_qenter(addr + i, &m, 1); 763 pmap_protect(kernel_pmap, addr, addr + ZERO_REGION_SIZE, VM_PROT_READ); 764 765 zero_region = (const void *)addr; 766} 767 768/* 769 * Import KVA from the kernel map into the kernel arena. 770 */ 771static int 772kva_import(void *unused, vmem_size_t size, int flags, vmem_addr_t *addrp) 773{ 774 vm_offset_t addr; 775 int result; 776 777 TSENTER(); 778 KASSERT((size % KVA_QUANTUM) == 0, 779 ("kva_import: Size %jd is not a multiple of %d", 780 (intmax_t)size, (int)KVA_QUANTUM)); 781 addr = vm_map_min(kernel_map); 782 result = vm_map_find(kernel_map, NULL, 0, &addr, size, 0, 783 VMFS_SUPER_SPACE, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 784 if (result != KERN_SUCCESS) { 785 TSEXIT(); 786 return (ENOMEM); 787 } 788 789 *addrp = addr; 790 791 TSEXIT(); 792 return (0); 793} 794 795/* 796 * Import KVA from a parent arena into a per-domain arena. Imports must be 797 * KVA_QUANTUM-aligned and a multiple of KVA_QUANTUM in size. 798 */ 799static int 800kva_import_domain(void *arena, vmem_size_t size, int flags, vmem_addr_t *addrp) 801{ 802 803 KASSERT((size % KVA_QUANTUM) == 0, 804 ("kva_import_domain: Size %jd is not a multiple of %d", 805 (intmax_t)size, (int)KVA_QUANTUM)); 806 return (vmem_xalloc(arena, size, KVA_QUANTUM, 0, 0, VMEM_ADDR_MIN, 807 VMEM_ADDR_MAX, flags, addrp)); 808} 809 810/* 811 * kmem_init: 812 * 813 * Create the kernel map; insert a mapping covering kernel text, 814 * data, bss, and all space allocated thus far (`boostrap' data). The 815 * new map will thus map the range between VM_MIN_KERNEL_ADDRESS and 816 * `start' as allocated, and the range between `start' and `end' as free. 817 * Create the kernel vmem arena and its per-domain children. 818 */ 819void 820kmem_init(vm_offset_t start, vm_offset_t end) 821{ 822 vm_size_t quantum; 823 int domain; 824 825 vm_map_init(kernel_map, kernel_pmap, VM_MIN_KERNEL_ADDRESS, end); 826 kernel_map->system_map = 1; 827 vm_map_lock(kernel_map); 828 /* N.B.: cannot use kgdb to debug, starting with this assignment ... */ 829 (void)vm_map_insert(kernel_map, NULL, 0, 830#ifdef __amd64__ 831 KERNBASE, 832#else 833 VM_MIN_KERNEL_ADDRESS, 834#endif 835 start, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 836 /* ... and ending with the completion of the above `insert' */ 837 838#ifdef __amd64__ 839 /* 840 * Mark KVA used for the page array as allocated. Other platforms 841 * that handle vm_page_array allocation can simply adjust virtual_avail 842 * instead. 843 */ 844 (void)vm_map_insert(kernel_map, NULL, 0, (vm_offset_t)vm_page_array, 845 (vm_offset_t)vm_page_array + round_2mpage(vm_page_array_size * 846 sizeof(struct vm_page)), 847 VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT); 848#endif 849 vm_map_unlock(kernel_map); 850 851 /* 852 * Use a large import quantum on NUMA systems. This helps minimize 853 * interleaving of superpages, reducing internal fragmentation within 854 * the per-domain arenas. 855 */ 856 if (vm_ndomains > 1 && PMAP_HAS_DMAP) 857 quantum = KVA_NUMA_IMPORT_QUANTUM; 858 else 859 quantum = KVA_QUANTUM; 860 861 /* 862 * Initialize the kernel_arena. This can grow on demand. 863 */ 864 vmem_init(kernel_arena, "kernel arena", 0, 0, PAGE_SIZE, 0, 0); 865 vmem_set_import(kernel_arena, kva_import, NULL, NULL, quantum); 866 867 for (domain = 0; domain < vm_ndomains; domain++) { 868 /* 869 * Initialize the per-domain arenas. These are used to color 870 * the KVA space in a way that ensures that virtual large pages 871 * are backed by memory from the same physical domain, 872 * maximizing the potential for superpage promotion. 873 */ 874 vm_dom[domain].vmd_kernel_arena = vmem_create( 875 "kernel arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 876 vmem_set_import(vm_dom[domain].vmd_kernel_arena, 877 kva_import_domain, NULL, kernel_arena, quantum); 878 879 /* 880 * In architectures with superpages, maintain separate arenas 881 * for allocations with permissions that differ from the 882 * "standard" read/write permissions used for kernel memory, 883 * so as not to inhibit superpage promotion. 884 * 885 * Use the base import quantum since this arena is rarely used. 886 */ 887#if VM_NRESERVLEVEL > 0 888 vm_dom[domain].vmd_kernel_rwx_arena = vmem_create( 889 "kernel rwx arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 890 vmem_set_import(vm_dom[domain].vmd_kernel_rwx_arena, 891 kva_import_domain, (vmem_release_t *)vmem_xfree, 892 kernel_arena, KVA_QUANTUM); 893#else 894 vm_dom[domain].vmd_kernel_rwx_arena = 895 vm_dom[domain].vmd_kernel_arena; 896#endif 897 } 898 899 /* 900 * This must be the very first call so that the virtual address 901 * space used for early allocations is properly marked used in 902 * the map. 903 */ 904 uma_startup2(); 905} 906 907/* 908 * kmem_bootstrap_free: 909 * 910 * Free pages backing preloaded data (e.g., kernel modules) to the 911 * system. Currently only supported on platforms that create a 912 * vm_phys segment for preloaded data. 913 */ 914void 915kmem_bootstrap_free(vm_offset_t start, vm_size_t size) 916{ 917#if defined(__i386__) || defined(__amd64__) 918 struct vm_domain *vmd; 919 vm_offset_t end, va; 920 vm_paddr_t pa; 921 vm_page_t m; 922 923 end = trunc_page(start + size); 924 start = round_page(start); 925 926#ifdef __amd64__ 927 /* 928 * Preloaded files do not have execute permissions by default on amd64. 929 * Restore the default permissions to ensure that the direct map alias 930 * is updated. 931 */ 932 pmap_change_prot(start, end - start, VM_PROT_RW); 933#endif 934 for (va = start; va < end; va += PAGE_SIZE) { 935 pa = pmap_kextract(va); 936 m = PHYS_TO_VM_PAGE(pa); 937 938 vmd = vm_pagequeue_domain(m); 939 vm_domain_free_lock(vmd); 940 vm_phys_free_pages(m, 0); 941 vm_domain_free_unlock(vmd); 942 943 vm_domain_freecnt_inc(vmd, 1); 944 vm_cnt.v_page_count++; 945 } 946 pmap_remove(kernel_pmap, start, end); 947 (void)vmem_add(kernel_arena, start, end - start, M_WAITOK); 948#endif 949} 950 951#ifdef PMAP_WANT_ACTIVE_CPUS_NAIVE 952void 953pmap_active_cpus(pmap_t pmap, cpuset_t *res) 954{ 955 struct thread *td; 956 struct proc *p; 957 struct vmspace *vm; 958 int c; 959 960 CPU_ZERO(res); 961 CPU_FOREACH(c) { 962 td = cpuid_to_pcpu[c]->pc_curthread; 963 p = td->td_proc; 964 if (p == NULL) 965 continue; 966 vm = vmspace_acquire_ref(p); 967 if (vm == NULL) 968 continue; 969 if (pmap == vmspace_pmap(vm)) 970 CPU_SET(c, res); 971 vmspace_free(vm); 972 } 973} 974#endif 975 976/* 977 * Allow userspace to directly trigger the VM drain routine for testing 978 * purposes. 979 */ 980static int 981debug_vm_lowmem(SYSCTL_HANDLER_ARGS) 982{ 983 int error, i; 984 985 i = 0; 986 error = sysctl_handle_int(oidp, &i, 0, req); 987 if (error != 0) 988 return (error); 989 if ((i & ~(VM_LOW_KMEM | VM_LOW_PAGES)) != 0) 990 return (EINVAL); 991 if (i != 0) 992 EVENTHANDLER_INVOKE(vm_lowmem, i); 993 return (0); 994} 995SYSCTL_PROC(_debug, OID_AUTO, vm_lowmem, 996 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_vm_lowmem, "I", 997 "set to trigger vm_lowmem event with given flags"); 998 999static int 1000debug_uma_reclaim(SYSCTL_HANDLER_ARGS) 1001{ 1002 int error, i; 1003 1004 i = 0; 1005 error = sysctl_handle_int(oidp, &i, 0, req); 1006 if (error != 0 || req->newptr == NULL) 1007 return (error); 1008 if (i != UMA_RECLAIM_TRIM && i != UMA_RECLAIM_DRAIN && 1009 i != UMA_RECLAIM_DRAIN_CPU) 1010 return (EINVAL); 1011 uma_reclaim(i); 1012 return (0); 1013} 1014SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim, 1015 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_uma_reclaim, "I", 1016 "set to generate request to reclaim uma caches"); 1017 1018static int 1019debug_uma_reclaim_domain(SYSCTL_HANDLER_ARGS) 1020{ 1021 int domain, error, request; 1022 1023 request = 0; 1024 error = sysctl_handle_int(oidp, &request, 0, req); 1025 if (error != 0 || req->newptr == NULL) 1026 return (error); 1027 1028 domain = request >> 4; 1029 request &= 0xf; 1030 if (request != UMA_RECLAIM_TRIM && request != UMA_RECLAIM_DRAIN && 1031 request != UMA_RECLAIM_DRAIN_CPU) 1032 return (EINVAL); 1033 if (domain < 0 || domain >= vm_ndomains) 1034 return (EINVAL); 1035 uma_reclaim_domain(request, domain); 1036 return (0); 1037} 1038SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim_domain, 1039 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, 1040 debug_uma_reclaim_domain, "I", 1041 ""); 1042