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 99 struct vm_map kernel_map_store; 100 struct vm_map exec_map_store; 101 struct vm_map pipe_map_store; 102 103 const void *zero_region; 104 CTASSERT((ZERO_REGION_SIZE & PAGE_MASK) == 0); 105 106 /* NB: Used by kernel debuggers. */ 107 const u_long vm_maxuser_address = VM_MAXUSER_ADDRESS; 108 109 u_int exec_map_entry_size; 110 u_int exec_map_entries; 111 112 SYSCTL_ULONG(_vm, OID_AUTO, min_kernel_address, CTLFLAG_RD, 113 #if defined(__amd64__) 114 &kva_layout.km_low, 0, 115 #else 116 SYSCTL_NULL_ULONG_PTR, VM_MIN_KERNEL_ADDRESS, 117 #endif 118 "Min kernel address"); 119 120 SYSCTL_ULONG(_vm, OID_AUTO, max_kernel_address, CTLFLAG_RD, 121 #if defined(__arm__) 122 &vm_max_kernel_address, 0, 123 #elif defined(__amd64__) 124 &kva_layout.km_high, 0, 125 #else 126 SYSCTL_NULL_ULONG_PTR, VM_MAX_KERNEL_ADDRESS, 127 #endif 128 "Max kernel address"); 129 130 #if VM_NRESERVLEVEL > 1 131 #define KVA_QUANTUM_SHIFT (VM_LEVEL_1_ORDER + VM_LEVEL_0_ORDER + \ 132 PAGE_SHIFT) 133 #elif VM_NRESERVLEVEL > 0 134 #define KVA_QUANTUM_SHIFT (VM_LEVEL_0_ORDER + PAGE_SHIFT) 135 #else 136 /* On non-superpage architectures we want large import sizes. */ 137 #define KVA_QUANTUM_SHIFT (8 + PAGE_SHIFT) 138 #endif 139 #define KVA_QUANTUM (1ul << KVA_QUANTUM_SHIFT) 140 #define KVA_NUMA_IMPORT_QUANTUM (KVA_QUANTUM * 128) 141 142 extern void uma_startup2(void); 143 144 /* 145 * kva_alloc: 146 * 147 * Allocate a virtual address range with no underlying object and 148 * no initial mapping to physical memory. Any mapping from this 149 * range to physical memory must be explicitly created prior to 150 * its use, typically with pmap_qenter(). Any attempt to create 151 * a mapping on demand through vm_fault() will result in a panic. 152 */ 153 vm_offset_t 154 kva_alloc(vm_size_t size) 155 { 156 vm_offset_t addr; 157 158 TSENTER(); 159 size = round_page(size); 160 if (vmem_xalloc(kernel_arena, size, 0, 0, 0, VMEM_ADDR_MIN, 161 VMEM_ADDR_MAX, M_BESTFIT | M_NOWAIT, &addr)) 162 return (0); 163 TSEXIT(); 164 165 return (addr); 166 } 167 168 /* 169 * kva_alloc_aligned: 170 * 171 * Allocate a virtual address range as in kva_alloc where the base 172 * address is aligned to align. 173 */ 174 vm_offset_t 175 kva_alloc_aligned(vm_size_t size, vm_size_t align) 176 { 177 vm_offset_t addr; 178 179 TSENTER(); 180 size = round_page(size); 181 if (vmem_xalloc(kernel_arena, size, align, 0, 0, VMEM_ADDR_MIN, 182 VMEM_ADDR_MAX, M_BESTFIT | M_NOWAIT, &addr)) 183 return (0); 184 TSEXIT(); 185 186 return (addr); 187 } 188 189 /* 190 * kva_free: 191 * 192 * Release a region of kernel virtual memory allocated 193 * with kva_alloc, and return the physical pages 194 * associated with that region. 195 * 196 * This routine may not block on kernel maps. 197 */ 198 void 199 kva_free(vm_offset_t addr, vm_size_t size) 200 { 201 202 size = round_page(size); 203 vmem_xfree(kernel_arena, addr, size); 204 } 205 206 /* 207 * Update sanitizer shadow state to reflect a new allocation. Force inlining to 208 * help make KMSAN origin tracking more precise. 209 */ 210 static __always_inline void 211 kmem_alloc_san(vm_offset_t addr, vm_size_t size, vm_size_t asize, int flags) 212 { 213 if ((flags & M_ZERO) == 0) { 214 kmsan_mark((void *)addr, asize, KMSAN_STATE_UNINIT); 215 kmsan_orig((void *)addr, asize, KMSAN_TYPE_KMEM, 216 KMSAN_RET_ADDR); 217 } else { 218 kmsan_mark((void *)addr, asize, KMSAN_STATE_INITED); 219 } 220 kasan_mark((void *)addr, size, asize, KASAN_KMEM_REDZONE); 221 } 222 223 static vm_page_t 224 kmem_alloc_contig_pages(vm_object_t object, vm_pindex_t pindex, int domain, 225 int pflags, u_long npages, vm_paddr_t low, vm_paddr_t high, 226 u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) 227 { 228 vm_page_t m; 229 int tries; 230 bool wait, reclaim; 231 232 VM_OBJECT_ASSERT_WLOCKED(object); 233 234 wait = (pflags & VM_ALLOC_WAITOK) != 0; 235 reclaim = (pflags & VM_ALLOC_NORECLAIM) == 0; 236 pflags &= ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 237 pflags |= VM_ALLOC_NOWAIT; 238 for (tries = wait ? 3 : 1;; tries--) { 239 m = vm_page_alloc_contig_domain(object, pindex, domain, pflags, 240 npages, low, high, alignment, boundary, memattr); 241 if (m != NULL || tries == 0 || !reclaim) 242 break; 243 244 VM_OBJECT_WUNLOCK(object); 245 if (vm_page_reclaim_contig_domain(domain, pflags, npages, 246 low, high, alignment, boundary) == ENOMEM && wait) 247 vm_wait_domain(domain); 248 VM_OBJECT_WLOCK(object); 249 } 250 return (m); 251 } 252 253 /* 254 * Allocates a region from the kernel address map and physical pages 255 * within the specified address range to the kernel object. Creates a 256 * wired mapping from this region to these pages, and returns the 257 * region's starting virtual address. The allocated pages are not 258 * necessarily physically contiguous. If M_ZERO is specified through the 259 * given flags, then the pages are zeroed before they are mapped. 260 */ 261 static void * 262 kmem_alloc_attr_domain(int domain, vm_size_t size, int flags, vm_paddr_t low, 263 vm_paddr_t high, vm_memattr_t memattr) 264 { 265 vmem_t *vmem; 266 vm_object_t object; 267 vm_offset_t addr, i, offset; 268 vm_page_t m; 269 vm_size_t asize; 270 int pflags; 271 vm_prot_t prot; 272 273 object = kernel_object; 274 asize = round_page(size); 275 vmem = vm_dom[domain].vmd_kernel_arena; 276 if (vmem_alloc(vmem, asize, M_BESTFIT | flags, &addr)) 277 return (0); 278 offset = addr - VM_MIN_KERNEL_ADDRESS; 279 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 280 prot = (flags & M_EXEC) != 0 ? VM_PROT_ALL : VM_PROT_RW; 281 VM_OBJECT_WLOCK(object); 282 for (i = 0; i < asize; i += PAGE_SIZE) { 283 m = kmem_alloc_contig_pages(object, atop(offset + i), 284 domain, pflags, 1, low, high, PAGE_SIZE, 0, memattr); 285 if (m == NULL) { 286 VM_OBJECT_WUNLOCK(object); 287 kmem_unback(object, addr, i); 288 vmem_free(vmem, addr, asize); 289 return (0); 290 } 291 KASSERT(vm_page_domain(m) == domain, 292 ("kmem_alloc_attr_domain: Domain mismatch %d != %d", 293 vm_page_domain(m), domain)); 294 if ((flags & M_ZERO) && (m->flags & PG_ZERO) == 0) 295 pmap_zero_page(m); 296 vm_page_valid(m); 297 pmap_enter(kernel_pmap, addr + i, m, prot, 298 prot | PMAP_ENTER_WIRED, 0); 299 } 300 VM_OBJECT_WUNLOCK(object); 301 kmem_alloc_san(addr, size, asize, flags); 302 return ((void *)addr); 303 } 304 305 void * 306 kmem_alloc_attr(vm_size_t size, int flags, vm_paddr_t low, vm_paddr_t high, 307 vm_memattr_t memattr) 308 { 309 310 return (kmem_alloc_attr_domainset(DOMAINSET_RR(), size, flags, low, 311 high, memattr)); 312 } 313 314 void * 315 kmem_alloc_attr_domainset(struct domainset *ds, vm_size_t size, int flags, 316 vm_paddr_t low, vm_paddr_t high, vm_memattr_t memattr) 317 { 318 struct vm_domainset_iter di; 319 vm_page_t bounds[2]; 320 void *addr; 321 int domain; 322 int start_segind; 323 324 start_segind = -1; 325 326 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 327 do { 328 addr = kmem_alloc_attr_domain(domain, size, flags, low, high, 329 memattr); 330 if (addr != NULL) 331 break; 332 if (start_segind == -1) 333 start_segind = vm_phys_lookup_segind(low); 334 if (vm_phys_find_range(bounds, start_segind, domain, 335 atop(round_page(size)), low, high) == -1) { 336 vm_domainset_iter_ignore(&di, domain); 337 } 338 } while (vm_domainset_iter_policy(&di, &domain) == 0); 339 340 return (addr); 341 } 342 343 /* 344 * Allocates a region from the kernel address map and physically 345 * contiguous pages within the specified address range to the kernel 346 * object. Creates a wired mapping from this region to these pages, and 347 * returns the region's starting virtual address. If M_ZERO is specified 348 * through the given flags, then the pages are zeroed before they are 349 * mapped. 350 */ 351 static void * 352 kmem_alloc_contig_domain(int domain, vm_size_t size, int flags, vm_paddr_t low, 353 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 354 vm_memattr_t memattr) 355 { 356 vmem_t *vmem; 357 vm_object_t object; 358 vm_offset_t addr, offset, tmp; 359 vm_page_t end_m, m; 360 vm_size_t asize; 361 u_long npages; 362 int pflags; 363 364 object = kernel_object; 365 asize = round_page(size); 366 vmem = vm_dom[domain].vmd_kernel_arena; 367 if (vmem_alloc(vmem, asize, flags | M_BESTFIT, &addr)) 368 return (NULL); 369 offset = addr - VM_MIN_KERNEL_ADDRESS; 370 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 371 npages = atop(asize); 372 VM_OBJECT_WLOCK(object); 373 m = kmem_alloc_contig_pages(object, atop(offset), domain, 374 pflags, npages, low, high, alignment, boundary, memattr); 375 if (m == NULL) { 376 VM_OBJECT_WUNLOCK(object); 377 vmem_free(vmem, addr, asize); 378 return (NULL); 379 } 380 KASSERT(vm_page_domain(m) == domain, 381 ("kmem_alloc_contig_domain: Domain mismatch %d != %d", 382 vm_page_domain(m), domain)); 383 end_m = m + npages; 384 tmp = addr; 385 for (; m < end_m; m++) { 386 if ((flags & M_ZERO) && (m->flags & PG_ZERO) == 0) 387 pmap_zero_page(m); 388 vm_page_valid(m); 389 pmap_enter(kernel_pmap, tmp, m, VM_PROT_RW, 390 VM_PROT_RW | PMAP_ENTER_WIRED, 0); 391 tmp += PAGE_SIZE; 392 } 393 VM_OBJECT_WUNLOCK(object); 394 kmem_alloc_san(addr, size, asize, flags); 395 return ((void *)addr); 396 } 397 398 void * 399 kmem_alloc_contig(vm_size_t size, int flags, vm_paddr_t low, vm_paddr_t high, 400 u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) 401 { 402 403 return (kmem_alloc_contig_domainset(DOMAINSET_RR(), size, flags, low, 404 high, alignment, boundary, memattr)); 405 } 406 407 void * 408 kmem_alloc_contig_domainset(struct domainset *ds, vm_size_t size, int flags, 409 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 410 vm_memattr_t memattr) 411 { 412 struct vm_domainset_iter di; 413 vm_page_t bounds[2]; 414 void *addr; 415 int domain; 416 int start_segind; 417 418 start_segind = -1; 419 420 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 421 do { 422 addr = kmem_alloc_contig_domain(domain, size, flags, low, high, 423 alignment, boundary, memattr); 424 if (addr != NULL) 425 break; 426 if (start_segind == -1) 427 start_segind = vm_phys_lookup_segind(low); 428 if (vm_phys_find_range(bounds, start_segind, domain, 429 atop(round_page(size)), low, high) == -1) { 430 vm_domainset_iter_ignore(&di, domain); 431 } 432 } while (vm_domainset_iter_policy(&di, &domain) == 0); 433 434 return (addr); 435 } 436 437 /* 438 * kmem_subinit: 439 * 440 * Initializes a map to manage a subrange 441 * of the kernel virtual address space. 442 * 443 * Arguments are as follows: 444 * 445 * parent Map to take range from 446 * min, max Returned endpoints of map 447 * size Size of range to find 448 * superpage_align Request that min is superpage aligned 449 */ 450 void 451 kmem_subinit(vm_map_t map, vm_map_t parent, vm_offset_t *min, vm_offset_t *max, 452 vm_size_t size, bool superpage_align) 453 { 454 int ret; 455 456 size = round_page(size); 457 458 *min = vm_map_min(parent); 459 ret = vm_map_find(parent, NULL, 0, min, size, 0, superpage_align ? 460 VMFS_SUPER_SPACE : VMFS_ANY_SPACE, VM_PROT_ALL, VM_PROT_ALL, 461 MAP_ACC_NO_CHARGE); 462 if (ret != KERN_SUCCESS) 463 panic("kmem_subinit: bad status return of %d", ret); 464 *max = *min + size; 465 vm_map_init(map, vm_map_pmap(parent), *min, *max); 466 if (vm_map_submap(parent, *min, *max, map) != KERN_SUCCESS) 467 panic("kmem_subinit: unable to change range to submap"); 468 } 469 470 /* 471 * kmem_malloc_domain: 472 * 473 * Allocate wired-down pages in the kernel's address space. 474 */ 475 static void * 476 kmem_malloc_domain(int domain, vm_size_t size, int flags) 477 { 478 vmem_t *arena; 479 vm_offset_t addr; 480 vm_size_t asize; 481 int rv; 482 483 if (__predict_true((flags & (M_EXEC | M_NEVERFREED)) == 0)) 484 arena = vm_dom[domain].vmd_kernel_arena; 485 else if ((flags & M_EXEC) != 0) 486 arena = vm_dom[domain].vmd_kernel_rwx_arena; 487 else 488 arena = vm_dom[domain].vmd_kernel_nofree_arena; 489 asize = round_page(size); 490 if (vmem_alloc(arena, asize, flags | M_BESTFIT, &addr)) 491 return (0); 492 493 rv = kmem_back_domain(domain, kernel_object, addr, asize, flags); 494 if (rv != KERN_SUCCESS) { 495 vmem_free(arena, addr, asize); 496 return (0); 497 } 498 kasan_mark((void *)addr, size, asize, KASAN_KMEM_REDZONE); 499 return ((void *)addr); 500 } 501 502 void * 503 kmem_malloc(vm_size_t size, int flags) 504 { 505 void * p; 506 507 TSENTER(); 508 p = kmem_malloc_domainset(DOMAINSET_RR(), size, flags); 509 TSEXIT(); 510 return (p); 511 } 512 513 void * 514 kmem_malloc_domainset(struct domainset *ds, vm_size_t size, int flags) 515 { 516 struct vm_domainset_iter di; 517 void *addr; 518 int domain; 519 520 vm_domainset_iter_policy_init(&di, ds, &domain, &flags); 521 do { 522 addr = kmem_malloc_domain(domain, size, flags); 523 if (addr != NULL) 524 break; 525 } while (vm_domainset_iter_policy(&di, &domain) == 0); 526 527 return (addr); 528 } 529 530 /* 531 * kmem_back_domain: 532 * 533 * Allocate physical pages from the specified domain for the specified 534 * virtual address range. 535 */ 536 int 537 kmem_back_domain(int domain, vm_object_t object, vm_offset_t addr, 538 vm_size_t size, int flags) 539 { 540 struct pctrie_iter pages; 541 vm_offset_t offset, i; 542 vm_page_t m; 543 vm_prot_t prot; 544 int pflags; 545 546 KASSERT(object == kernel_object, 547 ("kmem_back_domain: only supports kernel object.")); 548 549 offset = addr - VM_MIN_KERNEL_ADDRESS; 550 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 551 pflags &= ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 552 if (flags & M_WAITOK) 553 pflags |= VM_ALLOC_WAITFAIL; 554 prot = (flags & M_EXEC) != 0 ? VM_PROT_ALL : VM_PROT_RW; 555 556 i = 0; 557 vm_page_iter_init(&pages, object); 558 VM_OBJECT_WLOCK(object); 559 retry: 560 for (; i < size; i += PAGE_SIZE) { 561 m = vm_page_alloc_domain_iter(object, atop(offset + i), 562 domain, pflags, &pages); 563 564 /* 565 * Ran out of space, free everything up and return. Don't need 566 * to lock page queues here as we know that the pages we got 567 * aren't on any queues. 568 */ 569 if (m == NULL) { 570 if ((flags & M_NOWAIT) == 0) 571 goto retry; 572 VM_OBJECT_WUNLOCK(object); 573 kmem_unback(object, addr, i); 574 return (KERN_NO_SPACE); 575 } 576 KASSERT(vm_page_domain(m) == domain, 577 ("kmem_back_domain: Domain mismatch %d != %d", 578 vm_page_domain(m), domain)); 579 if (flags & M_ZERO && (m->flags & PG_ZERO) == 0) 580 pmap_zero_page(m); 581 KASSERT((m->oflags & VPO_UNMANAGED) != 0, 582 ("kmem_malloc: page %p is managed", m)); 583 vm_page_valid(m); 584 pmap_enter(kernel_pmap, addr + i, m, prot, 585 prot | PMAP_ENTER_WIRED, 0); 586 if (__predict_false((prot & VM_PROT_EXECUTE) != 0)) 587 m->oflags |= VPO_KMEM_EXEC; 588 } 589 VM_OBJECT_WUNLOCK(object); 590 kmem_alloc_san(addr, size, size, flags); 591 return (KERN_SUCCESS); 592 } 593 594 /* 595 * kmem_back: 596 * 597 * Allocate physical pages for the specified virtual address range. 598 */ 599 int 600 kmem_back(vm_object_t object, vm_offset_t addr, vm_size_t size, int flags) 601 { 602 vm_offset_t end, next, start; 603 int domain, rv; 604 605 KASSERT(object == kernel_object, 606 ("kmem_back: only supports kernel object.")); 607 608 for (start = addr, end = addr + size; addr < end; addr = next) { 609 /* 610 * We must ensure that pages backing a given large virtual page 611 * all come from the same physical domain. 612 */ 613 if (vm_ndomains > 1) { 614 domain = (addr >> KVA_QUANTUM_SHIFT) % vm_ndomains; 615 while (VM_DOMAIN_EMPTY(domain)) 616 domain++; 617 next = roundup2(addr + 1, KVA_QUANTUM); 618 if (next > end || next < start) 619 next = end; 620 } else { 621 domain = 0; 622 next = end; 623 } 624 rv = kmem_back_domain(domain, object, addr, next - addr, flags); 625 if (rv != KERN_SUCCESS) { 626 kmem_unback(object, start, addr - start); 627 break; 628 } 629 } 630 return (rv); 631 } 632 633 /* 634 * kmem_unback: 635 * 636 * Unmap and free the physical pages underlying the specified virtual 637 * address range. 638 * 639 * A physical page must exist within the specified object at each index 640 * that is being unmapped. 641 */ 642 static struct vmem * 643 _kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 644 { 645 struct pctrie_iter pages; 646 struct vmem *arena; 647 vm_page_t m; 648 vm_offset_t end, offset; 649 int domain; 650 651 KASSERT(object == kernel_object, 652 ("kmem_unback: only supports kernel object.")); 653 654 if (size == 0) 655 return (NULL); 656 pmap_remove(kernel_pmap, addr, addr + size); 657 offset = addr - VM_MIN_KERNEL_ADDRESS; 658 end = offset + size; 659 vm_page_iter_init(&pages, object); 660 VM_OBJECT_WLOCK(object); 661 m = vm_radix_iter_lookup(&pages, atop(offset)); 662 domain = vm_page_domain(m); 663 if (__predict_true((m->oflags & VPO_KMEM_EXEC) == 0)) 664 arena = vm_dom[domain].vmd_kernel_arena; 665 else 666 arena = vm_dom[domain].vmd_kernel_rwx_arena; 667 for (; offset < end; offset += PAGE_SIZE, 668 m = vm_radix_iter_lookup(&pages, atop(offset))) { 669 vm_page_xbusy_claim(m); 670 vm_page_unwire_noq(m); 671 vm_page_iter_free(&pages, m); 672 } 673 VM_OBJECT_WUNLOCK(object); 674 675 return (arena); 676 } 677 678 void 679 kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 680 { 681 682 (void)_kmem_unback(object, addr, size); 683 } 684 685 /* 686 * kmem_free: 687 * 688 * Free memory allocated with kmem_malloc. The size must match the 689 * original allocation. 690 */ 691 void 692 kmem_free(void *addr, vm_size_t size) 693 { 694 struct vmem *arena; 695 696 size = round_page(size); 697 kasan_mark(addr, size, size, 0); 698 arena = _kmem_unback(kernel_object, (uintptr_t)addr, size); 699 if (arena != NULL) 700 vmem_free(arena, (uintptr_t)addr, size); 701 } 702 703 /* 704 * kmap_alloc_wait: 705 * 706 * Allocates pageable memory from a sub-map of the kernel. If the submap 707 * has no room, the caller sleeps waiting for more memory in the submap. 708 * 709 * This routine may block. 710 */ 711 vm_offset_t 712 kmap_alloc_wait(vm_map_t map, vm_size_t size) 713 { 714 vm_offset_t addr; 715 716 size = round_page(size); 717 if (!swap_reserve(size)) 718 return (0); 719 720 for (;;) { 721 /* 722 * To make this work for more than one map, use the map's lock 723 * to lock out sleepers/wakers. 724 */ 725 vm_map_lock(map); 726 addr = vm_map_findspace(map, vm_map_min(map), size); 727 if (addr + size <= vm_map_max(map)) 728 break; 729 /* no space now; see if we can ever get space */ 730 if (vm_map_max(map) - vm_map_min(map) < size) { 731 vm_map_unlock(map); 732 swap_release(size); 733 return (0); 734 } 735 vm_map_modflags(map, MAP_NEEDS_WAKEUP, 0); 736 vm_map_unlock_and_wait(map, 0); 737 } 738 vm_map_insert(map, NULL, 0, addr, addr + size, VM_PROT_RW, VM_PROT_RW, 739 MAP_ACC_CHARGED); 740 vm_map_unlock(map); 741 return (addr); 742 } 743 744 /* 745 * kmap_free_wakeup: 746 * 747 * Returns memory to a submap of the kernel, and wakes up any processes 748 * waiting for memory in that map. 749 */ 750 void 751 kmap_free_wakeup(vm_map_t map, vm_offset_t addr, vm_size_t size) 752 { 753 754 vm_map_lock(map); 755 (void) vm_map_delete(map, trunc_page(addr), round_page(addr + size)); 756 if ((map->flags & MAP_NEEDS_WAKEUP) != 0) { 757 vm_map_modflags(map, 0, MAP_NEEDS_WAKEUP); 758 vm_map_wakeup(map); 759 } 760 vm_map_unlock(map); 761 } 762 763 void 764 kmem_init_zero_region(void) 765 { 766 vm_offset_t addr, i; 767 vm_page_t m; 768 769 /* 770 * Map a single physical page of zeros to a larger virtual range. 771 * This requires less looping in places that want large amounts of 772 * zeros, while not using much more physical resources. 773 */ 774 addr = kva_alloc(ZERO_REGION_SIZE); 775 m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO | 776 VM_ALLOC_NOFREE); 777 for (i = 0; i < ZERO_REGION_SIZE; i += PAGE_SIZE) 778 pmap_qenter(addr + i, &m, 1); 779 pmap_protect(kernel_pmap, addr, addr + ZERO_REGION_SIZE, VM_PROT_READ); 780 781 zero_region = (const void *)addr; 782 } 783 784 /* 785 * Import KVA from the kernel map into the kernel arena. 786 */ 787 static int 788 kva_import(void *unused, vmem_size_t size, int flags, vmem_addr_t *addrp) 789 { 790 vm_offset_t addr; 791 int result; 792 793 TSENTER(); 794 KASSERT((size % KVA_QUANTUM) == 0, 795 ("kva_import: Size %jd is not a multiple of %d", 796 (intmax_t)size, (int)KVA_QUANTUM)); 797 addr = vm_map_min(kernel_map); 798 result = vm_map_find(kernel_map, NULL, 0, &addr, size, 0, 799 VMFS_SUPER_SPACE, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 800 if (result != KERN_SUCCESS) { 801 TSEXIT(); 802 return (ENOMEM); 803 } 804 805 *addrp = addr; 806 807 TSEXIT(); 808 return (0); 809 } 810 811 /* 812 * Import KVA from a parent arena into a per-domain arena. Imports must be 813 * KVA_QUANTUM-aligned and a multiple of KVA_QUANTUM in size. 814 */ 815 static int 816 kva_import_domain(void *arena, vmem_size_t size, int flags, vmem_addr_t *addrp) 817 { 818 819 KASSERT((size % KVA_QUANTUM) == 0, 820 ("kva_import_domain: Size %jd is not a multiple of %d", 821 (intmax_t)size, (int)KVA_QUANTUM)); 822 return (vmem_xalloc(arena, size, KVA_QUANTUM, 0, 0, VMEM_ADDR_MIN, 823 VMEM_ADDR_MAX, flags, addrp)); 824 } 825 826 /* 827 * kmem_init: 828 * 829 * Create the kernel map; insert a mapping covering kernel text, 830 * data, bss, and all space allocated thus far (`boostrap' data). The 831 * new map will thus map the range between VM_MIN_KERNEL_ADDRESS and 832 * `start' as allocated, and the range between `start' and `end' as free. 833 * Create the kernel vmem arena and its per-domain children. 834 */ 835 void 836 kmem_init(vm_offset_t start, vm_offset_t end) 837 { 838 vm_size_t quantum; 839 int domain; 840 841 vm_map_init_system(kernel_map, kernel_pmap, VM_MIN_KERNEL_ADDRESS, end); 842 vm_map_lock(kernel_map); 843 /* N.B.: cannot use kgdb to debug, starting with this assignment ... */ 844 (void)vm_map_insert(kernel_map, NULL, 0, 845 #ifdef __amd64__ 846 KERNBASE, 847 #else 848 VM_MIN_KERNEL_ADDRESS, 849 #endif 850 start, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 851 /* ... and ending with the completion of the above `insert' */ 852 853 #ifdef __amd64__ 854 /* 855 * Mark KVA used for the page array as allocated. Other platforms 856 * that handle vm_page_array allocation can simply adjust virtual_avail 857 * instead. 858 */ 859 (void)vm_map_insert(kernel_map, NULL, 0, (vm_offset_t)vm_page_array, 860 (vm_offset_t)vm_page_array + round_2mpage(vm_page_array_size * 861 sizeof(struct vm_page)), 862 VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT); 863 #endif 864 vm_map_unlock(kernel_map); 865 866 /* 867 * Use a large import quantum on NUMA systems. This helps minimize 868 * interleaving of superpages, reducing internal fragmentation within 869 * the per-domain arenas. 870 */ 871 if (vm_ndomains > 1 && PMAP_HAS_DMAP) 872 quantum = KVA_NUMA_IMPORT_QUANTUM; 873 else 874 quantum = KVA_QUANTUM; 875 876 /* 877 * Initialize the kernel_arena. This can grow on demand. 878 */ 879 vmem_init(kernel_arena, "kernel arena", 0, 0, PAGE_SIZE, 0, 0); 880 vmem_set_import(kernel_arena, kva_import, NULL, NULL, quantum); 881 882 for (domain = 0; domain < vm_ndomains; domain++) { 883 /* 884 * Initialize the per-domain arenas. These are used to color 885 * the KVA space in a way that ensures that virtual large pages 886 * are backed by memory from the same physical domain, 887 * maximizing the potential for superpage promotion. 888 */ 889 vm_dom[domain].vmd_kernel_arena = vmem_create( 890 "kernel arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 891 vmem_set_import(vm_dom[domain].vmd_kernel_arena, 892 kva_import_domain, NULL, kernel_arena, quantum); 893 894 /* 895 * In architectures with superpages, maintain separate arenas 896 * for allocations with permissions that differ from the 897 * "standard" read/write permissions used for kernel memory 898 * and pages that are never released, so as not to inhibit 899 * superpage promotion. 900 * 901 * Use the base import quantum since these arenas are rarely 902 * used. 903 */ 904 #if VM_NRESERVLEVEL > 0 905 vm_dom[domain].vmd_kernel_rwx_arena = vmem_create( 906 "kernel rwx arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 907 vm_dom[domain].vmd_kernel_nofree_arena = vmem_create( 908 "kernel NOFREE arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 909 vmem_set_import(vm_dom[domain].vmd_kernel_rwx_arena, 910 kva_import_domain, (vmem_release_t *)vmem_xfree, 911 kernel_arena, KVA_QUANTUM); 912 vmem_set_import(vm_dom[domain].vmd_kernel_nofree_arena, 913 kva_import_domain, (vmem_release_t *)vmem_xfree, 914 kernel_arena, KVA_QUANTUM); 915 #else 916 vm_dom[domain].vmd_kernel_rwx_arena = 917 vm_dom[domain].vmd_kernel_arena; 918 vm_dom[domain].vmd_kernel_nofree_arena = 919 vm_dom[domain].vmd_kernel_arena; 920 #endif 921 } 922 923 /* 924 * This must be the very first call so that the virtual address 925 * space used for early allocations is properly marked used in 926 * the map. 927 */ 928 uma_startup2(); 929 } 930 931 /* 932 * kmem_bootstrap_free: 933 * 934 * Free pages backing preloaded data (e.g., kernel modules) to the 935 * system. Currently only supported on platforms that create a 936 * vm_phys segment for preloaded data. 937 */ 938 void 939 kmem_bootstrap_free(vm_offset_t start, vm_size_t size) 940 { 941 #if defined(__i386__) || defined(__amd64__) 942 struct vm_domain *vmd; 943 vm_offset_t end, va; 944 vm_paddr_t pa; 945 vm_page_t m; 946 947 end = trunc_page(start + size); 948 start = round_page(start); 949 950 #ifdef __amd64__ 951 /* 952 * Preloaded files do not have execute permissions by default on amd64. 953 * Restore the default permissions to ensure that the direct map alias 954 * is updated. 955 */ 956 pmap_change_prot(start, end - start, VM_PROT_RW); 957 #endif 958 for (va = start; va < end; va += PAGE_SIZE) { 959 pa = pmap_kextract(va); 960 m = PHYS_TO_VM_PAGE(pa); 961 962 vmd = vm_pagequeue_domain(m); 963 vm_domain_free_lock(vmd); 964 vm_phys_free_pages(m, m->pool, 0); 965 vm_domain_free_unlock(vmd); 966 967 vm_domain_freecnt_inc(vmd, 1); 968 vm_cnt.v_page_count++; 969 } 970 pmap_remove(kernel_pmap, start, end); 971 (void)vmem_add(kernel_arena, start, end - start, M_WAITOK); 972 #endif 973 } 974 975 #ifdef PMAP_WANT_ACTIVE_CPUS_NAIVE 976 void 977 pmap_active_cpus(pmap_t pmap, cpuset_t *res) 978 { 979 struct thread *td; 980 struct proc *p; 981 struct vmspace *vm; 982 int c; 983 984 CPU_ZERO(res); 985 CPU_FOREACH(c) { 986 td = cpuid_to_pcpu[c]->pc_curthread; 987 p = td->td_proc; 988 if (p == NULL) 989 continue; 990 vm = vmspace_acquire_ref(p); 991 if (vm == NULL) 992 continue; 993 if (pmap == vmspace_pmap(vm)) 994 CPU_SET(c, res); 995 vmspace_free(vm); 996 } 997 } 998 #endif 999 1000 /* 1001 * Allow userspace to directly trigger the VM drain routine for testing 1002 * purposes. 1003 */ 1004 static int 1005 debug_vm_lowmem(SYSCTL_HANDLER_ARGS) 1006 { 1007 int error, i; 1008 1009 i = 0; 1010 error = sysctl_handle_int(oidp, &i, 0, req); 1011 if (error != 0) 1012 return (error); 1013 if ((i & ~(VM_LOW_KMEM | VM_LOW_PAGES)) != 0) 1014 return (EINVAL); 1015 if (i != 0) 1016 EVENTHANDLER_INVOKE(vm_lowmem, i); 1017 return (0); 1018 } 1019 SYSCTL_PROC(_debug, OID_AUTO, vm_lowmem, 1020 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_vm_lowmem, "I", 1021 "set to trigger vm_lowmem event with given flags"); 1022 1023 static int 1024 debug_uma_reclaim(SYSCTL_HANDLER_ARGS) 1025 { 1026 int error, i; 1027 1028 i = 0; 1029 error = sysctl_handle_int(oidp, &i, 0, req); 1030 if (error != 0 || req->newptr == NULL) 1031 return (error); 1032 if (i != UMA_RECLAIM_TRIM && i != UMA_RECLAIM_DRAIN && 1033 i != UMA_RECLAIM_DRAIN_CPU) 1034 return (EINVAL); 1035 uma_reclaim(i); 1036 return (0); 1037 } 1038 SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim, 1039 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_uma_reclaim, "I", 1040 "set to generate request to reclaim uma caches"); 1041 1042 static int 1043 debug_uma_reclaim_domain(SYSCTL_HANDLER_ARGS) 1044 { 1045 int domain, error, request; 1046 1047 request = 0; 1048 error = sysctl_handle_int(oidp, &request, 0, req); 1049 if (error != 0 || req->newptr == NULL) 1050 return (error); 1051 1052 domain = request >> 4; 1053 request &= 0xf; 1054 if (request != UMA_RECLAIM_TRIM && request != UMA_RECLAIM_DRAIN && 1055 request != UMA_RECLAIM_DRAIN_CPU) 1056 return (EINVAL); 1057 if (domain < 0 || domain >= vm_ndomains) 1058 return (EINVAL); 1059 uma_reclaim_domain(request, domain); 1060 return (0); 1061 } 1062 SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim_domain, 1063 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, 1064 debug_uma_reclaim_domain, "I", 1065 ""); 1066