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 if (vm_domainset_iter_policy_init(&di, ds, &domain, &flags) != 0) 327 return (NULL); 328 329 do { 330 addr = kmem_alloc_attr_domain(domain, size, flags, low, high, 331 memattr); 332 if (addr != NULL) 333 break; 334 if (start_segind == -1) 335 start_segind = vm_phys_lookup_segind(low); 336 if (vm_phys_find_range(bounds, start_segind, domain, 337 atop(round_page(size)), low, high) == -1) { 338 vm_domainset_iter_ignore(&di, domain); 339 } 340 } while (vm_domainset_iter_policy(&di, &domain) == 0); 341 342 return (addr); 343 } 344 345 /* 346 * Allocates a region from the kernel address map and physically 347 * contiguous pages within the specified address range to the kernel 348 * object. Creates a wired mapping from this region to these pages, and 349 * returns the region's starting virtual address. If M_ZERO is specified 350 * through the given flags, then the pages are zeroed before they are 351 * mapped. 352 */ 353 static void * 354 kmem_alloc_contig_domain(int domain, vm_size_t size, int flags, vm_paddr_t low, 355 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 356 vm_memattr_t memattr) 357 { 358 vmem_t *vmem; 359 vm_object_t object; 360 vm_offset_t addr, offset, tmp; 361 vm_page_t end_m, m; 362 vm_size_t asize; 363 u_long npages; 364 int pflags; 365 366 object = kernel_object; 367 asize = round_page(size); 368 vmem = vm_dom[domain].vmd_kernel_arena; 369 if (vmem_alloc(vmem, asize, flags | M_BESTFIT, &addr)) 370 return (NULL); 371 offset = addr - VM_MIN_KERNEL_ADDRESS; 372 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 373 npages = atop(asize); 374 VM_OBJECT_WLOCK(object); 375 m = kmem_alloc_contig_pages(object, atop(offset), domain, 376 pflags, npages, low, high, alignment, boundary, memattr); 377 if (m == NULL) { 378 VM_OBJECT_WUNLOCK(object); 379 vmem_free(vmem, addr, asize); 380 return (NULL); 381 } 382 KASSERT(vm_page_domain(m) == domain, 383 ("kmem_alloc_contig_domain: Domain mismatch %d != %d", 384 vm_page_domain(m), domain)); 385 end_m = m + npages; 386 tmp = addr; 387 for (; m < end_m; m++) { 388 if ((flags & M_ZERO) && (m->flags & PG_ZERO) == 0) 389 pmap_zero_page(m); 390 vm_page_valid(m); 391 pmap_enter(kernel_pmap, tmp, m, VM_PROT_RW, 392 VM_PROT_RW | PMAP_ENTER_WIRED, 0); 393 tmp += PAGE_SIZE; 394 } 395 VM_OBJECT_WUNLOCK(object); 396 kmem_alloc_san(addr, size, asize, flags); 397 return ((void *)addr); 398 } 399 400 void * 401 kmem_alloc_contig(vm_size_t size, int flags, vm_paddr_t low, vm_paddr_t high, 402 u_long alignment, vm_paddr_t boundary, vm_memattr_t memattr) 403 { 404 405 return (kmem_alloc_contig_domainset(DOMAINSET_RR(), size, flags, low, 406 high, alignment, boundary, memattr)); 407 } 408 409 void * 410 kmem_alloc_contig_domainset(struct domainset *ds, vm_size_t size, int flags, 411 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 412 vm_memattr_t memattr) 413 { 414 struct vm_domainset_iter di; 415 vm_page_t bounds[2]; 416 void *addr; 417 int domain; 418 int start_segind; 419 420 start_segind = -1; 421 422 if (vm_domainset_iter_policy_init(&di, ds, &domain, &flags)) 423 return (NULL); 424 425 do { 426 addr = kmem_alloc_contig_domain(domain, size, flags, low, high, 427 alignment, boundary, memattr); 428 if (addr != NULL) 429 break; 430 if (start_segind == -1) 431 start_segind = vm_phys_lookup_segind(low); 432 if (vm_phys_find_range(bounds, start_segind, domain, 433 atop(round_page(size)), low, high) == -1) { 434 vm_domainset_iter_ignore(&di, domain); 435 } 436 } while (vm_domainset_iter_policy(&di, &domain) == 0); 437 438 return (addr); 439 } 440 441 /* 442 * kmem_subinit: 443 * 444 * Initializes a map to manage a subrange 445 * of the kernel virtual address space. 446 * 447 * Arguments are as follows: 448 * 449 * parent Map to take range from 450 * min, max Returned endpoints of map 451 * size Size of range to find 452 * superpage_align Request that min is superpage aligned 453 */ 454 void 455 kmem_subinit(vm_map_t map, vm_map_t parent, vm_offset_t *min, vm_offset_t *max, 456 vm_size_t size, bool superpage_align) 457 { 458 int ret; 459 460 size = round_page(size); 461 462 *min = vm_map_min(parent); 463 ret = vm_map_find(parent, NULL, 0, min, size, 0, superpage_align ? 464 VMFS_SUPER_SPACE : VMFS_ANY_SPACE, VM_PROT_ALL, VM_PROT_ALL, 465 MAP_ACC_NO_CHARGE); 466 if (ret != KERN_SUCCESS) 467 panic("kmem_subinit: bad status return of %d", ret); 468 *max = *min + size; 469 vm_map_init(map, vm_map_pmap(parent), *min, *max); 470 if (vm_map_submap(parent, *min, *max, map) != KERN_SUCCESS) 471 panic("kmem_subinit: unable to change range to submap"); 472 } 473 474 /* 475 * kmem_malloc_domain: 476 * 477 * Allocate wired-down pages in the kernel's address space. 478 */ 479 static void * 480 kmem_malloc_domain(int domain, vm_size_t size, int flags) 481 { 482 vmem_t *arena; 483 vm_offset_t addr; 484 vm_size_t asize; 485 int rv; 486 487 if (__predict_true((flags & (M_EXEC | M_NEVERFREED)) == 0)) 488 arena = vm_dom[domain].vmd_kernel_arena; 489 else if ((flags & M_EXEC) != 0) 490 arena = vm_dom[domain].vmd_kernel_rwx_arena; 491 else 492 arena = vm_dom[domain].vmd_kernel_nofree_arena; 493 asize = round_page(size); 494 if (vmem_alloc(arena, asize, flags | M_BESTFIT, &addr)) 495 return (0); 496 497 rv = kmem_back_domain(domain, kernel_object, addr, asize, flags); 498 if (rv != KERN_SUCCESS) { 499 vmem_free(arena, addr, asize); 500 return (0); 501 } 502 kasan_mark((void *)addr, size, asize, KASAN_KMEM_REDZONE); 503 return ((void *)addr); 504 } 505 506 void * 507 kmem_malloc(vm_size_t size, int flags) 508 { 509 void * p; 510 511 TSENTER(); 512 p = kmem_malloc_domainset(DOMAINSET_RR(), size, flags); 513 TSEXIT(); 514 return (p); 515 } 516 517 void * 518 kmem_malloc_domainset(struct domainset *ds, vm_size_t size, int flags) 519 { 520 struct vm_domainset_iter di; 521 void *addr; 522 int domain; 523 524 if (vm_domainset_iter_policy_init(&di, ds, &domain, &flags) != 0) 525 return (NULL); 526 527 do { 528 addr = kmem_malloc_domain(domain, size, flags); 529 if (addr != NULL) 530 break; 531 } while (vm_domainset_iter_policy(&di, &domain) == 0); 532 533 return (addr); 534 } 535 536 /* 537 * kmem_back_domain: 538 * 539 * Allocate physical pages from the specified domain for the specified 540 * virtual address range. 541 */ 542 int 543 kmem_back_domain(int domain, vm_object_t object, vm_offset_t addr, 544 vm_size_t size, int flags) 545 { 546 struct pctrie_iter pages; 547 vm_offset_t offset, i; 548 vm_page_t m; 549 vm_prot_t prot; 550 int pflags; 551 552 KASSERT(object == kernel_object, 553 ("kmem_back_domain: only supports kernel object.")); 554 555 offset = addr - VM_MIN_KERNEL_ADDRESS; 556 pflags = malloc2vm_flags(flags) | VM_ALLOC_WIRED; 557 pflags &= ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 558 if (flags & M_WAITOK) 559 pflags |= VM_ALLOC_WAITFAIL; 560 prot = (flags & M_EXEC) != 0 ? VM_PROT_ALL : VM_PROT_RW; 561 562 i = 0; 563 vm_page_iter_init(&pages, object); 564 VM_OBJECT_WLOCK(object); 565 retry: 566 for (; i < size; i += PAGE_SIZE) { 567 m = vm_page_alloc_domain_iter(object, atop(offset + i), 568 domain, pflags, &pages); 569 570 /* 571 * Ran out of space, free everything up and return. Don't need 572 * to lock page queues here as we know that the pages we got 573 * aren't on any queues. 574 */ 575 if (m == NULL) { 576 if ((flags & M_NOWAIT) == 0) 577 goto retry; 578 VM_OBJECT_WUNLOCK(object); 579 kmem_unback(object, addr, i); 580 return (KERN_NO_SPACE); 581 } 582 KASSERT(vm_page_domain(m) == domain, 583 ("kmem_back_domain: Domain mismatch %d != %d", 584 vm_page_domain(m), domain)); 585 if (flags & M_ZERO && (m->flags & PG_ZERO) == 0) 586 pmap_zero_page(m); 587 KASSERT((m->oflags & VPO_UNMANAGED) != 0, 588 ("kmem_malloc: page %p is managed", m)); 589 vm_page_valid(m); 590 pmap_enter(kernel_pmap, addr + i, m, prot, 591 prot | PMAP_ENTER_WIRED, 0); 592 if (__predict_false((prot & VM_PROT_EXECUTE) != 0)) 593 m->oflags |= VPO_KMEM_EXEC; 594 } 595 VM_OBJECT_WUNLOCK(object); 596 kmem_alloc_san(addr, size, size, flags); 597 return (KERN_SUCCESS); 598 } 599 600 /* 601 * kmem_back: 602 * 603 * Allocate physical pages for the specified virtual address range. 604 */ 605 int 606 kmem_back(vm_object_t object, vm_offset_t addr, vm_size_t size, int flags) 607 { 608 vm_offset_t end, next, start; 609 int domain, rv; 610 611 KASSERT(object == kernel_object, 612 ("kmem_back: only supports kernel object.")); 613 614 for (start = addr, end = addr + size; addr < end; addr = next) { 615 /* 616 * We must ensure that pages backing a given large virtual page 617 * all come from the same physical domain. 618 */ 619 if (vm_ndomains > 1) { 620 domain = (addr >> KVA_QUANTUM_SHIFT) % vm_ndomains; 621 while (VM_DOMAIN_EMPTY(domain)) 622 domain++; 623 next = roundup2(addr + 1, KVA_QUANTUM); 624 if (next > end || next < start) 625 next = end; 626 } else { 627 domain = 0; 628 next = end; 629 } 630 rv = kmem_back_domain(domain, object, addr, next - addr, flags); 631 if (rv != KERN_SUCCESS) { 632 kmem_unback(object, start, addr - start); 633 break; 634 } 635 } 636 return (rv); 637 } 638 639 /* 640 * kmem_unback: 641 * 642 * Unmap and free the physical pages underlying the specified virtual 643 * address range. 644 * 645 * A physical page must exist within the specified object at each index 646 * that is being unmapped. 647 */ 648 static struct vmem * 649 _kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 650 { 651 struct pctrie_iter pages; 652 struct vmem *arena; 653 vm_page_t m; 654 vm_offset_t end, offset; 655 int domain; 656 657 KASSERT(object == kernel_object, 658 ("kmem_unback: only supports kernel object.")); 659 660 if (size == 0) 661 return (NULL); 662 pmap_remove(kernel_pmap, addr, addr + size); 663 offset = addr - VM_MIN_KERNEL_ADDRESS; 664 end = offset + size; 665 vm_page_iter_init(&pages, object); 666 VM_OBJECT_WLOCK(object); 667 m = vm_radix_iter_lookup(&pages, atop(offset)); 668 domain = vm_page_domain(m); 669 if (__predict_true((m->oflags & VPO_KMEM_EXEC) == 0)) 670 arena = vm_dom[domain].vmd_kernel_arena; 671 else 672 arena = vm_dom[domain].vmd_kernel_rwx_arena; 673 for (; offset < end; offset += PAGE_SIZE, 674 m = vm_radix_iter_lookup(&pages, atop(offset))) { 675 vm_page_xbusy_claim(m); 676 vm_page_unwire_noq(m); 677 vm_page_iter_free(&pages, m); 678 } 679 VM_OBJECT_WUNLOCK(object); 680 681 return (arena); 682 } 683 684 void 685 kmem_unback(vm_object_t object, vm_offset_t addr, vm_size_t size) 686 { 687 688 (void)_kmem_unback(object, addr, size); 689 } 690 691 /* 692 * kmem_free: 693 * 694 * Free memory allocated with kmem_malloc. The size must match the 695 * original allocation. 696 */ 697 void 698 kmem_free(void *addr, vm_size_t size) 699 { 700 struct vmem *arena; 701 702 size = round_page(size); 703 kasan_mark(addr, size, size, 0); 704 arena = _kmem_unback(kernel_object, (uintptr_t)addr, size); 705 if (arena != NULL) 706 vmem_free(arena, (uintptr_t)addr, size); 707 } 708 709 /* 710 * kmap_alloc_wait: 711 * 712 * Allocates pageable memory from a sub-map of the kernel. If the submap 713 * has no room, the caller sleeps waiting for more memory in the submap. 714 * 715 * This routine may block. 716 */ 717 vm_offset_t 718 kmap_alloc_wait(vm_map_t map, vm_size_t size) 719 { 720 vm_offset_t addr; 721 722 size = round_page(size); 723 if (!swap_reserve(size)) 724 return (0); 725 726 for (;;) { 727 /* 728 * To make this work for more than one map, use the map's lock 729 * to lock out sleepers/wakers. 730 */ 731 vm_map_lock(map); 732 addr = vm_map_findspace(map, vm_map_min(map), size); 733 if (addr + size <= vm_map_max(map)) 734 break; 735 /* no space now; see if we can ever get space */ 736 if (vm_map_max(map) - vm_map_min(map) < size) { 737 vm_map_unlock(map); 738 swap_release(size); 739 return (0); 740 } 741 vm_map_modflags(map, MAP_NEEDS_WAKEUP, 0); 742 vm_map_unlock_and_wait(map, 0); 743 } 744 vm_map_insert(map, NULL, 0, addr, addr + size, VM_PROT_RW, VM_PROT_RW, 745 MAP_ACC_CHARGED); 746 vm_map_unlock(map); 747 return (addr); 748 } 749 750 /* 751 * kmap_free_wakeup: 752 * 753 * Returns memory to a submap of the kernel, and wakes up any processes 754 * waiting for memory in that map. 755 */ 756 void 757 kmap_free_wakeup(vm_map_t map, vm_offset_t addr, vm_size_t size) 758 { 759 760 vm_map_lock(map); 761 (void) vm_map_delete(map, trunc_page(addr), round_page(addr + size)); 762 if ((map->flags & MAP_NEEDS_WAKEUP) != 0) { 763 vm_map_modflags(map, 0, MAP_NEEDS_WAKEUP); 764 vm_map_wakeup(map); 765 } 766 vm_map_unlock(map); 767 } 768 769 void 770 kmem_init_zero_region(void) 771 { 772 vm_offset_t addr, i; 773 vm_page_t m; 774 775 /* 776 * Map a single physical page of zeros to a larger virtual range. 777 * This requires less looping in places that want large amounts of 778 * zeros, while not using much more physical resources. 779 */ 780 addr = kva_alloc(ZERO_REGION_SIZE); 781 m = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_ZERO | 782 VM_ALLOC_NOFREE); 783 for (i = 0; i < ZERO_REGION_SIZE; i += PAGE_SIZE) 784 pmap_qenter(addr + i, &m, 1); 785 pmap_protect(kernel_pmap, addr, addr + ZERO_REGION_SIZE, VM_PROT_READ); 786 787 zero_region = (const void *)addr; 788 } 789 790 /* 791 * Import KVA from the kernel map into the kernel arena. 792 */ 793 static int 794 kva_import(void *unused, vmem_size_t size, int flags, vmem_addr_t *addrp) 795 { 796 vm_offset_t addr; 797 int result; 798 799 TSENTER(); 800 KASSERT((size % KVA_QUANTUM) == 0, 801 ("kva_import: Size %jd is not a multiple of %d", 802 (intmax_t)size, (int)KVA_QUANTUM)); 803 addr = vm_map_min(kernel_map); 804 result = vm_map_find(kernel_map, NULL, 0, &addr, size, 0, 805 VMFS_SUPER_SPACE, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 806 if (result != KERN_SUCCESS) { 807 TSEXIT(); 808 return (ENOMEM); 809 } 810 811 *addrp = addr; 812 813 TSEXIT(); 814 return (0); 815 } 816 817 /* 818 * Import KVA from a parent arena into a per-domain arena. Imports must be 819 * KVA_QUANTUM-aligned and a multiple of KVA_QUANTUM in size. 820 */ 821 static int 822 kva_import_domain(void *arena, vmem_size_t size, int flags, vmem_addr_t *addrp) 823 { 824 825 KASSERT((size % KVA_QUANTUM) == 0, 826 ("kva_import_domain: Size %jd is not a multiple of %d", 827 (intmax_t)size, (int)KVA_QUANTUM)); 828 return (vmem_xalloc(arena, size, KVA_QUANTUM, 0, 0, VMEM_ADDR_MIN, 829 VMEM_ADDR_MAX, flags, addrp)); 830 } 831 832 /* 833 * kmem_init: 834 * 835 * Create the kernel map; insert a mapping covering kernel text, 836 * data, bss, and all space allocated thus far (`boostrap' data). The 837 * new map will thus map the range between VM_MIN_KERNEL_ADDRESS and 838 * `start' as allocated, and the range between `start' and `end' as free. 839 * Create the kernel vmem arena and its per-domain children. 840 */ 841 void 842 kmem_init(vm_offset_t start, vm_offset_t end) 843 { 844 vm_size_t quantum; 845 int domain; 846 847 vm_map_init_system(kernel_map, kernel_pmap, VM_MIN_KERNEL_ADDRESS, end); 848 vm_map_lock(kernel_map); 849 /* N.B.: cannot use kgdb to debug, starting with this assignment ... */ 850 (void)vm_map_insert(kernel_map, NULL, 0, 851 #ifdef __amd64__ 852 KERNBASE, 853 #else 854 VM_MIN_KERNEL_ADDRESS, 855 #endif 856 start, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 857 /* ... and ending with the completion of the above `insert' */ 858 859 #ifdef __amd64__ 860 /* 861 * Mark KVA used for the page array as allocated. Other platforms 862 * that handle vm_page_array allocation can simply adjust virtual_avail 863 * instead. 864 */ 865 (void)vm_map_insert(kernel_map, NULL, 0, (vm_offset_t)vm_page_array, 866 (vm_offset_t)vm_page_array + round_2mpage(vm_page_array_size * 867 sizeof(struct vm_page)), 868 VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT); 869 #endif 870 vm_map_unlock(kernel_map); 871 872 /* 873 * Use a large import quantum on NUMA systems. This helps minimize 874 * interleaving of superpages, reducing internal fragmentation within 875 * the per-domain arenas. 876 */ 877 if (vm_ndomains > 1 && PMAP_HAS_DMAP) 878 quantum = KVA_NUMA_IMPORT_QUANTUM; 879 else 880 quantum = KVA_QUANTUM; 881 882 /* 883 * Initialize the kernel_arena. This can grow on demand. 884 */ 885 vmem_init(kernel_arena, "kernel arena", 0, 0, PAGE_SIZE, 0, 0); 886 vmem_set_import(kernel_arena, kva_import, NULL, NULL, quantum); 887 888 for (domain = 0; domain < vm_ndomains; domain++) { 889 /* 890 * Initialize the per-domain arenas. These are used to color 891 * the KVA space in a way that ensures that virtual large pages 892 * are backed by memory from the same physical domain, 893 * maximizing the potential for superpage promotion. 894 */ 895 vm_dom[domain].vmd_kernel_arena = vmem_create( 896 "kernel arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 897 vmem_set_import(vm_dom[domain].vmd_kernel_arena, 898 kva_import_domain, NULL, kernel_arena, quantum); 899 900 /* 901 * In architectures with superpages, maintain separate arenas 902 * for allocations with permissions that differ from the 903 * "standard" read/write permissions used for kernel memory 904 * and pages that are never released, so as not to inhibit 905 * superpage promotion. 906 * 907 * Use the base import quantum since these arenas are rarely 908 * used. 909 */ 910 #if VM_NRESERVLEVEL > 0 911 vm_dom[domain].vmd_kernel_rwx_arena = vmem_create( 912 "kernel rwx arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 913 vm_dom[domain].vmd_kernel_nofree_arena = vmem_create( 914 "kernel NOFREE arena domain", 0, 0, PAGE_SIZE, 0, M_WAITOK); 915 vmem_set_import(vm_dom[domain].vmd_kernel_rwx_arena, 916 kva_import_domain, (vmem_release_t *)vmem_xfree, 917 kernel_arena, KVA_QUANTUM); 918 vmem_set_import(vm_dom[domain].vmd_kernel_nofree_arena, 919 kva_import_domain, (vmem_release_t *)vmem_xfree, 920 kernel_arena, KVA_QUANTUM); 921 #else 922 vm_dom[domain].vmd_kernel_rwx_arena = 923 vm_dom[domain].vmd_kernel_arena; 924 vm_dom[domain].vmd_kernel_nofree_arena = 925 vm_dom[domain].vmd_kernel_arena; 926 #endif 927 } 928 929 /* 930 * This must be the very first call so that the virtual address 931 * space used for early allocations is properly marked used in 932 * the map. 933 */ 934 uma_startup2(); 935 } 936 937 /* 938 * kmem_bootstrap_free: 939 * 940 * Free pages backing preloaded data (e.g., kernel modules) to the 941 * system. Currently only supported on platforms that create a 942 * vm_phys segment for preloaded data. 943 */ 944 void 945 kmem_bootstrap_free(vm_offset_t start, vm_size_t size) 946 { 947 #if defined(__i386__) || defined(__amd64__) 948 struct vm_domain *vmd; 949 vm_offset_t end, va; 950 vm_paddr_t pa; 951 vm_page_t m; 952 953 end = trunc_page(start + size); 954 start = round_page(start); 955 956 #ifdef __amd64__ 957 /* 958 * Preloaded files do not have execute permissions by default on amd64. 959 * Restore the default permissions to ensure that the direct map alias 960 * is updated. 961 */ 962 pmap_change_prot(start, end - start, VM_PROT_RW); 963 #endif 964 for (va = start; va < end; va += PAGE_SIZE) { 965 pa = pmap_kextract(va); 966 m = PHYS_TO_VM_PAGE(pa); 967 968 vmd = vm_pagequeue_domain(m); 969 vm_domain_free_lock(vmd); 970 vm_phys_free_pages(m, m->pool, 0); 971 vm_domain_free_unlock(vmd); 972 973 vm_domain_freecnt_inc(vmd, 1); 974 vm_cnt.v_page_count++; 975 } 976 pmap_remove(kernel_pmap, start, end); 977 (void)vmem_add(kernel_arena, start, end - start, M_WAITOK); 978 #endif 979 } 980 981 #ifdef PMAP_WANT_ACTIVE_CPUS_NAIVE 982 void 983 pmap_active_cpus(pmap_t pmap, cpuset_t *res) 984 { 985 struct thread *td; 986 struct proc *p; 987 struct vmspace *vm; 988 int c; 989 990 CPU_ZERO(res); 991 CPU_FOREACH(c) { 992 td = cpuid_to_pcpu[c]->pc_curthread; 993 p = td->td_proc; 994 if (p == NULL) 995 continue; 996 vm = vmspace_acquire_ref(p); 997 if (vm == NULL) 998 continue; 999 if (pmap == vmspace_pmap(vm)) 1000 CPU_SET(c, res); 1001 vmspace_free(vm); 1002 } 1003 } 1004 #endif 1005 1006 /* 1007 * Allow userspace to directly trigger the VM drain routine for testing 1008 * purposes. 1009 */ 1010 static int 1011 debug_vm_lowmem(SYSCTL_HANDLER_ARGS) 1012 { 1013 int error, i; 1014 1015 i = 0; 1016 error = sysctl_handle_int(oidp, &i, 0, req); 1017 if (error != 0) 1018 return (error); 1019 if ((i & ~(VM_LOW_KMEM | VM_LOW_PAGES)) != 0) 1020 return (EINVAL); 1021 if (i != 0) 1022 EVENTHANDLER_INVOKE(vm_lowmem, i); 1023 return (0); 1024 } 1025 SYSCTL_PROC(_debug, OID_AUTO, vm_lowmem, 1026 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_vm_lowmem, "I", 1027 "set to trigger vm_lowmem event with given flags"); 1028 1029 static int 1030 debug_uma_reclaim(SYSCTL_HANDLER_ARGS) 1031 { 1032 int error, i; 1033 1034 i = 0; 1035 error = sysctl_handle_int(oidp, &i, 0, req); 1036 if (error != 0 || req->newptr == NULL) 1037 return (error); 1038 if (i != UMA_RECLAIM_TRIM && i != UMA_RECLAIM_DRAIN && 1039 i != UMA_RECLAIM_DRAIN_CPU) 1040 return (EINVAL); 1041 uma_reclaim(i); 1042 return (0); 1043 } 1044 SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim, 1045 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, debug_uma_reclaim, "I", 1046 "set to generate request to reclaim uma caches"); 1047 1048 static int 1049 debug_uma_reclaim_domain(SYSCTL_HANDLER_ARGS) 1050 { 1051 int domain, error, request; 1052 1053 request = 0; 1054 error = sysctl_handle_int(oidp, &request, 0, req); 1055 if (error != 0 || req->newptr == NULL) 1056 return (error); 1057 1058 domain = request >> 4; 1059 request &= 0xf; 1060 if (request != UMA_RECLAIM_TRIM && request != UMA_RECLAIM_DRAIN && 1061 request != UMA_RECLAIM_DRAIN_CPU) 1062 return (EINVAL); 1063 if (domain < 0 || domain >= vm_ndomains) 1064 return (EINVAL); 1065 uma_reclaim_domain(request, domain); 1066 return (0); 1067 } 1068 SYSCTL_PROC(_debug, OID_AUTO, uma_reclaim_domain, 1069 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, 0, 1070 debug_uma_reclaim_domain, "I", 1071 ""); 1072