uvm_km.c revision 1.93.4.4
1 /* $NetBSD: uvm_km.c,v 1.93.4.4 2007/09/18 15:28:13 ad Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Charles D. Cranor and Washington University. 5 * Copyright (c) 1991, 1993, The Regents of the University of California. 6 * 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * The Mach Operating System project at Carnegie-Mellon University. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by Charles D. Cranor, 23 * Washington University, the University of California, Berkeley and 24 * its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * @(#)vm_kern.c 8.3 (Berkeley) 1/12/94 42 * from: Id: uvm_km.c,v 1.1.2.14 1998/02/06 05:19:27 chs Exp 43 * 44 * 45 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 46 * All rights reserved. 47 * 48 * Permission to use, copy, modify and distribute this software and 49 * its documentation is hereby granted, provided that both the copyright 50 * notice and this permission notice appear in all copies of the 51 * software, derivative works or modified versions, and any portions 52 * thereof, and that both notices appear in supporting documentation. 53 * 54 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 55 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 56 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 57 * 58 * Carnegie Mellon requests users of this software to return to 59 * 60 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 61 * School of Computer Science 62 * Carnegie Mellon University 63 * Pittsburgh PA 15213-3890 64 * 65 * any improvements or extensions that they make and grant Carnegie the 66 * rights to redistribute these changes. 67 */ 68 69 /* 70 * uvm_km.c: handle kernel memory allocation and management 71 */ 72 73 /* 74 * overview of kernel memory management: 75 * 76 * the kernel virtual address space is mapped by "kernel_map." kernel_map 77 * starts at VM_MIN_KERNEL_ADDRESS and goes to VM_MAX_KERNEL_ADDRESS. 78 * note that VM_MIN_KERNEL_ADDRESS is equal to vm_map_min(kernel_map). 79 * 80 * the kernel_map has several "submaps." submaps can only appear in 81 * the kernel_map (user processes can't use them). submaps "take over" 82 * the management of a sub-range of the kernel's address space. submaps 83 * are typically allocated at boot time and are never released. kernel 84 * virtual address space that is mapped by a submap is locked by the 85 * submap's lock -- not the kernel_map's lock. 86 * 87 * thus, the useful feature of submaps is that they allow us to break 88 * up the locking and protection of the kernel address space into smaller 89 * chunks. 90 * 91 * the vm system has several standard kernel submaps, including: 92 * kmem_map => contains only wired kernel memory for the kernel 93 * malloc. 94 * mb_map => memory for large mbufs, 95 * pager_map => used to map "buf" structures into kernel space 96 * exec_map => used during exec to handle exec args 97 * etc... 98 * 99 * the kernel allocates its private memory out of special uvm_objects whose 100 * reference count is set to UVM_OBJ_KERN (thus indicating that the objects 101 * are "special" and never die). all kernel objects should be thought of 102 * as large, fixed-sized, sparsely populated uvm_objects. each kernel 103 * object is equal to the size of kernel virtual address space (i.e. the 104 * value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS"). 105 * 106 * note that just because a kernel object spans the entire kernel virutal 107 * address space doesn't mean that it has to be mapped into the entire space. 108 * large chunks of a kernel object's space go unused either because 109 * that area of kernel VM is unmapped, or there is some other type of 110 * object mapped into that range (e.g. a vnode). for submap's kernel 111 * objects, the only part of the object that can ever be populated is the 112 * offsets that are managed by the submap. 113 * 114 * note that the "offset" in a kernel object is always the kernel virtual 115 * address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)). 116 * example: 117 * suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a 118 * uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the 119 * kernel map]. if uvm_km_alloc returns virtual address 0xf8235000, 120 * then that means that the page at offset 0x235000 in kernel_object is 121 * mapped at 0xf8235000. 122 * 123 * kernel object have one other special property: when the kernel virtual 124 * memory mapping them is unmapped, the backing memory in the object is 125 * freed right away. this is done with the uvm_km_pgremove() function. 126 * this has to be done because there is no backing store for kernel pages 127 * and no need to save them after they are no longer referenced. 128 */ 129 130 #include <sys/cdefs.h> 131 __KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.93.4.4 2007/09/18 15:28:13 ad Exp $"); 132 133 #include "opt_uvmhist.h" 134 135 #include <sys/param.h> 136 #include <sys/malloc.h> 137 #include <sys/systm.h> 138 #include <sys/proc.h> 139 #include <sys/pool.h> 140 141 #include <uvm/uvm.h> 142 143 /* 144 * global data structures 145 */ 146 147 struct vm_map *kernel_map = NULL; 148 149 /* 150 * local data structues 151 */ 152 153 static struct vm_map_kernel kernel_map_store; 154 static struct vm_map_entry kernel_first_mapent_store; 155 156 #if !defined(PMAP_MAP_POOLPAGE) 157 158 /* 159 * kva cache 160 * 161 * XXX maybe it's better to do this at the uvm_map layer. 162 */ 163 164 #define KM_VACACHE_SIZE (32 * PAGE_SIZE) /* XXX tune */ 165 166 static void *km_vacache_alloc(struct pool *, int); 167 static void km_vacache_free(struct pool *, void *); 168 static void km_vacache_init(struct vm_map *, const char *, size_t); 169 170 /* XXX */ 171 #define KM_VACACHE_POOL_TO_MAP(pp) \ 172 ((struct vm_map *)((char *)(pp) - \ 173 offsetof(struct vm_map_kernel, vmk_vacache))) 174 175 static void * 176 km_vacache_alloc(struct pool *pp, int flags) 177 { 178 vaddr_t va; 179 size_t size; 180 struct vm_map *map; 181 size = pp->pr_alloc->pa_pagesz; 182 183 map = KM_VACACHE_POOL_TO_MAP(pp); 184 185 va = vm_map_min(map); /* hint */ 186 if (uvm_map(map, &va, size, NULL, UVM_UNKNOWN_OFFSET, size, 187 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 188 UVM_ADV_RANDOM, UVM_FLAG_QUANTUM | 189 ((flags & PR_WAITOK) ? UVM_FLAG_WAITVA : UVM_FLAG_NOWAIT)))) 190 return NULL; 191 192 return (void *)va; 193 } 194 195 static void 196 km_vacache_free(struct pool *pp, void *v) 197 { 198 vaddr_t va = (vaddr_t)v; 199 size_t size = pp->pr_alloc->pa_pagesz; 200 struct vm_map *map; 201 202 map = KM_VACACHE_POOL_TO_MAP(pp); 203 uvm_unmap1(map, va, va + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 204 } 205 206 /* 207 * km_vacache_init: initialize kva cache. 208 */ 209 210 static void 211 km_vacache_init(struct vm_map *map, const char *name, size_t size) 212 { 213 struct vm_map_kernel *vmk; 214 struct pool *pp; 215 struct pool_allocator *pa; 216 int ipl; 217 218 KASSERT(VM_MAP_IS_KERNEL(map)); 219 KASSERT(size < (vm_map_max(map) - vm_map_min(map)) / 2); /* sanity */ 220 221 222 vmk = vm_map_to_kernel(map); 223 pp = &vmk->vmk_vacache; 224 pa = &vmk->vmk_vacache_allocator; 225 memset(pa, 0, sizeof(*pa)); 226 pa->pa_alloc = km_vacache_alloc; 227 pa->pa_free = km_vacache_free; 228 pa->pa_pagesz = (unsigned int)size; 229 pa->pa_backingmap = map; 230 pa->pa_backingmapptr = NULL; 231 232 if ((map->flags & VM_MAP_INTRSAFE) != 0) 233 ipl = IPL_VM; 234 else 235 ipl = IPL_NONE; 236 237 pool_init(pp, PAGE_SIZE, 0, 0, PR_NOTOUCH | PR_RECURSIVE, name, pa, 238 ipl); 239 } 240 241 void 242 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 243 { 244 245 map->flags |= VM_MAP_VACACHE; 246 if (size == 0) 247 size = KM_VACACHE_SIZE; 248 km_vacache_init(map, name, size); 249 } 250 251 #else /* !defined(PMAP_MAP_POOLPAGE) */ 252 253 void 254 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 255 { 256 257 /* nothing */ 258 } 259 260 #endif /* !defined(PMAP_MAP_POOLPAGE) */ 261 262 void 263 uvm_km_va_drain(struct vm_map *map, uvm_flag_t flags) 264 { 265 struct vm_map_kernel *vmk = vm_map_to_kernel(map); 266 267 callback_run_roundrobin(&vmk->vmk_reclaim_callback, NULL); 268 } 269 270 /* 271 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 272 * KVM already allocated for text, data, bss, and static data structures). 273 * 274 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 275 * we assume that [vmin -> start] has already been allocated and that 276 * "end" is the end. 277 */ 278 279 void 280 uvm_km_init(vaddr_t start, vaddr_t end) 281 { 282 vaddr_t base = VM_MIN_KERNEL_ADDRESS; 283 284 /* 285 * next, init kernel memory objects. 286 */ 287 288 /* kernel_object: for pageable anonymous kernel memory */ 289 uao_init(); 290 uvm_kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 291 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 292 293 /* 294 * init the map and reserve any space that might already 295 * have been allocated kernel space before installing. 296 */ 297 298 uvm_map_setup_kernel(&kernel_map_store, base, end, VM_MAP_PAGEABLE); 299 kernel_map_store.vmk_map.pmap = pmap_kernel(); 300 if (start != base) { 301 int error; 302 struct uvm_map_args args; 303 304 error = uvm_map_prepare(&kernel_map_store.vmk_map, 305 base, start - base, 306 NULL, UVM_UNKNOWN_OFFSET, 0, 307 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 308 UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args); 309 if (!error) { 310 kernel_first_mapent_store.flags = 311 UVM_MAP_KERNEL | UVM_MAP_FIRST; 312 error = uvm_map_enter(&kernel_map_store.vmk_map, &args, 313 &kernel_first_mapent_store); 314 } 315 316 if (error) 317 panic( 318 "uvm_km_init: could not reserve space for kernel"); 319 } 320 321 /* 322 * install! 323 */ 324 325 kernel_map = &kernel_map_store.vmk_map; 326 uvm_km_vacache_init(kernel_map, "kvakernel", 0); 327 } 328 329 /* 330 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 331 * is allocated all references to that area of VM must go through it. this 332 * allows the locking of VAs in kernel_map to be broken up into regions. 333 * 334 * => if `fixed' is true, *vmin specifies where the region described 335 * by the submap must start 336 * => if submap is non NULL we use that as the submap, otherwise we 337 * alloc a new map 338 */ 339 340 struct vm_map * 341 uvm_km_suballoc(struct vm_map *map, vaddr_t *vmin /* IN/OUT */, 342 vaddr_t *vmax /* OUT */, vsize_t size, int flags, bool fixed, 343 struct vm_map_kernel *submap) 344 { 345 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 346 347 KASSERT(vm_map_pmap(map) == pmap_kernel()); 348 349 size = round_page(size); /* round up to pagesize */ 350 size += uvm_mapent_overhead(size, flags); 351 352 /* 353 * first allocate a blank spot in the parent map 354 */ 355 356 if (uvm_map(map, vmin, size, NULL, UVM_UNKNOWN_OFFSET, 0, 357 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 358 UVM_ADV_RANDOM, mapflags)) != 0) { 359 panic("uvm_km_suballoc: unable to allocate space in parent map"); 360 } 361 362 /* 363 * set VM bounds (vmin is filled in by uvm_map) 364 */ 365 366 *vmax = *vmin + size; 367 368 /* 369 * add references to pmap and create or init the submap 370 */ 371 372 pmap_reference(vm_map_pmap(map)); 373 if (submap == NULL) { 374 submap = malloc(sizeof(*submap), M_VMMAP, M_WAITOK); 375 if (submap == NULL) 376 panic("uvm_km_suballoc: unable to create submap"); 377 } 378 uvm_map_setup_kernel(submap, *vmin, *vmax, flags); 379 submap->vmk_map.pmap = vm_map_pmap(map); 380 381 /* 382 * now let uvm_map_submap plug in it... 383 */ 384 385 if (uvm_map_submap(map, *vmin, *vmax, &submap->vmk_map) != 0) 386 panic("uvm_km_suballoc: submap allocation failed"); 387 388 return(&submap->vmk_map); 389 } 390 391 /* 392 * uvm_km_pgremove: remove pages from a kernel uvm_object. 393 * 394 * => when you unmap a part of anonymous kernel memory you want to toss 395 * the pages right away. (this gets called from uvm_unmap_...). 396 */ 397 398 void 399 uvm_km_pgremove(vaddr_t startva, vaddr_t endva) 400 { 401 struct uvm_object * const uobj = uvm_kernel_object; 402 const voff_t start = startva - vm_map_min(kernel_map); 403 const voff_t end = endva - vm_map_min(kernel_map); 404 struct vm_page *pg; 405 voff_t curoff, nextoff; 406 int swpgonlydelta = 0; 407 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 408 409 KASSERT(VM_MIN_KERNEL_ADDRESS <= startva); 410 KASSERT(startva < endva); 411 KASSERT(endva <= VM_MAX_KERNEL_ADDRESS); 412 413 mutex_enter(&uobj->vmobjlock); 414 415 for (curoff = start; curoff < end; curoff = nextoff) { 416 nextoff = curoff + PAGE_SIZE; 417 pg = uvm_pagelookup(uobj, curoff); 418 if (pg != NULL && pg->flags & PG_BUSY) { 419 pg->flags |= PG_WANTED; 420 UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, 421 "km_pgrm", 0); 422 mutex_enter(&uobj->vmobjlock); 423 nextoff = curoff; 424 continue; 425 } 426 427 /* 428 * free the swap slot, then the page. 429 */ 430 431 if (pg == NULL && 432 uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) { 433 swpgonlydelta++; 434 } 435 uao_dropswap(uobj, curoff >> PAGE_SHIFT); 436 if (pg != NULL) { 437 mutex_enter(&uvm_pageqlock); 438 uvm_pagefree(pg); 439 mutex_exit(&uvm_pageqlock); 440 } 441 } 442 mutex_exit(&uobj->vmobjlock); 443 444 if (swpgonlydelta > 0) { 445 mutex_enter(&uvm_swap_data_lock); 446 KASSERT(uvmexp.swpgonly >= swpgonlydelta); 447 uvmexp.swpgonly -= swpgonlydelta; 448 mutex_exit(&uvm_swap_data_lock); 449 } 450 } 451 452 453 /* 454 * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for non object backed 455 * regions. 456 * 457 * => when you unmap a part of anonymous kernel memory you want to toss 458 * the pages right away. (this is called from uvm_unmap_...). 459 * => none of the pages will ever be busy, and none of them will ever 460 * be on the active or inactive queues (because they have no object). 461 */ 462 463 void 464 uvm_km_pgremove_intrsafe(vaddr_t start, vaddr_t end) 465 { 466 struct vm_page *pg; 467 paddr_t pa; 468 UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist); 469 470 KASSERT(VM_MIN_KERNEL_ADDRESS <= start); 471 KASSERT(start < end); 472 KASSERT(end <= VM_MAX_KERNEL_ADDRESS); 473 474 for (; start < end; start += PAGE_SIZE) { 475 if (!pmap_extract(pmap_kernel(), start, &pa)) { 476 continue; 477 } 478 pg = PHYS_TO_VM_PAGE(pa); 479 KASSERT(pg); 480 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 481 uvm_pagefree(pg); 482 } 483 } 484 485 #if defined(DEBUG) 486 void 487 uvm_km_check_empty(vaddr_t start, vaddr_t end, bool intrsafe) 488 { 489 vaddr_t va; 490 paddr_t pa; 491 492 KDASSERT(VM_MIN_KERNEL_ADDRESS <= start); 493 KDASSERT(start < end); 494 KDASSERT(end <= VM_MAX_KERNEL_ADDRESS); 495 496 for (va = start; va < end; va += PAGE_SIZE) { 497 if (pmap_extract(pmap_kernel(), va, &pa)) { 498 panic("uvm_km_check_empty: va %p has pa 0x%llx", 499 (void *)va, (long long)pa); 500 } 501 if (!intrsafe) { 502 const struct vm_page *pg; 503 504 mutex_enter(&uvm_kernel_object->vmobjlock); 505 pg = uvm_pagelookup(uvm_kernel_object, 506 va - vm_map_min(kernel_map)); 507 mutex_exit(&uvm_kernel_object->vmobjlock); 508 if (pg) { 509 panic("uvm_km_check_empty: " 510 "has page hashed at %p", (const void *)va); 511 } 512 } 513 } 514 } 515 #endif /* defined(DEBUG) */ 516 517 /* 518 * uvm_km_alloc: allocate an area of kernel memory. 519 * 520 * => NOTE: we can return 0 even if we can wait if there is not enough 521 * free VM space in the map... caller should be prepared to handle 522 * this case. 523 * => we return KVA of memory allocated 524 */ 525 526 vaddr_t 527 uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags) 528 { 529 vaddr_t kva, loopva; 530 vaddr_t offset; 531 vsize_t loopsize; 532 struct vm_page *pg; 533 struct uvm_object *obj; 534 int pgaflags; 535 vm_prot_t prot; 536 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 537 538 KASSERT(vm_map_pmap(map) == pmap_kernel()); 539 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 540 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 541 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 542 543 /* 544 * setup for call 545 */ 546 547 kva = vm_map_min(map); /* hint */ 548 size = round_page(size); 549 obj = (flags & UVM_KMF_PAGEABLE) ? uvm_kernel_object : NULL; 550 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 551 map, obj, size, flags); 552 553 /* 554 * allocate some virtual space 555 */ 556 557 if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 558 align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 559 UVM_ADV_RANDOM, 560 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT | UVM_KMF_WAITVA)) 561 | UVM_FLAG_QUANTUM)) != 0)) { 562 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 563 return(0); 564 } 565 566 /* 567 * if all we wanted was VA, return now 568 */ 569 570 if (flags & (UVM_KMF_VAONLY | UVM_KMF_PAGEABLE)) { 571 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 572 return(kva); 573 } 574 575 /* 576 * recover object offset from virtual address 577 */ 578 579 offset = kva - vm_map_min(kernel_map); 580 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 581 582 /* 583 * now allocate and map in the memory... note that we are the only ones 584 * whom should ever get a handle on this area of VM. 585 */ 586 587 loopva = kva; 588 loopsize = size; 589 590 pgaflags = UVM_PGA_USERESERVE; 591 if (flags & UVM_KMF_ZERO) 592 pgaflags |= UVM_PGA_ZERO; 593 prot = VM_PROT_READ | VM_PROT_WRITE; 594 if (flags & UVM_KMF_EXEC) 595 prot |= VM_PROT_EXECUTE; 596 while (loopsize) { 597 KASSERT(!pmap_extract(pmap_kernel(), loopva, NULL)); 598 599 pg = uvm_pagealloc(NULL, offset, NULL, pgaflags); 600 601 /* 602 * out of memory? 603 */ 604 605 if (__predict_false(pg == NULL)) { 606 if ((flags & UVM_KMF_NOWAIT) || 607 ((flags & UVM_KMF_CANFAIL) && !uvm_reclaimable())) { 608 /* free everything! */ 609 uvm_km_free(map, kva, size, 610 flags & UVM_KMF_TYPEMASK); 611 return (0); 612 } else { 613 uvm_wait("km_getwait2"); /* sleep here */ 614 continue; 615 } 616 } 617 618 pg->flags &= ~PG_BUSY; /* new page */ 619 UVM_PAGE_OWN(pg, NULL); 620 621 /* 622 * map it in 623 */ 624 625 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), prot); 626 loopva += PAGE_SIZE; 627 offset += PAGE_SIZE; 628 loopsize -= PAGE_SIZE; 629 } 630 631 pmap_update(pmap_kernel()); 632 633 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 634 return(kva); 635 } 636 637 /* 638 * uvm_km_free: free an area of kernel memory 639 */ 640 641 void 642 uvm_km_free(struct vm_map *map, vaddr_t addr, vsize_t size, uvm_flag_t flags) 643 { 644 645 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 646 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 647 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 648 KASSERT((addr & PAGE_MASK) == 0); 649 KASSERT(vm_map_pmap(map) == pmap_kernel()); 650 651 size = round_page(size); 652 653 if (flags & UVM_KMF_PAGEABLE) { 654 uvm_km_pgremove(addr, addr + size); 655 pmap_remove(pmap_kernel(), addr, addr + size); 656 } else if (flags & UVM_KMF_WIRED) { 657 uvm_km_pgremove_intrsafe(addr, addr + size); 658 pmap_kremove(addr, size); 659 } 660 661 uvm_unmap1(map, addr, addr + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 662 } 663 664 /* Sanity; must specify both or none. */ 665 #if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 666 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 667 #error Must specify MAP and UNMAP together. 668 #endif 669 670 /* 671 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 672 * 673 * => if the pmap specifies an alternate mapping method, we use it. 674 */ 675 676 /* ARGSUSED */ 677 vaddr_t 678 uvm_km_alloc_poolpage_cache(struct vm_map *map, bool waitok) 679 { 680 #if defined(PMAP_MAP_POOLPAGE) 681 return uvm_km_alloc_poolpage(map, waitok); 682 #else 683 struct vm_page *pg; 684 struct pool *pp = &vm_map_to_kernel(map)->vmk_vacache; 685 vaddr_t va; 686 687 if ((map->flags & VM_MAP_VACACHE) == 0) 688 return uvm_km_alloc_poolpage(map, waitok); 689 690 va = (vaddr_t)pool_get(pp, waitok ? PR_WAITOK : PR_NOWAIT); 691 if (va == 0) 692 return 0; 693 KASSERT(!pmap_extract(pmap_kernel(), va, NULL)); 694 again: 695 pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE); 696 if (__predict_false(pg == NULL)) { 697 if (waitok) { 698 uvm_wait("plpg"); 699 goto again; 700 } else { 701 pool_put(pp, (void *)va); 702 return 0; 703 } 704 } 705 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), VM_PROT_READ|VM_PROT_WRITE); 706 pmap_update(pmap_kernel()); 707 708 return va; 709 #endif /* PMAP_MAP_POOLPAGE */ 710 } 711 712 vaddr_t 713 uvm_km_alloc_poolpage(struct vm_map *map, bool waitok) 714 { 715 #if defined(PMAP_MAP_POOLPAGE) 716 struct vm_page *pg; 717 vaddr_t va; 718 719 again: 720 pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE); 721 if (__predict_false(pg == NULL)) { 722 if (waitok) { 723 uvm_wait("plpg"); 724 goto again; 725 } else 726 return (0); 727 } 728 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 729 if (__predict_false(va == 0)) 730 uvm_pagefree(pg); 731 return (va); 732 #else 733 vaddr_t va; 734 735 va = uvm_km_alloc(map, PAGE_SIZE, 0, 736 (waitok ? 0 : UVM_KMF_NOWAIT) | UVM_KMF_WIRED); 737 return (va); 738 #endif /* PMAP_MAP_POOLPAGE */ 739 } 740 741 /* 742 * uvm_km_free_poolpage: free a previously allocated pool page 743 * 744 * => if the pmap specifies an alternate unmapping method, we use it. 745 */ 746 747 /* ARGSUSED */ 748 void 749 uvm_km_free_poolpage_cache(struct vm_map *map, vaddr_t addr) 750 { 751 #if defined(PMAP_UNMAP_POOLPAGE) 752 uvm_km_free_poolpage(map, addr); 753 #else 754 struct pool *pp; 755 756 if ((map->flags & VM_MAP_VACACHE) == 0) { 757 uvm_km_free_poolpage(map, addr); 758 return; 759 } 760 761 KASSERT(pmap_extract(pmap_kernel(), addr, NULL)); 762 uvm_km_pgremove_intrsafe(addr, addr + PAGE_SIZE); 763 pmap_kremove(addr, PAGE_SIZE); 764 #if defined(DEBUG) 765 pmap_update(pmap_kernel()); 766 #endif 767 KASSERT(!pmap_extract(pmap_kernel(), addr, NULL)); 768 pp = &vm_map_to_kernel(map)->vmk_vacache; 769 pool_put(pp, (void *)addr); 770 #endif 771 } 772 773 /* ARGSUSED */ 774 void 775 uvm_km_free_poolpage(struct vm_map *map, vaddr_t addr) 776 { 777 #if defined(PMAP_UNMAP_POOLPAGE) 778 paddr_t pa; 779 780 pa = PMAP_UNMAP_POOLPAGE(addr); 781 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 782 #else 783 uvm_km_free(map, addr, PAGE_SIZE, UVM_KMF_WIRED); 784 #endif /* PMAP_UNMAP_POOLPAGE */ 785 } 786
Indexes created Wed Oct 22 13:09:56 GMT 2025