1 /* $NetBSD: uvm_km.c,v 1.111 2011/09/01 06:40:28 matt 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. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vm_kern.c 8.3 (Berkeley) 1/12/94 37 * from: Id: uvm_km.c,v 1.1.2.14 1998/02/06 05:19:27 chs Exp 38 * 39 * 40 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 41 * All rights reserved. 42 * 43 * Permission to use, copy, modify and distribute this software and 44 * its documentation is hereby granted, provided that both the copyright 45 * notice and this permission notice appear in all copies of the 46 * software, derivative works or modified versions, and any portions 47 * thereof, and that both notices appear in supporting documentation. 48 * 49 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 50 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 51 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 52 * 53 * Carnegie Mellon requests users of this software to return to 54 * 55 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 56 * School of Computer Science 57 * Carnegie Mellon University 58 * Pittsburgh PA 15213-3890 59 * 60 * any improvements or extensions that they make and grant Carnegie the 61 * rights to redistribute these changes. 62 */ 63 64 /* 65 * uvm_km.c: handle kernel memory allocation and management 66 */ 67 68 /* 69 * overview of kernel memory management: 70 * 71 * the kernel virtual address space is mapped by "kernel_map." kernel_map 72 * starts at VM_MIN_KERNEL_ADDRESS and goes to VM_MAX_KERNEL_ADDRESS. 73 * note that VM_MIN_KERNEL_ADDRESS is equal to vm_map_min(kernel_map). 74 * 75 * the kernel_map has several "submaps." submaps can only appear in 76 * the kernel_map (user processes can't use them). submaps "take over" 77 * the management of a sub-range of the kernel's address space. submaps 78 * are typically allocated at boot time and are never released. kernel 79 * virtual address space that is mapped by a submap is locked by the 80 * submap's lock -- not the kernel_map's lock. 81 * 82 * thus, the useful feature of submaps is that they allow us to break 83 * up the locking and protection of the kernel address space into smaller 84 * chunks. 85 * 86 * the vm system has several standard kernel submaps, including: 87 * kmem_map => contains only wired kernel memory for the kernel 88 * malloc. 89 * pager_map => used to map "buf" structures into kernel space 90 * exec_map => used during exec to handle exec args 91 * etc... 92 * 93 * the kernel allocates its private memory out of special uvm_objects whose 94 * reference count is set to UVM_OBJ_KERN (thus indicating that the objects 95 * are "special" and never die). all kernel objects should be thought of 96 * as large, fixed-sized, sparsely populated uvm_objects. each kernel 97 * object is equal to the size of kernel virtual address space (i.e. the 98 * value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS"). 99 * 100 * note that just because a kernel object spans the entire kernel virtual 101 * address space doesn't mean that it has to be mapped into the entire space. 102 * large chunks of a kernel object's space go unused either because 103 * that area of kernel VM is unmapped, or there is some other type of 104 * object mapped into that range (e.g. a vnode). for submap's kernel 105 * objects, the only part of the object that can ever be populated is the 106 * offsets that are managed by the submap. 107 * 108 * note that the "offset" in a kernel object is always the kernel virtual 109 * address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)). 110 * example: 111 * suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a 112 * uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the 113 * kernel map]. if uvm_km_alloc returns virtual address 0xf8235000, 114 * then that means that the page at offset 0x235000 in kernel_object is 115 * mapped at 0xf8235000. 116 * 117 * kernel object have one other special property: when the kernel virtual 118 * memory mapping them is unmapped, the backing memory in the object is 119 * freed right away. this is done with the uvm_km_pgremove() function. 120 * this has to be done because there is no backing store for kernel pages 121 * and no need to save them after they are no longer referenced. 122 */ 123 124 #include <sys/cdefs.h> 125 __KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.111 2011/09/01 06:40:28 matt Exp $"); 126 127 #include "opt_uvmhist.h" 128 129 #include <sys/param.h> 130 #include <sys/malloc.h> 131 #include <sys/systm.h> 132 #include <sys/proc.h> 133 #include <sys/pool.h> 134 135 #include <uvm/uvm.h> 136 137 /* 138 * global data structures 139 */ 140 141 struct vm_map *kernel_map = NULL; 142 143 /* 144 * local data structues 145 */ 146 147 static struct vm_map_kernel kernel_map_store; 148 static struct vm_map_entry kernel_first_mapent_store; 149 150 #if !defined(PMAP_MAP_POOLPAGE) 151 152 /* 153 * kva cache 154 * 155 * XXX maybe it's better to do this at the uvm_map layer. 156 */ 157 158 #define KM_VACACHE_SIZE (32 * PAGE_SIZE) /* XXX tune */ 159 160 static void *km_vacache_alloc(struct pool *, int); 161 static void km_vacache_free(struct pool *, void *); 162 static void km_vacache_init(struct vm_map *, const char *, size_t); 163 164 /* XXX */ 165 #define KM_VACACHE_POOL_TO_MAP(pp) \ 166 ((struct vm_map *)((char *)(pp) - \ 167 offsetof(struct vm_map_kernel, vmk_vacache))) 168 169 static void * 170 km_vacache_alloc(struct pool *pp, int flags) 171 { 172 vaddr_t va; 173 size_t size; 174 struct vm_map *map; 175 size = pp->pr_alloc->pa_pagesz; 176 177 map = KM_VACACHE_POOL_TO_MAP(pp); 178 179 va = vm_map_min(map); /* hint */ 180 if (uvm_map(map, &va, size, NULL, UVM_UNKNOWN_OFFSET, size, 181 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 182 UVM_ADV_RANDOM, UVM_FLAG_QUANTUM | 183 ((flags & PR_WAITOK) ? UVM_FLAG_WAITVA : 184 UVM_FLAG_TRYLOCK | UVM_FLAG_NOWAIT)))) 185 return NULL; 186 187 return (void *)va; 188 } 189 190 static void 191 km_vacache_free(struct pool *pp, void *v) 192 { 193 vaddr_t va = (vaddr_t)v; 194 size_t size = pp->pr_alloc->pa_pagesz; 195 struct vm_map *map; 196 197 map = KM_VACACHE_POOL_TO_MAP(pp); 198 uvm_unmap1(map, va, va + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 199 } 200 201 /* 202 * km_vacache_init: initialize kva cache. 203 */ 204 205 static void 206 km_vacache_init(struct vm_map *map, const char *name, size_t size) 207 { 208 struct vm_map_kernel *vmk; 209 struct pool *pp; 210 struct pool_allocator *pa; 211 int ipl; 212 213 KASSERT(VM_MAP_IS_KERNEL(map)); 214 KASSERT(size < (vm_map_max(map) - vm_map_min(map)) / 2); /* sanity */ 215 216 217 vmk = vm_map_to_kernel(map); 218 pp = &vmk->vmk_vacache; 219 pa = &vmk->vmk_vacache_allocator; 220 memset(pa, 0, sizeof(*pa)); 221 pa->pa_alloc = km_vacache_alloc; 222 pa->pa_free = km_vacache_free; 223 pa->pa_pagesz = (unsigned int)size; 224 pa->pa_backingmap = map; 225 pa->pa_backingmapptr = NULL; 226 227 if ((map->flags & VM_MAP_INTRSAFE) != 0) 228 ipl = IPL_VM; 229 else 230 ipl = IPL_NONE; 231 232 pool_init(pp, PAGE_SIZE, 0, 0, PR_NOTOUCH | PR_RECURSIVE, name, pa, 233 ipl); 234 } 235 236 void 237 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 238 { 239 240 map->flags |= VM_MAP_VACACHE; 241 if (size == 0) 242 size = KM_VACACHE_SIZE; 243 km_vacache_init(map, name, size); 244 } 245 246 #else /* !defined(PMAP_MAP_POOLPAGE) */ 247 248 void 249 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 250 { 251 252 /* nothing */ 253 } 254 255 #endif /* !defined(PMAP_MAP_POOLPAGE) */ 256 257 void 258 uvm_km_va_drain(struct vm_map *map, uvm_flag_t flags) 259 { 260 struct vm_map_kernel *vmk = vm_map_to_kernel(map); 261 262 callback_run_roundrobin(&vmk->vmk_reclaim_callback, NULL); 263 } 264 265 /* 266 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 267 * KVM already allocated for text, data, bss, and static data structures). 268 * 269 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 270 * we assume that [vmin -> start] has already been allocated and that 271 * "end" is the end. 272 */ 273 274 void 275 uvm_km_init(vaddr_t start, vaddr_t end) 276 { 277 vaddr_t base = VM_MIN_KERNEL_ADDRESS; 278 279 /* 280 * next, init kernel memory objects. 281 */ 282 283 /* kernel_object: for pageable anonymous kernel memory */ 284 uao_init(); 285 uvm_kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 286 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 287 288 /* 289 * init the map and reserve any space that might already 290 * have been allocated kernel space before installing. 291 */ 292 293 uvm_map_setup_kernel(&kernel_map_store, base, end, VM_MAP_PAGEABLE); 294 kernel_map_store.vmk_map.pmap = pmap_kernel(); 295 if (start != base) { 296 int error; 297 struct uvm_map_args args; 298 299 error = uvm_map_prepare(&kernel_map_store.vmk_map, 300 base, start - base, 301 NULL, UVM_UNKNOWN_OFFSET, 0, 302 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 303 UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args); 304 if (!error) { 305 kernel_first_mapent_store.flags = 306 UVM_MAP_KERNEL | UVM_MAP_FIRST; 307 error = uvm_map_enter(&kernel_map_store.vmk_map, &args, 308 &kernel_first_mapent_store); 309 } 310 311 if (error) 312 panic( 313 "uvm_km_init: could not reserve space for kernel"); 314 } 315 316 /* 317 * install! 318 */ 319 320 kernel_map = &kernel_map_store.vmk_map; 321 uvm_km_vacache_init(kernel_map, "kvakernel", 0); 322 } 323 324 /* 325 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 326 * is allocated all references to that area of VM must go through it. this 327 * allows the locking of VAs in kernel_map to be broken up into regions. 328 * 329 * => if `fixed' is true, *vmin specifies where the region described 330 * by the submap must start 331 * => if submap is non NULL we use that as the submap, otherwise we 332 * alloc a new map 333 */ 334 335 struct vm_map * 336 uvm_km_suballoc(struct vm_map *map, vaddr_t *vmin /* IN/OUT */, 337 vaddr_t *vmax /* OUT */, vsize_t size, int flags, bool fixed, 338 struct vm_map_kernel *submap) 339 { 340 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 341 342 KASSERT(vm_map_pmap(map) == pmap_kernel()); 343 344 size = round_page(size); /* round up to pagesize */ 345 size += uvm_mapent_overhead(size, flags); 346 347 /* 348 * first allocate a blank spot in the parent map 349 */ 350 351 if (uvm_map(map, vmin, size, NULL, UVM_UNKNOWN_OFFSET, 0, 352 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 353 UVM_ADV_RANDOM, mapflags)) != 0) { 354 panic("uvm_km_suballoc: unable to allocate space in parent map"); 355 } 356 357 /* 358 * set VM bounds (vmin is filled in by uvm_map) 359 */ 360 361 *vmax = *vmin + size; 362 363 /* 364 * add references to pmap and create or init the submap 365 */ 366 367 pmap_reference(vm_map_pmap(map)); 368 if (submap == NULL) { 369 submap = malloc(sizeof(*submap), M_VMMAP, M_WAITOK); 370 if (submap == NULL) 371 panic("uvm_km_suballoc: unable to create submap"); 372 } 373 uvm_map_setup_kernel(submap, *vmin, *vmax, flags); 374 submap->vmk_map.pmap = vm_map_pmap(map); 375 376 /* 377 * now let uvm_map_submap plug in it... 378 */ 379 380 if (uvm_map_submap(map, *vmin, *vmax, &submap->vmk_map) != 0) 381 panic("uvm_km_suballoc: submap allocation failed"); 382 383 return(&submap->vmk_map); 384 } 385 386 /* 387 * uvm_km_pgremove: remove pages from a kernel uvm_object and KVA. 388 */ 389 390 void 391 uvm_km_pgremove(vaddr_t startva, vaddr_t endva) 392 { 393 struct uvm_object * const uobj = uvm_kernel_object; 394 const voff_t start = startva - vm_map_min(kernel_map); 395 const voff_t end = endva - vm_map_min(kernel_map); 396 struct vm_page *pg; 397 voff_t curoff, nextoff; 398 int swpgonlydelta = 0; 399 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 400 401 KASSERT(VM_MIN_KERNEL_ADDRESS <= startva); 402 KASSERT(startva < endva); 403 KASSERT(endva <= VM_MAX_KERNEL_ADDRESS); 404 405 mutex_enter(uobj->vmobjlock); 406 pmap_remove(pmap_kernel(), startva, endva); 407 for (curoff = start; curoff < end; curoff = nextoff) { 408 nextoff = curoff + PAGE_SIZE; 409 pg = uvm_pagelookup(uobj, curoff); 410 if (pg != NULL && pg->flags & PG_BUSY) { 411 pg->flags |= PG_WANTED; 412 UVM_UNLOCK_AND_WAIT(pg, uobj->vmobjlock, 0, 413 "km_pgrm", 0); 414 mutex_enter(uobj->vmobjlock); 415 nextoff = curoff; 416 continue; 417 } 418 419 /* 420 * free the swap slot, then the page. 421 */ 422 423 if (pg == NULL && 424 uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) { 425 swpgonlydelta++; 426 } 427 uao_dropswap(uobj, curoff >> PAGE_SHIFT); 428 if (pg != NULL) { 429 mutex_enter(&uvm_pageqlock); 430 uvm_pagefree(pg); 431 mutex_exit(&uvm_pageqlock); 432 } 433 } 434 mutex_exit(uobj->vmobjlock); 435 436 if (swpgonlydelta > 0) { 437 mutex_enter(&uvm_swap_data_lock); 438 KASSERT(uvmexp.swpgonly >= swpgonlydelta); 439 uvmexp.swpgonly -= swpgonlydelta; 440 mutex_exit(&uvm_swap_data_lock); 441 } 442 } 443 444 445 /* 446 * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for non object backed 447 * regions. 448 * 449 * => when you unmap a part of anonymous kernel memory you want to toss 450 * the pages right away. (this is called from uvm_unmap_...). 451 * => none of the pages will ever be busy, and none of them will ever 452 * be on the active or inactive queues (because they have no object). 453 */ 454 455 void 456 uvm_km_pgremove_intrsafe(struct vm_map *map, vaddr_t start, vaddr_t end) 457 { 458 struct vm_page *pg; 459 paddr_t pa; 460 UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist); 461 462 KASSERT(VM_MAP_IS_KERNEL(map)); 463 KASSERT(vm_map_min(map) <= start); 464 KASSERT(start < end); 465 KASSERT(end <= vm_map_max(map)); 466 467 for (; start < end; start += PAGE_SIZE) { 468 if (!pmap_extract(pmap_kernel(), start, &pa)) { 469 continue; 470 } 471 pg = PHYS_TO_VM_PAGE(pa); 472 KASSERT(pg); 473 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 474 KASSERT((pg->flags & PG_BUSY) == 0); 475 uvm_pagefree(pg); 476 } 477 } 478 479 #if defined(DEBUG) 480 void 481 uvm_km_check_empty(struct vm_map *map, vaddr_t start, vaddr_t end) 482 { 483 struct vm_page *pg; 484 vaddr_t va; 485 paddr_t pa; 486 487 KDASSERT(VM_MAP_IS_KERNEL(map)); 488 KDASSERT(vm_map_min(map) <= start); 489 KDASSERT(start < end); 490 KDASSERT(end <= vm_map_max(map)); 491 492 for (va = start; va < end; va += PAGE_SIZE) { 493 if (pmap_extract(pmap_kernel(), va, &pa)) { 494 panic("uvm_km_check_empty: va %p has pa 0x%llx", 495 (void *)va, (long long)pa); 496 } 497 if ((map->flags & VM_MAP_INTRSAFE) == 0) { 498 mutex_enter(uvm_kernel_object->vmobjlock); 499 pg = uvm_pagelookup(uvm_kernel_object, 500 va - vm_map_min(kernel_map)); 501 mutex_exit(uvm_kernel_object->vmobjlock); 502 if (pg) { 503 panic("uvm_km_check_empty: " 504 "has page hashed at %p", (const void *)va); 505 } 506 } 507 } 508 } 509 #endif /* defined(DEBUG) */ 510 511 /* 512 * uvm_km_alloc: allocate an area of kernel memory. 513 * 514 * => NOTE: we can return 0 even if we can wait if there is not enough 515 * free VM space in the map... caller should be prepared to handle 516 * this case. 517 * => we return KVA of memory allocated 518 */ 519 520 vaddr_t 521 uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags) 522 { 523 vaddr_t kva, loopva; 524 vaddr_t offset; 525 vsize_t loopsize; 526 struct vm_page *pg; 527 struct uvm_object *obj; 528 int pgaflags; 529 vm_prot_t prot; 530 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 531 532 KASSERT(vm_map_pmap(map) == pmap_kernel()); 533 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 534 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 535 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 536 KASSERT((flags & UVM_KMF_VAONLY) != 0 || (flags & UVM_KMF_COLORMATCH) == 0); 537 KASSERT((flags & UVM_KMF_COLORMATCH) == 0 || (flags & UVM_KMF_VAONLY) != 0); 538 539 /* 540 * setup for call 541 */ 542 543 kva = vm_map_min(map); /* hint */ 544 size = round_page(size); 545 obj = (flags & UVM_KMF_PAGEABLE) ? uvm_kernel_object : NULL; 546 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 547 map, obj, size, flags); 548 549 /* 550 * allocate some virtual space 551 */ 552 553 if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 554 align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 555 UVM_ADV_RANDOM, 556 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT | UVM_KMF_WAITVA 557 | UVM_KMF_COLORMATCH)) 558 | UVM_FLAG_QUANTUM)) != 0)) { 559 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 560 return(0); 561 } 562 563 /* 564 * if all we wanted was VA, return now 565 */ 566 567 if (flags & (UVM_KMF_VAONLY | UVM_KMF_PAGEABLE)) { 568 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 569 return(kva); 570 } 571 572 /* 573 * recover object offset from virtual address 574 */ 575 576 offset = kva - vm_map_min(kernel_map); 577 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 578 579 /* 580 * now allocate and map in the memory... note that we are the only ones 581 * whom should ever get a handle on this area of VM. 582 */ 583 584 loopva = kva; 585 loopsize = size; 586 587 pgaflags = UVM_FLAG_COLORMATCH; 588 if (flags & UVM_KMF_NOWAIT) 589 pgaflags |= UVM_PGA_USERESERVE; 590 if (flags & UVM_KMF_ZERO) 591 pgaflags |= UVM_PGA_ZERO; 592 prot = VM_PROT_READ | VM_PROT_WRITE; 593 if (flags & UVM_KMF_EXEC) 594 prot |= VM_PROT_EXECUTE; 595 while (loopsize) { 596 KASSERT(!pmap_extract(pmap_kernel(), loopva, NULL)); 597 598 pg = uvm_pagealloc_strat(NULL, offset, NULL, pgaflags, 599 #ifdef UVM_KM_VMFREELIST 600 UVM_PGA_STRAT_ONLY, UVM_KM_VMFREELIST 601 #else 602 UVM_PGA_STRAT_NORMAL, 0 603 #endif 604 ); 605 606 /* 607 * out of memory? 608 */ 609 610 if (__predict_false(pg == NULL)) { 611 if ((flags & UVM_KMF_NOWAIT) || 612 ((flags & UVM_KMF_CANFAIL) && !uvm_reclaimable())) { 613 /* free everything! */ 614 uvm_km_free(map, kva, size, 615 flags & UVM_KMF_TYPEMASK); 616 return (0); 617 } else { 618 uvm_wait("km_getwait2"); /* sleep here */ 619 continue; 620 } 621 } 622 623 pg->flags &= ~PG_BUSY; /* new page */ 624 UVM_PAGE_OWN(pg, NULL); 625 626 /* 627 * map it in 628 */ 629 630 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), 631 prot, PMAP_KMPAGE); 632 loopva += PAGE_SIZE; 633 offset += PAGE_SIZE; 634 loopsize -= PAGE_SIZE; 635 } 636 637 pmap_update(pmap_kernel()); 638 639 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 640 return(kva); 641 } 642 643 /* 644 * uvm_km_free: free an area of kernel memory 645 */ 646 647 void 648 uvm_km_free(struct vm_map *map, vaddr_t addr, vsize_t size, uvm_flag_t flags) 649 { 650 651 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 652 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 653 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 654 KASSERT((addr & PAGE_MASK) == 0); 655 KASSERT(vm_map_pmap(map) == pmap_kernel()); 656 657 size = round_page(size); 658 659 if (flags & UVM_KMF_PAGEABLE) { 660 uvm_km_pgremove(addr, addr + size); 661 } else if (flags & UVM_KMF_WIRED) { 662 /* 663 * Note: uvm_km_pgremove_intrsafe() extracts mapping, thus 664 * remove it after. See comment below about KVA visibility. 665 */ 666 uvm_km_pgremove_intrsafe(map, addr, addr + size); 667 pmap_kremove(addr, size); 668 } 669 670 /* 671 * Note: uvm_unmap_remove() calls pmap_update() for us, before 672 * KVA becomes globally available. 673 */ 674 675 uvm_unmap1(map, addr, addr + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 676 } 677 678 /* Sanity; must specify both or none. */ 679 #if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 680 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 681 #error Must specify MAP and UNMAP together. 682 #endif 683 684 /* 685 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 686 * 687 * => if the pmap specifies an alternate mapping method, we use it. 688 */ 689 690 /* ARGSUSED */ 691 vaddr_t 692 uvm_km_alloc_poolpage_cache(struct vm_map *map, bool waitok) 693 { 694 #if defined(PMAP_MAP_POOLPAGE) 695 return uvm_km_alloc_poolpage(map, waitok); 696 #else 697 struct vm_page *pg; 698 struct pool *pp = &vm_map_to_kernel(map)->vmk_vacache; 699 vaddr_t va; 700 701 if ((map->flags & VM_MAP_VACACHE) == 0) 702 return uvm_km_alloc_poolpage(map, waitok); 703 704 va = (vaddr_t)pool_get(pp, waitok ? PR_WAITOK : PR_NOWAIT); 705 if (va == 0) 706 return 0; 707 KASSERT(!pmap_extract(pmap_kernel(), va, NULL)); 708 again: 709 pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE); 710 if (__predict_false(pg == NULL)) { 711 if (waitok) { 712 uvm_wait("plpg"); 713 goto again; 714 } else { 715 pool_put(pp, (void *)va); 716 return 0; 717 } 718 } 719 pg->flags &= ~PG_BUSY; /* new page */ 720 UVM_PAGE_OWN(pg, NULL); 721 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), 722 VM_PROT_READ|VM_PROT_WRITE, PMAP_KMPAGE); 723 pmap_update(pmap_kernel()); 724 725 return va; 726 #endif /* PMAP_MAP_POOLPAGE */ 727 } 728 729 vaddr_t 730 uvm_km_alloc_poolpage(struct vm_map *map, bool waitok) 731 { 732 #if defined(PMAP_MAP_POOLPAGE) 733 struct vm_page *pg; 734 vaddr_t va; 735 736 737 again: 738 #ifdef PMAP_ALLOC_POOLPAGE 739 pg = PMAP_ALLOC_POOLPAGE(waitok ? 0 : UVM_PGA_USERESERVE); 740 #else 741 pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE); 742 #endif 743 if (__predict_false(pg == NULL)) { 744 if (waitok) { 745 uvm_wait("plpg"); 746 goto again; 747 } else 748 return (0); 749 } 750 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 751 if (__predict_false(va == 0)) 752 uvm_pagefree(pg); 753 return (va); 754 #else 755 vaddr_t va; 756 757 va = uvm_km_alloc(map, PAGE_SIZE, 0, 758 (waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK) | UVM_KMF_WIRED); 759 return (va); 760 #endif /* PMAP_MAP_POOLPAGE */ 761 } 762 763 /* 764 * uvm_km_free_poolpage: free a previously allocated pool page 765 * 766 * => if the pmap specifies an alternate unmapping method, we use it. 767 */ 768 769 /* ARGSUSED */ 770 void 771 uvm_km_free_poolpage_cache(struct vm_map *map, vaddr_t addr) 772 { 773 #if defined(PMAP_UNMAP_POOLPAGE) 774 uvm_km_free_poolpage(map, addr); 775 #else 776 struct pool *pp; 777 778 if ((map->flags & VM_MAP_VACACHE) == 0) { 779 uvm_km_free_poolpage(map, addr); 780 return; 781 } 782 783 KASSERT(pmap_extract(pmap_kernel(), addr, NULL)); 784 uvm_km_pgremove_intrsafe(map, addr, addr + PAGE_SIZE); 785 pmap_kremove(addr, PAGE_SIZE); 786 #if defined(DEBUG) 787 pmap_update(pmap_kernel()); 788 #endif 789 KASSERT(!pmap_extract(pmap_kernel(), addr, NULL)); 790 pp = &vm_map_to_kernel(map)->vmk_vacache; 791 pool_put(pp, (void *)addr); 792 #endif 793 } 794 795 /* ARGSUSED */ 796 void 797 uvm_km_free_poolpage(struct vm_map *map, vaddr_t addr) 798 { 799 #if defined(PMAP_UNMAP_POOLPAGE) 800 paddr_t pa; 801 802 pa = PMAP_UNMAP_POOLPAGE(addr); 803 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 804 #else 805 uvm_km_free(map, addr, PAGE_SIZE, UVM_KMF_WIRED); 806 #endif /* PMAP_UNMAP_POOLPAGE */ 807 } 808