1 /* $NetBSD: uvm_km.c,v 1.106 2010/05/14 05:02:06 cegger 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@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 * pager_map => used to map "buf" structures into kernel space 95 * exec_map => used during exec to handle exec args 96 * etc... 97 * 98 * the kernel allocates its private memory out of special uvm_objects whose 99 * reference count is set to UVM_OBJ_KERN (thus indicating that the objects 100 * are "special" and never die). all kernel objects should be thought of 101 * as large, fixed-sized, sparsely populated uvm_objects. each kernel 102 * object is equal to the size of kernel virtual address space (i.e. the 103 * value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS"). 104 * 105 * note that just because a kernel object spans the entire kernel virtual 106 * address space doesn't mean that it has to be mapped into the entire space. 107 * large chunks of a kernel object's space go unused either because 108 * that area of kernel VM is unmapped, or there is some other type of 109 * object mapped into that range (e.g. a vnode). for submap's kernel 110 * objects, the only part of the object that can ever be populated is the 111 * offsets that are managed by the submap. 112 * 113 * note that the "offset" in a kernel object is always the kernel virtual 114 * address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)). 115 * example: 116 * suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a 117 * uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the 118 * kernel map]. if uvm_km_alloc returns virtual address 0xf8235000, 119 * then that means that the page at offset 0x235000 in kernel_object is 120 * mapped at 0xf8235000. 121 * 122 * kernel object have one other special property: when the kernel virtual 123 * memory mapping them is unmapped, the backing memory in the object is 124 * freed right away. this is done with the uvm_km_pgremove() function. 125 * this has to be done because there is no backing store for kernel pages 126 * and no need to save them after they are no longer referenced. 127 */ 128 129 #include <sys/cdefs.h> 130 __KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.106 2010/05/14 05:02:06 cegger Exp $"); 131 132 #include "opt_uvmhist.h" 133 134 #include <sys/param.h> 135 #include <sys/malloc.h> 136 #include <sys/systm.h> 137 #include <sys/proc.h> 138 #include <sys/pool.h> 139 140 #include <uvm/uvm.h> 141 142 /* 143 * global data structures 144 */ 145 146 struct vm_map *kernel_map = NULL; 147 148 /* 149 * local data structues 150 */ 151 152 static struct vm_map_kernel kernel_map_store; 153 static struct vm_map_entry kernel_first_mapent_store; 154 155 #if !defined(PMAP_MAP_POOLPAGE) 156 157 /* 158 * kva cache 159 * 160 * XXX maybe it's better to do this at the uvm_map layer. 161 */ 162 163 #define KM_VACACHE_SIZE (32 * PAGE_SIZE) /* XXX tune */ 164 165 static void *km_vacache_alloc(struct pool *, int); 166 static void km_vacache_free(struct pool *, void *); 167 static void km_vacache_init(struct vm_map *, const char *, size_t); 168 169 /* XXX */ 170 #define KM_VACACHE_POOL_TO_MAP(pp) \ 171 ((struct vm_map *)((char *)(pp) - \ 172 offsetof(struct vm_map_kernel, vmk_vacache))) 173 174 static void * 175 km_vacache_alloc(struct pool *pp, int flags) 176 { 177 vaddr_t va; 178 size_t size; 179 struct vm_map *map; 180 size = pp->pr_alloc->pa_pagesz; 181 182 map = KM_VACACHE_POOL_TO_MAP(pp); 183 184 va = vm_map_min(map); /* hint */ 185 if (uvm_map(map, &va, size, NULL, UVM_UNKNOWN_OFFSET, size, 186 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 187 UVM_ADV_RANDOM, UVM_FLAG_QUANTUM | 188 ((flags & PR_WAITOK) ? UVM_FLAG_WAITVA : 189 UVM_FLAG_TRYLOCK | 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(struct vm_map *map, 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_MAP_IS_KERNEL(map)); 471 KASSERT(vm_map_min(map) <= start); 472 KASSERT(start < end); 473 KASSERT(end <= vm_map_max(map)); 474 475 for (; start < end; start += PAGE_SIZE) { 476 if (!pmap_extract(pmap_kernel(), start, &pa)) { 477 continue; 478 } 479 pg = PHYS_TO_VM_PAGE(pa); 480 KASSERT(pg); 481 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 482 uvm_pagefree(pg); 483 } 484 } 485 486 #if defined(DEBUG) 487 void 488 uvm_km_check_empty(struct vm_map *map, vaddr_t start, vaddr_t end) 489 { 490 struct vm_page *pg; 491 vaddr_t va; 492 paddr_t pa; 493 494 KDASSERT(VM_MAP_IS_KERNEL(map)); 495 KDASSERT(vm_map_min(map) <= start); 496 KDASSERT(start < end); 497 KDASSERT(end <= vm_map_max(map)); 498 499 for (va = start; va < end; va += PAGE_SIZE) { 500 if (pmap_extract(pmap_kernel(), va, &pa)) { 501 panic("uvm_km_check_empty: va %p has pa 0x%llx", 502 (void *)va, (long long)pa); 503 } 504 if ((map->flags & VM_MAP_INTRSAFE) == 0) { 505 mutex_enter(&uvm_kernel_object->vmobjlock); 506 pg = uvm_pagelookup(uvm_kernel_object, 507 va - vm_map_min(kernel_map)); 508 mutex_exit(&uvm_kernel_object->vmobjlock); 509 if (pg) { 510 panic("uvm_km_check_empty: " 511 "has page hashed at %p", (const void *)va); 512 } 513 } 514 } 515 } 516 #endif /* defined(DEBUG) */ 517 518 /* 519 * uvm_km_alloc: allocate an area of kernel memory. 520 * 521 * => NOTE: we can return 0 even if we can wait if there is not enough 522 * free VM space in the map... caller should be prepared to handle 523 * this case. 524 * => we return KVA of memory allocated 525 */ 526 527 vaddr_t 528 uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags) 529 { 530 vaddr_t kva, loopva; 531 vaddr_t offset; 532 vsize_t loopsize; 533 struct vm_page *pg; 534 struct uvm_object *obj; 535 int pgaflags; 536 vm_prot_t prot; 537 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 538 539 KASSERT(vm_map_pmap(map) == pmap_kernel()); 540 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 541 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 542 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 543 544 /* 545 * setup for call 546 */ 547 548 kva = vm_map_min(map); /* hint */ 549 size = round_page(size); 550 obj = (flags & UVM_KMF_PAGEABLE) ? uvm_kernel_object : NULL; 551 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 552 map, obj, size, flags); 553 554 /* 555 * allocate some virtual space 556 */ 557 558 if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 559 align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 560 UVM_ADV_RANDOM, 561 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT | UVM_KMF_WAITVA)) 562 | UVM_FLAG_QUANTUM)) != 0)) { 563 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 564 return(0); 565 } 566 567 /* 568 * if all we wanted was VA, return now 569 */ 570 571 if (flags & (UVM_KMF_VAONLY | UVM_KMF_PAGEABLE)) { 572 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 573 return(kva); 574 } 575 576 /* 577 * recover object offset from virtual address 578 */ 579 580 offset = kva - vm_map_min(kernel_map); 581 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 582 583 /* 584 * now allocate and map in the memory... note that we are the only ones 585 * whom should ever get a handle on this area of VM. 586 */ 587 588 loopva = kva; 589 loopsize = size; 590 591 pgaflags = 0; 592 if (flags & UVM_KMF_NOWAIT) 593 pgaflags |= UVM_PGA_USERESERVE; 594 if (flags & UVM_KMF_ZERO) 595 pgaflags |= UVM_PGA_ZERO; 596 prot = VM_PROT_READ | VM_PROT_WRITE; 597 if (flags & UVM_KMF_EXEC) 598 prot |= VM_PROT_EXECUTE; 599 while (loopsize) { 600 KASSERT(!pmap_extract(pmap_kernel(), loopva, NULL)); 601 602 pg = uvm_pagealloc(NULL, offset, NULL, pgaflags); 603 604 /* 605 * out of memory? 606 */ 607 608 if (__predict_false(pg == NULL)) { 609 if ((flags & UVM_KMF_NOWAIT) || 610 ((flags & UVM_KMF_CANFAIL) && !uvm_reclaimable())) { 611 /* free everything! */ 612 uvm_km_free(map, kva, size, 613 flags & UVM_KMF_TYPEMASK); 614 return (0); 615 } else { 616 uvm_wait("km_getwait2"); /* sleep here */ 617 continue; 618 } 619 } 620 621 pg->flags &= ~PG_BUSY; /* new page */ 622 UVM_PAGE_OWN(pg, NULL); 623 624 /* 625 * map it in 626 */ 627 628 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), 629 prot, PMAP_KMPAGE); 630 loopva += PAGE_SIZE; 631 offset += PAGE_SIZE; 632 loopsize -= PAGE_SIZE; 633 } 634 635 pmap_update(pmap_kernel()); 636 637 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 638 return(kva); 639 } 640 641 /* 642 * uvm_km_free: free an area of kernel memory 643 */ 644 645 void 646 uvm_km_free(struct vm_map *map, vaddr_t addr, vsize_t size, uvm_flag_t flags) 647 { 648 649 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 650 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 651 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 652 KASSERT((addr & PAGE_MASK) == 0); 653 KASSERT(vm_map_pmap(map) == pmap_kernel()); 654 655 size = round_page(size); 656 657 if (flags & UVM_KMF_PAGEABLE) { 658 uvm_km_pgremove(addr, addr + size); 659 pmap_remove(pmap_kernel(), addr, addr + size); 660 } else if (flags & UVM_KMF_WIRED) { 661 uvm_km_pgremove_intrsafe(map, addr, addr + size); 662 pmap_kremove(addr, size); 663 } 664 665 /* 666 * uvm_unmap_remove calls pmap_update for us. 667 */ 668 669 uvm_unmap1(map, addr, addr + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 670 } 671 672 /* Sanity; must specify both or none. */ 673 #if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 674 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 675 #error Must specify MAP and UNMAP together. 676 #endif 677 678 /* 679 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 680 * 681 * => if the pmap specifies an alternate mapping method, we use it. 682 */ 683 684 /* ARGSUSED */ 685 vaddr_t 686 uvm_km_alloc_poolpage_cache(struct vm_map *map, bool waitok) 687 { 688 #if defined(PMAP_MAP_POOLPAGE) 689 return uvm_km_alloc_poolpage(map, waitok); 690 #else 691 struct vm_page *pg; 692 struct pool *pp = &vm_map_to_kernel(map)->vmk_vacache; 693 vaddr_t va; 694 695 if ((map->flags & VM_MAP_VACACHE) == 0) 696 return uvm_km_alloc_poolpage(map, waitok); 697 698 va = (vaddr_t)pool_get(pp, waitok ? PR_WAITOK : PR_NOWAIT); 699 if (va == 0) 700 return 0; 701 KASSERT(!pmap_extract(pmap_kernel(), va, NULL)); 702 again: 703 pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE); 704 if (__predict_false(pg == NULL)) { 705 if (waitok) { 706 uvm_wait("plpg"); 707 goto again; 708 } else { 709 pool_put(pp, (void *)va); 710 return 0; 711 } 712 } 713 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), 714 VM_PROT_READ|VM_PROT_WRITE, PMAP_KMPAGE); 715 pmap_update(pmap_kernel()); 716 717 return va; 718 #endif /* PMAP_MAP_POOLPAGE */ 719 } 720 721 vaddr_t 722 uvm_km_alloc_poolpage(struct vm_map *map, bool waitok) 723 { 724 #if defined(PMAP_MAP_POOLPAGE) 725 struct vm_page *pg; 726 vaddr_t va; 727 728 again: 729 pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE); 730 if (__predict_false(pg == NULL)) { 731 if (waitok) { 732 uvm_wait("plpg"); 733 goto again; 734 } else 735 return (0); 736 } 737 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 738 if (__predict_false(va == 0)) 739 uvm_pagefree(pg); 740 return (va); 741 #else 742 vaddr_t va; 743 744 va = uvm_km_alloc(map, PAGE_SIZE, 0, 745 (waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK) | UVM_KMF_WIRED); 746 return (va); 747 #endif /* PMAP_MAP_POOLPAGE */ 748 } 749 750 /* 751 * uvm_km_free_poolpage: free a previously allocated pool page 752 * 753 * => if the pmap specifies an alternate unmapping method, we use it. 754 */ 755 756 /* ARGSUSED */ 757 void 758 uvm_km_free_poolpage_cache(struct vm_map *map, vaddr_t addr) 759 { 760 #if defined(PMAP_UNMAP_POOLPAGE) 761 uvm_km_free_poolpage(map, addr); 762 #else 763 struct pool *pp; 764 765 if ((map->flags & VM_MAP_VACACHE) == 0) { 766 uvm_km_free_poolpage(map, addr); 767 return; 768 } 769 770 KASSERT(pmap_extract(pmap_kernel(), addr, NULL)); 771 uvm_km_pgremove_intrsafe(map, addr, addr + PAGE_SIZE); 772 pmap_kremove(addr, PAGE_SIZE); 773 #if defined(DEBUG) 774 pmap_update(pmap_kernel()); 775 #endif 776 KASSERT(!pmap_extract(pmap_kernel(), addr, NULL)); 777 pp = &vm_map_to_kernel(map)->vmk_vacache; 778 pool_put(pp, (void *)addr); 779 #endif 780 } 781 782 /* ARGSUSED */ 783 void 784 uvm_km_free_poolpage(struct vm_map *map, vaddr_t addr) 785 { 786 #if defined(PMAP_UNMAP_POOLPAGE) 787 paddr_t pa; 788 789 pa = PMAP_UNMAP_POOLPAGE(addr); 790 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 791 #else 792 uvm_km_free(map, addr, PAGE_SIZE, UVM_KMF_WIRED); 793 #endif /* PMAP_UNMAP_POOLPAGE */ 794 } 795