1 /* $NetBSD: uvm_km.c,v 1.103 2008/12/13 11:34:43 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@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 virtual 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 1.103 2008/12/13 11:34:43 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 : 190 UVM_FLAG_TRYLOCK | UVM_FLAG_NOWAIT)))) 191 return NULL; 192 193 return (void *)va; 194 } 195 196 static void 197 km_vacache_free(struct pool *pp, void *v) 198 { 199 vaddr_t va = (vaddr_t)v; 200 size_t size = pp->pr_alloc->pa_pagesz; 201 struct vm_map *map; 202 203 map = KM_VACACHE_POOL_TO_MAP(pp); 204 uvm_unmap1(map, va, va + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY); 205 } 206 207 /* 208 * km_vacache_init: initialize kva cache. 209 */ 210 211 static void 212 km_vacache_init(struct vm_map *map, const char *name, size_t size) 213 { 214 struct vm_map_kernel *vmk; 215 struct pool *pp; 216 struct pool_allocator *pa; 217 int ipl; 218 219 KASSERT(VM_MAP_IS_KERNEL(map)); 220 KASSERT(size < (vm_map_max(map) - vm_map_min(map)) / 2); /* sanity */ 221 222 223 vmk = vm_map_to_kernel(map); 224 pp = &vmk->vmk_vacache; 225 pa = &vmk->vmk_vacache_allocator; 226 memset(pa, 0, sizeof(*pa)); 227 pa->pa_alloc = km_vacache_alloc; 228 pa->pa_free = km_vacache_free; 229 pa->pa_pagesz = (unsigned int)size; 230 pa->pa_backingmap = map; 231 pa->pa_backingmapptr = NULL; 232 233 if ((map->flags & VM_MAP_INTRSAFE) != 0) 234 ipl = IPL_VM; 235 else 236 ipl = IPL_NONE; 237 238 pool_init(pp, PAGE_SIZE, 0, 0, PR_NOTOUCH | PR_RECURSIVE, name, pa, 239 ipl); 240 } 241 242 void 243 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 244 { 245 246 map->flags |= VM_MAP_VACACHE; 247 if (size == 0) 248 size = KM_VACACHE_SIZE; 249 km_vacache_init(map, name, size); 250 } 251 252 #else /* !defined(PMAP_MAP_POOLPAGE) */ 253 254 void 255 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size) 256 { 257 258 /* nothing */ 259 } 260 261 #endif /* !defined(PMAP_MAP_POOLPAGE) */ 262 263 void 264 uvm_km_va_drain(struct vm_map *map, uvm_flag_t flags) 265 { 266 struct vm_map_kernel *vmk = vm_map_to_kernel(map); 267 268 callback_run_roundrobin(&vmk->vmk_reclaim_callback, NULL); 269 } 270 271 /* 272 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 273 * KVM already allocated for text, data, bss, and static data structures). 274 * 275 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 276 * we assume that [vmin -> start] has already been allocated and that 277 * "end" is the end. 278 */ 279 280 void 281 uvm_km_init(vaddr_t start, vaddr_t end) 282 { 283 vaddr_t base = VM_MIN_KERNEL_ADDRESS; 284 285 /* 286 * next, init kernel memory objects. 287 */ 288 289 /* kernel_object: for pageable anonymous kernel memory */ 290 uao_init(); 291 uvm_kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 292 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 293 294 /* 295 * init the map and reserve any space that might already 296 * have been allocated kernel space before installing. 297 */ 298 299 uvm_map_setup_kernel(&kernel_map_store, base, end, VM_MAP_PAGEABLE); 300 kernel_map_store.vmk_map.pmap = pmap_kernel(); 301 if (start != base) { 302 int error; 303 struct uvm_map_args args; 304 305 error = uvm_map_prepare(&kernel_map_store.vmk_map, 306 base, start - base, 307 NULL, UVM_UNKNOWN_OFFSET, 0, 308 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 309 UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args); 310 if (!error) { 311 kernel_first_mapent_store.flags = 312 UVM_MAP_KERNEL | UVM_MAP_FIRST; 313 error = uvm_map_enter(&kernel_map_store.vmk_map, &args, 314 &kernel_first_mapent_store); 315 } 316 317 if (error) 318 panic( 319 "uvm_km_init: could not reserve space for kernel"); 320 } 321 322 /* 323 * install! 324 */ 325 326 kernel_map = &kernel_map_store.vmk_map; 327 uvm_km_vacache_init(kernel_map, "kvakernel", 0); 328 } 329 330 /* 331 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 332 * is allocated all references to that area of VM must go through it. this 333 * allows the locking of VAs in kernel_map to be broken up into regions. 334 * 335 * => if `fixed' is true, *vmin specifies where the region described 336 * by the submap must start 337 * => if submap is non NULL we use that as the submap, otherwise we 338 * alloc a new map 339 */ 340 341 struct vm_map * 342 uvm_km_suballoc(struct vm_map *map, vaddr_t *vmin /* IN/OUT */, 343 vaddr_t *vmax /* OUT */, vsize_t size, int flags, bool fixed, 344 struct vm_map_kernel *submap) 345 { 346 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 347 348 KASSERT(vm_map_pmap(map) == pmap_kernel()); 349 350 size = round_page(size); /* round up to pagesize */ 351 size += uvm_mapent_overhead(size, flags); 352 353 /* 354 * first allocate a blank spot in the parent map 355 */ 356 357 if (uvm_map(map, vmin, size, NULL, UVM_UNKNOWN_OFFSET, 0, 358 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 359 UVM_ADV_RANDOM, mapflags)) != 0) { 360 panic("uvm_km_suballoc: unable to allocate space in parent map"); 361 } 362 363 /* 364 * set VM bounds (vmin is filled in by uvm_map) 365 */ 366 367 *vmax = *vmin + size; 368 369 /* 370 * add references to pmap and create or init the submap 371 */ 372 373 pmap_reference(vm_map_pmap(map)); 374 if (submap == NULL) { 375 submap = malloc(sizeof(*submap), M_VMMAP, M_WAITOK); 376 if (submap == NULL) 377 panic("uvm_km_suballoc: unable to create submap"); 378 } 379 uvm_map_setup_kernel(submap, *vmin, *vmax, flags); 380 submap->vmk_map.pmap = vm_map_pmap(map); 381 382 /* 383 * now let uvm_map_submap plug in it... 384 */ 385 386 if (uvm_map_submap(map, *vmin, *vmax, &submap->vmk_map) != 0) 387 panic("uvm_km_suballoc: submap allocation failed"); 388 389 return(&submap->vmk_map); 390 } 391 392 /* 393 * uvm_km_pgremove: remove pages from a kernel uvm_object. 394 * 395 * => when you unmap a part of anonymous kernel memory you want to toss 396 * the pages right away. (this gets called from uvm_unmap_...). 397 */ 398 399 void 400 uvm_km_pgremove(vaddr_t startva, vaddr_t endva) 401 { 402 struct uvm_object * const uobj = uvm_kernel_object; 403 const voff_t start = startva - vm_map_min(kernel_map); 404 const voff_t end = endva - vm_map_min(kernel_map); 405 struct vm_page *pg; 406 voff_t curoff, nextoff; 407 int swpgonlydelta = 0; 408 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 409 410 KASSERT(VM_MIN_KERNEL_ADDRESS <= startva); 411 KASSERT(startva < endva); 412 KASSERT(endva <= VM_MAX_KERNEL_ADDRESS); 413 414 mutex_enter(&uobj->vmobjlock); 415 416 for (curoff = start; curoff < end; curoff = nextoff) { 417 nextoff = curoff + PAGE_SIZE; 418 pg = uvm_pagelookup(uobj, curoff); 419 if (pg != NULL && pg->flags & PG_BUSY) { 420 pg->flags |= PG_WANTED; 421 UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, 422 "km_pgrm", 0); 423 mutex_enter(&uobj->vmobjlock); 424 nextoff = curoff; 425 continue; 426 } 427 428 /* 429 * free the swap slot, then the page. 430 */ 431 432 if (pg == NULL && 433 uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) { 434 swpgonlydelta++; 435 } 436 uao_dropswap(uobj, curoff >> PAGE_SHIFT); 437 if (pg != NULL) { 438 mutex_enter(&uvm_pageqlock); 439 uvm_pagefree(pg); 440 mutex_exit(&uvm_pageqlock); 441 } 442 } 443 mutex_exit(&uobj->vmobjlock); 444 445 if (swpgonlydelta > 0) { 446 mutex_enter(&uvm_swap_data_lock); 447 KASSERT(uvmexp.swpgonly >= swpgonlydelta); 448 uvmexp.swpgonly -= swpgonlydelta; 449 mutex_exit(&uvm_swap_data_lock); 450 } 451 } 452 453 454 /* 455 * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for non object backed 456 * regions. 457 * 458 * => when you unmap a part of anonymous kernel memory you want to toss 459 * the pages right away. (this is called from uvm_unmap_...). 460 * => none of the pages will ever be busy, and none of them will ever 461 * be on the active or inactive queues (because they have no object). 462 */ 463 464 void 465 uvm_km_pgremove_intrsafe(struct vm_map *map, vaddr_t start, vaddr_t end) 466 { 467 struct vm_page *pg; 468 paddr_t pa; 469 UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist); 470 471 KASSERT(VM_MAP_IS_KERNEL(map)); 472 KASSERT(vm_map_min(map) <= start); 473 KASSERT(start < end); 474 KASSERT(end <= vm_map_max(map)); 475 476 for (; start < end; start += PAGE_SIZE) { 477 if (!pmap_extract(pmap_kernel(), start, &pa)) { 478 continue; 479 } 480 pg = PHYS_TO_VM_PAGE(pa); 481 KASSERT(pg); 482 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 483 uvm_pagefree(pg); 484 } 485 } 486 487 #if defined(DEBUG) 488 void 489 uvm_km_check_empty(struct vm_map *map, vaddr_t start, vaddr_t end) 490 { 491 struct vm_page *pg; 492 vaddr_t va; 493 paddr_t pa; 494 495 KDASSERT(VM_MAP_IS_KERNEL(map)); 496 KDASSERT(vm_map_min(map) <= start); 497 KDASSERT(start < end); 498 KDASSERT(end <= vm_map_max(map)); 499 500 for (va = start; va < end; va += PAGE_SIZE) { 501 if (pmap_extract(pmap_kernel(), va, &pa)) { 502 panic("uvm_km_check_empty: va %p has pa 0x%llx", 503 (void *)va, (long long)pa); 504 } 505 if ((map->flags & VM_MAP_INTRSAFE) == 0) { 506 mutex_enter(&uvm_kernel_object->vmobjlock); 507 pg = uvm_pagelookup(uvm_kernel_object, 508 va - vm_map_min(kernel_map)); 509 mutex_exit(&uvm_kernel_object->vmobjlock); 510 if (pg) { 511 panic("uvm_km_check_empty: " 512 "has page hashed at %p", (const void *)va); 513 } 514 } 515 } 516 } 517 #endif /* defined(DEBUG) */ 518 519 /* 520 * uvm_km_alloc: allocate an area of kernel memory. 521 * 522 * => NOTE: we can return 0 even if we can wait if there is not enough 523 * free VM space in the map... caller should be prepared to handle 524 * this case. 525 * => we return KVA of memory allocated 526 */ 527 528 vaddr_t 529 uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags) 530 { 531 vaddr_t kva, loopva; 532 vaddr_t offset; 533 vsize_t loopsize; 534 struct vm_page *pg; 535 struct uvm_object *obj; 536 int pgaflags; 537 vm_prot_t prot; 538 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 539 540 KASSERT(vm_map_pmap(map) == pmap_kernel()); 541 KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED || 542 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE || 543 (flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY); 544 545 /* 546 * setup for call 547 */ 548 549 kva = vm_map_min(map); /* hint */ 550 size = round_page(size); 551 obj = (flags & UVM_KMF_PAGEABLE) ? uvm_kernel_object : NULL; 552 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 553 map, obj, size, flags); 554 555 /* 556 * allocate some virtual space 557 */ 558 559 if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 560 align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 561 UVM_ADV_RANDOM, 562 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT | UVM_KMF_WAITVA)) 563 | UVM_FLAG_QUANTUM)) != 0)) { 564 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 565 return(0); 566 } 567 568 /* 569 * if all we wanted was VA, return now 570 */ 571 572 if (flags & (UVM_KMF_VAONLY | UVM_KMF_PAGEABLE)) { 573 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 574 return(kva); 575 } 576 577 /* 578 * recover object offset from virtual address 579 */ 580 581 offset = kva - vm_map_min(kernel_map); 582 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 583 584 /* 585 * now allocate and map in the memory... note that we are the only ones 586 * whom should ever get a handle on this area of VM. 587 */ 588 589 loopva = kva; 590 loopsize = size; 591 592 pgaflags = 0; 593 if (flags & UVM_KMF_NOWAIT) 594 pgaflags |= UVM_PGA_USERESERVE; 595 if (flags & UVM_KMF_ZERO) 596 pgaflags |= UVM_PGA_ZERO; 597 prot = VM_PROT_READ | VM_PROT_WRITE; 598 if (flags & UVM_KMF_EXEC) 599 prot |= VM_PROT_EXECUTE; 600 while (loopsize) { 601 KASSERT(!pmap_extract(pmap_kernel(), loopva, NULL)); 602 603 pg = uvm_pagealloc(NULL, offset, NULL, pgaflags); 604 605 /* 606 * out of memory? 607 */ 608 609 if (__predict_false(pg == NULL)) { 610 if ((flags & UVM_KMF_NOWAIT) || 611 ((flags & UVM_KMF_CANFAIL) && !uvm_reclaimable())) { 612 /* free everything! */ 613 uvm_km_free(map, kva, size, 614 flags & UVM_KMF_TYPEMASK); 615 return (0); 616 } else { 617 uvm_wait("km_getwait2"); /* sleep here */ 618 continue; 619 } 620 } 621 622 pg->flags &= ~PG_BUSY; /* new page */ 623 UVM_PAGE_OWN(pg, NULL); 624 625 /* 626 * map it in 627 */ 628 629 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), 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