uvm_km.c revision 1.64
1/* $NetBSD: uvm_km.c,v 1.64 2003/08/28 13:12:18 pk 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. *** access to kmem_map must be protected 94 * by splvm() because we are allowed to call malloc() 95 * at interrupt time *** 96 * mb_map => memory for large mbufs, *** protected by splvm *** 97 * pager_map => used to map "buf" structures into kernel space 98 * exec_map => used during exec to handle exec args 99 * etc... 100 * 101 * the kernel allocates its private memory out of special uvm_objects whose 102 * reference count is set to UVM_OBJ_KERN (thus indicating that the objects 103 * are "special" and never die). all kernel objects should be thought of 104 * as large, fixed-sized, sparsely populated uvm_objects. each kernel 105 * object is equal to the size of kernel virtual address space (i.e. the 106 * value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS"). 107 * 108 * most kernel private memory lives in kernel_object. the only exception 109 * to this is for memory that belongs to submaps that must be protected 110 * by splvm(). pages in these submaps are not assigned to an object. 111 * 112 * note that just because a kernel object spans the entire kernel virutal 113 * address space doesn't mean that it has to be mapped into the entire space. 114 * large chunks of a kernel object's space go unused either because 115 * that area of kernel VM is unmapped, or there is some other type of 116 * object mapped into that range (e.g. a vnode). for submap's kernel 117 * objects, the only part of the object that can ever be populated is the 118 * offsets that are managed by the submap. 119 * 120 * note that the "offset" in a kernel object is always the kernel virtual 121 * address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)). 122 * example: 123 * suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a 124 * uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the 125 * kernel map]. if uvm_km_alloc returns virtual address 0xf8235000, 126 * then that means that the page at offset 0x235000 in kernel_object is 127 * mapped at 0xf8235000. 128 * 129 * kernel object have one other special property: when the kernel virtual 130 * memory mapping them is unmapped, the backing memory in the object is 131 * freed right away. this is done with the uvm_km_pgremove() function. 132 * this has to be done because there is no backing store for kernel pages 133 * and no need to save them after they are no longer referenced. 134 */ 135 136#include <sys/cdefs.h> 137__KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.64 2003/08/28 13:12:18 pk Exp $"); 138 139#include "opt_uvmhist.h" 140 141#include <sys/param.h> 142#include <sys/systm.h> 143#include <sys/proc.h> 144 145#include <uvm/uvm.h> 146 147/* 148 * global data structures 149 */ 150 151struct vm_map *kernel_map = NULL; 152 153/* 154 * local data structues 155 */ 156 157static struct vm_map kernel_map_store; 158 159/* 160 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 161 * KVM already allocated for text, data, bss, and static data structures). 162 * 163 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 164 * we assume that [min -> start] has already been allocated and that 165 * "end" is the end. 166 */ 167 168void 169uvm_km_init(start, end) 170 vaddr_t start, end; 171{ 172 vaddr_t base = VM_MIN_KERNEL_ADDRESS; 173 174 /* 175 * next, init kernel memory objects. 176 */ 177 178 /* kernel_object: for pageable anonymous kernel memory */ 179 uao_init(); 180 uvm.kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 181 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 182 183 /* 184 * init the map and reserve any space that might already 185 * have been allocated kernel space before installing. 186 */ 187 188 uvm_map_setup(&kernel_map_store, base, end, VM_MAP_PAGEABLE); 189 kernel_map_store.pmap = pmap_kernel(); 190 if (start != base && 191 uvm_map(&kernel_map_store, &base, start - base, NULL, 192 UVM_UNKNOWN_OFFSET, 0, 193 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 194 UVM_ADV_RANDOM, UVM_FLAG_FIXED)) != 0) 195 panic("uvm_km_init: could not reserve space for kernel"); 196 197 /* 198 * install! 199 */ 200 201 kernel_map = &kernel_map_store; 202} 203 204/* 205 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 206 * is allocated all references to that area of VM must go through it. this 207 * allows the locking of VAs in kernel_map to be broken up into regions. 208 * 209 * => if `fixed' is true, *min specifies where the region described 210 * by the submap must start 211 * => if submap is non NULL we use that as the submap, otherwise we 212 * alloc a new map 213 */ 214struct vm_map * 215uvm_km_suballoc(map, min, max, size, flags, fixed, submap) 216 struct vm_map *map; 217 vaddr_t *min, *max; /* IN/OUT, OUT */ 218 vsize_t size; 219 int flags; 220 boolean_t fixed; 221 struct vm_map *submap; 222{ 223 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 224 225 size = round_page(size); /* round up to pagesize */ 226 227 /* 228 * first allocate a blank spot in the parent map 229 */ 230 231 if (uvm_map(map, min, size, NULL, UVM_UNKNOWN_OFFSET, 0, 232 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 233 UVM_ADV_RANDOM, mapflags)) != 0) { 234 panic("uvm_km_suballoc: unable to allocate space in parent map"); 235 } 236 237 /* 238 * set VM bounds (min is filled in by uvm_map) 239 */ 240 241 *max = *min + size; 242 243 /* 244 * add references to pmap and create or init the submap 245 */ 246 247 pmap_reference(vm_map_pmap(map)); 248 if (submap == NULL) { 249 submap = uvm_map_create(vm_map_pmap(map), *min, *max, flags); 250 if (submap == NULL) 251 panic("uvm_km_suballoc: unable to create submap"); 252 } else { 253 uvm_map_setup(submap, *min, *max, flags); 254 submap->pmap = vm_map_pmap(map); 255 } 256 257 /* 258 * now let uvm_map_submap plug in it... 259 */ 260 261 if (uvm_map_submap(map, *min, *max, submap) != 0) 262 panic("uvm_km_suballoc: submap allocation failed"); 263 264 return(submap); 265} 266 267/* 268 * uvm_km_pgremove: remove pages from a kernel uvm_object. 269 * 270 * => when you unmap a part of anonymous kernel memory you want to toss 271 * the pages right away. (this gets called from uvm_unmap_...). 272 */ 273 274void 275uvm_km_pgremove(uobj, start, end) 276 struct uvm_object *uobj; 277 vaddr_t start, end; 278{ 279 struct vm_page *pg; 280 voff_t curoff, nextoff; 281 int swpgonlydelta = 0; 282 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 283 284 KASSERT(uobj->pgops == &aobj_pager); 285 simple_lock(&uobj->vmobjlock); 286 287 for (curoff = start; curoff < end; curoff = nextoff) { 288 nextoff = curoff + PAGE_SIZE; 289 pg = uvm_pagelookup(uobj, curoff); 290 if (pg != NULL && pg->flags & PG_BUSY) { 291 pg->flags |= PG_WANTED; 292 UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, 293 "km_pgrm", 0); 294 simple_lock(&uobj->vmobjlock); 295 nextoff = curoff; 296 continue; 297 } 298 299 /* 300 * free the swap slot, then the page. 301 */ 302 303 if (pg == NULL && 304 uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) { 305 swpgonlydelta++; 306 } 307 uao_dropswap(uobj, curoff >> PAGE_SHIFT); 308 if (pg != NULL) { 309 uvm_lock_pageq(); 310 uvm_pagefree(pg); 311 uvm_unlock_pageq(); 312 } 313 } 314 simple_unlock(&uobj->vmobjlock); 315 316 if (swpgonlydelta > 0) { 317 simple_lock(&uvm.swap_data_lock); 318 KASSERT(uvmexp.swpgonly >= swpgonlydelta); 319 uvmexp.swpgonly -= swpgonlydelta; 320 simple_unlock(&uvm.swap_data_lock); 321 } 322} 323 324 325/* 326 * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for "intrsafe" 327 * maps 328 * 329 * => when you unmap a part of anonymous kernel memory you want to toss 330 * the pages right away. (this is called from uvm_unmap_...). 331 * => none of the pages will ever be busy, and none of them will ever 332 * be on the active or inactive queues (because they have no object). 333 */ 334 335void 336uvm_km_pgremove_intrsafe(start, end) 337 vaddr_t start, end; 338{ 339 struct vm_page *pg; 340 paddr_t pa; 341 UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist); 342 343 for (; start < end; start += PAGE_SIZE) { 344 if (!pmap_extract(pmap_kernel(), start, &pa)) { 345 continue; 346 } 347 pg = PHYS_TO_VM_PAGE(pa); 348 KASSERT(pg); 349 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 350 uvm_pagefree(pg); 351 } 352} 353 354 355/* 356 * uvm_km_kmemalloc: lower level kernel memory allocator for malloc() 357 * 358 * => we map wired memory into the specified map using the obj passed in 359 * => NOTE: we can return NULL even if we can wait if there is not enough 360 * free VM space in the map... caller should be prepared to handle 361 * this case. 362 * => we return KVA of memory allocated 363 * => flags: NOWAIT, VALLOC - just allocate VA, TRYLOCK - fail if we can't 364 * lock the map 365 */ 366 367vaddr_t 368uvm_km_kmemalloc(map, obj, size, flags) 369 struct vm_map *map; 370 struct uvm_object *obj; 371 vsize_t size; 372 int flags; 373{ 374 vaddr_t kva, loopva; 375 vaddr_t offset; 376 vsize_t loopsize; 377 struct vm_page *pg; 378 UVMHIST_FUNC("uvm_km_kmemalloc"); UVMHIST_CALLED(maphist); 379 380 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 381 map, obj, size, flags); 382 KASSERT(vm_map_pmap(map) == pmap_kernel()); 383 384 /* 385 * setup for call 386 */ 387 388 size = round_page(size); 389 kva = vm_map_min(map); /* hint */ 390 391 /* 392 * allocate some virtual space 393 */ 394 395 if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 396 0, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 397 UVM_ADV_RANDOM, 398 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT)))) 399 != 0)) { 400 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 401 return(0); 402 } 403 404 /* 405 * if all we wanted was VA, return now 406 */ 407 408 if (flags & UVM_KMF_VALLOC) { 409 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 410 return(kva); 411 } 412 413 /* 414 * recover object offset from virtual address 415 */ 416 417 offset = kva - vm_map_min(kernel_map); 418 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 419 420 /* 421 * now allocate and map in the memory... note that we are the only ones 422 * whom should ever get a handle on this area of VM. 423 */ 424 425 loopva = kva; 426 loopsize = size; 427 while (loopsize) { 428 if (obj) { 429 simple_lock(&obj->vmobjlock); 430 } 431 pg = uvm_pagealloc(obj, offset, NULL, UVM_PGA_USERESERVE); 432 if (__predict_true(pg != NULL)) { 433 pg->flags &= ~PG_BUSY; /* new page */ 434 UVM_PAGE_OWN(pg, NULL); 435 } 436 if (obj) { 437 simple_unlock(&obj->vmobjlock); 438 } 439 440 /* 441 * out of memory? 442 */ 443 444 if (__predict_false(pg == NULL)) { 445 if ((flags & UVM_KMF_NOWAIT) || 446 ((flags & UVM_KMF_CANFAIL) && uvm_swapisfull())) { 447 /* free everything! */ 448 uvm_unmap(map, kva, kva + size); 449 return (0); 450 } else { 451 uvm_wait("km_getwait2"); /* sleep here */ 452 continue; 453 } 454 } 455 456 /* 457 * map it in 458 */ 459 460 if (obj == NULL) { 461 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), 462 VM_PROT_READ | VM_PROT_WRITE); 463 } else { 464 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 465 UVM_PROT_ALL, 466 PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 467 } 468 loopva += PAGE_SIZE; 469 offset += PAGE_SIZE; 470 loopsize -= PAGE_SIZE; 471 } 472 473 pmap_update(pmap_kernel()); 474 475 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 476 return(kva); 477} 478 479/* 480 * uvm_km_free: free an area of kernel memory 481 */ 482 483void 484uvm_km_free(map, addr, size) 485 struct vm_map *map; 486 vaddr_t addr; 487 vsize_t size; 488{ 489 uvm_unmap(map, trunc_page(addr), round_page(addr+size)); 490} 491 492/* 493 * uvm_km_free_wakeup: free an area of kernel memory and wake up 494 * anyone waiting for vm space. 495 * 496 * => XXX: "wanted" bit + unlock&wait on other end? 497 */ 498 499void 500uvm_km_free_wakeup(map, addr, size) 501 struct vm_map *map; 502 vaddr_t addr; 503 vsize_t size; 504{ 505 struct vm_map_entry *dead_entries; 506 507 vm_map_lock(map); 508 uvm_unmap_remove(map, trunc_page(addr), round_page(addr + size), 509 &dead_entries); 510 wakeup(map); 511 vm_map_unlock(map); 512 if (dead_entries != NULL) 513 uvm_unmap_detach(dead_entries, 0); 514} 515 516/* 517 * uvm_km_alloc1: allocate wired down memory in the kernel map. 518 * 519 * => we can sleep if needed 520 */ 521 522vaddr_t 523uvm_km_alloc1(map, size, zeroit) 524 struct vm_map *map; 525 vsize_t size; 526 boolean_t zeroit; 527{ 528 vaddr_t kva, loopva, offset; 529 struct vm_page *pg; 530 UVMHIST_FUNC("uvm_km_alloc1"); UVMHIST_CALLED(maphist); 531 532 UVMHIST_LOG(maphist,"(map=0x%x, size=0x%x)", map, size,0,0); 533 KASSERT(vm_map_pmap(map) == pmap_kernel()); 534 535 size = round_page(size); 536 kva = vm_map_min(map); /* hint */ 537 538 /* 539 * allocate some virtual space 540 */ 541 542 if (__predict_false(uvm_map(map, &kva, size, uvm.kernel_object, 543 UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, 544 UVM_INH_NONE, UVM_ADV_RANDOM, 545 0)) != 0)) { 546 UVMHIST_LOG(maphist,"<- done (no VM)",0,0,0,0); 547 return(0); 548 } 549 550 /* 551 * recover object offset from virtual address 552 */ 553 554 offset = kva - vm_map_min(kernel_map); 555 UVMHIST_LOG(maphist," kva=0x%x, offset=0x%x", kva, offset,0,0); 556 557 /* 558 * now allocate the memory. 559 */ 560 561 loopva = kva; 562 while (size) { 563 simple_lock(&uvm.kernel_object->vmobjlock); 564 KASSERT(uvm_pagelookup(uvm.kernel_object, offset) == NULL); 565 pg = uvm_pagealloc(uvm.kernel_object, offset, NULL, 0); 566 if (pg) { 567 pg->flags &= ~PG_BUSY; 568 UVM_PAGE_OWN(pg, NULL); 569 } 570 simple_unlock(&uvm.kernel_object->vmobjlock); 571 if (pg == NULL) { 572 uvm_wait("km_alloc1w"); 573 continue; 574 } 575 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 576 UVM_PROT_ALL, PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 577 loopva += PAGE_SIZE; 578 offset += PAGE_SIZE; 579 size -= PAGE_SIZE; 580 } 581 pmap_update(map->pmap); 582 583 /* 584 * zero on request (note that "size" is now zero due to the above loop 585 * so we need to subtract kva from loopva to reconstruct the size). 586 */ 587 588 if (zeroit) 589 memset((caddr_t)kva, 0, loopva - kva); 590 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 591 return(kva); 592} 593 594/* 595 * uvm_km_valloc: allocate zero-fill memory in the kernel's address space 596 * 597 * => memory is not allocated until fault time 598 */ 599 600vaddr_t 601uvm_km_valloc(map, size) 602 struct vm_map *map; 603 vsize_t size; 604{ 605 return(uvm_km_valloc_align(map, size, 0)); 606} 607 608vaddr_t 609uvm_km_valloc_align(map, size, align) 610 struct vm_map *map; 611 vsize_t size; 612 vsize_t align; 613{ 614 vaddr_t kva; 615 UVMHIST_FUNC("uvm_km_valloc"); UVMHIST_CALLED(maphist); 616 617 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x)", map, size, 0,0); 618 KASSERT(vm_map_pmap(map) == pmap_kernel()); 619 620 size = round_page(size); 621 kva = vm_map_min(map); /* hint */ 622 623 /* 624 * allocate some virtual space. will be demand filled by kernel_object. 625 */ 626 627 if (__predict_false(uvm_map(map, &kva, size, uvm.kernel_object, 628 UVM_UNKNOWN_OFFSET, align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, 629 UVM_INH_NONE, UVM_ADV_RANDOM, 630 0)) != 0)) { 631 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 632 return(0); 633 } 634 635 UVMHIST_LOG(maphist, "<- done (kva=0x%x)", kva,0,0,0); 636 return(kva); 637} 638 639/* 640 * uvm_km_valloc_wait: allocate zero-fill memory in the kernel's address space 641 * 642 * => memory is not allocated until fault time 643 * => if no room in map, wait for space to free, unless requested size 644 * is larger than map (in which case we return 0) 645 */ 646 647vaddr_t 648uvm_km_valloc_prefer_wait(map, size, prefer) 649 struct vm_map *map; 650 vsize_t size; 651 voff_t prefer; 652{ 653 vaddr_t kva; 654 UVMHIST_FUNC("uvm_km_valloc_prefer_wait"); UVMHIST_CALLED(maphist); 655 656 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x)", map, size, 0,0); 657 KASSERT(vm_map_pmap(map) == pmap_kernel()); 658 659 size = round_page(size); 660 if (size > vm_map_max(map) - vm_map_min(map)) 661 return(0); 662 663 for (;;) { 664 kva = vm_map_min(map); /* hint */ 665 666 /* 667 * allocate some virtual space. will be demand filled 668 * by kernel_object. 669 */ 670 671 if (__predict_true(uvm_map(map, &kva, size, uvm.kernel_object, 672 prefer, 0, UVM_MAPFLAG(UVM_PROT_ALL, 673 UVM_PROT_ALL, UVM_INH_NONE, UVM_ADV_RANDOM, 0)) 674 == 0)) { 675 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 676 return(kva); 677 } 678 679 /* 680 * failed. sleep for a while (on map) 681 */ 682 683 UVMHIST_LOG(maphist,"<<<sleeping>>>",0,0,0,0); 684 tsleep((caddr_t)map, PVM, "vallocwait", 0); 685 } 686 /*NOTREACHED*/ 687} 688 689vaddr_t 690uvm_km_valloc_wait(map, size) 691 struct vm_map *map; 692 vsize_t size; 693{ 694 return uvm_km_valloc_prefer_wait(map, size, UVM_UNKNOWN_OFFSET); 695} 696 697/* Sanity; must specify both or none. */ 698#if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 699 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 700#error Must specify MAP and UNMAP together. 701#endif 702 703/* 704 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 705 * 706 * => if the pmap specifies an alternate mapping method, we use it. 707 */ 708 709/* ARGSUSED */ 710vaddr_t 711uvm_km_alloc_poolpage1(map, obj, waitok) 712 struct vm_map *map; 713 struct uvm_object *obj; 714 boolean_t waitok; 715{ 716#if defined(PMAP_MAP_POOLPAGE) 717 struct vm_page *pg; 718 vaddr_t va; 719 720 again: 721 pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE); 722 if (__predict_false(pg == NULL)) { 723 if (waitok) { 724 uvm_wait("plpg"); 725 goto again; 726 } else 727 return (0); 728 } 729 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 730 if (__predict_false(va == 0)) 731 uvm_pagefree(pg); 732 return (va); 733#else 734 vaddr_t va; 735 int s; 736 737 /* 738 * NOTE: We may be called with a map that doens't require splvm 739 * protection (e.g. kernel_map). However, it does not hurt to 740 * go to splvm in this case (since unprocted maps will never be 741 * accessed in interrupt context). 742 * 743 * XXX We may want to consider changing the interface to this 744 * XXX function. 745 */ 746 747 s = splvm(); 748 va = uvm_km_kmemalloc(map, obj, PAGE_SIZE, 749 waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK); 750 splx(s); 751 return (va); 752#endif /* PMAP_MAP_POOLPAGE */ 753} 754 755/* 756 * uvm_km_free_poolpage: free a previously allocated pool page 757 * 758 * => if the pmap specifies an alternate unmapping method, we use it. 759 */ 760 761/* ARGSUSED */ 762void 763uvm_km_free_poolpage1(map, addr) 764 struct vm_map *map; 765 vaddr_t addr; 766{ 767#if defined(PMAP_UNMAP_POOLPAGE) 768 paddr_t pa; 769 770 pa = PMAP_UNMAP_POOLPAGE(addr); 771 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 772#else 773 int s; 774 775 /* 776 * NOTE: We may be called with a map that doens't require splvm 777 * protection (e.g. kernel_map). However, it does not hurt to 778 * go to splvm in this case (since unprocted maps will never be 779 * accessed in interrupt context). 780 * 781 * XXX We may want to consider changing the interface to this 782 * XXX function. 783 */ 784 785 s = splvm(); 786 uvm_km_free(map, addr, PAGE_SIZE); 787 splx(s); 788#endif /* PMAP_UNMAP_POOLPAGE */ 789} 790