uvm_km.c revision 1.67
1/* $NetBSD: uvm_km.c,v 1.67 2004/01/29 12:06:02 yamt 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 1.67 2004/01/29 12:06:02 yamt 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; 158static struct vm_map_entry kernel_first_mapent_store; 159 160/* 161 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 162 * KVM already allocated for text, data, bss, and static data structures). 163 * 164 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 165 * we assume that [min -> start] has already been allocated and that 166 * "end" is the end. 167 */ 168 169void 170uvm_km_init(start, end) 171 vaddr_t start, end; 172{ 173 vaddr_t base = VM_MIN_KERNEL_ADDRESS; 174 175 /* 176 * next, init kernel memory objects. 177 */ 178 179 /* kernel_object: for pageable anonymous kernel memory */ 180 uao_init(); 181 uvm.kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 182 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 183 184 /* 185 * init the map and reserve any space that might already 186 * have been allocated kernel space before installing. 187 */ 188 189 uvm_map_setup(&kernel_map_store, base, end, VM_MAP_PAGEABLE); 190 kernel_map_store.pmap = pmap_kernel(); 191 if (start != base) { 192 int error; 193 struct uvm_map_args args; 194 195 error = uvm_map_prepare(&kernel_map_store, base, start - base, 196 NULL, UVM_UNKNOWN_OFFSET, 0, 197 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 198 UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args); 199 if (!error) { 200 struct vm_map_entry *entry = &kernel_first_mapent_store; 201 202 kernel_first_mapent_store.flags = 203 UVM_MAP_KERNEL | UVM_MAP_FIRST; 204 error = uvm_map_enter(&kernel_map_store, &args, &entry); 205 KASSERT(entry == NULL); 206 } 207 208 if (error) 209 panic( 210 "uvm_km_init: could not reserve space for kernel"); 211 } 212 213 /* 214 * install! 215 */ 216 217 kernel_map = &kernel_map_store; 218} 219 220/* 221 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 222 * is allocated all references to that area of VM must go through it. this 223 * allows the locking of VAs in kernel_map to be broken up into regions. 224 * 225 * => if `fixed' is true, *min specifies where the region described 226 * by the submap must start 227 * => if submap is non NULL we use that as the submap, otherwise we 228 * alloc a new map 229 */ 230struct vm_map * 231uvm_km_suballoc(map, min, max, size, flags, fixed, submap) 232 struct vm_map *map; 233 vaddr_t *min, *max; /* IN/OUT, OUT */ 234 vsize_t size; 235 int flags; 236 boolean_t fixed; 237 struct vm_map *submap; 238{ 239 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 240 241 size = round_page(size); /* round up to pagesize */ 242 243 /* 244 * first allocate a blank spot in the parent map 245 */ 246 247 if (uvm_map(map, min, size, NULL, UVM_UNKNOWN_OFFSET, 0, 248 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 249 UVM_ADV_RANDOM, mapflags)) != 0) { 250 panic("uvm_km_suballoc: unable to allocate space in parent map"); 251 } 252 253 /* 254 * set VM bounds (min is filled in by uvm_map) 255 */ 256 257 *max = *min + size; 258 259 /* 260 * add references to pmap and create or init the submap 261 */ 262 263 pmap_reference(vm_map_pmap(map)); 264 if (submap == NULL) { 265 submap = uvm_map_create(vm_map_pmap(map), *min, *max, flags); 266 if (submap == NULL) 267 panic("uvm_km_suballoc: unable to create submap"); 268 } else { 269 uvm_map_setup(submap, *min, *max, flags); 270 submap->pmap = vm_map_pmap(map); 271 } 272 273 /* 274 * now let uvm_map_submap plug in it... 275 */ 276 277 if (uvm_map_submap(map, *min, *max, submap) != 0) 278 panic("uvm_km_suballoc: submap allocation failed"); 279 280 return(submap); 281} 282 283/* 284 * uvm_km_pgremove: remove pages from a kernel uvm_object. 285 * 286 * => when you unmap a part of anonymous kernel memory you want to toss 287 * the pages right away. (this gets called from uvm_unmap_...). 288 */ 289 290void 291uvm_km_pgremove(uobj, start, end) 292 struct uvm_object *uobj; 293 vaddr_t start, end; 294{ 295 struct vm_page *pg; 296 voff_t curoff, nextoff; 297 int swpgonlydelta = 0; 298 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 299 300 KASSERT(uobj->pgops == &aobj_pager); 301 simple_lock(&uobj->vmobjlock); 302 303 for (curoff = start; curoff < end; curoff = nextoff) { 304 nextoff = curoff + PAGE_SIZE; 305 pg = uvm_pagelookup(uobj, curoff); 306 if (pg != NULL && pg->flags & PG_BUSY) { 307 pg->flags |= PG_WANTED; 308 UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0, 309 "km_pgrm", 0); 310 simple_lock(&uobj->vmobjlock); 311 nextoff = curoff; 312 continue; 313 } 314 315 /* 316 * free the swap slot, then the page. 317 */ 318 319 if (pg == NULL && 320 uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) { 321 swpgonlydelta++; 322 } 323 uao_dropswap(uobj, curoff >> PAGE_SHIFT); 324 if (pg != NULL) { 325 uvm_lock_pageq(); 326 uvm_pagefree(pg); 327 uvm_unlock_pageq(); 328 } 329 } 330 simple_unlock(&uobj->vmobjlock); 331 332 if (swpgonlydelta > 0) { 333 simple_lock(&uvm.swap_data_lock); 334 KASSERT(uvmexp.swpgonly >= swpgonlydelta); 335 uvmexp.swpgonly -= swpgonlydelta; 336 simple_unlock(&uvm.swap_data_lock); 337 } 338} 339 340 341/* 342 * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for "intrsafe" 343 * maps 344 * 345 * => when you unmap a part of anonymous kernel memory you want to toss 346 * the pages right away. (this is called from uvm_unmap_...). 347 * => none of the pages will ever be busy, and none of them will ever 348 * be on the active or inactive queues (because they have no object). 349 */ 350 351void 352uvm_km_pgremove_intrsafe(start, end) 353 vaddr_t start, end; 354{ 355 struct vm_page *pg; 356 paddr_t pa; 357 UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist); 358 359 for (; start < end; start += PAGE_SIZE) { 360 if (!pmap_extract(pmap_kernel(), start, &pa)) { 361 continue; 362 } 363 pg = PHYS_TO_VM_PAGE(pa); 364 KASSERT(pg); 365 KASSERT(pg->uobject == NULL && pg->uanon == NULL); 366 uvm_pagefree(pg); 367 } 368} 369 370 371/* 372 * uvm_km_kmemalloc: lower level kernel memory allocator for malloc() 373 * 374 * => we map wired memory into the specified map using the obj passed in 375 * => NOTE: we can return NULL even if we can wait if there is not enough 376 * free VM space in the map... caller should be prepared to handle 377 * this case. 378 * => we return KVA of memory allocated 379 * => align,prefer - passed on to uvm_map() 380 * => flags: NOWAIT, VALLOC - just allocate VA, TRYLOCK - fail if we can't 381 * lock the map 382 */ 383 384vaddr_t 385uvm_km_kmemalloc1(map, obj, size, align, prefer, flags) 386 struct vm_map *map; 387 struct uvm_object *obj; 388 vsize_t size; 389 vsize_t align; 390 voff_t prefer; 391 int flags; 392{ 393 vaddr_t kva, loopva; 394 vaddr_t offset; 395 vsize_t loopsize; 396 struct vm_page *pg; 397 UVMHIST_FUNC("uvm_km_kmemalloc"); UVMHIST_CALLED(maphist); 398 399 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 400 map, obj, size, flags); 401 KASSERT(vm_map_pmap(map) == pmap_kernel()); 402 403 /* 404 * setup for call 405 */ 406 407 size = round_page(size); 408 kva = vm_map_min(map); /* hint */ 409 410 /* 411 * allocate some virtual space 412 */ 413 414 if (__predict_false(uvm_map(map, &kva, size, obj, prefer, align, 415 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 416 UVM_ADV_RANDOM, 417 (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT)))) 418 != 0)) { 419 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 420 return(0); 421 } 422 423 /* 424 * if all we wanted was VA, return now 425 */ 426 427 if (flags & UVM_KMF_VALLOC) { 428 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 429 return(kva); 430 } 431 432 /* 433 * recover object offset from virtual address 434 */ 435 436 offset = kva - vm_map_min(kernel_map); 437 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 438 439 /* 440 * now allocate and map in the memory... note that we are the only ones 441 * whom should ever get a handle on this area of VM. 442 */ 443 444 loopva = kva; 445 loopsize = size; 446 while (loopsize) { 447 if (obj) { 448 simple_lock(&obj->vmobjlock); 449 } 450 pg = uvm_pagealloc(obj, offset, NULL, UVM_PGA_USERESERVE); 451 if (__predict_true(pg != NULL)) { 452 pg->flags &= ~PG_BUSY; /* new page */ 453 UVM_PAGE_OWN(pg, NULL); 454 } 455 if (obj) { 456 simple_unlock(&obj->vmobjlock); 457 } 458 459 /* 460 * out of memory? 461 */ 462 463 if (__predict_false(pg == NULL)) { 464 if ((flags & UVM_KMF_NOWAIT) || 465 ((flags & UVM_KMF_CANFAIL) && uvm_swapisfull())) { 466 /* free everything! */ 467 uvm_unmap(map, kva, kva + size); 468 return (0); 469 } else { 470 uvm_wait("km_getwait2"); /* sleep here */ 471 continue; 472 } 473 } 474 475 /* 476 * map it in 477 */ 478 479 if (obj == NULL) { 480 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), 481 VM_PROT_READ | VM_PROT_WRITE); 482 } else { 483 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 484 UVM_PROT_ALL, 485 PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 486 } 487 loopva += PAGE_SIZE; 488 offset += PAGE_SIZE; 489 loopsize -= PAGE_SIZE; 490 } 491 492 pmap_update(pmap_kernel()); 493 494 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 495 return(kva); 496} 497 498/* 499 * uvm_km_free: free an area of kernel memory 500 */ 501 502void 503uvm_km_free(map, addr, size) 504 struct vm_map *map; 505 vaddr_t addr; 506 vsize_t size; 507{ 508 uvm_unmap(map, trunc_page(addr), round_page(addr+size)); 509} 510 511/* 512 * uvm_km_free_wakeup: free an area of kernel memory and wake up 513 * anyone waiting for vm space. 514 * 515 * => XXX: "wanted" bit + unlock&wait on other end? 516 */ 517 518void 519uvm_km_free_wakeup(map, addr, size) 520 struct vm_map *map; 521 vaddr_t addr; 522 vsize_t size; 523{ 524 struct vm_map_entry *dead_entries; 525 526 vm_map_lock(map); 527 uvm_unmap_remove(map, trunc_page(addr), round_page(addr + size), 528 &dead_entries); 529 wakeup(map); 530 vm_map_unlock(map); 531 if (dead_entries != NULL) 532 uvm_unmap_detach(dead_entries, 0); 533} 534 535/* 536 * uvm_km_alloc1: allocate wired down memory in the kernel map. 537 * 538 * => we can sleep if needed 539 */ 540 541vaddr_t 542uvm_km_alloc1(map, size, zeroit) 543 struct vm_map *map; 544 vsize_t size; 545 boolean_t zeroit; 546{ 547 vaddr_t kva, loopva, offset; 548 struct vm_page *pg; 549 UVMHIST_FUNC("uvm_km_alloc1"); UVMHIST_CALLED(maphist); 550 551 UVMHIST_LOG(maphist,"(map=0x%x, size=0x%x)", map, size,0,0); 552 KASSERT(vm_map_pmap(map) == pmap_kernel()); 553 554 size = round_page(size); 555 kva = vm_map_min(map); /* hint */ 556 557 /* 558 * allocate some virtual space 559 */ 560 561 if (__predict_false(uvm_map(map, &kva, size, uvm.kernel_object, 562 UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, 563 UVM_INH_NONE, UVM_ADV_RANDOM, 564 0)) != 0)) { 565 UVMHIST_LOG(maphist,"<- done (no VM)",0,0,0,0); 566 return(0); 567 } 568 569 /* 570 * recover object offset from virtual address 571 */ 572 573 offset = kva - vm_map_min(kernel_map); 574 UVMHIST_LOG(maphist," kva=0x%x, offset=0x%x", kva, offset,0,0); 575 576 /* 577 * now allocate the memory. 578 */ 579 580 loopva = kva; 581 while (size) { 582 simple_lock(&uvm.kernel_object->vmobjlock); 583 KASSERT(uvm_pagelookup(uvm.kernel_object, offset) == NULL); 584 pg = uvm_pagealloc(uvm.kernel_object, offset, NULL, 0); 585 if (pg) { 586 pg->flags &= ~PG_BUSY; 587 UVM_PAGE_OWN(pg, NULL); 588 } 589 simple_unlock(&uvm.kernel_object->vmobjlock); 590 if (pg == NULL) { 591 uvm_wait("km_alloc1w"); 592 continue; 593 } 594 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 595 UVM_PROT_ALL, PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE); 596 loopva += PAGE_SIZE; 597 offset += PAGE_SIZE; 598 size -= PAGE_SIZE; 599 } 600 pmap_update(map->pmap); 601 602 /* 603 * zero on request (note that "size" is now zero due to the above loop 604 * so we need to subtract kva from loopva to reconstruct the size). 605 */ 606 607 if (zeroit) 608 memset((caddr_t)kva, 0, loopva - kva); 609 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 610 return(kva); 611} 612 613/* 614 * uvm_km_valloc1: allocate zero-fill memory in the kernel's address space 615 * 616 * => memory is not allocated until fault time 617 * => the align, prefer and flags parameters are passed on to uvm_map(). 618 * 619 * Note: this function is also the backend for these macros: 620 * uvm_km_valloc 621 * uvm_km_valloc_wait 622 * uvm_km_valloc_prefer 623 * uvm_km_valloc_prefer_wait 624 * uvm_km_valloc_align 625 */ 626 627vaddr_t 628uvm_km_valloc1(map, size, align, prefer, flags) 629 struct vm_map *map; 630 vsize_t size; 631 vsize_t align; 632 voff_t prefer; 633 uvm_flag_t flags; 634{ 635 vaddr_t kva; 636 UVMHIST_FUNC("uvm_km_valloc1"); UVMHIST_CALLED(maphist); 637 638 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x, align=0x%x, prefer=0x%x)", 639 map, size, align, prefer); 640 641 KASSERT(vm_map_pmap(map) == pmap_kernel()); 642 643 size = round_page(size); 644 /* 645 * Check if requested size is larger than the map, in which 646 * case we can't succeed. 647 */ 648 if (size > vm_map_max(map) - vm_map_min(map)) 649 return (0); 650 651 for (;;) { 652 kva = vm_map_min(map); /* hint */ 653 654 /* 655 * allocate some virtual space. will be demand filled 656 * by kernel_object. 657 */ 658 659 if (__predict_true(uvm_map(map, &kva, size, uvm.kernel_object, 660 prefer, align, UVM_MAPFLAG(UVM_PROT_ALL, 661 UVM_PROT_ALL, UVM_INH_NONE, UVM_ADV_RANDOM, flags)) 662 == 0)) { 663 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 664 return (kva); 665 } 666 667 /* 668 * failed. sleep for a while (on map) 669 */ 670 if ((flags & UVM_KMF_NOWAIT) != 0) 671 return (0); 672 673 UVMHIST_LOG(maphist,"<<<sleeping>>>",0,0,0,0); 674 tsleep((caddr_t)map, PVM, "vallocwait", 0); 675 } 676 /*NOTREACHED*/ 677} 678 679/* Function definitions for binary compatibility */ 680vaddr_t 681uvm_km_kmemalloc(struct vm_map *map, struct uvm_object *obj, 682 vsize_t sz, int flags) 683{ 684 return uvm_km_kmemalloc1(map, obj, sz, 0, UVM_UNKNOWN_OFFSET, flags); 685} 686 687vaddr_t uvm_km_valloc(struct vm_map *map, vsize_t sz) 688{ 689 return uvm_km_valloc1(map, sz, 0, UVM_UNKNOWN_OFFSET, UVM_KMF_NOWAIT); 690} 691 692vaddr_t uvm_km_valloc_align(struct vm_map *map, vsize_t sz, vsize_t align) 693{ 694 return uvm_km_valloc1(map, sz, align, UVM_UNKNOWN_OFFSET, UVM_KMF_NOWAIT); 695} 696 697vaddr_t uvm_km_valloc_prefer_wait(struct vm_map *map, vsize_t sz, voff_t prefer) 698{ 699 return uvm_km_valloc1(map, sz, 0, prefer, 0); 700} 701 702vaddr_t uvm_km_valloc_wait(struct vm_map *map, vsize_t sz) 703{ 704 return uvm_km_valloc1(map, sz, 0, UVM_UNKNOWN_OFFSET, 0); 705} 706 707/* Sanity; must specify both or none. */ 708#if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 709 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 710#error Must specify MAP and UNMAP together. 711#endif 712 713/* 714 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 715 * 716 * => if the pmap specifies an alternate mapping method, we use it. 717 */ 718 719/* ARGSUSED */ 720vaddr_t 721uvm_km_alloc_poolpage1(map, obj, waitok) 722 struct vm_map *map; 723 struct uvm_object *obj; 724 boolean_t waitok; 725{ 726#if defined(PMAP_MAP_POOLPAGE) 727 struct vm_page *pg; 728 vaddr_t va; 729 730 again: 731 pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE); 732 if (__predict_false(pg == NULL)) { 733 if (waitok) { 734 uvm_wait("plpg"); 735 goto again; 736 } else 737 return (0); 738 } 739 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 740 if (__predict_false(va == 0)) 741 uvm_pagefree(pg); 742 return (va); 743#else 744 vaddr_t va; 745 int s; 746 747 /* 748 * NOTE: We may be called with a map that doens't require splvm 749 * protection (e.g. kernel_map). However, it does not hurt to 750 * go to splvm in this case (since unprocted maps will never be 751 * accessed in interrupt context). 752 * 753 * XXX We may want to consider changing the interface to this 754 * XXX function. 755 */ 756 757 s = splvm(); 758 va = uvm_km_kmemalloc(map, obj, PAGE_SIZE, 759 waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK); 760 splx(s); 761 return (va); 762#endif /* PMAP_MAP_POOLPAGE */ 763} 764 765/* 766 * uvm_km_free_poolpage: free a previously allocated pool page 767 * 768 * => if the pmap specifies an alternate unmapping method, we use it. 769 */ 770 771/* ARGSUSED */ 772void 773uvm_km_free_poolpage1(map, addr) 774 struct vm_map *map; 775 vaddr_t addr; 776{ 777#if defined(PMAP_UNMAP_POOLPAGE) 778 paddr_t pa; 779 780 pa = PMAP_UNMAP_POOLPAGE(addr); 781 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 782#else 783 int s; 784 785 /* 786 * NOTE: We may be called with a map that doens't require splvm 787 * protection (e.g. kernel_map). However, it does not hurt to 788 * go to splvm in this case (since unprocted maps will never be 789 * accessed in interrupt context). 790 * 791 * XXX We may want to consider changing the interface to this 792 * XXX function. 793 */ 794 795 s = splvm(); 796 uvm_km_free(map, addr, PAGE_SIZE); 797 splx(s); 798#endif /* PMAP_UNMAP_POOLPAGE */ 799} 800