uvm_km.c revision 1.12
1/* $NetBSD: uvm_km.c,v 1.12 1998/08/01 01:39:03 thorpej Exp $ */ 2 3/* 4 * XXXCDC: "ROUGH DRAFT" QUALITY UVM PRE-RELEASE FILE! 5 * >>>USE AT YOUR OWN RISK, WORK IS NOT FINISHED<<< 6 */ 7/* 8 * Copyright (c) 1997 Charles D. Cranor and Washington University. 9 * Copyright (c) 1991, 1993, The Regents of the University of California. 10 * 11 * All rights reserved. 12 * 13 * This code is derived from software contributed to Berkeley by 14 * The Mach Operating System project at Carnegie-Mellon University. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. All advertising materials mentioning features or use of this software 25 * must display the following acknowledgement: 26 * This product includes software developed by Charles D. Cranor, 27 * Washington University, the University of California, Berkeley and 28 * its contributors. 29 * 4. Neither the name of the University nor the names of its contributors 30 * may be used to endorse or promote products derived from this software 31 * without specific prior written permission. 32 * 33 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 36 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 43 * SUCH DAMAGE. 44 * 45 * @(#)vm_kern.c 8.3 (Berkeley) 1/12/94 46 * from: Id: uvm_km.c,v 1.1.2.14 1998/02/06 05:19:27 chs Exp 47 * 48 * 49 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 50 * All rights reserved. 51 * 52 * Permission to use, copy, modify and distribute this software and 53 * its documentation is hereby granted, provided that both the copyright 54 * notice and this permission notice appear in all copies of the 55 * software, derivative works or modified versions, and any portions 56 * thereof, and that both notices appear in supporting documentation. 57 * 58 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 59 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 60 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 61 * 62 * Carnegie Mellon requests users of this software to return to 63 * 64 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 65 * School of Computer Science 66 * Carnegie Mellon University 67 * Pittsburgh PA 15213-3890 68 * 69 * any improvements or extensions that they make and grant Carnegie the 70 * rights to redistribute these changes. 71 */ 72 73#include "opt_uvmhist.h" 74#include "opt_pmap_new.h" 75 76/* 77 * uvm_km.c: handle kernel memory allocation and management 78 */ 79 80/* 81 * overview of kernel memory management: 82 * 83 * the kernel virtual address space is mapped by "kernel_map." kernel_map 84 * starts at VM_MIN_KERNEL_ADDRESS and goes to VM_MAX_KERNEL_ADDRESS. 85 * note that VM_MIN_KERNEL_ADDRESS is equal to vm_map_min(kernel_map). 86 * 87 * the kernel_map has several "submaps." submaps can only appear in 88 * the kernel_map (user processes can't use them). submaps "take over" 89 * the management of a sub-range of the kernel's address space. submaps 90 * are typically allocated at boot time and are never released. kernel 91 * virtual address space that is mapped by a submap is locked by the 92 * submap's lock -- not the kernel_map's lock. 93 * 94 * thus, the useful feature of submaps is that they allow us to break 95 * up the locking and protection of the kernel address space into smaller 96 * chunks. 97 * 98 * the vm system has several standard kernel submaps, including: 99 * kmem_map => contains only wired kernel memory for the kernel 100 * malloc. *** access to kmem_map must be protected 101 * by splimp() because we are allowed to call malloc() 102 * at interrupt time *** 103 * mb_map => memory for large mbufs, *** protected by splimp *** 104 * pager_map => used to map "buf" structures into kernel space 105 * exec_map => used during exec to handle exec args 106 * etc... 107 * 108 * the kernel allocates its private memory out of special uvm_objects whose 109 * reference count is set to UVM_OBJ_KERN (thus indicating that the objects 110 * are "special" and never die). all kernel objects should be thought of 111 * as large, fixed-sized, sparsely populated uvm_objects. each kernel 112 * object is equal to the size of kernel virtual address space (i.e. the 113 * value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS"). 114 * 115 * most kernel private memory lives in kernel_object. the only exception 116 * to this is for memory that belongs to submaps that must be protected 117 * by splimp(). each of these submaps has their own private kernel 118 * object (e.g. kmem_object, mb_object). 119 * 120 * note that just because a kernel object spans the entire kernel virutal 121 * address space doesn't mean that it has to be mapped into the entire space. 122 * large chunks of a kernel object's space go unused either because 123 * that area of kernel VM is unmapped, or there is some other type of 124 * object mapped into that range (e.g. a vnode). for submap's kernel 125 * objects, the only part of the object that can ever be populated is the 126 * offsets that are managed by the submap. 127 * 128 * note that the "offset" in a kernel object is always the kernel virtual 129 * address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)). 130 * example: 131 * suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a 132 * uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the 133 * kernel map]. if uvm_km_alloc returns virtual address 0xf8235000, 134 * then that means that the page at offset 0x235000 in kernel_object is 135 * mapped at 0xf8235000. 136 * 137 * note that the offsets in kmem_object and mb_object also follow this 138 * rule. this means that the offsets for kmem_object must fall in the 139 * range of [vm_map_min(kmem_object) - vm_map_min(kernel_map)] to 140 * [vm_map_max(kmem_object) - vm_map_min(kernel_map)], so the offsets 141 * in those objects will typically not start at zero. 142 * 143 * kernel object have one other special property: when the kernel virtual 144 * memory mapping them is unmapped, the backing memory in the object is 145 * freed right away. this is done with the uvm_km_pgremove() function. 146 * this has to be done because there is no backing store for kernel pages 147 * and no need to save them after they are no longer referenced. 148 */ 149 150#include <sys/param.h> 151#include <sys/systm.h> 152#include <sys/proc.h> 153 154#include <vm/vm.h> 155#include <vm/vm_page.h> 156#include <vm/vm_kern.h> 157 158#include <uvm/uvm.h> 159 160/* 161 * global data structures 162 */ 163 164vm_map_t kernel_map = NULL; 165 166/* 167 * local functions 168 */ 169 170static int uvm_km_get __P((struct uvm_object *, vm_offset_t, 171 vm_page_t *, int *, int, vm_prot_t, int, int)); 172/* 173 * local data structues 174 */ 175 176static struct vm_map kernel_map_store; 177static struct uvm_object kmem_object_store; 178static struct uvm_object mb_object_store; 179 180static struct uvm_pagerops km_pager = { 181 NULL, /* init */ 182 NULL, /* attach */ 183 NULL, /* reference */ 184 NULL, /* detach */ 185 NULL, /* fault */ 186 NULL, /* flush */ 187 uvm_km_get, /* get */ 188 /* ... rest are NULL */ 189}; 190 191/* 192 * uvm_km_get: pager get function for kernel objects 193 * 194 * => currently we do not support pageout to the swap area, so this 195 * pager is very simple. eventually we may want an anonymous 196 * object pager which will do paging. 197 * => XXXCDC: this pager should be phased out in favor of the aobj pager 198 */ 199 200 201static int 202uvm_km_get(uobj, offset, pps, npagesp, centeridx, access_type, advice, flags) 203 struct uvm_object *uobj; 204 vm_offset_t offset; 205 struct vm_page **pps; 206 int *npagesp; 207 int centeridx, advice, flags; 208 vm_prot_t access_type; 209{ 210 vm_offset_t current_offset; 211 vm_page_t ptmp; 212 int lcv, gotpages, maxpages; 213 boolean_t done; 214 UVMHIST_FUNC("uvm_km_get"); UVMHIST_CALLED(maphist); 215 216 UVMHIST_LOG(maphist, "flags=%d", flags,0,0,0); 217 218 /* 219 * get number of pages 220 */ 221 222 maxpages = *npagesp; 223 224 /* 225 * step 1: handled the case where fault data structures are locked. 226 */ 227 228 if (flags & PGO_LOCKED) { 229 230 /* 231 * step 1a: get pages that are already resident. only do 232 * this if the data structures are locked (i.e. the first time 233 * through). 234 */ 235 236 done = TRUE; /* be optimistic */ 237 gotpages = 0; /* # of pages we got so far */ 238 239 for (lcv = 0, current_offset = offset ; 240 lcv < maxpages ; lcv++, current_offset += PAGE_SIZE) { 241 242 /* do we care about this page? if not, skip it */ 243 if (pps[lcv] == PGO_DONTCARE) 244 continue; 245 246 /* lookup page */ 247 ptmp = uvm_pagelookup(uobj, current_offset); 248 249 /* null? attempt to allocate the page */ 250 if (ptmp == NULL) { 251 ptmp = uvm_pagealloc(uobj, current_offset, 252 NULL); 253 if (ptmp) { 254 /* new page */ 255 ptmp->flags &= ~(PG_BUSY|PG_FAKE); 256 UVM_PAGE_OWN(ptmp, NULL); 257 uvm_pagezero(ptmp); 258 } 259 } 260 261 /* 262 * to be useful must get a non-busy, non-released page 263 */ 264 if (ptmp == NULL || 265 (ptmp->flags & (PG_BUSY|PG_RELEASED)) != 0) { 266 if (lcv == centeridx || 267 (flags & PGO_ALLPAGES) != 0) 268 /* need to do a wait or I/O! */ 269 done = FALSE; 270 continue; 271 } 272 273 /* 274 * useful page: busy/lock it and plug it in our 275 * result array 276 */ 277 278 /* caller must un-busy this page */ 279 ptmp->flags |= PG_BUSY; 280 UVM_PAGE_OWN(ptmp, "uvm_km_get1"); 281 pps[lcv] = ptmp; 282 gotpages++; 283 284 } /* "for" lcv loop */ 285 286 /* 287 * step 1b: now we've either done everything needed or we 288 * to unlock and do some waiting or I/O. 289 */ 290 291 UVMHIST_LOG(maphist, "<- done (done=%d)", done, 0,0,0); 292 293 *npagesp = gotpages; 294 if (done) 295 return(VM_PAGER_OK); /* bingo! */ 296 else 297 return(VM_PAGER_UNLOCK); /* EEK! Need to 298 * unlock and I/O */ 299 } 300 301 /* 302 * step 2: get non-resident or busy pages. 303 * object is locked. data structures are unlocked. 304 */ 305 306 for (lcv = 0, current_offset = offset ; 307 lcv < maxpages ; lcv++, current_offset += PAGE_SIZE) { 308 309 /* skip over pages we've already gotten or don't want */ 310 /* skip over pages we don't _have_ to get */ 311 if (pps[lcv] != NULL || 312 (lcv != centeridx && (flags & PGO_ALLPAGES) == 0)) 313 continue; 314 315 /* 316 * we have yet to locate the current page (pps[lcv]). we 317 * first look for a page that is already at the current offset. 318 * if we find a page, we check to see if it is busy or 319 * released. if that is the case, then we sleep on the page 320 * until it is no longer busy or released and repeat the 321 * lookup. if the page we found is neither busy nor 322 * released, then we busy it (so we own it) and plug it into 323 * pps[lcv]. this 'break's the following while loop and 324 * indicates we are ready to move on to the next page in the 325 * "lcv" loop above. 326 * 327 * if we exit the while loop with pps[lcv] still set to NULL, 328 * then it means that we allocated a new busy/fake/clean page 329 * ptmp in the object and we need to do I/O to fill in the 330 * data. 331 */ 332 333 while (pps[lcv] == NULL) { /* top of "pps" while loop */ 334 335 /* look for a current page */ 336 ptmp = uvm_pagelookup(uobj, current_offset); 337 338 /* nope? allocate one now (if we can) */ 339 if (ptmp == NULL) { 340 341 ptmp = uvm_pagealloc(uobj, current_offset, 342 NULL); /* alloc */ 343 344 /* out of RAM? */ 345 if (ptmp == NULL) { 346 simple_unlock(&uobj->vmobjlock); 347 uvm_wait("kmgetwait1"); 348 simple_lock(&uobj->vmobjlock); 349 /* goto top of pps while loop */ 350 continue; 351 } 352 353 /* 354 * got new page ready for I/O. break pps 355 * while loop. pps[lcv] is still NULL. 356 */ 357 break; 358 } 359 360 /* page is there, see if we need to wait on it */ 361 if ((ptmp->flags & (PG_BUSY|PG_RELEASED)) != 0) { 362 ptmp->flags |= PG_WANTED; 363 UVM_UNLOCK_AND_WAIT(ptmp,&uobj->vmobjlock, 0, 364 "uvn_get",0); 365 simple_lock(&uobj->vmobjlock); 366 continue; /* goto top of pps while loop */ 367 } 368 369 /* 370 * if we get here then the page has become resident 371 * and unbusy between steps 1 and 2. we busy it now 372 * (so we own it) and set pps[lcv] (so that we exit 373 * the while loop). caller must un-busy. 374 */ 375 ptmp->flags |= PG_BUSY; 376 UVM_PAGE_OWN(ptmp, "uvm_km_get2"); 377 pps[lcv] = ptmp; 378 } 379 380 /* 381 * if we own the a valid page at the correct offset, pps[lcv] 382 * will point to it. nothing more to do except go to the 383 * next page. 384 */ 385 386 if (pps[lcv]) 387 continue; /* next lcv */ 388 389 /* 390 * we have a "fake/busy/clean" page that we just allocated. 391 * do the needed "i/o" (in this case that means zero it). 392 */ 393 394 uvm_pagezero(ptmp); 395 ptmp->flags &= ~(PG_FAKE); 396 pps[lcv] = ptmp; 397 398 } /* lcv loop */ 399 400 /* 401 * finally, unlock object and return. 402 */ 403 404 simple_unlock(&uobj->vmobjlock); 405 UVMHIST_LOG(maphist, "<- done (OK)",0,0,0,0); 406 return(VM_PAGER_OK); 407} 408 409/* 410 * uvm_km_init: init kernel maps and objects to reflect reality (i.e. 411 * KVM already allocated for text, data, bss, and static data structures). 412 * 413 * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS. 414 * we assume that [min -> start] has already been allocated and that 415 * "end" is the end. 416 */ 417 418void 419uvm_km_init(start, end) 420 vm_offset_t start, end; 421{ 422 vm_offset_t base = VM_MIN_KERNEL_ADDRESS; 423 424 /* 425 * first, init kernel memory objects. 426 */ 427 428 /* kernel_object: for pageable anonymous kernel memory */ 429 uvm.kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS - 430 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ); 431 432 /* kmem_object: for malloc'd memory (wired, protected by splimp) */ 433 simple_lock_init(&kmem_object_store.vmobjlock); 434 kmem_object_store.pgops = &km_pager; 435 TAILQ_INIT(&kmem_object_store.memq); 436 kmem_object_store.uo_npages = 0; 437 /* we are special. we never die */ 438 kmem_object_store.uo_refs = UVM_OBJ_KERN; 439 uvmexp.kmem_object = &kmem_object_store; 440 441 /* mb_object: for mbuf memory (always wired, protected by splimp) */ 442 simple_lock_init(&mb_object_store.vmobjlock); 443 mb_object_store.pgops = &km_pager; 444 TAILQ_INIT(&mb_object_store.memq); 445 mb_object_store.uo_npages = 0; 446 /* we are special. we never die */ 447 mb_object_store.uo_refs = UVM_OBJ_KERN; 448 uvmexp.mb_object = &mb_object_store; 449 450 /* 451 * init the map and reserve allready allocated kernel space 452 * before installing. 453 */ 454 455 uvm_map_setup(&kernel_map_store, base, end, FALSE); 456 kernel_map_store.pmap = pmap_kernel(); 457 if (uvm_map(&kernel_map_store, &base, start - base, NULL, 458 UVM_UNKNOWN_OFFSET, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, 459 UVM_INH_NONE, UVM_ADV_RANDOM,UVM_FLAG_FIXED)) != KERN_SUCCESS) 460 panic("uvm_km_init: could not reserve space for kernel"); 461 462 /* 463 * install! 464 */ 465 466 kernel_map = &kernel_map_store; 467} 468 469/* 470 * uvm_km_suballoc: allocate a submap in the kernel map. once a submap 471 * is allocated all references to that area of VM must go through it. this 472 * allows the locking of VAs in kernel_map to be broken up into regions. 473 * 474 * => if `fixed' is true, *min specifies where the region described 475 * by the submap must start 476 * => if submap is non NULL we use that as the submap, otherwise we 477 * alloc a new map 478 */ 479struct vm_map * 480uvm_km_suballoc(map, min, max, size, pageable, fixed, submap) 481 struct vm_map *map; 482 vm_offset_t *min, *max; /* OUT, OUT */ 483 vm_size_t size; 484 boolean_t pageable; 485 boolean_t fixed; 486 struct vm_map *submap; 487{ 488 int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0); 489 490 size = round_page(size); /* round up to pagesize */ 491 492 /* 493 * first allocate a blank spot in the parent map 494 */ 495 496 if (uvm_map(map, min, size, NULL, UVM_UNKNOWN_OFFSET, 497 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 498 UVM_ADV_RANDOM, mapflags)) != KERN_SUCCESS) { 499 panic("uvm_km_suballoc: unable to allocate space in parent map"); 500 } 501 502 /* 503 * set VM bounds (min is filled in by uvm_map) 504 */ 505 506 *max = *min + size; 507 508 /* 509 * add references to pmap and create or init the submap 510 */ 511 512 pmap_reference(vm_map_pmap(map)); 513 if (submap == NULL) { 514 submap = uvm_map_create(vm_map_pmap(map), *min, *max, pageable); 515 if (submap == NULL) 516 panic("uvm_km_suballoc: unable to create submap"); 517 } else { 518 uvm_map_setup(submap, *min, *max, pageable); 519 submap->pmap = vm_map_pmap(map); 520 } 521 522 /* 523 * now let uvm_map_submap plug in it... 524 */ 525 526 if (uvm_map_submap(map, *min, *max, submap) != KERN_SUCCESS) 527 panic("uvm_km_suballoc: submap allocation failed"); 528 529 return(submap); 530} 531 532/* 533 * uvm_km_pgremove: remove pages from a kernel uvm_object. 534 * 535 * => when you unmap a part of anonymous kernel memory you want to toss 536 * the pages right away. (this gets called from uvm_unmap_...). 537 */ 538 539#define UKM_HASH_PENALTY 4 /* a guess */ 540 541void 542uvm_km_pgremove(uobj, start, end) 543 struct uvm_object *uobj; 544 vm_offset_t start, end; 545{ 546 boolean_t by_list, is_aobj; 547 struct vm_page *pp, *ppnext; 548 vm_offset_t curoff; 549 UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist); 550 551 simple_lock(&uobj->vmobjlock); /* lock object */ 552 553 /* is uobj an aobj? */ 554 is_aobj = uobj->pgops == &aobj_pager; 555 556 /* choose cheapest traversal */ 557 by_list = (uobj->uo_npages <= 558 ((end - start) / PAGE_SIZE) * UKM_HASH_PENALTY); 559 560 if (by_list) 561 goto loop_by_list; 562 563 /* by hash */ 564 565 for (curoff = start ; curoff < end ; curoff += PAGE_SIZE) { 566 pp = uvm_pagelookup(uobj, curoff); 567 if (pp == NULL) 568 continue; 569 570 UVMHIST_LOG(maphist," page 0x%x, busy=%d", pp, 571 pp->flags & PG_BUSY, 0, 0); 572 /* now do the actual work */ 573 if (pp->flags & PG_BUSY) 574 /* owner must check for this when done */ 575 pp->flags |= PG_RELEASED; 576 else { 577 pmap_page_protect(PMAP_PGARG(pp), VM_PROT_NONE); 578 579 /* 580 * if this kernel object is an aobj, free the swap slot. 581 */ 582 if (is_aobj) { 583 int slot = uao_set_swslot(uobj, 584 curoff / PAGE_SIZE, 0); 585 586 if (slot) 587 uvm_swap_free(slot, 1); 588 } 589 590 uvm_lock_pageq(); 591 uvm_pagefree(pp); 592 uvm_unlock_pageq(); 593 } 594 /* done */ 595 596 } 597 simple_unlock(&uobj->vmobjlock); 598 return; 599 600loop_by_list: 601 602 for (pp = uobj->memq.tqh_first ; pp != NULL ; pp = ppnext) { 603 604 ppnext = pp->listq.tqe_next; 605 if (pp->offset < start || pp->offset >= end) { 606 continue; 607 } 608 609 UVMHIST_LOG(maphist," page 0x%x, busy=%d", pp, 610 pp->flags & PG_BUSY, 0, 0); 611 /* now do the actual work */ 612 if (pp->flags & PG_BUSY) 613 /* owner must check for this when done */ 614 pp->flags |= PG_RELEASED; 615 else { 616 pmap_page_protect(PMAP_PGARG(pp), VM_PROT_NONE); 617 618 /* 619 * if this kernel object is an aobj, free the swap slot. 620 */ 621 if (is_aobj) { 622 int slot = uao_set_swslot(uobj, 623 pp->offset / PAGE_SIZE, 0); 624 625 if (slot) 626 uvm_swap_free(slot, 1); 627 } 628 629 uvm_lock_pageq(); 630 uvm_pagefree(pp); 631 uvm_unlock_pageq(); 632 } 633 /* done */ 634 635 } 636 simple_unlock(&uobj->vmobjlock); 637 return; 638} 639 640 641/* 642 * uvm_km_kmemalloc: lower level kernel memory allocator for malloc() 643 * 644 * => we map wired memory into the specified map using the obj passed in 645 * => NOTE: we can return NULL even if we can wait if there is not enough 646 * free VM space in the map... caller should be prepared to handle 647 * this case. 648 * => we return KVA of memory allocated 649 * => flags: NOWAIT, VALLOC - just allocate VA, TRYLOCK - fail if we can't 650 * lock the map 651 */ 652 653vm_offset_t 654uvm_km_kmemalloc(map, obj, size, flags) 655 vm_map_t map; 656 struct uvm_object *obj; 657 vm_size_t size; 658 int flags; 659{ 660 vm_offset_t kva, loopva; 661 vm_offset_t offset; 662 struct vm_page *pg; 663 UVMHIST_FUNC("uvm_km_kmemalloc"); UVMHIST_CALLED(maphist); 664 665 666 UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)", 667 map, obj, size, flags); 668#ifdef DIAGNOSTIC 669 /* sanity check */ 670 if (vm_map_pmap(map) != pmap_kernel()) 671 panic("uvm_km_kmemalloc: invalid map"); 672#endif 673 674 /* 675 * setup for call 676 */ 677 678 size = round_page(size); 679 kva = vm_map_min(map); /* hint */ 680 681 /* 682 * allocate some virtual space 683 */ 684 685 if (uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET, 686 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 687 UVM_ADV_RANDOM, (flags & UVM_KMF_TRYLOCK))) 688 != KERN_SUCCESS) { 689 UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0); 690 return(0); 691 } 692 693 /* 694 * if all we wanted was VA, return now 695 */ 696 697 if (flags & UVM_KMF_VALLOC) { 698 UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0); 699 return(kva); 700 } 701 /* 702 * recover object offset from virtual address 703 */ 704 705 offset = kva - vm_map_min(kernel_map); 706 UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0); 707 708 /* 709 * now allocate and map in the memory... note that we are the only ones 710 * whom should ever get a handle on this area of VM. 711 */ 712 713 loopva = kva; 714 while (size) { 715 simple_lock(&obj->vmobjlock); 716 pg = uvm_pagealloc(obj, offset, NULL); 717 if (pg) { 718 pg->flags &= ~PG_BUSY; /* new page */ 719 UVM_PAGE_OWN(pg, NULL); 720 } 721 simple_unlock(&obj->vmobjlock); 722 723 /* 724 * out of memory? 725 */ 726 727 if (pg == NULL) { 728 if (flags & UVM_KMF_NOWAIT) { 729 /* free everything! */ 730 uvm_unmap(map, kva, kva + size, 0); 731 return(0); 732 } else { 733 uvm_wait("km_getwait2"); /* sleep here */ 734 continue; 735 } 736 } 737 738 /* 739 * map it in: note that we call pmap_enter with the map and 740 * object unlocked in case we are kmem_map/kmem_object 741 * (because if pmap_enter wants to allocate out of kmem_object 742 * it will need to lock it itself!) 743 */ 744#if defined(PMAP_NEW) 745 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), VM_PROT_ALL); 746#else 747 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 748 UVM_PROT_ALL, TRUE); 749#endif 750 loopva += PAGE_SIZE; 751 offset += PAGE_SIZE; 752 size -= PAGE_SIZE; 753 } 754 755 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 756 return(kva); 757} 758 759/* 760 * uvm_km_free: free an area of kernel memory 761 */ 762 763void 764uvm_km_free(map, addr, size) 765 vm_map_t map; 766 vm_offset_t addr; 767 vm_size_t size; 768{ 769 770 uvm_unmap(map, trunc_page(addr), round_page(addr+size), 1); 771} 772 773/* 774 * uvm_km_free_wakeup: free an area of kernel memory and wake up 775 * anyone waiting for vm space. 776 * 777 * => XXX: "wanted" bit + unlock&wait on other end? 778 */ 779 780void 781uvm_km_free_wakeup(map, addr, size) 782 vm_map_t map; 783 vm_offset_t addr; 784 vm_size_t size; 785{ 786 vm_map_entry_t dead_entries; 787 788 vm_map_lock(map); 789 (void)uvm_unmap_remove(map, trunc_page(addr), round_page(addr+size), 1, 790 &dead_entries); 791 thread_wakeup(map); 792 vm_map_unlock(map); 793 794 if (dead_entries != NULL) 795 uvm_unmap_detach(dead_entries, 0); 796} 797 798/* 799 * uvm_km_alloc1: allocate wired down memory in the kernel map. 800 * 801 * => we can sleep if needed 802 */ 803 804vm_offset_t 805uvm_km_alloc1(map, size, zeroit) 806 vm_map_t map; 807 vm_size_t size; 808 boolean_t zeroit; 809{ 810 vm_offset_t kva, loopva, offset; 811 struct vm_page *pg; 812 UVMHIST_FUNC("uvm_km_alloc1"); UVMHIST_CALLED(maphist); 813 814 UVMHIST_LOG(maphist,"(map=0x%x, size=0x%x)", map, size,0,0); 815 816#ifdef DIAGNOSTIC 817 if (vm_map_pmap(map) != pmap_kernel()) 818 panic("uvm_km_alloc1"); 819#endif 820 821 size = round_page(size); 822 kva = vm_map_min(map); /* hint */ 823 824 /* 825 * allocate some virtual space 826 */ 827 828 if (uvm_map(map, &kva, size, uvm.kernel_object, UVM_UNKNOWN_OFFSET, 829 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 830 UVM_ADV_RANDOM, 0)) != KERN_SUCCESS) { 831 UVMHIST_LOG(maphist,"<- done (no VM)",0,0,0,0); 832 return(0); 833 } 834 835 /* 836 * recover object offset from virtual address 837 */ 838 839 offset = kva - vm_map_min(kernel_map); 840 UVMHIST_LOG(maphist," kva=0x%x, offset=0x%x", kva, offset,0,0); 841 842 /* 843 * now allocate the memory. we must be careful about released pages. 844 */ 845 846 loopva = kva; 847 while (size) { 848 simple_lock(&uvm.kernel_object->vmobjlock); 849 pg = uvm_pagelookup(uvm.kernel_object, offset); 850 851 /* 852 * if we found a page in an unallocated region, it must be 853 * released 854 */ 855 if (pg) { 856 if ((pg->flags & PG_RELEASED) == 0) 857 panic("uvm_km_alloc1: non-released page"); 858 pg->flags |= PG_WANTED; 859 UVM_UNLOCK_AND_WAIT(pg, &uvm.kernel_object->vmobjlock, 860 0, "km_alloc", 0); 861 continue; /* retry */ 862 } 863 864 /* allocate ram */ 865 pg = uvm_pagealloc(uvm.kernel_object, offset, NULL); 866 if (pg) { 867 pg->flags &= ~PG_BUSY; /* new page */ 868 UVM_PAGE_OWN(pg, NULL); 869 } 870 simple_unlock(&uvm.kernel_object->vmobjlock); 871 if (pg == NULL) { 872 uvm_wait("km_alloc1w"); /* wait for memory */ 873 continue; 874 } 875 876 /* map it in */ 877#if defined(PMAP_NEW) 878 pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg), UVM_PROT_ALL); 879#else 880 pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg), 881 UVM_PROT_ALL, TRUE); 882#endif 883 loopva += PAGE_SIZE; 884 offset += PAGE_SIZE; 885 size -= PAGE_SIZE; 886 } 887 888 /* 889 * zero on request (note that "size" is now zero due to the above loop 890 * so we need to subtract kva from loopva to reconstruct the size). 891 */ 892 893 if (zeroit) 894 bzero((caddr_t)kva, loopva - kva); 895 896 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 897 return(kva); 898} 899 900/* 901 * uvm_km_valloc: allocate zero-fill memory in the kernel's address space 902 * 903 * => memory is not allocated until fault time 904 */ 905 906vm_offset_t 907uvm_km_valloc(map, size) 908 vm_map_t map; 909 vm_size_t size; 910{ 911 vm_offset_t kva; 912 UVMHIST_FUNC("uvm_km_valloc"); UVMHIST_CALLED(maphist); 913 914 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x)", map, size, 0,0); 915 916#ifdef DIAGNOSTIC 917 if (vm_map_pmap(map) != pmap_kernel()) 918 panic("uvm_km_valloc"); 919#endif 920 921 size = round_page(size); 922 kva = vm_map_min(map); /* hint */ 923 924 /* 925 * allocate some virtual space. will be demand filled by kernel_object. 926 */ 927 928 if (uvm_map(map, &kva, size, uvm.kernel_object, UVM_UNKNOWN_OFFSET, 929 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE, 930 UVM_ADV_RANDOM, 0)) != KERN_SUCCESS) { 931 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 932 return(0); 933 } 934 935 UVMHIST_LOG(maphist, "<- done (kva=0x%x)", kva,0,0,0); 936 return(kva); 937} 938 939/* 940 * uvm_km_valloc_wait: allocate zero-fill memory in the kernel's address space 941 * 942 * => memory is not allocated until fault time 943 * => if no room in map, wait for space to free, unless requested size 944 * is larger than map (in which case we return 0) 945 */ 946 947vm_offset_t 948uvm_km_valloc_wait(map, size) 949 vm_map_t map; 950 vm_size_t size; 951{ 952 vm_offset_t kva; 953 UVMHIST_FUNC("uvm_km_valloc_wait"); UVMHIST_CALLED(maphist); 954 955 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x)", map, size, 0,0); 956 957#ifdef DIAGNOSTIC 958 if (vm_map_pmap(map) != pmap_kernel()) 959 panic("uvm_km_valloc_wait"); 960#endif 961 962 size = round_page(size); 963 if (size > vm_map_max(map) - vm_map_min(map)) 964 return(0); 965 966 while (1) { 967 kva = vm_map_min(map); /* hint */ 968 969 /* 970 * allocate some virtual space. will be demand filled 971 * by kernel_object. 972 */ 973 974 if (uvm_map(map, &kva, size, uvm.kernel_object, 975 UVM_UNKNOWN_OFFSET, UVM_MAPFLAG(UVM_PROT_ALL, 976 UVM_PROT_ALL, UVM_INH_NONE, UVM_ADV_RANDOM, 0)) 977 == KERN_SUCCESS) { 978 UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0); 979 return(kva); 980 } 981 982 /* 983 * failed. sleep for a while (on map) 984 */ 985 986 UVMHIST_LOG(maphist,"<<<sleeping>>>",0,0,0,0); 987 tsleep((caddr_t)map, PVM, "vallocwait", 0); 988 } 989 /*NOTREACHED*/ 990} 991 992/* Sanity; must specify both or none. */ 993#if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \ 994 (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE)) 995#error Must specify MAP and UNMAP together. 996#endif 997 998/* 999 * uvm_km_alloc_poolpage: allocate a page for the pool allocator 1000 * 1001 * => if the pmap specifies an alternate mapping method, we use it. 1002 */ 1003 1004/* ARGSUSED */ 1005vm_offset_t 1006uvm_km_alloc_poolpage1(map, obj) 1007 vm_map_t map; 1008 struct uvm_object *obj; 1009{ 1010#if defined(PMAP_MAP_POOLPAGE) 1011 struct vm_page *pg; 1012 vm_offset_t va; 1013 1014 pg = uvm_pagealloc(NULL, 0, NULL); 1015 if (pg == NULL) 1016 return (0); 1017 va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg)); 1018 if (va == 0) 1019 uvm_pagefree(pg); 1020 return (va); 1021#else 1022 vm_offset_t va; 1023 int s; 1024 1025 s = splimp(); 1026 va = uvm_km_kmemalloc(map, obj, PAGE_SIZE, UVM_KMF_NOWAIT); 1027 splx(s); 1028 return (va); 1029#endif /* PMAP_MAP_POOLPAGE */ 1030} 1031 1032/* 1033 * uvm_km_free_poolpage: free a previously allocated pool page 1034 * 1035 * => if the pmap specifies an alternate unmapping method, we use it. 1036 */ 1037 1038/* ARGSUSED */ 1039void 1040uvm_km_free_poolpage1(map, addr) 1041 vm_map_t map; 1042 vm_offset_t addr; 1043{ 1044#if defined(PMAP_UNMAP_POOLPAGE) 1045 vm_offset_t pa; 1046 1047 pa = PMAP_UNMAP_POOLPAGE(addr); 1048 uvm_pagefree(PHYS_TO_VM_PAGE(pa)); 1049#else 1050 int s; 1051 1052 s = splimp(); 1053 uvm_km_free(map, addr, PAGE_SIZE); 1054 splx(s); 1055#endif /* PMAP_UNMAP_POOLPAGE */ 1056} 1057