xref: /netbsd-src/sys/uvm/uvm_km.c (revision 1c9b56c830954ccf3b57004ac65562e3d6afacf6)
1 /*	$NetBSD: uvm_km.c,v 1.76 2005/01/13 11:50:32 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 1.76 2005/01/13 11:50:32 yamt Exp $");
138 
139 #include "opt_uvmhist.h"
140 
141 #include <sys/param.h>
142 #include <sys/malloc.h>
143 #include <sys/systm.h>
144 #include <sys/proc.h>
145 #include <sys/pool.h>
146 
147 #include <uvm/uvm.h>
148 
149 /*
150  * global data structures
151  */
152 
153 struct vm_map *kernel_map = NULL;
154 
155 /*
156  * local data structues
157  */
158 
159 static struct vm_map_kernel	kernel_map_store;
160 static struct vm_map_entry	kernel_first_mapent_store;
161 
162 #if !defined(PMAP_MAP_POOLPAGE)
163 
164 /*
165  * kva cache
166  *
167  * XXX maybe it's better to do this at the uvm_map layer.
168  */
169 
170 #define	KM_VACACHE_SIZE	(32 * PAGE_SIZE) /* XXX tune */
171 
172 static void *km_vacache_alloc(struct pool *, int);
173 static void km_vacache_free(struct pool *, void *);
174 static void km_vacache_init(struct vm_map *, const char *, size_t);
175 
176 /* XXX */
177 #define	KM_VACACHE_POOL_TO_MAP(pp) \
178 	((struct vm_map *)((char *)(pp) - \
179 	    offsetof(struct vm_map_kernel, vmk_vacache)))
180 
181 static void *
182 km_vacache_alloc(struct pool *pp, int flags)
183 {
184 	vaddr_t va;
185 	size_t size;
186 	struct vm_map *map;
187 #if defined(DEBUG)
188 	vaddr_t loopva;
189 #endif
190 	size = pp->pr_alloc->pa_pagesz;
191 
192 	map = KM_VACACHE_POOL_TO_MAP(pp);
193 
194 	va = vm_map_min(map); /* hint */
195 	if (uvm_map(map, &va, size, NULL, UVM_UNKNOWN_OFFSET, size,
196 	    UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
197 	    UVM_ADV_RANDOM, UVM_FLAG_QUANTUM |
198 	    ((flags & PR_WAITOK) ? 0 : UVM_FLAG_TRYLOCK | UVM_FLAG_NOWAIT))))
199 		return NULL;
200 
201 #if defined(DEBUG)
202 	for (loopva = va; loopva < va + size; loopva += PAGE_SIZE) {
203 		if (pmap_extract(pmap_kernel(), loopva, NULL))
204 			panic("km_vacache_free: has mapping");
205 	}
206 #endif
207 
208 	return (void *)va;
209 }
210 
211 static void
212 km_vacache_free(struct pool *pp, void *v)
213 {
214 	vaddr_t va = (vaddr_t)v;
215 	size_t size = pp->pr_alloc->pa_pagesz;
216 	struct vm_map *map;
217 #if defined(DEBUG)
218 	vaddr_t loopva;
219 
220 	for (loopva = va; loopva < va + size; loopva += PAGE_SIZE) {
221 		if (pmap_extract(pmap_kernel(), loopva, NULL))
222 			panic("km_vacache_free: has mapping");
223 	}
224 #endif
225 	map = KM_VACACHE_POOL_TO_MAP(pp);
226 	uvm_unmap1(map, va, va + size, UVM_FLAG_QUANTUM);
227 }
228 
229 /*
230  * km_vacache_init: initialize kva cache.
231  */
232 
233 static void
234 km_vacache_init(struct vm_map *map, const char *name, size_t size)
235 {
236 	struct vm_map_kernel *vmk;
237 	struct pool *pp;
238 	struct pool_allocator *pa;
239 
240 	KASSERT(VM_MAP_IS_KERNEL(map));
241 	KASSERT(size < (vm_map_max(map) - vm_map_min(map)) / 2); /* sanity */
242 
243 	vmk = vm_map_to_kernel(map);
244 	pp = &vmk->vmk_vacache;
245 	pa = &vmk->vmk_vacache_allocator;
246 	memset(pa, 0, sizeof(*pa));
247 	pa->pa_alloc = km_vacache_alloc;
248 	pa->pa_free = km_vacache_free;
249 	pa->pa_pagesz = (unsigned int)size;
250 	pool_init(pp, PAGE_SIZE, 0, 0, PR_NOTOUCH | PR_RECURSIVE, name, pa);
251 
252 	/* XXX for now.. */
253 	pool_sethiwat(pp, 0);
254 }
255 
256 void
257 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size)
258 {
259 
260 	map->flags |= VM_MAP_VACACHE;
261 	if (size == 0)
262 		size = KM_VACACHE_SIZE;
263 	km_vacache_init(map, name, size);
264 }
265 
266 #else /* !defined(PMAP_MAP_POOLPAGE) */
267 
268 void
269 uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size)
270 {
271 
272 	/* nothing */
273 }
274 
275 #endif /* !defined(PMAP_MAP_POOLPAGE) */
276 
277 /*
278  * uvm_km_init: init kernel maps and objects to reflect reality (i.e.
279  * KVM already allocated for text, data, bss, and static data structures).
280  *
281  * => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS.
282  *    we assume that [min -> start] has already been allocated and that
283  *    "end" is the end.
284  */
285 
286 void
287 uvm_km_init(start, end)
288 	vaddr_t start, end;
289 {
290 	vaddr_t base = VM_MIN_KERNEL_ADDRESS;
291 
292 	/*
293 	 * next, init kernel memory objects.
294 	 */
295 
296 	/* kernel_object: for pageable anonymous kernel memory */
297 	uao_init();
298 	uvm.kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS -
299 				 VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ);
300 
301 	/*
302 	 * init the map and reserve any space that might already
303 	 * have been allocated kernel space before installing.
304 	 */
305 
306 	uvm_map_setup_kernel(&kernel_map_store, base, end, VM_MAP_PAGEABLE);
307 	kernel_map_store.vmk_map.pmap = pmap_kernel();
308 	if (start != base) {
309 		int error;
310 		struct uvm_map_args args;
311 
312 		error = uvm_map_prepare(&kernel_map_store.vmk_map,
313 		    base, start - base,
314 		    NULL, UVM_UNKNOWN_OFFSET, 0,
315 		    UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
316 		    		UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args);
317 		if (!error) {
318 			kernel_first_mapent_store.flags =
319 			    UVM_MAP_KERNEL | UVM_MAP_FIRST;
320 			error = uvm_map_enter(&kernel_map_store.vmk_map, &args,
321 			    &kernel_first_mapent_store);
322 		}
323 
324 		if (error)
325 			panic(
326 			    "uvm_km_init: could not reserve space for kernel");
327 	}
328 
329 	/*
330 	 * install!
331 	 */
332 
333 	kernel_map = &kernel_map_store.vmk_map;
334 	uvm_km_vacache_init(kernel_map, "kvakernel", 0);
335 }
336 
337 /*
338  * uvm_km_suballoc: allocate a submap in the kernel map.   once a submap
339  * is allocated all references to that area of VM must go through it.  this
340  * allows the locking of VAs in kernel_map to be broken up into regions.
341  *
342  * => if `fixed' is true, *min specifies where the region described
343  *      by the submap must start
344  * => if submap is non NULL we use that as the submap, otherwise we
345  *	alloc a new map
346  */
347 struct vm_map *
348 uvm_km_suballoc(map, min, max, size, flags, fixed, submap)
349 	struct vm_map *map;
350 	vaddr_t *min, *max;		/* IN/OUT, OUT */
351 	vsize_t size;
352 	int flags;
353 	boolean_t fixed;
354 	struct vm_map_kernel *submap;
355 {
356 	int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0);
357 
358 	KASSERT(vm_map_pmap(map) == pmap_kernel());
359 
360 	size = round_page(size);	/* round up to pagesize */
361 
362 	/*
363 	 * first allocate a blank spot in the parent map
364 	 */
365 
366 	if (uvm_map(map, min, size, NULL, UVM_UNKNOWN_OFFSET, 0,
367 	    UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
368 	    UVM_ADV_RANDOM, mapflags)) != 0) {
369 	       panic("uvm_km_suballoc: unable to allocate space in parent map");
370 	}
371 
372 	/*
373 	 * set VM bounds (min is filled in by uvm_map)
374 	 */
375 
376 	*max = *min + size;
377 
378 	/*
379 	 * add references to pmap and create or init the submap
380 	 */
381 
382 	pmap_reference(vm_map_pmap(map));
383 	if (submap == NULL) {
384 		submap = malloc(sizeof(*submap), M_VMMAP, M_WAITOK);
385 		if (submap == NULL)
386 			panic("uvm_km_suballoc: unable to create submap");
387 	}
388 	uvm_map_setup_kernel(submap, *min, *max, flags);
389 	submap->vmk_map.pmap = vm_map_pmap(map);
390 
391 	/*
392 	 * now let uvm_map_submap plug in it...
393 	 */
394 
395 	if (uvm_map_submap(map, *min, *max, &submap->vmk_map) != 0)
396 		panic("uvm_km_suballoc: submap allocation failed");
397 
398 	return(&submap->vmk_map);
399 }
400 
401 /*
402  * uvm_km_pgremove: remove pages from a kernel uvm_object.
403  *
404  * => when you unmap a part of anonymous kernel memory you want to toss
405  *    the pages right away.    (this gets called from uvm_unmap_...).
406  */
407 
408 void
409 uvm_km_pgremove(uobj, start, end)
410 	struct uvm_object *uobj;
411 	vaddr_t start, end;
412 {
413 	struct vm_page *pg;
414 	voff_t curoff, nextoff;
415 	int swpgonlydelta = 0;
416 	UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist);
417 
418 	KASSERT(uobj->pgops == &aobj_pager);
419 	simple_lock(&uobj->vmobjlock);
420 
421 	for (curoff = start; curoff < end; curoff = nextoff) {
422 		nextoff = curoff + PAGE_SIZE;
423 		pg = uvm_pagelookup(uobj, curoff);
424 		if (pg != NULL && pg->flags & PG_BUSY) {
425 			pg->flags |= PG_WANTED;
426 			UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0,
427 				    "km_pgrm", 0);
428 			simple_lock(&uobj->vmobjlock);
429 			nextoff = curoff;
430 			continue;
431 		}
432 
433 		/*
434 		 * free the swap slot, then the page.
435 		 */
436 
437 		if (pg == NULL &&
438 		    uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) {
439 			swpgonlydelta++;
440 		}
441 		uao_dropswap(uobj, curoff >> PAGE_SHIFT);
442 		if (pg != NULL) {
443 			uvm_lock_pageq();
444 			uvm_pagefree(pg);
445 			uvm_unlock_pageq();
446 		}
447 	}
448 	simple_unlock(&uobj->vmobjlock);
449 
450 	if (swpgonlydelta > 0) {
451 		simple_lock(&uvm.swap_data_lock);
452 		KASSERT(uvmexp.swpgonly >= swpgonlydelta);
453 		uvmexp.swpgonly -= swpgonlydelta;
454 		simple_unlock(&uvm.swap_data_lock);
455 	}
456 }
457 
458 
459 /*
460  * uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for "intrsafe"
461  *    maps
462  *
463  * => when you unmap a part of anonymous kernel memory you want to toss
464  *    the pages right away.    (this is called from uvm_unmap_...).
465  * => none of the pages will ever be busy, and none of them will ever
466  *    be on the active or inactive queues (because they have no object).
467  */
468 
469 void
470 uvm_km_pgremove_intrsafe(start, end)
471 	vaddr_t start, end;
472 {
473 	struct vm_page *pg;
474 	paddr_t pa;
475 	UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist);
476 
477 	for (; start < end; start += PAGE_SIZE) {
478 		if (!pmap_extract(pmap_kernel(), start, &pa)) {
479 			continue;
480 		}
481 		pg = PHYS_TO_VM_PAGE(pa);
482 		KASSERT(pg);
483 		KASSERT(pg->uobject == NULL && pg->uanon == NULL);
484 		uvm_pagefree(pg);
485 	}
486 }
487 
488 
489 /*
490  * uvm_km_kmemalloc: lower level kernel memory allocator for malloc()
491  *
492  * => we map wired memory into the specified map using the obj passed in
493  * => NOTE: we can return NULL even if we can wait if there is not enough
494  *	free VM space in the map... caller should be prepared to handle
495  *	this case.
496  * => we return KVA of memory allocated
497  * => align,prefer - passed on to uvm_map()
498  * => flags: NOWAIT, VALLOC - just allocate VA, TRYLOCK - fail if we can't
499  *	lock the map
500  */
501 
502 vaddr_t
503 uvm_km_kmemalloc1(map, obj, size, align, prefer, flags)
504 	struct vm_map *map;
505 	struct uvm_object *obj;
506 	vsize_t size;
507 	vsize_t align;
508 	voff_t prefer;
509 	int flags;
510 {
511 	vaddr_t kva, loopva;
512 	vaddr_t offset;
513 	vsize_t loopsize;
514 	struct vm_page *pg;
515 	UVMHIST_FUNC("uvm_km_kmemalloc"); UVMHIST_CALLED(maphist);
516 
517 	UVMHIST_LOG(maphist,"  (map=0x%x, obj=0x%x, size=0x%x, flags=%d)",
518 		    map, obj, size, flags);
519 	KASSERT(vm_map_pmap(map) == pmap_kernel());
520 
521 	/*
522 	 * setup for call
523 	 */
524 
525 	size = round_page(size);
526 	kva = vm_map_min(map);	/* hint */
527 
528 	/*
529 	 * allocate some virtual space
530 	 */
531 
532 	if (__predict_false(uvm_map(map, &kva, size, obj, prefer, align,
533 		UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
534 			    UVM_ADV_RANDOM,
535 			    (flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT))
536 			    | UVM_FLAG_QUANTUM))
537 			!= 0)) {
538 		UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0);
539 		return(0);
540 	}
541 
542 	/*
543 	 * if all we wanted was VA, return now
544 	 */
545 
546 	if (flags & UVM_KMF_VALLOC) {
547 		UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0);
548 		return(kva);
549 	}
550 
551 	/*
552 	 * recover object offset from virtual address
553 	 */
554 
555 	offset = kva - vm_map_min(kernel_map);
556 	UVMHIST_LOG(maphist, "  kva=0x%x, offset=0x%x", kva, offset,0,0);
557 
558 	/*
559 	 * now allocate and map in the memory... note that we are the only ones
560 	 * whom should ever get a handle on this area of VM.
561 	 */
562 
563 	loopva = kva;
564 	loopsize = size;
565 	while (loopsize) {
566 		if (obj) {
567 			simple_lock(&obj->vmobjlock);
568 		}
569 		pg = uvm_pagealloc(obj, offset, NULL, UVM_PGA_USERESERVE);
570 		if (__predict_true(pg != NULL)) {
571 			pg->flags &= ~PG_BUSY;	/* new page */
572 			UVM_PAGE_OWN(pg, NULL);
573 		}
574 		if (obj) {
575 			simple_unlock(&obj->vmobjlock);
576 		}
577 
578 		/*
579 		 * out of memory?
580 		 */
581 
582 		if (__predict_false(pg == NULL)) {
583 			if ((flags & UVM_KMF_NOWAIT) ||
584 			    ((flags & UVM_KMF_CANFAIL) && uvm_swapisfull())) {
585 				/* free everything! */
586 				uvm_unmap1(map, kva, kva + size,
587 				    UVM_FLAG_QUANTUM);
588 				return (0);
589 			} else {
590 				uvm_wait("km_getwait2");	/* sleep here */
591 				continue;
592 			}
593 		}
594 
595 		/*
596 		 * map it in
597 		 */
598 
599 		if (obj == NULL) {
600 			pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg),
601 			    VM_PROT_READ | VM_PROT_WRITE);
602 		} else {
603 			pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg),
604 			    UVM_PROT_ALL,
605 			    PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE);
606 		}
607 		loopva += PAGE_SIZE;
608 		offset += PAGE_SIZE;
609 		loopsize -= PAGE_SIZE;
610 	}
611 
612        	pmap_update(pmap_kernel());
613 
614 	UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0);
615 	return(kva);
616 }
617 
618 /*
619  * uvm_km_free: free an area of kernel memory
620  */
621 
622 void
623 uvm_km_free(map, addr, size)
624 	struct vm_map *map;
625 	vaddr_t addr;
626 	vsize_t size;
627 {
628 	uvm_unmap1(map, trunc_page(addr), round_page(addr+size),
629 	    UVM_FLAG_QUANTUM);
630 }
631 
632 /*
633  * uvm_km_alloc1: allocate wired down memory in the kernel map.
634  *
635  * => we can sleep if needed
636  */
637 
638 vaddr_t
639 uvm_km_alloc1(map, size, zeroit)
640 	struct vm_map *map;
641 	vsize_t size;
642 	boolean_t zeroit;
643 {
644 	vaddr_t kva, loopva, offset;
645 	struct vm_page *pg;
646 	UVMHIST_FUNC("uvm_km_alloc1"); UVMHIST_CALLED(maphist);
647 
648 	UVMHIST_LOG(maphist,"(map=0x%x, size=0x%x)", map, size,0,0);
649 	KASSERT(vm_map_pmap(map) == pmap_kernel());
650 
651 	size = round_page(size);
652 	kva = vm_map_min(map);		/* hint */
653 
654 	/*
655 	 * allocate some virtual space
656 	 */
657 
658 	if (__predict_false(uvm_map(map, &kva, size, uvm.kernel_object,
659 	      UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL,
660 					      UVM_INH_NONE, UVM_ADV_RANDOM,
661 					      UVM_FLAG_QUANTUM)) != 0)) {
662 		UVMHIST_LOG(maphist,"<- done (no VM)",0,0,0,0);
663 		return(0);
664 	}
665 
666 	/*
667 	 * recover object offset from virtual address
668 	 */
669 
670 	offset = kva - vm_map_min(kernel_map);
671 	UVMHIST_LOG(maphist,"  kva=0x%x, offset=0x%x", kva, offset,0,0);
672 
673 	/*
674 	 * now allocate the memory.
675 	 */
676 
677 	loopva = kva;
678 	while (size) {
679 		simple_lock(&uvm.kernel_object->vmobjlock);
680 		KASSERT(uvm_pagelookup(uvm.kernel_object, offset) == NULL);
681 		pg = uvm_pagealloc(uvm.kernel_object, offset, NULL, 0);
682 		if (pg) {
683 			pg->flags &= ~PG_BUSY;
684 			UVM_PAGE_OWN(pg, NULL);
685 		}
686 		simple_unlock(&uvm.kernel_object->vmobjlock);
687 		if (pg == NULL) {
688 			uvm_wait("km_alloc1w");
689 			continue;
690 		}
691 		pmap_enter(map->pmap, loopva, VM_PAGE_TO_PHYS(pg),
692 		    UVM_PROT_ALL, PMAP_WIRED | VM_PROT_READ | VM_PROT_WRITE);
693 		loopva += PAGE_SIZE;
694 		offset += PAGE_SIZE;
695 		size -= PAGE_SIZE;
696 	}
697 	pmap_update(map->pmap);
698 
699 	/*
700 	 * zero on request (note that "size" is now zero due to the above loop
701 	 * so we need to subtract kva from loopva to reconstruct the size).
702 	 */
703 
704 	if (zeroit)
705 		memset((caddr_t)kva, 0, loopva - kva);
706 	UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0);
707 	return(kva);
708 }
709 
710 /*
711  * uvm_km_valloc1: allocate zero-fill memory in the kernel's address space
712  *
713  * => memory is not allocated until fault time
714  * => the align, prefer and flags parameters are passed on to uvm_map().
715  *
716  * Note: this function is also the backend for these macros:
717  *	uvm_km_valloc
718  *	uvm_km_valloc_wait
719  *	uvm_km_valloc_prefer
720  *	uvm_km_valloc_prefer_wait
721  *	uvm_km_valloc_align
722  */
723 
724 vaddr_t
725 uvm_km_valloc1(map, size, align, prefer, flags)
726 	struct vm_map *map;
727 	vsize_t size;
728 	vsize_t align;
729 	voff_t prefer;
730 	uvm_flag_t flags;
731 {
732 	vaddr_t kva;
733 	int error;
734 	UVMHIST_FUNC("uvm_km_valloc1"); UVMHIST_CALLED(maphist);
735 
736 	UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x, align=0x%x, prefer=0x%x)",
737 		    map, size, align, prefer);
738 
739 	KASSERT(vm_map_pmap(map) == pmap_kernel());
740 
741 	size = round_page(size);
742 	/*
743 	 * Check if requested size is larger than the map, in which
744 	 * case we can't succeed.
745 	 */
746 	if (size > vm_map_max(map) - vm_map_min(map))
747 		return (0);
748 
749 	flags |= UVM_FLAG_QUANTUM;
750 	if ((flags & UVM_KMF_NOWAIT) == 0) /* XXX */
751 		flags |= UVM_FLAG_WAITVA;  /* XXX */
752 
753 	kva = vm_map_min(map);		/* hint */
754 
755 	/*
756 	 * allocate some virtual space.   will be demand filled
757 	 * by kernel_object.
758 	 */
759 
760 	error = uvm_map(map, &kva, size, uvm.kernel_object,
761 	    prefer, align, UVM_MAPFLAG(UVM_PROT_ALL,
762 	    UVM_PROT_ALL, UVM_INH_NONE, UVM_ADV_RANDOM, flags));
763 
764 	KASSERT(error == 0 || (flags & UVM_KMF_NOWAIT) != 0);
765 
766 	UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0);
767 
768 	return (kva);
769 }
770 
771 /* Function definitions for binary compatibility */
772 vaddr_t
773 uvm_km_kmemalloc(struct vm_map *map, struct uvm_object *obj,
774 		 vsize_t sz, int flags)
775 {
776 	return uvm_km_kmemalloc1(map, obj, sz, 0, UVM_UNKNOWN_OFFSET, flags);
777 }
778 
779 vaddr_t uvm_km_valloc(struct vm_map *map, vsize_t sz)
780 {
781 	return uvm_km_valloc1(map, sz, 0, UVM_UNKNOWN_OFFSET, UVM_KMF_NOWAIT);
782 }
783 
784 vaddr_t uvm_km_valloc_align(struct vm_map *map, vsize_t sz, vsize_t align)
785 {
786 	return uvm_km_valloc1(map, sz, align, UVM_UNKNOWN_OFFSET, UVM_KMF_NOWAIT);
787 }
788 
789 vaddr_t uvm_km_valloc_prefer_wait(struct vm_map *map, vsize_t sz, voff_t prefer)
790 {
791 	return uvm_km_valloc1(map, sz, 0, prefer, 0);
792 }
793 
794 vaddr_t uvm_km_valloc_wait(struct vm_map *map, vsize_t sz)
795 {
796 	return uvm_km_valloc1(map, sz, 0, UVM_UNKNOWN_OFFSET, 0);
797 }
798 
799 /* Sanity; must specify both or none. */
800 #if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \
801     (!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE))
802 #error Must specify MAP and UNMAP together.
803 #endif
804 
805 /*
806  * uvm_km_alloc_poolpage: allocate a page for the pool allocator
807  *
808  * => if the pmap specifies an alternate mapping method, we use it.
809  */
810 
811 /* ARGSUSED */
812 vaddr_t
813 uvm_km_alloc_poolpage_cache(map, obj, waitok)
814 	struct vm_map *map;
815 	struct uvm_object *obj;
816 	boolean_t waitok;
817 {
818 #if defined(PMAP_MAP_POOLPAGE)
819 	return uvm_km_alloc_poolpage1(map, obj, waitok);
820 #else
821 	struct vm_page *pg;
822 	struct pool *pp = &vm_map_to_kernel(map)->vmk_vacache;
823 	vaddr_t va;
824 	int s = 0xdeadbeaf; /* XXX: gcc */
825 	const boolean_t intrsafe = (map->flags & VM_MAP_INTRSAFE) != 0;
826 
827 	if ((map->flags & VM_MAP_VACACHE) == 0)
828 		return uvm_km_alloc_poolpage1(map, obj, waitok);
829 
830 	if (intrsafe)
831 		s = splvm();
832 	va = (vaddr_t)pool_get(pp, waitok ? PR_WAITOK : PR_NOWAIT);
833 	if (intrsafe)
834 		splx(s);
835 	if (va == 0)
836 		return 0;
837 	KASSERT(!pmap_extract(pmap_kernel(), va, NULL));
838 again:
839 	pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE);
840 	if (__predict_false(pg == NULL)) {
841 		if (waitok) {
842 			uvm_wait("plpg");
843 			goto again;
844 		} else {
845 			if (intrsafe)
846 				s = splvm();
847 			pool_put(pp, (void *)va);
848 			if (intrsafe)
849 				splx(s);
850 			return 0;
851 		}
852 	}
853 	pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg),
854 	    VM_PROT_READ|VM_PROT_WRITE);
855 	pmap_update(pmap_kernel());
856 
857 	return va;
858 #endif /* PMAP_MAP_POOLPAGE */
859 }
860 
861 vaddr_t
862 uvm_km_alloc_poolpage1(map, obj, waitok)
863 	struct vm_map *map;
864 	struct uvm_object *obj;
865 	boolean_t waitok;
866 {
867 #if defined(PMAP_MAP_POOLPAGE)
868 	struct vm_page *pg;
869 	vaddr_t va;
870 
871  again:
872 	pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE);
873 	if (__predict_false(pg == NULL)) {
874 		if (waitok) {
875 			uvm_wait("plpg");
876 			goto again;
877 		} else
878 			return (0);
879 	}
880 	va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg));
881 	if (__predict_false(va == 0))
882 		uvm_pagefree(pg);
883 	return (va);
884 #else
885 	vaddr_t va;
886 	int s = 0xdeadbeaf; /* XXX: gcc */
887 	const boolean_t intrsafe = (map->flags & VM_MAP_INTRSAFE) != 0;
888 
889 	if (intrsafe)
890 		s = splvm();
891 	va = uvm_km_kmemalloc(map, obj, PAGE_SIZE,
892 	    waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK);
893 	if (intrsafe)
894 		splx(s);
895 	return (va);
896 #endif /* PMAP_MAP_POOLPAGE */
897 }
898 
899 /*
900  * uvm_km_free_poolpage: free a previously allocated pool page
901  *
902  * => if the pmap specifies an alternate unmapping method, we use it.
903  */
904 
905 /* ARGSUSED */
906 void
907 uvm_km_free_poolpage_cache(map, addr)
908 	struct vm_map *map;
909 	vaddr_t addr;
910 {
911 #if defined(PMAP_UNMAP_POOLPAGE)
912 	uvm_km_free_poolpage1(map, addr);
913 #else
914 	struct pool *pp;
915 	int s = 0xdeadbeaf; /* XXX: gcc */
916 	const boolean_t intrsafe = (map->flags & VM_MAP_INTRSAFE) != 0;
917 
918 	if ((map->flags & VM_MAP_VACACHE) == 0) {
919 		uvm_km_free_poolpage1(map, addr);
920 		return;
921 	}
922 
923 	KASSERT(pmap_extract(pmap_kernel(), addr, NULL));
924 	uvm_km_pgremove_intrsafe(addr, addr + PAGE_SIZE);
925 	pmap_kremove(addr, PAGE_SIZE);
926 #if defined(DEBUG)
927 	pmap_update(pmap_kernel());
928 #endif
929 	KASSERT(!pmap_extract(pmap_kernel(), addr, NULL));
930 	pp = &vm_map_to_kernel(map)->vmk_vacache;
931 	if (intrsafe)
932 		s = splvm();
933 	pool_put(pp, (void *)addr);
934 	if (intrsafe)
935 		splx(s);
936 #endif
937 }
938 
939 /* ARGSUSED */
940 void
941 uvm_km_free_poolpage1(map, addr)
942 	struct vm_map *map;
943 	vaddr_t addr;
944 {
945 #if defined(PMAP_UNMAP_POOLPAGE)
946 	paddr_t pa;
947 
948 	pa = PMAP_UNMAP_POOLPAGE(addr);
949 	uvm_pagefree(PHYS_TO_VM_PAGE(pa));
950 #else
951 	int s = 0xdeadbeaf; /* XXX: gcc */
952 	const boolean_t intrsafe = (map->flags & VM_MAP_INTRSAFE) != 0;
953 
954 	if (intrsafe)
955 		s = splvm();
956 	uvm_km_free(map, addr, PAGE_SIZE);
957 	if (intrsafe)
958 		splx(s);
959 #endif /* PMAP_UNMAP_POOLPAGE */
960 }
961