xref: /netbsd-src/sys/rump/librump/rumpkern/vm.c (revision 7788a0781fe6ff2cce37368b4578a7ade0850cb1)
1 /*	$NetBSD: vm.c,v 1.144 2013/04/30 16:03:44 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2007-2011 Antti Kantee.  All Rights Reserved.
5  *
6  * Development of this software was supported by
7  * The Finnish Cultural Foundation and the Research Foundation of
8  * The Helsinki University of Technology.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
20  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Virtual memory emulation routines.
34  */
35 
36 /*
37  * XXX: we abuse pg->uanon for the virtual address of the storage
38  * for each page.  phys_addr would fit the job description better,
39  * except that it will create unnecessary lossage on some platforms
40  * due to not being a pointer type.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: vm.c,v 1.144 2013/04/30 16:03:44 pooka Exp $");
45 
46 #include <sys/param.h>
47 #include <sys/atomic.h>
48 #include <sys/buf.h>
49 #include <sys/kernel.h>
50 #include <sys/kmem.h>
51 #include <sys/vmem.h>
52 #include <sys/mman.h>
53 #include <sys/null.h>
54 #include <sys/vnode.h>
55 
56 #include <machine/pmap.h>
57 
58 #include <rump/rumpuser.h>
59 
60 #include <uvm/uvm.h>
61 #include <uvm/uvm_ddb.h>
62 #include <uvm/uvm_pdpolicy.h>
63 #include <uvm/uvm_prot.h>
64 #include <uvm/uvm_readahead.h>
65 
66 #include "rump_private.h"
67 #include "rump_vfs_private.h"
68 
69 kmutex_t uvm_pageqlock;
70 kmutex_t uvm_swap_data_lock;
71 
72 struct uvmexp uvmexp;
73 struct uvm uvm;
74 
75 #ifdef __uvmexp_pagesize
76 const int * const uvmexp_pagesize = &uvmexp.pagesize;
77 const int * const uvmexp_pagemask = &uvmexp.pagemask;
78 const int * const uvmexp_pageshift = &uvmexp.pageshift;
79 #endif
80 
81 struct vm_map rump_vmmap;
82 
83 static struct vm_map kernel_map_store;
84 struct vm_map *kernel_map = &kernel_map_store;
85 
86 static struct vm_map module_map_store;
87 extern struct vm_map *module_map;
88 
89 vmem_t *kmem_arena;
90 vmem_t *kmem_va_arena;
91 
92 static unsigned int pdaemon_waiters;
93 static kmutex_t pdaemonmtx;
94 static kcondvar_t pdaemoncv, oomwait;
95 
96 unsigned long rump_physmemlimit = RUMPMEM_UNLIMITED;
97 static unsigned long curphysmem;
98 static unsigned long dddlim;		/* 90% of memory limit used */
99 #define NEED_PAGEDAEMON() \
100     (rump_physmemlimit != RUMPMEM_UNLIMITED && curphysmem > dddlim)
101 
102 /*
103  * Try to free two pages worth of pages from objects.
104  * If this succesfully frees a full page cache page, we'll
105  * free the released page plus PAGE_SIZE/sizeof(vm_page).
106  */
107 #define PAGEDAEMON_OBJCHUNK (2*PAGE_SIZE / sizeof(struct vm_page))
108 
109 /*
110  * Keep a list of least recently used pages.  Since the only way a
111  * rump kernel can "access" a page is via lookup, we put the page
112  * at the back of queue every time a lookup for it is done.  If the
113  * page is in front of this global queue and we're short of memory,
114  * it's a candidate for pageout.
115  */
116 static struct pglist vmpage_lruqueue;
117 static unsigned vmpage_onqueue;
118 
119 static int
120 pg_compare_key(void *ctx, const void *n, const void *key)
121 {
122 	voff_t a = ((const struct vm_page *)n)->offset;
123 	voff_t b = *(const voff_t *)key;
124 
125 	if (a < b)
126 		return -1;
127 	else if (a > b)
128 		return 1;
129 	else
130 		return 0;
131 }
132 
133 static int
134 pg_compare_nodes(void *ctx, const void *n1, const void *n2)
135 {
136 
137 	return pg_compare_key(ctx, n1, &((const struct vm_page *)n2)->offset);
138 }
139 
140 const rb_tree_ops_t uvm_page_tree_ops = {
141 	.rbto_compare_nodes = pg_compare_nodes,
142 	.rbto_compare_key = pg_compare_key,
143 	.rbto_node_offset = offsetof(struct vm_page, rb_node),
144 	.rbto_context = NULL
145 };
146 
147 /*
148  * vm pages
149  */
150 
151 static int
152 pgctor(void *arg, void *obj, int flags)
153 {
154 	struct vm_page *pg = obj;
155 
156 	memset(pg, 0, sizeof(*pg));
157 	pg->uanon = rump_hypermalloc(PAGE_SIZE, PAGE_SIZE,
158 	    (flags & PR_WAITOK) == PR_WAITOK, "pgalloc");
159 	return pg->uanon == NULL;
160 }
161 
162 static void
163 pgdtor(void *arg, void *obj)
164 {
165 	struct vm_page *pg = obj;
166 
167 	rump_hyperfree(pg->uanon, PAGE_SIZE);
168 }
169 
170 static struct pool_cache pagecache;
171 
172 /*
173  * Called with the object locked.  We don't support anons.
174  */
175 struct vm_page *
176 uvm_pagealloc_strat(struct uvm_object *uobj, voff_t off, struct vm_anon *anon,
177 	int flags, int strat, int free_list)
178 {
179 	struct vm_page *pg;
180 
181 	KASSERT(uobj && mutex_owned(uobj->vmobjlock));
182 	KASSERT(anon == NULL);
183 
184 	pg = pool_cache_get(&pagecache, PR_NOWAIT);
185 	if (__predict_false(pg == NULL)) {
186 		return NULL;
187 	}
188 
189 	pg->offset = off;
190 	pg->uobject = uobj;
191 
192 	pg->flags = PG_CLEAN|PG_BUSY|PG_FAKE;
193 	if (flags & UVM_PGA_ZERO) {
194 		uvm_pagezero(pg);
195 	}
196 
197 	TAILQ_INSERT_TAIL(&uobj->memq, pg, listq.queue);
198 	(void)rb_tree_insert_node(&uobj->rb_tree, pg);
199 
200 	/*
201 	 * Don't put anons on the LRU page queue.  We can't flush them
202 	 * (there's no concept of swap in a rump kernel), so no reason
203 	 * to bother with them.
204 	 */
205 	if (!UVM_OBJ_IS_AOBJ(uobj)) {
206 		atomic_inc_uint(&vmpage_onqueue);
207 		mutex_enter(&uvm_pageqlock);
208 		TAILQ_INSERT_TAIL(&vmpage_lruqueue, pg, pageq.queue);
209 		mutex_exit(&uvm_pageqlock);
210 	}
211 
212 	uobj->uo_npages++;
213 
214 	return pg;
215 }
216 
217 /*
218  * Release a page.
219  *
220  * Called with the vm object locked.
221  */
222 void
223 uvm_pagefree(struct vm_page *pg)
224 {
225 	struct uvm_object *uobj = pg->uobject;
226 
227 	KASSERT(mutex_owned(&uvm_pageqlock));
228 	KASSERT(mutex_owned(uobj->vmobjlock));
229 
230 	if (pg->flags & PG_WANTED)
231 		wakeup(pg);
232 
233 	TAILQ_REMOVE(&uobj->memq, pg, listq.queue);
234 
235 	uobj->uo_npages--;
236 	rb_tree_remove_node(&uobj->rb_tree, pg);
237 
238 	if (!UVM_OBJ_IS_AOBJ(uobj)) {
239 		TAILQ_REMOVE(&vmpage_lruqueue, pg, pageq.queue);
240 		atomic_dec_uint(&vmpage_onqueue);
241 	}
242 
243 	pool_cache_put(&pagecache, pg);
244 }
245 
246 void
247 uvm_pagezero(struct vm_page *pg)
248 {
249 
250 	pg->flags &= ~PG_CLEAN;
251 	memset((void *)pg->uanon, 0, PAGE_SIZE);
252 }
253 
254 /*
255  * uvm_page_locked_p: return true if object associated with page is
256  * locked.  this is a weak check for runtime assertions only.
257  */
258 
259 bool
260 uvm_page_locked_p(struct vm_page *pg)
261 {
262 
263 	return mutex_owned(pg->uobject->vmobjlock);
264 }
265 
266 /*
267  * Misc routines
268  */
269 
270 static kmutex_t pagermtx;
271 
272 void
273 uvm_init(void)
274 {
275 	char buf[64];
276 
277 	if (rumpuser_getparam("RUMP_MEMLIMIT", buf, sizeof(buf)) == 0) {
278 		unsigned long tmp;
279 		char *ep;
280 		int mult;
281 
282 		tmp = strtoul(buf, &ep, 10);
283 		if (strlen(ep) > 1)
284 			panic("uvm_init: invalid RUMP_MEMLIMIT: %s", buf);
285 
286 		/* mini-dehumanize-number */
287 		mult = 1;
288 		switch (*ep) {
289 		case 'k':
290 			mult = 1024;
291 			break;
292 		case 'm':
293 			mult = 1024*1024;
294 			break;
295 		case 'g':
296 			mult = 1024*1024*1024;
297 			break;
298 		case 0:
299 			break;
300 		default:
301 			panic("uvm_init: invalid RUMP_MEMLIMIT: %s", buf);
302 		}
303 		rump_physmemlimit = tmp * mult;
304 
305 		if (rump_physmemlimit / mult != tmp)
306 			panic("uvm_init: RUMP_MEMLIMIT overflow: %s", buf);
307 		/* it's not like we'd get far with, say, 1 byte, but ... */
308 		if (rump_physmemlimit == 0)
309 			panic("uvm_init: no memory");
310 
311 #define HUMANIZE_BYTES 9
312 		CTASSERT(sizeof(buf) >= HUMANIZE_BYTES);
313 		format_bytes(buf, HUMANIZE_BYTES, rump_physmemlimit);
314 #undef HUMANIZE_BYTES
315 		dddlim = 9 * (rump_physmemlimit / 10);
316 	} else {
317 		strlcpy(buf, "unlimited (host limit)", sizeof(buf));
318 	}
319 	aprint_verbose("total memory = %s\n", buf);
320 
321 	TAILQ_INIT(&vmpage_lruqueue);
322 
323 	uvmexp.free = 1024*1024; /* XXX: arbitrary & not updated */
324 
325 #ifndef __uvmexp_pagesize
326 	uvmexp.pagesize = PAGE_SIZE;
327 	uvmexp.pagemask = PAGE_MASK;
328 	uvmexp.pageshift = PAGE_SHIFT;
329 #else
330 #define FAKE_PAGE_SHIFT 12
331 	uvmexp.pageshift = FAKE_PAGE_SHIFT;
332 	uvmexp.pagesize = 1<<FAKE_PAGE_SHIFT;
333 	uvmexp.pagemask = (1<<FAKE_PAGE_SHIFT)-1;
334 #undef FAKE_PAGE_SHIFT
335 #endif
336 
337 	mutex_init(&pagermtx, MUTEX_DEFAULT, IPL_NONE);
338 	mutex_init(&uvm_pageqlock, MUTEX_DEFAULT, IPL_NONE);
339 	mutex_init(&uvm_swap_data_lock, MUTEX_DEFAULT, IPL_NONE);
340 
341 	mutex_init(&pdaemonmtx, MUTEX_DEFAULT, IPL_NONE);
342 	cv_init(&pdaemoncv, "pdaemon");
343 	cv_init(&oomwait, "oomwait");
344 
345 	module_map = &module_map_store;
346 
347 	kernel_map->pmap = pmap_kernel();
348 
349 	pool_subsystem_init();
350 
351 	kmem_arena = vmem_create("kmem", 0, 1024*1024, PAGE_SIZE,
352 	    NULL, NULL, NULL,
353 	    0, VM_NOSLEEP | VM_BOOTSTRAP, IPL_VM);
354 
355 	vmem_subsystem_init(kmem_arena);
356 
357 	kmem_va_arena = vmem_create("kva", 0, 0, PAGE_SIZE,
358 	    vmem_alloc, vmem_free, kmem_arena,
359 	    8 * PAGE_SIZE, VM_NOSLEEP | VM_BOOTSTRAP, IPL_VM);
360 
361 	pool_cache_bootstrap(&pagecache, sizeof(struct vm_page), 0, 0, 0,
362 	    "page$", NULL, IPL_NONE, pgctor, pgdtor, NULL);
363 }
364 
365 void
366 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, vaddr_t vmax)
367 {
368 
369 	vm->vm_map.pmap = pmap_kernel();
370 	vm->vm_refcnt = 1;
371 }
372 
373 void
374 uvm_pagewire(struct vm_page *pg)
375 {
376 
377 	/* nada */
378 }
379 
380 void
381 uvm_pageunwire(struct vm_page *pg)
382 {
383 
384 	/* nada */
385 }
386 
387 /* where's your schmonz now? */
388 #define PUNLIMIT(a)	\
389 p->p_rlimit[a].rlim_cur = p->p_rlimit[a].rlim_max = RLIM_INFINITY;
390 void
391 uvm_init_limits(struct proc *p)
392 {
393 
394 	PUNLIMIT(RLIMIT_STACK);
395 	PUNLIMIT(RLIMIT_DATA);
396 	PUNLIMIT(RLIMIT_RSS);
397 	PUNLIMIT(RLIMIT_AS);
398 	/* nice, cascade */
399 }
400 #undef PUNLIMIT
401 
402 /*
403  * This satisfies the "disgusting mmap hack" used by proplib.
404  * We probably should grow some more assertables to make sure we're
405  * not satisfying anything we shouldn't be satisfying.
406  */
407 int
408 uvm_mmap(struct vm_map *map, vaddr_t *addr, vsize_t size, vm_prot_t prot,
409 	vm_prot_t maxprot, int flags, void *handle, voff_t off, vsize_t locklim)
410 {
411 	void *uaddr;
412 	int error;
413 
414 	if (prot != (VM_PROT_READ | VM_PROT_WRITE))
415 		panic("uvm_mmap() variant unsupported");
416 	if (flags != (MAP_PRIVATE | MAP_ANON))
417 		panic("uvm_mmap() variant unsupported");
418 
419 	/* no reason in particular, but cf. uvm_default_mapaddr() */
420 	if (*addr != 0)
421 		panic("uvm_mmap() variant unsupported");
422 
423 	if (RUMP_LOCALPROC_P(curproc)) {
424 		error = rumpuser_anonmmap(NULL, size, 0, 0, &uaddr);
425 	} else {
426 		error = rumpuser_sp_anonmmap(curproc->p_vmspace->vm_map.pmap,
427 		    size, &uaddr);
428 	}
429 	if (error)
430 		return error;
431 
432 	*addr = (vaddr_t)uaddr;
433 	return 0;
434 }
435 
436 struct pagerinfo {
437 	vaddr_t pgr_kva;
438 	int pgr_npages;
439 	struct vm_page **pgr_pgs;
440 	bool pgr_read;
441 
442 	LIST_ENTRY(pagerinfo) pgr_entries;
443 };
444 static LIST_HEAD(, pagerinfo) pagerlist = LIST_HEAD_INITIALIZER(pagerlist);
445 
446 /*
447  * Pager "map" in routine.  Instead of mapping, we allocate memory
448  * and copy page contents there.  Not optimal or even strictly
449  * correct (the caller might modify the page contents after mapping
450  * them in), but what the heck.  Assumes UVMPAGER_MAPIN_WAITOK.
451  */
452 vaddr_t
453 uvm_pagermapin(struct vm_page **pgs, int npages, int flags)
454 {
455 	struct pagerinfo *pgri;
456 	vaddr_t curkva;
457 	int i;
458 
459 	/* allocate structures */
460 	pgri = kmem_alloc(sizeof(*pgri), KM_SLEEP);
461 	pgri->pgr_kva = (vaddr_t)kmem_alloc(npages * PAGE_SIZE, KM_SLEEP);
462 	pgri->pgr_npages = npages;
463 	pgri->pgr_pgs = kmem_alloc(sizeof(struct vm_page *) * npages, KM_SLEEP);
464 	pgri->pgr_read = (flags & UVMPAGER_MAPIN_READ) != 0;
465 
466 	/* copy contents to "mapped" memory */
467 	for (i = 0, curkva = pgri->pgr_kva;
468 	    i < npages;
469 	    i++, curkva += PAGE_SIZE) {
470 		/*
471 		 * We need to copy the previous contents of the pages to
472 		 * the window even if we are reading from the
473 		 * device, since the device might not fill the contents of
474 		 * the full mapped range and we will end up corrupting
475 		 * data when we unmap the window.
476 		 */
477 		memcpy((void*)curkva, pgs[i]->uanon, PAGE_SIZE);
478 		pgri->pgr_pgs[i] = pgs[i];
479 	}
480 
481 	mutex_enter(&pagermtx);
482 	LIST_INSERT_HEAD(&pagerlist, pgri, pgr_entries);
483 	mutex_exit(&pagermtx);
484 
485 	return pgri->pgr_kva;
486 }
487 
488 /*
489  * map out the pager window.  return contents from VA to page storage
490  * and free structures.
491  *
492  * Note: does not currently support partial frees
493  */
494 void
495 uvm_pagermapout(vaddr_t kva, int npages)
496 {
497 	struct pagerinfo *pgri;
498 	vaddr_t curkva;
499 	int i;
500 
501 	mutex_enter(&pagermtx);
502 	LIST_FOREACH(pgri, &pagerlist, pgr_entries) {
503 		if (pgri->pgr_kva == kva)
504 			break;
505 	}
506 	KASSERT(pgri);
507 	if (pgri->pgr_npages != npages)
508 		panic("uvm_pagermapout: partial unmapping not supported");
509 	LIST_REMOVE(pgri, pgr_entries);
510 	mutex_exit(&pagermtx);
511 
512 	if (pgri->pgr_read) {
513 		for (i = 0, curkva = pgri->pgr_kva;
514 		    i < pgri->pgr_npages;
515 		    i++, curkva += PAGE_SIZE) {
516 			memcpy(pgri->pgr_pgs[i]->uanon,(void*)curkva,PAGE_SIZE);
517 		}
518 	}
519 
520 	kmem_free(pgri->pgr_pgs, npages * sizeof(struct vm_page *));
521 	kmem_free((void*)pgri->pgr_kva, npages * PAGE_SIZE);
522 	kmem_free(pgri, sizeof(*pgri));
523 }
524 
525 /*
526  * convert va in pager window to page structure.
527  * XXX: how expensive is this (global lock, list traversal)?
528  */
529 struct vm_page *
530 uvm_pageratop(vaddr_t va)
531 {
532 	struct pagerinfo *pgri;
533 	struct vm_page *pg = NULL;
534 	int i;
535 
536 	mutex_enter(&pagermtx);
537 	LIST_FOREACH(pgri, &pagerlist, pgr_entries) {
538 		if (pgri->pgr_kva <= va
539 		    && va < pgri->pgr_kva + pgri->pgr_npages*PAGE_SIZE)
540 			break;
541 	}
542 	if (pgri) {
543 		i = (va - pgri->pgr_kva) >> PAGE_SHIFT;
544 		pg = pgri->pgr_pgs[i];
545 	}
546 	mutex_exit(&pagermtx);
547 
548 	return pg;
549 }
550 
551 /*
552  * Called with the vm object locked.
553  *
554  * Put vnode object pages at the end of the access queue to indicate
555  * they have been recently accessed and should not be immediate
556  * candidates for pageout.  Do not do this for lookups done by
557  * the pagedaemon to mimic pmap_kentered mappings which don't track
558  * access information.
559  */
560 struct vm_page *
561 uvm_pagelookup(struct uvm_object *uobj, voff_t off)
562 {
563 	struct vm_page *pg;
564 	bool ispagedaemon = curlwp == uvm.pagedaemon_lwp;
565 
566 	pg = rb_tree_find_node(&uobj->rb_tree, &off);
567 	if (pg && !UVM_OBJ_IS_AOBJ(pg->uobject) && !ispagedaemon) {
568 		mutex_enter(&uvm_pageqlock);
569 		TAILQ_REMOVE(&vmpage_lruqueue, pg, pageq.queue);
570 		TAILQ_INSERT_TAIL(&vmpage_lruqueue, pg, pageq.queue);
571 		mutex_exit(&uvm_pageqlock);
572 	}
573 
574 	return pg;
575 }
576 
577 void
578 uvm_page_unbusy(struct vm_page **pgs, int npgs)
579 {
580 	struct vm_page *pg;
581 	int i;
582 
583 	KASSERT(npgs > 0);
584 	KASSERT(mutex_owned(pgs[0]->uobject->vmobjlock));
585 
586 	for (i = 0; i < npgs; i++) {
587 		pg = pgs[i];
588 		if (pg == NULL)
589 			continue;
590 
591 		KASSERT(pg->flags & PG_BUSY);
592 		if (pg->flags & PG_WANTED)
593 			wakeup(pg);
594 		if (pg->flags & PG_RELEASED)
595 			uvm_pagefree(pg);
596 		else
597 			pg->flags &= ~(PG_WANTED|PG_BUSY);
598 	}
599 }
600 
601 void
602 uvm_estimatepageable(int *active, int *inactive)
603 {
604 
605 	/* XXX: guessing game */
606 	*active = 1024;
607 	*inactive = 1024;
608 }
609 
610 bool
611 vm_map_starved_p(struct vm_map *map)
612 {
613 
614 	if (map->flags & VM_MAP_WANTVA)
615 		return true;
616 
617 	return false;
618 }
619 
620 int
621 uvm_loan(struct vm_map *map, vaddr_t start, vsize_t len, void *v, int flags)
622 {
623 
624 	panic("%s: unimplemented", __func__);
625 }
626 
627 void
628 uvm_unloan(void *v, int npages, int flags)
629 {
630 
631 	panic("%s: unimplemented", __func__);
632 }
633 
634 int
635 uvm_loanuobjpages(struct uvm_object *uobj, voff_t pgoff, int orignpages,
636 	struct vm_page **opp)
637 {
638 
639 	return EBUSY;
640 }
641 
642 struct vm_page *
643 uvm_loanbreak(struct vm_page *pg)
644 {
645 
646 	panic("%s: unimplemented", __func__);
647 }
648 
649 void
650 ubc_purge(struct uvm_object *uobj)
651 {
652 
653 }
654 
655 #ifdef DEBUGPRINT
656 void
657 uvm_object_printit(struct uvm_object *uobj, bool full,
658 	void (*pr)(const char *, ...))
659 {
660 
661 	pr("VM OBJECT at %p, refs %d", uobj, uobj->uo_refs);
662 }
663 #endif
664 
665 vaddr_t
666 uvm_default_mapaddr(struct proc *p, vaddr_t base, vsize_t sz)
667 {
668 
669 	return 0;
670 }
671 
672 int
673 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end,
674 	vm_prot_t prot, bool set_max)
675 {
676 
677 	return EOPNOTSUPP;
678 }
679 
680 /*
681  * UVM km
682  */
683 
684 vaddr_t
685 uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags)
686 {
687 	void *rv, *desired = NULL;
688 	int alignbit, error;
689 
690 #ifdef __x86_64__
691 	/*
692 	 * On amd64, allocate all module memory from the lowest 2GB.
693 	 * This is because NetBSD kernel modules are compiled
694 	 * with -mcmodel=kernel and reserve only 4 bytes for
695 	 * offsets.  If we load code compiled with -mcmodel=kernel
696 	 * anywhere except the lowest or highest 2GB, it will not
697 	 * work.  Since userspace does not have access to the highest
698 	 * 2GB, use the lowest 2GB.
699 	 *
700 	 * Note: this assumes the rump kernel resides in
701 	 * the lowest 2GB as well.
702 	 *
703 	 * Note2: yes, it's a quick hack, but since this the only
704 	 * place where we care about the map we're allocating from,
705 	 * just use a simple "if" instead of coming up with a fancy
706 	 * generic solution.
707 	 */
708 	if (map == module_map) {
709 		desired = (void *)(0x80000000 - size);
710 	}
711 #endif
712 
713 	if (__predict_false(map == module_map)) {
714 		alignbit = 0;
715 		if (align) {
716 			alignbit = ffs(align)-1;
717 		}
718 		error = rumpuser_anonmmap(desired, size, alignbit,
719 		    flags & UVM_KMF_EXEC, &rv);
720 	} else {
721 		error = rumpuser_malloc(size, align, &rv);
722 	}
723 
724 	if (error) {
725 		if (flags & (UVM_KMF_CANFAIL | UVM_KMF_NOWAIT))
726 			return 0;
727 		else
728 			panic("uvm_km_alloc failed");
729 	}
730 
731 	if (flags & UVM_KMF_ZERO)
732 		memset(rv, 0, size);
733 
734 	return (vaddr_t)rv;
735 }
736 
737 void
738 uvm_km_free(struct vm_map *map, vaddr_t vaddr, vsize_t size, uvm_flag_t flags)
739 {
740 
741 	if (__predict_false(map == module_map))
742 		rumpuser_unmap((void *)vaddr, size);
743 	else
744 		rumpuser_free((void *)vaddr, size);
745 }
746 
747 struct vm_map *
748 uvm_km_suballoc(struct vm_map *map, vaddr_t *minaddr, vaddr_t *maxaddr,
749 	vsize_t size, int pageable, bool fixed, struct vm_map *submap)
750 {
751 
752 	return (struct vm_map *)417416;
753 }
754 
755 int
756 uvm_km_kmem_alloc(vmem_t *vm, vmem_size_t size, vm_flag_t flags,
757     vmem_addr_t *addr)
758 {
759 	vaddr_t va;
760 	va = (vaddr_t)rump_hypermalloc(size, PAGE_SIZE,
761 	    (flags & VM_SLEEP), "kmalloc");
762 
763 	if (va) {
764 		*addr = va;
765 		return 0;
766 	} else {
767 		return ENOMEM;
768 	}
769 }
770 
771 void
772 uvm_km_kmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
773 {
774 
775 	rump_hyperfree((void *)addr, size);
776 }
777 
778 /*
779  * VM space locking routines.  We don't really have to do anything,
780  * since the pages are always "wired" (both local and remote processes).
781  */
782 int
783 uvm_vslock(struct vmspace *vs, void *addr, size_t len, vm_prot_t access)
784 {
785 
786 	return 0;
787 }
788 
789 void
790 uvm_vsunlock(struct vmspace *vs, void *addr, size_t len)
791 {
792 
793 }
794 
795 /*
796  * For the local case the buffer mappers don't need to do anything.
797  * For the remote case we need to reserve space and copy data in or
798  * out, depending on B_READ/B_WRITE.
799  */
800 int
801 vmapbuf(struct buf *bp, vsize_t len)
802 {
803 	int error = 0;
804 
805 	bp->b_saveaddr = bp->b_data;
806 
807 	/* remote case */
808 	if (!RUMP_LOCALPROC_P(curproc)) {
809 		bp->b_data = rump_hypermalloc(len, 0, true, "vmapbuf");
810 		if (BUF_ISWRITE(bp)) {
811 			error = copyin(bp->b_saveaddr, bp->b_data, len);
812 			if (error) {
813 				rump_hyperfree(bp->b_data, len);
814 				bp->b_data = bp->b_saveaddr;
815 				bp->b_saveaddr = 0;
816 			}
817 		}
818 	}
819 
820 	return error;
821 }
822 
823 void
824 vunmapbuf(struct buf *bp, vsize_t len)
825 {
826 
827 	/* remote case */
828 	if (!RUMP_LOCALPROC_P(bp->b_proc)) {
829 		if (BUF_ISREAD(bp)) {
830 			bp->b_error = copyout_proc(bp->b_proc,
831 			    bp->b_data, bp->b_saveaddr, len);
832 		}
833 		rump_hyperfree(bp->b_data, len);
834 	}
835 
836 	bp->b_data = bp->b_saveaddr;
837 	bp->b_saveaddr = 0;
838 }
839 
840 void
841 uvmspace_addref(struct vmspace *vm)
842 {
843 
844 	/*
845 	 * No dynamically allocated vmspaces exist.
846 	 */
847 }
848 
849 void
850 uvmspace_free(struct vmspace *vm)
851 {
852 
853 	/* nothing for now */
854 }
855 
856 /*
857  * page life cycle stuff.  it really doesn't exist, so just stubs.
858  */
859 
860 void
861 uvm_pageactivate(struct vm_page *pg)
862 {
863 
864 	/* nada */
865 }
866 
867 void
868 uvm_pagedeactivate(struct vm_page *pg)
869 {
870 
871 	/* nada */
872 }
873 
874 void
875 uvm_pagedequeue(struct vm_page *pg)
876 {
877 
878 	/* nada*/
879 }
880 
881 void
882 uvm_pageenqueue(struct vm_page *pg)
883 {
884 
885 	/* nada */
886 }
887 
888 void
889 uvmpdpol_anfree(struct vm_anon *an)
890 {
891 
892 	/* nada */
893 }
894 
895 /*
896  * Physical address accessors.
897  */
898 
899 struct vm_page *
900 uvm_phys_to_vm_page(paddr_t pa)
901 {
902 
903 	return NULL;
904 }
905 
906 paddr_t
907 uvm_vm_page_to_phys(const struct vm_page *pg)
908 {
909 
910 	return 0;
911 }
912 
913 /*
914  * Routines related to the Page Baroness.
915  */
916 
917 void
918 uvm_wait(const char *msg)
919 {
920 
921 	if (__predict_false(curlwp == uvm.pagedaemon_lwp))
922 		panic("pagedaemon out of memory");
923 	if (__predict_false(rump_threads == 0))
924 		panic("pagedaemon missing (RUMP_THREADS = 0)");
925 
926 	mutex_enter(&pdaemonmtx);
927 	pdaemon_waiters++;
928 	cv_signal(&pdaemoncv);
929 	cv_wait(&oomwait, &pdaemonmtx);
930 	mutex_exit(&pdaemonmtx);
931 }
932 
933 void
934 uvm_pageout_start(int npages)
935 {
936 
937 	mutex_enter(&pdaemonmtx);
938 	uvmexp.paging += npages;
939 	mutex_exit(&pdaemonmtx);
940 }
941 
942 void
943 uvm_pageout_done(int npages)
944 {
945 
946 	if (!npages)
947 		return;
948 
949 	mutex_enter(&pdaemonmtx);
950 	KASSERT(uvmexp.paging >= npages);
951 	uvmexp.paging -= npages;
952 
953 	if (pdaemon_waiters) {
954 		pdaemon_waiters = 0;
955 		cv_broadcast(&oomwait);
956 	}
957 	mutex_exit(&pdaemonmtx);
958 }
959 
960 static bool
961 processpage(struct vm_page *pg, bool *lockrunning)
962 {
963 	struct uvm_object *uobj;
964 
965 	uobj = pg->uobject;
966 	if (mutex_tryenter(uobj->vmobjlock)) {
967 		if ((pg->flags & PG_BUSY) == 0) {
968 			mutex_exit(&uvm_pageqlock);
969 			uobj->pgops->pgo_put(uobj, pg->offset,
970 			    pg->offset + PAGE_SIZE,
971 			    PGO_CLEANIT|PGO_FREE);
972 			KASSERT(!mutex_owned(uobj->vmobjlock));
973 			return true;
974 		} else {
975 			mutex_exit(uobj->vmobjlock);
976 		}
977 	} else if (*lockrunning == false && ncpu > 1) {
978 		CPU_INFO_ITERATOR cii;
979 		struct cpu_info *ci;
980 		struct lwp *l;
981 
982 		l = mutex_owner(uobj->vmobjlock);
983 		for (CPU_INFO_FOREACH(cii, ci)) {
984 			if (ci->ci_curlwp == l) {
985 				*lockrunning = true;
986 				break;
987 			}
988 		}
989 	}
990 
991 	return false;
992 }
993 
994 /*
995  * The Diabolical pageDaemon Director (DDD).
996  *
997  * This routine can always use better heuristics.
998  */
999 void
1000 uvm_pageout(void *arg)
1001 {
1002 	struct vm_page *pg;
1003 	struct pool *pp, *pp_first;
1004 	int cleaned, skip, skipped;
1005 	bool succ;
1006 	bool lockrunning;
1007 
1008 	mutex_enter(&pdaemonmtx);
1009 	for (;;) {
1010 		if (!NEED_PAGEDAEMON()) {
1011 			kernel_map->flags &= ~VM_MAP_WANTVA;
1012 		}
1013 
1014 		if (pdaemon_waiters) {
1015 			pdaemon_waiters = 0;
1016 			cv_broadcast(&oomwait);
1017 		}
1018 
1019 		cv_wait(&pdaemoncv, &pdaemonmtx);
1020 		uvmexp.pdwoke++;
1021 
1022 		/* tell the world that we are hungry */
1023 		kernel_map->flags |= VM_MAP_WANTVA;
1024 		mutex_exit(&pdaemonmtx);
1025 
1026 		/*
1027 		 * step one: reclaim the page cache.  this should give
1028 		 * us the biggest earnings since whole pages are released
1029 		 * into backing memory.
1030 		 */
1031 		pool_cache_reclaim(&pagecache);
1032 		if (!NEED_PAGEDAEMON()) {
1033 			mutex_enter(&pdaemonmtx);
1034 			continue;
1035 		}
1036 
1037 		/*
1038 		 * Ok, so that didn't help.  Next, try to hunt memory
1039 		 * by pushing out vnode pages.  The pages might contain
1040 		 * useful cached data, but we need the memory.
1041 		 */
1042 		cleaned = 0;
1043 		skip = 0;
1044 		lockrunning = false;
1045  again:
1046 		mutex_enter(&uvm_pageqlock);
1047 		while (cleaned < PAGEDAEMON_OBJCHUNK) {
1048 			skipped = 0;
1049 			TAILQ_FOREACH(pg, &vmpage_lruqueue, pageq.queue) {
1050 
1051 				/*
1052 				 * skip over pages we _might_ have tried
1053 				 * to handle earlier.  they might not be
1054 				 * exactly the same ones, but I'm not too
1055 				 * concerned.
1056 				 */
1057 				while (skipped++ < skip)
1058 					continue;
1059 
1060 				if (processpage(pg, &lockrunning)) {
1061 					cleaned++;
1062 					goto again;
1063 				}
1064 
1065 				skip++;
1066 			}
1067 			break;
1068 		}
1069 		mutex_exit(&uvm_pageqlock);
1070 
1071 		/*
1072 		 * Ok, someone is running with an object lock held.
1073 		 * We want to yield the host CPU to make sure the
1074 		 * thread is not parked on the host.  Since sched_yield()
1075 		 * doesn't appear to do anything on NetBSD, nanosleep
1076 		 * for the smallest possible time and hope we're back in
1077 		 * the game soon.
1078 		 */
1079 		if (cleaned == 0 && lockrunning) {
1080 			rumpuser_clock_sleep(RUMPUSER_CLOCK_RELWALL, 0, 1);
1081 
1082 			lockrunning = false;
1083 			skip = 0;
1084 
1085 			/* and here we go again */
1086 			goto again;
1087 		}
1088 
1089 		/*
1090 		 * And of course we need to reclaim the page cache
1091 		 * again to actually release memory.
1092 		 */
1093 		pool_cache_reclaim(&pagecache);
1094 		if (!NEED_PAGEDAEMON()) {
1095 			mutex_enter(&pdaemonmtx);
1096 			continue;
1097 		}
1098 
1099 		/*
1100 		 * And then drain the pools.  Wipe them out ... all of them.
1101 		 */
1102 		for (pp_first = NULL;;) {
1103 			if (rump_vfs_drainbufs)
1104 				rump_vfs_drainbufs(10 /* XXX: estimate! */);
1105 
1106 			succ = pool_drain(&pp);
1107 			if (succ || pp == pp_first)
1108 				break;
1109 
1110 			if (pp_first == NULL)
1111 				pp_first = pp;
1112 		}
1113 
1114 		/*
1115 		 * Need to use PYEC on our bag of tricks.
1116 		 * Unfortunately, the wife just borrowed it.
1117 		 */
1118 
1119 		mutex_enter(&pdaemonmtx);
1120 		if (!succ && cleaned == 0 && pdaemon_waiters &&
1121 		    uvmexp.paging == 0) {
1122 			rumpuser_dprintf("pagedaemoness: failed to reclaim "
1123 			    "memory ... sleeping (deadlock?)\n");
1124 			cv_timedwait(&pdaemoncv, &pdaemonmtx, hz);
1125 		}
1126 	}
1127 
1128 	panic("you can swap out any time you like, but you can never leave");
1129 }
1130 
1131 void
1132 uvm_kick_pdaemon()
1133 {
1134 
1135 	/*
1136 	 * Wake up the diabolical pagedaemon director if we are over
1137 	 * 90% of the memory limit.  This is a complete and utter
1138 	 * stetson-harrison decision which you are allowed to finetune.
1139 	 * Don't bother locking.  If we have some unflushed caches,
1140 	 * other waker-uppers will deal with the issue.
1141 	 */
1142 	if (NEED_PAGEDAEMON()) {
1143 		cv_signal(&pdaemoncv);
1144 	}
1145 }
1146 
1147 void *
1148 rump_hypermalloc(size_t howmuch, int alignment, bool waitok, const char *wmsg)
1149 {
1150 	unsigned long newmem;
1151 	void *rv;
1152 	int error;
1153 
1154 	uvm_kick_pdaemon(); /* ouch */
1155 
1156 	/* first we must be within the limit */
1157  limitagain:
1158 	if (rump_physmemlimit != RUMPMEM_UNLIMITED) {
1159 		newmem = atomic_add_long_nv(&curphysmem, howmuch);
1160 		if (newmem > rump_physmemlimit) {
1161 			newmem = atomic_add_long_nv(&curphysmem, -howmuch);
1162 			if (!waitok) {
1163 				return NULL;
1164 			}
1165 			uvm_wait(wmsg);
1166 			goto limitagain;
1167 		}
1168 	}
1169 
1170 	/* second, we must get something from the backend */
1171  again:
1172 	error = rumpuser_malloc(howmuch, alignment, &rv);
1173 	if (__predict_false(error && waitok)) {
1174 		uvm_wait(wmsg);
1175 		goto again;
1176 	}
1177 
1178 	return rv;
1179 }
1180 
1181 void
1182 rump_hyperfree(void *what, size_t size)
1183 {
1184 
1185 	if (rump_physmemlimit != RUMPMEM_UNLIMITED) {
1186 		atomic_add_long(&curphysmem, -size);
1187 	}
1188 	rumpuser_free(what, size);
1189 }
1190