xref: /netbsd-src/sys/kern/subr_vmem.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: subr_vmem.c,v 1.57 2009/03/18 10:22:42 cegger Exp $	*/
2 
3 /*-
4  * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi,
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * reference:
31  * -	Magazines and Vmem: Extending the Slab Allocator
32  *	to Many CPUs and Arbitrary Resources
33  *	http://www.usenix.org/event/usenix01/bonwick.html
34  *
35  * todo:
36  * -	decide how to import segments for vmem_xalloc.
37  * -	don't rely on malloc(9).
38  */
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: subr_vmem.c,v 1.57 2009/03/18 10:22:42 cegger Exp $");
42 
43 #if defined(_KERNEL)
44 #include "opt_ddb.h"
45 #define	QCACHE
46 #endif /* defined(_KERNEL) */
47 
48 #include <sys/param.h>
49 #include <sys/hash.h>
50 #include <sys/queue.h>
51 
52 #if defined(_KERNEL)
53 #include <sys/systm.h>
54 #include <sys/kernel.h>	/* hz */
55 #include <sys/callout.h>
56 #include <sys/malloc.h>
57 #include <sys/once.h>
58 #include <sys/pool.h>
59 #include <sys/vmem.h>
60 #include <sys/workqueue.h>
61 #else /* defined(_KERNEL) */
62 #include "../sys/vmem.h"
63 #endif /* defined(_KERNEL) */
64 
65 #if defined(_KERNEL)
66 #define	LOCK_DECL(name)		\
67     kmutex_t name; char lockpad[COHERENCY_UNIT - sizeof(kmutex_t)]
68 #else /* defined(_KERNEL) */
69 #include <errno.h>
70 #include <assert.h>
71 #include <stdlib.h>
72 
73 #define	UNITTEST
74 #define	KASSERT(a)		assert(a)
75 #define	LOCK_DECL(name)		/* nothing */
76 #define	mutex_init(a, b, c)	/* nothing */
77 #define	mutex_destroy(a)	/* nothing */
78 #define	mutex_enter(a)		/* nothing */
79 #define	mutex_tryenter(a)	true
80 #define	mutex_exit(a)		/* nothing */
81 #define	mutex_owned(a)		/* nothing */
82 #define	ASSERT_SLEEPABLE()	/* nothing */
83 #define	panic(...)		printf(__VA_ARGS__); abort()
84 #endif /* defined(_KERNEL) */
85 
86 struct vmem;
87 struct vmem_btag;
88 
89 #if defined(VMEM_SANITY)
90 static void vmem_check(vmem_t *);
91 #else /* defined(VMEM_SANITY) */
92 #define vmem_check(vm)	/* nothing */
93 #endif /* defined(VMEM_SANITY) */
94 
95 #define	VMEM_MAXORDER		(sizeof(vmem_size_t) * CHAR_BIT)
96 
97 #define	VMEM_HASHSIZE_MIN	1	/* XXX */
98 #define	VMEM_HASHSIZE_MAX	65536	/* XXX */
99 #define	VMEM_HASHSIZE_INIT	128
100 
101 #define	VM_FITMASK	(VM_BESTFIT | VM_INSTANTFIT)
102 
103 CIRCLEQ_HEAD(vmem_seglist, vmem_btag);
104 LIST_HEAD(vmem_freelist, vmem_btag);
105 LIST_HEAD(vmem_hashlist, vmem_btag);
106 
107 #if defined(QCACHE)
108 #define	VMEM_QCACHE_IDX_MAX	32
109 
110 #define	QC_NAME_MAX	16
111 
112 struct qcache {
113 	pool_cache_t qc_cache;
114 	vmem_t *qc_vmem;
115 	char qc_name[QC_NAME_MAX];
116 };
117 typedef struct qcache qcache_t;
118 #define	QC_POOL_TO_QCACHE(pool)	((qcache_t *)(pool->pr_qcache))
119 #endif /* defined(QCACHE) */
120 
121 /* vmem arena */
122 struct vmem {
123 	LOCK_DECL(vm_lock);
124 	vmem_addr_t (*vm_allocfn)(vmem_t *, vmem_size_t, vmem_size_t *,
125 	    vm_flag_t);
126 	void (*vm_freefn)(vmem_t *, vmem_addr_t, vmem_size_t);
127 	vmem_t *vm_source;
128 	struct vmem_seglist vm_seglist;
129 	struct vmem_freelist vm_freelist[VMEM_MAXORDER];
130 	size_t vm_hashsize;
131 	size_t vm_nbusytag;
132 	struct vmem_hashlist *vm_hashlist;
133 	size_t vm_quantum_mask;
134 	int vm_quantum_shift;
135 	const char *vm_name;
136 	LIST_ENTRY(vmem) vm_alllist;
137 
138 #if defined(QCACHE)
139 	/* quantum cache */
140 	size_t vm_qcache_max;
141 	struct pool_allocator vm_qcache_allocator;
142 	qcache_t vm_qcache_store[VMEM_QCACHE_IDX_MAX];
143 	qcache_t *vm_qcache[VMEM_QCACHE_IDX_MAX];
144 #endif /* defined(QCACHE) */
145 };
146 
147 #define	VMEM_LOCK(vm)		mutex_enter(&vm->vm_lock)
148 #define	VMEM_TRYLOCK(vm)	mutex_tryenter(&vm->vm_lock)
149 #define	VMEM_UNLOCK(vm)		mutex_exit(&vm->vm_lock)
150 #define	VMEM_LOCK_INIT(vm, ipl)	mutex_init(&vm->vm_lock, MUTEX_DEFAULT, ipl)
151 #define	VMEM_LOCK_DESTROY(vm)	mutex_destroy(&vm->vm_lock)
152 #define	VMEM_ASSERT_LOCKED(vm)	KASSERT(mutex_owned(&vm->vm_lock))
153 
154 /* boundary tag */
155 struct vmem_btag {
156 	CIRCLEQ_ENTRY(vmem_btag) bt_seglist;
157 	union {
158 		LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */
159 		LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */
160 	} bt_u;
161 #define	bt_hashlist	bt_u.u_hashlist
162 #define	bt_freelist	bt_u.u_freelist
163 	vmem_addr_t bt_start;
164 	vmem_size_t bt_size;
165 	int bt_type;
166 };
167 
168 #define	BT_TYPE_SPAN		1
169 #define	BT_TYPE_SPAN_STATIC	2
170 #define	BT_TYPE_FREE		3
171 #define	BT_TYPE_BUSY		4
172 #define	BT_ISSPAN_P(bt)	((bt)->bt_type <= BT_TYPE_SPAN_STATIC)
173 
174 #define	BT_END(bt)	((bt)->bt_start + (bt)->bt_size)
175 
176 typedef struct vmem_btag bt_t;
177 
178 /* ---- misc */
179 
180 #define	VMEM_ALIGNUP(addr, align) \
181 	(-(-(addr) & -(align)))
182 #define	VMEM_CROSS_P(addr1, addr2, boundary) \
183 	((((addr1) ^ (addr2)) & -(boundary)) != 0)
184 
185 #define	ORDER2SIZE(order)	((vmem_size_t)1 << (order))
186 
187 static int
188 calc_order(vmem_size_t size)
189 {
190 	vmem_size_t target;
191 	int i;
192 
193 	KASSERT(size != 0);
194 
195 	i = 0;
196 	target = size >> 1;
197 	while (ORDER2SIZE(i) <= target) {
198 		i++;
199 	}
200 
201 	KASSERT(ORDER2SIZE(i) <= size);
202 	KASSERT(size < ORDER2SIZE(i + 1) || ORDER2SIZE(i + 1) < ORDER2SIZE(i));
203 
204 	return i;
205 }
206 
207 #if defined(_KERNEL)
208 static MALLOC_DEFINE(M_VMEM, "vmem", "vmem");
209 #endif /* defined(_KERNEL) */
210 
211 static void *
212 xmalloc(size_t sz, vm_flag_t flags)
213 {
214 
215 #if defined(_KERNEL)
216 	return malloc(sz, M_VMEM,
217 	    M_CANFAIL | ((flags & VM_SLEEP) ? M_WAITOK : M_NOWAIT));
218 #else /* defined(_KERNEL) */
219 	return malloc(sz);
220 #endif /* defined(_KERNEL) */
221 }
222 
223 static void
224 xfree(void *p)
225 {
226 
227 #if defined(_KERNEL)
228 	return free(p, M_VMEM);
229 #else /* defined(_KERNEL) */
230 	return free(p);
231 #endif /* defined(_KERNEL) */
232 }
233 
234 /* ---- boundary tag */
235 
236 #if defined(_KERNEL)
237 static struct pool_cache bt_cache;
238 #endif /* defined(_KERNEL) */
239 
240 static bt_t *
241 bt_alloc(vmem_t *vm, vm_flag_t flags)
242 {
243 	bt_t *bt;
244 
245 #if defined(_KERNEL)
246 	bt = pool_cache_get(&bt_cache,
247 	    (flags & VM_SLEEP) != 0 ? PR_WAITOK : PR_NOWAIT);
248 #else /* defined(_KERNEL) */
249 	bt = malloc(sizeof *bt);
250 #endif /* defined(_KERNEL) */
251 
252 	return bt;
253 }
254 
255 static void
256 bt_free(vmem_t *vm, bt_t *bt)
257 {
258 
259 #if defined(_KERNEL)
260 	pool_cache_put(&bt_cache, bt);
261 #else /* defined(_KERNEL) */
262 	free(bt);
263 #endif /* defined(_KERNEL) */
264 }
265 
266 /*
267  * freelist[0] ... [1, 1]
268  * freelist[1] ... [2, 3]
269  * freelist[2] ... [4, 7]
270  * freelist[3] ... [8, 15]
271  *  :
272  * freelist[n] ... [(1 << n), (1 << (n + 1)) - 1]
273  *  :
274  */
275 
276 static struct vmem_freelist *
277 bt_freehead_tofree(vmem_t *vm, vmem_size_t size)
278 {
279 	const vmem_size_t qsize = size >> vm->vm_quantum_shift;
280 	int idx;
281 
282 	KASSERT((size & vm->vm_quantum_mask) == 0);
283 	KASSERT(size != 0);
284 
285 	idx = calc_order(qsize);
286 	KASSERT(idx >= 0);
287 	KASSERT(idx < VMEM_MAXORDER);
288 
289 	return &vm->vm_freelist[idx];
290 }
291 
292 static struct vmem_freelist *
293 bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, vm_flag_t strat)
294 {
295 	const vmem_size_t qsize = size >> vm->vm_quantum_shift;
296 	int idx;
297 
298 	KASSERT((size & vm->vm_quantum_mask) == 0);
299 	KASSERT(size != 0);
300 
301 	idx = calc_order(qsize);
302 	if (strat == VM_INSTANTFIT && ORDER2SIZE(idx) != qsize) {
303 		idx++;
304 		/* check too large request? */
305 	}
306 	KASSERT(idx >= 0);
307 	KASSERT(idx < VMEM_MAXORDER);
308 
309 	return &vm->vm_freelist[idx];
310 }
311 
312 /* ---- boundary tag hash */
313 
314 static struct vmem_hashlist *
315 bt_hashhead(vmem_t *vm, vmem_addr_t addr)
316 {
317 	struct vmem_hashlist *list;
318 	unsigned int hash;
319 
320 	hash = hash32_buf(&addr, sizeof(addr), HASH32_BUF_INIT);
321 	list = &vm->vm_hashlist[hash % vm->vm_hashsize];
322 
323 	return list;
324 }
325 
326 static bt_t *
327 bt_lookupbusy(vmem_t *vm, vmem_addr_t addr)
328 {
329 	struct vmem_hashlist *list;
330 	bt_t *bt;
331 
332 	list = bt_hashhead(vm, addr);
333 	LIST_FOREACH(bt, list, bt_hashlist) {
334 		if (bt->bt_start == addr) {
335 			break;
336 		}
337 	}
338 
339 	return bt;
340 }
341 
342 static void
343 bt_rembusy(vmem_t *vm, bt_t *bt)
344 {
345 
346 	KASSERT(vm->vm_nbusytag > 0);
347 	vm->vm_nbusytag--;
348 	LIST_REMOVE(bt, bt_hashlist);
349 }
350 
351 static void
352 bt_insbusy(vmem_t *vm, bt_t *bt)
353 {
354 	struct vmem_hashlist *list;
355 
356 	KASSERT(bt->bt_type == BT_TYPE_BUSY);
357 
358 	list = bt_hashhead(vm, bt->bt_start);
359 	LIST_INSERT_HEAD(list, bt, bt_hashlist);
360 	vm->vm_nbusytag++;
361 }
362 
363 /* ---- boundary tag list */
364 
365 static void
366 bt_remseg(vmem_t *vm, bt_t *bt)
367 {
368 
369 	CIRCLEQ_REMOVE(&vm->vm_seglist, bt, bt_seglist);
370 }
371 
372 static void
373 bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev)
374 {
375 
376 	CIRCLEQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist);
377 }
378 
379 static void
380 bt_insseg_tail(vmem_t *vm, bt_t *bt)
381 {
382 
383 	CIRCLEQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist);
384 }
385 
386 static void
387 bt_remfree(vmem_t *vm, bt_t *bt)
388 {
389 
390 	KASSERT(bt->bt_type == BT_TYPE_FREE);
391 
392 	LIST_REMOVE(bt, bt_freelist);
393 }
394 
395 static void
396 bt_insfree(vmem_t *vm, bt_t *bt)
397 {
398 	struct vmem_freelist *list;
399 
400 	list = bt_freehead_tofree(vm, bt->bt_size);
401 	LIST_INSERT_HEAD(list, bt, bt_freelist);
402 }
403 
404 /* ---- vmem internal functions */
405 
406 #if defined(_KERNEL)
407 static kmutex_t vmem_list_lock;
408 static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list);
409 #endif /* defined(_KERNEL) */
410 
411 #if defined(QCACHE)
412 static inline vm_flag_t
413 prf_to_vmf(int prflags)
414 {
415 	vm_flag_t vmflags;
416 
417 	KASSERT((prflags & ~(PR_LIMITFAIL | PR_WAITOK | PR_NOWAIT)) == 0);
418 	if ((prflags & PR_WAITOK) != 0) {
419 		vmflags = VM_SLEEP;
420 	} else {
421 		vmflags = VM_NOSLEEP;
422 	}
423 	return vmflags;
424 }
425 
426 static inline int
427 vmf_to_prf(vm_flag_t vmflags)
428 {
429 	int prflags;
430 
431 	if ((vmflags & VM_SLEEP) != 0) {
432 		prflags = PR_WAITOK;
433 	} else {
434 		prflags = PR_NOWAIT;
435 	}
436 	return prflags;
437 }
438 
439 static size_t
440 qc_poolpage_size(size_t qcache_max)
441 {
442 	int i;
443 
444 	for (i = 0; ORDER2SIZE(i) <= qcache_max * 3; i++) {
445 		/* nothing */
446 	}
447 	return ORDER2SIZE(i);
448 }
449 
450 static void *
451 qc_poolpage_alloc(struct pool *pool, int prflags)
452 {
453 	qcache_t *qc = QC_POOL_TO_QCACHE(pool);
454 	vmem_t *vm = qc->qc_vmem;
455 
456 	return (void *)vmem_alloc(vm, pool->pr_alloc->pa_pagesz,
457 	    prf_to_vmf(prflags) | VM_INSTANTFIT);
458 }
459 
460 static void
461 qc_poolpage_free(struct pool *pool, void *addr)
462 {
463 	qcache_t *qc = QC_POOL_TO_QCACHE(pool);
464 	vmem_t *vm = qc->qc_vmem;
465 
466 	vmem_free(vm, (vmem_addr_t)addr, pool->pr_alloc->pa_pagesz);
467 }
468 
469 static void
470 qc_init(vmem_t *vm, size_t qcache_max, int ipl)
471 {
472 	qcache_t *prevqc;
473 	struct pool_allocator *pa;
474 	int qcache_idx_max;
475 	int i;
476 
477 	KASSERT((qcache_max & vm->vm_quantum_mask) == 0);
478 	if (qcache_max > (VMEM_QCACHE_IDX_MAX << vm->vm_quantum_shift)) {
479 		qcache_max = VMEM_QCACHE_IDX_MAX << vm->vm_quantum_shift;
480 	}
481 	vm->vm_qcache_max = qcache_max;
482 	pa = &vm->vm_qcache_allocator;
483 	memset(pa, 0, sizeof(*pa));
484 	pa->pa_alloc = qc_poolpage_alloc;
485 	pa->pa_free = qc_poolpage_free;
486 	pa->pa_pagesz = qc_poolpage_size(qcache_max);
487 
488 	qcache_idx_max = qcache_max >> vm->vm_quantum_shift;
489 	prevqc = NULL;
490 	for (i = qcache_idx_max; i > 0; i--) {
491 		qcache_t *qc = &vm->vm_qcache_store[i - 1];
492 		size_t size = i << vm->vm_quantum_shift;
493 
494 		qc->qc_vmem = vm;
495 		snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu",
496 		    vm->vm_name, size);
497 		qc->qc_cache = pool_cache_init(size,
498 		    ORDER2SIZE(vm->vm_quantum_shift), 0,
499 		    PR_NOALIGN | PR_NOTOUCH /* XXX */,
500 		    qc->qc_name, pa, ipl, NULL, NULL, NULL);
501 		KASSERT(qc->qc_cache != NULL);	/* XXX */
502 		if (prevqc != NULL &&
503 		    qc->qc_cache->pc_pool.pr_itemsperpage ==
504 		    prevqc->qc_cache->pc_pool.pr_itemsperpage) {
505 			pool_cache_destroy(qc->qc_cache);
506 			vm->vm_qcache[i - 1] = prevqc;
507 			continue;
508 		}
509 		qc->qc_cache->pc_pool.pr_qcache = qc;
510 		vm->vm_qcache[i - 1] = qc;
511 		prevqc = qc;
512 	}
513 }
514 
515 static void
516 qc_destroy(vmem_t *vm)
517 {
518 	const qcache_t *prevqc;
519 	int i;
520 	int qcache_idx_max;
521 
522 	qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
523 	prevqc = NULL;
524 	for (i = 0; i < qcache_idx_max; i++) {
525 		qcache_t *qc = vm->vm_qcache[i];
526 
527 		if (prevqc == qc) {
528 			continue;
529 		}
530 		pool_cache_destroy(qc->qc_cache);
531 		prevqc = qc;
532 	}
533 }
534 
535 static bool
536 qc_reap(vmem_t *vm)
537 {
538 	const qcache_t *prevqc;
539 	int i;
540 	int qcache_idx_max;
541 	bool didsomething = false;
542 
543 	qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
544 	prevqc = NULL;
545 	for (i = 0; i < qcache_idx_max; i++) {
546 		qcache_t *qc = vm->vm_qcache[i];
547 
548 		if (prevqc == qc) {
549 			continue;
550 		}
551 		if (pool_cache_reclaim(qc->qc_cache) != 0) {
552 			didsomething = true;
553 		}
554 		prevqc = qc;
555 	}
556 
557 	return didsomething;
558 }
559 #endif /* defined(QCACHE) */
560 
561 #if defined(_KERNEL)
562 static int
563 vmem_init(void)
564 {
565 
566 	mutex_init(&vmem_list_lock, MUTEX_DEFAULT, IPL_NONE);
567 	pool_cache_bootstrap(&bt_cache, sizeof(bt_t), 0, 0, 0, "vmembt",
568 	    NULL, IPL_VM, NULL, NULL, NULL);
569 	return 0;
570 }
571 #endif /* defined(_KERNEL) */
572 
573 static vmem_addr_t
574 vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, vm_flag_t flags,
575     int spanbttype)
576 {
577 	bt_t *btspan;
578 	bt_t *btfree;
579 
580 	KASSERT((flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
581 	KASSERT((~flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
582 	KASSERT(spanbttype == BT_TYPE_SPAN || spanbttype == BT_TYPE_SPAN_STATIC);
583 
584 	btspan = bt_alloc(vm, flags);
585 	if (btspan == NULL) {
586 		return VMEM_ADDR_NULL;
587 	}
588 	btfree = bt_alloc(vm, flags);
589 	if (btfree == NULL) {
590 		bt_free(vm, btspan);
591 		return VMEM_ADDR_NULL;
592 	}
593 
594 	btspan->bt_type = spanbttype;
595 	btspan->bt_start = addr;
596 	btspan->bt_size = size;
597 
598 	btfree->bt_type = BT_TYPE_FREE;
599 	btfree->bt_start = addr;
600 	btfree->bt_size = size;
601 
602 	VMEM_LOCK(vm);
603 	bt_insseg_tail(vm, btspan);
604 	bt_insseg(vm, btfree, btspan);
605 	bt_insfree(vm, btfree);
606 	VMEM_UNLOCK(vm);
607 
608 	return addr;
609 }
610 
611 static void
612 vmem_destroy1(vmem_t *vm)
613 {
614 
615 #if defined(QCACHE)
616 	qc_destroy(vm);
617 #endif /* defined(QCACHE) */
618 	if (vm->vm_hashlist != NULL) {
619 		int i;
620 
621 		for (i = 0; i < vm->vm_hashsize; i++) {
622 			bt_t *bt;
623 
624 			while ((bt = LIST_FIRST(&vm->vm_hashlist[i])) != NULL) {
625 				KASSERT(bt->bt_type == BT_TYPE_SPAN_STATIC);
626 				bt_free(vm, bt);
627 			}
628 		}
629 		xfree(vm->vm_hashlist);
630 	}
631 	VMEM_LOCK_DESTROY(vm);
632 	xfree(vm);
633 }
634 
635 static int
636 vmem_import(vmem_t *vm, vmem_size_t size, vm_flag_t flags)
637 {
638 	vmem_addr_t addr;
639 
640 	if (vm->vm_allocfn == NULL) {
641 		return EINVAL;
642 	}
643 
644 	addr = (*vm->vm_allocfn)(vm->vm_source, size, &size, flags);
645 	if (addr == VMEM_ADDR_NULL) {
646 		return ENOMEM;
647 	}
648 
649 	if (vmem_add1(vm, addr, size, flags, BT_TYPE_SPAN) == VMEM_ADDR_NULL) {
650 		(*vm->vm_freefn)(vm->vm_source, addr, size);
651 		return ENOMEM;
652 	}
653 
654 	return 0;
655 }
656 
657 static int
658 vmem_rehash(vmem_t *vm, size_t newhashsize, vm_flag_t flags)
659 {
660 	bt_t *bt;
661 	int i;
662 	struct vmem_hashlist *newhashlist;
663 	struct vmem_hashlist *oldhashlist;
664 	size_t oldhashsize;
665 
666 	KASSERT(newhashsize > 0);
667 
668 	newhashlist =
669 	    xmalloc(sizeof(struct vmem_hashlist *) * newhashsize, flags);
670 	if (newhashlist == NULL) {
671 		return ENOMEM;
672 	}
673 	for (i = 0; i < newhashsize; i++) {
674 		LIST_INIT(&newhashlist[i]);
675 	}
676 
677 	if (!VMEM_TRYLOCK(vm)) {
678 		xfree(newhashlist);
679 		return EBUSY;
680 	}
681 	oldhashlist = vm->vm_hashlist;
682 	oldhashsize = vm->vm_hashsize;
683 	vm->vm_hashlist = newhashlist;
684 	vm->vm_hashsize = newhashsize;
685 	if (oldhashlist == NULL) {
686 		VMEM_UNLOCK(vm);
687 		return 0;
688 	}
689 	for (i = 0; i < oldhashsize; i++) {
690 		while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) {
691 			bt_rembusy(vm, bt); /* XXX */
692 			bt_insbusy(vm, bt);
693 		}
694 	}
695 	VMEM_UNLOCK(vm);
696 
697 	xfree(oldhashlist);
698 
699 	return 0;
700 }
701 
702 /*
703  * vmem_fit: check if a bt can satisfy the given restrictions.
704  */
705 
706 static vmem_addr_t
707 vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align, vmem_size_t phase,
708     vmem_size_t nocross, vmem_addr_t minaddr, vmem_addr_t maxaddr)
709 {
710 	vmem_addr_t start;
711 	vmem_addr_t end;
712 
713 	KASSERT(bt->bt_size >= size);
714 
715 	/*
716 	 * XXX assumption: vmem_addr_t and vmem_size_t are
717 	 * unsigned integer of the same size.
718 	 */
719 
720 	start = bt->bt_start;
721 	if (start < minaddr) {
722 		start = minaddr;
723 	}
724 	end = BT_END(bt);
725 	if (end > maxaddr - 1) {
726 		end = maxaddr - 1;
727 	}
728 	if (start >= end) {
729 		return VMEM_ADDR_NULL;
730 	}
731 
732 	start = VMEM_ALIGNUP(start - phase, align) + phase;
733 	if (start < bt->bt_start) {
734 		start += align;
735 	}
736 	if (VMEM_CROSS_P(start, start + size - 1, nocross)) {
737 		KASSERT(align < nocross);
738 		start = VMEM_ALIGNUP(start - phase, nocross) + phase;
739 	}
740 	if (start < end && end - start >= size) {
741 		KASSERT((start & (align - 1)) == phase);
742 		KASSERT(!VMEM_CROSS_P(start, start + size - 1, nocross));
743 		KASSERT(minaddr <= start);
744 		KASSERT(maxaddr == 0 || start + size <= maxaddr);
745 		KASSERT(bt->bt_start <= start);
746 		KASSERT(start + size <= BT_END(bt));
747 		return start;
748 	}
749 	return VMEM_ADDR_NULL;
750 }
751 
752 /* ---- vmem API */
753 
754 /*
755  * vmem_create: create an arena.
756  *
757  * => must not be called from interrupt context.
758  */
759 
760 vmem_t *
761 vmem_create(const char *name, vmem_addr_t base, vmem_size_t size,
762     vmem_size_t quantum,
763     vmem_addr_t (*allocfn)(vmem_t *, vmem_size_t, vmem_size_t *, vm_flag_t),
764     void (*freefn)(vmem_t *, vmem_addr_t, vmem_size_t),
765     vmem_t *source, vmem_size_t qcache_max, vm_flag_t flags,
766     int ipl)
767 {
768 	vmem_t *vm;
769 	int i;
770 #if defined(_KERNEL)
771 	static ONCE_DECL(control);
772 #endif /* defined(_KERNEL) */
773 
774 	KASSERT((flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
775 	KASSERT((~flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
776 
777 #if defined(_KERNEL)
778 	if (RUN_ONCE(&control, vmem_init)) {
779 		return NULL;
780 	}
781 #endif /* defined(_KERNEL) */
782 	vm = xmalloc(sizeof(*vm), flags);
783 	if (vm == NULL) {
784 		return NULL;
785 	}
786 
787 	VMEM_LOCK_INIT(vm, ipl);
788 	vm->vm_name = name;
789 	vm->vm_quantum_mask = quantum - 1;
790 	vm->vm_quantum_shift = calc_order(quantum);
791 	KASSERT(ORDER2SIZE(vm->vm_quantum_shift) == quantum);
792 	vm->vm_allocfn = allocfn;
793 	vm->vm_freefn = freefn;
794 	vm->vm_source = source;
795 	vm->vm_nbusytag = 0;
796 #if defined(QCACHE)
797 	qc_init(vm, qcache_max, ipl);
798 #endif /* defined(QCACHE) */
799 
800 	CIRCLEQ_INIT(&vm->vm_seglist);
801 	for (i = 0; i < VMEM_MAXORDER; i++) {
802 		LIST_INIT(&vm->vm_freelist[i]);
803 	}
804 	vm->vm_hashlist = NULL;
805 	if (vmem_rehash(vm, VMEM_HASHSIZE_INIT, flags)) {
806 		vmem_destroy1(vm);
807 		return NULL;
808 	}
809 
810 	if (size != 0) {
811 		if (vmem_add(vm, base, size, flags) == 0) {
812 			vmem_destroy1(vm);
813 			return NULL;
814 		}
815 	}
816 
817 #if defined(_KERNEL)
818 	mutex_enter(&vmem_list_lock);
819 	LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist);
820 	mutex_exit(&vmem_list_lock);
821 #endif /* defined(_KERNEL) */
822 
823 	return vm;
824 }
825 
826 void
827 vmem_destroy(vmem_t *vm)
828 {
829 
830 #if defined(_KERNEL)
831 	mutex_enter(&vmem_list_lock);
832 	LIST_REMOVE(vm, vm_alllist);
833 	mutex_exit(&vmem_list_lock);
834 #endif /* defined(_KERNEL) */
835 
836 	vmem_destroy1(vm);
837 }
838 
839 vmem_size_t
840 vmem_roundup_size(vmem_t *vm, vmem_size_t size)
841 {
842 
843 	return (size + vm->vm_quantum_mask) & ~vm->vm_quantum_mask;
844 }
845 
846 /*
847  * vmem_alloc:
848  *
849  * => caller must ensure appropriate spl,
850  *    if the arena can be accessed from interrupt context.
851  */
852 
853 vmem_addr_t
854 vmem_alloc(vmem_t *vm, vmem_size_t size, vm_flag_t flags)
855 {
856 	const vm_flag_t strat __unused = flags & VM_FITMASK;
857 
858 	KASSERT((flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
859 	KASSERT((~flags & (VM_SLEEP|VM_NOSLEEP)) != 0);
860 
861 	KASSERT(size > 0);
862 	KASSERT(strat == VM_BESTFIT || strat == VM_INSTANTFIT);
863 	if ((flags & VM_SLEEP) != 0) {
864 		ASSERT_SLEEPABLE();
865 	}
866 
867 #if defined(QCACHE)
868 	if (size <= vm->vm_qcache_max) {
869 		int qidx = (size + vm->vm_quantum_mask) >> vm->vm_quantum_shift;
870 		qcache_t *qc = vm->vm_qcache[qidx - 1];
871 
872 		return (vmem_addr_t)pool_cache_get(qc->qc_cache,
873 		    vmf_to_prf(flags));
874 	}
875 #endif /* defined(QCACHE) */
876 
877 	return vmem_xalloc(vm, size, 0, 0, 0, 0, 0, flags);
878 }
879 
880 vmem_addr_t
881 vmem_xalloc(vmem_t *vm, vmem_size_t size0, vmem_size_t align, vmem_size_t phase,
882     vmem_size_t nocross, vmem_addr_t minaddr, vmem_addr_t maxaddr,
883     vm_flag_t flags)
884 {
885 	struct vmem_freelist *list;
886 	struct vmem_freelist *first;
887 	struct vmem_freelist *end;
888 	bt_t *bt;
889 	bt_t *btnew;
890 	bt_t *btnew2;
891 	const vmem_size_t size = vmem_roundup_size(vm, size0);
892 	vm_flag_t strat = flags & VM_FITMASK;
893 	vmem_addr_t start;
894 
895 	KASSERT(size0 > 0);
896 	KASSERT(size > 0);
897 	KASSERT(strat == VM_BESTFIT || strat == VM_INSTANTFIT);
898 	if ((flags & VM_SLEEP) != 0) {
899 		ASSERT_SLEEPABLE();
900 	}
901 	KASSERT((align & vm->vm_quantum_mask) == 0);
902 	KASSERT((align & (align - 1)) == 0);
903 	KASSERT((phase & vm->vm_quantum_mask) == 0);
904 	KASSERT((nocross & vm->vm_quantum_mask) == 0);
905 	KASSERT((nocross & (nocross - 1)) == 0);
906 	KASSERT((align == 0 && phase == 0) || phase < align);
907 	KASSERT(nocross == 0 || nocross >= size);
908 	KASSERT(maxaddr == 0 || minaddr < maxaddr);
909 	KASSERT(!VMEM_CROSS_P(phase, phase + size - 1, nocross));
910 
911 	if (align == 0) {
912 		align = vm->vm_quantum_mask + 1;
913 	}
914 	btnew = bt_alloc(vm, flags);
915 	if (btnew == NULL) {
916 		return VMEM_ADDR_NULL;
917 	}
918 	btnew2 = bt_alloc(vm, flags); /* XXX not necessary if no restrictions */
919 	if (btnew2 == NULL) {
920 		bt_free(vm, btnew);
921 		return VMEM_ADDR_NULL;
922 	}
923 
924 retry_strat:
925 	first = bt_freehead_toalloc(vm, size, strat);
926 	end = &vm->vm_freelist[VMEM_MAXORDER];
927 retry:
928 	bt = NULL;
929 	VMEM_LOCK(vm);
930 	vmem_check(vm);
931 	if (strat == VM_INSTANTFIT) {
932 		for (list = first; list < end; list++) {
933 			bt = LIST_FIRST(list);
934 			if (bt != NULL) {
935 				start = vmem_fit(bt, size, align, phase,
936 				    nocross, minaddr, maxaddr);
937 				if (start != VMEM_ADDR_NULL) {
938 					goto gotit;
939 				}
940 			}
941 		}
942 	} else { /* VM_BESTFIT */
943 		for (list = first; list < end; list++) {
944 			LIST_FOREACH(bt, list, bt_freelist) {
945 				if (bt->bt_size >= size) {
946 					start = vmem_fit(bt, size, align, phase,
947 					    nocross, minaddr, maxaddr);
948 					if (start != VMEM_ADDR_NULL) {
949 						goto gotit;
950 					}
951 				}
952 			}
953 		}
954 	}
955 	VMEM_UNLOCK(vm);
956 #if 1
957 	if (strat == VM_INSTANTFIT) {
958 		strat = VM_BESTFIT;
959 		goto retry_strat;
960 	}
961 #endif
962 	if (align != vm->vm_quantum_mask + 1 || phase != 0 ||
963 	    nocross != 0 || minaddr != 0 || maxaddr != 0) {
964 
965 		/*
966 		 * XXX should try to import a region large enough to
967 		 * satisfy restrictions?
968 		 */
969 
970 		goto fail;
971 	}
972 	if (vmem_import(vm, size, flags) == 0) {
973 		goto retry;
974 	}
975 	/* XXX */
976 fail:
977 	bt_free(vm, btnew);
978 	bt_free(vm, btnew2);
979 	return VMEM_ADDR_NULL;
980 
981 gotit:
982 	KASSERT(bt->bt_type == BT_TYPE_FREE);
983 	KASSERT(bt->bt_size >= size);
984 	bt_remfree(vm, bt);
985 	vmem_check(vm);
986 	if (bt->bt_start != start) {
987 		btnew2->bt_type = BT_TYPE_FREE;
988 		btnew2->bt_start = bt->bt_start;
989 		btnew2->bt_size = start - bt->bt_start;
990 		bt->bt_start = start;
991 		bt->bt_size -= btnew2->bt_size;
992 		bt_insfree(vm, btnew2);
993 		bt_insseg(vm, btnew2, CIRCLEQ_PREV(bt, bt_seglist));
994 		btnew2 = NULL;
995 		vmem_check(vm);
996 	}
997 	KASSERT(bt->bt_start == start);
998 	if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) {
999 		/* split */
1000 		btnew->bt_type = BT_TYPE_BUSY;
1001 		btnew->bt_start = bt->bt_start;
1002 		btnew->bt_size = size;
1003 		bt->bt_start = bt->bt_start + size;
1004 		bt->bt_size -= size;
1005 		bt_insfree(vm, bt);
1006 		bt_insseg(vm, btnew, CIRCLEQ_PREV(bt, bt_seglist));
1007 		bt_insbusy(vm, btnew);
1008 		vmem_check(vm);
1009 		VMEM_UNLOCK(vm);
1010 	} else {
1011 		bt->bt_type = BT_TYPE_BUSY;
1012 		bt_insbusy(vm, bt);
1013 		vmem_check(vm);
1014 		VMEM_UNLOCK(vm);
1015 		bt_free(vm, btnew);
1016 		btnew = bt;
1017 	}
1018 	if (btnew2 != NULL) {
1019 		bt_free(vm, btnew2);
1020 	}
1021 	KASSERT(btnew->bt_size >= size);
1022 	btnew->bt_type = BT_TYPE_BUSY;
1023 
1024 	return btnew->bt_start;
1025 }
1026 
1027 /*
1028  * vmem_free:
1029  *
1030  * => caller must ensure appropriate spl,
1031  *    if the arena can be accessed from interrupt context.
1032  */
1033 
1034 void
1035 vmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
1036 {
1037 
1038 	KASSERT(addr != VMEM_ADDR_NULL);
1039 	KASSERT(size > 0);
1040 
1041 #if defined(QCACHE)
1042 	if (size <= vm->vm_qcache_max) {
1043 		int qidx = (size + vm->vm_quantum_mask) >> vm->vm_quantum_shift;
1044 		qcache_t *qc = vm->vm_qcache[qidx - 1];
1045 
1046 		return pool_cache_put(qc->qc_cache, (void *)addr);
1047 	}
1048 #endif /* defined(QCACHE) */
1049 
1050 	vmem_xfree(vm, addr, size);
1051 }
1052 
1053 void
1054 vmem_xfree(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
1055 {
1056 	bt_t *bt;
1057 	bt_t *t;
1058 
1059 	KASSERT(addr != VMEM_ADDR_NULL);
1060 	KASSERT(size > 0);
1061 
1062 	VMEM_LOCK(vm);
1063 
1064 	bt = bt_lookupbusy(vm, addr);
1065 	KASSERT(bt != NULL);
1066 	KASSERT(bt->bt_start == addr);
1067 	KASSERT(bt->bt_size == vmem_roundup_size(vm, size) ||
1068 	    bt->bt_size - vmem_roundup_size(vm, size) <= vm->vm_quantum_mask);
1069 	KASSERT(bt->bt_type == BT_TYPE_BUSY);
1070 	bt_rembusy(vm, bt);
1071 	bt->bt_type = BT_TYPE_FREE;
1072 
1073 	/* coalesce */
1074 	t = CIRCLEQ_NEXT(bt, bt_seglist);
1075 	if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1076 		KASSERT(BT_END(bt) == t->bt_start);
1077 		bt_remfree(vm, t);
1078 		bt_remseg(vm, t);
1079 		bt->bt_size += t->bt_size;
1080 		bt_free(vm, t);
1081 	}
1082 	t = CIRCLEQ_PREV(bt, bt_seglist);
1083 	if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1084 		KASSERT(BT_END(t) == bt->bt_start);
1085 		bt_remfree(vm, t);
1086 		bt_remseg(vm, t);
1087 		bt->bt_size += t->bt_size;
1088 		bt->bt_start = t->bt_start;
1089 		bt_free(vm, t);
1090 	}
1091 
1092 	t = CIRCLEQ_PREV(bt, bt_seglist);
1093 	KASSERT(t != NULL);
1094 	KASSERT(BT_ISSPAN_P(t) || t->bt_type == BT_TYPE_BUSY);
1095 	if (vm->vm_freefn != NULL && t->bt_type == BT_TYPE_SPAN &&
1096 	    t->bt_size == bt->bt_size) {
1097 		vmem_addr_t spanaddr;
1098 		vmem_size_t spansize;
1099 
1100 		KASSERT(t->bt_start == bt->bt_start);
1101 		spanaddr = bt->bt_start;
1102 		spansize = bt->bt_size;
1103 		bt_remseg(vm, bt);
1104 		bt_free(vm, bt);
1105 		bt_remseg(vm, t);
1106 		bt_free(vm, t);
1107 		VMEM_UNLOCK(vm);
1108 		(*vm->vm_freefn)(vm->vm_source, spanaddr, spansize);
1109 	} else {
1110 		bt_insfree(vm, bt);
1111 		VMEM_UNLOCK(vm);
1112 	}
1113 }
1114 
1115 /*
1116  * vmem_add:
1117  *
1118  * => caller must ensure appropriate spl,
1119  *    if the arena can be accessed from interrupt context.
1120  */
1121 
1122 vmem_addr_t
1123 vmem_add(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, vm_flag_t flags)
1124 {
1125 
1126 	return vmem_add1(vm, addr, size, flags, BT_TYPE_SPAN_STATIC);
1127 }
1128 
1129 /*
1130  * vmem_reap: reap unused resources.
1131  *
1132  * => return true if we successfully reaped something.
1133  */
1134 
1135 bool
1136 vmem_reap(vmem_t *vm)
1137 {
1138 	bool didsomething = false;
1139 
1140 #if defined(QCACHE)
1141 	didsomething = qc_reap(vm);
1142 #endif /* defined(QCACHE) */
1143 	return didsomething;
1144 }
1145 
1146 /* ---- rehash */
1147 
1148 #if defined(_KERNEL)
1149 static struct callout vmem_rehash_ch;
1150 static int vmem_rehash_interval;
1151 static struct workqueue *vmem_rehash_wq;
1152 static struct work vmem_rehash_wk;
1153 
1154 static void
1155 vmem_rehash_all(struct work *wk, void *dummy)
1156 {
1157 	vmem_t *vm;
1158 
1159 	KASSERT(wk == &vmem_rehash_wk);
1160 	mutex_enter(&vmem_list_lock);
1161 	LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1162 		size_t desired;
1163 		size_t current;
1164 
1165 		if (!VMEM_TRYLOCK(vm)) {
1166 			continue;
1167 		}
1168 		desired = vm->vm_nbusytag;
1169 		current = vm->vm_hashsize;
1170 		VMEM_UNLOCK(vm);
1171 
1172 		if (desired > VMEM_HASHSIZE_MAX) {
1173 			desired = VMEM_HASHSIZE_MAX;
1174 		} else if (desired < VMEM_HASHSIZE_MIN) {
1175 			desired = VMEM_HASHSIZE_MIN;
1176 		}
1177 		if (desired > current * 2 || desired * 2 < current) {
1178 			vmem_rehash(vm, desired, VM_NOSLEEP);
1179 		}
1180 	}
1181 	mutex_exit(&vmem_list_lock);
1182 
1183 	callout_schedule(&vmem_rehash_ch, vmem_rehash_interval);
1184 }
1185 
1186 static void
1187 vmem_rehash_all_kick(void *dummy)
1188 {
1189 
1190 	workqueue_enqueue(vmem_rehash_wq, &vmem_rehash_wk, NULL);
1191 }
1192 
1193 void
1194 vmem_rehash_start(void)
1195 {
1196 	int error;
1197 
1198 	error = workqueue_create(&vmem_rehash_wq, "vmem_rehash",
1199 	    vmem_rehash_all, NULL, PRI_VM, IPL_SOFTCLOCK, WQ_MPSAFE);
1200 	if (error) {
1201 		panic("%s: workqueue_create %d\n", __func__, error);
1202 	}
1203 	callout_init(&vmem_rehash_ch, CALLOUT_MPSAFE);
1204 	callout_setfunc(&vmem_rehash_ch, vmem_rehash_all_kick, NULL);
1205 
1206 	vmem_rehash_interval = hz * 10;
1207 	callout_schedule(&vmem_rehash_ch, vmem_rehash_interval);
1208 }
1209 #endif /* defined(_KERNEL) */
1210 
1211 /* ---- debug */
1212 
1213 #if defined(DDB) || defined(UNITTEST) || defined(VMEM_SANITY)
1214 
1215 static void bt_dump(const bt_t *, void (*)(const char *, ...));
1216 
1217 static const char *
1218 bt_type_string(int type)
1219 {
1220 	static const char * const table[] = {
1221 		[BT_TYPE_BUSY] = "busy",
1222 		[BT_TYPE_FREE] = "free",
1223 		[BT_TYPE_SPAN] = "span",
1224 		[BT_TYPE_SPAN_STATIC] = "static span",
1225 	};
1226 
1227 	if (type >= __arraycount(table)) {
1228 		return "BOGUS";
1229 	}
1230 	return table[type];
1231 }
1232 
1233 static void
1234 bt_dump(const bt_t *bt, void (*pr)(const char *, ...))
1235 {
1236 
1237 	(*pr)("\t%p: %" PRIu64 ", %" PRIu64 ", %d(%s)\n",
1238 	    bt, (uint64_t)bt->bt_start, (uint64_t)bt->bt_size,
1239 	    bt->bt_type, bt_type_string(bt->bt_type));
1240 }
1241 
1242 static void
1243 vmem_dump(const vmem_t *vm , void (*pr)(const char *, ...))
1244 {
1245 	const bt_t *bt;
1246 	int i;
1247 
1248 	(*pr)("vmem %p '%s'\n", vm, vm->vm_name);
1249 	CIRCLEQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1250 		bt_dump(bt, pr);
1251 	}
1252 
1253 	for (i = 0; i < VMEM_MAXORDER; i++) {
1254 		const struct vmem_freelist *fl = &vm->vm_freelist[i];
1255 
1256 		if (LIST_EMPTY(fl)) {
1257 			continue;
1258 		}
1259 
1260 		(*pr)("freelist[%d]\n", i);
1261 		LIST_FOREACH(bt, fl, bt_freelist) {
1262 			bt_dump(bt, pr);
1263 		}
1264 	}
1265 }
1266 
1267 #endif /* defined(DDB) || defined(UNITTEST) || defined(VMEM_SANITY) */
1268 
1269 #if defined(DDB)
1270 static bt_t *
1271 vmem_whatis_lookup(vmem_t *vm, uintptr_t addr)
1272 {
1273 	bt_t *bt;
1274 
1275 	CIRCLEQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1276 		if (BT_ISSPAN_P(bt)) {
1277 			continue;
1278 		}
1279 		if (bt->bt_start <= addr && addr < BT_END(bt)) {
1280 			return bt;
1281 		}
1282 	}
1283 
1284 	return NULL;
1285 }
1286 
1287 void
1288 vmem_whatis(uintptr_t addr, void (*pr)(const char *, ...))
1289 {
1290 	vmem_t *vm;
1291 
1292 	LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1293 		bt_t *bt;
1294 
1295 		bt = vmem_whatis_lookup(vm, addr);
1296 		if (bt == NULL) {
1297 			continue;
1298 		}
1299 		(*pr)("%p is %p+%zu in VMEM '%s' (%s)\n",
1300 		    (void *)addr, (void *)bt->bt_start,
1301 		    (size_t)(addr - bt->bt_start), vm->vm_name,
1302 		    (bt->bt_type == BT_TYPE_BUSY) ? "allocated" : "free");
1303 	}
1304 }
1305 
1306 void
1307 vmem_printall(const char *modif, void (*pr)(const char *, ...))
1308 {
1309 	const vmem_t *vm;
1310 
1311 	LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1312 		vmem_dump(vm, pr);
1313 	}
1314 }
1315 
1316 void
1317 vmem_print(uintptr_t addr, const char *modif, void (*pr)(const char *, ...))
1318 {
1319 	const vmem_t *vm = (const void *)addr;
1320 
1321 	vmem_dump(vm, pr);
1322 }
1323 #endif /* defined(DDB) */
1324 
1325 #if !defined(_KERNEL)
1326 #include <stdio.h>
1327 #endif /* !defined(_KERNEL) */
1328 
1329 #if defined(VMEM_SANITY)
1330 
1331 static bool
1332 vmem_check_sanity(vmem_t *vm)
1333 {
1334 	const bt_t *bt, *bt2;
1335 
1336 	KASSERT(vm != NULL);
1337 
1338 	CIRCLEQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1339 		if (bt->bt_start >= BT_END(bt)) {
1340 			printf("corrupted tag\n");
1341 			bt_dump(bt, (void *)printf);
1342 			return false;
1343 		}
1344 	}
1345 	CIRCLEQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1346 		CIRCLEQ_FOREACH(bt2, &vm->vm_seglist, bt_seglist) {
1347 			if (bt == bt2) {
1348 				continue;
1349 			}
1350 			if (BT_ISSPAN_P(bt) != BT_ISSPAN_P(bt2)) {
1351 				continue;
1352 			}
1353 			if (bt->bt_start < BT_END(bt2) &&
1354 			    bt2->bt_start < BT_END(bt)) {
1355 				printf("overwrapped tags\n");
1356 				bt_dump(bt, (void *)printf);
1357 				bt_dump(bt2, (void *)printf);
1358 				return false;
1359 			}
1360 		}
1361 	}
1362 
1363 	return true;
1364 }
1365 
1366 static void
1367 vmem_check(vmem_t *vm)
1368 {
1369 
1370 	if (!vmem_check_sanity(vm)) {
1371 		panic("insanity vmem %p", vm);
1372 	}
1373 }
1374 
1375 #endif /* defined(VMEM_SANITY) */
1376 
1377 #if defined(UNITTEST)
1378 int
1379 main(void)
1380 {
1381 	vmem_t *vm;
1382 	vmem_addr_t p;
1383 	struct reg {
1384 		vmem_addr_t p;
1385 		vmem_size_t sz;
1386 		bool x;
1387 	} *reg = NULL;
1388 	int nreg = 0;
1389 	int nalloc = 0;
1390 	int nfree = 0;
1391 	vmem_size_t total = 0;
1392 #if 1
1393 	vm_flag_t strat = VM_INSTANTFIT;
1394 #else
1395 	vm_flag_t strat = VM_BESTFIT;
1396 #endif
1397 
1398 	vm = vmem_create("test", VMEM_ADDR_NULL, 0, 1,
1399 	    NULL, NULL, NULL, 0, VM_SLEEP, 0/*XXX*/);
1400 	if (vm == NULL) {
1401 		printf("vmem_create\n");
1402 		exit(EXIT_FAILURE);
1403 	}
1404 	vmem_dump(vm, (void *)printf);
1405 
1406 	p = vmem_add(vm, 100, 200, VM_SLEEP);
1407 	p = vmem_add(vm, 2000, 1, VM_SLEEP);
1408 	p = vmem_add(vm, 40000, 0x10000000>>12, VM_SLEEP);
1409 	p = vmem_add(vm, 10000, 10000, VM_SLEEP);
1410 	p = vmem_add(vm, 500, 1000, VM_SLEEP);
1411 	vmem_dump(vm, (void *)printf);
1412 	for (;;) {
1413 		struct reg *r;
1414 		int t = rand() % 100;
1415 
1416 		if (t > 45) {
1417 			/* alloc */
1418 			vmem_size_t sz = rand() % 500 + 1;
1419 			bool x;
1420 			vmem_size_t align, phase, nocross;
1421 			vmem_addr_t minaddr, maxaddr;
1422 
1423 			if (t > 70) {
1424 				x = true;
1425 				/* XXX */
1426 				align = 1 << (rand() % 15);
1427 				phase = rand() % 65536;
1428 				nocross = 1 << (rand() % 15);
1429 				if (align <= phase) {
1430 					phase = 0;
1431 				}
1432 				if (VMEM_CROSS_P(phase, phase + sz - 1,
1433 				    nocross)) {
1434 					nocross = 0;
1435 				}
1436 				minaddr = rand() % 50000;
1437 				maxaddr = rand() % 70000;
1438 				if (minaddr > maxaddr) {
1439 					minaddr = 0;
1440 					maxaddr = 0;
1441 				}
1442 				printf("=== xalloc %" PRIu64
1443 				    " align=%" PRIu64 ", phase=%" PRIu64
1444 				    ", nocross=%" PRIu64 ", min=%" PRIu64
1445 				    ", max=%" PRIu64 "\n",
1446 				    (uint64_t)sz,
1447 				    (uint64_t)align,
1448 				    (uint64_t)phase,
1449 				    (uint64_t)nocross,
1450 				    (uint64_t)minaddr,
1451 				    (uint64_t)maxaddr);
1452 				p = vmem_xalloc(vm, sz, align, phase, nocross,
1453 				    minaddr, maxaddr, strat|VM_SLEEP);
1454 			} else {
1455 				x = false;
1456 				printf("=== alloc %" PRIu64 "\n", (uint64_t)sz);
1457 				p = vmem_alloc(vm, sz, strat|VM_SLEEP);
1458 			}
1459 			printf("-> %" PRIu64 "\n", (uint64_t)p);
1460 			vmem_dump(vm, (void *)printf);
1461 			if (p == VMEM_ADDR_NULL) {
1462 				if (x) {
1463 					continue;
1464 				}
1465 				break;
1466 			}
1467 			nreg++;
1468 			reg = realloc(reg, sizeof(*reg) * nreg);
1469 			r = &reg[nreg - 1];
1470 			r->p = p;
1471 			r->sz = sz;
1472 			r->x = x;
1473 			total += sz;
1474 			nalloc++;
1475 		} else if (nreg != 0) {
1476 			/* free */
1477 			r = &reg[rand() % nreg];
1478 			printf("=== free %" PRIu64 ", %" PRIu64 "\n",
1479 			    (uint64_t)r->p, (uint64_t)r->sz);
1480 			if (r->x) {
1481 				vmem_xfree(vm, r->p, r->sz);
1482 			} else {
1483 				vmem_free(vm, r->p, r->sz);
1484 			}
1485 			total -= r->sz;
1486 			vmem_dump(vm, (void *)printf);
1487 			*r = reg[nreg - 1];
1488 			nreg--;
1489 			nfree++;
1490 		}
1491 		printf("total=%" PRIu64 "\n", (uint64_t)total);
1492 	}
1493 	fprintf(stderr, "total=%" PRIu64 ", nalloc=%d, nfree=%d\n",
1494 	    (uint64_t)total, nalloc, nfree);
1495 	exit(EXIT_SUCCESS);
1496 }
1497 #endif /* defined(UNITTEST) */
1498