1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi,
5 * Copyright (c) 2013 EMC Corp.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 /*
31 * From:
32 * $NetBSD: vmem_impl.h,v 1.2 2013/01/29 21:26:24 para Exp $
33 * $NetBSD: subr_vmem.c,v 1.83 2013/03/06 11:20:10 yamt Exp $
34 */
35
36 /*
37 * reference:
38 * - Magazines and Vmem: Extending the Slab Allocator
39 * to Many CPUs and Arbitrary Resources
40 * http://www.usenix.org/event/usenix01/bonwick.html
41 */
42
43 #include <sys/cdefs.h>
44 #include "opt_ddb.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/queue.h>
50 #include <sys/callout.h>
51 #include <sys/hash.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/mutex.h>
55 #include <sys/smp.h>
56 #include <sys/condvar.h>
57 #include <sys/sysctl.h>
58 #include <sys/taskqueue.h>
59 #include <sys/vmem.h>
60 #include <sys/vmmeter.h>
61
62 #include "opt_vm.h"
63
64 #include <vm/uma.h>
65 #include <vm/vm.h>
66 #include <vm/pmap.h>
67 #include <vm/vm_map.h>
68 #include <vm/vm_object.h>
69 #include <vm/vm_kern.h>
70 #include <vm/vm_extern.h>
71 #include <vm/vm_param.h>
72 #include <vm/vm_page.h>
73 #include <vm/vm_pageout.h>
74 #include <vm/vm_phys.h>
75 #include <vm/vm_pagequeue.h>
76 #include <vm/uma_int.h>
77
78 #define VMEM_OPTORDER 5
79 #define VMEM_OPTVALUE (1 << VMEM_OPTORDER)
80 #define VMEM_MAXORDER \
81 (VMEM_OPTVALUE - 1 + sizeof(vmem_size_t) * NBBY - VMEM_OPTORDER)
82
83 #define VMEM_HASHSIZE_MIN 16
84 #define VMEM_HASHSIZE_MAX 131072
85
86 #define VMEM_QCACHE_IDX_MAX 16
87
88 #define VMEM_FITMASK (M_BESTFIT | M_FIRSTFIT | M_NEXTFIT)
89
90 #define VMEM_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM | \
91 M_BESTFIT | M_FIRSTFIT | M_NEXTFIT)
92
93 #define BT_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM)
94
95 #define QC_NAME_MAX 16
96
97 /*
98 * Data structures private to vmem.
99 */
100 MALLOC_DEFINE(M_VMEM, "vmem", "vmem internal structures");
101
102 typedef struct vmem_btag bt_t;
103
104 TAILQ_HEAD(vmem_seglist, vmem_btag);
105 LIST_HEAD(vmem_freelist, vmem_btag);
106 LIST_HEAD(vmem_hashlist, vmem_btag);
107
108 struct qcache {
109 uma_zone_t qc_cache;
110 vmem_t *qc_vmem;
111 vmem_size_t qc_size;
112 char qc_name[QC_NAME_MAX];
113 };
114 typedef struct qcache qcache_t;
115 #define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache))
116
117 #define VMEM_NAME_MAX 16
118
119 /* boundary tag */
120 struct vmem_btag {
121 TAILQ_ENTRY(vmem_btag) bt_seglist;
122 union {
123 LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */
124 LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */
125 } bt_u;
126 #define bt_hashlist bt_u.u_hashlist
127 #define bt_freelist bt_u.u_freelist
128 vmem_addr_t bt_start;
129 vmem_size_t bt_size;
130 int bt_type;
131 };
132
133 /* vmem arena */
134 struct vmem {
135 struct mtx_padalign vm_lock;
136 struct cv vm_cv;
137 char vm_name[VMEM_NAME_MAX+1];
138 LIST_ENTRY(vmem) vm_alllist;
139 struct vmem_hashlist vm_hash0[VMEM_HASHSIZE_MIN];
140 struct vmem_freelist vm_freelist[VMEM_MAXORDER];
141 struct vmem_seglist vm_seglist;
142 struct vmem_hashlist *vm_hashlist;
143 vmem_size_t vm_hashsize;
144
145 /* Constant after init */
146 vmem_size_t vm_qcache_max;
147 vmem_size_t vm_quantum_mask;
148 vmem_size_t vm_import_quantum;
149 int vm_quantum_shift;
150
151 /* Written on alloc/free */
152 LIST_HEAD(, vmem_btag) vm_freetags;
153 int vm_nfreetags;
154 int vm_nbusytag;
155 vmem_size_t vm_inuse;
156 vmem_size_t vm_size;
157 vmem_size_t vm_limit;
158 struct vmem_btag vm_cursor;
159
160 /* Used on import. */
161 vmem_import_t *vm_importfn;
162 vmem_release_t *vm_releasefn;
163 void *vm_arg;
164
165 /* Space exhaustion callback. */
166 vmem_reclaim_t *vm_reclaimfn;
167
168 /* quantum cache */
169 qcache_t vm_qcache[VMEM_QCACHE_IDX_MAX];
170 };
171
172 #define BT_TYPE_SPAN 1 /* Allocated from importfn */
173 #define BT_TYPE_SPAN_STATIC 2 /* vmem_add() or create. */
174 #define BT_TYPE_FREE 3 /* Available space. */
175 #define BT_TYPE_BUSY 4 /* Used space. */
176 #define BT_TYPE_CURSOR 5 /* Cursor for nextfit allocations. */
177 #define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC)
178
179 #define BT_END(bt) ((bt)->bt_start + (bt)->bt_size - 1)
180
181 #if defined(DIAGNOSTIC)
182 static int enable_vmem_check = 0;
183 SYSCTL_INT(_debug, OID_AUTO, vmem_check, CTLFLAG_RWTUN,
184 &enable_vmem_check, 0, "Enable vmem check");
185 static void vmem_check(vmem_t *);
186 #endif
187
188 static struct callout vmem_periodic_ch;
189 static int vmem_periodic_interval;
190 static struct task vmem_periodic_wk;
191
192 static struct mtx_padalign __exclusive_cache_line vmem_list_lock;
193 static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list);
194 static uma_zone_t vmem_zone;
195
196 /* ---- misc */
197 #define VMEM_CONDVAR_INIT(vm, wchan) cv_init(&vm->vm_cv, wchan)
198 #define VMEM_CONDVAR_DESTROY(vm) cv_destroy(&vm->vm_cv)
199 #define VMEM_CONDVAR_WAIT(vm) cv_wait(&vm->vm_cv, &vm->vm_lock)
200 #define VMEM_CONDVAR_BROADCAST(vm) cv_broadcast(&vm->vm_cv)
201
202 #define VMEM_LOCK(vm) mtx_lock(&vm->vm_lock)
203 #define VMEM_TRYLOCK(vm) mtx_trylock(&vm->vm_lock)
204 #define VMEM_UNLOCK(vm) mtx_unlock(&vm->vm_lock)
205 #define VMEM_LOCK_INIT(vm, name) mtx_init(&vm->vm_lock, (name), NULL, MTX_DEF)
206 #define VMEM_LOCK_DESTROY(vm) mtx_destroy(&vm->vm_lock)
207 #define VMEM_ASSERT_LOCKED(vm) mtx_assert(&vm->vm_lock, MA_OWNED);
208
209 #define VMEM_ALIGNUP(addr, align) (-(-(addr) & -(align)))
210
211 #define VMEM_CROSS_P(addr1, addr2, boundary) \
212 ((((addr1) ^ (addr2)) & -(boundary)) != 0)
213
214 #define ORDER2SIZE(order) ((order) < VMEM_OPTVALUE ? ((order) + 1) : \
215 (vmem_size_t)1 << ((order) - (VMEM_OPTVALUE - VMEM_OPTORDER - 1)))
216 #define SIZE2ORDER(size) ((size) <= VMEM_OPTVALUE ? ((size) - 1) : \
217 (flsl(size) + (VMEM_OPTVALUE - VMEM_OPTORDER - 2)))
218
219 /*
220 * Maximum number of boundary tags that may be required to satisfy an
221 * allocation. Two may be required to import. Another two may be
222 * required to clip edges.
223 */
224 #define BT_MAXALLOC 4
225
226 /*
227 * Max free limits the number of locally cached boundary tags. We
228 * just want to avoid hitting the zone allocator for every call.
229 */
230 #define BT_MAXFREE (BT_MAXALLOC * 8)
231
232 /* Allocator for boundary tags. */
233 static uma_zone_t vmem_bt_zone;
234
235 /* boot time arena storage. */
236 static struct vmem kernel_arena_storage;
237 static struct vmem buffer_arena_storage;
238 static struct vmem transient_arena_storage;
239 /* kernel and kmem arenas are aliased for backwards KPI compat. */
240 vmem_t *kernel_arena = &kernel_arena_storage;
241 vmem_t *kmem_arena = &kernel_arena_storage;
242 vmem_t *buffer_arena = &buffer_arena_storage;
243 vmem_t *transient_arena = &transient_arena_storage;
244
245 #ifdef DEBUG_MEMGUARD
246 static struct vmem memguard_arena_storage;
247 vmem_t *memguard_arena = &memguard_arena_storage;
248 #endif
249
250 static bool
bt_isbusy(bt_t * bt)251 bt_isbusy(bt_t *bt)
252 {
253 return (bt->bt_type == BT_TYPE_BUSY);
254 }
255
256 static bool
bt_isfree(bt_t * bt)257 bt_isfree(bt_t *bt)
258 {
259 return (bt->bt_type == BT_TYPE_FREE);
260 }
261
262 /*
263 * Fill the vmem's boundary tag cache. We guarantee that boundary tag
264 * allocation will not fail once bt_fill() passes. To do so we cache
265 * at least the maximum possible tag allocations in the arena.
266 */
267 static __noinline int
_bt_fill(vmem_t * vm,int flags)268 _bt_fill(vmem_t *vm, int flags)
269 {
270 bt_t *bt;
271
272 VMEM_ASSERT_LOCKED(vm);
273
274 /*
275 * Only allow the kernel arena and arenas derived from kernel arena to
276 * dip into reserve tags. They are where new tags come from.
277 */
278 flags &= BT_FLAGS;
279 if (vm != kernel_arena && vm->vm_arg != kernel_arena)
280 flags &= ~M_USE_RESERVE;
281
282 /*
283 * Loop until we meet the reserve. To minimize the lock shuffle
284 * and prevent simultaneous fills we first try a NOWAIT regardless
285 * of the caller's flags. Specify M_NOVM so we don't recurse while
286 * holding a vmem lock.
287 */
288 while (vm->vm_nfreetags < BT_MAXALLOC) {
289 bt = uma_zalloc(vmem_bt_zone,
290 (flags & M_USE_RESERVE) | M_NOWAIT | M_NOVM);
291 if (bt == NULL) {
292 VMEM_UNLOCK(vm);
293 bt = uma_zalloc(vmem_bt_zone, flags);
294 VMEM_LOCK(vm);
295 if (bt == NULL)
296 break;
297 }
298 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
299 vm->vm_nfreetags++;
300 }
301
302 if (vm->vm_nfreetags < BT_MAXALLOC)
303 return ENOMEM;
304
305 return 0;
306 }
307
308 static inline int
bt_fill(vmem_t * vm,int flags)309 bt_fill(vmem_t *vm, int flags)
310 {
311 if (vm->vm_nfreetags >= BT_MAXALLOC)
312 return (0);
313 return (_bt_fill(vm, flags));
314 }
315
316 /*
317 * Pop a tag off of the freetag stack.
318 */
319 static bt_t *
bt_alloc(vmem_t * vm)320 bt_alloc(vmem_t *vm)
321 {
322 bt_t *bt;
323
324 VMEM_ASSERT_LOCKED(vm);
325 bt = LIST_FIRST(&vm->vm_freetags);
326 MPASS(bt != NULL);
327 LIST_REMOVE(bt, bt_freelist);
328 vm->vm_nfreetags--;
329
330 return bt;
331 }
332
333 /*
334 * Trim the per-vmem free list. Returns with the lock released to
335 * avoid allocator recursions.
336 */
337 static void
bt_freetrim(vmem_t * vm,int freelimit)338 bt_freetrim(vmem_t *vm, int freelimit)
339 {
340 LIST_HEAD(, vmem_btag) freetags;
341 bt_t *bt;
342
343 LIST_INIT(&freetags);
344 VMEM_ASSERT_LOCKED(vm);
345 while (vm->vm_nfreetags > freelimit) {
346 bt = LIST_FIRST(&vm->vm_freetags);
347 LIST_REMOVE(bt, bt_freelist);
348 vm->vm_nfreetags--;
349 LIST_INSERT_HEAD(&freetags, bt, bt_freelist);
350 }
351 VMEM_UNLOCK(vm);
352 while ((bt = LIST_FIRST(&freetags)) != NULL) {
353 LIST_REMOVE(bt, bt_freelist);
354 uma_zfree(vmem_bt_zone, bt);
355 }
356 }
357
358 static inline void
bt_free(vmem_t * vm,bt_t * bt)359 bt_free(vmem_t *vm, bt_t *bt)
360 {
361
362 VMEM_ASSERT_LOCKED(vm);
363 MPASS(LIST_FIRST(&vm->vm_freetags) != bt);
364 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
365 vm->vm_nfreetags++;
366 }
367
368 /*
369 * Hide MAXALLOC tags before dropping the arena lock to ensure that a
370 * concurrent allocation attempt does not grab them.
371 */
372 static void
bt_save(vmem_t * vm)373 bt_save(vmem_t *vm)
374 {
375 KASSERT(vm->vm_nfreetags >= BT_MAXALLOC,
376 ("%s: insufficient free tags %d", __func__, vm->vm_nfreetags));
377 vm->vm_nfreetags -= BT_MAXALLOC;
378 }
379
380 static void
bt_restore(vmem_t * vm)381 bt_restore(vmem_t *vm)
382 {
383 vm->vm_nfreetags += BT_MAXALLOC;
384 }
385
386 /*
387 * freelist[0] ... [1, 1]
388 * freelist[1] ... [2, 2]
389 * :
390 * freelist[29] ... [30, 30]
391 * freelist[30] ... [31, 31]
392 * freelist[31] ... [32, 63]
393 * freelist[33] ... [64, 127]
394 * :
395 * freelist[n] ... [(1 << (n - 26)), (1 << (n - 25)) - 1]
396 * :
397 */
398
399 static struct vmem_freelist *
bt_freehead_tofree(vmem_t * vm,vmem_size_t size)400 bt_freehead_tofree(vmem_t *vm, vmem_size_t size)
401 {
402 const vmem_size_t qsize = size >> vm->vm_quantum_shift;
403 const int idx = SIZE2ORDER(qsize);
404
405 MPASS(size != 0 && qsize != 0);
406 MPASS((size & vm->vm_quantum_mask) == 0);
407 MPASS(idx >= 0);
408 MPASS(idx < VMEM_MAXORDER);
409
410 return &vm->vm_freelist[idx];
411 }
412
413 /*
414 * bt_freehead_toalloc: return the freelist for the given size and allocation
415 * strategy.
416 *
417 * For M_FIRSTFIT, return the list in which any blocks are large enough
418 * for the requested size. otherwise, return the list which can have blocks
419 * large enough for the requested size.
420 */
421 static struct vmem_freelist *
bt_freehead_toalloc(vmem_t * vm,vmem_size_t size,int strat)422 bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, int strat)
423 {
424 const vmem_size_t qsize = size >> vm->vm_quantum_shift;
425 int idx = SIZE2ORDER(qsize);
426
427 MPASS(size != 0 && qsize != 0);
428 MPASS((size & vm->vm_quantum_mask) == 0);
429
430 if (strat == M_FIRSTFIT && ORDER2SIZE(idx) != qsize) {
431 idx++;
432 /* check too large request? */
433 }
434 MPASS(idx >= 0);
435 MPASS(idx < VMEM_MAXORDER);
436
437 return &vm->vm_freelist[idx];
438 }
439
440 /* ---- boundary tag hash */
441
442 static struct vmem_hashlist *
bt_hashhead(vmem_t * vm,vmem_addr_t addr)443 bt_hashhead(vmem_t *vm, vmem_addr_t addr)
444 {
445 struct vmem_hashlist *list;
446 unsigned int hash;
447
448 hash = hash32_buf(&addr, sizeof(addr), 0);
449 list = &vm->vm_hashlist[hash % vm->vm_hashsize];
450
451 return list;
452 }
453
454 static bt_t *
bt_lookupbusy(vmem_t * vm,vmem_addr_t addr)455 bt_lookupbusy(vmem_t *vm, vmem_addr_t addr)
456 {
457 struct vmem_hashlist *list;
458 bt_t *bt;
459
460 VMEM_ASSERT_LOCKED(vm);
461 list = bt_hashhead(vm, addr);
462 LIST_FOREACH(bt, list, bt_hashlist) {
463 if (bt->bt_start == addr) {
464 break;
465 }
466 }
467
468 return bt;
469 }
470
471 static void
bt_rembusy(vmem_t * vm,bt_t * bt)472 bt_rembusy(vmem_t *vm, bt_t *bt)
473 {
474
475 VMEM_ASSERT_LOCKED(vm);
476 MPASS(vm->vm_nbusytag > 0);
477 vm->vm_inuse -= bt->bt_size;
478 vm->vm_nbusytag--;
479 LIST_REMOVE(bt, bt_hashlist);
480 }
481
482 static void
bt_insbusy(vmem_t * vm,bt_t * bt)483 bt_insbusy(vmem_t *vm, bt_t *bt)
484 {
485 struct vmem_hashlist *list;
486
487 VMEM_ASSERT_LOCKED(vm);
488 MPASS(bt->bt_type == BT_TYPE_BUSY);
489
490 list = bt_hashhead(vm, bt->bt_start);
491 LIST_INSERT_HEAD(list, bt, bt_hashlist);
492 vm->vm_nbusytag++;
493 vm->vm_inuse += bt->bt_size;
494 }
495
496 /* ---- boundary tag list */
497
498 static void
bt_remseg(vmem_t * vm,bt_t * bt)499 bt_remseg(vmem_t *vm, bt_t *bt)
500 {
501
502 MPASS(bt->bt_type != BT_TYPE_CURSOR);
503 TAILQ_REMOVE(&vm->vm_seglist, bt, bt_seglist);
504 bt_free(vm, bt);
505 }
506
507 static void
bt_insseg(vmem_t * vm,bt_t * bt,bt_t * prev)508 bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev)
509 {
510
511 TAILQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist);
512 }
513
514 static void
bt_insseg_tail(vmem_t * vm,bt_t * bt)515 bt_insseg_tail(vmem_t *vm, bt_t *bt)
516 {
517
518 TAILQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist);
519 }
520
521 static void
bt_remfree(vmem_t * vm __unused,bt_t * bt)522 bt_remfree(vmem_t *vm __unused, bt_t *bt)
523 {
524
525 MPASS(bt->bt_type == BT_TYPE_FREE);
526
527 LIST_REMOVE(bt, bt_freelist);
528 }
529
530 static void
bt_insfree(vmem_t * vm,bt_t * bt)531 bt_insfree(vmem_t *vm, bt_t *bt)
532 {
533 struct vmem_freelist *list;
534
535 list = bt_freehead_tofree(vm, bt->bt_size);
536 LIST_INSERT_HEAD(list, bt, bt_freelist);
537 }
538
539 /* ---- vmem internal functions */
540
541 /*
542 * Import from the arena into the quantum cache in UMA.
543 *
544 * We use VMEM_ADDR_QCACHE_MIN instead of 0: uma_zalloc() returns 0 to indicate
545 * failure, so UMA can't be used to cache a resource with value 0.
546 */
547 static int
qc_import(void * arg,void ** store,int cnt,int domain,int flags)548 qc_import(void *arg, void **store, int cnt, int domain, int flags)
549 {
550 qcache_t *qc;
551 vmem_addr_t addr;
552 int i;
553
554 KASSERT((flags & M_WAITOK) == 0, ("blocking allocation"));
555
556 qc = arg;
557 for (i = 0; i < cnt; i++) {
558 if (vmem_xalloc(qc->qc_vmem, qc->qc_size, 0, 0, 0,
559 VMEM_ADDR_QCACHE_MIN, VMEM_ADDR_MAX, flags, &addr) != 0)
560 break;
561 store[i] = (void *)addr;
562 }
563 return (i);
564 }
565
566 /*
567 * Release memory from the UMA cache to the arena.
568 */
569 static void
qc_release(void * arg,void ** store,int cnt)570 qc_release(void *arg, void **store, int cnt)
571 {
572 qcache_t *qc;
573 int i;
574
575 qc = arg;
576 for (i = 0; i < cnt; i++)
577 vmem_xfree(qc->qc_vmem, (vmem_addr_t)store[i], qc->qc_size);
578 }
579
580 static void
qc_init(vmem_t * vm,vmem_size_t qcache_max)581 qc_init(vmem_t *vm, vmem_size_t qcache_max)
582 {
583 qcache_t *qc;
584 vmem_size_t size;
585 int qcache_idx_max;
586 int i;
587
588 MPASS((qcache_max & vm->vm_quantum_mask) == 0);
589 qcache_idx_max = MIN(qcache_max >> vm->vm_quantum_shift,
590 VMEM_QCACHE_IDX_MAX);
591 vm->vm_qcache_max = qcache_idx_max << vm->vm_quantum_shift;
592 for (i = 0; i < qcache_idx_max; i++) {
593 qc = &vm->vm_qcache[i];
594 size = (i + 1) << vm->vm_quantum_shift;
595 snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu",
596 vm->vm_name, size);
597 qc->qc_vmem = vm;
598 qc->qc_size = size;
599 qc->qc_cache = uma_zcache_create(qc->qc_name, size,
600 NULL, NULL, NULL, NULL, qc_import, qc_release, qc, 0);
601 MPASS(qc->qc_cache);
602 }
603 }
604
605 static void
qc_destroy(vmem_t * vm)606 qc_destroy(vmem_t *vm)
607 {
608 int qcache_idx_max;
609 int i;
610
611 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
612 for (i = 0; i < qcache_idx_max; i++)
613 uma_zdestroy(vm->vm_qcache[i].qc_cache);
614 }
615
616 static void
qc_drain(vmem_t * vm)617 qc_drain(vmem_t *vm)
618 {
619 int qcache_idx_max;
620 int i;
621
622 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
623 for (i = 0; i < qcache_idx_max; i++)
624 uma_zone_reclaim(vm->vm_qcache[i].qc_cache, UMA_RECLAIM_DRAIN);
625 }
626
627 #ifndef UMA_MD_SMALL_ALLOC
628
629 static struct mtx_padalign __exclusive_cache_line vmem_bt_lock;
630
631 /*
632 * vmem_bt_alloc: Allocate a new page of boundary tags.
633 *
634 * On architectures with uma_small_alloc there is no recursion; no address
635 * space need be allocated to allocate boundary tags. For the others, we
636 * must handle recursion. Boundary tags are necessary to allocate new
637 * boundary tags.
638 *
639 * UMA guarantees that enough tags are held in reserve to allocate a new
640 * page of kva. We dip into this reserve by specifying M_USE_RESERVE only
641 * when allocating the page to hold new boundary tags. In this way the
642 * reserve is automatically filled by the allocation that uses the reserve.
643 *
644 * We still have to guarantee that the new tags are allocated atomically since
645 * many threads may try concurrently. The bt_lock provides this guarantee.
646 * We convert WAITOK allocations to NOWAIT and then handle the blocking here
647 * on failure. It's ok to return NULL for a WAITOK allocation as UMA will
648 * loop again after checking to see if we lost the race to allocate.
649 *
650 * There is a small race between vmem_bt_alloc() returning the page and the
651 * zone lock being acquired to add the page to the zone. For WAITOK
652 * allocations we just pause briefly. NOWAIT may experience a transient
653 * failure. To alleviate this we permit a small number of simultaneous
654 * fills to proceed concurrently so NOWAIT is less likely to fail unless
655 * we are really out of KVA.
656 */
657 static void *
vmem_bt_alloc(uma_zone_t zone,vm_size_t bytes,int domain,uint8_t * pflag,int wait)658 vmem_bt_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
659 int wait)
660 {
661 vmem_addr_t addr;
662
663 *pflag = UMA_SLAB_KERNEL;
664
665 /*
666 * Single thread boundary tag allocation so that the address space
667 * and memory are added in one atomic operation.
668 */
669 mtx_lock(&vmem_bt_lock);
670 if (vmem_xalloc(vm_dom[domain].vmd_kernel_arena, bytes, 0, 0, 0,
671 VMEM_ADDR_MIN, VMEM_ADDR_MAX,
672 M_NOWAIT | M_NOVM | M_USE_RESERVE | M_BESTFIT, &addr) == 0) {
673 if (kmem_back_domain(domain, kernel_object, addr, bytes,
674 M_NOWAIT | M_USE_RESERVE) == 0) {
675 mtx_unlock(&vmem_bt_lock);
676 return ((void *)addr);
677 }
678 vmem_xfree(vm_dom[domain].vmd_kernel_arena, addr, bytes);
679 mtx_unlock(&vmem_bt_lock);
680 /*
681 * Out of memory, not address space. This may not even be
682 * possible due to M_USE_RESERVE page allocation.
683 */
684 if (wait & M_WAITOK)
685 vm_wait_domain(domain);
686 return (NULL);
687 }
688 mtx_unlock(&vmem_bt_lock);
689 /*
690 * We're either out of address space or lost a fill race.
691 */
692 if (wait & M_WAITOK)
693 pause("btalloc", 1);
694
695 return (NULL);
696 }
697 #endif
698
699 void
vmem_startup(void)700 vmem_startup(void)
701 {
702
703 mtx_init(&vmem_list_lock, "vmem list lock", NULL, MTX_DEF);
704 vmem_zone = uma_zcreate("vmem",
705 sizeof(struct vmem), NULL, NULL, NULL, NULL,
706 UMA_ALIGN_PTR, 0);
707 vmem_bt_zone = uma_zcreate("vmem btag",
708 sizeof(struct vmem_btag), NULL, NULL, NULL, NULL,
709 UMA_ALIGN_PTR, UMA_ZONE_VM);
710 #ifndef UMA_MD_SMALL_ALLOC
711 mtx_init(&vmem_bt_lock, "btag lock", NULL, MTX_DEF);
712 uma_prealloc(vmem_bt_zone, BT_MAXALLOC);
713 /*
714 * Reserve enough tags to allocate new tags. We allow multiple
715 * CPUs to attempt to allocate new tags concurrently to limit
716 * false restarts in UMA. vmem_bt_alloc() allocates from a per-domain
717 * arena, which may involve importing a range from the kernel arena,
718 * so we need to keep at least 2 * BT_MAXALLOC tags reserved.
719 */
720 uma_zone_reserve(vmem_bt_zone, 2 * BT_MAXALLOC * mp_ncpus);
721 uma_zone_set_allocf(vmem_bt_zone, vmem_bt_alloc);
722 #endif
723 }
724
725 /* ---- rehash */
726
727 static int
vmem_rehash(vmem_t * vm,vmem_size_t newhashsize)728 vmem_rehash(vmem_t *vm, vmem_size_t newhashsize)
729 {
730 bt_t *bt;
731 struct vmem_hashlist *newhashlist;
732 struct vmem_hashlist *oldhashlist;
733 vmem_size_t i, oldhashsize;
734
735 MPASS(newhashsize > 0);
736
737 newhashlist = malloc(sizeof(struct vmem_hashlist) * newhashsize,
738 M_VMEM, M_NOWAIT);
739 if (newhashlist == NULL)
740 return ENOMEM;
741 for (i = 0; i < newhashsize; i++) {
742 LIST_INIT(&newhashlist[i]);
743 }
744
745 VMEM_LOCK(vm);
746 oldhashlist = vm->vm_hashlist;
747 oldhashsize = vm->vm_hashsize;
748 vm->vm_hashlist = newhashlist;
749 vm->vm_hashsize = newhashsize;
750 if (oldhashlist == NULL) {
751 VMEM_UNLOCK(vm);
752 return 0;
753 }
754 for (i = 0; i < oldhashsize; i++) {
755 while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) {
756 bt_rembusy(vm, bt);
757 bt_insbusy(vm, bt);
758 }
759 }
760 VMEM_UNLOCK(vm);
761
762 if (oldhashlist != vm->vm_hash0)
763 free(oldhashlist, M_VMEM);
764
765 return 0;
766 }
767
768 static void
vmem_periodic_kick(void * dummy)769 vmem_periodic_kick(void *dummy)
770 {
771
772 taskqueue_enqueue(taskqueue_thread, &vmem_periodic_wk);
773 }
774
775 static void
vmem_periodic(void * unused,int pending)776 vmem_periodic(void *unused, int pending)
777 {
778 vmem_t *vm;
779 vmem_size_t desired;
780 vmem_size_t current;
781
782 mtx_lock(&vmem_list_lock);
783 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
784 #ifdef DIAGNOSTIC
785 /* Convenient time to verify vmem state. */
786 if (enable_vmem_check == 1) {
787 VMEM_LOCK(vm);
788 vmem_check(vm);
789 VMEM_UNLOCK(vm);
790 }
791 #endif
792 desired = 1 << flsl(vm->vm_nbusytag);
793 desired = MIN(MAX(desired, VMEM_HASHSIZE_MIN),
794 VMEM_HASHSIZE_MAX);
795 current = vm->vm_hashsize;
796
797 /* Grow in powers of two. Shrink less aggressively. */
798 if (desired >= current * 2 || desired * 4 <= current)
799 vmem_rehash(vm, desired);
800
801 /*
802 * Periodically wake up threads waiting for resources,
803 * so they could ask for reclamation again.
804 */
805 VMEM_CONDVAR_BROADCAST(vm);
806 }
807 mtx_unlock(&vmem_list_lock);
808
809 callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
810 vmem_periodic_kick, NULL);
811 }
812
813 static void
vmem_start_callout(void * unused)814 vmem_start_callout(void *unused)
815 {
816
817 TASK_INIT(&vmem_periodic_wk, 0, vmem_periodic, NULL);
818 vmem_periodic_interval = hz * 10;
819 callout_init(&vmem_periodic_ch, 1);
820 callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
821 vmem_periodic_kick, NULL);
822 }
823 SYSINIT(vfs, SI_SUB_CONFIGURE, SI_ORDER_ANY, vmem_start_callout, NULL);
824
825 static void
vmem_add1(vmem_t * vm,vmem_addr_t addr,vmem_size_t size,int type)826 vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int type)
827 {
828 bt_t *btfree, *btprev, *btspan;
829
830 VMEM_ASSERT_LOCKED(vm);
831 MPASS(type == BT_TYPE_SPAN || type == BT_TYPE_SPAN_STATIC);
832 MPASS((size & vm->vm_quantum_mask) == 0);
833
834 if (vm->vm_releasefn == NULL) {
835 /*
836 * The new segment will never be released, so see if it is
837 * contiguous with respect to an existing segment. In this case
838 * a span tag is not needed, and it may be possible now or in
839 * the future to coalesce the new segment with an existing free
840 * segment.
841 */
842 btprev = TAILQ_LAST(&vm->vm_seglist, vmem_seglist);
843 if ((!bt_isbusy(btprev) && !bt_isfree(btprev)) ||
844 btprev->bt_start + btprev->bt_size != addr)
845 btprev = NULL;
846 } else {
847 btprev = NULL;
848 }
849
850 if (btprev == NULL || bt_isbusy(btprev)) {
851 if (btprev == NULL) {
852 btspan = bt_alloc(vm);
853 btspan->bt_type = type;
854 btspan->bt_start = addr;
855 btspan->bt_size = size;
856 bt_insseg_tail(vm, btspan);
857 }
858
859 btfree = bt_alloc(vm);
860 btfree->bt_type = BT_TYPE_FREE;
861 btfree->bt_start = addr;
862 btfree->bt_size = size;
863 bt_insseg_tail(vm, btfree);
864 bt_insfree(vm, btfree);
865 } else {
866 bt_remfree(vm, btprev);
867 btprev->bt_size += size;
868 bt_insfree(vm, btprev);
869 }
870
871 vm->vm_size += size;
872 }
873
874 static void
vmem_destroy1(vmem_t * vm)875 vmem_destroy1(vmem_t *vm)
876 {
877 bt_t *bt;
878
879 /*
880 * Drain per-cpu quantum caches.
881 */
882 qc_destroy(vm);
883
884 /*
885 * The vmem should now only contain empty segments.
886 */
887 VMEM_LOCK(vm);
888 MPASS(vm->vm_nbusytag == 0);
889
890 TAILQ_REMOVE(&vm->vm_seglist, &vm->vm_cursor, bt_seglist);
891 while ((bt = TAILQ_FIRST(&vm->vm_seglist)) != NULL)
892 bt_remseg(vm, bt);
893
894 if (vm->vm_hashlist != NULL && vm->vm_hashlist != vm->vm_hash0)
895 free(vm->vm_hashlist, M_VMEM);
896
897 bt_freetrim(vm, 0);
898
899 VMEM_CONDVAR_DESTROY(vm);
900 VMEM_LOCK_DESTROY(vm);
901 uma_zfree(vmem_zone, vm);
902 }
903
904 static int
vmem_import(vmem_t * vm,vmem_size_t size,vmem_size_t align,int flags)905 vmem_import(vmem_t *vm, vmem_size_t size, vmem_size_t align, int flags)
906 {
907 vmem_addr_t addr;
908 int error;
909
910 if (vm->vm_importfn == NULL)
911 return (EINVAL);
912
913 /*
914 * To make sure we get a span that meets the alignment we double it
915 * and add the size to the tail. This slightly overestimates.
916 */
917 if (align != vm->vm_quantum_mask + 1)
918 size = (align * 2) + size;
919 size = roundup(size, vm->vm_import_quantum);
920
921 if (vm->vm_limit != 0 && vm->vm_limit < vm->vm_size + size)
922 return (ENOMEM);
923
924 bt_save(vm);
925 VMEM_UNLOCK(vm);
926 error = (vm->vm_importfn)(vm->vm_arg, size, flags, &addr);
927 VMEM_LOCK(vm);
928 bt_restore(vm);
929 if (error)
930 return (ENOMEM);
931
932 vmem_add1(vm, addr, size, BT_TYPE_SPAN);
933
934 return 0;
935 }
936
937 /*
938 * vmem_fit: check if a bt can satisfy the given restrictions.
939 *
940 * it's a caller's responsibility to ensure the region is big enough
941 * before calling us.
942 */
943 static int
vmem_fit(const bt_t * bt,vmem_size_t size,vmem_size_t align,vmem_size_t phase,vmem_size_t nocross,vmem_addr_t minaddr,vmem_addr_t maxaddr,vmem_addr_t * addrp)944 vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align,
945 vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr,
946 vmem_addr_t maxaddr, vmem_addr_t *addrp)
947 {
948 vmem_addr_t start;
949 vmem_addr_t end;
950
951 MPASS(size > 0);
952 MPASS(bt->bt_size >= size); /* caller's responsibility */
953
954 /*
955 * XXX assumption: vmem_addr_t and vmem_size_t are
956 * unsigned integer of the same size.
957 */
958
959 start = bt->bt_start;
960 if (start < minaddr) {
961 start = minaddr;
962 }
963 end = BT_END(bt);
964 if (end > maxaddr)
965 end = maxaddr;
966 if (start > end)
967 return (ENOMEM);
968
969 start = VMEM_ALIGNUP(start - phase, align) + phase;
970 if (start < bt->bt_start)
971 start += align;
972 if (VMEM_CROSS_P(start, start + size - 1, nocross)) {
973 MPASS(align < nocross);
974 start = VMEM_ALIGNUP(start - phase, nocross) + phase;
975 }
976 if (start <= end && end - start >= size - 1) {
977 MPASS((start & (align - 1)) == phase);
978 MPASS(!VMEM_CROSS_P(start, start + size - 1, nocross));
979 MPASS(minaddr <= start);
980 MPASS(maxaddr == 0 || start + size - 1 <= maxaddr);
981 MPASS(bt->bt_start <= start);
982 MPASS(BT_END(bt) - start >= size - 1);
983 *addrp = start;
984
985 return (0);
986 }
987 return (ENOMEM);
988 }
989
990 /*
991 * vmem_clip: Trim the boundary tag edges to the requested start and size.
992 */
993 static void
vmem_clip(vmem_t * vm,bt_t * bt,vmem_addr_t start,vmem_size_t size)994 vmem_clip(vmem_t *vm, bt_t *bt, vmem_addr_t start, vmem_size_t size)
995 {
996 bt_t *btnew;
997 bt_t *btprev;
998
999 VMEM_ASSERT_LOCKED(vm);
1000 MPASS(bt->bt_type == BT_TYPE_FREE);
1001 MPASS(bt->bt_size >= size);
1002 bt_remfree(vm, bt);
1003 if (bt->bt_start != start) {
1004 btprev = bt_alloc(vm);
1005 btprev->bt_type = BT_TYPE_FREE;
1006 btprev->bt_start = bt->bt_start;
1007 btprev->bt_size = start - bt->bt_start;
1008 bt->bt_start = start;
1009 bt->bt_size -= btprev->bt_size;
1010 bt_insfree(vm, btprev);
1011 bt_insseg(vm, btprev,
1012 TAILQ_PREV(bt, vmem_seglist, bt_seglist));
1013 }
1014 MPASS(bt->bt_start == start);
1015 if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) {
1016 /* split */
1017 btnew = bt_alloc(vm);
1018 btnew->bt_type = BT_TYPE_BUSY;
1019 btnew->bt_start = bt->bt_start;
1020 btnew->bt_size = size;
1021 bt->bt_start = bt->bt_start + size;
1022 bt->bt_size -= size;
1023 bt_insfree(vm, bt);
1024 bt_insseg(vm, btnew,
1025 TAILQ_PREV(bt, vmem_seglist, bt_seglist));
1026 bt_insbusy(vm, btnew);
1027 bt = btnew;
1028 } else {
1029 bt->bt_type = BT_TYPE_BUSY;
1030 bt_insbusy(vm, bt);
1031 }
1032 MPASS(bt->bt_size >= size);
1033 }
1034
1035 static int
vmem_try_fetch(vmem_t * vm,const vmem_size_t size,vmem_size_t align,int flags)1036 vmem_try_fetch(vmem_t *vm, const vmem_size_t size, vmem_size_t align, int flags)
1037 {
1038 vmem_size_t avail;
1039
1040 VMEM_ASSERT_LOCKED(vm);
1041
1042 /*
1043 * XXX it is possible to fail to meet xalloc constraints with the
1044 * imported region. It is up to the user to specify the
1045 * import quantum such that it can satisfy any allocation.
1046 */
1047 if (vmem_import(vm, size, align, flags) == 0)
1048 return (1);
1049
1050 /*
1051 * Try to free some space from the quantum cache or reclaim
1052 * functions if available.
1053 */
1054 if (vm->vm_qcache_max != 0 || vm->vm_reclaimfn != NULL) {
1055 avail = vm->vm_size - vm->vm_inuse;
1056 bt_save(vm);
1057 VMEM_UNLOCK(vm);
1058 if (vm->vm_qcache_max != 0)
1059 qc_drain(vm);
1060 if (vm->vm_reclaimfn != NULL)
1061 vm->vm_reclaimfn(vm, flags);
1062 VMEM_LOCK(vm);
1063 bt_restore(vm);
1064 /* If we were successful retry even NOWAIT. */
1065 if (vm->vm_size - vm->vm_inuse > avail)
1066 return (1);
1067 }
1068 if ((flags & M_NOWAIT) != 0)
1069 return (0);
1070 bt_save(vm);
1071 VMEM_CONDVAR_WAIT(vm);
1072 bt_restore(vm);
1073 return (1);
1074 }
1075
1076 static int
vmem_try_release(vmem_t * vm,struct vmem_btag * bt,const bool remfree)1077 vmem_try_release(vmem_t *vm, struct vmem_btag *bt, const bool remfree)
1078 {
1079 struct vmem_btag *prev;
1080
1081 MPASS(bt->bt_type == BT_TYPE_FREE);
1082
1083 if (vm->vm_releasefn == NULL)
1084 return (0);
1085
1086 prev = TAILQ_PREV(bt, vmem_seglist, bt_seglist);
1087 MPASS(prev != NULL);
1088 MPASS(prev->bt_type != BT_TYPE_FREE);
1089
1090 if (prev->bt_type == BT_TYPE_SPAN && prev->bt_size == bt->bt_size) {
1091 vmem_addr_t spanaddr;
1092 vmem_size_t spansize;
1093
1094 MPASS(prev->bt_start == bt->bt_start);
1095 spanaddr = prev->bt_start;
1096 spansize = prev->bt_size;
1097 if (remfree)
1098 bt_remfree(vm, bt);
1099 bt_remseg(vm, bt);
1100 bt_remseg(vm, prev);
1101 vm->vm_size -= spansize;
1102 VMEM_CONDVAR_BROADCAST(vm);
1103 bt_freetrim(vm, BT_MAXFREE);
1104 vm->vm_releasefn(vm->vm_arg, spanaddr, spansize);
1105 return (1);
1106 }
1107 return (0);
1108 }
1109
1110 static int
vmem_xalloc_nextfit(vmem_t * vm,const vmem_size_t size,vmem_size_t align,const vmem_size_t phase,const vmem_size_t nocross,int flags,vmem_addr_t * addrp)1111 vmem_xalloc_nextfit(vmem_t *vm, const vmem_size_t size, vmem_size_t align,
1112 const vmem_size_t phase, const vmem_size_t nocross, int flags,
1113 vmem_addr_t *addrp)
1114 {
1115 struct vmem_btag *bt, *cursor, *next, *prev;
1116 int error;
1117
1118 error = ENOMEM;
1119 VMEM_LOCK(vm);
1120
1121 /*
1122 * Make sure we have enough tags to complete the operation.
1123 */
1124 if (bt_fill(vm, flags) != 0)
1125 goto out;
1126
1127 retry:
1128 /*
1129 * Find the next free tag meeting our constraints. If one is found,
1130 * perform the allocation.
1131 */
1132 for (cursor = &vm->vm_cursor, bt = TAILQ_NEXT(cursor, bt_seglist);
1133 bt != cursor; bt = TAILQ_NEXT(bt, bt_seglist)) {
1134 if (bt == NULL)
1135 bt = TAILQ_FIRST(&vm->vm_seglist);
1136 if (bt->bt_type == BT_TYPE_FREE && bt->bt_size >= size &&
1137 (error = vmem_fit(bt, size, align, phase, nocross,
1138 VMEM_ADDR_MIN, VMEM_ADDR_MAX, addrp)) == 0) {
1139 vmem_clip(vm, bt, *addrp, size);
1140 break;
1141 }
1142 }
1143
1144 /*
1145 * Try to coalesce free segments around the cursor. If we succeed, and
1146 * have not yet satisfied the allocation request, try again with the
1147 * newly coalesced segment.
1148 */
1149 if ((next = TAILQ_NEXT(cursor, bt_seglist)) != NULL &&
1150 (prev = TAILQ_PREV(cursor, vmem_seglist, bt_seglist)) != NULL &&
1151 next->bt_type == BT_TYPE_FREE && prev->bt_type == BT_TYPE_FREE &&
1152 prev->bt_start + prev->bt_size == next->bt_start) {
1153 prev->bt_size += next->bt_size;
1154 bt_remfree(vm, next);
1155 bt_remseg(vm, next);
1156
1157 /*
1158 * The coalesced segment might be able to satisfy our request.
1159 * If not, we might need to release it from the arena.
1160 */
1161 if (error == ENOMEM && prev->bt_size >= size &&
1162 (error = vmem_fit(prev, size, align, phase, nocross,
1163 VMEM_ADDR_MIN, VMEM_ADDR_MAX, addrp)) == 0) {
1164 vmem_clip(vm, prev, *addrp, size);
1165 bt = prev;
1166 } else
1167 (void)vmem_try_release(vm, prev, true);
1168 }
1169
1170 /*
1171 * If the allocation was successful, advance the cursor.
1172 */
1173 if (error == 0) {
1174 TAILQ_REMOVE(&vm->vm_seglist, cursor, bt_seglist);
1175 for (; bt != NULL && bt->bt_start < *addrp + size;
1176 bt = TAILQ_NEXT(bt, bt_seglist))
1177 ;
1178 if (bt != NULL)
1179 TAILQ_INSERT_BEFORE(bt, cursor, bt_seglist);
1180 else
1181 TAILQ_INSERT_HEAD(&vm->vm_seglist, cursor, bt_seglist);
1182 }
1183
1184 /*
1185 * Attempt to bring additional resources into the arena. If that fails
1186 * and M_WAITOK is specified, sleep waiting for resources to be freed.
1187 */
1188 if (error == ENOMEM && vmem_try_fetch(vm, size, align, flags))
1189 goto retry;
1190
1191 out:
1192 VMEM_UNLOCK(vm);
1193 return (error);
1194 }
1195
1196 /* ---- vmem API */
1197
1198 void
vmem_set_import(vmem_t * vm,vmem_import_t * importfn,vmem_release_t * releasefn,void * arg,vmem_size_t import_quantum)1199 vmem_set_import(vmem_t *vm, vmem_import_t *importfn,
1200 vmem_release_t *releasefn, void *arg, vmem_size_t import_quantum)
1201 {
1202
1203 VMEM_LOCK(vm);
1204 KASSERT(vm->vm_size == 0, ("%s: arena is non-empty", __func__));
1205 vm->vm_importfn = importfn;
1206 vm->vm_releasefn = releasefn;
1207 vm->vm_arg = arg;
1208 vm->vm_import_quantum = import_quantum;
1209 VMEM_UNLOCK(vm);
1210 }
1211
1212 void
vmem_set_limit(vmem_t * vm,vmem_size_t limit)1213 vmem_set_limit(vmem_t *vm, vmem_size_t limit)
1214 {
1215
1216 VMEM_LOCK(vm);
1217 vm->vm_limit = limit;
1218 VMEM_UNLOCK(vm);
1219 }
1220
1221 void
vmem_set_reclaim(vmem_t * vm,vmem_reclaim_t * reclaimfn)1222 vmem_set_reclaim(vmem_t *vm, vmem_reclaim_t *reclaimfn)
1223 {
1224
1225 VMEM_LOCK(vm);
1226 vm->vm_reclaimfn = reclaimfn;
1227 VMEM_UNLOCK(vm);
1228 }
1229
1230 /*
1231 * vmem_init: Initializes vmem arena.
1232 */
1233 vmem_t *
vmem_init(vmem_t * vm,const char * name,vmem_addr_t base,vmem_size_t size,vmem_size_t quantum,vmem_size_t qcache_max,int flags)1234 vmem_init(vmem_t *vm, const char *name, vmem_addr_t base, vmem_size_t size,
1235 vmem_size_t quantum, vmem_size_t qcache_max, int flags)
1236 {
1237 vmem_size_t i;
1238
1239 MPASS(quantum > 0);
1240 MPASS((quantum & (quantum - 1)) == 0);
1241
1242 bzero(vm, sizeof(*vm));
1243
1244 VMEM_CONDVAR_INIT(vm, name);
1245 VMEM_LOCK_INIT(vm, name);
1246 vm->vm_nfreetags = 0;
1247 LIST_INIT(&vm->vm_freetags);
1248 strlcpy(vm->vm_name, name, sizeof(vm->vm_name));
1249 vm->vm_quantum_mask = quantum - 1;
1250 vm->vm_quantum_shift = flsl(quantum) - 1;
1251 vm->vm_nbusytag = 0;
1252 vm->vm_size = 0;
1253 vm->vm_limit = 0;
1254 vm->vm_inuse = 0;
1255 qc_init(vm, qcache_max);
1256
1257 TAILQ_INIT(&vm->vm_seglist);
1258 vm->vm_cursor.bt_start = vm->vm_cursor.bt_size = 0;
1259 vm->vm_cursor.bt_type = BT_TYPE_CURSOR;
1260 TAILQ_INSERT_TAIL(&vm->vm_seglist, &vm->vm_cursor, bt_seglist);
1261
1262 for (i = 0; i < VMEM_MAXORDER; i++)
1263 LIST_INIT(&vm->vm_freelist[i]);
1264
1265 memset(&vm->vm_hash0, 0, sizeof(vm->vm_hash0));
1266 vm->vm_hashsize = VMEM_HASHSIZE_MIN;
1267 vm->vm_hashlist = vm->vm_hash0;
1268
1269 if (size != 0) {
1270 if (vmem_add(vm, base, size, flags) != 0) {
1271 vmem_destroy1(vm);
1272 return NULL;
1273 }
1274 }
1275
1276 mtx_lock(&vmem_list_lock);
1277 LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist);
1278 mtx_unlock(&vmem_list_lock);
1279
1280 return vm;
1281 }
1282
1283 /*
1284 * vmem_create: create an arena.
1285 */
1286 vmem_t *
vmem_create(const char * name,vmem_addr_t base,vmem_size_t size,vmem_size_t quantum,vmem_size_t qcache_max,int flags)1287 vmem_create(const char *name, vmem_addr_t base, vmem_size_t size,
1288 vmem_size_t quantum, vmem_size_t qcache_max, int flags)
1289 {
1290
1291 vmem_t *vm;
1292
1293 vm = uma_zalloc(vmem_zone, flags & (M_WAITOK|M_NOWAIT));
1294 if (vm == NULL)
1295 return (NULL);
1296 if (vmem_init(vm, name, base, size, quantum, qcache_max,
1297 flags) == NULL)
1298 return (NULL);
1299 return (vm);
1300 }
1301
1302 void
vmem_destroy(vmem_t * vm)1303 vmem_destroy(vmem_t *vm)
1304 {
1305
1306 mtx_lock(&vmem_list_lock);
1307 LIST_REMOVE(vm, vm_alllist);
1308 mtx_unlock(&vmem_list_lock);
1309
1310 vmem_destroy1(vm);
1311 }
1312
1313 vmem_size_t
vmem_roundup_size(vmem_t * vm,vmem_size_t size)1314 vmem_roundup_size(vmem_t *vm, vmem_size_t size)
1315 {
1316
1317 return (size + vm->vm_quantum_mask) & ~vm->vm_quantum_mask;
1318 }
1319
1320 /*
1321 * vmem_alloc: allocate resource from the arena.
1322 */
1323 int
vmem_alloc(vmem_t * vm,vmem_size_t size,int flags,vmem_addr_t * addrp)1324 vmem_alloc(vmem_t *vm, vmem_size_t size, int flags, vmem_addr_t *addrp)
1325 {
1326 const int strat __unused = flags & VMEM_FITMASK;
1327 qcache_t *qc;
1328
1329 flags &= VMEM_FLAGS;
1330 MPASS(size > 0);
1331 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT || strat == M_NEXTFIT);
1332 if ((flags & M_NOWAIT) == 0)
1333 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_alloc");
1334
1335 if (size <= vm->vm_qcache_max) {
1336 /*
1337 * Resource 0 cannot be cached, so avoid a blocking allocation
1338 * in qc_import() and give the vmem_xalloc() call below a chance
1339 * to return 0.
1340 */
1341 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift];
1342 *addrp = (vmem_addr_t)uma_zalloc(qc->qc_cache,
1343 (flags & ~M_WAITOK) | M_NOWAIT);
1344 if (__predict_true(*addrp != 0))
1345 return (0);
1346 }
1347
1348 return (vmem_xalloc(vm, size, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX,
1349 flags, addrp));
1350 }
1351
1352 int
vmem_xalloc(vmem_t * vm,const vmem_size_t size0,vmem_size_t align,const vmem_size_t phase,const vmem_size_t nocross,const vmem_addr_t minaddr,const vmem_addr_t maxaddr,int flags,vmem_addr_t * addrp)1353 vmem_xalloc(vmem_t *vm, const vmem_size_t size0, vmem_size_t align,
1354 const vmem_size_t phase, const vmem_size_t nocross,
1355 const vmem_addr_t minaddr, const vmem_addr_t maxaddr, int flags,
1356 vmem_addr_t *addrp)
1357 {
1358 const vmem_size_t size = vmem_roundup_size(vm, size0);
1359 struct vmem_freelist *list;
1360 struct vmem_freelist *first;
1361 struct vmem_freelist *end;
1362 bt_t *bt;
1363 int error;
1364 int strat;
1365
1366 flags &= VMEM_FLAGS;
1367 strat = flags & VMEM_FITMASK;
1368 MPASS(size0 > 0);
1369 MPASS(size > 0);
1370 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT || strat == M_NEXTFIT);
1371 MPASS((flags & (M_NOWAIT|M_WAITOK)) != (M_NOWAIT|M_WAITOK));
1372 if ((flags & M_NOWAIT) == 0)
1373 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_xalloc");
1374 MPASS((align & vm->vm_quantum_mask) == 0);
1375 MPASS((align & (align - 1)) == 0);
1376 MPASS((phase & vm->vm_quantum_mask) == 0);
1377 MPASS((nocross & vm->vm_quantum_mask) == 0);
1378 MPASS((nocross & (nocross - 1)) == 0);
1379 MPASS((align == 0 && phase == 0) || phase < align);
1380 MPASS(nocross == 0 || nocross >= size);
1381 MPASS(minaddr <= maxaddr);
1382 MPASS(!VMEM_CROSS_P(phase, phase + size - 1, nocross));
1383 if (strat == M_NEXTFIT)
1384 MPASS(minaddr == VMEM_ADDR_MIN && maxaddr == VMEM_ADDR_MAX);
1385
1386 if (align == 0)
1387 align = vm->vm_quantum_mask + 1;
1388 *addrp = 0;
1389
1390 /*
1391 * Next-fit allocations don't use the freelists.
1392 */
1393 if (strat == M_NEXTFIT)
1394 return (vmem_xalloc_nextfit(vm, size0, align, phase, nocross,
1395 flags, addrp));
1396
1397 end = &vm->vm_freelist[VMEM_MAXORDER];
1398 /*
1399 * choose a free block from which we allocate.
1400 */
1401 first = bt_freehead_toalloc(vm, size, strat);
1402 VMEM_LOCK(vm);
1403
1404 /*
1405 * Make sure we have enough tags to complete the operation.
1406 */
1407 error = bt_fill(vm, flags);
1408 if (error != 0)
1409 goto out;
1410 for (;;) {
1411 /*
1412 * Scan freelists looking for a tag that satisfies the
1413 * allocation. If we're doing BESTFIT we may encounter
1414 * sizes below the request. If we're doing FIRSTFIT we
1415 * inspect only the first element from each list.
1416 */
1417 for (list = first; list < end; list++) {
1418 LIST_FOREACH(bt, list, bt_freelist) {
1419 if (bt->bt_size >= size) {
1420 error = vmem_fit(bt, size, align, phase,
1421 nocross, minaddr, maxaddr, addrp);
1422 if (error == 0) {
1423 vmem_clip(vm, bt, *addrp, size);
1424 goto out;
1425 }
1426 }
1427 /* FIRST skips to the next list. */
1428 if (strat == M_FIRSTFIT)
1429 break;
1430 }
1431 }
1432
1433 /*
1434 * Retry if the fast algorithm failed.
1435 */
1436 if (strat == M_FIRSTFIT) {
1437 strat = M_BESTFIT;
1438 first = bt_freehead_toalloc(vm, size, strat);
1439 continue;
1440 }
1441
1442 /*
1443 * Try a few measures to bring additional resources into the
1444 * arena. If all else fails, we will sleep waiting for
1445 * resources to be freed.
1446 */
1447 if (!vmem_try_fetch(vm, size, align, flags)) {
1448 error = ENOMEM;
1449 break;
1450 }
1451 }
1452 out:
1453 VMEM_UNLOCK(vm);
1454 if (error != 0 && (flags & M_NOWAIT) == 0)
1455 panic("failed to allocate waiting allocation\n");
1456
1457 return (error);
1458 }
1459
1460 /*
1461 * vmem_free: free the resource to the arena.
1462 */
1463 void
vmem_free(vmem_t * vm,vmem_addr_t addr,vmem_size_t size)1464 vmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
1465 {
1466 qcache_t *qc;
1467 MPASS(size > 0);
1468
1469 if (size <= vm->vm_qcache_max &&
1470 __predict_true(addr >= VMEM_ADDR_QCACHE_MIN)) {
1471 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift];
1472 uma_zfree(qc->qc_cache, (void *)addr);
1473 } else
1474 vmem_xfree(vm, addr, size);
1475 }
1476
1477 void
vmem_xfree(vmem_t * vm,vmem_addr_t addr,vmem_size_t size __unused)1478 vmem_xfree(vmem_t *vm, vmem_addr_t addr, vmem_size_t size __unused)
1479 {
1480 bt_t *bt;
1481 bt_t *t;
1482
1483 MPASS(size > 0);
1484
1485 VMEM_LOCK(vm);
1486 bt = bt_lookupbusy(vm, addr);
1487 MPASS(bt != NULL);
1488 MPASS(bt->bt_start == addr);
1489 MPASS(bt->bt_size == vmem_roundup_size(vm, size) ||
1490 bt->bt_size - vmem_roundup_size(vm, size) <= vm->vm_quantum_mask);
1491 MPASS(bt->bt_type == BT_TYPE_BUSY);
1492 bt_rembusy(vm, bt);
1493 bt->bt_type = BT_TYPE_FREE;
1494
1495 /* coalesce */
1496 t = TAILQ_NEXT(bt, bt_seglist);
1497 if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1498 MPASS(BT_END(bt) < t->bt_start); /* YYY */
1499 bt->bt_size += t->bt_size;
1500 bt_remfree(vm, t);
1501 bt_remseg(vm, t);
1502 }
1503 t = TAILQ_PREV(bt, vmem_seglist, bt_seglist);
1504 if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1505 MPASS(BT_END(t) < bt->bt_start); /* YYY */
1506 bt->bt_size += t->bt_size;
1507 bt->bt_start = t->bt_start;
1508 bt_remfree(vm, t);
1509 bt_remseg(vm, t);
1510 }
1511
1512 if (!vmem_try_release(vm, bt, false)) {
1513 bt_insfree(vm, bt);
1514 VMEM_CONDVAR_BROADCAST(vm);
1515 bt_freetrim(vm, BT_MAXFREE);
1516 }
1517 }
1518
1519 /*
1520 * vmem_add:
1521 *
1522 */
1523 int
vmem_add(vmem_t * vm,vmem_addr_t addr,vmem_size_t size,int flags)1524 vmem_add(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int flags)
1525 {
1526 int error;
1527
1528 flags &= VMEM_FLAGS;
1529
1530 VMEM_LOCK(vm);
1531 error = bt_fill(vm, flags);
1532 if (error == 0)
1533 vmem_add1(vm, addr, size, BT_TYPE_SPAN_STATIC);
1534 VMEM_UNLOCK(vm);
1535
1536 return (error);
1537 }
1538
1539 /*
1540 * vmem_size: information about arenas size
1541 */
1542 vmem_size_t
vmem_size(vmem_t * vm,int typemask)1543 vmem_size(vmem_t *vm, int typemask)
1544 {
1545 int i;
1546
1547 switch (typemask) {
1548 case VMEM_ALLOC:
1549 return vm->vm_inuse;
1550 case VMEM_FREE:
1551 return vm->vm_size - vm->vm_inuse;
1552 case VMEM_FREE|VMEM_ALLOC:
1553 return vm->vm_size;
1554 case VMEM_MAXFREE:
1555 VMEM_LOCK(vm);
1556 for (i = VMEM_MAXORDER - 1; i >= 0; i--) {
1557 if (LIST_EMPTY(&vm->vm_freelist[i]))
1558 continue;
1559 VMEM_UNLOCK(vm);
1560 return ((vmem_size_t)ORDER2SIZE(i) <<
1561 vm->vm_quantum_shift);
1562 }
1563 VMEM_UNLOCK(vm);
1564 return (0);
1565 default:
1566 panic("vmem_size");
1567 }
1568 }
1569
1570 /* ---- debug */
1571
1572 #if defined(DDB) || defined(DIAGNOSTIC)
1573
1574 static void bt_dump(const bt_t *, int (*)(const char *, ...)
1575 __printflike(1, 2));
1576
1577 static const char *
bt_type_string(int type)1578 bt_type_string(int type)
1579 {
1580
1581 switch (type) {
1582 case BT_TYPE_BUSY:
1583 return "busy";
1584 case BT_TYPE_FREE:
1585 return "free";
1586 case BT_TYPE_SPAN:
1587 return "span";
1588 case BT_TYPE_SPAN_STATIC:
1589 return "static span";
1590 case BT_TYPE_CURSOR:
1591 return "cursor";
1592 default:
1593 break;
1594 }
1595 return "BOGUS";
1596 }
1597
1598 static void
bt_dump(const bt_t * bt,int (* pr)(const char *,...))1599 bt_dump(const bt_t *bt, int (*pr)(const char *, ...))
1600 {
1601
1602 (*pr)("\t%p: %jx %jx, %d(%s)\n",
1603 bt, (intmax_t)bt->bt_start, (intmax_t)bt->bt_size,
1604 bt->bt_type, bt_type_string(bt->bt_type));
1605 }
1606
1607 static void
1608 vmem_dump(const vmem_t *vm , int (*pr)(const char *, ...) __printflike(1, 2))
1609 {
1610 const bt_t *bt;
1611 int i;
1612
1613 (*pr)("vmem %p '%s'\n", vm, vm->vm_name);
1614 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1615 bt_dump(bt, pr);
1616 }
1617
1618 for (i = 0; i < VMEM_MAXORDER; i++) {
1619 const struct vmem_freelist *fl = &vm->vm_freelist[i];
1620
1621 if (LIST_EMPTY(fl)) {
1622 continue;
1623 }
1624
1625 (*pr)("freelist[%d]\n", i);
LIST_FOREACH(bt,fl,bt_freelist)1626 LIST_FOREACH(bt, fl, bt_freelist) {
1627 bt_dump(bt, pr);
1628 }
1629 }
1630 }
1631
1632 #endif /* defined(DDB) || defined(DIAGNOSTIC) */
1633
1634 #if defined(DDB)
1635 #include <ddb/ddb.h>
1636
1637 static bt_t *
vmem_whatis_lookup(vmem_t * vm,vmem_addr_t addr)1638 vmem_whatis_lookup(vmem_t *vm, vmem_addr_t addr)
1639 {
1640 bt_t *bt;
1641
1642 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1643 if (BT_ISSPAN_P(bt)) {
1644 continue;
1645 }
1646 if (bt->bt_start <= addr && addr <= BT_END(bt)) {
1647 return bt;
1648 }
1649 }
1650
1651 return NULL;
1652 }
1653
1654 void
vmem_whatis(vmem_addr_t addr,int (* pr)(const char *,...))1655 vmem_whatis(vmem_addr_t addr, int (*pr)(const char *, ...))
1656 {
1657 vmem_t *vm;
1658
1659 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1660 bt_t *bt;
1661
1662 bt = vmem_whatis_lookup(vm, addr);
1663 if (bt == NULL) {
1664 continue;
1665 }
1666 (*pr)("%p is %p+%zu in VMEM '%s' (%s)\n",
1667 (void *)addr, (void *)bt->bt_start,
1668 (vmem_size_t)(addr - bt->bt_start), vm->vm_name,
1669 (bt->bt_type == BT_TYPE_BUSY) ? "allocated" : "free");
1670 }
1671 }
1672
1673 void
vmem_printall(const char * modif,int (* pr)(const char *,...))1674 vmem_printall(const char *modif, int (*pr)(const char *, ...))
1675 {
1676 const vmem_t *vm;
1677
1678 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1679 vmem_dump(vm, pr);
1680 }
1681 }
1682
1683 void
vmem_print(vmem_addr_t addr,const char * modif,int (* pr)(const char *,...))1684 vmem_print(vmem_addr_t addr, const char *modif, int (*pr)(const char *, ...))
1685 {
1686 const vmem_t *vm = (const void *)addr;
1687
1688 vmem_dump(vm, pr);
1689 }
1690
DB_SHOW_COMMAND(vmemdump,vmemdump)1691 DB_SHOW_COMMAND(vmemdump, vmemdump)
1692 {
1693
1694 if (!have_addr) {
1695 db_printf("usage: show vmemdump <addr>\n");
1696 return;
1697 }
1698
1699 vmem_dump((const vmem_t *)addr, db_printf);
1700 }
1701
DB_SHOW_ALL_COMMAND(vmemdump,vmemdumpall)1702 DB_SHOW_ALL_COMMAND(vmemdump, vmemdumpall)
1703 {
1704 const vmem_t *vm;
1705
1706 LIST_FOREACH(vm, &vmem_list, vm_alllist)
1707 vmem_dump(vm, db_printf);
1708 }
1709
DB_SHOW_COMMAND(vmem,vmem_summ)1710 DB_SHOW_COMMAND(vmem, vmem_summ)
1711 {
1712 const vmem_t *vm = (const void *)addr;
1713 const bt_t *bt;
1714 size_t ft[VMEM_MAXORDER], ut[VMEM_MAXORDER];
1715 size_t fs[VMEM_MAXORDER], us[VMEM_MAXORDER];
1716 int ord;
1717
1718 if (!have_addr) {
1719 db_printf("usage: show vmem <addr>\n");
1720 return;
1721 }
1722
1723 db_printf("vmem %p '%s'\n", vm, vm->vm_name);
1724 db_printf("\tquantum:\t%zu\n", vm->vm_quantum_mask + 1);
1725 db_printf("\tsize:\t%zu\n", vm->vm_size);
1726 db_printf("\tinuse:\t%zu\n", vm->vm_inuse);
1727 db_printf("\tfree:\t%zu\n", vm->vm_size - vm->vm_inuse);
1728 db_printf("\tbusy tags:\t%d\n", vm->vm_nbusytag);
1729 db_printf("\tfree tags:\t%d\n", vm->vm_nfreetags);
1730
1731 memset(&ft, 0, sizeof(ft));
1732 memset(&ut, 0, sizeof(ut));
1733 memset(&fs, 0, sizeof(fs));
1734 memset(&us, 0, sizeof(us));
1735 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1736 ord = SIZE2ORDER(bt->bt_size >> vm->vm_quantum_shift);
1737 if (bt->bt_type == BT_TYPE_BUSY) {
1738 ut[ord]++;
1739 us[ord] += bt->bt_size;
1740 } else if (bt->bt_type == BT_TYPE_FREE) {
1741 ft[ord]++;
1742 fs[ord] += bt->bt_size;
1743 }
1744 }
1745 db_printf("\t\t\tinuse\tsize\t\tfree\tsize\n");
1746 for (ord = 0; ord < VMEM_MAXORDER; ord++) {
1747 if (ut[ord] == 0 && ft[ord] == 0)
1748 continue;
1749 db_printf("\t%-15zu %zu\t%-15zu %zu\t%-16zu\n",
1750 ORDER2SIZE(ord) << vm->vm_quantum_shift,
1751 ut[ord], us[ord], ft[ord], fs[ord]);
1752 }
1753 }
1754
DB_SHOW_ALL_COMMAND(vmem,vmem_summall)1755 DB_SHOW_ALL_COMMAND(vmem, vmem_summall)
1756 {
1757 const vmem_t *vm;
1758
1759 LIST_FOREACH(vm, &vmem_list, vm_alllist)
1760 vmem_summ((db_expr_t)vm, TRUE, count, modif);
1761 }
1762 #endif /* defined(DDB) */
1763
1764 #define vmem_printf printf
1765
1766 #if defined(DIAGNOSTIC)
1767
1768 static bool
vmem_check_sanity(vmem_t * vm)1769 vmem_check_sanity(vmem_t *vm)
1770 {
1771 const bt_t *bt, *bt2;
1772
1773 MPASS(vm != NULL);
1774
1775 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1776 if (bt->bt_start > BT_END(bt)) {
1777 printf("corrupted tag\n");
1778 bt_dump(bt, vmem_printf);
1779 return false;
1780 }
1781 }
1782 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1783 if (bt->bt_type == BT_TYPE_CURSOR) {
1784 if (bt->bt_start != 0 || bt->bt_size != 0) {
1785 printf("corrupted cursor\n");
1786 return false;
1787 }
1788 continue;
1789 }
1790 TAILQ_FOREACH(bt2, &vm->vm_seglist, bt_seglist) {
1791 if (bt == bt2) {
1792 continue;
1793 }
1794 if (bt2->bt_type == BT_TYPE_CURSOR) {
1795 continue;
1796 }
1797 if (BT_ISSPAN_P(bt) != BT_ISSPAN_P(bt2)) {
1798 continue;
1799 }
1800 if (bt->bt_start <= BT_END(bt2) &&
1801 bt2->bt_start <= BT_END(bt)) {
1802 printf("overwrapped tags\n");
1803 bt_dump(bt, vmem_printf);
1804 bt_dump(bt2, vmem_printf);
1805 return false;
1806 }
1807 }
1808 }
1809
1810 return true;
1811 }
1812
1813 static void
vmem_check(vmem_t * vm)1814 vmem_check(vmem_t *vm)
1815 {
1816
1817 if (!vmem_check_sanity(vm)) {
1818 panic("insanity vmem %p", vm);
1819 }
1820 }
1821
1822 #endif /* defined(DIAGNOSTIC) */
1823