FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_vmem.c
1 /*-
2 * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi,
3 * Copyright (c) 2013 EMC Corp.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 /*
29 * From:
30 * $NetBSD: vmem_impl.h,v 1.2 2013/01/29 21:26:24 para Exp $
31 * $NetBSD: subr_vmem.c,v 1.83 2013/03/06 11:20:10 yamt Exp $
32 */
33
34 /*
35 * reference:
36 * - Magazines and Vmem: Extending the Slab Allocator
37 * to Many CPUs and Arbitrary Resources
38 * http://www.usenix.org/event/usenix01/bonwick.html
39 */
40
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD: releng/11.1/sys/kern/subr_vmem.c 299494 2016-05-11 23:16:11Z cem $");
43
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
61 #include "opt_vm.h"
62
63 #include <vm/uma.h>
64 #include <vm/vm.h>
65 #include <vm/pmap.h>
66 #include <vm/vm_map.h>
67 #include <vm/vm_object.h>
68 #include <vm/vm_kern.h>
69 #include <vm/vm_extern.h>
70 #include <vm/vm_param.h>
71 #include <vm/vm_pageout.h>
72
73 #define VMEM_OPTORDER 5
74 #define VMEM_OPTVALUE (1 << VMEM_OPTORDER)
75 #define VMEM_MAXORDER \
76 (VMEM_OPTVALUE - 1 + sizeof(vmem_size_t) * NBBY - VMEM_OPTORDER)
77
78 #define VMEM_HASHSIZE_MIN 16
79 #define VMEM_HASHSIZE_MAX 131072
80
81 #define VMEM_QCACHE_IDX_MAX 16
82
83 #define VMEM_FITMASK (M_BESTFIT | M_FIRSTFIT)
84
85 #define VMEM_FLAGS \
86 (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM | M_BESTFIT | M_FIRSTFIT)
87
88 #define BT_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM)
89
90 #define QC_NAME_MAX 16
91
92 /*
93 * Data structures private to vmem.
94 */
95 MALLOC_DEFINE(M_VMEM, "vmem", "vmem internal structures");
96
97 typedef struct vmem_btag bt_t;
98
99 TAILQ_HEAD(vmem_seglist, vmem_btag);
100 LIST_HEAD(vmem_freelist, vmem_btag);
101 LIST_HEAD(vmem_hashlist, vmem_btag);
102
103 struct qcache {
104 uma_zone_t qc_cache;
105 vmem_t *qc_vmem;
106 vmem_size_t qc_size;
107 char qc_name[QC_NAME_MAX];
108 };
109 typedef struct qcache qcache_t;
110 #define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache))
111
112 #define VMEM_NAME_MAX 16
113
114 /* vmem arena */
115 struct vmem {
116 struct mtx_padalign vm_lock;
117 struct cv vm_cv;
118 char vm_name[VMEM_NAME_MAX+1];
119 LIST_ENTRY(vmem) vm_alllist;
120 struct vmem_hashlist vm_hash0[VMEM_HASHSIZE_MIN];
121 struct vmem_freelist vm_freelist[VMEM_MAXORDER];
122 struct vmem_seglist vm_seglist;
123 struct vmem_hashlist *vm_hashlist;
124 vmem_size_t vm_hashsize;
125
126 /* Constant after init */
127 vmem_size_t vm_qcache_max;
128 vmem_size_t vm_quantum_mask;
129 vmem_size_t vm_import_quantum;
130 int vm_quantum_shift;
131
132 /* Written on alloc/free */
133 LIST_HEAD(, vmem_btag) vm_freetags;
134 int vm_nfreetags;
135 int vm_nbusytag;
136 vmem_size_t vm_inuse;
137 vmem_size_t vm_size;
138
139 /* Used on import. */
140 vmem_import_t *vm_importfn;
141 vmem_release_t *vm_releasefn;
142 void *vm_arg;
143
144 /* Space exhaustion callback. */
145 vmem_reclaim_t *vm_reclaimfn;
146
147 /* quantum cache */
148 qcache_t vm_qcache[VMEM_QCACHE_IDX_MAX];
149 };
150
151 /* boundary tag */
152 struct vmem_btag {
153 TAILQ_ENTRY(vmem_btag) bt_seglist;
154 union {
155 LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */
156 LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */
157 } bt_u;
158 #define bt_hashlist bt_u.u_hashlist
159 #define bt_freelist bt_u.u_freelist
160 vmem_addr_t bt_start;
161 vmem_size_t bt_size;
162 int bt_type;
163 };
164
165 #define BT_TYPE_SPAN 1 /* Allocated from importfn */
166 #define BT_TYPE_SPAN_STATIC 2 /* vmem_add() or create. */
167 #define BT_TYPE_FREE 3 /* Available space. */
168 #define BT_TYPE_BUSY 4 /* Used space. */
169 #define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC)
170
171 #define BT_END(bt) ((bt)->bt_start + (bt)->bt_size - 1)
172
173 #if defined(DIAGNOSTIC)
174 static int enable_vmem_check = 1;
175 SYSCTL_INT(_debug, OID_AUTO, vmem_check, CTLFLAG_RWTUN,
176 &enable_vmem_check, 0, "Enable vmem check");
177 static void vmem_check(vmem_t *);
178 #endif
179
180 static struct callout vmem_periodic_ch;
181 static int vmem_periodic_interval;
182 static struct task vmem_periodic_wk;
183
184 static struct mtx_padalign vmem_list_lock;
185 static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list);
186
187 /* ---- misc */
188 #define VMEM_CONDVAR_INIT(vm, wchan) cv_init(&vm->vm_cv, wchan)
189 #define VMEM_CONDVAR_DESTROY(vm) cv_destroy(&vm->vm_cv)
190 #define VMEM_CONDVAR_WAIT(vm) cv_wait(&vm->vm_cv, &vm->vm_lock)
191 #define VMEM_CONDVAR_BROADCAST(vm) cv_broadcast(&vm->vm_cv)
192
193
194 #define VMEM_LOCK(vm) mtx_lock(&vm->vm_lock)
195 #define VMEM_TRYLOCK(vm) mtx_trylock(&vm->vm_lock)
196 #define VMEM_UNLOCK(vm) mtx_unlock(&vm->vm_lock)
197 #define VMEM_LOCK_INIT(vm, name) mtx_init(&vm->vm_lock, (name), NULL, MTX_DEF)
198 #define VMEM_LOCK_DESTROY(vm) mtx_destroy(&vm->vm_lock)
199 #define VMEM_ASSERT_LOCKED(vm) mtx_assert(&vm->vm_lock, MA_OWNED);
200
201 #define VMEM_ALIGNUP(addr, align) (-(-(addr) & -(align)))
202
203 #define VMEM_CROSS_P(addr1, addr2, boundary) \
204 ((((addr1) ^ (addr2)) & -(boundary)) != 0)
205
206 #define ORDER2SIZE(order) ((order) < VMEM_OPTVALUE ? ((order) + 1) : \
207 (vmem_size_t)1 << ((order) - (VMEM_OPTVALUE - VMEM_OPTORDER - 1)))
208 #define SIZE2ORDER(size) ((size) <= VMEM_OPTVALUE ? ((size) - 1) : \
209 (flsl(size) + (VMEM_OPTVALUE - VMEM_OPTORDER - 2)))
210
211 /*
212 * Maximum number of boundary tags that may be required to satisfy an
213 * allocation. Two may be required to import. Another two may be
214 * required to clip edges.
215 */
216 #define BT_MAXALLOC 4
217
218 /*
219 * Max free limits the number of locally cached boundary tags. We
220 * just want to avoid hitting the zone allocator for every call.
221 */
222 #define BT_MAXFREE (BT_MAXALLOC * 8)
223
224 /* Allocator for boundary tags. */
225 static uma_zone_t vmem_bt_zone;
226
227 /* boot time arena storage. */
228 static struct vmem kernel_arena_storage;
229 static struct vmem kmem_arena_storage;
230 static struct vmem buffer_arena_storage;
231 static struct vmem transient_arena_storage;
232 vmem_t *kernel_arena = &kernel_arena_storage;
233 vmem_t *kmem_arena = &kmem_arena_storage;
234 vmem_t *buffer_arena = &buffer_arena_storage;
235 vmem_t *transient_arena = &transient_arena_storage;
236
237 #ifdef DEBUG_MEMGUARD
238 static struct vmem memguard_arena_storage;
239 vmem_t *memguard_arena = &memguard_arena_storage;
240 #endif
241
242 /*
243 * Fill the vmem's boundary tag cache. We guarantee that boundary tag
244 * allocation will not fail once bt_fill() passes. To do so we cache
245 * at least the maximum possible tag allocations in the arena.
246 */
247 static int
248 bt_fill(vmem_t *vm, int flags)
249 {
250 bt_t *bt;
251
252 VMEM_ASSERT_LOCKED(vm);
253
254 /*
255 * Only allow the kmem arena to dip into reserve tags. It is the
256 * vmem where new tags come from.
257 */
258 flags &= BT_FLAGS;
259 if (vm != kmem_arena)
260 flags &= ~M_USE_RESERVE;
261
262 /*
263 * Loop until we meet the reserve. To minimize the lock shuffle
264 * and prevent simultaneous fills we first try a NOWAIT regardless
265 * of the caller's flags. Specify M_NOVM so we don't recurse while
266 * holding a vmem lock.
267 */
268 while (vm->vm_nfreetags < BT_MAXALLOC) {
269 bt = uma_zalloc(vmem_bt_zone,
270 (flags & M_USE_RESERVE) | M_NOWAIT | M_NOVM);
271 if (bt == NULL) {
272 VMEM_UNLOCK(vm);
273 bt = uma_zalloc(vmem_bt_zone, flags);
274 VMEM_LOCK(vm);
275 if (bt == NULL && (flags & M_NOWAIT) != 0)
276 break;
277 }
278 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
279 vm->vm_nfreetags++;
280 }
281
282 if (vm->vm_nfreetags < BT_MAXALLOC)
283 return ENOMEM;
284
285 return 0;
286 }
287
288 /*
289 * Pop a tag off of the freetag stack.
290 */
291 static bt_t *
292 bt_alloc(vmem_t *vm)
293 {
294 bt_t *bt;
295
296 VMEM_ASSERT_LOCKED(vm);
297 bt = LIST_FIRST(&vm->vm_freetags);
298 MPASS(bt != NULL);
299 LIST_REMOVE(bt, bt_freelist);
300 vm->vm_nfreetags--;
301
302 return bt;
303 }
304
305 /*
306 * Trim the per-vmem free list. Returns with the lock released to
307 * avoid allocator recursions.
308 */
309 static void
310 bt_freetrim(vmem_t *vm, int freelimit)
311 {
312 LIST_HEAD(, vmem_btag) freetags;
313 bt_t *bt;
314
315 LIST_INIT(&freetags);
316 VMEM_ASSERT_LOCKED(vm);
317 while (vm->vm_nfreetags > freelimit) {
318 bt = LIST_FIRST(&vm->vm_freetags);
319 LIST_REMOVE(bt, bt_freelist);
320 vm->vm_nfreetags--;
321 LIST_INSERT_HEAD(&freetags, bt, bt_freelist);
322 }
323 VMEM_UNLOCK(vm);
324 while ((bt = LIST_FIRST(&freetags)) != NULL) {
325 LIST_REMOVE(bt, bt_freelist);
326 uma_zfree(vmem_bt_zone, bt);
327 }
328 }
329
330 static inline void
331 bt_free(vmem_t *vm, bt_t *bt)
332 {
333
334 VMEM_ASSERT_LOCKED(vm);
335 MPASS(LIST_FIRST(&vm->vm_freetags) != bt);
336 LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist);
337 vm->vm_nfreetags++;
338 }
339
340 /*
341 * freelist[0] ... [1, 1]
342 * freelist[1] ... [2, 2]
343 * :
344 * freelist[29] ... [30, 30]
345 * freelist[30] ... [31, 31]
346 * freelist[31] ... [32, 63]
347 * freelist[33] ... [64, 127]
348 * :
349 * freelist[n] ... [(1 << (n - 26)), (1 << (n - 25)) - 1]
350 * :
351 */
352
353 static struct vmem_freelist *
354 bt_freehead_tofree(vmem_t *vm, vmem_size_t size)
355 {
356 const vmem_size_t qsize = size >> vm->vm_quantum_shift;
357 const int idx = SIZE2ORDER(qsize);
358
359 MPASS(size != 0 && qsize != 0);
360 MPASS((size & vm->vm_quantum_mask) == 0);
361 MPASS(idx >= 0);
362 MPASS(idx < VMEM_MAXORDER);
363
364 return &vm->vm_freelist[idx];
365 }
366
367 /*
368 * bt_freehead_toalloc: return the freelist for the given size and allocation
369 * strategy.
370 *
371 * For M_FIRSTFIT, return the list in which any blocks are large enough
372 * for the requested size. otherwise, return the list which can have blocks
373 * large enough for the requested size.
374 */
375 static struct vmem_freelist *
376 bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, int strat)
377 {
378 const vmem_size_t qsize = size >> vm->vm_quantum_shift;
379 int idx = SIZE2ORDER(qsize);
380
381 MPASS(size != 0 && qsize != 0);
382 MPASS((size & vm->vm_quantum_mask) == 0);
383
384 if (strat == M_FIRSTFIT && ORDER2SIZE(idx) != qsize) {
385 idx++;
386 /* check too large request? */
387 }
388 MPASS(idx >= 0);
389 MPASS(idx < VMEM_MAXORDER);
390
391 return &vm->vm_freelist[idx];
392 }
393
394 /* ---- boundary tag hash */
395
396 static struct vmem_hashlist *
397 bt_hashhead(vmem_t *vm, vmem_addr_t addr)
398 {
399 struct vmem_hashlist *list;
400 unsigned int hash;
401
402 hash = hash32_buf(&addr, sizeof(addr), 0);
403 list = &vm->vm_hashlist[hash % vm->vm_hashsize];
404
405 return list;
406 }
407
408 static bt_t *
409 bt_lookupbusy(vmem_t *vm, vmem_addr_t addr)
410 {
411 struct vmem_hashlist *list;
412 bt_t *bt;
413
414 VMEM_ASSERT_LOCKED(vm);
415 list = bt_hashhead(vm, addr);
416 LIST_FOREACH(bt, list, bt_hashlist) {
417 if (bt->bt_start == addr) {
418 break;
419 }
420 }
421
422 return bt;
423 }
424
425 static void
426 bt_rembusy(vmem_t *vm, bt_t *bt)
427 {
428
429 VMEM_ASSERT_LOCKED(vm);
430 MPASS(vm->vm_nbusytag > 0);
431 vm->vm_inuse -= bt->bt_size;
432 vm->vm_nbusytag--;
433 LIST_REMOVE(bt, bt_hashlist);
434 }
435
436 static void
437 bt_insbusy(vmem_t *vm, bt_t *bt)
438 {
439 struct vmem_hashlist *list;
440
441 VMEM_ASSERT_LOCKED(vm);
442 MPASS(bt->bt_type == BT_TYPE_BUSY);
443
444 list = bt_hashhead(vm, bt->bt_start);
445 LIST_INSERT_HEAD(list, bt, bt_hashlist);
446 vm->vm_nbusytag++;
447 vm->vm_inuse += bt->bt_size;
448 }
449
450 /* ---- boundary tag list */
451
452 static void
453 bt_remseg(vmem_t *vm, bt_t *bt)
454 {
455
456 TAILQ_REMOVE(&vm->vm_seglist, bt, bt_seglist);
457 bt_free(vm, bt);
458 }
459
460 static void
461 bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev)
462 {
463
464 TAILQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist);
465 }
466
467 static void
468 bt_insseg_tail(vmem_t *vm, bt_t *bt)
469 {
470
471 TAILQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist);
472 }
473
474 static void
475 bt_remfree(vmem_t *vm, bt_t *bt)
476 {
477
478 MPASS(bt->bt_type == BT_TYPE_FREE);
479
480 LIST_REMOVE(bt, bt_freelist);
481 }
482
483 static void
484 bt_insfree(vmem_t *vm, bt_t *bt)
485 {
486 struct vmem_freelist *list;
487
488 list = bt_freehead_tofree(vm, bt->bt_size);
489 LIST_INSERT_HEAD(list, bt, bt_freelist);
490 }
491
492 /* ---- vmem internal functions */
493
494 /*
495 * Import from the arena into the quantum cache in UMA.
496 */
497 static int
498 qc_import(void *arg, void **store, int cnt, int flags)
499 {
500 qcache_t *qc;
501 vmem_addr_t addr;
502 int i;
503
504 qc = arg;
505 if ((flags & VMEM_FITMASK) == 0)
506 flags |= M_BESTFIT;
507 for (i = 0; i < cnt; i++) {
508 if (vmem_xalloc(qc->qc_vmem, qc->qc_size, 0, 0, 0,
509 VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags, &addr) != 0)
510 break;
511 store[i] = (void *)addr;
512 /* Only guarantee one allocation. */
513 flags &= ~M_WAITOK;
514 flags |= M_NOWAIT;
515 }
516 return i;
517 }
518
519 /*
520 * Release memory from the UMA cache to the arena.
521 */
522 static void
523 qc_release(void *arg, void **store, int cnt)
524 {
525 qcache_t *qc;
526 int i;
527
528 qc = arg;
529 for (i = 0; i < cnt; i++)
530 vmem_xfree(qc->qc_vmem, (vmem_addr_t)store[i], qc->qc_size);
531 }
532
533 static void
534 qc_init(vmem_t *vm, vmem_size_t qcache_max)
535 {
536 qcache_t *qc;
537 vmem_size_t size;
538 int qcache_idx_max;
539 int i;
540
541 MPASS((qcache_max & vm->vm_quantum_mask) == 0);
542 qcache_idx_max = MIN(qcache_max >> vm->vm_quantum_shift,
543 VMEM_QCACHE_IDX_MAX);
544 vm->vm_qcache_max = qcache_idx_max << vm->vm_quantum_shift;
545 for (i = 0; i < qcache_idx_max; i++) {
546 qc = &vm->vm_qcache[i];
547 size = (i + 1) << vm->vm_quantum_shift;
548 snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu",
549 vm->vm_name, size);
550 qc->qc_vmem = vm;
551 qc->qc_size = size;
552 qc->qc_cache = uma_zcache_create(qc->qc_name, size,
553 NULL, NULL, NULL, NULL, qc_import, qc_release, qc,
554 UMA_ZONE_VM);
555 MPASS(qc->qc_cache);
556 }
557 }
558
559 static void
560 qc_destroy(vmem_t *vm)
561 {
562 int qcache_idx_max;
563 int i;
564
565 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
566 for (i = 0; i < qcache_idx_max; i++)
567 uma_zdestroy(vm->vm_qcache[i].qc_cache);
568 }
569
570 static void
571 qc_drain(vmem_t *vm)
572 {
573 int qcache_idx_max;
574 int i;
575
576 qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift;
577 for (i = 0; i < qcache_idx_max; i++)
578 zone_drain(vm->vm_qcache[i].qc_cache);
579 }
580
581 #ifndef UMA_MD_SMALL_ALLOC
582
583 static struct mtx_padalign vmem_bt_lock;
584
585 /*
586 * vmem_bt_alloc: Allocate a new page of boundary tags.
587 *
588 * On architectures with uma_small_alloc there is no recursion; no address
589 * space need be allocated to allocate boundary tags. For the others, we
590 * must handle recursion. Boundary tags are necessary to allocate new
591 * boundary tags.
592 *
593 * UMA guarantees that enough tags are held in reserve to allocate a new
594 * page of kva. We dip into this reserve by specifying M_USE_RESERVE only
595 * when allocating the page to hold new boundary tags. In this way the
596 * reserve is automatically filled by the allocation that uses the reserve.
597 *
598 * We still have to guarantee that the new tags are allocated atomically since
599 * many threads may try concurrently. The bt_lock provides this guarantee.
600 * We convert WAITOK allocations to NOWAIT and then handle the blocking here
601 * on failure. It's ok to return NULL for a WAITOK allocation as UMA will
602 * loop again after checking to see if we lost the race to allocate.
603 *
604 * There is a small race between vmem_bt_alloc() returning the page and the
605 * zone lock being acquired to add the page to the zone. For WAITOK
606 * allocations we just pause briefly. NOWAIT may experience a transient
607 * failure. To alleviate this we permit a small number of simultaneous
608 * fills to proceed concurrently so NOWAIT is less likely to fail unless
609 * we are really out of KVA.
610 */
611 static void *
612 vmem_bt_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *pflag, int wait)
613 {
614 vmem_addr_t addr;
615
616 *pflag = UMA_SLAB_KMEM;
617
618 /*
619 * Single thread boundary tag allocation so that the address space
620 * and memory are added in one atomic operation.
621 */
622 mtx_lock(&vmem_bt_lock);
623 if (vmem_xalloc(kmem_arena, bytes, 0, 0, 0, VMEM_ADDR_MIN,
624 VMEM_ADDR_MAX, M_NOWAIT | M_NOVM | M_USE_RESERVE | M_BESTFIT,
625 &addr) == 0) {
626 if (kmem_back(kmem_object, addr, bytes,
627 M_NOWAIT | M_USE_RESERVE) == 0) {
628 mtx_unlock(&vmem_bt_lock);
629 return ((void *)addr);
630 }
631 vmem_xfree(kmem_arena, addr, bytes);
632 mtx_unlock(&vmem_bt_lock);
633 /*
634 * Out of memory, not address space. This may not even be
635 * possible due to M_USE_RESERVE page allocation.
636 */
637 if (wait & M_WAITOK)
638 VM_WAIT;
639 return (NULL);
640 }
641 mtx_unlock(&vmem_bt_lock);
642 /*
643 * We're either out of address space or lost a fill race.
644 */
645 if (wait & M_WAITOK)
646 pause("btalloc", 1);
647
648 return (NULL);
649 }
650 #endif
651
652 void
653 vmem_startup(void)
654 {
655
656 mtx_init(&vmem_list_lock, "vmem list lock", NULL, MTX_DEF);
657 vmem_bt_zone = uma_zcreate("vmem btag",
658 sizeof(struct vmem_btag), NULL, NULL, NULL, NULL,
659 UMA_ALIGN_PTR, UMA_ZONE_VM);
660 #ifndef UMA_MD_SMALL_ALLOC
661 mtx_init(&vmem_bt_lock, "btag lock", NULL, MTX_DEF);
662 uma_prealloc(vmem_bt_zone, BT_MAXALLOC);
663 /*
664 * Reserve enough tags to allocate new tags. We allow multiple
665 * CPUs to attempt to allocate new tags concurrently to limit
666 * false restarts in UMA.
667 */
668 uma_zone_reserve(vmem_bt_zone, BT_MAXALLOC * (mp_ncpus + 1) / 2);
669 uma_zone_set_allocf(vmem_bt_zone, vmem_bt_alloc);
670 #endif
671 }
672
673 /* ---- rehash */
674
675 static int
676 vmem_rehash(vmem_t *vm, vmem_size_t newhashsize)
677 {
678 bt_t *bt;
679 int i;
680 struct vmem_hashlist *newhashlist;
681 struct vmem_hashlist *oldhashlist;
682 vmem_size_t oldhashsize;
683
684 MPASS(newhashsize > 0);
685
686 newhashlist = malloc(sizeof(struct vmem_hashlist) * newhashsize,
687 M_VMEM, M_NOWAIT);
688 if (newhashlist == NULL)
689 return ENOMEM;
690 for (i = 0; i < newhashsize; i++) {
691 LIST_INIT(&newhashlist[i]);
692 }
693
694 VMEM_LOCK(vm);
695 oldhashlist = vm->vm_hashlist;
696 oldhashsize = vm->vm_hashsize;
697 vm->vm_hashlist = newhashlist;
698 vm->vm_hashsize = newhashsize;
699 if (oldhashlist == NULL) {
700 VMEM_UNLOCK(vm);
701 return 0;
702 }
703 for (i = 0; i < oldhashsize; i++) {
704 while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) {
705 bt_rembusy(vm, bt);
706 bt_insbusy(vm, bt);
707 }
708 }
709 VMEM_UNLOCK(vm);
710
711 if (oldhashlist != vm->vm_hash0) {
712 free(oldhashlist, M_VMEM);
713 }
714
715 return 0;
716 }
717
718 static void
719 vmem_periodic_kick(void *dummy)
720 {
721
722 taskqueue_enqueue(taskqueue_thread, &vmem_periodic_wk);
723 }
724
725 static void
726 vmem_periodic(void *unused, int pending)
727 {
728 vmem_t *vm;
729 vmem_size_t desired;
730 vmem_size_t current;
731
732 mtx_lock(&vmem_list_lock);
733 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
734 #ifdef DIAGNOSTIC
735 /* Convenient time to verify vmem state. */
736 if (enable_vmem_check == 1) {
737 VMEM_LOCK(vm);
738 vmem_check(vm);
739 VMEM_UNLOCK(vm);
740 }
741 #endif
742 desired = 1 << flsl(vm->vm_nbusytag);
743 desired = MIN(MAX(desired, VMEM_HASHSIZE_MIN),
744 VMEM_HASHSIZE_MAX);
745 current = vm->vm_hashsize;
746
747 /* Grow in powers of two. Shrink less aggressively. */
748 if (desired >= current * 2 || desired * 4 <= current)
749 vmem_rehash(vm, desired);
750
751 /*
752 * Periodically wake up threads waiting for resources,
753 * so they could ask for reclamation again.
754 */
755 VMEM_CONDVAR_BROADCAST(vm);
756 }
757 mtx_unlock(&vmem_list_lock);
758
759 callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
760 vmem_periodic_kick, NULL);
761 }
762
763 static void
764 vmem_start_callout(void *unused)
765 {
766
767 TASK_INIT(&vmem_periodic_wk, 0, vmem_periodic, NULL);
768 vmem_periodic_interval = hz * 10;
769 callout_init(&vmem_periodic_ch, 1);
770 callout_reset(&vmem_periodic_ch, vmem_periodic_interval,
771 vmem_periodic_kick, NULL);
772 }
773 SYSINIT(vfs, SI_SUB_CONFIGURE, SI_ORDER_ANY, vmem_start_callout, NULL);
774
775 static void
776 vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int type)
777 {
778 bt_t *btspan;
779 bt_t *btfree;
780
781 MPASS(type == BT_TYPE_SPAN || type == BT_TYPE_SPAN_STATIC);
782 MPASS((size & vm->vm_quantum_mask) == 0);
783
784 btspan = bt_alloc(vm);
785 btspan->bt_type = type;
786 btspan->bt_start = addr;
787 btspan->bt_size = size;
788 bt_insseg_tail(vm, btspan);
789
790 btfree = bt_alloc(vm);
791 btfree->bt_type = BT_TYPE_FREE;
792 btfree->bt_start = addr;
793 btfree->bt_size = size;
794 bt_insseg(vm, btfree, btspan);
795 bt_insfree(vm, btfree);
796
797 vm->vm_size += size;
798 }
799
800 static void
801 vmem_destroy1(vmem_t *vm)
802 {
803 bt_t *bt;
804
805 /*
806 * Drain per-cpu quantum caches.
807 */
808 qc_destroy(vm);
809
810 /*
811 * The vmem should now only contain empty segments.
812 */
813 VMEM_LOCK(vm);
814 MPASS(vm->vm_nbusytag == 0);
815
816 while ((bt = TAILQ_FIRST(&vm->vm_seglist)) != NULL)
817 bt_remseg(vm, bt);
818
819 if (vm->vm_hashlist != NULL && vm->vm_hashlist != vm->vm_hash0)
820 free(vm->vm_hashlist, M_VMEM);
821
822 bt_freetrim(vm, 0);
823
824 VMEM_CONDVAR_DESTROY(vm);
825 VMEM_LOCK_DESTROY(vm);
826 free(vm, M_VMEM);
827 }
828
829 static int
830 vmem_import(vmem_t *vm, vmem_size_t size, vmem_size_t align, int flags)
831 {
832 vmem_addr_t addr;
833 int error;
834
835 if (vm->vm_importfn == NULL)
836 return EINVAL;
837
838 /*
839 * To make sure we get a span that meets the alignment we double it
840 * and add the size to the tail. This slightly overestimates.
841 */
842 if (align != vm->vm_quantum_mask + 1)
843 size = (align * 2) + size;
844 size = roundup(size, vm->vm_import_quantum);
845
846 /*
847 * Hide MAXALLOC tags so we're guaranteed to be able to add this
848 * span and the tag we want to allocate from it.
849 */
850 MPASS(vm->vm_nfreetags >= BT_MAXALLOC);
851 vm->vm_nfreetags -= BT_MAXALLOC;
852 VMEM_UNLOCK(vm);
853 error = (vm->vm_importfn)(vm->vm_arg, size, flags, &addr);
854 VMEM_LOCK(vm);
855 vm->vm_nfreetags += BT_MAXALLOC;
856 if (error)
857 return ENOMEM;
858
859 vmem_add1(vm, addr, size, BT_TYPE_SPAN);
860
861 return 0;
862 }
863
864 /*
865 * vmem_fit: check if a bt can satisfy the given restrictions.
866 *
867 * it's a caller's responsibility to ensure the region is big enough
868 * before calling us.
869 */
870 static int
871 vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align,
872 vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr,
873 vmem_addr_t maxaddr, vmem_addr_t *addrp)
874 {
875 vmem_addr_t start;
876 vmem_addr_t end;
877
878 MPASS(size > 0);
879 MPASS(bt->bt_size >= size); /* caller's responsibility */
880
881 /*
882 * XXX assumption: vmem_addr_t and vmem_size_t are
883 * unsigned integer of the same size.
884 */
885
886 start = bt->bt_start;
887 if (start < minaddr) {
888 start = minaddr;
889 }
890 end = BT_END(bt);
891 if (end > maxaddr)
892 end = maxaddr;
893 if (start > end)
894 return (ENOMEM);
895
896 start = VMEM_ALIGNUP(start - phase, align) + phase;
897 if (start < bt->bt_start)
898 start += align;
899 if (VMEM_CROSS_P(start, start + size - 1, nocross)) {
900 MPASS(align < nocross);
901 start = VMEM_ALIGNUP(start - phase, nocross) + phase;
902 }
903 if (start <= end && end - start >= size - 1) {
904 MPASS((start & (align - 1)) == phase);
905 MPASS(!VMEM_CROSS_P(start, start + size - 1, nocross));
906 MPASS(minaddr <= start);
907 MPASS(maxaddr == 0 || start + size - 1 <= maxaddr);
908 MPASS(bt->bt_start <= start);
909 MPASS(BT_END(bt) - start >= size - 1);
910 *addrp = start;
911
912 return (0);
913 }
914 return (ENOMEM);
915 }
916
917 /*
918 * vmem_clip: Trim the boundary tag edges to the requested start and size.
919 */
920 static void
921 vmem_clip(vmem_t *vm, bt_t *bt, vmem_addr_t start, vmem_size_t size)
922 {
923 bt_t *btnew;
924 bt_t *btprev;
925
926 VMEM_ASSERT_LOCKED(vm);
927 MPASS(bt->bt_type == BT_TYPE_FREE);
928 MPASS(bt->bt_size >= size);
929 bt_remfree(vm, bt);
930 if (bt->bt_start != start) {
931 btprev = bt_alloc(vm);
932 btprev->bt_type = BT_TYPE_FREE;
933 btprev->bt_start = bt->bt_start;
934 btprev->bt_size = start - bt->bt_start;
935 bt->bt_start = start;
936 bt->bt_size -= btprev->bt_size;
937 bt_insfree(vm, btprev);
938 bt_insseg(vm, btprev,
939 TAILQ_PREV(bt, vmem_seglist, bt_seglist));
940 }
941 MPASS(bt->bt_start == start);
942 if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) {
943 /* split */
944 btnew = bt_alloc(vm);
945 btnew->bt_type = BT_TYPE_BUSY;
946 btnew->bt_start = bt->bt_start;
947 btnew->bt_size = size;
948 bt->bt_start = bt->bt_start + size;
949 bt->bt_size -= size;
950 bt_insfree(vm, bt);
951 bt_insseg(vm, btnew,
952 TAILQ_PREV(bt, vmem_seglist, bt_seglist));
953 bt_insbusy(vm, btnew);
954 bt = btnew;
955 } else {
956 bt->bt_type = BT_TYPE_BUSY;
957 bt_insbusy(vm, bt);
958 }
959 MPASS(bt->bt_size >= size);
960 bt->bt_type = BT_TYPE_BUSY;
961 }
962
963 /* ---- vmem API */
964
965 void
966 vmem_set_import(vmem_t *vm, vmem_import_t *importfn,
967 vmem_release_t *releasefn, void *arg, vmem_size_t import_quantum)
968 {
969
970 VMEM_LOCK(vm);
971 vm->vm_importfn = importfn;
972 vm->vm_releasefn = releasefn;
973 vm->vm_arg = arg;
974 vm->vm_import_quantum = import_quantum;
975 VMEM_UNLOCK(vm);
976 }
977
978 void
979 vmem_set_reclaim(vmem_t *vm, vmem_reclaim_t *reclaimfn)
980 {
981
982 VMEM_LOCK(vm);
983 vm->vm_reclaimfn = reclaimfn;
984 VMEM_UNLOCK(vm);
985 }
986
987 /*
988 * vmem_init: Initializes vmem arena.
989 */
990 vmem_t *
991 vmem_init(vmem_t *vm, const char *name, vmem_addr_t base, vmem_size_t size,
992 vmem_size_t quantum, vmem_size_t qcache_max, int flags)
993 {
994 int i;
995
996 MPASS(quantum > 0);
997 MPASS((quantum & (quantum - 1)) == 0);
998
999 bzero(vm, sizeof(*vm));
1000
1001 VMEM_CONDVAR_INIT(vm, name);
1002 VMEM_LOCK_INIT(vm, name);
1003 vm->vm_nfreetags = 0;
1004 LIST_INIT(&vm->vm_freetags);
1005 strlcpy(vm->vm_name, name, sizeof(vm->vm_name));
1006 vm->vm_quantum_mask = quantum - 1;
1007 vm->vm_quantum_shift = flsl(quantum) - 1;
1008 vm->vm_nbusytag = 0;
1009 vm->vm_size = 0;
1010 vm->vm_inuse = 0;
1011 qc_init(vm, qcache_max);
1012
1013 TAILQ_INIT(&vm->vm_seglist);
1014 for (i = 0; i < VMEM_MAXORDER; i++) {
1015 LIST_INIT(&vm->vm_freelist[i]);
1016 }
1017 memset(&vm->vm_hash0, 0, sizeof(vm->vm_hash0));
1018 vm->vm_hashsize = VMEM_HASHSIZE_MIN;
1019 vm->vm_hashlist = vm->vm_hash0;
1020
1021 if (size != 0) {
1022 if (vmem_add(vm, base, size, flags) != 0) {
1023 vmem_destroy1(vm);
1024 return NULL;
1025 }
1026 }
1027
1028 mtx_lock(&vmem_list_lock);
1029 LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist);
1030 mtx_unlock(&vmem_list_lock);
1031
1032 return vm;
1033 }
1034
1035 /*
1036 * vmem_create: create an arena.
1037 */
1038 vmem_t *
1039 vmem_create(const char *name, vmem_addr_t base, vmem_size_t size,
1040 vmem_size_t quantum, vmem_size_t qcache_max, int flags)
1041 {
1042
1043 vmem_t *vm;
1044
1045 vm = malloc(sizeof(*vm), M_VMEM, flags & (M_WAITOK|M_NOWAIT));
1046 if (vm == NULL)
1047 return (NULL);
1048 if (vmem_init(vm, name, base, size, quantum, qcache_max,
1049 flags) == NULL)
1050 return (NULL);
1051 return (vm);
1052 }
1053
1054 void
1055 vmem_destroy(vmem_t *vm)
1056 {
1057
1058 mtx_lock(&vmem_list_lock);
1059 LIST_REMOVE(vm, vm_alllist);
1060 mtx_unlock(&vmem_list_lock);
1061
1062 vmem_destroy1(vm);
1063 }
1064
1065 vmem_size_t
1066 vmem_roundup_size(vmem_t *vm, vmem_size_t size)
1067 {
1068
1069 return (size + vm->vm_quantum_mask) & ~vm->vm_quantum_mask;
1070 }
1071
1072 /*
1073 * vmem_alloc: allocate resource from the arena.
1074 */
1075 int
1076 vmem_alloc(vmem_t *vm, vmem_size_t size, int flags, vmem_addr_t *addrp)
1077 {
1078 const int strat __unused = flags & VMEM_FITMASK;
1079 qcache_t *qc;
1080
1081 flags &= VMEM_FLAGS;
1082 MPASS(size > 0);
1083 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT);
1084 if ((flags & M_NOWAIT) == 0)
1085 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_alloc");
1086
1087 if (size <= vm->vm_qcache_max) {
1088 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift];
1089 *addrp = (vmem_addr_t)uma_zalloc(qc->qc_cache, flags);
1090 if (*addrp == 0)
1091 return (ENOMEM);
1092 return (0);
1093 }
1094
1095 return vmem_xalloc(vm, size, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX,
1096 flags, addrp);
1097 }
1098
1099 int
1100 vmem_xalloc(vmem_t *vm, const vmem_size_t size0, vmem_size_t align,
1101 const vmem_size_t phase, const vmem_size_t nocross,
1102 const vmem_addr_t minaddr, const vmem_addr_t maxaddr, int flags,
1103 vmem_addr_t *addrp)
1104 {
1105 const vmem_size_t size = vmem_roundup_size(vm, size0);
1106 struct vmem_freelist *list;
1107 struct vmem_freelist *first;
1108 struct vmem_freelist *end;
1109 vmem_size_t avail;
1110 bt_t *bt;
1111 int error;
1112 int strat;
1113
1114 flags &= VMEM_FLAGS;
1115 strat = flags & VMEM_FITMASK;
1116 MPASS(size0 > 0);
1117 MPASS(size > 0);
1118 MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT);
1119 MPASS((flags & (M_NOWAIT|M_WAITOK)) != (M_NOWAIT|M_WAITOK));
1120 if ((flags & M_NOWAIT) == 0)
1121 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_xalloc");
1122 MPASS((align & vm->vm_quantum_mask) == 0);
1123 MPASS((align & (align - 1)) == 0);
1124 MPASS((phase & vm->vm_quantum_mask) == 0);
1125 MPASS((nocross & vm->vm_quantum_mask) == 0);
1126 MPASS((nocross & (nocross - 1)) == 0);
1127 MPASS((align == 0 && phase == 0) || phase < align);
1128 MPASS(nocross == 0 || nocross >= size);
1129 MPASS(minaddr <= maxaddr);
1130 MPASS(!VMEM_CROSS_P(phase, phase + size - 1, nocross));
1131
1132 if (align == 0)
1133 align = vm->vm_quantum_mask + 1;
1134
1135 *addrp = 0;
1136 end = &vm->vm_freelist[VMEM_MAXORDER];
1137 /*
1138 * choose a free block from which we allocate.
1139 */
1140 first = bt_freehead_toalloc(vm, size, strat);
1141 VMEM_LOCK(vm);
1142 for (;;) {
1143 /*
1144 * Make sure we have enough tags to complete the
1145 * operation.
1146 */
1147 if (vm->vm_nfreetags < BT_MAXALLOC &&
1148 bt_fill(vm, flags) != 0) {
1149 error = ENOMEM;
1150 break;
1151 }
1152 /*
1153 * Scan freelists looking for a tag that satisfies the
1154 * allocation. If we're doing BESTFIT we may encounter
1155 * sizes below the request. If we're doing FIRSTFIT we
1156 * inspect only the first element from each list.
1157 */
1158 for (list = first; list < end; list++) {
1159 LIST_FOREACH(bt, list, bt_freelist) {
1160 if (bt->bt_size >= size) {
1161 error = vmem_fit(bt, size, align, phase,
1162 nocross, minaddr, maxaddr, addrp);
1163 if (error == 0) {
1164 vmem_clip(vm, bt, *addrp, size);
1165 goto out;
1166 }
1167 }
1168 /* FIRST skips to the next list. */
1169 if (strat == M_FIRSTFIT)
1170 break;
1171 }
1172 }
1173 /*
1174 * Retry if the fast algorithm failed.
1175 */
1176 if (strat == M_FIRSTFIT) {
1177 strat = M_BESTFIT;
1178 first = bt_freehead_toalloc(vm, size, strat);
1179 continue;
1180 }
1181 /*
1182 * XXX it is possible to fail to meet restrictions with the
1183 * imported region. It is up to the user to specify the
1184 * import quantum such that it can satisfy any allocation.
1185 */
1186 if (vmem_import(vm, size, align, flags) == 0)
1187 continue;
1188
1189 /*
1190 * Try to free some space from the quantum cache or reclaim
1191 * functions if available.
1192 */
1193 if (vm->vm_qcache_max != 0 || vm->vm_reclaimfn != NULL) {
1194 avail = vm->vm_size - vm->vm_inuse;
1195 VMEM_UNLOCK(vm);
1196 if (vm->vm_qcache_max != 0)
1197 qc_drain(vm);
1198 if (vm->vm_reclaimfn != NULL)
1199 vm->vm_reclaimfn(vm, flags);
1200 VMEM_LOCK(vm);
1201 /* If we were successful retry even NOWAIT. */
1202 if (vm->vm_size - vm->vm_inuse > avail)
1203 continue;
1204 }
1205 if ((flags & M_NOWAIT) != 0) {
1206 error = ENOMEM;
1207 break;
1208 }
1209 VMEM_CONDVAR_WAIT(vm);
1210 }
1211 out:
1212 VMEM_UNLOCK(vm);
1213 if (error != 0 && (flags & M_NOWAIT) == 0)
1214 panic("failed to allocate waiting allocation\n");
1215
1216 return (error);
1217 }
1218
1219 /*
1220 * vmem_free: free the resource to the arena.
1221 */
1222 void
1223 vmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
1224 {
1225 qcache_t *qc;
1226 MPASS(size > 0);
1227
1228 if (size <= vm->vm_qcache_max) {
1229 qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift];
1230 uma_zfree(qc->qc_cache, (void *)addr);
1231 } else
1232 vmem_xfree(vm, addr, size);
1233 }
1234
1235 void
1236 vmem_xfree(vmem_t *vm, vmem_addr_t addr, vmem_size_t size)
1237 {
1238 bt_t *bt;
1239 bt_t *t;
1240
1241 MPASS(size > 0);
1242
1243 VMEM_LOCK(vm);
1244 bt = bt_lookupbusy(vm, addr);
1245 MPASS(bt != NULL);
1246 MPASS(bt->bt_start == addr);
1247 MPASS(bt->bt_size == vmem_roundup_size(vm, size) ||
1248 bt->bt_size - vmem_roundup_size(vm, size) <= vm->vm_quantum_mask);
1249 MPASS(bt->bt_type == BT_TYPE_BUSY);
1250 bt_rembusy(vm, bt);
1251 bt->bt_type = BT_TYPE_FREE;
1252
1253 /* coalesce */
1254 t = TAILQ_NEXT(bt, bt_seglist);
1255 if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1256 MPASS(BT_END(bt) < t->bt_start); /* YYY */
1257 bt->bt_size += t->bt_size;
1258 bt_remfree(vm, t);
1259 bt_remseg(vm, t);
1260 }
1261 t = TAILQ_PREV(bt, vmem_seglist, bt_seglist);
1262 if (t != NULL && t->bt_type == BT_TYPE_FREE) {
1263 MPASS(BT_END(t) < bt->bt_start); /* YYY */
1264 bt->bt_size += t->bt_size;
1265 bt->bt_start = t->bt_start;
1266 bt_remfree(vm, t);
1267 bt_remseg(vm, t);
1268 }
1269
1270 t = TAILQ_PREV(bt, vmem_seglist, bt_seglist);
1271 MPASS(t != NULL);
1272 MPASS(BT_ISSPAN_P(t) || t->bt_type == BT_TYPE_BUSY);
1273 if (vm->vm_releasefn != NULL && t->bt_type == BT_TYPE_SPAN &&
1274 t->bt_size == bt->bt_size) {
1275 vmem_addr_t spanaddr;
1276 vmem_size_t spansize;
1277
1278 MPASS(t->bt_start == bt->bt_start);
1279 spanaddr = bt->bt_start;
1280 spansize = bt->bt_size;
1281 bt_remseg(vm, bt);
1282 bt_remseg(vm, t);
1283 vm->vm_size -= spansize;
1284 VMEM_CONDVAR_BROADCAST(vm);
1285 bt_freetrim(vm, BT_MAXFREE);
1286 (*vm->vm_releasefn)(vm->vm_arg, spanaddr, spansize);
1287 } else {
1288 bt_insfree(vm, bt);
1289 VMEM_CONDVAR_BROADCAST(vm);
1290 bt_freetrim(vm, BT_MAXFREE);
1291 }
1292 }
1293
1294 /*
1295 * vmem_add:
1296 *
1297 */
1298 int
1299 vmem_add(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int flags)
1300 {
1301 int error;
1302
1303 error = 0;
1304 flags &= VMEM_FLAGS;
1305 VMEM_LOCK(vm);
1306 if (vm->vm_nfreetags >= BT_MAXALLOC || bt_fill(vm, flags) == 0)
1307 vmem_add1(vm, addr, size, BT_TYPE_SPAN_STATIC);
1308 else
1309 error = ENOMEM;
1310 VMEM_UNLOCK(vm);
1311
1312 return (error);
1313 }
1314
1315 /*
1316 * vmem_size: information about arenas size
1317 */
1318 vmem_size_t
1319 vmem_size(vmem_t *vm, int typemask)
1320 {
1321 int i;
1322
1323 switch (typemask) {
1324 case VMEM_ALLOC:
1325 return vm->vm_inuse;
1326 case VMEM_FREE:
1327 return vm->vm_size - vm->vm_inuse;
1328 case VMEM_FREE|VMEM_ALLOC:
1329 return vm->vm_size;
1330 case VMEM_MAXFREE:
1331 VMEM_LOCK(vm);
1332 for (i = VMEM_MAXORDER - 1; i >= 0; i--) {
1333 if (LIST_EMPTY(&vm->vm_freelist[i]))
1334 continue;
1335 VMEM_UNLOCK(vm);
1336 return ((vmem_size_t)ORDER2SIZE(i) <<
1337 vm->vm_quantum_shift);
1338 }
1339 VMEM_UNLOCK(vm);
1340 return (0);
1341 default:
1342 panic("vmem_size");
1343 }
1344 }
1345
1346 /* ---- debug */
1347
1348 #if defined(DDB) || defined(DIAGNOSTIC)
1349
1350 static void bt_dump(const bt_t *, int (*)(const char *, ...)
1351 __printflike(1, 2));
1352
1353 static const char *
1354 bt_type_string(int type)
1355 {
1356
1357 switch (type) {
1358 case BT_TYPE_BUSY:
1359 return "busy";
1360 case BT_TYPE_FREE:
1361 return "free";
1362 case BT_TYPE_SPAN:
1363 return "span";
1364 case BT_TYPE_SPAN_STATIC:
1365 return "static span";
1366 default:
1367 break;
1368 }
1369 return "BOGUS";
1370 }
1371
1372 static void
1373 bt_dump(const bt_t *bt, int (*pr)(const char *, ...))
1374 {
1375
1376 (*pr)("\t%p: %jx %jx, %d(%s)\n",
1377 bt, (intmax_t)bt->bt_start, (intmax_t)bt->bt_size,
1378 bt->bt_type, bt_type_string(bt->bt_type));
1379 }
1380
1381 static void
1382 vmem_dump(const vmem_t *vm , int (*pr)(const char *, ...) __printflike(1, 2))
1383 {
1384 const bt_t *bt;
1385 int i;
1386
1387 (*pr)("vmem %p '%s'\n", vm, vm->vm_name);
1388 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1389 bt_dump(bt, pr);
1390 }
1391
1392 for (i = 0; i < VMEM_MAXORDER; i++) {
1393 const struct vmem_freelist *fl = &vm->vm_freelist[i];
1394
1395 if (LIST_EMPTY(fl)) {
1396 continue;
1397 }
1398
1399 (*pr)("freelist[%d]\n", i);
1400 LIST_FOREACH(bt, fl, bt_freelist) {
1401 bt_dump(bt, pr);
1402 }
1403 }
1404 }
1405
1406 #endif /* defined(DDB) || defined(DIAGNOSTIC) */
1407
1408 #if defined(DDB)
1409 #include <ddb/ddb.h>
1410
1411 static bt_t *
1412 vmem_whatis_lookup(vmem_t *vm, vmem_addr_t addr)
1413 {
1414 bt_t *bt;
1415
1416 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1417 if (BT_ISSPAN_P(bt)) {
1418 continue;
1419 }
1420 if (bt->bt_start <= addr && addr <= BT_END(bt)) {
1421 return bt;
1422 }
1423 }
1424
1425 return NULL;
1426 }
1427
1428 void
1429 vmem_whatis(vmem_addr_t addr, int (*pr)(const char *, ...))
1430 {
1431 vmem_t *vm;
1432
1433 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1434 bt_t *bt;
1435
1436 bt = vmem_whatis_lookup(vm, addr);
1437 if (bt == NULL) {
1438 continue;
1439 }
1440 (*pr)("%p is %p+%zu in VMEM '%s' (%s)\n",
1441 (void *)addr, (void *)bt->bt_start,
1442 (vmem_size_t)(addr - bt->bt_start), vm->vm_name,
1443 (bt->bt_type == BT_TYPE_BUSY) ? "allocated" : "free");
1444 }
1445 }
1446
1447 void
1448 vmem_printall(const char *modif, int (*pr)(const char *, ...))
1449 {
1450 const vmem_t *vm;
1451
1452 LIST_FOREACH(vm, &vmem_list, vm_alllist) {
1453 vmem_dump(vm, pr);
1454 }
1455 }
1456
1457 void
1458 vmem_print(vmem_addr_t addr, const char *modif, int (*pr)(const char *, ...))
1459 {
1460 const vmem_t *vm = (const void *)addr;
1461
1462 vmem_dump(vm, pr);
1463 }
1464
1465 DB_SHOW_COMMAND(vmemdump, vmemdump)
1466 {
1467
1468 if (!have_addr) {
1469 db_printf("usage: show vmemdump <addr>\n");
1470 return;
1471 }
1472
1473 vmem_dump((const vmem_t *)addr, db_printf);
1474 }
1475
1476 DB_SHOW_ALL_COMMAND(vmemdump, vmemdumpall)
1477 {
1478 const vmem_t *vm;
1479
1480 LIST_FOREACH(vm, &vmem_list, vm_alllist)
1481 vmem_dump(vm, db_printf);
1482 }
1483
1484 DB_SHOW_COMMAND(vmem, vmem_summ)
1485 {
1486 const vmem_t *vm = (const void *)addr;
1487 const bt_t *bt;
1488 size_t ft[VMEM_MAXORDER], ut[VMEM_MAXORDER];
1489 size_t fs[VMEM_MAXORDER], us[VMEM_MAXORDER];
1490 int ord;
1491
1492 if (!have_addr) {
1493 db_printf("usage: show vmem <addr>\n");
1494 return;
1495 }
1496
1497 db_printf("vmem %p '%s'\n", vm, vm->vm_name);
1498 db_printf("\tquantum:\t%zu\n", vm->vm_quantum_mask + 1);
1499 db_printf("\tsize:\t%zu\n", vm->vm_size);
1500 db_printf("\tinuse:\t%zu\n", vm->vm_inuse);
1501 db_printf("\tfree:\t%zu\n", vm->vm_size - vm->vm_inuse);
1502 db_printf("\tbusy tags:\t%d\n", vm->vm_nbusytag);
1503 db_printf("\tfree tags:\t%d\n", vm->vm_nfreetags);
1504
1505 memset(&ft, 0, sizeof(ft));
1506 memset(&ut, 0, sizeof(ut));
1507 memset(&fs, 0, sizeof(fs));
1508 memset(&us, 0, sizeof(us));
1509 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1510 ord = SIZE2ORDER(bt->bt_size >> vm->vm_quantum_shift);
1511 if (bt->bt_type == BT_TYPE_BUSY) {
1512 ut[ord]++;
1513 us[ord] += bt->bt_size;
1514 } else if (bt->bt_type == BT_TYPE_FREE) {
1515 ft[ord]++;
1516 fs[ord] += bt->bt_size;
1517 }
1518 }
1519 db_printf("\t\t\tinuse\tsize\t\tfree\tsize\n");
1520 for (ord = 0; ord < VMEM_MAXORDER; ord++) {
1521 if (ut[ord] == 0 && ft[ord] == 0)
1522 continue;
1523 db_printf("\t%-15zu %zu\t%-15zu %zu\t%-16zu\n",
1524 ORDER2SIZE(ord) << vm->vm_quantum_shift,
1525 ut[ord], us[ord], ft[ord], fs[ord]);
1526 }
1527 }
1528
1529 DB_SHOW_ALL_COMMAND(vmem, vmem_summall)
1530 {
1531 const vmem_t *vm;
1532
1533 LIST_FOREACH(vm, &vmem_list, vm_alllist)
1534 vmem_summ((db_expr_t)vm, TRUE, count, modif);
1535 }
1536 #endif /* defined(DDB) */
1537
1538 #define vmem_printf printf
1539
1540 #if defined(DIAGNOSTIC)
1541
1542 static bool
1543 vmem_check_sanity(vmem_t *vm)
1544 {
1545 const bt_t *bt, *bt2;
1546
1547 MPASS(vm != NULL);
1548
1549 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1550 if (bt->bt_start > BT_END(bt)) {
1551 printf("corrupted tag\n");
1552 bt_dump(bt, vmem_printf);
1553 return false;
1554 }
1555 }
1556 TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) {
1557 TAILQ_FOREACH(bt2, &vm->vm_seglist, bt_seglist) {
1558 if (bt == bt2) {
1559 continue;
1560 }
1561 if (BT_ISSPAN_P(bt) != BT_ISSPAN_P(bt2)) {
1562 continue;
1563 }
1564 if (bt->bt_start <= BT_END(bt2) &&
1565 bt2->bt_start <= BT_END(bt)) {
1566 printf("overwrapped tags\n");
1567 bt_dump(bt, vmem_printf);
1568 bt_dump(bt2, vmem_printf);
1569 return false;
1570 }
1571 }
1572 }
1573
1574 return true;
1575 }
1576
1577 static void
1578 vmem_check(vmem_t *vm)
1579 {
1580
1581 if (!vmem_check_sanity(vm)) {
1582 panic("insanity vmem %p", vm);
1583 }
1584 }
1585
1586 #endif /* defined(DIAGNOSTIC) */
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