1 /* $NetBSD: kern_malloc.c,v 1.89 2003/10/30 01:58:18 simonb Exp $ */
2
3 /*
4 * Copyright (c) 1987, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)kern_malloc.c 8.4 (Berkeley) 5/20/95
32 */
33
34 /*
35 * Copyright (c) 1996 Christopher G. Demetriou. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. All advertising materials mentioning features or use of this software
46 * must display the following acknowledgement:
47 * This product includes software developed by the University of
48 * California, Berkeley and its contributors.
49 * 4. Neither the name of the University nor the names of its contributors
50 * may be used to endorse or promote products derived from this software
51 * without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 * @(#)kern_malloc.c 8.4 (Berkeley) 5/20/95
66 */
67
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "$NetBSD: kern_malloc.c,v 1.89 2003/10/30 01:58:18 simonb Exp $");
70
71 #include "opt_lockdebug.h"
72
73 #include <sys/param.h>
74 #include <sys/proc.h>
75 #include <sys/kernel.h>
76 #include <sys/malloc.h>
77 #include <sys/systm.h>
78
79 #include <uvm/uvm_extern.h>
80
81 static struct vm_map kmem_map_store;
82 struct vm_map *kmem_map = NULL;
83
84 #include "opt_kmempages.h"
85
86 #ifdef NKMEMCLUSTERS
87 #error NKMEMCLUSTERS is obsolete; remove it from your kernel config file and use NKMEMPAGES instead or let the kernel auto-size
88 #endif
89
90 /*
91 * Default number of pages in kmem_map. We attempt to calculate this
92 * at run-time, but allow it to be either patched or set in the kernel
93 * config file.
94 */
95 #ifndef NKMEMPAGES
96 #define NKMEMPAGES 0
97 #endif
98 int nkmempages = NKMEMPAGES;
99
100 /*
101 * Defaults for lower- and upper-bounds for the kmem_map page count.
102 * Can be overridden by kernel config options.
103 */
104 #ifndef NKMEMPAGES_MIN
105 #define NKMEMPAGES_MIN NKMEMPAGES_MIN_DEFAULT
106 #endif
107
108 #ifndef NKMEMPAGES_MAX
109 #define NKMEMPAGES_MAX NKMEMPAGES_MAX_DEFAULT
110 #endif
111
112 #include "opt_kmemstats.h"
113 #include "opt_malloclog.h"
114 #include "opt_malloc_debug.h"
115
116 struct kmembuckets bucket[MINBUCKET + 16];
117 struct kmemusage *kmemusage;
118 char *kmembase, *kmemlimit;
119
120 struct malloc_type *kmemstatistics;
121
122 #ifdef MALLOCLOG
123 #ifndef MALLOCLOGSIZE
124 #define MALLOCLOGSIZE 100000
125 #endif
126
127 struct malloclog {
128 void *addr;
129 long size;
130 struct malloc_type *type;
131 int action;
132 const char *file;
133 long line;
134 } malloclog[MALLOCLOGSIZE];
135
136 long malloclogptr;
137
138 static void
139 domlog(void *a, long size, struct malloc_type *type, int action,
140 const char *file, long line)
141 {
142
143 malloclog[malloclogptr].addr = a;
144 malloclog[malloclogptr].size = size;
145 malloclog[malloclogptr].type = type;
146 malloclog[malloclogptr].action = action;
147 malloclog[malloclogptr].file = file;
148 malloclog[malloclogptr].line = line;
149 malloclogptr++;
150 if (malloclogptr >= MALLOCLOGSIZE)
151 malloclogptr = 0;
152 }
153
154 static void
155 hitmlog(void *a)
156 {
157 struct malloclog *lp;
158 long l;
159
160 #define PRT do { \
161 lp = &malloclog[l]; \
162 if (lp->addr == a && lp->action) { \
163 printf("malloc log entry %ld:\n", l); \
164 printf("\taddr = %p\n", lp->addr); \
165 printf("\tsize = %ld\n", lp->size); \
166 printf("\ttype = %s\n", lp->type->ks_shortdesc); \
167 printf("\taction = %s\n", lp->action == 1 ? "alloc" : "free"); \
168 printf("\tfile = %s\n", lp->file); \
169 printf("\tline = %ld\n", lp->line); \
170 } \
171 } while (/* CONSTCOND */0)
172
173 for (l = malloclogptr; l < MALLOCLOGSIZE; l++)
174 PRT;
175
176 for (l = 0; l < malloclogptr; l++)
177 PRT;
178 #undef PRT
179 }
180 #endif /* MALLOCLOG */
181
182 #ifdef DIAGNOSTIC
183 /*
184 * This structure provides a set of masks to catch unaligned frees.
185 */
186 const long addrmask[] = { 0,
187 0x00000001, 0x00000003, 0x00000007, 0x0000000f,
188 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
189 0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff,
190 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff,
191 };
192
193 /*
194 * The WEIRD_ADDR is used as known text to copy into free objects so
195 * that modifications after frees can be detected.
196 */
197 #define WEIRD_ADDR ((uint32_t) 0xdeadbeef)
198 #ifdef DEBUG
199 #define MAX_COPY PAGE_SIZE
200 #else
201 #define MAX_COPY 32
202 #endif
203
204 /*
205 * Normally the freelist structure is used only to hold the list pointer
206 * for free objects. However, when running with diagnostics, the first
207 * 8/16 bytes of the structure is unused except for diagnostic information,
208 * and the free list pointer is at offset 8/16 in the structure. Since the
209 * first 8 bytes is the portion of the structure most often modified, this
210 * helps to detect memory reuse problems and avoid free list corruption.
211 */
212 struct freelist {
213 uint32_t spare0;
214 #ifdef _LP64
215 uint32_t spare1; /* explicit padding */
216 #endif
217 struct malloc_type *type;
218 caddr_t next;
219 };
220 #else /* !DIAGNOSTIC */
221 struct freelist {
222 caddr_t next;
223 };
224 #endif /* DIAGNOSTIC */
225
226 /*
227 * The following are standard, build-in malloc types are are not
228 * specific to any one subsystem.
229 */
230 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
231 MALLOC_DEFINE(M_DMAMAP, "DMA map", "bus_dma(9) structures");
232 MALLOC_DEFINE(M_FREE, "free", "should be on free list");
233 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
234 MALLOC_DEFINE(M_SOFTINTR, "softintr", "Softinterrupt structures");
235 MALLOC_DEFINE(M_TEMP, "temp", "misc. temporary data buffers");
236
237 /* XXX These should all be elsewhere. */
238 MALLOC_DEFINE(M_RTABLE, "routetbl", "routing tables");
239 MALLOC_DEFINE(M_FTABLE, "fragtbl", "fragment reassembly header");
240 MALLOC_DEFINE(M_UFSMNT, "UFS mount", "UFS mount structure");
241 MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure");
242 MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
243 MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
244 MALLOC_DEFINE(M_MRTABLE, "mrt", "multicast routing tables");
245 MALLOC_DEFINE(M_1394DATA, "1394data", "IEEE 1394 data buffers");
246
247 struct simplelock malloc_slock = SIMPLELOCK_INITIALIZER;
248
249 /*
250 * Allocate a block of memory
251 */
252 #ifdef MALLOCLOG
253 void *
254 _malloc(unsigned long size, struct malloc_type *ksp, int flags,
255 const char *file, long line)
256 #else
257 void *
258 malloc(unsigned long size, struct malloc_type *ksp, int flags)
259 #endif /* MALLOCLOG */
260 {
261 struct kmembuckets *kbp;
262 struct kmemusage *kup;
263 struct freelist *freep;
264 long indx, npg, allocsize;
265 int s;
266 caddr_t va, cp, savedlist;
267 #ifdef DIAGNOSTIC
268 uint32_t *end, *lp;
269 int copysize;
270 #endif
271
272 #ifdef LOCKDEBUG
273 if ((flags & M_NOWAIT) == 0)
274 simple_lock_only_held(NULL, "malloc");
275 #endif
276 #ifdef MALLOC_DEBUG
277 if (debug_malloc(size, ksp, flags, (void *) &va))
278 return ((void *) va);
279 #endif
280 indx = BUCKETINDX(size);
281 kbp = &bucket[indx];
282 s = splvm();
283 simple_lock(&malloc_slock);
284 #ifdef KMEMSTATS
285 while (ksp->ks_memuse >= ksp->ks_limit) {
286 if (flags & M_NOWAIT) {
287 simple_unlock(&malloc_slock);
288 splx(s);
289 return ((void *) NULL);
290 }
291 if (ksp->ks_limblocks < 65535)
292 ksp->ks_limblocks++;
293 ltsleep((caddr_t)ksp, PSWP+2, ksp->ks_shortdesc, 0,
294 &malloc_slock);
295 }
296 ksp->ks_size |= 1 << indx;
297 #endif
298 #ifdef DIAGNOSTIC
299 copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY;
300 #endif
301 if (kbp->kb_next == NULL) {
302 kbp->kb_last = NULL;
303 if (size > MAXALLOCSAVE)
304 allocsize = round_page(size);
305 else
306 allocsize = 1 << indx;
307 npg = btoc(allocsize);
308 simple_unlock(&malloc_slock);
309 va = (caddr_t) uvm_km_kmemalloc(kmem_map, NULL,
310 (vsize_t)ctob(npg),
311 ((flags & M_NOWAIT) ? UVM_KMF_NOWAIT : 0) |
312 ((flags & M_CANFAIL) ? UVM_KMF_CANFAIL : 0));
313 if (__predict_false(va == NULL)) {
314 /*
315 * Kmem_malloc() can return NULL, even if it can
316 * wait, if there is no map space avaiable, because
317 * it can't fix that problem. Neither can we,
318 * right now. (We should release pages which
319 * are completely free and which are in buckets
320 * with too many free elements.)
321 */
322 if ((flags & (M_NOWAIT|M_CANFAIL)) == 0)
323 panic("malloc: out of space in kmem_map");
324 splx(s);
325 return (NULL);
326 }
327 simple_lock(&malloc_slock);
328 #ifdef KMEMSTATS
329 kbp->kb_total += kbp->kb_elmpercl;
330 #endif
331 kup = btokup(va);
332 kup->ku_indx = indx;
333 if (allocsize > MAXALLOCSAVE) {
334 if (npg > 65535)
335 panic("malloc: allocation too large");
336 kup->ku_pagecnt = npg;
337 #ifdef KMEMSTATS
338 ksp->ks_memuse += allocsize;
339 #endif
340 goto out;
341 }
342 #ifdef KMEMSTATS
343 kup->ku_freecnt = kbp->kb_elmpercl;
344 kbp->kb_totalfree += kbp->kb_elmpercl;
345 #endif
346 /*
347 * Just in case we blocked while allocating memory,
348 * and someone else also allocated memory for this
349 * bucket, don't assume the list is still empty.
350 */
351 savedlist = kbp->kb_next;
352 kbp->kb_next = cp = va + (npg << PAGE_SHIFT) - allocsize;
353 for (;;) {
354 freep = (struct freelist *)cp;
355 #ifdef DIAGNOSTIC
356 /*
357 * Copy in known text to detect modification
358 * after freeing.
359 */
360 end = (uint32_t *)&cp[copysize];
361 for (lp = (uint32_t *)cp; lp < end; lp++)
362 *lp = WEIRD_ADDR;
363 freep->type = M_FREE;
364 #endif /* DIAGNOSTIC */
365 if (cp <= va)
366 break;
367 cp -= allocsize;
368 freep->next = cp;
369 }
370 freep->next = savedlist;
371 if (kbp->kb_last == NULL)
372 kbp->kb_last = (caddr_t)freep;
373 }
374 va = kbp->kb_next;
375 kbp->kb_next = ((struct freelist *)va)->next;
376 #ifdef DIAGNOSTIC
377 freep = (struct freelist *)va;
378 /* XXX potential to get garbage pointer here. */
379 if (kbp->kb_next) {
380 int rv;
381 vaddr_t addr = (vaddr_t)kbp->kb_next;
382
383 vm_map_lock(kmem_map);
384 rv = uvm_map_checkprot(kmem_map, addr,
385 addr + sizeof(struct freelist), VM_PROT_WRITE);
386 vm_map_unlock(kmem_map);
387
388 if (__predict_false(rv == 0)) {
389 printf("Data modified on freelist: "
390 "word %ld of object %p size %ld previous type %s "
391 "(invalid addr %p)\n",
392 (long)((int32_t *)&kbp->kb_next - (int32_t *)kbp),
393 va, size, "foo", kbp->kb_next);
394 #ifdef MALLOCLOG
395 hitmlog(va);
396 #endif
397 kbp->kb_next = NULL;
398 }
399 }
400
401 /* Fill the fields that we've used with WEIRD_ADDR */
402 #ifdef _LP64
403 freep->type = (struct malloc_type *)
404 (WEIRD_ADDR | (((u_long) WEIRD_ADDR) << 32));
405 #else
406 freep->type = (struct malloc_type *) WEIRD_ADDR;
407 #endif
408 end = (uint32_t *)&freep->next +
409 (sizeof(freep->next) / sizeof(int32_t));
410 for (lp = (uint32_t *)&freep->next; lp < end; lp++)
411 *lp = WEIRD_ADDR;
412
413 /* and check that the data hasn't been modified. */
414 end = (uint32_t *)&va[copysize];
415 for (lp = (uint32_t *)va; lp < end; lp++) {
416 if (__predict_true(*lp == WEIRD_ADDR))
417 continue;
418 printf("Data modified on freelist: "
419 "word %ld of object %p size %ld previous type %s "
420 "(0x%x != 0x%x)\n",
421 (long)(lp - (uint32_t *)va), va, size,
422 "bar", *lp, WEIRD_ADDR);
423 #ifdef MALLOCLOG
424 hitmlog(va);
425 #endif
426 break;
427 }
428
429 freep->spare0 = 0;
430 #endif /* DIAGNOSTIC */
431 #ifdef KMEMSTATS
432 kup = btokup(va);
433 if (kup->ku_indx != indx)
434 panic("malloc: wrong bucket");
435 if (kup->ku_freecnt == 0)
436 panic("malloc: lost data");
437 kup->ku_freecnt--;
438 kbp->kb_totalfree--;
439 ksp->ks_memuse += 1 << indx;
440 out:
441 kbp->kb_calls++;
442 ksp->ks_inuse++;
443 ksp->ks_calls++;
444 if (ksp->ks_memuse > ksp->ks_maxused)
445 ksp->ks_maxused = ksp->ks_memuse;
446 #else
447 out:
448 #endif
449 #ifdef MALLOCLOG
450 domlog(va, size, ksp, 1, file, line);
451 #endif
452 simple_unlock(&malloc_slock);
453 splx(s);
454 if ((flags & M_ZERO) != 0)
455 memset(va, 0, size);
456 return ((void *) va);
457 }
458
459 /*
460 * Free a block of memory allocated by malloc.
461 */
462 #ifdef MALLOCLOG
463 void
464 _free(void *addr, struct malloc_type *ksp, const char *file, long line)
465 #else
466 void
467 free(void *addr, struct malloc_type *ksp)
468 #endif /* MALLOCLOG */
469 {
470 struct kmembuckets *kbp;
471 struct kmemusage *kup;
472 struct freelist *freep;
473 long size;
474 int s;
475 #ifdef DIAGNOSTIC
476 caddr_t cp;
477 int32_t *end, *lp;
478 long alloc, copysize;
479 #endif
480
481 #ifdef MALLOC_DEBUG
482 if (debug_free(addr, ksp))
483 return;
484 #endif
485
486 #ifdef DIAGNOSTIC
487 /*
488 * Ensure that we're free'ing something that we could
489 * have allocated in the first place. That is, check
490 * to see that the address is within kmem_map.
491 */
492 if (__predict_false((vaddr_t)addr < vm_map_min(kmem_map) ||
493 (vaddr_t)addr >= vm_map_max(kmem_map)))
494 panic("free: addr %p not within kmem_map", addr);
495 #endif
496
497 kup = btokup(addr);
498 size = 1 << kup->ku_indx;
499 kbp = &bucket[kup->ku_indx];
500 s = splvm();
501 simple_lock(&malloc_slock);
502 #ifdef MALLOCLOG
503 domlog(addr, 0, ksp, 2, file, line);
504 #endif
505 #ifdef DIAGNOSTIC
506 /*
507 * Check for returns of data that do not point to the
508 * beginning of the allocation.
509 */
510 if (size > PAGE_SIZE)
511 alloc = addrmask[BUCKETINDX(PAGE_SIZE)];
512 else
513 alloc = addrmask[kup->ku_indx];
514 if (((u_long)addr & alloc) != 0)
515 panic("free: unaligned addr %p, size %ld, type %s, mask %ld",
516 addr, size, ksp->ks_shortdesc, alloc);
517 #endif /* DIAGNOSTIC */
518 if (size > MAXALLOCSAVE) {
519 uvm_km_free(kmem_map, (vaddr_t)addr, ctob(kup->ku_pagecnt));
520 #ifdef KMEMSTATS
521 size = kup->ku_pagecnt << PGSHIFT;
522 ksp->ks_memuse -= size;
523 kup->ku_indx = 0;
524 kup->ku_pagecnt = 0;
525 if (ksp->ks_memuse + size >= ksp->ks_limit &&
526 ksp->ks_memuse < ksp->ks_limit)
527 wakeup((caddr_t)ksp);
528 #ifdef DIAGNOSTIC
529 if (ksp->ks_inuse == 0)
530 panic("free 1: inuse 0, probable double free");
531 #endif
532 ksp->ks_inuse--;
533 kbp->kb_total -= 1;
534 #endif
535 simple_unlock(&malloc_slock);
536 splx(s);
537 return;
538 }
539 freep = (struct freelist *)addr;
540 #ifdef DIAGNOSTIC
541 /*
542 * Check for multiple frees. Use a quick check to see if
543 * it looks free before laboriously searching the freelist.
544 */
545 if (__predict_false(freep->spare0 == WEIRD_ADDR)) {
546 for (cp = kbp->kb_next; cp;
547 cp = ((struct freelist *)cp)->next) {
548 if (addr != cp)
549 continue;
550 printf("multiply freed item %p\n", addr);
551 #ifdef MALLOCLOG
552 hitmlog(addr);
553 #endif
554 panic("free: duplicated free");
555 }
556 }
557 #ifdef LOCKDEBUG
558 /*
559 * Check if we're freeing a locked simple lock.
560 */
561 simple_lock_freecheck(addr, (char *)addr + size);
562 #endif
563 /*
564 * Copy in known text to detect modification after freeing
565 * and to make it look free. Also, save the type being freed
566 * so we can list likely culprit if modification is detected
567 * when the object is reallocated.
568 */
569 copysize = size < MAX_COPY ? size : MAX_COPY;
570 end = (int32_t *)&((caddr_t)addr)[copysize];
571 for (lp = (int32_t *)addr; lp < end; lp++)
572 *lp = WEIRD_ADDR;
573 freep->type = ksp;
574 #endif /* DIAGNOSTIC */
575 #ifdef KMEMSTATS
576 kup->ku_freecnt++;
577 if (kup->ku_freecnt >= kbp->kb_elmpercl) {
578 if (kup->ku_freecnt > kbp->kb_elmpercl)
579 panic("free: multiple frees");
580 else if (kbp->kb_totalfree > kbp->kb_highwat)
581 kbp->kb_couldfree++;
582 }
583 kbp->kb_totalfree++;
584 ksp->ks_memuse -= size;
585 if (ksp->ks_memuse + size >= ksp->ks_limit &&
586 ksp->ks_memuse < ksp->ks_limit)
587 wakeup((caddr_t)ksp);
588 #ifdef DIAGNOSTIC
589 if (ksp->ks_inuse == 0)
590 panic("free 2: inuse 0, probable double free");
591 #endif
592 ksp->ks_inuse--;
593 #endif
594 if (kbp->kb_next == NULL)
595 kbp->kb_next = addr;
596 else
597 ((struct freelist *)kbp->kb_last)->next = addr;
598 freep->next = NULL;
599 kbp->kb_last = addr;
600 simple_unlock(&malloc_slock);
601 splx(s);
602 }
603
604 /*
605 * Change the size of a block of memory.
606 */
607 void *
608 realloc(void *curaddr, unsigned long newsize, struct malloc_type *ksp,
609 int flags)
610 {
611 struct kmemusage *kup;
612 unsigned long cursize;
613 void *newaddr;
614 #ifdef DIAGNOSTIC
615 long alloc;
616 #endif
617
618 /*
619 * realloc() with a NULL pointer is the same as malloc().
620 */
621 if (curaddr == NULL)
622 return (malloc(newsize, ksp, flags));
623
624 /*
625 * realloc() with zero size is the same as free().
626 */
627 if (newsize == 0) {
628 free(curaddr, ksp);
629 return (NULL);
630 }
631
632 #ifdef LOCKDEBUG
633 if ((flags & M_NOWAIT) == 0)
634 simple_lock_only_held(NULL, "realloc");
635 #endif
636
637 /*
638 * Find out how large the old allocation was (and do some
639 * sanity checking).
640 */
641 kup = btokup(curaddr);
642 cursize = 1 << kup->ku_indx;
643
644 #ifdef DIAGNOSTIC
645 /*
646 * Check for returns of data that do not point to the
647 * beginning of the allocation.
648 */
649 if (cursize > PAGE_SIZE)
650 alloc = addrmask[BUCKETINDX(PAGE_SIZE)];
651 else
652 alloc = addrmask[kup->ku_indx];
653 if (((u_long)curaddr & alloc) != 0)
654 panic("realloc: "
655 "unaligned addr %p, size %ld, type %s, mask %ld\n",
656 curaddr, cursize, ksp->ks_shortdesc, alloc);
657 #endif /* DIAGNOSTIC */
658
659 if (cursize > MAXALLOCSAVE)
660 cursize = ctob(kup->ku_pagecnt);
661
662 /*
663 * If we already actually have as much as they want, we're done.
664 */
665 if (newsize <= cursize)
666 return (curaddr);
667
668 /*
669 * Can't satisfy the allocation with the existing block.
670 * Allocate a new one and copy the data.
671 */
672 newaddr = malloc(newsize, ksp, flags);
673 if (__predict_false(newaddr == NULL)) {
674 /*
675 * malloc() failed, because flags included M_NOWAIT.
676 * Return NULL to indicate that failure. The old
677 * pointer is still valid.
678 */
679 return (NULL);
680 }
681 memcpy(newaddr, curaddr, cursize);
682
683 /*
684 * We were successful: free the old allocation and return
685 * the new one.
686 */
687 free(curaddr, ksp);
688 return (newaddr);
689 }
690
691 /*
692 * Roundup size to the actual allocation size.
693 */
694 unsigned long
695 malloc_roundup(unsigned long size)
696 {
697
698 if (size > MAXALLOCSAVE)
699 return (roundup(size, PAGE_SIZE));
700 else
701 return (1 << BUCKETINDX(size));
702 }
703
704 /*
705 * Add a malloc type to the system.
706 */
707 void
708 malloc_type_attach(struct malloc_type *type)
709 {
710
711 if (nkmempages == 0)
712 panic("malloc_type_attach: nkmempages == 0");
713
714 if (type->ks_magic != M_MAGIC)
715 panic("malloc_type_attach: bad magic");
716
717 #ifdef DIAGNOSTIC
718 {
719 struct malloc_type *ksp;
720 for (ksp = kmemstatistics; ksp != NULL; ksp = ksp->ks_next) {
721 if (ksp == type)
722 panic("malloc_type_attach: already on list");
723 }
724 }
725 #endif
726
727 #ifdef KMEMSTATS
728 if (type->ks_limit == 0)
729 type->ks_limit = ((u_long)nkmempages << PAGE_SHIFT) * 6U / 10U;
730 #else
731 type->ks_limit = 0;
732 #endif
733
734 type->ks_next = kmemstatistics;
735 kmemstatistics = type;
736 }
737
738 /*
739 * Remove a malloc type from the system..
740 */
741 void
742 malloc_type_detach(struct malloc_type *type)
743 {
744 struct malloc_type *ksp;
745
746 #ifdef DIAGNOSTIC
747 if (type->ks_magic != M_MAGIC)
748 panic("malloc_type_detach: bad magic");
749 #endif
750
751 if (type == kmemstatistics)
752 kmemstatistics = type->ks_next;
753 else {
754 for (ksp = kmemstatistics; ksp->ks_next != NULL;
755 ksp = ksp->ks_next) {
756 if (ksp->ks_next == type) {
757 ksp->ks_next = type->ks_next;
758 break;
759 }
760 }
761 #ifdef DIAGNOSTIC
762 if (ksp->ks_next == NULL)
763 panic("malloc_type_detach: not on list");
764 #endif
765 }
766 type->ks_next = NULL;
767 }
768
769 /*
770 * Set the limit on a malloc type.
771 */
772 void
773 malloc_type_setlimit(struct malloc_type *type, u_long limit)
774 {
775 #ifdef KMEMSTATS
776 int s;
777
778 s = splvm();
779 type->ks_limit = limit;
780 splx(s);
781 #endif
782 }
783
784 /*
785 * Compute the number of pages that kmem_map will map, that is,
786 * the size of the kernel malloc arena.
787 */
788 void
789 kmeminit_nkmempages(void)
790 {
791 int npages;
792
793 if (nkmempages != 0) {
794 /*
795 * It's already been set (by us being here before, or
796 * by patching or kernel config options), bail out now.
797 */
798 return;
799 }
800
801 /*
802 * We use the following (simple) formula:
803 *
804 * - Starting point is physical memory / 4.
805 *
806 * - Clamp it down to NKMEMPAGES_MAX.
807 *
808 * - Round it up to NKMEMPAGES_MIN.
809 */
810 npages = physmem / 4;
811
812 if (npages > NKMEMPAGES_MAX)
813 npages = NKMEMPAGES_MAX;
814
815 if (npages < NKMEMPAGES_MIN)
816 npages = NKMEMPAGES_MIN;
817
818 nkmempages = npages;
819 }
820
821 /*
822 * Initialize the kernel memory allocator
823 */
824 void
825 kmeminit(void)
826 {
827 __link_set_decl(malloc_types, struct malloc_type);
828 struct malloc_type * const *ksp;
829 vaddr_t kmb, kml;
830 #ifdef KMEMSTATS
831 long indx;
832 #endif
833
834 #if ((MAXALLOCSAVE & (MAXALLOCSAVE - 1)) != 0)
835 ERROR!_kmeminit:_MAXALLOCSAVE_not_power_of_2
836 #endif
837 #if (MAXALLOCSAVE > MINALLOCSIZE * 32768)
838 ERROR!_kmeminit:_MAXALLOCSAVE_too_big
839 #endif
840 #if (MAXALLOCSAVE < NBPG)
841 ERROR!_kmeminit:_MAXALLOCSAVE_too_small
842 #endif
843
844 if (sizeof(struct freelist) > (1 << MINBUCKET))
845 panic("minbucket too small/struct freelist too big");
846
847 /*
848 * Compute the number of kmem_map pages, if we have not
849 * done so already.
850 */
851 kmeminit_nkmempages();
852
853 kmemusage = (struct kmemusage *) uvm_km_zalloc(kernel_map,
854 (vsize_t)(nkmempages * sizeof(struct kmemusage)));
855 kmb = 0;
856 kmem_map = uvm_km_suballoc(kernel_map, &kmb,
857 &kml, (vsize_t)(nkmempages << PAGE_SHIFT),
858 VM_MAP_INTRSAFE, FALSE, &kmem_map_store);
859 kmembase = (char *)kmb;
860 kmemlimit = (char *)kml;
861 #ifdef KMEMSTATS
862 for (indx = 0; indx < MINBUCKET + 16; indx++) {
863 if (1 << indx >= PAGE_SIZE)
864 bucket[indx].kb_elmpercl = 1;
865 else
866 bucket[indx].kb_elmpercl = PAGE_SIZE / (1 << indx);
867 bucket[indx].kb_highwat = 5 * bucket[indx].kb_elmpercl;
868 }
869 #endif
870
871 /* Attach all of the statically-linked malloc types. */
872 __link_set_foreach(ksp, malloc_types)
873 malloc_type_attach(*ksp);
874
875 #ifdef MALLOC_DEBUG
876 debug_malloc_init();
877 #endif
878 }
879
880 #ifdef DDB
881 #include <ddb/db_output.h>
882
883 /*
884 * Dump kmem statistics from ddb.
885 *
886 * usage: call dump_kmemstats
887 */
888 void dump_kmemstats(void);
889
890 void
891 dump_kmemstats(void)
892 {
893 #ifdef KMEMSTATS
894 struct malloc_type *ksp;
895
896 for (ksp = kmemstatistics; ksp != NULL; ksp = ksp->ks_next) {
897 if (ksp->ks_memuse == 0)
898 continue;
899 db_printf("%s%.*s %ld\n", ksp->ks_shortdesc,
900 (int)(20 - strlen(ksp->ks_shortdesc)),
901 " ",
902 ksp->ks_memuse);
903 }
904 #else
905 db_printf("Kmem stats are not being collected.\n");
906 #endif /* KMEMSTATS */
907 }
908 #endif /* DDB */
909
910
911 #if 0
912 /*
913 * Diagnostic messages about "Data modified on
914 * freelist" indicate a memory corruption, but
915 * they do not help tracking it down.
916 * This function can be called at various places
917 * to sanity check malloc's freelist and discover
918 * where does the corruption take place.
919 */
920 int
921 freelist_sanitycheck(void) {
922 int i,j;
923 struct kmembuckets *kbp;
924 struct freelist *freep;
925 int rv = 0;
926
927 for (i = MINBUCKET; i <= MINBUCKET + 15; i++) {
928 kbp = &bucket[i];
929 freep = (struct freelist *)kbp->kb_next;
930 j = 0;
931 while(freep) {
932 vm_map_lock(kmem_map);
933 rv = uvm_map_checkprot(kmem_map, (vaddr_t)freep,
934 (vaddr_t)freep + sizeof(struct freelist),
935 VM_PROT_WRITE);
936 vm_map_unlock(kmem_map);
937
938 if ((rv == 0) || (*(int *)freep != WEIRD_ADDR)) {
939 printf("bucket %i, chunck %d at %p modified\n",
940 i, j, freep);
941 return 1;
942 }
943 freep = (struct freelist *)freep->next;
944 j++;
945 }
946 }
947
948 return 0;
949 }
950 #endif
Cache object: 42148b8d845df741d82b06e344966357
|