diff options
Diffstat (limited to 'src/lib/libc/stdlib/malloc.c')
-rw-r--r-- | src/lib/libc/stdlib/malloc.c | 1592 |
1 files changed, 1238 insertions, 354 deletions
diff --git a/src/lib/libc/stdlib/malloc.c b/src/lib/libc/stdlib/malloc.c index 3c57fad024..4e90ce402e 100644 --- a/src/lib/libc/stdlib/malloc.c +++ b/src/lib/libc/stdlib/malloc.c | |||
@@ -1,421 +1,1305 @@ | |||
1 | /* | 1 | /* |
2 | * Copyright (c) 1983 Regents of the University of California. | 2 | * ---------------------------------------------------------------------------- |
3 | * All rights reserved. | 3 | * "THE BEER-WARE LICENSE" (Revision 42): |
4 | * | 4 | * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you |
5 | * Redistribution and use in source and binary forms, with or without | 5 | * can do whatever you want with this stuff. If we meet some day, and you think |
6 | * modification, are permitted provided that the following conditions | 6 | * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp |
7 | * are met: | 7 | * ---------------------------------------------------------------------------- |
8 | * 1. Redistributions of source code must retain the above copyright | ||
9 | * notice, this list of conditions and the following disclaimer. | ||
10 | * 2. Redistributions in binary form must reproduce the above copyright | ||
11 | * notice, this list of conditions and the following disclaimer in the | ||
12 | * documentation and/or other materials provided with the distribution. | ||
13 | * 3. All advertising materials mentioning features or use of this software | ||
14 | * must display the following acknowledgement: | ||
15 | * This product includes software developed by the University of | ||
16 | * California, Berkeley and its contributors. | ||
17 | * 4. Neither the name of the University nor the names of its contributors | ||
18 | * may be used to endorse or promote products derived from this software | ||
19 | * without specific prior written permission. | ||
20 | * | ||
21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | ||
22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | ||
25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | ||
26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | ||
27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | ||
29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | ||
30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | ||
31 | * SUCH DAMAGE. | ||
32 | */ | 8 | */ |
33 | 9 | ||
34 | #if defined(LIBC_SCCS) && !defined(lint) | 10 | #if defined(LIBC_SCCS) && !defined(lint) |
35 | /*static char *sccsid = "from: @(#)malloc.c 5.11 (Berkeley) 2/23/91";*/ | 11 | static char rcsid[] = "$OpenBSD: malloc.c,v 1.48 2002/05/27 03:13:23 deraadt Exp $"; |
36 | static char *rcsid = "$Id: malloc.c,v 1.1.1.1 1995/10/18 08:42:18 deraadt Exp $"; | ||
37 | #endif /* LIBC_SCCS and not lint */ | 12 | #endif /* LIBC_SCCS and not lint */ |
38 | 13 | ||
39 | /* | 14 | /* |
40 | * malloc.c (Caltech) 2/21/82 | 15 | * Defining MALLOC_EXTRA_SANITY will enable extra checks which are |
41 | * Chris Kingsley, kingsley@cit-20. | 16 | * related to internal conditions and consistency in malloc.c. This has |
42 | * | 17 | * a noticeable runtime performance hit, and generally will not do you |
43 | * This is a very fast storage allocator. It allocates blocks of a small | 18 | * any good unless you fiddle with the internals of malloc or want |
44 | * number of different sizes, and keeps free lists of each size. Blocks that | 19 | * to catch random pointer corruption as early as possible. |
45 | * don't exactly fit are passed up to the next larger size. In this | 20 | */ |
46 | * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long. | 21 | #ifndef MALLOC_EXTRA_SANITY |
47 | * This is designed for use in a virtual memory environment. | 22 | #undef MALLOC_EXTRA_SANITY |
23 | #endif | ||
24 | |||
25 | /* | ||
26 | * Defining MALLOC_STATS will enable you to call malloc_dump() and set | ||
27 | * the [dD] options in the MALLOC_OPTIONS environment variable. | ||
28 | * It has no run-time performance hit, but does pull in stdio... | ||
29 | */ | ||
30 | #ifndef MALLOC_STATS | ||
31 | #undef MALLOC_STATS | ||
32 | #endif | ||
33 | |||
34 | /* | ||
35 | * What to use for Junk. This is the byte value we use to fill with | ||
36 | * when the 'J' option is enabled. | ||
48 | */ | 37 | */ |
38 | #define SOME_JUNK 0xd0 /* as in "Duh" :-) */ | ||
49 | 39 | ||
50 | #include <sys/types.h> | 40 | #include <sys/types.h> |
41 | #include <sys/param.h> | ||
42 | #include <sys/mman.h> | ||
43 | #include <sys/uio.h> | ||
44 | #include <stdio.h> | ||
51 | #include <stdlib.h> | 45 | #include <stdlib.h> |
52 | #include <string.h> | 46 | #include <string.h> |
53 | #include <unistd.h> | 47 | #include <unistd.h> |
48 | #include <fcntl.h> | ||
49 | #include <errno.h> | ||
50 | |||
51 | /* | ||
52 | * The basic parameters you can tweak. | ||
53 | * | ||
54 | * malloc_pageshift pagesize = 1 << malloc_pageshift | ||
55 | * It's probably best if this is the native | ||
56 | * page size, but it shouldn't have to be. | ||
57 | * | ||
58 | * malloc_minsize minimum size of an allocation in bytes. | ||
59 | * If this is too small it's too much work | ||
60 | * to manage them. This is also the smallest | ||
61 | * unit of alignment used for the storage | ||
62 | * returned by malloc/realloc. | ||
63 | * | ||
64 | */ | ||
65 | |||
66 | #if defined(__OpenBSD__) && defined(__sparc__) | ||
67 | # define malloc_pageshift 13U | ||
68 | #endif /* __OpenBSD__ */ | ||
69 | |||
70 | #ifdef _THREAD_SAFE | ||
71 | # include "thread_private.h" | ||
72 | # if 0 | ||
73 | /* kernel threads */ | ||
74 | # include <pthread.h> | ||
75 | static pthread_mutex_t malloc_lock; | ||
76 | # define THREAD_LOCK() pthread_mutex_lock(&malloc_lock) | ||
77 | # define THREAD_UNLOCK() pthread_mutex_unlock(&malloc_lock) | ||
78 | # define THREAD_LOCK_INIT() pthread_mutex_init(&malloc_lock, 0); | ||
79 | # else | ||
80 | /* user threads */ | ||
81 | # include "spinlock.h" | ||
82 | static spinlock_t malloc_lock = _SPINLOCK_INITIALIZER; | ||
83 | # define THREAD_LOCK() if (__isthreaded) _SPINLOCK(&malloc_lock) | ||
84 | # define THREAD_UNLOCK() if (__isthreaded) _SPINUNLOCK(&malloc_lock) | ||
85 | # define THREAD_LOCK_INIT() | ||
86 | /* | ||
87 | * Malloc can't use the wrapped write() if it fails very early, so | ||
88 | * we use the unwrapped syscall _thread_sys_write() | ||
89 | */ | ||
90 | # define write _thread_sys_write | ||
91 | ssize_t write(int, const void *, size_t); | ||
92 | # undef malloc | ||
93 | # undef realloc | ||
94 | # undef free | ||
95 | # endif | ||
96 | #else | ||
97 | /* no threads */ | ||
98 | # define THREAD_LOCK() | ||
99 | # define THREAD_UNLOCK() | ||
100 | # define THREAD_LOCK_INIT() | ||
101 | #endif | ||
54 | 102 | ||
55 | #define NULL 0 | 103 | /* |
104 | * No user serviceable parts behind this point. | ||
105 | * | ||
106 | * This structure describes a page worth of chunks. | ||
107 | */ | ||
56 | 108 | ||
57 | static void morecore(); | 109 | struct pginfo { |
58 | static int findbucket(); | 110 | struct pginfo *next; /* next on the free list */ |
111 | void *page; /* Pointer to the page */ | ||
112 | u_short size; /* size of this page's chunks */ | ||
113 | u_short shift; /* How far to shift for this size chunks */ | ||
114 | u_short free; /* How many free chunks */ | ||
115 | u_short total; /* How many chunk */ | ||
116 | u_long bits[1]; /* Which chunks are free */ | ||
117 | }; | ||
59 | 118 | ||
60 | /* | 119 | /* |
61 | * The overhead on a block is at least 4 bytes. When free, this space | 120 | * This structure describes a number of free pages. |
62 | * contains a pointer to the next free block, and the bottom two bits must | ||
63 | * be zero. When in use, the first byte is set to MAGIC, and the second | ||
64 | * byte is the size index. The remaining bytes are for alignment. | ||
65 | * If range checking is enabled then a second word holds the size of the | ||
66 | * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC). | ||
67 | * The order of elements is critical: ov_magic must overlay the low order | ||
68 | * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern. | ||
69 | */ | 121 | */ |
70 | union overhead { | 122 | |
71 | union overhead *ov_next; /* when free */ | 123 | struct pgfree { |
72 | struct { | 124 | struct pgfree *next; /* next run of free pages */ |
73 | u_char ovu_magic; /* magic number */ | 125 | struct pgfree *prev; /* prev run of free pages */ |
74 | u_char ovu_index; /* bucket # */ | 126 | void *page; /* pointer to free pages */ |
75 | #ifdef RCHECK | 127 | void *end; /* pointer to end of free pages */ |
76 | u_short ovu_rmagic; /* range magic number */ | 128 | u_long size; /* number of bytes free */ |
77 | u_long ovu_size; /* actual block size */ | ||
78 | #endif | ||
79 | } ovu; | ||
80 | #define ov_magic ovu.ovu_magic | ||
81 | #define ov_index ovu.ovu_index | ||
82 | #define ov_rmagic ovu.ovu_rmagic | ||
83 | #define ov_size ovu.ovu_size | ||
84 | }; | 129 | }; |
85 | 130 | ||
86 | #define MAGIC 0xef /* magic # on accounting info */ | 131 | /* |
87 | #define RMAGIC 0x5555 /* magic # on range info */ | 132 | * How many bits per u_long in the bitmap. |
133 | * Change only if not 8 bits/byte | ||
134 | */ | ||
135 | #define MALLOC_BITS (8*sizeof(u_long)) | ||
136 | |||
137 | /* | ||
138 | * Magic values to put in the page_directory | ||
139 | */ | ||
140 | #define MALLOC_NOT_MINE ((struct pginfo*) 0) | ||
141 | #define MALLOC_FREE ((struct pginfo*) 1) | ||
142 | #define MALLOC_FIRST ((struct pginfo*) 2) | ||
143 | #define MALLOC_FOLLOW ((struct pginfo*) 3) | ||
144 | #define MALLOC_MAGIC ((struct pginfo*) 4) | ||
145 | |||
146 | #ifndef malloc_pageshift | ||
147 | #define malloc_pageshift (PGSHIFT) | ||
148 | #endif | ||
149 | |||
150 | #ifndef malloc_minsize | ||
151 | #define malloc_minsize 16U | ||
152 | #endif | ||
153 | |||
154 | #ifndef malloc_pageshift | ||
155 | #error "malloc_pageshift undefined" | ||
156 | #endif | ||
157 | |||
158 | #if !defined(malloc_pagesize) | ||
159 | #define malloc_pagesize (1UL<<malloc_pageshift) | ||
160 | #endif | ||
161 | |||
162 | #if ((1UL<<malloc_pageshift) != malloc_pagesize) | ||
163 | #error "(1UL<<malloc_pageshift) != malloc_pagesize" | ||
164 | #endif | ||
165 | |||
166 | #ifndef malloc_maxsize | ||
167 | #define malloc_maxsize ((malloc_pagesize)>>1) | ||
168 | #endif | ||
88 | 169 | ||
89 | #ifdef RCHECK | 170 | /* A mask for the offset inside a page. */ |
90 | #define RSLOP sizeof (u_short) | 171 | #define malloc_pagemask ((malloc_pagesize)-1) |
172 | |||
173 | #define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask))) | ||
174 | #define ptr2index(foo) (((u_long)(foo) >> malloc_pageshift)-malloc_origo) | ||
175 | |||
176 | /* fd of /dev/zero */ | ||
177 | #ifdef USE_DEV_ZERO | ||
178 | static int fdzero; | ||
179 | #define MMAP_FD fdzero | ||
180 | #define INIT_MMAP() \ | ||
181 | { if ((fdzero=open("/dev/zero", O_RDWR, 0000)) == -1) \ | ||
182 | wrterror("open of /dev/zero"); } | ||
91 | #else | 183 | #else |
92 | #define RSLOP 0 | 184 | #define MMAP_FD (-1) |
185 | #define INIT_MMAP() | ||
186 | #endif | ||
187 | |||
188 | /* Set when initialization has been done */ | ||
189 | static unsigned int malloc_started; | ||
190 | |||
191 | /* Number of free pages we cache */ | ||
192 | static unsigned int malloc_cache = 16; | ||
193 | |||
194 | /* The offset from pagenumber to index into the page directory */ | ||
195 | static u_long malloc_origo; | ||
196 | |||
197 | /* The last index in the page directory we care about */ | ||
198 | static u_long last_index; | ||
199 | |||
200 | /* Pointer to page directory. Allocated "as if with" malloc */ | ||
201 | static struct pginfo **page_dir; | ||
202 | |||
203 | /* How many slots in the page directory */ | ||
204 | static size_t malloc_ninfo; | ||
205 | |||
206 | /* Free pages line up here */ | ||
207 | static struct pgfree free_list; | ||
208 | |||
209 | /* Abort(), user doesn't handle problems. */ | ||
210 | static int malloc_abort; | ||
211 | |||
212 | /* Are we trying to die ? */ | ||
213 | static int suicide; | ||
214 | |||
215 | #ifdef MALLOC_STATS | ||
216 | /* dump statistics */ | ||
217 | static int malloc_stats; | ||
218 | #endif | ||
219 | |||
220 | /* avoid outputting warnings? */ | ||
221 | static int malloc_silent; | ||
222 | |||
223 | /* always realloc ? */ | ||
224 | static int malloc_realloc; | ||
225 | |||
226 | #if defined(__FreeBSD__) || (defined(__OpenBSD__) && defined(MADV_FREE)) | ||
227 | /* pass the kernel a hint on free pages ? */ | ||
228 | static int malloc_hint; | ||
229 | #endif | ||
230 | |||
231 | /* xmalloc behaviour ? */ | ||
232 | static int malloc_xmalloc; | ||
233 | |||
234 | /* zero fill ? */ | ||
235 | static int malloc_zero; | ||
236 | |||
237 | /* junk fill ? */ | ||
238 | static int malloc_junk; | ||
239 | |||
240 | #ifdef __FreeBSD__ | ||
241 | /* utrace ? */ | ||
242 | static int malloc_utrace; | ||
243 | |||
244 | struct ut { void *p; size_t s; void *r; }; | ||
245 | |||
246 | void utrace(struct ut *, int); | ||
247 | |||
248 | #define UTRACE(a, b, c) \ | ||
249 | if (malloc_utrace) \ | ||
250 | {struct ut u; u.p=a; u.s = b; u.r=c; utrace(&u, sizeof u);} | ||
251 | #else /* !__FreeBSD__ */ | ||
252 | #define UTRACE(a,b,c) | ||
93 | #endif | 253 | #endif |
94 | 254 | ||
255 | /* my last break. */ | ||
256 | static void *malloc_brk; | ||
257 | |||
258 | /* one location cache for free-list holders */ | ||
259 | static struct pgfree *px; | ||
260 | |||
261 | /* compile-time options */ | ||
262 | char *malloc_options; | ||
263 | |||
264 | /* Name of the current public function */ | ||
265 | static char *malloc_func; | ||
266 | |||
267 | /* Macro for mmap */ | ||
268 | #define MMAP(size) \ | ||
269 | mmap((void *)0, (size), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, \ | ||
270 | MMAP_FD, (off_t)0); | ||
271 | |||
95 | /* | 272 | /* |
96 | * nextf[i] is the pointer to the next free block of size 2^(i+3). The | 273 | * Necessary function declarations |
97 | * smallest allocatable block is 8 bytes. The overhead information | ||
98 | * precedes the data area returned to the user. | ||
99 | */ | 274 | */ |
100 | #define NBUCKETS 30 | 275 | static int extend_pgdir(u_long index); |
101 | static union overhead *nextf[NBUCKETS]; | 276 | static void *imalloc(size_t size); |
102 | extern char *sbrk(); | 277 | static void ifree(void *ptr); |
278 | static void *irealloc(void *ptr, size_t size); | ||
279 | static void *malloc_bytes(size_t size); | ||
280 | |||
281 | #ifdef MALLOC_STATS | ||
282 | void | ||
283 | malloc_dump(fd) | ||
284 | FILE *fd; | ||
285 | { | ||
286 | struct pginfo **pd; | ||
287 | struct pgfree *pf; | ||
288 | int j; | ||
289 | |||
290 | pd = page_dir; | ||
291 | |||
292 | /* print out all the pages */ | ||
293 | for(j=0;j<=last_index;j++) { | ||
294 | fprintf(fd, "%08lx %5d ", (j+malloc_origo) << malloc_pageshift, j); | ||
295 | if (pd[j] == MALLOC_NOT_MINE) { | ||
296 | for(j++;j<=last_index && pd[j] == MALLOC_NOT_MINE;j++) | ||
297 | ; | ||
298 | j--; | ||
299 | fprintf(fd, ".. %5d not mine\n", j); | ||
300 | } else if (pd[j] == MALLOC_FREE) { | ||
301 | for(j++;j<=last_index && pd[j] == MALLOC_FREE;j++) | ||
302 | ; | ||
303 | j--; | ||
304 | fprintf(fd, ".. %5d free\n", j); | ||
305 | } else if (pd[j] == MALLOC_FIRST) { | ||
306 | for(j++;j<=last_index && pd[j] == MALLOC_FOLLOW;j++) | ||
307 | ; | ||
308 | j--; | ||
309 | fprintf(fd, ".. %5d in use\n", j); | ||
310 | } else if (pd[j] < MALLOC_MAGIC) { | ||
311 | fprintf(fd, "(%p)\n", pd[j]); | ||
312 | } else { | ||
313 | fprintf(fd, "%p %d (of %d) x %d @ %p --> %p\n", | ||
314 | pd[j], pd[j]->free, pd[j]->total, | ||
315 | pd[j]->size, pd[j]->page, pd[j]->next); | ||
316 | } | ||
317 | } | ||
318 | |||
319 | for(pf=free_list.next; pf; pf=pf->next) { | ||
320 | fprintf(fd, "Free: @%p [%p...%p[ %ld ->%p <-%p\n", | ||
321 | pf, pf->page, pf->end, pf->size, pf->prev, pf->next); | ||
322 | if (pf == pf->next) { | ||
323 | fprintf(fd, "Free_list loops.\n"); | ||
324 | break; | ||
325 | } | ||
326 | } | ||
327 | |||
328 | /* print out various info */ | ||
329 | fprintf(fd, "Minsize\t%d\n", malloc_minsize); | ||
330 | fprintf(fd, "Maxsize\t%d\n", malloc_maxsize); | ||
331 | fprintf(fd, "Pagesize\t%lu\n", (u_long)malloc_pagesize); | ||
332 | fprintf(fd, "Pageshift\t%d\n", malloc_pageshift); | ||
333 | fprintf(fd, "FirstPage\t%ld\n", malloc_origo); | ||
334 | fprintf(fd, "LastPage\t%ld %lx\n", last_index+malloc_pageshift, | ||
335 | (last_index + malloc_pageshift) << malloc_pageshift); | ||
336 | fprintf(fd, "Break\t%ld\n", (u_long)sbrk(0) >> malloc_pageshift); | ||
337 | } | ||
338 | #endif /* MALLOC_STATS */ | ||
339 | |||
340 | extern char *__progname; | ||
341 | |||
342 | static void | ||
343 | wrterror(p) | ||
344 | char *p; | ||
345 | { | ||
346 | char *q = " error: "; | ||
347 | struct iovec iov[4]; | ||
348 | |||
349 | iov[0].iov_base = __progname; | ||
350 | iov[0].iov_len = strlen(__progname); | ||
351 | iov[1].iov_base = malloc_func; | ||
352 | iov[1].iov_len = strlen(malloc_func); | ||
353 | iov[2].iov_base = q; | ||
354 | iov[2].iov_len = strlen(q); | ||
355 | iov[3].iov_base = p; | ||
356 | iov[3].iov_len = strlen(p); | ||
357 | writev(STDERR_FILENO, iov, 4); | ||
358 | |||
359 | suicide = 1; | ||
360 | #ifdef MALLOC_STATS | ||
361 | if (malloc_stats) | ||
362 | malloc_dump(stderr); | ||
363 | #endif /* MALLOC_STATS */ | ||
364 | abort(); | ||
365 | } | ||
366 | |||
367 | static void | ||
368 | wrtwarning(p) | ||
369 | char *p; | ||
370 | { | ||
371 | char *q = " warning: "; | ||
372 | struct iovec iov[4]; | ||
373 | |||
374 | if (malloc_abort) | ||
375 | wrterror(p); | ||
376 | else if (malloc_silent) | ||
377 | return; | ||
378 | |||
379 | iov[0].iov_base = __progname; | ||
380 | iov[0].iov_len = strlen(__progname); | ||
381 | iov[1].iov_base = malloc_func; | ||
382 | iov[1].iov_len = strlen(malloc_func); | ||
383 | iov[2].iov_base = q; | ||
384 | iov[2].iov_len = strlen(q); | ||
385 | iov[3].iov_base = p; | ||
386 | iov[3].iov_len = strlen(p); | ||
387 | writev(STDERR_FILENO, iov, 4); | ||
388 | } | ||
389 | |||
390 | #ifdef MALLOC_STATS | ||
391 | static void | ||
392 | malloc_exit() | ||
393 | { | ||
394 | FILE *fd = fopen("malloc.out", "a"); | ||
395 | char *q = "malloc() warning: Couldn't dump stats.\n"; | ||
396 | if (fd) { | ||
397 | malloc_dump(fd); | ||
398 | fclose(fd); | ||
399 | } else | ||
400 | write(2, q, strlen(q)); | ||
401 | } | ||
402 | #endif /* MALLOC_STATS */ | ||
103 | 403 | ||
104 | static int pagesz; /* page size */ | ||
105 | static int pagebucket; /* page size bucket */ | ||
106 | 404 | ||
107 | #ifdef MSTATS | ||
108 | /* | 405 | /* |
109 | * nmalloc[i] is the difference between the number of mallocs and frees | 406 | * Allocate a number of pages from the OS |
110 | * for a given block size. | ||
111 | */ | 407 | */ |
112 | static u_int nmalloc[NBUCKETS]; | 408 | static void * |
113 | #include <stdio.h> | 409 | map_pages(pages) |
114 | #endif | 410 | int pages; |
411 | { | ||
412 | caddr_t result, tail; | ||
115 | 413 | ||
116 | #if defined(DEBUG) || defined(RCHECK) | 414 | result = (caddr_t)pageround((u_long)sbrk(0)); |
117 | #define ASSERT(p) if (!(p)) botch("p") | 415 | tail = result + (pages << malloc_pageshift); |
118 | #include <stdio.h> | 416 | |
119 | static | 417 | if (brk(tail)) { |
120 | botch(s) | 418 | #ifdef MALLOC_EXTRA_SANITY |
121 | char *s; | 419 | wrterror("(ES): map_pages fails\n"); |
420 | #endif /* MALLOC_EXTRA_SANITY */ | ||
421 | return 0; | ||
422 | } | ||
423 | |||
424 | last_index = ptr2index(tail) - 1; | ||
425 | malloc_brk = tail; | ||
426 | |||
427 | if ((last_index+1) >= malloc_ninfo && !extend_pgdir(last_index)) | ||
428 | return 0; | ||
429 | |||
430 | return result; | ||
431 | } | ||
432 | |||
433 | /* | ||
434 | * Extend page directory | ||
435 | */ | ||
436 | static int | ||
437 | extend_pgdir(index) | ||
438 | u_long index; | ||
122 | { | 439 | { |
123 | fprintf(stderr, "\r\nassertion botched: %s\r\n", s); | 440 | struct pginfo **new, **old; |
124 | (void) fflush(stderr); /* just in case user buffered it */ | 441 | size_t i, oldlen; |
125 | abort(); | 442 | |
443 | /* Make it this many pages */ | ||
444 | i = index * sizeof *page_dir; | ||
445 | i /= malloc_pagesize; | ||
446 | i += 2; | ||
447 | |||
448 | /* remember the old mapping size */ | ||
449 | oldlen = malloc_ninfo * sizeof *page_dir; | ||
450 | |||
451 | /* | ||
452 | * NOTE: we allocate new pages and copy the directory rather than tempt | ||
453 | * fate by trying to "grow" the region.. There is nothing to prevent | ||
454 | * us from accidently re-mapping space that's been allocated by our caller | ||
455 | * via dlopen() or other mmap(). | ||
456 | * | ||
457 | * The copy problem is not too bad, as there is 4K of page index per | ||
458 | * 4MB of malloc arena. | ||
459 | * | ||
460 | * We can totally avoid the copy if we open a file descriptor to associate | ||
461 | * the anon mappings with. Then, when we remap the pages at the new | ||
462 | * address, the old pages will be "magically" remapped.. But this means | ||
463 | * keeping open a "secret" file descriptor..... | ||
464 | */ | ||
465 | |||
466 | /* Get new pages */ | ||
467 | new = (struct pginfo**) MMAP(i * malloc_pagesize); | ||
468 | if (new == MAP_FAILED) | ||
469 | return 0; | ||
470 | |||
471 | /* Copy the old stuff */ | ||
472 | memcpy(new, page_dir, | ||
473 | malloc_ninfo * sizeof *page_dir); | ||
474 | |||
475 | /* register the new size */ | ||
476 | malloc_ninfo = i * malloc_pagesize / sizeof *page_dir; | ||
477 | |||
478 | /* swap the pointers */ | ||
479 | old = page_dir; | ||
480 | page_dir = new; | ||
481 | |||
482 | /* Now free the old stuff */ | ||
483 | munmap(old, oldlen); | ||
484 | return 1; | ||
126 | } | 485 | } |
127 | #else | ||
128 | #define ASSERT(p) | ||
129 | #endif | ||
130 | 486 | ||
131 | void * | 487 | /* |
132 | malloc(nbytes) | 488 | * Initialize the world |
133 | size_t nbytes; | 489 | */ |
490 | static void | ||
491 | malloc_init () | ||
134 | { | 492 | { |
135 | register union overhead *op; | 493 | char *p, b[64]; |
136 | register long bucket, n; | 494 | int i, j; |
137 | register unsigned amt; | 495 | int save_errno = errno; |
138 | 496 | ||
139 | /* | 497 | THREAD_LOCK_INIT(); |
140 | * First time malloc is called, setup page size and | 498 | |
141 | * align break pointer so all data will be page aligned. | 499 | INIT_MMAP(); |
142 | */ | 500 | |
143 | if (pagesz == 0) { | 501 | #ifdef MALLOC_EXTRA_SANITY |
144 | pagesz = n = getpagesize(); | 502 | malloc_junk = 1; |
145 | op = (union overhead *)sbrk(0); | 503 | #endif /* MALLOC_EXTRA_SANITY */ |
146 | n = n - sizeof (*op) - ((long)op & (n - 1)); | 504 | |
147 | if (n < 0) | 505 | for (i = 0; i < 3; i++) { |
148 | n += pagesz; | 506 | if (i == 0) { |
149 | if (n) { | 507 | j = readlink("/etc/malloc.conf", b, sizeof b - 1); |
150 | if (sbrk(n) == (char *)-1) | 508 | if (j <= 0) |
151 | return (NULL); | 509 | continue; |
152 | } | 510 | b[j] = '\0'; |
153 | bucket = 0; | 511 | p = b; |
154 | amt = 8; | 512 | } else if (i == 1) { |
155 | while (pagesz > amt) { | 513 | if (issetugid() == 0) |
156 | amt <<= 1; | 514 | p = getenv("MALLOC_OPTIONS"); |
157 | bucket++; | 515 | else |
158 | } | 516 | continue; |
159 | pagebucket = bucket; | 517 | } else if (i == 2) { |
160 | } | 518 | p = malloc_options; |
161 | /* | ||
162 | * Convert amount of memory requested into closest block size | ||
163 | * stored in hash buckets which satisfies request. | ||
164 | * Account for space used per block for accounting. | ||
165 | */ | ||
166 | if (nbytes <= (n = pagesz - sizeof (*op) - RSLOP)) { | ||
167 | #ifndef RCHECK | ||
168 | amt = 8; /* size of first bucket */ | ||
169 | bucket = 0; | ||
170 | #else | ||
171 | amt = 16; /* size of first bucket */ | ||
172 | bucket = 1; | ||
173 | #endif | ||
174 | n = -((long)sizeof (*op) + RSLOP); | ||
175 | } else { | ||
176 | amt = pagesz; | ||
177 | bucket = pagebucket; | ||
178 | } | 519 | } |
179 | while (nbytes > amt + n) { | 520 | for (; p && *p; p++) { |
180 | amt <<= 1; | 521 | switch (*p) { |
181 | if (amt == 0) | 522 | case '>': malloc_cache <<= 1; break; |
182 | return (NULL); | 523 | case '<': malloc_cache >>= 1; break; |
183 | bucket++; | 524 | case 'a': malloc_abort = 0; break; |
525 | case 'A': malloc_abort = 1; break; | ||
526 | #ifdef MALLOC_STATS | ||
527 | case 'd': malloc_stats = 0; break; | ||
528 | case 'D': malloc_stats = 1; break; | ||
529 | #endif /* MALLOC_STATS */ | ||
530 | #if defined(__FreeBSD__) || (defined(__OpenBSD__) && defined(MADV_FREE)) | ||
531 | case 'h': malloc_hint = 0; break; | ||
532 | case 'H': malloc_hint = 1; break; | ||
533 | #endif /* __FreeBSD__ */ | ||
534 | case 'r': malloc_realloc = 0; break; | ||
535 | case 'R': malloc_realloc = 1; break; | ||
536 | case 'j': malloc_junk = 0; break; | ||
537 | case 'J': malloc_junk = 1; break; | ||
538 | case 'n': malloc_silent = 0; break; | ||
539 | case 'N': malloc_silent = 1; break; | ||
540 | #ifdef __FreeBSD__ | ||
541 | case 'u': malloc_utrace = 0; break; | ||
542 | case 'U': malloc_utrace = 1; break; | ||
543 | #endif /* __FreeBSD__ */ | ||
544 | case 'x': malloc_xmalloc = 0; break; | ||
545 | case 'X': malloc_xmalloc = 1; break; | ||
546 | case 'z': malloc_zero = 0; break; | ||
547 | case 'Z': malloc_zero = 1; break; | ||
548 | default: | ||
549 | j = malloc_abort; | ||
550 | malloc_abort = 0; | ||
551 | wrtwarning("unknown char in MALLOC_OPTIONS\n"); | ||
552 | malloc_abort = j; | ||
553 | break; | ||
554 | } | ||
184 | } | 555 | } |
185 | /* | 556 | } |
186 | * If nothing in hash bucket right now, | 557 | |
187 | * request more memory from the system. | 558 | UTRACE(0, 0, 0); |
188 | */ | 559 | |
189 | if ((op = nextf[bucket]) == NULL) { | 560 | /* |
190 | morecore(bucket); | 561 | * We want junk in the entire allocation, and zero only in the part |
191 | if ((op = nextf[bucket]) == NULL) | 562 | * the user asked for. |
192 | return (NULL); | 563 | */ |
564 | if (malloc_zero) | ||
565 | malloc_junk=1; | ||
566 | |||
567 | #ifdef MALLOC_STATS | ||
568 | if (malloc_stats) | ||
569 | atexit(malloc_exit); | ||
570 | #endif /* MALLOC_STATS */ | ||
571 | |||
572 | /* Allocate one page for the page directory */ | ||
573 | page_dir = (struct pginfo **) MMAP(malloc_pagesize); | ||
574 | |||
575 | if (page_dir == MAP_FAILED) | ||
576 | wrterror("mmap(2) failed, check limits.\n"); | ||
577 | |||
578 | /* | ||
579 | * We need a maximum of malloc_pageshift buckets, steal these from the | ||
580 | * front of the page_directory; | ||
581 | */ | ||
582 | malloc_origo = ((u_long)pageround((u_long)sbrk(0))) >> malloc_pageshift; | ||
583 | malloc_origo -= malloc_pageshift; | ||
584 | |||
585 | malloc_ninfo = malloc_pagesize / sizeof *page_dir; | ||
586 | |||
587 | /* Been here, done that */ | ||
588 | malloc_started++; | ||
589 | |||
590 | /* Recalculate the cache size in bytes, and make sure it's nonzero */ | ||
591 | |||
592 | if (!malloc_cache) | ||
593 | malloc_cache++; | ||
594 | |||
595 | malloc_cache <<= malloc_pageshift; | ||
596 | |||
597 | /* | ||
598 | * This is a nice hack from Kaleb Keithly (kaleb@x.org). | ||
599 | * We can sbrk(2) further back when we keep this on a low address. | ||
600 | */ | ||
601 | px = (struct pgfree *) imalloc (sizeof *px); | ||
602 | errno = save_errno; | ||
603 | } | ||
604 | |||
605 | /* | ||
606 | * Allocate a number of complete pages | ||
607 | */ | ||
608 | static void * | ||
609 | malloc_pages(size) | ||
610 | size_t size; | ||
611 | { | ||
612 | void *p, *delay_free = 0; | ||
613 | int i; | ||
614 | struct pgfree *pf; | ||
615 | u_long index; | ||
616 | |||
617 | size = pageround(size); | ||
618 | |||
619 | p = 0; | ||
620 | /* Look for free pages before asking for more */ | ||
621 | for(pf = free_list.next; pf; pf = pf->next) { | ||
622 | |||
623 | #ifdef MALLOC_EXTRA_SANITY | ||
624 | if (pf->size & malloc_pagemask) | ||
625 | wrterror("(ES): junk length entry on free_list\n"); | ||
626 | if (!pf->size) | ||
627 | wrterror("(ES): zero length entry on free_list\n"); | ||
628 | if (pf->page == pf->end) | ||
629 | wrterror("(ES): zero entry on free_list\n"); | ||
630 | if (pf->page > pf->end) | ||
631 | wrterror("(ES): sick entry on free_list\n"); | ||
632 | if ((void*)pf->page >= (void*)sbrk(0)) | ||
633 | wrterror("(ES): entry on free_list past brk\n"); | ||
634 | if (page_dir[ptr2index(pf->page)] != MALLOC_FREE) | ||
635 | wrterror("(ES): non-free first page on free-list\n"); | ||
636 | if (page_dir[ptr2index(pf->end)-1] != MALLOC_FREE) | ||
637 | wrterror("(ES): non-free last page on free-list\n"); | ||
638 | #endif /* MALLOC_EXTRA_SANITY */ | ||
639 | |||
640 | if (pf->size < size) | ||
641 | continue; | ||
642 | |||
643 | if (pf->size == size) { | ||
644 | p = pf->page; | ||
645 | if (pf->next) | ||
646 | pf->next->prev = pf->prev; | ||
647 | pf->prev->next = pf->next; | ||
648 | delay_free = pf; | ||
649 | break; | ||
193 | } | 650 | } |
194 | /* remove from linked list */ | 651 | |
195 | nextf[bucket] = op->ov_next; | 652 | p = pf->page; |
196 | op->ov_magic = MAGIC; | 653 | pf->page = (char *)pf->page + size; |
197 | op->ov_index = bucket; | 654 | pf->size -= size; |
198 | #ifdef MSTATS | 655 | break; |
199 | nmalloc[bucket]++; | 656 | } |
200 | #endif | 657 | |
201 | #ifdef RCHECK | 658 | #ifdef MALLOC_EXTRA_SANITY |
202 | /* | 659 | if (p && page_dir[ptr2index(p)] != MALLOC_FREE) |
203 | * Record allocated size of block and | 660 | wrterror("(ES): allocated non-free page on free-list\n"); |
204 | * bound space with magic numbers. | 661 | #endif /* MALLOC_EXTRA_SANITY */ |
205 | */ | 662 | |
206 | op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); | 663 | size >>= malloc_pageshift; |
207 | op->ov_rmagic = RMAGIC; | 664 | |
208 | *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; | 665 | /* Map new pages */ |
209 | #endif | 666 | if (!p) |
210 | return ((char *)(op + 1)); | 667 | p = map_pages(size); |
668 | |||
669 | if (p) { | ||
670 | |||
671 | index = ptr2index(p); | ||
672 | page_dir[index] = MALLOC_FIRST; | ||
673 | for (i=1;i<size;i++) | ||
674 | page_dir[index+i] = MALLOC_FOLLOW; | ||
675 | |||
676 | if (malloc_junk) | ||
677 | memset(p, SOME_JUNK, size << malloc_pageshift); | ||
678 | } | ||
679 | |||
680 | if (delay_free) { | ||
681 | if (!px) | ||
682 | px = delay_free; | ||
683 | else | ||
684 | ifree(delay_free); | ||
685 | } | ||
686 | |||
687 | return p; | ||
211 | } | 688 | } |
212 | 689 | ||
213 | /* | 690 | /* |
214 | * Allocate more memory to the indicated bucket. | 691 | * Allocate a page of fragments |
215 | */ | 692 | */ |
216 | static void | 693 | |
217 | morecore(bucket) | 694 | static __inline__ int |
218 | int bucket; | 695 | malloc_make_chunks(bits) |
696 | int bits; | ||
219 | { | 697 | { |
220 | register union overhead *op; | 698 | struct pginfo *bp; |
221 | register long sz; /* size of desired block */ | 699 | void *pp; |
222 | long amt; /* amount to allocate */ | 700 | int i, k, l; |
223 | int nblks; /* how many blocks we get */ | ||
224 | 701 | ||
225 | /* | 702 | /* Allocate a new bucket */ |
226 | * sbrk_size <= 0 only for big, FLUFFY, requests (about | 703 | pp = malloc_pages((size_t)malloc_pagesize); |
227 | * 2^30 bytes on a VAX, I think) or for a negative arg. | 704 | if (!pp) |
228 | */ | 705 | return 0; |
229 | sz = 1 << (bucket + 3); | 706 | |
230 | #ifdef DEBUG | 707 | /* Find length of admin structure */ |
231 | ASSERT(sz > 0); | 708 | l = sizeof *bp - sizeof(u_long); |
232 | #else | 709 | l += sizeof(u_long) * |
233 | if (sz <= 0) | 710 | (((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS); |
234 | return; | 711 | |
235 | #endif | 712 | /* Don't waste more than two chunks on this */ |
236 | if (sz < pagesz) { | 713 | /* |
237 | amt = pagesz; | 714 | * If we are to allocate a memory protected page for the malloc(0) |
238 | nblks = amt / sz; | 715 | * case (when bits=0), it must be from a different page than the |
239 | } else { | 716 | * pginfo page. |
240 | amt = sz + pagesz; | 717 | * --> Treat it like the big chunk alloc, get a second data page. |
241 | nblks = 1; | 718 | */ |
719 | if (bits != 0 && (1UL<<(bits)) <= l+l) { | ||
720 | bp = (struct pginfo *)pp; | ||
721 | } else { | ||
722 | bp = (struct pginfo *)imalloc(l); | ||
723 | if (!bp) { | ||
724 | ifree(pp); | ||
725 | return 0; | ||
242 | } | 726 | } |
243 | op = (union overhead *)sbrk(amt); | 727 | } |
244 | /* no more room! */ | 728 | |
245 | if ((long)op == -1) | 729 | /* memory protect the page allocated in the malloc(0) case */ |
246 | return; | 730 | if (bits == 0) { |
247 | /* | 731 | |
248 | * Add new memory allocated to that on | 732 | bp->size = 0; |
249 | * free list for this hash bucket. | 733 | bp->shift = 1; |
250 | */ | 734 | i = malloc_minsize-1; |
251 | nextf[bucket] = op; | 735 | while (i >>= 1) |
252 | while (--nblks > 0) { | 736 | bp->shift++; |
253 | op->ov_next = (union overhead *)((caddr_t)op + sz); | 737 | bp->total = bp->free = malloc_pagesize >> bp->shift; |
254 | op = (union overhead *)((caddr_t)op + sz); | 738 | bp->page = pp; |
255 | } | 739 | |
740 | k = mprotect(pp, malloc_pagesize, PROT_NONE); | ||
741 | if (k < 0) { | ||
742 | ifree(pp); | ||
743 | ifree(bp); | ||
744 | return 0; | ||
745 | } | ||
746 | } else { | ||
747 | bp->size = (1UL<<bits); | ||
748 | bp->shift = bits; | ||
749 | bp->total = bp->free = malloc_pagesize >> bits; | ||
750 | bp->page = pp; | ||
751 | } | ||
752 | |||
753 | /* set all valid bits in the bitmap */ | ||
754 | k = bp->total; | ||
755 | i = 0; | ||
756 | |||
757 | /* Do a bunch at a time */ | ||
758 | for(;k-i >= MALLOC_BITS; i += MALLOC_BITS) | ||
759 | bp->bits[i / MALLOC_BITS] = ~0UL; | ||
760 | |||
761 | for(; i < k; i++) | ||
762 | bp->bits[i/MALLOC_BITS] |= 1UL<<(i%MALLOC_BITS); | ||
763 | |||
764 | if (bp == bp->page) { | ||
765 | /* Mark the ones we stole for ourselves */ | ||
766 | for(i=0;l > 0;i++) { | ||
767 | bp->bits[i/MALLOC_BITS] &= ~(1UL<<(i%MALLOC_BITS)); | ||
768 | bp->free--; | ||
769 | bp->total--; | ||
770 | l -= (1 << bits); | ||
771 | } | ||
772 | } | ||
773 | |||
774 | /* MALLOC_LOCK */ | ||
775 | |||
776 | page_dir[ptr2index(pp)] = bp; | ||
777 | |||
778 | bp->next = page_dir[bits]; | ||
779 | page_dir[bits] = bp; | ||
780 | |||
781 | /* MALLOC_UNLOCK */ | ||
782 | |||
783 | return 1; | ||
256 | } | 784 | } |
257 | 785 | ||
258 | void | 786 | /* |
259 | free(cp) | 787 | * Allocate a fragment |
260 | void *cp; | 788 | */ |
261 | { | 789 | static void * |
262 | register long size; | 790 | malloc_bytes(size) |
263 | register union overhead *op; | 791 | size_t size; |
264 | 792 | { | |
265 | if (cp == NULL) | 793 | int i,j; |
266 | return; | 794 | u_long u; |
267 | op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); | 795 | struct pginfo *bp; |
268 | #ifdef DEBUG | 796 | int k; |
269 | ASSERT(op->ov_magic == MAGIC); /* make sure it was in use */ | 797 | u_long *lp; |
270 | #else | 798 | |
271 | if (op->ov_magic != MAGIC) | 799 | /* Don't bother with anything less than this */ |
272 | return; /* sanity */ | 800 | /* unless we have a malloc(0) requests */ |
273 | #endif | 801 | if (size != 0 && size < malloc_minsize) |
274 | #ifdef RCHECK | 802 | size = malloc_minsize; |
275 | ASSERT(op->ov_rmagic == RMAGIC); | 803 | |
276 | ASSERT(*(u_short *)((caddr_t)(op + 1) + op->ov_size) == RMAGIC); | 804 | /* Find the right bucket */ |
277 | #endif | 805 | if (size == 0) |
278 | size = op->ov_index; | 806 | j=0; |
279 | ASSERT(size < NBUCKETS); | 807 | else { |
280 | op->ov_next = nextf[size]; /* also clobbers ov_magic */ | 808 | j = 1; |
281 | nextf[size] = op; | 809 | i = size-1; |
282 | #ifdef MSTATS | 810 | while (i >>= 1) |
283 | nmalloc[size]--; | 811 | j++; |
284 | #endif | 812 | } |
813 | |||
814 | /* If it's empty, make a page more of that size chunks */ | ||
815 | if (!page_dir[j] && !malloc_make_chunks(j)) | ||
816 | return 0; | ||
817 | |||
818 | bp = page_dir[j]; | ||
819 | |||
820 | /* Find first word of bitmap which isn't empty */ | ||
821 | for (lp = bp->bits; !*lp; lp++) | ||
822 | ; | ||
823 | |||
824 | /* Find that bit, and tweak it */ | ||
825 | u = 1; | ||
826 | k = 0; | ||
827 | while (!(*lp & u)) { | ||
828 | u += u; | ||
829 | k++; | ||
830 | } | ||
831 | *lp ^= u; | ||
832 | |||
833 | /* If there are no more free, remove from free-list */ | ||
834 | if (!--bp->free) { | ||
835 | page_dir[j] = bp->next; | ||
836 | bp->next = 0; | ||
837 | } | ||
838 | |||
839 | /* Adjust to the real offset of that chunk */ | ||
840 | k += (lp-bp->bits)*MALLOC_BITS; | ||
841 | k <<= bp->shift; | ||
842 | |||
843 | if (malloc_junk && bp->size != 0) | ||
844 | memset((char *)bp->page + k, SOME_JUNK, bp->size); | ||
845 | |||
846 | return (u_char *)bp->page + k; | ||
285 | } | 847 | } |
286 | 848 | ||
287 | /* | 849 | /* |
288 | * When a program attempts "storage compaction" as mentioned in the | 850 | * Allocate a piece of memory |
289 | * old malloc man page, it realloc's an already freed block. Usually | ||
290 | * this is the last block it freed; occasionally it might be farther | ||
291 | * back. We have to search all the free lists for the block in order | ||
292 | * to determine its bucket: 1st we make one pass thru the lists | ||
293 | * checking only the first block in each; if that fails we search | ||
294 | * ``realloc_srchlen'' blocks in each list for a match (the variable | ||
295 | * is extern so the caller can modify it). If that fails we just copy | ||
296 | * however many bytes was given to realloc() and hope it's not huge. | ||
297 | */ | 851 | */ |
298 | int realloc_srchlen = 4; /* 4 should be plenty, -1 =>'s whole list */ | 852 | static void * |
853 | imalloc(size) | ||
854 | size_t size; | ||
855 | { | ||
856 | void *result; | ||
299 | 857 | ||
300 | void * | 858 | if (!malloc_started) |
301 | realloc(cp, nbytes) | 859 | malloc_init(); |
302 | void *cp; | 860 | |
303 | size_t nbytes; | 861 | if (suicide) |
304 | { | 862 | abort(); |
305 | register u_long onb; | 863 | |
306 | register long i; | 864 | if ((size + malloc_pagesize) < size) /* Check for overflow */ |
307 | union overhead *op; | 865 | result = 0; |
308 | char *res; | 866 | else if (size <= malloc_maxsize) |
309 | int was_alloced = 0; | 867 | result = malloc_bytes(size); |
310 | 868 | else | |
311 | if (cp == NULL) | 869 | result = malloc_pages(size); |
312 | return (malloc(nbytes)); | 870 | |
313 | op = (union overhead *)((caddr_t)cp - sizeof (union overhead)); | 871 | if (malloc_abort && !result) |
314 | if (op->ov_magic == MAGIC) { | 872 | wrterror("allocation failed.\n"); |
315 | was_alloced++; | 873 | |
316 | i = op->ov_index; | 874 | if (malloc_zero && result) |
317 | } else { | 875 | memset(result, 0, size); |
318 | /* | 876 | |
319 | * Already free, doing "compaction". | 877 | return result; |
320 | * | 878 | } |
321 | * Search for the old block of memory on the | 879 | |
322 | * free list. First, check the most common | 880 | /* |
323 | * case (last element free'd), then (this failing) | 881 | * Change the size of an allocation. |
324 | * the last ``realloc_srchlen'' items free'd. | 882 | */ |
325 | * If all lookups fail, then assume the size of | 883 | static void * |
326 | * the memory block being realloc'd is the | 884 | irealloc(ptr, size) |
327 | * largest possible (so that all "nbytes" of new | 885 | void *ptr; |
328 | * memory are copied into). Note that this could cause | 886 | size_t size; |
329 | * a memory fault if the old area was tiny, and the moon | 887 | { |
330 | * is gibbous. However, that is very unlikely. | 888 | void *p; |
331 | */ | 889 | u_long osize, index; |
332 | if ((i = findbucket(op, 1)) < 0 && | 890 | struct pginfo **mp; |
333 | (i = findbucket(op, realloc_srchlen)) < 0) | 891 | int i; |
334 | i = NBUCKETS; | 892 | |
893 | if (suicide) | ||
894 | abort(); | ||
895 | |||
896 | if (!malloc_started) { | ||
897 | wrtwarning("malloc() has never been called.\n"); | ||
898 | return 0; | ||
899 | } | ||
900 | |||
901 | index = ptr2index(ptr); | ||
902 | |||
903 | if (index < malloc_pageshift) { | ||
904 | wrtwarning("junk pointer, too low to make sense.\n"); | ||
905 | return 0; | ||
906 | } | ||
907 | |||
908 | if (index > last_index) { | ||
909 | wrtwarning("junk pointer, too high to make sense.\n"); | ||
910 | return 0; | ||
911 | } | ||
912 | |||
913 | mp = &page_dir[index]; | ||
914 | |||
915 | if (*mp == MALLOC_FIRST) { /* Page allocation */ | ||
916 | |||
917 | /* Check the pointer */ | ||
918 | if ((u_long)ptr & malloc_pagemask) { | ||
919 | wrtwarning("modified (page-) pointer.\n"); | ||
920 | return 0; | ||
335 | } | 921 | } |
336 | onb = 1 << (i + 3); | 922 | |
337 | if (onb < pagesz) | 923 | /* Find the size in bytes */ |
338 | onb -= sizeof (*op) + RSLOP; | 924 | for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;) |
339 | else | 925 | osize += malloc_pagesize; |
340 | onb += pagesz - sizeof (*op) - RSLOP; | 926 | |
341 | /* avoid the copy if same size block */ | 927 | if (!malloc_realloc && /* unless we have to, */ |
342 | if (was_alloced) { | 928 | size <= osize && /* .. or are too small, */ |
343 | if (i) { | 929 | size > (osize - malloc_pagesize)) { /* .. or can free a page, */ |
344 | i = 1 << (i + 2); | 930 | return ptr; /* don't do anything. */ |
345 | if (i < pagesz) | 931 | } |
346 | i -= sizeof (*op) + RSLOP; | 932 | |
347 | else | 933 | } else if (*mp >= MALLOC_MAGIC) { /* Chunk allocation */ |
348 | i += pagesz - sizeof (*op) - RSLOP; | 934 | |
349 | } | 935 | /* Check the pointer for sane values */ |
350 | if (nbytes <= onb && nbytes > i) { | 936 | if ((u_long)ptr & ((1UL<<((*mp)->shift))-1)) { |
351 | #ifdef RCHECK | 937 | wrtwarning("modified (chunk-) pointer.\n"); |
352 | op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1); | 938 | return 0; |
353 | *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC; | 939 | } |
354 | #endif | 940 | |
355 | return(cp); | 941 | /* Find the chunk index in the page */ |
356 | } else | 942 | i = ((u_long)ptr & malloc_pagemask) >> (*mp)->shift; |
357 | free(cp); | 943 | |
944 | /* Verify that it isn't a free chunk already */ | ||
945 | if ((*mp)->bits[i/MALLOC_BITS] & (1UL<<(i%MALLOC_BITS))) { | ||
946 | wrtwarning("chunk is already free.\n"); | ||
947 | return 0; | ||
358 | } | 948 | } |
359 | if ((res = malloc(nbytes)) == NULL) | 949 | |
360 | return (NULL); | 950 | osize = (*mp)->size; |
361 | if (cp != res) /* common optimization if "compacting" */ | 951 | |
362 | bcopy(cp, res, (nbytes < onb) ? nbytes : onb); | 952 | if (!malloc_realloc && /* Unless we have to, */ |
363 | return (res); | 953 | size < osize && /* ..or are too small, */ |
954 | (size > osize/2 || /* ..or could use a smaller size, */ | ||
955 | osize == malloc_minsize)) { /* ..(if there is one) */ | ||
956 | return ptr; /* ..Don't do anything */ | ||
957 | } | ||
958 | |||
959 | } else { | ||
960 | wrtwarning("pointer to wrong page.\n"); | ||
961 | return 0; | ||
962 | } | ||
963 | |||
964 | p = imalloc(size); | ||
965 | |||
966 | if (p) { | ||
967 | /* copy the lesser of the two sizes, and free the old one */ | ||
968 | /* Don't move from/to 0 sized region !!! */ | ||
969 | if (osize != 0 && size != 0) { | ||
970 | if (osize < size) | ||
971 | memcpy(p, ptr, osize); | ||
972 | else | ||
973 | memcpy(p, ptr, size); | ||
974 | } | ||
975 | ifree(ptr); | ||
976 | } | ||
977 | return p; | ||
364 | } | 978 | } |
365 | 979 | ||
366 | /* | 980 | /* |
367 | * Search ``srchlen'' elements of each free list for a block whose | 981 | * Free a sequence of pages |
368 | * header starts at ``freep''. If srchlen is -1 search the whole list. | ||
369 | * Return bucket number, or -1 if not found. | ||
370 | */ | 982 | */ |
371 | static | 983 | |
372 | findbucket(freep, srchlen) | 984 | static __inline__ void |
373 | union overhead *freep; | 985 | free_pages(ptr, index, info) |
374 | int srchlen; | 986 | void *ptr; |
987 | int index; | ||
988 | struct pginfo *info; | ||
375 | { | 989 | { |
376 | register union overhead *p; | 990 | int i; |
377 | register int i, j; | 991 | struct pgfree *pf, *pt=0; |
378 | 992 | u_long l; | |
379 | for (i = 0; i < NBUCKETS; i++) { | 993 | void *tail; |
380 | j = 0; | 994 | |
381 | for (p = nextf[i]; p && j != srchlen; p = p->ov_next) { | 995 | if (info == MALLOC_FREE) { |
382 | if (p == freep) | 996 | wrtwarning("page is already free.\n"); |
383 | return (i); | 997 | return; |
384 | j++; | 998 | } |
385 | } | 999 | |
1000 | if (info != MALLOC_FIRST) { | ||
1001 | wrtwarning("pointer to wrong page.\n"); | ||
1002 | return; | ||
1003 | } | ||
1004 | |||
1005 | if ((u_long)ptr & malloc_pagemask) { | ||
1006 | wrtwarning("modified (page-) pointer.\n"); | ||
1007 | return; | ||
1008 | } | ||
1009 | |||
1010 | /* Count how many pages and mark them free at the same time */ | ||
1011 | page_dir[index] = MALLOC_FREE; | ||
1012 | for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++) | ||
1013 | page_dir[index + i] = MALLOC_FREE; | ||
1014 | |||
1015 | l = i << malloc_pageshift; | ||
1016 | |||
1017 | if (malloc_junk) | ||
1018 | memset(ptr, SOME_JUNK, l); | ||
1019 | |||
1020 | #if defined(__FreeBSD__) || (defined(__OpenBSD__) && defined(MADV_FREE)) | ||
1021 | if (malloc_hint) | ||
1022 | madvise(ptr, l, MADV_FREE); | ||
1023 | #endif | ||
1024 | |||
1025 | tail = (char *)ptr+l; | ||
1026 | |||
1027 | /* add to free-list */ | ||
1028 | if (!px) | ||
1029 | px = imalloc(sizeof *px); /* This cannot fail... */ | ||
1030 | px->page = ptr; | ||
1031 | px->end = tail; | ||
1032 | px->size = l; | ||
1033 | if (!free_list.next) { | ||
1034 | |||
1035 | /* Nothing on free list, put this at head */ | ||
1036 | px->next = free_list.next; | ||
1037 | px->prev = &free_list; | ||
1038 | free_list.next = px; | ||
1039 | pf = px; | ||
1040 | px = 0; | ||
1041 | |||
1042 | } else { | ||
1043 | |||
1044 | /* Find the right spot, leave pf pointing to the modified entry. */ | ||
1045 | tail = (char *)ptr+l; | ||
1046 | |||
1047 | for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next) | ||
1048 | ; /* Race ahead here */ | ||
1049 | |||
1050 | if (pf->page > tail) { | ||
1051 | /* Insert before entry */ | ||
1052 | px->next = pf; | ||
1053 | px->prev = pf->prev; | ||
1054 | pf->prev = px; | ||
1055 | px->prev->next = px; | ||
1056 | pf = px; | ||
1057 | px = 0; | ||
1058 | } else if (pf->end == ptr ) { | ||
1059 | /* Append to the previous entry */ | ||
1060 | pf->end = (char *)pf->end + l; | ||
1061 | pf->size += l; | ||
1062 | if (pf->next && pf->end == pf->next->page ) { | ||
1063 | /* And collapse the next too. */ | ||
1064 | pt = pf->next; | ||
1065 | pf->end = pt->end; | ||
1066 | pf->size += pt->size; | ||
1067 | pf->next = pt->next; | ||
1068 | if (pf->next) | ||
1069 | pf->next->prev = pf; | ||
1070 | } | ||
1071 | } else if (pf->page == tail) { | ||
1072 | /* Prepend to entry */ | ||
1073 | pf->size += l; | ||
1074 | pf->page = ptr; | ||
1075 | } else if (!pf->next) { | ||
1076 | /* Append at tail of chain */ | ||
1077 | px->next = 0; | ||
1078 | px->prev = pf; | ||
1079 | pf->next = px; | ||
1080 | pf = px; | ||
1081 | px = 0; | ||
1082 | } else { | ||
1083 | wrterror("freelist is destroyed.\n"); | ||
386 | } | 1084 | } |
387 | return (-1); | 1085 | } |
1086 | |||
1087 | /* Return something to OS ? */ | ||
1088 | if (!pf->next && /* If we're the last one, */ | ||
1089 | pf->size > malloc_cache && /* ..and the cache is full, */ | ||
1090 | pf->end == malloc_brk && /* ..and none behind us, */ | ||
1091 | malloc_brk == sbrk(0)) { /* ..and it's OK to do... */ | ||
1092 | |||
1093 | /* | ||
1094 | * Keep the cache intact. Notice that the '>' above guarantees that | ||
1095 | * the pf will always have at least one page afterwards. | ||
1096 | */ | ||
1097 | pf->end = (char *)pf->page + malloc_cache; | ||
1098 | pf->size = malloc_cache; | ||
1099 | |||
1100 | brk(pf->end); | ||
1101 | malloc_brk = pf->end; | ||
1102 | |||
1103 | index = ptr2index(pf->end); | ||
1104 | last_index = index - 1; | ||
1105 | |||
1106 | for(i=index;i <= last_index;) | ||
1107 | page_dir[i++] = MALLOC_NOT_MINE; | ||
1108 | |||
1109 | /* XXX: We could realloc/shrink the pagedir here I guess. */ | ||
1110 | } | ||
1111 | if (pt) | ||
1112 | ifree(pt); | ||
388 | } | 1113 | } |
389 | 1114 | ||
390 | #ifdef MSTATS | ||
391 | /* | 1115 | /* |
392 | * mstats - print out statistics about malloc | 1116 | * Free a chunk, and possibly the page it's on, if the page becomes empty. |
393 | * | ||
394 | * Prints two lines of numbers, one showing the length of the free list | ||
395 | * for each size category, the second showing the number of mallocs - | ||
396 | * frees for each size category. | ||
397 | */ | 1117 | */ |
398 | mstats(s) | 1118 | |
399 | char *s; | 1119 | /* ARGSUSED */ |
1120 | static __inline__ void | ||
1121 | free_bytes(ptr, index, info) | ||
1122 | void *ptr; | ||
1123 | int index; | ||
1124 | struct pginfo *info; | ||
400 | { | 1125 | { |
401 | register int i, j; | 1126 | int i; |
402 | register union overhead *p; | 1127 | struct pginfo **mp; |
403 | int totfree = 0, | 1128 | void *vp; |
404 | totused = 0; | 1129 | |
405 | 1130 | /* Find the chunk number on the page */ | |
406 | fprintf(stderr, "Memory allocation statistics %s\nfree:\t", s); | 1131 | i = ((u_long)ptr & malloc_pagemask) >> info->shift; |
407 | for (i = 0; i < NBUCKETS; i++) { | 1132 | |
408 | for (j = 0, p = nextf[i]; p; p = p->ov_next, j++) | 1133 | if ((u_long)ptr & ((1UL<<(info->shift))-1)) { |
409 | ; | 1134 | wrtwarning("modified (chunk-) pointer.\n"); |
410 | fprintf(stderr, " %d", j); | 1135 | return; |
411 | totfree += j * (1 << (i + 3)); | 1136 | } |
412 | } | 1137 | |
413 | fprintf(stderr, "\nused:\t"); | 1138 | if (info->bits[i/MALLOC_BITS] & (1UL<<(i%MALLOC_BITS))) { |
414 | for (i = 0; i < NBUCKETS; i++) { | 1139 | wrtwarning("chunk is already free.\n"); |
415 | fprintf(stderr, " %d", nmalloc[i]); | 1140 | return; |
416 | totused += nmalloc[i] * (1 << (i + 3)); | 1141 | } |
417 | } | 1142 | |
418 | fprintf(stderr, "\n\tTotal in use: %d, total free: %d\n", | 1143 | if (malloc_junk && info->size != 0) |
419 | totused, totfree); | 1144 | memset(ptr, SOME_JUNK, info->size); |
1145 | |||
1146 | info->bits[i/MALLOC_BITS] |= 1UL<<(i%MALLOC_BITS); | ||
1147 | info->free++; | ||
1148 | |||
1149 | if (info->size != 0) | ||
1150 | mp = page_dir + info->shift; | ||
1151 | else | ||
1152 | mp = page_dir; | ||
1153 | |||
1154 | if (info->free == 1) { | ||
1155 | |||
1156 | /* Page became non-full */ | ||
1157 | |||
1158 | /* Insert in address order */ | ||
1159 | while (*mp && (*mp)->next && (*mp)->next->page < info->page) | ||
1160 | mp = &(*mp)->next; | ||
1161 | info->next = *mp; | ||
1162 | *mp = info; | ||
1163 | return; | ||
1164 | } | ||
1165 | |||
1166 | if (info->free != info->total) | ||
1167 | return; | ||
1168 | |||
1169 | /* Find & remove this page in the queue */ | ||
1170 | while (*mp != info) { | ||
1171 | mp = &((*mp)->next); | ||
1172 | #ifdef MALLOC_EXTRA_SANITY | ||
1173 | if (!*mp) | ||
1174 | wrterror("(ES): Not on queue\n"); | ||
1175 | #endif /* MALLOC_EXTRA_SANITY */ | ||
1176 | } | ||
1177 | *mp = info->next; | ||
1178 | |||
1179 | /* Free the page & the info structure if need be */ | ||
1180 | page_dir[ptr2index(info->page)] = MALLOC_FIRST; | ||
1181 | |||
1182 | /* If the page was mprotected, unprotect it before releasing it */ | ||
1183 | if (info->size == 0) { | ||
1184 | mprotect(info->page, malloc_pagesize, PROT_READ|PROT_WRITE); | ||
1185 | /* Do we have to care if mprotect succeeds here ? */ | ||
1186 | } | ||
1187 | |||
1188 | vp = info->page; /* Order is important ! */ | ||
1189 | if(vp != (void*)info) | ||
1190 | ifree(info); | ||
1191 | ifree(vp); | ||
1192 | } | ||
1193 | |||
1194 | static void | ||
1195 | ifree(ptr) | ||
1196 | void *ptr; | ||
1197 | { | ||
1198 | struct pginfo *info; | ||
1199 | int index; | ||
1200 | |||
1201 | /* This is legal */ | ||
1202 | if (!ptr) | ||
1203 | return; | ||
1204 | |||
1205 | if (!malloc_started) { | ||
1206 | wrtwarning("malloc() has never been called.\n"); | ||
1207 | return; | ||
1208 | } | ||
1209 | |||
1210 | /* If we're already sinking, don't make matters any worse. */ | ||
1211 | if (suicide) | ||
1212 | return; | ||
1213 | |||
1214 | index = ptr2index(ptr); | ||
1215 | |||
1216 | if (index < malloc_pageshift) { | ||
1217 | wrtwarning("junk pointer, too low to make sense.\n"); | ||
1218 | return; | ||
1219 | } | ||
1220 | |||
1221 | if (index > last_index) { | ||
1222 | wrtwarning("junk pointer, too high to make sense.\n"); | ||
1223 | return; | ||
1224 | } | ||
1225 | |||
1226 | info = page_dir[index]; | ||
1227 | |||
1228 | if (info < MALLOC_MAGIC) | ||
1229 | free_pages(ptr, index, info); | ||
1230 | else | ||
1231 | free_bytes(ptr, index, info); | ||
1232 | return; | ||
1233 | } | ||
1234 | |||
1235 | /* | ||
1236 | * These are the public exported interface routines. | ||
1237 | */ | ||
1238 | |||
1239 | static int malloc_active; | ||
1240 | |||
1241 | void * | ||
1242 | malloc(size_t size) | ||
1243 | { | ||
1244 | register void *r; | ||
1245 | |||
1246 | malloc_func = " in malloc():"; | ||
1247 | THREAD_LOCK(); | ||
1248 | if (malloc_active++) { | ||
1249 | wrtwarning("recursive call.\n"); | ||
1250 | malloc_active--; | ||
1251 | THREAD_UNLOCK(); | ||
1252 | return (0); | ||
1253 | } | ||
1254 | r = imalloc(size); | ||
1255 | UTRACE(0, size, r); | ||
1256 | malloc_active--; | ||
1257 | THREAD_UNLOCK(); | ||
1258 | if (malloc_xmalloc && !r) | ||
1259 | wrterror("out of memory.\n"); | ||
1260 | return (r); | ||
1261 | } | ||
1262 | |||
1263 | void | ||
1264 | free(void *ptr) | ||
1265 | { | ||
1266 | malloc_func = " in free():"; | ||
1267 | THREAD_LOCK(); | ||
1268 | if (malloc_active++) { | ||
1269 | wrtwarning("recursive call.\n"); | ||
1270 | malloc_active--; | ||
1271 | THREAD_UNLOCK(); | ||
1272 | return; | ||
1273 | } | ||
1274 | ifree(ptr); | ||
1275 | UTRACE(ptr, 0, 0); | ||
1276 | malloc_active--; | ||
1277 | THREAD_UNLOCK(); | ||
1278 | return; | ||
1279 | } | ||
1280 | |||
1281 | void * | ||
1282 | realloc(void *ptr, size_t size) | ||
1283 | { | ||
1284 | register void *r; | ||
1285 | |||
1286 | malloc_func = " in realloc():"; | ||
1287 | THREAD_LOCK(); | ||
1288 | if (malloc_active++) { | ||
1289 | wrtwarning("recursive call.\n"); | ||
1290 | malloc_active--; | ||
1291 | THREAD_UNLOCK(); | ||
1292 | return (0); | ||
1293 | } | ||
1294 | if (!ptr) { | ||
1295 | r = imalloc(size); | ||
1296 | } else { | ||
1297 | r = irealloc(ptr, size); | ||
1298 | } | ||
1299 | UTRACE(ptr, size, r); | ||
1300 | malloc_active--; | ||
1301 | THREAD_UNLOCK(); | ||
1302 | if (malloc_xmalloc && !r) | ||
1303 | wrterror("out of memory.\n"); | ||
1304 | return (r); | ||
420 | } | 1305 | } |
421 | #endif | ||