xref: /minix/minix/lib/liblwip/dist/src/core/memp.c (revision 9f81acbc)
1 /**
2  * @file
3  * Dynamic pool memory manager
4  *
5  * lwIP has dedicated pools for many structures (netconn, protocol control blocks,
6  * packet buffers, ...). All these pools are managed here.
7  *
8  * @defgroup mempool Memory pools
9  * @ingroup infrastructure
10  * Custom memory pools
11 
12  */
13 
14 /*
15  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
16  * All rights reserved.
17  *
18  * Redistribution and use in source and binary forms, with or without modification,
19  * are permitted provided that the following conditions are met:
20  *
21  * 1. Redistributions of source code must retain the above copyright notice,
22  *    this list of conditions and the following disclaimer.
23  * 2. Redistributions in binary form must reproduce the above copyright notice,
24  *    this list of conditions and the following disclaimer in the documentation
25  *    and/or other materials provided with the distribution.
26  * 3. The name of the author may not be used to endorse or promote products
27  *    derived from this software without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
30  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
31  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
32  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
33  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
34  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
37  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
38  * OF SUCH DAMAGE.
39  *
40  * This file is part of the lwIP TCP/IP stack.
41  *
42  * Author: Adam Dunkels <adam@sics.se>
43  *
44  */
45 
46 #include "lwip/opt.h"
47 
48 #include "lwip/memp.h"
49 #include "lwip/sys.h"
50 #include "lwip/stats.h"
51 
52 #include <string.h>
53 
54 /* Make sure we include everything we need for size calculation required by memp_std.h */
55 #include "lwip/pbuf.h"
56 #include "lwip/raw.h"
57 #include "lwip/udp.h"
58 #include "lwip/tcp.h"
59 #include "lwip/priv/tcp_priv.h"
60 #include "lwip/ip4_frag.h"
61 #include "lwip/netbuf.h"
62 #include "lwip/api.h"
63 #include "lwip/priv/tcpip_priv.h"
64 #include "lwip/priv/api_msg.h"
65 #include "lwip/sockets.h"
66 #include "lwip/priv/sockets_priv.h"
67 #include "lwip/netifapi.h"
68 #include "lwip/etharp.h"
69 #include "lwip/igmp.h"
70 #include "lwip/timeouts.h"
71 /* needed by default MEMP_NUM_SYS_TIMEOUT */
72 #include "netif/ppp/ppp_opts.h"
73 #include "lwip/netdb.h"
74 #include "lwip/dns.h"
75 #include "lwip/priv/nd6_priv.h"
76 #include "lwip/ip6_frag.h"
77 #include "lwip/mld6.h"
78 
79 #define LWIP_MEMPOOL(name,num,size,desc) LWIP_MEMPOOL_DECLARE(name,num,size,desc)
80 #include "lwip/priv/memp_std.h"
81 
82 const struct memp_desc* const memp_pools[MEMP_MAX] = {
83 #define LWIP_MEMPOOL(name,num,size,desc) &memp_ ## name,
84 #include "lwip/priv/memp_std.h"
85 };
86 
87 #ifdef LWIP_HOOK_FILENAME
88 #include LWIP_HOOK_FILENAME
89 #endif
90 
91 #if MEMP_MEM_MALLOC && MEMP_OVERFLOW_CHECK >= 2
92 #undef MEMP_OVERFLOW_CHECK
93 /* MEMP_OVERFLOW_CHECK >= 2 does not work with MEMP_MEM_MALLOC, use 1 instead */
94 #define MEMP_OVERFLOW_CHECK 1
95 #endif
96 
97 #if MEMP_SANITY_CHECK && !MEMP_MEM_MALLOC
98 /**
99  * Check that memp-lists don't form a circle, using "Floyd's cycle-finding algorithm".
100  */
101 static int
102 memp_sanity(const struct memp_desc *desc)
103 {
104   struct memp *t, *h;
105 
106   t = *desc->tab;
107   if (t != NULL) {
108     for (h = t->next; (t != NULL) && (h != NULL); t = t->next,
109       h = ((h->next != NULL) ? h->next->next : NULL)) {
110       if (t == h) {
111         return 0;
112       }
113     }
114   }
115 
116   return 1;
117 }
118 #endif /* MEMP_SANITY_CHECK && !MEMP_MEM_MALLOC */
119 
120 #if MEMP_OVERFLOW_CHECK
121 /**
122  * Check if a memp element was victim of an overflow
123  * (e.g. the restricted area after it has been altered)
124  *
125  * @param p the memp element to check
126  * @param desc the pool p comes from
127  */
128 static void
129 memp_overflow_check_element_overflow(struct memp *p, const struct memp_desc *desc)
130 {
131 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
132   u16_t k;
133   u8_t *m;
134   m = (u8_t*)p + MEMP_SIZE + desc->size;
135   for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
136     if (m[k] != 0xcd) {
137       char errstr[128] = "detected memp overflow in pool ";
138       strcat(errstr, desc->desc);
139       LWIP_ASSERT(errstr, 0);
140     }
141   }
142 #else /* MEMP_SANITY_REGION_AFTER_ALIGNED > 0 */
143   LWIP_UNUSED_ARG(p);
144   LWIP_UNUSED_ARG(desc);
145 #endif /* MEMP_SANITY_REGION_AFTER_ALIGNED > 0 */
146 }
147 
148 /**
149  * Check if a memp element was victim of an underflow
150  * (e.g. the restricted area before it has been altered)
151  *
152  * @param p the memp element to check
153  * @param desc the pool p comes from
154  */
155 static void
156 memp_overflow_check_element_underflow(struct memp *p, const struct memp_desc *desc)
157 {
158 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
159   u16_t k;
160   u8_t *m;
161   m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
162   for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
163     if (m[k] != 0xcd) {
164       char errstr[128] = "detected memp underflow in pool ";
165       strcat(errstr, desc->desc);
166       LWIP_ASSERT(errstr, 0);
167     }
168   }
169 #else /* MEMP_SANITY_REGION_BEFORE_ALIGNED > 0 */
170   LWIP_UNUSED_ARG(p);
171   LWIP_UNUSED_ARG(desc);
172 #endif /* MEMP_SANITY_REGION_BEFORE_ALIGNED > 0 */
173 }
174 
175 /**
176  * Initialize the restricted area of on memp element.
177  */
178 static void
179 memp_overflow_init_element(struct memp *p, const struct memp_desc *desc)
180 {
181 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0 || MEMP_SANITY_REGION_AFTER_ALIGNED > 0
182   u8_t *m;
183 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
184   m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
185   memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
186 #endif
187 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
188   m = (u8_t*)p + MEMP_SIZE + desc->size;
189   memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
190 #endif
191 #else /* MEMP_SANITY_REGION_BEFORE_ALIGNED > 0 || MEMP_SANITY_REGION_AFTER_ALIGNED > 0 */
192   LWIP_UNUSED_ARG(p);
193   LWIP_UNUSED_ARG(desc);
194 #endif /* MEMP_SANITY_REGION_BEFORE_ALIGNED > 0 || MEMP_SANITY_REGION_AFTER_ALIGNED > 0 */
195 }
196 
197 #if MEMP_OVERFLOW_CHECK >= 2
198 /**
199  * Do an overflow check for all elements in every pool.
200  *
201  * @see memp_overflow_check_element for a description of the check
202  */
203 static void
204 memp_overflow_check_all(void)
205 {
206   u16_t i, j;
207   struct memp *p;
208   SYS_ARCH_DECL_PROTECT(old_level);
209   SYS_ARCH_PROTECT(old_level);
210 
211   for (i = 0; i < MEMP_MAX; ++i) {
212     p = (struct memp*)LWIP_MEM_ALIGN(memp_pools[i]->base);
213     for (j = 0; j < memp_pools[i]->num; ++j) {
214       memp_overflow_check_element_overflow(p, memp_pools[i]);
215       memp_overflow_check_element_underflow(p, memp_pools[i]);
216       p = LWIP_ALIGNMENT_CAST(struct memp*, ((u8_t*)p + MEMP_SIZE + memp_pools[i]->size + MEMP_SANITY_REGION_AFTER_ALIGNED));
217     }
218   }
219   SYS_ARCH_UNPROTECT(old_level);
220 }
221 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
222 #endif /* MEMP_OVERFLOW_CHECK */
223 
224 /**
225  * Initialize custom memory pool.
226  * Related functions: memp_malloc_pool, memp_free_pool
227  *
228  * @param desc pool to initialize
229  */
230 void
231 memp_init_pool(const struct memp_desc *desc)
232 {
233 #if MEMP_MEM_MALLOC
234   LWIP_UNUSED_ARG(desc);
235 #else
236   int i;
237   struct memp *memp;
238 
239   *desc->tab = NULL;
240   memp = (struct memp*)LWIP_MEM_ALIGN(desc->base);
241   /* create a linked list of memp elements */
242   for (i = 0; i < desc->num; ++i) {
243     memp->next = *desc->tab;
244     *desc->tab = memp;
245 #if MEMP_OVERFLOW_CHECK
246     memp_overflow_init_element(memp, desc);
247 #endif /* MEMP_OVERFLOW_CHECK */
248    /* cast through void* to get rid of alignment warnings */
249    memp = (struct memp *)(void *)((u8_t *)memp + MEMP_SIZE + desc->size
250 #if MEMP_OVERFLOW_CHECK
251       + MEMP_SANITY_REGION_AFTER_ALIGNED
252 #endif
253     );
254   }
255 #if MEMP_STATS
256   desc->stats->avail = desc->num;
257 #endif /* MEMP_STATS */
258 #endif /* !MEMP_MEM_MALLOC */
259 
260 #if MEMP_STATS && (defined(LWIP_DEBUG) || LWIP_STATS_DISPLAY)
261   desc->stats->name  = desc->desc;
262 #endif /* MEMP_STATS && (defined(LWIP_DEBUG) || LWIP_STATS_DISPLAY) */
263 }
264 
265 /**
266  * Initializes lwIP built-in pools.
267  * Related functions: memp_malloc, memp_free
268  *
269  * Carves out memp_memory into linked lists for each pool-type.
270  */
271 void
272 memp_init(void)
273 {
274   u16_t i;
275 
276   /* for every pool: */
277   for (i = 0; i < LWIP_ARRAYSIZE(memp_pools); i++) {
278     memp_init_pool(memp_pools[i]);
279 
280 #if LWIP_STATS && MEMP_STATS
281     lwip_stats.memp[i] = memp_pools[i]->stats;
282 #endif
283   }
284 
285 #if MEMP_OVERFLOW_CHECK >= 2
286   /* check everything a first time to see if it worked */
287   memp_overflow_check_all();
288 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
289 }
290 
291 static void*
292 #if !MEMP_OVERFLOW_CHECK
293 do_memp_malloc_pool(const struct memp_desc *desc)
294 #else
295 do_memp_malloc_pool_fn(const struct memp_desc *desc, const char* file, const int line)
296 #endif
297 {
298   struct memp *memp;
299   SYS_ARCH_DECL_PROTECT(old_level);
300 
301 #if MEMP_MEM_MALLOC
302   memp = (struct memp *)mem_malloc(MEMP_SIZE + MEMP_ALIGN_SIZE(desc->size));
303   SYS_ARCH_PROTECT(old_level);
304 #else /* MEMP_MEM_MALLOC */
305   SYS_ARCH_PROTECT(old_level);
306 
307   memp = *desc->tab;
308 #endif /* MEMP_MEM_MALLOC */
309 
310   if (memp != NULL) {
311 #if !MEMP_MEM_MALLOC
312 #if MEMP_OVERFLOW_CHECK == 1
313     memp_overflow_check_element_overflow(memp, desc);
314     memp_overflow_check_element_underflow(memp, desc);
315 #endif /* MEMP_OVERFLOW_CHECK */
316 
317     *desc->tab = memp->next;
318 #if MEMP_OVERFLOW_CHECK
319     memp->next = NULL;
320 #endif /* MEMP_OVERFLOW_CHECK */
321 #endif /* !MEMP_MEM_MALLOC */
322 #if MEMP_OVERFLOW_CHECK
323     memp->file = file;
324     memp->line = line;
325 #if MEMP_MEM_MALLOC
326     memp_overflow_init_element(memp, desc);
327 #endif /* MEMP_MEM_MALLOC */
328 #endif /* MEMP_OVERFLOW_CHECK */
329     LWIP_ASSERT("memp_malloc: memp properly aligned",
330                 ((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
331 #if MEMP_STATS
332     desc->stats->used++;
333     if (desc->stats->used > desc->stats->max) {
334       desc->stats->max = desc->stats->used;
335     }
336 #endif
337     SYS_ARCH_UNPROTECT(old_level);
338     /* cast through u8_t* to get rid of alignment warnings */
339     return ((u8_t*)memp + MEMP_SIZE);
340   } else {
341     LWIP_DEBUGF(MEMP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("memp_malloc: out of memory in pool %s\n", desc->desc));
342 #if MEMP_STATS
343     desc->stats->err++;
344 #endif
345   }
346 
347   SYS_ARCH_UNPROTECT(old_level);
348   return NULL;
349 }
350 
351 /**
352  * Get an element from a custom pool.
353  *
354  * @param desc the pool to get an element from
355  *
356  * @return a pointer to the allocated memory or a NULL pointer on error
357  */
358 void *
359 #if !MEMP_OVERFLOW_CHECK
360 memp_malloc_pool(const struct memp_desc *desc)
361 #else
362 memp_malloc_pool_fn(const struct memp_desc *desc, const char* file, const int line)
363 #endif
364 {
365   LWIP_ASSERT("invalid pool desc", desc != NULL);
366   if (desc == NULL) {
367     return NULL;
368   }
369 
370 #if !MEMP_OVERFLOW_CHECK
371   return do_memp_malloc_pool(desc);
372 #else
373   return do_memp_malloc_pool_fn(desc, file, line);
374 #endif
375 }
376 
377 /**
378  * Get an element from a specific pool.
379  *
380  * @param type the pool to get an element from
381  *
382  * @return a pointer to the allocated memory or a NULL pointer on error
383  */
384 void *
385 #if !MEMP_OVERFLOW_CHECK
386 memp_malloc(memp_t type)
387 #else
388 memp_malloc_fn(memp_t type, const char* file, const int line)
389 #endif
390 {
391   void *memp;
392   LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
393 
394 #if MEMP_OVERFLOW_CHECK >= 2
395   memp_overflow_check_all();
396 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
397 
398 #if !MEMP_OVERFLOW_CHECK
399   memp = do_memp_malloc_pool(memp_pools[type]);
400 #else
401   memp = do_memp_malloc_pool_fn(memp_pools[type], file, line);
402 #endif
403 
404   return memp;
405 }
406 
407 static void
408 do_memp_free_pool(const struct memp_desc* desc, void *mem)
409 {
410   struct memp *memp;
411   SYS_ARCH_DECL_PROTECT(old_level);
412 
413   LWIP_ASSERT("memp_free: mem properly aligned",
414                 ((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
415 
416   /* cast through void* to get rid of alignment warnings */
417   memp = (struct memp *)(void *)((u8_t*)mem - MEMP_SIZE);
418 
419   SYS_ARCH_PROTECT(old_level);
420 
421 #if MEMP_OVERFLOW_CHECK == 1
422   memp_overflow_check_element_overflow(memp, desc);
423   memp_overflow_check_element_underflow(memp, desc);
424 #endif /* MEMP_OVERFLOW_CHECK */
425 
426 #if MEMP_STATS
427   desc->stats->used--;
428 #endif
429 
430 #if MEMP_MEM_MALLOC
431   LWIP_UNUSED_ARG(desc);
432   SYS_ARCH_UNPROTECT(old_level);
433   mem_free(memp);
434 #else /* MEMP_MEM_MALLOC */
435   memp->next = *desc->tab;
436   *desc->tab = memp;
437 
438 #if MEMP_SANITY_CHECK
439   LWIP_ASSERT("memp sanity", memp_sanity(desc));
440 #endif /* MEMP_SANITY_CHECK */
441 
442   SYS_ARCH_UNPROTECT(old_level);
443 #endif /* !MEMP_MEM_MALLOC */
444 }
445 
446 /**
447  * Put a custom pool element back into its pool.
448  *
449  * @param desc the pool where to put mem
450  * @param mem the memp element to free
451  */
452 void
453 memp_free_pool(const struct memp_desc* desc, void *mem)
454 {
455   LWIP_ASSERT("invalid pool desc", desc != NULL);
456   if ((desc == NULL) || (mem == NULL)) {
457     return;
458   }
459 
460   do_memp_free_pool(desc, mem);
461 }
462 
463 /**
464  * Put an element back into its pool.
465  *
466  * @param type the pool where to put mem
467  * @param mem the memp element to free
468  */
469 void
470 memp_free(memp_t type, void *mem)
471 {
472 #ifdef LWIP_HOOK_MEMP_AVAILABLE
473   struct memp *old_first;
474 #endif
475 
476   LWIP_ERROR("memp_free: type < MEMP_MAX", (type < MEMP_MAX), return;);
477 
478   if (mem == NULL) {
479     return;
480   }
481 
482 #if MEMP_OVERFLOW_CHECK >= 2
483   memp_overflow_check_all();
484 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
485 
486 #ifdef LWIP_HOOK_MEMP_AVAILABLE
487   old_first = *memp_pools[type]->tab;
488 #endif
489 
490   do_memp_free_pool(memp_pools[type], mem);
491 
492 #ifdef LWIP_HOOK_MEMP_AVAILABLE
493   if (old_first == NULL) {
494     LWIP_HOOK_MEMP_AVAILABLE(type);
495   }
496 #endif
497 }
498