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
9 /*
10 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without modification,
14 * are permitted provided that the following conditions are met:
15 *
16 * 1. Redistributions of source code must retain the above copyright notice,
17 * this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright notice,
19 * this list of conditions and the following disclaimer in the documentation
20 * and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
27 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
28 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
29 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
32 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
33 * OF SUCH DAMAGE.
34 *
35 * This file is part of the lwIP TCP/IP stack.
36 *
37 * Author: Adam Dunkels <adam@sics.se>
38 *
39 */
40
41 #include "lwip/opt.h"
42
43 #include "lwip/memp.h"
44 #include "lwip/pbuf.h"
45 #include "lwip/udp.h"
46 #include "lwip/raw.h"
47 #include "lwip/tcp_impl.h"
48 #include "lwip/igmp.h"
49 #include "lwip/api.h"
50 #include "lwip/api_msg.h"
51 #include "lwip/tcpip.h"
52 #include "lwip/sys.h"
53 #include "lwip/timers.h"
54 #include "lwip/stats.h"
55 #include "netif/etharp.h"
56 #include "lwip/ip_frag.h"
57 #include "lwip/snmp_structs.h"
58 #include "lwip/snmp_msg.h"
59 #include "lwip/dns.h"
60 #include "netif/ppp_oe.h"
61
62 #include <string.h>
63
64 #if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
65
66 struct memp {
67 struct memp *next;
68 #if MEMP_OVERFLOW_CHECK
69 const char *file;
70 int line;
71 #endif /* MEMP_OVERFLOW_CHECK */
72 };
73
74 #if MEMP_OVERFLOW_CHECK
75 /* if MEMP_OVERFLOW_CHECK is turned on, we reserve some bytes at the beginning
76 * and at the end of each element, initialize them as 0xcd and check
77 * them later. */
78 /* If MEMP_OVERFLOW_CHECK is >= 2, on every call to memp_malloc or memp_free,
79 * every single element in each pool is checked!
80 * This is VERY SLOW but also very helpful. */
81 /* MEMP_SANITY_REGION_BEFORE and MEMP_SANITY_REGION_AFTER can be overridden in
82 * lwipopts.h to change the amount reserved for checking. */
83 #ifndef MEMP_SANITY_REGION_BEFORE
84 #define MEMP_SANITY_REGION_BEFORE 16
85 #endif /* MEMP_SANITY_REGION_BEFORE*/
86 #if MEMP_SANITY_REGION_BEFORE > 0
87 #define MEMP_SANITY_REGION_BEFORE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_BEFORE)
88 #else
89 #define MEMP_SANITY_REGION_BEFORE_ALIGNED 0
90 #endif /* MEMP_SANITY_REGION_BEFORE*/
91 #ifndef MEMP_SANITY_REGION_AFTER
92 #define MEMP_SANITY_REGION_AFTER 16
93 #endif /* MEMP_SANITY_REGION_AFTER*/
94 #if MEMP_SANITY_REGION_AFTER > 0
95 #define MEMP_SANITY_REGION_AFTER_ALIGNED LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_AFTER)
96 #else
97 #define MEMP_SANITY_REGION_AFTER_ALIGNED 0
98 #endif /* MEMP_SANITY_REGION_AFTER*/
99
100 /* MEMP_SIZE: save space for struct memp and for sanity check */
101 #define MEMP_SIZE (LWIP_MEM_ALIGN_SIZE(sizeof(struct memp)) + MEMP_SANITY_REGION_BEFORE_ALIGNED)
102 #define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x) + MEMP_SANITY_REGION_AFTER_ALIGNED)
103
104 #else /* MEMP_OVERFLOW_CHECK */
105
106 /* No sanity checks
107 * We don't need to preserve the struct memp while not allocated, so we
108 * can save a little space and set MEMP_SIZE to 0.
109 */
110 #define MEMP_SIZE 0
111 #define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
112
113 #endif /* MEMP_OVERFLOW_CHECK */
114
115 /** This array holds the first free element of each pool.
116 * Elements form a linked list. */
117 static struct memp *memp_tab[MEMP_MAX];
118
119 #else /* MEMP_MEM_MALLOC */
120
121 #define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
122
123 #endif /* MEMP_MEM_MALLOC */
124
125 /** This array holds the element sizes of each pool. */
126 #if !MEM_USE_POOLS && !MEMP_MEM_MALLOC
127 static
128 #endif
129 const u16_t memp_sizes[MEMP_MAX] = {
130 #define LWIP_MEMPOOL(name,num,size,desc) LWIP_MEM_ALIGN_SIZE(size),
131 #include "lwip/memp_std.h"
132 };
133
134 #if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
135
136 /** This array holds the number of elements in each pool. */
137 static const u16_t memp_num[MEMP_MAX] = {
138 #define LWIP_MEMPOOL(name,num,size,desc) (num),
139 #include "lwip/memp_std.h"
140 };
141
142 /** This array holds a textual description of each pool. */
143 #ifdef LWIP_DEBUG
144 static const char *memp_desc[MEMP_MAX] = {
145 #define LWIP_MEMPOOL(name,num,size,desc) (desc),
146 #include "lwip/memp_std.h"
147 };
148 #endif /* LWIP_DEBUG */
149
150 #if MEMP_SEPARATE_POOLS
151
152 /** This creates each memory pool. These are named memp_memory_XXX_base (where
153 * XXX is the name of the pool defined in memp_std.h).
154 * To relocate a pool, declare it as extern in cc.h. Example for GCC:
155 * extern u8_t __attribute__((section(".onchip_mem"))) memp_memory_UDP_PCB_base[];
156 */
157 #define LWIP_MEMPOOL(name,num,size,desc) u8_t memp_memory_ ## name ## _base \
158 [((num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size)))];
159 #include "lwip/memp_std.h"
160
161 /** This array holds the base of each memory pool. */
162 static u8_t *const memp_bases[] = {
163 #define LWIP_MEMPOOL(name,num,size,desc) memp_memory_ ## name ## _base,
164 #include "lwip/memp_std.h"
165 };
166
167 #else /* MEMP_SEPARATE_POOLS */
168
169 /** This is the actual memory used by the pools (all pools in one big block). */
170 static u8_t memp_memory[MEM_ALIGNMENT - 1
171 #define LWIP_MEMPOOL(name,num,size,desc) + ( (num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size) ) )
172 #include "lwip/memp_std.h"
173 ];
174
175 #endif /* MEMP_SEPARATE_POOLS */
176
177 #if MEMP_SANITY_CHECK
178 /**
179 * Check that memp-lists don't form a circle, using "Floyd's cycle-finding algorithm".
180 */
181 static int
memp_sanity(void)182 memp_sanity(void)
183 {
184 s16_t i;
185 struct memp *t, *h;
186
187 for (i = 0; i < MEMP_MAX; i++) {
188 t = memp_tab[i];
189 if(t != NULL) {
190 for (h = t->next; (t != NULL) && (h != NULL); t = t->next,
191 h = (((h->next != NULL) && (h->next->next != NULL)) ? h->next->next : NULL)) {
192 if (t == h) {
193 return 0;
194 }
195 }
196 }
197 }
198 return 1;
199 }
200 #endif /* MEMP_SANITY_CHECK*/
201 #if MEMP_OVERFLOW_CHECK
202 #if defined(LWIP_DEBUG) && MEMP_STATS
203 static const char * memp_overflow_names[] = {
204 #define LWIP_MEMPOOL(name,num,size,desc) "/"desc,
205 #include "lwip/memp_std.h"
206 };
207 #endif
208
209 /**
210 * Check if a memp element was victim of an overflow
211 * (e.g. the restricted area after it has been altered)
212 *
213 * @param p the memp element to check
214 * @param memp_type the pool p comes from
215 */
216 static void
memp_overflow_check_element_overflow(struct memp * p,u16_t memp_type)217 memp_overflow_check_element_overflow(struct memp *p, u16_t memp_type)
218 {
219 u16_t k;
220 u8_t *m;
221 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
222 m = (u8_t*)p + MEMP_SIZE + memp_sizes[memp_type];
223 for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
224 if (m[k] != 0xcd) {
225 char errstr[128] = "detected memp overflow in pool ";
226 char digit[] = "0";
227 if(memp_type >= 10) {
228 digit[0] = '0' + (memp_type/10);
229 strcat(errstr, digit);
230 }
231 digit[0] = '0' + (memp_type%10);
232 strcat(errstr, digit);
233 #if defined(LWIP_DEBUG) && MEMP_STATS
234 strcat(errstr, memp_overflow_names[memp_type]);
235 #endif
236 LWIP_ASSERT(errstr, 0);
237 }
238 }
239 #endif
240 }
241
242 /**
243 * Check if a memp element was victim of an underflow
244 * (e.g. the restricted area before it has been altered)
245 *
246 * @param p the memp element to check
247 * @param memp_type the pool p comes from
248 */
249 static void
memp_overflow_check_element_underflow(struct memp * p,u16_t memp_type)250 memp_overflow_check_element_underflow(struct memp *p, u16_t memp_type)
251 {
252 u16_t k;
253 u8_t *m;
254 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
255 m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
256 for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
257 if (m[k] != 0xcd) {
258 char errstr[128] = "detected memp underflow in pool ";
259 char digit[] = "0";
260 if(memp_type >= 10) {
261 digit[0] = '0' + (memp_type/10);
262 strcat(errstr, digit);
263 }
264 digit[0] = '0' + (memp_type%10);
265 strcat(errstr, digit);
266 #if defined(LWIP_DEBUG) && MEMP_STATS
267 strcat(errstr, memp_overflow_names[memp_type]);
268 #endif
269 LWIP_ASSERT(errstr, 0);
270 }
271 }
272 #endif
273 }
274
275 /**
276 * Do an overflow check for all elements in every pool.
277 *
278 * @see memp_overflow_check_element for a description of the check
279 */
280 static void
memp_overflow_check_all(void)281 memp_overflow_check_all(void)
282 {
283 u16_t i, j;
284 struct memp *p;
285
286 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
287 for (i = 0; i < MEMP_MAX; ++i) {
288 p = p;
289 for (j = 0; j < memp_num[i]; ++j) {
290 memp_overflow_check_element_overflow(p, i);
291 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
292 }
293 }
294 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
295 for (i = 0; i < MEMP_MAX; ++i) {
296 p = p;
297 for (j = 0; j < memp_num[i]; ++j) {
298 memp_overflow_check_element_underflow(p, i);
299 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
300 }
301 }
302 }
303
304 /**
305 * Initialize the restricted areas of all memp elements in every pool.
306 */
307 static void
memp_overflow_init(void)308 memp_overflow_init(void)
309 {
310 u16_t i, j;
311 struct memp *p;
312 u8_t *m;
313
314 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
315 for (i = 0; i < MEMP_MAX; ++i) {
316 p = p;
317 for (j = 0; j < memp_num[i]; ++j) {
318 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
319 m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
320 memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
321 #endif
322 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
323 m = (u8_t*)p + MEMP_SIZE + memp_sizes[i];
324 memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
325 #endif
326 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
327 }
328 }
329 }
330 #endif /* MEMP_OVERFLOW_CHECK */
331
332 /**
333 * Initialize this module.
334 *
335 * Carves out memp_memory into linked lists for each pool-type.
336 */
337 void
memp_init(void)338 memp_init(void)
339 {
340 struct memp *memp;
341 u16_t i, j;
342
343 for (i = 0; i < MEMP_MAX; ++i) {
344 MEMP_STATS_AVAIL(used, i, 0);
345 MEMP_STATS_AVAIL(max, i, 0);
346 MEMP_STATS_AVAIL(err, i, 0);
347 MEMP_STATS_AVAIL(avail, i, memp_num[i]);
348 }
349
350 #if !MEMP_SEPARATE_POOLS
351 memp = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
352 #endif /* !MEMP_SEPARATE_POOLS */
353 /* for every pool: */
354 for (i = 0; i < MEMP_MAX; ++i) {
355 memp_tab[i] = NULL;
356 #if MEMP_SEPARATE_POOLS
357 memp = (struct memp*)memp_bases[i];
358 #endif /* MEMP_SEPARATE_POOLS */
359 /* create a linked list of memp elements */
360 for (j = 0; j < memp_num[i]; ++j) {
361 memp->next = memp_tab[i];
362 memp_tab[i] = memp;
363 memp = (struct memp *)(void *)((u8_t *)memp + MEMP_SIZE + memp_sizes[i]
364 #if MEMP_OVERFLOW_CHECK
365 + MEMP_SANITY_REGION_AFTER_ALIGNED
366 #endif
367 );
368 }
369 }
370 #if MEMP_OVERFLOW_CHECK
371 memp_overflow_init();
372 /* check everything a first time to see if it worked */
373 memp_overflow_check_all();
374 #endif /* MEMP_OVERFLOW_CHECK */
375 }
376
377 /**
378 * Get an element from a specific pool.
379 *
380 * @param type the pool to get an element from
381 *
382 * the debug version has two more parameters:
383 * @param file file name calling this function
384 * @param line number of line where this function is called
385 *
386 * @return a pointer to the allocated memory or a NULL pointer on error
387 */
388 void *
389 #if !MEMP_OVERFLOW_CHECK
memp_malloc(memp_t type)390 memp_malloc(memp_t type)
391 #else
392 memp_malloc_fn(memp_t type, const char* file, const int line)
393 #endif
394 {
395 struct memp *memp;
396 SYS_ARCH_DECL_PROTECT(old_level);
397
398 LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
399
400 SYS_ARCH_PROTECT(old_level);
401 #if MEMP_OVERFLOW_CHECK >= 2
402 memp_overflow_check_all();
403 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
404
405 memp = memp_tab[type];
406
407 if (memp != NULL) {
408 memp_tab[type] = memp->next;
409 #if MEMP_OVERFLOW_CHECK
410 memp->next = NULL;
411 memp->file = file;
412 memp->line = line;
413 #endif /* MEMP_OVERFLOW_CHECK */
414 MEMP_STATS_INC_USED(used, type);
415 LWIP_ASSERT("memp_malloc: memp properly aligned",
416 ((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
417 memp = (struct memp*)(void *)((u8_t*)memp + MEMP_SIZE);
418 } else {
419 LWIP_DEBUGF(MEMP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("memp_malloc: out of memory in pool %s\n", memp_desc[type]));
420 MEMP_STATS_INC(err, type);
421 }
422
423 SYS_ARCH_UNPROTECT(old_level);
424
425 return memp;
426 }
427
428 /**
429 * Put an element back into its pool.
430 *
431 * @param type the pool where to put mem
432 * @param mem the memp element to free
433 */
434 void
memp_free(memp_t type,void * mem)435 memp_free(memp_t type, void *mem)
436 {
437 struct memp *memp;
438 SYS_ARCH_DECL_PROTECT(old_level);
439
440 if (mem == NULL) {
441 return;
442 }
443 LWIP_ASSERT("memp_free: mem properly aligned",
444 ((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
445
446 memp = (struct memp *)(void *)((u8_t*)mem - MEMP_SIZE);
447
448 SYS_ARCH_PROTECT(old_level);
449 #if MEMP_OVERFLOW_CHECK
450 #if MEMP_OVERFLOW_CHECK >= 2
451 memp_overflow_check_all();
452 #else
453 memp_overflow_check_element_overflow(memp, type);
454 memp_overflow_check_element_underflow(memp, type);
455 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
456 #endif /* MEMP_OVERFLOW_CHECK */
457
458 MEMP_STATS_DEC(used, type);
459
460 memp->next = memp_tab[type];
461 memp_tab[type] = memp;
462
463 #if MEMP_SANITY_CHECK
464 LWIP_ASSERT("memp sanity", memp_sanity());
465 #endif /* MEMP_SANITY_CHECK */
466
467 SYS_ARCH_UNPROTECT(old_level);
468 }
469
470 #endif /* MEMP_MEM_MALLOC */
471