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
180 */
181 static int
memp_sanity(void)182 memp_sanity(void)
183 {
184 s16_t i, c;
185 struct memp *m, *n;
186
187 for (i = 0; i < MEMP_MAX; i++) {
188 for (m = memp_tab[i]; m != NULL; m = m->next) {
189 c = 1;
190 for (n = memp_tab[i]; n != NULL; n = n->next) {
191 if (n == m && --c < 0) {
192 return 0;
193 }
194 }
195 }
196 }
197 return 1;
198 }
199 #endif /* MEMP_SANITY_CHECK*/
200 #if MEMP_OVERFLOW_CHECK
201 #if defined(LWIP_DEBUG) && MEMP_STATS
202 static const char * memp_overflow_names[] = {
203 #define LWIP_MEMPOOL(name,num,size,desc) "/"desc,
204 #include "lwip/memp_std.h"
205 };
206 #endif
207
208 /**
209 * Check if a memp element was victim of an overflow
210 * (e.g. the restricted area after it has been altered)
211 *
212 * @param p the memp element to check
213 * @param memp_type the pool p comes from
214 */
215 static void
memp_overflow_check_element_overflow(struct memp * p,u16_t memp_type)216 memp_overflow_check_element_overflow(struct memp *p, u16_t memp_type)
217 {
218 u16_t k;
219 u8_t *m;
220 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
221 m = (u8_t*)p + MEMP_SIZE + memp_sizes[memp_type];
222 for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
223 if (m[k] != 0xcd) {
224 char errstr[128] = "detected memp overflow in pool ";
225 char digit[] = "0";
226 if(memp_type >= 10) {
227 digit[0] = '0' + (memp_type/10);
228 strcat(errstr, digit);
229 }
230 digit[0] = '0' + (memp_type%10);
231 strcat(errstr, digit);
232 #if defined(LWIP_DEBUG) && MEMP_STATS
233 strcat(errstr, memp_overflow_names[memp_type]);
234 #endif
235 LWIP_ASSERT(errstr, 0);
236 }
237 }
238 #endif
239 }
240
241 /**
242 * Check if a memp element was victim of an underflow
243 * (e.g. the restricted area before it has been altered)
244 *
245 * @param p the memp element to check
246 * @param memp_type the pool p comes from
247 */
248 static void
memp_overflow_check_element_underflow(struct memp * p,u16_t memp_type)249 memp_overflow_check_element_underflow(struct memp *p, u16_t memp_type)
250 {
251 u16_t k;
252 u8_t *m;
253 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
254 m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
255 for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
256 if (m[k] != 0xcd) {
257 char errstr[128] = "detected memp underflow in pool ";
258 char digit[] = "0";
259 if(memp_type >= 10) {
260 digit[0] = '0' + (memp_type/10);
261 strcat(errstr, digit);
262 }
263 digit[0] = '0' + (memp_type%10);
264 strcat(errstr, digit);
265 #if defined(LWIP_DEBUG) && MEMP_STATS
266 strcat(errstr, memp_overflow_names[memp_type]);
267 #endif
268 LWIP_ASSERT(errstr, 0);
269 }
270 }
271 #endif
272 }
273
274 /**
275 * Do an overflow check for all elements in every pool.
276 *
277 * @see memp_overflow_check_element for a description of the check
278 */
279 static void
memp_overflow_check_all(void)280 memp_overflow_check_all(void)
281 {
282 u16_t i, j;
283 struct memp *p;
284
285 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
286 for (i = 0; i < MEMP_MAX; ++i) {
287 p = p;
288 for (j = 0; j < memp_num[i]; ++j) {
289 memp_overflow_check_element_overflow(p, i);
290 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
291 }
292 }
293 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
294 for (i = 0; i < MEMP_MAX; ++i) {
295 p = p;
296 for (j = 0; j < memp_num[i]; ++j) {
297 memp_overflow_check_element_underflow(p, i);
298 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
299 }
300 }
301 }
302
303 /**
304 * Initialize the restricted areas of all memp elements in every pool.
305 */
306 static void
memp_overflow_init(void)307 memp_overflow_init(void)
308 {
309 u16_t i, j;
310 struct memp *p;
311 u8_t *m;
312
313 p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
314 for (i = 0; i < MEMP_MAX; ++i) {
315 p = p;
316 for (j = 0; j < memp_num[i]; ++j) {
317 #if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
318 m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
319 memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
320 #endif
321 #if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
322 m = (u8_t*)p + MEMP_SIZE + memp_sizes[i];
323 memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
324 #endif
325 p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
326 }
327 }
328 }
329 #endif /* MEMP_OVERFLOW_CHECK */
330
331 /**
332 * Initialize this module.
333 *
334 * Carves out memp_memory into linked lists for each pool-type.
335 */
336 void
memp_init(void)337 memp_init(void)
338 {
339 struct memp *memp;
340 u16_t i, j;
341
342 for (i = 0; i < MEMP_MAX; ++i) {
343 MEMP_STATS_AVAIL(used, i, 0);
344 MEMP_STATS_AVAIL(max, i, 0);
345 MEMP_STATS_AVAIL(err, i, 0);
346 MEMP_STATS_AVAIL(avail, i, memp_num[i]);
347 }
348
349 #if !MEMP_SEPARATE_POOLS
350 memp = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
351 #endif /* !MEMP_SEPARATE_POOLS */
352 /* for every pool: */
353 for (i = 0; i < MEMP_MAX; ++i) {
354 memp_tab[i] = NULL;
355 #if MEMP_SEPARATE_POOLS
356 memp = (struct memp*)memp_bases[i];
357 #endif /* MEMP_SEPARATE_POOLS */
358 /* create a linked list of memp elements */
359 for (j = 0; j < memp_num[i]; ++j) {
360 memp->next = memp_tab[i];
361 memp_tab[i] = memp;
362 memp = (struct memp *)(void *)((u8_t *)memp + MEMP_SIZE + memp_sizes[i]
363 #if MEMP_OVERFLOW_CHECK
364 + MEMP_SANITY_REGION_AFTER_ALIGNED
365 #endif
366 );
367 }
368 }
369 #if MEMP_OVERFLOW_CHECK
370 memp_overflow_init();
371 /* check everything a first time to see if it worked */
372 memp_overflow_check_all();
373 #endif /* MEMP_OVERFLOW_CHECK */
374 }
375
376 /**
377 * Get an element from a specific pool.
378 *
379 * @param type the pool to get an element from
380 *
381 * the debug version has two more parameters:
382 * @param file file name calling this function
383 * @param line number of line where this function is called
384 *
385 * @return a pointer to the allocated memory or a NULL pointer on error
386 */
387 void *
388 #if !MEMP_OVERFLOW_CHECK
memp_malloc(memp_t type)389 memp_malloc(memp_t type)
390 #else
391 memp_malloc_fn(memp_t type, const char* file, const int line)
392 #endif
393 {
394 struct memp *memp;
395 SYS_ARCH_DECL_PROTECT(old_level);
396
397 LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
398
399 SYS_ARCH_PROTECT(old_level);
400 #if MEMP_OVERFLOW_CHECK >= 2
401 memp_overflow_check_all();
402 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
403
404 memp = memp_tab[type];
405
406 if (memp != NULL) {
407 memp_tab[type] = memp->next;
408 #if MEMP_OVERFLOW_CHECK
409 memp->next = NULL;
410 memp->file = file;
411 memp->line = line;
412 #endif /* MEMP_OVERFLOW_CHECK */
413 MEMP_STATS_INC_USED(used, type);
414 LWIP_ASSERT("memp_malloc: memp properly aligned",
415 ((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
416 memp = (struct memp*)(void *)((u8_t*)memp + MEMP_SIZE);
417 } else {
418 LWIP_DEBUGF(MEMP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("memp_malloc: out of memory in pool %s\n", memp_desc[type]));
419 MEMP_STATS_INC(err, type);
420 }
421
422 SYS_ARCH_UNPROTECT(old_level);
423
424 return memp;
425 }
426
427 /**
428 * Put an element back into its pool.
429 *
430 * @param type the pool where to put mem
431 * @param mem the memp element to free
432 */
433 void
memp_free(memp_t type,void * mem)434 memp_free(memp_t type, void *mem)
435 {
436 struct memp *memp;
437 SYS_ARCH_DECL_PROTECT(old_level);
438
439 if (mem == NULL) {
440 return;
441 }
442 LWIP_ASSERT("memp_free: mem properly aligned",
443 ((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
444
445 memp = (struct memp *)(void *)((u8_t*)mem - MEMP_SIZE);
446
447 SYS_ARCH_PROTECT(old_level);
448 #if MEMP_OVERFLOW_CHECK
449 #if MEMP_OVERFLOW_CHECK >= 2
450 memp_overflow_check_all();
451 #else
452 memp_overflow_check_element_overflow(memp, type);
453 memp_overflow_check_element_underflow(memp, type);
454 #endif /* MEMP_OVERFLOW_CHECK >= 2 */
455 #endif /* MEMP_OVERFLOW_CHECK */
456
457 MEMP_STATS_DEC(used, type);
458
459 memp->next = memp_tab[type];
460 memp_tab[type] = memp;
461
462 #if MEMP_SANITY_CHECK
463 LWIP_ASSERT("memp sanity", memp_sanity());
464 #endif /* MEMP_SANITY_CHECK */
465
466 SYS_ARCH_UNPROTECT(old_level);
467 }
468
469 #endif /* MEMP_MEM_MALLOC */
470