void mm_initialize(FAR struct mm_heap_s *heap, FAR void *heapstart, size_t heapsize) { int i; mlldbg("Heap: start=%p size=%u\n", heapstart, heapsize); /* The following two lines have cause problems for some older ZiLog * compilers in the past (but not the more recent). Life is easier if we * just the suppress them altogther for those tools. */ #ifndef __ZILOG__ CHECK_ALLOCNODE_SIZE; CHECK_FREENODE_SIZE; #endif /* Set up global variables */ heap->mm_heapsize = 0; #if CONFIG_MM_REGIONS > 1 heap->mm_nregions = 0; #endif /* Initialize the node array */ memset(heap->mm_nodelist, 0, sizeof(struct mm_freenode_s) * MM_NNODES); for (i = 1; i < MM_NNODES; i++) { heap->mm_nodelist[i-1].flink = &heap->mm_nodelist[i]; heap->mm_nodelist[i].blink = &heap->mm_nodelist[i-1]; } /* Initialize the malloc semaphore to one (to support one-at- * a-time access to private data sets). */ mm_seminitialize(heap); /* Add the initial region of memory to the heap */ mm_addregion(heap, heapstart, heapsize); }
void mm_addregion(FAR void *heapstart, size_t heapsize) { FAR struct mm_freenode_s *node; uintptr_t heapbase; uintptr_t heapend; #if CONFIG_MM_REGIONS > 1 int IDX = g_nregions; #else # define IDX 0 #endif /* If the MCU handles wide addresses but the memory manager * is configured for a small heap, then verify that the caller * not doing something crazy. */ #if defined(CONFIG_MM_SMALL) && !defined(CONFIG_SMALL_MEMORY) DEBUGASSERT(heapsize <= MMSIZE_MAX+1); #endif /* Adjust the provide heap start and size so that they are * both aligned with the MM_MIN_CHUNK size. */ heapbase = MM_ALIGN_UP((uintptr_t)heapstart); heapend = MM_ALIGN_DOWN((uintptr_t)heapstart + (uintptr_t)heapsize); heapsize = heapend - heapbase; mlldbg("Region %d: base=%p size=%u\n", IDX+1, heapstart, heapsize); /* Add the size of this region to the total size of the heap */ g_heapsize += heapsize; /* Create two "allocated" guard nodes at the beginning and end of * the heap. These only serve to keep us from allocating outside * of the heap. * * And create one free node between the guard nodes that contains * all available memory. */ g_heapstart[IDX] = (FAR struct mm_allocnode_s *)heapbase; g_heapstart[IDX]->size = SIZEOF_MM_ALLOCNODE; g_heapstart[IDX]->preceding = MM_ALLOC_BIT; node = (FAR struct mm_freenode_s *)(heapbase + SIZEOF_MM_ALLOCNODE); node->size = heapsize - 2*SIZEOF_MM_ALLOCNODE; node->preceding = SIZEOF_MM_ALLOCNODE; g_heapend[IDX] = (FAR struct mm_allocnode_s *)(heapend - SIZEOF_MM_ALLOCNODE); g_heapend[IDX]->size = SIZEOF_MM_ALLOCNODE; g_heapend[IDX]->preceding = node->size | MM_ALLOC_BIT; #undef IDX #if CONFIG_MM_REGIONS > 1 g_nregions++; #endif /* Add the single, large free node to the nodelist */ mm_addfreechunk(node); }