1 /* 2 * malloc.h 3 * 4 * Internals for the memory allocator 5 */ 6 7 #include <stdint.h> 8 #include <stddef.h> 9 #include "core.h" 10 #include "thread.h" 11 12 extern struct semaphore __malloc_semaphore; 13 14 /* 15 * This is a temporary hack. In Syslinux 5 this will be a pointer to 16 * the owner module. 17 */ 18 typedef size_t malloc_tag_t; 19 enum malloc_owner { 20 MALLOC_FREE, 21 MALLOC_HEAD, 22 MALLOC_CORE, 23 MALLOC_MODULE, 24 }; 25 26 enum arena_type { 27 ARENA_TYPE_USED = 0, 28 ARENA_TYPE_FREE = 1, 29 ARENA_TYPE_HEAD = 2, 30 ARENA_TYPE_DEAD = 3, 31 }; 32 enum heap { 33 HEAP_MAIN, 34 HEAP_LOWMEM, 35 NHEAP 36 }; 37 38 #define ARENA_MAGIC 0x20130117 39 40 struct free_arena_header; 41 42 /* 43 * This structure should be a power of two. This becomes the 44 * alignment unit. 45 */ 46 struct arena_header { 47 malloc_tag_t tag; 48 size_t attrs; /* Bits 0..1: Type 49 2..3: Heap, 50 4..31: MSB of the size */ 51 struct free_arena_header *next, *prev; 52 53 #ifdef DEBUG_MALLOC 54 unsigned long _pad[3]; 55 unsigned int magic; 56 #endif 57 }; 58 59 /* Pad to 2*sizeof(struct arena_header) */ 60 #define ARENA_PADDING ((2 * sizeof(struct arena_header)) - \ 61 (sizeof(struct arena_header) + \ 62 sizeof(struct free_arena_header *) + \ 63 sizeof(struct free_arena_header *))) 64 65 /* 66 * This structure should be no more than twice the size of the 67 * previous structure. 68 */ 69 struct free_arena_header { 70 struct arena_header a; 71 struct free_arena_header *next_free, *prev_free; 72 size_t _pad[ARENA_PADDING]; 73 }; 74 75 #define ARENA_SIZE_MASK (~(uintptr_t)(sizeof(struct arena_header)-1)) 76 #define ARENA_HEAP_MASK ((size_t)0xc) 77 #define ARENA_HEAP_POS 2 78 #define ARENA_TYPE_MASK ((size_t)0x3) 79 80 #define ARENA_ALIGN_UP(p) ((char *)(((uintptr_t)(p) + ~ARENA_SIZE_MASK) \ 81 & ARENA_SIZE_MASK)) 82 #define ARENA_ALIGN_DOWN(p) ((char *)((uintptr_t)(p) & ARENA_SIZE_MASK)) 83 84 #define ARENA_SIZE_GET(attrs) ((attrs) & ARENA_SIZE_MASK) 85 #define ARENA_HEAP_GET(attrs) (((attrs) & ARENA_HEAP_MASK) >> ARENA_HEAP_POS) 86 #define ARENA_TYPE_GET(attrs) ((attrs) & ARENA_TYPE_MASK) 87 88 #define ARENA_SIZE_SET(attrs, size) \ 89 ((attrs) = ((size) & ARENA_SIZE_MASK) | ((attrs) & ~ARENA_SIZE_MASK)) 90 #define ARENA_HEAP_SET(attrs, heap) \ 91 ((attrs) = (((heap) << ARENA_HEAP_POS) & ARENA_HEAP_MASK) | \ 92 ((attrs) & ~ARENA_HEAP_MASK)) 93 #define ARENA_TYPE_SET(attrs, type) \ 94 ((attrs) = ((attrs) & ~ARENA_TYPE_MASK) | \ 95 ((type) & ARENA_TYPE_MASK)) 96 97 extern struct free_arena_header __core_malloc_head[NHEAP]; 98 void __inject_free_block(struct free_arena_header *ah); 99
