#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include "malloc.h"
#include "core.h"
#include <syslinux/memscan.h>

struct free_arena_header __core_malloc_head[NHEAP];

//static __hugebss char main_heap[128 << 10];
extern char __lowmem_heap[];
extern char free_high_memory[];

#define E820_MEM_MAX 0xfff00000	/* 4 GB - 1 MB */
int scan_highmem_area(void *data, addr_t start, addr_t len, bool is_ram)
{
	struct free_arena_header *fp;

	(void)data;

	dprintf("start = %x, len = %x, is_ram = %d", start, len, is_ram);

	if (start < 0x100000 || start > E820_MEM_MAX
			     || !is_ram)
		return 0;

	if (start < __com32.cs_memsize) {
		len -= __com32.cs_memsize - start;
		start = __com32.cs_memsize;
	}
	if (len > E820_MEM_MAX - start)
		len = E820_MEM_MAX - start;

	if (len >= 2 * sizeof(struct arena_header)) {
		fp = (struct free_arena_header *)start;
		fp->a.attrs = ARENA_TYPE_USED | (HEAP_MAIN << ARENA_HEAP_POS);
		ARENA_SIZE_SET(fp->a.attrs, len);
		dprintf("will inject a block start:0x%x size 0x%x", start, len);
		__inject_free_block(fp);
	}

	__com32.cs_memsize = start + len; /* update the HighMemSize */
	return 0;
}

#if 0
static void mpool_dump(enum heap heap)
{
	struct free_arena_header *head = &__core_malloc_head[heap];
	struct free_arena_header *fp;
	int size, type, i = 0;
	addr_t start, end;

	fp = head->next_free;
	while (fp != head) {
		size = ARENA_SIZE_GET(fp->a.attrs);
		type = ARENA_TYPE_GET(fp->a.attrs);
		start = (addr_t)fp;
		end = start + size;
		printf("area[%d]: start = 0x%08x, end = 0x%08x, type = %d\n",
			i++, start, end, type);
		fp = fp->next_free;
	}
}
#endif

void mem_init(void)
{
	struct free_arena_header *fp;
	int i;
	uint16_t *bios_free_mem = (uint16_t *)0x413;

	//dprintf("enter");

	/* Initialize the head nodes */
	fp = &__core_malloc_head[0];
	for (i = 0 ; i < NHEAP ; i++) {
	fp->a.next = fp->a.prev = fp->next_free = fp->prev_free = fp;
	fp->a.attrs = ARENA_TYPE_HEAD | (i << ARENA_HEAP_POS);
	fp->a.tag = MALLOC_HEAD;
	fp++;
	}
	
	//dprintf("__lowmem_heap = 0x%p bios_free = 0x%p",
	//	__lowmem_heap, *bios_free_mem);
	
	/* Initialize the lowmem heap */
	fp = (struct free_arena_header *)__lowmem_heap;
	fp->a.attrs = ARENA_TYPE_USED | (HEAP_LOWMEM << ARENA_HEAP_POS);
	ARENA_SIZE_SET(fp->a.attrs, (*bios_free_mem << 10) - (uintptr_t)fp);
	__inject_free_block(fp);

	/* Initialize the main heap */
	__com32.cs_memsize = (size_t)free_high_memory;
	syslinux_scan_memory(scan_highmem_area, NULL);
}
