coreboot/src/lib/malloc.c

77 lines
1.8 KiB
C

#include <stdlib.h>
#include <console/console.h>
#if CONFIG(DEBUG_MALLOC)
#define MALLOCDBG(x...) printk(BIOS_SPEW, x)
#else
#define MALLOCDBG(x...)
#endif
extern unsigned char _heap, _eheap;
static void *free_mem_ptr = &_heap; /* Start of heap */
static void *free_mem_end_ptr = &_eheap; /* End of heap */
static void *free_last_alloc_ptr = &_heap; /* End of heap before
last allocation */
/* We don't restrict the boundary. This is firmware,
* you are supposed to know what you are doing.
*/
void *memalign(size_t boundary, size_t size)
{
void *p;
MALLOCDBG("%s Enter, boundary %zu, size %zu, free_mem_ptr %p\n",
__func__, boundary, size, free_mem_ptr);
free_mem_ptr = (void *)ALIGN((unsigned long)free_mem_ptr, boundary);
p = free_mem_ptr;
free_mem_ptr += size;
/*
* Store last allocation pointer after ALIGN, as malloc() will
* return it. This may cause n bytes of gap between allocations
* where n < boundary.
*/
free_last_alloc_ptr = p;
if (free_mem_ptr >= free_mem_end_ptr) {
printk(BIOS_ERR, "memalign(boundary=%zu, size=%zu): failed: ",
boundary, size);
printk(BIOS_ERR, "Tried to round up free_mem_ptr %p to %p\n",
p, free_mem_ptr);
printk(BIOS_ERR, "but free_mem_end_ptr is %p\n",
free_mem_end_ptr);
die("Error! memalign: Out of memory (free_mem_ptr >= free_mem_end_ptr)");
}
MALLOCDBG("memalign %p\n", p);
return p;
}
void *malloc(size_t size)
{
return memalign(sizeof(u64), size);
}
void free(void *ptr)
{
if (ptr == NULL)
return;
if (ptr < (void *)&_heap || ptr >= free_mem_end_ptr) {
printk(BIOS_WARNING, "Warning - Pointer passed to %s is not "
"pointing to the heap\n", __func__);
return;
}
/*
* Rewind the heap pointer to the end of heap
* before the last successful malloc().
*/
if (ptr == free_last_alloc_ptr) {
free_mem_ptr = free_last_alloc_ptr;
free_last_alloc_ptr = NULL;
}
}