/* SPDX-License-Identifier: GPL-2.0-only */ #include <console/console.h> #include <stdlib.h> #include <string.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_UP((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, "%s(boundary=%zu, size=%zu): failed: ", __func__, 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); printk(BIOS_ERR, "Error! %s: Out of memory " "(free_mem_ptr >= free_mem_end_ptr)", __func__); return NULL; } MALLOCDBG("%s %p\n", __func__, p); return p; } void *malloc(size_t size) { return memalign(sizeof(u64), size); } void *calloc(size_t nitems, size_t size) { void *p = malloc(nitems * size); if (p) memset(p, 0, nitems * size); return p; } void free(void *ptr) { if (ptr == NULL) return; if (ptr < (void *)&_heap || ptr >= free_mem_end_ptr) { printk(BIOS_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; } }