diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c index 4f8cb545ad..5bd4f4d7fc 100644 --- a/lib/efi_loader/efi_memory.c +++ b/lib/efi_loader/efi_memory.c @@ -65,9 +65,54 @@ static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b) return -1; } +static uint64_t desc_get_end(struct efi_mem_desc *desc) +{ + return desc->physical_start + (desc->num_pages << EFI_PAGE_SHIFT); +} + static void efi_mem_sort(void) { + struct list_head *lhandle; + struct efi_mem_list *prevmem = NULL; + bool merge_again = true; + list_sort(NULL, &efi_mem, efi_mem_cmp); + + /* Now merge entries that can be merged */ + while (merge_again) { + merge_again = false; + list_for_each(lhandle, &efi_mem) { + struct efi_mem_list *lmem; + struct efi_mem_desc *prev = &prevmem->desc; + struct efi_mem_desc *cur; + uint64_t pages; + + lmem = list_entry(lhandle, struct efi_mem_list, link); + if (!prevmem) { + prevmem = lmem; + continue; + } + + cur = &lmem->desc; + + if ((desc_get_end(cur) == prev->physical_start) && + (prev->type == cur->type) && + (prev->attribute == cur->attribute)) { + /* There is an existing map before, reuse it */ + pages = cur->num_pages; + prev->num_pages += pages; + prev->physical_start -= pages << EFI_PAGE_SHIFT; + prev->virtual_start -= pages << EFI_PAGE_SHIFT; + list_del(&lmem->link); + free(lmem); + + merge_again = true; + break; + } + + prevmem = lmem; + } + } } /** efi_mem_carve_out - unmap memory region