UEFI Support¶

UEFI stub library functions¶

efi_status_t efi_get_memory_map(struct efi_boot_memmap *map)¶: get memory map

Parameters

struct efi_boot_memmap *map: on return pointer to memory map

Description

Retrieve the UEFI memory map. The allocated memory leaves room for up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries.

Return

status code

efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr, unsigned long max)¶: Allocate memory pages

Parameters

unsigned long size: minimum number of bytes to allocate
unsigned long *addr: On return the address of the first allocated page. The first allocated page has alignment EFI_ALLOC_ALIGN which is an architecture dependent multiple of the page size.
unsigned long max: the address that the last allocated memory page shall not exceed

Description

Allocate pages as EFI_LOADER_DATA. The allocated pages are aligned according to EFI_ALLOC_ALIGN. The last allocated page will not exceed the address given by max.

Return

status code

void efi_free(unsigned long size, unsigned long addr)¶: free memory pages

Parameters

unsigned long size: size of the memory area to free in bytes
unsigned long addr: start of the memory area to free (must be EFI_PAGE_SIZE aligned)

Description

size is rounded up to a multiple of EFI_ALLOC_ALIGN which is an architecture specific multiple of EFI_PAGE_SIZE. So this function should only be used to return pages allocated with efi_allocate_pages() or efi_low_alloc_above().