Memory Management

Basic memory managment. More...

Macros
#define	MEM_BASIC_ALLOCATOR_MIN_PAGES   8192
	The minimum amount of pages that we will reserve for the basic allocator.
#define	MEM_BASIC_ALLOCATOR_RESERVE_PERCENTAGE   5
	The percentage of available memory that we will reserve for the basic allocator.

Functions
EFI_STATUS	mem_init (void)
	Initializes the basic memory allocator.
EFI_STATUS	mem_map_init (boot_memory_map_t *map)
	Initialize and load the memory map provided by the UEFI firmware.
void	mem_map_deinit (boot_memory_map_t *map)
	Deinitializes the memory map and frees any allocated resources.
void	mem_page_table_init (page_table_t *table, boot_memory_map_t *map, boot_gop_t *gop, boot_kernel_t *kernel)
	Initializes a page table for use by the kernel.

Detailed Description

Basic memory managment.

Handles the loading of the UEFI memory map and setting up a basic memory allocator for after we have exited boot services but before we jump to the kernel as we cant use the normal memory allocator after exiting boot services.

Macro Definition Documentation

MEM_BASIC_ALLOCATOR_MIN_PAGES

#define MEM_BASIC_ALLOCATOR_MIN_PAGES   8192

The minimum amount of pages that we will reserve for the basic allocator.

Definition at line 22 of file mem.h.

MEM_BASIC_ALLOCATOR_RESERVE_PERCENTAGE

#define MEM_BASIC_ALLOCATOR_RESERVE_PERCENTAGE   5

The percentage of available memory that we will reserve for the basic allocator.

This is rounded up to at least MEM_BASIC_ALLOCATOR_MIN_PAGES.

Definition at line 29 of file mem.h.

Function Documentation

mem_init()

EFI_STATUS mem_init

(

void

)

Initializes the basic memory allocator.

Returns

On success, EFI_SUCCESS. On failure, an error code.

Definition at line 22 of file mem.c.

References basicAllocator, BOOT_MEMORY_MAP_GET_DESCRIPTOR, boot_memory_map_t::length, map, MAX, MEM_BASIC_ALLOCATOR_MIN_PAGES, MEM_BASIC_ALLOCATOR_RESERVE_PERCENTAGE, mem_map_init(), and NULL.

Referenced by efi_main().

mem_map_deinit()

void mem_map_deinit

(

boot_memory_map_t *

map

)

Deinitializes the memory map and frees any allocated resources.

Parameters

map	The boot memory map structure to deinitialize.

Definition at line 83 of file mem.c.

References boot_memory_map_t::descriptors, boot_memory_map_t::length, map, and NULL.

Referenced by exit_boot_services().

mem_map_init()

EFI_STATUS mem_map_init

(

boot_memory_map_t *

map

)

Initialize and load the memory map provided by the UEFI firmware.

Parameters

map	The boot memory map structure to initialize.

Returns

On success, EFI_SUCCESS. On failure, an error code.

Definition at line 64 of file mem.c.

References BOOT_MEMORY_MAP_GET_DESCRIPTOR, boot_memory_map_t::descriptors, boot_memory_map_t::descSize, boot_memory_map_t::descVersion, boot_memory_map_t::key, boot_memory_map_t::length, map, NULL, and PML_LOWER_TO_HIGHER.

Referenced by exit_boot_services(), and mem_init().

mem_page_table_init()

void mem_page_table_init	(	page_table_t *	table,
		boot_memory_map_t *	map,
		boot_gop_t *	gop,
		boot_kernel_t *	kernel
	)

Initializes a page table for use by the kernel.

This function sets up a new page table and maps the memory regions specified in the boot memory map, the graphics output protocol (GOP) framebuffer, and the kernel itself.

It is intended to be used after exiting UEFI boot services and will fill the screen with a solid color and halt the CPU if it encounters an error, as there is very little we can do in that situation.

Parameters

table	The page table to initialize.
map	The boot memory map containing memory descriptors to be mapped.
gop	The graphics output protocol information for mapping the framebuffer.
kernel	The kernel information for mapping the kernel binary.

Definition at line 125 of file mem.c.

References basic_allocator_alloc_pages(), basicAllocator, BOOT_MEMORY_MAP_GET_DESCRIPTOR, BYTES_TO_PAGES, ERR, gop, boot_memory_map_t::length, map, MAX, NULL, PAGE_SIZE, page_table_init(), page_table_map(), panic_without_boot_services(), boot_gop_t::physAddr, boot_kernel_t::physStart, PML_CALLBACK_NONE, PML_HIGHER_HALF_START, PML_LOWER_HALF_END, PML_PRESENT, PML_WRITE, boot_gop_t::size, boot_kernel_t::size, boot_gop_t::virtAddr, and boot_kernel_t::virtStart.

Referenced by exit_boot_services().