Paged memory management. More...

#include <core.h>

Data Structures
union	page_t
	A pagetable page record. More...

struct	pagetable_t
	A pagetable structure. More...

Macros
#define	PAGE_SIZE 0x1000

#define	PAGE_SIZE_LARGE 0x200000

#define	PAGE_SIZE_HUGE 0x40000000

#define	PF_PRESENT (1 << 0)

#define	PF_RW (1 << 1)

#define	PF_USER (1 << 2)

#define	PF_PWT (1 << 3)

#define	PF_PCD (1 << 4)

#define	PF_ACCESS (1 << 5)

#define	PF_DIRTY (1 << 6)

#define	PF_PS (1 << 7)

#define	PF_GLOBAL (1 << 8)

#define	PF_SYSTEM (1 << 9)

#define	PGSHIFT_PML4E 39

#define	PGSHIFT_PDPTE 30

#define	PGSHIFT_PDE 21

#define	PGSHIFT_PTE 12

#define	PGMASK_ENTRY 0x1ff

#define	PGMASK_OFFSET 0x3ff

#define	PML4E(a) (((a) >> PGSHIFT_PML4E) & PGMASK_ENTRY)

#define	PDPTE(a) (((a) >> PGSHIFT_PDPTE) & PGMASK_ENTRY)

#define	PDE(a) (((a) >> PGSHIFT_PDE) & PGMASK_ENTRY)

#define	PTE(a) (((a) >> PGSHIFT_PTE) & PGMASK_ENTRY)

#define	PGPTR(pte) ((page_t *)((pte) & ~PGMASK_OFFSET))

Functions
void	page_init ()
	Initialize the page frame database. More...

void	pagetable_create (pagetable_t pt, void vaddr, uint64_t size)
	Create a new page table that can be used to associate virtual addresses with physical addresses. More...

void	pagetable_destroy (pagetable_t *pt)
	Destroy a page table. More...

void	pagetable_activate (pagetable_t *pt)
	Activate a page table on the CPU, so all virtual memory operations are performed relative to the page table. More...

void *	page_alloc (pagetable_t pt, void vaddr, int count)
	Allocate one or more pages contiguous in virtual memory. More...

void	page_free (pagetable_t pt, void vaddr, int count)
	Free one or more contiguous pages from virtual memory. More...

Detailed Description

Paged memory management.

Definition in file paging.h.

Data Structure Documentation

union page_t

A pagetable page record.

Contains 512 page table entries if the page holds a page table. Otherwise it contains 4096 bytes of memory.

Definition at line 54 of file paging.h.

Data Fields
uint64_t	entry[PAGE_SIZE/sizeof(uint64_t)]
uint8_t	memory[PAGE_SIZE]

struct pagetable_t

A pagetable structure.

Holds all the page table entries that map virtual addresses to physical addresses.

Definition at line 66 of file paging.h.

Data Fields
uint64_t	proot	Physical address of root page table (PML4T) entry.
uint64_t	vroot	Virtual address of root page table (PML4T) entry.
uint64_t	vnext	Virtual address to use for table's next page.
uint64_t	vterm	Boundary of pages used to store the table.

Macro Definition Documentation

#define PAGE_SIZE 0x1000

Definition at line 15 of file paging.h.

Referenced by acpi_init(), add_pte(), alloc_page(), cmd_test_heap(), grow_heap(), heap_create(), kmem_init(), map_range(), map_region(), next_fblock(), next_fblock_adj(), page_alloc(), page_free(), page_init(), pagetable_create(), pagetable_destroy(), and pgalloc().

#define PAGE_SIZE_LARGE 0x200000

Definition at line 16 of file paging.h.

Referenced by map_region(), and page_init().

#define PAGE_SIZE_HUGE 0x40000000

Definition at line 17 of file paging.h.

Referenced by map_region().

#define PF_PRESENT (1 << 0)

Definition at line 20 of file paging.h.

Referenced by add_pte(), alloc_page(), get_pdflags(), get_ptflags(), map_table(), and page_alloc().

#define PF_RW (1 << 1)

Definition at line 21 of file paging.h.

Referenced by add_pte(), alloc_page(), get_pdflags(), get_ptflags(), map_table(), and page_alloc().

#define PF_USER (1 << 2)

Definition at line 22 of file paging.h.

#define PF_PWT (1 << 3)

Definition at line 23 of file paging.h.

Referenced by get_pdflags(), and get_ptflags().

#define PF_PCD (1 << 4)

Definition at line 24 of file paging.h.

Referenced by get_pdflags(), and get_ptflags().

#define PF_ACCESS (1 << 5)

Definition at line 25 of file paging.h.

#define PF_DIRTY (1 << 6)

Definition at line 26 of file paging.h.

#define PF_PS (1 << 7)

Definition at line 27 of file paging.h.

Referenced by get_pdflags(), and is_mapped().

#define PF_GLOBAL (1 << 8)

Definition at line 28 of file paging.h.

Referenced by get_pdflags(), and get_ptflags().

#define PF_SYSTEM (1 << 9)

Definition at line 29 of file paging.h.

Referenced by add_pte(), alloc_page(), get_pdflags(), get_ptflags(), and pgfree_recurse().

#define PGSHIFT_PML4E 39

Definition at line 32 of file paging.h.

#define PGSHIFT_PDPTE 30

Definition at line 33 of file paging.h.

#define PGSHIFT_PDE 21

Definition at line 34 of file paging.h.

#define PGSHIFT_PTE 12

Definition at line 35 of file paging.h.

#define PGMASK_ENTRY 0x1ff

Definition at line 36 of file paging.h.

#define PGMASK_OFFSET 0x3ff

Definition at line 37 of file paging.h.

#define PML4E ( a ) (((a) >> PGSHIFT_PML4E) & PGMASK_ENTRY)

Definition at line 40 of file paging.h.

Referenced by add_pte(), create_huge_page(), create_large_page(), create_page(), create_small_page(), is_mapped(), and remove_pte().

#define PDPTE ( a ) (((a) >> PGSHIFT_PDPTE) & PGMASK_ENTRY)

Definition at line 41 of file paging.h.

Referenced by add_pte(), create_huge_page(), create_large_page(), create_page(), create_small_page(), is_mapped(), and remove_pte().

#define PDE ( a ) (((a) >> PGSHIFT_PDE) & PGMASK_ENTRY)

Definition at line 42 of file paging.h.

Referenced by add_pte(), create_large_page(), create_page(), create_small_page(), is_mapped(), and remove_pte().

#define PTE ( a ) (((a) >> PGSHIFT_PTE) & PGMASK_ENTRY)

Definition at line 43 of file paging.h.

Referenced by add_pte(), create_page(), create_small_page(), is_mapped(), and remove_pte().

#define PGPTR ( pte ) ((page_t *)((pte) & ~PGMASK_OFFSET))

Definition at line 46 of file paging.h.

Referenced by add_pte(), create_huge_page(), create_large_page(), create_page(), create_small_page(), is_mapped(), pgfree_recurse(), and remove_pte().

Function Documentation

void page_init ( )

Initialize the page frame database.

The page frame database manages the physical memory used by all memory pages known to the kernel.

Definition at line 107 of file paging.c.

Referenced by kmain().

void pagetable_create	(	pagetable_t *	pt,
		void *	vaddr,
		uint64_t	size
	)

Create a new page table that can be used to associate virtual addresses with physical addresses.

The page table includes protected mappings for kernel memory.

Parameters

[in]	pt	A pointer to the pagetable structure that will hold the page table.
[in]	vaddr	The virtual address within the new page table where the page table will be mapped.
[in]	size	Maximum size of the page table in bytes. Must be a multiple of PAGE_SIZE.

Returns: A handle to the created page table.

Definition at line 364 of file paging.c.

Referenced by cmd_test_heap().

void pagetable_destroy ( pagetable_t * pt )

Destroy a page table.

Parameters

[in] pt A handle to the page table to destroy.

Definition at line 383 of file paging.c.

Referenced by cmd_test_heap().

void pagetable_activate ( pagetable_t * pt )

Activate a page table on the CPU, so all virtual memory operations are performed relative to the page table.

Parameters

[in] pt A handle to the activated page table. Pass NULL to activate the kernel page table.

Definition at line 403 of file paging.c.

Referenced by cmd_test_heap().

void* page_alloc	(	pagetable_t *	pt,
		void *	vaddr,
		int	count
	)

Allocate one or more pages contiguous in virtual memory.

Parameters

[in]	pt	Handle to the page table from which to allocate the page(s).
[in]	vaddr	The virtual address of the first allocated page.
[in]	count	The number of contiguous virtual memory pages to allocate.

Returns: A virtual memory pointer to the first page allocated.

Definition at line 415 of file paging.c.

Referenced by grow_heap(), and heap_create().

void page_free	(	pagetable_t *	pt,
		void *	vaddr,
		int	count
	)

Free one or more contiguous pages from virtual memory.

Parameters

[in]	pt	Handle to ehte page table from which to free the page(s).
[in]	vaddr	The virtual address of the first allocated page.
[in]	count	The number of contiguous virtual memory pages to free.

Definition at line 425 of file paging.c.

Referenced by heap_destroy().

Data Structures

Macros

Functions

Detailed Description

Data Structure Documentation

Macro Definition Documentation

Function Documentation