Memory management functions and structures. More...

Collaboration diagram for Memory Management:

Topics
	Paging
	A platform-independent interface to map/unmap virtual memory to physical memory.

	Physical Memory Manager
	Allocate/free the physical memory, in the form of physical frames.

Classes
struct	pagefault_t

struct	vmap_t

Macros
#define	pfn_va(pfn) ((ptr_t) (platform_info->direct_map_base + (pfn) * (MOS_PAGE_SIZE)))

#define	va_pfn(va) ((((ptr_t) (va)) - platform_info->direct_map_base) / MOS_PAGE_SIZE)

#define	va_phyframe(va) (&phyframes[va_pfn(va)])

#define	phyframe_va(frame) ((ptr_t) pfn_va(phyframe_pfn(frame)))

#define	pa_va(pa) ((ptr_t) (pa) + platform_info->direct_map_base)

#define	mm_free_page(frame) pmm_free_frames(frame, 1)

#define	mm_free_pages(frame, npages) pmm_free_frames(frame, npages)

Typedefs
typedef struct _vmap	vmap_t

typedef vmfault_result_t(*	vmfault_handler_t) (vmap_t vmap, ptr_t fault_addr, pagefault_t info)

Enumerations
enum	vmap_content_t { VMAP_UNKNOWN = 0 , VMAP_HEAP , VMAP_STACK , VMAP_FILE , VMAP_MMAP , VMAP_DMA }

enum	vmap_type_t { VMAP_TYPE_PRIVATE = MMAP_PRIVATE , VMAP_TYPE_SHARED = MMAP_SHARED }

enum	vmfault_result_t { VMFAULT_COMPLETE , VMFAULT_MAP_BACKING_PAGE_RO , VMFAULT_MAP_BACKING_PAGE , VMFAULT_COPY_BACKING_PAGE , VMFAULT_CANNOT_HANDLE = 0xff }

Functions
phyframe_t *	mm_get_free_page (void)

phyframe_t *	mm_get_free_page_raw (void)

phyframe_t *	mm_get_free_pages (size_t npages)

mm_context_t *	mm_create_context (void)
	Create a user-mode platform-dependent page table.

void	mm_destroy_context (mm_context_t *table)
	Destroy a user-mode platform-dependent page table.

void	mm_lock_ctx_pair (mm_context_t ctx1, mm_context_t ctx2)
	Lock and unlock a pair of mm_context_t objects.

void	mm_unlock_ctx_pair (mm_context_t ctx1, mm_context_t ctx2)

__nodiscard mm_context_t *	mm_switch_context (mm_context_t *new_ctx)

vmap_t *	vmap_create (mm_context_t *mmctx, ptr_t vaddr, size_t npages)
	Create a vmap object and insert it into the address space.

void	vmap_destroy (vmap_t *vmap)
	Destroy a vmap object, and unmmap the region.

vmap_t *	vmap_obtain (mm_context_t mmctx, ptr_t vaddr, size_t out_offset)
	Get the vmap object for a virtual address.

vmap_t *	vmap_split (vmap_t *vmap, size_t split)
	Split a vmap object into two, at the specified offset.

vmap_t *	vmap_split_for_range (vmap_t *vmap, size_t rstart_pgoff, size_t rend_pgoff)
	Split a vmap to get a vmap object for a range of pages.

void	vmap_finalise_init (vmap_t *vmap, vmap_content_t content, vmap_type_t type)
	Finalize the initialization of a vmap object.

vmfault_result_t	mm_resolve_cow_fault (vmap_t vmap, ptr_t fault_addr, pagefault_t info)
	Helper function to resolve a copy-on-write fault.

void	mm_handle_fault (ptr_t fault_addr, pagefault_t *info)
	Handle a page fault.

Detailed Description

Memory management functions and structures.

Macro Definition Documentation

◆ pfn_va

#define pfn_va ( pfn ) ((ptr_t) (platform_info->direct_map_base + (pfn) * (MOS_PAGE_SIZE)))

Definition at line 76 of file mm.h.

Referenced by dmabuf_share(), dmabuf_unshare(), initrd_read(), platform_pml2e_get_pml1(), platform_pml3e_get_pml2(), platform_pml4e_get_pml3(), x86_initialise_phyframes_array(), and x86_paging_setup().

◆ va_pfn

#define va_pfn ( va ) ((((ptr_t) (va)) - platform_info->direct_map_base) / MOS_PAGE_SIZE)

Definition at line 77 of file mm.h.

Referenced by limine_entry(), pml2_traverse(), and pml2e_get_or_create_pml1().

◆ va_phyframe

#define va_phyframe ( va ) (&phyframes[va_pfn(va)])

Definition at line 78 of file mm.h.

Referenced by __destroy_page_table(), pipe_close_one_end(), slab_impl_free_page(), and thread_destroy().

◆ phyframe_va

#define phyframe_va ( frame ) ((ptr_t) pfn_va(phyframe_pfn(frame)))

Definition at line 79 of file mm.h.

Referenced by __create_page_table(), cpio_fill_cache(), mm_copy_page(), mm_get_free_page(), pipe_create(), process_do_fork(), register_sysfs_acpi_node(), slab_impl_new_page(), sysfs_expand_buffer(), sysfs_fops_read(), sysfs_printf(), sysfs_put_data(), thread_new(), userfs_inode_cache_fill_cache(), vfs_read_pagecache(), vfs_write_pagecache(), and zero_page().

◆ pa_va

#define pa_va ( pa ) ((ptr_t) (pa) + platform_info->direct_map_base)

Definition at line 80 of file mm.h.

Referenced by do_handle_sdt_header(), do_iterate_sdts(), ioapic_init(), lapic_memory_setup(), and platform_startup_late().

◆ mm_free_page

#define mm_free_page ( frame ) pmm_free_frames(frame, 1)

Definition at line 86 of file mm.h.

Referenced by __destroy_page_table().

◆ mm_free_pages

#define mm_free_pages	(		frame,
			npages ) pmm_free_frames(frame, npages)

Definition at line 87 of file mm.h.

Referenced by pipe_close_one_end(), slab_impl_free_page(), sysfs_expand_buffer(), sysfs_fops_release(), and thread_destroy().

Typedef Documentation

◆ vmap_t

typedef struct _vmap vmap_t

Definition at line 53 of file mm.h.

◆ vmfault_handler_t

typedef vmfault_result_t(* vmfault_handler_t) (vmap_t *vmap, ptr_t fault_addr, pagefault_t *info)

Definition at line 55 of file mm.h.

Enumeration Type Documentation

◆ vmap_content_t

enum vmap_content_t

Enumerator
VMAP_UNKNOWN
VMAP_HEAP
VMAP_STACK
VMAP_FILE
VMAP_MMAP
VMAP_DMA

Definition at line 19 of file mm.h.

◆ vmap_type_t

enum vmap_type_t

Enumerator
VMAP_TYPE_PRIVATE
VMAP_TYPE_SHARED

Definition at line 29 of file mm.h.

◆ vmfault_result_t

enum vmfault_result_t

Enumerator
VMFAULT_COMPLETE	no further action is needed, the page is correctly mapped now
VMFAULT_MAP_BACKING_PAGE_RO	the caller should map the backing page into the faulting address, and mark it non-writable
VMFAULT_MAP_BACKING_PAGE	the caller should map the backing page into the faulting address
VMFAULT_COPY_BACKING_PAGE	the caller should copy the backing page into the faulting address
VMFAULT_CANNOT_HANDLE	the handler cannot handle this fault