Sigma0 API

Sigma0 API bindings. More...

Collaboration diagram for Sigma0 API:

Modules
	Internal constants
	Internal sigma0 definitions.

Files
file	sigma0.h
	Sigma0 interface.

Enumerations
enum	l4sigma0_return_flags_t {   L4SIGMA0_OK , L4SIGMA0_NOTALIGNED , L4SIGMA0_IPCERROR , L4SIGMA0_NOFPAGE ,   L4SIGMA0_4 , L4SIGMA0_5 , L4SIGMA0_SMALLERFPAGE }
	Return flags of libsigma0 functions. More...

Functions
l4_kernel_info_t *	l4sigma0_map_kip (l4_cap_idx_t sigma0, void *addr, unsigned log2_size)
	Map the kernel info page from sigma0 to addr.
int	l4sigma0_map_mem (l4_cap_idx_t sigma0, l4_addr_t phys, l4_addr_t virt, l4_addr_t size)
	Request a memory mapping from sigma0.
int	l4sigma0_map_iomem (l4_cap_idx_t sigma0, l4_addr_t phys, l4_addr_t virt, l4_addr_t size, int cached)
	Request IO memory from sigma0.
int	l4sigma0_map_anypage (l4_cap_idx_t sigma0, l4_addr_t map_area, unsigned log2_map_size, l4_addr_t *base, unsigned sz)
	Request an arbitrary free page of RAM.
void	l4sigma0_debug_dump (l4_cap_idx_t sigma0)
	Request sigma0 to dump internal debug information.
char const *	l4sigma0_map_errstr (int err)
	Get user readable error messages for the return codes.

Detailed Description

Sigma0 API bindings.

Convenience bindings for the Sigma0 protocol.

Enumeration Type Documentation

l4sigma0_return_flags_t

enum l4sigma0_return_flags_t

Return flags of libsigma0 functions.

Enumerator
L4SIGMA0_OK	Ok.
L4SIGMA0_NOTALIGNED	Phys, virt or size not aligned.
L4SIGMA0_IPCERROR	IPC error.
L4SIGMA0_NOFPAGE	No fpage received.
L4SIGMA0_SMALLERFPAGE	Superpage requested but smaller flexpage received.

Definition at line 78 of file sigma0.h.

Function Documentation

l4sigma0_debug_dump()

void l4sigma0_debug_dump

(

l4_cap_idx_t

sigma0

)

Request sigma0 to dump internal debug information.

Parameters

sigma0

Capability selector for the sigma0 gate.

The debug information, such as internal memory maps, as well as statistics about the internal allocators is dumped to the kernel debugger.

l4sigma0_map_anypage()

int l4sigma0_map_anypage	(	l4_cap_idx_t	sigma0,
		l4_addr_t	map_area,
		unsigned	log2_map_size,
		l4_addr_t *	base,
		unsigned	sz
	)

Request an arbitrary free page of RAM.

Parameters

	sigma0	Capability selector for the sigma0 gate.
	map_area	The base address of the local virtual memory area where the page should be mapped.
	log2_map_size	The size of the requested page log 2 (the size in bytes is 2^log2_map_size). This must be at least the minimal page size. By specifing larger sizes the largest possible hardware page size will be used.
[out]	base	Physical address of the page received (i.e. the send base of the received mapping if any).
	sz	Size to map by the server in 2^sz bytes.

Return values

0	Success.
-L4SIGMA0_IPCERROR	IPC error.
-L4SIGMA0_NOFPAGE	No fpage received.

This function requests arbitrary free memory from sigma0. It should be used whenever spare memory is needed, instead of requesting specific physical memory with l4sigma0_map_mem().

See l4sigma0_map_errstr() to get a description of the return value.

l4sigma0_map_errstr()

char const * l4sigma0_map_errstr ( int  err )

inline

Get user readable error messages for the return codes.

Parameters

err	The error code reported by the map functions.

Returns

A string containing the error message.

Definition at line 210 of file sigma0.h.

l4sigma0_map_iomem()

int l4sigma0_map_iomem	(	l4_cap_idx_t	sigma0,
		l4_addr_t	phys,
		l4_addr_t	virt,
		l4_addr_t	size,
		int	cached
	)

Request IO memory from sigma0.

Parameters

sigma0	Capability selector for the sigma0 gate.
phys	The physical address to be requested (page aligned).
virt	The virtual address where the memory should be mapped to (page aligned).
size	The size of the IO memory area to be mapped (multiple of page size)
cached	Requests cacheable IO memory if 1 and uncached if 0.

Return values

0	Success.
-L4SIGMA0_NOTALIGNED	phys, virt, or size are not aligned.
-L4SIGMA0_IPCERROR	IPC error.
-L4SIGMA0_NOFPAGE	No fpage received.

This function is similar to l4sigma0_map_mem(), the difference is that it requests IO memory. IO memory is everything that is not known to be normal RAM. Also ACPI tables or the BIOS memory is treated as IO memory.

See l4sigma0_map_errstr() to get a description of the return value.

l4sigma0_map_kip()

l4_kernel_info_t * l4sigma0_map_kip	(	l4_cap_idx_t	sigma0,
		void *	addr,
		unsigned	log2_size
	)

Map the kernel info page from sigma0 to addr.

Parameters

sigma0	Capability selector for the sigma0 gate.
addr	Start of the receive window to receive KIP in.
log2_size	Size of the receive window to receive KIP in.

Returns

Address KIP was mapped to, 0 indicates an error.

l4sigma0_map_mem()

int l4sigma0_map_mem	(	l4_cap_idx_t	sigma0,
		l4_addr_t	phys,
		l4_addr_t	virt,
		l4_addr_t	size
	)

Request a memory mapping from sigma0.

Parameters

sigma0	Capability selector for the sigma0 gate.
phys	The physical address of the requested page (must be at least aligned to the minimum page size).
virt	The virtual address where the paged should be mapped in the local address space (must be at least aligned to the minimum page size).
size	The size of the requested page, this must be a multiple of the minimum page size.

Return values

0	Success.
-L4SIGMA0_NOTALIGNED	phys, virt, or size are not aligned.
-L4SIGMA0_IPCERROR	IPC error.
-L4SIGMA0_NOFPAGE	No fpage received.

This function only maps normal RAM. To map other memory, use l4sigma0_map_iomem(). See also there for the distinction between both memory types.

This is the direct method to request memory from sigma0. There is also the indirect method where sigma0 will answer page faults with a mapping that is one-to-one between the faulting virtual page and the backing physical page. See L4::Pager::page_fault(). For an overview of the memory hierarchy, see Memory management - Data Spaces and the Region Map.

See l4sigma0_map_errstr() to get a description of the return value.