user_io_broker.h File Reference

Narrow kernel-invoked user GPIO message contract. More...

#include "nexus/core/status.h"

Go to the source code of this file.

Data Structures
struct	nx_user_io_message_t
	Untrusted copied message; identity never comes from users. More...
struct	nx_user_io_reply_t
	Fully initialized copied result; value is zero for errors/WRITE. More...
struct	nx_user_io_result_t
	Distinguish admission, cleanup retention and possible effect. More...

Typedefs
typedef struct nx_user_io_broker	nx_user_io_broker_t
	Broker and persistent kernel call storage stay provider private.
typedef struct nx_user_io_call	nx_user_io_call_t

Enumerations
enum	nx_user_io_constants { NX_USER_IO_ABI = 1U , NX_USER_GPIO_READ = 1U , NX_USER_GPIO_WRITE = 2U }
	Only scalar GPIO operations are admitted by this message ABI. More...

Functions
nx_user_io_result_t	nx_user_io_broker_gpio (nx_user_io_broker_t *broker, nx_user_io_call_t *call, const nx_user_io_message_t *message, nx_user_io_reply_t *reply)
	Execute one scalar GPIO message through a trusted gateway.
nx_user_io_result_t	nx_user_io_broker_gpio_finish (nx_user_io_broker_t *broker, nx_user_io_call_t *call)
	Retry retained cleanup without reading users or replaying IO.

Detailed Description

Narrow kernel-invoked user GPIO message contract.

Author

Nexus Team

Version

1.0.0

Date

2026-10-11

Copyright

Copyright (c) 2026 Nexus Team

Definition in file user_io_broker.h.

Typedef Documentation

nx_user_io_broker_t

typedef struct nx_user_io_broker nx_user_io_broker_t

Broker and persistent kernel call storage stay provider private.

Definition at line 44 of file user_io_broker.h.

nx_user_io_call_t

typedef struct nx_user_io_call nx_user_io_call_t

Definition at line 45 of file user_io_broker.h.

Enumeration Type Documentation

nx_user_io_constants

enum nx_user_io_constants

Only scalar GPIO operations are admitted by this message ABI.

Enumerator
NX_USER_IO_ABI
NX_USER_GPIO_READ
NX_USER_GPIO_WRITE

Definition at line 16 of file user_io_broker.h.

Function Documentation

nx_user_io_broker_gpio()

nx_user_io_result_t nx_user_io_broker_gpio	(	nx_user_io_broker_t *	broker,
		nx_user_io_call_t *	call,
		const nx_user_io_message_t *	message,
		nx_user_io_reply_t *	reply )

Execute one scalar GPIO message through a trusted gateway.

Returns

REJECTED has accepted=false, no pin/effect. ACCEPTED may already be detached or retain cleanup after a failure.

Note

Kernel-invoked privileged Thread with incoming masks clear, one serialized broker executor. Principal comes from the configured trusted kernel identity port. Pin both validated memory ranges before any GPIO call; snapshot input once, copy an initialized reply. Kernel call storage is zero-initialized outside user RAM and must outlive retained pins. No OS SVC/MPU/TZ wiring or user privilege elevation is provided by this component.

nx_user_io_broker_gpio_finish()

nx_user_io_result_t nx_user_io_broker_gpio_finish	(	nx_user_io_broker_t *	broker,
		nx_user_io_call_t *	call )

Retry retained cleanup without reading users or replaying IO.

Note

Same privileged serialized kernel owner, incoming masks clear. Successful unpin follows actual provider/observer drain; a failed unpin keeps memory, call slot and identity retained. Does not imply that a previously performed GPIO write can be reversed.