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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
OS Components & Operations
SMMUMAN User's Guide
SMMUMAN Client API Reference
This chapter describes the API that SMMUMAN clients can use to access and manage the smmuman services.
smmu_init()
Initialize contact between the client process and smmuman

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
- Quickstart Guide
- System Architecture
  The System Architecture guide accompanies the QNX OS and is intended for both application developers and end-users.
- OS Components & Operations
  - Boot Optimization Guide
    The Boot Optimization Guide describes techniques you can use to reduce the time from your board's initial power on until you have a fully functional QNX system running on the board.
  - Building Embedded Systems
    The Building Embedded Systems guide is intended for developers who are developing or building BSPs for QNX OS embedded systems.
  - Customizing a BSP
    While QNX provides Board Support Packages (BSPs) for many common platforms and their individual variants, in some cases, you need a BSP for a board that QNX does not provide. If this is the case, you can modify a QNX BSP or develop your own.
  - Device Publishers Developer's Guide
  - High Availability Framework Developer's Guide
  - High-Performance Networking Stack (io-sock) User's Guide
    This guide contains instructions for implementing and using the QNX OS High-Performance Networking Stack and its manager, io-sock.
  - PCI Server User's Guide
  - Performance Tuning User's Guide
  - QNX Filesystem for Safety User's Guide
  - SMMUMAN User's Guide
    - SMMUMAN Architecture
      This chapter presents the architecture of the SMMUMAN, and its responsibilities and behavior.
    - smmuman
      System memory management unit (IOMMU/SMMU) manager
    - SMMUMAN Client API Reference
      This chapter describes the API that SMMUMAN clients can use to access and manage the smmuman services.
      - smmu_* data structures
        Data structures used by the SMMUMAN client API
      - Enumerated values and constants
        Enumerated values used by the SMMUMAN client API
      - smmu_device_add_generic()
        Add a device to a SMMU object, or remove it
      - smmu_device_add_mmio()
        Add an MMIO device to a SMMU object, or remove it
      - smmu_device_add_pci()
        Add a PCI device to a SMMU object, or remove it
      - smmu_device_report_reserved()
        Report which memory region or regions are reserved for a DMA device that requires device-specific reserved memory
      - smmu_fini()
        Terminate the client’s connection with smmuman
      - smmu_init()
        Initialize contact between the client process and smmuman
      - smmu_mapping_add()
        Add a memory mapping to or remove a memory mapping from a SMMU object
      - smmu_obj_create()
        Create a SMMU object to which devices and their memory mappings can be added
      - smmu_obj_destroy()
        Destroy a SMMU object
      - smmu_safety()
        Query the smmuman service for its safety status
      - smmu_xfer_notify()
        Register to be notified of DMA device memory access transgressions
      - smmu_xfer_status()
        Retrieve the record of a DMA device’s attempt to access memory outside its permitted region or regions
    - Example program
      The following is an example program that connects to the smmuman service and monitors IOMMU/SMMU transgressions reported by the service.
    - Terminology
      The following terms are used throughout the SMMUMAN documentation.
  - System Analysis Toolkit (SAT) User's Guide
  - Technotes
  - User's Guide
    The QNX OS User's Guide is intended for all users of a QNX OS system, from system administrators to end users.
- Graphics
- Programming
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX OS system and developers who want to create a QNX OS resource manager free from vulnerabilities.
- Utilities & Libraries
- Migrating to QNX OS 8.0
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX OS in the Amazon cloud environment.
QNX Toolkit for Visual Studio Code
This User's Guide describes the QNX^® Toolkit for Visual Studio Code. The guide introduces you to the QNX Toolkit by explaining the QNX development environment and how to build, run, and debug your QNX^® Operating System (OS) applications and systems.
QNX Hypervisor User's Guide
This User's Guide explains the QNX hypervisor architecture and provides instructions for installing and running a QNX Hypervisor system, changing system components and configuration, and using hypervisor features such as virtual devices (vdevs).
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation, explains how to obtain technical support, and provides some information about licensing.

smmu_init()

QNX SDP8.0SMMUMAN User's GuideAPIConfigurationUtilities

Initialize contact between the client process and smmuman

Synopsis:

#include <smmu.h>

int smmu_init(unsigned flags);

Arguments:

flags: Must be 0 (zero).

Library:

libsmmu.a

Description:

The smmu_init() function checks that the smmuman service is running, and connects the client to the service.

To use smmu_init() your smmuman client must have the SMMU_ABILITY_ATTACH_NAME ("smmu/attach") custom ability before calling the function.

If the client will use the SMF_TARGET flag when calling smmu_mapping_add() it must also have the SMMU_ABILITY_TARGET_NAME ("smmu/target") custom ability before calling smmu_init().

Use procmgr_ability_lookup() to obtain these custom abilities, and keep the returned ability identifiers in your list of allowed abilities. See procmgr_ability_lookup() and procmgr_ability() in the C Library Reference.

Returns:

-1: Failure: errno is set.
≥0: Success: a connection with the service has been established.

Page updated: August 11, 2025