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IOOutputQueue.h

Overview

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Classes

IOOutputQueue

A packet queue that supports multiple producers and a single consumer.

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Enumerations

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OutputCommands

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A command requested by the target.

enum { 
    kIOOutputCommandMask = 0xff00, 
    kIOOutputCommandNone = 0x0000, 
    kIOOutputCommandStall = 0x0100 
};  

Constants

kIOOutputCommandMask

Define the command field in the return code.

kIOOutputCommandNone

No command.

kIOOutputCommandStall

A command to stall the queue.

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OutputHandlerReturnCodes

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Common return codes returned by the target's output handler.

enum { 
    kIOReturnOutputSuccess = (
        kIOOutputStatusAccepted | kIOOutputCommandNone), 
    kIOReturnOutputDropped = (
        kIOOutputStatusDropped | kIOOutputCommandNone), 
    kIOReturnOutputStall = (
        kIOOutputStatusRetry | kIOOutputCommandStall) 
};  

Constants

kIOReturnOutputSuccess

Packet was accepted.

kIOReturnOutputDropped

Packet was dropped.

kIOReturnOutputStall

Stall the queue and retry the same packet when the queue is restarted.

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OutputPacketStatus

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The status of the packet sent to the target.

enum { 
    kIOOutputStatusMask = 0x00ff, 
    kIOOutputStatusAccepted = 0x0000, 
    kIOOutputStatusDropped = 0x0001, 
    kIOOutputStatusRetry = 0x0002 
};  

Constants

kIOOutputStatusMask

Define the status field in the return code.

kIOOutputStatusAccept

Packet was accepted by the target.

kIOOutputStatusDropped

Packet accepted, but was also dropped.

kIOOutputStatusRetry

Target ran out of resources, and is unable to accept the packet. The ownership of the packet reverts back to the queue.

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Last Updated: 2008-12-19