Intel EP80579 User Manual

Intel

®

 EP80579 Software for Security Applications on Intel

®

 QuickAssist Technology

PG

August 2009

18

Order Number: 320183-004US

This section describes the context in which the EP80579 security software code is 

executed, which is important in terms of understanding concurrency, or where locking 

may be required, for example.

Code which implements the Acceleration APIs is library code, and is executed in the 

context of whatever thread or interrupt context from which it is called.  All of the 

EP80579 security software APIs document the context in which they can be called, 

specifically whether they may sleep and therefore are suitable for calling in a context 

which may not sleep, such as ISRs or certain types of "bottom halves" including softirq 

and tasklet. They also document whether they are thread-safe. 

 lists the API documentation supported in this 

release. 

The remainder of EP80579 security software code runs in a well-defined context, 

whether it is process context or some form of interrupt context as described below.

• Interrupt handlers are registered for all interrupts from devices managed by 

EP80579 security software, specifically the GbE MACs, and the ring controller on 

the ASU. This code runs in the ISR (interrupt top half) context.

• Many of the Acceleration APIs support one or both of asynchronous and 

synchronous modes.

— In asynchronous mode: when the request has been carried out on the SSU, a 

“function completion callback” is typically invoked in a non-sleeping bottom half 

context (specifically, a tasklet, on Linux). For more on this topic, see 

— In synchronous mode: when the request has been sent to the SSU, the calling 

thread is blocked, pending on a wait queue. When the response is received 

from the SSU, the calling thread is de-queued, and thereby unbocked.

 describes the mapping between the software components described in 

, and the kernel modules that are created by the 

build system.

OCF Shim

Acceleration/shims/OCF_Shim

Acceleration System Driver

Acceleration/drivers/icp_asd

Lookaside Crypto Access Layer

Acceleration/library/icp_crypto/look_aside_crypto

QAT Access Layer

Acceleration/library/icp_crypto/QATAL 

Debug Infrastructure

Acceleration/library/icp_debug/DCC

Management Interface Module

Acceleration/library/icp_debug/MIL

Hardware Abstraction Layer 

(part of Hardware Services Layer)

Acceleration/library/icp_services/RuntimeTargetLibrary

Operating System Abstraction Layer

Acceleration/library/icp_utils/OSAL

Firmware Driver for SSU

Acceleration/firmware