reset device task request from the driver. If the drive fails to respond
with a signature FIS, the driver would previously get into an endless retry
loop, stalling all I/O to the drive and keeping user processes stranded.
Instead, fail the i/o and invalidate the device if the task management
command times out. This is controllable with the sysctl and tunable
hw.isci.fail_on_task_timeout
dev.isci.0.fail_on_task_timeout
The default for these is 1.
Reviewed by: jimharris
Obtained from: Netflix, Inc.
MFC after: 2 days
The isci driver is for the integrated SAS controller in the Intel C600
(Patsburg) chipset. Source files in sys/dev/isci directory are
FreeBSD-specific, and sys/dev/isci/scil subdirectory contains
an OS-agnostic library (SCIL) published by Intel to control the SAS
controller. This library is used primarily as-is in this driver, with
some post-processing to better integrate into the kernel build
environment.
isci.4 and a README in the sys/dev/isci directory contain a few
additional details.
This driver is only built for amd64 and i386 targets.
Sponsored by: Intel
Reviewed by: scottl
Approved by: scottl