Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Merge r268024, 268025:

Fix a case in ndling ATA_PASSTHROUGH commands that have an unaligned buffer.
This impacts some home-rolled SMART tools.

In rare cases, a SATA drive can stop responding to commands and trigger a
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.

Obtained from: Netflix, Inc.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Improve logging around some of the isci(4) reset and recovery paths.

Sponsored by: Intel
Discussed with: scottl
Approved by: re (marius)
MFC after: 1 week

Fix r231134. svn:keywords needs to be 'FreeBSD=%H', not 'FreeBSD:%H'.

Approved by: scottl

Add svn:keywords for isci driver files.

Sponsored by: Intel
Approved by: scottl

Add isci(4) driver for amd64 and i386 targets.

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

Add all isci driver source code to sys/dev/isci for the Intel C600
(Patsburg) integrated SAS controller.

sys/dev/isci contains all files specific to FreeBSD.
sys/dev/isci/scil contains OS-agnostic library maintained by Intel and
modified to best integrate into FreeBSD kernel build environment.

Sponsored by: Intel
Reviewed by: scottl