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

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

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

Extend some 32-bit fields and variables to 64-bit to prevent overflow
when calculating stats in nvmecontrol perftest.

Sponsored by: Intel
Reported by: Joe Golio <joseph.golio@emc.com>
Reviewed by: carl
Approved by: re (hrs)
MFC after: 1 week

Update copyright dates.

MFC after: 3 days

Change a number of malloc(9) calls to use M_WAITOK instead of
M_NOWAIT.

Sponsored by: Intel
Suggested by: carl
Reviewed by: carl

Create struct nvme_status.

NVMe error log entries include status, so breaking this out into
its own data structure allows it to be included in both the
nvme_completion data structure as well as error log entry data
structures.

While here, expose nvme_completion_is_error(), and change all of
the places that were explicitly looking at sc/sct bits to use this
macro instead.

Sponsored by: Intel
Reviewed by: carl

Revert r244549.

This change was originally intended to account for test kthreads under
the nvmecontrol process, but jhb indicated it may not be safe to
associate kthreads with userland processes and this could have
unintended consequences.

I did not observe any problems with this change, but my testing didn't
exhaust the kinds of corner cases that could cause problems. It is not
that important to account for these test threads under nvmecontrol, so I
am just reverting this change for now.

On a related note, the part of this patch for <= 7.x fails compilation
so reverting this fixes that too.

Suggested by: jhb

Put kthreads under curproc so they are attached to nvmecontrol rather
than pid 0.

Sponsored by: Intel

This is the first of several commits which will add NVM Express (NVMe)
support to FreeBSD. A full description of the overall functionality
being added is below. nvmexpress.org defines NVM Express as "an optimized
register interface, command set and feature set fo PCI Express (PCIe)-based
Solid-State Drives (SSDs)."

This commit adds nvme(4) and nvd(4) driver source code and Makefiles
to the tree.

Full NVMe functionality description:
Add nvme(4) and nvd(4) drivers and nvmecontrol(8) for NVM Express (NVMe)
device support.

There will continue to be ongoing work on NVM Express support, but there
is more than enough to allow for evaluation of pre-production NVM Express
devices as well as soliciting feedback. Questions and feedback are welcome.

nvme(4) implements NVMe hardware abstraction and is a provider of NVMe
namespaces. The closest equivalent of an NVMe namespace is a SCSI LUN.
nvd(4) is an NVMe consumer, surfacing NVMe namespaces as GEOM disks.
nvmecontrol(8) is used for NVMe configuration and management.

The following are currently supported:
nvme(4)
- full mandatory NVM command set support
- per-CPU IO queues (enabled by default but configurable)
- per-queue sysctls for statistics and full command/completion queue
dumps for debugging
- registration API for NVMe namespace consumers
- I/O error handling (except for timeoutsee below)
- compilation switches for support back to stable-7

nvd(4)
- BIO_DELETE and BIO_FLUSH (if supported by controller)
- proper BIO_ORDERED handling

nvmecontrol(8)
- devlist: list NVMe controllers and their namespaces
- identify: display controller or namespace identify data in
human-readable or hex format
- perftest: quick and dirty performance test to measure raw
performance of NVMe device without userspace/physio/GEOM
overhead

The following are still work in progress and will be completed over the
next 3-6 months in rough priority order:
- complete man pages
- firmware download and activation
- asynchronous error requests
- command timeout error handling
- controller resets
- nvmecontrol(8) log page retrieval

This has been primarily tested on amd64, with light testing on i386. I
would be happy to provide assistance to anyone interested in porting
this to other architectures, but am not currently planning to do this
work myself. Big-endian and dmamap sync for command/completion queues
are the main areas that would need to be addressed.

The nvme(4) driver currently has references to Chatham, which is an
Intel-developed prototype board which is not fully spec compliant.
These references will all be removed over time.

Sponsored by: Intel
Contributions from: Joe Golio/EMC <joseph dot golio at emc dot com>