Commit Graph

4 Commits

Author SHA1 Message Date
Jim Harris
0f71ecf741 Add ability to queue nvme_request objects if no nvme_trackers are available.
This eliminates the need to manage queue depth at the nvd(4) level for
Chatham prototype board workarounds, and also adds the ability to
accept a number of requests on a single qpair that is much larger
than the number of trackers allocated.

Sponsored by:	Intel
2012-10-18 00:45:53 +00:00
Jim Harris
9eb93f2976 Add return codes to all functions used for submitting commands to I/O
queues.

Sponsored by:	Intel
2012-10-18 00:32:07 +00:00
Jim Harris
be4dcf1bfa Add __aligned(4) to NVMe defined data structures.
This fixes issue in nvmecontrol(8), where clang throws a cast-align
warning when casting a __packed structure pointer to a uint32_t
pointer as part of printing raw hex output.

Reported by: dhw
2012-09-18 18:16:52 +00:00
Jim Harris
bb0ec6b359 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>
2012-09-17 19:23:01 +00:00