The NVMe standard (1.4) states
>>> 8.6 Doorbell Stride for Software Emulation
>>> The doorbell stride,...is useful in software emulation of an NVM
>>> Express controller. ... For hardware implementations of the NVM
>>> Express interface, the expected doorbell stride value is 0h.
However, hardware in the wild exists with a doorbell stride of 1
(meaning 8 byte separation). This change supports that hardware, as
well as software emulators as envisioned in Section 8.6. Since this is
the fast path, care has been taken to make this computation
efficient. The bit of math to compute an offset for each is replaced
by a memory load from cache of a pre-computed value.
MFC After: 3 days
Reviewed by: scottl@
Differential Revision: https://reviews.freebsd.org/D21514
When we suspend, we need to properly shutdown the NVME controller. The
controller may go into D3 state (or may have the power removed), and
to properly flush the metadata to non-volatile RAM, we must complete a
normal shutdown. This consists of deleting the I/O queues and setting
the shutodown bit. We have to do some extra stuff to make sure we
reset the software state of the queues as well.
On resume, we have to reset the card twice, for reasons described in
the attach funcion. Once we've done that, we can restart the card. If
any of this fails, we'll fail the NVMe card, just like we do when a
reset fails.
Set is_resetting for the duration of the suspend / resume. This keeps
the reset taskqueue from running a concurrent reset, and also is
needed to prevent any hw completions from queueing more I/O to the
card. Pass resetting flag to nvme_ctrlr_start. It doesn't need to get
that from the global state of the ctrlr. Wait for any pending reset to
finish. All queued I/O will get sent to the hardware as part of
nvme_ctrlr_start(), though the upper layers shouldn't send any
down. Disabling the qpairs is the other failsafe to ensure all I/O is
queued.
Rename nvme_ctrlr_destory_qpairs to nvme_ctrlr_delete_qpairs to avoid
confusion with all the other destroy functions. It just removes the
queues in hardware, while the other _destroy_ functions tear down
driver data structures.
Split parts of the hardware reset function up so that I can
do part of the reset in suspsend. Split out the software disabling
of the qpairs into nvme_ctrlr_disable_qpairs.
Finally, fix a couple of spelling errors in comments related to
this.
Relnotes: Yes
MFC After: 1 week
Reviewed by: scottl@ (prior version)
Differential Revision: https://reviews.freebsd.org/D21493
polling within a second. Panic if we don't. All the commands that use this
interface should typically complete within a few tens to hundreds of
microseconds. Panic rather than return ETIMEDOUT because if the command somehow
does later complete, it will randomly corrupt memory. Also, it helps to get a
traceback from where the unexpected failure happens, rather than an infinite
loop.
dump support code, move the while loop into an inline function. These aren't
done in the fast path, so if the compiler choses to not inline, any performance
hit is tiny.
polled interface. Normally this would have the potential to corrupt stack memory
because the completion routines would run after we return. In this case,
however, we're doing a dump so it's safe for reasons explained in the comment.
While it worked with the kenrel, it wasn't working with the loader.
It failed to handle dependencies correctly. The reason for that is
that we never created a nvme module with the DRIVER_MODULE, but
instead a nvme_pci and nvme_ahci module. Create a real nvme module
that nvd can be dependent on so it can import the nvme symbols it
needs from there.
Arguably, nvd should just be a simple child of nvme, but transitioning
to that (and winning that argument given why it was done this way) is
beyond the scope of this change.
Reviewed by: jhb@
Differential Revision: https://reviews.freebsd.org/D21382
queues, don't try to tear them down in the ctrlr_destroy
path. Otherwise, we dereference queue structures that are NULL and we
trap.
This fix is incomplete: we leak IRQ and MSI resources when this
happens. That's preferable to a crash but still should be fixed.
load and people who pull in nvme/nvd from modules can't load nvd.ko
since it depends on nvme, not nvme_foo. The duplicate doesn't matter
since kldxref properly handles that case.
Turn off bus master after we detach the device (to match the prior
order). Release MSI after we're done detaching and have turned off
all the interrupts. Otherwise this may cause problems as other threads
race nvme_detach. This more closely matches the old order.
Reviewed by: mav@
Intel has created RST and many laptops from vendors like Lenovo and Asus. It's a
mechanism for creating multiple boot devices under windows. It effectively hides
the nvme drive inside of the ahci controller. The details are supposed to be a
trade secret. However, there's a reverse engineered Linux driver, and this
implements similar operations to allow nvme drives to attach. The ahci driver
attaches nvme children that proxy the remapped resources to the child. nvme_ahci
is just like nvme_pci, except it doesn't do the PCI specific things. That's
moved into ahci where appropriate.
When the nvme drive is remapped, MSI-x interrupts aren't forwarded (the linux
driver doesn't know how to use this either). INTx interrupts are used
instead. This is suboptimal, but usually sufficient for the laptops these parts
are in.
This is based loosely on https://www.spinics.net/lists/linux-ide/msg53364.html
submitted, but not accepted by, Linux. It was written by Dan Williams. These
changes were written from scratch by Olivier Houchard.
Submitted by: cognet@ (Olivier Houchard)
Nvme drives can be attached in a number of different ways. Separate out the PCI
attachment so that we can have other attachment types, like ahci and various
types of NVMeoF.
Submitted by: cognet@
If device is unplugged from the system (CSTS register reads return
0xffffffff), it makes no sense to send any more recovery requests or
expect any responses back. If there is a detach call in such state,
just stop all activity and free resources. If there is no detach
call (hot-plug is not supported), rely on normal timeout handling,
but when it trigger controller reset, do not wait for impossible and
quickly report failure.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
This fixes possible double call of fail_fn, for example on hot removal.
It also allows ctrlr_fn to safely return NULL cookie in case of failure
and not get useless ns_fn or fail_fn call with NULL cookie later.
MFC after: 2 weeks
Namespace Optimal I/O Boundary field added in NVMe 1.3 and Namespace
Preferred Write Granularity added in 1.4 allow upper layers to align
I/Os for improved SSD performance and endurance.
I don't have hardware reportig those yet, but NPWG could probably be
reported by bhyve.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
NVMe reservations are quite alike to SCSI persistent reservations and
can be used in clustered setups with shared multiport storage.
MFC after: 10 days
Relnotes: yes
Sponsored by: iXsystems, Inc.
In particular: Changed Namespace List, Commands Supported and Effects,
Reservation Notification, Sanitize Status.
Add few new arguments to `nvmecontrol log` subcommand.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
While very useful by itself, it also makes `nvmecontrol` not depend on
hardcoded device names parsing, that in its turn makes simple to take
nvdX (and potentially any other) device names as arguments.
Also added IOCTL bypass from nvdX to respective nvmeYnsZ makes them
interchangeable for management purposes.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
The timeout field in the CAPS register is defined to be 8 bits, so its type was
uint8_t. We recently started adding 1 to it to cope with rogue devices that
listed 0 timeout time (which is impossible). However, in so doing, other devices
that list 0xff (for a 2 minute timeout) were broken when adding 1
overflowed. Widen the type to be uint32_t like its source register to avoid the
issue.
Reported by: bapt@
While we print failure messages on the console, sometimes logs are lost or
overwhelmed. Keeping a count of how many times we've failed retriable commands
helps get a magnitude of the problem.
Retried commands can indicate a performance degredation of an nvme drive. Keep
track of the number of retries and report it out via sysctl, just like number of
commands an interrupts.
Also convert it to a bool. While the rest of the driver isn't yet bool clean,
this will help.
Reviewed by: cem@
Differential Revision: https://reviews.freebsd.org/D20988
The nvme drive dumps only the most relevant details about a command when it
fails. However, there are times this is not sufficient (such as debugging weird
issues for a new drive with a vendor). Setting hw.nvme.verbose_cmd_dump=1
in loader.conf will enable more complete debugging information about each
command that fails.
Reviewed by: rpokala
Sponsored by: Netflix
Differential Version: https://reviews.freebsd.org/D20988
These macros make places where we extract these easier to read. The shift and
mask stuff is also a bit tedious and error prone. Start with the CAP_LO and
CAP_HI registers since their scope is somewhat constrained. This is style
chagne only, no functional changes.
Reviewed by: chuck
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20979
Neither the 1.3 or 1.4 standards say this number is 1's based, but adding 1
costs little and copes with those NVMe drives that report '0' in this field
cheaply. This is consistent with what the Linux driver does as well.
Differentiate between PCI Express Endpoint devices and Root Complex
Integrated Endpoints in the nda driver. The Link Status and Capability
registers are not valid for Integrated Endpoints and should not be
displayed. The bhyve emulated NVMe device will advertise as being an
Integrated Endpoint.
Reviewed by: imp
Approved byL imp (mentor)
Differential Revision: https://reviews.freebsd.org/D20282
completions are not in a consistent state. Cope with the different
places the normal I/O completion polling thread can be interrupted and
then re-entered during a kernel panic + dump.
Reviewed by: jhb and markj (both prior versions)
Differential Revision: https://reviews.freebsd.org/D20478
Maintain symmetry with nvme_ctrlr_create_qpairs, making it easier to
match init/uninit scenarios.
Signed-off-by: John Meneghini <johnm@netapp.com>
Submitted by: Michael Hordijk <hordijk@netapp.com>
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D19781
retries.
When resetting the controller, we abort I/O. Prior to this fix, we
printed a ton of abort messages for I/O that we're going to
retry. This imparts no useful information. Stop printing them unless
our retry count is exhausted. Clarify code for when we don't retry,
and remove useless arg to a routine that's always called with it
as 'true'. All the other debug is still printed (including multiple
reset messages if we have multiple timeouts before the taskqueue
runs the actual reset) so that we know when we reset.
Reviewed by: jimharris@, chuck@
Differential Revision: https://reviews.freebsd.org/D19431
supporting older kernels. However, all supported versions of FreeBSD
have unmapped I/Os (as do several that have gone EOL), remove it. It's
unlikely the driver would work on the older kernels anyway at this
point.
supported in years. A number of changes have been made to the driver
that likely wouldn't work on those older versions that aren't properly
ifdef'd and it's project policy to GC such code once it is stale.
Use recent best practices for Copyright form at the top of
the license:
1. Remove all the All Rights Reserved clauses on our stuff. Where we
piggybacked others, use a separate line to make things clear.
2. Use "Netflix, Inc." everywhere.
3. Use a single line for the copyright for grep friendliness.
4. Use date ranges in all places for our stuff.
Approved by: Netflix Legal (who gave me the form), adrian@ (pmc files)
o In vm_pager_bufferinit() create pbuf_zone and start accounting on how many
pbufs are we going to have set.
In various subsystems that are going to utilize pbufs create private zones
via call to pbuf_zsecond_create(). The latter calls uma_zsecond_create(),
and sets a limit on created zone. After startup preallocate pbufs according
to requirements of all pbuf zones.
Subsystems that used to have a private limit with old allocator now have
private pbuf zones: md(4), fusefs, NFS client, smbfs, VFS cluster, FFS,
swap, vnode pager.
The following subsystems use shared pbuf zone: cam(4), nvme(4), physio(9),
aio(4). They should have their private limits, but changing that is out of
scope of this commit.
o Fetch tunable value of kern.nswbuf from init_param2() and while here move
NSWBUF_MIN to opt_param.h and eliminate opt_swap.h, that was holding only
this option.
Default values aren't touched by this commit, but they probably should be
reviewed wrt to modern hardware.
This change removes a tight bottleneck from sendfile(2) operation, that
uses pbufs in vnode pager. Other pagers also would benefit from faster
allocation.
Together with: gallatin
Tested by: pho
Dell-branded Intel P4600 NVMe drives benefit from NVMe 1.3's NOIOB
feature. Unfortunately just like Intel DC P4500s, they don't advertise
themselves as benefiting from this...
This changes adds P4600s to the existing list of old drives which
benefit from striping.
PR: 233969
Submitted by: David Fugate <dave.fugate@gmail.com>
Reviewed by: imp, mav
Approved by: imp (mentor)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D18772
CAM does not require SIM lock since FreeBSD 10.4, and NVMe code never
required it at all, using per-queue locks instead. This formally allows
parallel request submission in CAM mode as much as single per-device and
per-queue locks of CAM allow.
MFC after: 1 month
In the nda(4) driver, only set DISKFLAG_CANDELETE (a.k.a. can support
BIO_DELETE) if the drive supports Dataset Management. There are reports
that without this check, VMWare Workstation does not work reliably.
Fix is to check the ONCS field in the NVMe Controller Data structure for
support. This check previously existed but did not survive the
big-endian changes.
Reported by: yuripv@yuripv.net
Reviewed by: imp, mav, jimharris
Approved by: imp (mentor)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D18493
At least one NVMe drive has a bug that makeing the Command Time Out
PCIe feature unreliable. The workaround is to disable this
feature. The driver wouldn't deal correctly with a timeout anyway.
Only do this for drives that are known bad.
Sponsored by: Netflix, Inc
Differential Revision: https://reviews.freebsd.org/D17708
The original NVMe API used bit-fields to represent fields in data
structures defined by the specification (e.g. the op-code in the command
data structure). The implementation targeted x86_64 processors and
defined the bit fields for little endian dwords (i.e. 32 bits).
This approach does not work as-is for big endian architectures and was
changed to use a combination of bit shifts and masks to support PowerPC.
Unfortunately, this changed the NVMe API and forces #ifdef's based on
the OS revision level in user space code.
This change reverts to something that looks like the original API, but
it uses bytes instead of bit-fields inside the packed command structure.
As a bonus, this works as-is for both big and little endian CPU
architectures.
Bump __FreeBSD_version to 1200081 due to API change
Reviewed by: imp, kbowling, smh, mav
Approved by: imp (mentor)
Differential Revision: https://reviews.freebsd.org/D16404
Summary:
Some architectures, in this case powerpc64, need explicit synchronization
barriers vs device accesses.
Prior to this change, when running 'make buildworld -j72' on a 18-core
(72-thread) POWER9, I would see controller resets often. With this change, I
don't see these resets messages, though another tester still does, for yet to be
determined reasons, so this may not be a complete fix. Additionally, I see a
~5-10% speed up in buildworld times, likely due to not needing to reset the
controller.
Reviewed By: jimharris
Differential Revision: https://reviews.freebsd.org/D16570