The e1000 drivers (em, lem, igb) are currently looking at the
iflib copies of the capabilities bitvectors (scctx->isc_capabilities
and scctx->isc_capenable) rather than the ifnet ones
(ifp->if_capabilities and ifp->if_capenable). However, the latter
are the ones that are actually updated by ifconfig and that should
be used by the drivers during interface operation. The former are
set by the driver on interface attach (for iflib internal use)
and should not be used anymore by the driver.
This patch fixes the e1000 driver to use the correct bitvectors.
PR: 260068
Reviewed by: markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D33154
This is useful for diagnosing problems. In particular, the errata
sheets identify the EEPROM version for many fixes.
Reviewed by: gallatin
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D32333
Otherwise results in KASSERT with debug kernels because we rely on the
iflib CTX lock to implement the software serialization to the NVM model
Reviewed by: gallatin
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D32333
Drop arguments of function prototypes since the file is mixed between
listing arg names and not.
No functional changes
Reviewed by: markj
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D32329
A change to MSI-X link handler was somehow causing issues on
MSI-based em(4) NICs.
Revert the change based on user reports and testing.
PR: 258551
Reported by: Franco Fichtner <franco@opnsense.org>, t_uemura@macome.co.jp
Reviewed by: markj, Franco Fichtner <franco@opnsense.org>
Tested by: t_uemura@macome.co.jp
MFC after: 1 day
Rename the 'struct adapter' to 'struct e1000_sc' to avoid type ambiguity
in things like kgdb.
Reviewed by: jhb, markj
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D32129
Add two files base.c and base.h to reduce the redundancy
in the silicon family code.
Remove the code duplication from e1000_82575 files.
Clean family specific functions from base.
Fix up a stray and duplicate function declaration.
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Signed-off-by: Guinan Sun <guinanx.sun@intel.com>
Reviewed-by: Wei Zhao <wei.zhao1@intel.com>
Approved by: imp
Obtained from: DPDK (44dddd14059f151f39f7e075b887decfc9a10f11)
MFC after: 1 week
This reverts commit fc7682b17f.
This will be done incrementally to help with bisecting an issue in
later I21x devices (ich8lan).
PR: 258153
Approved by: imp
MFC after: 1 day
* Don't reset the entire adapter for vlan changes, fix up the problems
* Add some functions for vlan filter (vfta) manipulation
* Don't muck with the vfta if we aren't doing HW vlan filtering
* Disable interrupts when manipulating vfta on lem(4)-class NICs
* On the I350 there is a specification update (2.4.20) in which the
suggested workaround is to write to the vfta 10 times (if at first you
don't succeed, try, try again). Our shared code has the goods, use it
* Increase a VF's frame receive size in the case of vlans
From the referenced PR, this reduced vlan configuration from minutes
to seconds with hundreds or thousands of vlans and prevents wedging the
adapter with needless adapter reinitialization for each vlan ID.
PR: 230996
Reviewed by: markj
Tested by: Ozkan KIRIK <ozkan.kirik@gmail.com>
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D30002
Sync the e1000 shared code with DPDK shared code
"cid-gigabit.2020.06.05.tar.gz released by ND"
Primary focus was on client platforms (ich8lan). More work remains here
but we need an Intel contact for client networking.
Reviewed by: grehan, Intel Networking (erj, earlier rev)
Obtained from: DPDK <http://git.dpdk.org/dpdk/tree/drivers/net/e1000/base>
MFC after: 1 week
Sponsored by: me
Differential Revision: https://reviews.freebsd.org/D31547
To enable RSS hashing in the NIC, the PCSD bit must be set.
By default, this is never set when RXCSUM is disabled - which
causes problems higher up in the stack.
While here improve the RXCSUM flag assignments when enabling or
disabling IFCAP_RXCSUM.
See also: https://lists.freebsd.org/pipermail/freebsd-current/2020-May/076148.html
Reviewed by: markj, Franco Fichtner <franco@opnsense.org>,
Stephan de Wit <stephan.dewt@yahoo.co.uk>
Obtained from: OPNsense
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D31501
Co-authored-by: Stephan de Wit <stephan.dewt@yahoo.co.uk>
Co-authored-by: Franco Fichtner <franco@opnsense.org>
Simplify the setup of srrctl.BSIZEPKT on igb class NICs.
Improve the setup of rctl.BSIZE on lem and em class NICs.
Don't try to touch rfctl on lem class NICs.
Manipulate rctl.BSEX correctly on lem and em class NICs.
Approved by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D31457
* Fix 82574 Link Status Changes, carrying the OTHER mask bit around as
needed.
* Move igb-class LSC re-arming out of FAST back into the handler.
* Clarify spurious/other interrupt re-arms in FAST.
In MSI-X mode, 82574 and igb-class devices use an interrupt filter to
handle Link Status Changes. We want to do LSC re-arms in the handler
to take advantage of autoclear (EIAC) single shot behavior.
82574 uses 'Other' in ICR and IMS for LSC interrupt types when in MSI-X
mode, so we need to set and re-arm the 'Other' bit during attach and
after ICR reads in the FAST handler if not an LSC or after handling on
LSC due to autoclearing.
This work was primarily done to address the referenced PR, but inspired
some clarification and improvement for igb-class devices once the
intentions of previous bug fix attempts became clearer.
PR: 211219
Reported by: Alexey <aserp3@gmail.com>
Tested by: kbowling (I210 lagg), markj (I210)
Approved by: markj
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D29943
This is just clerical work to ease bug triage and may be used to set
expectations around the ability for anyone in the community to perform
testing and development on older parts (this driver covers over 20 years
of silicon)
Reviewed by: erj
Approved by: markj
Sponsored by: Pink Floyd - Any Colour You Like (in kind)
Differential Revision: https://reviews.freebsd.org/D29872
Add support for current and future client platform PCI IDs. These are
all I219 variants and have no known driver changes versus previous
generation client platform I219 variants.
Reviewed by: markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D29801
There are a number of issues in the e1000 multicast filter handling
that have been present for a long time. Take the updated approach from
ixgbe(4) which does not have the issues.
The issues are outlined in the PR, in particular this solves crossing
over and under the hardware's filter limit, not programming the
hardware filter when we are above its limit, disabling SBP (show bad
packets) when the tunable is enabled and exiting promiscuous mode, and
an off-by-one error in the em_copy_maddr function.
PR: 140647
Reported by: jtl
Reviewed by: markj
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D29789
Restore 525e07418c after the iflib conversion of igb(4). This
reenables random MAC address generation when attaching to a VF with a
zeroed MAC.
PR: 253535
Reported by: Balaev PA <mail@void.so>
Reviewed by: markj
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D29785
The boundary differentiating "lem" vs "em" class devices was wrong
after the iflib conversion of lem(4).
The Packet Buffer size for 82547 class chips was not set correctly
after the iflib conversion of lem(4).
These changes restore functionality on an 82547 for the submitter.
PR: 236119
Reported by: Jeff Gibbons <jgibbons@protogate.com>
Reviewed by: markj
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D29766
This is a debugging tunable that shouldn't have retained this setting
after the initial iflib conversion of the driver
PR: 248934
Reported by: Franco Fichtner <franco@opnsense.org>
Reviewed by: markj
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D29768
This structure is shared among multiple instances of a driver, so we
should ensure that it doesn't somehow get treated as if there's a
separate instance per interface. This is especially important for
software-only drivers like wg.
DEVICE_REGISTER() still returns a void * and so the per-driver sctx
structures are not yet defined with the const qualifier.
Reviewed by: gallatin, erj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D29102
Memory and PCI resources are freed with no particular order. This could
cause use-after-frees when detaching following a failed attach. For
instance, iflib_tx_structures_free() frees ctx->ifc_txqs[] but
iflib_tqg_detach() attempts to access this array. Similarly, adapter
queues gets freed by IFDI_QUEUES_FREE() but IFDI_DETACH() attempts to
access adapter queues to free PCI resources.
MFC after: 2 weeks
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D27634
It's rather confusing when adapter->hw and hw are mixed and matched
within a particular function.
Some of this was missed in cd1cf2fc1d
and r353778 respectively.
Current way, hardcoded value plus heuristic is not conform to the PCI(e)
specification and it fails on systems where MSI-X bar is not initialized by
BIOS/ACPI (many arm or arm64 systems for example).
Instead, use the standard PCI(e) capability for determining of
MSIX table bar address.
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D27265
A failure in iflib_device_register() can result in
em_free_pci_resources() being called after receive queues have already
been freed. In particular, a failure to allocate IRQ resources will goto
fail_queues, where IFDI_QUEUES_FREE() will be called via
iflib_tx_structures_free(), preceding the call to IFDI_DETACH().
Cope with this by checking adapter->rx_queues before dereferencing it.
A similar check is present in ixgbe(4) and ixl(4).
MFC after: 1 week
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D27260
From Franco:
The iflib rewrite forced the promisc flag but it was not reported
to the system. Noticed on a stock VM that went into unsolicited
promisc mode when dhclient was started during bootup.
PR: 248869
Submitted by: Franco Fichtner <franco@opnsense.org>
Reviewed by: erj@
MFC after: 3 days
The FreeBSD em driver fails to properly reset the VME flag
in the e1000 CTRL register oneg the following ifconfig command
ifconfig em1 -vlanhwtag
Tested on the e1000 device emulated by QEMU, and on a real
NIC (chip=0x10d38086).
PR: 236584
Submitted by: murat@sunnyvalley.io
Reported by: murat@sunnyvalley.io
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D25286
This partially reverts r361053 since there have been reports
by users that this breaks some functionality for em(4)
devices; it seems at first glance that some sort of interface
restart is required for those cards.
This isn't a proper fix; this unbreaks those users until a proper
fix is found for their issues.
PR: 240818
Reported by: Marek Zarychta <zarychtam@plan-b.pwste.edu.pl>
MFC after: 3 days
This change introduces Comet Lake Mobile Platform support in the e1000
driver along with shared code patches described below.
- Cast return value of e1000_ltr2ns() to higher type to avoid overflow
- Remove useless statement of assigning act_offset
- Add initialization of identification LED
- Fix flow control setup after connected standby:
After connected standby the driver blocks resets during
"AdapterStart" and skips flow control setup. This change adds
condition in e1000_setup_link_ich8lan() to always setup flow control
and to setup physical interface only when there is no need to block
resets.
Signed-off-by: Piotr Pietruszewski <piotr.pietruszewski@intel.com>
Submitted by: Piotr Pietruszewski <piotr.pietruszewski@intel.com>
Reviewed by: erj@
Tested by: Jeffrey Pieper <jeffrey.e.pieper@intel.com>
MFC after: 1 week
Relnotes: yes
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D25035
Pursuant to r360398, implement driver-specific versions of the
ifdi_needs_restart iflib device method.
Some (if not most?) Intel network cards don't need reinitializing when a
VLAN is added or removed from the device hardware, so these implement
ifdi_needs_restart in a way that tell iflib not to bring the interface
up or down when a VLAN is added or removed, regardless of whether the
VLAN_HWFILTER interface capability flag is set or not.
This could potentially solve several PRs relating to link flaps that
occur when VLANs are added/removed to devices.
Signed-off-by: Eric Joyner <erj@freebsd.org>
PR: 240818, 241785
Reviewed by: gallatin@, olivier@
MFC after: 3 days
MFC with: r360398
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D24659
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
A couple of drivers and one place in if.c use ETH_ADDR_LEN, even though
net/ethernet.h provides an equivalent ETHER_ADDR_LEN definition.
Cleanup all of the locations which refer to ETH_ADDR_LEN to use the
standard ETHER_ADDR_LEN instead.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: erj@, jpaetzel@
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D21239
- In em_msix_link(), properly handle IGB-class devices after the iflib(4)
conversion again by only setting EM_MSIX_LINK for the EM-class 82574
and by re-arming link interrupts unconditionally, i. e. not only in
case of spurious interrupts. This fixes the interface link state change
detection for the IGB-class. [1]
- In em_if_update_admin_status(), only re-arm the link state change
interrupt for 82574 and also only if such a device uses MSI-X, i. e.
takes advantage of autoclearing. In case of INTx and MSI as well as
for LEM- and IGB-class devices, re-arming isn't appropriate here and
setting EM_MSIX_LINK isn't either.
While at it, consistently take advantage of the hw variable.
PR: 236724 [1]
Differential Revision: https://reviews.freebsd.org/D21924
From Jake:
The e1000 driver sets the iflib shared context isc_pause_frames value to
the number of received xoff frames. This is done so that the iflib
watchdog timer won't trigger a Tx Hang due to pause frames.
Unfortunately, the function simply sets it to the value of the xoffrxc
counter. Once the device has received a single XOFF packet, the driver
always reports that we received pause frames. This will prevent the Tx
hang detection entirely from that point on.
Fix this by assigning isc_pause_frames to a non-zero value if we
received any XOFF packets in the last timer interval.
We could attempt to calculate the total number of received packets by
doing a subtraction, but the iflib stack only seems to check if
isc_pause_frames is non-zero.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: gallatin@
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D21868
times - on every interrupt by using an own set of device methods for the
IGB class. This translates to introducing igb_if_intr_{disable,enable}()
and igb_if_{rx,tx}_queue_intr_enable() with that IGB-specific code moved
out of their EM counterparts and otherwise continuing to use the EM IFDI
methods also for IGB.
Note that igb_if_intr_{disable,enable}() also issue E1000_WRITE_FLUSH as
lost with the conversion of igb(4) to iflib(4).
Also note, that the em_if_{disable,enable}_intr() methods are renamed to
em_if_intr_{disable,enable}() for consistency with the names used in the
interface declaration.
o In em_intr():
- Don't bother to bail out if the interrupt type is "legacy", i. e. INTx
or MSI, as iflib(4) doesn't use ift_legacy_intr methods for MSI-X. All
other iflib(4)-based drivers avoid this check, too.
- Given that only the MSI-X interrupts have one-shot behavior (by taking
advantage of the EIAC register), explicitly disable interrupts. Hence,
em_intr() now matches what {em,igb}_irq_fast() previously did (in case
of igb(4) supposedly also to work around MSI message reordering errata
on certain systems).
o In em_if_intr_disable():
- Clear the EIAC register unconditionally for 82574 and not just in case
of MSI-X, matching em_if_intr_enable() and bringing back the last hunk
of r206437 lost with the iflib(4) conversion.
- Write to EM_EIAC for clearing said register instead of to the IGB-only
E1000_EIAC used ever since the iflib(4) conversion.
Reviewed by: shurd
Differential Revision: https://reviews.freebsd.org/D20176
From Jake:
iflib_fl_setup calculates a suitable buffer size for the Rx mbufs based
on the isc_max_frame_size value that drivers setup. This calculation is
repeated by drivers when programming their hardware with the size of
each Rx buffer.
This can lead to a mismatch where the iflib mbuf size is different from
the expected size of the buffer as programmed by the hardware. This can
lead to unexpected results.
If iflib ever wants to support mbuf sizes larger than one page, every
driver must be updated to account for the new possible buffer sizes.
Fix this by calculating the mbuf size prior to calling IFDI_INIT, and
adding the iflib_get_rx_mbuf_sz function which will expose this value to
drivers, so that they do not repeat the same calculation.
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@, erj@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D19489
From Jake:
"The iflib_fl_setup() function tries to pick various buffer sizes based
on the max_frame_size value defined by the parent driver. However, this
code was wrapped under CONTIGMALLOC_WORKS, which was never actually
defined anywhere.
This same code pattern was used in if_em.c, likely trying to match
what iflib uses.
Since CONTIGMALLOC_WORKS is not defined, remove this dead code from
iflib_fl_setup and if_em.c
Given that various iflib drivers appear to be using a similar
calculation, it might be worth making this buffer size a value that the
driver can peek at in the future."
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D19199
r241119 that's performed globally by device_attach(9).
- As for the EM-class of devices, em(4) supports multiple queues
and MSI-X respectively only with 82574 devices. However, since
the conversion to iflib(4), em(4) relies on the interrupt type
fallback mechanism, i. e. MSI-X -> MSI -> INTx, of iflib(4) to
figure out the interrupt type to use for the EM-class (as well
as the IGB-class) of MACs. Moreover, despite the datasheet for
82583V not mentioning any support of MSI-X, there actually are
82583V devices out there that report a varying number of MSI-X
messages as supported. The interrupt type fallback of iflib(4)
is causing two failure modes depending on the actual number of
MSI-X messages supported for such instances of 82583V:
1) With only one MSI-X message supported, none is left for the
RX/TX queues as that one message gets assigned to the admin
interrupt. Worse, later on - which will be addressed with a
separate fix - iflib(4) interprets that one messages as MSI
or INTx to be set up, but fails to actually do so as it has
previously called pci_alloc_msix(9). [1, 2]
2) With more message supported, their distribution is okay but
then em_if_msix_intr_assign() doesn't work for 82583V, with
the interface being left in a non-working state, too. [3]
Thus, let em_if_attach_pre() indicate to iflib(4) to try MSI-X
with 82574 only, and at most MSI for the remainder of EM-class
devices.
While at it, remove "try_second_bar" as it's polarity inverted
and not actually needed.
- Remove code from em_if_timer() that effectively is a NOP since
the conversion to iflib(4) ("trigger" is no longer read).
While at it, let the comment for em_if_timer() reflect reality
after said conversion.
- Implement an ifdi_watchdog_reset method which only updates the
em(4) "watchdog_events" counter but doesn't perform any reset,
so that the em(4) "watchdog_timeouts" SYSCTL (iflib(4) doesn't
provide a counterpart) reflects reality and these timeouts add
to IFCOUNTER_OERRORS again after the iflib(4) conversion.
- Remove the "mbuf_defrag_fail" and "tx_dma_fail" SYSCTLS; since
the iflib(4) conversion, associated counters are disconnected,
but iflib(4) provides "mbuf_defrag_failed" and "tx_map_failed"
respectively as equivalents.
- Move the description preceding lem_smartspeed() to the correct
spot before em_reset() and bring back appropriate comments for
{igb,em}_initialize_rss_mapping() and lem_smartspeed() lost in
the iflib(4) conversion.
- Adapt some other function descriptions and INIT_DEBUGOUT() use
to match reality after the iflib(4) conversion.
- Put the debugging message of em_enable_vectors_82574() (missed
in r343578) under bootverbose, too.
PR: 219428 [1], 235246 [2], 235147 [3]
Reviewed by: erj (previous version)
Differential Revision: https://reviews.freebsd.org/D19108
When configured with more tx queues than rx queues,
em_if_msix_intr_assign() was incorrectly routing the tx event
interrupts.
Reviewed by: erj, marius
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19070
bus_teardown_intr(9) before pci_release_msi(9).
- Ensure that iflib(4) and associated drivers pass correct RIDs to
bus_release_resource(9) by obtaining the RIDs via rman_get_rid(9)
on the corresponding resources instead of using the RIDs initially
passed to bus_alloc_resource_any(9) as the latter function may
change those RIDs. Solely em(4) for the ioport resource (but not
others) and bnxt(4) were using the correct RIDs by caching the ones
returned by bus_alloc_resource_any(9).
- Change the logic of iflib_msix_init() around to only map the MSI-X
BAR if MSI-X is actually supported, i. e. pci_msix_count(9) returns
> 0. Otherwise the "Unable to map MSIX table " message triggers for
devices that simply don't support MSI-X and the user may think that
something is wrong while in fact everything works as expected.
- Put some (mostly redundant) debug messages emitted by iflib(4)
and em(4) during attachment under bootverbose. The non-verbose
output of em(4) seen during attachment now is close to the one
prior to the conversion to iflib(4).
- Replace various variants of spelling "MSI-X" (several in messages)
with "MSI-X" as used in the PCI specifications.
- Remove some trailing whitespace from messages emitted by iflib(4)
and change them to consistently start with uppercase.
- Remove some obsolete comments about releasing interrupts from
drivers and correct a few others.
Reviewed by: erj, Jacob Keller, shurd
Differential Revision: https://reviews.freebsd.org/D18980
From Jake:
In r341156 ("Fix first-packet completion", 2018-11-28) a hack to work
around a delta calculation determining how many descriptors were used
was added to ixl_isc_tx_credits_update_dwb.
The same fix was also applied to the em and igb drivers in r340310, and
to ix in r341156.
The hack checked the case where prev and cur were equal, and then added
one. This works, because by the time we do the delta check, we already
know there is at least one packet available, so the delta should be at
least one.
However, it's not a complete fix, and as indicated by the comment is
really a hack to work around the real bug.
The real problem is that the first time that we transmit a packet,
tx_cidx_processed will be set to point to the start of the ring.
Ultimately, the credits_update function expects it to point to the
*last* descriptor that was processed. Since we haven't yet processed any
descriptors, pointing it to 0 results in this incorrect calculation.
Fix the initialization code to have it point to the end of the ring
instead. One way to think about this, is that we are setting the value
to be one prior to the first available descriptor.
Doing so, corrects the delta calculation in all cases. The original fix
only works if the first packet has exactly one descriptor. Otherwise, we
will report 1 less than the correct value.
As part of this fix, also update the MPASS assertions to match the real
expectations. First, ensure that prev is not equal to cur, since this
should never happen. Second, remove the assertion about prev==0 || delta
!= 0. It looks like that originated from when the em driver was
converted to iflib. It seems like it was supposed to ensure that delta
was non-zero. However, because we originally returned 0 delta for the
first calculation, the "prev == 0" was tacked on.
Instead, replace this with a check that delta is greater than zero,
after the correction necessary when the ring pointers wrap around.
This new solution should fix the same bug as r341156 did, but in a more
robust way.
Submitted by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed by: shurd@
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D18545
These messages are totally redundant with the iflib messages.
They're also not very useful, since they don't include the
interface name.
Discussed with: shurd
Approved by: re (rgrimes)
Sponsored by: Dell EMC Isilon
