IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
Since we only allocate VIs for the number of TXQs we actually need, we
cannot naively use "channel * TXQ_TYPES + txq" for the TXQ number, as
this has gaps (when efx->tx_queues_per_channel < EFX_TXQ_TYPES) and
thus overruns the driver's VI allocations, causing the firmware to
reject the MC_CMD_INIT_TXQ based on INSTANCE.
Thus, we distinguish INSTANCE (stored in tx_queue->queue) from LABEL
(tx_queue->label); the former is allocated starting from 0 in
efx_set_channels(), while the latter is simply the txq type (index in
channel->tx_queue array).
To simplify things, rather than changing tx_queues_per_channel after
setting up TXQs, make Siena always probe its HIGHPRI queues at start
of day, rather than deferring it until tc mqprio enables them.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Siena needs four TX queues (csum * highpri), EF10 needs two (csum),
and EF100 only needs one (as checksumming is controlled entirely by
the transmit descriptor). Rather than having various bits of ad-hoc
code to decide which queues to set up etc., put the knowledge of how
many TXQs a channel has in one place.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All NICs supported by this driver are capable of MSI-X interrupts (only
Falcon A1 wasn't, and that's now hived off into its own driver), so no
need for a nic-type parameter. Besides, the code that checked it was
buggy anyway (the following assignment that checked min_interrupt_mode
overrode it).
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unprivileged functions (such as VFs) may set their MTU by use of the
'control' field of MC_CMD_SET_MAC_EXT, as used in efx_mcdi_set_mtu().
If calling efx_ef10_mac_reconfigure() from efx_change_mtu(), and the
NIC supports the above (SET_MAC_ENHANCED capability), use it rather
than efx_mcdi_set_mac().
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
EF100 needs to map multiple BARs (sequentially, not concurrently) in
order to read the Function Control Window during probe.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Calculate efx->max_vis at probe time, and check against it in
efx_allocate_msix_channels() when considering whether to create XDP TX
channels.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of having efx_mcdi_print_fwver() look at efx_nic_rev and
conditionally poke around inside ef10-specific nic_data, add a new
efx->type->print_additional_fwver() method to do this work.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Common code in mcdi_filters.c uses these flags, so by moving them to
either struct efx_nic (in the case of must_realloc_vis) or struct
efx_mcdi_filter_table (for must_restore_rss_contexts and
must_restore_filters), decouple this code from ef10's nic_data.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Various MCDI functions (especially in filter handling) need to check the
datapath caps, but those live in nic_data (since they don't exist on
Siena). Decouple from ef10-specific data structures by adding check_caps
to the nic_type, to allow using these functions from non-ef10 drivers.
Also add a convenience macro efx_has_cap() to reduce the amount of
boilerplate involved in calling it.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove some usage of ef10-specific nic_data structs from common MCDI
functions, in preparation for using them from a non-EF10 driver.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
XDP-redirect is broken in this driver sfc. XDP_REDIRECT requires
tailroom for skb_shared_info when creating an SKB based on the
redirected xdp_frame (both in cpumap and veth).
The fix requires some initial explaining. The driver uses RX page-split
when possible. It reserves the top 64 bytes in the RX-page for storing
dma_addr (struct efx_rx_page_state). It also have the XDP recommended
headroom of XDP_PACKET_HEADROOM (256 bytes). As it doesn't reserve any
tailroom, it can still fit two standard MTU (1500) frames into one page.
The sizeof struct skb_shared_info in 320 bytes. Thus drivers like ixgbe
and i40e, reduce their XDP headroom to 192 bytes, which allows them to
fit two frames with max 1536 bytes into a 4K page (192+1536+320=2048).
The fix is to reduce this drivers headroom to 128 bytes and add the 320
bytes tailroom. This account for reserved top 64 bytes in the page, and
still fit two frame in a page for normal MTUs.
We must never go below 128 bytes of headroom for XDP, as one cacheline
is for xdp_frame area and next cacheline is reserved for metadata area.
Fixes: eb9a36be7f3e ("sfc: perform XDP processing on received packets")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We now ignore the "completion" event when using tx queue timestamping,
and only pay attention to the two (high and low) timestamp events. The
NIC will send a pair of timestamp events for every packet transmitted.
The current firmware may merge the completion events, and it is possible
that future versions may reorder the completion and timestamp events.
As such the completion event is not useful.
Without this patch in place a merged completion event on a queue with
timestamping will cause a "spurious TX completion" error. This affects
SFN8000-series adapters.
Signed-off-by: Tom Zhao <tzhao@solarflare.com>
Acked-by: Martin Habets <mhabets@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Martin Habets <mhabets@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Includes a couple of filtering functions and also renames a constant.
Style fixes included.
Signed-off-by: Alexandru-Mihai Maftei <amaftei@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
New headers contain prototypes of functions that will be common between
ef10 and upcoming driver.
Removed static modifier from the affected functions.
Some function prototypes were removed from existing headers.
Signed-off-by: Alexandru-Mihai Maftei <amaftei@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only the SFC4000 code, now moved to sfc-falcon, needed I2C.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It was possible for channel allocation logic to get confused between what
it had and what it wanted, and end up trying to use the same channel for
both PTP and regular TX. This led to a kernel panic:
BUG: unable to handle page fault for address: 0000000000047635
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP PTI
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 5.4.0-rc3-ehc14+ #900
Hardware name: Dell Inc. PowerEdge R710/0M233H, BIOS 6.4.0 07/23/2013
RIP: 0010:native_queued_spin_lock_slowpath+0x188/0x1e0
Code: f3 90 48 8b 32 48 85 f6 74 f6 eb e8 c1 ee 12 83 e0 03 83 ee 01 48 c1 e0 05 48 63 f6 48 05 c0 98 02 00 48 03 04 f5 a0 c6 ed 81 <48> 89 10 8b 42 08 85 c0 75 09 f3 90 8b 42 08 85 c0 74 f7 48 8b 32
RSP: 0018:ffffc90000003d28 EFLAGS: 00010006
RAX: 0000000000047635 RBX: 0000000000000246 RCX: 0000000000040000
RDX: ffff888627a298c0 RSI: 0000000000003ffe RDI: ffff88861f6b8dd4
RBP: ffff8886225c6e00 R08: 0000000000040000 R09: 0000000000000000
R10: 0000000616f080c6 R11: 00000000000000c0 R12: ffff88861f6b8dd4
R13: ffffc90000003dc8 R14: ffff88861942bf00 R15: ffff8886150f2000
FS: 0000000000000000(0000) GS:ffff888627a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000047635 CR3: 000000000200a000 CR4: 00000000000006f0
Call Trace:
<IRQ>
_raw_spin_lock_irqsave+0x22/0x30
skb_queue_tail+0x1b/0x50
sock_queue_err_skb+0x9d/0xf0
__skb_complete_tx_timestamp+0x9d/0xc0
efx_dequeue_buffer+0x126/0x180 [sfc]
efx_xmit_done+0x73/0x1c0 [sfc]
efx_ef10_ev_process+0x56a/0xfe0 [sfc]
? tick_sched_do_timer+0x60/0x60
? timerqueue_add+0x5d/0x70
? enqueue_hrtimer+0x39/0x90
efx_poll+0x111/0x380 [sfc]
? rcu_accelerate_cbs+0x50/0x160
net_rx_action+0x14a/0x400
__do_softirq+0xdd/0x2d0
irq_exit+0xa0/0xb0
do_IRQ+0x53/0xe0
common_interrupt+0xf/0xf
</IRQ>
In the long run we intend to rewrite the channel allocation code, but for
'net' fix this by allocating extra_channels, and giving them TX queues,
even if we do not in fact need them (e.g. on NICs without MAC TX
timestamping), and thereby using simpler logic to assign the channels
once they're allocated.
Fixes: 3990a8fffbda ("sfc: allocate channels for XDP tx queues")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If there's no traffic on a channel, its ARFS expiry work will never get
scheduled by efx_poll() as that isn't being run.
So make efx_filter_rfs_expire() reschedule itself to run after 30 seconds.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Report the number of successful and failed insertions, and also the
current count of filters, to aid in tuning e.g. rps_flow_cnt.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
The old rfs_filters_added method for determining the quota could potentially
allow the NIC to become filled with old filters, which never get tested for
expiry. Instead, explicitly make expiry check work depend on the number of
filters installed, and don't count checking slots without filters in as
doing work. This guarantees that each filter will be checked for expiry at
least once every thirty seconds (assuming the channel to which it belongs is
NAPI polling actively) regardless of fill level.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Tested-by: David Ahern <dahern@digitalocean.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Count XDP packet drops, error drops, transmissions and redirects and
expose these counters via the ethtool stats command.
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Each CPU needs access to its own queue to allow uncontested
transmission of XDP_TX packets. This means we need to allocate (up
front) enough channels ("xdp transmit channels") to provide at least
one extra tx queue per CPU. These tx queues should not do TSO.
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds a field to hold an attached xdp_prog, but never populates it (see
following patch). Also, XDP_TX support is deferred to a later patch
in the series.
Track failures of xdp_rxq_info_reg() via per-queue xdp_rxq_info_valid
flags and a per-nic xdp_rxq_info_failed flag. The per-queue flags are
needed to prevent attempts to xdp_rxq_info_unreg() structs that failed
to register. Possibly the API could be changed in the future to avoid
the need for these flags.
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a field to efx_tx_buffer so that we can track xdp_frames. Add a
flag so that buffers that contain xdp_frames can be identified and
passed to xdp_return_frame.
Signed-off-by: Charles McLachlan <cmclachlan@solarflare.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Improves packet rate of 1-byte UDP receives by up to 10%.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Associate an arbitrary ID with each ARFS filter, allowing to properly query
for expiry. The association is maintained in a hash table, which is
protected by a spinlock.
v3: fix build warnings when CONFIG_RFS_ACCEL is disabled (thanks lkp-robot).
v2: fixed uninitialised variable (thanks davem and lkp-robot).
Fixes: 3af0f34290f6 ("sfc: replace asynchronous filter operations")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A misconfigured system (e.g. with all interrupts affinitised to all CPUs)
may produce a storm of ARFS steering events. With the existing sfc ARFS
implementation, that could create a backlog of workitems that grinds the
system to a halt. To prevent this, limit the number of workitems that
may be in flight for a given SFC device to 8 (EFX_RPS_MAX_IN_FLIGHT), and
return EBUSY from our ndo_rx_flow_steer method if the limit is reached.
Given this limit, also store the workitems in an array of slots within the
struct efx_nic, rather than dynamically allocating for each request.
The limit should not negatively impact performance, because it is only
likely to be hit in cases where ARFS will be ineffective anyway.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise races are possible between ethtool ops and
efx_ef10_rx_restore_rss_contexts().
Also, don't try to perform the restore on every reset, only after an MC
reboot, otherwise we'll leak RSS contexts on the NIC.
Fixes: 42356d9a137b ("sfc: support RSS spreading of ethtool ntuple filters")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With this change, the spinlock efx->filter_lock is no longer used and is
thus removed.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
efx->filter_lock remains in place for use on farch, but EF10 now ignores it.
EFX_EF10_FILTER_FLAG_BUSY is no longer needed, hence it is removed.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of having an efx->type->filter_rfs_insert() method, just use
workitems with a worker function that calls efx->type->filter_insert().
The only user of this is efx_filter_rfs(), which now queues a call to
efx_filter_rfs_work().
Similarly, efx_filter_rfs_expire() is now a worker function called on a
new channel->filter_work work_struct, so the method
efx->type->filter_rfs_expire_one() is no longer called in atomic context.
We also add a new mutex efx->rps_mutex to protect the RPS state (efx->
rps_expire_channel, efx->rps_expire_index, and channel->rps_flow_id) so
that the taking of efx->filter_lock can be moved to
efx->type->filter_rfs_expire_one().
Thus, all filter table functions are now called in a sleepable context,
allowing them to use sleeping locks in a future patch.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As well as 'auto' and the forced 'off', 'rs' and 'baser' states, we also
handle combinations of settings (since the fecparam->fec field is a
bitmask), where auto|rs and auto|baser specify a preferred FEC mode but
will fall back to the other if the cable or link partner doesn't support
it. rs|baser (with or without auto bit) means prefer FEC even where
auto wouldn't use it, but let FW choose which encoding to use.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use a linked list to associate user-facing context IDs with FW-facing
context IDs (since the latter can change after an MC reset).
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For this we create and use one or more new TX queues on the PTP channel,
and enable sync events for it.
Based on a patch by Martin Habets <mhabets@solarflare.com>.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before this work, TX timestamping is done by sending each SKB to the MC.
On the 8000 series (Medford1) we have high speed timestamping via the
MAC, which means we can use normal TX queues for this without a
significant drop in bandwidth. On the X2000 series (Medford2) support
for transmitting via the MC is removed, so the new way must be used.
This patch enables timestamping on a TX queue, if requested.
It also enhances TX event handling to process the extra completion events,
and puts the time in the SKB.
Signed-off-by: Martin Habets <mhabets@solarflare.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Store and handle ethtool link mode masks within the driver instead of
just a single u32. However, quite a significant amount of existing code
wants to manipulate the masks directly, and thus now uses the first
unsigned long (i.e. mask[0]) as though it were a legacy u32 mask. This
is ok because all the bits that code is interested in are in the first
32 bits of the mask; but it might be a good idea to change them in
future to use the proper bitmap API.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Medford2 NICs support more than MC_CMD_MAC_NSTATS stats, and report the new
count in a field of MC_CMD_GET_CAPABILITIES_V4. This also means that the
end generation count moves (it is, as before, the last 64 bits of the DMA
buffer, but that is no longer MC_CMD_MAC_GENERATION_END).
So read num_mac_stats from the GET_CAPABILITIES response, if present;
otherwise assume MC_CMD_MAC_NSTATS; and always use num_mac_stats - 1 rather
than MC_CMD_MAC_GENERATION_END.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Bert Kenward <bkenward@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Log a message if PTP probing fails; if we then, unexpectedly, get PTP
events, only log a message for the first one on each device.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Medford2 can also have 16k or 64k VI stride. This is reported by MCDI in
GET_CAPABILITIES, which fortunately is called before the driver does
anything sensitive to the VI stride (such as accessing or even allocating
VIs past the zeroth).
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Support using BAR 0 on SFC9250, even though the driver doesn't bind to such
devices yet.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add min_interrupt_mode specification per NIC type.
It is a bit confusing because of "highest interrupt mode is less capable".
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement ndo_udp_tunnel_{add,del} to update the NIC's list of VXLAN and
GENEVE UDP ports. Also reset the port list to empty on driver load and
on driver unload, with appropriate flag set on the unload case.
These port numbers are used for RX inner checksum offload, and in future
will also be used for TX inner checksum offload and encapsulated TSO.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set the csum_level for encapsulated packets where the encapsulation
type, l3 class and l4 class are sets that need it.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for RX checksum offload of encapsulated packets. This
essentially just means paying attention to the inner checksum flags
in the RX event, and if *either* checksum flag indicates a fail then
don't tell the kernel that checksum offload was successful.
Also, count these checksum errors and export the counts to ethtool -S.
Test the most common "good" case of RX events with a single bitmask
instead of a series of ifs. Move the more specific error checking
in to a separate function for clarity, and don't use unlikely() there
since we know at least one of the bits is bad.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In linux-4.5, busy polling was implemented in core
NAPI stack, meaning that all custom implementation can
be removed from drivers.
Not only we remove lot's of tricky code, we also remove
one lock operation in fast path.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Edward Cree <ecree@solarflare.com>
Cc: Bert Kenward <bkenward@solarflare.com>
Acked-by: Bert Kenward <bkenward@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ensures that we report the key and indirection table the NIC is using,
rather than (if setting them failed earlier) what we wanted it to use.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an option descriptor has been sent on a queue but not followed by a
packet, there will have been no completion event, so the read and write
counts won't match and we'll think we can't do PIO. This combines with
the fact that we have two TX queues (for en/disable checksum offload),
and that both must be empty for PIO to happen.
This patch adds a separate "packet_write_count" that tracks the most
recent write_count we expect to see a completion event for; this excludes
option descriptors but _includes_ PIO descriptors (even though they look
like option descriptors). This is then used, rather than write_count,
in efx_nic_tx_is_empty().
We only bother to maintain packet_write_count on EF10, since on Siena
(a) there are no option descriptors and it always equals write_count, and
(b) there's no PIO, so we don't need it anyway.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
