The original issue being fixed in this patch was seen with the ixgbe
driver, but the same issue exists with igb as well, as the code is
very similar. read_barrier_depends is not sufficient to ensure
loads following it are not speculatively loaded out of order
by the CPU, which can result in stale data being loaded, causing
potential system crashes.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Acked-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Change TC_SETUP_CBS to TC_SETUP_QDISC_CBS to match the new convention..
Signed-off-by: NNogah Frankel <nogahf@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds support for Credit-Based Shaper (CBS) qdisc offload
from Traffic Control system. This support enable us to leverage the
Forwarding and Queuing for Time-Sensitive Streams (FQTSS) features
from Intel i210 Ethernet Controller. FQTSS is the former 802.1Qav
standard which was merged into 802.1Q in 2014. It enables traffic
prioritization and bandwidth reservation via the Credit-Based Shaper
which is implemented in hardware by i210 controller.

The patch introduces the igb_setup_tc() function which implements the
support for CBS qdisc hardware offload in the IGB driver. CBS offload
is the only traffic control offload supported by the driver at the
moment.

FQTSS transmission mode from i210 controller is automatically enabled
by the IGB driver when the CBS is enabled for the first hardware
queue. Likewise, FQTSS mode is automatically disabled when CBS is
disabled for the last hardware queue. Changing FQTSS mode requires NIC
reset.

FQTSS feature is supported by i210 controller only.
Signed-off-by: NAndre Guedes <andre.guedes@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Tested-by: NHenrik Austad <henrik@austad.us>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

When the driver cannot map a TX buffer, instead of rolling back
gracefully and retrying later, we currently get a panic:

[  159.885994] igb 0000:00:00.0: TX DMA map failed
[  159.886588] Unable to handle kernel paging request at virtual address ffff00000a08c7a8
               ...
[  159.897031] PC is at igb_xmit_frame_ring+0x9c8/0xcb8

Fix the erroneous test that leads to this situation.
Signed-off-by: NJean-Philippe Brucker <jean-philippe.brucker@arm.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()

Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Switches test of .data field to
.function, since .data will be going away.

Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: intel-wired-lan@lists.osuosl.org
Cc: netdev@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check memory allocation failures and return -ENOMEM in such cases, as
already done for other memory allocations in this function.

This avoids NULL pointers dereference.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Tested-by: Aaron Brown <aaron.f.brown@intel.com
Acked-by: NPJ Waskiewicz <peter.waskiewicz.jr@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The management port on an Edgecore AS7712-32 switch uses an igb MAC, but
it uses a BCM54616 PHY. Without a patch like this, loading the igb
module produces dmesg output like this:

[    3.439125] igb: Copyright (c) 2007-2014 Intel Corporation.
[    3.439866] igb: probe of 0000:00:14.0 failed with error -2
Signed-off-by: NJohn W Linville <linville@tuxdriver.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

When the PF receives a mailbox message from the VF, it grabs the mailbox
lock, reads the VF message from the mailbox, ACKs the message and drops
the lock.

While the PF is performing the action for the VF message, nothing
prevents another VF message from being posted to the mailbox.  The
current code handles this condition by just dropping any new VF messages
without processing them.  This results in a mailbox timeout in the VM
for posted messages waiting for an ACK, and the VF is reset by the
igbvf_watchdog_task in the VM.

Given the right sequence of VF messages and mailbox timeouts, this
condition can go on ad infinitum.

Modify the PF mailbox read method to take an 'unlock' argument that
optionally leaves the mailbox locked by the PF after reading the VF
message.  This ensures another VF message is not posted to the mailbox
until after the PF has completed processing the VF message and written
its reply.
Signed-off-by: NGreg Edwards <gedwards@ddn.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add a mailbox unlock method to e1000_mbx_operations, which will be used
to unlock the PF/VF mailbox by the PF.
Signed-off-by: NGreg Edwards <gedwards@ddn.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Signed-off-by: NGreg Edwards <gedwards@ddn.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

TSAUXC.DisableSystime is never set, so SYSTIM runs into a SYS WRAP
every 1100 secs on 80580/i350/i354 (40 bit SYSTIM) and every 35000
secs on 80576 (45 bit SYSTIM).

This wrap event sets the TSICR.SysWrap bit unconditionally.

However, checking TSIM at interrupt time shows that this event does not
actually cause the interrupt.  Rather, it's just bycatch while the
actual interrupt is caused by, for instance, TSICR.TXTS.

The conclusion is that the SYS WRAP is actually expected, so the
"unexpected SYS WRAP" message is entirely bogus and just helps to
confuse users.  Drop it.
Signed-off-by: NCorinna Vinschen <vinschen@redhat.com>
Acked-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

HW timestamping can only be requested for a packet if the NIC is first
setup via ioctl(SIOCSHWTSTAMP). If this step was skipped, then the igb
driver still allowed TX packets to request HW timestamping. In this
situation, the _IGB_PTP_TX_IN_PROGRESS flag was set and would never
clear. This prevented any future HW timestamping requests to succeed.

Fix this by checking that the NIC is configured for HW TX timestamping
before accepting a HW TX timestamping request.
Signed-off-by: NCliff Spradlin <cspradlin@google.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

After add an ethertype filter, if user change the adapter speed several
times, the error "ethtool -N: etype filters are all used" is reported by
igb driver.

In older patch, function igb_nfc_filter_exit() and igb_nfc_filter_restore()
is not paried. igb_nfc_filter_restore() exist in igb_up(), but function
igb_nfc_filter_exit() is exist in __igb_close(). In the process of speed
changing, only igb_nfc_filter_restore() is called, it will take a position
of ethertype bitmap.

Reproduce steps:
Step 1: Add a etype filter by ethtool
$ethtool -N eth0 flow-type ether proto 0x88F8 action 1
Step 2: Change the adapter speed to 100M/full duplex
$ethtool -s eth0 speed 100 duplex full
Step 3: Change the adapter speed to 1000M/full duplex
ethtool -s eth0 speed 1000 duplex full
Repeat step2 and step3, then dmesg the system log, you can find the error
message, add new ethtype filter is also failed.

This fixing is move igb_nfc_filter_exit() from __igb_close() to igb_down()
to make igb_nfc_filter_restore()/igb_nfc_filter_exit() is paired.
Signed-off-by: NGangfeng Huang <gangfeng.huang@ni.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Clean up a few sparse warnings, these following
functions can be made static:

drivers/net/ethernet/intel/igb/igb_main.c: warning: symbol
  'igb_add_mac_filter' was not declared. Should it be static?
drivers/net/ethernet/intel/igb/igb_main.c: warning: symbol
  'igb_del_mac_filter' was not declared. Should it be static?
drivers/net/ethernet/intel/igb/igb_main.c: warning: symbol
  'igb_set_vf_mac_filter' was not declared. Should it be static?
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Given that all callers of igb_update_stats() pass the same two arguments:
(adapter, &adapter->stats64), the second argument can be removed.
Signed-off-by: NBenjamin Poirier <bpoirier@suse.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The igb driver has logic to handle only one Tx timestamp at a time,
using a state bit lock to avoid multiple requests at once.

It may be possible, if incredibly unlikely, that a Tx timestamp event is
requested but never completes. Since we use an interrupt scheme to
determine when the Tx timestamp occurred we would never clear the state
bit in this case.

Add an igb_ptp_tx_hang() function similar to the already existing
igb_ptp_rx_hang() function. This function runs in the watchdog routine
and makes sure we eventually recover from this case instead of
permanently disabling Tx timestamps.

Note: there is no currently known way to cause this without hacking the
driver code to force it.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The igb driver can only handle one Tx timestamp request at a time.
This means it is possible for an application timestamp request to be
ignored.

There is no easy way for an administrator to determine if this occurred.
Add a new statistic which tracks this, tx_hwtstamp_skipped.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The igb driver uses a state bit lock to avoid handling more than one Tx
timestamp request at once. This is required because hardware is limited
to a single set of registers for Tx timestamps.

The state bit lock is not properly cleaned up during
igb_xmit_frame_ring() if the transmit fails such as due to DMA or TSO
failure. In some hardware this results in blocking timestamps until the
service task times out. In other hardware this results in a permanent
lock of the timestamp bit because we never receive an interrupt
indicating the timestamp occurred, since indeed the packet was never
transmitted.

Fix this by checking for DMA and TSO errors in igb_xmit_frame_ring() and
properly cleaning up after ourselves when these occur.
Reported-by: NReported-by: David Mirabito <davidm@metamako.com>
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Hardware related to the igb driver has a limitation of only handling one
Tx timestamp at a time. Thus, the driver uses a state bit lock to
enforce that only one timestamp request is honored at a time.

Unfortunately this suffers from a simple race condition. The bit lock is
not cleared until after skb_tstamp_tx() is called notifying the stack of
a new Tx timestamp. Even a well behaved application which sends only one
timestamp request at once and waits for a response might wake up and
send a new packet before the bit lock is cleared. This results in
needlessly dropping some Tx timestamp requests.

We can fix this by unlocking the state bit as soon as we read the
Timestamp register, as this is the first point at which it is safe to
unlock.

To avoid issues with the skb pointer, we'll use a copy of the pointer
and set the global variable in the driver structure to NULL first. This
ensures that the next timestamp request does not modify our local copy
of the skb pointer.

This ensures that well behaved applications do not accidentally race
with the unlock bit. Obviously an application which sends multiple Tx
timestamp requests at once will still only timestamp one packet at
a time. Unfortunately there is nothing we can do about this.
Reported-by: NDavid Mirabito <davidm@metamako.com>
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The new wake function is only used by the suspend/resume handlers that
are defined in inside of an #ifdef, which can cause this harmless
warning:

drivers/net/ethernet/intel/igb/igb_main.c:7988:13: warning: 'igb_deliver_wake_packet' defined but not used [-Wunused-function]

Removing the #ifdef, instead using a __maybe_unused annotation
simplifies the code and avoids the warning.

Fixes: b90fa876 ("igb: Enable reading of wake up packet")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The functions igb_read_phy_reg_gs40g/igb_write_phy_reg_gs40g (which were
removed in 2a3cdead) explicitly selected the required page at every phy_reg
access. Currently, igb_get_phy_id_82575 relays on the fact that page 0 is
already selected. The assumption is not fulfilled for my Lex 3I380CW
motherboard with integrated dual i211 based gigabit ethernet. This leads to igb
initialization failure and network interfaces are not working:

    igb: Intel(R) Gigabit Ethernet Network Driver - version 5.4.0-k
    igb: Copyright (c) 2007-2014 Intel Corporation.
    igb: probe of 0000:01:00.0 failed with error -2
    igb: probe of 0000:02:00.0 failed with error -2

In order to fix it, we explicitly select page 0 before first access to phy
registers.

See also: https://bugzilla.suse.com/show_bug.cgi?id=1009911
See also: http://www.lex.com.tw/products/pdf/3I380A&3I380CW.pdf

Fixes: 2a3cdead ("igb: Remove GS40G specific defines/functions")
Cc: <stable@vger.kernel.org> # 4.5+
Signed-off-by: NMatwey V Kornilov <matwey@sai.msu.ru>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Include HWTSTAMP_FILTER_NTP_ALL in net_hwtstamp_validate() as a valid
filter and update drivers which can timestamp all packets, or which
explicitly list unsupported filters instead of using a default case, to
handle the filter.

CC: Richard Cochran <richardcochran@gmail.com>
CC: Willem de Bruijn <willemb@google.com>
Signed-off-by: NMiroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This typo is quite common.  Fix it and add it to the spelling file so
that checkpatch catches it earlier.

Link: http://lkml.kernel.org/r/20170317011131.6881-2-sboyd@codeaurora.orgSigned-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, in igb_resume(), igb driver ignores the Wake Up Status (WUS)
and Wake Up Packet Memory (WUPM) registers. This patch enables the igb
driver to read the WUPM if the controller was woken by a wake up packet
that is not more than 128 bytes long (maximum WUPM size), then pass it
up the kernel network stack.
Signed-off-by: NKim Tatt Chuah <kim.tatt.chuah@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add functionality for the VF to request up to 3 additional MAC filters.
This is done using existing E1000_VF_SET_MAC_ADDR message, but with
additional message info - E1000_VF_MAC_FILTER_CLR to clear all unicast
MAC filters previously set for this VF and E1000_VF_MAC_FILTER_ADD to
add MAC filter.

Additional filters can be added only in case if administrator did not
set VF MAC explicitly and allowed to change default MAC to the VF.

Due to the limited number of RAR entries reserve at least 3 MAC filters
for the PF.

If SRIOV is supported by the NIC after this change RAR entries starting
from 1 to (RAR MAX ENTRIES - NUM SRIOV VFS) will be used for PF and VF
MAC filters.
Signed-off-by: NYury Kylulin <yury.kylulin@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Using the work which was done for ixgbe driver by Jacob Keller
commit 5d7daa35 ("ixgbe: improve mac filter handling") and Alexander
Duyck commit 0f079d22 ("ixgbe: Use __dev_uc_sync and __dev_uc_unsync
for unicast addresses") and out-of-tree igb driver add functionality to
manage (add and delete) MAC filters.
Signed-off-by: NYury Kylulin <yury.kylulin@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The ethtool API {get|set}_settings is deprecated.
We move this driver to new API {get|set}_link_ksettings.

As I don't have the hardware, I'd be very pleased if
someone may test this patch.
Signed-off-by: NPhilippe Reynes <tremyfr@gmail.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

There was a typo that I had left in the code comments for the igb and ixgbe
functions that enabled build_skb support.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This reverts commit f9d40f6a ("igb: Revert support for build_skb in
igb") and adds a few changes to update it to work with the latest version
of igb. We are now able to revert the removal of this due to the fact
that with the recent changes to the page count and the use of
DMA_ATTR_SKIP_CPU_SYNC we can make the pages writable so we should not be
invalidating the additional data added when we call build_skb.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

At this point we have 2 to 3 paths that can be taken depending on what Rx
modes are enabled.  In order to better support that and improve the
maintainability I am breaking out the common bits from those paths and
making them into their own functions.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

With the size of the frame limited we can now write to an offset within the
buffer instead of having to write at the very start of the buffer.  The
advantage to this is that it allows us to leave padding room for things
like supporting XDP in the future.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for using 3K buffers in order 1 pages the same way
we were using 2K buffers in 4K pages.  We are reserving 1K of room for now
to have space available for future headroom and tailroom when we enable
build_skb support.

One side effect of this patch is that we can end up using a larger buffer
if jumbo frames is enabled.  The impact shouldn't be too great, but it
could hurt small packet performance for UDP workloads if jumbo frames is
enabled as the truesize of frames will be larger.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Since there are potential drawbacks to the new Rx allocation approach I
thought it best to add a "chicken bit" so that we can turn the feature off
if in the event that a problem is found.

It also provides a means of validating the legacy Rx path in the event that
we are forced to fall back.  At some point in the future when we are
convinced we don't need it anymore we might be able to drop the legacy-rx
flag.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Update the handling of page addresses so that we always refer to them using
a void pointer, and try to use the consistent name of va indicating we are
working with a virtual address.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

We only need to sync the size of the frame that is read to test.  We don't
need to sync the entire Rx buffer.  This way the testing is more consistent
with how we handle things in the receive path.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In order to support the use of build_skb going forward it will be necessary
to place a maximum limit on the amount of data we can receive when jumbo
frames is not enabled.  In order to do this I am adding a new upper limit
for receive based on the size of a 2K buffer minus padding.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In the case of the Tx rings we need to only clear the Tx buffer_info when
we are resetting the rings.  Ideally we do this when we configure the ring
to bring it back up instead of when we are taking it down in order to avoid
dirtying pages we don't need to.

In addition we don't need to clear the Tx descriptor ring since we will
fully repopulate it when we begin transmitting frames and next_to_watch can
be cleared to prevent the ring from being cleaned beyond that point instead
of needing to touch anything in the Tx descriptor ring.

Finally with these changes we can avoid having to reset the skb member of
the Tx buffer_info structure in the cleanup path since the skb will always
be associated with the first buffer which has next_to_watch set.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This change makes it so that instead of going through the entire ring on Rx
cleanup we only go through the region that was designated to be cleaned up
and stop when we reach the region where new allocations should start.

In addition we can avoid having to perform a memset on the Rx buffer_info
structures until we are about to start using the ring again.  By deferring
this we can avoid dirtying the cache any more than we have to which can
help to improve the time needed to bring the interface down and then back
up again in a reset or suspend/resume cycle.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This change makes it so that we use the length of the packet instead of the
DD status bit to determine if a new descriptor is ready to be processed.
The obvious advantage is that it cuts down on reads as we don't really even
need the DD bit if going from a 0 to a non-zero value on size is enough to
inform us that the packet has been completed.

In addition I have updated the code so that we only reset the Rx descriptor
length for descriptor zero when resetting a ring instead of having to do a
memset with 0 over the entire ring.  By doing this we can save some time on
initialization.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>