This patch resolves an issue where the driver will display incorrect info
for Q/SFP+ modules that were inserted after the driver has been loaded.

This patch adds a call to identify_phy() in ixgbe_get_settings() prior to
calling get_link_capabilities() which needs the PHY data in order to
determine the correct settings.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

QSFP+ modules do not support auto negotiation and should advertise only
one speed at a time.

This patch adds logic in ethtool to allow setting and reporting the
advertised speed at either 1Gbps or 10Gbps, but not both. Also limits
the speed set in ixgbe_sfp_link_config_subtask() to highest supported.
Previously the link was set to whatever the supported speeds were.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch disables DCB prior to running the loopback test.
When DCB is enabled the frames may be modified on Tx (by adding vlan tag)
which will fail the check on Rx.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Tested-by: NJack Morgan <jack.morgan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds GB speed support for QSFP+ modules.
Autonegotiation is not supported with QSFP+. The user will have to set
the desired speed on both link partners using ethtool advertise setting.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes the read loop for the I2C data to account for the offset.

Also includes a whitespace cleanup and removes ret_val as it is not needed.

CC: Ben Hutchings <bhutchings@solarflare.com>
Reported-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Reviewed-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch is a partial reverse of:
commit dfcc4615
Author: Jacob Keller <jacob.e.keller@intel.com>
Date: Thu Nov 8 07:07:08 2012 +0000

  ixgbe: ethtool ixgbe_diag_test cleanup

Specifically forcing the laser before the link check can lead to
inconsistent results because it does not guarantee that the link will be
negotiated correctly. Such is the case when dual speed SFP+ module is
connected to a gigabit link partner.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

We were transversing the tx_ring with IXGBE_NUM_RX_QUEUES.  Now this define
happens to have the correct value but this is misleading and a change later
could easily make this no longer true.  I updated it to netdev->num_tx_queues
like we use in ixgbe_get_strings().
Signed-off-by: NDon Skidmore <donald.c.skidmore@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch renames the stats introduced by the busy poll feature so that they
are more inline with the current statistics naming schemes.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes several issues with the previous implementation of the
SFF data dump of SFP+ modules:

- removed the __IXGBE_READ_I2C flag - I2C access locking is handled in the
  HW specific routines

- fixed the read loop to read data from ee->offset to ee->len

- the reads fail if __IXGBE_IN_SFP_INIT is set in the process - this is
  needed because on some HW I2C operations can take long time and disrupt
  the SFP and link detection process
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Reported-by: NBen Hutchings <bhutchings@solarflare.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Originally ixgbe_device_supports_autoneg_fc() was only expected to
be called by copper devices.  This would lead to false information
to be displayed via ethtool.

v2: changed ixgbe_device_supports_autoneg_fc() to a bool function,
    it returns bool.  Based on feedback from David Miller
Signed-off-by: NDon Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add additional statistics to the ixgbe driver for ndo_ll_poll
Defined under LL_EXTENDED_STATS
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: NEliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds the mac type to the version in ethtool_regs.

This will make it easier to check the mac type when dumping registers with
ethtool. The drawback of this is that older versions of ethtool will only
be able to dump in hex format for 82599 and above  when used with the updated
driver.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch cleans up the logic in ixgbe_setup_loopback_test() to only access
registers applicable to the MAC type. AUTOC is only valid on MACs older than
X540. MACC is used for X540.

In addition it removes a read of AUTOC and uses the stored value to force the
link up.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds LX support to 82599 devices. This is an alternate patch to
the one suggested by Stefan Behte <s.behte@babiel.com>

In addition this patch includes some cleanups such as:
- removed parenthesis around "x == y ||" lines inside an if statement for
consistency.
- grouped the sx/lx sfp types along with srlr in ixgbe_get_settings() since
they all have the same supported, advertised and port values.
Signed-off-by: NDon Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Reported-by: NStefan Behte <s.behte@babiel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch makes sure that TXDCTL.WTHRESH is set to 1 when BQL is enabled
and EITR is set to more than 100k interrupts per second to avoid Tx timeouts.
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for reading data from SFP+ modules over i2c.
Signed-off-by: NAurélien Guillaume <footplus@gmail.com>
Signed-off-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This change adds support for the ethtool set_channels operation.

Since the ixgbe driver has to support DCB as well as the other modes the
assumption I made here is that the number of channels in DCB modes refers
to the number of queues per traffic class, not the number of queues total.

CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for the ethtool get_channels operation.

Since the ixgbe driver has to support DCB as well as the other modes the
assumption I made here is that the number of channels in DCB modes refers
to the number of queues per traffic class, not the number of queues total.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Reviewed-by: NJohn Fastabend <john.r.fastabend@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Signed-off-by: NDon Skidmore <donald.c.skidmore@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch removes the rval variable returns from function and replaces
them with direct returns in ixgbe_dcbnl_getnumtcs. It also changes how
ixgbe_gstrings_test is copied into data with memcpy in ixgbe_get_strings
because "*ixgbe_gstrings_test too small (32 vs 160)".
Signed-off-by: NJosh Hay <joshua.a.hay@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds a default case which goes to the next loop iteration
in the case where p is not set, preventing p from being dereferenced.
Signed-off-by: NJosh Hay <joshua.a.hay@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Removes the autoneg parameter from the setup_link functions.
Adds local variable autoneg to setup_link functions to be passed
to get_link_capabilities functions if needed.
Signed-off-by: NJosh Hay <joshua.a.hay@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>

This patch updates the filters for ethtool's get_ts_info to return support for
all filters which can be supported by upscaling to ptp_v2_event. The intent
behind this change is due to reasoning that we do in fact support the
filters. (hwtstamp_ioctl returns success after setting the filter to the
upscaled version). In this way we can remain consistent over which filters are
supported via the get_ts_info ioctl and which filters are in practice actually
supported.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch cleans up the ethtool diagnostics test by ensuring that the tests
work properly regardless of what state the adapter was in. The SRIOV VF check is
done at the beginning, forgoing the link test. The if_running -> dev_close is
moved before the link test, as well as a call to enable the Tx laser. This
ensures that the link test will return valid results even when adapter was
previously down. Also, a call to disable the Tx laser is added if the device
was down before the start. This ensures consistent behavior of the Tx laser
before and after the diagnostic checks. The end result is consistent behavior
regardless of device state.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch enables ethtool to correctly identify flow control (pause
frame) auto negotiation, as well as disallow enabling it when it is not
supported. The ixgbe_device_supports_autoneg_fc function is exported and
used for this purpose.

There is also one minor cleanup of the device_supports_autoneg_fc by
removing an unnecessary return statement.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Where a PTP clock driver is associated with a net or PHY driver, it
should be enabled automatically whenever that driver is enabled.
Therefore:

- Make PTP clock drivers select rather than depending on PTP_1588_CLOCK
- Remove separate boolean options for PTP clock drivers that are built
  as part of net driver modules.  (This also fixes cases where the PTP
  subsystem is wrongly forced to be built-in.)
- Set 'default y' for PTP clock drivers that depend on specific net
  drivers but are built separately
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch corrects the ethtool get_ts_info functon which did not state that
software timestamping was supported, even though it is.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
CC: Stable <stable@vger.kernel.org> [3.5]
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We were not correctly freeing the temporary rings on error in
ixgbe_set_ring_param.  In order to correct this I am unwinding a number of
changes that were made in order to get things back to the original working
form with modification for the current ring layouts.

This approach has multiple advantages including a smaller memory footprint,
and the fact that the interface is stopped while we are allocating the rings
meaning that there is less potential for some sort of memory corruption on the
ring.

The only disadvantage I see with this approach is that on a Rx allocation
failure we will report an error and only update the Tx rings.  However the
adapter should be fully functional in this state and the likelihood of such
an error is very low.  In addition it is not unreasonable to expect the
user to need to recheck the ring configuration should they experience an
error setting the ring sizes.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch fixes a development issue that occurred due to invalid modes reported
in the ethtool get_ts_info function. The issue is resolved by removing
unsupported modes from the Rx supported list.

CC: stable <stable@vger.kernel.org> [3.5]
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

All of our hardware supports RSS even if it is only for a single queue.  So
instead of toting around the RSS enable flag I am updating the code so that
all devices are enabled and if we want to disable RSS it is indicated via
the RSS mask.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

It makes much more sense for us to count q_vectors instead of MSI-X
vectors.  We were using num_msix_vectors to find the number of q_vectors in
multiple places.  This was wasteful since we only had one place that
actually needs the number of MSI-X vectors and that is in slow path.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch cleans up the method used for determining the link speed of
devices. The old method re-wrote some logic already existing in a mac.ops
function which should be used instead. The result is much simpler to
understand and removes a strange double-check of logic, as well as reducing
code redundancy.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for the ethtool get_ts_info operation, which enables
access of available timestamp/timesync support for that device. It can query
which ptp clock device is associated with the particular port.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This change cleans up the logic in the priority based flow control
configuration routines.  Both the 82599 and 82598 based routines perform
similar functions however they are both arranged completely differently.
This patch goes over both of them to clean up the code.

In addition I am dropping the ixgbe_fc_pfc flow control mode and instead
just replacing it with checks for if priority flow control is enabled.
This allows us to maintain some of the link flow control information which
allows for an easier transition between link and priority flow control.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

igb and ixgbe incorrectly call netdev_tx_reset_queue() from
i{gb|xgbe}_clean_tx_ring() this sort of works in most cases except
when the number of real tx queues changes. When the number of real
tx queues changes netdev_tx_reset_queue() only gets called on the
new number of queues so when we reduce the number of queues we risk
triggering the watchdog timer and repeated device resets.

So this is not only a cosmetic issue but causes real bugs. For
example enabling/disabling DCB or FCoE in ixgbe will trigger this.

CC: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Tested-by: NJohn Bishop <johnx.bishop@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch consolidates the case logic for checking whether a device supports
WoL into a single place. Previously ethtool and probe used similar logic that
was copied and maintained separately. This patch encapsulates the core logic
into a function so that a user only has to update one place.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch replaces the variable name data with the variable name features
for ixgbe_fix_features and ixgbe_set_features.  This helps to make some
issues more obvious such as the fact that we were disabling Rx VLAN tag
stripping when we should have been forcing it to be enabled when DCB is
enabled.

In addition there was deprecated code present that was disabling the LRO
flag if we had the itr value set too low.  I have updated this logic so
that we will now allow the LRO flag to be set, but will not enable RSC
until the rx-usecs value is high enough to allow enough time for Rx packet
coalescing.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch adds support for enabling or disabling UDP RSS via the
ethtool -N rx-flow-hash command.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

This patch replaces the existing Rx hot-path in the ixgbe driver with a new
implementation that is based on performing a double buffered receive.  The
ixgbe driver already had something similar in place for its' packet split
path, however in that case we were still receiving the header for the
packet into the sk_buff.  The big change here is the entire receive path
will receive into pages only, and then pull the header out of the page and
copy it into the sk_buff data.  There are several motivations behind this
approach.

First, this allows us to avoid several cache misses as we were taking a
set of cache misses for allocating the sk_buff and then another set for
receiving data into the sk_buff.  We are able to avoid these misses on
receive now as we allocate the sk_buff when data is available.

Second we are able to see a considerable performance gain when an IOMMU is
enabled because we are no longer unmapping every buffer on receive.
Instead we can delay the unmap until we are unable to use the page, and
instead we can simply call sync_single_range on the half of the page that
contains new data.

Finally we are able to drop a considerable amount of code from the driver
as we no longer have to support 2 different receive modes, packet split and
one buffer.  This allows us to optimize the Rx path further since less
branching is required.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Tested-by: NStephen Ko <stephen.s.ko@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>