Currently, when debugging AF_XDP workloads, one can correlate the -ENXIO
return code as the case that XSK is not in the bound state. Returning
same code from ndo_xsk_wakeup can be misleading and simply makes it
harder to follow what is going on.

Change ENXIOs in i40e's ndo_xsk_wakeup() implementation to EINVALs, so
that when probing it is clear that something is wrong on the driver
side, not the xsk_{recv,send}msg.

There is a -ENETDOWN that can happen from both kernel/driver sides
though, but I don't have a correct replacement for this on one of the
sides, so let's keep it that way.
Signed-off-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220413153015.453864-10-maciej.fijalkowski@intel.com

When XSK pool uses need_wakeup feature, correlate -ENOBUFS that was
returned from xdp_do_redirect() with a XSK Rx queue being full. In such
case, terminate the Rx processing that is being done on the current HW
Rx ring and let the user space consume descriptors from XSK Rx queue so
that there is room that driver can use later on.

Introduce new internal return code I40E_XDP_EXIT that will indicate case
described above.

Note that it does not affect Tx processing that is bound to the same
NAPI context, nor the other Rx rings.
Signed-off-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220413153015.453864-7-maciej.fijalkowski@intel.com

The 'if (ntu == rx_ring->count)' block in i40e_alloc_rx_buffers_zc()
was previously residing in the loop, but after introducing the
batched interface it is used only to wrap-around the NTU descriptor,
thus no more need to assign 'xdp'.

'cleaned_count' in i40e_clean_rx_irq_zc() was previously being
incremented in the loop, but after commit f12738b6
("i40e: remove unnecessary cleaned_count updates") it gets
assigned only once after it, so the initialization can be dropped.

Fixes: 6aab0bb0 ("i40e: Use the xsk batched rx allocation interface")
Fixes: f12738b6 ("i40e: remove unnecessary cleaned_count updates")
Signed-off-by: NAlexander Lobakin <alexandr.lobakin@intel.com>
Acked-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: NGeorge Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For now, if the XDP prog returns XDP_PASS on XSK, the metadata will
be lost as it doesn't get copied to the skb.

Copy it along with the frame headers. Account its size on skb
allocation, and when copying just treat it as a part of the frame
and do a pull after to "move" it to the "reserved" zone.

net_prefetch() xdp->data_meta and align the copy size to speed-up
memcpy() a little and better match i40e_construct_skb().

Fixes: 0a714186 ("i40e: add AF_XDP zero-copy Rx support")
Suggested-by: NJesper Dangaard Brouer <brouer@redhat.com>
Suggested-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: NAlexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: NMichal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

{__,}napi_alloc_skb() allocates and reserves additional NET_SKB_PAD
+ NET_IP_ALIGN for any skb.
OTOH, i40e_construct_skb_zc() currently allocates and reserves
additional `xdp->data - xdp->data_hard_start`, which is
XDP_PACKET_HEADROOM for XSK frames.
There's no need for that at all as the frame is post-XDP and will
go only to the networking stack core.
Pass the size of the actual data only to __napi_alloc_skb() and
don't reserve anything. This will give enough headroom for stack
processing.

Fixes: 0a714186 ("i40e: add AF_XDP zero-copy Rx support")
Signed-off-by: NAlexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: NMichal Swiatkowski <michal.swiatkowski@linux.intel.com>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Move desc_array from the driver to the pool. The reason behind this is
that we can then reuse this array as a temporary storage for descriptors
in all zero-copy drivers that use the batched interface. This will make
it easier to add batching to more drivers.

i40e is the only driver that has a batched Tx zero-copy
implementation, so no need to touch any other driver.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NAlexander Lobakin <alexandr.lobakin@intel.com>
Link: https://lore.kernel.org/bpf/20220125160446.78976-6-maciej.fijalkowski@intel.com

In non trivial scenarios, the action id alone is not sufficient to
identify the program causing the warning. Before the previous patch,
the generated stack-trace pointed out at least the involved device
driver.

Let's additionally include the program name and id, and the relevant
device name.

If the user needs additional infos, he can fetch them via a kernel
probe, leveraging the arguments added here.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NToke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/ddb96bb975cbfddb1546cf5da60e77d5100b533c.1638189075.git.pabeni@redhat.com

Fix the following coccicheck warning:
./drivers/net/ethernet/intel/i40e/i40e_xsk.c:229:35-40: WARNING:
conversion to bool not needed here
./drivers/net/ethernet/intel/ice/ice_xsk.c:399:35-40: WARNING:
conversion to bool not needed here
Reported-by: NAbaci Robot <abaci@linux.alibaba.com>
Signed-off-by: NYang Li <yang.lee@linux.alibaba.com>
Tested-by: NTony Brelinski <tony.brelinski@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Use the new xsk batched rx allocation interface for the zero-copy data
path. As the array of struct xdp_buff pointers kept by the driver is
really a ring that wraps, the allocation routine is modified to detect
a wrap and in that case call the allocation function twice. The
allocation function cannot deal with wrapped rings, only arrays. As we
now know exactly how many buffers we get and that there is no
wrapping, the allocation function can be simplified even more as all
if-statements in the allocation loop can be removed, improving
performance.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210922075613.12186-6-magnus.karlsson@gmail.com

The Intel drivers all have rcu_read_lock()/rcu_read_unlock() pairs around
XDP program invocations. However, the actual lifetime of the objects
referred by the XDP program invocation is longer, all the way through to
the call to xdp_do_flush(), making the scope of the rcu_read_lock() too
small. This turns out to be harmless because it all happens in a single
NAPI poll cycle (and thus under local_bh_disable()), but it makes the
rcu_read_lock() misleading.

Rather than extend the scope of the rcu_read_lock(), just get rid of it
entirely. With the addition of RCU annotations to the XDP_REDIRECT map
types that take bh execution into account, lockdep even understands this to
be safe, so there's really no reason to keep it around.
Signed-off-by: NToke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> # i40e
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Cc: intel-wired-lan@lists.osuosl.org
Link: https://lore.kernel.org/bpf/20210624160609.292325-12-toke@redhat.com

Add missing exception tracing to XDP when a number of different errors
can occur. The support was only partial. Several errors where not
logged which would confuse the user quite a lot not knowing where and
why the packets disappeared.

Fixes: 74608d17 ("i40e: add support for XDP_TX action")
Fixes: 0a714186 ("i40e: add AF_XDP zero-copy Rx support")
Reported-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Fix so that single packets are received immediately instead of in
batches of 8. If you sent 1 pps to a system, you received 8 packets
every 8 seconds instead of 1 packet every second. The problem behind
this was that the work_done reporting from the Tx part of the driver
was broken. The work_done reporting in i40e controls not only the
reporting back to the napi logic but also the setting of the interrupt
throttling logic. When Tx or Rx reports that it has more to do,
interrupts are throttled or coalesced and when they both report that
they are done, interrupts are armed right away. If the wrong work_done
value is returned, the logic will start to throttle interrupts in a
situation where it should have just enabled them. This leads to the
undesired batching behavior seen in user-space.

Fix this by returning the correct boolean value from the Tx xsk
zero-copy path. Return true if there is nothing to do or if we got
fewer packets to process than we asked for. Return false if we got as
many packets as the budget since there might be more packets we can
process.

Fixes: 3106c580 ("i40e: Use batched xsk Tx interfaces to increase performance")
Reported-by: NSreedevi Joshi <sreedevi.joshi@intel.com>
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Acked-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

A bunch of header comments were showing warnings when compiling
with W=1. Fix them all at once. This changes only comments.
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Optimize i40e_run_xdp_zc() for the XDP program verdict being
XDP_REDIRECT in the xsk zero-copy path. This path is only used when
having AF_XDP zero-copy on and in that case most packets will be
directed to user space. This provides a little over 100k extra packets
in throughput on my server when running l2fwd in xdpsock.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Tested-by: NGeorge Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Fixes the following sparse warnings:
i40e_main.c:5953:32: warning: cast from restricted __le16
i40e_main.c:8008:29: warning: incorrect type in assignment (different base types)
i40e_main.c:8008:29:    expected unsigned int [assigned] [usertype] ipa
i40e_main.c:8008:29:    got restricted __le32 [usertype]
i40e_main.c:8008:29: warning: incorrect type in assignment (different base types)
i40e_main.c:8008:29:    expected unsigned int [assigned] [usertype] ipa
i40e_main.c:8008:29:    got restricted __le32 [usertype]
i40e_txrx.c:1950:59: warning: incorrect type in initializer (different base types)
i40e_txrx.c:1950:59:    expected unsigned short [usertype] vlan_tag
i40e_txrx.c:1950:59:    got restricted __le16 [usertype] l2tag1
i40e_txrx.c:1953:40: warning: cast to restricted __le16
i40e_xsk.c:448:38: warning: invalid assignment: |=
i40e_xsk.c:448:38:    left side has type restricted __le64
i40e_xsk.c:448:38:    right side has type int

Fixes: 2f4b411a ("i40e: Enable cloud filters via tc-flower")
Fixes: 2a508c64 ("i40e: fix VLAN.TCI == 0 RX HW offload")
Fixes: 3106c580 ("i40e: Use batched xsk Tx interfaces to increase performance")
Fixes: 8f88b303 ("i40e: Add infrastructure for queue channel support")
Signed-off-by: NNorbert Ciosek <norbertx.ciosek@intel.com>
Tested-by: NTony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Fold the count decrement into the while-statement.
Reviewed-by: NMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Consolidate the actions performed on the packet based on the XDP
program result into a separate function that is easier to read and
maintain. Simplify the i40e_construct_skb_zc function, so that the
input xdp buffer is always freed, regardless of whether the output
skb is successfully created or not. Simplify the behavior of the
i40e_clean_rx_irq_zc function, so that the current packet descriptor
is dropped when function i40_construct_skb_zc returns an error as
opposed to re-processing the same description on the next invocation.
Signed-off-by: NCristian Dumitrescu <cristian.dumitrescu@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

For performance reasons, remove the redundant buffer info updates
(*bi = NULL). The buffers ready to be cleaned can easily be tracked
based on the ring next-to-clean variable, which is consistently
updated.
Signed-off-by: NCristian Dumitrescu <cristian.dumitrescu@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

For performance reasons, remove the redundant updates of the cleaned_count
variable, as its value can be computed based on the ring next-to-clean
variable, which is consistently updated.
Signed-off-by: NCristian Dumitrescu <cristian.dumitrescu@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

For performance reasons, avoid writing the ring next-to-clean pointer
value back to memory on every update, as it is not really necessary.
Instead, simply read it at initialization into a local copy, update
the local copy as necessary and write the local copy back to memory
after the last update.
Signed-off-by: NCristian Dumitrescu <cristian.dumitrescu@intel.com>
Tested-by: NKiran Bhandare <kiranx.bhandare@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Currently, the function i40e_construct_skb_zc only frees the input xdp
buffer when the output skb is successfully built. On error, the
function i40e_clean_rx_irq_zc does not commit anything for the current
packet descriptor and simply exits the packet descriptor processing
loop, with the plan to restart the processing of this descriptor on
the next invocation. Therefore, on error the ring next-to-clean
pointer should not advance, the xdp i.e. *bi buffer should not be
freed and the current buffer info should not be invalidated by setting
*bi to NULL. Therefore, the *bi should only be set to NULL when the
function i40e_construct_skb_zc is successful, otherwise a NULL *bi
will be dereferenced when the work for the current descriptor is
eventually restarted.

Fixes: 3b4f0b66 ("i40e, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL")
Signed-off-by: NCristian Dumitrescu <cristian.dumitrescu@intel.com>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/r/20210111181138.49757-1-cristian.dumitrescu@intel.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

On the Rx side, the next_to_use index points to the next item in the
HW ring to be refilled/allocated, and next_to_clean points to the next
item to potentially be processed.

When the HW Rx ring is fully refilled, i.e. no packets has been
processed, the next_to_use will be next_to_clean - 1. When the ring is
fully processed next_to_clean will be equal to next_to_use. The latter
case is where a bug is triggered.

If the next_to_use bits are not cleared, and the "fully processed"
state is entered, a stale descriptor can be processed.

The skb-path correctly clear the status bit for the next_to_use
descriptor, but the AF_XDP zero-copy path did not do that.

This change adds the status bits clearing of the next_to_use
descriptor.

Fixes: 3b4f0b66 ("i40e, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL")
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Remove a redundant assignment of the software ring pointer in the i40e
driver. The variable is assigned twice with no use in between, so just
get rid of the first occurrence.

Fixes: 3b4f0b66 ("i40e, xsk: Migrate to new MEM_TYPE_XSK_BUFF_POOL")
Signed-off-by: NMarek Majtyka <marekx.majtyka@intel.com>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NGeorge Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Use the new batched xsk interfaces for the Tx path in the i40e driver
to improve performance. On my machine, this yields a throughput
increase of 4% for the l2fwd sample app in xdpsock. If we instead just
look at the Tx part, this patch set increases throughput with above
20% for Tx.

Note that I had to explicitly loop unroll the inner loop to get to
this performance level, by using a pragma. It is honored by both clang
and gcc and should be ignored by versions that do not support
it. Using the -funroll-loops compiler command line switch on the
source file resulted in a loop unrolling on a higher level that
lead to a performance decrease instead of an increase.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/1605525167-14450-6-git-send-email-magnus.karlsson@gmail.com

Remove the unnecessary access to the software ring for the AF_XDP
zero-copy driver. This was used to record the length of the packet so
that the driver Tx completion code could sum this up to produce the
total bytes sent. This is now performed during the transmission of the
packet, so no need to record this in the software ring.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/1605525167-14450-3-git-send-email-magnus.karlsson@gmail.com

The "failure" variable is used without being initialized.  It should be
set to false.

Fixes: 8cbf7414 ("i40e, xsk: move buffer allocation out of the Rx processing loop")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NGeorge Kuruvinakunnel <george.kuruvinakunnel@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Instead of checking in each iteration of the Rx packet processing
loop, move the allocation out of the loop and do it once for each napi
activation.

For AF_XDP the rx_drop benchmark was improved by 6%.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

The software prefetching of HW descriptors has a negative impact on
the performance. Therefore, it is now removed.

Performance for the rx_drop benchmark increased with 2%.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Test for dma_need_sync earlier to increase
performance. xsk_buff_dma_sync_for_cpu() takes an xdp_buff as
parameter and from that the xsk_buff_pool reference is dug out. Perf
shows that this dereference causes a lot of cache misses. But as the
buffer pool is now sent down to the driver at zero-copy initialization
time, we might as well use this pointer directly, instead of going via
the xsk_buff and we can do so already in xsk_buff_dma_sync_for_cpu()
instead of in xp_dma_sync_for_cpu. This gets rid of these cache
misses.

Throughput increases with 3% for the xdpsock l2fwd sample application
on my machine.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-11-git-send-email-magnus.karlsson@intel.com

Rename the AF_XDP zero-copy driver interface functions to better
reflect what they do after the replacement of umems with buffer
pools in the previous commit. Mostly it is about replacing the
umem name from the function names with xsk_buff and also have
them take the a buffer pool pointer instead of a umem. The
various ring functions have also been renamed in the process so
that they have the same naming convention as the internal
functions in xsk_queue.h. This so that it will be clearer what
they do and also for consistency.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-3-git-send-email-magnus.karlsson@intel.com

Replace the explicit umem reference passed to the driver in AF_XDP
zero-copy mode with the buffer pool instead. This in preparation for
extending the functionality of the zero-copy mode so that umems can be
shared between queues on the same netdev and also between netdevs. In
this commit, only an umem reference has been added to the buffer pool
struct. But later commits will add other entities to it. These are
going to be entities that are different between different queue ids
and netdevs even though the umem is shared between them.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-2-git-send-email-magnus.karlsson@intel.com

Move the check if the HW Tx ring is full to outside the send
loop. Currently it is checked for every single descriptor that we
send. Instead, tell the send loop to only process a maximum number of
packets equal to the number of available slots in the Tx ring. This
way, we can remove the check inside the send loop to and gain some
performance.
Suggested-by: NSridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Improve the performance of the AF_XDP zero-copy Tx completion
path. When there are no XDP buffers being sent using XDP_TX or
XDP_REDIRECT, we do not have go through the SW ring to clean up any
entries since the AF_XDP path does not use these. In these cases, just
fast forward the next-to-use counter and skip going through the SW
ring. The limit on the maximum number of entries to complete is also
removed since the algorithm is now O(1). To simplify the code path, the
maximum number of entries to complete for the XDP path is therefore
also increased from 256 to 512 (the default number of Tx HW
descriptors). This should be fine since the completion in the XDP path
is faster than in the SKB path that has 256 as the maximum number.

This patch provides around 4% throughput improvement for the l2fwd
application in xdpsock on my machine.
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Reviewed-by: NSridhar Samudrala <sridhar.samudrala@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

Convert all the remaining 'fall through" code comments to the newer
'fallthrough;' keyword.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: NAaron Brown <aaron.f.brown@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

The comment above i40e_run_xdp_zc() was clearly copy-pasted from
function i40e_xsk_umem_setup, which is just above.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Remove MEM_TYPE_ZERO_COPY in favor of the new MEM_TYPE_XSK_BUFF_POOL
APIs. The AF_XDP zero-copy rx_bi ring is now simply a struct xdp_buff
pointer.

v4->v5: Fixed "warning: Excess function parameter 'bi' description in
        'i40e_construct_skb_zc'". (Jakub)
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Cc: intel-wired-lan@lists.osuosl.org
Link: https://lore.kernel.org/bpf/20200520192103.355233-9-bjorn.topel@gmail.com

Continuing the path to support MEM_TYPE_XSK_BUFF_POOL, the AF_XDP
zero-copy/sk_buff rx_bi rings are now separate. Functions to properly
allocate the different rings are added as well.

v3->v4: Made i40e_fd_handle_status() static. (kbuild test robot)
v4->v5: Fix kdoc for i40e_clean_programming_status(). (Jakub)
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Cc: intel-wired-lan@lists.osuosl.org
Link: https://lore.kernel.org/bpf/20200520192103.355233-8-bjorn.topel@gmail.com

As a first step to migrate i40e to the new MEM_TYPE_XSK_BUFF_POOL
APIs, code that accesses the rx_bi (SW/shadow ring) is refactored to
use an accessor function.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Cc: intel-wired-lan@lists.osuosl.org
Link: https://lore.kernel.org/bpf/20200520192103.355233-7-bjorn.topel@gmail.com

Move the AF_XDP zero-copy driver interface to its own include file
called xdp_sock_drv.h. This, hopefully, will make it more clear for
NIC driver implementors to know what functions to use for zero-copy
support.

v4->v5: Fix -Wmissing-prototypes by include header file. (Jakub)
Signed-off-by: NMagnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-4-bjorn.topel@gmail.com

Intel drivers implement native AF_XDP zerocopy in separate C-files,
that have its own invocation of bpf_prog_run_xdp(). The setup of
xdp_buff is also handled in separately from normal code path.

This patch update XDP frame_sz for AF_XDP zerocopy drivers i40e, ice
and ixgbe, as the code changes needed are very similar.  Introduce a
helper function xsk_umem_xdp_frame_sz() for calculating frame size.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NBjörn Töpel <bjorn.topel@intel.com>
Cc: intel-wired-lan@lists.osuosl.org
Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/158945347511.97035.8536753731329475655.stgit@firesoul