i40e: Remove circular header dependencies and fix headers

Similarly as for ice driver [1] there are also circular header
dependencies in i40e driver:
i40e.h -> i40e_virtchnl_pf.h -> i40e.h

Another issue is that i40e header files does not contain their own
dependencies on other header files (both private and standard) so their
inclusion in .c file require to add these deps in certain order to
that .c file to make it compilable.

Fix both issues by removal the mentioned circular dependency, by filling
i40e headers with their dependencies so they can be placed anywhere in
a source code. Additionally remove bunch of includes from i40e.h super
header file that are not necessary and include i40e.h only in .c files
that really require it.

[1] 649c87c6ff52 ("ice: remove circular header dependencies on ice.h")

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

i40e, xsk: Terminate Rx side of NAPI when XSK Rx queue gets full

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: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220413153015.453864-7-maciej.fijalkowski@intel.com

intel-ethernet: clean up W=1 warnings in kdoc

This takes care of all of the trivial W=1 fixes in the Intel
Ethernet drivers, which allows developers and maintainers to
build more of the networking tree with more complete warning
checks.

There are three classes of kdoc warnings fixed:
- cannot understand function prototype: 'x'
- Excess function parameter 'x' description in 'y'
- Function parameter or member 'x' not described in 'y'

All of the changes were trivial comment updates on
function headers.

Inspired by Lee Jones' series of wireless work to do the same.
Compile tested only, and passes simple test of
$ git ls-files *.[ch] | egrep drivers/net/ethernet/intel | \
xargs scripts/kernel-doc -none

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

i40e, xsk: remove HW descriptor prefetch in AF_XDP path

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: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

i40e: Separate kernel allocated rx_bi rings from AF_XDP rings

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: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: intel-wired-lan@lists.osuosl.org
Link: https://lore.kernel.org/bpf/20200520192103.355233-8-bjorn.topel@gmail.com

i40e: DRY rx_ptype handling code

Move rx_ptype extracting to i40e_process_skb_fields() to avoid
duplicating the code.

Signed-off-by: Michał Mirosław <michal.miroslaw@atendesoftware.pl>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e: fix VLAN.TCI == 0 RX HW offload

This fixes two bugs in hardware VLAN offload:
1. VLAN.TCI == 0 was being dropped
2. there was a race between disabling of VLAN RX feature in hardware
and processing RX queue, where packets processed in this window
could have their VLAN information dropped

Fix moves the VLAN handling into i40e_process_skb_fields() to save on
duplicated code. i40e_receive_skb() becomes trivial and so is removed.

Signed-off-by: Michał Mirosław <michal.miroslaw@atendesoftware.pl>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e: disallow changing the number of descriptors when AF_XDP is on

When an AF_XDP UMEM is attached to any of the Rx rings, we disallow a
user to change the number of descriptors via e.g. "ethtool -G IFNAME".

Otherwise, the size of the stash/reuse queue can grow unbounded, which
would result in OOM or leaking userspace buffers.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e: clean zero-copy XDP Rx ring on shutdown/reset

Outstanding Rx descriptors are temporarily stored on a stash/reuse
queue. When/if the HW rings comes up again, entries from the stash are
used to re-populate the ring.

The latter required some restructuring of the allocation scheme for
the AF_XDP zero-copy implementation. There is now a fast, and a slow
allocation. The "fast allocation" is used from the fast-path and
obtains free buffers from the fill ring and the internal recycle
mechanism. The "slow allocation" is only used in ring setup, and
obtains buffers from the fill ring and the stash (if any).

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e: clean zero-copy XDP Tx ring on shutdown/reset

When the zero-copy enabled XDP Tx ring is torn down, due to
configuration changes, outstanding frames on the hardware descriptor
ring are queued on the completion ring.

The completion ring has a back-pressure mechanism that will guarantee
that there is sufficient space on the ring.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

i40e: move common Tx functions to i40e_txrx_common.h

This patch prepares for the upcoming zero-copy Tx functionality, by
moving common functions and refactor chunks of code into re-usable
functions, used both by the regular path and zero-copy path.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

i40e: move common Rx functions to i40e_txrx_common.h

This patch prepares for the upcoming zero-copy Rx functionality, by
moving/changing linkage of common functions, used both by the regular
path and zero-copy path.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>