There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use "flexible array members" for these cases. The older
style of one-element or zero-length arrays should no longer be used.
Reference:
https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arraysReported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

Since the starting value in the for loop is greater than or equal to 1,
the restriction is CAS_FLAG_REG_PLUS is in the file cassini.h is
defined as 0x1 by macro, and the for loop and if condition is not
satisfied, so the code here is redundant.

Clean up the following smatch warning:

drivers/net/ethernet/sun/cassini.c:3513 cas_start_dma() warn: we never
enter this loop.

drivers/net/ethernet/sun/cassini.c:1239 cas_init_rx_dma() warn: we never
enter this loop.

drivers/net/ethernet/sun/cassini.c:1247 cas_init_rx_dma() warn: we never
enter this loop.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Simon Horman says:

====================
Add AF_XDP zero-copy support for NFP

Niklas Söderlund says:

This series adds AF_XDP zero-copy support for the NFP driver. The series
is based on previous work done by Jakub Kicinski.

Patch 1/5 and 2/5 prepares the driver for AF_XDP support by refactoring
functions that will act differently once AF_XDP is active or not making
the driver easier to read and by preparing some functions to be reused
outside the local file scope. Patch 3/5 and 4/5 prepares the driver for
dealing the UMEM while finally patch 5/5 adds AF_XDP support.

Based on work by Jakub Kicinski.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds zero-copy Rx and Tx support for AF_XDP sockets. It do so
by adding a separate NAPI poll function that is attached to a each
channel when the XSK socket is attached with XDP_SETUP_XSK_POOL, and
restored when the XSK socket is terminated, this is done per channel.

Support for XDP_TX is implemented and the XDP buffer can safely be moved
from the Rx to the Tx queue and correctly freed and returned to the XSK
pool once it's transmitted.

Note that when AF_XDP zero-copy is enabled, the XDP action XDP_PASS
will allocate a new buffer and copy the zero-copy frame prior
passing it to the kernel stack.

This patch is based on previous work by Jakub Kicinski.
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In preparation for adding AF_XDP support add a configuration check to
make sure the buffer size can not be set to a larger value then the XSK
socket chunk size.
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Each data path needs an array of xsk pools to track if an xsk socket is
in use. Add this array and make sure it's handled correctly when the
data path is duplicated.
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There will be more NAPI register logic once AF_XDP support is
added, wrap our already conditional napi add/del into helpers.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are some common functionality that can be reused in the upcoming
AF_XDP support. Expose those functions in the header. While at it mark
some arguments of nfp_net_rx_csum() as const.
Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Horatiu Vultur says:

====================
net: sparx5: Add PTP Hardware Clock support

Add support for PTP Hardware Clock (PHC) for sparx5.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Implement the function get_ts_info in ethtool_ops which is needed to get
the HW capabilities for timestamping.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When doing 2-step timestamping the HW will generate an interrupt when it
managed to timestamp a frame. It is the SW responsibility to read it
from the FIFO.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Update both the extraction and injection to do timestamping of the
frames. The extraction is always doing the timestamping while for
injection is doing the timestamping only if it is configured.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implement the ioctl callbacks SIOCSHWTSTAMP and SIOCGHWTSTAMP to allow
to configure the ports to enable/disable timestamping for TX. The RX
timestamping is always enabled. The HW is capable to run both 1-step
timestamping and 2-step timestamping.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The sparx5 has 3 PHC. Enable each of them, for now all the
timestamping is happening on the first PHC.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add the registers that will be used to configure the PHC in the HW.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for ptp interrupt. This interrupt is used when using 2-step
timestamping. For each timestamp that is added in a queue, an interrupt
is generated.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend dt-bindings for sparx5 with ptp interrupt. This is generated
when doing 2-step timestamping and the timestamp can be read from the
FIFO.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently the ifh is not changed, it is fixed for each frame for each
port that is sent out. Move this on the stack because this ifh needs to
be change based on the frames that are send out. This is needed for PTP
frames.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Arun Ramadoss says:

====================
Add support for LAN937x T1 Phy Driver

LAN937x is a Multi-port 100Base-T1 Switch and it internally uses LAN87xx
T1 Phy.  This series of patch update the initialization routine for the
LAN87xx phy and also add LAN937x part support. Added the T1 Phy
master-slave configuration through ethtool.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

To configure the T1 phy as master or slave using the ethtool -s <dev>
master-slave <forced-master/forced-slave>, the config_aneg and read
status functions are added.
Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@microchip.com>
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

LAN937x T1 switch is based on LAN87xx Phy, so reusing the init script of
the LAN87xx. There is a workaround in accessing the DSP bank register
for LAN937x Phy. Whenever there is a bank switch to DSP registers, then
we need a one dummy read access before proceeding to the actual register
access.
Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@microchip.com>
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The new initialization sequence is the improvement to the existing init
routine. Init routine does soft reset, run init script and set
Hw_init. Added the new access_smi_poll_timeout() for polling smi
bank write.
Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@microchip.com>
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Removed the empty lines in struct phy_drivers.
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Used the PHY_ID_MATCH_MODEL MACRO for describing the phy_id and
phy_id_mask.
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replaced the current code of resetting of LAN87xx phy to
genphy_soft_reset library function.
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Divya Koppera says:

====================
Add support for 1588 in LAN8814

The following patch series contains:
- Fix for concurrent register access, which provides
  atomic access to extended page register reads/writes.
- Provides dt-bindings related to latency and timestamping
  that are required for LAN8814 phy.
- 1588 hardware timestamping support in LAN8814 phy.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add support for 1588 in LAN8814 phy driver.
It supports 1-step and 2-step timestamping.
Co-developed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Divya Koppera <Divya.Koppera@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Supports configuring latency values and also adds
check for phy timestamping feature.

Signed-off-by: Divya Koppera<Divya.Koppera@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Make Extended page register accessing atomic,
to overcome unexpected output from register
reads/writes.

Fixes: 7c2dcfa2 ("net: phy: micrel: Add support for LAN8804 PHY")
Signed-off-by: Divya Koppera<Divya.Koppera@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Menglong Dong says:

====================
net: dev: add skb drop reasons to net/core/dev.c

In the commit c504e5c2 ("net: skb: introduce kfree_skb_reason()"),
we added the support of reporting the reasons of skb drops to kfree_skb
tracepoint. And in this series patches, reasons for skb drops are added
to the link layer, which means that 'net/core/dev.c' is our target.

Following functions are processed:

sch_handle_egress()
__dev_xmit_skb()
enqueue_to_backlog()
do_xdp_generic()
sch_handle_ingress()
__netif_receive_skb_core()

and following new drop reasons are added (what they mean can be see in
the document of them):

SKB_DROP_REASON_QDISC_EGRESS
SKB_DROP_REASON_QDISC_DROP
SKB_DROP_REASON_CPU_BACKLOG
SKB_DROP_REASON_XDP
SKB_DROP_REASON_QDISC_INGRESS
SKB_DROP_REASON_PTYPE_ABSENT

In order to add skb drop reasons to kfree_skb_list(), the function
kfree_skb_list_reason() is introduced in the 2th patch, which will be
used in __dev_xmit_skb() in the 3th patch.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add reason for skb drops to __netif_receive_skb_core() when packet_type
not found to handle the skb. For this purpose, the drop reason
SKB_DROP_REASON_PTYPE_ABSENT is introduced. Take ether packets for
example, this case mainly happens when L3 protocol is not supported.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace kfree_skb() used in sch_handle_ingress() with
kfree_skb_reason(). Following drop reasons are introduced:

SKB_DROP_REASON_TC_INGRESS
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace kfree_skb() used in do_xdp_generic() with kfree_skb_reason().
The drop reason SKB_DROP_REASON_XDP is introduced for this case.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace kfree_skb() used in enqueue_to_backlog() with
kfree_skb_reason(). The skb rop reason SKB_DROP_REASON_CPU_BACKLOG is
introduced for the case of failing to enqueue the skb to the per CPU
backlog queue. The further reason can be backlog queue full or RPS
flow limition, and I think we needn't to make further distinctions.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add reasons for skb drops to __dev_xmit_skb() by replacing
kfree_skb_list() with kfree_skb_list_reason(). The drop reason of
SKB_DROP_REASON_QDISC_DROP is introduced for qdisc enqueue fails.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

To report reasons of skb drops, introduce the function
kfree_skb_list_reason() and make kfree_skb_list() an inline call to
it. This function will be used in the next commit in
__dev_xmit_skb().
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace kfree_skb() used in sch_handle_egress() with kfree_skb_reason().
The drop reason SKB_DROP_REASON_TC_EGRESS is introduced. Considering
the code path of tc egerss, we make it distinct with the drop reason
of SKB_DROP_REASON_QDISC_DROP in the next commit.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sebastian Andrzej Siewior says:

====================
net: Convert user to netif_rx().

This is the first batch of converting netif_rx_ni() caller to
netif_rx(). The change making this possible is net-next and
netif_rx_ni() is a wrapper around netif_rx(). This is a clean up in
order to remove netif_rx_ni().

Cc: Andrew Lunn <andrew@lunn.ch>
Cc: bridge@lists.linux-foundation.org
Cc: Chris Zankel <chris@zankel.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kurt Kanzenbach <kurt@linutronix.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: Łukasz Stelmach <l.stelmach@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Steve Wahl <steve.wahl@hpe.com>
Cc: UNGLinuxDriver@microchip.com
Cc: Vivien Didelot <vivien.didelot@gmail.com>
Cc: Vladimir Oltean <olteanv@gmail.com>
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit
   baebdf48 ("net: dev: Makes sure netif_rx() can be invoked in any context.")

the function netif_rx() can be used in preemptible/thread context as
well as in interrupt context.

Use netif_rx().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit
   baebdf48 ("net: dev: Makes sure netif_rx() can be invoked in any context.")

the function netif_rx() can be used in preemptible/thread context as
well as in interrupt context.

Use netif_rx().

Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: bridge@lists.linux-foundation.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>