treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE (part 1)

Based on the normalized pattern:

this program is free software you may redistribute it and/or modify it
under the terms of the gnu general public license as published by the
free software foundation version 2 of the license the software is
provided as is without warranty of any kind express or implied
including but not limited to the warranties of merchantability fitness
for a particular purpose and noninfringement in no event shall the
authors or copyright holders be liable for any claim damages or other
liability whether in an action of contract tort or otherwise arising
from out of or in connection with the software or the use or other
dealings in the software

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

enic: Remove local ndo_busy_poll() implementation.

We do polling generically these days.

Signed-off-by: David S. Miller <davem@davemloft.net>

enic: use atomic_t instead of spin_lock in busy poll

We use spinlock to access a single flag. We can avoid spin_locks by using
atomic variable and atomic_cmpxchg(). Use atomic_cmpxchg to set the flag
for idle to poll. And a simple atomic_set to unlock (set idle from poll).

In napi poll, if gro is enabled, we call napi_gro_receive() to deliver the
packets. Before we call napi_complete(), i.e while re-polling, if low
latency busy poll is called, we use netif_receive_skb() to deliver the packets.
At this point if there are some skb's held in GRO, busy poll could deliver the
packets out of order. So we call napi_gro_flush() to flush skbs before we
move the napi poll to idle.

Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enic: add low latency socket busy_poll support

This patch adds support for low latency busy_poll.

* Introduce drivers ndo_busy_poll function enic_busy_poll, which is called by
socket waiting for data.

* Introduce locking between napi_poll nad busy_poll

* enic_busy_poll cleans up all the rx pkts possible. While in busy_poll, rq
holds the state ENIC_POLL_STATE_POLL. While in napi_poll, rq holds the state
ENIC_POLL_STATE_NAPI.

* in napi_poll we return if we are in busy_poll. Incase of INTx & msix, we just
service wq and return if busy_poll is going on.

Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net: enic: Adding support for Cisco Low Latency NIC

This patch,
- Adds new firmware commands for the new Cisco Low Latency NIC
(aka. USNIC).

Signed-off-by: Neel Patel <neepatel@cisco.com>
Signed-off-by: Nishank Trivedi <nistrive@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enic: Move the Cisco driver

Move the Cisco driver into drivers/net/ethernet/cisco/ and make the
necessary Kconfig and Makefile changes.

CC: Christian Benvenuti <benve@cisco.com>
CC: Vasanthy Kolluri <vkolluri@cisco.com>
CC: Roopa Prabhu <roprabhu@cisco.com>
CC: David Wang <dwang2@cisco.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>