ice: Add support for switch filter programming

A VSI needs traffic directed towards it. This is done by programming
filter rules on the switch (embedded vSwitch) element in the hardware,
which connects the VSI to the ingress/egress port.

This patch introduces data structures and functions necessary to add
remove or update switch rules on the switch element. This is a pretty low
level function that is generic enough to add a whole range of filters.

This patch also introduces two top level functions ice_add_mac and
ice_remove mac which through a series of intermediate helper functions
eventually call ice_aq_sw_rules to add/delete simple MAC based filters.
It's worth noting that one invocation of ice_add_mac/ice_remove_mac
is capable of adding/deleting multiple MAC filters.

Also worth noting is the fact that the driver maintains a list of currently
active filters, so every filter addition/removal causes an update to this
list. This is done for a couple of reasons:

1) If two VSIs try to add the same filters, we need to detect it and do
   things a little differently (i.e. use VSI lists, described below) as
   the same filter can't be added more than once.

2) In the event of a hardware reset we can simply walk through this list
   and restore the filters.

VSI Lists:
In a multi-VSI situation, it's possible that multiple VSIs want to add the
same filter rule. For example, two VSIs that want to receive broadcast
traffic would both add a filter for destination MAC ff:ff:ff:ff:ff:ff.
This can become cumbersome to maintain and so this is handled using a
VSI list.

A VSI list is resource that can be allocated in the hardware using the
ice_aq_alloc_free_res admin queue command. Simply put, a VSI list can
be thought of as a subscription list containing a set of VSIs to which
the packet should be forwarded, should the filter match.

For example, if VSI-0 has already added a broadcast filter, and VSI-1
wants to do the same thing, the filter creation flow will detect this,
allocate a VSI list and update the switch rule so that broadcast traffic
will now be forwarded to the VSI list which contains VSI-0 and VSI-1.

Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_status.h b/drivers/net/ethernet/intel/ice/ice_status.h
index 144712db1ad2..365dfb86dcb9 100644
--- a/drivers/net/ethernet/intel/ice/ice_status.h
+++ b/drivers/net/ethernet/intel/ice/ice_status.h
@@ -7,6 +7,7 @@
 /* Error Codes */
 enum ice_status {
 	ICE_ERR_PARAM				= -1,
+	ICE_ERR_NOT_IMPL			= -2,
 	ICE_ERR_NOT_READY			= -3,
 	ICE_ERR_INVAL_SIZE			= -6,
 	ICE_ERR_DEVICE_NOT_SUPPORTED		= -8,
@@ -15,6 +16,8 @@ enum ice_status {
 	ICE_ERR_NO_MEMORY			= -11,
 	ICE_ERR_CFG				= -12,
 	ICE_ERR_OUT_OF_RANGE			= -13,
+	ICE_ERR_ALREADY_EXISTS			= -14,
+	ICE_ERR_DOES_NOT_EXIST			= -15,
 	ICE_ERR_BUF_TOO_SHORT			= -52,
 	ICE_ERR_NVM_BLANK_MODE			= -53,
 	ICE_ERR_AQ_ERROR			= -100,