diff mbox series

[v3,net-next,1/8] net/sched: query offload capabilities through ndo_setup_tc()

Message ID 20220927234746.1823648-2-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Add tc-taprio support for queueMaxSDU | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 4377 this patch: 4377
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 1057 this patch: 1057
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4566 this patch: 4566
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 50 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean Sept. 27, 2022, 11:47 p.m. UTC 
When adding optional new features to Qdisc offloads, existing drivers
must reject the new configuration until they are coded up to act on it.

Since modifying all drivers in lockstep with the changes in the Qdisc
can create problems of its own, it would be nice if there existed an
automatic opt-in mechanism for offloading optional features.

Jakub proposes that we multiplex one more kind of call through
ndo_setup_tc(): one where the driver populates a Qdisc-specific
capability structure.

First user will be taprio in further changes. Here we are introducing
the definitions for the base functionality.

Link: https://patchwork.kernel.org/project/netdevbpf/patch/20220923163310.3192733-3-vladimir.oltean@nxp.com/
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
v2->v3: patch is new

 include/linux/netdevice.h |  1 +
 include/net/pkt_sched.h   |  5 +++++
 include/net/sch_generic.h |  3 +++
 net/sched/sch_api.c       | 17 +++++++++++++++++
 4 files changed, 26 insertions(+)
diff mbox series

Patch

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9f42fc871c3b..b175d6769f72 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -940,6 +940,7 @@  struct net_device_path_ctx {
 };
 
 enum tc_setup_type {
+	TC_QUERY_CAPS,
 	TC_SETUP_QDISC_MQPRIO,
 	TC_SETUP_CLSU32,
 	TC_SETUP_CLSFLOWER,
diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h
index 2ff80cd04c5c..34600292fdfb 100644
--- a/include/net/pkt_sched.h
+++ b/include/net/pkt_sched.h
@@ -141,6 +141,11 @@  static inline struct net *qdisc_net(struct Qdisc *q)
 	return dev_net(q->dev_queue->dev);
 }
 
+struct tc_query_caps_base {
+	enum tc_setup_type type;
+	void *caps;
+};
+
 struct tc_cbs_qopt_offload {
 	u8 enable;
 	s32 queue;
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 32819299937d..d5517719af4e 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -677,6 +677,9 @@  qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
 {
 }
 #endif
+void qdisc_offload_query_caps(struct net_device *dev,
+			      enum tc_setup_type type,
+			      void *caps, size_t caps_len);
 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 			  const struct Qdisc_ops *ops,
 			  struct netlink_ext_ack *extack);
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index db1569fac57c..7c15f1f3da17 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -868,6 +868,23 @@  void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
 }
 EXPORT_SYMBOL(qdisc_offload_graft_helper);
 
+void qdisc_offload_query_caps(struct net_device *dev,
+			      enum tc_setup_type type,
+			      void *caps, size_t caps_len)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+	struct tc_query_caps_base base = {
+		.type = type,
+		.caps = caps,
+	};
+
+	memset(caps, 0, caps_len);
+
+	if (ops->ndo_setup_tc)
+		ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base);
+}
+EXPORT_SYMBOL(qdisc_offload_query_caps);
+
 static void qdisc_offload_graft_root(struct net_device *dev,
 				     struct Qdisc *new, struct Qdisc *old,
 				     struct netlink_ext_ack *extack)