Merge branch 'net-dpipe'

Jiri Pirko says:

====================
Add support for pipeline debug (dpipe)

Arkadi says:

While doing the hardware offloading process much of the hardware
specifics cannot be presented. An example for such is the routing
LPM algorithm which differ in hardware implementation from the
kernel software implementation. The only information the user receives
is whether specific route is offloaded or not, but he cannot really
understand the underlying implementation nor get the specific statistics
related to that process.

Another example is ACL offload using TC which is commonly implemented
using TCAM memory. Currently there is no capability to gain visibility
into the TCAM structure and to debug suboptimal resource allocation.

This patchset introduces capability for exporting the ASICs pipeline
abstraction via devlink infrastructure, which should serve as an
complementary tool. This infrastructure allows the user to get visibility
into the ASIC by modeling it as a set of match/action tables.

The main objects defined:
Table - abstraction for a single pipeline stage. Contains the
        available match/actions and counter availability.
Entry - entry in a specific table with specific matches/actions
        values and dedicated counter.
Header/field - tuples which describes the tables behavior.

As an example one of the ASIC's L3 blocks will be modeled. The egress
rif (router interface) table is the final step in the L3 pipeline
processing which does match on the internal rif index which was
determined before by the routing logic. The erif table determines
whether to forward or drop the packet and updates the corresponding
rif L3 statistics.

To expose this internal resources a special metadata header will
be introduced that describes the internal information gathered by
the ASIC's pipeline and contains the following fields: rif_port_index,
forward and drop.

Some internal hardware resources have direct mapping to kernel
objects. For example the rif_port_index is mapped to the net-devices
ifindex. By providing this mapping the users gains visibility into
the offloading process.

Follow-up work will include exporting more L3 tables which will give
visibility into the routing process.

First stage is adding support for dpipe in devlink. Next add support
in spectrum driver. Finally implement egress router interface
(erif) table for spectrum ASIC as an example.

---
v1->v2: Please see individual patches
====================

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

2 files changed, 325 insertions, 1 deletions

diff --git a/include/net/devlink.h b/include/net/devlink.h
index d29e5fc82582..24de13f8c94f 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -25,6 +25,8 @@ struct devlink {
 	struct list_head list;
 	struct list_head port_list;
 	struct list_head sb_list;
+	struct list_head dpipe_table_list;
+	struct devlink_dpipe_headers *dpipe_headers;
 	const struct devlink_ops *ops;
 	struct device *dev;
 	possible_net_t _net;
@@ -49,6 +51,178 @@ struct devlink_sb_pool_info {
 	enum devlink_sb_threshold_type threshold_type;
 };
 
+/**
+ * struct devlink_dpipe_field - dpipe field object
+ * @name: field name
+ * @id: index inside the headers field array
+ * @bitwidth: bitwidth
+ * @mapping_type: mapping type
+ */
+struct devlink_dpipe_field {
+	const char *name;
+	unsigned int id;
+	unsigned int bitwidth;
+	enum devlink_dpipe_field_mapping_type mapping_type;
+};
+
+/**
+ * struct devlink_dpipe_header - dpipe header object
+ * @name: header name
+ * @id: index, global/local detrmined by global bit
+ * @fields: fields
+ * @fields_count: number of fields
+ * @global: indicates if header is shared like most protocol header
+ *	    or driver specific
+ */
+struct devlink_dpipe_header {
+	const char *name;
+	unsigned int id;
+	struct devlink_dpipe_field *fields;
+	unsigned int fields_count;
+	bool global;
+};
+
+/**
+ * struct devlink_dpipe_match - represents match operation
+ * @type: type of match
+ * @header_index: header index (packets can have several headers of same
+ *		  type like in case of tunnels)
+ * @header: header
+ * @fieled_id: field index
+ */
+struct devlink_dpipe_match {
+	enum devlink_dpipe_match_type type;
+	unsigned int header_index;
+	struct devlink_dpipe_header *header;
+	unsigned int field_id;
+};
+
+/**
+ * struct devlink_dpipe_action - represents action operation
+ * @type: type of action
+ * @header_index: header index (packets can have several headers of same
+ *		  type like in case of tunnels)
+ * @header: header
+ * @fieled_id: field index
+ */
+struct devlink_dpipe_action {
+	enum devlink_dpipe_action_type type;
+	unsigned int header_index;
+	struct devlink_dpipe_header *header;
+	unsigned int field_id;
+};
+
+/**
+ * struct devlink_dpipe_value - represents value of match/action
+ * @action: action
+ * @match: match
+ * @mapping_value: in case the field has some mapping this value
+ *                 specified the mapping value
+ * @mapping_valid: specify if mapping value is valid
+ * @value_size: value size
+ * @value: value
+ * @mask: bit mask
+ */
+struct devlink_dpipe_value {
+	union {
+		struct devlink_dpipe_action *action;
+		struct devlink_dpipe_match *match;
+	};
+	unsigned int mapping_value;
+	bool mapping_valid;
+	unsigned int value_size;
+	void *value;
+	void *mask;
+};
+
+/**
+ * struct devlink_dpipe_entry - table entry object
+ * @index: index of the entry in the table
+ * @match_values: match values
+ * @matche_values_count: count of matches tuples
+ * @action_values: actions values
+ * @action_values_count: count of actions values
+ * @counter: value of counter
+ * @counter_valid: Specify if value is valid from hardware
+ */
+struct devlink_dpipe_entry {
+	u64 index;
+	struct devlink_dpipe_value *match_values;
+	unsigned int match_values_count;
+	struct devlink_dpipe_value *action_values;
+	unsigned int action_values_count;
+	u64 counter;
+	bool counter_valid;
+};
+
+/**
+ * struct devlink_dpipe_dump_ctx - context provided to driver in order
+ *				   to dump
+ * @info: info
+ * @cmd: devlink command
+ * @skb: skb
+ * @nest: top attribute
+ * @hdr: hdr
+ */
+struct devlink_dpipe_dump_ctx {
+	struct genl_info *info;
+	enum devlink_command cmd;
+	struct sk_buff *skb;
+	struct nlattr *nest;
+	void *hdr;
+};
+
+struct devlink_dpipe_table_ops;
+
+/**
+ * struct devlink_dpipe_table - table object
+ * @priv: private
+ * @name: table name
+ * @size: maximum number of entries
+ * @counters_enabled: indicates if counters are active
+ * @counter_control_extern: indicates if counter control is in dpipe or
+ *			    external tool
+ * @table_ops: table operations
+ * @rcu: rcu
+ */
+struct devlink_dpipe_table {
+	void *priv;
+	struct list_head list;
+	const char *name;
+	u64 size;
+	bool counters_enabled;
+	bool counter_control_extern;
+	struct devlink_dpipe_table_ops *table_ops;
+	struct rcu_head rcu;
+};
+
+/**
+ * struct devlink_dpipe_table_ops - dpipe_table ops
+ * @actions_dump - dumps all tables actions
+ * @matches_dump - dumps all tables matches
+ * @entries_dump - dumps all active entries in the table
+ * @counters_set_update - when changing the counter status hardware sync
+ *			  maybe needed to allocate/free counter related
+ *			  resources
+ */
+struct devlink_dpipe_table_ops {
+	int (*actions_dump)(void *priv, struct sk_buff *skb);
+	int (*matches_dump)(void *priv, struct sk_buff *skb);
+	int (*entries_dump)(void *priv, bool counters_enabled,
+			    struct devlink_dpipe_dump_ctx *dump_ctx);
+	int (*counters_set_update)(void *priv, bool enable);
+};
+
+/**
+ * struct devlink_dpipe_headers - dpipe headers
+ * @headers - header array can be shared (global bit) or driver specific
+ * @headers_count - count of headers
+ */
+struct devlink_dpipe_headers {
+	struct devlink_dpipe_header **headers;
+	unsigned int headers_count;
+};
+
 struct devlink_ops {
 	int (*port_type_set)(struct devlink_port *devlink_port,
 			     enum devlink_port_type port_type);
@@ -132,6 +306,26 @@ int devlink_sb_register(struct devlink *devlink, unsigned int sb_index,
 			u16 egress_pools_count, u16 ingress_tc_count,
 			u16 egress_tc_count);
 void devlink_sb_unregister(struct devlink *devlink, unsigned int sb_index);
+int devlink_dpipe_table_register(struct devlink *devlink,
+				 const char *table_name,
+				 struct devlink_dpipe_table_ops *table_ops,
+				 void *priv, u64 size,
+				 bool counter_control_extern);
+void devlink_dpipe_table_unregister(struct devlink *devlink,
+				    const char *table_name);
+int devlink_dpipe_headers_register(struct devlink *devlink,
+				   struct devlink_dpipe_headers *dpipe_headers);
+void devlink_dpipe_headers_unregister(struct devlink *devlink);
+bool devlink_dpipe_table_counter_enabled(struct devlink *devlink,
+					 const char *table_name);
+int devlink_dpipe_entry_ctx_prepare(struct devlink_dpipe_dump_ctx *dump_ctx);
+int devlink_dpipe_entry_ctx_append(struct devlink_dpipe_dump_ctx *dump_ctx,
+				   struct devlink_dpipe_entry *entry);
+int devlink_dpipe_entry_ctx_close(struct devlink_dpipe_dump_ctx *dump_ctx);
+int devlink_dpipe_action_put(struct sk_buff *skb,
+			     struct devlink_dpipe_action *action);
+int devlink_dpipe_match_put(struct sk_buff *skb,
+			    struct devlink_dpipe_match *match);
 
 #else
 
@@ -200,6 +394,71 @@ static inline void devlink_sb_unregister(struct devlink *devlink,
 {
 }
 
+static inline int
+devlink_dpipe_table_register(struct devlink *devlink,
+			     const char *table_name,
+			     struct devlink_dpipe_table_ops *table_ops,
+			     void *priv, u64 size,
+			     bool counter_control_extern)
+{
+	return 0;
+}
+
+static inline void devlink_dpipe_table_unregister(struct devlink *devlink,
+						  const char *table_name)
+{
+}
+
+static inline int devlink_dpipe_headers_register(struct devlink *devlink,
+						 struct devlink_dpipe_headers *
+						 dpipe_headers)
+{
+	return 0;
+}
+
+static inline void devlink_dpipe_headers_unregister(struct devlink *devlink)
+{
+}
+
+static inline bool devlink_dpipe_table_counter_enabled(struct devlink *devlink,
+						       const char *table_name)
+{
+	return false;
+}
+
+static inline int
+devlink_dpipe_entry_ctx_prepare(struct devlink_dpipe_dump_ctx *dump_ctx)
+{
+	return 0;
+}
+
+static inline int
+devlink_dpipe_entry_ctx_append(struct devlink_dpipe_dump_ctx *dump_ctx,
+			       struct devlink_dpipe_entry *entry)
+{
+	return 0;
+}
+
+static inline int
+devlink_dpipe_entry_ctx_close(struct devlink_dpipe_dump_ctx *dump_ctx)
+{
+	return 0;
+}
+
+static inline int
+devlink_dpipe_action_put(struct sk_buff *skb,
+			 struct devlink_dpipe_action *action)
+{
+	return 0;
+}
+
+static inline int
+devlink_dpipe_match_put(struct sk_buff *skb,
+			struct devlink_dpipe_match *match)
+{
+	return 0;
+}
+
 #endif
 
 #endif /* _NET_DEVLINK_H_ */
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 0f1f3a12e23c..b47bee277347 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -65,8 +65,12 @@ enum devlink_command {
 #define DEVLINK_CMD_ESWITCH_MODE_SET /* obsolete, never use this! */ \
 	DEVLINK_CMD_ESWITCH_SET
 
-	/* add new commands above here */
+	DEVLINK_CMD_DPIPE_TABLE_GET,
+	DEVLINK_CMD_DPIPE_ENTRIES_GET,
+	DEVLINK_CMD_DPIPE_HEADERS_GET,
+	DEVLINK_CMD_DPIPE_TABLE_COUNTERS_SET,
 
+	/* add new commands above here */
 	__DEVLINK_CMD_MAX,
 	DEVLINK_CMD_MAX = __DEVLINK_CMD_MAX - 1
 };
@@ -148,10 +152,71 @@ enum devlink_attr {
 	DEVLINK_ATTR_ESWITCH_MODE,		/* u16 */
 	DEVLINK_ATTR_ESWITCH_INLINE_MODE,	/* u8 */
 
+	DEVLINK_ATTR_DPIPE_TABLES,		/* nested */
+	DEVLINK_ATTR_DPIPE_TABLE,		/* nested */
+	DEVLINK_ATTR_DPIPE_TABLE_NAME,		/* string */
+	DEVLINK_ATTR_DPIPE_TABLE_SIZE,		/* u64 */
+	DEVLINK_ATTR_DPIPE_TABLE_MATCHES,	/* nested */
+	DEVLINK_ATTR_DPIPE_TABLE_ACTIONS,	/* nested */
+	DEVLINK_ATTR_DPIPE_TABLE_COUNTERS_ENABLED,	/* u8 */
+
+	DEVLINK_ATTR_DPIPE_ENTRIES,		/* nested */
+	DEVLINK_ATTR_DPIPE_ENTRY,		/* nested */
+	DEVLINK_ATTR_DPIPE_ENTRY_INDEX,		/* u64 */
+	DEVLINK_ATTR_DPIPE_ENTRY_MATCH_VALUES,	/* nested */
+	DEVLINK_ATTR_DPIPE_ENTRY_ACTION_VALUES,	/* nested */
+	DEVLINK_ATTR_DPIPE_ENTRY_COUNTER,	/* u64 */
+
+	DEVLINK_ATTR_DPIPE_MATCH,		/* nested */
+	DEVLINK_ATTR_DPIPE_MATCH_VALUE,		/* nested */
+	DEVLINK_ATTR_DPIPE_MATCH_TYPE,		/* u32 */
+
+	DEVLINK_ATTR_DPIPE_ACTION,		/* nested */
+	DEVLINK_ATTR_DPIPE_ACTION_VALUE,	/* nested */
+	DEVLINK_ATTR_DPIPE_ACTION_TYPE,		/* u32 */
+
+	DEVLINK_ATTR_DPIPE_VALUE,
+	DEVLINK_ATTR_DPIPE_VALUE_MASK,
+	DEVLINK_ATTR_DPIPE_VALUE_MAPPING,	/* u32 */
+
+	DEVLINK_ATTR_DPIPE_HEADERS,		/* nested */
+	DEVLINK_ATTR_DPIPE_HEADER,		/* nested */
+	DEVLINK_ATTR_DPIPE_HEADER_NAME,		/* string */
+	DEVLINK_ATTR_DPIPE_HEADER_ID,		/* u32 */
+	DEVLINK_ATTR_DPIPE_HEADER_FIELDS,	/* nested */
+	DEVLINK_ATTR_DPIPE_HEADER_GLOBAL,	/* u8 */
+	DEVLINK_ATTR_DPIPE_HEADER_INDEX,	/* u32 */
+
+	DEVLINK_ATTR_DPIPE_FIELD,		/* nested */
+	DEVLINK_ATTR_DPIPE_FIELD_NAME,		/* string */
+	DEVLINK_ATTR_DPIPE_FIELD_ID,		/* u32 */
+	DEVLINK_ATTR_DPIPE_FIELD_BITWIDTH,	/* u32 */
+	DEVLINK_ATTR_DPIPE_FIELD_MAPPING_TYPE,	/* u32 */
+
+	DEVLINK_ATTR_PAD,
+
 	/* add new attributes above here, update the policy in devlink.c */
 
 	__DEVLINK_ATTR_MAX,
 	DEVLINK_ATTR_MAX = __DEVLINK_ATTR_MAX - 1
 };
 
+/* Mapping between internal resource described by the field and system
+ * structure
+ */
+enum devlink_dpipe_field_mapping_type {
+	DEVLINK_DPIPE_FIELD_MAPPING_TYPE_NONE,
+	DEVLINK_DPIPE_FIELD_MAPPING_TYPE_IFINDEX,
+};
+
+/* Match type - specify the type of the match */
+enum devlink_dpipe_match_type {
+	DEVLINK_DPIPE_MATCH_TYPE_FIELD_EXACT,
+};
+
+/* Action type - specify the action type */
+enum devlink_dpipe_action_type {
+	DEVLINK_DPIPE_ACTION_TYPE_FIELD_MODIFY,
+};
+
 #endif /* _UAPI_LINUX_DEVLINK_H_ */