devlink: add shared buffer configuration

Define userspace API and drivers API for configuration of shared
buffers. Four basic objects are defined:
shared buffer - attributes are size, number of pools and TCs
pool - chunk of sharedbuffer definition, it has some size and either
       static or dynamic threshold
port pool threshold - to set per-port threshold for each pool
port tc threshold bind - to bind port and TC to specified pool
                         with threshold.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/devlink.h

@@ -24,6 +24,7 @@ struct devlink_ops;
 struct devlink {
 	struct list_head list;
 	struct list_head port_list;
+	struct list_head sb_list;
 	const struct devlink_ops *ops;
 	struct device *dev;
 	possible_net_t _net;
@@ -42,6 +43,12 @@ struct devlink_port {
 	u32 split_group;
 };
 
+struct devlink_sb_pool_info {
+	enum devlink_sb_pool_type pool_type;
+	u32 size;
+	enum devlink_sb_threshold_type threshold_type;
+};
+
 struct devlink_ops {
 	size_t priv_size;
 	int (*port_type_set)(struct devlink_port *devlink_port,
@@ -49,6 +56,28 @@ struct devlink_ops {
 	int (*port_split)(struct devlink *devlink, unsigned int port_index,
 			  unsigned int count);
 	int (*port_unsplit)(struct devlink *devlink, unsigned int port_index);
+	int (*sb_pool_get)(struct devlink *devlink, unsigned int sb_index,
+			   u16 pool_index,
+			   struct devlink_sb_pool_info *pool_info);
+	int (*sb_pool_set)(struct devlink *devlink, unsigned int sb_index,
+			   u16 pool_index, u32 size,
+			   enum devlink_sb_threshold_type threshold_type);
+	int (*sb_port_pool_get)(struct devlink_port *devlink_port,
+				unsigned int sb_index, u16 pool_index,
+				u32 *p_threshold);
+	int (*sb_port_pool_set)(struct devlink_port *devlink_port,
+				unsigned int sb_index, u16 pool_index,
+				u32 threshold);
+	int (*sb_tc_pool_bind_get)(struct devlink_port *devlink_port,
+				   unsigned int sb_index,
+				   u16 tc_index,
+				   enum devlink_sb_pool_type pool_type,
+				   u16 *p_pool_index, u32 *p_threshold);
+	int (*sb_tc_pool_bind_set)(struct devlink_port *devlink_port,
+				   unsigned int sb_index,
+				   u16 tc_index,
+				   enum devlink_sb_pool_type pool_type,
+				   u16 pool_index, u32 threshold);
 };
 
 static inline void *devlink_priv(struct devlink *devlink)
@@ -82,6 +111,11 @@ void devlink_port_type_ib_set(struct devlink_port *devlink_port,
 void devlink_port_type_clear(struct devlink_port *devlink_port);
 void devlink_port_split_set(struct devlink_port *devlink_port,
 			    u32 split_group);
+int devlink_sb_register(struct devlink *devlink, unsigned int sb_index,
+			u32 size, u16 ingress_pools_count,
+			u16 egress_pools_count, u16 ingress_tc_count,
+			u16 egress_tc_count);
+void devlink_sb_unregister(struct devlink *devlink, unsigned int sb_index);
 
 #else
 
@@ -135,6 +169,19 @@ static inline void devlink_port_split_set(struct devlink_port *devlink_port,
 {
 }
 
+static inline int devlink_sb_register(struct devlink *devlink,
+				      unsigned int sb_index, u32 size,
+				      u16 ingress_pools_count,
+				      u16 egress_pools_count, u16 tc_count)
+{
+	return 0;
+}
+
+static inline void devlink_sb_unregister(struct devlink *devlink,
+					 unsigned int sb_index)
+{
+}
+
 #endif
 
 #endif /* _NET_DEVLINK_H_ */

include/uapi/linux/devlink.h

@@ -33,6 +33,26 @@ enum devlink_command {
 	DEVLINK_CMD_PORT_SPLIT,
 	DEVLINK_CMD_PORT_UNSPLIT,
 
+	DEVLINK_CMD_SB_GET,		/* can dump */
+	DEVLINK_CMD_SB_SET,
+	DEVLINK_CMD_SB_NEW,
+	DEVLINK_CMD_SB_DEL,
+
+	DEVLINK_CMD_SB_POOL_GET,	/* can dump */
+	DEVLINK_CMD_SB_POOL_SET,
+	DEVLINK_CMD_SB_POOL_NEW,
+	DEVLINK_CMD_SB_POOL_DEL,
+
+	DEVLINK_CMD_SB_PORT_POOL_GET,	/* can dump */
+	DEVLINK_CMD_SB_PORT_POOL_SET,
+	DEVLINK_CMD_SB_PORT_POOL_NEW,
+	DEVLINK_CMD_SB_PORT_POOL_DEL,
+
+	DEVLINK_CMD_SB_TC_POOL_BIND_GET,	/* can dump */
+	DEVLINK_CMD_SB_TC_POOL_BIND_SET,
+	DEVLINK_CMD_SB_TC_POOL_BIND_NEW,
+	DEVLINK_CMD_SB_TC_POOL_BIND_DEL,
+
 	/* add new commands above here */
 
 	__DEVLINK_CMD_MAX,
@@ -46,6 +66,31 @@ enum devlink_port_type {
 	DEVLINK_PORT_TYPE_IB,
 };
 
+enum devlink_sb_pool_type {
+	DEVLINK_SB_POOL_TYPE_INGRESS,
+	DEVLINK_SB_POOL_TYPE_EGRESS,
+};
+
+/* static threshold - limiting the maximum number of bytes.
+ * dynamic threshold - limiting the maximum number of bytes
+ *   based on the currently available free space in the shared buffer pool.
+ *   In this mode, the maximum quota is calculated based
+ *   on the following formula:
+ *     max_quota = alpha / (1 + alpha) * Free_Buffer
+ *   While Free_Buffer is the amount of none-occupied buffer associated to
+ *   the relevant pool.
+ *   The value range which can be passed is 0-20 and serves
+ *   for computation of alpha by following formula:
+ *     alpha = 2 ^ (passed_value - 10)
+ */
+
+enum devlink_sb_threshold_type {
+	DEVLINK_SB_THRESHOLD_TYPE_STATIC,
+	DEVLINK_SB_THRESHOLD_TYPE_DYNAMIC,
+};
+
+#define DEVLINK_SB_THRESHOLD_TO_ALPHA_MAX 20
+
 enum devlink_attr {
 	/* don't change the order or add anything between, this is ABI! */
 	DEVLINK_ATTR_UNSPEC,
@@ -62,6 +107,18 @@ enum devlink_attr {
 	DEVLINK_ATTR_PORT_IBDEV_NAME,		/* string */
 	DEVLINK_ATTR_PORT_SPLIT_COUNT,		/* u32 */
 	DEVLINK_ATTR_PORT_SPLIT_GROUP,		/* u32 */
+	DEVLINK_ATTR_SB_INDEX,			/* u32 */
+	DEVLINK_ATTR_SB_SIZE,			/* u32 */
+	DEVLINK_ATTR_SB_INGRESS_POOL_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_EGRESS_POOL_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_INGRESS_TC_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_EGRESS_TC_COUNT,	/* u16 */
+	DEVLINK_ATTR_SB_POOL_INDEX,		/* u16 */
+	DEVLINK_ATTR_SB_POOL_TYPE,		/* u8 */
+	DEVLINK_ATTR_SB_POOL_SIZE,		/* u32 */
+	DEVLINK_ATTR_SB_POOL_THRESHOLD_TYPE,	/* u8 */
+	DEVLINK_ATTR_SB_THRESHOLD,		/* u32 */
+	DEVLINK_ATTR_SB_TC_INDEX,		/* u16 */
 
 	/* add new attributes above here, update the policy in devlink.c */