Merge branch 'devlink-rate-objects'

Dmytro Linkin says:

====================
devlink: rate objects API

Resending without RFC.

Currently kernel provides a way to change tx rate of single VF in
switchdev mode via tc-police action. When lots of VFs are configured
management of theirs rates becomes non-trivial task and some grouping
mechanism is required. Implementing such grouping in tc-police will bring
flow related limitations and unwanted complications, like:
- tc-police is a policer and there is a user request for a traffic
  shaper, so shared tc-police action is not suitable;
- flows requires net device to be placed on, means "groups" wouldn't
  have net device instance itself. Taking into the account previous
  point was reviewed a sollution, when representor have a policer and
  the driver use a shaper if qdisc contains group of VFs - such approach
  ugly, compilated and misleading;
- TC is ingress only, while configuring "other" side of the wire looks
  more like a "real" picture where shaping is outside of the steering
  world, similar to "ip link" command;

According to that devlink is the most appropriate place.

This series introduces devlink API for managing tx rate of single devlink
port or of a group by invoking callbacks (see below) of corresponding
driver. Also devlink port or a group can be added to the parent group,
where driver responsible to handle rates of a group elements. To achieve
all of that new rate object is added. It can be one of the two types:
- leaf - represents a single devlink port; created/destroyed by the
  driver and bound to the devlink port. As example, some driver may
  create leaf rate object for every devlink port associated with VF.
  Since leaf have 1to1 mapping to it's devlink port, in user space it is
  referred as pci/<bus_addr>/<port_index>;
- node - represents a group of rate objects; created/deleted by request
  from the userspace; initially empty (no rate objects added). In
  userspace it is referred as pci/<bus_addr>/<node_name>, where node name
  can be any, except decimal number, to avoid collisions with leafs.

devlink_ops extended with following callbacks:
- rate_{leaf|node}_tx_{share|max}_set
- rate_node_{new|del}
- rate_{leaf|node}_parent_set

KAPI provides:
- creation/destruction of the leaf rate object associated with devlink
  port
- destruction of rate nodes to allow a vendor driver to free allocated
  resources on driver removal or due to the other reasons when nodes
  destruction required

UAPI provides:
- dumping all or single rate objects
- setting tx_{share|max} of rate object of any type
- creating/deleting node rate object
- setting/unsetting parent of any rate object

Added devlink rate object support for netdevsim driver

Issues/open questions:
- Does user need DEVLINK_CMD_RATE_DEL_ALL_CHILD command to clean all
  children of particular parent node? For example:
  $ devlink port function rate flush netdevsim/netdevsim10/group
- priv pointer passed to the callbacks is a source of bugs; in leaf case
  driver can embed rate object into internal structure and use
  container_of() on it; in node case it cannot be done since nodes are
  created from userspace

v1->v2:
- fixed kernel-doc for devlink_rate_leaf_{create|destroy}()
- s/func/function/ for all devlink port command occurences

v2->v3:
- devlink:
  - added devlink_rate_nodes_destroy() function
- netdevsim:
  - added call of devlink_rate_nodes_destroy() function
====================

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

1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 7ff24e03577b..cdfdf2a99578 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -197,11 +197,22 @@ static inline void nsim_dev_psample_exit(struct nsim_dev *nsim_dev)
 }
 #endif
 
+enum nsim_dev_port_type {
+	NSIM_DEV_PORT_TYPE_PF,
+	NSIM_DEV_PORT_TYPE_VF,
+};
+
+#define NSIM_DEV_VF_PORT_INDEX_BASE 128
+#define NSIM_DEV_VF_PORT_INDEX_MAX UINT_MAX
+
 struct nsim_dev_port {
 	struct list_head list;
 	struct devlink_port devlink_port;
 	unsigned int port_index;
+	enum nsim_dev_port_type port_type;
 	struct dentry *ddir;
+	struct dentry *rate_parent;
+	char *parent_name;
 	struct netdevsim *ns;
 };
 
@@ -212,6 +223,8 @@ struct nsim_dev {
 	struct dentry *ddir;
 	struct dentry *ports_ddir;
 	struct dentry *take_snapshot;
+	struct dentry *max_vfs;
+	struct dentry *nodes_ddir;
 	struct bpf_offload_dev *bpf_dev;
 	bool bpf_bind_accept;
 	bool bpf_bind_verifier_accept;
@@ -247,8 +260,22 @@ struct nsim_dev {
 		u32 sleep;
 	} udp_ports;
 	struct nsim_dev_psample *psample;
+	u16 esw_mode;
 };
 
+int nsim_esw_legacy_enable(struct nsim_dev *nsim_dev, struct netlink_ext_ack *extack);
+int nsim_esw_switchdev_enable(struct nsim_dev *nsim_dev, struct netlink_ext_ack *extack);
+
+static inline bool nsim_esw_mode_is_legacy(struct nsim_dev *nsim_dev)
+{
+	return nsim_dev->esw_mode == DEVLINK_ESWITCH_MODE_LEGACY;
+}
+
+static inline bool nsim_esw_mode_is_switchdev(struct nsim_dev *nsim_dev)
+{
+	return nsim_dev->esw_mode == DEVLINK_ESWITCH_MODE_SWITCHDEV;
+}
+
 static inline struct net *nsim_dev_net(struct nsim_dev *nsim_dev)
 {
 	return devlink_net(priv_to_devlink(nsim_dev));
@@ -259,8 +286,10 @@ void nsim_dev_exit(void);
 int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev);
 void nsim_dev_remove(struct nsim_bus_dev *nsim_bus_dev);
 int nsim_dev_port_add(struct nsim_bus_dev *nsim_bus_dev,
+		      enum nsim_dev_port_type type,
 		      unsigned int port_index);
 int nsim_dev_port_del(struct nsim_bus_dev *nsim_bus_dev,
+		      enum nsim_dev_port_type type,
 		      unsigned int port_index);
 
 struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
@@ -269,6 +298,23 @@ void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *fib_data);
 u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
 		     enum nsim_resource_id res_id, bool max);
 
+ssize_t nsim_bus_dev_max_vfs_read(struct file *file,
+				  char __user *data,
+				  size_t count, loff_t *ppos);
+ssize_t nsim_bus_dev_max_vfs_write(struct file *file,
+				   const char __user *data,
+				   size_t count, loff_t *ppos);
+void nsim_bus_dev_vfs_disable(struct nsim_bus_dev *nsim_bus_dev);
+
+static inline bool nsim_dev_port_is_pf(struct nsim_dev_port *nsim_dev_port)
+{
+	return nsim_dev_port->port_type == NSIM_DEV_PORT_TYPE_PF;
+}
+
+static inline bool nsim_dev_port_is_vf(struct nsim_dev_port *nsim_dev_port)
+{
+	return nsim_dev_port->port_type == NSIM_DEV_PORT_TYPE_VF;
+}
 #if IS_ENABLED(CONFIG_XFRM_OFFLOAD)
 void nsim_ipsec_init(struct netdevsim *ns);
 void nsim_ipsec_teardown(struct netdevsim *ns);
@@ -308,7 +354,9 @@ struct nsim_bus_dev {
 	struct net *initial_net; /* Purpose of this is to carry net pointer
 				  * during the probe time only.
 				  */
+	unsigned int max_vfs;
 	unsigned int num_vfs;
+	struct mutex vfs_lock;  /* Protects vfconfigs */
 	struct nsim_vf_config *vfconfigs;
 	/* Lock for devlink->reload_enabled in netdevsim module */
 	struct mutex nsim_bus_reload_lock;