Merge tag 'mlx5-updates-2021-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5 subfunction support

Parav Pandit says:

This patchset introduces support for mlx5 subfunction (SF).

A subfunction is a lightweight function that has a parent PCI function on
which it is deployed. mlx5 subfunction has its own function capabilities
and its own resources. This means a subfunction has its own dedicated
queues(txq, rxq, cq, eq). These queues are neither shared nor stolen from
the parent PCI function.

When subfunction is RDMA capable, it has its own QP1, GID table and rdma
resources neither shared nor stolen from the parent PCI function.

A subfunction has dedicated window in PCI BAR space that is not shared
with the other subfunctions or parent PCI function. This ensures that all
class devices of the subfunction accesses only assigned PCI BAR space.

A Subfunction supports eswitch representation through which it supports tc
offloads. User must configure eswitch to send/receive packets from/to
subfunction port.

Subfunctions share PCI level resources such as PCI MSI-X IRQs with
their other subfunctions and/or with its parent PCI function.

Subfunction support is discussed in detail in RFC [1] and [2].
RFC [1] and extension [2] describes requirements, design and proposed
plumbing using devlink, auxiliary bus and sysfs for systemd/udev
support. Functionality of this patchset is best explained using real
examples further below.

overview:
--------
A subfunction can be created and deleted by a user using devlink port
add/delete interface.

A subfunction can be configured using devlink port function attribute
before its activated.

When a subfunction is activated, it results in an auxiliary device on
the host PCI device where it is deployed. A driver binds to the
auxiliary device that further creates supported class devices.

example subfunction usage sequence:
-----------------------------------
Change device to switchdev mode:
$ devlink dev eswitch set pci/0000:06:00.0 mode switchdev

Add a devlink port of subfunction flavour:
$ devlink port add pci/0000:06:00.0 flavour pcisf pfnum 0 sfnum 88

Configure mac address of the port function:
$ devlink port function set ens2f0npf0sf88 hw_addr 00:00:00:00:88:88

Now activate the function:
$ devlink port function set ens2f0npf0sf88 state active

Now use the auxiliary device and class devices:
$ devlink dev show
pci/0000:06:00.0
auxiliary/mlx5_core.sf.4

$ ip link show
127: ens2f0np0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 24:8a:07:b3:d1:12 brd ff:ff:ff:ff:ff:ff
    altname enp6s0f0np0
129: p0sf88: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:00:00:00:88:88 brd ff:ff:ff:ff:ff:ff

$ rdma dev show
43: rdmap6s0f0: node_type ca fw 16.29.0550 node_guid 248a:0703:00b3:d112 sys_image_guid 248a:0703:00b3:d112
44: mlx5_0: node_type ca fw 16.29.0550 node_guid 0000:00ff:fe00:8888 sys_image_guid 248a:0703:00b3:d112

After use inactivate the function:
$ devlink port function set ens2f0npf0sf88 state inactive

Now delete the subfunction port:
$ devlink port del ens2f0npf0sf88

[1] https://lore.kernel.org/netdev/20200519092258.GF4655@nanopsycho/
[2] https://marc.info/?l=linux-netdev&m=158555928517777&w=2

=================

* tag 'mlx5-updates-2021-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
  net/mlx5: Add devlink subfunction port documentation
  devlink: Extend devlink port documentation for subfunctions
  devlink: Add devlink port documentation
  net/mlx5: SF, Port function state change support
  net/mlx5: SF, Add port add delete functionality
  net/mlx5: E-switch, Add eswitch helpers for SF vport
  net/mlx5: E-switch, Prepare eswitch to handle SF vport
  net/mlx5: SF, Add auxiliary device driver
  net/mlx5: SF, Add auxiliary device support
  net/mlx5: Introduce vhca state event notifier
  devlink: Support get and set state of port function
  devlink: Support add and delete devlink port
  devlink: Introduce PCI SF port flavour and port attribute
  devlink: Prepare code to fill multiple port function attributes
====================

Link: https://lore.kernel.org/r/20210122193658.282884-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 140 insertions, 1 deletions

diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 45df5b465ba8..b955ed3450fd 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -193,7 +193,8 @@ enum port_state_policy {
 
 enum mlx5_coredev_type {
 	MLX5_COREDEV_PF,
-	MLX5_COREDEV_VF
+	MLX5_COREDEV_VF,
+	MLX5_COREDEV_SF,
 };
 
 struct mlx5_field_desc {
@@ -507,6 +508,10 @@ struct mlx5_devcom;
 struct mlx5_fw_reset;
 struct mlx5_eq_table;
 struct mlx5_irq_table;
+struct mlx5_vhca_state_notifier;
+struct mlx5_sf_dev_table;
+struct mlx5_sf_hw_table;
+struct mlx5_sf_table;
 
 struct mlx5_rate_limit {
 	u32			rate;
@@ -604,6 +609,15 @@ struct mlx5_priv {
 
 	struct mlx5_bfreg_data		bfregs;
 	struct mlx5_uars_page	       *uar;
+#ifdef CONFIG_MLX5_SF
+	struct mlx5_vhca_state_notifier *vhca_state_notifier;
+	struct mlx5_sf_dev_table *sf_dev_table;
+	struct mlx5_core_dev *parent_mdev;
+#endif
+#ifdef CONFIG_MLX5_SF_MANAGER
+	struct mlx5_sf_hw_table *sf_hw_table;
+	struct mlx5_sf_table *sf_table;
+#endif
 };
 
 enum mlx5_device_state {
diff --git a/include/net/devlink.h b/include/net/devlink.h
index 426b98e74b6e..47b4b063401b 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -94,6 +94,18 @@ struct devlink_port_pci_vf_attrs {
 };
 
 /**
+ * struct devlink_port_pci_sf_attrs - devlink port's PCI SF attributes
+ * @controller: Associated controller number
+ * @sf: Associated PCI SF for of the PCI PF for this port.
+ * @pf: Associated PCI PF number for this port.
+ */
+struct devlink_port_pci_sf_attrs {
+	u32 controller;
+	u32 sf;
+	u16 pf;
+};
+
+/**
  * struct devlink_port_attrs - devlink port object
  * @flavour: flavour of the port
  * @split: indicates if this is split port
@@ -103,6 +115,7 @@ struct devlink_port_pci_vf_attrs {
  * @phys: physical port attributes
  * @pci_pf: PCI PF port attributes
  * @pci_vf: PCI VF port attributes
+ * @pci_sf: PCI SF port attributes
  */
 struct devlink_port_attrs {
 	u8 split:1,
@@ -114,6 +127,7 @@ struct devlink_port_attrs {
 		struct devlink_port_phys_attrs phys;
 		struct devlink_port_pci_pf_attrs pci_pf;
 		struct devlink_port_pci_vf_attrs pci_vf;
+		struct devlink_port_pci_sf_attrs pci_sf;
 	};
 };
 
@@ -138,6 +152,17 @@ struct devlink_port {
 	struct mutex reporters_lock; /* Protects reporter_list */
 };
 
+struct devlink_port_new_attrs {
+	enum devlink_port_flavour flavour;
+	unsigned int port_index;
+	u32 controller;
+	u32 sfnum;
+	u16 pfnum;
+	u8 port_index_valid:1,
+	   controller_valid:1,
+	   sfnum_valid:1;
+};
+
 struct devlink_sb_pool_info {
 	enum devlink_sb_pool_type pool_type;
 	u32 size;
@@ -1353,6 +1378,79 @@ struct devlink_ops {
 	int (*port_function_hw_addr_set)(struct devlink *devlink, struct devlink_port *port,
 					 const u8 *hw_addr, int hw_addr_len,
 					 struct netlink_ext_ack *extack);
+	/**
+	 * port_new() - Add a new port function of a specified flavor
+	 * @devlink: Devlink instance
+	 * @attrs: attributes of the new port
+	 * @extack: extack for reporting error messages
+	 * @new_port_index: index of the new port
+	 *
+	 * Devlink core will call this device driver function upon user request
+	 * to create a new port function of a specified flavor and optional
+	 * attributes
+	 *
+	 * Notes:
+	 *	- Called without devlink instance lock being held. Drivers must
+	 *	  implement own means of synchronization
+	 *	- On success, drivers must register a port with devlink core
+	 *
+	 * Return: 0 on success, negative value otherwise.
+	 */
+	int (*port_new)(struct devlink *devlink,
+			const struct devlink_port_new_attrs *attrs,
+			struct netlink_ext_ack *extack,
+			unsigned int *new_port_index);
+	/**
+	 * port_del() - Delete a port function
+	 * @devlink: Devlink instance
+	 * @port_index: port function index to delete
+	 * @extack: extack for reporting error messages
+	 *
+	 * Devlink core will call this device driver function upon user request
+	 * to delete a previously created port function
+	 *
+	 * Notes:
+	 *	- Called without devlink instance lock being held. Drivers must
+	 *	  implement own means of synchronization
+	 *	- On success, drivers must unregister the corresponding devlink
+	 *	  port
+	 *
+	 * Return: 0 on success, negative value otherwise.
+	 */
+	int (*port_del)(struct devlink *devlink, unsigned int port_index,
+			struct netlink_ext_ack *extack);
+	/**
+	 * port_fn_state_get() - Get the state of a port function
+	 * @devlink: Devlink instance
+	 * @port: The devlink port
+	 * @state: Admin configured state
+	 * @opstate: Current operational state
+	 * @extack: extack for reporting error messages
+	 *
+	 * Reports the admin and operational state of a devlink port function
+	 *
+	 * Return: 0 on success, negative value otherwise.
+	 */
+	int (*port_fn_state_get)(struct devlink *devlink,
+				 struct devlink_port *port,
+				 enum devlink_port_fn_state *state,
+				 enum devlink_port_fn_opstate *opstate,
+				 struct netlink_ext_ack *extack);
+	/**
+	 * port_fn_state_set() - Set the admin state of a port function
+	 * @devlink: Devlink instance
+	 * @port: The devlink port
+	 * @state: Admin state
+	 * @extack: extack for reporting error messages
+	 *
+	 * Set the admin state of a devlink port function
+	 *
+	 * Return: 0 on success, negative value otherwise.
+	 */
+	int (*port_fn_state_set)(struct devlink *devlink,
+				 struct devlink_port *port,
+				 enum devlink_port_fn_state state,
+				 struct netlink_ext_ack *extack);
 };
 
 static inline void *devlink_priv(struct devlink *devlink)
@@ -1409,6 +1507,8 @@ void devlink_port_attrs_pci_pf_set(struct devlink_port *devlink_port, u32 contro
 				   u16 pf, bool external);
 void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port, u32 controller,
 				   u16 pf, u16 vf, bool external);
+void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port,
+				   u32 controller, u16 pf, u32 sf);
 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,
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index cf89c318f2ac..f6008b2fa60f 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -200,6 +200,10 @@ enum devlink_port_flavour {
 	DEVLINK_PORT_FLAVOUR_UNUSED, /* Port which exists in the switch, but
 				      * is not used in any way.
 				      */
+	DEVLINK_PORT_FLAVOUR_PCI_SF, /* Represents eswitch port
+				      * for the PCI SF. It is an internal
+				      * port that faces the PCI SF.
+				      */
 };
 
 enum devlink_param_cmode {
@@ -529,6 +533,7 @@ enum devlink_attr {
 	DEVLINK_ATTR_RELOAD_ACTION_INFO,        /* nested */
 	DEVLINK_ATTR_RELOAD_ACTION_STATS,       /* nested */
 
+	DEVLINK_ATTR_PORT_PCI_SF_NUMBER,	/* u32 */
 	/* add new attributes above here, update the policy in devlink.c */
 
 	__DEVLINK_ATTR_MAX,
@@ -578,9 +583,29 @@ enum devlink_resource_unit {
 enum devlink_port_function_attr {
 	DEVLINK_PORT_FUNCTION_ATTR_UNSPEC,
 	DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR,	/* binary */
+	DEVLINK_PORT_FN_ATTR_STATE,	/* u8 */
+	DEVLINK_PORT_FN_ATTR_OPSTATE,	/* u8 */
 
 	__DEVLINK_PORT_FUNCTION_ATTR_MAX,
 	DEVLINK_PORT_FUNCTION_ATTR_MAX = __DEVLINK_PORT_FUNCTION_ATTR_MAX - 1
 };
 
+enum devlink_port_fn_state {
+	DEVLINK_PORT_FN_STATE_INACTIVE,
+	DEVLINK_PORT_FN_STATE_ACTIVE,
+};
+
+/**
+ * enum devlink_port_fn_opstate - indicates operational state of the function
+ * @DEVLINK_PORT_FN_OPSTATE_ATTACHED: Driver is attached to the function.
+ * For graceful tear down of the function, after inactivation of the
+ * function, user should wait for operational state to turn DETACHED.
+ * @DEVLINK_PORT_FN_OPSTATE_DETACHED: Driver is detached from the function.
+ * It is safe to delete the port.
+ */
+enum devlink_port_fn_opstate {
+	DEVLINK_PORT_FN_OPSTATE_DETACHED,
+	DEVLINK_PORT_FN_OPSTATE_ATTACHED,
+};
+
 #endif /* _UAPI_LINUX_DEVLINK_H_ */