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Message-ID: <20240417142028.2171-4-michal.swiatkowski@linux.intel.com>
Date: Wed, 17 Apr 2024 16:20:23 +0200
From: Michal Swiatkowski <michal.swiatkowski@...ux.intel.com>
To: intel-wired-lan@...ts.osuosl.org
Cc: netdev@...r.kernel.org,
	jacob.e.keller@...el.com,
	michal.kubiak@...el.com,
	maciej.fijalkowski@...el.com,
	sridhar.samudrala@...el.com,
	przemyslaw.kitszel@...el.com,
	wojciech.drewek@...el.com,
	pio.raczynski@...il.com,
	jiri@...dia.com,
	mateusz.polchlopek@...el.com
Subject: [iwl-next v4 3/8] ice: add basic devlink subfunctions support

From: Piotr Raczynski <piotr.raczynski@...el.com>

Implement devlink port handlers responsible for ethernet type devlink
subfunctions. Create subfunction devlink port and setup all resources
needed for a subfunction netdev to operate. Configure new VSI for each
new subfunction, initialize and configure interrupts and Tx/Rx resources.
Set correct MAC filters and create new netdev.

For now, subfunction is limited to only one Tx/Rx queue pair.

Only allocate new subfunction VSI with devlink port new command.
This makes sure that real resources are configured only when a new
subfunction gets activated. Allocate and free subfunction MSIX
interrupt vectors using new API calls with pci_msix_alloc_irq_at
and pci_msix_free_irq.

Support both automatic and manual subfunction numbers. If no subfunction
number is provided, use xa_alloc to pick a number automatically. This
will find the first free index and use that as the number. This reduces
burden on users in the simple case where a specific number is not
required. It may also be slightly faster to check that a number exists
since xarray lookup should be faster than a linear scan of the dyn_ports
xarray.

Reviewed-by: Wojciech Drewek <wojciech.drewek@...el.com>
Co-developed-by: Jacob Keller <jacob.e.keller@...el.com>
Signed-off-by: Jacob Keller <jacob.e.keller@...el.com>
Signed-off-by: Piotr Raczynski <piotr.raczynski@...el.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@...ux.intel.com>
---
 .../net/ethernet/intel/ice/devlink/devlink.c  |   3 +
 .../ethernet/intel/ice/devlink/devlink_port.c | 347 ++++++++++++++++++
 .../ethernet/intel/ice/devlink/devlink_port.h |  30 ++
 drivers/net/ethernet/intel/ice/ice.h          |   4 +
 drivers/net/ethernet/intel/ice/ice_lib.c      |   5 +-
 drivers/net/ethernet/intel/ice/ice_lib.h      |   2 +
 drivers/net/ethernet/intel/ice/ice_main.c     |   9 +-
 7 files changed, 397 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink.c b/drivers/net/ethernet/intel/ice/devlink/devlink.c
index b179eaccc774..661af04c8eef 100644
--- a/drivers/net/ethernet/intel/ice/devlink/devlink.c
+++ b/drivers/net/ethernet/intel/ice/devlink/devlink.c
@@ -6,6 +6,7 @@
 #include "ice.h"
 #include "ice_lib.h"
 #include "devlink.h"
+#include "devlink_port.h"
 #include "ice_eswitch.h"
 #include "ice_fw_update.h"
 #include "ice_dcb_lib.h"
@@ -1281,6 +1282,8 @@ static const struct devlink_ops ice_devlink_ops = {
 
 	.rate_leaf_parent_set = ice_devlink_set_parent,
 	.rate_node_parent_set = ice_devlink_set_parent,
+
+	.port_new = ice_devlink_port_new,
 };
 
 static int
diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink_port.c b/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
index 13e6790d3cae..d80637f945b6 100644
--- a/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
+++ b/drivers/net/ethernet/intel/ice/devlink/devlink_port.c
@@ -5,6 +5,9 @@
 
 #include "ice.h"
 #include "devlink.h"
+#include "devlink_port.h"
+#include "ice_lib.h"
+#include "ice_fltr.h"
 
 static int ice_active_port_option = -1;
 
@@ -428,3 +431,347 @@ void ice_devlink_destroy_vf_port(struct ice_vf *vf)
 	devl_rate_leaf_destroy(&vf->devlink_port);
 	devlink_port_unregister(&vf->devlink_port);
 }
+
+/**
+ * ice_dealloc_dynamic_port - Deallocate and remove a dynamic port
+ * @dyn_port: dynamic port instance to deallocate
+ *
+ * Free resources associated with a dynamically added devlink port. Will
+ * deactivate the port if its currently active.
+ */
+static void ice_dealloc_dynamic_port(struct ice_dynamic_port *dyn_port)
+{
+	struct devlink_port *devlink_port = &dyn_port->devlink_port;
+	struct ice_pf *pf = dyn_port->pf;
+
+	xa_erase(&pf->sf_nums, devlink_port->attrs.pci_sf.sf);
+	devl_port_unregister(devlink_port);
+	ice_vsi_free(dyn_port->vsi);
+	xa_erase(&pf->dyn_ports, dyn_port->vsi->idx);
+	kfree(dyn_port);
+}
+
+/**
+ * ice_dealloc_all_dynamic_ports - Deallocate all dynamic devlink ports
+ * @pf: pointer to the pf structure
+ */
+void ice_dealloc_all_dynamic_ports(struct ice_pf *pf)
+{
+	struct ice_dynamic_port *dyn_port;
+	unsigned long index;
+
+	xa_for_each(&pf->dyn_ports, index, dyn_port)
+		ice_dealloc_dynamic_port(dyn_port);
+}
+
+/**
+ * ice_devlink_port_new_check_attr - Check that new port attributes are valid
+ * @pf: pointer to the PF structure
+ * @new_attr: the attributes for the new port
+ * @extack: extack for reporting error messages
+ *
+ * Check that the attributes for the new port are valid before continuing to
+ * allocate the devlink port.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_devlink_port_new_check_attr(struct ice_pf *pf,
+				const struct devlink_port_new_attrs *new_attr,
+				struct netlink_ext_ack *extack)
+{
+	if (new_attr->flavour != DEVLINK_PORT_FLAVOUR_PCI_SF) {
+		NL_SET_ERR_MSG_MOD(extack, "Flavour other than pcisf is not supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (new_attr->controller_valid) {
+		NL_SET_ERR_MSG_MOD(extack, "Setting controller is not supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (new_attr->port_index_valid) {
+		NL_SET_ERR_MSG_MOD(extack, "Port index is invalid");
+		return -EOPNOTSUPP;
+	}
+
+	if (new_attr->pfnum != pf->hw.bus.func) {
+		NL_SET_ERR_MSG_MOD(extack, "Incorrect pfnum supplied");
+		return -EINVAL;
+	}
+
+	if (!pci_msix_can_alloc_dyn(pf->pdev)) {
+		NL_SET_ERR_MSG_MOD(extack, "Dynamic MSIX-X interrupt allocation is not supported");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+/**
+ * ice_devlink_port_del - devlink handler for port delete
+ * @devlink: pointer to devlink
+ * @port: devlink port to be deleted
+ * @extack: pointer to extack
+ *
+ * Deletes devlink port and deallocates all resources associated with
+ * created subfunction.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_devlink_port_del(struct devlink *devlink, struct devlink_port *port,
+		     struct netlink_ext_ack *extack)
+{
+	struct ice_dynamic_port *dyn_port;
+
+	dyn_port = ice_devlink_port_to_dyn(port);
+	ice_dealloc_dynamic_port(dyn_port);
+
+	return 0;
+}
+
+/**
+ * ice_devlink_port_fn_hw_addr_set - devlink handler for mac address set
+ * @port: pointer to devlink port
+ * @hw_addr: hw address to set
+ * @hw_addr_len: hw address length
+ * @extack: extack for reporting error messages
+ *
+ * Sets mac address for the port, verifies arguments and copies address
+ * to the subfunction structure.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_devlink_port_fn_hw_addr_set(struct devlink_port *port, const u8 *hw_addr,
+				int hw_addr_len,
+				struct netlink_ext_ack *extack)
+{
+	struct ice_dynamic_port *dyn_port;
+
+	dyn_port = ice_devlink_port_to_dyn(port);
+
+	if (hw_addr_len != ETH_ALEN || !is_valid_ether_addr(hw_addr)) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid ethernet address");
+		return -EADDRNOTAVAIL;
+	}
+
+	ether_addr_copy(dyn_port->hw_addr, hw_addr);
+
+	return 0;
+}
+
+/**
+ * ice_devlink_port_fn_hw_addr_get - devlink handler for mac address get
+ * @port: pointer to devlink port
+ * @hw_addr: hw address to set
+ * @hw_addr_len: hw address length
+ * @extack: extack for reporting error messages
+ *
+ * Returns mac address for the port.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_devlink_port_fn_hw_addr_get(struct devlink_port *port, u8 *hw_addr,
+				int *hw_addr_len,
+				struct netlink_ext_ack *extack)
+{
+	struct ice_dynamic_port *dyn_port;
+
+	dyn_port = ice_devlink_port_to_dyn(port);
+
+	ether_addr_copy(hw_addr, dyn_port->hw_addr);
+	*hw_addr_len = ETH_ALEN;
+
+	return 0;
+}
+
+static const struct devlink_port_ops ice_devlink_port_sf_ops = {
+	.port_del = ice_devlink_port_del,
+	.port_fn_hw_addr_get = ice_devlink_port_fn_hw_addr_get,
+	.port_fn_hw_addr_set = ice_devlink_port_fn_hw_addr_set,
+};
+
+/**
+ * ice_reserve_sf_num - Reserve a subfunction number for this port
+ * @pf: pointer to the pf structure
+ * @new_attr: devlink port attributes requested
+ * @extack: extack for reporting error messages
+ * @sfnum: on success, the sf number reserved
+ *
+ * Reserve a subfunction number for this port. Only called for
+ * DEVLINK_PORT_FLAVOUR_PCI_SF ports.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_reserve_sf_num(struct ice_pf *pf,
+		   const struct devlink_port_new_attrs *new_attr,
+		   struct netlink_ext_ack *extack, u32 *sfnum)
+{
+	int err;
+
+	/* If user didn't request an explicit number, pick one */
+	if (!new_attr->sfnum_valid)
+		return xa_alloc(&pf->sf_nums, sfnum, NULL, xa_limit_32b,
+				GFP_KERNEL);
+
+	/* Otherwise, check and use the number provided */
+	err = xa_insert(&pf->sf_nums, new_attr->sfnum, NULL, GFP_KERNEL);
+	if (err) {
+		if (err == -EBUSY)
+			NL_SET_ERR_MSG_MOD(extack, "Subfunction with given sfnum already exists");
+		return err;
+	}
+
+	*sfnum = new_attr->sfnum;
+
+	return 0;
+}
+
+/**
+ * ice_devlink_create_sf_port - Register PCI subfunction devlink port
+ * @dyn_port: the dynamic port instance structure for this subfunction
+ * @sfnum: the subfunction number to use for the port
+ *
+ * Register PCI subfunction flavour devlink port for a dynamically added
+ * subfunction port.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_devlink_create_sf_port(struct ice_dynamic_port *dyn_port, u32 sfnum)
+{
+	struct devlink_port_attrs attrs = {};
+	struct devlink_port *devlink_port;
+	struct devlink *devlink;
+	struct ice_vsi *vsi;
+	struct device *dev;
+	struct ice_pf *pf;
+	int err;
+
+	vsi = dyn_port->vsi;
+	pf = dyn_port->pf;
+	dev = ice_pf_to_dev(pf);
+
+	devlink_port = &dyn_port->devlink_port;
+
+	attrs.flavour = DEVLINK_PORT_FLAVOUR_PCI_SF;
+	attrs.pci_sf.pf = pf->hw.bus.func;
+	attrs.pci_sf.sf = sfnum;
+
+	devlink_port_attrs_set(devlink_port, &attrs);
+	devlink = priv_to_devlink(pf);
+
+	err = devl_port_register_with_ops(devlink, devlink_port, vsi->idx,
+					  &ice_devlink_port_sf_ops);
+	if (err) {
+		dev_err(dev, "Failed to create devlink port for Subfunction %d",
+			vsi->idx);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * ice_alloc_dynamic_port - Allocate new dynamic port
+ * @pf: pointer to the pf structure
+ * @new_attr: devlink port attributes requested
+ * @extack: extack for reporting error messages
+ * @devlink_port: index of newly created devlink port
+ *
+ * Allocate a new dynamic port instance and prepare it for configuration
+ * with devlink.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+static int
+ice_alloc_dynamic_port(struct ice_pf *pf,
+		       const struct devlink_port_new_attrs *new_attr,
+		       struct netlink_ext_ack *extack,
+		       struct devlink_port **devlink_port)
+{
+	struct ice_dynamic_port *dyn_port;
+	struct ice_vsi *vsi;
+	u32 sfnum;
+	int err;
+
+	err = ice_reserve_sf_num(pf, new_attr, extack, &sfnum);
+	if (err)
+		return err;
+
+	dyn_port = kzalloc(sizeof(*dyn_port), GFP_KERNEL);
+	if (!dyn_port) {
+		err = -ENOMEM;
+		goto unroll_reserve_sf_num;
+	}
+
+	vsi = ice_vsi_alloc(pf);
+	if (!vsi) {
+		NL_SET_ERR_MSG_MOD(extack, "Unable to allocate VSI");
+		err = -ENOMEM;
+		goto unroll_dyn_port_alloc;
+	}
+
+	dyn_port->vsi = vsi;
+	dyn_port->pf = pf;
+	eth_random_addr(dyn_port->hw_addr);
+
+	err = xa_insert(&pf->dyn_ports, vsi->idx, dyn_port, GFP_KERNEL);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Port index reservation failed");
+		goto unroll_vsi_alloc;
+	}
+
+	err = ice_devlink_create_sf_port(dyn_port, sfnum);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Port registration failed");
+		goto unroll_xa_insert;
+	}
+
+	*devlink_port = &dyn_port->devlink_port;
+
+	return 0;
+
+unroll_xa_insert:
+	xa_erase(&pf->dyn_ports, vsi->idx);
+unroll_vsi_alloc:
+	ice_vsi_free(vsi);
+unroll_dyn_port_alloc:
+	kfree(dyn_port);
+unroll_reserve_sf_num:
+	xa_erase(&pf->sf_nums, sfnum);
+
+	return err;
+}
+
+/**
+ * ice_devlink_port_new - devlink handler for the new port
+ * @devlink: pointer to devlink
+ * @new_attr: pointer to the port new attributes
+ * @extack: extack for reporting error messages
+ * @devlink_port: pointer to a new port
+ *
+ * Creates new devlink port, checks new port attributes and reject
+ * any unsupported parameters, allocates new subfunction for that port.
+ *
+ * Return: zero on success or an error code on failure.
+ */
+int
+ice_devlink_port_new(struct devlink *devlink,
+		     const struct devlink_port_new_attrs *new_attr,
+		     struct netlink_ext_ack *extack,
+		     struct devlink_port **devlink_port)
+{
+	struct ice_pf *pf = devlink_priv(devlink);
+	int err;
+
+	err = ice_devlink_port_new_check_attr(pf, new_attr, extack);
+	if (err)
+		return err;
+
+	return ice_alloc_dynamic_port(pf, new_attr, extack, devlink_port);
+}
diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink_port.h b/drivers/net/ethernet/intel/ice/devlink/devlink_port.h
index 9223bcdb6444..196db6806019 100644
--- a/drivers/net/ethernet/intel/ice/devlink/devlink_port.h
+++ b/drivers/net/ethernet/intel/ice/devlink/devlink_port.h
@@ -4,9 +4,39 @@
 #ifndef _DEVLINK_PORT_H_
 #define _DEVLINK_PORT_H_
 
+#include "../ice.h"
+
+/**
+ * struct ice_dynamic_port - Track dynamically added devlink port instance
+ * @hw_addr: the HW address for this port
+ * @active: true if the port has been activated
+ * @devlink_port: the associated devlink port structure
+ * @pf: pointer to the PF private structure
+ * @vsi: the VSI associated with this port
+ *
+ * An instance of a dynamically added devlink port. Each port flavour
+ */
+struct ice_dynamic_port {
+	u8 hw_addr[ETH_ALEN];
+	u8 active: 1;
+	struct devlink_port devlink_port;
+	struct ice_pf *pf;
+	struct ice_vsi *vsi;
+};
+
+void ice_dealloc_all_dynamic_ports(struct ice_pf *pf);
+
 int ice_devlink_create_pf_port(struct ice_pf *pf);
 void ice_devlink_destroy_pf_port(struct ice_pf *pf);
 int ice_devlink_create_vf_port(struct ice_vf *vf);
 void ice_devlink_destroy_vf_port(struct ice_vf *vf);
 
+#define ice_devlink_port_to_dyn(p) \
+	container_of(port, struct ice_dynamic_port, devlink_port)
+
+int
+ice_devlink_port_new(struct devlink *devlink,
+		     const struct devlink_port_new_attrs *new_attr,
+		     struct netlink_ext_ack *extack,
+		     struct devlink_port **devlink_port);
 #endif /* _DEVLINK_PORT_H_ */
diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index 5f7757a44b72..edc93d14464c 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -649,6 +649,9 @@ struct ice_pf {
 	struct ice_eswitch eswitch;
 	struct ice_esw_br_port *br_port;
 
+	struct xarray dyn_ports;
+	struct xarray sf_nums;
+
 #define ICE_INVALID_AGG_NODE_ID		0
 #define ICE_PF_AGG_NODE_ID_START	1
 #define ICE_MAX_PF_AGG_NODES		32
@@ -905,6 +908,7 @@ int ice_vsi_open(struct ice_vsi *vsi);
 void ice_set_ethtool_ops(struct net_device *netdev);
 void ice_set_ethtool_repr_ops(struct net_device *netdev);
 void ice_set_ethtool_safe_mode_ops(struct net_device *netdev);
+void ice_set_ethtool_sf_ops(struct net_device *netdev);
 u16 ice_get_avail_txq_count(struct ice_pf *pf);
 u16 ice_get_avail_rxq_count(struct ice_pf *pf);
 int ice_vsi_recfg_qs(struct ice_vsi *vsi, int new_rx, int new_tx, bool locked);
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index cff0bb6ba428..3e5c0651534b 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -7,6 +7,7 @@
 #include "ice_lib.h"
 #include "ice_fltr.h"
 #include "ice_dcb_lib.h"
+#include "ice_type.h"
 #include "ice_vsi_vlan_ops.h"
 
 /**
@@ -440,7 +441,7 @@ static int ice_vsi_alloc_ring_stats(struct ice_vsi *vsi)
  * This deallocates the VSI's queue resources, removes it from the PF's
  * VSI array if necessary, and deallocates the VSI
  */
-static void ice_vsi_free(struct ice_vsi *vsi)
+void ice_vsi_free(struct ice_vsi *vsi)
 {
 	struct ice_pf *pf = NULL;
 	struct device *dev;
@@ -612,7 +613,7 @@ ice_vsi_alloc_def(struct ice_vsi *vsi, struct ice_channel *ch)
  *
  * returns a pointer to a VSI on success, NULL on failure.
  */
-static struct ice_vsi *ice_vsi_alloc(struct ice_pf *pf)
+struct ice_vsi *ice_vsi_alloc(struct ice_pf *pf)
 {
 	struct device *dev = ice_pf_to_dev(pf);
 	struct ice_vsi *vsi = NULL;
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.h b/drivers/net/ethernet/intel/ice/ice_lib.h
index a57213062b7f..198cfd1fdca0 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_lib.h
@@ -103,6 +103,8 @@ void ice_dis_vsi(struct ice_vsi *vsi, bool locked);
 
 int ice_vsi_rebuild(struct ice_vsi *vsi, u32 vsi_flags);
 int ice_vsi_cfg(struct ice_vsi *vsi, struct ice_vsi_cfg_params *params);
+struct ice_vsi *ice_vsi_alloc(struct ice_pf *pf);
+void ice_vsi_free(struct ice_vsi *vsi);
 
 bool ice_is_reset_in_progress(unsigned long *state);
 int ice_wait_for_reset(struct ice_pf *pf, unsigned long timeout);
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 058d2a8836b0..9bbb7b328ae9 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -3964,6 +3964,9 @@ static void ice_deinit_pf(struct ice_pf *pf)
 
 	if (pf->ptp.clock)
 		ptp_clock_unregister(pf->ptp.clock);
+
+	xa_destroy(&pf->dyn_ports);
+	xa_destroy(&pf->sf_nums);
 }
 
 /**
@@ -4057,6 +4060,9 @@ static int ice_init_pf(struct ice_pf *pf)
 	hash_init(pf->vfs.table);
 	ice_mbx_init_snapshot(&pf->hw);
 
+	xa_init(&pf->dyn_ports);
+	xa_init(&pf->sf_nums);
+
 	return 0;
 }
 
@@ -5376,6 +5382,7 @@ static void ice_remove(struct pci_dev *pdev)
 		ice_remove_arfs(pf);
 
 	devl_lock(priv_to_devlink(pf));
+	ice_dealloc_all_dynamic_ports(pf);
 	ice_deinit_devlink(pf);
 
 	ice_unload(pf);
@@ -6670,7 +6677,7 @@ static int ice_up_complete(struct ice_vsi *vsi)
 
 	if (vsi->port_info &&
 	    (vsi->port_info->phy.link_info.link_info & ICE_AQ_LINK_UP) &&
-	    vsi->netdev && vsi->type == ICE_VSI_PF) {
+	    ((vsi->netdev && vsi->type == ICE_VSI_PF))) {
 		ice_print_link_msg(vsi, true);
 		netif_tx_start_all_queues(vsi->netdev);
 		netif_carrier_on(vsi->netdev);
-- 
2.42.0


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