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>

1 files changed, 280 insertions, 30 deletions

diff --git a/net/core/devlink.c b/net/core/devlink.c
index f6e6445b9801..737b61c2976e 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -87,6 +87,9 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(devlink_trap_report);
 
 static const struct nla_policy devlink_function_nl_policy[DEVLINK_PORT_FUNCTION_ATTR_MAX + 1] = {
 	[DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR] = { .type = NLA_BINARY },
+	[DEVLINK_PORT_FN_ATTR_STATE] =
+		NLA_POLICY_RANGE(NLA_U8, DEVLINK_PORT_FN_STATE_INACTIVE,
+				 DEVLINK_PORT_FN_STATE_ACTIVE),
 };
 
 static LIST_HEAD(devlink_list);
@@ -690,6 +693,15 @@ static int devlink_nl_port_attrs_put(struct sk_buff *msg,
 		if (nla_put_u8(msg, DEVLINK_ATTR_PORT_EXTERNAL, attrs->pci_vf.external))
 			return -EMSGSIZE;
 		break;
+	case DEVLINK_PORT_FLAVOUR_PCI_SF:
+		if (nla_put_u32(msg, DEVLINK_ATTR_PORT_CONTROLLER_NUMBER,
+				attrs->pci_sf.controller) ||
+		    nla_put_u16(msg, DEVLINK_ATTR_PORT_PCI_PF_NUMBER,
+				attrs->pci_sf.pf) ||
+		    nla_put_u32(msg, DEVLINK_ATTR_PORT_PCI_SF_NUMBER,
+				attrs->pci_sf.sf))
+			return -EMSGSIZE;
+		break;
 	case DEVLINK_PORT_FLAVOUR_PHYSICAL:
 	case DEVLINK_PORT_FLAVOUR_CPU:
 	case DEVLINK_PORT_FLAVOUR_DSA:
@@ -713,42 +725,105 @@ static int devlink_nl_port_attrs_put(struct sk_buff *msg,
 }
 
 static int
+devlink_port_fn_hw_addr_fill(struct devlink *devlink, const struct devlink_ops *ops,
+			     struct devlink_port *port, struct sk_buff *msg,
+			     struct netlink_ext_ack *extack, bool *msg_updated)
+{
+	u8 hw_addr[MAX_ADDR_LEN];
+	int hw_addr_len;
+	int err;
+
+	if (!ops->port_function_hw_addr_get)
+		return 0;
+
+	err = ops->port_function_hw_addr_get(devlink, port, hw_addr, &hw_addr_len, extack);
+	if (err) {
+		if (err == -EOPNOTSUPP)
+			return 0;
+		return err;
+	}
+	err = nla_put(msg, DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR, hw_addr_len, hw_addr);
+	if (err)
+		return err;
+	*msg_updated = true;
+	return 0;
+}
+
+static bool
+devlink_port_fn_state_valid(enum devlink_port_fn_state state)
+{
+	return state == DEVLINK_PORT_FN_STATE_INACTIVE ||
+	       state == DEVLINK_PORT_FN_STATE_ACTIVE;
+}
+
+static bool
+devlink_port_fn_opstate_valid(enum devlink_port_fn_opstate opstate)
+{
+	return opstate == DEVLINK_PORT_FN_OPSTATE_DETACHED ||
+	       opstate == DEVLINK_PORT_FN_OPSTATE_ATTACHED;
+}
+
+static int
+devlink_port_fn_state_fill(struct devlink *devlink,
+			   const struct devlink_ops *ops,
+			   struct devlink_port *port, struct sk_buff *msg,
+			   struct netlink_ext_ack *extack,
+			   bool *msg_updated)
+{
+	enum devlink_port_fn_opstate opstate;
+	enum devlink_port_fn_state state;
+	int err;
+
+	if (!ops->port_fn_state_get)
+		return 0;
+
+	err = ops->port_fn_state_get(devlink, port, &state, &opstate, extack);
+	if (err) {
+		if (err == -EOPNOTSUPP)
+			return 0;
+		return err;
+	}
+	if (!devlink_port_fn_state_valid(state)) {
+		WARN_ON_ONCE(1);
+		NL_SET_ERR_MSG_MOD(extack, "Invalid state read from driver");
+		return -EINVAL;
+	}
+	if (!devlink_port_fn_opstate_valid(opstate)) {
+		WARN_ON_ONCE(1);
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Invalid operational state read from driver");
+		return -EINVAL;
+	}
+	if (nla_put_u8(msg, DEVLINK_PORT_FN_ATTR_STATE, state) ||
+	    nla_put_u8(msg, DEVLINK_PORT_FN_ATTR_OPSTATE, opstate))
+		return -EMSGSIZE;
+	*msg_updated = true;
+	return 0;
+}
+
+static int
 devlink_nl_port_function_attrs_put(struct sk_buff *msg, struct devlink_port *port,
 				   struct netlink_ext_ack *extack)
 {
 	struct devlink *devlink = port->devlink;
 	const struct devlink_ops *ops;
 	struct nlattr *function_attr;
-	bool empty_nest = true;
-	int err = 0;
+	bool msg_updated = false;
+	int err;
 
 	function_attr = nla_nest_start_noflag(msg, DEVLINK_ATTR_PORT_FUNCTION);
 	if (!function_attr)
 		return -EMSGSIZE;
 
 	ops = devlink->ops;
-	if (ops->port_function_hw_addr_get) {
-		int hw_addr_len;
-		u8 hw_addr[MAX_ADDR_LEN];
-
-		err = ops->port_function_hw_addr_get(devlink, port, hw_addr, &hw_addr_len, extack);
-		if (err == -EOPNOTSUPP) {
-			/* Port function attributes are optional for a port. If port doesn't
-			 * support function attribute, returning -EOPNOTSUPP is not an error.
-			 */
-			err = 0;
-			goto out;
-		} else if (err) {
-			goto out;
-		}
-		err = nla_put(msg, DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR, hw_addr_len, hw_addr);
-		if (err)
-			goto out;
-		empty_nest = false;
-	}
-
+	err = devlink_port_fn_hw_addr_fill(devlink, ops, port, msg,
+					   extack, &msg_updated);
+	if (err)
+		goto out;
+	err = devlink_port_fn_state_fill(devlink, ops, port, msg, extack,
+					 &msg_updated);
 out:
-	if (err || empty_nest)
+	if (err || !msg_updated)
 		nla_nest_cancel(msg, function_attr);
 	else
 		nla_nest_end(msg, function_attr);
@@ -986,7 +1061,6 @@ devlink_port_function_hw_addr_set(struct devlink *devlink, struct devlink_port *
 	const struct devlink_ops *ops;
 	const u8 *hw_addr;
 	int hw_addr_len;
-	int err;
 
 	hw_addr = nla_data(attr);
 	hw_addr_len = nla_len(attr);
@@ -1011,12 +1085,25 @@ devlink_port_function_hw_addr_set(struct devlink *devlink, struct devlink_port *
 		return -EOPNOTSUPP;
 	}
 
-	err = ops->port_function_hw_addr_set(devlink, port, hw_addr, hw_addr_len, extack);
-	if (err)
-		return err;
+	return ops->port_function_hw_addr_set(devlink, port, hw_addr, hw_addr_len, extack);
+}
 
-	devlink_port_notify(port, DEVLINK_CMD_PORT_NEW);
-	return 0;
+static int devlink_port_fn_state_set(struct devlink *devlink,
+				     struct devlink_port *port,
+				     const struct nlattr *attr,
+				     struct netlink_ext_ack *extack)
+{
+	enum devlink_port_fn_state state;
+	const struct devlink_ops *ops;
+
+	state = nla_get_u8(attr);
+	ops = devlink->ops;
+	if (!ops->port_fn_state_set) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Function does not support state setting");
+		return -EOPNOTSUPP;
+	}
+	return ops->port_fn_state_set(devlink, port, state, extack);
 }
 
 static int
@@ -1034,9 +1121,21 @@ devlink_port_function_set(struct devlink *devlink, struct devlink_port *port,
 	}
 
 	attr = tb[DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR];
-	if (attr)
+	if (attr) {
 		err = devlink_port_function_hw_addr_set(devlink, port, attr, extack);
+		if (err)
+			return err;
+	}
+	/* Keep this as the last function attribute set, so that when
+	 * multiple port function attributes are set along with state,
+	 * Those can be applied first before activating the state.
+	 */
+	attr = tb[DEVLINK_PORT_FN_ATTR_STATE];
+	if (attr)
+		err = devlink_port_fn_state_set(devlink, port, attr, extack);
 
+	if (!err)
+		devlink_port_notify(port, DEVLINK_CMD_PORT_NEW);
 	return err;
 }
 
@@ -1136,6 +1235,111 @@ static int devlink_nl_cmd_port_unsplit_doit(struct sk_buff *skb,
 	return devlink_port_unsplit(devlink, port_index, info->extack);
 }
 
+static int devlink_port_new_notifiy(struct devlink *devlink,
+				    unsigned int port_index,
+				    struct genl_info *info)
+{
+	struct devlink_port *devlink_port;
+	struct sk_buff *msg;
+	int err;
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	mutex_lock(&devlink->lock);
+	devlink_port = devlink_port_get_by_index(devlink, port_index);
+	if (!devlink_port) {
+		err = -ENODEV;
+		goto out;
+	}
+
+	err = devlink_nl_port_fill(msg, devlink, devlink_port,
+				   DEVLINK_CMD_NEW, info->snd_portid,
+				   info->snd_seq, 0, NULL);
+	if (err)
+		goto out;
+
+	err = genlmsg_reply(msg, info);
+	mutex_unlock(&devlink->lock);
+	return err;
+
+out:
+	mutex_unlock(&devlink->lock);
+	nlmsg_free(msg);
+	return err;
+}
+
+static int devlink_nl_cmd_port_new_doit(struct sk_buff *skb,
+					struct genl_info *info)
+{
+	struct netlink_ext_ack *extack = info->extack;
+	struct devlink_port_new_attrs new_attrs = {};
+	struct devlink *devlink = info->user_ptr[0];
+	unsigned int new_port_index;
+	int err;
+
+	if (!devlink->ops->port_new || !devlink->ops->port_del)
+		return -EOPNOTSUPP;
+
+	if (!info->attrs[DEVLINK_ATTR_PORT_FLAVOUR] ||
+	    !info->attrs[DEVLINK_ATTR_PORT_PCI_PF_NUMBER]) {
+		NL_SET_ERR_MSG_MOD(extack, "Port flavour or PCI PF are not specified");
+		return -EINVAL;
+	}
+	new_attrs.flavour = nla_get_u16(info->attrs[DEVLINK_ATTR_PORT_FLAVOUR]);
+	new_attrs.pfnum =
+		nla_get_u16(info->attrs[DEVLINK_ATTR_PORT_PCI_PF_NUMBER]);
+
+	if (info->attrs[DEVLINK_ATTR_PORT_INDEX]) {
+		/* Port index of the new port being created by driver. */
+		new_attrs.port_index =
+			nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_INDEX]);
+		new_attrs.port_index_valid = true;
+	}
+	if (info->attrs[DEVLINK_ATTR_PORT_CONTROLLER_NUMBER]) {
+		new_attrs.controller =
+			nla_get_u16(info->attrs[DEVLINK_ATTR_PORT_CONTROLLER_NUMBER]);
+		new_attrs.controller_valid = true;
+	}
+	if (new_attrs.flavour == DEVLINK_PORT_FLAVOUR_PCI_SF &&
+	    info->attrs[DEVLINK_ATTR_PORT_PCI_SF_NUMBER]) {
+		new_attrs.sfnum = nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_PCI_SF_NUMBER]);
+		new_attrs.sfnum_valid = true;
+	}
+
+	err = devlink->ops->port_new(devlink, &new_attrs, extack,
+				     &new_port_index);
+	if (err)
+		return err;
+
+	err = devlink_port_new_notifiy(devlink, new_port_index, info);
+	if (err && err != -ENODEV) {
+		/* Fail to send the response; destroy newly created port. */
+		devlink->ops->port_del(devlink, new_port_index, extack);
+	}
+	return err;
+}
+
+static int devlink_nl_cmd_port_del_doit(struct sk_buff *skb,
+					struct genl_info *info)
+{
+	struct netlink_ext_ack *extack = info->extack;
+	struct devlink *devlink = info->user_ptr[0];
+	unsigned int port_index;
+
+	if (!devlink->ops->port_del)
+		return -EOPNOTSUPP;
+
+	if (!info->attrs[DEVLINK_ATTR_PORT_INDEX]) {
+		NL_SET_ERR_MSG_MOD(extack, "Port index is not specified");
+		return -EINVAL;
+	}
+	port_index = nla_get_u32(info->attrs[DEVLINK_ATTR_PORT_INDEX]);
+
+	return devlink->ops->port_del(devlink, port_index, extack);
+}
+
 static int devlink_nl_sb_fill(struct sk_buff *msg, struct devlink *devlink,
 			      struct devlink_sb *devlink_sb,
 			      enum devlink_command cmd, u32 portid,
@@ -7594,6 +7798,10 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_RELOAD_ACTION] = NLA_POLICY_RANGE(NLA_U8, DEVLINK_RELOAD_ACTION_DRIVER_REINIT,
 							DEVLINK_RELOAD_ACTION_MAX),
 	[DEVLINK_ATTR_RELOAD_LIMITS] = NLA_POLICY_BITFIELD32(DEVLINK_RELOAD_LIMITS_VALID_MASK),
+	[DEVLINK_ATTR_PORT_FLAVOUR] = { .type = NLA_U16 },
+	[DEVLINK_ATTR_PORT_PCI_PF_NUMBER] = { .type = NLA_U16 },
+	[DEVLINK_ATTR_PORT_PCI_SF_NUMBER] = { .type = NLA_U32 },
+	[DEVLINK_ATTR_PORT_CONTROLLER_NUMBER] = { .type = NLA_U32 },
 };
 
 static const struct genl_small_ops devlink_nl_ops[] = {
@@ -7634,6 +7842,18 @@ static const struct genl_small_ops devlink_nl_ops[] = {
 		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
+		.cmd = DEVLINK_CMD_PORT_NEW,
+		.doit = devlink_nl_cmd_port_new_doit,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
+	},
+	{
+		.cmd = DEVLINK_CMD_PORT_DEL,
+		.doit = devlink_nl_cmd_port_del_doit,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
+	},
+	{
 		.cmd = DEVLINK_CMD_SB_GET,
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
 		.doit = devlink_nl_cmd_sb_get_doit,
@@ -8372,6 +8592,32 @@ void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port, u32 contro
 }
 EXPORT_SYMBOL_GPL(devlink_port_attrs_pci_vf_set);
 
+/**
+ *	devlink_port_attrs_pci_sf_set - Set PCI SF port attributes
+ *
+ *	@devlink_port: devlink port
+ *	@controller: associated controller number for the devlink port instance
+ *	@pf: associated PF for the devlink port instance
+ *	@sf: associated SF of a PF for the devlink port instance
+ */
+void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port, u32 controller,
+				   u16 pf, u32 sf)
+{
+	struct devlink_port_attrs *attrs = &devlink_port->attrs;
+	int ret;
+
+	if (WARN_ON(devlink_port->registered))
+		return;
+	ret = __devlink_port_attrs_set(devlink_port,
+				       DEVLINK_PORT_FLAVOUR_PCI_SF);
+	if (ret)
+		return;
+	attrs->pci_sf.controller = controller;
+	attrs->pci_sf.pf = pf;
+	attrs->pci_sf.sf = sf;
+}
+EXPORT_SYMBOL_GPL(devlink_port_attrs_pci_sf_set);
+
 static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
 					     char *name, size_t len)
 {
@@ -8420,6 +8666,10 @@ static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
 		n = snprintf(name, len, "pf%uvf%u",
 			     attrs->pci_vf.pf, attrs->pci_vf.vf);
 		break;
+	case DEVLINK_PORT_FLAVOUR_PCI_SF:
+		n = snprintf(name, len, "pf%usf%u", attrs->pci_sf.pf,
+			     attrs->pci_sf.sf);
+		break;
 	}
 
 	if (n >= len)