[patch net-next RFC 02/10] devlink: implement line card provisioning

[Jiri Pirko <jiri@resnulli.us>]

From: Jiri Pirko <jiri@nvidia.com>

In order to be able to configure all needed stuff on a port/netdevice
of a line card without the line card being present, introduce line card
provisioning. Basically provisioning will create a placeholder for
instances (ports/netdevices) for a line card type.

Allow the user to query the supported line card types over line card
get command. Then implement two netlink commands to allow user to
provision/unprovision the line card with selected line card type.

On the driver API side, add provision/unprovision ops and supported
types array to be advertised. Upon provision op call, the driver should
take care of creating the instances for the particular line card type.
Introduce provision_set/clear() functions to be called by the driver
once the provisioning/unprovisioning is done on its side.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
---
 include/net/devlink.h        |  31 +++++++-
 include/uapi/linux/devlink.h |  17 +++++
 net/core/devlink.c           | 141 ++++++++++++++++++++++++++++++++++-
 3 files changed, 185 insertions(+), 4 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 67c2547d5ef9..854abd53e9ea 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -139,10 +139,33 @@ struct devlink_port {
 	struct mutex reporters_lock; /* Protects reporter_list */
 };
 
+struct devlink_linecard_ops;
+
 struct devlink_linecard {
 	struct list_head list;
 	struct devlink *devlink;
 	unsigned int index;
+	const struct devlink_linecard_ops *ops;
+	void *priv;
+	enum devlink_linecard_state state;
+	const char *provisioned_type;
+};
+
+/**
+ * struct devlink_linecard_ops - Linecard operations
+ * @supported_types: array of supported types of linecards
+ * @supported_types_count: number of elements in the array above
+ * @provision: callback to provision the linecard slot with certain
+ *	       type of linecard
+ * @unprovision: callback to unprovision the linecard slot
+ */
+struct devlink_linecard_ops {
+	const char **supported_types;
+	unsigned int supported_types_count;
+	int (*provision)(struct devlink_linecard *linecard, void *priv,
+			 u32 type_index, struct netlink_ext_ack *extack);
+	int (*unprovision)(struct devlink_linecard *linecard, void *priv,
+			   struct netlink_ext_ack *extack);
 };
 
 struct devlink_sb_pool_info {
@@ -1414,9 +1437,13 @@ 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);
-struct devlink_linecard *devlink_linecard_create(struct devlink *devlink,
-						 unsigned int linecard_index);
+struct devlink_linecard *
+devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
+			const struct devlink_linecard_ops *ops, void *priv);
 void devlink_linecard_destroy(struct devlink_linecard *linecard);
+void devlink_linecard_provision_set(struct devlink_linecard *linecard,
+				    u32 type_index);
+void devlink_linecard_provision_clear(struct devlink_linecard *linecard);
 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 e5ed0522591f..4111ddcc000b 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -131,6 +131,9 @@ enum devlink_command {
 	DEVLINK_CMD_LINECARD_NEW,
 	DEVLINK_CMD_LINECARD_DEL,
 
+	DEVLINK_CMD_LINECARD_PROVISION,
+	DEVLINK_CMD_LINECARD_UNPROVISION,
+
 	/* add new commands above here */
 	__DEVLINK_CMD_MAX,
 	DEVLINK_CMD_MAX = __DEVLINK_CMD_MAX - 1
@@ -329,6 +332,17 @@ enum devlink_reload_limit {
 
 #define DEVLINK_RELOAD_LIMITS_VALID_MASK (_BITUL(__DEVLINK_RELOAD_LIMIT_MAX) - 1)
 
+enum devlink_linecard_state {
+	DEVLINK_LINECARD_STATE_UNSPEC,
+	DEVLINK_LINECARD_STATE_UNPROVISIONED,
+	DEVLINK_LINECARD_STATE_UNPROVISIONING,
+	DEVLINK_LINECARD_STATE_PROVISIONING,
+	DEVLINK_LINECARD_STATE_PROVISIONED,
+
+	__DEVLINK_LINECARD_STATE_MAX,
+	DEVLINK_LINECARD_STATE_MAX = __DEVLINK_LINECARD_STATE_MAX - 1
+};
+
 enum devlink_attr {
 	/* don't change the order or add anything between, this is ABI! */
 	DEVLINK_ATTR_UNSPEC,
@@ -535,6 +549,9 @@ enum devlink_attr {
 	DEVLINK_ATTR_RELOAD_ACTION_STATS,       /* nested */
 
 	DEVLINK_ATTR_LINECARD_INDEX,		/* u32 */
+	DEVLINK_ATTR_LINECARD_STATE,		/* u8 */
+	DEVLINK_ATTR_LINECARD_TYPE,		/* string */
+	DEVLINK_ATTR_LINECARD_SUPPORTED_TYPES,	/* nested */
 
 	/* add new attributes above here, update the policy in devlink.c */
 
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 564e921133cf..434eecc310c3 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -1192,7 +1192,9 @@ static int devlink_nl_linecard_fill(struct sk_buff *msg,
 				    u32 seq, int flags,
 				    struct netlink_ext_ack *extack)
 {
+	struct nlattr *attr;
 	void *hdr;
+	int i;
 
 	hdr = genlmsg_put(msg, portid, seq, &devlink_nl_family, flags, cmd);
 	if (!hdr)
@@ -1202,6 +1204,22 @@ static int devlink_nl_linecard_fill(struct sk_buff *msg,
 		goto nla_put_failure;
 	if (nla_put_u32(msg, DEVLINK_ATTR_LINECARD_INDEX, linecard->index))
 		goto nla_put_failure;
+	if (nla_put_u8(msg, DEVLINK_ATTR_LINECARD_STATE, linecard->state))
+		goto nla_put_failure;
+	if (linecard->state >= DEVLINK_LINECARD_STATE_PROVISIONED &&
+	    nla_put_string(msg, DEVLINK_ATTR_LINECARD_TYPE,
+			   linecard->provisioned_type))
+		goto nla_put_failure;
+
+	attr = nla_nest_start(msg, DEVLINK_ATTR_LINECARD_SUPPORTED_TYPES);
+	if (!attr)
+		return -EMSGSIZE;
+	for (i = 0; i < linecard->ops->supported_types_count; i++) {
+		if (nla_put_string(msg, DEVLINK_ATTR_LINECARD_TYPE,
+				   linecard->ops->supported_types[i]))
+			goto nla_put_failure;
+	}
+	nla_nest_end(msg, attr);
 
 	genlmsg_end(msg, hdr);
 	return 0;
@@ -1300,6 +1318,68 @@ static int devlink_nl_cmd_linecard_get_dumpit(struct sk_buff *msg,
 	return msg->len;
 }
 
+static int devlink_nl_cmd_linecard_provision_doit(struct sk_buff *skb,
+						  struct genl_info *info)
+{
+	struct devlink_linecard *linecard = info->user_ptr[1];
+	const char *type;
+	int i;
+
+	if (linecard->state == DEVLINK_LINECARD_STATE_PROVISIONING) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard is currently being provisioned");
+		return -EBUSY;
+	}
+	if (linecard->state == DEVLINK_LINECARD_STATE_UNPROVISIONING) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard is currently being unprovisioned");
+		return -EBUSY;
+	}
+	if (linecard->state != DEVLINK_LINECARD_STATE_UNPROVISIONED) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard already provisioned");
+		return -EBUSY;
+	}
+
+	if (!info->attrs[DEVLINK_ATTR_LINECARD_TYPE]) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Provision type not provided");
+		return -EINVAL;
+	}
+
+	type = nla_data(info->attrs[DEVLINK_ATTR_LINECARD_TYPE]);
+	for (i = 0; i < linecard->ops->supported_types_count; i++) {
+		if (!strcmp(linecard->ops->supported_types[i], type)) {
+			linecard->state = DEVLINK_LINECARD_STATE_PROVISIONING;
+			devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
+			return linecard->ops->provision(linecard,
+							linecard->priv, i,
+							info->extack);
+		}
+	}
+	NL_SET_ERR_MSG_MOD(info->extack, "Unsupported provision type provided");
+	return -EINVAL;
+}
+
+static int devlink_nl_cmd_linecard_unprovision_doit(struct sk_buff *skb,
+						    struct genl_info *info)
+{
+	struct devlink_linecard *linecard = info->user_ptr[1];
+
+	if (linecard->state == DEVLINK_LINECARD_STATE_PROVISIONING) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard is currently being provisioned");
+		return -EBUSY;
+	}
+	if (linecard->state == DEVLINK_LINECARD_STATE_UNPROVISIONING) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard is currently being unprovisioned");
+		return -EBUSY;
+	}
+	if (linecard->state == DEVLINK_LINECARD_STATE_UNPROVISIONED) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Linecard is not provisioned");
+		return -EOPNOTSUPP;
+	}
+	linecard->state = DEVLINK_LINECARD_STATE_UNPROVISIONING;
+	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
+	return linecard->ops->unprovision(linecard, linecard->priv,
+					  info->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,
@@ -7759,6 +7839,7 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 							DEVLINK_RELOAD_ACTION_MAX),
 	[DEVLINK_ATTR_RELOAD_LIMITS] = NLA_POLICY_BITFIELD32(DEVLINK_RELOAD_LIMITS_VALID_MASK),
 	[DEVLINK_ATTR_LINECARD_INDEX] = { .type = NLA_U32 },
+	[DEVLINK_ATTR_LINECARD_TYPE] = { .type = NLA_NUL_STRING },
 };
 
 static const struct genl_small_ops devlink_nl_ops[] = {
@@ -7806,6 +7887,20 @@ static const struct genl_small_ops devlink_nl_ops[] = {
 		.internal_flags = DEVLINK_NL_FLAG_NEED_LINECARD,
 		/* can be retrieved by unprivileged users */
 	},
+	{
+		.cmd = DEVLINK_CMD_LINECARD_PROVISION,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.doit = devlink_nl_cmd_linecard_provision_doit,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = DEVLINK_NL_FLAG_NEED_LINECARD,
+	},
+	{
+		.cmd = DEVLINK_CMD_LINECARD_UNPROVISION,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.doit = devlink_nl_cmd_linecard_unprovision_doit,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = DEVLINK_NL_FLAG_NEED_LINECARD,
+	},
 	{
 		.cmd = DEVLINK_CMD_SB_GET,
 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
@@ -8613,11 +8708,17 @@ static int __devlink_port_phys_port_name_get(struct devlink_port *devlink_port,
  *	Create devlink linecard instance with provided linecard index.
  *	Caller can use any indexing, even hw-related one.
  */
-struct devlink_linecard *devlink_linecard_create(struct devlink *devlink,
-						 unsigned int linecard_index)
+struct devlink_linecard *
+devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
+			const struct devlink_linecard_ops *ops, void *priv)
 {
 	struct devlink_linecard *linecard;
 
+	if (WARN_ON(!ops || !ops->supported_types ||
+		    !ops->supported_types_count ||
+		    !ops->provision || !ops->unprovision))
+		return ERR_PTR(-EINVAL);
+
 	mutex_lock(&devlink->lock);
 	if (devlink_linecard_index_exists(devlink, linecard_index)) {
 		mutex_unlock(&devlink->lock);
@@ -8630,6 +8731,9 @@ struct devlink_linecard *devlink_linecard_create(struct devlink *devlink,
 
 	linecard->devlink = devlink;
 	linecard->index = linecard_index;
+	linecard->ops = ops;
+	linecard->priv = priv;
+	linecard->state = DEVLINK_LINECARD_STATE_UNPROVISIONED;
 	list_add_tail(&linecard->list, &devlink->linecard_list);
 	mutex_unlock(&devlink->lock);
 	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
@@ -8653,6 +8757,39 @@ void devlink_linecard_destroy(struct devlink_linecard *linecard)
 }
 EXPORT_SYMBOL_GPL(devlink_linecard_create);
 
+/**
+ *	devlink_linecard_provision_set - Set provisioning on linecard
+ *
+ *	@devlink_linecard: devlink linecard
+ *	@type_index: index of the linecard type (in array of types in ops)
+ */
+void devlink_linecard_provision_set(struct devlink_linecard *linecard,
+				    u32 type_index)
+{
+	WARN_ON(type_index >= linecard->ops->supported_types_count);
+	mutex_lock(&linecard->devlink->lock);
+	linecard->state = DEVLINK_LINECARD_STATE_PROVISIONED;
+	linecard->provisioned_type = linecard->ops->supported_types[type_index];
+	mutex_unlock(&linecard->devlink->lock);
+	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
+}
+EXPORT_SYMBOL_GPL(devlink_linecard_provision_set);
+
+/**
+ *	devlink_linecard_provision_clear - Clear provisioning on linecard
+ *
+ *	@devlink_linecard: devlink linecard
+ */
+void devlink_linecard_provision_clear(struct devlink_linecard *linecard)
+{
+	mutex_lock(&linecard->devlink->lock);
+	linecard->state = DEVLINK_LINECARD_STATE_UNPROVISIONED;
+	linecard->provisioned_type = NULL;
+	mutex_unlock(&linecard->devlink->lock);
+	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
+}
+EXPORT_SYMBOL_GPL(devlink_linecard_provision_clear);
+
 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,
-- 
2.26.2