Merge branch 'devlink-Add-configuration-parameters-support'

Moshe Shemesh says:

====================
Add configuration parameters support

Add configuration parameters setting through devlink.
Each device registers supported configuration parameters table.
Each parameter can be either generic or driver specific.
The user can retrieve data on these parameters by "devlink param show"
command and can set new value to a parameter by "devlink param set"
command.
The parameters can be set in different configuration modes:
  runtime - set while driver is running, no reset required.
  driverinit - applied while driver initializes, requires restart
               driver by devlink reload command.
  permanent - written to device's non-volatile memory, hard reset required.

The patches at the end of the patchset introduce few params that are using
the introduced infrastructure on mlx4 and bnxt.

Command examples and output:

pci/0000:81:00.0:
  name internal_error_reset type generic
    values:
      cmode runtime value true
      cmode driverinit value true
  name max_macs type generic
    values:
      cmode driverinit value 128
  name enable_64b_cqe_eqe type driver-specific
    values:
      cmode driverinit value true
  name enable_4k_uar type driver-specific
    values:
      cmode driverinit value false

pci/0000:81:00.0:
  name internal_error_reset type generic
    values:
      cmode runtime value false
      cmode driverinit value true
====================

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

1 files changed, 675 insertions, 0 deletions

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 22099705cc41..470f3dbfecfe 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -2604,6 +2604,500 @@ static int devlink_nl_cmd_reload(struct sk_buff *skb, struct genl_info *info)
 	return devlink->ops->reload(devlink, info->extack);
 }
 
+static const struct devlink_param devlink_param_generic[] = {
+	{
+		.id = DEVLINK_PARAM_GENERIC_ID_INT_ERR_RESET,
+		.name = DEVLINK_PARAM_GENERIC_INT_ERR_RESET_NAME,
+		.type = DEVLINK_PARAM_GENERIC_INT_ERR_RESET_TYPE,
+	},
+	{
+		.id = DEVLINK_PARAM_GENERIC_ID_MAX_MACS,
+		.name = DEVLINK_PARAM_GENERIC_MAX_MACS_NAME,
+		.type = DEVLINK_PARAM_GENERIC_MAX_MACS_TYPE,
+	},
+	{
+		.id = DEVLINK_PARAM_GENERIC_ID_ENABLE_SRIOV,
+		.name = DEVLINK_PARAM_GENERIC_ENABLE_SRIOV_NAME,
+		.type = DEVLINK_PARAM_GENERIC_ENABLE_SRIOV_TYPE,
+	},
+};
+
+static int devlink_param_generic_verify(const struct devlink_param *param)
+{
+	/* verify it match generic parameter by id and name */
+	if (param->id > DEVLINK_PARAM_GENERIC_ID_MAX)
+		return -EINVAL;
+	if (strcmp(param->name, devlink_param_generic[param->id].name))
+		return -ENOENT;
+
+	WARN_ON(param->type != devlink_param_generic[param->id].type);
+
+	return 0;
+}
+
+static int devlink_param_driver_verify(const struct devlink_param *param)
+{
+	int i;
+
+	if (param->id <= DEVLINK_PARAM_GENERIC_ID_MAX)
+		return -EINVAL;
+	/* verify no such name in generic params */
+	for (i = 0; i <= DEVLINK_PARAM_GENERIC_ID_MAX; i++)
+		if (!strcmp(param->name, devlink_param_generic[i].name))
+			return -EEXIST;
+
+	return 0;
+}
+
+static struct devlink_param_item *
+devlink_param_find_by_name(struct list_head *param_list,
+			   const char *param_name)
+{
+	struct devlink_param_item *param_item;
+
+	list_for_each_entry(param_item, param_list, list)
+		if (!strcmp(param_item->param->name, param_name))
+			return param_item;
+	return NULL;
+}
+
+static struct devlink_param_item *
+devlink_param_find_by_id(struct list_head *param_list, u32 param_id)
+{
+	struct devlink_param_item *param_item;
+
+	list_for_each_entry(param_item, param_list, list)
+		if (param_item->param->id == param_id)
+			return param_item;
+	return NULL;
+}
+
+static bool
+devlink_param_cmode_is_supported(const struct devlink_param *param,
+				 enum devlink_param_cmode cmode)
+{
+	return test_bit(cmode, &param->supported_cmodes);
+}
+
+static int devlink_param_get(struct devlink *devlink,
+			     const struct devlink_param *param,
+			     struct devlink_param_gset_ctx *ctx)
+{
+	if (!param->get)
+		return -EOPNOTSUPP;
+	return param->get(devlink, param->id, ctx);
+}
+
+static int devlink_param_set(struct devlink *devlink,
+			     const struct devlink_param *param,
+			     struct devlink_param_gset_ctx *ctx)
+{
+	if (!param->set)
+		return -EOPNOTSUPP;
+	return param->set(devlink, param->id, ctx);
+}
+
+static int
+devlink_param_type_to_nla_type(enum devlink_param_type param_type)
+{
+	switch (param_type) {
+	case DEVLINK_PARAM_TYPE_U8:
+		return NLA_U8;
+	case DEVLINK_PARAM_TYPE_U16:
+		return NLA_U16;
+	case DEVLINK_PARAM_TYPE_U32:
+		return NLA_U32;
+	case DEVLINK_PARAM_TYPE_STRING:
+		return NLA_STRING;
+	case DEVLINK_PARAM_TYPE_BOOL:
+		return NLA_FLAG;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int
+devlink_nl_param_value_fill_one(struct sk_buff *msg,
+				enum devlink_param_type type,
+				enum devlink_param_cmode cmode,
+				union devlink_param_value val)
+{
+	struct nlattr *param_value_attr;
+
+	param_value_attr = nla_nest_start(msg, DEVLINK_ATTR_PARAM_VALUE);
+	if (!param_value_attr)
+		goto nla_put_failure;
+
+	if (nla_put_u8(msg, DEVLINK_ATTR_PARAM_VALUE_CMODE, cmode))
+		goto value_nest_cancel;
+
+	switch (type) {
+	case DEVLINK_PARAM_TYPE_U8:
+		if (nla_put_u8(msg, DEVLINK_ATTR_PARAM_VALUE_DATA, val.vu8))
+			goto value_nest_cancel;
+		break;
+	case DEVLINK_PARAM_TYPE_U16:
+		if (nla_put_u16(msg, DEVLINK_ATTR_PARAM_VALUE_DATA, val.vu16))
+			goto value_nest_cancel;
+		break;
+	case DEVLINK_PARAM_TYPE_U32:
+		if (nla_put_u32(msg, DEVLINK_ATTR_PARAM_VALUE_DATA, val.vu32))
+			goto value_nest_cancel;
+		break;
+	case DEVLINK_PARAM_TYPE_STRING:
+		if (nla_put_string(msg, DEVLINK_ATTR_PARAM_VALUE_DATA,
+				   val.vstr))
+			goto value_nest_cancel;
+		break;
+	case DEVLINK_PARAM_TYPE_BOOL:
+		if (val.vbool &&
+		    nla_put_flag(msg, DEVLINK_ATTR_PARAM_VALUE_DATA))
+			goto value_nest_cancel;
+		break;
+	}
+
+	nla_nest_end(msg, param_value_attr);
+	return 0;
+
+value_nest_cancel:
+	nla_nest_cancel(msg, param_value_attr);
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink,
+				 struct devlink_param_item *param_item,
+				 enum devlink_command cmd,
+				 u32 portid, u32 seq, int flags)
+{
+	union devlink_param_value param_value[DEVLINK_PARAM_CMODE_MAX + 1];
+	const struct devlink_param *param = param_item->param;
+	struct devlink_param_gset_ctx ctx;
+	struct nlattr *param_values_list;
+	struct nlattr *param_attr;
+	int nla_type;
+	void *hdr;
+	int err;
+	int i;
+
+	/* Get value from driver part to driverinit configuration mode */
+	for (i = 0; i <= DEVLINK_PARAM_CMODE_MAX; i++) {
+		if (!devlink_param_cmode_is_supported(param, i))
+			continue;
+		if (i == DEVLINK_PARAM_CMODE_DRIVERINIT) {
+			if (!param_item->driverinit_value_valid)
+				return -EOPNOTSUPP;
+			param_value[i] = param_item->driverinit_value;
+		} else {
+			ctx.cmode = i;
+			err = devlink_param_get(devlink, param, &ctx);
+			if (err)
+				return err;
+			param_value[i] = ctx.val;
+		}
+	}
+
+	hdr = genlmsg_put(msg, portid, seq, &devlink_nl_family, flags, cmd);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	if (devlink_nl_put_handle(msg, devlink))
+		goto genlmsg_cancel;
+	param_attr = nla_nest_start(msg, DEVLINK_ATTR_PARAM);
+	if (!param_attr)
+		goto genlmsg_cancel;
+	if (nla_put_string(msg, DEVLINK_ATTR_PARAM_NAME, param->name))
+		goto param_nest_cancel;
+	if (param->generic && nla_put_flag(msg, DEVLINK_ATTR_PARAM_GENERIC))
+		goto param_nest_cancel;
+
+	nla_type = devlink_param_type_to_nla_type(param->type);
+	if (nla_type < 0)
+		goto param_nest_cancel;
+	if (nla_put_u8(msg, DEVLINK_ATTR_PARAM_TYPE, nla_type))
+		goto param_nest_cancel;
+
+	param_values_list = nla_nest_start(msg, DEVLINK_ATTR_PARAM_VALUES_LIST);
+	if (!param_values_list)
+		goto param_nest_cancel;
+
+	for (i = 0; i <= DEVLINK_PARAM_CMODE_MAX; i++) {
+		if (!devlink_param_cmode_is_supported(param, i))
+			continue;
+		err = devlink_nl_param_value_fill_one(msg, param->type,
+						      i, param_value[i]);
+		if (err)
+			goto values_list_nest_cancel;
+	}
+
+	nla_nest_end(msg, param_values_list);
+	nla_nest_end(msg, param_attr);
+	genlmsg_end(msg, hdr);
+	return 0;
+
+values_list_nest_cancel:
+	nla_nest_end(msg, param_values_list);
+param_nest_cancel:
+	nla_nest_cancel(msg, param_attr);
+genlmsg_cancel:
+	genlmsg_cancel(msg, hdr);
+	return -EMSGSIZE;
+}
+
+static void devlink_param_notify(struct devlink *devlink,
+				 struct devlink_param_item *param_item,
+				 enum devlink_command cmd)
+{
+	struct sk_buff *msg;
+	int err;
+
+	WARN_ON(cmd != DEVLINK_CMD_PARAM_NEW && cmd != DEVLINK_CMD_PARAM_DEL);
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg)
+		return;
+	err = devlink_nl_param_fill(msg, devlink, param_item, cmd, 0, 0, 0);
+	if (err) {
+		nlmsg_free(msg);
+		return;
+	}
+
+	genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink),
+				msg, 0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);
+}
+
+static int devlink_nl_cmd_param_get_dumpit(struct sk_buff *msg,
+					   struct netlink_callback *cb)
+{
+	struct devlink_param_item *param_item;
+	struct devlink *devlink;
+	int start = cb->args[0];
+	int idx = 0;
+	int err;
+
+	mutex_lock(&devlink_mutex);
+	list_for_each_entry(devlink, &devlink_list, list) {
+		if (!net_eq(devlink_net(devlink), sock_net(msg->sk)))
+			continue;
+		mutex_lock(&devlink->lock);
+		list_for_each_entry(param_item, &devlink->param_list, list) {
+			if (idx < start) {
+				idx++;
+				continue;
+			}
+			err = devlink_nl_param_fill(msg, devlink, param_item,
+						    DEVLINK_CMD_PARAM_GET,
+						    NETLINK_CB(cb->skb).portid,
+						    cb->nlh->nlmsg_seq,
+						    NLM_F_MULTI);
+			if (err) {
+				mutex_unlock(&devlink->lock);
+				goto out;
+			}
+			idx++;
+		}
+		mutex_unlock(&devlink->lock);
+	}
+out:
+	mutex_unlock(&devlink_mutex);
+
+	cb->args[0] = idx;
+	return msg->len;
+}
+
+static int
+devlink_param_type_get_from_info(struct genl_info *info,
+				 enum devlink_param_type *param_type)
+{
+	if (!info->attrs[DEVLINK_ATTR_PARAM_TYPE])
+		return -EINVAL;
+
+	switch (nla_get_u8(info->attrs[DEVLINK_ATTR_PARAM_TYPE])) {
+	case NLA_U8:
+		*param_type = DEVLINK_PARAM_TYPE_U8;
+		break;
+	case NLA_U16:
+		*param_type = DEVLINK_PARAM_TYPE_U16;
+		break;
+	case NLA_U32:
+		*param_type = DEVLINK_PARAM_TYPE_U32;
+		break;
+	case NLA_STRING:
+		*param_type = DEVLINK_PARAM_TYPE_STRING;
+		break;
+	case NLA_FLAG:
+		*param_type = DEVLINK_PARAM_TYPE_BOOL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int
+devlink_param_value_get_from_info(const struct devlink_param *param,
+				  struct genl_info *info,
+				  union devlink_param_value *value)
+{
+	if (param->type != DEVLINK_PARAM_TYPE_BOOL &&
+	    !info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA])
+		return -EINVAL;
+
+	switch (param->type) {
+	case DEVLINK_PARAM_TYPE_U8:
+		value->vu8 = nla_get_u8(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
+		break;
+	case DEVLINK_PARAM_TYPE_U16:
+		value->vu16 = nla_get_u16(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
+		break;
+	case DEVLINK_PARAM_TYPE_U32:
+		value->vu32 = nla_get_u32(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
+		break;
+	case DEVLINK_PARAM_TYPE_STRING:
+		if (nla_len(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]) >
+		    DEVLINK_PARAM_MAX_STRING_VALUE)
+			return -EINVAL;
+		value->vstr = nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
+		break;
+	case DEVLINK_PARAM_TYPE_BOOL:
+		value->vbool = info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA] ?
+			       true : false;
+		break;
+	}
+	return 0;
+}
+
+static struct devlink_param_item *
+devlink_param_get_from_info(struct devlink *devlink,
+			    struct genl_info *info)
+{
+	char *param_name;
+
+	if (!info->attrs[DEVLINK_ATTR_PARAM_NAME])
+		return NULL;
+
+	param_name = nla_data(info->attrs[DEVLINK_ATTR_PARAM_NAME]);
+	return devlink_param_find_by_name(&devlink->param_list, param_name);
+}
+
+static int devlink_nl_cmd_param_get_doit(struct sk_buff *skb,
+					 struct genl_info *info)
+{
+	struct devlink *devlink = info->user_ptr[0];
+	struct devlink_param_item *param_item;
+	struct sk_buff *msg;
+	int err;
+
+	param_item = devlink_param_get_from_info(devlink, info);
+	if (!param_item)
+		return -EINVAL;
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	err = devlink_nl_param_fill(msg, devlink, param_item,
+				    DEVLINK_CMD_PARAM_GET,
+				    info->snd_portid, info->snd_seq, 0);
+	if (err) {
+		nlmsg_free(msg);
+		return err;
+	}
+
+	return genlmsg_reply(msg, info);
+}
+
+static int devlink_nl_cmd_param_set_doit(struct sk_buff *skb,
+					 struct genl_info *info)
+{
+	struct devlink *devlink = info->user_ptr[0];
+	enum devlink_param_type param_type;
+	struct devlink_param_gset_ctx ctx;
+	enum devlink_param_cmode cmode;
+	struct devlink_param_item *param_item;
+	const struct devlink_param *param;
+	union devlink_param_value value;
+	int err = 0;
+
+	param_item = devlink_param_get_from_info(devlink, info);
+	if (!param_item)
+		return -EINVAL;
+	param = param_item->param;
+	err = devlink_param_type_get_from_info(info, &param_type);
+	if (err)
+		return err;
+	if (param_type != param->type)
+		return -EINVAL;
+	err = devlink_param_value_get_from_info(param, info, &value);
+	if (err)
+		return err;
+	if (param->validate) {
+		err = param->validate(devlink, param->id, value, info->extack);
+		if (err)
+			return err;
+	}
+
+	if (!info->attrs[DEVLINK_ATTR_PARAM_VALUE_CMODE])
+		return -EINVAL;
+	cmode = nla_get_u8(info->attrs[DEVLINK_ATTR_PARAM_VALUE_CMODE]);
+	if (!devlink_param_cmode_is_supported(param, cmode))
+		return -EOPNOTSUPP;
+
+	if (cmode == DEVLINK_PARAM_CMODE_DRIVERINIT) {
+		param_item->driverinit_value = value;
+		param_item->driverinit_value_valid = true;
+	} else {
+		if (!param->set)
+			return -EOPNOTSUPP;
+		ctx.val = value;
+		ctx.cmode = cmode;
+		err = devlink_param_set(devlink, param, &ctx);
+		if (err)
+			return err;
+	}
+
+	devlink_param_notify(devlink, param_item, DEVLINK_CMD_PARAM_NEW);
+	return 0;
+}
+
+static int devlink_param_register_one(struct devlink *devlink,
+				      const struct devlink_param *param)
+{
+	struct devlink_param_item *param_item;
+
+	if (devlink_param_find_by_name(&devlink->param_list,
+				       param->name))
+		return -EEXIST;
+
+	if (param->supported_cmodes == BIT(DEVLINK_PARAM_CMODE_DRIVERINIT))
+		WARN_ON(param->get || param->set);
+	else
+		WARN_ON(!param->get || !param->set);
+
+	param_item = kzalloc(sizeof(*param_item), GFP_KERNEL);
+	if (!param_item)
+		return -ENOMEM;
+	param_item->param = param;
+
+	list_add_tail(&param_item->list, &devlink->param_list);
+	devlink_param_notify(devlink, param_item, DEVLINK_CMD_PARAM_NEW);
+	return 0;
+}
+
+static void devlink_param_unregister_one(struct devlink *devlink,
+					 const struct devlink_param *param)
+{
+	struct devlink_param_item *param_item;
+
+	param_item = devlink_param_find_by_name(&devlink->param_list,
+						param->name);
+	WARN_ON(!param_item);
+	devlink_param_notify(devlink, param_item, DEVLINK_CMD_PARAM_DEL);
+	list_del(&param_item->list);
+	kfree(param_item);
+}
+
 static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING },
 	[DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING },
@@ -2624,6 +3118,9 @@ static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
 	[DEVLINK_ATTR_DPIPE_TABLE_COUNTERS_ENABLED] = { .type = NLA_U8 },
 	[DEVLINK_ATTR_RESOURCE_ID] = { .type = NLA_U64},
 	[DEVLINK_ATTR_RESOURCE_SIZE] = { .type = NLA_U64},
+	[DEVLINK_ATTR_PARAM_NAME] = { .type = NLA_NUL_STRING },
+	[DEVLINK_ATTR_PARAM_TYPE] = { .type = NLA_U8 },
+	[DEVLINK_ATTR_PARAM_VALUE_CMODE] = { .type = NLA_U8 },
 };
 
 static const struct genl_ops devlink_nl_ops[] = {
@@ -2807,6 +3304,21 @@ static const struct genl_ops devlink_nl_ops[] = {
 		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK |
 				  DEVLINK_NL_FLAG_NO_LOCK,
 	},
+	{
+		.cmd = DEVLINK_CMD_PARAM_GET,
+		.doit = devlink_nl_cmd_param_get_doit,
+		.dumpit = devlink_nl_cmd_param_get_dumpit,
+		.policy = devlink_nl_policy,
+		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK,
+		/* can be retrieved by unprivileged users */
+	},
+	{
+		.cmd = DEVLINK_CMD_PARAM_SET,
+		.doit = devlink_nl_cmd_param_set_doit,
+		.policy = devlink_nl_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK,
+	},
 };
 
 static struct genl_family devlink_nl_family __ro_after_init = {
@@ -2845,6 +3357,7 @@ struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size)
 	INIT_LIST_HEAD(&devlink->sb_list);
 	INIT_LIST_HEAD_RCU(&devlink->dpipe_table_list);
 	INIT_LIST_HEAD(&devlink->resource_list);
+	INIT_LIST_HEAD(&devlink->param_list);
 	mutex_init(&devlink->lock);
 	return devlink;
 }
@@ -3434,6 +3947,168 @@ out:
 }
 EXPORT_SYMBOL_GPL(devlink_resource_occ_get_unregister);
 
+/**
+ *	devlink_params_register - register configuration parameters
+ *
+ *	@devlink: devlink
+ *	@params: configuration parameters array
+ *	@params_count: number of parameters provided
+ *
+ *	Register the configuration parameters supported by the driver.
+ */
+int devlink_params_register(struct devlink *devlink,
+			    const struct devlink_param *params,
+			    size_t params_count)
+{
+	const struct devlink_param *param = params;
+	int i;
+	int err;
+
+	mutex_lock(&devlink->lock);
+	for (i = 0; i < params_count; i++, param++) {
+		if (!param || !param->name || !param->supported_cmodes) {
+			err = -EINVAL;
+			goto rollback;
+		}
+		if (param->generic) {
+			err = devlink_param_generic_verify(param);
+			if (err)
+				goto rollback;
+		} else {
+			err = devlink_param_driver_verify(param);
+			if (err)
+				goto rollback;
+		}
+		err = devlink_param_register_one(devlink, param);
+		if (err)
+			goto rollback;
+	}
+
+	mutex_unlock(&devlink->lock);
+	return 0;
+
+rollback:
+	if (!i)
+		goto unlock;
+	for (param--; i > 0; i--, param--)
+		devlink_param_unregister_one(devlink, param);
+unlock:
+	mutex_unlock(&devlink->lock);
+	return err;
+}
+EXPORT_SYMBOL_GPL(devlink_params_register);
+
+/**
+ *	devlink_params_unregister - unregister configuration parameters
+ *	@devlink: devlink
+ *	@params: configuration parameters to unregister
+ *	@params_count: number of parameters provided
+ */
+void devlink_params_unregister(struct devlink *devlink,
+			       const struct devlink_param *params,
+			       size_t params_count)
+{
+	const struct devlink_param *param = params;
+	int i;
+
+	mutex_lock(&devlink->lock);
+	for (i = 0; i < params_count; i++, param++)
+		devlink_param_unregister_one(devlink, param);
+	mutex_unlock(&devlink->lock);
+}
+EXPORT_SYMBOL_GPL(devlink_params_unregister);
+
+/**
+ *	devlink_param_driverinit_value_get - get configuration parameter
+ *					     value for driver initializing
+ *
+ *	@devlink: devlink
+ *	@param_id: parameter ID
+ *	@init_val: value of parameter in driverinit configuration mode
+ *
+ *	This function should be used by the driver to get driverinit
+ *	configuration for initialization after reload command.
+ */
+int devlink_param_driverinit_value_get(struct devlink *devlink, u32 param_id,
+				       union devlink_param_value *init_val)
+{
+	struct devlink_param_item *param_item;
+
+	if (!devlink->ops || !devlink->ops->reload)
+		return -EOPNOTSUPP;
+
+	param_item = devlink_param_find_by_id(&devlink->param_list, param_id);
+	if (!param_item)
+		return -EINVAL;
+
+	if (!param_item->driverinit_value_valid ||
+	    !devlink_param_cmode_is_supported(param_item->param,
+					      DEVLINK_PARAM_CMODE_DRIVERINIT))
+		return -EOPNOTSUPP;
+
+	*init_val = param_item->driverinit_value;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devlink_param_driverinit_value_get);
+
+/**
+ *	devlink_param_driverinit_value_set - set value of configuration
+ *					     parameter for driverinit
+ *					     configuration mode
+ *
+ *	@devlink: devlink
+ *	@param_id: parameter ID
+ *	@init_val: value of parameter to set for driverinit configuration mode
+ *
+ *	This function should be used by the driver to set driverinit
+ *	configuration mode default value.
+ */
+int devlink_param_driverinit_value_set(struct devlink *devlink, u32 param_id,
+				       union devlink_param_value init_val)
+{
+	struct devlink_param_item *param_item;
+
+	param_item = devlink_param_find_by_id(&devlink->param_list, param_id);
+	if (!param_item)
+		return -EINVAL;
+
+	if (!devlink_param_cmode_is_supported(param_item->param,
+					      DEVLINK_PARAM_CMODE_DRIVERINIT))
+		return -EOPNOTSUPP;
+
+	param_item->driverinit_value = init_val;
+	param_item->driverinit_value_valid = true;
+
+	devlink_param_notify(devlink, param_item, DEVLINK_CMD_PARAM_NEW);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devlink_param_driverinit_value_set);
+
+/**
+ *	devlink_param_value_changed - notify devlink on a parameter's value
+ *				      change. Should be called by the driver
+ *				      right after the change.
+ *
+ *	@devlink: devlink
+ *	@param_id: parameter ID
+ *
+ *	This function should be used by the driver to notify devlink on value
+ *	change, excluding driverinit configuration mode.
+ *	For driverinit configuration mode driver should use the function
+ *	devlink_param_driverinit_value_set() instead.
+ */
+void devlink_param_value_changed(struct devlink *devlink, u32 param_id)
+{
+	struct devlink_param_item *param_item;
+
+	param_item = devlink_param_find_by_id(&devlink->param_list, param_id);
+	WARN_ON(!param_item);
+
+	devlink_param_notify(devlink, param_item, DEVLINK_CMD_PARAM_NEW);
+}
+EXPORT_SYMBOL_GPL(devlink_param_value_changed);
+
 static int __init devlink_module_init(void)
 {
 	return genl_register_family(&devlink_nl_family);