Commit afd888c3 authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
Browse files

devlink: make sure driver does not read updated driverinit param before reload 



The driverinit param purpose is to serve the driver during init/reload
time to provide a value, either default or set by user.

Make sure that driver does not read value updated by user before the
reload is performed. Hold the new value in a separate struct and switch
it during reload.

Note that this is required to be eventually possible to call
devl_param_driverinit_value_get() without holding instance lock.

Signed-off-by: default avatarJiri Pirko <jiri@nvidia.com>
Reviewed-by: default avatarSimon Horman <simon.horman@corigine.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent fa2f921f

include/net/devlink.h

+4 −0
Original line number Diff line number Diff line
@@ -489,6 +489,10 @@ struct devlink_param_item { 
	const struct devlink_param *param;

	union devlink_param_value driverinit_value;

	bool driverinit_value_valid;

	union devlink_param_value driverinit_value_new; /* Not reachable

							 * until reload.

							 */

	bool driverinit_value_new_valid;

};



enum devlink_param_generic_id {

net/devlink/dev.c

+3 −0
Original line number Diff line number Diff line
@@ -369,6 +369,9 @@ int devlink_reload(struct devlink *devlink, struct net *dest_net, 
	if (dest_net && !net_eq(dest_net, curr_net))

		devlink_reload_netns_change(devlink, curr_net, dest_net);



	if (action == DEVLINK_RELOAD_ACTION_DRIVER_REINIT)

		devlink_params_driverinit_load_new(devlink);



	err = devlink->ops->reload_up(devlink, action, limit, actions_performed, extack);

	devlink_reload_failed_set(devlink, !!err);

	if (err)

net/devlink/devl_internal.h

+3 −0
Original line number Diff line number Diff line
@@ -189,6 +189,9 @@ static inline bool devlink_reload_supported(const struct devlink_ops *ops) 
	return ops->reload_down && ops->reload_up;

}



/* Params */

void devlink_params_driverinit_load_new(struct devlink *devlink);



/* Resources */

struct devlink_resource;

int devlink_resources_validate(struct devlink *devlink,

net/devlink/leftover.c

+22 −4
Original line number Diff line number Diff line
@@ -4097,9 +4097,12 @@ static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink, 
		if (!devlink_param_cmode_is_supported(param, i))

			continue;

		if (i == DEVLINK_PARAM_CMODE_DRIVERINIT) {

			if (!param_item->driverinit_value_valid)

				return -EOPNOTSUPP;

			if (param_item->driverinit_value_new_valid)

				param_value[i] = param_item->driverinit_value_new;

			else if (param_item->driverinit_value_valid)

				param_value[i] = param_item->driverinit_value;

			else

				return -EOPNOTSUPP;

		} else {

			ctx.cmode = i;

			err = devlink_param_get(devlink, param, &ctx);
@@ -4387,8 +4390,8 @@ static int __devlink_nl_cmd_param_set_doit(struct devlink *devlink, 
		return -EOPNOTSUPP;



	if (cmode == DEVLINK_PARAM_CMODE_DRIVERINIT) {

		param_item->driverinit_value = value;

		param_item->driverinit_value_valid = true;

		param_item->driverinit_value_new = value;

		param_item->driverinit_value_new_valid = true;

	} else {

		if (!param->set)

			return -EOPNOTSUPP;
@@ -9690,6 +9693,21 @@ void devl_param_driverinit_value_set(struct devlink *devlink, u32 param_id, 
}

EXPORT_SYMBOL_GPL(devl_param_driverinit_value_set);



void devlink_params_driverinit_load_new(struct devlink *devlink)

{

	struct devlink_param_item *param_item;



	list_for_each_entry(param_item, &devlink->param_list, list) {

		if (!devlink_param_cmode_is_supported(param_item->param,

						      DEVLINK_PARAM_CMODE_DRIVERINIT) ||

		    !param_item->driverinit_value_new_valid)

			continue;

		param_item->driverinit_value = param_item->driverinit_value_new;

		param_item->driverinit_value_valid = true;

		param_item->driverinit_value_new_valid = false;

	}

}



/**

 *	devl_param_value_changed - notify devlink on a parameter's value

 *				   change. Should be called by the driver