devlink: convert param list to xarray

Loose the linked list for params and use xarray instead.

Note that this is required to be eventually possible to call
devl_param_driverinit_value_get() without holding instance lock.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/devlink/core.c

@@ -212,6 +212,7 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
 	devlink->dev = dev;
 	devlink->ops = ops;
 	xa_init_flags(&devlink->ports, XA_FLAGS_ALLOC);
+	xa_init_flags(&devlink->params, XA_FLAGS_ALLOC);
 	xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
 	write_pnet(&devlink->_net, net);
 	INIT_LIST_HEAD(&devlink->rate_list);
@@ -219,7 +220,6 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
 	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);
 	INIT_LIST_HEAD(&devlink->region_list);
 	INIT_LIST_HEAD(&devlink->reporter_list);
 	INIT_LIST_HEAD(&devlink->trap_list);
@@ -255,7 +255,6 @@ void devlink_free(struct devlink *devlink)
 	WARN_ON(!list_empty(&devlink->trap_list));
 	WARN_ON(!list_empty(&devlink->reporter_list));
 	WARN_ON(!list_empty(&devlink->region_list));
-	WARN_ON(!list_empty(&devlink->param_list));
 	WARN_ON(!list_empty(&devlink->resource_list));
 	WARN_ON(!list_empty(&devlink->dpipe_table_list));
 	WARN_ON(!list_empty(&devlink->sb_list));
@@ -264,6 +263,7 @@ void devlink_free(struct devlink *devlink)
 	WARN_ON(!xa_empty(&devlink->ports));
 
 	xa_destroy(&devlink->snapshot_ids);
+	xa_destroy(&devlink->params);
 	xa_destroy(&devlink->ports);
 
 	WARN_ON_ONCE(unregister_netdevice_notifier(&devlink->netdevice_nb));

net/devlink/devl_internal.h

@@ -29,7 +29,7 @@ struct devlink {
 	struct list_head sb_list;
 	struct list_head dpipe_table_list;
 	struct list_head resource_list;
-	struct list_head param_list;
+	struct xarray params;
 	struct list_head region_list;
 	struct list_head reporter_list;
 	struct devlink_dpipe_headers *dpipe_headers;

net/devlink/leftover.c

@@ -3953,26 +3953,22 @@ static int devlink_param_driver_verify(const struct devlink_param *param)
 }
 
 static struct devlink_param_item *
-devlink_param_find_by_name(struct list_head *param_list,
-			   const char *param_name)
+devlink_param_find_by_name(struct xarray *params, const char *param_name)
 {
 	struct devlink_param_item *param_item;
+	unsigned long param_id;
 
-	list_for_each_entry(param_item, param_list, list)
+	xa_for_each(params, param_id, param_item) {
 		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)
+devlink_param_find_by_id(struct xarray *params, 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;
+	return xa_load(params, param_id);
 }
 
 static bool
@@ -4201,14 +4197,10 @@ devlink_nl_cmd_param_get_dump_one(struct sk_buff *msg, struct devlink *devlink,
 {
 	struct devlink_nl_dump_state *state = devlink_dump_state(cb);
 	struct devlink_param_item *param_item;
-	int idx = 0;
+	unsigned long param_id;
 	int err = 0;
 
-	list_for_each_entry(param_item, &devlink->param_list, list) {
-		if (idx < state->idx) {
-			idx++;
-			continue;
-		}
+	xa_for_each_start(&devlink->params, param_id, param_item, state->idx) {
 		err = devlink_nl_param_fill(msg, devlink, 0, param_item,
 					    DEVLINK_CMD_PARAM_GET,
 					    NETLINK_CB(cb->skb).portid,
@@ -4217,10 +4209,9 @@ devlink_nl_cmd_param_get_dump_one(struct sk_buff *msg, struct devlink *devlink,
 		if (err == -EOPNOTSUPP) {
 			err = 0;
 		} else if (err) {
-			state->idx = idx;
+			state->idx = param_id;
 			break;
 		}
-		idx++;
 	}
 
 	return err;
@@ -4306,8 +4297,7 @@ devlink_param_value_get_from_info(const struct devlink_param *param,
 }
 
 static struct devlink_param_item *
-devlink_param_get_from_info(struct list_head *param_list,
-			    struct genl_info *info)
+devlink_param_get_from_info(struct xarray *params, struct genl_info *info)
 {
 	char *param_name;
 
@@ -4315,7 +4305,7 @@ devlink_param_get_from_info(struct list_head *param_list,
 		return NULL;
 
 	param_name = nla_data(info->attrs[DEVLINK_ATTR_PARAM_NAME]);
-	return devlink_param_find_by_name(param_list, param_name);
+	return devlink_param_find_by_name(params, param_name);
 }
 
 static int devlink_nl_cmd_param_get_doit(struct sk_buff *skb,
@@ -4326,7 +4316,7 @@ static int devlink_nl_cmd_param_get_doit(struct sk_buff *skb,
 	struct sk_buff *msg;
 	int err;
 
-	param_item = devlink_param_get_from_info(&devlink->param_list, info);
+	param_item = devlink_param_get_from_info(&devlink->params, info);
 	if (!param_item)
 		return -EINVAL;
 
@@ -4347,7 +4337,7 @@ static int devlink_nl_cmd_param_get_doit(struct sk_buff *skb,
 
 static int __devlink_nl_cmd_param_set_doit(struct devlink *devlink,
 					   unsigned int port_index,
-					   struct list_head *param_list,
+					   struct xarray *params,
 					   struct genl_info *info,
 					   enum devlink_command cmd)
 {
@@ -4359,7 +4349,7 @@ static int __devlink_nl_cmd_param_set_doit(struct devlink *devlink,
 	union devlink_param_value value;
 	int err = 0;
 
-	param_item = devlink_param_get_from_info(param_list, info);
+	param_item = devlink_param_get_from_info(params, info);
 	if (!param_item)
 		return -EINVAL;
 	param = param_item->param;
@@ -4405,7 +4395,7 @@ static int devlink_nl_cmd_param_set_doit(struct sk_buff *skb,
 {
 	struct devlink *devlink = info->user_ptr[0];
 
-	return __devlink_nl_cmd_param_set_doit(devlink, 0, &devlink->param_list,
+	return __devlink_nl_cmd_param_set_doit(devlink, 0, &devlink->params,
 					       info, DEVLINK_CMD_PARAM_NEW);
 }
 
@@ -8037,6 +8027,7 @@ void devlink_notify_register(struct devlink *devlink)
 	struct devlink_rate *rate_node;
 	struct devlink_region *region;
 	unsigned long port_index;
+	unsigned long param_id;
 
 	devlink_notify(devlink, DEVLINK_CMD_NEW);
 	list_for_each_entry(linecard, &devlink->linecard_list, list)
@@ -8062,7 +8053,7 @@ void devlink_notify_register(struct devlink *devlink)
 	list_for_each_entry(region, &devlink->region_list, list)
 		devlink_nl_region_notify(region, NULL, DEVLINK_CMD_REGION_NEW);
 
-	list_for_each_entry(param_item, &devlink->param_list, list)
+	xa_for_each(&devlink->params, param_id, param_item)
 		devlink_param_notify(devlink, 0, param_item,
 				     DEVLINK_CMD_PARAM_NEW);
 }
@@ -8077,8 +8068,9 @@ void devlink_notify_unregister(struct devlink *devlink)
 	struct devlink_rate *rate_node;
 	struct devlink_region *region;
 	unsigned long port_index;
+	unsigned long param_id;
 
-	list_for_each_entry_reverse(param_item, &devlink->param_list, list)
+	xa_for_each(&devlink->params, param_id, param_item)
 		devlink_param_notify(devlink, 0, param_item,
 				     DEVLINK_CMD_PARAM_DEL);
 
@@ -9505,9 +9497,10 @@ static int devlink_param_register(struct devlink *devlink,
 				  const struct devlink_param *param)
 {
 	struct devlink_param_item *param_item;
+	int err;
 
 	WARN_ON(devlink_param_verify(param));
-	WARN_ON(devlink_param_find_by_name(&devlink->param_list, param->name));
+	WARN_ON(devlink_param_find_by_name(&devlink->params, param->name));
 
 	if (param->supported_cmodes == BIT(DEVLINK_PARAM_CMODE_DRIVERINIT))
 		WARN_ON(param->get || param->set);
@@ -9520,9 +9513,16 @@ static int devlink_param_register(struct devlink *devlink,
 
 	param_item->param = param;
 
-	list_add_tail(&param_item->list, &devlink->param_list);
+	err = xa_insert(&devlink->params, param->id, param_item, GFP_KERNEL);
+	if (err)
+		goto err_xa_insert;
+
 	devlink_param_notify(devlink, 0, param_item, DEVLINK_CMD_PARAM_NEW);
 	return 0;
+
+err_xa_insert:
+	kfree(param_item);
+	return err;
 }
 
 static void devlink_param_unregister(struct devlink *devlink,
@@ -9530,12 +9530,11 @@ static void devlink_param_unregister(struct devlink *devlink,
 {
 	struct devlink_param_item *param_item;
 
-	param_item =
-		devlink_param_find_by_name(&devlink->param_list, param->name);
+	param_item = devlink_param_find_by_id(&devlink->params, param->id);
 	if (WARN_ON(!param_item))
 		return;
 	devlink_param_notify(devlink, 0, param_item, DEVLINK_CMD_PARAM_DEL);
-	list_del(&param_item->list);
+	xa_erase(&devlink->params, param->id);
 	kfree(param_item);
 }
 
@@ -9639,7 +9638,7 @@ int devl_param_driverinit_value_get(struct devlink *devlink, u32 param_id,
 	if (WARN_ON(!devlink_reload_supported(devlink->ops)))
 		return -EOPNOTSUPP;
 
-	param_item = devlink_param_find_by_id(&devlink->param_list, param_id);
+	param_item = devlink_param_find_by_id(&devlink->params, param_id);
 	if (!param_item)
 		return -EINVAL;
 
@@ -9673,7 +9672,7 @@ void devl_param_driverinit_value_set(struct devlink *devlink, u32 param_id,
 {
 	struct devlink_param_item *param_item;
 
-	param_item = devlink_param_find_by_id(&devlink->param_list, param_id);
+	param_item = devlink_param_find_by_id(&devlink->params, param_id);
 	if (WARN_ON(!param_item))
 		return;
 
@@ -9691,8 +9690,9 @@ EXPORT_SYMBOL_GPL(devl_param_driverinit_value_set);
 void devlink_params_driverinit_load_new(struct devlink *devlink)
 {
 	struct devlink_param_item *param_item;
+	unsigned long param_id;
 
-	list_for_each_entry(param_item, &devlink->param_list, list) {
+	xa_for_each(&devlink->params, param_id, param_item) {
 		if (!devlink_param_cmode_is_supported(param_item->param,
 						      DEVLINK_PARAM_CMODE_DRIVERINIT) ||
 		    !param_item->driverinit_value_new_valid)
@@ -9719,7 +9719,7 @@ void devl_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);
+	param_item = devlink_param_find_by_id(&devlink->params, param_id);
 	WARN_ON(!param_item);
 
 	devlink_param_notify(devlink, 0, param_item, DEVLINK_CMD_PARAM_NEW);