Commit d41c9dbd authored by Jiri Pirko's avatar Jiri Pirko Committed by Jakub Kicinski
Browse files

net: devlink: take RTNL in port_fill() function only if it is not held 



Follow-up patch is going to introduce a netdevice notifier event
processing which is called with RTNL mutex held. Processing of this will
eventually lead to call to port_notity() and port_fill() which currently
takes RTNL mutex internally. So as a temporary solution, propagate a
bool indicating if the mutex is already held. This will go away in one
of the follow-up patches.

Signed-off-by: default avatarJiri Pirko <jiri@nvidia.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 45791e0d

net/core/devlink.c

+31 −15
Original line number Diff line number Diff line
@@ -1278,7 +1278,8 @@ devlink_nl_port_function_attrs_put(struct sk_buff *msg, struct devlink_port *por 
static int devlink_nl_port_fill(struct sk_buff *msg,

				struct devlink_port *devlink_port,

				enum devlink_command cmd, u32 portid, u32 seq,

				int flags, struct netlink_ext_ack *extack)

				int flags, struct netlink_ext_ack *extack,

				bool rtnl_held)

{

	struct devlink *devlink = devlink_port->devlink;

	void *hdr;
@@ -1293,6 +1294,7 @@ static int devlink_nl_port_fill(struct sk_buff *msg, 
		goto nla_put_failure;



	/* Hold rtnl lock while accessing port's netdev attributes. */

	if (!rtnl_held)

		rtnl_lock();

	spin_lock_bh(&devlink_port->type_lock);

	if (nla_put_u16(msg, DEVLINK_ATTR_PORT_TYPE, devlink_port->type))
@@ -1321,6 +1323,7 @@ static int devlink_nl_port_fill(struct sk_buff *msg, 
			goto nla_put_failure_type_locked;

	}

	spin_unlock_bh(&devlink_port->type_lock);

	if (!rtnl_held)

		rtnl_unlock();

	if (devlink_nl_port_attrs_put(msg, devlink_port))

		goto nla_put_failure;
@@ -1336,14 +1339,15 @@ static int devlink_nl_port_fill(struct sk_buff *msg, 


nla_put_failure_type_locked:

	spin_unlock_bh(&devlink_port->type_lock);

	if (!rtnl_held)

		rtnl_unlock();

nla_put_failure:

	genlmsg_cancel(msg, hdr);

	return -EMSGSIZE;

}



static void devlink_port_notify(struct devlink_port *devlink_port,

				enum devlink_command cmd)

static void __devlink_port_notify(struct devlink_port *devlink_port,

				  enum devlink_command cmd, bool rtnl_held)

{

	struct devlink *devlink = devlink_port->devlink;

	struct sk_buff *msg;
@@ -1358,7 +1362,8 @@ static void devlink_port_notify(struct devlink_port *devlink_port, 
	if (!msg)

		return;



	err = devlink_nl_port_fill(msg, devlink_port, cmd, 0, 0, 0, NULL);

	err = devlink_nl_port_fill(msg, devlink_port, cmd, 0, 0, 0, NULL,

				   rtnl_held);

	if (err) {

		nlmsg_free(msg);

		return;
@@ -1368,6 +1373,12 @@ static void devlink_port_notify(struct devlink_port *devlink_port, 
				0, DEVLINK_MCGRP_CONFIG, GFP_KERNEL);

}



static void devlink_port_notify(struct devlink_port *devlink_port,

				enum devlink_command cmd)

{

	__devlink_port_notify(devlink_port, cmd, false);

}



static void devlink_rate_notify(struct devlink_rate *devlink_rate,

				enum devlink_command cmd)

{
@@ -1531,7 +1542,7 @@ static int devlink_nl_cmd_port_get_doit(struct sk_buff *skb, 


	err = devlink_nl_port_fill(msg, devlink_port, DEVLINK_CMD_PORT_NEW,

				   info->snd_portid, info->snd_seq, 0,

				   info->extack);

				   info->extack, false);

	if (err) {

		nlmsg_free(msg);

		return err;
@@ -1561,7 +1572,8 @@ static int devlink_nl_cmd_port_get_dumpit(struct sk_buff *msg, 
						   DEVLINK_CMD_NEW,

						   NETLINK_CB(cb->skb).portid,

						   cb->nlh->nlmsg_seq,

						   NLM_F_MULTI, cb->extack);

						   NLM_F_MULTI, cb->extack,

						   false);

			if (err) {

				devl_unlock(devlink);

				devlink_put(devlink);
@@ -1773,7 +1785,8 @@ static int devlink_port_new_notify(struct devlink *devlink, 
	}



	err = devlink_nl_port_fill(msg, devlink_port, DEVLINK_CMD_NEW,

				   info->snd_portid, info->snd_seq, 0, NULL);

				   info->snd_portid, info->snd_seq, 0, NULL,

				   false);

	if (err)

		goto out;
@@ -10033,7 +10046,7 @@ static void devlink_port_type_netdev_checks(struct devlink_port *devlink_port, 


static void __devlink_port_type_set(struct devlink_port *devlink_port,

				    enum devlink_port_type type,

				    void *type_dev)

				    void *type_dev, bool rtnl_held)

{

	struct net_device *netdev = type_dev;
@@ -10060,7 +10073,7 @@ static void __devlink_port_type_set(struct devlink_port *devlink_port, 
		break;

	}

	spin_unlock_bh(&devlink_port->type_lock);

	devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW);

	__devlink_port_notify(devlink_port, DEVLINK_CMD_PORT_NEW, rtnl_held);

}



/**
@@ -10077,7 +10090,8 @@ void devlink_port_type_eth_set(struct devlink_port *devlink_port, 
			 "devlink port type for port %d set to Ethernet without a software interface reference, device type not supported by the kernel?\n",

			 devlink_port->index);



	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev);

	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev,

				false);

}

EXPORT_SYMBOL_GPL(devlink_port_type_eth_set);
@@ -10090,7 +10104,8 @@ EXPORT_SYMBOL_GPL(devlink_port_type_eth_set); 
void devlink_port_type_ib_set(struct devlink_port *devlink_port,

			      struct ib_device *ibdev)

{

	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_IB, ibdev);

	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_IB, ibdev,

				false);

}

EXPORT_SYMBOL_GPL(devlink_port_type_ib_set);
@@ -10101,7 +10116,8 @@ EXPORT_SYMBOL_GPL(devlink_port_type_ib_set); 
 */

void devlink_port_type_clear(struct devlink_port *devlink_port)

{

	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_NOTSET, NULL);

	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_NOTSET, NULL,

				false);

}

EXPORT_SYMBOL_GPL(devlink_port_type_clear);