From d41c9dbd12745cfc1cb2946cd99016d83c2c5364 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Wed, 2 Nov 2022 17:02:02 +0100 Subject: 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: Jiri Pirko Signed-off-by: Jakub Kicinski --- net/core/devlink.c | 46 +++++++++++++++++++++++++++++++--------------- 1 file changed, 31 insertions(+), 15 deletions(-) (limited to 'net/core/devlink.c') diff --git a/net/core/devlink.c b/net/core/devlink.c index ff81a5a5087c..3387dfbb80c5 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -1278,7 +1278,8 @@ out: 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; @@ -1293,7 +1294,8 @@ static int devlink_nl_port_fill(struct sk_buff *msg, goto nla_put_failure; /* Hold rtnl lock while accessing port's netdev attributes. */ - rtnl_lock(); + if (!rtnl_held) + rtnl_lock(); spin_lock_bh(&devlink_port->type_lock); if (nla_put_u16(msg, DEVLINK_ATTR_PORT_TYPE, devlink_port->type)) goto nla_put_failure_type_locked; @@ -1321,7 +1323,8 @@ static int devlink_nl_port_fill(struct sk_buff *msg, goto nla_put_failure_type_locked; } spin_unlock_bh(&devlink_port->type_lock); - rtnl_unlock(); + if (!rtnl_held) + rtnl_unlock(); if (devlink_nl_port_attrs_put(msg, devlink_port)) goto nla_put_failure; if (devlink_nl_port_function_attrs_put(msg, devlink_port, extack)) @@ -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); - rtnl_unlock(); + 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); -- cgit