From ebc3197963fc42841b183d0280bd3f9f85f13c30 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 23 Jun 2022 04:34:32 +0000 Subject: ipmr: add rcu protection over (struct vif_device)->dev We will soon use RCU instead of rwlock in ipmr & ip6mr This preliminary patch adds proper rcu verbs to read/write (struct vif_device)->dev Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/mroute_base.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mroute_base.h b/include/linux/mroute_base.h index e05ee9f001ff..10d1e4fb4e9f 100644 --- a/include/linux/mroute_base.h +++ b/include/linux/mroute_base.h @@ -26,7 +26,7 @@ * @remote: Remote address for tunnels */ struct vif_device { - struct net_device *dev; + struct net_device __rcu *dev; netdevice_tracker dev_tracker; unsigned long bytes_in, bytes_out; unsigned long pkt_in, pkt_out; @@ -52,6 +52,7 @@ static inline int mr_call_vif_notifier(struct notifier_block *nb, unsigned short family, enum fib_event_type event_type, struct vif_device *vif, + struct net_device *vif_dev, unsigned short vif_index, u32 tb_id, struct netlink_ext_ack *extack) { @@ -60,7 +61,7 @@ static inline int mr_call_vif_notifier(struct notifier_block *nb, .family = family, .extack = extack, }, - .dev = vif->dev, + .dev = vif_dev, .vif_index = vif_index, .vif_flags = vif->flags, .tb_id = tb_id, @@ -73,6 +74,7 @@ static inline int mr_call_vif_notifiers(struct net *net, unsigned short family, enum fib_event_type event_type, struct vif_device *vif, + struct net_device *vif_dev, unsigned short vif_index, u32 tb_id, unsigned int *ipmr_seq) { @@ -80,7 +82,7 @@ static inline int mr_call_vif_notifiers(struct net *net, .info = { .family = family, }, - .dev = vif->dev, + .dev = vif_dev, .vif_index = vif_index, .vif_flags = vif->flags, .tb_id = tb_id, @@ -98,7 +100,8 @@ static inline int mr_call_vif_notifiers(struct net *net, #define MAXVIFS 32 #endif -#define VIF_EXISTS(_mrt, _idx) (!!((_mrt)->vif_table[_idx].dev)) +/* Note: This helper is deprecated. */ +#define VIF_EXISTS(_mrt, _idx) (!!rcu_access_pointer((_mrt)->vif_table[_idx].dev)) /* mfc_flags: * MFC_STATIC - the entry was added statically (not by a routing daemon) -- cgit v1.3-18-gd494 From 194366b28b8306b7a24596c57c09635ab2891252 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 23 Jun 2022 04:34:46 +0000 Subject: ipmr: adopt rcu_read_lock() in mr_dump() We no longer need to acquire mrt_lock() in mr_dump, using rcu_read_lock() is enough. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/mroute_base.h | 4 ++-- net/ipv4/ipmr.c | 2 +- net/ipv4/ipmr_base.c | 8 +++----- net/ipv6/ip6mr.c | 2 +- 4 files changed, 7 insertions(+), 9 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mroute_base.h b/include/linux/mroute_base.h index 10d1e4fb4e9f..9dd4bf157255 100644 --- a/include/linux/mroute_base.h +++ b/include/linux/mroute_base.h @@ -308,7 +308,7 @@ int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family, struct netlink_ext_ack *extack), struct mr_table *(*mr_iter)(struct net *net, struct mr_table *mrt), - rwlock_t *mrt_lock, struct netlink_ext_ack *extack); + struct netlink_ext_ack *extack); #else static inline void vif_device_init(struct vif_device *v, struct net_device *dev, @@ -363,7 +363,7 @@ static inline int mr_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack), struct mr_table *(*mr_iter)(struct net *net, struct mr_table *mrt), - rwlock_t *mrt_lock, struct netlink_ext_ack *extack) + struct netlink_ext_ack *extack) { return -EINVAL; } diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 69ccd3d7c655..38963b8de7af 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -3027,7 +3027,7 @@ static int ipmr_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return mr_dump(net, nb, RTNL_FAMILY_IPMR, ipmr_rules_dump, - ipmr_mr_table_iter, &mrt_lock, extack); + ipmr_mr_table_iter, extack); } static const struct fib_notifier_ops ipmr_notifier_ops_template = { diff --git a/net/ipv4/ipmr_base.c b/net/ipv4/ipmr_base.c index 59f62b938472..271dc03fc6db 100644 --- a/net/ipv4/ipmr_base.c +++ b/net/ipv4/ipmr_base.c @@ -399,7 +399,6 @@ int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family, struct netlink_ext_ack *extack), struct mr_table *(*mr_iter)(struct net *net, struct mr_table *mrt), - rwlock_t *mrt_lock, struct netlink_ext_ack *extack) { struct mr_table *mrt; @@ -416,10 +415,9 @@ int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family, int vifi; /* Notifiy on table VIF entries */ - read_lock(mrt_lock); + rcu_read_lock(); for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) { - vif_dev = rcu_dereference_check(v->dev, - lockdep_is_held(mrt_lock)); + vif_dev = rcu_dereference(v->dev); if (!vif_dev) continue; @@ -430,7 +428,7 @@ int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family, if (err) break; } - read_unlock(mrt_lock); + rcu_read_unlock(); if (err) return err; diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index 08ac177fe30c..f0a9bceb8e3c 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -1267,7 +1267,7 @@ static int ip6mr_dump(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { return mr_dump(net, nb, RTNL_FAMILY_IP6MR, ip6mr_rules_dump, - ip6mr_mr_table_iter, &mrt_lock, extack); + ip6mr_mr_table_iter, extack); } static struct notifier_block ip6_mr_notifier = { -- cgit v1.3-18-gd494