From 1158958a218bb55d1c358200d7f82808d11bf929 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 13 Sep 2019 18:28:39 +0300 Subject: net: sched: extend flow_action_entry with destructor Generalize flow_action_entry cleanup by extending the structure with pointer to destructor function. Set the destructor in tc_setup_flow_action(). Refactor tc_cleanup_flow_action() to call entry->destructor() instead of using switch that dispatches by entry->id and manually executes cleanup. This refactoring is necessary for following patches in this series that require destructor to use tc_action->ops callbacks that can't be easily obtained in tc_cleanup_flow_action(). Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/flow_offload.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h index fc881875f856..86c567f531f3 100644 --- a/include/net/flow_offload.h +++ b/include/net/flow_offload.h @@ -154,8 +154,12 @@ enum flow_action_mangle_base { FLOW_ACT_MANGLE_HDR_TYPE_UDP, }; +typedef void (*action_destr)(void *priv); + struct flow_action_entry { enum flow_action_id id; + action_destr destructor; + void *destructor_priv; union { u32 chain_index; /* FLOW_ACTION_GOTO */ struct net_device *dev; /* FLOW_ACTION_REDIRECT */ @@ -170,7 +174,7 @@ struct flow_action_entry { u32 mask; u32 val; } mangle; - const struct ip_tunnel_info *tunnel; /* FLOW_ACTION_TUNNEL_ENCAP */ + struct ip_tunnel_info *tunnel; /* FLOW_ACTION_TUNNEL_ENCAP */ u32 csum_flags; /* FLOW_ACTION_CSUM */ u32 mark; /* FLOW_ACTION_MARK */ u16 ptype; /* FLOW_ACTION_PTYPE */ -- cgit v1.2.3 From 4a5da47d5cb6aba3c26a5cc0dddfb2d577e851e9 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 13 Sep 2019 18:28:40 +0300 Subject: net: sched: take reference to psample group in flow_action infra With recent patch set that removed rtnl lock dependency from cls hardware offload API rtnl lock is only taken when reading action data and can be released after action-specific data is parsed into intermediate representation. However, sample action psample group is passed by pointer without obtaining reference to it first, which makes it possible to concurrently overwrite the action and deallocate object pointed by psample_group pointer after rtnl lock is released but before driver finished using the pointer. To prevent such race condition, obtain reference to psample group while it is used by flow_action infra. Extend psample API with function psample_group_take() that increments psample group reference counter. Extend struct tc_action_ops with new get_psample_group() API. Implement the API for action sample using psample_group_take() and already existing psample_group_put() as a destructor. Use it in tc_setup_flow_action() to take reference to psample group pointed to by entry->sample.psample_group and release it in tc_cleanup_flow_action(). Disable bh when taking psample_groups_lock. The lock is now taken while holding action tcf_lock that is used by data path and requires bh to be disabled, so doing the same for psample_groups_lock is necessary to preserve SOFTIRQ-irq-safety. Fixes: 918190f50eb6 ("net: sched: flower: don't take rtnl lock for cls hw offloads API") Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 5 +++++ include/net/psample.h | 1 + include/net/tc_act/tc_sample.h | 6 ------ 3 files changed, 6 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 3a1a72990fce..4be8b0daedf0 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -78,6 +78,8 @@ static inline void tcf_tm_dump(struct tcf_t *dtm, const struct tcf_t *stm) #define ACT_P_CREATED 1 #define ACT_P_DELETED 1 +typedef void (*tc_action_priv_destructor)(void *priv); + struct tc_action_ops { struct list_head head; char kind[IFNAMSIZ]; @@ -101,6 +103,9 @@ struct tc_action_ops { size_t (*get_fill_size)(const struct tc_action *act); struct net_device *(*get_dev)(const struct tc_action *a); void (*put_dev)(struct net_device *dev); + struct psample_group * + (*get_psample_group)(const struct tc_action *a, + tc_action_priv_destructor *destructor); }; struct tc_action_net { diff --git a/include/net/psample.h b/include/net/psample.h index 6b578ce69cd8..68ae16bb0a4a 100644 --- a/include/net/psample.h +++ b/include/net/psample.h @@ -15,6 +15,7 @@ struct psample_group { }; struct psample_group *psample_group_get(struct net *net, u32 group_num); +void psample_group_take(struct psample_group *group); void psample_group_put(struct psample_group *group); #if IS_ENABLED(CONFIG_PSAMPLE) diff --git a/include/net/tc_act/tc_sample.h b/include/net/tc_act/tc_sample.h index b4fce0fae645..b5d76305e854 100644 --- a/include/net/tc_act/tc_sample.h +++ b/include/net/tc_act/tc_sample.h @@ -41,10 +41,4 @@ static inline int tcf_sample_trunc_size(const struct tc_action *a) return to_sample(a)->trunc_size; } -static inline struct psample_group * -tcf_sample_psample_group(const struct tc_action *a) -{ - return rcu_dereference_rtnl(to_sample(a)->psample_group); -} - #endif /* __NET_TC_SAMPLE_H */ -- cgit v1.2.3 From 470d5060e6b3b8fae47d944601855e9ece7a2470 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 13 Sep 2019 18:28:41 +0300 Subject: net: sched: use get_dev() action API in flow_action infra When filling in hardware intermediate representation tc_setup_flow_action() directly obtains, checks and takes reference to dev used by mirred action, instead of using act->ops->get_dev() API created specifically for this purpose. In order to remove code duplication, refactor flow_action infra to use action API when obtaining mirred action target dev. Extend get_dev() with additional argument that is used to provide dev destructor to the user. Fixes: 5a6ff4b13d59 ("net: sched: take reference to action dev before calling offloads") Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 4be8b0daedf0..b18c699681ca 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -101,8 +101,8 @@ struct tc_action_ops { struct netlink_ext_ack *); void (*stats_update)(struct tc_action *, u64, u32, u64, bool); size_t (*get_fill_size)(const struct tc_action *act); - struct net_device *(*get_dev)(const struct tc_action *a); - void (*put_dev)(struct net_device *dev); + struct net_device *(*get_dev)(const struct tc_action *a, + tc_action_priv_destructor *destructor); struct psample_group * (*get_psample_group)(const struct tc_action *a, tc_action_priv_destructor *destructor); -- cgit v1.2.3