From d3eed0e57d5d1bcbf1bd60f83a4adfe7d7b8dd9c Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 6 Dec 2021 18:57:56 +0200 Subject: net: dsa: keep the bridge_dev and bridge_num as part of the same structure MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The main desire behind this is to provide coherent bridge information to the fast path without locking. For example, right now we set dp->bridge_dev and dp->bridge_num from separate code paths, it is theoretically possible for a packet transmission to read these two port properties consecutively and find a bridge number which does not correspond with the bridge device. Another desire is to start passing more complex bridge information to dsa_switch_ops functions. For example, with FDB isolation, it is expected that drivers will need to be passed the bridge which requested an FDB/MDB entry to be offloaded, and along with that bridge_dev, the associated bridge_num should be passed too, in case the driver might want to implement an isolation scheme based on that number. We already pass the {bridge_dev, bridge_num} pair to the TX forwarding offload switch API, however we'd like to remove that and squash it into the basic bridge join/leave API. So that means we need to pass this pair to the bridge join/leave API. During dsa_port_bridge_leave, first we unset dp->bridge_dev, then we call the driver's .port_bridge_leave with what used to be our dp->bridge_dev, but provided as an argument. When bridge_dev and bridge_num get folded into a single structure, we need to preserve this behavior in dsa_port_bridge_leave: we need a copy of what used to be in dp->bridge. Switch drivers check bridge membership by comparing dp->bridge_dev with the provided bridge_dev, but now, if we provide the struct dsa_bridge as a pointer, they cannot keep comparing dp->bridge to the provided pointer, since this only points to an on-stack copy. To make this obvious and prevent driver writers from forgetting and doing stupid things, in this new API, the struct dsa_bridge is provided as a full structure (not very large, contains an int and a pointer) instead of a pointer. An explicit comparison function needs to be used to determine bridge membership: dsa_port_offloads_bridge(). Signed-off-by: Vladimir Oltean Reviewed-by: Alvin Šipraga Signed-off-by: Jakub Kicinski --- include/linux/dsa/8021q.h | 7 +++---- include/net/dsa.h | 34 +++++++++++++++++++++------------- 2 files changed, 24 insertions(+), 17 deletions(-) (limited to 'include') diff --git a/include/linux/dsa/8021q.h b/include/linux/dsa/8021q.h index 0af4371fbebb..939a1beaddf7 100644 --- a/include/linux/dsa/8021q.h +++ b/include/linux/dsa/8021q.h @@ -7,6 +7,7 @@ #include #include +#include struct dsa_switch; struct dsa_port; @@ -37,12 +38,10 @@ struct sk_buff *dsa_8021q_xmit(struct sk_buff *skb, struct net_device *netdev, void dsa_8021q_rcv(struct sk_buff *skb, int *source_port, int *switch_id); int dsa_tag_8021q_bridge_tx_fwd_offload(struct dsa_switch *ds, int port, - struct net_device *br, - unsigned int bridge_num); + struct dsa_bridge bridge); void dsa_tag_8021q_bridge_tx_fwd_unoffload(struct dsa_switch *ds, int port, - struct net_device *br, - unsigned int bridge_num); + struct dsa_bridge bridge); u16 dsa_8021q_bridge_tx_fwd_offload_vid(unsigned int bridge_num); diff --git a/include/net/dsa.h b/include/net/dsa.h index 899e13d56fc2..b9789c0cd5e3 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -219,6 +219,11 @@ struct dsa_mall_tc_entry { }; }; +struct dsa_bridge { + struct net_device *dev; + unsigned int num; + refcount_t refcount; +}; struct dsa_port { /* A CPU port is physically connected to a master device. @@ -256,8 +261,7 @@ struct dsa_port { /* Managed by DSA on user ports and by drivers on CPU and DSA ports */ bool learning; u8 stp_state; - struct net_device *bridge_dev; - unsigned int bridge_num; + struct dsa_bridge *bridge; struct devlink_port devlink_port; bool devlink_port_setup; struct phylink *pl; @@ -588,7 +592,7 @@ static inline bool dsa_port_is_vlan_filtering(const struct dsa_port *dp) static inline struct net_device *dsa_port_to_bridge_port(const struct dsa_port *dp) { - if (!dp->bridge_dev) + if (!dp->bridge) return NULL; if (dp->lag_dev) @@ -602,12 +606,12 @@ struct net_device *dsa_port_to_bridge_port(const struct dsa_port *dp) static inline struct net_device * dsa_port_bridge_dev_get(const struct dsa_port *dp) { - return dp->bridge_dev; + return dp->bridge ? dp->bridge->dev : NULL; } static inline unsigned int dsa_port_bridge_num_get(struct dsa_port *dp) { - return dp->bridge_num; + return dp->bridge ? dp->bridge->num : 0; } static inline bool dsa_port_bridge_same(const struct dsa_port *a, @@ -636,6 +640,12 @@ dsa_port_offloads_bridge_dev(struct dsa_port *dp, return dsa_port_bridge_dev_get(dp) == bridge_dev; } +static inline bool dsa_port_offloads_bridge(struct dsa_port *dp, + const struct dsa_bridge *bridge) +{ + return dsa_port_bridge_dev_get(dp) == bridge->dev; +} + /* Returns true if any port of this tree offloads the given net_device */ static inline bool dsa_tree_offloads_bridge_port(struct dsa_switch_tree *dst, const struct net_device *dev) @@ -812,17 +822,15 @@ struct dsa_switch_ops { */ int (*set_ageing_time)(struct dsa_switch *ds, unsigned int msecs); int (*port_bridge_join)(struct dsa_switch *ds, int port, - struct net_device *bridge); + struct dsa_bridge bridge); void (*port_bridge_leave)(struct dsa_switch *ds, int port, - struct net_device *bridge); + struct dsa_bridge bridge); /* Called right after .port_bridge_join() */ int (*port_bridge_tx_fwd_offload)(struct dsa_switch *ds, int port, - struct net_device *bridge, - unsigned int bridge_num); + struct dsa_bridge bridge); /* Called right before .port_bridge_leave() */ void (*port_bridge_tx_fwd_unoffload)(struct dsa_switch *ds, int port, - struct net_device *bridge, - unsigned int bridge_num); + struct dsa_bridge bridge); void (*port_stp_state_set)(struct dsa_switch *ds, int port, u8 state); void (*port_fast_age)(struct dsa_switch *ds, int port); @@ -894,10 +902,10 @@ struct dsa_switch_ops { */ int (*crosschip_bridge_join)(struct dsa_switch *ds, int tree_index, int sw_index, int port, - struct net_device *br); + struct dsa_bridge bridge); void (*crosschip_bridge_leave)(struct dsa_switch *ds, int tree_index, int sw_index, int port, - struct net_device *br); + struct dsa_bridge bridge); int (*crosschip_lag_change)(struct dsa_switch *ds, int sw_index, int port); int (*crosschip_lag_join)(struct dsa_switch *ds, int sw_index, -- cgit v1.2.3