| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| |
| #ifndef __DSA_TAG_H |
| #define __DSA_TAG_H |
| |
| #include <linux/if_vlan.h> |
| #include <linux/list.h> |
| #include <linux/types.h> |
| #include <net/dsa.h> |
| |
| #include "port.h" |
| #include "slave.h" |
| |
| struct dsa_tag_driver { |
| const struct dsa_device_ops *ops; |
| struct list_head list; |
| struct module *owner; |
| }; |
| |
| extern struct packet_type dsa_pack_type; |
| |
| const struct dsa_device_ops *dsa_tag_driver_get_by_id(int tag_protocol); |
| const struct dsa_device_ops *dsa_tag_driver_get_by_name(const char *name); |
| void dsa_tag_driver_put(const struct dsa_device_ops *ops); |
| const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops); |
| |
| static inline int dsa_tag_protocol_overhead(const struct dsa_device_ops *ops) |
| { |
| return ops->needed_headroom + ops->needed_tailroom; |
| } |
| |
| static inline struct net_device *dsa_master_find_slave(struct net_device *dev, |
| int device, int port) |
| { |
| struct dsa_port *cpu_dp = dev->dsa_ptr; |
| struct dsa_switch_tree *dst = cpu_dp->dst; |
| struct dsa_port *dp; |
| |
| list_for_each_entry(dp, &dst->ports, list) |
| if (dp->ds->index == device && dp->index == port && |
| dp->type == DSA_PORT_TYPE_USER) |
| return dp->slave; |
| |
| return NULL; |
| } |
| |
| /* If under a bridge with vlan_filtering=0, make sure to send pvid-tagged |
| * frames as untagged, since the bridge will not untag them. |
| */ |
| static inline struct sk_buff *dsa_untag_bridge_pvid(struct sk_buff *skb) |
| { |
| struct dsa_port *dp = dsa_slave_to_port(skb->dev); |
| struct net_device *br = dsa_port_bridge_dev_get(dp); |
| struct net_device *dev = skb->dev; |
| struct net_device *upper_dev; |
| u16 vid, pvid, proto; |
| int err; |
| |
| if (!br || br_vlan_enabled(br)) |
| return skb; |
| |
| err = br_vlan_get_proto(br, &proto); |
| if (err) |
| return skb; |
| |
| /* Move VLAN tag from data to hwaccel */ |
| if (!skb_vlan_tag_present(skb) && skb->protocol == htons(proto)) { |
| skb = skb_vlan_untag(skb); |
| if (!skb) |
| return NULL; |
| } |
| |
| if (!skb_vlan_tag_present(skb)) |
| return skb; |
| |
| vid = skb_vlan_tag_get_id(skb); |
| |
| /* We already run under an RCU read-side critical section since |
| * we are called from netif_receive_skb_list_internal(). |
| */ |
| err = br_vlan_get_pvid_rcu(dev, &pvid); |
| if (err) |
| return skb; |
| |
| if (vid != pvid) |
| return skb; |
| |
| /* The sad part about attempting to untag from DSA is that we |
| * don't know, unless we check, if the skb will end up in |
| * the bridge's data path - br_allowed_ingress() - or not. |
| * For example, there might be an 8021q upper for the |
| * default_pvid of the bridge, which will steal VLAN-tagged traffic |
| * from the bridge's data path. This is a configuration that DSA |
| * supports because vlan_filtering is 0. In that case, we should |
| * definitely keep the tag, to make sure it keeps working. |
| */ |
| upper_dev = __vlan_find_dev_deep_rcu(br, htons(proto), vid); |
| if (upper_dev) |
| return skb; |
| |
| __vlan_hwaccel_clear_tag(skb); |
| |
| return skb; |
| } |
| |
| /* For switches without hardware support for DSA tagging to be able |
| * to support termination through the bridge. |
| */ |
| static inline struct net_device * |
| dsa_find_designated_bridge_port_by_vid(struct net_device *master, u16 vid) |
| { |
| struct dsa_port *cpu_dp = master->dsa_ptr; |
| struct dsa_switch_tree *dst = cpu_dp->dst; |
| struct bridge_vlan_info vinfo; |
| struct net_device *slave; |
| struct dsa_port *dp; |
| int err; |
| |
| list_for_each_entry(dp, &dst->ports, list) { |
| if (dp->type != DSA_PORT_TYPE_USER) |
| continue; |
| |
| if (!dp->bridge) |
| continue; |
| |
| if (dp->stp_state != BR_STATE_LEARNING && |
| dp->stp_state != BR_STATE_FORWARDING) |
| continue; |
| |
| /* Since the bridge might learn this packet, keep the CPU port |
| * affinity with the port that will be used for the reply on |
| * xmit. |
| */ |
| if (dp->cpu_dp != cpu_dp) |
| continue; |
| |
| slave = dp->slave; |
| |
| err = br_vlan_get_info_rcu(slave, vid, &vinfo); |
| if (err) |
| continue; |
| |
| return slave; |
| } |
| |
| return NULL; |
| } |
| |
| /* If the ingress port offloads the bridge, we mark the frame as autonomously |
| * forwarded by hardware, so the software bridge doesn't forward in twice, back |
| * to us, because we already did. However, if we're in fallback mode and we do |
| * software bridging, we are not offloading it, therefore the dp->bridge |
| * pointer is not populated, and flooding needs to be done by software (we are |
| * effectively operating in standalone ports mode). |
| */ |
| static inline void dsa_default_offload_fwd_mark(struct sk_buff *skb) |
| { |
| struct dsa_port *dp = dsa_slave_to_port(skb->dev); |
| |
| skb->offload_fwd_mark = !!(dp->bridge); |
| } |
| |
| /* Helper for removing DSA header tags from packets in the RX path. |
| * Must not be called before skb_pull(len). |
| * skb->data |
| * | |
| * v |
| * | | | | | | | | | | | | | | | | | | | |
| * +-----------------------+-----------------------+---------------+-------+ |
| * | Destination MAC | Source MAC | DSA header | EType | |
| * +-----------------------+-----------------------+---------------+-------+ |
| * | | |
| * <----- len -----> <----- len -----> |
| * | |
| * >>>>>>> v |
| * >>>>>>> | | | | | | | | | | | | | | | |
| * >>>>>>> +-----------------------+-----------------------+-------+ |
| * >>>>>>> | Destination MAC | Source MAC | EType | |
| * +-----------------------+-----------------------+-------+ |
| * ^ |
| * | |
| * skb->data |
| */ |
| static inline void dsa_strip_etype_header(struct sk_buff *skb, int len) |
| { |
| memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - len, 2 * ETH_ALEN); |
| } |
| |
| /* Helper for creating space for DSA header tags in TX path packets. |
| * Must not be called before skb_push(len). |
| * |
| * Before: |
| * |
| * <<<<<<< | | | | | | | | | | | | | | | |
| * ^ <<<<<<< +-----------------------+-----------------------+-------+ |
| * | <<<<<<< | Destination MAC | Source MAC | EType | |
| * | +-----------------------+-----------------------+-------+ |
| * <----- len -----> |
| * | |
| * | |
| * skb->data |
| * |
| * After: |
| * |
| * | | | | | | | | | | | | | | | | | | | |
| * +-----------------------+-----------------------+---------------+-------+ |
| * | Destination MAC | Source MAC | DSA header | EType | |
| * +-----------------------+-----------------------+---------------+-------+ |
| * ^ | | |
| * | <----- len -----> |
| * skb->data |
| */ |
| static inline void dsa_alloc_etype_header(struct sk_buff *skb, int len) |
| { |
| memmove(skb->data, skb->data + len, 2 * ETH_ALEN); |
| } |
| |
| /* On RX, eth_type_trans() on the DSA master pulls ETH_HLEN bytes starting from |
| * skb_mac_header(skb), which leaves skb->data pointing at the first byte after |
| * what the DSA master perceives as the EtherType (the beginning of the L3 |
| * protocol). Since DSA EtherType header taggers treat the EtherType as part of |
| * the DSA tag itself, and the EtherType is 2 bytes in length, the DSA header |
| * is located 2 bytes behind skb->data. Note that EtherType in this context |
| * means the first 2 bytes of the DSA header, not the encapsulated EtherType |
| * that will become visible after the DSA header is stripped. |
| */ |
| static inline void *dsa_etype_header_pos_rx(struct sk_buff *skb) |
| { |
| return skb->data - 2; |
| } |
| |
| /* On TX, skb->data points to the MAC header, which means that EtherType |
| * header taggers start exactly where the EtherType is (the EtherType is |
| * treated as part of the DSA header). |
| */ |
| static inline void *dsa_etype_header_pos_tx(struct sk_buff *skb) |
| { |
| return skb->data + 2 * ETH_ALEN; |
| } |
| |
| /* Create 2 modaliases per tagging protocol, one to auto-load the module |
| * given the ID reported by get_tag_protocol(), and the other by name. |
| */ |
| #define DSA_TAG_DRIVER_ALIAS "dsa_tag:" |
| #define MODULE_ALIAS_DSA_TAG_DRIVER(__proto, __name) \ |
| MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS __name); \ |
| MODULE_ALIAS(DSA_TAG_DRIVER_ALIAS "id-" \ |
| __stringify(__proto##_VALUE)) |
| |
| void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[], |
| unsigned int count, |
| struct module *owner); |
| void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[], |
| unsigned int count); |
| |
| #define dsa_tag_driver_module_drivers(__dsa_tag_drivers_array, __count) \ |
| static int __init dsa_tag_driver_module_init(void) \ |
| { \ |
| dsa_tag_drivers_register(__dsa_tag_drivers_array, __count, \ |
| THIS_MODULE); \ |
| return 0; \ |
| } \ |
| module_init(dsa_tag_driver_module_init); \ |
| \ |
| static void __exit dsa_tag_driver_module_exit(void) \ |
| { \ |
| dsa_tag_drivers_unregister(__dsa_tag_drivers_array, __count); \ |
| } \ |
| module_exit(dsa_tag_driver_module_exit) |
| |
| /** |
| * module_dsa_tag_drivers() - Helper macro for registering DSA tag |
| * drivers |
| * @__ops_array: Array of tag driver structures |
| * |
| * Helper macro for DSA tag drivers which do not do anything special |
| * in module init/exit. Each module may only use this macro once, and |
| * calling it replaces module_init() and module_exit(). |
| */ |
| #define module_dsa_tag_drivers(__ops_array) \ |
| dsa_tag_driver_module_drivers(__ops_array, ARRAY_SIZE(__ops_array)) |
| |
| #define DSA_TAG_DRIVER_NAME(__ops) dsa_tag_driver ## _ ## __ops |
| |
| /* Create a static structure we can build a linked list of dsa_tag |
| * drivers |
| */ |
| #define DSA_TAG_DRIVER(__ops) \ |
| static struct dsa_tag_driver DSA_TAG_DRIVER_NAME(__ops) = { \ |
| .ops = &__ops, \ |
| } |
| |
| /** |
| * module_dsa_tag_driver() - Helper macro for registering a single DSA tag |
| * driver |
| * @__ops: Single tag driver structures |
| * |
| * Helper macro for DSA tag drivers which do not do anything special |
| * in module init/exit. Each module may only use this macro once, and |
| * calling it replaces module_init() and module_exit(). |
| */ |
| #define module_dsa_tag_driver(__ops) \ |
| DSA_TAG_DRIVER(__ops); \ |
| \ |
| static struct dsa_tag_driver *dsa_tag_driver_array[] = { \ |
| &DSA_TAG_DRIVER_NAME(__ops) \ |
| }; \ |
| module_dsa_tag_drivers(dsa_tag_driver_array) |
| |
| #endif |
