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Diffstat (limited to 'net/can/j1939/j1939-priv.h')
| -rw-r--r-- | net/can/j1939/j1939-priv.h | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h new file mode 100644 index 000000000..cea712fb2 --- /dev/null +++ b/net/can/j1939/j1939-priv.h @@ -0,0 +1,339 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#ifndef _J1939_PRIV_H_ +#define _J1939_PRIV_H_ + +#include <linux/can/j1939.h> +#include <net/sock.h> + +/* Timeout to receive the abort signal over loop back. In case CAN + * bus is open, the timeout should be triggered. + */ +#define J1939_XTP_ABORT_TIMEOUT_MS 500 +#define J1939_SIMPLE_ECHO_TIMEOUT_MS (10 * 1000) + +struct j1939_session; +enum j1939_sk_errqueue_type { + J1939_ERRQUEUE_ACK, + J1939_ERRQUEUE_SCHED, + J1939_ERRQUEUE_ABORT, +}; + +/* j1939 devices */ +struct j1939_ecu { + struct list_head list; + name_t name; + u8 addr; + + /* indicates that this ecu successfully claimed @sa as its address */ + struct hrtimer ac_timer; + struct kref kref; + struct j1939_priv *priv; + + /* count users, to help transport protocol decide for interaction */ + int nusers; +}; + +struct j1939_priv { + struct list_head ecus; + /* local list entry in priv + * These allow irq (& softirq) context lookups on j1939 devices + * This approach (separate lists) is done as the other 2 alternatives + * are not easier or even wrong + * 1) using the pure kobject methods involves mutexes, which are not + * allowed in irq context. + * 2) duplicating data structures would require a lot of synchronization + * code + * usage: + */ + + /* segments need a lock to protect the above list */ + rwlock_t lock; + + struct net_device *ndev; + + /* list of 256 ecu ptrs, that cache the claimed addresses. + * also protected by the above lock + */ + struct j1939_addr_ent { + struct j1939_ecu *ecu; + /* count users, to help transport protocol */ + int nusers; + } ents[256]; + + struct kref kref; + + /* List of active sessions to prevent start of conflicting + * one. + * + * Do not start two sessions of same type, addresses and + * direction. + */ + struct list_head active_session_list; + + /* protects active_session_list */ + spinlock_t active_session_list_lock; + + unsigned int tp_max_packet_size; + + /* lock for j1939_socks list */ + spinlock_t j1939_socks_lock; + struct list_head j1939_socks; + + struct kref rx_kref; +}; + +void j1939_ecu_put(struct j1939_ecu *ecu); + +/* keep the cache of what is local */ +int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa); +void j1939_local_ecu_put(struct j1939_priv *priv, name_t name, u8 sa); + +static inline bool j1939_address_is_unicast(u8 addr) +{ + return addr <= J1939_MAX_UNICAST_ADDR; +} + +static inline bool j1939_address_is_idle(u8 addr) +{ + return addr == J1939_IDLE_ADDR; +} + +static inline bool j1939_address_is_valid(u8 addr) +{ + return addr != J1939_NO_ADDR; +} + +static inline bool j1939_pgn_is_pdu1(pgn_t pgn) +{ + /* ignore dp & res bits for this */ + return (pgn & 0xff00) < 0xf000; +} + +/* utility to correctly unmap an ECU */ +void j1939_ecu_unmap_locked(struct j1939_ecu *ecu); +void j1939_ecu_unmap(struct j1939_ecu *ecu); + +u8 j1939_name_to_addr(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_find_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr(struct j1939_priv *priv, u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_name(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_get_by_name_locked(struct j1939_priv *priv, + name_t name); + +enum j1939_transfer_type { + J1939_TP, + J1939_ETP, + J1939_SIMPLE, +}; + +struct j1939_addr { + name_t src_name; + name_t dst_name; + pgn_t pgn; + + u8 sa; + u8 da; + + u8 type; +}; + +/* control buffer of the sk_buff */ +struct j1939_sk_buff_cb { + /* Offset in bytes within one ETP session */ + u32 offset; + + /* for tx, MSG_SYN will be used to sync on sockets */ + u32 msg_flags; + u32 tskey; + + struct j1939_addr addr; + + /* Flags for quick lookups during skb processing. + * These are set in the receive path only. + */ +#define J1939_ECU_LOCAL_SRC BIT(0) +#define J1939_ECU_LOCAL_DST BIT(1) + u8 flags; + + priority_t priority; +}; + +static inline +struct j1939_sk_buff_cb *j1939_skb_to_cb(const struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct j1939_sk_buff_cb) > sizeof(skb->cb)); + + return (struct j1939_sk_buff_cb *)skb->cb; +} + +int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb); +bool j1939_sk_recv_match(struct j1939_priv *priv, + struct j1939_sk_buff_cb *skcb); +void j1939_sk_send_loop_abort(struct sock *sk, int err); +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type); +void j1939_sk_queue_activate_next(struct j1939_session *session); + +/* stack entries */ +struct j1939_session *j1939_tp_send(struct j1939_priv *priv, + struct sk_buff *skb, size_t size); +int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb); +int j1939_ac_fixup(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_ac_recv(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb); + +/* network management */ +struct j1939_ecu *j1939_ecu_create_locked(struct j1939_priv *priv, name_t name); + +void j1939_ecu_timer_start(struct j1939_ecu *ecu); +void j1939_ecu_timer_cancel(struct j1939_ecu *ecu); +void j1939_ecu_unmap_all(struct j1939_priv *priv); + +struct j1939_priv *j1939_netdev_start(struct net_device *ndev); +void j1939_netdev_stop(struct j1939_priv *priv); + +void j1939_priv_put(struct j1939_priv *priv); +void j1939_priv_get(struct j1939_priv *priv); + +/* notify/alert all j1939 sockets bound to ifindex */ +void j1939_sk_netdev_event_netdown(struct j1939_priv *priv); +int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk); +void j1939_tp_init(struct j1939_priv *priv); + +/* decrement pending skb for a j1939 socket */ +void j1939_sock_pending_del(struct sock *sk); + +enum j1939_session_state { + J1939_SESSION_NEW, + J1939_SESSION_ACTIVE, + /* waiting for abort signal on the bus */ + J1939_SESSION_WAITING_ABORT, + J1939_SESSION_ACTIVE_MAX, + J1939_SESSION_DONE, +}; + +struct j1939_session { + struct j1939_priv *priv; + struct list_head active_session_list_entry; + struct list_head sk_session_queue_entry; + struct kref kref; + struct sock *sk; + + /* ifindex, src, dst, pgn define the session block + * the are _never_ modified after insertion in the list + * this decreases locking problems a _lot_ + */ + struct j1939_sk_buff_cb skcb; + struct sk_buff_head skb_queue; + + /* all tx related stuff (last_txcmd, pkt.tx) + * is protected (modified only) with the txtimer hrtimer + * 'total' & 'block' are never changed, + * last_cmd, last & block are protected by ->lock + * this means that the tx may run after cts is received that should + * have stopped tx, but this time discrepancy is never avoided anyhow + */ + u8 last_cmd, last_txcmd; + bool transmission; + bool extd; + /* Total message size, number of bytes */ + unsigned int total_message_size; + /* Total number of bytes queue from socket to the session */ + unsigned int total_queued_size; + unsigned int tx_retry; + + int err; + u32 tskey; + enum j1939_session_state state; + + /* Packets counters for a (extended) transfer session. The packet is + * maximal of 7 bytes. + */ + struct { + /* total - total number of packets for this session */ + unsigned int total; + /* last - last packet of a transfer block after which + * responder should send ETP.CM_CTS and originator + * ETP.CM_DPO + */ + unsigned int last; + /* tx - number of packets send by originator node. + * this counter can be set back if responder node + * didn't received all packets send by originator. + */ + unsigned int tx; + unsigned int tx_acked; + /* rx - number of packets received */ + unsigned int rx; + /* block - amount of packets expected in one block */ + unsigned int block; + /* dpo - ETP.CM_DPO, Data Packet Offset */ + unsigned int dpo; + } pkt; + struct hrtimer txtimer, rxtimer; +}; + +struct j1939_sock { + struct sock sk; /* must be first to skip with memset */ + struct j1939_priv *priv; + struct list_head list; + +#define J1939_SOCK_BOUND BIT(0) +#define J1939_SOCK_CONNECTED BIT(1) +#define J1939_SOCK_PROMISC BIT(2) +#define J1939_SOCK_ERRQUEUE BIT(3) + int state; + + int ifindex; + struct j1939_addr addr; + struct j1939_filter *filters; + int nfilters; + pgn_t pgn_rx_filter; + + /* j1939 may emit equal PGN (!= equal CAN-id's) out of order + * when transport protocol comes in. + * To allow emitting in order, keep a 'pending' nr. of packets + */ + atomic_t skb_pending; + wait_queue_head_t waitq; + + /* lock for the sk_session_queue list */ + spinlock_t sk_session_queue_lock; + struct list_head sk_session_queue; +}; + +static inline struct j1939_sock *j1939_sk(const struct sock *sk) +{ + return container_of(sk, struct j1939_sock, sk); +} + +void j1939_session_get(struct j1939_session *session); +void j1939_session_put(struct j1939_session *session); +void j1939_session_skb_queue(struct j1939_session *session, + struct sk_buff *skb); +int j1939_session_activate(struct j1939_session *session); +void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec); +void j1939_session_timers_cancel(struct j1939_session *session); + +#define J1939_MIN_TP_PACKET_SIZE 9 +#define J1939_MAX_TP_PACKET_SIZE (7 * 0xff) +#define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff) + +#define J1939_REGULAR 0 +#define J1939_EXTENDED 1 + +/* CAN protocol */ +extern const struct can_proto j1939_can_proto; + +#endif /* _J1939_PRIV_H_ */ |