1 files changed, 343 insertions, 0 deletions
diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h
new file mode 100644
index 0000000000..16af1a7f80
--- /dev/null
+++ b/net/can/j1939/j1939-priv.h
@@ -0,0 +1,343 @@
+/* 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_TX_ACK,
+	J1939_ERRQUEUE_TX_SCHED,
+	J1939_ERRQUEUE_TX_ABORT,
+	J1939_ERRQUEUE_RX_RTS,
+	J1939_ERRQUEUE_RX_DPO,
+	J1939_ERRQUEUE_RX_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;
+	u32 rx_tskey;
+};
+
+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_ */