Merge tag 'linux-can-next-for-5.18-20220310' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2022-03-10

The first 3 patches are by Oliver Hartkopp, target the CAN ISOTP
protocol and update the CAN frame sending behavior, and increases the
max PDU size to 64 kByte.

The next 2 patches are also by Oliver Hartkopp and update the virtual
VXCAN driver so that CAN frames send into the peer name space show up
as RX'ed CAN frames.

Vincent Mailhol contributes a patch for the etas_es58x driver to fix a
false positive dereference uninitialized variable warning.

2 patches by Ulrich Hecht add r8a779a0 SoC support to the rcar_canfd
driver.

The remaining 21 patches target the gs_usb driver and are by Peter
Fink, Ben Evans, Eric Evenchick and me. This series cleans up the
gs-usb driver, documents some bits of the USB ABI used by the widely
used open source firmware candleLight, adds support for up to 3 CAN
interfaces per USB device, adds CAN-FD support, adds quirks for some
hardware and software workarounds and finally adds support for 2 new
devices.

* tag 'linux-can-next-for-5.18-20220310' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next: (29 commits)
  can: gs_usb: add VID/PID for ABE CAN Debugger devices
  can: gs_usb: add VID/PID for CES CANext FD devices
  can: gs_usb: add extended bt_const feature
  can: gs_usb: activate quirks for CANtact Pro unconditionally
  can: gs_usb: add quirk for CANtact Pro overlapping GS_USB_BREQ value
  can: gs_usb: add usb quirk for NXP LPC546xx controllers
  can: gs_usb: add CAN-FD support
  can: gs_usb: use union and FLEX_ARRAY for data in struct gs_host_frame
  can: gs_usb: support up to 3 channels per device
  can: gs_usb: gs_usb_probe(): introduce udev and make use of it
  can: gs_usb: document the PAD_PKTS_TO_MAX_PKT_SIZE feature
  can: gs_usb: document the USER_ID feature
  can: gs_usb: update GS_CAN_FEATURE_IDENTIFY documentation
  can: gs_usb: add HW timestamp mode bit
  can: gs_usb: gs_make_candev(): call SET_NETDEV_DEV() after handling all bt_const->feature
  can: gs_usb: rewrap usb_control_msg() and usb_fill_bulk_urb()
  can: gs_usb: rewrap error messages
  can: gs_usb: GS_CAN_FLAG_OVERFLOW: make use of BIT()
  can: gs_usb: sort include files alphabetically
  can: gs_usb: fix checkpatch warning
  ...
====================

Link: https://lore.kernel.org/r/20220310142903.341658-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 152 insertions, 83 deletions

diff --git a/net/can/isotp.c b/net/can/isotp.c
index d2a430b6a13b..d4c0b4704987 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -14,7 +14,6 @@
  * - use CAN_ISOTP_WAIT_TX_DONE flag to block the caller until the PDU is sent
  * - as we have static buffers the check whether the PDU fits into the buffer
  *   is done at FF reception time (no support for sending 'wait frames')
- * - take care of the tx-queue-len as traffic shaping is still on the TODO list
  *
  * Copyright (c) 2020 Volkswagen Group Electronic Research
  * All rights reserved.
@@ -87,9 +86,9 @@ MODULE_ALIAS("can-proto-6");
 /* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can
  * take full 32 bit values (4 Gbyte). We would need some good concept to handle
  * this between user space and kernel space. For now increase the static buffer
- * to something about 8 kbyte to be able to test this new functionality.
+ * to something about 64 kbyte to be able to test this new functionality.
  */
-#define MAX_MSG_LENGTH 8200
+#define MAX_MSG_LENGTH 66000
 
 /* N_PCI type values in bits 7-4 of N_PCI bytes */
 #define N_PCI_SF 0x00	/* single frame */
@@ -141,8 +140,10 @@ struct isotp_sock {
 	struct can_isotp_options opt;
 	struct can_isotp_fc_options rxfc, txfc;
 	struct can_isotp_ll_options ll;
+	u32 frame_txtime;
 	u32 force_tx_stmin;
 	u32 force_rx_stmin;
+	u32 cfecho; /* consecutive frame echo tag */
 	struct tpcon rx, tx;
 	struct list_head notifier;
 	wait_queue_head_t wait;
@@ -360,7 +361,7 @@ static int isotp_rcv_fc(struct isotp_sock *so, struct canfd_frame *cf, int ae)
 
 		so->tx_gap = ktime_set(0, 0);
 		/* add transmission time for CAN frame N_As */
-		so->tx_gap = ktime_add_ns(so->tx_gap, so->opt.frame_txtime);
+		so->tx_gap = ktime_add_ns(so->tx_gap, so->frame_txtime);
 		/* add waiting time for consecutive frames N_Cs */
 		if (so->opt.flags & CAN_ISOTP_FORCE_TXSTMIN)
 			so->tx_gap = ktime_add_ns(so->tx_gap,
@@ -712,6 +713,63 @@ static void isotp_fill_dataframe(struct canfd_frame *cf, struct isotp_sock *so,
 		cf->data[0] = so->opt.ext_address;
 }
 
+static void isotp_send_cframe(struct isotp_sock *so)
+{
+	struct sock *sk = &so->sk;
+	struct sk_buff *skb;
+	struct net_device *dev;
+	struct canfd_frame *cf;
+	int can_send_ret;
+	int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0;
+
+	dev = dev_get_by_index(sock_net(sk), so->ifindex);
+	if (!dev)
+		return;
+
+	skb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), GFP_ATOMIC);
+	if (!skb) {
+		dev_put(dev);
+		return;
+	}
+
+	can_skb_reserve(skb);
+	can_skb_prv(skb)->ifindex = dev->ifindex;
+	can_skb_prv(skb)->skbcnt = 0;
+
+	cf = (struct canfd_frame *)skb->data;
+	skb_put_zero(skb, so->ll.mtu);
+
+	/* create consecutive frame */
+	isotp_fill_dataframe(cf, so, ae, 0);
+
+	/* place consecutive frame N_PCI in appropriate index */
+	cf->data[ae] = N_PCI_CF | so->tx.sn++;
+	so->tx.sn %= 16;
+	so->tx.bs++;
+
+	cf->flags = so->ll.tx_flags;
+
+	skb->dev = dev;
+	can_skb_set_owner(skb, sk);
+
+	/* cfecho should have been zero'ed by init/isotp_rcv_echo() */
+	if (so->cfecho)
+		pr_notice_once("can-isotp: cfecho is %08X != 0\n", so->cfecho);
+
+	/* set consecutive frame echo tag */
+	so->cfecho = *(u32 *)cf->data;
+
+	/* send frame with local echo enabled */
+	can_send_ret = can_send(skb, 1);
+	if (can_send_ret) {
+		pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
+			       __func__, ERR_PTR(can_send_ret));
+		if (can_send_ret == -ENOBUFS)
+			pr_notice_once("can-isotp: tx queue is full\n");
+	}
+	dev_put(dev);
+}
+
 static void isotp_create_fframe(struct canfd_frame *cf, struct isotp_sock *so,
 				int ae)
 {
@@ -748,19 +806,74 @@ static void isotp_create_fframe(struct canfd_frame *cf, struct isotp_sock *so,
 	so->tx.state = ISOTP_WAIT_FIRST_FC;
 }
 
+static void isotp_rcv_echo(struct sk_buff *skb, void *data)
+{
+	struct sock *sk = (struct sock *)data;
+	struct isotp_sock *so = isotp_sk(sk);
+	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
+
+	/* only handle my own local echo skb's */
+	if (skb->sk != sk || so->cfecho != *(u32 *)cf->data)
+		return;
+
+	/* cancel local echo timeout */
+	hrtimer_cancel(&so->txtimer);
+
+	/* local echo skb with consecutive frame has been consumed */
+	so->cfecho = 0;
+
+	if (so->tx.idx >= so->tx.len) {
+		/* we are done */
+		so->tx.state = ISOTP_IDLE;
+		wake_up_interruptible(&so->wait);
+		return;
+	}
+
+	if (so->txfc.bs && so->tx.bs >= so->txfc.bs) {
+		/* stop and wait for FC with timeout */
+		so->tx.state = ISOTP_WAIT_FC;
+		hrtimer_start(&so->txtimer, ktime_set(1, 0),
+			      HRTIMER_MODE_REL_SOFT);
+		return;
+	}
+
+	/* no gap between data frames needed => use burst mode */
+	if (!so->tx_gap) {
+		isotp_send_cframe(so);
+		return;
+	}
+
+	/* start timer to send next consecutive frame with correct delay */
+	hrtimer_start(&so->txtimer, so->tx_gap, HRTIMER_MODE_REL_SOFT);
+}
+
 static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
 {
 	struct isotp_sock *so = container_of(hrtimer, struct isotp_sock,
 					     txtimer);
 	struct sock *sk = &so->sk;
-	struct sk_buff *skb;
-	struct net_device *dev;
-	struct canfd_frame *cf;
 	enum hrtimer_restart restart = HRTIMER_NORESTART;
-	int can_send_ret;
-	int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0;
 
 	switch (so->tx.state) {
+	case ISOTP_SENDING:
+
+		/* cfecho should be consumed by isotp_rcv_echo() here */
+		if (!so->cfecho) {
+			/* start timeout for unlikely lost echo skb */
+			hrtimer_set_expires(&so->txtimer,
+					    ktime_add(ktime_get(),
+						      ktime_set(2, 0)));
+			restart = HRTIMER_RESTART;
+
+			/* push out the next consecutive frame */
+			isotp_send_cframe(so);
+			break;
+		}
+
+		/* cfecho has not been cleared in isotp_rcv_echo() */
+		pr_notice_once("can-isotp: cfecho %08X timeout\n", so->cfecho);
+		fallthrough;
+
 	case ISOTP_WAIT_FC:
 	case ISOTP_WAIT_FIRST_FC:
 
@@ -776,78 +889,6 @@ static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
 		wake_up_interruptible(&so->wait);
 		break;
 
-	case ISOTP_SENDING:
-
-		/* push out the next segmented pdu */
-		dev = dev_get_by_index(sock_net(sk), so->ifindex);
-		if (!dev)
-			break;
-
-isotp_tx_burst:
-		skb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv),
-				GFP_ATOMIC);
-		if (!skb) {
-			dev_put(dev);
-			break;
-		}
-
-		can_skb_reserve(skb);
-		can_skb_prv(skb)->ifindex = dev->ifindex;
-		can_skb_prv(skb)->skbcnt = 0;
-
-		cf = (struct canfd_frame *)skb->data;
-		skb_put_zero(skb, so->ll.mtu);
-
-		/* create consecutive frame */
-		isotp_fill_dataframe(cf, so, ae, 0);
-
-		/* place consecutive frame N_PCI in appropriate index */
-		cf->data[ae] = N_PCI_CF | so->tx.sn++;
-		so->tx.sn %= 16;
-		so->tx.bs++;
-
-		cf->flags = so->ll.tx_flags;
-
-		skb->dev = dev;
-		can_skb_set_owner(skb, sk);
-
-		can_send_ret = can_send(skb, 1);
-		if (can_send_ret) {
-			pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
-				       __func__, ERR_PTR(can_send_ret));
-			if (can_send_ret == -ENOBUFS)
-				pr_notice_once("can-isotp: tx queue is full, increasing txqueuelen may prevent this error\n");
-		}
-		if (so->tx.idx >= so->tx.len) {
-			/* we are done */
-			so->tx.state = ISOTP_IDLE;
-			dev_put(dev);
-			wake_up_interruptible(&so->wait);
-			break;
-		}
-
-		if (so->txfc.bs && so->tx.bs >= so->txfc.bs) {
-			/* stop and wait for FC */
-			so->tx.state = ISOTP_WAIT_FC;
-			dev_put(dev);
-			hrtimer_set_expires(&so->txtimer,
-					    ktime_add(ktime_get(),
-						      ktime_set(1, 0)));
-			restart = HRTIMER_RESTART;
-			break;
-		}
-
-		/* no gap between data frames needed => use burst mode */
-		if (!so->tx_gap)
-			goto isotp_tx_burst;
-
-		/* start timer to send next data frame with correct delay */
-		dev_put(dev);
-		hrtimer_set_expires(&so->txtimer,
-				    ktime_add(ktime_get(), so->tx_gap));
-		restart = HRTIMER_RESTART;
-		break;
-
 	default:
 		WARN_ON_ONCE(1);
 	}
@@ -1075,6 +1116,9 @@ static int isotp_release(struct socket *sock)
 				can_rx_unregister(net, dev, so->rxid,
 						  SINGLE_MASK(so->rxid),
 						  isotp_rcv, sk);
+				can_rx_unregister(net, dev, so->txid,
+						  SINGLE_MASK(so->txid),
+						  isotp_rcv_echo, sk);
 				dev_put(dev);
 				synchronize_rcu();
 			}
@@ -1161,11 +1205,20 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 
 	ifindex = dev->ifindex;
 
-	if (do_rx_reg)
+	if (do_rx_reg) {
 		can_rx_register(net, dev, addr->can_addr.tp.rx_id,
 				SINGLE_MASK(addr->can_addr.tp.rx_id),
 				isotp_rcv, sk, "isotp", sk);
 
+		/* no consecutive frame echo skb in flight */
+		so->cfecho = 0;
+
+		/* register for echo skb's */
+		can_rx_register(net, dev, addr->can_addr.tp.tx_id,
+				SINGLE_MASK(addr->can_addr.tp.tx_id),
+				isotp_rcv_echo, sk, "isotpe", sk);
+	}
+
 	dev_put(dev);
 
 	if (so->bound && do_rx_reg) {
@@ -1176,6 +1229,9 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 				can_rx_unregister(net, dev, so->rxid,
 						  SINGLE_MASK(so->rxid),
 						  isotp_rcv, sk);
+				can_rx_unregister(net, dev, so->txid,
+						  SINGLE_MASK(so->txid),
+						  isotp_rcv_echo, sk);
 				dev_put(dev);
 			}
 		}
@@ -1238,6 +1294,14 @@ static int isotp_setsockopt_locked(struct socket *sock, int level, int optname,
 		/* no separate rx_ext_address is given => use ext_address */
 		if (!(so->opt.flags & CAN_ISOTP_RX_EXT_ADDR))
 			so->opt.rx_ext_address = so->opt.ext_address;
+
+		/* check for frame_txtime changes (0 => no changes) */
+		if (so->opt.frame_txtime) {
+			if (so->opt.frame_txtime == CAN_ISOTP_FRAME_TXTIME_ZERO)
+				so->frame_txtime = 0;
+			else
+				so->frame_txtime = so->opt.frame_txtime;
+		}
 		break;
 
 	case CAN_ISOTP_RECV_FC:
@@ -1381,10 +1445,14 @@ static void isotp_notify(struct isotp_sock *so, unsigned long msg,
 	case NETDEV_UNREGISTER:
 		lock_sock(sk);
 		/* remove current filters & unregister */
-		if (so->bound && (!(so->opt.flags & CAN_ISOTP_SF_BROADCAST)))
+		if (so->bound && (!(so->opt.flags & CAN_ISOTP_SF_BROADCAST))) {
 			can_rx_unregister(dev_net(dev), dev, so->rxid,
 					  SINGLE_MASK(so->rxid),
 					  isotp_rcv, sk);
+			can_rx_unregister(dev_net(dev), dev, so->txid,
+					  SINGLE_MASK(so->txid),
+					  isotp_rcv_echo, sk);
+		}
 
 		so->ifindex = 0;
 		so->bound  = 0;
@@ -1439,6 +1507,7 @@ static int isotp_init(struct sock *sk)
 	so->opt.rxpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT;
 	so->opt.txpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT;
 	so->opt.frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME;
+	so->frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME;
 	so->rxfc.bs = CAN_ISOTP_DEFAULT_RECV_BS;
 	so->rxfc.stmin = CAN_ISOTP_DEFAULT_RECV_STMIN;
 	so->rxfc.wftmax = CAN_ISOTP_DEFAULT_RECV_WFTMAX;