canfd: add support for CAN FD in PF_CAN core
- handle ETH_P_CAN and ETH_P_CANFD skbuffs
- update sanity checks for CAN and CAN FD
- make sure the CAN frame can pass the selected CAN netdevice on send
- bump core version and abi version to indicate the new CAN FD support
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/include/linux/can/core.h b/include/linux/can/core.h
index 0ccc1cd..78c6c52 100644
--- a/include/linux/can/core.h
+++ b/include/linux/can/core.h
@@ -17,10 +17,10 @@
#include <linux/skbuff.h>
#include <linux/netdevice.h>
-#define CAN_VERSION "20090105"
+#define CAN_VERSION "20120528"
/* increment this number each time you change some user-space interface */
-#define CAN_ABI_VERSION "8"
+#define CAN_ABI_VERSION "9"
#define CAN_VERSION_STRING "rev " CAN_VERSION " abi " CAN_ABI_VERSION
diff --git a/net/can/af_can.c b/net/can/af_can.c
index c96140a..821022a 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -221,30 +221,46 @@
* -ENOBUFS on full driver queue (see net_xmit_errno())
* -ENOMEM when local loopback failed at calling skb_clone()
* -EPERM when trying to send on a non-CAN interface
+ * -EMSGSIZE CAN frame size is bigger than CAN interface MTU
* -EINVAL when the skb->data does not contain a valid CAN frame
*/
int can_send(struct sk_buff *skb, int loop)
{
struct sk_buff *newskb = NULL;
- struct can_frame *cf = (struct can_frame *)skb->data;
- int err;
+ struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+ int err = -EINVAL;
- if (skb->len != sizeof(struct can_frame) || cf->can_dlc > 8) {
- kfree_skb(skb);
- return -EINVAL;
+ if (skb->len == CAN_MTU) {
+ skb->protocol = htons(ETH_P_CAN);
+ if (unlikely(cfd->len > CAN_MAX_DLEN))
+ goto inval_skb;
+ } else if (skb->len == CANFD_MTU) {
+ skb->protocol = htons(ETH_P_CANFD);
+ if (unlikely(cfd->len > CANFD_MAX_DLEN))
+ goto inval_skb;
+ } else
+ goto inval_skb;
+
+ /*
+ * Make sure the CAN frame can pass the selected CAN netdevice.
+ * As structs can_frame and canfd_frame are similar, we can provide
+ * CAN FD frames to legacy CAN drivers as long as the length is <= 8
+ */
+ if (unlikely(skb->len > skb->dev->mtu && cfd->len > CAN_MAX_DLEN)) {
+ err = -EMSGSIZE;
+ goto inval_skb;
}
- if (skb->dev->type != ARPHRD_CAN) {
- kfree_skb(skb);
- return -EPERM;
+ if (unlikely(skb->dev->type != ARPHRD_CAN)) {
+ err = -EPERM;
+ goto inval_skb;
}
- if (!(skb->dev->flags & IFF_UP)) {
- kfree_skb(skb);
- return -ENETDOWN;
+ if (unlikely(!(skb->dev->flags & IFF_UP))) {
+ err = -ENETDOWN;
+ goto inval_skb;
}
- skb->protocol = htons(ETH_P_CAN);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
@@ -301,6 +317,10 @@
can_stats.tx_frames_delta++;
return 0;
+
+inval_skb:
+ kfree_skb(skb);
+ return err;
}
EXPORT_SYMBOL(can_send);
@@ -633,24 +653,11 @@
return matches;
}
-static int can_rcv(struct sk_buff *skb, struct net_device *dev,
- struct packet_type *pt, struct net_device *orig_dev)
+static void can_receive(struct sk_buff *skb, struct net_device *dev)
{
struct dev_rcv_lists *d;
- struct can_frame *cf = (struct can_frame *)skb->data;
int matches;
- if (!net_eq(dev_net(dev), &init_net))
- goto drop;
-
- if (WARN_ONCE(dev->type != ARPHRD_CAN ||
- skb->len != sizeof(struct can_frame) ||
- cf->can_dlc > 8,
- "PF_CAN: dropped non conform skbuf: "
- "dev type %d, len %d, can_dlc %d\n",
- dev->type, skb->len, cf->can_dlc))
- goto drop;
-
/* update statistics */
can_stats.rx_frames++;
can_stats.rx_frames_delta++;
@@ -674,7 +681,49 @@
can_stats.matches++;
can_stats.matches_delta++;
}
+}
+static int can_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+ if (unlikely(!net_eq(dev_net(dev), &init_net)))
+ goto drop;
+
+ if (WARN_ONCE(dev->type != ARPHRD_CAN ||
+ skb->len != CAN_MTU ||
+ cfd->len > CAN_MAX_DLEN,
+ "PF_CAN: dropped non conform CAN skbuf: "
+ "dev type %d, len %d, datalen %d\n",
+ dev->type, skb->len, cfd->len))
+ goto drop;
+
+ can_receive(skb, dev);
+ return NET_RX_SUCCESS;
+
+drop:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+static int canfd_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+ if (unlikely(!net_eq(dev_net(dev), &init_net)))
+ goto drop;
+
+ if (WARN_ONCE(dev->type != ARPHRD_CAN ||
+ skb->len != CANFD_MTU ||
+ cfd->len > CANFD_MAX_DLEN,
+ "PF_CAN: dropped non conform CAN FD skbuf: "
+ "dev type %d, len %d, datalen %d\n",
+ dev->type, skb->len, cfd->len))
+ goto drop;
+
+ can_receive(skb, dev);
return NET_RX_SUCCESS;
drop:
@@ -808,10 +857,14 @@
static struct packet_type can_packet __read_mostly = {
.type = cpu_to_be16(ETH_P_CAN),
- .dev = NULL,
.func = can_rcv,
};
+static struct packet_type canfd_packet __read_mostly = {
+ .type = cpu_to_be16(ETH_P_CANFD),
+ .func = canfd_rcv,
+};
+
static const struct net_proto_family can_family_ops = {
.family = PF_CAN,
.create = can_create,
@@ -853,6 +906,7 @@
sock_register(&can_family_ops);
register_netdevice_notifier(&can_netdev_notifier);
dev_add_pack(&can_packet);
+ dev_add_pack(&canfd_packet);
return 0;
}
@@ -867,6 +921,7 @@
can_remove_proc();
/* protocol unregister */
+ dev_remove_pack(&canfd_packet);
dev_remove_pack(&can_packet);
unregister_netdevice_notifier(&can_netdev_notifier);
sock_unregister(PF_CAN);