From e2d265d3b587f5f6f8febc0222aace93302ff0be Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:41:31 +0200 Subject: [PATCH] canfd: add support for CAN FD in CAN_RAW sockets - introduce a new sockopt CAN_RAW_FD_FRAMES to allow CAN FD frames - handle CAN frames and CAN FD frames simultaneously when enabled Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can/raw.h | 3 ++- net/can/raw.c | 50 +++++++++++++++++++++++++++++++++++++---- 2 files changed, 48 insertions(+), 5 deletions(-) diff --git a/include/linux/can/raw.h b/include/linux/can/raw.h index 781f3a3701be..a814062b0719 100644 --- a/include/linux/can/raw.h +++ b/include/linux/can/raw.h @@ -23,7 +23,8 @@ enum { CAN_RAW_FILTER = 1, /* set 0 .. n can_filter(s) */ CAN_RAW_ERR_FILTER, /* set filter for error frames */ CAN_RAW_LOOPBACK, /* local loopback (default:on) */ - CAN_RAW_RECV_OWN_MSGS /* receive my own msgs (default:off) */ + CAN_RAW_RECV_OWN_MSGS, /* receive my own msgs (default:off) */ + CAN_RAW_FD_FRAMES, /* allow CAN FD frames (default:off) */ }; #endif diff --git a/net/can/raw.c b/net/can/raw.c index 46cca3a91d19..3e9c89356a93 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -82,6 +82,7 @@ struct raw_sock { struct notifier_block notifier; int loopback; int recv_own_msgs; + int fd_frames; int count; /* number of active filters */ struct can_filter dfilter; /* default/single filter */ struct can_filter *filter; /* pointer to filter(s) */ @@ -119,6 +120,14 @@ static void raw_rcv(struct sk_buff *oskb, void *data) if (!ro->recv_own_msgs && oskb->sk == sk) return; + /* do not pass frames with DLC > 8 to a legacy socket */ + if (!ro->fd_frames) { + struct canfd_frame *cfd = (struct canfd_frame *)oskb->data; + + if (unlikely(cfd->len > CAN_MAX_DLEN)) + return; + } + /* clone the given skb to be able to enqueue it into the rcv queue */ skb = skb_clone(oskb, GFP_ATOMIC); if (!skb) @@ -291,6 +300,7 @@ static int raw_init(struct sock *sk) /* set default loopback behaviour */ ro->loopback = 1; ro->recv_own_msgs = 0; + ro->fd_frames = 0; /* set notifier */ ro->notifier.notifier_call = raw_notifier; @@ -569,6 +579,15 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, break; + case CAN_RAW_FD_FRAMES: + if (optlen != sizeof(ro->fd_frames)) + return -EINVAL; + + if (copy_from_user(&ro->fd_frames, optval, optlen)) + return -EFAULT; + + break; + default: return -ENOPROTOOPT; } @@ -627,6 +646,12 @@ static int raw_getsockopt(struct socket *sock, int level, int optname, val = &ro->recv_own_msgs; break; + case CAN_RAW_FD_FRAMES: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->fd_frames; + break; + default: return -ENOPROTOOPT; } @@ -662,8 +687,13 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock, } else ifindex = ro->ifindex; - if (size != sizeof(struct can_frame)) - return -EINVAL; + if (ro->fd_frames) { + if (unlikely(size != CANFD_MTU && size != CAN_MTU)) + return -EINVAL; + } else { + if (unlikely(size != CAN_MTU)) + return -EINVAL; + } dev = dev_get_by_index(&init_net, ifindex); if (!dev) @@ -705,7 +735,9 @@ static int raw_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct sock *sk = sock->sk; + struct raw_sock *ro = raw_sk(sk); struct sk_buff *skb; + int rxmtu; int err = 0; int noblock; @@ -716,10 +748,20 @@ static int raw_recvmsg(struct kiocb *iocb, struct socket *sock, if (!skb) return err; - if (size < skb->len) + /* + * when serving a legacy socket the DLC <= 8 is already checked inside + * raw_rcv(). Now check if we need to pass a canfd_frame to a legacy + * socket and cut the possible CANFD_MTU/CAN_MTU length to CAN_MTU + */ + if (!ro->fd_frames) + rxmtu = CAN_MTU; + else + rxmtu = skb->len; + + if (size < rxmtu) msg->msg_flags |= MSG_TRUNC; else - size = skb->len; + size = rxmtu; err = memcpy_toiovec(msg->msg_iov, skb->data, size); if (err < 0) { -- 2.30.2