2 files changed, 60 insertions, 2 deletions

diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index c3e50e537e39..58f5431a5559 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -147,6 +147,11 @@ static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
 	return priv->ctrlmode & ~priv->ctrlmode_supported;
 }
 
+static inline bool can_is_canxl_dev_mtu(unsigned int mtu)
+{
+	return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU);
+}
+
 void can_setup(struct net_device *dev);
 
 struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h
index 182749e858b3..1abc25a8d144 100644
--- a/include/linux/can/skb.h
+++ b/include/linux/can/skb.h
@@ -20,7 +20,8 @@ void can_flush_echo_skb(struct net_device *dev);
 int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 		     unsigned int idx, unsigned int frame_len);
 struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
-				   u8 *len_ptr, unsigned int *frame_len_ptr);
+				   unsigned int *len_ptr,
+				   unsigned int *frame_len_ptr);
 unsigned int __must_check can_get_echo_skb(struct net_device *dev,
 					   unsigned int idx,
 					   unsigned int *frame_len_ptr);
@@ -29,6 +30,9 @@ void can_free_echo_skb(struct net_device *dev, unsigned int idx,
 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 				struct canfd_frame **cfd);
+struct sk_buff *alloc_canxl_skb(struct net_device *dev,
+				struct canxl_frame **cxl,
+				unsigned int data_len);
 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
 				  struct can_frame **cf);
 bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb);
@@ -97,10 +101,59 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb)
 	return nskb;
 }
 
+static inline bool can_is_can_skb(const struct sk_buff *skb)
+{
+	struct can_frame *cf = (struct can_frame *)skb->data;
+
+	/* the CAN specific type of skb is identified by its data length */
+	return (skb->len == CAN_MTU && cf->len <= CAN_MAX_DLEN);
+}
+
 static inline bool can_is_canfd_skb(const struct sk_buff *skb)
 {
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
 	/* the CAN specific type of skb is identified by its data length */
-	return skb->len == CANFD_MTU;
+	return (skb->len == CANFD_MTU && cfd->len <= CANFD_MAX_DLEN);
+}
+
+static inline bool can_is_canxl_skb(const struct sk_buff *skb)
+{
+	const struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
+
+	if (skb->len < CANXL_HDR_SIZE + CANXL_MIN_DLEN || skb->len > CANXL_MTU)
+		return false;
+
+	/* this also checks valid CAN XL data length boundaries */
+	if (skb->len != CANXL_HDR_SIZE + cxl->len)
+		return false;
+
+	return cxl->flags & CANXL_XLF;
+}
+
+/* get length element value from can[|fd|xl]_frame structure */
+static inline unsigned int can_skb_get_len_val(struct sk_buff *skb)
+{
+	const struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
+	const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+	if (can_is_canxl_skb(skb))
+		return cxl->len;
+
+	return cfd->len;
+}
+
+/* get needed data length inside CAN frame for all frame types (RTR aware) */
+static inline unsigned int can_skb_get_data_len(struct sk_buff *skb)
+{
+	unsigned int len = can_skb_get_len_val(skb);
+	const struct can_frame *cf = (struct can_frame *)skb->data;
+
+	/* RTR frames have an actual length of zero */
+	if (can_is_can_skb(skb) && cf->can_id & CAN_RTR_FLAG)
+		return 0;
+
+	return len;
 }
 
 #endif /* !_CAN_SKB_H */