Commit 9f10374b authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Paolo Abeni
Browse files

can: remove private CAN skb headroom infrastructure 



This patch removes struct can_skb_priv which was stored at skb->head and
the can_skb_reserve() helper which was used to shift skb->head.

Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-5-3635d790fe8b@hartkopp.net


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent d2d91797

drivers/net/can/dev/skb.c

+9 −22
Original line number Diff line number Diff line
@@ -206,16 +206,10 @@ void can_free_echo_skb(struct net_device *dev, unsigned int idx, 
EXPORT_SYMBOL_GPL(can_free_echo_skb);



/* fill common values for CAN sk_buffs */

static void init_can_skb_reserve(struct sk_buff *skb)

static void init_can_skb(struct sk_buff *skb)

{

	skb->pkt_type = PACKET_BROADCAST;

	skb->ip_summed = CHECKSUM_UNNECESSARY;



	skb_reset_mac_header(skb);

	skb_reset_network_header(skb);

	skb_reset_transport_header(skb);



	can_skb_reserve(skb);

}



struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
@@ -223,8 +217,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) 
	struct sk_buff *skb;

	struct can_skb_ext *csx;



	skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +

			       sizeof(struct can_frame));

	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));

	if (unlikely(!skb))

		goto out_error_cc;
@@ -235,7 +228,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) 
	}



	skb->protocol = htons(ETH_P_CAN);

	init_can_skb_reserve(skb);

	init_can_skb(skb);

	csx->can_iif = dev->ifindex;



	*cf = skb_put_zero(skb, sizeof(struct can_frame));
@@ -255,8 +248,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev, 
	struct sk_buff *skb;

	struct can_skb_ext *csx;



	skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +

			       sizeof(struct canfd_frame));

	skb = netdev_alloc_skb(dev, sizeof(struct canfd_frame));

	if (unlikely(!skb))

		goto out_error_fd;
@@ -267,7 +259,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev, 
	}



	skb->protocol = htons(ETH_P_CANFD);

	init_can_skb_reserve(skb);

	init_can_skb(skb);

	csx->can_iif = dev->ifindex;



	*cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
@@ -294,8 +286,7 @@ struct sk_buff *alloc_canxl_skb(struct net_device *dev, 
	if (data_len < CANXL_MIN_DLEN || data_len > CANXL_MAX_DLEN)

		goto out_error_xl;



	skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +

			       CANXL_HDR_SIZE + data_len);

	skb = netdev_alloc_skb(dev, CANXL_HDR_SIZE + data_len);

	if (unlikely(!skb))

		goto out_error_xl;
@@ -306,7 +297,7 @@ struct sk_buff *alloc_canxl_skb(struct net_device *dev, 
	}



	skb->protocol = htons(ETH_P_CANXL);

	init_can_skb_reserve(skb);

	init_can_skb(skb);

	csx->can_iif = dev->ifindex;



	*cxl = skb_put_zero(skb, CANXL_HDR_SIZE + data_len);
@@ -340,14 +331,10 @@ struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf) 
EXPORT_SYMBOL_GPL(alloc_can_err_skb);



/* Check for outgoing skbs that have not been created by the CAN subsystem */

static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb)

static bool can_skb_init_valid(struct net_device *dev, struct sk_buff *skb)

{

	struct can_skb_ext *csx = can_skb_ext_find(skb);



	/* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */

	if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))

		return false;



	/* af_packet does not apply CAN skb specific settings */

	if (skb->ip_summed == CHECKSUM_NONE || !csx) {

		/* init CAN skb content */
@@ -405,7 +392,7 @@ bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) 
		goto inval_skb;

	}



	if (!can_skb_headroom_valid(dev, skb))

	if (!can_skb_init_valid(dev, skb))

		goto inval_skb;



	return false;

include/linux/can/skb.h

+0 −31
Original line number Diff line number Diff line
@@ -38,37 +38,6 @@ 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);



/*

 * The struct can_skb_priv is used to transport additional information along

 * with the stored struct can(fd)_frame that can not be contained in existing

 * struct sk_buff elements.

 * N.B. that this information must not be modified in cloned CAN sk_buffs.

 * To modify the CAN frame content or the struct can_skb_priv content

 * skb_copy() needs to be used instead of skb_clone().

 */



/**

 * struct can_skb_priv - private additional data inside CAN sk_buffs

 * @ifindex:	ifindex of the first interface the CAN frame appeared on

 * @frame_len:	length of CAN frame in data link layer

 * @cf:		align to the following CAN frame at skb->data

 */

struct can_skb_priv {

	int ifindex;

	unsigned int frame_len;

	struct can_frame cf[];

};



static inline struct can_skb_priv *can_skb_prv(struct sk_buff *skb)

{

	return (struct can_skb_priv *)(skb->head);

}



static inline void can_skb_reserve(struct sk_buff *skb)

{

	skb_reserve(skb, sizeof(struct can_skb_priv));

}



static inline struct can_skb_ext *can_skb_ext_add(struct sk_buff *skb)

{

	struct can_skb_ext *csx = skb_ext_add(skb, SKB_EXT_CAN);

net/can/bcm.c

+2 −5
Original line number Diff line number Diff line
@@ -312,7 +312,7 @@ static void bcm_can_tx(struct bcm_op *op) 
		return;

	}



	skb = alloc_skb(op->cfsiz + sizeof(struct can_skb_priv), gfp_any());

	skb = alloc_skb(op->cfsiz, gfp_any());

	if (!skb)

		goto out;
@@ -322,7 +322,6 @@ static void bcm_can_tx(struct bcm_op *op) 
		goto out;

	}



	can_skb_reserve(skb);

	csx->can_iif = dev->ifindex;



	skb_put_data(skb, cf, op->cfsiz);
@@ -1333,7 +1332,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk, 
	if (!ifindex)

		return -ENODEV;



	skb = alloc_skb(cfsiz + sizeof(struct can_skb_priv), GFP_KERNEL);

	skb = alloc_skb(cfsiz, GFP_KERNEL);

	if (!skb)

		return -ENOMEM;
@@ -1343,8 +1342,6 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk, 
		return -ENOMEM;

	}



	can_skb_reserve(skb);



	err = memcpy_from_msg(skb_put(skb, cfsiz), msg, cfsiz);

	if (err < 0) {

		kfree_skb(skb);

net/can/isotp.c

+4 −8
Original line number Diff line number Diff line
@@ -220,7 +220,7 @@ static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus) 
	struct isotp_sock *so = isotp_sk(sk);

	int can_send_ret;



	nskb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), gfp_any());

	nskb = alloc_skb(so->ll.mtu, gfp_any());

	if (!nskb)

		return 1;
@@ -236,9 +236,7 @@ static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus) 
		return 1;

	}



	can_skb_reserve(nskb);

	csx->can_iif = dev->ifindex;



	nskb->dev = dev;

	can_skb_set_owner(nskb, sk);

	ncf = (struct canfd_frame *)nskb->data;
@@ -780,7 +778,7 @@ static void isotp_send_cframe(struct isotp_sock *so) 
	if (!dev)

		return;



	skb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), GFP_ATOMIC);

	skb = alloc_skb(so->ll.mtu, GFP_ATOMIC);

	if (!skb) {

		dev_put(dev);

		return;
@@ -793,7 +791,6 @@ static void isotp_send_cframe(struct isotp_sock *so) 
		return;

	}



	can_skb_reserve(skb);

	csx->can_iif = dev->ifindex;



	cf = (struct canfd_frame *)skb->data;
@@ -1015,8 +1012,8 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 
		goto err_out_drop;

	}



	skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv),

				  msg->msg_flags & MSG_DONTWAIT, &err);

	skb = sock_alloc_send_skb(sk, so->ll.mtu, msg->msg_flags & MSG_DONTWAIT,

				  &err);

	if (!skb) {

		dev_put(dev);

		goto err_out_drop;
@@ -1030,7 +1027,6 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 
		goto err_out_drop;

	}



	can_skb_reserve(skb);

	csx->can_iif = dev->ifindex;



	so->tx.len = size;

net/can/j1939/socket.c

+1 −3
Original line number Diff line number Diff line
@@ -891,8 +891,7 @@ static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev, 
	skb = sock_alloc_send_skb(sk,

				  size +

				  sizeof(struct can_frame) -

				  sizeof(((struct can_frame *)NULL)->data) +

				  sizeof(struct can_skb_priv),

				  sizeof(((struct can_frame *)NULL)->data),

				  msg->msg_flags & MSG_DONTWAIT, &ret);

	if (!skb)

		goto failure;
@@ -904,7 +903,6 @@ static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev, 
		goto failure;

	}



	can_skb_reserve(skb);

	csx->can_iif = ndev->ifindex;

	skb_reserve(skb, offsetof(struct can_frame, data));