Commit ffd956ee authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

can: introduce CAN midlayer private and allocate it automatically 



This patch introduces the CAN midlayer private structure ("struct
can_ml_priv") which should be used to hold protocol specific per device
data structures. For now it's only member is "struct can_dev_rcv_lists".

The CAN midlayer private is allocated via alloc_netdev()'s private and
assigned to "struct net_device::ml_priv" during device creation. This is
done transparently for CAN drivers using alloc_candev(). The slcan, vcan
and vxcan drivers which are not using alloc_candev() have been adopted
manually. The memory layout of the netdev_priv allocated via
alloc_candev() will looke like this:

  +-------------------------+
  | driver's priv           |
  +-------------------------+
  | struct can_ml_priv      |
  +-------------------------+
  | array of struct sk_buff |
  +-------------------------+

Signed-off-by: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 3f150356

drivers/net/can/dev.c

+18 −4
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/if_arp.h>

#include <linux/workqueue.h>

#include <linux/can.h>

#include <linux/can/can-ml.h>

#include <linux/can/dev.h>

#include <linux/can/skb.h>

#include <linux/can/netlink.h>
@@ -718,11 +719,24 @@ struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, 
	struct can_priv *priv;

	int size;



	/* We put the driver's priv, the CAN mid layer priv and the

	 * echo skb into the netdevice's priv. The memory layout for

	 * the netdev_priv is like this:

	 *

	 * +-------------------------+

	 * | driver's priv           |

	 * +-------------------------+

	 * | struct can_ml_priv      |

	 * +-------------------------+

	 * | array of struct sk_buff |

	 * +-------------------------+

	 */



	size = ALIGN(sizeof_priv, NETDEV_ALIGN) + sizeof(struct can_ml_priv);



	if (echo_skb_max)

		size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +

		size = ALIGN(size, sizeof(struct sk_buff *)) +

			echo_skb_max * sizeof(struct sk_buff *);

	else

		size = sizeof_priv;



	dev = alloc_netdev_mqs(size, "can%d", NET_NAME_UNKNOWN, can_setup,

			       txqs, rxqs);
@@ -735,7 +749,7 @@ struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, 
	if (echo_skb_max) {

		priv->echo_skb_max = echo_skb_max;

		priv->echo_skb = (void *)priv +

			ALIGN(sizeof_priv, sizeof(struct sk_buff *));

			(size - echo_skb_max * sizeof(struct sk_buff *));

	}



	priv->state = CAN_STATE_STOPPED;

drivers/net/can/slcan.c

+4 −1
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ 
#include <linux/workqueue.h>

#include <linux/can.h>

#include <linux/can/skb.h>

#include <linux/can/can-ml.h>



MODULE_ALIAS_LDISC(N_SLCAN);

MODULE_DESCRIPTION("serial line CAN interface");
@@ -514,6 +515,7 @@ static struct slcan *slc_alloc(void) 
	char name[IFNAMSIZ];

	struct net_device *dev = NULL;

	struct slcan       *sl;

	int size;



	for (i = 0; i < maxdev; i++) {

		dev = slcan_devs[i];
@@ -527,7 +529,8 @@ static struct slcan *slc_alloc(void) 
		return NULL;



	sprintf(name, "slcan%d", i);

	dev = alloc_netdev(sizeof(*sl), name, NET_NAME_UNKNOWN, slc_setup);

	size = ALIGN(sizeof(*sl), NETDEV_ALIGN) + sizeof(struct can_ml_priv);

	dev = alloc_netdev(size, name, NET_NAME_UNKNOWN, slc_setup);

	if (!dev)

		return NULL;

drivers/net/can/vcan.c

+4 −2
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ 
#include <linux/if_arp.h>

#include <linux/if_ether.h>

#include <linux/can.h>

#include <linux/can/can-ml.h>

#include <linux/can/dev.h>

#include <linux/can/skb.h>

#include <linux/slab.h>
@@ -163,6 +164,7 @@ static void vcan_setup(struct net_device *dev) 


static struct rtnl_link_ops vcan_link_ops __read_mostly = {

	.kind = DRV_NAME,

	.priv_size = sizeof(struct can_ml_priv),

	.setup = vcan_setup,

};

drivers/net/can/vxcan.c

+2 −1
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <linux/can/dev.h>

#include <linux/can/skb.h>

#include <linux/can/vxcan.h>

#include <linux/can/can-ml.h>

#include <linux/slab.h>

#include <net/rtnetlink.h>
@@ -281,7 +282,7 @@ static struct net *vxcan_get_link_net(const struct net_device *dev) 


static struct rtnl_link_ops vxcan_link_ops = {

	.kind		= DRV_NAME,

	.priv_size	= sizeof(struct vxcan_priv),

	.priv_size	= ALIGN(sizeof(struct vxcan_priv), NETDEV_ALIGN) + sizeof(struct can_ml_priv),

	.setup		= vxcan_setup,

	.newlink	= vxcan_newlink,

	.dellink	= vxcan_dellink,

include/linux/can/can-ml.h

0 → 100644
+66 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */

/* Copyright (c) 2002-2007 Volkswagen Group Electronic Research

 * Copyright (c) 2017 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>

 *

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of Volkswagen nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * Alternatively, provided that this notice is retained in full, this

 * software may be distributed under the terms of the GNU General

 * Public License ("GPL") version 2, in which case the provisions of the

 * GPL apply INSTEAD OF those given above.

 *

 * The provided data structures and external interfaces from this code

 * are not restricted to be used by modules with a GPL compatible license.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 */



#ifndef CAN_ML_H

#define CAN_ML_H



#include <linux/can.h>

#include <linux/list.h>



#define CAN_SFF_RCV_ARRAY_SZ (1 << CAN_SFF_ID_BITS)

#define CAN_EFF_RCV_HASH_BITS 10

#define CAN_EFF_RCV_ARRAY_SZ (1 << CAN_EFF_RCV_HASH_BITS)



enum { RX_ERR, RX_ALL, RX_FIL, RX_INV, RX_MAX };



struct can_dev_rcv_lists {

	struct hlist_head rx[RX_MAX];

	struct hlist_head rx_sff[CAN_SFF_RCV_ARRAY_SZ];

	struct hlist_head rx_eff[CAN_EFF_RCV_ARRAY_SZ];

	int remove_on_zero_entries;

	int entries;

};



struct can_ml_priv {

	struct can_dev_rcv_lists dev_rcv_lists;

};



#endif /* CAN_ML_H */

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