can: dev: move skb related into seperate file

This patch moves the skb related code of the CAN device infrastructure into a
separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Marc Kleine-Budde 2021-01-11 15:19:20 +01:00
parent bdd2e41319
commit 18f2dbfd22
5 changed files with 298 additions and 289 deletions

View File

@ -5,5 +5,6 @@ can-dev-y += bittiming.o
can-dev-y += dev.o can-dev-y += dev.o
can-dev-y += length.o can-dev-y += length.o
can-dev-y += rx-offload.o can-dev-y += rx-offload.o
can-dev-y += skb.o
can-dev-$(CONFIG_CAN_LEDS) += led.o can-dev-$(CONFIG_CAN_LEDS) += led.o

View File

@ -132,149 +132,6 @@ void can_change_state(struct net_device *dev, struct can_frame *cf,
} }
EXPORT_SYMBOL_GPL(can_change_state); EXPORT_SYMBOL_GPL(can_change_state);
/* Local echo of CAN messages
*
* CAN network devices *should* support a local echo functionality
* (see Documentation/networking/can.rst). To test the handling of CAN
* interfaces that do not support the local echo both driver types are
* implemented. In the case that the driver does not support the echo
* the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
* to perform the echo as a fallback solution.
*/
static void can_flush_echo_skb(struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
int i;
for (i = 0; i < priv->echo_skb_max; i++) {
if (priv->echo_skb[i]) {
kfree_skb(priv->echo_skb[i]);
priv->echo_skb[i] = NULL;
stats->tx_dropped++;
stats->tx_aborted_errors++;
}
}
}
/* Put the skb on the stack to be looped backed locally lateron
*
* The function is typically called in the start_xmit function
* of the device driver. The driver must protect access to
* priv->echo_skb, if necessary.
*/
int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
unsigned int idx)
{
struct can_priv *priv = netdev_priv(dev);
BUG_ON(idx >= priv->echo_skb_max);
/* check flag whether this packet has to be looped back */
if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
(skb->protocol != htons(ETH_P_CAN) &&
skb->protocol != htons(ETH_P_CANFD))) {
kfree_skb(skb);
return 0;
}
if (!priv->echo_skb[idx]) {
skb = can_create_echo_skb(skb);
if (!skb)
return -ENOMEM;
/* make settings for echo to reduce code in irq context */
skb->pkt_type = PACKET_BROADCAST;
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->dev = dev;
/* save this skb for tx interrupt echo handling */
priv->echo_skb[idx] = skb;
} else {
/* locking problem with netif_stop_queue() ?? */
netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx);
kfree_skb(skb);
return -EBUSY;
}
return 0;
}
EXPORT_SYMBOL_GPL(can_put_echo_skb);
struct sk_buff *
__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr)
{
struct can_priv *priv = netdev_priv(dev);
if (idx >= priv->echo_skb_max) {
netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
__func__, idx, priv->echo_skb_max);
return NULL;
}
if (priv->echo_skb[idx]) {
/* Using "struct canfd_frame::len" for the frame
* length is supported on both CAN and CANFD frames.
*/
struct sk_buff *skb = priv->echo_skb[idx];
struct canfd_frame *cf = (struct canfd_frame *)skb->data;
/* get the real payload length for netdev statistics */
if (cf->can_id & CAN_RTR_FLAG)
*len_ptr = 0;
else
*len_ptr = cf->len;
priv->echo_skb[idx] = NULL;
return skb;
}
return NULL;
}
/* Get the skb from the stack and loop it back locally
*
* The function is typically called when the TX done interrupt
* is handled in the device driver. The driver must protect
* access to priv->echo_skb, if necessary.
*/
unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
{
struct sk_buff *skb;
u8 len;
skb = __can_get_echo_skb(dev, idx, &len);
if (!skb)
return 0;
skb_get(skb);
if (netif_rx(skb) == NET_RX_SUCCESS)
dev_consume_skb_any(skb);
else
dev_kfree_skb_any(skb);
return len;
}
EXPORT_SYMBOL_GPL(can_get_echo_skb);
/* Remove the skb from the stack and free it.
*
* The function is typically called when TX failed.
*/
void can_free_echo_skb(struct net_device *dev, unsigned int idx)
{
struct can_priv *priv = netdev_priv(dev);
BUG_ON(idx >= priv->echo_skb_max);
if (priv->echo_skb[idx]) {
dev_kfree_skb_any(priv->echo_skb[idx]);
priv->echo_skb[idx] = NULL;
}
}
EXPORT_SYMBOL_GPL(can_free_echo_skb);
/* CAN device restart for bus-off recovery */ /* CAN device restart for bus-off recovery */
static void can_restart(struct net_device *dev) static void can_restart(struct net_device *dev)
{ {
@ -379,76 +236,6 @@ static void can_setup(struct net_device *dev)
dev->features = NETIF_F_HW_CSUM; dev->features = NETIF_F_HW_CSUM;
} }
struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
{
struct sk_buff *skb;
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
sizeof(struct can_frame));
if (unlikely(!skb))
return NULL;
skb->protocol = htons(ETH_P_CAN);
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);
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
*cf = skb_put_zero(skb, sizeof(struct can_frame));
return skb;
}
EXPORT_SYMBOL_GPL(alloc_can_skb);
struct sk_buff *alloc_canfd_skb(struct net_device *dev,
struct canfd_frame **cfd)
{
struct sk_buff *skb;
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
sizeof(struct canfd_frame));
if (unlikely(!skb))
return NULL;
skb->protocol = htons(ETH_P_CANFD);
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);
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
*cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
return skb;
}
EXPORT_SYMBOL_GPL(alloc_canfd_skb);
struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
{
struct sk_buff *skb;
skb = alloc_can_skb(dev, cf);
if (unlikely(!skb))
return NULL;
(*cf)->can_id = CAN_ERR_FLAG;
(*cf)->len = CAN_ERR_DLC;
return skb;
}
EXPORT_SYMBOL_GPL(alloc_can_err_skb);
/* Allocate and setup space for the CAN network device */ /* Allocate and setup space for the CAN network device */
struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
unsigned int txqs, unsigned int rxqs) unsigned int txqs, unsigned int rxqs)

220
drivers/net/can/dev/skb.c Normal file
View File

@ -0,0 +1,220 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
* Copyright (C) 2006 Andrey Volkov, Varma Electronics
* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
*/
#include <linux/can/dev.h>
/* Local echo of CAN messages
*
* CAN network devices *should* support a local echo functionality
* (see Documentation/networking/can.rst). To test the handling of CAN
* interfaces that do not support the local echo both driver types are
* implemented. In the case that the driver does not support the echo
* the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
* to perform the echo as a fallback solution.
*/
void can_flush_echo_skb(struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
int i;
for (i = 0; i < priv->echo_skb_max; i++) {
if (priv->echo_skb[i]) {
kfree_skb(priv->echo_skb[i]);
priv->echo_skb[i] = NULL;
stats->tx_dropped++;
stats->tx_aborted_errors++;
}
}
}
/* Put the skb on the stack to be looped backed locally lateron
*
* The function is typically called in the start_xmit function
* of the device driver. The driver must protect access to
* priv->echo_skb, if necessary.
*/
int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
unsigned int idx)
{
struct can_priv *priv = netdev_priv(dev);
BUG_ON(idx >= priv->echo_skb_max);
/* check flag whether this packet has to be looped back */
if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
(skb->protocol != htons(ETH_P_CAN) &&
skb->protocol != htons(ETH_P_CANFD))) {
kfree_skb(skb);
return 0;
}
if (!priv->echo_skb[idx]) {
skb = can_create_echo_skb(skb);
if (!skb)
return -ENOMEM;
/* make settings for echo to reduce code in irq context */
skb->pkt_type = PACKET_BROADCAST;
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->dev = dev;
/* save this skb for tx interrupt echo handling */
priv->echo_skb[idx] = skb;
} else {
/* locking problem with netif_stop_queue() ?? */
netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx);
kfree_skb(skb);
return -EBUSY;
}
return 0;
}
EXPORT_SYMBOL_GPL(can_put_echo_skb);
struct sk_buff *
__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr)
{
struct can_priv *priv = netdev_priv(dev);
if (idx >= priv->echo_skb_max) {
netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
__func__, idx, priv->echo_skb_max);
return NULL;
}
if (priv->echo_skb[idx]) {
/* Using "struct canfd_frame::len" for the frame
* length is supported on both CAN and CANFD frames.
*/
struct sk_buff *skb = priv->echo_skb[idx];
struct canfd_frame *cf = (struct canfd_frame *)skb->data;
/* get the real payload length for netdev statistics */
if (cf->can_id & CAN_RTR_FLAG)
*len_ptr = 0;
else
*len_ptr = cf->len;
priv->echo_skb[idx] = NULL;
return skb;
}
return NULL;
}
/* Get the skb from the stack and loop it back locally
*
* The function is typically called when the TX done interrupt
* is handled in the device driver. The driver must protect
* access to priv->echo_skb, if necessary.
*/
unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
{
struct sk_buff *skb;
u8 len;
skb = __can_get_echo_skb(dev, idx, &len);
if (!skb)
return 0;
skb_get(skb);
if (netif_rx(skb) == NET_RX_SUCCESS)
dev_consume_skb_any(skb);
else
dev_kfree_skb_any(skb);
return len;
}
EXPORT_SYMBOL_GPL(can_get_echo_skb);
/* Remove the skb from the stack and free it.
*
* The function is typically called when TX failed.
*/
void can_free_echo_skb(struct net_device *dev, unsigned int idx)
{
struct can_priv *priv = netdev_priv(dev);
BUG_ON(idx >= priv->echo_skb_max);
if (priv->echo_skb[idx]) {
dev_kfree_skb_any(priv->echo_skb[idx]);
priv->echo_skb[idx] = NULL;
}
}
EXPORT_SYMBOL_GPL(can_free_echo_skb);
struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
{
struct sk_buff *skb;
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
sizeof(struct can_frame));
if (unlikely(!skb))
return NULL;
skb->protocol = htons(ETH_P_CAN);
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);
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
*cf = skb_put_zero(skb, sizeof(struct can_frame));
return skb;
}
EXPORT_SYMBOL_GPL(alloc_can_skb);
struct sk_buff *alloc_canfd_skb(struct net_device *dev,
struct canfd_frame **cfd)
{
struct sk_buff *skb;
skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
sizeof(struct canfd_frame));
if (unlikely(!skb))
return NULL;
skb->protocol = htons(ETH_P_CANFD);
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);
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
*cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
return skb;
}
EXPORT_SYMBOL_GPL(alloc_canfd_skb);
struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
{
struct sk_buff *skb;
skb = alloc_can_skb(dev, cf);
if (unlikely(!skb))
return NULL;
(*cf)->can_id = CAN_ERR_FLAG;
(*cf)->len = CAN_ERR_DLC;
return skb;
}
EXPORT_SYMBOL_GPL(alloc_can_err_skb);

View File

@ -84,69 +84,6 @@ struct can_priv {
#endif #endif
}; };
/* Check for outgoing skbs that have not been created by the CAN subsystem */
static inline bool can_skb_headroom_valid(struct net_device *dev,
struct sk_buff *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) {
/* init headroom */
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
skb->ip_summed = CHECKSUM_UNNECESSARY;
/* perform proper loopback on capable devices */
if (dev->flags & IFF_ECHO)
skb->pkt_type = PACKET_LOOPBACK;
else
skb->pkt_type = PACKET_HOST;
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
}
return true;
}
/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
static inline bool can_dropped_invalid_skb(struct net_device *dev,
struct sk_buff *skb)
{
const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
if (skb->protocol == htons(ETH_P_CAN)) {
if (unlikely(skb->len != CAN_MTU ||
cfd->len > CAN_MAX_DLEN))
goto inval_skb;
} else if (skb->protocol == htons(ETH_P_CANFD)) {
if (unlikely(skb->len != CANFD_MTU ||
cfd->len > CANFD_MAX_DLEN))
goto inval_skb;
} else
goto inval_skb;
if (!can_skb_headroom_valid(dev, skb))
goto inval_skb;
return false;
inval_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return true;
}
static inline bool can_is_canfd_skb(const struct sk_buff *skb)
{
/* the CAN specific type of skb is identified by its data length */
return skb->len == CANFD_MTU;
}
/* helper to define static CAN controller features at device creation time */ /* helper to define static CAN controller features at device creation time */
static inline void can_set_static_ctrlmode(struct net_device *dev, static inline void can_set_static_ctrlmode(struct net_device *dev,
@ -187,23 +124,10 @@ void can_bus_off(struct net_device *dev);
void can_change_state(struct net_device *dev, struct can_frame *cf, void can_change_state(struct net_device *dev, struct can_frame *cf,
enum can_state tx_state, enum can_state rx_state); enum can_state tx_state, enum can_state rx_state);
int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
unsigned int idx);
struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
u8 *len_ptr);
unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
void can_free_echo_skb(struct net_device *dev, unsigned int idx);
#ifdef CONFIG_OF #ifdef CONFIG_OF
void of_can_transceiver(struct net_device *dev); void of_can_transceiver(struct net_device *dev);
#else #else
static inline void of_can_transceiver(struct net_device *dev) { } static inline void of_can_transceiver(struct net_device *dev) { }
#endif #endif
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_can_err_skb(struct net_device *dev,
struct can_frame **cf);
#endif /* !_CAN_DEV_H */ #endif /* !_CAN_DEV_H */

View File

@ -16,6 +16,19 @@
#include <linux/can.h> #include <linux/can.h>
#include <net/sock.h> #include <net/sock.h>
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);
struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
u8 *len_ptr);
unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
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_can_err_skb(struct net_device *dev,
struct can_frame **cf);
/* /*
* The struct can_skb_priv is used to transport additional information along * 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 * with the stored struct can(fd)_frame that can not be contained in existing
@ -74,4 +87,68 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb)
return nskb; return nskb;
} }
/* Check for outgoing skbs that have not been created by the CAN subsystem */
static inline bool can_skb_headroom_valid(struct net_device *dev,
struct sk_buff *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) {
/* init headroom */
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
skb->ip_summed = CHECKSUM_UNNECESSARY;
/* perform proper loopback on capable devices */
if (dev->flags & IFF_ECHO)
skb->pkt_type = PACKET_LOOPBACK;
else
skb->pkt_type = PACKET_HOST;
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
}
return true;
}
/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
static inline bool can_dropped_invalid_skb(struct net_device *dev,
struct sk_buff *skb)
{
const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
if (skb->protocol == htons(ETH_P_CAN)) {
if (unlikely(skb->len != CAN_MTU ||
cfd->len > CAN_MAX_DLEN))
goto inval_skb;
} else if (skb->protocol == htons(ETH_P_CANFD)) {
if (unlikely(skb->len != CANFD_MTU ||
cfd->len > CANFD_MAX_DLEN))
goto inval_skb;
} else
goto inval_skb;
if (!can_skb_headroom_valid(dev, skb))
goto inval_skb;
return false;
inval_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return true;
}
static inline bool can_is_canfd_skb(const struct sk_buff *skb)
{
/* the CAN specific type of skb is identified by its data length */
return skb->len == CANFD_MTU;
}
#endif /* !_CAN_SKB_H */ #endif /* !_CAN_SKB_H */