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The can_skb_priv::skbcnt variable is used to identify CAN skbs in the RX path analogue to the skb->hash. As the skb hash is not filled in CAN skbs move the private skbcnt value to skb->hash and set skb->sw_hash accordingly. The skb->hash is a value used for RPS to identify skbs. Use it as intended. Signed-off-by: Marc Kleine-Budde Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260201-can_skb_ext-v8-1-3635d790fe8b@hartkopp.net Signed-off-by: Paolo Abeni Signed-off-by: Oliver Hartkopp --- drivers/net/can/dev/skb.c | 2 -- include/linux/can/core.h | 1 + include/linux/can/skb.h | 2 -- net/can/af_can.c | 14 +++++++++++--- net/can/bcm.c | 2 -- net/can/isotp.c | 3 --- net/can/j1939/socket.c | 1 - net/can/j1939/transport.c | 2 -- net/can/raw.c | 7 +++---- 9 files changed, 15 insertions(+), 19 deletions(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index 3ebd4f779b9b..0da615afa04d 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -200,11 +200,10 @@ static void init_can_skb_reserve(struct sk_buff *skb) skb_reset_mac_header(skb); skb_reset_network_header(skb); skb_reset_transport_header(skb); can_skb_reserve(skb); - can_skb_prv(skb)->skbcnt = 0; } struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) { struct sk_buff *skb; @@ -310,11 +309,10 @@ static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb) /* 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) diff --git a/include/linux/can/core.h b/include/linux/can/core.h index 5fb8d0e3f9c1..3287232e3cad 100644 --- a/include/linux/can/core.h +++ b/include/linux/can/core.h @@ -56,8 +56,9 @@ extern void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id, canid_t mask, void (*func)(struct sk_buff *, void *), void *data); extern int can_send(struct sk_buff *skb, int loop); +void can_set_skb_uid(struct sk_buff *skb); void can_sock_destruct(struct sock *sk); #endif /* !_CAN_CORE_H */ diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h index 1abc25a8d144..869ea574a40a 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -47,17 +47,15 @@ bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb); */ /** * struct can_skb_priv - private additional data inside CAN sk_buffs * @ifindex: ifindex of the first interface the CAN frame appeared on - * @skbcnt: atomic counter to have an unique id together with skb pointer * @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; - int skbcnt; unsigned int frame_len; struct can_frame cf[]; }; static inline struct can_skb_priv *can_skb_prv(struct sk_buff *skb) diff --git a/net/can/af_can.c b/net/can/af_can.c index a624c04ed5c6..7a026f3a70a0 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -639,10 +639,20 @@ static int can_rcv_filter(struct can_dev_rcv_lists *dev_rcv_lists, struct sk_buf } return matches; } +void can_set_skb_uid(struct sk_buff *skb) +{ + /* create non-zero unique skb identifier together with *skb */ + while (!(skb->hash)) + skb->hash = atomic_inc_return(&skbcounter); + + skb->sw_hash = 1; +} +EXPORT_SYMBOL(can_set_skb_uid); + static void can_receive(struct sk_buff *skb, struct net_device *dev) { struct can_dev_rcv_lists *dev_rcv_lists; struct net *net = dev_net(dev); struct can_pkg_stats *pkg_stats = net->can.pkg_stats; @@ -650,13 +660,11 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev) /* update statistics */ atomic_long_inc(&pkg_stats->rx_frames); atomic_long_inc(&pkg_stats->rx_frames_delta); - /* create non-zero unique skb identifier together with *skb */ - while (!(can_skb_prv(skb)->skbcnt)) - can_skb_prv(skb)->skbcnt = atomic_inc_return(&skbcounter); + can_set_skb_uid(skb); rcu_read_lock(); /* deliver the packet to sockets listening on all devices */ matches = can_rcv_filter(net->can.rx_alldev_list, skb); diff --git a/net/can/bcm.c b/net/can/bcm.c index 76bc7f727425..a819872fddef 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -348,11 +348,10 @@ static void bcm_can_tx(struct bcm_op *op, struct canfd_frame *cf) if (!skb) goto out; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; skb_put_data(skb, cf, op->cfsiz); /* send with loopback */ skb->dev = dev; @@ -1619,11 +1618,10 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk, kfree_skb(skb); return -ENODEV; } can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; skb->dev = dev; can_skb_set_owner(skb, sk); err = can_send(skb, 1); /* send with loopback */ dev_put(dev); diff --git a/net/can/isotp.c b/net/can/isotp.c index c21d816a5274..0f635680848f 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -231,11 +231,10 @@ static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus) return 1; } can_skb_reserve(nskb); can_skb_prv(nskb)->ifindex = dev->ifindex; - can_skb_prv(nskb)->skbcnt = 0; nskb->dev = dev; can_skb_set_owner(nskb, sk); ncf = (struct canfd_frame *)nskb->data; skb_put_zero(nskb, so->ll.mtu); @@ -798,11 +797,10 @@ static void isotp_send_cframe(struct isotp_sock *so) return; } can_skb_reserve(skb); can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; cf = (struct canfd_frame *)skb->data; skb_put_zero(skb, so->ll.mtu); /* create consecutive frame */ @@ -1104,11 +1102,10 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) goto err_out_drop; } can_skb_reserve(skb); can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; so->tx.len = size; so->tx.idx = 0; cf = (struct canfd_frame *)skb->data; diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c index e3ba2e9fc0e9..e56d8134938e 100644 --- a/net/can/j1939/socket.c +++ b/net/can/j1939/socket.c @@ -895,11 +895,10 @@ static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev, if (!skb) goto failure; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = ndev->ifindex; - can_skb_prv(skb)->skbcnt = 0; skb_reserve(skb, offsetof(struct can_frame, data)); ret = memcpy_from_msg(skb_put(skb, size), msg, size); if (ret < 0) goto free_skb; diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c index 9ec929bc0c0d..cadb3d3756ec 100644 --- a/net/can/j1939/transport.c +++ b/net/can/j1939/transport.c @@ -610,11 +610,10 @@ sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, return ERR_PTR(-ENOMEM); skb->dev = priv->ndev; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = priv->ndev->ifindex; - can_skb_prv(skb)->skbcnt = 0; /* reserve CAN header */ skb_reserve(skb, offsetof(struct can_frame, data)); /* skb->cb must be large enough to hold a j1939_sk_buff_cb structure */ BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*re_skcb)); @@ -1545,11 +1544,10 @@ j1939_session *j1939_session_fresh_new(struct j1939_priv *priv, return NULL; skb->dev = priv->ndev; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = priv->ndev->ifindex; - can_skb_prv(skb)->skbcnt = 0; skcb = j1939_skb_to_cb(skb); memcpy(skcb, rel_skcb, sizeof(*skcb)); session = j1939_session_new(priv, skb, size); if (!session) { diff --git a/net/can/raw.c b/net/can/raw.c index 365559d19dc3..c397071bfa8b 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -74,11 +74,11 @@ MODULE_ALIAS("can-proto-1"); * storing the single filter in dfilter, to avoid using dynamic memory. */ struct uniqframe { const struct sk_buff *skb; - int skbcnt; + u32 hash; unsigned int join_rx_count; }; struct raw_sock { struct sock sk; @@ -162,21 +162,21 @@ static void raw_rcv(struct sk_buff *oskb, void *data) } } /* eliminate multiple filter matches for the same skb */ if (this_cpu_ptr(ro->uniq)->skb == oskb && - this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { + this_cpu_ptr(ro->uniq)->hash == oskb->hash) { if (!ro->join_filters) return; this_cpu_inc(ro->uniq->join_rx_count); /* drop frame until all enabled filters matched */ if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) return; } else { this_cpu_ptr(ro->uniq)->skb = oskb; - this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; + this_cpu_ptr(ro->uniq)->hash = oskb->hash; this_cpu_ptr(ro->uniq)->join_rx_count = 1; /* drop first frame to check all enabled filters? */ if (ro->join_filters && ro->count > 1) return; } @@ -952,11 +952,10 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) if (!skb) goto put_dev; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; /* fill the skb before testing for valid CAN frames */ err = memcpy_from_msg(skb_put(skb, size), msg, size); if (err < 0) goto free_skb; -- 2.53.0