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charset="us-ascii" commit d4fb6514ff8ed6912a71294e6b66a5d59ee88007 upstream. 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 -- drivers/net/can/slcan.c | 1 - include/linux/can/core.h | 1 + include/linux/can/skb.h | 3 --- 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 +++---- 10 files changed, 15 insertions(+), 21 deletions(-) diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index e59d5cbb644a..ec624cfc1b07 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -201,11 +201,10 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf) 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; } @@ -232,11 +231,10 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev, 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; } diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c index d42ec7d1bc14..2ace2b735c20 100644 --- a/drivers/net/can/slcan.c +++ b/drivers/net/can/slcan.c @@ -211,11 +211,10 @@ static void slc_bump(struct slcan *sl) skb->pkt_type = PACKET_BROADCAST; skb->ip_summed = CHECKSUM_UNNECESSARY; can_skb_reserve(skb); can_skb_prv(skb)->ifindex = sl->dev->ifindex; - can_skb_prv(skb)->skbcnt = 0; skb_put_data(skb, &cf, sizeof(struct can_frame)); sl->dev->stats.rx_packets++; sl->dev->stats.rx_bytes += cf.len; 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 d311bc369a39..f887eb21e178 100644 --- a/include/linux/can/skb.h +++ b/include/linux/can/skb.h @@ -41,17 +41,15 @@ struct sk_buff *alloc_can_err_skb(struct net_device *dev, */ /** * 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) @@ -105,11 +103,10 @@ static inline bool can_skb_headroom_valid(struct net_device *dev, /* 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/net/can/af_can.c b/net/can/af_can.c index 85b01dea76df..95b7cc548675 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 2cf63940f6a9..235156223394 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -336,11 +336,10 @@ 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; @@ -1575,11 +1574,10 @@ 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 34939744dd41..b6b301f54e31 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -216,11 +216,10 @@ 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); @@ -771,11 +770,10 @@ 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 */ @@ -1067,11 +1065,10 @@ 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 ec2927566cf3..540836c4964d 100644 --- a/net/can/j1939/socket.c +++ b/net/can/j1939/socket.c @@ -887,11 +887,10 @@ 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 55bbcf73c873..74638cf04172 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)); @@ -1549,11 +1548,10 @@ 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 b489689ada33..ffbb622f8842 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -72,12 +72,12 @@ MODULE_ALIAS("can-proto-1"); * list containing only one item. This common case is optimized by * storing the single filter in dfilter, to avoid using dynamic memory. */ struct uniqframe { - int skbcnt; const struct sk_buff *skb; + u32 hash; unsigned int join_rx_count; }; struct raw_sock { struct sock sk; @@ -134,22 +134,22 @@ static void raw_rcv(struct sk_buff *oskb, void *data) if (!ro->fd_frames && oskb->len != CAN_MTU) return; /* 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) { 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 { 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; } @@ -827,11 +827,10 @@ 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; err = memcpy_from_msg(skb_put(skb, size), msg, size); if (err < 0) goto free_skb; -- 2.53.0