diff options
Diffstat (limited to 'net/can/bcm.c')
| -rw-r--r-- | net/can/bcm.c | 270 |
1 files changed, 188 insertions, 82 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c index 95d209b52e6a..7eba8ae01a5b 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -58,6 +58,7 @@ #include <linux/can/skb.h> #include <linux/can/bcm.h> #include <linux/slab.h> +#include <linux/spinlock.h> #include <net/sock.h> #include <net/net_namespace.h> @@ -72,9 +73,11 @@ #define BCM_TIMER_SEC_MAX (400 * 24 * 60 * 60) /* use of last_frames[index].flags */ +#define RX_LOCAL 0x10 /* frame was created on the local host */ +#define RX_OWN 0x20 /* frame was sent via the socket it was received on */ #define RX_RECV 0x40 /* received data for this element */ #define RX_THR 0x80 /* element not been sent due to throttle feature */ -#define BCM_CAN_FLAGS_MASK 0x3F /* to clean private flags after usage */ +#define BCM_CAN_FLAGS_MASK 0x0F /* to clean private flags after usage */ /* get best masking value for can_rx_register() for a given single can_id */ #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \ @@ -100,6 +103,7 @@ static inline u64 get_u64(const struct canfd_frame *cp, int offset) struct bcm_op { struct list_head list; + struct rcu_head rcu; int ifindex; canid_t can_id; u32 flags; @@ -119,6 +123,7 @@ struct bcm_op { struct canfd_frame last_sframe; struct sock *sk; struct net_device *rx_reg_dev; + spinlock_t bcm_tx_lock; /* protect currframe/count in runtime updates */ }; struct bcm_sock { @@ -137,6 +142,16 @@ static LIST_HEAD(bcm_notifier_list); static DEFINE_SPINLOCK(bcm_notifier_lock); static struct bcm_sock *bcm_busy_notifier; +/* Return pointer to store the extra msg flags for bcm_recvmsg(). + * We use the space of one unsigned int beyond the 'struct sockaddr_can' + * in skb->cb. + */ +static inline unsigned int *bcm_flags(struct sk_buff *skb) +{ + /* return pointer after struct sockaddr_can */ + return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); +} + static inline struct bcm_sock *bcm_sk(const struct sock *sk) { return (struct bcm_sock *)sk; @@ -204,7 +219,9 @@ static int bcm_proc_show(struct seq_file *m, void *v) seq_printf(m, " / bound %s", bcm_proc_getifname(net, ifname, bo->ifindex)); seq_printf(m, " <<<\n"); - list_for_each_entry(op, &bo->rx_ops, list) { + rcu_read_lock(); + + list_for_each_entry_rcu(op, &bo->rx_ops, list) { unsigned long reduction; @@ -260,6 +277,9 @@ static int bcm_proc_show(struct seq_file *m, void *v) seq_printf(m, "# sent %ld\n", op->frames_abs); } seq_putc(m, '\n'); + + rcu_read_unlock(); + return 0; } #endif /* CONFIG_PROC_FS */ @@ -272,12 +292,18 @@ static void bcm_can_tx(struct bcm_op *op) { struct sk_buff *skb; struct net_device *dev; - struct canfd_frame *cf = op->frames + op->cfsiz * op->currframe; + struct canfd_frame *cf; + int err; /* no target device? => exit */ if (!op->ifindex) return; + /* read currframe under lock protection */ + spin_lock_bh(&op->bcm_tx_lock); + cf = op->frames + op->cfsiz * op->currframe; + spin_unlock_bh(&op->bcm_tx_lock); + dev = dev_get_by_index(sock_net(op->sk), op->ifindex); if (!dev) { /* RFC: should this bcm_op remove itself here? */ @@ -297,15 +323,24 @@ static void bcm_can_tx(struct bcm_op *op) /* send with loopback */ skb->dev = dev; can_skb_set_owner(skb, op->sk); - can_send(skb, 1); + err = can_send(skb, 1); + + /* update currframe and count under lock protection */ + spin_lock_bh(&op->bcm_tx_lock); + + if (!err) + op->frames_abs++; - /* update statistics */ op->currframe++; - op->frames_abs++; /* reached last frame? */ if (op->currframe >= op->nframes) op->currframe = 0; + + if (op->count > 0) + op->count--; + + spin_unlock_bh(&op->bcm_tx_lock); out: dev_put(dev); } @@ -323,6 +358,8 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, struct sock *sk = op->sk; unsigned int datalen = head->nframes * op->cfsiz; int err; + unsigned int *pflags; + enum skb_drop_reason reason; skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); if (!skb) @@ -330,6 +367,14 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, skb_put_data(skb, head, sizeof(*head)); + /* ensure space for sockaddr_can and msg flags */ + sock_skb_cb_check_size(sizeof(struct sockaddr_can) + + sizeof(unsigned int)); + + /* initialize msg flags */ + pflags = bcm_flags(skb); + *pflags = 0; + if (head->nframes) { /* CAN frames starting here */ firstframe = (struct canfd_frame *)skb_tail_pointer(skb); @@ -342,8 +387,14 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, * relevant for updates that are generated by the * BCM, where nframes is 1 */ - if (head->nframes == 1) + if (head->nframes == 1) { + if (firstframe->flags & RX_LOCAL) + *pflags |= MSG_DONTROUTE; + if (firstframe->flags & RX_OWN) + *pflags |= MSG_CONFIRM; + firstframe->flags &= BCM_CAN_FLAGS_MASK; + } } if (has_timestamp) { @@ -358,17 +409,16 @@ static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, * containing the interface index. */ - sock_skb_cb_check_size(sizeof(struct sockaddr_can)); addr = (struct sockaddr_can *)skb->cb; memset(addr, 0, sizeof(*addr)); addr->can_family = AF_CAN; addr->can_ifindex = op->rx_ifindex; - err = sock_queue_rcv_skb(sk, skb); + err = sock_queue_rcv_skb_reason(sk, skb, &reason); if (err < 0) { struct bcm_sock *bo = bcm_sk(sk); - kfree_skb(skb); + sk_skb_reason_drop(sk, skb, reason); /* don't care about overflows in this statistic */ bo->dropped_usr_msgs++; } @@ -402,7 +452,7 @@ static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) struct bcm_msg_head msg_head; if (op->kt_ival1 && (op->count > 0)) { - op->count--; + bcm_can_tx(op); if (!op->count && (op->flags & TX_COUNTEVT)) { /* create notification to user */ @@ -417,7 +467,6 @@ static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) bcm_send_to_user(op, &msg_head, NULL, 0); } - bcm_can_tx(op); } else if (op->kt_ival2) { bcm_can_tx(op); @@ -442,7 +491,7 @@ static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data) op->frames_filtered = op->frames_abs = 0; /* this element is not throttled anymore */ - data->flags &= (BCM_CAN_FLAGS_MASK|RX_RECV); + data->flags &= ~RX_THR; memset(&head, 0, sizeof(head)); head.opcode = RX_CHANGED; @@ -463,13 +512,17 @@ static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data) */ static void bcm_rx_update_and_send(struct bcm_op *op, struct canfd_frame *lastdata, - const struct canfd_frame *rxdata) + const struct canfd_frame *rxdata, + unsigned char traffic_flags) { memcpy(lastdata, rxdata, op->cfsiz); /* mark as used and throttled by default */ lastdata->flags |= (RX_RECV|RX_THR); + /* add own/local/remote traffic flags */ + lastdata->flags |= traffic_flags; + /* throttling mode inactive ? */ if (!op->kt_ival2) { /* send RX_CHANGED to the user immediately */ @@ -506,7 +559,8 @@ rx_changed_settime: * received data stored in op->last_frames[] */ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, - const struct canfd_frame *rxdata) + const struct canfd_frame *rxdata, + unsigned char traffic_flags) { struct canfd_frame *cf = op->frames + op->cfsiz * index; struct canfd_frame *lcf = op->last_frames + op->cfsiz * index; @@ -519,7 +573,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, if (!(lcf->flags & RX_RECV)) { /* received data for the first time => send update to user */ - bcm_rx_update_and_send(op, lcf, rxdata); + bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags); return; } @@ -527,7 +581,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, for (i = 0; i < rxdata->len; i += 8) { if ((get_u64(cf, i) & get_u64(rxdata, i)) != (get_u64(cf, i) & get_u64(lcf, i))) { - bcm_rx_update_and_send(op, lcf, rxdata); + bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags); return; } } @@ -535,7 +589,7 @@ static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, if (op->flags & RX_CHECK_DLC) { /* do a real check in CAN frame length */ if (rxdata->len != lcf->len) { - bcm_rx_update_and_send(op, lcf, rxdata); + bcm_rx_update_and_send(op, lcf, rxdata, traffic_flags); return; } } @@ -642,13 +696,19 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data) struct bcm_op *op = (struct bcm_op *)data; const struct canfd_frame *rxframe = (struct canfd_frame *)skb->data; unsigned int i; + unsigned char traffic_flags; if (op->can_id != rxframe->can_id) return; /* make sure to handle the correct frame type (CAN / CAN FD) */ - if (skb->len != op->cfsiz) - return; + if (op->flags & CAN_FD_FRAME) { + if (!can_is_canfd_skb(skb)) + return; + } else { + if (!can_is_can_skb(skb)) + return; + } /* disable timeout */ hrtimer_cancel(&op->timer); @@ -666,15 +726,24 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data) return; } + /* compute flags to distinguish between own/local/remote CAN traffic */ + traffic_flags = 0; + if (skb->sk) { + traffic_flags |= RX_LOCAL; + if (skb->sk == op->sk) + traffic_flags |= RX_OWN; + } + if (op->flags & RX_FILTER_ID) { /* the easiest case */ - bcm_rx_update_and_send(op, op->last_frames, rxframe); + bcm_rx_update_and_send(op, op->last_frames, rxframe, + traffic_flags); goto rx_starttimer; } if (op->nframes == 1) { /* simple compare with index 0 */ - bcm_rx_cmp_to_index(op, 0, rxframe); + bcm_rx_cmp_to_index(op, 0, rxframe, traffic_flags); goto rx_starttimer; } @@ -691,7 +760,8 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data) if ((get_u64(op->frames, 0) & get_u64(rxframe, 0)) == (get_u64(op->frames, 0) & get_u64(op->frames + op->cfsiz * i, 0))) { - bcm_rx_cmp_to_index(op, i, rxframe); + bcm_rx_cmp_to_index(op, i, rxframe, + traffic_flags); break; } } @@ -718,10 +788,9 @@ static struct bcm_op *bcm_find_op(struct list_head *ops, return NULL; } -static void bcm_remove_op(struct bcm_op *op) +static void bcm_free_op_rcu(struct rcu_head *rcu_head) { - hrtimer_cancel(&op->timer); - hrtimer_cancel(&op->thrtimer); + struct bcm_op *op = container_of(rcu_head, struct bcm_op, rcu); if ((op->frames) && (op->frames != &op->sframe)) kfree(op->frames); @@ -732,6 +801,14 @@ static void bcm_remove_op(struct bcm_op *op) kfree(op); } +static void bcm_remove_op(struct bcm_op *op) +{ + hrtimer_cancel(&op->timer); + hrtimer_cancel(&op->thrtimer); + + call_rcu(&op->rcu, bcm_free_op_rcu); +} + static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) { if (op->rx_reg_dev == dev) { @@ -757,6 +834,9 @@ static int bcm_delete_rx_op(struct list_head *ops, struct bcm_msg_head *mh, if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) && (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) { + /* disable automatic timer on frame reception */ + op->flags |= RX_NO_AUTOTIMER; + /* * Don't care if we're bound or not (due to netdev * problems) can_rx_unregister() is always a save @@ -784,8 +864,7 @@ static int bcm_delete_rx_op(struct list_head *ops, struct bcm_msg_head *mh, REGMASK(op->can_id), bcm_rx_handler, op); - list_del(&op->list); - synchronize_rcu(); + list_del_rcu(&op->list); bcm_remove_op(op); return 1; /* done */ } @@ -805,7 +884,7 @@ static int bcm_delete_tx_op(struct list_head *ops, struct bcm_msg_head *mh, list_for_each_entry_safe(op, n, ops, list) { if ((op->can_id == mh->can_id) && (op->ifindex == ifindex) && (op->flags & CAN_FD_FRAME) == (mh->flags & CAN_FD_FRAME)) { - list_del(&op->list); + list_del_rcu(&op->list); bcm_remove_op(op); return 1; /* done */ } @@ -898,6 +977,27 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, } op->flags = msg_head->flags; + /* only lock for unlikely count/nframes/currframe changes */ + if (op->nframes != msg_head->nframes || + op->flags & TX_RESET_MULTI_IDX || + op->flags & SETTIMER) { + + spin_lock_bh(&op->bcm_tx_lock); + + if (op->nframes != msg_head->nframes || + op->flags & TX_RESET_MULTI_IDX) { + /* potentially update changed nframes */ + op->nframes = msg_head->nframes; + /* restart multiple frame transmission */ + op->currframe = 0; + } + + if (op->flags & SETTIMER) + op->count = msg_head->count; + + spin_unlock_bh(&op->bcm_tx_lock); + } + } else { /* insert new BCM operation for the given can_id */ @@ -905,9 +1005,14 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, if (!op) return -ENOMEM; + spin_lock_init(&op->bcm_tx_lock); op->can_id = msg_head->can_id; op->cfsiz = CFSIZ(msg_head->flags); op->flags = msg_head->flags; + op->nframes = msg_head->nframes; + + if (op->flags & SETTIMER) + op->count = msg_head->count; /* create array for CAN frames and copy the data */ if (msg_head->nframes > 1) { @@ -925,6 +1030,8 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, cf = op->frames + op->cfsiz * i; err = memcpy_from_msg((u8 *)cf, msg, op->cfsiz); + if (err < 0) + goto free_op; if (op->flags & CAN_FD_FRAME) { if (cf->len > 64) @@ -934,12 +1041,8 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, err = -EINVAL; } - if (err < 0) { - if (op->frames != &op->sframe) - kfree(op->frames); - kfree(op); - return err; - } + if (err < 0) + goto free_op; if (msg_head->flags & TX_CP_CAN_ID) { /* copy can_id into frame */ @@ -955,35 +1058,20 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, op->ifindex = ifindex; /* initialize uninitialized (kzalloc) structure */ - hrtimer_init(&op->timer, CLOCK_MONOTONIC, - HRTIMER_MODE_REL_SOFT); - op->timer.function = bcm_tx_timeout_handler; + hrtimer_setup(&op->timer, bcm_tx_timeout_handler, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); /* currently unused in tx_ops */ - hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, - HRTIMER_MODE_REL_SOFT); + hrtimer_setup(&op->thrtimer, hrtimer_dummy_timeout, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); /* add this bcm_op to the list of the tx_ops */ list_add(&op->list, &bo->tx_ops); } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ - if (op->nframes != msg_head->nframes) { - op->nframes = msg_head->nframes; - /* start multiple frame transmission with index 0 */ - op->currframe = 0; - } - - /* check flags */ - - if (op->flags & TX_RESET_MULTI_IDX) { - /* start multiple frame transmission with index 0 */ - op->currframe = 0; - } - if (op->flags & SETTIMER) { /* set timer values */ - op->count = msg_head->count; op->ival1 = msg_head->ival1; op->ival2 = msg_head->ival2; op->kt_ival1 = bcm_timeval_to_ktime(msg_head->ival1); @@ -1000,16 +1088,19 @@ static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, op->flags |= TX_ANNOUNCE; } - if (op->flags & TX_ANNOUNCE) { + if (op->flags & TX_ANNOUNCE) bcm_can_tx(op); - if (op->count) - op->count--; - } if (op->flags & STARTTIMER) bcm_tx_start_timer(op); return msg_head->nframes * op->cfsiz + MHSIZ; + +free_op: + if (op->frames != &op->sframe) + kfree(op->frames); + kfree(op); + return err; } /* @@ -1130,13 +1221,10 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, op->rx_ifindex = ifindex; /* initialize uninitialized (kzalloc) structure */ - hrtimer_init(&op->timer, CLOCK_MONOTONIC, - HRTIMER_MODE_REL_SOFT); - op->timer.function = bcm_rx_timeout_handler; - - hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, - HRTIMER_MODE_REL_SOFT); - op->thrtimer.function = bcm_rx_thr_handler; + hrtimer_setup(&op->timer, bcm_rx_timeout_handler, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + hrtimer_setup(&op->thrtimer, bcm_rx_thr_handler, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); /* add this bcm_op to the list of the rx_ops */ list_add(&op->list, &bo->rx_ops); @@ -1214,7 +1302,7 @@ static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, bcm_rx_handler, op, "bcm", sk); if (err) { /* this bcm rx op is broken -> remove it */ - list_del(&op->list); + list_del_rcu(&op->list); bcm_remove_op(op); return err; } @@ -1408,6 +1496,12 @@ static void bcm_notify(struct bcm_sock *bo, unsigned long msg, /* remove device reference, if this is our bound device */ if (bo->bound && bo->ifindex == dev->ifindex) { +#if IS_ENABLED(CONFIG_PROC_FS) + if (sock_net(sk)->can.bcmproc_dir && bo->bcm_proc_read) { + remove_proc_entry(bo->procname, sock_net(sk)->can.bcmproc_dir); + bo->bcm_proc_read = NULL; + } +#endif bo->bound = 0; bo->ifindex = 0; notify_enodev = 1; @@ -1506,6 +1600,12 @@ static int bcm_release(struct socket *sock) lock_sock(sk); +#if IS_ENABLED(CONFIG_PROC_FS) + /* remove procfs entry */ + if (net->can.bcmproc_dir && bo->bcm_proc_read) + remove_proc_entry(bo->procname, net->can.bcmproc_dir); +#endif /* CONFIG_PROC_FS */ + list_for_each_entry_safe(op, next, &bo->tx_ops, list) bcm_remove_op(op); @@ -1541,12 +1641,6 @@ static int bcm_release(struct socket *sock) list_for_each_entry_safe(op, next, &bo->rx_ops, list) bcm_remove_op(op); -#if IS_ENABLED(CONFIG_PROC_FS) - /* remove procfs entry */ - if (net->can.bcmproc_dir && bo->bcm_proc_read) - remove_proc_entry(bo->procname, net->can.bcmproc_dir); -#endif /* CONFIG_PROC_FS */ - /* remove device reference */ if (bo->bound) { bo->bound = 0; @@ -1557,12 +1651,13 @@ static int bcm_release(struct socket *sock) sock->sk = NULL; release_sock(sk); + sock_prot_inuse_add(net, sk->sk_prot, -1); sock_put(sk); return 0; } -static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, +static int bcm_connect(struct socket *sock, struct sockaddr_unsized *uaddr, int len, int flags) { struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; @@ -1632,12 +1727,9 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, struct sock *sk = sock->sk; struct sk_buff *skb; int error = 0; - int noblock; int err; - noblock = flags & MSG_DONTWAIT; - flags &= ~MSG_DONTWAIT; - skb = skb_recv_datagram(sk, flags, noblock, &error); + skb = skb_recv_datagram(sk, flags, &error); if (!skb) return error; @@ -1650,7 +1742,7 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, return err; } - sock_recv_ts_and_drops(msg, sk, skb); + sock_recv_cmsgs(msg, sk, skb); if (msg->msg_name) { __sockaddr_check_size(BCM_MIN_NAMELEN); @@ -1658,6 +1750,9 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, memcpy(msg->msg_name, skb->cb, msg->msg_namelen); } + /* assign the flags that have been recorded in bcm_send_to_user() */ + msg->msg_flags |= *(bcm_flags(skb)); + skb_free_datagram(sk, skb); return size; @@ -1686,7 +1781,6 @@ static const struct proto_ops bcm_ops = { .sendmsg = bcm_sendmsg, .recvmsg = bcm_recvmsg, .mmap = sock_no_mmap, - .sendpage = sock_no_sendpage, }; static struct proto bcm_proto __read_mostly = { @@ -1737,15 +1831,27 @@ static int __init bcm_module_init(void) pr_info("can: broadcast manager protocol\n"); + err = register_pernet_subsys(&canbcm_pernet_ops); + if (err) + return err; + + err = register_netdevice_notifier(&canbcm_notifier); + if (err) + goto register_notifier_failed; + err = can_proto_register(&bcm_can_proto); if (err < 0) { printk(KERN_ERR "can: registration of bcm protocol failed\n"); - return err; + goto register_proto_failed; } - register_pernet_subsys(&canbcm_pernet_ops); - register_netdevice_notifier(&canbcm_notifier); return 0; + +register_proto_failed: + unregister_netdevice_notifier(&canbcm_notifier); +register_notifier_failed: + unregister_pernet_subsys(&canbcm_pernet_ops); + return err; } static void __exit bcm_module_exit(void) |
