summaryrefslogtreecommitdiff
path: root/net/can/bcm.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/can/bcm.c')
-rw-r--r--net/can/bcm.c175
1 files changed, 126 insertions, 49 deletions
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 9168114fc87f..6bc1cc4c94c5 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) ? \
@@ -120,6 +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 {
@@ -138,6 +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;
@@ -205,7 +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;
@@ -261,6 +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 */
@@ -273,13 +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? */
@@ -300,6 +324,10 @@ static void bcm_can_tx(struct bcm_op *op)
skb->dev = dev;
can_skb_set_owner(skb, op->sk);
err = can_send(skb, 1);
+
+ /* update currframe and count under lock protection */
+ spin_lock_bh(&op->bcm_tx_lock);
+
if (!err)
op->frames_abs++;
@@ -308,6 +336,11 @@ static void bcm_can_tx(struct bcm_op *op)
/* 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);
}
@@ -325,6 +358,7 @@ 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;
skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
if (!skb)
@@ -332,6 +366,14 @@ 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);
@@ -344,8 +386,14 @@ 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) {
@@ -360,7 +408,6 @@ 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;
@@ -404,7 +451,7 @@ 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 */
@@ -419,7 +466,6 @@ 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);
@@ -444,7 +490,7 @@ 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;
@@ -465,13 +511,17 @@ 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 */
@@ -508,7 +558,8 @@ 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;
@@ -521,7 +572,7 @@ 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;
}
@@ -529,7 +580,7 @@ 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;
}
}
@@ -537,7 +588,7 @@ 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;
}
}
@@ -644,6 +695,7 @@ 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;
@@ -673,15 +725,24 @@ 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;
}
@@ -698,7 +759,8 @@ 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;
}
}
@@ -801,7 +863,7 @@ 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);
+ list_del_rcu(&op->list);
bcm_remove_op(op);
return 1; /* done */
}
@@ -821,7 +883,7 @@ 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 */
}
@@ -914,6 +976,27 @@ 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 */
@@ -921,9 +1004,14 @@ 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) {
@@ -969,35 +1057,20 @@ 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);
@@ -1014,11 +1087,8 @@ 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);
@@ -1150,13 +1220,10 @@ 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);
@@ -1234,7 +1301,7 @@ 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;
}
@@ -1428,6 +1495,12 @@ 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;
@@ -1577,6 +1650,7 @@ 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;
@@ -1675,6 +1749,9 @@ 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;
generated by cgit (git 2.34.1) at 2025-07-30 08:20:00 +0000