struct atm_vcc *atmvcc; /* VCC descriptor */
void (*old_push)(struct atm_vcc *, struct sk_buff *);
void (*old_pop)(struct atm_vcc *, struct sk_buff *);
+ void (*old_release_cb)(struct atm_vcc *);
struct module *old_owner;
/* keep old push/pop for detaching */
enum pppoatm_encaps encaps;
ppp_output_wakeup((struct ppp_channel *) arg);
}
+static void pppoatm_release_cb(struct atm_vcc *atmvcc)
+{
+ struct pppoatm_vcc *pvcc = atmvcc_to_pvcc(atmvcc);
+
+ /*
+ * As in pppoatm_pop(), it's safe to clear the BLOCKED bit here because
+ * the wakeup *can't* race with pppoatm_send(). They both hold the PPP
+ * channel's ->downl lock. And the potential race with *setting* it,
+ * which leads to the double-check dance in pppoatm_may_send(), doesn't
+ * exist here. In the sock_owned_by_user() case in pppoatm_send(), we
+ * set the BLOCKED bit while the socket is still locked. We know that
+ * ->release_cb() can't be called until that's done.
+ */
+ if (test_and_clear_bit(BLOCKED, &pvcc->blocked))
+ tasklet_schedule(&pvcc->wakeup_tasklet);
+ if (pvcc->old_release_cb)
+ pvcc->old_release_cb(atmvcc);
+}
/*
* This gets called every time the ATM card has finished sending our
* skb. The ->old_pop will take care up normal atm flow control,
pvcc = atmvcc_to_pvcc(atmvcc);
atmvcc->push = pvcc->old_push;
atmvcc->pop = pvcc->old_pop;
+ atmvcc->release_cb = pvcc->old_release_cb;
tasklet_kill(&pvcc->wakeup_tasklet);
ppp_unregister_channel(&pvcc->chan);
atmvcc->user_back = NULL;
ppp_input_error(&pvcc->chan, 0);
}
-static inline int pppoatm_may_send(struct pppoatm_vcc *pvcc, int size)
+static int pppoatm_may_send(struct pppoatm_vcc *pvcc, int size)
{
/*
* It's not clear that we need to bother with using atm_may_send()
vcc = ATM_SKB(skb)->vcc;
bh_lock_sock(sk_atm(vcc));
- if (sock_owned_by_user(sk_atm(vcc)))
+ if (sock_owned_by_user(sk_atm(vcc))) {
+ /*
+ * Needs to happen (and be flushed, hence test_and_) before we unlock
+ * the socket. It needs to be seen by the time our ->release_cb gets
+ * called.
+ */
+ test_and_set_bit(BLOCKED, &pvcc->blocked);
goto nospace;
+ }
if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
test_bit(ATM_VF_CLOSE, &vcc->flags) ||
!test_bit(ATM_VF_READY, &vcc->flags)) {
pvcc->old_push = atmvcc->push;
pvcc->old_pop = atmvcc->pop;
pvcc->old_owner = atmvcc->owner;
+ pvcc->old_release_cb = atmvcc->release_cb;
pvcc->encaps = (enum pppoatm_encaps) be.encaps;
pvcc->chan.private = pvcc;
pvcc->chan.ops = &pppoatm_ops;
atmvcc->user_back = pvcc;
atmvcc->push = pppoatm_push;
atmvcc->pop = pppoatm_pop;
+ atmvcc->release_cb = pppoatm_release_cb;
__module_get(THIS_MODULE);
atmvcc->owner = THIS_MODULE;