diff options
| -rw-r--r-- | drivers/xen/pvcalls-back.c | 75 |
1 files changed, 74 insertions, 1 deletions
diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index 9a4bdc5e5d34..06bd95d4d552 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -355,11 +355,34 @@ out_error: static void pvcalls_pass_sk_data_ready(struct sock *sock) { struct sockpass_mapping *mappass = sock->sk_user_data; + struct pvcalls_fedata *fedata; + struct xen_pvcalls_response *rsp; + unsigned long flags; + int notify; if (mappass == NULL) return; - queue_work(mappass->wq, &mappass->register_work); + fedata = mappass->fedata; + spin_lock_irqsave(&mappass->copy_lock, flags); + if (mappass->reqcopy.cmd == PVCALLS_POLL) { + rsp = RING_GET_RESPONSE(&fedata->ring, + fedata->ring.rsp_prod_pvt++); + rsp->req_id = mappass->reqcopy.req_id; + rsp->u.poll.id = mappass->reqcopy.u.poll.id; + rsp->cmd = mappass->reqcopy.cmd; + rsp->ret = 0; + + mappass->reqcopy.cmd = 0; + spin_unlock_irqrestore(&mappass->copy_lock, flags); + + RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&fedata->ring, notify); + if (notify) + notify_remote_via_irq(mappass->fedata->irq); + } else { + spin_unlock_irqrestore(&mappass->copy_lock, flags); + queue_work(mappass->wq, &mappass->register_work); + } } static int pvcalls_back_bind(struct xenbus_device *dev, @@ -502,6 +525,56 @@ out_error: static int pvcalls_back_poll(struct xenbus_device *dev, struct xen_pvcalls_request *req) { + struct pvcalls_fedata *fedata; + struct sockpass_mapping *mappass; + struct xen_pvcalls_response *rsp; + struct inet_connection_sock *icsk; + struct request_sock_queue *queue; + unsigned long flags; + int ret; + bool data; + + fedata = dev_get_drvdata(&dev->dev); + + down(&fedata->socket_lock); + mappass = radix_tree_lookup(&fedata->socketpass_mappings, + req->u.poll.id); + up(&fedata->socket_lock); + if (mappass == NULL) + return -EINVAL; + + /* + * Limitation of the current implementation: only support one + * concurrent accept or poll call on one socket. + */ + spin_lock_irqsave(&mappass->copy_lock, flags); + if (mappass->reqcopy.cmd != 0) { + ret = -EINTR; + goto out; + } + + mappass->reqcopy = *req; + icsk = inet_csk(mappass->sock->sk); + queue = &icsk->icsk_accept_queue; + data = queue->rskq_accept_head != NULL; + if (data) { + mappass->reqcopy.cmd = 0; + ret = 0; + goto out; + } + spin_unlock_irqrestore(&mappass->copy_lock, flags); + + /* Tell the caller we don't need to send back a notification yet */ + return -1; + +out: + spin_unlock_irqrestore(&mappass->copy_lock, flags); + + rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); + rsp->req_id = req->req_id; + rsp->cmd = req->cmd; + rsp->u.poll.id = req->u.poll.id; + rsp->ret = ret; return 0; } |