[PATCH v3 07/13] xen/pvcalls: implement listen command

From: Stefano Stabellini
Date: Mon Jul 31 2017 - 18:57:48 EST


Send PVCALLS_LISTEN to the backend.

Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
CC: boris.ostrovsky@xxxxxxxxxx
CC: jgross@xxxxxxxx
---
drivers/xen/pvcalls-front.c | 47 +++++++++++++++++++++++++++++++++++++++++++++
drivers/xen/pvcalls-front.h | 1 +
2 files changed, 48 insertions(+)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 5ccef34..b2757f5 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -367,6 +367,53 @@ int pvcalls_front_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
return 0;
}

+int pvcalls_front_listen(struct socket *sock, int backlog)
+{
+ struct pvcalls_bedata *bedata;
+ struct sock_mapping *map;
+ struct xen_pvcalls_request *req;
+ int notify, req_id, ret;
+
+ if (!pvcalls_front_dev)
+ return -ENOTCONN;
+ bedata = dev_get_drvdata(&pvcalls_front_dev->dev);
+
+ map = (struct sock_mapping *) READ_ONCE(sock->sk->sk_send_head);
+ if (!map)
+ return -ENOTSOCK;
+
+ if (map->passive.status != PVCALLS_STATUS_BIND)
+ return -EOPNOTSUPP;
+
+ spin_lock(&bedata->pvcallss_lock);
+ ret = get_request(bedata, &req_id);
+ if (ret < 0) {
+ spin_unlock(&bedata->pvcallss_lock);
+ return ret;
+ }
+ req = RING_GET_REQUEST(&bedata->ring, req_id);
+ req->req_id = req_id;
+ req->cmd = PVCALLS_LISTEN;
+ req->u.listen.id = (uint64_t) map;
+ req->u.listen.backlog = backlog;
+
+ bedata->ring.req_prod_pvt++;
+ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&bedata->ring, notify);
+ spin_unlock(&bedata->pvcallss_lock);
+ if (notify)
+ notify_remote_via_irq(bedata->irq);
+
+ wait_event(bedata->inflight_req,
+ READ_ONCE(bedata->rsp[req_id].req_id) == req_id);
+
+ map->passive.status = PVCALLS_STATUS_LISTEN;
+ ret = bedata->rsp[req_id].ret;
+ /* read ret, then set this rsp slot to be reused */
+ smp_mb();
+ WRITE_ONCE(bedata->rsp[req_id].req_id, PVCALLS_INVALID_ID);
+ return ret;
+}
+
static const struct xenbus_device_id pvcalls_front_ids[] = {
{ "pvcalls" },
{ "" }
diff --git a/drivers/xen/pvcalls-front.h b/drivers/xen/pvcalls-front.h
index 8b0a274..aa8fe10 100644
--- a/drivers/xen/pvcalls-front.h
+++ b/drivers/xen/pvcalls-front.h
@@ -9,5 +9,6 @@ int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr,
int pvcalls_front_bind(struct socket *sock,
struct sockaddr *addr,
int addr_len);
+int pvcalls_front_listen(struct socket *sock, int backlog);

#endif
--
1.9.1