Re: [PATCH v3 06/13] xen/pvcalls: implement bind command

From: Boris Ostrovsky
Date: Sat Aug 12 2017 - 21:23:48 EST




On 07/31/2017 06:57 PM, Stefano Stabellini wrote:
Send PVCALLS_BIND to the backend. Introduce a new structure, part of
struct sock_mapping, to store information specific to passive sockets.

Introduce a status field to keep track of the status of the passive
socket.

Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
CC: boris.ostrovsky@xxxxxxxxxx
CC: jgross@xxxxxxxx
---
drivers/xen/pvcalls-front.c | 59 +++++++++++++++++++++++++++++++++++++++++++++
drivers/xen/pvcalls-front.h | 3 +++
2 files changed, 62 insertions(+)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 379b8fb..5ccef34 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -59,6 +59,13 @@ struct sock_mapping {
wait_queue_head_t inflight_conn_req;
} active;
+ struct {
+ /* Socket status */
+#define PVCALLS_STATUS_UNINITALIZED 0
+#define PVCALLS_STATUS_BIND 1
+#define PVCALLS_STATUS_LISTEN 2
+ uint8_t status;
+ } passive;
};
};
@@ -308,6 +315,58 @@ int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr,
return ret;
}
+int pvcalls_front_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
+{
+ struct pvcalls_bedata *bedata;
+ struct sock_mapping *map = NULL;
+ struct xen_pvcalls_request *req;
+ int notify, req_id, ret;
+
+ if (!pvcalls_front_dev)
+ return -ENOTCONN;
+ if (addr->sa_family != AF_INET || sock->type != SOCK_STREAM)


No protocol check? (in the previous patch too)

-boris

+ return -ENOTSUPP;
+ bedata = dev_get_drvdata(&pvcalls_front_dev->dev);
+
+ map = (struct sock_mapping *) READ_ONCE(sock->sk->sk_send_head);
+ if (map == NULL)
+ return -EINVAL;
+
+ 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;
+ map->sock = sock;
+ req->cmd = PVCALLS_BIND;
+ req->u.bind.id = (uint64_t) map;
+ memcpy(req->u.bind.addr, addr, sizeof(*addr));
+ req->u.bind.len = addr_len;
+
+ init_waitqueue_head(&map->passive.inflight_accept_req);
+
+ map->active_socket = false;
+
+ 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_BIND;
+ 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 0;
+}
+
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 63b0417..8b0a274 100644
--- a/drivers/xen/pvcalls-front.h
+++ b/drivers/xen/pvcalls-front.h
@@ -6,5 +6,8 @@
int pvcalls_front_socket(struct socket *sock);
int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr,
int addr_len, int flags);
+int pvcalls_front_bind(struct socket *sock,
+ struct sockaddr *addr,
+ int addr_len);
#endif