lkml.org 
[lkml]   [2017]   [Jun]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v3 08/18] xen/pvcalls: implement connect command
    From
    Date
    On 02/06/17 21:31, Stefano Stabellini wrote:
    > Allocate a socket. Keep track of socket <-> ring mappings with a new data
    > structure, called sock_mapping. Implement the connect command by calling
    > inet_stream_connect, and mapping the new indexes page and data ring.
    > Allocate a workqueue and a work_struct, called ioworker, to perform
    > reads and writes to the socket.
    >
    > When an active socket is closed (sk_state_change), set in_error to
    > -ENOTCONN and notify the other end, as specified by the protocol.
    >
    > sk_data_ready and pvcalls_back_ioworker will be implemented later.
    >
    > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
    > CC: boris.ostrovsky@oracle.com
    > CC: jgross@suse.com
    > ---
    > drivers/xen/pvcalls-back.c | 170 +++++++++++++++++++++++++++++++++++++++++++++
    > 1 file changed, 170 insertions(+)
    >
    > diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
    > index 1f2bb26..3eb84ef 100644
    > --- a/drivers/xen/pvcalls-back.c
    > +++ b/drivers/xen/pvcalls-back.c
    > @@ -56,6 +56,40 @@ struct pvcalls_fedata {
    > struct work_struct register_work;
    > };
    >
    > +struct pvcalls_ioworker {
    > + struct work_struct register_work;
    > + struct workqueue_struct *wq;
    > + unsigned int cpu;
    > +};
    > +
    > +struct sock_mapping {
    > + struct list_head list;
    > + struct pvcalls_fedata *priv;
    > + struct socket *sock;
    > + uint64_t id;
    > + grant_ref_t ref;
    > + struct pvcalls_data_intf *ring;
    > + void *bytes;
    > + struct pvcalls_data data;
    > + uint32_t ring_order;
    > + int irq;
    > + atomic_t read;
    > + atomic_t write;
    > + atomic_t io;
    > + atomic_t release;
    > + void (*saved_data_ready)(struct sock *sk);
    > + struct pvcalls_ioworker ioworker;
    > +};
    > +
    > +static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map);
    > +static int pvcalls_back_release_active(struct xenbus_device *dev,
    > + struct pvcalls_fedata *priv,
    > + struct sock_mapping *map);
    > +
    > +static void pvcalls_back_ioworker(struct work_struct *work)
    > +{
    > +}
    > +
    > static int pvcalls_back_socket(struct xenbus_device *dev,
    > struct xen_pvcalls_request *req)
    > {
    > @@ -84,9 +118,140 @@ static int pvcalls_back_socket(struct xenbus_device *dev,
    > return ret;
    > }
    >
    > +static void pvcalls_sk_state_change(struct sock *sock)
    > +{
    > + struct sock_mapping *map = sock->sk_user_data;
    > + struct pvcalls_data_intf *intf;
    > +
    > + if (map == NULL)
    > + return;
    > +
    > + intf = map->ring;
    > + intf->in_error = -ENOTCONN;
    > + notify_remote_via_irq(map->irq);
    > +}
    > +
    > +static void pvcalls_sk_data_ready(struct sock *sock)
    > +{
    > +}
    > +
    > +static struct sock_mapping *pvcalls_new_active_socket(
    > + struct pvcalls_fedata *priv,
    > + uint64_t id,
    > + grant_ref_t ref,
    > + uint32_t evtchn,
    > + struct socket *sock)
    > +{
    > + int ret;
    > + struct sock_mapping *map = NULL;

    Pointless initializer.

    > + void *page;
    > +
    > + map = kzalloc(sizeof(*map), GFP_KERNEL);
    > + if (map == NULL)
    > + return NULL;
    > +
    > + map->priv = priv;
    > + map->sock = sock;
    > + map->id = id;
    > + map->ref = ref;
    > +
    > + ret = xenbus_map_ring_valloc(priv->dev, &ref, 1, &page);
    > + if (ret < 0)
    > + goto out;
    > + map->ring = page;
    > + map->ring_order = map->ring->ring_order;
    > + /* first read the order, then map the data ring */
    > + virt_rmb();
    > + if (map->ring_order > MAX_RING_ORDER)

    Issue a message?

    > + goto out;
    > + ret = xenbus_map_ring_valloc(priv->dev, map->ring->ref,
    > + (1 << map->ring_order), &page);
    > + if (ret < 0)
    > + goto out;
    > + map->bytes = page;
    > +
    > + ret = bind_interdomain_evtchn_to_irqhandler(priv->dev->otherend_id,
    > + evtchn,
    > + pvcalls_back_conn_event,
    > + 0,
    > + "pvcalls-backend",
    > + map);
    > + if (ret < 0)
    > + goto out;
    > + map->irq = ret;
    > +
    > + map->data.in = map->bytes;
    > + map->data.out = map->bytes + XEN_FLEX_RING_SIZE(map->ring_order);
    > +
    > + map->ioworker.wq = alloc_workqueue("pvcalls_io", WQ_UNBOUND, 1);
    > + if (!map->ioworker.wq)
    > + goto out;
    > + map->ioworker.cpu = get_random_int() % num_online_cpus();

    So you expect all cpus [0..num_online_cpus()[ to be online. I don't
    think this is always true.

    > + atomic_set(&map->io, 1);
    > + INIT_WORK(&map->ioworker.register_work, pvcalls_back_ioworker);
    > +
    > + down(&priv->socket_lock);
    > + list_add_tail(&map->list, &priv->socket_mappings);
    > + up(&priv->socket_lock);
    > +
    > + write_lock_bh(&map->sock->sk->sk_callback_lock);
    > + map->saved_data_ready = map->sock->sk->sk_data_ready;
    > + map->sock->sk->sk_user_data = map;
    > + map->sock->sk->sk_data_ready = pvcalls_sk_data_ready;
    > + map->sock->sk->sk_state_change = pvcalls_sk_state_change;
    > + write_unlock_bh(&map->sock->sk->sk_callback_lock);
    > +
    > + return map;
    > +out:
    > + pvcalls_back_release_active(priv->dev, priv, map);
    > + return NULL;
    > +}
    > +
    > static int pvcalls_back_connect(struct xenbus_device *dev,
    > struct xen_pvcalls_request *req)
    > {
    > + struct pvcalls_fedata *priv;
    > + int ret;
    > + struct socket *sock;
    > + struct sock_mapping *map = NULL;
    > + struct xen_pvcalls_response *rsp;
    > +
    > + priv = dev_get_drvdata(&dev->dev);
    > +
    > + ret = sock_create(AF_INET, SOCK_STREAM, 0, &sock);
    > + if (ret < 0)
    > + goto out;
    > + ret = inet_stream_connect(sock, (struct sockaddr *)&req->u.connect.addr,
    > + req->u.connect.len, req->u.connect.flags);
    > + if (ret < 0) {
    > + sock_release(map->sock);
    > + goto out;
    > + }
    > +
    > + map = pvcalls_new_active_socket(priv,
    > + req->u.connect.id,
    > + req->u.connect.ref,
    > + req->u.connect.evtchn,
    > + sock);
    > + if (!map) {
    > + sock_release(map->sock);
    > + goto out;

    ret will be 0 here. So there was a failure and you report success.


    Juergen

    > + }
    > +
    > +out:
    > + rsp = RING_GET_RESPONSE(&priv->ring, priv->ring.rsp_prod_pvt++);
    > + rsp->req_id = req->req_id;
    > + rsp->cmd = req->cmd;
    > + rsp->u.connect.id = req->u.connect.id;
    > + rsp->ret = ret;
    > +
    > + return ret;
    > +}
    > +
    > +static int pvcalls_back_release_active(struct xenbus_device *dev,
    > + struct pvcalls_fedata *priv,
    > + struct sock_mapping *map)
    > +{
    > return 0;
    > }
    >
    > @@ -206,6 +371,11 @@ static irqreturn_t pvcalls_back_event(int irq, void *dev_id)
    > return IRQ_HANDLED;
    > }
    >
    > +static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map)
    > +{
    > + return IRQ_HANDLED;
    > +}
    > +
    > static int backend_connect(struct xenbus_device *dev)
    > {
    > int err, evtchn;
    >

    \
     
     \ /
      Last update: 2017-06-13 08:18    [W:4.061 / U:0.248 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site