Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751839AbdFUU0B (ORCPT ); Wed, 21 Jun 2017 16:26:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:60968 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751106AbdFUU0A (ORCPT ); Wed, 21 Jun 2017 16:26:00 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9E992187B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=sstabellini@kernel.org Date: Wed, 21 Jun 2017 13:25:55 -0700 (PDT) From: Stefano Stabellini X-X-Sender: sstabellini@sstabellini-ThinkPad-X260 To: Boris Ostrovsky cc: Stefano Stabellini , xen-devel@lists.xen.org, linux-kernel@vger.kernel.org, jgross@suse.com, Stefano Stabellini Subject: Re: [PATCH v4 08/18] xen/pvcalls: implement connect command In-Reply-To: <85f49d02-a640-6259-727d-e3761631d1b5@oracle.com> Message-ID: References: <1497553787-3709-1-git-send-email-sstabellini@kernel.org> <1497553787-3709-8-git-send-email-sstabellini@kernel.org> <85f49d02-a640-6259-727d-e3761631d1b5@oracle.com> User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7003 Lines: 240 On Tue, 20 Jun 2017, Boris Ostrovsky wrote: > On 06/15/2017 03:09 PM, 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 > > CC: boris.ostrovsky@oracle.com > > CC: jgross@suse.com > > --- > > drivers/xen/pvcalls-back.c | 171 +++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 171 insertions(+) > > > > diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c > > index 953458b..4eecd83 100644 > > --- a/drivers/xen/pvcalls-back.c > > +++ b/drivers/xen/pvcalls-back.c > > @@ -56,6 +56,39 @@ struct pvcalls_fedata { > > struct work_struct register_work; > > }; > > > > +struct pvcalls_ioworker { > > + struct work_struct register_work; > > + struct workqueue_struct *wq; > > +}; > > + > > +struct sock_mapping { > > + struct list_head list; > > + struct pvcalls_fedata *fedata; > > + 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 *fedata, > > + 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 +117,142 @@ static int pvcalls_back_socket(struct xenbus_device *dev, > > return 0; > > } > > > > +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 *fedata, > > + uint64_t id, > > + grant_ref_t ref, > > + uint32_t evtchn, > > + struct socket *sock) > > +{ > > + int ret; > > + struct sock_mapping *map; > > + void *page; > > + > > + map = kzalloc(sizeof(*map), GFP_KERNEL); > > + if (map == NULL) > > + return NULL; > > + > > + map->fedata = fedata; > > + map->sock = sock; > > + map->id = id; > > + map->ref = ref; > > + > > + ret = xenbus_map_ring_valloc(fedata->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) { > > + pr_warn("%s frontend requested ring_order %u, which is > MAX (%u)\n", > > + __func__, map->ring_order, MAX_RING_ORDER); > > + goto out; > > + } > > + ret = xenbus_map_ring_valloc(fedata->dev, map->ring->ref, > > + (1 << map->ring_order), &page); > > + if (ret < 0) > > + goto out; > > + map->bytes = page; > > + > > + ret = bind_interdomain_evtchn_to_irqhandler(fedata->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; > > + atomic_set(&map->io, 1); > > + INIT_WORK(&map->ioworker.register_work, pvcalls_back_ioworker); > > + > > + down(&fedata->socket_lock); > > + list_add_tail(&map->list, &fedata->socket_mappings); > > + up(&fedata->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(fedata->dev, fedata, map); > > cleanup? (Unless it is supposed to happen in > pvcalls_back_release_active(), which it is not at this patch level) Yes, pvcalls_back_release_active takes care of the cleanup, it's implemented in patch #13 > > + return NULL; > > +} > > + > > static int pvcalls_back_connect(struct xenbus_device *dev, > > struct xen_pvcalls_request *req) > > { > > + struct pvcalls_fedata *fedata; > > + int ret = -EINVAL; > > + struct socket *sock; > > + struct sock_mapping *map; > > + struct xen_pvcalls_response *rsp; > > + > > + fedata = 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(sock); > > + goto out; > > + } > > + > > + map = pvcalls_new_active_socket(fedata, > > + req->u.connect.id, > > + req->u.connect.ref, > > + req->u.connect.evtchn, > > + sock); > > + if (!map) { > > + sock_release(map->sock); > > + goto out; > > Unnecessary goto. I'll fix > > + } > > + > > +out: > > + rsp = RING_GET_RESPONSE(&fedata->ring, fedata->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; > > Just like in other handlers, return 0? Yes, I'll do that > > +} > > + > > +static int pvcalls_back_release_active(struct xenbus_device *dev, > > + struct pvcalls_fedata *fedata, > > + struct sock_mapping *map) > > +{ > > return 0; > > } > > > > @@ -206,6 +372,11 @@ 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; >