From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752833AbdGEVvU (ORCPT ); Wed, 5 Jul 2017 17:51:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:60204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752658AbdGEVvS (ORCPT ); Wed, 5 Jul 2017 17:51:18 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A8C3A22BD4 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 From: Stefano Stabellini To: xen-devel@lists.xen.org Cc: linux-kernel@vger.kernel.org, sstabellini@kernel.org, jgross@suse.com, boris.ostrovsky@oracle.com, Stefano Stabellini Subject: [PATCH v7 17/18] xen/pvcalls: implement write Date: Wed, 5 Jul 2017 14:50:57 -0700 Message-Id: <1499291458-30231-17-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1499291458-30231-1-git-send-email-sstabellini@kernel.org> References: <1499291458-30231-1-git-send-email-sstabellini@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When the other end notifies us that there is data to be written (pvcalls_back_conn_event), increment the io and write counters, and schedule the ioworker. Implement the write function called by ioworker by reading the data from the data ring, writing it to the socket by calling inet_sendmsg. Set out_error on error. Signed-off-by: Stefano Stabellini Reviewed-by: Juergen Gross CC: boris.ostrovsky@oracle.com CC: jgross@suse.com --- drivers/xen/pvcalls-back.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index 970db9d..d6c4c4a 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -177,6 +177,64 @@ static void pvcalls_conn_back_read(void *opaque) static void pvcalls_conn_back_write(struct sock_mapping *map) { + struct pvcalls_data_intf *intf = map->ring; + struct pvcalls_data *data = &map->data; + struct msghdr msg; + struct kvec vec[2]; + RING_IDX cons, prod, size, array_size; + int ret; + + cons = intf->out_cons; + prod = intf->out_prod; + /* read the indexes before dealing with the data */ + virt_mb(); + + array_size = XEN_FLEX_RING_SIZE(map->ring_order); + size = pvcalls_queued(prod, cons, array_size); + if (size == 0) + return; + + memset(&msg, 0, sizeof(msg)); + msg.msg_flags |= MSG_DONTWAIT; + msg.msg_iter.type = ITER_KVEC|READ; + msg.msg_iter.count = size; + if (pvcalls_mask(prod, array_size) > pvcalls_mask(cons, array_size)) { + vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); + vec[0].iov_len = size; + msg.msg_iter.kvec = vec; + msg.msg_iter.nr_segs = 1; + } else { + vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); + vec[0].iov_len = array_size - pvcalls_mask(cons, array_size); + vec[1].iov_base = data->out; + vec[1].iov_len = size - vec[0].iov_len; + msg.msg_iter.kvec = vec; + msg.msg_iter.nr_segs = 2; + } + + atomic_set(&map->write, 0); + ret = inet_sendmsg(map->sock, &msg, size); + if (ret == -EAGAIN || (ret >= 0 && ret < size)) { + atomic_inc(&map->write); + atomic_inc(&map->io); + } + if (ret == -EAGAIN) + return; + + /* write the data, then update the indexes */ + virt_wmb(); + if (ret < 0) { + intf->out_error = ret; + } else { + intf->out_error = 0; + intf->out_cons = cons + ret; + prod = intf->out_prod; + } + /* update the indexes, then notify the other end */ + virt_wmb(); + if (prod != cons + ret) + atomic_inc(&map->write); + notify_remote_via_irq(map->irq); } static void pvcalls_back_ioworker(struct work_struct *work) @@ -845,6 +903,19 @@ static irqreturn_t pvcalls_back_event(int irq, void *dev_id) static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map) { + struct sock_mapping *map = sock_map; + struct pvcalls_ioworker *iow; + + if (map == NULL || map->sock == NULL || map->sock->sk == NULL || + map->sock->sk->sk_user_data != map) + return IRQ_HANDLED; + + iow = &map->ioworker; + + atomic_inc(&map->write); + atomic_inc(&map->io); + queue_work(iow->wq, &iow->register_work); + return IRQ_HANDLED; } -- 1.9.1