From patchwork Tue Jul 25 21:22:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 9863845 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 383FE6038C for ; Tue, 25 Jul 2017 21:25:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 201D428405 for ; Tue, 25 Jul 2017 21:25:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 12F0F2870E; Tue, 25 Jul 2017 21:25:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6EC2A28405 for ; Tue, 25 Jul 2017 21:25:01 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1da7I5-00052Z-8o; Tue, 25 Jul 2017 21:22:53 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1da7I3-00050Y-RY for xen-devel@lists.xen.org; Tue, 25 Jul 2017 21:22:51 +0000 Received: from [85.158.137.68] by server-14.bemta-3.messagelabs.com id 37/13-01862-BA6B7795; Tue, 25 Jul 2017 21:22:51 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpgkeJIrShJLcpLzFFi42I5NlE2WXfVtvJ Ig2+npS2WfFzM4sDocXT3b6YAxijWzLyk/IoE1owL1y8yFxyVq5h5dyJjA+NmqS5GLg4hgXVM Ems3HmHuYuTkYBFwkFjU3sfYxcjBwSgQI/HghzVImFEgTGLy5SWsIDabgKHE3yeb2EBsEQFpi WufLzOCzGEWmMwo8frdL2aQXmEBe4n7ky0gRqpKbDn/DayeV8BNYun3I2BzJATkJE4emwxmcw q4S8yfuZ0F4p52RomPW08zT2DkXcDIsIpRozi1qCy1SNfQSC+pKDM9oyQ3MTNH19DAWC83tbg 4MT01JzGpWC85P3cTIzAcGIBgB+OrbudDjJIcTEqivN90yyOF+JLyUyozEosz4otKc1KLDzHK cHAoSfBO2gqUEyxKTU+tSMvMAQYmTFqCg0dJhLcXJM1bXJCYW5yZDpE6xWjMsWH1+i9MHK8m/ P/GJMSSl5+XKiXOawBSKgBSmlGaBzcIFjGXGGWlhHkZgU4T4ilILcrNLEGVf8UozsGoJMyrAD KFJzOvBG7fK6BTmIBOmTOjFOSUkkSElFQDYyGTTf6LCdyHDp+zkV1YkGt/6mfpSqXfAczthjp v5tnaluVpz58j0u1jXGM2V/fO+rdJSyU26P/oY/7qKr0xXjBSWZ7T9tf37/uXcaqvE/xydoZw xZHuE6el0y/JHclbY6J38NfX1g+fQl59nWr1NT5X9FTvwVd8O+9sTTpsG/x42YV+VcPND5RYi jMSDbWYi4oTAaIQXvyTAgAA X-Env-Sender: sstabellini@kernel.org X-Msg-Ref: server-3.tower-31.messagelabs.com!1501017769!107092988!1 X-Originating-IP: [198.145.29.99] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.4.25; banners=-,-,- X-VirusChecked: Checked Received: (qmail 62415 invoked from network); 25 Jul 2017 21:22:50 -0000 Received: from mail.kernel.org (HELO mail.kernel.org) (198.145.29.99) by server-3.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 25 Jul 2017 21:22:50 -0000 Received: from localhost.localdomain (162-198-228-33.lightspeed.wlfrct.sbcglobal.net [162.198.228.33]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6FB6E22CAE; Tue, 25 Jul 2017 21:22:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6FB6E22CAE From: Stefano Stabellini To: xen-devel@lists.xen.org Date: Tue, 25 Jul 2017 14:22:04 -0700 Message-Id: <1501017730-12797-7-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1501017730-12797-1-git-send-email-sstabellini@kernel.org> References: <1501017730-12797-1-git-send-email-sstabellini@kernel.org> Cc: jgross@suse.com, Stefano Stabellini , boris.ostrovsky@oracle.com, sstabellini@kernel.org, linux-kernel@vger.kernel.org Subject: [Xen-devel] [PATCH v2 07/13] xen/pvcalls: implement accept command X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP Send PVCALLS_ACCEPT to the backend. Allocate a new active socket. Make sure that only one accept command is executed at any given time by setting PVCALLS_FLAG_ACCEPT_INFLIGHT and waiting on the inflight_accept_req waitqueue. sock->sk->sk_send_head is not used for ip sockets: reuse the field to store a pointer to the struct sock_mapping corresponding to the socket. Convert the new struct socket pointer into an uint64_t and use it as id for the new socket to pass to the backend. Signed-off-by: Stefano Stabellini CC: boris.ostrovsky@oracle.com CC: jgross@suse.com --- drivers/xen/pvcalls-front.c | 79 +++++++++++++++++++++++++++++++++++++++++++++ drivers/xen/pvcalls-front.h | 3 ++ 2 files changed, 82 insertions(+) diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index 3b5d50e..b8c4538 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -413,6 +413,85 @@ int pvcalls_front_listen(struct socket *sock, int backlog) return ret; } +int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags) +{ + struct pvcalls_bedata *bedata; + struct sock_mapping *map; + struct sock_mapping *map2 = NULL; + struct xen_pvcalls_request *req; + int notify, req_id, ret, evtchn; + + 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_LISTEN) + return -EINVAL; + + /* + * Backend only supports 1 inflight accept request, will return + * errors for the others + */ + if (test_and_set_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, + (void *)&map->passive.flags)) { + if (wait_event_interruptible(map->passive.inflight_accept_req, + !test_and_set_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, + (void *)&map->passive.flags)) + != 0) + return -EINTR; + } + + + newsock->sk = kzalloc(sizeof(*newsock->sk), GFP_KERNEL); + if (newsock->sk == NULL) + return -ENOMEM; + + spin_lock(&bedata->pvcallss_lock); + req_id = bedata->ring.req_prod_pvt & (RING_SIZE(&bedata->ring) - 1); + if (RING_FULL(&bedata->ring) || + READ_ONCE(bedata->rsp[req_id].req_id) != PVCALLS_INVALID_ID) { + kfree(newsock->sk); + spin_unlock(&bedata->pvcallss_lock); + return -EAGAIN; + } + + map2 = create_active(&evtchn); + + req = RING_GET_REQUEST(&bedata->ring, req_id); + req->req_id = req_id; + req->cmd = PVCALLS_ACCEPT; + req->u.accept.id = (uint64_t) sock; + req->u.accept.ref = map2->active.ref; + req->u.accept.id_new = (uint64_t) newsock; + req->u.accept.evtchn = evtchn; + + list_add_tail(&map2->list, &bedata->socket_mappings); + WRITE_ONCE(newsock->sk->sk_send_head, (void *)map2); + map2->sock = newsock; + + 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); + + clear_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, (void *)&map->passive.flags); + wake_up(&map->passive.inflight_accept_req); + + 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 aa8fe10..ab4f1da 100644 --- a/drivers/xen/pvcalls-front.h +++ b/drivers/xen/pvcalls-front.h @@ -10,5 +10,8 @@ int pvcalls_front_bind(struct socket *sock, struct sockaddr *addr, int addr_len); int pvcalls_front_listen(struct socket *sock, int backlog); +int pvcalls_front_accept(struct socket *sock, + struct socket *newsock, + int flags); #endif