From patchwork Fri Sep 15 23:00:32 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 9953963 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 CA926601AE for ; Fri, 15 Sep 2017 23:03:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B53CA29588 for ; Fri, 15 Sep 2017 23:03:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A9DC82958D; Fri, 15 Sep 2017 23:03:41 +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 06D6329588 for ; Fri, 15 Sep 2017 23:03:41 +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 1dszbN-0004Us-Ll; Fri, 15 Sep 2017 23:00:49 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dszbL-0004T2-Ub for xen-devel@lists.xen.org; Fri, 15 Sep 2017 23:00:48 +0000 Received: from [85.158.137.68] by server-7.bemta-3.messagelabs.com id A6/F4-02224-F9B5CB95; Fri, 15 Sep 2017 23:00:47 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmpgkeJIrShJLcpLzFFi42I5NlE2WXde9J5 IgxvPFS2WfFzM4sDocXT3b6YAxijWzLyk/IoE1oy5iy6wFXwyqNjTM4m5gfGtZhcjF4eQwDom iR3nHrF1MXJysAg4SEx6uJmpi5GDg1EgRuLBD2uQMKNAmMTky0tYQWw2AUOJv082gZWLCEhLX Pt8mRFkDrPAZEaJ1+9+MYP0CgPN2dkWBTFSVaL51lVGEJtXwE1iypSDTCC2hICcxMljk8Fmcg q4Szzff4kF4p42RolnezewT2DkXcDIsIpRozi1qCy1SNfIUC+pKDM9oyQ3MTNH19DAWC83tbg 4MT01JzGpWC85P3cTIzAc6hkYGHcw9uz1O8QoycGkJMpr5bcnUogvKT+lMiOxOCO+qDQntfgQ owwHh5IEb2MUUE6wKDU9tSItMwcYmDBpCQ4eJRHeQJA0b3FBYm5xZjpE6hSjMcexTZf/MHF03 Lz7h0mIJS8/L1VKnNcfpFQApDSjNA9uECxiLjHKSgnzMjIwMAjxFKQW5WaWoMq/YhTnYFQShp jCk5lXArfvFdApTECnnDm9A+SUkkSElFQDY8yV/WZTTd5OePywOL5+63fx+OT9Kg8dOuUumN2 sePt69cKcWb8+hmdMCl/4erPRpce6W/1r3syUCLV9mb3I2rG7t4h98emukxF8jYoHD17VbVYL fO5uvfPC9CR3mYxvnqU5CxQOOZXdNpyyaNejk1HO8Vy3L+2a/XJZxWaV+W8XC9ZH3uLf2K3EU pyRaKjFXFScCAC9DySBkwIAAA== X-Env-Sender: sstabellini@kernel.org X-Msg-Ref: server-3.tower-31.messagelabs.com!1505516445!115055142!1 X-Originating-IP: [198.145.29.99] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.4.45; banners=-,-,- X-VirusChecked: Checked Received: (qmail 34395 invoked from network); 15 Sep 2017 23:00:46 -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; 15 Sep 2017 23:00:46 -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 3D21422A79; Fri, 15 Sep 2017 23:00:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3D21422A79 From: Stefano Stabellini To: xen-devel@lists.xen.org Date: Fri, 15 Sep 2017 16:00:32 -0700 Message-Id: <1505516440-11111-5-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1505516440-11111-1-git-send-email-sstabellini@kernel.org> References: <1505516440-11111-1-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 v4 05/13] xen/pvcalls: implement connect 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_CONNECT to the backend. Allocate a new ring and evtchn for the active socket. Introduce fields in struct sock_mapping to keep track of active sockets. Introduce a waitqueue to allow the frontend to wait on data coming from the backend on the active socket (recvmsg command). Two mutexes (one of reads and one for writes) will be used to protect the active socket in and out rings from concurrent accesses. Signed-off-by: Stefano Stabellini CC: boris.ostrovsky@oracle.com CC: jgross@suse.com Reviewed-by: Boris Ostrovsky --- drivers/xen/pvcalls-front.c | 163 ++++++++++++++++++++++++++++++++++++++++++++ drivers/xen/pvcalls-front.h | 2 + 2 files changed, 165 insertions(+) diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index 1bad1b1..ef511b6 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -13,6 +13,10 @@ */ #include +#include +#include + +#include #include #include @@ -57,6 +61,18 @@ struct sock_mapping { bool active_socket; struct list_head list; struct socket *sock; + union { + struct { + int irq; + grant_ref_t ref; + struct pvcalls_data_intf *ring; + struct pvcalls_data data; + struct mutex in_mutex; + struct mutex out_mutex; + + wait_queue_head_t inflight_conn_req; + } active; + }; }; static inline int get_request(struct pvcalls_bedata *bedata, int *req_id) @@ -114,6 +130,18 @@ static irqreturn_t pvcalls_front_event_handler(int irq, void *dev_id) return IRQ_HANDLED; } +static irqreturn_t pvcalls_front_conn_handler(int irq, void *sock_map) +{ + struct sock_mapping *map = sock_map; + + if (map == NULL) + return IRQ_HANDLED; + + wake_up_interruptible(&map->active.inflight_conn_req); + + return IRQ_HANDLED; +} + int pvcalls_front_socket(struct socket *sock) { struct pvcalls_bedata *bedata; @@ -191,6 +219,133 @@ int pvcalls_front_socket(struct socket *sock) return ret; } +static int create_active(struct sock_mapping *map, int *evtchn) +{ + void *bytes; + int ret = -ENOMEM, irq = -1, i; + + *evtchn = -1; + init_waitqueue_head(&map->active.inflight_conn_req); + + map->active.ring = (struct pvcalls_data_intf *) + __get_free_page(GFP_KERNEL | __GFP_ZERO); + if (map->active.ring == NULL) + goto out_error; + map->active.ring->ring_order = PVCALLS_RING_ORDER; + bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + PVCALLS_RING_ORDER); + if (bytes == NULL) + goto out_error; + for (i = 0; i < (1 << PVCALLS_RING_ORDER); i++) + map->active.ring->ref[i] = gnttab_grant_foreign_access( + pvcalls_front_dev->otherend_id, + pfn_to_gfn(virt_to_pfn(bytes) + i), 0); + + map->active.ref = gnttab_grant_foreign_access( + pvcalls_front_dev->otherend_id, + pfn_to_gfn(virt_to_pfn((void *)map->active.ring)), 0); + + map->active.data.in = bytes; + map->active.data.out = bytes + + XEN_FLEX_RING_SIZE(PVCALLS_RING_ORDER); + + ret = xenbus_alloc_evtchn(pvcalls_front_dev, evtchn); + if (ret) + goto out_error; + irq = bind_evtchn_to_irqhandler(*evtchn, pvcalls_front_conn_handler, + 0, "pvcalls-frontend", map); + if (irq < 0) { + ret = irq; + goto out_error; + } + + map->active.irq = irq; + map->active_socket = true; + mutex_init(&map->active.in_mutex); + mutex_init(&map->active.out_mutex); + + return 0; + +out_error: + if (irq >= 0) + unbind_from_irqhandler(irq, map); + else if (*evtchn >= 0) + xenbus_free_evtchn(pvcalls_front_dev, *evtchn); + kfree(map->active.data.in); + kfree(map->active.ring); + return ret; +} + +int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr, + int addr_len, int flags) +{ + struct pvcalls_bedata *bedata; + struct sock_mapping *map = NULL; + struct xen_pvcalls_request *req; + int notify, req_id, ret, evtchn; + + pvcalls_enter; + if (!pvcalls_front_dev) { + pvcalls_exit; + return -ENETUNREACH; + } + if (addr->sa_family != AF_INET || sock->type != SOCK_STREAM) { + pvcalls_exit; + return -ENOTSUPP; + } + + bedata = dev_get_drvdata(&pvcalls_front_dev->dev); + + map = (struct sock_mapping *) sock->sk->sk_send_head; + if (!map) { + pvcalls_exit; + return -ENOTSOCK; + } + + spin_lock(&bedata->socket_lock); + ret = get_request(bedata, &req_id); + if (ret < 0) { + spin_unlock(&bedata->socket_lock); + pvcalls_exit; + return ret; + } + ret = create_active(map, &evtchn); + if (ret < 0) { + spin_unlock(&bedata->socket_lock); + pvcalls_exit; + return ret; + } + + req = RING_GET_REQUEST(&bedata->ring, req_id); + req->req_id = req_id; + req->cmd = PVCALLS_CONNECT; + req->u.connect.id = (uint64_t)map; + memcpy(req->u.connect.addr, addr, sizeof(*addr)); + req->u.connect.len = addr_len; + req->u.connect.flags = flags; + req->u.connect.ref = map->active.ref; + req->u.connect.evtchn = evtchn; + + map->sock = sock; + + bedata->ring.req_prod_pvt++; + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&bedata->ring, notify); + spin_unlock(&bedata->socket_lock); + + if (notify) + notify_remote_via_irq(bedata->irq); + + wait_event(bedata->inflight_req, + READ_ONCE(bedata->rsp[req_id].req_id) == req_id); + + 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); + pvcalls_exit; + return ret; +} + static const struct xenbus_device_id pvcalls_front_ids[] = { { "pvcalls" }, { "" } @@ -207,6 +362,14 @@ static int pvcalls_front_remove(struct xenbus_device *dev) if (bedata->irq >= 0) unbind_from_irqhandler(bedata->irq, dev); + list_for_each_entry_safe(map, n, &bedata->socket_mappings, list) { + map->sock->sk->sk_send_head = NULL; + if (map->active_socket) { + map->active.ring->in_error = -EBADF; + wake_up_interruptible(&map->active.inflight_conn_req); + } + } + smp_mb(); while (atomic_read(&pvcalls_refcount) > 0) cpu_relax(); diff --git a/drivers/xen/pvcalls-front.h b/drivers/xen/pvcalls-front.h index b7dabed..63b0417 100644 --- a/drivers/xen/pvcalls-front.h +++ b/drivers/xen/pvcalls-front.h @@ -4,5 +4,7 @@ #include int pvcalls_front_socket(struct socket *sock); +int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr, + int addr_len, int flags); #endif