From patchwork Fri Sep 15 23:00:39 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 9953945 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 CB9E6601AE for ; Fri, 15 Sep 2017 23:03:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B6DC229588 for ; Fri, 15 Sep 2017 23:03:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AA5802958E; Fri, 15 Sep 2017 23:03:21 +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 3CC9D29588 for ; Fri, 15 Sep 2017 23:03:21 +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 1dszbP-0004XN-8x; Fri, 15 Sep 2017 23:00:51 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dszbN-0004UJ-Jt for xen-devel@lists.xen.org; Fri, 15 Sep 2017 23:00:49 +0000 Received: from [85.158.137.68] by server-4.bemta-3.messagelabs.com id 4A/34-02229-0AB5CB95; Fri, 15 Sep 2017 23:00:48 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrPLMWRWlGSWpSXmKPExsVybKJssu6C6D2 RBp++CVss+biYxYHR4+ju30wBjFGsmXlJ+RUJrBkXTzkUvFeoOD1xH3sDY5dMFyMXh5DAOiaJ 6zfusXUxcnKwCDhI3L83m6WLkYODUSBG4sEPa5Awo0CYxOTLS1hBbDYBQ4m/TzaBlYsISEtc+ 3yZEWQOs8BkRonX734xgySEgeZsfz2NEWKmqsTHl1/BGngF3CUmz70DViMhICdx8thksKGcQP Hn+y+xQBzUxijxbO8G9gmMvAsYGVYxqhenFpWlFuma6yUVZaZnlOQmZuboGhoY6+WmFhcnpqf mJCYV6yXn525iBAYDAxDsYGz87nSIUZKDSUmU18pvT6QQX1J+SmVGYnFGfFFpTmrxIUYZDg4l Cd7VUUA5waLU9NSKtMwcYFjCpCU4eJREeANB0rzFBYm5xZnpEKlTjMYcxzZd/sPE0XHz7h8mI Za8/LxUKXFef5BSAZDSjNI8uEGweLnEKCslzMsIdJoQT0FqUW5mCar8K0ZxDkYlYd4TIFN4Mv NK4Pa9AjqFCeiUM6d3gJxSkoiQkmpgNJvRE2hwbSLf76Uctqn7fddE32OTOKpcd2bK4ukC567 ybnqlPj98zsomuZYbPJ9z39V6cOzWXv1/iVTerP156+SK9+2o9uxUik2v3GpqavL28cy1dU/O yYRWNz/9tCGNdZtPqEXbLZENFUYCqpeOnjY90Wf2Kf5nfOPtKxc8Kja0xgfueGT0SYmlOCPRU Iu5qDgRAGOWEWOSAgAA X-Env-Sender: sstabellini@kernel.org X-Msg-Ref: server-12.tower-31.messagelabs.com!1505516447!98246974!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 64602 invoked from network); 15 Sep 2017 23:00:48 -0000 Received: from mail.kernel.org (HELO mail.kernel.org) (198.145.29.99) by server-12.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 15 Sep 2017 23:00:48 -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 80C8D22A78; Fri, 15 Sep 2017 23:00:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 80C8D22A78 From: Stefano Stabellini To: xen-devel@lists.xen.org Date: Fri, 15 Sep 2017 16:00:39 -0700 Message-Id: <1505516440-11111-12-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 12/13] xen/pvcalls: implement release 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_RELEASE to the backend and wait for a reply. Take both in_mutex and out_mutex to avoid concurrent accesses. Then, free the socket. For passive sockets, check whether we have already pre-allocated an active socket for the purpose of being accepted. If so, free that as well. Signed-off-by: Stefano Stabellini CC: boris.ostrovsky@oracle.com CC: jgross@suse.com --- drivers/xen/pvcalls-front.c | 104 ++++++++++++++++++++++++++++++++++++++++++++ drivers/xen/pvcalls-front.h | 1 + 2 files changed, 105 insertions(+) diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index 8a90213..5f8e94a 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -209,6 +209,24 @@ static irqreturn_t pvcalls_front_conn_handler(int irq, void *sock_map) return IRQ_HANDLED; } +static void pvcalls_front_free_map(struct pvcalls_bedata *bedata, + struct sock_mapping *map) +{ + int i; + + unbind_from_irqhandler(map->active.irq, map); + + spin_lock(&bedata->socket_lock); + if (!list_empty(&map->list)) + list_del_init(&map->list); + spin_unlock(&bedata->socket_lock); + + for (i = 0; i < (1 << PVCALLS_RING_ORDER); i++) + gnttab_end_foreign_access(map->active.ring->ref[i], 0, 0); + gnttab_end_foreign_access(map->active.ref, 0, 0); + free_page((unsigned long)map->active.ring); +} + int pvcalls_front_socket(struct socket *sock) { struct pvcalls_bedata *bedata; @@ -960,6 +978,92 @@ unsigned int pvcalls_front_poll(struct file *file, struct socket *sock, return ret; } +int pvcalls_front_release(struct socket *sock) +{ + struct pvcalls_bedata *bedata; + struct sock_mapping *map; + int req_id, notify, ret; + struct xen_pvcalls_request *req; + + pvcalls_enter; + if (!pvcalls_front_dev) { + pvcalls_exit; + return -EIO; + } + if (sock->sk == NULL) { + pvcalls_exit; + return 0; + } + + bedata = dev_get_drvdata(&pvcalls_front_dev->dev); + + map = (struct sock_mapping *) sock->sk->sk_send_head; + if (map == NULL) { + pvcalls_exit; + return 0; + } + + spin_lock(&bedata->socket_lock); + ret = get_request(bedata, &req_id); + if (ret < 0) { + spin_unlock(&bedata->socket_lock); + pvcalls_exit; + return ret; + } + sock->sk->sk_send_head = NULL; + + req = RING_GET_REQUEST(&bedata->ring, req_id); + req->req_id = req_id; + req->cmd = PVCALLS_RELEASE; + req->u.release.id = (uint64_t)map; + + 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); + + if (map->active_socket) { + /* + * Set in_error and wake up inflight_conn_req to force + * recvmsg waiters to exit. + */ + map->active.ring->in_error = -EBADF; + wake_up_interruptible(&map->active.inflight_conn_req); + + /* + * Wait until there are no more waiters on the mutexes. + * We know that no new waiters can be added because sk_send_head + * is set to NULL -- we only need to wait for the existing + * waiters to return. + */ + while (!mutex_trylock(&map->active.in_mutex) || + !mutex_trylock(&map->active.out_mutex)) + cpu_relax(); + + pvcalls_front_free_map(bedata, map); + kfree(map); + } else { + spin_lock(&bedata->socket_lock); + if (READ_ONCE(map->passive.inflight_req_id) != + PVCALLS_INVALID_ID) { + pvcalls_front_free_map(bedata, + map->passive.accept_map); + kfree(map->passive.accept_map); + } + list_del_init(&map->list); + kfree(map); + spin_unlock(&bedata->socket_lock); + } + WRITE_ONCE(bedata->rsp[req_id].req_id, PVCALLS_INVALID_ID); + + pvcalls_exit; + return 0; +} + 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 25e05b8..3332978 100644 --- a/drivers/xen/pvcalls-front.h +++ b/drivers/xen/pvcalls-front.h @@ -23,5 +23,6 @@ int pvcalls_front_recvmsg(struct socket *sock, unsigned int pvcalls_front_poll(struct file *file, struct socket *sock, poll_table *wait); +int pvcalls_front_release(struct socket *sock); #endif