From patchwork Thu Oct 26 22:59:42 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 10028857 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 A6833601E8 for ; Thu, 26 Oct 2017 23:02:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9712028B69 for ; Thu, 26 Oct 2017 23:02:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8885D28EE4; Thu, 26 Oct 2017 23:02:37 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 110F528B69 for ; Thu, 26 Oct 2017 23:02:36 +0000 (UTC) Received: from localhost ([::1]:54993 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e7rAa-00034e-5C for patchwork-qemu-devel@patchwork.kernel.org; Thu, 26 Oct 2017 19:02:36 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42851) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e7r7t-0001ta-VI for qemu-devel@nongnu.org; Thu, 26 Oct 2017 18:59:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e7r7q-0002Li-TL for qemu-devel@nongnu.org; Thu, 26 Oct 2017 18:59:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:56416) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e7r7q-0002KU-NG for qemu-devel@nongnu.org; Thu, 26 Oct 2017 18:59:46 -0400 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 66FAC21937; Thu, 26 Oct 2017 22:59:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 66FAC21937 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: peter.maydell@linaro.org Date: Thu, 26 Oct 2017 15:59:42 -0700 Message-Id: <1509058783-25851-2-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1509058783-25851-1-git-send-email-sstabellini@kernel.org> References: <1509058783-25851-1-git-send-email-sstabellini@kernel.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 198.145.29.99 Subject: [Qemu-devel] [PULL 2/3] xen: dont try setting max grants multiple times X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , sstabellini@kernel.org, stefanha@gmail.com, qemu-devel@nongnu.org, stefanha@redhat.com, anthony.perard@citrix.com, xen-devel@lists.xenproject.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Juergen Gross Trying to call xengnttab_set_max_grants() with the same file handle might fail on some kernels, as this operation is allowed only once. This is a problem for the qdisk backend as blk_connect() can be called multiple times for a domain, e.g. in case grub-xen is being used to boot it. So instead of letting the generic backend code open the gnttab device do it in blk_connect() and close it again in blk_disconnect. Signed-off-by: Juergen Gross Acked-by: Anthony PERARD Signed-off-by: Stefano Stabellini --- hw/block/xen_disk.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c index 62506e3..e431bd8 100644 --- a/hw/block/xen_disk.c +++ b/hw/block/xen_disk.c @@ -1220,6 +1220,12 @@ static int blk_connect(struct XenDevice *xendev) /* Add on the number needed for the ring pages */ max_grants += blkdev->nr_ring_ref; + blkdev->xendev.gnttabdev = xengnttab_open(NULL, 0); + if (blkdev->xendev.gnttabdev == NULL) { + xen_pv_printf(xendev, 0, "xengnttab_open failed: %s\n", + strerror(errno)); + return -1; + } if (xengnttab_set_max_grants(blkdev->xendev.gnttabdev, max_grants)) { xen_pv_printf(xendev, 0, "xengnttab_set_max_grants failed: %s\n", strerror(errno)); @@ -1327,6 +1333,11 @@ static void blk_disconnect(struct XenDevice *xendev) } blkdev->feature_persistent = false; } + + if (blkdev->xendev.gnttabdev) { + xengnttab_close(blkdev->xendev.gnttabdev); + blkdev->xendev.gnttabdev = NULL; + } } static int blk_free(struct XenDevice *xendev) @@ -1334,9 +1345,7 @@ static int blk_free(struct XenDevice *xendev) struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); struct ioreq *ioreq; - if (blkdev->blk || blkdev->sring) { - blk_disconnect(xendev); - } + blk_disconnect(xendev); while (!QLIST_EMPTY(&blkdev->freelist)) { ioreq = QLIST_FIRST(&blkdev->freelist); @@ -1363,7 +1372,6 @@ static void blk_event(struct XenDevice *xendev) struct XenDevOps xen_blkdev_ops = { .size = sizeof(struct XenBlkDev), - .flags = DEVOPS_FLAG_NEED_GNTDEV, .alloc = blk_alloc, .init = blk_init, .initialise = blk_connect,