From patchwork Wed Apr 26 05:06:17 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Perevalov X-Patchwork-Id: 9700281 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 B4594603F4 for ; Wed, 26 Apr 2017 05:07:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A4FE3284DB for ; Wed, 26 Apr 2017 05:07:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 96354284EA; Wed, 26 Apr 2017 05:07:50 +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 6C95E2857F for ; Wed, 26 Apr 2017 05:07:49 +0000 (UTC) Received: from localhost ([::1]:52643 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3FB6-0001yY-HY for patchwork-qemu-devel@patchwork.kernel.org; Wed, 26 Apr 2017 01:07:48 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60666) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d3FA2-0001xW-Je for qemu-devel@nongnu.org; Wed, 26 Apr 2017 01:06:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d3F9x-0002uG-QG for qemu-devel@nongnu.org; Wed, 26 Apr 2017 01:06:42 -0400 Received: from mailout4.w1.samsung.com ([210.118.77.14]:12916) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1d3F9x-0002tg-Kb for qemu-devel@nongnu.org; Wed, 26 Apr 2017 01:06:37 -0400 Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout4.w1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0OP00034F3IZ0S00@mailout4.w1.samsung.com> for qemu-devel@nongnu.org; Wed, 26 Apr 2017 06:06:35 +0100 (BST) Received: from eusmges5.samsung.com (unknown [203.254.199.245]) by eucas1p1.samsung.com (KnoxPortal) with ESMTP id 20170426050634eucas1p1055a3607560ce7be1c96806bf985a8af~42jRXp0Uo2460624606eucas1p1g; Wed, 26 Apr 2017 05:06:34 +0000 (GMT) Received: from eucas1p1.samsung.com ( [182.198.249.206]) by eusmges5.samsung.com (EUCPMTA) with SMTP id BB.70.25577.ADA20095; Wed, 26 Apr 2017 06:06:34 +0100 (BST) Received: from eusmgms2.samsung.com (unknown [182.198.249.180]) by eucas1p2.samsung.com (KnoxPortal) with ESMTP id 20170426050633eucas1p2f0c7756e8762fb70d1e1e045095eb3a2~42jQkZVId0153101531eucas1p2g; Wed, 26 Apr 2017 05:06:33 +0000 (GMT) X-AuditID: cbfec7f5-f792f6d0000063e9-52-59002ada818b Received: from eusync1.samsung.com ( [203.254.199.211]) by eusmgms2.samsung.com (EUCPMTA) with SMTP id 51.F7.20206.4FA20095; Wed, 26 Apr 2017 06:07:00 +0100 (BST) Received: from aperevalov-ubuntu.rnd.samsung.ru ([106.109.129.199]) by eusync1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTPA id <0OP000MTF3IPGF20@eusync1.samsung.com>; Wed, 26 Apr 2017 06:06:33 +0100 (BST) From: Alexey Perevalov To: dgilbert@redhat.com Date: Wed, 26 Apr 2017 08:06:17 +0300 Message-id: <1493183181-21962-4-git-send-email-a.perevalov@samsung.com> X-Mailer: git-send-email 1.9.1 In-reply-to: <1493183181-21962-1-git-send-email-a.perevalov@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrPIsWRmVeSWpSXmKPExsWy7djPc7q3tBgiDZa+VrSYe/c8i0Xvtnvs Fic2HWS2uNL+k91iy/5v7BbHe3ewOLB5HHixkN3jybXNTB7v911l8+jbsooxgCWKyyYlNSez LLVI3y6BK6Njw1v2gtsyFY8WxzQwfhftYuTkkBAwkZjYeI0JwhaTuHBvPVsXIxeHkMBSRonL D6YxQTifGSUaVt5kh+l4umM9M0RiGaPEgvWr2CGcbiaJO4tnMXYxcnCwCRhI7LtnC9IgIiAu 8W5fA1gzs0CBxM5PO9hAbGGBeImNp74xgtgsAqoSn/a9AIvzCrhLnDv6mBlimZzEyWOTWUFs TgEPifXr34AtlhB4zCaxpuMPG8guCQFZiU0HoOpdJDrnHoSyhSVeHd8CdbSMxOXJ3SwQve2M Et07O1khnAmMEmem/4Wqspc4dfMqE8SlfBKTtk1nhljAK9HRJgRR4gEMiQ0sELajxL1fm8CW CQnMZpT41KE9gVFmASPDKkaR1NLi3PTUYlO94sTc4tK8dL3k/NxNjMBoPf3v+NcdjEuPWR1i FOBgVOLhDfD4HyHEmlhWXJl7iFGCg1lJhDdcgyFSiDclsbIqtSg/vqg0J7X4EKM0B4uSOC/X qWsRQgLpiSWp2ampBalFMFkmDk6pBsbizR/CWZhLngfOERCbO3/W39J3revaPH11l1juPFS3 uX4D9++LZo4ia2ZoyO802vGtU7xU+0qKyZsfcq9q1Gfv/aYa5blHdgvzAlWnVTP04wJfBf3n E17i9nh3eODOJmXHqhMNzz/Ub+7QYnr14c7RAtkZ6h/9fvnOEPCfzLxN+d+abasu1csosRRn JBpqMRcVJwIAanIlfNICAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrHLMWRmVeSWpSXmKPExsVy+t/xy7pftBgiDRZvFrWYe/c8i0Xvtnvs Fic2HWS2uNL+k91iy/5v7BbHe3ewOLB5HHixkN3jybXNTB7v911l8+jbsooxgCXKzSYjNTEl tUghNS85PyUzL91WKTTETddCSSEvMTfVVilC1zckSEmhLDGnFMgzMkADDs4B7sFK+nYJbhkd G96yF9yWqXi0OKaB8btoFyMnh4SAicTTHeuZIWwxiQv31rN1MXJxCAksYZRofL6XCcLpZZKY fvcRexcjBwebgIHEvnu2IA0iAuIS7/Y1sIPYzAIFEmcX72cEsYUF4iVufXnNBmKzCKhKfNr3 AszmFXCXOHf0MdQyOYmTxyazgticAh4S69e/AYsLAdXMubqMdQIj7wJGhlWMIqmlxbnpucVG esWJucWleel6yfm5mxiBYbvt2M8tOxi73gUfYhTgYFTi4Q3w+B8hxJpYVlyZe4hRgoNZSYQ3 XIMhUog3JbGyKrUoP76oNCe1+BCjKdBRE5mlRJPzgTGVVxJvaGJobmloZGxhYW5kpCTOO/XD lXAhgfTEktTs1NSC1CKYPiYOTqkGxnKb7k3bv/w+YdXz41o+w5bjF8VXvFihYn/L3+/lLreb G9z0tl3MZDzb/V1Ct/eH2nG7gryG6KiHh73a5k9zC7f6tOFG40aPGXHbys+xbP3/kqN7sXi6 lU9f6ZH6w3Ze7+8vcd5SwZbTa1FlqOhvoZz+O7zjjgyPHufbLT9Cru1x3FHgbce4R4mlOCPR UIu5qDgRADWyUiJxAgAA X-MTR: 20000000000000000@CPGS X-CMS-MailID: 20170426050633eucas1p2f0c7756e8762fb70d1e1e045095eb3a2 X-Msg-Generator: CA X-Sender-IP: 182.198.249.180 X-Local-Sender: =?UTF-8?B?QWxleGV5IFBlcmV2YWxvdhtTUlItVmlydHVhbGl6YXRpb24g?= =?UTF-8?B?TGFiG+yCvOyEseyghOyekBtTZW5pb3IgRW5naW5lZXI=?= X-Global-Sender: =?UTF-8?B?QWxleGV5IFBlcmV2YWxvdhtTUlItVmlydHVhbGl6YXRpb24g?= =?UTF-8?B?TGFiG1NhbXN1bmcgRWxlY3Ryb25pY3MbU2VuaW9yIEVuZ2luZWVy?= X-Sender-Code: =?UTF-8?B?QzEwG0NJU0hRG0MxMEdEMDFHRDAxMDE1NA==?= CMS-TYPE: 201P X-HopCount: 7 X-CMS-RootMailID: 20170426050633eucas1p2f0c7756e8762fb70d1e1e045095eb3a2 X-RootMTR: 20170426050633eucas1p2f0c7756e8762fb70d1e1e045095eb3a2 References: <1493183181-21962-1-git-send-email-a.perevalov@samsung.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 210.118.77.14 Subject: [Qemu-devel] [PATCH V3 3/6] migration: split ufd_version_check onto receive/request features part 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: i.maximets@samsung.com, qemu-devel@nongnu.org, a.perevalov@samsung.com, peterx@redhat.com, f4bug@amsat.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP This modification is necessary for userfault fd features which are required to be requested from userspace. UFFD_FEATURE_THREAD_ID is a one of such "on demand" feature, which will be introduced in the next patch. QEMU need to use separate userfault file descriptor, due to userfault context has internal state, and after first call of ioctl UFFD_API it changes its state to UFFD_STATE_RUNNING (in case of success), but kernel while handling ioctl UFFD_API expects UFFD_STATE_WAIT_API. So only one ioctl with UFFD_API is possible per ufd. Signed-off-by: Alexey Perevalov --- migration/postcopy-ram.c | 68 ++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 63 insertions(+), 5 deletions(-) diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index dcf2ed1..55b5243 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -60,15 +60,51 @@ struct PostcopyDiscardState { #include #include -static bool ufd_version_check(int ufd, MigrationIncomingState *mis) + +/* + * Check userfault fd features, to request only supported features in + * future. + * __NR_userfaultfd - should be checked before + * Return obtained features + */ +static bool receive_ufd_features(__u64 *features) { - struct uffdio_api api_struct; - uint64_t ioctl_mask; + struct uffdio_api api_struct = {0}; + int ufd; + bool ret = true; + /* if we are here __NR_userfaultfd should exists */ + ufd = syscall(__NR_userfaultfd, O_CLOEXEC); + if (ufd == -1) { + return false; + } + + /* ask features */ api_struct.api = UFFD_API; api_struct.features = 0; if (ioctl(ufd, UFFDIO_API, &api_struct)) { - error_report("postcopy_ram_supported_by_host: UFFDIO_API failed: %s", + error_report("receive_ufd_features: UFFDIO_API failed: %s", + strerror(errno)); + ret = false; + goto release_ufd; + } + + *features = api_struct.features; + +release_ufd: + close(ufd); + return ret; +} + +static bool request_ufd_features(int ufd, __u64 features) +{ + struct uffdio_api api_struct = {0}; + uint64_t ioctl_mask; + + api_struct.api = UFFD_API; + api_struct.features = features; + if (ioctl(ufd, UFFDIO_API, &api_struct)) { + error_report("request_ufd_features: UFFDIO_API failed: %s", strerror(errno)); return false; } @@ -81,11 +117,33 @@ static bool ufd_version_check(int ufd, MigrationIncomingState *mis) return false; } + return true; +} + +static bool ufd_version_check(int ufd, MigrationIncomingState *mis) +{ + __u64 new_features = 0; + + /* ask features */ + __u64 supported_features; + + if (!receive_ufd_features(&supported_features)) { + error_report("ufd_version_check failed"); + return false; + } + + /* request features */ + if (new_features && !request_ufd_features(ufd, new_features)) { + error_report("ufd_version_check failed: features %" PRIu64, + (uint64_t)new_features); + return false; + } + if (getpagesize() != ram_pagesize_summary()) { bool have_hp = false; /* We've got a huge page */ #ifdef UFFD_FEATURE_MISSING_HUGETLBFS - have_hp = api_struct.features & UFFD_FEATURE_MISSING_HUGETLBFS; + have_hp = supported_features & UFFD_FEATURE_MISSING_HUGETLBFS; #endif if (!have_hp) { error_report("Userfault on this host does not support huge pages");