From patchwork Mon Nov 28 19:42:23 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 9450135 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 DF25B60235 for ; Mon, 28 Nov 2016 19:44:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CDDEB27F9C for ; Mon, 28 Nov 2016 19:44:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C286B27FAD; Mon, 28 Nov 2016 19:44:53 +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 41AEF27F9C for ; Mon, 28 Nov 2016 19:44:53 +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 1cBRow-0000UF-B4; Mon, 28 Nov 2016 19:42:34 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cBRov-0000U3-8R for xen-devel@lists.xenproject.org; Mon, 28 Nov 2016 19:42:33 +0000 Received: from [85.158.139.211] by server-1.bemta-5.messagelabs.com id 41/27-16850-8A88C385; Mon, 28 Nov 2016 19:42:32 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrJLMWRWlGSWpSXmKPExsVybKJsh+7yDps Ig3n3LSy+b5nM5MDocfjDFZYAxijWzLyk/IoE1oz//+YwFSwSr7iwKaWBsU2oi5GTQ0hgKqNE 7wnRLkYuIHs7k8SNY92sIAk2AUOJv082sYHYIgJiEqd3T2MCKWIW2M8osbm9AywhLBAksfPbA iYQm0VAVWLXmn1gzbwCbhJXPn0AsyUE5CROHpsMZHNwcAr4SLw8Fw+x2Fti7tN3TBAlGRLzeu ZAlXtJLLpxCcpWk7h6bhPzBEa+BYwMqxg1ilOLylKLdI0M9JKKMtMzSnITM3N0DQ1M9XJTi4s T01NzEpOK9ZLzczcxAoOknoGBcQdj42y/Q4ySHExKorzT3WwihPiS8lMqMxKLM+KLSnNSiw8x ynBwKEnwtrYD5QSLUtNTK9Iyc4DhCpOW4OBREuF92wqU5i0uSMwtzkyHSJ1iVJQS500F6RMAS WSU5sG1wWLkEqOslDAvIwMDgxBPQWpRbmYJqvwrRnEORiVh3nkgU3gy80rgpr8CWswEsvi1Nc jikkSElFQDoyZHvM4q63Ddf343TfMnPNTWm3W8JPRi0duzWX+DW47+7tWKjWn56bjM4fweAY2 3LTdLe82K30tc/qeyJrfh2MX+A8qnN+wxeByw/NfktSd5yrtfmCY3yGTejDoTNT/z3s0rGTo+ zy6YGOY+n7qAx//s9ObrSsynrHYubPl/7+CVRa9NXj87NVWJpTgj0VCLuag4EQA/XJ7SjAIAA A== X-Env-Sender: sstabellini@kernel.org X-Msg-Ref: server-7.tower-206.messagelabs.com!1480362146!72502649!1 X-Originating-IP: [198.145.29.136] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.0.16; banners=-,-,- X-VirusChecked: Checked Received: (qmail 3988 invoked from network); 28 Nov 2016 19:42:27 -0000 Received: from mail.kernel.org (HELO mail.kernel.org) (198.145.29.136) by server-7.tower-206.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 28 Nov 2016 19:42:27 -0000 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1C2DD20172; Mon, 28 Nov 2016 19:42:29 +0000 (UTC) Received: from sstabellini-ThinkPad-X260.hsd1.ca.comcast.net (96-82-76-110-static.hfc.comcastbusiness.net [96.82.76.110]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AB9982013D; Mon, 28 Nov 2016 19:42:27 +0000 (UTC) From: Stefano Stabellini To: stefanha@gmail.com Date: Mon, 28 Nov 2016 11:42:23 -0800 Message-Id: <1480362146-14873-1-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: X-Virus-Scanned: ClamAV using ClamSMTP Cc: peter.maydell@linaro.org, Olaf Hering , sstabellini@kernel.org, qemu-devel@nongnu.org, stefanha@redhat.com, anthony.perard@citrix.com, xen-devel@lists.xenproject.org Subject: [Xen-devel] [PULL 1/4] xen_disk: split discard input to match internal representation 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 From: Olaf Hering The guest sends discard requests as u64 sector/count pairs, but the block layer operates internally with s64/s32 pairs. The conversion leads to IO errors in the guest, the discard request is not processed. domU.cfg: 'vdev=xvda, format=qcow2, backendtype=qdisk, target=/x.qcow2' domU: mkfs.ext4 -F /dev/xvda Discarding device blocks: failed - Input/output error Fix this by splitting the request into chunks of BDRV_REQUEST_MAX_SECTORS. Add input range checking to avoid overflow. Fixes f313520 ("xen_disk: add discard support") Signed-off-by: Olaf Hering Reviewed-by: Eric Blake Reviewed-by: Stefano Stabellini --- hw/block/xen_disk.c | 42 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 36 insertions(+), 6 deletions(-) diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c index 3a7dc19..456a2d5 100644 --- a/hw/block/xen_disk.c +++ b/hw/block/xen_disk.c @@ -660,6 +660,38 @@ static void qemu_aio_complete(void *opaque, int ret) qemu_bh_schedule(ioreq->blkdev->bh); } +static bool blk_split_discard(struct ioreq *ioreq, blkif_sector_t sector_number, + uint64_t nr_sectors) +{ + struct XenBlkDev *blkdev = ioreq->blkdev; + int64_t byte_offset; + int byte_chunk; + uint64_t byte_remaining, limit; + uint64_t sec_start = sector_number; + uint64_t sec_count = nr_sectors; + + /* Wrap around, or overflowing byte limit? */ + if (sec_start + sec_count < sec_count || + sec_start + sec_count > INT64_MAX >> BDRV_SECTOR_BITS) { + return false; + } + + limit = BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS; + byte_offset = sec_start << BDRV_SECTOR_BITS; + byte_remaining = sec_count << BDRV_SECTOR_BITS; + + do { + byte_chunk = byte_remaining > limit ? limit : byte_remaining; + ioreq->aio_inflight++; + blk_aio_pdiscard(blkdev->blk, byte_offset, byte_chunk, + qemu_aio_complete, ioreq); + byte_remaining -= byte_chunk; + byte_offset += byte_chunk; + } while (byte_remaining > 0); + + return true; +} + static int ioreq_runio_qemu_aio(struct ioreq *ioreq) { struct XenBlkDev *blkdev = ioreq->blkdev; @@ -708,12 +740,10 @@ static int ioreq_runio_qemu_aio(struct ioreq *ioreq) break; case BLKIF_OP_DISCARD: { - struct blkif_request_discard *discard_req = (void *)&ioreq->req; - ioreq->aio_inflight++; - blk_aio_pdiscard(blkdev->blk, - discard_req->sector_number << BDRV_SECTOR_BITS, - discard_req->nr_sectors << BDRV_SECTOR_BITS, - qemu_aio_complete, ioreq); + struct blkif_request_discard *req = (void *)&ioreq->req; + if (!blk_split_discard(ioreq, req->sector_number, req->nr_sectors)) { + goto err; + } break; } default: