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GET /api/patches/806817/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 806817,
    "url": "http://patchwork.ozlabs.org/api/patches/806817/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/patch/1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com/",
    "project": {
        "id": 14,
        "url": "http://patchwork.ozlabs.org/api/projects/14/?format=api",
        "name": "QEMU Development",
        "link_name": "qemu-devel",
        "list_id": "qemu-devel.nongnu.org",
        "list_email": "qemu-devel@nongnu.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": "",
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com>",
    "list_archive_url": null,
    "date": "2017-08-29T00:13:54",
    "name": "[19/79] block: Reuse bs as backing hd for drive-backup sync=none",
    "commit_ref": null,
    "pull_url": null,
    "state": "new",
    "archived": false,
    "hash": "af2955725b2f3bf0dc2e3ca0501ceb9d305d3b3d",
    "submitter": {
        "id": 5549,
        "url": "http://patchwork.ozlabs.org/api/people/5549/?format=api",
        "name": "Michael Roth",
        "email": "mdroth@linux.vnet.ibm.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/qemu-devel/patch/1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com/mbox/",
    "series": [
        {
            "id": 281,
            "url": "http://patchwork.ozlabs.org/api/series/281/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/list/?series=281",
            "date": "2017-08-29T00:13:45",
            "name": "Patch Round-up for stable 2.9.1, freeze on 2017-09-04",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/281/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/806817/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/806817/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>",
        "X-Original-To": "incoming@patchwork.ozlabs.org",
        "Delivered-To": "patchwork-incoming@bilbo.ozlabs.org",
        "Authentication-Results": "ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=<UNKNOWN>)",
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            "from b01cxnp22033.gho.pok.ibm.com (9.57.198.23)\n\tby e12.ny.us.ibm.com (146.89.104.199) with IBM ESMTP SMTP Gateway:\n\tAuthorized Use Only! Violators will be prosecuted; \n\tMon, 28 Aug 2017 20:15:49 -0400",
            "from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com\n\t[9.57.199.106])\n\tby b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP\n\tid v7T0FmuQ24182974; Tue, 29 Aug 2017 00:15:48 GMT",
            "from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id 025E92803E;\n\tMon, 28 Aug 2017 20:15:42 -0400 (EDT)",
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        ],
        "From": "Michael Roth <mdroth@linux.vnet.ibm.com>",
        "To": "qemu-devel@nongnu.org",
        "Date": "Mon, 28 Aug 2017 19:13:54 -0500",
        "X-Mailer": "git-send-email 2.7.4",
        "In-Reply-To": "<1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com>",
        "References": "<1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com>",
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        "X-IBM-AV-DETECTION": "SAVI=unused REMOTE=unused XFE=unused",
        "x-cbparentid": "17082900-0049-0000-0000-000042619399",
        "Message-Id": "<1503965694-10794-20-git-send-email-mdroth@linux.vnet.ibm.com>",
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        "X-detected-operating-system": "by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy]",
        "X-Received-From": "148.163.156.1",
        "Subject": "[Qemu-devel] [PATCH 19/79] block: Reuse bs as backing hd for\n\tdrive-backup sync=none",
        "X-BeenThere": "qemu-devel@nongnu.org",
        "X-Mailman-Version": "2.1.21",
        "Precedence": "list",
        "List-Id": "<qemu-devel.nongnu.org>",
        "List-Unsubscribe": "<https://lists.nongnu.org/mailman/options/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.nongnu.org/archive/html/qemu-devel/>",
        "List-Post": "<mailto:qemu-devel@nongnu.org>",
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        "List-Subscribe": "<https://lists.nongnu.org/mailman/listinfo/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=subscribe>",
        "Cc": "Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>,\n\tqemu-stable@nongnu.org",
        "Errors-To": "qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org",
        "Sender": "\"Qemu-devel\"\n\t<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>"
    },
    "content": "From: Fam Zheng <famz@redhat.com>\n\nOpening the backing image for the second time is bad, especially here\nwhen it is also in use as the active image as the source. The\ndrive-backup job itself doesn't read from target->backing for COW,\ninstead it gets data from the write notifier, so it's not a big problem.\nHowever, exporting the target to NBD etc. won't work, because of the\nlikely stale metadata cache.\n\nUse BDRV_O_NO_BACKING in this case and manually set up the backing\nBdrvChild.\n\nCc: qemu-stable@nongnu.org\nSigned-off-by: Fam Zheng <famz@redhat.com>\nSigned-off-by: Kevin Wolf <kwolf@redhat.com>\n(cherry picked from commit fc0932fdcfc3e5cafa3641e361b681c07f639812)\nSigned-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>\n---\n blockdev.c | 15 ++++++++++++++-\n 1 file changed, 14 insertions(+), 1 deletion(-)",
    "diff": "diff --git a/blockdev.c b/blockdev.c\nindex e2f9c1e..841200e 100644\n--- a/blockdev.c\n+++ b/blockdev.c\n@@ -3170,6 +3170,7 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n     Error *local_err = NULL;\n     int flags;\n     int64_t size;\n+    bool set_backing_hd = false;\n \n     if (!backup->has_speed) {\n         backup->speed = 0;\n@@ -3220,6 +3221,8 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n     }\n     if (backup->sync == MIRROR_SYNC_MODE_NONE) {\n         source = bs;\n+        flags |= BDRV_O_NO_BACKING;\n+        set_backing_hd = true;\n     }\n \n     size = bdrv_getlength(bs);\n@@ -3246,7 +3249,9 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n     }\n \n     if (backup->format) {\n-        options = qdict_new();\n+        if (!options) {\n+            options = qdict_new();\n+        }\n         qdict_put_str(options, \"driver\", backup->format);\n     }\n \n@@ -3257,6 +3262,14 @@ static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,\n \n     bdrv_set_aio_context(target_bs, aio_context);\n \n+    if (set_backing_hd) {\n+        bdrv_set_backing_hd(target_bs, source, &local_err);\n+        if (local_err) {\n+            bdrv_unref(target_bs);\n+            goto out;\n+        }\n+    }\n+\n     if (backup->has_bitmap) {\n         bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);\n         if (!bmap) {\n",
    "prefixes": [
        "19/79"
    ]
}