Blame SOURCES/kvm-block-Set-BDRV_REQ_WRITE_UNCHANGED-for-COR-writes.patch

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From 5e44d51d7631be589579e5e3c4dece9f651257ab Mon Sep 17 00:00:00 2001
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From: Max Reitz <mreitz@redhat.com>
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Date: Mon, 18 Jun 2018 16:12:07 +0200
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Subject: [PATCH 31/54] block: Set BDRV_REQ_WRITE_UNCHANGED for COR writes
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RH-Author: Max Reitz <mreitz@redhat.com>
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Message-id: <20180618161212.14444-6-mreitz@redhat.com>
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Patchwork-id: 80766
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O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH 05/10] block: Set BDRV_REQ_WRITE_UNCHANGED for COR writes
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Bugzilla: 1518738
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RH-Acked-by: John Snow <jsnow@redhat.com>
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RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
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RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
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Signed-off-by: Max Reitz <mreitz@redhat.com>
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Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
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Reviewed-by: Alberto Garcia <berto@igalia.com>
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Message-id: 20180421132929.21610-5-mreitz@redhat.com
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Reviewed-by: Kevin Wolf <kwolf@redhat.com>
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Signed-off-by: Max Reitz <mreitz@redhat.com>
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(cherry picked from commit 7adcf59fecf3c8ce9330430187350b53f9e50cf7)
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Signed-off-by: Max Reitz <mreitz@redhat.com>
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 block/io.c | 6 ++++--
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 1 file changed, 4 insertions(+), 2 deletions(-)
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diff --git a/block/io.c b/block/io.c
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index 134b2a4..fada4ef 100644
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--- a/block/io.c
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+++ b/block/io.c
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@@ -1115,13 +1115,15 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,
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                 /* FIXME: Should we (perhaps conditionally) be setting
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                  * BDRV_REQ_MAY_UNMAP, if it will allow for a sparser copy
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                  * that still correctly reads as zero? */
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-                ret = bdrv_co_do_pwrite_zeroes(bs, cluster_offset, pnum, 0);
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+                ret = bdrv_co_do_pwrite_zeroes(bs, cluster_offset, pnum,
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+                                               BDRV_REQ_WRITE_UNCHANGED);
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             } else {
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                 /* This does not change the data on the disk, it is not
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                  * necessary to flush even in cache=writethrough mode.
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                  */
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                 ret = bdrv_driver_pwritev(bs, cluster_offset, pnum,
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-                                          &local_qiov, 0);
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+                                          &local_qiov,
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+                                          BDRV_REQ_WRITE_UNCHANGED);
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             }
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             if (ret < 0) {
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-- 
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1.8.3.1
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