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From f0623f334b23dc9334ac9d227cc467c266b8b2c6 Mon Sep 17 00:00:00 2001
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From: Fam Zheng <famz@redhat.com>
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Date: Wed, 9 Oct 2013 09:50:21 +0200
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Subject: [PATCH 09/11] block: don't lose data from last incomplete sector
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RH-Author: Fam Zheng <famz@redhat.com>
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Message-id: <1381312223-7074-2-git-send-email-famz@redhat.com>
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Patchwork-id: 54793
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O-Subject: [RHEL-7 qemu-kvm PATCH 1/3] block: don't lose data from last incomplete sector
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Bugzilla: 1017049
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RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
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RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
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RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
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To read the last sector that is not aligned to sector boundary, current
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code for growable backends, since commit 893a8f6 "block: Produce zeros
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when protocols reading beyond end of file", drops the data and directly
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returns zeroes. That is incorrect.
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Signed-off-by: Fam Zheng <famz@redhat.com>
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Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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(cherry picked from commit bcb9d66e8590151967e1dbe3724eec7ec71392e0)
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Signed-off-by: Fam Zheng <famz@redhat.com>
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---
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 block.c | 2 +-
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 1 file changed, 1 insertion(+), 1 deletion(-)
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 block.c |    2 +-
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 1 files changed, 1 insertions(+), 1 deletions(-)
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diff --git a/block.c b/block.c
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index a3bc800..bd52c13 100644
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--- a/block.c
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+++ b/block.c
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@@ -2567,7 +2567,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
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             goto out;
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         }
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-        total_sectors = len >> BDRV_SECTOR_BITS;
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+        total_sectors = (len + BDRV_SECTOR_SIZE - 1) >> BDRV_SECTOR_BITS;
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         max_nb_sectors = MAX(0, total_sectors - sector_num);
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         if (max_nb_sectors > 0) {
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             ret = drv->bdrv_co_readv(bs, sector_num,
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-- 
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1.7.1
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