From: Andreas Färber <afaerber@suse.de>
Date: Wed, 5 Jun 2013 13:17:57 +0000 (+0200)
Subject: ide: Set BSY bit during FLUSH
X-Git-Tag: v1.6.0-rc0~246^2~6
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f68ec837;p=thirdparty%2Fqemu.git

ide: Set BSY bit during FLUSH

The implementation of the ATA FLUSH command invokes a flush at the block
layer, which may on raw files on POSIX entail a synchronous fdatasync().
This may in some cases take so long that the SLES 11 SP1 guest driver
reports I/O errors and filesystems get corrupted or remounted read-only.

Avoid this by setting BUSY_STAT, so that the guest is made aware we are
in the middle of an operation and no ATA commands are attempted to be
processed concurrently.

Addresses BNC#637297.

Suggested-by: Gonglei (Arei) <arei.gonglei@huawei.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---

diff --git a/hw/ide/core.c b/hw/ide/core.c
index c7a80413be5..9926d9202bc 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -814,6 +814,7 @@ void ide_flush_cache(IDEState *s)
         return;
     }
 
+    s->status |= BUSY_STAT;
     bdrv_acct_start(s->bs, &s->acct, 0, BDRV_ACCT_FLUSH);
     bdrv_aio_flush(s->bs, ide_flush_cb, s);
 }