qemu/0017-xen_disk-Add-suse-specific-flush-di.patch
2017-10-03 22:19:51 +00:00

66 lines
2.0 KiB
Diff

From 6fb43092cfca3e96c07ad78727a6b78a1d3b981f Mon Sep 17 00:00:00 2001
From: Bruce Rogers <brogers@suse.com>
Date: Wed, 9 Mar 2016 15:18:11 -0700
Subject: [PATCH] xen_disk: Add suse specific flush disable handling and map to
QEMU equiv
Add code to read the suse specific suse-diskcache-disable-flush flag out
of xenstore, and set the equivalent flag within QEMU.
Patch taken from Xen's patch queue, Olaf Hering being the original author.
[bsc#879425]
Signed-off-by: Bruce Rogers <brogers@suse.com>
Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
hw/block/xen_disk.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c
index d42ed7070d..0dc524903e 100644
--- a/hw/block/xen_disk.c
+++ b/hw/block/xen_disk.c
@@ -113,6 +113,7 @@ struct XenBlkDev {
int requests_finished;
unsigned int max_requests;
+ gboolean cache_unsafe;
/* Persistent grants extension */
gboolean feature_discard;
gboolean feature_persistent;
@@ -947,6 +948,16 @@ static void blk_parse_discard(struct XenBlkDev *blkdev)
}
}
+static void blk_parse_cache_unsafe(struct XenBlkDev *blkdev)
+{
+ int enable;
+
+ blkdev->cache_unsafe = false;
+
+ if (xenstore_read_be_int(&blkdev->xendev, "suse-diskcache-disable-flush", &enable) == 0)
+ blkdev->cache_unsafe = !!enable;
+}
+
static int blk_init(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
@@ -1028,6 +1039,7 @@ static int blk_init(struct XenDevice *xendev)
MAX_RING_PAGE_ORDER);
blk_parse_discard(blkdev);
+ blk_parse_cache_unsafe(blkdev);
g_free(directiosafe);
return 0;
@@ -1083,6 +1095,9 @@ static int blk_connect(struct XenDevice *xendev)
qflags |= BDRV_O_UNMAP;
}
+ if (blkdev->cache_unsafe)
+ qflags |= BDRV_O_NO_FLUSH;
+
/* init qemu block driver */
index = (blkdev->xendev.dev - 202 * 256) / 16;
blkdev->dinfo = drive_get(IF_XEN, 0, index);