From: Hao Peng <peng.hao2(a)zte.com.cn>
At present shared disks can be migrated with either readonly or cache=none. But
cache=directsync should be safe for migration, because both cache=directsync and
cache=none
don't use the host page cache, and cache=direct write through qemu block layer cache.
Signed-off-by: Peng Hao <peng.hao2(a)zte.com.cn>
Reviewed-by: Wang Yechao <wang.yechao255(a)zte.com.cn>
---
src/qemu/qemu_migration.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index c23fffe..9d509dd 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -1160,11 +1160,12 @@ qemuMigrationIsSafe(virDomainDefPtr def,
const char *src = virDomainDiskGetSource(disk);
/* Our code elsewhere guarantees shared disks are either readonly (in
- * which case cache mode doesn't matter) or used with cache=none */
+ * which case cache mode doesn't matter) or used with cache=none or used with
cache=directsync */
if (virStorageSourceIsEmpty(disk->src) ||
disk->src->readonly ||
disk->src->shared ||
- disk->cachemode == VIR_DOMAIN_DISK_CACHE_DISABLE)
+ disk->cachemode == VIR_DOMAIN_DISK_CACHE_DISABLE ||
+ disk->cachemode == VIR_DOMAIN_DISK_CACHE_DIRECTSYNC)
continue;
/* disks which are migrated by qemu are safe too */
@@ -1188,7 +1189,7 @@ qemuMigrationIsSafe(virDomainDefPtr def,
virReportError(VIR_ERR_MIGRATE_UNSAFE, "%s",
_("Migration may lead to data corruption if disks"
- " use cache != none"));
+ " use cache != none or cache != directsync"));
return false;
}
--
1.8.3.1
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