Drivers: hv: Add a new driver to support host initiated backup
This driver supports host initiated backup of the guest. On Windows guests,
the host can generate application consistent backups using the Windows VSS
framework. On Linux, we ensure that the backup will be file system consistent.
This driver allows the host to initiate a "Freeze" operation on all the mounted
file systems in the guest. Once the mounted file systems in the guest are frozen,
the host snapshots the guest's file systems. Once this is done, the guest's file
systems are "thawed".
This driver has a user-level component (daemon) that invokes the appropriate
operation on all the mounted file systems in response to the requests from
the host. The duration for which the guest is frozen is very short - a few seconds.
During this interval, the diff disk is comitted.
In this version of the patch I have addressed the feedback from Olaf Herring.
Also, some of the connector related issues have been fixed.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/uapi/linux/connector.h b/include/uapi/linux/connector.h
index 8761a03..4cb2835 100644
--- a/include/uapi/linux/connector.h
+++ b/include/uapi/linux/connector.h
@@ -44,8 +44,11 @@
#define CN_VAL_DRBD 0x1
#define CN_KVP_IDX 0x9 /* HyperV KVP */
#define CN_KVP_VAL 0x1 /* queries from the kernel */
+#define CN_VSS_IDX 0xA /* HyperV VSS */
+#define CN_VSS_VAL 0x1 /* queries from the kernel */
-#define CN_NETLINK_USERS 10 /* Highest index + 1 */
+
+#define CN_NETLINK_USERS 11 /* Highest index + 1 */
/*
* Maximum connector's message size.