qga-win: Fix a bug where qemu-ga service is stuck during stop operation

After triggering a freeze command without any following thaw command,
qemu-ga will not respond to stop operation. This behaviour is wanted on Linux
as there is no time limit for a freeze command and we want to prevent
quitting in the middle of freeze, on the other hand on Windows the time
limit for freeze is 10 seconds, so we should wait for the timeout, thaw
the file system and quit.

Signed-off-by: Sameeh Jubran <sameeh@daynix.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/qga/main.c b/qga/main.c
index 07c295376fc230bea8639b8019bd19e0779e5e6f..ad6f68f187f83678d727fbbe648813980a1f08ff 100644 (file)
--- a/qga/main.c
+++ b/qga/main.c
@@ -131,9 +131,32 @@ static void quit_handler(int sig)
      * unless all log/pid files are on unfreezable filesystems. there's
      * also a very likely chance killing the agent before unfreezing
      * the filesystems is a mistake (or will be viewed as one later).
+     * On Windows the freeze interval is limited to 10 seconds, so
+     * we should quit, but first we should wait for the timeout, thaw
+     * the filesystem and quit.
      */
     if (ga_is_frozen(ga_state)) {
+#ifdef _WIN32
+        int i = 0;
+        Error *err = NULL;
+        HANDLE hEventTimeout;
+
+        g_debug("Thawing filesystems before exiting");
+
+        hEventTimeout = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_TIMEOUT);
+        if (hEventTimeout) {
+            WaitForSingleObject(hEventTimeout, 0);
+            CloseHandle(hEventTimeout);
+        }
+        qga_vss_fsfreeze(&i, false, &err);
+        if (err) {
+            g_debug("Error unfreezing filesystems prior to exiting: %s",
+                error_get_pretty(err));
+            error_free(err);
+        }
+#else
         return;
+#endif
     }
     g_debug("received signal num %d, quitting", sig);
 

diff --git a/qga/vss-win32.h b/qga/vss-win32.h
index 51d303a8f6b17426ffd37fd15ad7e4644d3cbe08..4f8e39aa5c5adc3f8a4d674001a6a5b282f96ca9 100644 (file)
--- a/qga/vss-win32.h
+++ b/qga/vss-win32.h
@@ -13,6 +13,7 @@
 #ifndef VSS_WIN32_H
 #define VSS_WIN32_H
 
+#include "qga/vss-win32/vss-handles.h"
 
 bool vss_init(bool init_requester);
 void vss_deinit(bool deinit_requester);

diff --git a/qga/vss-win32/vss-common.h b/qga/vss-win32/vss-common.h
index c81a8564b2a1e565bd85d63748fa9ad044bc0569..61c170b52e64ab54566bdffe26c17ddf2868f041 100644 (file)
--- a/qga/vss-win32/vss-common.h
+++ b/qga/vss-win32/vss-common.h
@@ -51,21 +51,12 @@
  * http://www.microsoft.com/en-us/download/details.aspx?id=23490
  */
 #include <inc/win2003/vss.h>
+#include "vss-handles.h"
 
 /* Macros to convert char definitions to wchar */
 #define _L(a) L##a
 #define L(a) _L(a)
 
-/* Constants for QGA VSS Provider */
-
-#define QGA_PROVIDER_NAME "QEMU Guest Agent VSS Provider"
-#define QGA_PROVIDER_LNAME L(QGA_PROVIDER_NAME)
-#define QGA_PROVIDER_VERSION L(QEMU_VERSION)
-
-#define EVENT_NAME_FROZEN  "Global\\QGAVSSEvent-frozen"
-#define EVENT_NAME_THAW    "Global\\QGAVSSEvent-thaw"
-#define EVENT_NAME_TIMEOUT "Global\\QGAVSSEvent-timeout"
-
 const GUID g_gProviderId = { 0x3629d4ed, 0xee09, 0x4e0e,
     {0x9a, 0x5c, 0x6d, 0x8b, 0xa2, 0x87, 0x2a, 0xef} };
 const GUID g_gProviderVersion = { 0x11ef8b15, 0xcac6, 0x40d6,

diff --git a/qga/vss-win32/vss-handles.h b/qga/vss-win32/vss-handles.h
new file mode 100644 (file)
index 0000000..ff399dd
--- /dev/null
+++ b/qga/vss-win32/vss-handles.h
@@ -0,0 +1,14 @@
+#ifndef VSS_HANDLES
+#define VSS_HANDLES
+
+/* Constants for QGA VSS Provider */
+
+#define QGA_PROVIDER_NAME "QEMU Guest Agent VSS Provider"
+#define QGA_PROVIDER_LNAME L(QGA_PROVIDER_NAME)
+#define QGA_PROVIDER_VERSION L(QEMU_VERSION)
+
+#define EVENT_NAME_FROZEN  "Global\\QGAVSSEvent-frozen"
+#define EVENT_NAME_THAW    "Global\\QGAVSSEvent-thaw"
+#define EVENT_NAME_TIMEOUT "Global\\QGAVSSEvent-timeout"
+
+#endif