[PATCH 2/3] hv_utils: Support host-initiated hibernation request

From: Dexuan Cui
Date: Wed Sep 11 2019 - 19:39:09 EST


Update the Shutdown IC version to 3.2, which is required for the host to
send the hibernation request.

The user is expected to create the program "/sbin/hyperv-hibernate", which
is called on the host-initiated hibernation request.

The program can be a script like

test@localhost:~$ cat /sbin/hyperv-hibernate
#!/bin/bash
echo disk > /sys/power/state

Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
---
drivers/hv/hv_util.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 65 insertions(+), 1 deletion(-)

diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index 039c752..9e98c5d 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -24,6 +24,8 @@

#define SD_MAJOR 3
#define SD_MINOR 0
+#define SD_MINOR_2 2
+#define SD_VERSION_3_2 (SD_MAJOR << 16 | SD_MINOR_2)
#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)

#define SD_MAJOR_1 1
@@ -50,8 +52,9 @@
static int ts_srv_version;
static int hb_srv_version;

-#define SD_VER_COUNT 2
+#define SD_VER_COUNT 3
static const int sd_versions[] = {
+ SD_VERSION_3_2,
SD_VERSION,
SD_VERSION_1
};
@@ -75,9 +78,30 @@
UTIL_WS2K8_FW_VERSION
};

+static bool execute_hibernate;
+static int hv_shutdown_init(struct hv_util_service *srv)
+{
+#if 0
+ /*
+ * The patch to implement hv_is_hibernation_supported() is going
+ * through the tip tree. For now, let's hardcode execute_hibernate
+ * to true -- this doesn't break anything since hibernation for
+ * Linux VM on Hyper-V never worked before. We'll remove the
+ * conditional compilation as soon as hv_is_hibernation_supported()
+ * is available in the mainline tree.
+ */
+ execute_hibernate = hv_is_hibernation_supported();
+#else
+ execute_hibernate = true;
+#endif
+
+ return 0;
+}
+
static void shutdown_onchannelcallback(void *context);
static struct hv_util_service util_shutdown = {
.util_cb = shutdown_onchannelcallback,
+ .util_init = hv_shutdown_init,
};

static int hv_timesync_init(struct hv_util_service *srv);
@@ -123,11 +147,38 @@ static void perform_shutdown(struct work_struct *dummy)
orderly_poweroff(true);
}

+static void perform_hibernation(struct work_struct *dummy)
+{
+ /*
+ * The user is expected to create the program, which can be a simple
+ * script containing two lines:
+ * #!/bin/bash
+ * echo disk > /sys/power/state
+ */
+ static char hibernate_cmd[PATH_MAX] = "/sbin/hyperv-hibernate";
+
+ static char *envp[] = {
+ NULL,
+ };
+
+ static char *argv[] = {
+ hibernate_cmd,
+ NULL,
+ };
+
+ call_usermodehelper(hibernate_cmd, argv, envp, UMH_NO_WAIT);
+}
+
/*
* Perform the shutdown operation in a thread context.
*/
static DECLARE_WORK(shutdown_work, perform_shutdown);

+/*
+ * Perform the hibernation operation in a thread context.
+ */
+static DECLARE_WORK(hibernate_work, perform_hibernation);
+
static void shutdown_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
@@ -171,6 +222,19 @@ static void shutdown_onchannelcallback(void *context)
pr_info("Shutdown request received -"
" graceful shutdown initiated\n");
break;
+ case 4:
+ case 5:
+ pr_info("Hibernation request received -"
+ " hibernation %sinitiated\n",
+ execute_hibernate ? "" : "not ");
+
+ if (execute_hibernate) {
+ icmsghdrp->status = HV_S_OK;
+ schedule_work(&hibernate_work);
+ } else {
+ icmsghdrp->status = HV_E_FAIL;
+ }
+ break;
default:
icmsghdrp->status = HV_E_FAIL;
execute_shutdown = false;
--
1.8.3.1