[PATCH v4 07/12] Drivers: hv: vmbus: Implement suspend/resume for VSC drivers for hibernation

From: Dexuan Cui
Date: Mon Sep 02 2019 - 20:23:31 EST


The high-level VSC drivers will implement device-specific callbacks.

Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
include/linux/hyperv.h | 3 +++
2 files changed, 49 insertions(+)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 2ef375c..a30c70a 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -911,6 +911,43 @@ static void vmbus_shutdown(struct device *child_device)
drv->shutdown(dev);
}

+/*
+ * vmbus_suspend - Suspend a vmbus device
+ */
+static int vmbus_suspend(struct device *child_device)
+{
+ struct hv_driver *drv;
+ struct hv_device *dev = device_to_hv_device(child_device);
+
+ /* The device may not be attached yet */
+ if (!child_device->driver)
+ return 0;
+
+ drv = drv_to_hv_drv(child_device->driver);
+ if (!drv->suspend)
+ return -EOPNOTSUPP;
+
+ return drv->suspend(dev);
+}
+
+/*
+ * vmbus_resume - Resume a vmbus device
+ */
+static int vmbus_resume(struct device *child_device)
+{
+ struct hv_driver *drv;
+ struct hv_device *dev = device_to_hv_device(child_device);
+
+ /* The device may not be attached yet */
+ if (!child_device->driver)
+ return 0;
+
+ drv = drv_to_hv_drv(child_device->driver);
+ if (!drv->resume)
+ return -EOPNOTSUPP;
+
+ return drv->resume(dev);
+}

/*
* vmbus_device_release - Final callback release of the vmbus child device
@@ -926,6 +963,14 @@ static void vmbus_device_release(struct device *device)
kfree(hv_dev);
}

+/*
+ * Note: we must use SET_NOIRQ_SYSTEM_SLEEP_PM_OPS rather than
+ * SET_SYSTEM_SLEEP_PM_OPS: see the comment before vmbus_bus_pm.
+ */
+static const struct dev_pm_ops vmbus_pm = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(vmbus_suspend, vmbus_resume)
+};
+
/* The one and only one */
static struct bus_type hv_bus = {
.name = "vmbus",
@@ -936,6 +981,7 @@ static void vmbus_device_release(struct device *device)
.uevent = vmbus_uevent,
.dev_groups = vmbus_dev_groups,
.drv_groups = vmbus_drv_groups,
+ .pm = &vmbus_pm,
};

struct onmessage_work_context {
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 2d39248..8a60e77 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1157,6 +1157,9 @@ struct hv_driver {
int (*remove)(struct hv_device *);
void (*shutdown)(struct hv_device *);

+ int (*suspend)(struct hv_device *);
+ int (*resume)(struct hv_device *);
+
};

/* Base device object */
--
1.8.3.1