lkml.org 
[lkml]   [2013]   [Feb]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3 1/3] VFIO: Wrapper for getting reference to vfio_device from device
Date

- Added vfio_device_get_from_dev() as wrapper to get
reference to vfio_device from struct device.

- Added vfio_device_data() as a wrapper to get device_data from
vfio_device.

Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
---
drivers/vfio/vfio.c | 41 ++++++++++++++++++++++++++++++++---------
include/linux/vfio.h | 3 +++
2 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 12c264d..f0a78a2 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -407,12 +407,13 @@ static void vfio_device_release(struct kref *kref)
}

/* Device reference always implies a group reference */
-static void vfio_device_put(struct vfio_device *device)
+void vfio_device_put(struct vfio_device *device)
{
struct vfio_group *group = device->group;
kref_put_mutex(&device->kref, vfio_device_release, &group->device_lock);
vfio_group_put(group);
}
+EXPORT_SYMBOL_GPL(vfio_device_put);

static void vfio_device_get(struct vfio_device *device)
{
@@ -642,8 +643,12 @@ int vfio_add_group_dev(struct device *dev,
}
EXPORT_SYMBOL_GPL(vfio_add_group_dev);

-/* Test whether a struct device is present in our tracking */
-static bool vfio_dev_present(struct device *dev)
+/**
+ * This does a get on the vfio_device from device.
+ * Callers of this function will have to call vfio_put_device() to
+ * remove the reference.
+ */
+struct vfio_device *vfio_device_get_from_dev(struct device *dev)
{
struct iommu_group *iommu_group;
struct vfio_group *group;
@@ -651,25 +656,43 @@ static bool vfio_dev_present(struct device *dev)

iommu_group = iommu_group_get(dev);
if (!iommu_group)
- return false;
+ return NULL;

group = vfio_group_get_from_iommu(iommu_group);
if (!group) {
iommu_group_put(iommu_group);
- return false;
+ return NULL;
}

device = vfio_group_get_device(group, dev);
if (!device) {
vfio_group_put(group);
iommu_group_put(iommu_group);
- return false;
+ return NULL;
}
-
- vfio_device_put(device);
vfio_group_put(group);
iommu_group_put(iommu_group);
- return true;
+ return device;
+}
+EXPORT_SYMBOL_GPL(vfio_device_get_from_dev);
+
+void *vfio_device_data(struct vfio_device *device)
+{
+ return device->device_data;
+}
+EXPORT_SYMBOL_GPL(vfio_device_data);
+
+/* Test whether a struct device is present in our tracking */
+static bool vfio_dev_present(struct device *dev)
+{
+ struct vfio_device *device;
+
+ device = vfio_device_get_from_dev(dev);
+ if (device) {
+ vfio_device_put(device);
+ return true;
+ } else
+ return false;
}

/*
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index ab9e862..ac8d488 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -45,6 +45,9 @@ extern int vfio_add_group_dev(struct device *dev,
void *device_data);

extern void *vfio_del_group_dev(struct device *dev);
+extern struct vfio_device *vfio_device_get_from_dev(struct device *dev);
+extern void vfio_device_put(struct vfio_device *device);
+extern void *vfio_device_data(struct vfio_device *device);

/**
* struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
--
1.7.11.3


\
 
 \ /
  Last update: 2013-02-03 15:41    [W:0.049 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site