diff options
| author | Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com> | 2013-03-11 09:28:44 -0600 |
|---|---|---|
| committer | Alex Williamson <alex.williamson@redhat.com> | 2013-03-11 09:28:44 -0600 |
| commit | 44f507163d9e51238458ee6904b4d71fb0723723 (patch) | |
| tree | ddd48ebd567813495ddeb718d7d54524f16f313f | |
| parent | f6161aa153581da4a3867a2d1a7caf4be19b6ec9 (diff) | |
| download | linux-44f507163d9e51238458ee6904b4d71fb0723723.tar.gz linux-44f507163d9e51238458ee6904b4d71fb0723723.tar.bz2 linux-44f507163d9e51238458ee6904b4d71fb0723723.zip | |
VFIO: Wrapper for getting reference to vfio_device
- 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>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
| -rw-r--r-- | drivers/vfio/vfio.c | 30 | ||||
| -rw-r--r-- | include/linux/vfio.h | 3 |
2 files changed, 32 insertions, 1 deletions
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index fcc12f3e60a3..21eddd9e0f26 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -392,12 +392,13 @@ 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) { @@ -627,6 +628,33 @@ int vfio_add_group_dev(struct device *dev, } EXPORT_SYMBOL_GPL(vfio_add_group_dev); +/** + * Get a reference to the vfio_device for a device that is known to + * be bound to a vfio driver. The driver implicitly holds a + * vfio_device reference between vfio_add_group_dev and + * vfio_del_group_dev. We can therefore use drvdata to increment + * that reference from the struct device. This additional + * reference must be released by calling vfio_device_put. + */ +struct vfio_device *vfio_device_get_from_dev(struct device *dev) +{ + struct vfio_device *device = dev_get_drvdata(dev); + + vfio_device_get(device); + + return device; +} +EXPORT_SYMBOL_GPL(vfio_device_get_from_dev); + +/* + * Caller must hold a reference to the vfio_device + */ +void *vfio_device_data(struct vfio_device *device) +{ + return device->device_data; +} +EXPORT_SYMBOL_GPL(vfio_device_data); + /* Given a referenced group, check if it contains the device */ static bool vfio_dev_present(struct vfio_group *group, struct device *dev) { diff --git a/include/linux/vfio.h b/include/linux/vfio.h index ab9e86224c54..ac8d488e4372 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 |