From 44f507163d9e51238458ee6904b4d71fb0723723 Mon Sep 17 00:00:00 2001 From: Vijay Mohan Pandarathil Date: Mon, 11 Mar 2013 09:28:44 -0600 Subject: 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 Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) (limited to 'drivers/vfio/vfio.c') diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index fcc12f3e60a..21eddd9e0f2 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) { -- cgit v1.2.3