| Message ID | 20221110014027.28780-3-ajderossi@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio/pci: Check the device set open count on reset | expand |
On 2022/11/10 09:40, Anthony DeRossi wrote: > The open count of a device set is the sum of the open counts of all > devices in the set. Drivers can use this value to determine whether > shared resources are in use without tracking them manually or accessing > the private open_count in vfio_device. > > Signed-off-by: Anthony DeRossi <ajderossi@gmail.com> > Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> > Reviewed-by: Kevin Tian <kevin.tian@intel.com> > --- > drivers/vfio/vfio_main.c | 13 +++++++++++++ > include/linux/vfio.h | 1 + > 2 files changed, 14 insertions(+) Reviewed-by: Yi Liu <yi.l.liu@intel.com> > diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c > index 9a4af880e941..6e8804fe0095 100644 > --- a/drivers/vfio/vfio_main.c > +++ b/drivers/vfio/vfio_main.c > @@ -125,6 +125,19 @@ static void vfio_release_device_set(struct vfio_device *device) > xa_unlock(&vfio_device_set_xa); > } > > +unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set) > +{ > + struct vfio_device *cur; > + unsigned int open_count = 0; > + > + lockdep_assert_held(&dev_set->lock); > + > + list_for_each_entry(cur, &dev_set->device_list, dev_set_list) > + open_count += cur->open_count; > + return open_count; > +} > +EXPORT_SYMBOL_GPL(vfio_device_set_open_count); > + > /* > * Group objects - create, release, get, put, search > */ > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index e7cebeb875dd..fdd393f70b19 100644 > --- a/include/linux/vfio.h > +++ b/include/linux/vfio.h > @@ -189,6 +189,7 @@ int vfio_register_emulated_iommu_dev(struct vfio_device *device); > void vfio_unregister_group_dev(struct vfio_device *device); > > int vfio_assign_device_set(struct vfio_device *device, void *set_id); > +unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set); > > int vfio_mig_get_next_state(struct vfio_device *device, > enum vfio_device_mig_state cur_fsm,
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 9a4af880e941..6e8804fe0095 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -125,6 +125,19 @@ static void vfio_release_device_set(struct vfio_device *device) xa_unlock(&vfio_device_set_xa); } +unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set) +{ + struct vfio_device *cur; + unsigned int open_count = 0; + + lockdep_assert_held(&dev_set->lock); + + list_for_each_entry(cur, &dev_set->device_list, dev_set_list) + open_count += cur->open_count; + return open_count; +} +EXPORT_SYMBOL_GPL(vfio_device_set_open_count); + /* * Group objects - create, release, get, put, search */ diff --git a/include/linux/vfio.h b/include/linux/vfio.h index e7cebeb875dd..fdd393f70b19 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -189,6 +189,7 @@ int vfio_register_emulated_iommu_dev(struct vfio_device *device); void vfio_unregister_group_dev(struct vfio_device *device); int vfio_assign_device_set(struct vfio_device *device, void *set_id); +unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set); int vfio_mig_get_next_state(struct vfio_device *device, enum vfio_device_mig_state cur_fsm,