A new SET_OPTION will reuse this helper for a sanity check before setting a per-idev property.
Given that the attach handle can be NULL if device is not attached, add a pointer check prior to the xa_load(). This is not a problem currently, as the only caller iommufd_device_do_replace() verifies the attach handle. Also, add lockdep_assert_held on igroup's mutex; Signed-off-by: Nicolin Chen <[email protected]> --- drivers/iommu/iommufd/iommufd_private.h | 1 + drivers/iommu/iommufd/device.c | 7 ++++--- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index cc758610b9f7c..c458ab16736b6 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -502,6 +502,7 @@ iommufd_get_device(struct iommufd_ucmd *ucmd, u32 id) void iommufd_device_pre_destroy(struct iommufd_object *obj); void iommufd_device_destroy(struct iommufd_object *obj); +bool iommufd_device_is_attached(struct iommufd_device *idev, ioasid_t pasid); int iommufd_get_hw_info(struct iommufd_ucmd *ucmd); struct iommufd_access { diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index 2a816533dc10e..45a1d1603c009 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -436,13 +436,14 @@ iommufd_device_attach_reserved_iova(struct iommufd_device *idev, /* The device attach/detach/replace helpers for attach_handle */ -static bool iommufd_device_is_attached(struct iommufd_device *idev, - ioasid_t pasid) +bool iommufd_device_is_attached(struct iommufd_device *idev, ioasid_t pasid) { struct iommufd_attach *attach; + lockdep_assert_held(&idev->igroup->lock); + attach = xa_load(&idev->igroup->pasid_attach, pasid); - return xa_load(&attach->device_array, idev->obj.id); + return attach && xa_load(&attach->device_array, idev->obj.id); } static int iommufd_hwpt_pasid_compat(struct iommufd_hw_pagetable *hwpt, -- 2.43.0
