Commit ba1de6cd authored by Yi Liu's avatar Yi Liu Committed by Jason Gunthorpe
Browse files

iommufd/device: Add helper to detect the first attach of a group 

The existing code detects the first attach by checking the
igroup->device_list. However, the igroup->hwpt can also be used to detect
the first attach. In future modifications, it is better to check the
igroup->hwpt instead of the device_list. To improve readbility and also
prepare for further modifications on this part, this adds a helper for it.

Link: https://patch.msgid.link/r/20250321171940.7213-7-yi.l.liu@intel.com


Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Signed-off-by: default avatarYi Liu <yi.l.liu@intel.com>
Tested-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 2eaa7f84

drivers/iommu/iommufd/device.c

+9 −2
Original line number Diff line number Diff line
@@ -329,6 +329,13 @@ iommufd_group_setup_msi(struct iommufd_group *igroup, 
}

#endif



static bool

iommufd_group_first_attach(struct iommufd_group *igroup, ioasid_t pasid)

{

	lockdep_assert_held(&igroup->lock);

	return !igroup->hwpt;

}



static int

iommufd_device_attach_reserved_iova(struct iommufd_device *idev,

				    struct iommufd_hwpt_paging *hwpt_paging)
@@ -344,7 +351,7 @@ iommufd_device_attach_reserved_iova(struct iommufd_device *idev, 
	if (rc)

		return rc;



	if (list_empty(&igroup->device_list)) {

	if (iommufd_group_first_attach(igroup, IOMMU_NO_PASID)) {

		rc = iommufd_group_setup_msi(igroup, hwpt_paging);

		if (rc) {

			iopt_remove_reserved_iova(&hwpt_paging->ioas->iopt,
@@ -508,7 +515,7 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, 
	 * reserved regions are only updated during individual device

	 * attachment.

	 */

	if (list_empty(&igroup->device_list)) {

	if (iommufd_group_first_attach(igroup, pasid)) {

		rc = iommufd_hwpt_attach_device(hwpt, idev, pasid);

		if (rc)

			goto err_unresv;