Logically the HWPT should have the coherency set properly for the device that it is being created for when it is created.
This was happening implicitly if the immediate_attach was set because iommufd_hw_pagetable_attach() does it as the first thing.
Do it unconditionally so !immediate_attach works properly.
Reviewed-by: Kevin Tian kevin.tian@intel.com Reviewed-by: Lu Baolu baolu.lu@linux.intel.com Tested-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com --- drivers/iommu/iommufd/device.c | 19 ++++------------- drivers/iommu/iommufd/hw_pagetable.c | 27 +++++++++++++++++++++++++ drivers/iommu/iommufd/iommufd_private.h | 1 + 3 files changed, 32 insertions(+), 15 deletions(-)
diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index 7db5df11ad9be3..d41e34d1b778dd 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -295,22 +295,11 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, goto err_unlock; }
- /* - * Try to upgrade the domain we have, it is an iommu driver bug to - * report IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail - * enforce_cache_coherency when there are no devices attached to the - * domain. - */ - if (idev->enforce_cache_coherency && !hwpt->enforce_cache_coherency) { - if (hwpt->domain->ops->enforce_cache_coherency) - hwpt->enforce_cache_coherency = - hwpt->domain->ops->enforce_cache_coherency( - hwpt->domain); - if (!hwpt->enforce_cache_coherency) { - WARN_ON(list_empty(&idev->igroup->device_list)); - rc = -EINVAL; + /* Try to upgrade the domain we have */ + if (idev->enforce_cache_coherency) { + rc = iommufd_hw_pagetable_enforce_cc(hwpt); + if (rc) goto err_unlock; - } }
rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev, diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index bdb76cdb1dc347..e0699d7f4c64af 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -25,6 +25,20 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj) refcount_dec(&hwpt->ioas->obj.users); }
+int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt) +{ + if (hwpt->enforce_cache_coherency) + return 0; + + if (hwpt->domain->ops->enforce_cache_coherency) + hwpt->enforce_cache_coherency = + hwpt->domain->ops->enforce_cache_coherency( + hwpt->domain); + if (!hwpt->enforce_cache_coherency) + return -EINVAL; + return 0; +} + /** * iommufd_hw_pagetable_alloc() - Get an iommu_domain for a device * @ictx: iommufd context @@ -60,6 +74,19 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, goto out_abort; }
+ /* + * Set the coherency mode before we do iopt_table_add_domain() as some + * iommus have a per-PTE bit that controls it and need to decide before + * doing any maps. It is an iommu driver bug to report + * IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail enforce_cache_coherency on + * a new domain. + */ + if (idev->enforce_cache_coherency) { + rc = iommufd_hw_pagetable_enforce_cc(hwpt); + if (WARN_ON(rc)) + goto out_abort; + } + /* * immediate_attach exists only to accommodate iommu drivers that cannot * directly allocate a domain. These drivers do not finish creating the diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 63b2587a37f23d..5ce9eaf5fb88e3 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -254,6 +254,7 @@ struct iommufd_hw_pagetable { struct iommufd_hw_pagetable * iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, struct iommufd_device *idev, bool immediate_attach); +int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt); int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, struct iommufd_device *idev); struct iommufd_hw_pagetable *