From: Yi Liu <yi.l.liu@intel.com>
Date: Sun, 8 Sep 2024 11:42:55 +0000 (-0700)
Subject: iommufd: Avoid duplicated __iommu_group_set_core_domain() call
X-Git-Tag: v6.12-rc1~71^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d9dfb5e6225a0a99e08dc2a538b0c30a5a9a460c;p=thirdparty%2Flinux.git

iommufd: Avoid duplicated __iommu_group_set_core_domain() call

For the fault-capable hwpts, the iommufd_hwpt_detach_device() calls both
iommufd_fault_domain_detach_dev() and iommu_detach_group(). This would have
duplicated __iommu_group_set_core_domain() call since both functions call
it in the end. This looks no harm as the __iommu_group_set_core_domain()
returns if the new domain equals to the existing one. But it makes sense to
avoid such duplicated calls in caller side.

Link: https://patch.msgid.link/r/20240908114256.979518-2-yi.l.liu@intel.com
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---

diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 5d3768d770992..f1d865e6fab66 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -510,8 +510,10 @@ static inline int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt,
 static inline void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt,
 					      struct iommufd_device *idev)
 {
-	if (hwpt->fault)
+	if (hwpt->fault) {
 		iommufd_fault_domain_detach_dev(hwpt, idev);
+		return;
+	}
 
 	iommu_detach_group(hwpt->domain, idev->igroup->group);
 }