[PATCH 1/4] iommu/vt-d: Fix error handling in sva enable/disable paths

[Lu Baolu <baolu.lu@linux.intel.com>]

Roll back all previous actions in error paths of intel_iommu_enable_sva()
and intel_iommu_disable_sva().

Fixes: d5b9e4bfe0d8 ("iommu/vt-d: Report prq to io-pgfault framework")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230208051559.700109-1-baolu.lu@linux.intel.com
---
 drivers/iommu/intel/iommu.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 59df7e42fd53..994dffa1db57 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4642,8 +4642,12 @@ static int intel_iommu_enable_sva(struct device *dev)
 		return -EINVAL;
 
 	ret = iopf_queue_add_device(iommu->iopf_queue, dev);
-	if (!ret)
-		ret = iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev);
+	if (ret)
+		return ret;
+
+	ret = iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev);
+	if (ret)
+		iopf_queue_remove_device(iommu->iopf_queue, dev);
 
 	return ret;
 }
@@ -4655,8 +4659,12 @@ static int intel_iommu_disable_sva(struct device *dev)
 	int ret;
 
 	ret = iommu_unregister_device_fault_handler(dev);
-	if (!ret)
-		ret = iopf_queue_remove_device(iommu->iopf_queue, dev);
+	if (ret)
+		return ret;
+
+	ret = iopf_queue_remove_device(iommu->iopf_queue, dev);
+	if (ret)
+		iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev);
 
 	return ret;
 }
-- 
2.34.1