[PATCH 3/7] iommu/vt-d: Use device_block_translation() in dev_attach error path

From: Lu Baolu
Date: Thu Nov 03 2022 - 02:00:36 EST


If domain attaching to device fails, the IOMMU driver should bring the
device to blocking DMA state. The upper layer is expected to recover it
by attaching a new domain. Use device_block_translation() in the error
path of dev_attach to make the behavior specific.

The difference between device_block_translation() and the previous
dmar_remove_one_dev_info() is that the latter disables PCIe ATS and the
related PCIe features. This is unnecessary as these features are not per
domain capabilities, disabling them during domain switching is
unnecessary.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 7374a03cbe27..b956c411f2bb 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -277,8 +277,8 @@ static LIST_HEAD(dmar_satc_units);
#define for_each_rmrr_units(rmrr) \
list_for_each_entry(rmrr, &dmar_rmrr_units, list)

-static void dmar_remove_one_dev_info(struct device *dev);
static void intel_iommu_domain_free(struct iommu_domain *domain);
+static void device_block_translation(struct device *dev);

int dmar_disabled = !IS_ENABLED(CONFIG_INTEL_IOMMU_DEFAULT_ON);
int intel_iommu_sm = IS_ENABLED(CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON);
@@ -2490,7 +2490,7 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev)
dev, PASID_RID2PASID);
if (ret) {
dev_err(dev, "Setup RID2PASID failed\n");
- dmar_remove_one_dev_info(dev);
+ device_block_translation(dev);
return ret;
}
}
@@ -2498,7 +2498,7 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev)
ret = domain_context_mapping(domain, dev);
if (ret) {
dev_err(dev, "Domain context map failed\n");
- dmar_remove_one_dev_info(dev);
+ device_block_translation(dev);
return ret;
}

@@ -4283,7 +4283,7 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
struct device_domain_info *info = dev_iommu_priv_get(dev);

if (info->domain)
- dmar_remove_one_dev_info(dev);
+ device_block_translation(dev);
}

ret = prepare_domain_attach_device(domain, dev);
--
2.34.1