[PATCH v2 1/8] iommu/vt-d: Allocate pasid table in device probe path

Lu Baolu
2022-11-08T07:42:01Z

Whether or not a domain is attached to the device, the pasid table should
always be valid as long as it has been probed. This moves the pasid table
allocation from the domain attaching device path to device probe path and
frees it in the device release path.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---
drivers/iommu/intel/iommu.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index f298e51d5aa6..bc42a2c84e2a 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2477,13 +2477,6 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev)

/* PASID table is mandatory for a PCI device in scalable mode. */
if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) {
- ret = intel_pasid_alloc_table(dev);
- if (ret) {
- dev_err(dev, "PASID table allocation failed\n");
- dmar_remove_one_dev_info(dev);
- return ret;
- }
-
/* Setup the PASID entry for requests without PASID: */
if (hw_pass_through && domain_type_is_si(domain))
ret = intel_pasid_setup_pass_through(iommu, domain,
@@ -4108,7 +4101,6 @@ static void dmar_remove_one_dev_info(struct device *dev)

iommu_disable_dev_iotlb(info);
domain_context_clear(info);
- intel_pasid_free_table(info->dev);
}

spin_lock_irqsave(&domain->lock, flags);
@@ -4466,6 +4458,7 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)
struct device_domain_info *info;
struct intel_iommu *iommu;
u8 bus, devfn;
+ int ret;

iommu = device_to_iommu(dev, &bus, &devfn);
if (!iommu || !iommu->iommu.ops)
@@ -4509,6 +4502,16 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)

dev_iommu_priv_set(dev, info);

+ if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) {
+ ret = intel_pasid_alloc_table(dev);
+ if (ret) {
+ dev_err(dev, "PASID table allocation failed\n");
+ dev_iommu_priv_set(dev, NULL);
+ kfree(info);
+ return ERR_PTR(ret);
+ }
+ }
+
return &iommu->iommu;
}

@@ -4517,6 +4520,7 @@ static void intel_iommu_release_device(struct device *dev)
struct device_domain_info *info = dev_iommu_priv_get(dev);

dmar_remove_one_dev_info(dev);
+ intel_pasid_free_table(dev);
dev_iommu_priv_set(dev, NULL);
kfree(info);
set_dma_ops(dev, NULL);
--
2.34.1