On 11/6/24 23:45, Yi Liu wrote:
+int intel_pasid_replace_first_level(struct intel_iommu *iommu,
+ struct device *dev, pgd_t *pgd,
+ u32 pasid, u16 did, u16 old_did,
+ int flags)
+{
+ struct pasid_entry *pte;
+
+ if (!ecap_flts(iommu->ecap)) {
+ pr_err("No first level translation support on %s\n",
+ iommu->name);
+ return -EINVAL;
+ }
+
+ if ((flags & PASID_FLAG_FL5LP) && !cap_fl5lp_support(iommu->cap)) {
+ pr_err("No 5-level paging support for first-level on %s\n",
+ iommu->name);
+ return -EINVAL;
+ }
+
+ spin_lock(&iommu->lock);
+ pte = intel_pasid_get_entry(dev, pasid);
+ if (!pte) {
+ spin_unlock(&iommu->lock);
+ return -ENODEV;
+ }
+
+ if (!pasid_pte_is_present(pte)) {
+ spin_unlock(&iommu->lock);
+ return -EINVAL;
+ }
+
+ WARN_ON(old_did != pasid_get_domain_id(pte));
+
+ pasid_pte_config_first_level(iommu, pte, pgd, did, flags);
+ spin_unlock(&iommu->lock);
+
+ intel_pasid_flush_present(iommu, dev, pasid, old_did, pte);
+ intel_iommu_drain_pasid_prq(dev, pasid);
+
+ return 0;
+}
pasid_pte_config_first_level() causes the pasid entry to transition from
present to non-present and then to present. In this case, calling
intel_pasid_flush_present() is not accurate, as it is only intended for
pasid entries transitioning from present to present, according to the
specification.
It's recommended to move pasid_clear_entry(pte) and
pasid_set_present(pte) out to the caller, so ...
For setup case (pasid from non-present to present):
- pasid_clear_entry(pte)
- pasid_pte_config_first_level(pte)
- pasid_set_present(pte)
- cache invalidations
For replace case (pasid from present to present)
- pasid_pte_config_first_level(pte)
- cache invalidations
The same applies to other types of setup and replace.
--
baolu
