[PATCH v3 09/12] iommu/vt-d: Use cache helpers in arch_invalidate_secondary_tlbs

From: Lu Baolu
Date: Tue Apr 16 2024 - 04:10:37 EST


The arch_invalidate_secondary_tlbs callback is called in the SVA mm
notification path. It invalidates all or a range of caches after the
CPU page table is modified. Use the cache tag helps in this path.

The mm_types defines vm_end as the first byte after the end address
which is different from the iommu gather API, hence convert the end
parameter from mm_types to iommu gather scheme before calling the
cache_tag helper.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/iommu.h | 1 +
drivers/iommu/intel/svm.c | 81 +++++--------------------------------
2 files changed, 11 insertions(+), 71 deletions(-)

diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index b1d04aa36d31..31bbce8ffe7e 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -1167,6 +1167,7 @@ struct intel_svm {
struct mm_struct *mm;
u32 pasid;
struct list_head devs;
+ struct dmar_domain *domain;
};
#else
static inline void intel_svm_check(struct intel_iommu *iommu) {}
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 641d0cef3737..e6d25a0f25f6 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -168,88 +168,25 @@ void intel_svm_check(struct intel_iommu *iommu)
iommu->flags |= VTD_FLAG_SVM_CAPABLE;
}

-static void __flush_svm_range_dev(struct intel_svm *svm,
- struct intel_svm_dev *sdev,
- unsigned long address,
- unsigned long pages, int ih)
-{
- struct device_domain_info *info = dev_iommu_priv_get(sdev->dev);
-
- if (WARN_ON(!pages))
- return;
-
- qi_flush_piotlb(sdev->iommu, sdev->did, svm->pasid, address, pages, ih);
- if (info->ats_enabled) {
- qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid,
- svm->pasid, sdev->qdep, address,
- order_base_2(pages));
- quirk_extra_dev_tlb_flush(info, address, order_base_2(pages),
- svm->pasid, sdev->qdep);
- }
-}
-
-static void intel_flush_svm_range_dev(struct intel_svm *svm,
- struct intel_svm_dev *sdev,
- unsigned long address,
- unsigned long pages, int ih)
-{
- unsigned long shift = ilog2(__roundup_pow_of_two(pages));
- unsigned long align = (1ULL << (VTD_PAGE_SHIFT + shift));
- unsigned long start = ALIGN_DOWN(address, align);
- unsigned long end = ALIGN(address + (pages << VTD_PAGE_SHIFT), align);
-
- while (start < end) {
- __flush_svm_range_dev(svm, sdev, start, align >> VTD_PAGE_SHIFT, ih);
- start += align;
- }
-}
-
-static void intel_flush_svm_range(struct intel_svm *svm, unsigned long address,
- unsigned long pages, int ih)
-{
- struct intel_svm_dev *sdev;
-
- rcu_read_lock();
- list_for_each_entry_rcu(sdev, &svm->devs, list)
- intel_flush_svm_range_dev(svm, sdev, address, pages, ih);
- rcu_read_unlock();
-}
-
-static void intel_flush_svm_all(struct intel_svm *svm)
-{
- struct device_domain_info *info;
- struct intel_svm_dev *sdev;
-
- rcu_read_lock();
- list_for_each_entry_rcu(sdev, &svm->devs, list) {
- info = dev_iommu_priv_get(sdev->dev);
-
- qi_flush_piotlb(sdev->iommu, sdev->did, svm->pasid, 0, -1UL, 0);
- if (info->ats_enabled) {
- qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid,
- svm->pasid, sdev->qdep,
- 0, 64 - VTD_PAGE_SHIFT);
- quirk_extra_dev_tlb_flush(info, 0, 64 - VTD_PAGE_SHIFT,
- svm->pasid, sdev->qdep);
- }
- }
- rcu_read_unlock();
-}
-
/* Pages have been freed at this point */
static void intel_arch_invalidate_secondary_tlbs(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start, unsigned long end)
{
struct intel_svm *svm = container_of(mn, struct intel_svm, notifier);
+ struct dmar_domain *domain = svm->domain;

if (start == 0 && end == -1UL) {
- intel_flush_svm_all(svm);
+ cache_tag_flush_all(domain);
return;
}

- intel_flush_svm_range(svm, start,
- (end - start + PAGE_SIZE - 1) >> VTD_PAGE_SHIFT, 0);
+ /*
+ * The mm_types defines vm_end as the first byte after the end address,
+ * different from IOMMU subsystem using the last address of an address
+ * range.
+ */
+ cache_tag_flush_range(domain, start, end - 1, 0);
}

static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
@@ -336,6 +273,7 @@ static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
INIT_LIST_HEAD_RCU(&svm->devs);

svm->notifier.ops = &intel_mmuops;
+ svm->domain = to_dmar_domain(domain);
ret = mmu_notifier_register(&svm->notifier, mm);
if (ret) {
kfree(svm);
@@ -801,6 +739,7 @@ struct iommu_domain *intel_svm_domain_alloc(void)
if (!domain)
return NULL;
domain->domain.ops = &intel_svm_domain_ops;
+ domain->use_first_level = true;
INIT_LIST_HEAD(&domain->cache_tags);
spin_lock_init(&domain->cache_lock);

--
2.34.1