[PATCH v5 5/9] iommu/vt-d: Flush PASID-based iotlb for iova over first level

Lu Baolu
2019-12-24T07:47:01Z

When software has changed first-level tables, it should invalidate
the affected IOTLB and the paging-structure-caches using the PASID-
based-IOTLB Invalidate Descriptor defined in spec 6.5.2.4.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/dmar.c | 41 +++++++++++++++++++++++++++
drivers/iommu/intel-iommu.c | 56 +++++++++++++++++++++++++++----------
include/linux/intel-iommu.h | 2 ++
3 files changed, 84 insertions(+), 15 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 3acfa6a25fa2..fb30d5053664 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1371,6 +1371,47 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
qi_submit_sync(&desc, iommu);
}

+/* PASID-based IOTLB invalidation */
+void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u32 pasid, u64 addr,
+ unsigned long npages, bool ih)
+{
+ struct qi_desc desc = {.qw2 = 0, .qw3 = 0};
+
+ /*
+ * npages == -1 means a PASID-selective invalidation, otherwise,
+ * a positive value for Page-selective-within-PASID invalidation.
+ * 0 is not a valid input.
+ */
+ if (WARN_ON(!npages)) {
+ pr_err("Invalid input npages = %ld\n", npages);
+ return;
+ }
+
+ if (npages == -1) {
+ desc.qw0 = QI_EIOTLB_PASID(pasid) |
+ QI_EIOTLB_DID(did) |
+ QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) |
+ QI_EIOTLB_TYPE;
+ desc.qw1 = 0;
+ } else {
+ int mask = ilog2(__roundup_pow_of_two(npages));
+ unsigned long align = (1ULL << (VTD_PAGE_SHIFT + mask));
+
+ if (WARN_ON_ONCE(!ALIGN(addr, align)))
+ addr &= ~(align - 1);
+
+ desc.qw0 = QI_EIOTLB_PASID(pasid) |
+ QI_EIOTLB_DID(did) |
+ QI_EIOTLB_GRAN(QI_GRAN_PSI_PASID) |
+ QI_EIOTLB_TYPE;
+ desc.qw1 = QI_EIOTLB_ADDR(addr) |
+ QI_EIOTLB_IH(ih) |
+ QI_EIOTLB_AM(mask);
+ }
+
+ qi_submit_sync(&desc, iommu);
+}
+
/*
* Disable Queued Invalidation interface.
*/
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 071cbc172ce8..54db6bc0b281 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -1509,6 +1509,20 @@ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
spin_unlock_irqrestore(&device_domain_lock, flags);
}

+static void domain_flush_piotlb(struct intel_iommu *iommu,
+ struct dmar_domain *domain,
+ u64 addr, unsigned long npages, bool ih)
+{
+ u16 did = domain->iommu_did[iommu->seq_id];
+
+ if (domain->default_pasid)
+ qi_flush_piotlb(iommu, did, domain->default_pasid,
+ addr, npages, ih);
+
+ if (!list_empty(&domain->devices))
+ qi_flush_piotlb(iommu, did, PASID_RID2PASID, addr, npages, ih);
+}
+
static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
struct dmar_domain *domain,
unsigned long pfn, unsigned int pages,
@@ -1522,18 +1536,23 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,

if (ih)
ih = 1 << 6;
- /*
- * Fallback to domain selective flush if no PSI support or the size is
- * too big.
- * PSI requires page size to be 2 ^ x, and the base address is naturally
- * aligned to the size
- */
- if (!cap_pgsel_inv(iommu->cap) || mask > cap_max_amask_val(iommu->cap))
- iommu->flush.flush_iotlb(iommu, did, 0, 0,
- DMA_TLB_DSI_FLUSH);
- else
- iommu->flush.flush_iotlb(iommu, did, addr | ih, mask,
- DMA_TLB_PSI_FLUSH);
+
+ if (domain_use_first_level(domain)) {
+ domain_flush_piotlb(iommu, domain, addr, pages, ih);
+ } else {
+ /*
+ * Fallback to domain selective flush if no PSI support or
+ * the size is too big. PSI requires page size to be 2 ^ x,
+ * and the base address is naturally aligned to the size.
+ */
+ if (!cap_pgsel_inv(iommu->cap) ||
+ mask > cap_max_amask_val(iommu->cap))
+ iommu->flush.flush_iotlb(iommu, did, 0, 0,
+ DMA_TLB_DSI_FLUSH);
+ else
+ iommu->flush.flush_iotlb(iommu, did, addr | ih, mask,
+ DMA_TLB_PSI_FLUSH);
+ }

/*
* In caching mode, changes of pages from non-present to present require
@@ -1548,8 +1567,11 @@ static inline void __mapping_notify_one(struct intel_iommu *iommu,
struct dmar_domain *domain,
unsigned long pfn, unsigned int pages)
{
- /* It's a non-present to present mapping. Only flush if caching mode */
- if (cap_caching_mode(iommu->cap))
+ /*
+ * It's a non-present to present mapping. Only flush if caching mode
+ * and second level.
+ */
+ if (cap_caching_mode(iommu->cap) && !domain_use_first_level(domain))
iommu_flush_iotlb_psi(iommu, domain, pfn, pages, 0, 1);
else
iommu_flush_write_buffer(iommu);
@@ -1566,7 +1588,11 @@ static void iommu_flush_iova(struct iova_domain *iovad)
struct intel_iommu *iommu = g_iommus[idx];
u16 did = domain->iommu_did[iommu->seq_id];

- iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
+ if (domain_use_first_level(domain))
+ domain_flush_piotlb(iommu, domain, 0, -1, 0);
+ else
+ iommu->flush.flush_iotlb(iommu, did, 0, 0,
+ DMA_TLB_DSI_FLUSH);

if (!cap_caching_mode(iommu->cap))
iommu_flush_dev_iotlb(get_iommu_domain(iommu, did),
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 454c69712131..3a4708a8a414 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -650,6 +650,8 @@ extern void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
unsigned int size_order, u64 type);
extern void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
u16 qdep, u64 addr, unsigned mask);
+void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u32 pasid, u64 addr,
+ unsigned long npages, bool ih);
extern int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu);

extern int dmar_ir_support(void);
--
2.17.1