[PATCH v6 11/12] iommu/vt-d: Shared virtual address in scalable mode

Lu Baolu
2018-12-10T01:59:05Z

This patch enables the current SVA (Shared Virtual Address)
implementation to work in the scalable mode.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
---
drivers/iommu/intel-iommu.c | 38 ------------------------
drivers/iommu/intel-pasid.c | 2 +-
drivers/iommu/intel-pasid.h | 1 -
drivers/iommu/intel-svm.c | 58 ++++++++++++-------------------------
include/linux/intel-iommu.h | 9 +-----
5 files changed, 20 insertions(+), 88 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 21e5f1b9a2ca..4552166c553b 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5257,18 +5257,6 @@ static void intel_iommu_put_resv_regions(struct device *dev,
}

#ifdef CONFIG_INTEL_IOMMU_SVM
-static inline unsigned long intel_iommu_get_pts(struct device *dev)
-{
- int pts, max_pasid;
-
- max_pasid = intel_pasid_get_dev_max_id(dev);
- pts = find_first_bit((unsigned long *)&max_pasid, MAX_NR_PASID_BITS);
- if (pts < 5)
- return 0;
-
- return pts - 5;
-}
-
int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sdev)
{
struct device_domain_info *info;
@@ -5300,33 +5288,7 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sd
sdev->sid = PCI_DEVID(info->bus, info->devfn);

if (!(ctx_lo & CONTEXT_PASIDE)) {
- if (iommu->pasid_state_table)
- context[1].hi = (u64)virt_to_phys(iommu->pasid_state_table);
- context[1].lo = (u64)virt_to_phys(info->pasid_table->table) |
- intel_iommu_get_pts(sdev->dev);
-
- wmb();
- /* CONTEXT_TT_MULTI_LEVEL and CONTEXT_TT_DEV_IOTLB are both
- * extended to permit requests-with-PASID if the PASIDE bit
- * is set. which makes sense. For CONTEXT_TT_PASS_THROUGH,
- * however, the PASIDE bit is ignored and requests-with-PASID
- * are unconditionally blocked. Which makes less sense.
- * So convert from CONTEXT_TT_PASS_THROUGH to one of the new
- * "guest mode" translation types depending on whether ATS
- * is available or not. Annoyingly, we can't use the new
- * modes *unless* PASIDE is set. */
- if ((ctx_lo & CONTEXT_TT_MASK) == (CONTEXT_TT_PASS_THROUGH << 2)) {
- ctx_lo &= ~CONTEXT_TT_MASK;
- if (info->ats_supported)
- ctx_lo |= CONTEXT_TT_PT_PASID_DEV_IOTLB << 2;
- else
- ctx_lo |= CONTEXT_TT_PT_PASID << 2;
- }
ctx_lo |= CONTEXT_PASIDE;
- if (iommu->pasid_state_table)
- ctx_lo |= CONTEXT_DINVE;
- if (info->pri_supported)
- ctx_lo |= CONTEXT_PRS;
context[0].lo = ctx_lo;
wmb();
iommu->flush.flush_context(iommu, sdev->did, sdev->sid,
diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c
index c3dcf4dc2496..53fe5248d8f1 100644
--- a/drivers/iommu/intel-pasid.c
+++ b/drivers/iommu/intel-pasid.c
@@ -286,7 +286,7 @@ static inline void pasid_clear_entry(struct pasid_entry *pe)
WRITE_ONCE(pe->val[7], 0);
}

-void intel_pasid_clear_entry(struct device *dev, int pasid)
+static void intel_pasid_clear_entry(struct device *dev, int pasid)
{
struct pasid_entry *pe;

diff --git a/drivers/iommu/intel-pasid.h b/drivers/iommu/intel-pasid.h
index 512c63ec8a22..23537b3f34e3 100644
--- a/drivers/iommu/intel-pasid.h
+++ b/drivers/iommu/intel-pasid.h
@@ -58,7 +58,6 @@ void intel_pasid_free_table(struct device *dev);
struct pasid_table *intel_pasid_get_table(struct device *dev);
int intel_pasid_get_dev_max_id(struct device *dev);
struct pasid_entry *intel_pasid_get_entry(struct device *dev, int pasid);
-void intel_pasid_clear_entry(struct device *dev, int pasid);
int intel_pasid_setup_first_level(struct intel_iommu *iommu,
struct device *dev, pgd_t *pgd,
int pasid, u16 did, int flags);
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 9b6771a89207..935712ebda79 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -29,10 +29,6 @@

#include "intel-pasid.h"

-#define PASID_ENTRY_P BIT_ULL(0)
-#define PASID_ENTRY_FLPM_5LP BIT_ULL(9)
-#define PASID_ENTRY_SRE BIT_ULL(11)
-
static irqreturn_t prq_event_thread(int irq, void *d);

struct pasid_state_entry {
@@ -248,20 +244,6 @@ static void intel_invalidate_range(struct mmu_notifier *mn,
(end - start + PAGE_SIZE - 1) >> VTD_PAGE_SHIFT, 0, 0);
}

-
-static void intel_flush_pasid_dev(struct intel_svm *svm, struct intel_svm_dev *sdev, int pasid)
-{
- struct qi_desc desc;
-
- desc.qw0 = QI_PC_TYPE | QI_PC_DID(sdev->did) |
- QI_PC_PASID_SEL | QI_PC_PASID(pasid);
- desc.qw1 = 0;
- desc.qw2 = 0;
- desc.qw3 = 0;
-
- qi_submit_sync(&desc, svm->iommu);
-}
-
static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
{
struct intel_svm *svm = container_of(mn, struct intel_svm, notifier);
@@ -281,8 +263,7 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
*/
rcu_read_lock();
list_for_each_entry_rcu(sdev, &svm->devs, list) {
- intel_pasid_clear_entry(sdev->dev, svm->pasid);
- intel_flush_pasid_dev(svm, sdev, svm->pasid);
+ intel_pasid_tear_down_entry(svm->iommu, sdev->dev, svm->pasid);
intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, !svm->mm);
}
rcu_read_unlock();
@@ -301,11 +282,9 @@ static LIST_HEAD(global_svm_list);
int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ops *ops)
{
struct intel_iommu *iommu = intel_svm_device_to_iommu(dev);
- struct pasid_entry *entry;
struct intel_svm_dev *sdev;
struct intel_svm *svm = NULL;
struct mm_struct *mm = NULL;
- u64 pasid_entry_val;
int pasid_max;
int ret;

@@ -414,22 +393,22 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_
kfree(sdev);
goto out;
}
- pasid_entry_val = (u64)__pa(mm->pgd) | PASID_ENTRY_P;
- } else
- pasid_entry_val = (u64)__pa(init_mm.pgd) |
- PASID_ENTRY_P | PASID_ENTRY_SRE;
- if (cpu_feature_enabled(X86_FEATURE_LA57))
- pasid_entry_val |= PASID_ENTRY_FLPM_5LP;
-
- entry = intel_pasid_get_entry(dev, svm->pasid);
- WRITE_ONCE(entry->val[0], pasid_entry_val);
-
- /*
- * Flush PASID cache when a PASID table entry becomes
- * present.
- */
- if (cap_caching_mode(iommu->cap))
- intel_flush_pasid_dev(svm, sdev, svm->pasid);
+ }
+
+ spin_lock(&iommu->lock);
+ ret = intel_pasid_setup_first_level(iommu, dev,
+ mm ? mm->pgd : init_mm.pgd,
+ svm->pasid, FLPT_DEFAULT_DID,
+ mm ? 0 : PASID_FLAG_SUPERVISOR_MODE);
+ spin_unlock(&iommu->lock);
+ if (ret) {
+ if (mm)
+ mmu_notifier_unregister(&svm->notifier, mm);
+ intel_pasid_free_id(svm->pasid);
+ kfree(svm);
+ kfree(sdev);
+ goto out;
+ }

list_add_tail(&svm->list, &global_svm_list);
}
@@ -475,10 +454,9 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
* to use. We have a *shared* PASID table, because it's
* large and has to be physically contiguous. So it's
* hard to be as defensive as we might like. */
- intel_flush_pasid_dev(svm, sdev, svm->pasid);
+ intel_pasid_tear_down_entry(iommu, dev, svm->pasid);
intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, !svm->mm);
kfree_rcu(sdev, rcu);
- intel_pasid_clear_entry(dev, svm->pasid);

if (list_empty(&svm->devs)) {
intel_pasid_free_id(svm->pasid);
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 4ad62396e81e..cfcf9c1e1872 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -54,14 +54,7 @@
#define CONTEXT_TT_MULTI_LEVEL 0
#define CONTEXT_TT_DEV_IOTLB 1
#define CONTEXT_TT_PASS_THROUGH 2
-/* Extended context entry types */
-#define CONTEXT_TT_PT_PASID 4
-#define CONTEXT_TT_PT_PASID_DEV_IOTLB 5
-#define CONTEXT_TT_MASK (7ULL << 2)
-
-#define CONTEXT_DINVE (1ULL << 8)
-#define CONTEXT_PRS (1ULL << 9)
-#define CONTEXT_PASIDE (1ULL << 11)
+#define CONTEXT_PASIDE BIT_ULL(3)

/*
* Intel IOMMU register specification per version 1.0 public spec.
--
2.17.1