[RFC PATCH 1/2] iommu: Add flags to sva_unbind()

Jean-Philippe Brucker
2020-10-15T09:03:05Z

Provide a way for device drivers to tell IOMMU drivers about the device
state and the cleanup work to be done, when unbinding. No functional
change.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
include/linux/intel-iommu.h | 2 +-
include/linux/iommu.h | 7 ++++---
drivers/iommu/intel/svm.c | 7 ++++---
drivers/iommu/iommu.c | 5 +++--
drivers/misc/uacce/uacce.c | 4 ++--
5 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index fbf5b3e7707e..5b66b23d591d 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -747,7 +747,7 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
int intel_svm_unbind_gpasid(struct device *dev, u32 pasid);
struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm,
void *drvdata);
-void intel_svm_unbind(struct iommu_sva *handle);
+void intel_svm_unbind(struct iommu_sva *handle, unsigned long flags);
u32 intel_svm_get_pasid(struct iommu_sva *handle);
int intel_svm_page_response(struct device *dev, struct iommu_fault_event *evt,
struct iommu_page_response *msg);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index b95a6f8db6ff..26c1358a2a37 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -285,7 +285,7 @@ struct iommu_ops {

struct iommu_sva *(*sva_bind)(struct device *dev, struct mm_struct *mm,
void *drvdata);
- void (*sva_unbind)(struct iommu_sva *handle);
+ void (*sva_unbind)(struct iommu_sva *handle, unsigned long flags);
u32 (*sva_get_pasid)(struct iommu_sva *handle);

int (*page_response)(struct device *dev,
@@ -636,7 +636,7 @@ int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev);
struct iommu_sva *iommu_sva_bind_device(struct device *dev,
struct mm_struct *mm,
void *drvdata);
-void iommu_sva_unbind_device(struct iommu_sva *handle);
+void iommu_sva_unbind_device(struct iommu_sva *handle, unsigned long flags);
u32 iommu_sva_get_pasid(struct iommu_sva *handle);

#else /* CONFIG_IOMMU_API */
@@ -1026,7 +1026,8 @@ iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata)
return NULL;
}

-static inline void iommu_sva_unbind_device(struct iommu_sva *handle)
+static inline void iommu_sva_unbind_device(struct iommu_sva *handle,
+ unsigned long flags)
{
}

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index f1861fa3d0e4..700b05612af9 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -651,7 +651,8 @@ intel_svm_bind_mm(struct device *dev, unsigned int flags,
}

/* Caller must hold pasid_mutex */
-static int intel_svm_unbind_mm(struct device *dev, u32 pasid)
+static int intel_svm_unbind_mm(struct device *dev, u32 pasid,
+ unsigned long flags)
{
struct intel_svm_dev *sdev;
struct intel_iommu *iommu;
@@ -1091,13 +1092,13 @@ intel_svm_bind(struct device *dev, struct mm_struct *mm, void *drvdata)
return sva;
}

-void intel_svm_unbind(struct iommu_sva *sva)
+void intel_svm_unbind(struct iommu_sva *sva, unsigned long flags)
{
struct intel_svm_dev *sdev;

mutex_lock(&pasid_mutex);
sdev = to_intel_svm_dev(sva);
- intel_svm_unbind_mm(sdev->dev, sdev->pasid);
+ intel_svm_unbind_mm(sdev->dev, sdev->pasid, flags);
mutex_unlock(&pasid_mutex);
}

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8c470f451a32..741c463095a8 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2991,6 +2991,7 @@ EXPORT_SYMBOL_GPL(iommu_sva_bind_device);
/**
* iommu_sva_unbind_device() - Remove a bond created with iommu_sva_bind_device
* @handle: the handle returned by iommu_sva_bind_device()
+ * @flags: IOMMU_UNBIND_* flags
*
* Put reference to a bond between device and address space. The device should
* not be issuing any more transaction for this PASID. All outstanding page
@@ -2998,7 +2999,7 @@ EXPORT_SYMBOL_GPL(iommu_sva_bind_device);
*
* Returns 0 on success, or an error value
*/
-void iommu_sva_unbind_device(struct iommu_sva *handle)
+void iommu_sva_unbind_device(struct iommu_sva *handle, unsigned long flags)
{
struct iommu_group *group;
struct device *dev = handle->dev;
@@ -3012,7 +3013,7 @@ void iommu_sva_unbind_device(struct iommu_sva *handle)
return;

mutex_lock(&group->mutex);
- ops->sva_unbind(handle);
+ ops->sva_unbind(handle, flags);
mutex_unlock(&group->mutex);

iommu_group_put(group);
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index 56dd98ab5a81..0800566a6656 100644
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -105,7 +105,7 @@ static int uacce_bind_queue(struct uacce_device *uacce, struct uacce_queue *q)

pasid = iommu_sva_get_pasid(handle);
if (pasid == IOMMU_PASID_INVALID) {
- iommu_sva_unbind_device(handle);
+ iommu_sva_unbind_device(handle, 0);
return -ENODEV;
}

@@ -118,7 +118,7 @@ static void uacce_unbind_queue(struct uacce_queue *q)
{
if (!q->handle)
return;
- iommu_sva_unbind_device(q->handle);
+ iommu_sva_unbind_device(q->handle, 0);
q->handle = NULL;
}

--
2.28.0