[PATCH v9 08/13] iommu: Add is_attach_deferred call-back to iommu-ops

Baoquan He
2017-08-01T11:39:29Z

This new call-back will be used to check if the domain attach need be
deferred for now. If yes, the domain attach/detach will return directly.

Signed-off-by: Baoquan He <bhe@redhat.com>
---
drivers/iommu/iommu.c | 8 ++++++++
include/linux/iommu.h | 1 +
2 files changed, 9 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3f6ea160afed..86581b115b92 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1283,6 +1283,10 @@ static int __iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
int ret;
+ if ((domain->ops->is_attach_deferred != NULL) &&
+ domain->ops->is_attach_deferred(domain, dev))
+ return 0;
+
if (unlikely(domain->ops->attach_dev == NULL))
return -ENODEV;

@@ -1324,6 +1328,10 @@ EXPORT_SYMBOL_GPL(iommu_attach_device);
static void __iommu_detach_device(struct iommu_domain *domain,
struct device *dev)
{
+ if ((domain->ops->is_attach_deferred != NULL) &&
+ domain->ops->is_attach_deferred(domain, dev))
+ return;
+
if (unlikely(domain->ops->detach_dev == NULL))
return;

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 2cb54adc4a33..63983c9e6c3a 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -225,6 +225,7 @@ struct iommu_ops {
u32 (*domain_get_windows)(struct iommu_domain *domain);

int (*of_xlate)(struct device *dev, struct of_phandle_args *args);
+ bool (*is_attach_deferred)(struct iommu_domain *domain, struct device *dev);

unsigned long pgsize_bitmap;
};
--
2.5.5