From: Joerg Roedel <jroe...@suse.de>
The IOMMU core code has support for deferring the attachment of a domain
to a device. This is needed in kdump kernels where the new domain must
not be attached to a device before the device driver takes it over.
But this needs support from the dma-ops code too, to actually do the
late attachment when there are DMA-API calls for the device. This got
lost in the AMD IOMMU driver after converting it to the dma-iommu code.
Do the late attachment in the dma-iommu code-path to fix the issue.
Cc: Jerry Snitselaar <jsnit...@redhat.com>
Cc: Tom Murphy <murph...@tcd.ie>
Reported-by: Jerry Snitselaar <jsnit...@redhat.com>
Tested-by: Jerry Snitselaar <jsnit...@redhat.com>
Fixes: be62dbf554c5 ("iommu/amd: Convert AMD iommu driver to the dma-iommu api")
Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
drivers/iommu/iommu.c | 33 +++++++++++++++++++++++++++------
1 file changed, 27 insertions(+), 6 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 4050569188be..f54ebb964271 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1889,13 +1889,19 @@ void iommu_domain_free(struct iommu_domain *domain)
}
EXPORT_SYMBOL_GPL(iommu_domain_free);
-static int __iommu_attach_device(struct iommu_domain *domain,
- struct device *dev)
+static bool __iommu_is_attach_deferred(struct iommu_domain *domain,
+ struct device *dev)
+{
+ if (!domain->ops->is_attach_deferred)
+ return false;
+
+ return domain->ops->is_attach_deferred(domain, dev);
+}
+
+static int __iommu_attach_device_no_defer(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;
@@ -1903,9 +1909,19 @@ static int __iommu_attach_device(struct iommu_domain
*domain,
ret = domain->ops->attach_dev(domain, dev);
if (!ret)
trace_attach_device_to_domain(dev);
+
return ret;
}
+static int __iommu_attach_device(struct iommu_domain *domain,
+ struct device *dev)
+{
+ if (__iommu_is_attach_deferred(domain, dev))
+ return 0;
+
+ return __iommu_attach_device_no_defer(domain, dev);
+}
+
int iommu_attach_device(struct iommu_domain *domain, struct device *dev)
{
struct iommu_group *group;
@@ -2023,7 +2039,12 @@ EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
*/
struct iommu_domain *iommu_get_dma_domain(struct device *dev)
{
- return dev->iommu_group->default_domain;
+ struct iommu_domain *domain = dev->iommu_group->default_domain;
+
+ if (__iommu_is_attach_deferred(domain, dev))
+ __iommu_attach_device_no_defer(domain, dev);
+
+ return domain;
}
/*
--
2.25.1
