[PATCH 3/8] iommu: Add generic_device_group() function

[Joerg Roedel <joro@8bytes.org>]

From: Joerg Roedel <jroedel@suse.de>

This function can be used as a device_group call-back and
just allocates one iommu-group per device.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/iommu.c | 15 +++++++++++++++
 include/linux/iommu.h |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index fdea700..a80c9c5 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -728,6 +728,21 @@ static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
 }
 
 /*
+ * Generic device_group call-back function. It just allocates one
+ * iommu-group per device.
+ */
+struct iommu_group *generic_device_group(struct device *dev)
+{
+	struct iommu_group *group;
+
+	group = iommu_group_alloc();
+	if (IS_ERR(group))
+		return NULL;
+
+	return group;
+}
+
+/*
  * Use standard PCI bus topology, isolation features, and DMA alias quirks
  * to find or create an IOMMU group for a device.
  */
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 8026e6a..c73824f 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -318,6 +318,8 @@ static inline size_t iommu_map_sg(struct iommu_domain *domain,
 
 /* PCI device grouping function */
 extern struct iommu_group *pci_device_group(struct device *dev);
+/* Generic device grouping function */
+extern struct iommu_group *generic_device_group(struct device *dev);
 
 #else /* CONFIG_IOMMU_API */
 
-- 
1.9.1