[PATCH] iommu: Always define struct iommu_fwspec

[Thierry Reding]

From: Thierry Reding <treding@xxxxxxxxxx>

In order to fully make use of the !IOMMU_API stub functions, make the
struct iommu_fwspec always available so that users of the stubs can keep
using the structure's internals without causing compile failures.

Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Hi Joerg,

this is a rebased patch extracted from an ancient series that never
ended up getting applied:

	https://lore.kernel.org/all/20191209120005.2254786-3-thierry.reding@xxxxxxxxx/

You had already acked this particular patch, so maybe you can pick this
up. I've seen at least two discussions where this was brought up again,
so I figured it'd be worth sending this out again because it can help
remove a number of #ifdef blocks throughout the kernel.

 include/linux/iommu.h | 39 +++++++++++++++++++--------------------
 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index a325532aeab5..e3295c45d18f 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -173,6 +173,25 @@ enum iommu_dev_features {
 
 #define IOMMU_PASID_INVALID	(-1U)
 
+/**
+ * struct iommu_fwspec - per-device IOMMU instance data
+ * @ops: ops for this device's IOMMU
+ * @iommu_fwnode: firmware handle for this device's IOMMU
+ * @flags: IOMMU_FWSPEC_* flags
+ * @num_ids: number of associated device IDs
+ * @ids: IDs which this device may present to the IOMMU
+ */
+struct iommu_fwspec {
+	const struct iommu_ops	*ops;
+	struct fwnode_handle	*iommu_fwnode;
+	u32			flags;
+	unsigned int		num_ids;
+	u32			ids[];
+};
+
+/* ATS is supported */
+#define IOMMU_FWSPEC_PCI_RC_ATS			(1 << 0)
+
 #ifdef CONFIG_IOMMU_API
 
 /**
@@ -598,25 +617,6 @@ extern struct iommu_group *generic_device_group(struct device *dev);
 /* FSL-MC device grouping function */
 struct iommu_group *fsl_mc_device_group(struct device *dev);
 
-/**
- * struct iommu_fwspec - per-device IOMMU instance data
- * @ops: ops for this device's IOMMU
- * @iommu_fwnode: firmware handle for this device's IOMMU
- * @flags: IOMMU_FWSPEC_* flags
- * @num_ids: number of associated device IDs
- * @ids: IDs which this device may present to the IOMMU
- */
-struct iommu_fwspec {
-	const struct iommu_ops	*ops;
-	struct fwnode_handle	*iommu_fwnode;
-	u32			flags;
-	unsigned int		num_ids;
-	u32			ids[];
-};
-
-/* ATS is supported */
-#define IOMMU_FWSPEC_PCI_RC_ATS			(1 << 0)
-
 /**
  * struct iommu_sva - handle to a device-mm bond
  */
@@ -680,7 +680,6 @@ bool iommu_group_dma_owner_claimed(struct iommu_group *group);
 
 struct iommu_ops {};
 struct iommu_group {};
-struct iommu_fwspec {};
 struct iommu_device {};
 struct iommu_fault_param {};
 struct iommu_iotlb_gather {};
-- 
2.37.3