[PATCH 9/9] x86/iommu: use dma_ops_list in get_dma_ops

[Joerg Roedel <joerg.roedel@amd.com>]

This patch enables stackable dma_ops on x86. To do this, it also enables
the per-device dma_ops on i386.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kernel/pci-dma.c     |   26 ++++++++++++++++++++++++++
 include/asm-x86/device.h      |    6 +++---
 include/asm-x86/dma-mapping.h |   14 +++++++-------
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index b990fb6..2e517c2 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -82,6 +82,32 @@ void x86_register_dma_ops(struct dma_mapping_ops *ops,
 	write_unlock_irqrestore(&dma_ops_list_lock, flags);
 }
 
+struct dma_mapping_ops *find_dma_ops_for_device(struct device *dev)
+{
+	int i;
+	unsigned long flags;
+	struct dma_mapping_ops *entry, *ops = NULL;
+
+	read_lock_irqsave(&dma_ops_list_lock, flags);
+
+	for (i = 0; i < DMA_OPS_TYPE_MAX; ++i)
+		list_for_each_entry(entry, &dma_ops_list[i], list) {
+			if (!entry->device_supported)
+				continue;
+			if (entry->device_supported(dev)) {
+				ops = entry;
+				goto out;
+			}
+		}
+out:
+	read_unlock_irqrestore(&dma_ops_list_lock, flags);
+
+	BUG_ON(ops == NULL);
+
+	return ops;
+}
+EXPORT_SYMBOL(find_dma_ops_for_device);
+
 int dma_set_mask(struct device *dev, u64 mask)
 {
 	if (!dev->dma_mask || !dma_supported(dev, mask))
diff --git a/include/asm-x86/device.h b/include/asm-x86/device.h
index 3c034f4..9ed12e3 100644
--- a/include/asm-x86/device.h
+++ b/include/asm-x86/device.h
@@ -5,9 +5,9 @@ struct dev_archdata {
 #ifdef CONFIG_ACPI
 	void	*acpi_handle;
 #endif
-#ifdef CONFIG_X86_64
-struct dma_mapping_ops *dma_ops;
-#endif
+
+	struct dma_mapping_ops *dma_ops;
+
 #ifdef CONFIG_DMAR
 	void *iommu; /* hook for IOMMU specific extension */
 #endif
diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
index 128786b..83d6d7f 100644
--- a/include/asm-x86/dma-mapping.h
+++ b/include/asm-x86/dma-mapping.h
@@ -82,19 +82,19 @@ enum dma_ops_driver_type {
 
 extern void x86_register_dma_ops(struct dma_mapping_ops *ops,
 				 enum dma_ops_driver_type type);
+extern struct dma_mapping_ops *find_dma_ops_for_device(struct device *dev);
 
 extern struct dma_mapping_ops *dma_ops;
 
 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
 {
-#ifdef CONFIG_X86_32
-	return dma_ops;
-#else
-	if (unlikely(!dev) || !dev->archdata.dma_ops)
+	if (unlikely(!dev))
 		return dma_ops;
-	else
-		return dev->archdata.dma_ops;
-#endif
+
+	if (unlikely(!dev->archdata.dma_ops))
+		dev->archdata.dma_ops = find_dma_ops_for_device(dev);
+
+	return dev->archdata.dma_ops;
 }
 
 /* Make sure we keep the same behaviour */
-- 
1.5.6.4