x86_64: abstract how we find the iommu_table for a device

... in preparation for doing it differently for CalIOC2.

Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 14 insertions, 7 deletions

diff --git a/arch/x86_64/kernel/pci-calgary.c b/arch/x86_64/kernel/pci-calgary.c
index 7218b5b51e08..a2828e156c3d 100644
--- a/arch/x86_64/kernel/pci-calgary.c
+++ b/arch/x86_64/kernel/pci-calgary.c
@@ -344,6 +344,15 @@ static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
         spin_unlock_irqrestore(&tbl->it_lock, flags);
 }
 
+static inline struct iommu_table *find_iommu_table(struct device *dev)
+{
+        struct iommu_table *tbl;
+
+        tbl = to_pci_dev(dev)->bus->self->sysdata;
+
+        return tbl;
+}
+
 static void __calgary_unmap_sg(struct iommu_table *tbl,
         struct scatterlist *sglist, int nelems, int direction)
 {
@@ -365,7 +374,7 @@ void calgary_unmap_sg(struct device *dev, struct scatterlist *sglist,
                       int nelems, int direction)
 {
         unsigned long flags;
-        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        struct iommu_table *tbl = find_iommu_table(dev);
 
         if (!translate_phb(to_pci_dev(dev)))
                 return;
@@ -394,7 +403,7 @@ static int calgary_nontranslate_map_sg(struct device* dev,
 int calgary_map_sg(struct device *dev, struct scatterlist *sg,
         int nelems, int direction)
 {
-        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        struct iommu_table *tbl = find_iommu_table(dev);
         unsigned long flags;
         unsigned long vaddr;
         unsigned int npages;
@@ -448,7 +457,7 @@ dma_addr_t calgary_map_single(struct device *dev, void *vaddr,
         dma_addr_t dma_handle = bad_dma_address;
         unsigned long uaddr;
         unsigned int npages;
-        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        struct iommu_table *tbl = find_iommu_table(dev);
 
         uaddr = (unsigned long)vaddr;
         npages = num_dma_pages(uaddr, size);
@@ -464,7 +473,7 @@ dma_addr_t calgary_map_single(struct device *dev, void *vaddr,
 void calgary_unmap_single(struct device *dev, dma_addr_t dma_handle,
         size_t size, int direction)
 {
-        struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
+        struct iommu_table *tbl = find_iommu_table(dev);
         unsigned int npages;
 
         if (!translate_phb(to_pci_dev(dev)))
@@ -480,9 +489,7 @@ void* calgary_alloc_coherent(struct device *dev, size_t size,
         void *ret = NULL;
         dma_addr_t mapping;
         unsigned int npages, order;
-        struct iommu_table *tbl;
-
-        tbl = to_pci_dev(dev)->bus->self->sysdata;
+        struct iommu_table *tbl = find_iommu_table(dev);
 
         size = PAGE_ALIGN(size); /* size rounded up to full pages */
         npages = size >> PAGE_SHIFT;