[05/31] x86/pci-calgary: handle page-less SG entries

Commit Message

Christoph Hellwig Aug. 12, 2015, 7:05 a.m. UTC

For the iommu offset we just need and offset into the page.  Calculate
that using the physical address instead of using the virtual address
so that we don't require a virtual mapping.

Signed-off-by: Christoph Hellwig <[e-mail]>
---
 arch/x86/kernel/pci-calgary_64.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

Patch

diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c
index 0497f71..8f1581d 100644
--- a/arch/x86/kernel/pci-calgary_64.c
+++ b/arch/x86/kernel/pci-calgary_64.c
@@ -368,16 +368,14 @@  static int calgary_map_sg(struct device *dev, struct scatterlist *sg,
 {
 	struct iommu_table *tbl = find_iommu_table(dev);
 	struct scatterlist *s;
-	unsigned long vaddr;
+	unsigned long paddr;
 	unsigned int npages;
 	unsigned long entry;
 	int i;
 
 	for_each_sg(sg, s, nelems, i) {
-		BUG_ON(!sg_page(s));
-
-		vaddr = (unsigned long) sg_virt(s);
-		npages = iommu_num_pages(vaddr, s->length, PAGE_SIZE);
+		paddr = sg_phys(s);
+		npages = iommu_num_pages(paddr, s->length, PAGE_SIZE);
 
 		entry = iommu_range_alloc(dev, tbl, npages);
 		if (entry == DMA_ERROR_CODE) {
@@ -389,7 +387,7 @@  static int calgary_map_sg(struct device *dev, struct scatterlist *sg,
 		s->dma_address = (entry << PAGE_SHIFT) | s->offset;
 
 		/* insert into HW table */
-		tce_build(tbl, entry, npages, vaddr & PAGE_MASK, dir);
+		tce_build(tbl, entry, npages, paddr & PAGE_MASK, dir);
 
 		s->dma_length = s->length;
 	}