[10/31] powerpc/iommu: 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/powerpc/kernel/iommu.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

Patch

diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index a8e3490..0f52e40 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -457,7 +457,7 @@  int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
 
 	max_seg_size = dma_get_max_seg_size(dev);
 	for_each_sg(sglist, s, nelems, i) {
-		unsigned long vaddr, npages, entry, slen;
+		unsigned long paddr, npages, entry, slen;
 
 		slen = s->length;
 		/* Sanity check */
@@ -466,22 +466,22 @@  int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
 			continue;
 		}
 		/* Allocate iommu entries for that segment */
-		vaddr = (unsigned long) sg_virt(s);
-		npages = iommu_num_pages(vaddr, slen, IOMMU_PAGE_SIZE(tbl));
+		paddr = sg_phys(s);
+		npages = iommu_num_pages(paddr, slen, IOMMU_PAGE_SIZE(tbl));
 		align = 0;
 		if (tbl->it_page_shift < PAGE_SHIFT && slen >= PAGE_SIZE &&
-		    (vaddr & ~PAGE_MASK) == 0)
+		    (paddr & ~PAGE_MASK) == 0)
 			align = PAGE_SHIFT - tbl->it_page_shift;
 		entry = iommu_range_alloc(dev, tbl, npages, &handle,
 					  mask >> tbl->it_page_shift, align);
 
-		DBG("  - vaddr: %lx, size: %lx\n", vaddr, slen);
+		DBG("  - paddr: %lx, size: %lx\n", paddr, slen);
 
 		/* Handle failure */
 		if (unlikely(entry == DMA_ERROR_CODE)) {
 			if (printk_ratelimit())
 				dev_info(dev, "iommu_alloc failed, tbl %p "
-					 "vaddr %lx npages %lu\n", tbl, vaddr,
+					 "paddr %lx npages %lu\n", tbl, paddr,
 					 npages);
 			goto failure;
 		}
@@ -496,7 +496,7 @@  int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
 
 		/* Insert into HW table */
 		build_fail = tbl->it_ops->set(tbl, entry, npages,
-					      vaddr & IOMMU_PAGE_MASK(tbl),
+					      paddr & IOMMU_PAGE_MASK(tbl),
 					      direction, attrs);
 		if(unlikely(build_fail))
 			goto failure;