Merge tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[cascardo/linux.git] / drivers / iommu / iommu.c

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 02e4313..f7718d7 100644 (file)
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -737,7 +737,7 @@ static int add_iommu_group(struct device *dev, void *data)
        const struct iommu_ops *ops = cb->ops;
 
        if (!ops->add_device)
-               return -ENODEV;
+               return 0;
 
        WARN_ON(dev->iommu_group);
 
@@ -1143,14 +1143,24 @@ size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
 {
        struct scatterlist *s;
        size_t mapped = 0;
-       unsigned int i;
+       unsigned int i, min_pagesz;
        int ret;
 
-       for_each_sg(sg, s, nents, i) {
-               phys_addr_t phys = page_to_phys(sg_page(s));
+       if (unlikely(domain->ops->pgsize_bitmap == 0UL))
+               return 0;
 
-               /* We are mapping on page boundarys, so offset must be 0 */
-               if (s->offset)
+       min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+
+       for_each_sg(sg, s, nents, i) {
+               phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
+
+               /*
+                * We are mapping on IOMMU page boundaries, so offset within
+                * the page must be 0. However, the IOMMU may support pages
+                * smaller than PAGE_SIZE, so s->offset may still represent
+                * an offset of that boundary within the CPU page.
+                */
+               if (!IS_ALIGNED(s->offset, min_pagesz))
                        goto out_err;
 
                ret = iommu_map(domain, iova + mapped, phys, s->length, prot);