[PATCH 9/9] iommu/amd: Correctly encode huge pages in iommu page tables

From: Joerg Roedel
Date: Wed Apr 01 2015 - 09:00:43 EST


From: Joerg Roedel <jroedel@xxxxxxx>

When a default page-size for given level should be mapped,
the level encoding must be 0 rather than 7. This fixes an
issue seen on IOMMUv2 hardware, where this encoding is
enforced.

Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/iommu/amd_iommu.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 7a00e5d..aa710b0 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1390,13 +1390,14 @@ static int iommu_map_page(struct protection_domain *dom,
u64 __pte, *pte;
int i, count;

+ BUG_ON(!IS_ALIGNED(bus_addr, page_size));
+ BUG_ON(!IS_ALIGNED(phys_addr, page_size));
+
if (!(prot & IOMMU_PROT_MASK))
return -EINVAL;

- bus_addr = PAGE_ALIGN(bus_addr);
- phys_addr = PAGE_ALIGN(phys_addr);
- count = PAGE_SIZE_PTE_COUNT(page_size);
- pte = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);
+ count = PAGE_SIZE_PTE_COUNT(page_size);
+ pte = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);

if (!pte)
return -ENOMEM;
@@ -1405,7 +1406,7 @@ static int iommu_map_page(struct protection_domain *dom,
if (IOMMU_PTE_PRESENT(pte[i]))
return -EBUSY;

- if (page_size > PAGE_SIZE) {
+ if (count > 1) {
__pte = PAGE_SIZE_PTE(phys_addr, page_size);
__pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_P | IOMMU_PTE_FC;
} else
--
1.9.1

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