[PATCH 3.12 100/111] iommu/amd: Optimize amd_iommu_iova_to_phys for new fetch_pte interface

From: Jiri Slaby
Date: Wed Jun 10 2015 - 11:39:46 EST


From: Joerg Roedel <jroedel@xxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit b24b1b63a37d05d61601d643ef30f95dd2452048 upstream.

Now that fetch_pte returns the page-size of the pte, this
function can be optimized too.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/iommu/amd_iommu.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 9e91d8c38a1e..db84a3c1254a 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3432,7 +3432,6 @@ static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
{
struct protection_domain *domain = dom->priv;
unsigned long offset_mask, pte_pgsize;
- phys_addr_t paddr;
u64 *pte, __pte;

if (domain->mode == PAGE_MODE_NONE)
@@ -3443,15 +3442,10 @@ static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
if (!pte || !IOMMU_PTE_PRESENT(*pte))
return 0;

- if (PM_PTE_LEVEL(*pte) == 0)
- offset_mask = PAGE_SIZE - 1;
- else
- offset_mask = PTE_PAGE_SIZE(*pte) - 1;
-
- __pte = *pte & PM_ADDR_MASK;
- paddr = (__pte & ~offset_mask) | (iova & offset_mask);
+ offset_mask = pte_pgsize - 1;
+ __pte = *pte & PM_ADDR_MASK;

- return paddr;
+ return (__pte & ~offset_mask) | (iova & offset_mask);
}

static int amd_iommu_domain_has_cap(struct iommu_domain *domain,
--
2.4.2

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