[PATCH 3.2 119/125] iommu/vt-d: Fix missing IOTLB flush in intel_iommu_unmap()

Ben Hutchings
2014-07-08T19:24:33Z

From: David Woodhouse <dwmw2@infradead.org>

Part of commit ea8ea460c9ace60bbb5ac6e5521d637d5c15293d upstream.

This missing IOTLB flush was added as a minor, inconsequential bug-fix
in commit ea8ea460c ("iommu/vt-d: Clean up and fix page table clear/free
behaviour") in 3.15. It wasn't originally intended for -stable but a
couple of users have reported issues which turn out to be fixed by
adding the missing flush.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
[bwh: Backported to 3.2:
- Adjust context
- Use &dmar_domain->iommu_bmp, as it is a single word not an array]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/iommu/intel-iommu.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)

--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4070,7 +4070,7 @@ static int intel_iommu_unmap(struct iomm
{
struct dmar_domain *dmar_domain = domain->priv;
size_t size = PAGE_SIZE << gfp_order;
- int order;
+ int order, iommu_id;

order = dma_pte_clear_range(dmar_domain, iova >> VTD_PAGE_SHIFT,
(iova + size - 1) >> VTD_PAGE_SHIFT);
@@ -4078,6 +4078,22 @@ static int intel_iommu_unmap(struct iomm
if (dmar_domain->max_addr == iova + size)
dmar_domain->max_addr = iova;

+ for_each_set_bit(iommu_id, &dmar_domain->iommu_bmp, g_num_of_iommus) {
+ struct intel_iommu *iommu = g_iommus[iommu_id];
+ int num, ndomains;
+
+ /*
+ * find bit position of dmar_domain
+ */
+ ndomains = cap_ndoms(iommu->cap);
+ for_each_set_bit(num, iommu->domain_ids, ndomains) {
+ if (iommu->domains[num] == dmar_domain)
+ iommu_flush_iotlb_psi(iommu, num,
+ iova >> VTD_PAGE_SHIFT,
+ 1 << order, 0);
+ }
+ }
+
return order;
}