[PATCH v2] iommu/amd: flush not present cache in iommu_map_page

From: Tom Murphy
Date: Sun Apr 28 2019 - 19:47:58 EST


check if there is a not-present cache present and flush it if there is.

Signed-off-by: Tom Murphy <tmurphy@xxxxxxxxxx>
---
drivers/iommu/amd_iommu.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index f7cdd2ab7f11..ebd062522cf5 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1307,6 +1307,16 @@ static void domain_flush_complete(struct protection_domain *domain)
}
}

+/* Flush the not present cache if it exists */
+static void domain_flush_np_cache(struct protection_domain *domain,
+ dma_addr_t iova, size_t size)
+{
+ if (unlikely(amd_iommu_np_cache)) {
+ domain_flush_pages(domain, iova, size);
+ domain_flush_complete(domain);
+ }
+}
+

/*
* This function flushes the DTEs for all devices in domain
@@ -2435,10 +2445,7 @@ static dma_addr_t __map_single(struct device *dev,
}
address += offset;

- if (unlikely(amd_iommu_np_cache)) {
- domain_flush_pages(&dma_dom->domain, address, size);
- domain_flush_complete(&dma_dom->domain);
- }
+ domain_flush_np_cache(&dma_dom->domain, address, size);

out:
return address;
@@ -2617,6 +2624,8 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
s->dma_length = s->length;
}

+ domain_flush_np_cache(domain, s->dma_address, s->dma_length);
+
return nelems;

out_unmap:
@@ -3101,6 +3110,8 @@ static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
ret = iommu_map_page(domain, iova, paddr, page_size, prot, GFP_KERNEL);
mutex_unlock(&domain->api_lock);

+ domain_flush_np_cache(domain, iova, page_size);
+
return ret;
}

--
2.17.1