This patch adds a new "flush" callback to iommu_ops, which is supposed
to perform any necessary flushes within given IOMMU domain to make any
changes to mappings of given area [iova; iova + size) be reflected to
IOMMU clients.
The purpose is to let IOMMU drivers skip page-by-page flushes and
replace it with one flush of full address range on devices which support
it.
Signed-off-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
---
drivers/iommu/iommu.c | 33 ++++++++++++++++++++++++++++++---
include/linux/iommu.h | 2 ++
2 files changed, 32 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 049df49..d6bb8fe 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1286,8 +1286,15 @@ static size_t iommu_pgsize(struct iommu_domain *domain,
return pgsize;
}
-int iommu_map(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t paddr, size_t size, int prot)
+static void iommu_flush(struct iommu_domain *domain, unsigned long iova,
+ size_t size)
+{
+ if (domain->ops->flush)
+ domain->ops->flush(domain, iova, size);
+}
+
+static int __iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
{
unsigned long orig_iova = iova;
unsigned int min_pagesz;
@@ -1340,6 +1347,20 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
return ret;
}
+
+int iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ int ret;
+
+ ret = __iommu_map(domain, iova, paddr, size, prot);
+ if (ret)
+ return ret;
+
+ iommu_flush(domain, iova, size);
+
+ return 0;
+}
EXPORT_SYMBOL_GPL(iommu_map);
size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
@@ -1389,6 +1410,7 @@ size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
unmapped += unmapped_page;
}
+ iommu_flush(domain, orig_iova, unmapped);
trace_unmap(orig_iova, size, unmapped);
return unmapped;
}
@@ -1419,19 +1441,24 @@ size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
if (!IS_ALIGNED(s->offset, min_pagesz))
goto out_err;
- ret = iommu_map(domain, iova + mapped, phys, s->length, prot);
+ ret = __iommu_map(domain, iova + mapped, phys, s->length, prot);
if (ret)
goto out_err;
mapped += s->length;
}
+ iommu_flush(domain, iova, mapped);
+
return mapped;
out_err:
/* undo mappings already done */
iommu_unmap(domain, iova, mapped);
+ /* flush in case part of our mapping already got cached */
+ iommu_flush(domain, iova, mapped);
+
return 0;
}
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index f9c1b6d..18e59a9 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -164,6 +164,8 @@ struct iommu_ops {
size_t size);
size_t (*map_sg)(struct iommu_domain *domain, unsigned long iova,
struct scatterlist *sg, unsigned int nents, int prot);
+ void (*flush)(struct iommu_domain *domain, unsigned long iova,
+ size_t size);
phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
int (*add_device)(struct device *dev);
void (*remove_device)(struct device *dev);
--
2.6.0.rc2.230.g3dd15c0
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