Up until now PAGE_SIZE was always a multiple of iovad->granule
such that adjacent pages were never exposed to untrusted devices
due to allocations done as part of the coherent DMA API.
With PAGE_SIZE < iovad->granule however all these allocations
must also be aligned to iovad->granule.
Signed-off-by: Sven Peter <s...@svenpeter.dev>
---
drivers/iommu/dma-iommu.c | 40 ++++++++++++++++++++++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index d0bc8c06e1a4..e8eae34e9e4f 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -735,10 +735,16 @@ static void *iommu_dma_alloc_remap(struct device *dev,
size_t size,
dma_addr_t *dma_handle, gfp_t gfp, pgprot_t prot,
unsigned long attrs)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
struct page **pages;
struct sg_table sgt;
void *vaddr;
+ if (dev_is_untrusted(dev))
+ size = iova_align(iovad, size);
+
pages = __iommu_dma_alloc_noncontiguous(dev, size, &sgt, gfp, prot,
attrs);
if (!pages)
@@ -762,12 +768,18 @@ static struct sg_table
*iommu_dma_alloc_noncontiguous(struct device *dev,
size_t size, enum dma_data_direction dir, gfp_t gfp,
unsigned long attrs)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
struct dma_sgt_handle *sh;
sh = kmalloc(sizeof(*sh), gfp);
if (!sh)
return NULL;
+ if (dev_is_untrusted(dev))
+ size = iova_align(iovad, size);
+
sh->pages = __iommu_dma_alloc_noncontiguous(dev, size, &sh->sgt, gfp,
PAGE_KERNEL, attrs);
if (!sh->pages) {
@@ -780,8 +792,15 @@ static struct sg_table
*iommu_dma_alloc_noncontiguous(struct device *dev,
static void iommu_dma_free_noncontiguous(struct device *dev, size_t size,
struct sg_table *sgt, enum dma_data_direction dir)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
struct dma_sgt_handle *sh = sgt_handle(sgt);
+
+ if (dev_is_untrusted(dev))
+ size = iova_align(iovad, size);
+
__iommu_dma_unmap(dev, sgt->sgl->dma_address, size);
__iommu_dma_free_pages(sh->pages, PAGE_ALIGN(size) >> PAGE_SHIFT);
sg_free_table(&sh->sgt);
@@ -1127,10 +1146,17 @@ static void iommu_dma_unmap_resource(struct device
*dev, dma_addr_t handle,
static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
size_t alloc_size = PAGE_ALIGN(size);
- int count = alloc_size >> PAGE_SHIFT;
+ int count;
struct page *page = NULL, **pages = NULL;
+ if (dev_is_untrusted(dev))
+ alloc_size = iova_align(iovad, alloc_size);
+ count = alloc_size >> PAGE_SHIFT;
+
/* Non-coherent atomic allocation? Easy */
if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
dma_free_from_pool(dev, cpu_addr, alloc_size))
@@ -1166,12 +1192,18 @@ static void iommu_dma_free(struct device *dev, size_t
size, void *cpu_addr,
static void *iommu_dma_alloc_pages(struct device *dev, size_t size,
struct page **pagep, gfp_t gfp, unsigned long attrs)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
bool coherent = dev_is_dma_coherent(dev);
size_t alloc_size = PAGE_ALIGN(size);
int node = dev_to_node(dev);
struct page *page = NULL;
void *cpu_addr;
+ if (dev_is_untrusted(dev))
+ alloc_size = iova_align(iovad, alloc_size);
+
page = dma_alloc_contiguous(dev, alloc_size, gfp);
if (!page)
page = alloc_pages_node(node, gfp, get_order(alloc_size));
@@ -1203,6 +1235,9 @@ static void *iommu_dma_alloc_pages(struct device *dev,
size_t size,
static void *iommu_dma_alloc(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp, unsigned long attrs)
{
+ struct iommu_domain *domain = iommu_get_dma_domain(dev);
+ struct iommu_dma_cookie *cookie = domain->iova_cookie;
+ struct iova_domain *iovad = &cookie->iovad;
bool coherent = dev_is_dma_coherent(dev);
int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs);
struct page *page = NULL;
@@ -1216,6 +1251,9 @@ static void *iommu_dma_alloc(struct device *dev, size_t
size,
dma_pgprot(dev, PAGE_KERNEL, attrs), attrs);
}
+ if (dev_is_untrusted(dev))
+ size = iova_align(iovad, size);
+
if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
!gfpflags_allow_blocking(gfp) && !coherent)
page = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &cpu_addr,
--
2.25.1
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