[PATCH 3/5] iommu: Allow selecting page sizes per domain
Robin Murphy
robin.murphy at arm.com
Thu Apr 7 17:42:06 UTC 2016
Many IOMMUs support multiple page table formats, meaning that any given
domain may only support a subset of the hardware page sizes presented in
iommu_ops->pgsize_bitmap. There are also certain use-cases where the
creator of a domain may want to control which page sizes are used, for
example to force the use of hugepage mappings to reduce pagetable walk
depth.
To this end, add a per-domain pgsize_bitmap to represent the subset of
page sizes actually in use, to make it possible for domains with
different requirements to coexist.
Signed-off-by: Will Deacon <will.deacon at arm.com>
[rm: hijacked and rebased original patch with new commit message]
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
drivers/iommu/dma-iommu.c | 2 +-
drivers/iommu/iommu.c | 22 ++++++++++++----------
drivers/iommu/mtk_iommu.c | 2 +-
drivers/vfio/vfio_iommu_type1.c | 2 +-
include/linux/iommu.h | 3 ++-
5 files changed, 17 insertions(+), 14 deletions(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 58f2fe6..6edc852 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -94,7 +94,7 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size
return -ENODEV;
/* Use the smallest supported page size for IOVA granularity */
- order = __ffs(domain->ops->pgsize_bitmap);
+ order = __ffs(domain->pgsize_bitmap);
base_pfn = max_t(unsigned long, 1, base >> order);
end_pfn = (base + size - 1) >> order;
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b9df141..ab4d014 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -337,9 +337,9 @@ static int iommu_group_create_direct_mappings(struct iommu_group *group,
if (!domain || domain->type != IOMMU_DOMAIN_DMA)
return 0;
- BUG_ON(!domain->ops->pgsize_bitmap);
+ BUG_ON(!domain->pgsize_bitmap);
- pg_size = 1UL << __ffs(domain->ops->pgsize_bitmap);
+ pg_size = 1UL << __ffs(domain->pgsize_bitmap);
INIT_LIST_HEAD(&mappings);
iommu_get_dm_regions(dev, &mappings);
@@ -1073,6 +1073,8 @@ static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
domain->ops = bus->iommu_ops;
domain->type = type;
+ /* Assume all sizes by default; the driver may override this later */
+ domain->pgsize_bitmap = bus->iommu_ops->pgsize_bitmap;
return domain;
}
@@ -1297,7 +1299,7 @@ static size_t iommu_pgsize(struct iommu_domain *domain,
pgsize = (1UL << (pgsize_idx + 1)) - 1;
/* throw away page sizes not supported by the hardware */
- pgsize &= domain->ops->pgsize_bitmap;
+ pgsize &= domain->pgsize_bitmap;
/* make sure we're still sane */
BUG_ON(!pgsize);
@@ -1319,14 +1321,14 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
int ret = 0;
if (unlikely(domain->ops->map == NULL ||
- domain->ops->pgsize_bitmap == 0UL))
+ domain->pgsize_bitmap == 0UL))
return -ENODEV;
if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
return -EINVAL;
/* find out the minimum page size supported */
- min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
/*
* both the virtual address and the physical one, as well as
@@ -1373,14 +1375,14 @@ size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size)
unsigned long orig_iova = iova;
if (unlikely(domain->ops->unmap == NULL ||
- domain->ops->pgsize_bitmap == 0UL))
+ domain->pgsize_bitmap == 0UL))
return -ENODEV;
if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))
return -EINVAL;
/* find out the minimum page size supported */
- min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
/*
* The virtual address, as well as the size of the mapping, must be
@@ -1426,10 +1428,10 @@ size_t default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
unsigned int i, min_pagesz;
int ret;
- if (unlikely(domain->ops->pgsize_bitmap == 0UL))
+ if (unlikely(domain->pgsize_bitmap == 0UL))
return 0;
- min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap);
+ min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
for_each_sg(sg, s, nents, i) {
phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
@@ -1510,7 +1512,7 @@ int iommu_domain_get_attr(struct iommu_domain *domain,
break;
case DOMAIN_ATTR_PAGING:
paging = data;
- *paging = (domain->ops->pgsize_bitmap != 0UL);
+ *paging = (domain->pgsize_bitmap != 0UL);
break;
case DOMAIN_ATTR_WINDOWS:
count = data;
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index db74553..c3043d8 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -269,7 +269,7 @@ static int mtk_iommu_domain_finalise(struct mtk_iommu_data *data)
}
/* Update our support page sizes bitmap */
- mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;
+ dom->domain.pgsize_bitmap = dom->cfg.pgsize_bitmap;
writel(data->m4u_dom->cfg.arm_v7s_cfg.ttbr[0],
data->base + REG_MMU_PT_BASE_ADDR);
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 75b24e9..15a6582 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -407,7 +407,7 @@ static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
mutex_lock(&iommu->lock);
list_for_each_entry(domain, &iommu->domain_list, next)
- bitmap &= domain->domain->ops->pgsize_bitmap;
+ bitmap &= domain->domain->pgsize_bitmap;
mutex_unlock(&iommu->lock);
/*
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 45b055d..664683a 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -79,6 +79,7 @@ struct iommu_domain_geometry {
struct iommu_domain {
unsigned type;
const struct iommu_ops *ops;
+ unsigned long pgsize_bitmap; /* Bitmap of page sizes in use */
iommu_fault_handler_t handler;
void *handler_token;
struct iommu_domain_geometry geometry;
@@ -156,7 +157,7 @@ struct iommu_dm_region {
* @domain_set_windows: Set the number of windows for a domain
* @domain_get_windows: Return the number of windows for a domain
* @of_xlate: add OF master IDs to iommu grouping
- * @pgsize_bitmap: bitmap of supported page sizes
+ * @pgsize_bitmap: bitmap of all possible supported page sizes
*/
struct iommu_ops {
bool (*capable)(enum iommu_cap);
--
2.7.3.dirty
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