On 13/06/2019 11:20, Yoshihiro Shimoda wrote:
This patch adds an exported function to get minimum page size for
a domain. This patch also modifies similar codes on the iommu.c.
Heh, seeing this gave me a genuine déjà vu moment...
...but it turns out I actually *have* reviewed this patch before :)
https://lore.kernel.org/lkml/05eca601-0264-8141-ceeb-7ef7ad5d5650@xxxxxxx/
Robin.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
drivers/iommu/iommu.c | 18 +++++++++++++++---
include/linux/iommu.h | 1 +
2 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 2a90638..7ed16af 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -280,6 +280,18 @@ iommu_insert_device_resv_regions(struct list_head *dev_resv_regions,
return ret;
}
+/**
+ * iommu_get_minimum_page_size - get minimum page size for a domain
+ * @domain: the domain
+ *
+ * Allow iommu driver to get a minimum page size for a domain.
+ */
+unsigned long iommu_get_minimum_page_size(struct iommu_domain *domain)
+{
+ return 1UL << __ffs(domain->pgsize_bitmap);
+}
+EXPORT_SYMBOL_GPL(iommu_get_minimum_page_size);
+
int iommu_get_group_resv_regions(struct iommu_group *group,
struct list_head *head)
{
@@ -558,7 +570,7 @@ static int iommu_group_create_direct_mappings(struct iommu_group *group,
BUG_ON(!domain->pgsize_bitmap);
- pg_size = 1UL << __ffs(domain->pgsize_bitmap);
+ pg_size = iommu_get_minimum_page_size(domain);
INIT_LIST_HEAD(&mappings);
iommu_get_resv_regions(dev, &mappings);
@@ -1595,7 +1607,7 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
return -EINVAL;
/* find out the minimum page size supported */
- min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+ min_pagesz = iommu_get_minimum_page_size(domain);
/*
* both the virtual address and the physical one, as well as
@@ -1655,7 +1667,7 @@ static size_t __iommu_unmap(struct iommu_domain *domain,
return 0;
/* find out the minimum page size supported */
- min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+ min_pagesz = iommu_get_minimum_page_size(domain);
/*
* The virtual address, as well as the size of the mapping, must be
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 91af22a..7e53b43 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -366,6 +366,7 @@ extern int iommu_request_dma_domain_for_dev(struct device *dev);
extern struct iommu_resv_region *
iommu_alloc_resv_region(phys_addr_t start, size_t length, int prot,
enum iommu_resv_type type);
+extern unsigned long iommu_get_minimum_page_size(struct iommu_domain *domain);
extern int iommu_get_group_resv_regions(struct iommu_group *group,
struct list_head *head);
