[PATCH v10 07/10] memory: Add interface to set iommu page size mask

[Jean-Philippe Brucker]

From: Bharat Bhushan <bbhushan2@marvell.com>

Allow to set the page size mask supported by an iommu memory region.
This enables a vIOMMU to communicate the page size granule supported by
an assigned device, on hosts that use page sizes greater than 4kB.

Signed-off-by: Bharat Bhushan <bbhushan2@marvell.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
v10: Add errp parameter
---
 include/exec/memory.h | 26 ++++++++++++++++++++++++++
 softmmu/memory.c      | 13 +++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/include/exec/memory.h b/include/exec/memory.h
index dee09851622..c2da8381bec 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -382,6 +382,20 @@ struct IOMMUMemoryRegionClass {
      * @iommu: the IOMMUMemoryRegion
      */
     int (*num_indexes)(IOMMUMemoryRegion *iommu);
+
+    /*
+     * Set supported IOMMU page size
+     *
+     * If supported, allows to restrict the page size mask that can be 
supported
+     * with a given IOMMU memory region. For example, to propagate host 
physical
+     * IOMMU page size mask limitations to the virtual IOMMU.
+     *
+     * Returns 0 on success, or a negative error. In case of failure, the error
+     * object must be created.
+     */
+     int (*iommu_set_page_size_mask)(IOMMUMemoryRegion *iommu,
+                                     uint64_t page_size_mask,
+                                     Error **errp);
 };
 
 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
@@ -1389,6 +1403,18 @@ int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion 
*iommu_mr,
  */
 int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);
 
+/**
+ * memory_region_iommu_set_page_size_mask: set the supported page
+ * sizes for a given IOMMU memory region
+ *
+ * @iommu_mr: IOMMU memory region
+ * @page_size_mask: supported page size mask
+ * @errp: pointer to Error*, to store an error if it happens.
+ */
+int memory_region_iommu_set_page_size_mask(IOMMUMemoryRegion *iommu_mr,
+                                           uint64_t page_size_mask,
+                                           Error **errp);
+
 /**
  * memory_region_name: get a memory region's name
  *
diff --git a/softmmu/memory.c b/softmmu/memory.c
index fa280a19f7f..5c855a02704 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -1811,6 +1811,19 @@ static int 
memory_region_update_iommu_notify_flags(IOMMUMemoryRegion *iommu_mr,
     return ret;
 }
 
+int memory_region_iommu_set_page_size_mask(IOMMUMemoryRegion *iommu_mr,
+                                           uint64_t page_size_mask,
+                                           Error **errp)
+{
+    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);
+    int ret = 0;
+
+    if (imrc->iommu_set_page_size_mask) {
+        ret = imrc->iommu_set_page_size_mask(iommu_mr, page_size_mask, errp);
+    }
+    return ret;
+}
+
 int memory_region_register_iommu_notifier(MemoryRegion *mr,
                                           IOMMUNotifier *n, Error **errp)
 {
-- 
2.28.0