[PATCH 1/5] vfio/iommufd: Add framework code to support getting dirty bitmap before unmap

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

Currently we support device and iommu dirty tracking, device dirty
tracking is preferred.

Add the framework code in iommufd_cdev_unmap_one() to choose either
device or iommu dirty tracking, just like vfio_legacy_dma_unmap_one().

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Tested-by: Giovannio Cabiddu <giovanni.cabiddu@intel.com>
---
 hw/vfio/iommufd.c | 56 +++++++++++++++++++++++++++++++++++++----------
 1 file changed, 45 insertions(+), 11 deletions(-)

diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index 48c590b6a9..b5d6e54c45 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -58,33 +58,67 @@ static int iommufd_cdev_map_file(const VFIOContainerBase *bcontainer,
                                         iova, size, fd, start, readonly);
 }
 
-static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
-                              hwaddr iova, ram_addr_t size,
-                              IOMMUTLBEntry *iotlb, bool unmap_all)
+static int iommufd_cdev_unmap_one(const VFIOContainerBase *bcontainer,
+                                  hwaddr iova, ram_addr_t size,
+                                  IOMMUTLBEntry *iotlb)
 {
     const VFIOIOMMUFDContainer *container =
         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
+    bool need_dirty_sync = false;
+    Error *local_err = NULL;
+    IOMMUFDBackend *be = container->be;
+    uint32_t ioas_id = container->ioas_id;
+    int ret;
+
+    if (iotlb && vfio_container_dirty_tracking_is_started(bcontainer)) {
+        if (!vfio_container_devices_dirty_tracking_is_supported(bcontainer) &&
+            bcontainer->dirty_pages_supported) {
+            /* TODO: query dirty bitmap before DMA unmap */
+            return iommufd_backend_unmap_dma(be, ioas_id, iova, size);
+        }
+
+        need_dirty_sync = true;
+    }
+
+    ret = iommufd_backend_unmap_dma(be, ioas_id, iova, size);
+    if (ret) {
+        return ret;
+    }
 
+    if (need_dirty_sync) {
+        ret = vfio_container_query_dirty_bitmap(bcontainer, iova, size,
+                                                iotlb->translated_addr,
+                                                &local_err);
+        if (ret) {
+            error_report_err(local_err);
+            return ret;
+        }
+    }
+
+    return 0;
+}
+
+static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
+                              hwaddr iova, ram_addr_t size,
+                              IOMMUTLBEntry *iotlb, bool unmap_all)
+{
     /* unmap in halves */
     if (unmap_all) {
         Int128 llsize = int128_rshift(int128_2_64(), 1);
         int ret;
 
-        ret = iommufd_backend_unmap_dma(container->be, container->ioas_id,
-                                        0, int128_get64(llsize));
+        ret = iommufd_cdev_unmap_one(bcontainer, 0, int128_get64(llsize),
+                                     iotlb);
 
         if (ret == 0) {
-            ret = iommufd_backend_unmap_dma(container->be, container->ioas_id,
-                                            int128_get64(llsize),
-                                            int128_get64(llsize));
+            ret = iommufd_cdev_unmap_one(bcontainer, int128_get64(llsize),
+                                         int128_get64(llsize), iotlb);
         }
 
         return ret;
     }
 
-    /* TODO: Handle dma_unmap_bitmap with iotlb args (migration) */
-    return iommufd_backend_unmap_dma(container->be,
-                                     container->ioas_id, iova, size);
+    return iommufd_cdev_unmap_one(bcontainer, iova, size, iotlb);
 }
 
 static bool iommufd_cdev_kvm_device_add(VFIODevice *vbasedev, Error **errp)
-- 
2.47.1