[PATCH 3/5] vfio/iommufd: Add IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR flag support

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

Pass IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR when doing the last dirty
bitmap query right before unmap, no PTEs flushes. This accelerates the
query without issue because unmap will tear down the mapping anyway.

Add a new element dirty_tracking_flags in VFIOIOMMUFDContainer to
be used for the flags of iommufd dirty tracking. Currently it is
set to either IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR or 0 based on
the scenario.

Co-developed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
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/vfio-iommufd.h   | 1 +
 include/system/iommufd.h | 2 +-
 backends/iommufd.c       | 5 +++--
 hw/vfio/iommufd.c        | 6 +++++-
 backends/trace-events    | 2 +-
 5 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/hw/vfio/vfio-iommufd.h b/hw/vfio/vfio-iommufd.h
index 07ea0f4304..e0af241c75 100644
--- a/hw/vfio/vfio-iommufd.h
+++ b/hw/vfio/vfio-iommufd.h
@@ -26,6 +26,7 @@ typedef struct VFIOIOMMUFDContainer {
     VFIOContainerBase bcontainer;
     IOMMUFDBackend *be;
     uint32_t ioas_id;
+    uint64_t dirty_tracking_flags;
     QLIST_HEAD(, VFIOIOASHwpt) hwpt_list;
 } VFIOIOMMUFDContainer;
 
diff --git a/include/system/iommufd.h b/include/system/iommufd.h
index c9c72ffc45..63898e7b0d 100644
--- a/include/system/iommufd.h
+++ b/include/system/iommufd.h
@@ -64,7 +64,7 @@ bool iommufd_backend_set_dirty_tracking(IOMMUFDBackend *be, uint32_t hwpt_id,
 bool iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be, uint32_t hwpt_id,
                                       uint64_t iova, ram_addr_t size,
                                       uint64_t page_size, uint64_t *data,
-                                      Error **errp);
+                                      uint64_t flags, Error **errp);
 bool iommufd_backend_invalidate_cache(IOMMUFDBackend *be, uint32_t id,
                                       uint32_t data_type, uint32_t entry_len,
                                       uint32_t *entry_num, void *data,
diff --git a/backends/iommufd.c b/backends/iommufd.c
index 2a33c7ab0b..3c4f6157e2 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -361,7 +361,7 @@ bool iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be,
                                       uint32_t hwpt_id,
                                       uint64_t iova, ram_addr_t size,
                                       uint64_t page_size, uint64_t *data,
-                                      Error **errp)
+                                      uint64_t flags, Error **errp)
 {
     int ret;
     struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap = {
@@ -371,11 +371,12 @@ bool iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be,
         .length = size,
         .page_size = page_size,
         .data = (uintptr_t)data,
+        .flags = flags,
     };
 
     ret = ioctl(be->fd, IOMMU_HWPT_GET_DIRTY_BITMAP, &get_dirty_bitmap);
     trace_iommufd_backend_get_dirty_bitmap(be->fd, hwpt_id, iova, size,
-                                           page_size, ret ? errno : 0);
+                                           flags, page_size, ret ? errno : 0);
     if (ret) {
         error_setg_errno(errp, errno,
                          "IOMMU_HWPT_GET_DIRTY_BITMAP (iova: 0x%"HWADDR_PRIx
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index 0057488ce9..c897aa6b17 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -62,7 +62,7 @@ static int iommufd_cdev_unmap_one(const VFIOContainerBase *bcontainer,
                                   hwaddr iova, ram_addr_t size,
                                   IOMMUTLBEntry *iotlb)
 {
-    const VFIOIOMMUFDContainer *container =
+    VFIOIOMMUFDContainer *container =
         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
     bool need_dirty_sync = false;
     Error *local_err = NULL;
@@ -73,9 +73,12 @@ static int iommufd_cdev_unmap_one(const VFIOContainerBase *bcontainer,
     if (iotlb && vfio_container_dirty_tracking_is_started(bcontainer)) {
         if (!vfio_container_devices_dirty_tracking_is_supported(bcontainer) &&
             bcontainer->dirty_pages_supported) {
+            container->dirty_tracking_flags =
+                                      IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR;
             ret = vfio_container_query_dirty_bitmap(bcontainer, iova, size,
                                                     iotlb->translated_addr,
                                                     &local_err);
+            container->dirty_tracking_flags = 0;
             if (ret) {
                 error_report_err(local_err);
             }
@@ -248,6 +251,7 @@ static int iommufd_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
         if (!iommufd_backend_get_dirty_bitmap(container->be, hwpt->hwpt_id,
                                               iova, size, page_size,
                                               (uint64_t *)vbmap->bitmap,
+                                              container->dirty_tracking_flags,
                                               errp)) {
             return -EINVAL;
         }
diff --git a/backends/trace-events b/backends/trace-events
index 56132d3fd2..e1992ba12f 100644
--- a/backends/trace-events
+++ b/backends/trace-events
@@ -19,5 +19,5 @@ iommufd_backend_alloc_ioas(int iommufd, uint32_t ioas) " iommufd=%d ioas=%d"
 iommufd_backend_alloc_hwpt(int iommufd, uint32_t dev_id, uint32_t pt_id, uint32_t flags, uint32_t hwpt_type, uint32_t len, uint64_t data_ptr, uint32_t out_hwpt_id, int ret) " iommufd=%d dev_id=%u pt_id=%u flags=0x%x hwpt_type=%u len=%u data_ptr=0x%"PRIx64" out_hwpt=%u (%d)"
 iommufd_backend_free_id(int iommufd, uint32_t id, int ret) " iommufd=%d id=%d (%d)"
 iommufd_backend_set_dirty(int iommufd, uint32_t hwpt_id, bool start, int ret) " iommufd=%d hwpt=%u enable=%d (%d)"
-iommufd_backend_get_dirty_bitmap(int iommufd, uint32_t hwpt_id, uint64_t iova, uint64_t size, uint64_t page_size, int ret) " iommufd=%d hwpt=%u iova=0x%"PRIx64" size=0x%"PRIx64" page_size=0x%"PRIx64" (%d)"
+iommufd_backend_get_dirty_bitmap(int iommufd, uint32_t hwpt_id, uint64_t iova, uint64_t size, uint64_t flags, uint64_t page_size, int ret) " iommufd=%d hwpt=%u iova=0x%"PRIx64" size=0x%"PRIx64" flags=0x%"PRIx64" page_size=0x%"PRIx64" (%d)"
 iommufd_backend_invalidate_cache(int iommufd, uint32_t id, uint32_t data_type, uint32_t entry_len, uint32_t entry_num, uint32_t done_num, uint64_t data_ptr, int ret) " iommufd=%d id=%u data_type=%u entry_len=%u entry_num=%u done_num=%u data_ptr=0x%"PRIx64" (%d)"
-- 
2.47.1