From: Avihai Horon <avihaih@nvidia.com>
Date: Wed, 18 Dec 2024 13:40:16 +0000 (+0200)
Subject: vfio/container: Add dirty tracking started flag
X-Git-Tag: v10.0.0-rc0~106^2~6
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d77e85dbd7655cc41af51df74c077d8b31aee93c;p=thirdparty%2Fqemu.git

vfio/container: Add dirty tracking started flag

Add a flag to VFIOContainerBase that indicates whether dirty tracking
has been started for the container or not.

This will be used in the following patches to allow dirty page syncs
only if dirty tracking has been started.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Tested-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20241218134022.21264-2-avihaih@nvidia.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---

diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c
index 6f86c37d971..749a3fd29dd 100644
--- a/hw/vfio/container-base.c
+++ b/hw/vfio/container-base.c
@@ -64,13 +64,23 @@ int vfio_container_set_dirty_page_tracking(VFIOContainerBase *bcontainer,
                                            bool start, Error **errp)
 {
     VFIOIOMMUClass *vioc = VFIO_IOMMU_GET_CLASS(bcontainer);
+    int ret;
 
     if (!bcontainer->dirty_pages_supported) {
         return 0;
     }
 
     g_assert(vioc->set_dirty_page_tracking);
-    return vioc->set_dirty_page_tracking(bcontainer, start, errp);
+    if (bcontainer->dirty_pages_started == start) {
+        return 0;
+    }
+
+    ret = vioc->set_dirty_page_tracking(bcontainer, start, errp);
+    if (!ret) {
+        bcontainer->dirty_pages_started = start;
+    }
+
+    return ret;
 }
 
 int vfio_container_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
diff --git a/include/hw/vfio/vfio-container-base.h b/include/hw/vfio/vfio-container-base.h
index 62a8b60d87d..4cff9943ab4 100644
--- a/include/hw/vfio/vfio-container-base.h
+++ b/include/hw/vfio/vfio-container-base.h
@@ -44,6 +44,7 @@ typedef struct VFIOContainerBase {
     unsigned long pgsizes;
     unsigned int dma_max_mappings;
     bool dirty_pages_supported;
+    bool dirty_pages_started; /* Protected by BQL */
     QLIST_HEAD(, VFIOGuestIOMMU) giommu_list;
     QLIST_HEAD(, VFIORamDiscardListener) vrdl_list;
     QLIST_ENTRY(VFIOContainerBase) next;