[PATCH v5 4/7] vfio/migration: Return bool type for some vfio migration related functions

[Zhenzhong Duan]

Include:
vfio_block_multiple_devices_migration(),
vfio_block_giommu_migration(),
vfio_block_migration(),
vfio_migration_realize().

Suggested-by: Cédric Le Goater <c...@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
---
 hw/vfio/common.c              | 16 ++++++++--------
 hw/vfio/migration.c           | 19 ++++++++++++-------
 include/hw/vfio/vfio-common.h |  6 +++---
 3 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 77e2ee0e5c6e..00fef5aa08be 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -381,19 +381,19 @@ static unsigned int vfio_migratable_device_num(void)
     return device_num;
 }
 
-int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp)
+bool vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp)
 {
     int ret;
 
     if (multiple_devices_migration_blocker ||
         vfio_migratable_device_num() <= 1) {
-        return 0;
+        return true;
     }
 
     if (vbasedev->enable_migration == ON_OFF_AUTO_ON) {
         error_setg(errp, "Migration is currently not supported with multiple "
                          "VFIO devices");
-        return -EINVAL;
+        return false;
     }
 
     error_setg(&multiple_devices_migration_blocker,
@@ -405,7 +405,7 @@ int vfio_block_multiple_devices_migration(VFIODevice 
*vbasedev, Error **errp)
         multiple_devices_migration_blocker = NULL;
     }
 
-    return ret;
+    return !ret;
 }
 
 void vfio_unblock_multiple_devices_migration(void)
@@ -433,19 +433,19 @@ static bool vfio_viommu_preset(void)
     return false;
 }
 
-int vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp)
+bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp)
 {
     int ret;
 
     if (giommu_migration_blocker ||
         !vfio_viommu_preset()) {
-        return 0;
+        return true;
     }
 
     if (vbasedev->enable_migration == ON_OFF_AUTO_ON) {
         error_setg(errp,
                    "Migration is currently not supported with vIOMMU enabled");
-        return -EINVAL;
+        return false;
     }
 
     error_setg(&giommu_migration_blocker,
@@ -456,7 +456,7 @@ int vfio_block_giommu_migration(VFIODevice *vbasedev, Error 
**errp)
         giommu_migration_blocker = NULL;
     }
 
-    return ret;
+    return !ret;
 }
 
 void vfio_migration_finalize(void)
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 1db7d52ab2c1..09fa4714a085 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -802,13 +802,13 @@ static int vfio_migration_init(VFIODevice *vbasedev)
     return 0;
 }
 
-static int vfio_block_migration(VFIODevice *vbasedev, Error *err, Error **errp)
+static bool vfio_block_migration(VFIODevice *vbasedev, Error *err, Error 
**errp)
 {
     int ret;
 
     if (vbasedev->enable_migration == ON_OFF_AUTO_ON) {
         error_propagate(errp, err);
-        return -EINVAL;
+        return false;
     }
 
     vbasedev->migration_blocker = error_copy(err);
@@ -820,7 +820,7 @@ static int vfio_block_migration(VFIODevice *vbasedev, Error 
*err, Error **errp)
         vbasedev->migration_blocker = NULL;
     }
 
-    return ret;
+    return !ret;
 }
 
 /* ---------------------------------------------------------------------- */
@@ -835,7 +835,12 @@ void vfio_reset_bytes_transferred(void)
     bytes_transferred = 0;
 }
 
-int vfio_migration_realize(VFIODevice *vbasedev, Error **errp)
+/*
+ * Return true when either migration initialized or blocker registered.
+ * Currently only return false when adding blocker fails which will
+ * de-register vfio device.
+ */
+bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp)
 {
     Error *err = NULL;
     int ret;
@@ -874,17 +879,17 @@ int vfio_migration_realize(VFIODevice *vbasedev, Error 
**errp)
     }
 
     ret = vfio_block_multiple_devices_migration(vbasedev, errp);
-    if (ret) {
+    if (!ret) {
         return ret;
     }
 
     ret = vfio_block_giommu_migration(vbasedev, errp);
-    if (ret) {
+    if (!ret) {
         return ret;
     }
 
     trace_vfio_migration_realize(vbasedev->name);
-    return 0;
+    return true;
 }
 
 void vfio_migration_exit(VFIODevice *vbasedev)
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 93429b9abba0..b3014ece2edf 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -225,9 +225,9 @@ typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
 extern VFIOGroupList vfio_group_list;
 
 bool vfio_mig_active(void);
-int vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp);
+bool vfio_block_multiple_devices_migration(VFIODevice *vbasedev, Error **errp);
 void vfio_unblock_multiple_devices_migration(void);
-int vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp);
+bool vfio_block_giommu_migration(VFIODevice *vbasedev, Error **errp);
 int64_t vfio_mig_bytes_transferred(void);
 void vfio_reset_bytes_transferred(void);
 
@@ -252,7 +252,7 @@ int vfio_spapr_create_window(VFIOContainer *container,
 int vfio_spapr_remove_window(VFIOContainer *container,
                              hwaddr offset_within_address_space);
 
-int vfio_migration_realize(VFIODevice *vbasedev, Error **errp);
+bool vfio_migration_realize(VFIODevice *vbasedev, Error **errp);
 void vfio_migration_exit(VFIODevice *vbasedev);
 void vfio_migration_finalize(void);
 
-- 
2.34.1