[PULL,04/12] vfio/common: Change vfio_devices_all_running_and_saving() logic to equivalent one

Commit Message

Alex Williamson Feb. 16, 2023, 11:02 p.m. UTC

From: Avihai Horon <[e-mail]>

vfio_devices_all_running_and_saving() is used to check if migration is
in pre-copy phase. This is done by checking if migration is in setup or
active states and if all VFIO devices are in pre-copy state, i.e.
_SAVING | _RUNNING.

In VFIO migration protocol v2 pre-copy support is made optional. Hence,
a matching v2 protocol pre-copy state can't be used here.

As preparation for adding v2 protocol, change
vfio_devices_all_running_and_saving() logic such that it doesn't use the
VFIO pre-copy state.

The new equivalent logic checks if migration is in active state and if
all VFIO devices are in running state [1]. No functional changes
intended.

[1] Note that checking if migration is in setup or active states and if
all VFIO devices are in running state doesn't guarantee that we are in
pre-copy phase, thus we check if migration is only in active state.

Signed-off-by: Avihai Horon <[e-mail]>
Reviewed-by: Cédric Le Goater <[e-mail]>
Reviewed-by: Juan Quintela <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alex Williamson <[e-mail]>
---
 hw/vfio/common.c |   17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

Patch

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index f6dd5715492e..3a35f4afad64 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -40,6 +40,7 @@ 
 #include "trace.h"
 #include "qapi/error.h"
 #include "migration/migration.h"
+#include "migration/misc.h"
 #include "sysemu/tpm.h"
 
 VFIOGroupList vfio_group_list =
@@ -363,13 +364,16 @@  static bool vfio_devices_all_dirty_tracking(VFIOContainer *container)
     return true;
 }
 
-static bool vfio_devices_all_running_and_saving(VFIOContainer *container)
+/*
+ * Check if all VFIO devices are running and migration is active, which is
+ * essentially equivalent to the migration being in pre-copy phase.
+ */
+static bool vfio_devices_all_running_and_mig_active(VFIOContainer *container)
 {
     VFIOGroup *group;
     VFIODevice *vbasedev;
-    MigrationState *ms = migrate_get_current();
 
-    if (!migration_is_setup_or_active(ms->state)) {
+    if (!migration_is_active(migrate_get_current())) {
         return false;
     }
 
@@ -381,8 +385,7 @@  static bool vfio_devices_all_running_and_saving(VFIOContainer *container)
                 return false;
             }
 
-            if ((migration->device_state & VFIO_DEVICE_STATE_V1_SAVING) &&
-                (migration->device_state & VFIO_DEVICE_STATE_V1_RUNNING)) {
+            if (migration->device_state & VFIO_DEVICE_STATE_V1_RUNNING) {
                 continue;
             } else {
                 return false;
@@ -461,7 +464,7 @@  static int vfio_dma_unmap(VFIOContainer *container,
     };
 
     if (iotlb && container->dirty_pages_supported &&
-        vfio_devices_all_running_and_saving(container)) {
+        vfio_devices_all_running_and_mig_active(container)) {
         return vfio_dma_unmap_bitmap(container, iova, size, iotlb);
     }
 
@@ -488,7 +491,7 @@  static int vfio_dma_unmap(VFIOContainer *container,
         return -errno;
     }
 
-    if (iotlb && vfio_devices_all_running_and_saving(container)) {
+    if (iotlb && vfio_devices_all_running_and_mig_active(container)) {
         cpu_physical_memory_set_dirty_range(iotlb->translated_addr, size,
                                             tcg_enabled() ? DIRTY_CLIENTS_ALL :
                                             DIRTY_CLIENTS_NOCODE);