Re: [PATCH v2 4/5] ramfb: make migration conditional

[Cédric Le Goater]

On 10/2/23 13:11, marcandre.lur...@redhat.com wrote:

From: Marc-André Lureau <marcandre.lur...@redhat.com>

RAMFB migration was unsupported until now, let's make it conditional.
The following patch will prevent machines <= 8.1 to migrate it.

Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>

Maybe localize the new 'ramfb_migrate' attribute close to 'enable_ramfb'
in VFIOPCIDevice. Anyhow,

Acked-by: Cédric Le Goater <c...@redhat.com>

Thanks,

C.

---
  hw/vfio/pci.h                 | 1 +
  include/hw/display/ramfb.h    | 2 +-
  hw/display/ramfb-standalone.c | 8 +++++++-
  hw/display/ramfb.c            | 6 ++++--
  hw/vfio/display.c             | 4 ++--
  hw/vfio/pci.c                 | 1 +
  stubs/ramfb.c                 | 2 +-
  7 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index 2d836093a8..671cc78912 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -156,6 +156,7 @@ struct VFIOPCIDevice {
      OnOffAuto display;
      uint32_t display_xres;
      uint32_t display_yres;
+    bool ramfb_migrate;
      int32_t bootindex;
      uint32_t igd_gms;
      OffAutoPCIBAR msix_relo;
diff --git a/include/hw/display/ramfb.h b/include/hw/display/ramfb.h
index b33a2c467b..40063b62bd 100644
--- a/include/hw/display/ramfb.h
+++ b/include/hw/display/ramfb.h
@@ -4,7 +4,7 @@
  /* ramfb.c */
  typedef struct RAMFBState RAMFBState;
  void ramfb_display_update(QemuConsole *con, RAMFBState *s);
-RAMFBState *ramfb_setup(Error **errp);
+RAMFBState *ramfb_setup(bool migrate, Error **errp);

/* ramfb-standalone.c */

  #define TYPE_RAMFB_DEVICE "ramfb"
diff --git a/hw/display/ramfb-standalone.c b/hw/display/ramfb-standalone.c
index 8c0094397f..6bbd69ccdf 100644
--- a/hw/display/ramfb-standalone.c
+++ b/hw/display/ramfb-standalone.c
@@ -15,6 +15,7 @@ struct RAMFBStandaloneState {
      SysBusDevice parent_obj;
      QemuConsole *con;
      RAMFBState *state;
+    bool migrate;
  };

static void display_update_wrapper(void *dev)

@@ -37,9 +38,13 @@ static void ramfb_realizefn(DeviceState *dev, Error **errp)
      RAMFBStandaloneState *ramfb = RAMFB(dev);

ramfb->con = graphic_console_init(dev, 0, &wrapper_ops, dev);

-    ramfb->state = ramfb_setup(errp);
+    ramfb->state = ramfb_setup(ramfb->migrate, errp);
  }

+static Property ramfb_properties[] = {

+    DEFINE_PROP_BOOL("migrate", RAMFBStandaloneState, migrate,  true),
+    DEFINE_PROP_END_OF_LIST(),
+};
  static void ramfb_class_initfn(ObjectClass *klass, void *data)
  {
      DeviceClass *dc = DEVICE_CLASS(klass);
@@ -48,6 +53,7 @@ static void ramfb_class_initfn(ObjectClass *klass, void *data)
      dc->realize = ramfb_realizefn;
      dc->desc = "ram framebuffer standalone device";
      dc->user_creatable = true;
+    device_class_set_props(dc, ramfb_properties);
  }

static const TypeInfo ramfb_info = {

diff --git a/hw/display/ramfb.c b/hw/display/ramfb.c
index 4aaaa7d653..73e08d605f 100644
--- a/hw/display/ramfb.c
+++ b/hw/display/ramfb.c
@@ -135,7 +135,7 @@ static const VMStateDescription vmstate_ramfb = {
      }
  };

-RAMFBState *ramfb_setup(Error **errp)

+RAMFBState *ramfb_setup(bool migrate, Error **errp)
  {
      FWCfgState *fw_cfg = fw_cfg_find();
      RAMFBState *s;
@@ -147,7 +147,9 @@ RAMFBState *ramfb_setup(Error **errp)

s = g_new0(RAMFBState, 1); - vmstate_register(NULL, 0, &vmstate_ramfb, s);

+    if (migrate) {
+        vmstate_register(NULL, 0, &vmstate_ramfb, s);
+    }
      rom_add_vga("vgabios-ramfb.bin");
      fw_cfg_add_file_callback(fw_cfg, "etc/ramfb",
                               NULL, ramfb_fw_cfg_write, s,
diff --git a/hw/vfio/display.c b/hw/vfio/display.c
index bec864f482..3f6b251ccd 100644
--- a/hw/vfio/display.c
+++ b/hw/vfio/display.c
@@ -356,7 +356,7 @@ static int vfio_display_dmabuf_init(VFIOPCIDevice *vdev, 
Error **errp)
                                            &vfio_display_dmabuf_ops,
                                            vdev);
      if (vdev->enable_ramfb) {
-        vdev->dpy->ramfb = ramfb_setup(errp);
+        vdev->dpy->ramfb = ramfb_setup(vdev->ramfb_migrate, errp);
      }
      vfio_display_edid_init(vdev);
      return 0;
@@ -483,7 +483,7 @@ static int vfio_display_region_init(VFIOPCIDevice *vdev, 
Error **errp)
                                            &vfio_display_region_ops,
                                            vdev);
      if (vdev->enable_ramfb) {
-        vdev->dpy->ramfb = ramfb_setup(errp);
+        vdev->dpy->ramfb = ramfb_setup(vdev->ramfb_migrate, errp);
      }
      return 0;
  }
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 3b2ca3c24c..6575b8f32d 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3484,6 +3484,7 @@ static const TypeInfo vfio_pci_dev_info = {

static Property vfio_pci_dev_nohotplug_properties[] = {

      DEFINE_PROP_BOOL("ramfb", VFIOPCIDevice, enable_ramfb, false),
+    DEFINE_PROP_BOOL("ramfb-migrate", VFIOPCIDevice, ramfb_migrate,  true),
      DEFINE_PROP_END_OF_LIST(),
  };

diff --git a/stubs/ramfb.c b/stubs/ramfb.c

index 48143f3354..8869a5db09 100644
--- a/stubs/ramfb.c
+++ b/stubs/ramfb.c
@@ -6,7 +6,7 @@ void ramfb_display_update(QemuConsole *con, RAMFBState *s)
  {
  }

-RAMFBState *ramfb_setup(Error **errp)

+RAMFBState *ramfb_setup(bool migrate, Error **errp)
  {
      error_setg(errp, "ramfb support not available");
      return NULL;