Merge tag 'ui-pull-request' of https://gitlab.com/marcandre.lureau/qemu into staging

UI-related fixes & shareable 2d memory with -display dbus

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# gpg: Signature made Mon 14 Oct 2024 14:38:26 BST
# gpg:                using RSA key 87A9BD933F87C606D276F62DDAE8E10975969CE5
# gpg:                issuer "marcandre.lureau@redhat.com"
# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg:                 aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276  F62D DAE8 E109 7596 9CE5

* tag 'ui-pull-request' of https://gitlab.com/marcandre.lureau/qemu:
  audio/pw: Report more accurate error when connecting to PipeWire fails
  tests: add basic -display dbus Map.Unix test
  ui: refactor using a common qemu_pixman_shareable
  virtio-gpu: allocate shareable 2d resources on !win32
  ui/dbus: implement Unix.Map
  ui/dbus: add Listener.Unix.Map interface XML
  ui/dbus: make Listener.Win32.Map win32-specific
  meson: find_program('gdbus-codegen') directly
  ui/surface: allocate shared memory on !win32
  ui/dbus: add trace for can_share_map
  ui/dbus: do not limit to one listener per connection / bus name
  ui/pixman: generalize shared_image_destroy
  util/memfd: report potential errors on free
  ui/dbus: discard pending CursorDefine on new one
  ui/dbus: discard display messages on disable
  ui/dbus: fix filtering all update messages
  ui/win32: fix potential use-after-free with dbus shared memory
  ui/dbus: fix leak on message filtering
  hw/audio/hda: fix memory leak on audio setup
  hw/audio/hda: free timer on exit

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

audio/pwaudio.c

@@ -769,13 +769,15 @@ qpw_audio_init(Audiodev *dev, Error **errp)
     pw->core = pw_context_connect(pw->context, NULL, 0);
     if (pw->core == NULL) {
         pw_thread_loop_unlock(pw->thread_loop);
-        goto fail_error;
+        error_setg_errno(errp, errno, "Failed to connect to PipeWire instance");
+        goto fail;
     }
 
     if (pw_core_add_listener(pw->core, &pw->core_listener,
                              &core_events, pw) < 0) {
         pw_thread_loop_unlock(pw->thread_loop);
-        goto fail_error;
+        error_setg(errp, "Failed to add PipeWire listener");
+        goto fail;
     }
     if (wait_resync(pw) < 0) {
         pw_thread_loop_unlock(pw->thread_loop);
@@ -785,8 +787,6 @@ qpw_audio_init(Audiodev *dev, Error **errp)
 
     return g_steal_pointer(&pw);
 
-fail_error:
-    error_setg(errp, "Failed to initialize PW context");
 fail:
     if (pw->thread_loop) {
         pw_thread_loop_stop(pw->thread_loop);

hw/audio/hda-codec.c

@@ -472,6 +472,24 @@ static void hda_audio_set_amp(HDAAudioStream *st)
     }
 }
 
+static void hda_close_stream(HDAAudioState *a, HDAAudioStream *st)
+{
+    if (st->node == NULL) {
+        return;
+    }
+    if (a->use_timer) {
+        timer_free(st->buft);
+        st->buft = NULL;
+    }
+    if (st->output) {
+        AUD_close_out(&a->card, st->voice.out);
+        st->voice.out = NULL;
+    } else {
+        AUD_close_in(&a->card, st->voice.in);
+        st->voice.in = NULL;
+    }
+}
+
 static void hda_audio_setup(HDAAudioStream *st)
 {
     bool use_timer = st->state->use_timer;
@@ -484,6 +502,7 @@ static void hda_audio_setup(HDAAudioStream *st)
     trace_hda_audio_format(st->node->name, st->as.nchannels,
                            fmt2name[st->as.fmt], st->as.freq);
 
+    hda_close_stream(st->state, st);
     if (st->output) {
         if (use_timer) {
             cb = hda_audio_output_cb;
@@ -741,23 +760,11 @@ static void hda_audio_init(HDACodecDevice *hda,
 static void hda_audio_exit(HDACodecDevice *hda)
 {
     HDAAudioState *a = HDA_AUDIO(hda);
-    HDAAudioStream *st;
     int i;
 
     dprint(a, 1, "%s\n", __func__);
     for (i = 0; i < ARRAY_SIZE(a->st); i++) {
-        st = a->st + i;
-        if (st->node == NULL) {
-            continue;
-        }
-        if (a->use_timer) {
-            timer_del(st->buft);
-        }
-        if (st->output) {
-            AUD_close_out(&a->card, st->voice.out);
-        } else {
-            AUD_close_in(&a->card, st->voice.in);
-        }
+        hda_close_stream(a, a->st + i);
     }
     AUD_remove_card(&a->card);
 }

hw/display/virtio-gpu.c

@@ -28,6 +28,7 @@
 #include "hw/virtio/virtio-bus.h"
 #include "hw/qdev-properties.h"
 #include "qemu/log.h"
+#include "qemu/memfd.h"
 #include "qemu/module.h"
 #include "qapi/error.h"
 #include "qemu/error-report.h"
@@ -238,16 +239,6 @@ static uint32_t calc_image_hostmem(pixman_format_code_t pformat,
     return height * stride;
 }
 
-#ifdef WIN32
-static void
-win32_pixman_image_destroy(pixman_image_t *image, void *data)
-{
-    HANDLE handle = data;
-
-    qemu_win32_map_free(pixman_image_get_data(image), handle, &error_warn);
-}
-#endif
-
 static void virtio_gpu_resource_create_2d(VirtIOGPU *g,
                                           struct virtio_gpu_ctrl_command *cmd)
 {
@@ -294,28 +285,20 @@ static void virtio_gpu_resource_create_2d(VirtIOGPU *g,
 
     res->hostmem = calc_image_hostmem(pformat, c2d.width, c2d.height);
     if (res->hostmem + g->hostmem < g->conf_max_hostmem) {
-        void *bits = NULL;
-#ifdef WIN32
-        bits = qemu_win32_map_alloc(res->hostmem, &res->handle, &error_warn);
-        if (!bits) {
+        if (!qemu_pixman_image_new_shareable(
+                &res->image,
+                &res->share_handle,
+                "virtio-gpu res",
+                pformat,
+                c2d.width,
+                c2d.height,
+                c2d.height ? res->hostmem / c2d.height : 0,
+                &error_warn)) {
             goto end;
         }
-#endif
-        res->image = pixman_image_create_bits(
-            pformat,
-            c2d.width,
-            c2d.height,
-            bits, c2d.height ? res->hostmem / c2d.height : 0);
-#ifdef WIN32
-        if (res->image) {
-            pixman_image_set_destroy_function(res->image, win32_pixman_image_destroy, res->handle);
-        }
-#endif
     }
 
-#ifdef WIN32
 end:
-#endif
     if (!res->image) {
         qemu_log_mask(LOG_GUEST_ERROR,
                       "%s: resource creation failed %d %d %d\n",
@@ -686,9 +669,7 @@ static bool virtio_gpu_do_set_scanout(VirtIOGPU *g,
 
         /* realloc the surface ptr */
         scanout->ds = qemu_create_displaysurface_pixman(rect);
-#ifdef WIN32
-        qemu_displaysurface_win32_set_handle(scanout->ds, res->handle, fb->offset);
-#endif
+        qemu_displaysurface_set_share_handle(scanout->ds, res->share_handle, fb->offset);
 
         pixman_image_unref(rect);
         dpy_gfx_replace_surface(g->parent_obj.scanout[scanout_id].con,
@@ -1284,7 +1265,6 @@ static int virtio_gpu_load(QEMUFile *f, void *opaque, size_t size,
     VirtIOGPU *g = opaque;
     struct virtio_gpu_simple_resource *res;
     uint32_t resource_id, pformat;
-    void *bits = NULL;
     int i;
 
     g->hostmem = 0;
@@ -1311,24 +1291,17 @@ static int virtio_gpu_load(QEMUFile *f, void *opaque, size_t size,
         }
 
         res->hostmem = calc_image_hostmem(pformat, res->width, res->height);
-#ifdef WIN32
-        bits = qemu_win32_map_alloc(res->hostmem, &res->handle, &error_warn);
-        if (!bits) {
-            g_free(res);
-            return -EINVAL;
-        }
-#endif
-        res->image = pixman_image_create_bits(
-            pformat,
-            res->width, res->height,
-            bits, res->height ? res->hostmem / res->height : 0);
-        if (!res->image) {
+        if (!qemu_pixman_image_new_shareable(&res->image,
+                                             &res->share_handle,
+                                             "virtio-gpu res",
+                                             pformat,
+                                             res->width,
+                                             res->height,
+                                             res->height ? res->hostmem / res->height : 0,
+                                             &error_warn)) {
             g_free(res);
             return -EINVAL;
         }
-#ifdef WIN32
-        pixman_image_set_destroy_function(res->image, win32_pixman_image_destroy, res->handle);
-#endif
 
         res->addrs = g_new(uint64_t, res->iov_cnt);
         res->iov = g_new(struct iovec, res->iov_cnt);
@@ -1461,9 +1434,7 @@ static int virtio_gpu_post_load(void *opaque, int version_id)
                 return -EINVAL;
             }
             scanout->ds = qemu_create_displaysurface_pixman(res->image);
-#ifdef WIN32
-            qemu_displaysurface_win32_set_handle(scanout->ds, res->handle, 0);
-#endif
+            qemu_displaysurface_set_share_handle(scanout->ds, res->share_handle, 0);
             dpy_gfx_replace_surface(scanout->con, scanout->ds);
         }
 

include/hw/virtio/virtio-gpu.h

@@ -51,9 +51,7 @@ struct virtio_gpu_simple_resource {
     unsigned int iov_cnt;
     uint32_t scanout_bitmask;
     pixman_image_t *image;
-#ifdef WIN32
-    HANDLE handle;
-#endif
+    qemu_pixman_shareable share_handle;
     uint64_t hostmem;
 
     uint64_t blob_size;

include/ui/qemu-pixman.h

@@ -12,6 +12,8 @@
 #include "pixman-minimal.h"
 #endif
 
+#include "qapi/error.h"
+
 /*
  * pixman image formats are defined to be native endian,
  * that means host byte order on qemu.  So we go define
@@ -97,6 +99,28 @@ void qemu_pixman_glyph_render(pixman_image_t *glyph,
 
 void qemu_pixman_image_unref(pixman_image_t *image);
 
+#ifdef WIN32
+typedef HANDLE qemu_pixman_shareable;
+#define SHAREABLE_NONE (NULL)
+#define SHAREABLE_TO_PTR(handle) (handle)
+#define PTR_TO_SHAREABLE(ptr) (ptr)
+#else
+typedef int qemu_pixman_shareable;
+#define SHAREABLE_NONE (-1)
+#define SHAREABLE_TO_PTR(handle) GINT_TO_POINTER(handle)
+#define PTR_TO_SHAREABLE(ptr) GPOINTER_TO_INT(ptr)
+#endif
+
+bool qemu_pixman_image_new_shareable(
+    pixman_image_t **image,
+    qemu_pixman_shareable *handle,
+    const char *name,
+    pixman_format_code_t format,
+    int width,
+    int height,
+    int rowstride_bytes,
+    Error **errp);
+
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(pixman_image_t, qemu_pixman_image_unref)
 
 #endif /* QEMU_PIXMAN_H */

include/ui/surface.h

@@ -23,10 +23,8 @@ typedef struct DisplaySurface {
     GLenum gltype;
     GLuint texture;
 #endif
-#ifdef WIN32
-    HANDLE handle;
-    uint32_t handle_offset;
-#endif
+    qemu_pixman_shareable share_handle;
+    uint32_t share_handle_offset;
 } DisplaySurface;
 
 PixelFormat qemu_default_pixelformat(int bpp);
@@ -37,10 +35,10 @@ DisplaySurface *qemu_create_displaysurface_from(int width, int height,
 DisplaySurface *qemu_create_displaysurface_pixman(pixman_image_t *image);
 DisplaySurface *qemu_create_placeholder_surface(int w, int h,
                                                 const char *msg);
-#ifdef WIN32
-void qemu_displaysurface_win32_set_handle(DisplaySurface *surface,
-                                          HANDLE h, uint32_t offset);
-#endif
+
+void qemu_displaysurface_set_share_handle(DisplaySurface *surface,
+                                          qemu_pixman_shareable handle,
+                                          uint32_t offset);
 
 DisplaySurface *qemu_create_displaysurface(int width, int height);
 void qemu_free_displaysurface(DisplaySurface *surface);

meson.build

@@ -1037,7 +1037,7 @@ if not get_option('gio').auto() or have_system
     gio = not_found
   endif
   if gio.found()
-    gdbus_codegen = find_program(gio.get_variable('gdbus_codegen'),
+    gdbus_codegen = find_program('gdbus-codegen',
                                  required: get_option('gio'))
     gio_unix = dependency('gio-unix-2.0', required: get_option('gio'),
                           method: 'pkg-config')

tests/qtest/dbus-display-test.c

@@ -2,9 +2,14 @@
 #include "qemu/sockets.h"
 #include "qemu/dbus.h"
 #include "qemu/sockets.h"
+#include "glib.h"
+#include "glibconfig.h"
 #include <gio/gio.h>
 #include <gio/gunixfdlist.h>
 #include "libqtest.h"
+#ifndef WIN32
+#include <sys/mman.h>
+#endif
 #include "ui/dbus-display1.h"
 
 static GDBusConnection*
@@ -82,6 +87,7 @@ typedef struct TestDBusConsoleRegister {
     GThread *thread;
     GDBusConnection *listener_conn;
     GDBusObjectManagerServer *server;
+    bool with_map;
 } TestDBusConsoleRegister;
 
 static gboolean listener_handle_scanout(
@@ -94,13 +100,49 @@ static gboolean listener_handle_scanout(
     GVariant *arg_data,
     TestDBusConsoleRegister *test)
 {
+    if (!test->with_map) {
+        g_main_loop_quit(test->loop);
+    }
+
+    return DBUS_METHOD_INVOCATION_HANDLED;
+}
+
+#ifndef WIN32
+static gboolean listener_handle_scanout_map(
+    QemuDBusDisplay1ListenerUnixMap *object,
+    GDBusMethodInvocation *invocation,
+    GUnixFDList *fd_list,
+    GVariant *arg_handle,
+    guint arg_offset,
+    guint arg_width,
+    guint arg_height,
+    guint arg_stride,
+    guint arg_pixman_format,
+    TestDBusConsoleRegister *test)
+{
+    int fd = -1;
+    gint32 handle = g_variant_get_handle(arg_handle);
+    g_autoptr(GError) error = NULL;
+    void *addr = NULL;
+    size_t len = arg_height * arg_stride;
+
+    g_assert_cmpuint(g_unix_fd_list_get_length(fd_list), ==, 1);
+    fd = g_unix_fd_list_get(fd_list, handle, &error);
+    g_assert_no_error(error);
+
+    addr = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, arg_offset);
+    g_assert_no_errno(addr == MAP_FAILED ? -1 : 0);
+    g_assert_no_errno(munmap(addr, len));
+
     g_main_loop_quit(test->loop);
 
+    close(fd);
     return DBUS_METHOD_INVOCATION_HANDLED;
 }
+#endif
 
 static void
-test_dbus_console_setup_listener(TestDBusConsoleRegister *test)
+test_dbus_console_setup_listener(TestDBusConsoleRegister *test, bool with_map)
 {
     g_autoptr(GDBusObjectSkeleton) listener = NULL;
     g_autoptr(QemuDBusDisplay1ListenerSkeleton) iface = NULL;
@@ -114,6 +156,25 @@ test_dbus_console_setup_listener(TestDBusConsoleRegister *test)
                      NULL);
     g_dbus_object_skeleton_add_interface(listener,
                                          G_DBUS_INTERFACE_SKELETON(iface));
+    if (with_map) {
+#ifdef WIN32
+        g_test_skip("map test lacking on win32");
+        return;
+#else
+        g_autoptr(QemuDBusDisplay1ListenerUnixMapSkeleton) iface_map =
+            QEMU_DBUS_DISPLAY1_LISTENER_UNIX_MAP_SKELETON(
+                qemu_dbus_display1_listener_unix_map_skeleton_new());
+
+        g_object_connect(iface_map,
+                         "signal::handle-scanout-map", listener_handle_scanout_map, test,
+                         NULL);
+        g_dbus_object_skeleton_add_interface(listener,
+                                             G_DBUS_INTERFACE_SKELETON(iface_map));
+        g_object_set(iface, "interfaces",
+            (const gchar *[]) { "org.qemu.Display1.Listener.Unix.Map", NULL },
+            NULL);
+#endif
+    }
     g_dbus_object_manager_server_export(test->server, listener);
     g_dbus_object_manager_server_set_connection(test->server,
                                                 test->listener_conn);
@@ -145,7 +206,7 @@ test_dbus_console_registered(GObject *source_object,
     g_assert_no_error(err);
 
     test->listener_conn = g_thread_join(test->thread);
-    test_dbus_console_setup_listener(test);
+    test_dbus_console_setup_listener(test, test->with_map);
 }
 
 static gpointer
@@ -155,7 +216,7 @@ test_dbus_p2p_server_setup_thread(gpointer data)
 }
 
 static void
-test_dbus_display_console(void)
+test_dbus_display_console(const void* data)
 {
     g_autoptr(GError) err = NULL;
     g_autoptr(GDBusConnection) conn = NULL;
@@ -163,7 +224,7 @@ test_dbus_display_console(void)
     g_autoptr(GMainLoop) loop = NULL;
     QTestState *qts = NULL;
     int pair[2];
-    TestDBusConsoleRegister test = { 0, };
+    TestDBusConsoleRegister test = { 0, .with_map = GPOINTER_TO_INT(data) };
 #ifdef WIN32
     WSAPROTOCOL_INFOW info;
     g_autoptr(GVariant) listener = NULL;
@@ -299,7 +360,8 @@ main(int argc, char **argv)
     g_test_init(&argc, &argv, NULL);
 
     qtest_add_func("/dbus-display/vm", test_dbus_display_vm);
-    qtest_add_func("/dbus-display/console", test_dbus_display_console);
+    qtest_add_data_func("/dbus-display/console", GINT_TO_POINTER(false), test_dbus_display_console);
+    qtest_add_data_func("/dbus-display/console/map", GINT_TO_POINTER(true), test_dbus_display_console);
     qtest_add_func("/dbus-display/keyboard", test_dbus_display_keyboard);
 
     return g_test_run();

ui/console.c

@@ -37,6 +37,7 @@
 #include "trace.h"
 #include "exec/memory.h"
 #include "qom/object.h"
+#include "qemu/memfd.h"
 
 #include "console-priv.h"
 
@@ -452,60 +453,26 @@ qemu_graphic_console_init(Object *obj)
 {
 }
 
-#ifdef WIN32
-void qemu_displaysurface_win32_set_handle(DisplaySurface *surface,
-                                          HANDLE h, uint32_t offset)
+void qemu_displaysurface_set_share_handle(DisplaySurface *surface,
+                                          qemu_pixman_shareable handle,
+                                          uint32_t offset)
 {
-    assert(!surface->handle);
+    assert(surface->share_handle == SHAREABLE_NONE);
 
-    surface->handle = h;
-    surface->handle_offset = offset;
-}
-
-static void
-win32_pixman_image_destroy(pixman_image_t *image, void *data)
-{
-    DisplaySurface *surface = data;
-
-    if (!surface->handle) {
-        return;
-    }
-
-    assert(surface->handle_offset == 0);
+    surface->share_handle = handle;
+    surface->share_handle_offset = offset;
 
-    qemu_win32_map_free(
-        pixman_image_get_data(surface->image),
-        surface->handle,
-        &error_warn
-    );
 }
-#endif
 
 DisplaySurface *qemu_create_displaysurface(int width, int height)
 {
-    DisplaySurface *surface;
-    void *bits = NULL;
-#ifdef WIN32
-    HANDLE handle = NULL;
-#endif
-
     trace_displaysurface_create(width, height);
 
-#ifdef WIN32
-    bits = qemu_win32_map_alloc(width * height * 4, &handle, &error_abort);
-#endif
-
-    surface = qemu_create_displaysurface_from(
+    return qemu_create_displaysurface_from(
         width, height,
         PIXMAN_x8r8g8b8,
-        width * 4, bits
+        width * 4, NULL
     );
-    surface->flags = QEMU_ALLOCATED_FLAG;
-
-#ifdef WIN32
-    qemu_displaysurface_win32_set_handle(surface, handle, 0);
-#endif
-    return surface;
 }
 
 DisplaySurface *qemu_create_displaysurface_from(int width, int height,
@@ -515,15 +482,25 @@ DisplaySurface *qemu_create_displaysurface_from(int width, int height,
     DisplaySurface *surface = g_new0(DisplaySurface, 1);
 
     trace_displaysurface_create_from(surface, width, height, format);
-    surface->image = pixman_image_create_bits(format,
-                                              width, height,
-                                              (void *)data, linesize);
-    assert(surface->image != NULL);
-#ifdef WIN32
-    pixman_image_set_destroy_function(surface->image,
-                                      win32_pixman_image_destroy, surface);
-#endif
+    surface->share_handle = SHAREABLE_NONE;
+
+    if (data) {
+        surface->image = pixman_image_create_bits(format,
+                                                  width, height,
+                                                  (void *)data, linesize);
+    } else {
+        qemu_pixman_image_new_shareable(&surface->image,
+                                        &surface->share_handle,
+                                        "displaysurface",
+                                        format,
+                                        width,
+                                        height,
+                                        linesize,
+                                        &error_abort);
+        surface->flags = QEMU_ALLOCATED_FLAG;
+    }
 
+    assert(surface->image != NULL);
     return surface;
 }
 
@@ -532,6 +509,7 @@ DisplaySurface *qemu_create_displaysurface_pixman(pixman_image_t *image)
     DisplaySurface *surface = g_new0(DisplaySurface, 1);
 
     trace_displaysurface_create_pixman(surface);
+    surface->share_handle = SHAREABLE_NONE;
     surface->image = pixman_image_ref(image);
 
     return surface;

ui/dbus-console.c

@@ -41,7 +41,7 @@ struct _DBusDisplayConsole {
     DisplayChangeListener dcl;
 
     DBusDisplay *display;
-    GHashTable *listeners;
+    GPtrArray *listeners;
     QemuDBusDisplay1Console *iface;
 
     QemuDBusDisplay1Keyboard *iface_kbd;
@@ -142,8 +142,7 @@ dbus_display_console_init(DBusDisplayConsole *object)
 {
     DBusDisplayConsole *ddc = DBUS_DISPLAY_CONSOLE(object);
 
-    ddc->listeners = g_hash_table_new_full(g_str_hash, g_str_equal,
-                                            NULL, g_object_unref);
+    ddc->listeners = g_ptr_array_new_with_free_func(g_object_unref);
     ddc->dcl.ops = &dbus_console_dcl_ops;
 }
 
@@ -157,7 +156,7 @@ dbus_display_console_dispose(GObject *object)
     g_clear_object(&ddc->iface_mouse);
     g_clear_object(&ddc->iface_kbd);
     g_clear_object(&ddc->iface);
-    g_clear_pointer(&ddc->listeners, g_hash_table_unref);
+    g_clear_pointer(&ddc->listeners, g_ptr_array_unref);
     g_clear_pointer(&ddc->kbd, qkbd_state_free);
 
     G_OBJECT_CLASS(dbus_display_console_parent_class)->dispose(object);
@@ -179,7 +178,7 @@ listener_vanished_cb(DBusDisplayListener *listener)
 
     trace_dbus_listener_vanished(name);
 
-    g_hash_table_remove(ddc->listeners, name);
+    g_ptr_array_remove_fast(ddc->listeners, listener);
     qkbd_state_lift_all_keys(ddc->kbd);
 }
 
@@ -267,16 +266,6 @@ dbus_console_register_listener(DBusDisplayConsole *ddc,
     DBusDisplayListener *listener;
     int fd;
 
-    if (sender && g_hash_table_contains(ddc->listeners, sender)) {
-        g_dbus_method_invocation_return_error(
-            invocation,
-            DBUS_DISPLAY_ERROR,
-            DBUS_DISPLAY_ERROR_INVALID,
-            "`%s` is already registered!",
-            sender);
-        return DBUS_METHOD_INVOCATION_HANDLED;
-    }
-
 #ifdef G_OS_WIN32
     if (!dbus_win32_import_socket(invocation, arg_listener, &fd)) {
         return DBUS_METHOD_INVOCATION_HANDLED;
@@ -331,9 +320,7 @@ dbus_console_register_listener(DBusDisplayConsole *ddc,
         return DBUS_METHOD_INVOCATION_HANDLED;
     }
 
-    g_hash_table_insert(ddc->listeners,
-                        (gpointer)dbus_display_listener_get_bus_name(listener),
-                        listener);
+    g_ptr_array_add(ddc->listeners, listener);
     g_object_connect(listener_conn,
                      "swapped-signal::closed", listener_vanished_cb, listener,
                      NULL);

ui/dbus-display1.xml

@@ -469,6 +469,53 @@
     <property name="Interfaces" type="as" access="read"/>
   </interface>
 
+  <!--
+      org.qemu.Display1.Listener.Unix.Map:
+
+      This optional client-side interface can complement
+      org.qemu.Display1.Listener on ``/org/qemu/Display1/Listener`` for
+      Unix-specific shared memory scanouts.
+  -->
+  <?if $(env.HOST_OS) != windows?>
+  <interface name="org.qemu.Display1.Listener.Unix.Map">
+    <!--
+        ScanoutMap:
+        @handle: the shared map FD.
+        @offset: mapping offset, in bytes.
+        @width: display width, in pixels.
+        @height: display height, in pixels.
+        @stride: stride, in bytes.
+        @pixman_format: image format (ex: ``PIXMAN_X8R8G8B8``).
+
+        Resize and update the display content with a shared map.
+    -->
+    <method name="ScanoutMap">
+      <arg type="h" name="handle" direction="in"/>
+      <arg type="u" name="offset" direction="in"/>
+      <arg type="u" name="width" direction="in"/>
+      <arg type="u" name="height" direction="in"/>
+      <arg type="u" name="stride" direction="in"/>
+      <arg type="u" name="pixman_format" direction="in"/>
+    </method>
+
+    <!--
+        UpdateMap:
+        @x: the X update position, in pixels.
+        @y: the Y update position, in pixels.
+        @width: the update width, in pixels.
+        @height: the update height, in pixels.
+
+        Update the display content with the current shared map and the given region.
+    -->
+    <method name="UpdateMap">
+      <arg type="i" name="x" direction="in"/>
+      <arg type="i" name="y" direction="in"/>
+      <arg type="i" name="width" direction="in"/>
+      <arg type="i" name="height" direction="in"/>
+    </method>
+  </interface>
+  <?endif?>
+
   <!--
       org.qemu.Display1.Listener.Win32.Map:
 
@@ -476,6 +523,7 @@
       org.qemu.Display1.Listener on ``/org/qemu/Display1/Listener`` for Windows
       specific shared memory scanouts.
   -->
+  <?if $(env.HOST_OS) == windows?>
   <interface name="org.qemu.Display1.Listener.Win32.Map">
     <!--
         ScanoutMap:
@@ -513,6 +561,7 @@
       <arg type="i" name="height" direction="in"/>
     </method>
   </interface>
+  <?endif?>
 
   <!--
       org.qemu.Display1.Listener.Win32.D3d11:

ui/dbus-listener.c

@@ -26,6 +26,7 @@
 #include "qapi/error.h"
 #include "sysemu/sysemu.h"
 #include "dbus.h"
+#include "glib.h"
 #ifdef G_OS_UNIX
 #include <gio/gunixfdlist.h>
 #endif
@@ -82,10 +83,13 @@ struct _DBusDisplayListener {
 #ifdef CONFIG_OPENGL
     egl_fb fb;
 #endif
+#else /* !WIN32 */
+    QemuDBusDisplay1ListenerUnixMap *map_proxy;
 #endif
 
     guint dbus_filter;
-    guint32 out_serial_to_discard;
+    guint32 display_serial_to_discard;
+    guint32 cursor_serial_to_discard;
 };
 
 G_DEFINE_TYPE(DBusDisplayListener, dbus_display_listener, G_TYPE_OBJECT)
@@ -93,10 +97,20 @@ G_DEFINE_TYPE(DBusDisplayListener, dbus_display_listener, G_TYPE_OBJECT)
 static void dbus_gfx_update(DisplayChangeListener *dcl,
                             int x, int y, int w, int h);
 
-static void ddl_discard_pending_messages(DBusDisplayListener *ddl)
+static void ddl_discard_display_messages(DBusDisplayListener *ddl)
 {
-    ddl->out_serial_to_discard = g_dbus_connection_get_last_serial(
+    guint32 serial = g_dbus_connection_get_last_serial(
         g_dbus_proxy_get_connection(G_DBUS_PROXY(ddl->proxy)));
+
+    g_atomic_int_set(&ddl->display_serial_to_discard, serial);
+}
+
+static void ddl_discard_cursor_messages(DBusDisplayListener *ddl)
+{
+    guint32 serial = g_dbus_connection_get_last_serial(
+        g_dbus_proxy_get_connection(G_DBUS_PROXY(ddl->proxy)));
+
+    g_atomic_int_set(&ddl->cursor_serial_to_discard, serial);
 }
 
 #ifdef CONFIG_OPENGL
@@ -104,6 +118,8 @@ static void dbus_scanout_disable(DisplayChangeListener *dcl)
 {
     DBusDisplayListener *ddl = container_of(dcl, DBusDisplayListener, dcl);
 
+    ddl_discard_display_messages(ddl);
+
     qemu_dbus_display1_listener_call_disable(
         ddl->proxy, G_DBUS_CALL_FLAGS_NONE, -1, NULL, NULL, NULL);
 }
@@ -290,7 +306,7 @@ static void dbus_scanout_dmabuf(DisplayChangeListener *dcl,
         return;
     }
 
-    ddl_discard_pending_messages(ddl);
+    ddl_discard_display_messages(ddl);
 
     width = qemu_dmabuf_get_width(dmabuf);
     height = qemu_dmabuf_get_height(dmabuf);
@@ -320,13 +336,13 @@ static bool dbus_scanout_map(DBusDisplayListener *ddl)
         return true;
     }
 
-    if (!ddl->can_share_map || !ddl->ds->handle) {
+    if (!ddl->can_share_map || !ddl->ds->share_handle) {
         return false;
     }
 
     success = DuplicateHandle(
         GetCurrentProcess(),
-        ddl->ds->handle,
+        ddl->ds->share_handle,
         ddl->peer_process,
         &target_handle,
         FILE_MAP_READ | SECTION_QUERY,
@@ -338,12 +354,12 @@ static bool dbus_scanout_map(DBusDisplayListener *ddl)
         return false;
     }
 
-    ddl_discard_pending_messages(ddl);
+    ddl_discard_display_messages(ddl);
 
     if (!qemu_dbus_display1_listener_win32_map_call_scanout_map_sync(
             ddl->map_proxy,
             GPOINTER_TO_UINT(target_handle),
-            ddl->ds->handle_offset,
+            ddl->ds->share_handle_offset,
             surface_width(ddl->ds),
             surface_height(ddl->ds),
             surface_stride(ddl->ds),
@@ -401,7 +417,7 @@ dbus_scanout_share_d3d_texture(
         return false;
     }
 
-    ddl_discard_pending_messages(ddl);
+    ddl_discard_display_messages(ddl);
 
     qemu_dbus_display1_listener_win32_d3d11_call_scanout_texture2d(
         ddl->d3d11_proxy,
@@ -427,6 +443,51 @@ dbus_scanout_share_d3d_texture(
     return true;
 }
 #endif /* CONFIG_OPENGL */
+#else /* !WIN32 */
+static bool dbus_scanout_map(DBusDisplayListener *ddl)
+{
+    g_autoptr(GError) err = NULL;
+    g_autoptr(GUnixFDList) fd_list = NULL;
+
+    if (ddl->ds_share == SHARE_KIND_MAPPED) {
+        return true;
+    }
+
+    if (!ddl->can_share_map || ddl->ds->share_handle == SHAREABLE_NONE) {
+        return false;
+    }
+
+    ddl_discard_display_messages(ddl);
+    fd_list = g_unix_fd_list_new();
+    if (g_unix_fd_list_append(fd_list, ddl->ds->share_handle, &err) != 0) {
+        g_debug("Failed to setup scanout map fdlist: %s", err->message);
+        ddl->can_share_map = false;
+        return false;
+    }
+
+    if (!qemu_dbus_display1_listener_unix_map_call_scanout_map_sync(
+            ddl->map_proxy,
+            g_variant_new_handle(0),
+            ddl->ds->share_handle_offset,
+            surface_width(ddl->ds),
+            surface_height(ddl->ds),
+            surface_stride(ddl->ds),
+            surface_format(ddl->ds),
+            G_DBUS_CALL_FLAGS_NONE,
+            DBUS_DEFAULT_TIMEOUT,
+            fd_list,
+            NULL,
+            NULL,
+            &err)) {
+        g_debug("Failed to call ScanoutMap: %s", err->message);
+        ddl->can_share_map = false;
+        return false;
+    }
+
+    ddl->ds_share = SHARE_KIND_MAPPED;
+
+    return true;
+}
 #endif /* WIN32 */
 
 #ifdef CONFIG_OPENGL
@@ -497,6 +558,8 @@ static void dbus_cursor_dmabuf(DisplayChangeListener *dcl,
         return;
     }
 
+    ddl_discard_cursor_messages(ddl);
+
     egl_dmabuf_import_texture(dmabuf);
     texture = qemu_dmabuf_get_texture(dmabuf);
     if (!texture) {
@@ -659,7 +722,7 @@ static void ddl_scanout(DBusDisplayListener *ddl)
         surface_stride(ddl->ds) * surface_height(ddl->ds), TRUE,
         (GDestroyNotify)pixman_image_unref, pixman_image_ref(ddl->ds->image));
 
-    ddl_discard_pending_messages(ddl);
+    ddl_discard_display_messages(ddl);
 
     qemu_dbus_display1_listener_call_scanout(
         ddl->proxy, surface_width(ddl->ds), surface_height(ddl->ds),
@@ -677,16 +740,22 @@ static void dbus_gfx_update(DisplayChangeListener *dcl,
 
     trace_dbus_update(x, y, w, h);
 
-#ifdef WIN32
     if (dbus_scanout_map(ddl)) {
+#ifdef WIN32
         qemu_dbus_display1_listener_win32_map_call_update_map(
             ddl->map_proxy,
             x, y, w, h,
             G_DBUS_CALL_FLAGS_NONE,
             DBUS_DEFAULT_TIMEOUT, NULL, NULL, NULL);
+#else
+        qemu_dbus_display1_listener_unix_map_call_update_map(
+            ddl->map_proxy,
+            x, y, w, h,
+            G_DBUS_CALL_FLAGS_NONE,
+            DBUS_DEFAULT_TIMEOUT, NULL, NULL, NULL);
+#endif
         return;
     }
-#endif
 
     if (x == 0 && y == 0 && w == surface_width(ddl->ds) && h == surface_height(ddl->ds)) {
         return ddl_scanout(ddl);
@@ -740,6 +809,8 @@ static void dbus_cursor_define(DisplayChangeListener *dcl,
     DBusDisplayListener *ddl = container_of(dcl, DBusDisplayListener, dcl);
     GVariant *v_data = NULL;
 
+    ddl_discard_cursor_messages(ddl);
+
     v_data = g_variant_new_from_data(
         G_VARIANT_TYPE("ay"),
         c->data,
@@ -861,7 +932,6 @@ dbus_display_listener_get_console(DBusDisplayListener *ddl)
     return ddl->console;
 }
 
-#ifdef WIN32
 static bool
 dbus_display_listener_implements(DBusDisplayListener *ddl, const char *iface)
 {
@@ -876,6 +946,7 @@ dbus_display_listener_implements(DBusDisplayListener *ddl, const char *iface)
     return implements;
 }
 
+#ifdef WIN32
 static bool
 dbus_display_listener_setup_peer_process(DBusDisplayListener *ddl)
 {
@@ -958,10 +1029,11 @@ dbus_display_listener_setup_d3d11(DBusDisplayListener *ddl)
 static void
 dbus_display_listener_setup_shared_map(DBusDisplayListener *ddl)
 {
-#ifdef WIN32
     g_autoptr(GError) err = NULL;
 
-    if (!dbus_display_listener_implements(ddl, "org.qemu.Display1.Listener.Win32.Map")) {
+#ifdef WIN32
+    if (!dbus_display_listener_implements(
+            ddl, "org.qemu.Display1.Listener.Win32.Map")) {
         return;
     }
 
@@ -981,6 +1053,20 @@ dbus_display_listener_setup_shared_map(DBusDisplayListener *ddl)
         return;
     }
 
+    ddl->can_share_map = true;
+#else /* !WIN32 */
+    if (!dbus_display_listener_implements(
+            ddl, "org.qemu.Display1.Listener.Unix.Map")) {
+        return;
+    }
+    ddl->map_proxy = qemu_dbus_display1_listener_unix_map_proxy_new_sync(
+        ddl->conn, G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START, NULL,
+        "/org/qemu/Display1/Listener", NULL, &err);
+    if (!ddl->map_proxy) {
+        g_debug("Failed to setup Unix map proxy: %s", err->message);
+        return;
+    }
+
     ddl->can_share_map = true;
 #endif
 }
@@ -992,16 +1078,50 @@ dbus_filter(GDBusConnection *connection,
             gpointer         user_data)
 {
     DBusDisplayListener *ddl = DBUS_DISPLAY_LISTENER(user_data);
-    guint32 serial;
+    guint32 serial, discard_serial;
 
     if (incoming) {
         return message;
     }
 
     serial = g_dbus_message_get_serial(message);
-    if (serial <= ddl->out_serial_to_discard) {
-        trace_dbus_filter(serial, ddl->out_serial_to_discard);
-        return NULL;
+
+    discard_serial = g_atomic_int_get(&ddl->display_serial_to_discard);
+    if (serial <= discard_serial) {
+        const char *member = g_dbus_message_get_member(message);
+        static const char *const display_messages[] = {
+            "Scanout",
+            "Update",
+#ifdef CONFIG_GBM
+            "ScanoutDMABUF",
+            "UpdateDMABUF",
+#endif
+            "ScanoutMap",
+            "UpdateMap",
+            "Disable",
+            NULL,
+        };
+
+        if (g_strv_contains(display_messages, member)) {
+            trace_dbus_filter(serial, discard_serial);
+            g_object_unref(message);
+            return NULL;
+        }
+    }
+
+    discard_serial = g_atomic_int_get(&ddl->cursor_serial_to_discard);
+    if (serial <= discard_serial) {
+        const gchar *member = g_dbus_message_get_member(message);
+        static const char *const cursor_messages[] = {
+            "CursorDefine",
+            NULL
+        };
+
+        if (g_strv_contains(cursor_messages, member)) {
+            trace_dbus_filter(serial, discard_serial);
+            g_object_unref(message);
+            return NULL;
+        }
     }
 
     return message;
@@ -1037,6 +1157,7 @@ dbus_display_listener_new(const char *bus_name,
     ddl->console = console;
 
     dbus_display_listener_setup_shared_map(ddl);
+    trace_dbus_can_share_map(ddl->can_share_map);
     dbus_display_listener_setup_d3d11(ddl);
 
     con = qemu_console_lookup_by_index(dbus_display_console_get_index(console));

ui/qemu-pixman.c

@@ -4,7 +4,9 @@
  */
 
 #include "qemu/osdep.h"
+#include "qapi/error.h"
 #include "ui/console.h"
+#include "qemu/memfd.h"
 #include "standard-headers/drm/drm_fourcc.h"
 #include "trace.h"
 
@@ -267,3 +269,72 @@ void qemu_pixman_glyph_render(pixman_image_t *glyph,
     pixman_image_unref(ibg);
 }
 #endif /* CONFIG_PIXMAN */
+
+static void *
+qemu_pixman_shareable_alloc(const char *name, size_t size,
+                            qemu_pixman_shareable *handle,
+                            Error **errp)
+{
+#ifdef WIN32
+    return qemu_win32_map_alloc(size, handle, errp);
+#else
+    return qemu_memfd_alloc(name, size, 0, handle, errp);
+#endif
+}
+
+static void
+qemu_pixman_shareable_free(qemu_pixman_shareable handle,
+                           void *ptr, size_t size)
+{
+#ifdef WIN32
+    qemu_win32_map_free(ptr, handle, &error_warn);
+#else
+    qemu_memfd_free(ptr, size, handle);
+#endif
+}
+
+static void
+qemu_pixman_shared_image_destroy(pixman_image_t *image, void *data)
+{
+    qemu_pixman_shareable handle = PTR_TO_SHAREABLE(data);
+    void *ptr = pixman_image_get_data(image);
+    size_t size = pixman_image_get_height(image) * pixman_image_get_stride(image);
+
+    qemu_pixman_shareable_free(handle, ptr, size);
+}
+
+bool
+qemu_pixman_image_new_shareable(pixman_image_t **image,
+                                qemu_pixman_shareable *handle,
+                                const char *name,
+                                pixman_format_code_t format,
+                                int width,
+                                int height,
+                                int rowstride_bytes,
+                                Error **errp)
+{
+    ERRP_GUARD();
+    size_t size = height * rowstride_bytes;
+    void *bits = NULL;
+
+    g_return_val_if_fail(image != NULL, false);
+    g_return_val_if_fail(handle != NULL, false);
+
+    bits = qemu_pixman_shareable_alloc(name, size, handle, errp);
+    if (!bits) {
+        return false;
+    }
+
+    *image = pixman_image_create_bits(format, width, height, bits, rowstride_bytes);
+    if (!*image) {
+        error_setg(errp, "Failed to allocate image");
+        qemu_pixman_shareable_free(*handle, bits, size);
+        return false;
+    }
+
+    pixman_image_set_destroy_function(*image,
+                                      qemu_pixman_shared_image_destroy,
+                                      SHAREABLE_TO_PTR(*handle));
+
+    return true;
+}

ui/trace-events

@@ -166,6 +166,7 @@ dbus_clipboard_unregister(const char *bus_name) "peer %s"
 dbus_scanout_texture(uint32_t tex_id, bool backing_y_0_top, uint32_t backing_width, uint32_t backing_height, uint32_t x, uint32_t y, uint32_t w, uint32_t h) "tex_id:%u y0top:%d back:%ux%u %u+%u-%ux%u"
 dbus_gl_gfx_switch(void *p) "surf: %p"
 dbus_filter(unsigned int serial, unsigned int filter) "serial=%u (<= %u)"
+dbus_can_share_map(bool share) "can_share_map: %d"
 
 # egl-helpers.c
 egl_init_d3d11_device(void *p) "d3d device: %p"

util/memfd.c

@@ -28,6 +28,7 @@
 #include "qemu/osdep.h"
 
 #include "qapi/error.h"
+#include "qemu/error-report.h"
 #include "qemu/memfd.h"
 #include "qemu/host-utils.h"
 
@@ -149,11 +150,15 @@ err:
 void qemu_memfd_free(void *ptr, size_t size, int fd)
 {
     if (ptr) {
-        munmap(ptr, size);
+        if (munmap(ptr, size) != 0) {
+            error_report("memfd munmap() failed: %s", strerror(errno));
+        }
     }
 
     if (fd != -1) {
-        close(fd);
+        if (close(fd) != 0) {
+            error_report("memfd close() failed: %s", strerror(errno));
+        }
     }
 }