diff --git a/libweston/backend-drm/drm-gbm.c b/libweston/backend-drm/drm-gbm.c
index 30609e3e..4920b050 100644
--- a/libweston/backend-drm/drm-gbm.c
+++ b/libweston/backend-drm/drm-gbm.c
@@ -181,6 +181,10 @@ err:
 int
 drm_output_init_egl(struct drm_output *output, struct drm_backend *b)
 {
+	struct weston_drm_format *fmt;
+	const uint64_t *modifiers;
+	unsigned int num_modifiers;
+
 	uint32_t format[2] = {
 		output->gbm_format,
 		fallback_format_for(output->gbm_format),
@@ -191,30 +195,26 @@ drm_output_init_egl(struct drm_output *output, struct drm_backend *b)
 	};
 	struct weston_mode *mode = output->base.current_mode;
 	struct drm_plane *plane = output->scanout_plane;
-	unsigned int i;
 
 	assert(output->gbm_surface == NULL);
 
-	for (i = 0; i < plane->count_formats; i++) {
-		if (plane->formats[i].format == output->gbm_format)
-			break;
-	}
-
-	if (i == plane->count_formats) {
+	fmt = weston_drm_format_array_find_format(&plane->formats, output->gbm_format);
+	if (!fmt) {
 		weston_log("format 0x%x not supported by output %s\n",
 			   output->gbm_format, output->base.name);
 		return -1;
 	}
 
 #ifdef HAVE_GBM_MODIFIERS
-	if (plane->formats[i].count_modifiers > 0) {
+	modifiers = weston_drm_format_get_modifiers(fmt, &num_modifiers);
+	if (num_modifiers > 0) {
 		output->gbm_surface =
 			gbm_surface_create_with_modifiers(b->gbm,
 							  mode->width,
 							  mode->height,
 							  output->gbm_format,
-							  plane->formats[i].modifiers,
-							  plane->formats[i].count_modifiers);
+							  modifiers,
+							  num_modifiers);
 	}
 
 	/* If allocating with modifiers fails, try again without. This can
diff --git a/libweston/backend-drm/drm-internal.h b/libweston/backend-drm/drm-internal.h
index 74d6c7fb..3e20c781 100644
--- a/libweston/backend-drm/drm-internal.h
+++ b/libweston/backend-drm/drm-internal.h
@@ -435,7 +435,6 @@ struct drm_plane {
 
 	uint32_t possible_crtcs;
 	uint32_t plane_id;
-	uint32_t count_formats;
 
 	struct drm_property_info props[WDRM_PLANE__COUNT];
 
@@ -447,11 +446,7 @@ struct drm_plane {
 
 	struct wl_list link;
 
-	struct {
-		uint32_t format;
-		uint32_t count_modifiers;
-		uint64_t *modifiers;
-	} formats[];
+	struct weston_drm_format_array formats;
 };
 
 struct drm_connector {
diff --git a/libweston/backend-drm/drm-virtual.c b/libweston/backend-drm/drm-virtual.c
index 5ef5f8a7..d016d6ba 100644
--- a/libweston/backend-drm/drm-virtual.c
+++ b/libweston/backend-drm/drm-virtual.c
@@ -93,9 +93,10 @@ static struct drm_plane *
 drm_virtual_plane_create(struct drm_backend *b, struct drm_output *output)
 {
 	struct drm_plane *plane;
+	struct weston_drm_format *fmt;
+	int ret;
 
-	/* num of formats is one */
-	plane = zalloc(sizeof(*plane) + sizeof(plane->formats[0]));
+	plane = zalloc(sizeof(*plane));
 	if (!plane) {
 		weston_log("%s: out of memory\n", __func__);
 		return NULL;
@@ -105,21 +106,28 @@ drm_virtual_plane_create(struct drm_backend *b, struct drm_output *output)
 	plane->backend = b;
 	plane->state_cur = drm_plane_state_alloc(NULL, plane);
 	plane->state_cur->complete = true;
-	plane->formats[0].format = output->gbm_format;
-	plane->count_formats = 1;
+
+	weston_drm_format_array_init(&plane->formats);
+	fmt = weston_drm_format_array_add_format(&plane->formats, output->gbm_format);
+	if (!fmt)
+		goto err;
+
 	if ((output->gbm_bo_flags & GBM_BO_USE_LINEAR) && b->fb_modifiers) {
-		uint64_t *modifiers = zalloc(sizeof *modifiers);
-		if (modifiers) {
-			*modifiers = DRM_FORMAT_MOD_LINEAR;
-			plane->formats[0].modifiers = modifiers;
-			plane->formats[0].count_modifiers = 1;
-		}
+		ret = weston_drm_format_add_modifier(fmt, DRM_FORMAT_MOD_LINEAR);
+		if (ret < 0)
+			goto err;
 	}
 
 	weston_plane_init(&plane->base, b->compositor, 0, 0);
 	wl_list_insert(&b->plane_list, &plane->link);
 
 	return plane;
+
+err:
+	drm_plane_state_free(plane->state_cur, true);
+	weston_drm_format_array_fini(&plane->formats);
+	free(plane);
+	return NULL;
 }
 
 /**
@@ -133,8 +141,7 @@ drm_virtual_plane_destroy(struct drm_plane *plane)
 	drm_plane_state_free(plane->state_cur, true);
 	weston_plane_release(&plane->base);
 	wl_list_remove(&plane->link);
-	if (plane->formats[0].modifiers)
-		free(plane->formats[0].modifiers);
+	weston_drm_format_array_fini(&plane->formats);
 	free(plane);
 }
 
diff --git a/libweston/backend-drm/drm.c b/libweston/backend-drm/drm.c
index 82f6ee29..d3c178bf 100644
--- a/libweston/backend-drm/drm.c
+++ b/libweston/backend-drm/drm.c
@@ -760,20 +760,19 @@ drm_plane_create(struct drm_backend *b, const drmModePlane *kplane,
 	struct drm_plane *plane;
 	drmModeObjectProperties *props;
 	uint64_t *zpos_range_values;
-	uint32_t num_formats = (kplane) ? kplane->count_formats : 1;
 
-	plane = zalloc(sizeof(*plane) +
-		       (sizeof(plane->formats[0]) * num_formats));
+	plane = zalloc(sizeof(*plane));
 	if (!plane) {
 		weston_log("%s: out of memory\n", __func__);
 		return NULL;
 	}
 
 	plane->backend = b;
-	plane->count_formats = num_formats;
 	plane->state_cur = drm_plane_state_alloc(NULL, plane);
 	plane->state_cur->complete = true;
 
+	weston_drm_format_array_init(&plane->formats);
+
 	if (kplane) {
 		plane->possible_crtcs = kplane->possible_crtcs;
 		plane->plane_id = kplane->plane_id;
@@ -814,11 +813,11 @@ drm_plane_create(struct drm_backend *b, const drmModePlane *kplane,
 	else {
 		plane->possible_crtcs = (1 << output->crtc->pipe);
 		plane->plane_id = 0;
-		plane->count_formats = 1;
-		plane->formats[0].format = format;
 		plane->type = type;
 		plane->zpos_max = DRM_PLANE_ZPOS_INVALID_PLANE;
 		plane->zpos_min = DRM_PLANE_ZPOS_INVALID_PLANE;
+		if (!weston_drm_format_array_add_format(&plane->formats, format))
+			goto err;
 	}
 
 	if (plane->type == WDRM_PLANE_TYPE__COUNT)
@@ -845,6 +844,7 @@ drm_plane_create(struct drm_backend *b, const drmModePlane *kplane,
 err_props:
 	drm_property_info_free(plane->props, WDRM_PLANE__COUNT);
 err:
+	weston_drm_format_array_fini(&plane->formats);
 	drm_plane_state_free(plane->state_cur, true);
 	free(plane);
 	return NULL;
@@ -945,6 +945,7 @@ drm_plane_destroy(struct drm_plane *plane)
 	drm_plane_state_free(plane->state_cur, true);
 	drm_property_info_free(plane->props, WDRM_PLANE__COUNT);
 	weston_plane_release(&plane->base);
+	weston_drm_format_array_fini(&plane->formats);
 	wl_list_remove(&plane->link);
 	free(plane);
 }
diff --git a/libweston/backend-drm/kms.c b/libweston/backend-drm/kms.c
index f0f85266..75730ffe 100644
--- a/libweston/backend-drm/kms.c
+++ b/libweston/backend-drm/kms.c
@@ -433,12 +433,14 @@ drm_plane_populate_formats(struct drm_plane *plane, const drmModePlane *kplane,
 			   const drmModeObjectProperties *props,
 			   const bool use_modifiers)
 {
-	unsigned i;
-	drmModePropertyBlobRes *blob;
+	unsigned i, j;
+	drmModePropertyBlobRes *blob = NULL;
 	struct drm_format_modifier_blob *fmt_mod_blob;
 	struct drm_format_modifier *blob_modifiers;
 	uint32_t *blob_formats;
 	uint32_t blob_id;
+	struct weston_drm_format *fmt;
+	int ret = 0;
 
 	if (!use_modifiers)
 		goto fallback;
@@ -457,20 +459,15 @@ drm_plane_populate_formats(struct drm_plane *plane, const drmModePlane *kplane,
 	blob_formats = formats_ptr(fmt_mod_blob);
 	blob_modifiers = modifiers_ptr(fmt_mod_blob);
 
-	if (plane->count_formats != fmt_mod_blob->count_formats) {
-		weston_log("DRM backend: format count differs between "
-		           "plane (%d) and IN_FORMATS (%d)\n",
-			   plane->count_formats,
-			   fmt_mod_blob->count_formats);
-		weston_log("This represents a kernel bug; Weston is "
-			   "unable to continue.\n");
-		abort();
-	}
+	assert(kplane->count_formats == fmt_mod_blob->count_formats);
 
 	for (i = 0; i < fmt_mod_blob->count_formats; i++) {
-		uint32_t count_modifiers = 0;
-		uint64_t *modifiers = NULL;
-		unsigned j;
+		fmt = weston_drm_format_array_add_format(&plane->formats,
+							 blob_formats[i]);
+		if (!fmt) {
+			ret = -1;
+			goto out;
+		}
 
 		for (j = 0; j < fmt_mod_blob->count_modifiers; j++) {
 			struct drm_format_modifier *mod = &blob_modifiers[j];
@@ -480,38 +477,33 @@ drm_plane_populate_formats(struct drm_plane *plane, const drmModePlane *kplane,
 			if (!(mod->formats & (1 << (i - mod->offset))))
 				continue;
 
-			modifiers = realloc(modifiers,
-					    (count_modifiers + 1) *
-					     sizeof(modifiers[0]));
-			assert(modifiers);
-			modifiers[count_modifiers++] = mod->modifier;
+			ret = weston_drm_format_add_modifier(fmt, mod->modifier);
+			if (ret < 0)
+				goto out;
 		}
 
-		if (count_modifiers == 0) {
-			modifiers = malloc(sizeof(*modifiers));
-			*modifiers = DRM_FORMAT_MOD_LINEAR;
-			count_modifiers = 1;
+		if (fmt->modifiers.size == 0) {
+			ret = weston_drm_format_add_modifier(fmt, DRM_FORMAT_MOD_LINEAR);
+			if (ret < 0)
+				goto out;
 		}
-
-		plane->formats[i].format = blob_formats[i];
-		plane->formats[i].modifiers = modifiers;
-		plane->formats[i].count_modifiers = count_modifiers;
 	}
 
+out:
 	drmModeFreePropertyBlob(blob);
-
-	return 0;
+	return ret;
 
 fallback:
 	/* No IN_FORMATS blob available, so just use the old. */
-	assert(plane->count_formats == kplane->count_formats);
 	for (i = 0; i < kplane->count_formats; i++) {
-		plane->formats[i].format = kplane->formats[i];
-		plane->formats[i].modifiers = malloc(sizeof(uint64_t));
-		plane->formats[i].modifiers[0] = DRM_FORMAT_MOD_LINEAR;
-		plane->formats[i].count_modifiers = 1;
+		fmt = weston_drm_format_array_add_format(&plane->formats,
+							 kplane->formats[i]);
+		if (!fmt)
+			return -1;
+		ret = weston_drm_format_add_modifier(fmt, DRM_FORMAT_MOD_LINEAR);
+		if (ret < 0)
+			return -1;
 	}
-
 	return 0;
 }
 
diff --git a/libweston/backend-drm/state-propose.c b/libweston/backend-drm/state-propose.c
index 5eda8648..cafc0d9e 100644
--- a/libweston/backend-drm/state-propose.c
+++ b/libweston/backend-drm/state-propose.c
@@ -129,25 +129,19 @@ drm_output_plane_has_valid_format(struct drm_plane *plane,
 				  struct drm_fb *fb)
 {
 	struct drm_backend *b = plane->backend;
-	unsigned int i;
+	struct weston_drm_format *fmt;
 
 	if (!fb)
 		return false;
 
 	/* Check whether the format is supported */
-	for (i = 0; i < plane->count_formats; i++) {
-		unsigned int j;
-
-		if (plane->formats[i].format != fb->format->format)
-			continue;
-
+	fmt = weston_drm_format_array_find_format(&plane->formats,
+						  fb->format->format);
+	if (fmt) {
 		if (fb->modifier == DRM_FORMAT_MOD_INVALID)
 			return true;
-
-		for (j = 0; j < plane->formats[i].count_modifiers; j++) {
-			if (plane->formats[i].modifiers[j] == fb->modifier)
-				return true;
-		}
+		if (weston_drm_format_has_modifier(fmt, fb->modifier))
+			return true;
 	}
 
 	drm_debug(b, "\t\t\t\t[%s] not placing view on %s: "