drm/gem: Share code between drm_gem_fb_{begin,end}_cpu_access()

The error-recovery code in drm_gem_fb_begin() is of the same pattern
as drm_gem_fb_end(). Implement both of them using an internal helper.
No functional changes.

v2:
	* print additional information in error message (Javier)
	* fix commit description (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220517113327.26919-2-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index f4619803acd01e9635e1e1bae3376762235fb155..931828784dfe184d6dc66aebef5a8ce2e7e54211 100644 (file)
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -403,6 +403,28 @@ void drm_gem_fb_vunmap(struct drm_framebuffer *fb,
 }
 EXPORT_SYMBOL(drm_gem_fb_vunmap);
 
+static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir,
+                                       unsigned int num_planes)
+{
+       struct dma_buf_attachment *import_attach;
+       struct drm_gem_object *obj;
+       int ret;
+
+       while (num_planes) {
+               --num_planes;
+               obj = drm_gem_fb_get_obj(fb, num_planes);
+               if (!obj)
+                       continue;
+               import_attach = obj->import_attach;
+               if (!import_attach)
+                       continue;
+               ret = dma_buf_end_cpu_access(import_attach->dmabuf, dir);
+               if (ret)
+                       drm_err(fb->dev, "dma_buf_end_cpu_access(%u, %d) failed: %d\n",
+                               ret, num_planes, dir);
+       }
+}
+
 /**
  * drm_gem_fb_begin_cpu_access - prepares GEM buffer objects for CPU access
  * @fb: the framebuffer
@@ -422,7 +444,7 @@ int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direct
        struct dma_buf_attachment *import_attach;
        struct drm_gem_object *obj;
        size_t i;
-       int ret, ret2;
+       int ret;
 
        for (i = 0; i < ARRAY_SIZE(fb->obj); ++i) {
                obj = drm_gem_fb_get_obj(fb, i);
@@ -433,28 +455,13 @@ int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direct
                        continue;
                ret = dma_buf_begin_cpu_access(import_attach->dmabuf, dir);
                if (ret)
-                       goto err_dma_buf_end_cpu_access;
+                       goto err___drm_gem_fb_end_cpu_access;
        }
 
        return 0;
 
-err_dma_buf_end_cpu_access:
-       while (i) {
-               --i;
-               obj = drm_gem_fb_get_obj(fb, i);
-               if (!obj)
-                       continue;
-               import_attach = obj->import_attach;
-               if (!import_attach)
-                       continue;
-               ret2 = dma_buf_end_cpu_access(import_attach->dmabuf, dir);
-               if (ret2) {
-                       drm_err(fb->dev,
-                               "dma_buf_end_cpu_access() failed during error handling: %d\n",
-                               ret2);
-               }
-       }
-
+err___drm_gem_fb_end_cpu_access:
+       __drm_gem_fb_end_cpu_access(fb, dir, i);
        return ret;
 }
 EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access);
@@ -472,23 +479,7 @@ EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access);
  */
 void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir)
 {
-       size_t i = ARRAY_SIZE(fb->obj);
-       struct dma_buf_attachment *import_attach;
-       struct drm_gem_object *obj;
-       int ret;
-
-       while (i) {
-               --i;
-               obj = drm_gem_fb_get_obj(fb, i);
-               if (!obj)
-                       continue;
-               import_attach = obj->import_attach;
-               if (!import_attach)
-                       continue;
-               ret = dma_buf_end_cpu_access(import_attach->dmabuf, dir);
-               if (ret)
-                       drm_err(fb->dev, "dma_buf_end_cpu_access() failed: %d\n", ret);
-       }
+       __drm_gem_fb_end_cpu_access(fb, dir, ARRAY_SIZE(fb->obj));
 }
 EXPORT_SYMBOL(drm_gem_fb_end_cpu_access);