drm: Replace drm_gem_vram_push_to_system() with kunmap + unpin

The push-to-system function forces a buffer out of video RAM. This decision
should rather be made by the memory manager. By replacing the function with
calls to the kunmap and unpin functions, the buffer's memory becomes available,
but the buffer remains in VRAM until it's evicted by a pin operation.

This patch replaces the remaining instances of drm_gem_vram_push_to_system()
in ast and mgag200, and removes the function from DRM.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20190521110831.20200-2-tzimmermann@suse.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 9aca9135a5ccb60dedb5c2f892f70a63e6f1cd27..fbafe39946549ff93c42a7f9fa3628cc5df7eda9 100644 (file)
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -521,7 +521,6 @@ static void ast_crtc_dpms(struct drm_crtc *crtc, int mode)
        }
 }
 
-/* ast is different - we will force move buffers out of VRAM */
 static int ast_crtc_do_set_base(struct drm_crtc *crtc,
                                struct drm_framebuffer *fb,
                                int x, int y, int atomic)
@@ -534,12 +533,15 @@ static int ast_crtc_do_set_base(struct drm_crtc *crtc,
        s64 gpu_addr;
        void *base;
 
-       /* push the previous fb to system ram */
        if (!atomic && fb) {
                ast_fb = to_ast_framebuffer(fb);
                obj = ast_fb->obj;
                gbo = drm_gem_vram_of_gem(obj);
-               drm_gem_vram_push_to_system(gbo);
+
+               /* unmap if console */
+               if (&ast->fbdev->afb == ast_fb)
+                       drm_gem_vram_kunmap(gbo);
+               drm_gem_vram_unpin(gbo);
        }
 
        ast_fb = to_ast_framebuffer(crtc->primary->fb);
@@ -622,11 +624,15 @@ static void ast_crtc_disable(struct drm_crtc *crtc)
        DRM_DEBUG_KMS("\n");
        ast_crtc_dpms(crtc, DRM_MODE_DPMS_OFF);
        if (crtc->primary->fb) {
+               struct ast_private *ast = crtc->dev->dev_private;
                struct ast_framebuffer *ast_fb = to_ast_framebuffer(crtc->primary->fb);
                struct drm_gem_object *obj = ast_fb->obj;
                struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(obj);
 
-               drm_gem_vram_push_to_system(gbo);
+               /* unmap if console */
+               if (&ast->fbdev->afb == ast_fb)
+                       drm_gem_vram_kunmap(gbo);
+               drm_gem_vram_unpin(gbo);
        }
        crtc->primary->fb = NULL;
 }

diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
index bde8237e80212bfba8212f80d0c71a7a63f2bfa3..b341b70832be18bda011869634ecf7442a719173 100644 (file)
--- a/drivers/gpu/drm/drm_gem_vram_helper.c
+++ b/drivers/gpu/drm/drm_gem_vram_helper.c
@@ -379,56 +379,6 @@ int drm_gem_vram_unpin_reserved(struct drm_gem_vram_object *gbo)
 }
 EXPORT_SYMBOL(drm_gem_vram_unpin_reserved);
 
-/**
- * drm_gem_vram_push_to_system() - \
-       Unpins a GEM VRAM object and moves it to system memory
- * @gbo:       the GEM VRAM object
- *
- * This operation only works if the caller holds the final pin on the
- * buffer object.
- *
- * Returns:
- * 0 on success, or
- * a negative error code otherwise.
- */
-int drm_gem_vram_push_to_system(struct drm_gem_vram_object *gbo)
-{
-       int i, ret;
-       struct ttm_operation_ctx ctx = { false, false };
-
-       ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
-       if (ret < 0)
-               return ret;
-
-       if (WARN_ON_ONCE(!gbo->pin_count))
-               goto out;
-
-       --gbo->pin_count;
-       if (gbo->pin_count)
-               goto out;
-
-       if (gbo->kmap.virtual)
-               ttm_bo_kunmap(&gbo->kmap);
-
-       drm_gem_vram_placement(gbo, TTM_PL_FLAG_SYSTEM);
-       for (i = 0; i < gbo->placement.num_placement ; ++i)
-               gbo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
-
-       ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
-       if (ret)
-               goto err_ttm_bo_unreserve;
-
-out:
-       ttm_bo_unreserve(&gbo->bo);
-
-       return 0;
-
-err_ttm_bo_unreserve:
-       ttm_bo_unreserve(&gbo->bo);
-       return ret;
-}
-EXPORT_SYMBOL(drm_gem_vram_push_to_system);
-
 /**
  * drm_gem_vram_kmap_at() - Maps a GEM VRAM object into kernel address space
  * @gbo:       the GEM VRAM object

diff --git a/drivers/gpu/drm/drm_vram_helper_common.c b/drivers/gpu/drm/drm_vram_helper_common.c
index 3b47f7002115b7eb44c18906ffc4144a20384af9..e9c9f9a80ba396c46c053cbb79e6fa43e183b53e 100644 (file)
--- a/drivers/gpu/drm/drm_vram_helper_common.c
+++ b/drivers/gpu/drm/drm_vram_helper_common.c
@@ -79,8 +79,6 @@
  * RAM. Call drm_gem_vram_pin() with &DRM_GEM_VRAM_PL_FLAG_VRAM or
  * &DRM_GEM_VRAM_PL_FLAG_SYSTEM to pin a buffer object in video RAM or system
  * memory. Call drm_gem_vram_unpin() to release the pinned object afterwards.
- * If you have to evict a buffer object from video RAM (e.g., for freeing up
- * memory), unpin the buffer and call drm_gem_vram_push_to_system().
  *
  * A buffer object that is pinned in video RAM has a fixed address within that
  * memory region. Call drm_gem_vram_offset() to retrieve this value. Typically

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index e79872c968bf64776742f5a4eea5cc64592a3c0d..1c8e0bfac015100b4c97f644a94dc1fc908af8f8 100644 (file)
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -858,8 +858,6 @@ static void mga_set_start_address(struct drm_crtc *crtc, unsigned offset)
        WREG_ECRT(0x0, ((u8)(addr >> 16) & 0xf) | crtcext0);
 }
 
-
-/* ast is different - we will force move buffers out of VRAM */
 static int mga_crtc_do_set_base(struct drm_crtc *crtc,
                                struct drm_framebuffer *fb,
                                int x, int y, int atomic)
@@ -872,12 +870,15 @@ static int mga_crtc_do_set_base(struct drm_crtc *crtc,
        s64 gpu_addr;
        void *base;
 
-       /* push the previous fb to system ram */
        if (!atomic && fb) {
                mga_fb = to_mga_framebuffer(fb);
                obj = mga_fb->obj;
                gbo = drm_gem_vram_of_gem(obj);
-               drm_gem_vram_push_to_system(gbo);
+
+               /* unmap if console */
+               if (&mdev->mfbdev->mfb == mga_fb)
+                       drm_gem_vram_kunmap(gbo);
+               drm_gem_vram_unpin(gbo);
        }
 
        mga_fb = to_mga_framebuffer(crtc->primary->fb);
@@ -1425,11 +1426,15 @@ static void mga_crtc_disable(struct drm_crtc *crtc)
        DRM_DEBUG_KMS("\n");
        mga_crtc_dpms(crtc, DRM_MODE_DPMS_OFF);
        if (crtc->primary->fb) {
+               struct mga_device *mdev = crtc->dev->dev_private;
                struct mga_framebuffer *mga_fb = to_mga_framebuffer(crtc->primary->fb);
                struct drm_gem_object *obj = mga_fb->obj;
                struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(obj);
 
-               drm_gem_vram_push_to_system(gbo);
+               /* unmap if console */
+               if (&mdev->mfbdev->mfb == mga_fb)
+                       drm_gem_vram_kunmap(gbo);
+               drm_gem_vram_unpin(gbo);
        }
        crtc->primary->fb = NULL;
 }

diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h
index ff1a817615436797d5ac228408fafa79d3511b5d..22e52d7dfbb7a7797df01f1d0165221d3c3eed2f 100644 (file)
--- a/include/drm/drm_gem_vram_helper.h
+++ b/include/drm/drm_gem_vram_helper.h
@@ -86,7 +86,6 @@ int drm_gem_vram_pin_reserved(struct drm_gem_vram_object *gbo,
                              unsigned long pl_flag);
 int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
 int drm_gem_vram_unpin_reserved(struct drm_gem_vram_object *gbo);
-int drm_gem_vram_push_to_system(struct drm_gem_vram_object *gbo);
 void *drm_gem_vram_kmap_at(struct drm_gem_vram_object *gbo, bool map,
                           bool *is_iomem, struct ttm_bo_kmap_obj *kmap);
 void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,