drm/gem: Use struct dma_buf_map in GEM vmap ops and convert GEM backends

This patch replaces the vmap/vunmap's use of raw pointers in GEM object
functions with instances of struct dma_buf_map. GEM backends are
converted as well. For most of them, this simply changes the returned type.

TTM-based drivers now return information about the location of the memory,
either system or I/O memory. GEM VRAM helpers and qxl now use ttm_bo_vmap()
et al. Amdgpu, nouveau and radeon use drm_gem_ttm_vmap() et al instead of
implementing their own vmap callbacks.

v7:
	* init QXL cursor to mapped BO buffer (kernel test robot)
v5:
	* update vkms after switch to shmem
v4:
	* use ttm_bo_vmap(), drm_gem_ttm_vmap(), et al. (Daniel, Christian)
	* fix a trailing { in drm_gem_vmap()
	* remove several empty functions instead of converting them (Daniel)
	* comment uses of raw pointers with a TODO (Daniel)
	* TODO list: convert more helpers to use struct dma_buf_map

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Christian König <christian.koenig@amd.com>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-7-tzimmermann@suse.de

2 files changed, 24 insertions, 13 deletions

diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 9890137bcb8d..0824327cc860 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0+
 
+#include <linux/dma-buf-map.h>
+
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_fourcc.h>
@@ -146,15 +148,16 @@ static int vkms_prepare_fb(struct drm_plane *plane,
 			   struct drm_plane_state *state)
 {
 	struct drm_gem_object *gem_obj;
-	void *vaddr;
+	struct dma_buf_map map;
+	int ret;
 
 	if (!state->fb)
 		return 0;
 
 	gem_obj = drm_gem_fb_get_obj(state->fb, 0);
-	vaddr = drm_gem_shmem_vmap(gem_obj);
-	if (IS_ERR(vaddr))
-		DRM_ERROR("vmap failed: %li\n", PTR_ERR(vaddr));
+	ret = drm_gem_shmem_vmap(gem_obj, &map);
+	if (ret)
+		DRM_ERROR("vmap failed: %d\n", ret);
 
 	return drm_gem_fb_prepare_fb(plane, state);
 }
@@ -164,13 +167,15 @@ static void vkms_cleanup_fb(struct drm_plane *plane,
 {
 	struct drm_gem_object *gem_obj;
 	struct drm_gem_shmem_object *shmem_obj;
+	struct dma_buf_map map;
 
 	if (!old_state->fb)
 		return;
 
 	gem_obj = drm_gem_fb_get_obj(old_state->fb, 0);
 	shmem_obj = to_drm_gem_shmem_obj(drm_gem_fb_get_obj(old_state->fb, 0));
-	drm_gem_shmem_vunmap(gem_obj, shmem_obj->vaddr);
+	dma_buf_map_set_vaddr(&map, shmem_obj->vaddr);
+	drm_gem_shmem_vunmap(gem_obj, &map);
 }
 
 static const struct drm_plane_helper_funcs vkms_primary_helper_funcs = {
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 26b903926872..67f80ab1e85f 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0+
 
-#include "vkms_drv.h"
+#include <linux/dma-buf-map.h>
+
 #include <drm/drm_fourcc.h>
 #include <drm/drm_writeback.h>
 #include <drm/drm_probe_helper.h>
@@ -8,6 +9,8 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_shmem_helper.h>
 
+#include "vkms_drv.h"
+
 static const u32 vkms_wb_formats[] = {
 	DRM_FORMAT_XRGB8888,
 };
@@ -65,19 +68,20 @@ static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector,
 			       struct drm_writeback_job *job)
 {
 	struct drm_gem_object *gem_obj;
-	void *vaddr;
+	struct dma_buf_map map;
+	int ret;
 
 	if (!job->fb)
 		return 0;
 
 	gem_obj = drm_gem_fb_get_obj(job->fb, 0);
-	vaddr = drm_gem_shmem_vmap(gem_obj);
-	if (IS_ERR(vaddr)) {
-		DRM_ERROR("vmap failed: %li\n", PTR_ERR(vaddr));
-		return PTR_ERR(vaddr);
+	ret = drm_gem_shmem_vmap(gem_obj, &map);
+	if (ret) {
+		DRM_ERROR("vmap failed: %d\n", ret);
+		return ret;
 	}
 
-	job->priv = vaddr;
+	job->priv = map.vaddr;
 
 	return 0;
 }
@@ -87,12 +91,14 @@ static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
 {
 	struct drm_gem_object *gem_obj;
 	struct vkms_device *vkmsdev;
+	struct dma_buf_map map;
 
 	if (!job->fb)
 		return;
 
 	gem_obj = drm_gem_fb_get_obj(job->fb, 0);
-	drm_gem_shmem_vunmap(gem_obj, job->priv);
+	dma_buf_map_set_vaddr(&map, job->priv);
+	drm_gem_shmem_vunmap(gem_obj, &map);
 
 	vkmsdev = drm_device_to_vkms_device(gem_obj->dev);
 	vkms_set_composer(&vkmsdev->output, false);