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, 16 insertions, 10 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
index 7d5ebb10323b..7971f57436dd 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
@@ -532,26 +532,32 @@ err_free_rk_obj:
 	return ERR_PTR(ret);
 }
 
-void *rockchip_gem_prime_vmap(struct drm_gem_object *obj)
+int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
 {
 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
 
-	if (rk_obj->pages)
-		return vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
-			    pgprot_writecombine(PAGE_KERNEL));
+	if (rk_obj->pages) {
+		void *vaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
+				  pgprot_writecombine(PAGE_KERNEL));
+		if (!vaddr)
+			return -ENOMEM;
+		dma_buf_map_set_vaddr(map, vaddr);
+		return 0;
+	}
 
 	if (rk_obj->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING)
-		return NULL;
+		return -ENOMEM;
+	dma_buf_map_set_vaddr(map, rk_obj->kvaddr);
 
-	return rk_obj->kvaddr;
+	return 0;
 }
 
-void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
+void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
 {
 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
 
 	if (rk_obj->pages) {
-		vunmap(vaddr);
+		vunmap(map->vaddr);
 		return;
 	}
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.h b/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
index 7ffc541bea07..5a70a56cd406 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
@@ -31,8 +31,8 @@ struct drm_gem_object *
 rockchip_gem_prime_import_sg_table(struct drm_device *dev,
 				   struct dma_buf_attachment *attach,
 				   struct sg_table *sg);
-void *rockchip_gem_prime_vmap(struct drm_gem_object *obj);
-void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
+int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
+void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
 
 /* drm driver mmap file operations */
 int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma);