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 <[email protected]> Acked-by: Christian König <[email protected]> Tested-by: Sam Ravnborg <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
LoveHeat · Nov 9, 2020 · 49a3f51 · 49a3f51
1 parent 4367660
commit 49a3f51
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Showing 49 changed files with 351 additions and 308 deletions.
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
@@ -450,6 +450,24 @@ Contact: Ville Syrjälä, Daniel Vetter
 
 Level: Intermediate
 
+Use struct dma_buf_map throughout codebase
+------------------------------------------
+
+Pointers to shared device memory are stored in struct dma_buf_map. Each
+instance knows whether it refers to system or I/O memory. Most of the DRM-wide
+interface have been converted to use struct dma_buf_map, but implementations
+often still use raw pointers.
+
+The task is to use struct dma_buf_map where it makes sense.
+
+* Memory managers should use struct dma_buf_map for dma-buf-imported buffers.
+* TTM might benefit from using struct dma_buf_map internally.
+* Framebuffer copying and blitting helpers should operate on struct dma_buf_map.
+
+Contact: Thomas Zimmermann <[email protected]>, Christian König, Daniel Vetter
+
+Level: Intermediate
+
 
 Core refactorings
 =================

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
@@ -232,6 +232,7 @@ config DRM_RADEON
 	select FW_LOADER
         select DRM_KMS_HELPER
         select DRM_TTM
+	select DRM_TTM_HELPER
 	select POWER_SUPPLY
 	select HWMON
 	select BACKLIGHT_CLASS_DEVICE
@@ -252,6 +253,7 @@ config DRM_AMDGPU
 	select DRM_KMS_HELPER
 	select DRM_SCHED
 	select DRM_TTM
+	select DRM_TTM_HELPER
 	select POWER_SUPPLY
 	select HWMON
 	select BACKLIGHT_CLASS_DEVICE

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -41,42 +41,6 @@
 #include <linux/dma-fence-array.h>
 #include <linux/pci-p2pdma.h>
 
-/**
- * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation
- * @obj: GEM BO
- *
- * Sets up an in-kernel virtual mapping of the BO's memory.
- *
- * Returns:
- * The virtual address of the mapping or an error pointer.
- */
-void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj)
-{
-	struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
-	int ret;
-
-	ret = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages,
-			  &bo->dma_buf_vmap);
-	if (ret)
-		return ERR_PTR(ret);
-
-	return bo->dma_buf_vmap.virtual;
-}
-
-/**
- * amdgpu_gem_prime_vunmap - &dma_buf_ops.vunmap implementation
- * @obj: GEM BO
- * @vaddr: Virtual address (unused)
- *
- * Tears down the in-kernel virtual mapping of the BO's memory.
- */
-void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
-{
-	struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
-
-	ttm_bo_kunmap(&bo->dma_buf_vmap);
-}
-
 /**
  * amdgpu_gem_prime_mmap - &drm_driver.gem_prime_mmap implementation
  * @obj: GEM BO

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h
@@ -31,8 +31,6 @@ struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev,
 					    struct dma_buf *dma_buf);
 bool amdgpu_dmabuf_is_xgmi_accessible(struct amdgpu_device *adev,
 				      struct amdgpu_bo *bo);
-void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj);
-void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
 int amdgpu_gem_prime_mmap(struct drm_gem_object *obj,
 			  struct vm_area_struct *vma);
 

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -33,6 +33,7 @@
 
 #include <drm/amdgpu_drm.h>
 #include <drm/drm_debugfs.h>
+#include <drm/drm_gem_ttm_helper.h>
 
 #include "amdgpu.h"
 #include "amdgpu_display.h"
@@ -220,8 +221,8 @@ static const struct drm_gem_object_funcs amdgpu_gem_object_funcs = {
 	.open = amdgpu_gem_object_open,
 	.close = amdgpu_gem_object_close,
 	.export = amdgpu_gem_prime_export,
-	.vmap = amdgpu_gem_prime_vmap,
-	.vunmap = amdgpu_gem_prime_vunmap,
+	.vmap = drm_gem_ttm_vmap,
+	.vunmap = drm_gem_ttm_vunmap,
 };
 
 /*

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
@@ -100,7 +100,6 @@ struct amdgpu_bo {
 	struct amdgpu_bo		*parent;
 	struct amdgpu_bo		*shadow;
 
-	struct ttm_bo_kmap_obj		dma_buf_vmap;
 	struct amdgpu_mn		*mn;
 
 

diff --git a/drivers/gpu/drm/ast/ast_cursor.c b/drivers/gpu/drm/ast/ast_cursor.c
@@ -39,7 +39,7 @@ static void ast_cursor_fini(struct ast_private *ast)
 
 	for (i = 0; i < ARRAY_SIZE(ast->cursor.gbo); ++i) {
 		gbo = ast->cursor.gbo[i];
-		drm_gem_vram_vunmap(gbo, ast->cursor.vaddr[i]);
+		drm_gem_vram_vunmap(gbo, &ast->cursor.map[i]);
 		drm_gem_vram_unpin(gbo);
 		drm_gem_vram_put(gbo);
 	}
@@ -60,7 +60,7 @@ int ast_cursor_init(struct ast_private *ast)
 	struct drm_device *dev = &ast->base;
 	size_t size, i;
 	struct drm_gem_vram_object *gbo;
-	void __iomem *vaddr;
+	struct dma_buf_map map;
 	int ret;
 
 	size = roundup(AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE, PAGE_SIZE);
@@ -77,16 +77,15 @@ int ast_cursor_init(struct ast_private *ast)
 			drm_gem_vram_put(gbo);
 			goto err_drm_gem_vram_put;
 		}
-		vaddr = drm_gem_vram_vmap(gbo);
-		if (IS_ERR(vaddr)) {
-			ret = PTR_ERR(vaddr);
+		ret = drm_gem_vram_vmap(gbo, &map);
+		if (ret) {
 			drm_gem_vram_unpin(gbo);
 			drm_gem_vram_put(gbo);
 			goto err_drm_gem_vram_put;
 		}
 
 		ast->cursor.gbo[i] = gbo;
-		ast->cursor.vaddr[i] = vaddr;
+		ast->cursor.map[i] = map;
 	}
 
 	return drmm_add_action_or_reset(dev, ast_cursor_release, NULL);
@@ -95,7 +94,7 @@ int ast_cursor_init(struct ast_private *ast)
 	while (i) {
 		--i;
 		gbo = ast->cursor.gbo[i];
-		drm_gem_vram_vunmap(gbo, ast->cursor.vaddr[i]);
+		drm_gem_vram_vunmap(gbo, &ast->cursor.map[i]);
 		drm_gem_vram_unpin(gbo);
 		drm_gem_vram_put(gbo);
 	}
@@ -170,6 +169,7 @@ int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb)
 {
 	struct drm_device *dev = &ast->base;
 	struct drm_gem_vram_object *gbo;
+	struct dma_buf_map map;
 	int ret;
 	void *src;
 	void __iomem *dst;
@@ -183,18 +183,17 @@ int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb)
 	ret = drm_gem_vram_pin(gbo, 0);
 	if (ret)
 		return ret;
-	src = drm_gem_vram_vmap(gbo);
-	if (IS_ERR(src)) {
-		ret = PTR_ERR(src);
+	ret = drm_gem_vram_vmap(gbo, &map);
+	if (ret)
 		goto err_drm_gem_vram_unpin;
-	}
+	src = map.vaddr; /* TODO: Use mapping abstraction properly */
 
-	dst = ast->cursor.vaddr[ast->cursor.next_index];
+	dst = ast->cursor.map[ast->cursor.next_index].vaddr_iomem;
 
 	/* do data transfer to cursor BO */
 	update_cursor_image(dst, src, fb->width, fb->height);
 
-	drm_gem_vram_vunmap(gbo, src);
+	drm_gem_vram_vunmap(gbo, &map);
 	drm_gem_vram_unpin(gbo);
 
 	return 0;
@@ -257,7 +256,7 @@ void ast_cursor_show(struct ast_private *ast, int x, int y,
 	u8 __iomem *sig;
 	u8 jreg;
 
-	dst = ast->cursor.vaddr[ast->cursor.next_index];
+	dst = ast->cursor.map[ast->cursor.next_index].vaddr;
 
 	sig = dst + AST_HWC_SIZE;
 	writel(x, sig + AST_HWC_SIGNATURE_X);

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
@@ -28,10 +28,11 @@
 #ifndef __AST_DRV_H__
 #define __AST_DRV_H__
 
-#include <linux/types.h>
-#include <linux/io.h>
+#include <linux/dma-buf-map.h>
 #include <linux/i2c.h>
 #include <linux/i2c-algo-bit.h>
+#include <linux/io.h>
+#include <linux/types.h>
 
 #include <drm/drm_connector.h>
 #include <drm/drm_crtc.h>
@@ -131,7 +132,7 @@ struct ast_private {
 
 	struct {
 		struct drm_gem_vram_object *gbo[AST_DEFAULT_HWC_NUM];
-		void __iomem *vaddr[AST_DEFAULT_HWC_NUM];
+		struct dma_buf_map map[AST_DEFAULT_HWC_NUM];
 		unsigned int next_index;
 	} cursor;
 

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
@@ -36,6 +36,7 @@
 #include <linux/pagemap.h>
 #include <linux/shmem_fs.h>
 #include <linux/dma-buf.h>
+#include <linux/dma-buf-map.h>
 #include <linux/mem_encrypt.h>
 #include <linux/pagevec.h>
 
@@ -1207,26 +1208,30 @@ void drm_gem_unpin(struct drm_gem_object *obj)
 
 void *drm_gem_vmap(struct drm_gem_object *obj)
 {
-	void *vaddr;
+	struct dma_buf_map map;
+	int ret;
 
-	if (obj->funcs->vmap)
-		vaddr = obj->funcs->vmap(obj);
-	else
-		vaddr = ERR_PTR(-EOPNOTSUPP);
+	if (!obj->funcs->vmap)
+		return ERR_PTR(-EOPNOTSUPP);
 
-	if (!vaddr)
-		vaddr = ERR_PTR(-ENOMEM);
+	ret = obj->funcs->vmap(obj, &map);
+	if (ret)
+		return ERR_PTR(ret);
+	else if (dma_buf_map_is_null(&map))
+		return ERR_PTR(-ENOMEM);
 
-	return vaddr;
+	return map.vaddr;
 }
 
 void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr)
 {
+	struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(vaddr);
+
 	if (!vaddr)
 		return;
 
 	if (obj->funcs->vunmap)
-		obj->funcs->vunmap(obj, vaddr);
+		obj->funcs->vunmap(obj, &map);
 }
 
 /**

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
  * drm_gem_cma_prime_vmap - map a CMA GEM object into the kernel's virtual
  *     address space
  * @obj: GEM object
+ * @map: Returns the kernel virtual address of the CMA GEM object's backing
+ *       store.
  *
  * This function maps a buffer exported via DRM PRIME into the kernel's
  * virtual address space. Since the CMA buffers are already mapped into the
@@ -527,13 +529,15 @@ EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
  * driver's &drm_gem_object_funcs.vmap callback.
  *
  * Returns:
- * The kernel virtual address of the CMA GEM object's backing store.
+ * 0 on success, or a negative error code otherwise.
  */
-void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj)
+int drm_gem_cma_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
 {
 	struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
 
-	return cma_obj->vaddr;
+	dma_buf_map_set_vaddr(map, cma_obj->vaddr);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);