[PATCH v3 4/7] drm/gem: Update internal GEM vmap/vunmap interfaces to use struct dma_buf_map

Thomas Zimmermann
2020-09-29T15:15:01Z

GEM's vmap and vunmap interfaces now wrap memory pointers in struct
dma_buf_map.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/gpu/drm/drm_client.c | 18 +++++++++++-------
drivers/gpu/drm/drm_gem.c | 28 ++++++++++++++--------------
drivers/gpu/drm/drm_internal.h | 5 +++--
drivers/gpu/drm/drm_prime.c | 14 ++++----------
4 files changed, 32 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
index 495f47d23d87..ac0082bed966 100644
--- a/drivers/gpu/drm/drm_client.c
+++ b/drivers/gpu/drm/drm_client.c
@@ -3,6 +3,7 @@
* Copyright 2018 Noralf Trønnes
*/

+#include <linux/dma-buf-map.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
@@ -304,7 +305,8 @@ drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height, u
*/
void *drm_client_buffer_vmap(struct drm_client_buffer *buffer)
{
- void *vaddr;
+ struct dma_buf_map map;
+ int ret;

if (buffer->vaddr)
return buffer->vaddr;
@@ -317,13 +319,13 @@ void *drm_client_buffer_vmap(struct drm_client_buffer *buffer)
* fd_install step out of the driver backend hooks, to make that
* final step optional for internal users.
*/
- vaddr = drm_gem_vmap(buffer->gem);
- if (IS_ERR(vaddr))
- return vaddr;
+ ret = drm_gem_vmap(buffer->gem, &map);
+ if (ret)
+ return ERR_PTR(ret);

- buffer->vaddr = vaddr;
+ buffer->vaddr = map.vaddr;

- return vaddr;
+ return map.vaddr;
}
EXPORT_SYMBOL(drm_client_buffer_vmap);

@@ -337,7 +339,9 @@ EXPORT_SYMBOL(drm_client_buffer_vmap);
*/
void drm_client_buffer_vunmap(struct drm_client_buffer *buffer)
{
- drm_gem_vunmap(buffer->gem, buffer->vaddr);
+ struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(buffer->vaddr);
+
+ drm_gem_vunmap(buffer->gem, &map);
buffer->vaddr = NULL;
}
EXPORT_SYMBOL(drm_client_buffer_vunmap);
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 0c4a66dea5c2..f2b2f37d41c4 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -1205,32 +1205,32 @@ void drm_gem_unpin(struct drm_gem_object *obj)
obj->funcs->unpin(obj);
}

-void *drm_gem_vmap(struct drm_gem_object *obj)
+int drm_gem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
{
- struct dma_buf_map map;
int ret;

- if (!obj->funcs->vmap) {
- return ERR_PTR(-EOPNOTSUPP);
+ if (!obj->funcs->vmap)
+ return -EOPNOTSUPP;

- ret = obj->funcs->vmap(obj, &map);
+ 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 ret;
+ else if (dma_buf_map_is_null(map))
+ return -ENOMEM;

- return map.vaddr;
+ return 0;
}

-void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr)
+void drm_gem_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
{
- struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(vaddr);
-
- if (!vaddr)
+ if (dma_buf_map_is_null(map))
return;

if (obj->funcs->vunmap)
- obj->funcs->vunmap(obj, &map);
+ obj->funcs->vunmap(obj, map);
+
+ /* Always set the mapping to NULL. Callers may rely on this. */
+ dma_buf_map_clear(map);
}

/**
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index b65865c630b0..58832d75a9bd 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -33,6 +33,7 @@

struct dentry;
struct dma_buf;
+struct dma_buf_map;
struct drm_connector;
struct drm_crtc;
struct drm_framebuffer;
@@ -187,8 +188,8 @@ void drm_gem_print_info(struct drm_printer *p, unsigned int indent,

int drm_gem_pin(struct drm_gem_object *obj);
void drm_gem_unpin(struct drm_gem_object *obj);
-void *drm_gem_vmap(struct drm_gem_object *obj);
-void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr);
+int drm_gem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
+void drm_gem_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);

/* drm_debugfs.c drm_debugfs_crc.c */
#if defined(CONFIG_DEBUG_FS)
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 89e2a2496734..cb8fbeeb731b 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -667,21 +667,15 @@ EXPORT_SYMBOL(drm_gem_unmap_dma_buf);
*
* Sets up a kernel virtual mapping. This can be used as the &dma_buf_ops.vmap
* callback. Calls into &drm_gem_object_funcs.vmap for device specific handling.
+ * The kernel virtual address is returned in map.
*
- * Returns the kernel virtual address or NULL on failure.
+ * Returns 0 on success or a negative errno code otherwise.
*/
int drm_gem_dmabuf_vmap(struct dma_buf *dma_buf, struct dma_buf_map *map)
{
struct drm_gem_object *obj = dma_buf->priv;
- void *vaddr;

- vaddr = drm_gem_vmap(obj);
- if (IS_ERR(vaddr))
- return PTR_ERR(vaddr);
-
- dma_buf_map_set_vaddr(map, vaddr);
-
- return 0;
+ return drm_gem_vmap(obj, map);
}
EXPORT_SYMBOL(drm_gem_dmabuf_vmap);

@@ -697,7 +691,7 @@ void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, struct dma_buf_map *map)
{
struct drm_gem_object *obj = dma_buf->priv;

- drm_gem_vunmap(obj, map->vaddr);
+ drm_gem_vunmap(obj, map);
}
EXPORT_SYMBOL(drm_gem_dmabuf_vunmap);

--
2.28.0