[PATCH 1/3] drm/ttm: Provide struct ttm_global for referencing TTM global state

Fri Oct 19 03:30:26 UTC 2018

On Fri, Oct 19, 2018 at 12:27:50AM +0800, Thomas Zimmermann wrote:
> The new struct ttm_global provides drivers with TTM's global memory and
> BO in a unified way. Initialization and release is handled internally.
> 
> The functionality provided by struct ttm_global is currently re-implemented
> by a dozen individual DRM drivers using struct drm_global. The implementation
> of struct ttm_global is also built on top of drm_global, so it can co-exists
> with the existing drivers. Once all TTM-based drivers have been converted to
> struct ttm_global, the implementation of struct drm_global can be made
> private to TTM.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
> ---
>  drivers/gpu/drm/ttm/Makefile     |  2 +-
>  drivers/gpu/drm/ttm/ttm_global.c | 98 ++++++++++++++++++++++++++++++++
>  include/drm/drm_global.h         |  8 +++
>  include/drm/ttm/ttm_global.h     | 79 +++++++++++++++++++++++++
>  4 files changed, 186 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/ttm/ttm_global.c
>  create mode 100644 include/drm/ttm/ttm_global.h
> 
> diff --git a/drivers/gpu/drm/ttm/Makefile b/drivers/gpu/drm/ttm/Makefile
> index 01fc670ce7a2..b7272b26e9f3 100644
> --- a/drivers/gpu/drm/ttm/Makefile
> +++ b/drivers/gpu/drm/ttm/Makefile
> @@ -5,7 +5,7 @@
>  ttm-y := ttm_memory.o ttm_tt.o ttm_bo.o \
>  	ttm_bo_util.o ttm_bo_vm.o ttm_module.o \
>  	ttm_execbuf_util.o ttm_page_alloc.o ttm_bo_manager.o \
> -	ttm_page_alloc_dma.o
> +	ttm_page_alloc_dma.o ttm_global.o
>  ttm-$(CONFIG_AGP) += ttm_agp_backend.o
>  
>  obj-$(CONFIG_DRM_TTM) += ttm.o
> diff --git a/drivers/gpu/drm/ttm/ttm_global.c b/drivers/gpu/drm/ttm/ttm_global.c
> new file mode 100644
> index 000000000000..ca9da0a46147
> --- /dev/null
> +++ b/drivers/gpu/drm/ttm/ttm_global.c
> @@ -0,0 +1,98 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
> +/**************************************************************************
> + *
> + * Copyright 2008-2009 VMware, Inc., Palo Alto, CA., USA
> + * All Rights Reserved.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the
> + * "Software"), to deal in the Software without restriction, including
> + * without limitation the rights to use, copy, modify, merge, publish,
> + * distribute, sub license, and/or sell copies of the Software, and to
> + * permit persons to whom the Software is furnished to do so, subject to
> + * the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the
> + * next paragraph) shall be included in all copies or substantial portions
> + * of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
> + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
> + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
> + * USE OR OTHER DEALINGS IN THE SOFTWARE.
> + *
> + **************************************************************************/
> +
> +#include <drm/ttm/ttm_global.h>
> +#include <drm/ttm/ttm_bo_driver.h>
> +#include <drm/ttm/ttm_memory.h>
> +#include <linux/kernel.h>
> +
> +static int ttm_global_init_mem(struct drm_global_reference *ref)
> +{
> +	BUG_ON(!ref->object);
> +	return ttm_mem_global_init(ref->object);
> +}
> +
> +static void ttm_global_release_mem(struct drm_global_reference *ref)
> +{
> +	BUG_ON(!ref->object);
> +	ttm_mem_global_release(ref->object);
> +}
> +
> +static int ttm_global_init_bo(struct drm_global_reference *ref)
> +{
> +	struct ttm_global *glob =
> +		container_of(ref, struct ttm_global, bo_ref);
> +	BUG_ON(!ref->object);
> +	BUG_ON(!glob->mem_ref.object);
> +	return ttm_bo_global_init(ref->object, glob->mem_ref.object);
> +}
> +
> +static void ttm_global_release_bo(struct drm_global_reference *ref)
> +{
> +	BUG_ON(!ref->object);
> +	ttm_bo_global_release(ref->object);
> +}
> +
> +int ttm_global_init(struct ttm_global *glob)
> +{
> +	int ret;
> +

We would better add a protection here to make sure the glob is not NULL.

if (!glob)
        return -EINVAL;

Others, look good for me.

Thanks,
Ray

> +	glob->mem_ref.global_type = DRM_GLOBAL_TTM_MEM;
> +	glob->mem_ref.size = sizeof(struct ttm_mem_global);
> +	glob->bo_ref.object = NULL;
> +	glob->mem_ref.init = &ttm_global_init_mem;
> +	glob->mem_ref.release = &ttm_global_release_mem;
> +	ret = drm_global_item_ref(&glob->mem_ref);
> +	if (ret)
> +		return ret;
> +
> +	glob->bo_ref.global_type = DRM_GLOBAL_TTM_BO;
> +	glob->bo_ref.size = sizeof(struct ttm_bo_global);
> +	glob->bo_ref.object = NULL;
> +	glob->bo_ref.init = &ttm_global_init_bo;
> +	glob->bo_ref.release = &ttm_global_release_bo;
> +	ret = drm_global_item_ref(&glob->bo_ref);
> +	if (ret)
> +		goto err_drm_global_item_unref_mem;
> +
> +	return 0;
> +
> +err_drm_global_item_unref_mem:
> +	drm_global_item_unref(&glob->mem_ref);
> +	return ret;
> +}
> +
> +EXPORT_SYMBOL(ttm_global_init);
> +
> +void ttm_global_release(struct ttm_global *glob)
> +{
> +	drm_global_item_unref(&glob->bo_ref);
> +	drm_global_item_unref(&glob->mem_ref);
> +}
> +
> +EXPORT_SYMBOL(ttm_global_release);
> diff --git a/include/drm/drm_global.h b/include/drm/drm_global.h
> index 3a830602a2e4..4482a9bbd6e9 100644
> --- a/include/drm/drm_global.h
> +++ b/include/drm/drm_global.h
> @@ -28,8 +28,16 @@
>   * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
>   */
>  
> +/*
> + *  The interfaces in this file are deprecated. Please use ttm_global
> + *  from <drm/ttm/ttm_global.h> instead.
> + */
> +
>  #ifndef _DRM_GLOBAL_H_
>  #define _DRM_GLOBAL_H_
> +
> +#include <linux/types.h>
> +
>  enum drm_global_types {
>  	DRM_GLOBAL_TTM_MEM = 0,
>  	DRM_GLOBAL_TTM_BO,
> diff --git a/include/drm/ttm/ttm_global.h b/include/drm/ttm/ttm_global.h
> new file mode 100644
> index 000000000000..06e791499f87
> --- /dev/null
> +++ b/include/drm/ttm/ttm_global.h
> @@ -0,0 +1,79 @@
> +/**************************************************************************
> + *
> + * Copyright 2008-2009 VMware, Inc., Palo Alto, CA., USA
> + * All Rights Reserved.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the
> + * "Software"), to deal in the Software without restriction, including
> + * without limitation the rights to use, copy, modify, merge, publish,
> + * distribute, sub license, and/or sell copies of the Software, and to
> + * permit persons to whom the Software is furnished to do so, subject to
> + * the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the
> + * next paragraph) shall be included in all copies or substantial portions
> + * of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
> + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
> + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
> + * USE OR OTHER DEALINGS IN THE SOFTWARE.
> + *
> + **************************************************************************/
> +
> +#ifndef _TTM_GLOBAL_H_
> +#define _TTM_GLOBAL_H_
> +
> +#include <drm/drm_global.h>
> +
> +struct ttm_bo_global;
> +
> +/**
> + * struct ttm_global - Stores references to global TTM state
> + */
> +struct ttm_global {
> +	struct drm_global_reference mem_ref;
> +	struct drm_global_reference bo_ref;
> +};
> +
> +/**
> + * ttm_global_init
> + *
> + * @glob: A pointer to a struct ttm_global that is about to be initialized
> + * @return Zero on success, or a negative error code otherwise.
> + *
> + * Initializes an instance of struct ttm_global with TTM's global state
> + */
> +int ttm_global_init(struct ttm_global *glob);
> +
> +/**
> + * ttm_global_release
> + *
> + * @glob: A pointer to an instance of struct ttm_global
> + *
> + * Releases an initialized instance of struct ttm_global. If the instance
> + * constains the final references to the global memory and BO, the global
> + * structures are released as well.
> + */
> +void ttm_global_release(struct ttm_global *glob);
> +
> +/**
> + * ttm_global_get_bo_global
> + *
> + * @glob A pointer to an instance of struct ttm_global
> + * @return A refernce to the global BO.
> + *
> + * Returns the global BO. The BO should be forwarded to the initialization
> + * of a driver's TTM BO device.
> + */
> +static inline struct ttm_bo_global*
> +ttm_global_get_bo_global(struct ttm_global *glob)
> +{
> +	return glob->bo_ref.object;
> +}
> +
> +#endif /* _TTM_GLOBAL_H_ */
> -- 
> 2.19.1
> 