Re: [PATCH v4 05/10] drm/ttm: Add vmap/vunmap to TTM and TTM GEM helpers

Re: [PATCH v4 05/10] drm/ttm: Add vmap/vunmap to TTM and TTM GEM helpers

[Thomas Zimmermann]

Hi

On Thu, 15 Oct 2020 18:49:09 +0200 Daniel Vetter <daniel@ffwll.ch> wrote:

> On Thu, Oct 15, 2020 at 04:08:13PM +0200, Christian König wrote:
> > Am 15.10.20 um 14:38 schrieb Thomas Zimmermann:
> > > The new functions ttm_bo_{vmap,vunmap}() map and unmap a TTM BO in
> > > kernel address space. The mapping's address is returned as struct
> > > dma_buf_map. Each function is a simplified version of TTM's existing
> > > kmap code. Both functions respect the memory's location ani/or
> > > writecombine flags.
> > > 
> > > On top TTM's functions, GEM TTM helpers got drm_gem_ttm_{vmap,vunmap}(),
> > > two helpers that convert a GEM object into the TTM BO and forward the
> > > call to TTM's vmap/vunmap. These helpers can be dropped into the rsp
> > > GEM object callbacks.
> > > 
> > > v4:
> > > 	* drop ttm_kmap_obj_to_dma_buf() in favor of vmap helpers
> > > (Daniel, Christian)
> > 
> > Bunch of minor comments below, but over all look very solid to me.
> 
> Yeah I think just duplicating the ttm bo map stuff for vmap is indeed the
> cleanest. And then we can maybe push the combinatorial monster into
> vmwgfx, which I think is the only user after this series. Or perhaps a
> dedicated set of helpers to map an invidual page (again using the
> dma_buf_map stuff).

From a quick look, I'd say it should be possible to have the same interface
for kmap/kunmap as for vmap/vunmap (i.e., parameters are bo and dma-buf-map).
All mapping state can be deduced from this. And struct ttm_bo_kmap_obj can be
killed off entirely.

Best regards
Thomas

> 
> I'll let Christian with the details, but at a high level this is
> definitely
> 
> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> Thanks a lot for doing all this.
> -Daniel
> 
> > 
> > > 
> > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> > > ---
> > >   drivers/gpu/drm/drm_gem_ttm_helper.c | 38 +++++++++++++++
> > >   drivers/gpu/drm/ttm/ttm_bo_util.c    | 72 ++++++++++++++++++++++++++++
> > >   include/drm/drm_gem_ttm_helper.h     |  6 +++
> > >   include/drm/ttm/ttm_bo_api.h         | 28 +++++++++++
> > >   include/linux/dma-buf-map.h          | 20 ++++++++
> > >   5 files changed, 164 insertions(+)
> > > 
> > > diff --git a/drivers/gpu/drm/drm_gem_ttm_helper.c
> > > b/drivers/gpu/drm/drm_gem_ttm_helper.c index 0e4fb9ba43ad..db4c14d78a30
> > > 100644 --- a/drivers/gpu/drm/drm_gem_ttm_helper.c
> > > +++ b/drivers/gpu/drm/drm_gem_ttm_helper.c
> > > @@ -49,6 +49,44 @@ void drm_gem_ttm_print_info(struct drm_printer *p,
> > > unsigned int indent, }
> > >   EXPORT_SYMBOL(drm_gem_ttm_print_info);
> > > +/**
> > > + * drm_gem_ttm_vmap() - vmap &ttm_buffer_object
> > > + * @gem: GEM object.
> > > + * @map: [out] returns the dma-buf mapping.
> > > + *
> > > + * Maps a GEM object with ttm_bo_vmap(). This function can be used as
> > > + * &drm_gem_object_funcs.vmap callback.
> > > + *
> > > + * Returns:
> > > + * 0 on success, or a negative errno code otherwise.
> > > + */
> > > +int drm_gem_ttm_vmap(struct drm_gem_object *gem,
> > > +		     struct dma_buf_map *map)
> > > +{
> > > +	struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(gem);
> > > +
> > > +	return ttm_bo_vmap(bo, map);
> > > +
> > > +}
> > > +EXPORT_SYMBOL(drm_gem_ttm_vmap);
> > > +
> > > +/**
> > > + * drm_gem_ttm_vunmap() - vunmap &ttm_buffer_object
> > > + * @gem: GEM object.
> > > + * @map: dma-buf mapping.
> > > + *
> > > + * Unmaps a GEM object with ttm_bo_vunmap(). This function can be used
> > > as
> > > + * &drm_gem_object_funcs.vmap callback.
> > > + */
> > > +void drm_gem_ttm_vunmap(struct drm_gem_object *gem,
> > > +			struct dma_buf_map *map)
> > > +{
> > > +	struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(gem);
> > > +
> > > +	ttm_bo_vunmap(bo, map);
> > > +}
> > > +EXPORT_SYMBOL(drm_gem_ttm_vunmap);
> > > +
> > >   /**
> > >    * drm_gem_ttm_mmap() - mmap &ttm_buffer_object
> > >    * @gem: GEM object.
> > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c
> > > b/drivers/gpu/drm/ttm/ttm_bo_util.c index bdee4df1f3f2..80c42c774c7d
> > > 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c
> > > +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
> > > @@ -32,6 +32,7 @@
> > >   #include <drm/ttm/ttm_bo_driver.h>
> > >   #include <drm/ttm/ttm_placement.h>
> > >   #include <drm/drm_vma_manager.h>
> > > +#include <linux/dma-buf-map.h>
> > >   #include <linux/io.h>
> > >   #include <linux/highmem.h>
> > >   #include <linux/wait.h>
> > > @@ -526,6 +527,77 @@ void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
> > >   }
> > >   EXPORT_SYMBOL(ttm_bo_kunmap);
> > > +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map)
> > > +{
> > > +	struct ttm_resource *mem = &bo->mem;
> > > +	int ret;
> > > +
> > > +	ret = ttm_mem_io_reserve(bo->bdev, mem);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	if (mem->bus.is_iomem) {
> > > +		void __iomem *vaddr_iomem;
> > > +		unsigned long size = bo->num_pages << PAGE_SHIFT;
> > 
> > Please use uint64_t here and make sure to cast bo->num_pages before
> > shifting.
> > 
> > We have an unit tests of allocating a 8GB BO and that should work on a
> > 32bit machine as well :)
> > 
> > > +
> > > +		if (mem->bus.addr)
> > > +			vaddr_iomem = (void *)(((u8 *)mem->bus.addr));
> > > +		else if (mem->placement & TTM_PL_FLAG_WC)
> > 
> > I've just nuked the TTM_PL_FLAG_WC flag in drm-misc-next. There is a new
> > mem->bus.caching enum as replacement.
> > 
> > > +			vaddr_iomem = ioremap_wc(mem->bus.offset,
> > > size);
> > > +		else
> > > +			vaddr_iomem = ioremap(mem->bus.offset, size);
> > > +
> > > +		if (!vaddr_iomem)
> > > +			return -ENOMEM;
> > > +
> > > +		dma_buf_map_set_vaddr_iomem(map, vaddr_iomem);
> > > +
> > > +	} else {
> > > +		struct ttm_operation_ctx ctx = {
> > > +			.interruptible = false,
> > > +			.no_wait_gpu = false
> > > +		};
> > > +		struct ttm_tt *ttm = bo->ttm;
> > > +		pgprot_t prot;
> > > +		void *vaddr;
> > > +
> > > +		BUG_ON(!ttm);
> > 
> > I think we can drop this, populate will just crash badly anyway.
> > 
> > > +
> > > +		ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
> > > +		if (ret)
> > > +			return ret;
> > > +
> > > +		/*
> > > +		 * We need to use vmap to get the desired page
> > > protection
> > > +		 * or to make the buffer object look contiguous.
> > > +		 */
> > > +		prot = ttm_io_prot(mem->placement, PAGE_KERNEL);
> > 
> > The calling convention has changed on drm-misc-next as well, but should be
> > trivial to adapt.
> > 
> > Regards,
> > Christian.
> > 
> > > +		vaddr = vmap(ttm->pages, bo->num_pages, 0, prot);
> > > +		if (!vaddr)
> > > +			return -ENOMEM;
> > > +
> > > +		dma_buf_map_set_vaddr(map, vaddr);
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +EXPORT_SYMBOL(ttm_bo_vmap);
> > > +
> > > +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map
> > > *map) +{
> > > +	if (dma_buf_map_is_null(map))
> > > +		return;
> > > +
> > > +	if (map->is_iomem)
> > > +		iounmap(map->vaddr_iomem);
> > > +	else
> > > +		vunmap(map->vaddr);
> > > +	dma_buf_map_clear(map);
> > > +
> > > +	ttm_mem_io_free(bo->bdev, &bo->mem);
> > > +}
> > > +EXPORT_SYMBOL(ttm_bo_vunmap);
> > > +
> > >   static int ttm_bo_wait_free_node(struct ttm_buffer_object *bo,
> > >   				 bool dst_use_tt)
> > >   {
> > > diff --git a/include/drm/drm_gem_ttm_helper.h
> > > b/include/drm/drm_gem_ttm_helper.h index 118cef76f84f..7c6d874910b8
> > > 100644 --- a/include/drm/drm_gem_ttm_helper.h
> > > +++ b/include/drm/drm_gem_ttm_helper.h
> > > @@ -10,11 +10,17 @@
> > >   #include <drm/ttm/ttm_bo_api.h>
> > >   #include <drm/ttm/ttm_bo_driver.h>
> > > +struct dma_buf_map;
> > > +
> > >   #define drm_gem_ttm_of_gem(gem_obj) \
> > >   	container_of(gem_obj, struct ttm_buffer_object, base)
> > >   void drm_gem_ttm_print_info(struct drm_printer *p, unsigned int
> > > indent, const struct drm_gem_object *gem);
> > > +int drm_gem_ttm_vmap(struct drm_gem_object *gem,
> > > +		     struct dma_buf_map *map);
> > > +void drm_gem_ttm_vunmap(struct drm_gem_object *gem,
> > > +			struct dma_buf_map *map);
> > >   int drm_gem_ttm_mmap(struct drm_gem_object *gem,
> > >   		     struct vm_area_struct *vma);
> > > diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
> > > index 37102e45e496..2c59a785374c 100644
> > > --- a/include/drm/ttm/ttm_bo_api.h
> > > +++ b/include/drm/ttm/ttm_bo_api.h
> > > @@ -48,6 +48,8 @@ struct ttm_bo_global;
> > >   struct ttm_bo_device;
> > > +struct dma_buf_map;
> > > +
> > >   struct drm_mm_node;
> > >   struct ttm_placement;
> > > @@ -494,6 +496,32 @@ int ttm_bo_kmap(struct ttm_buffer_object *bo,
> > > unsigned long start_page, */
> > >   void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
> > > +/**
> > > + * ttm_bo_vmap
> > > + *
> > > + * @bo: The buffer object.
> > > + * @map: pointer to a struct dma_buf_map representing the map.
> > > + *
> > > + * Sets up a kernel virtual mapping, using ioremap or vmap to the
> > > + * data in the buffer object. The parameter @map returns the virtual
> > > + * address as struct dma_buf_map. Unmap the buffer with
> > > ttm_bo_vunmap().
> > > + *
> > > + * Returns
> > > + * -ENOMEM: Out of memory.
> > > + * -EINVAL: Invalid range.
> > > + */
> > > +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
> > > +
> > > +/**
> > > + * ttm_bo_vunmap
> > > + *
> > > + * @bo: The buffer object.
> > > + * @map: Object describing the map to unmap.
> > > + *
> > > + * Unmaps a kernel map set up by ttm_bo_vmap().
> > > + */
> > > +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map
> > > *map); +
> > >   /**
> > >    * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
> > >    *
> > > diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h
> > > index fd1aba545fdf..2e8bbecb5091 100644
> > > --- a/include/linux/dma-buf-map.h
> > > +++ b/include/linux/dma-buf-map.h
> > > @@ -45,6 +45,12 @@
> > >    *
> > >    *	dma_buf_map_set_vaddr(&map. 0xdeadbeaf);
> > >    *
> > > + * To set an address in I/O memory, use dma_buf_map_set_vaddr_iomem().
> > > + *
> > > + * .. code-block:: c
> > > + *
> > > + *	dma_buf_map_set_vaddr_iomem(&map. 0xdeadbeaf);
> > > + *
> > >    * Test if a mapping is valid with either dma_buf_map_is_set() or
> > >    * dma_buf_map_is_null().
> > >    *
> > > @@ -118,6 +124,20 @@ static inline void dma_buf_map_set_vaddr(struct
> > > dma_buf_map *map, void *vaddr) map->is_iomem = false;
> > >   }
> > > +/**
> > > + * dma_buf_map_set_vaddr_iomem - Sets a dma-buf mapping structure to
> > > an address in I/O memory
> > > + * @map:		The dma-buf mapping structure
> > > + * @vaddr_iomem:	An I/O-memory address
> > > + *
> > > + * Sets the address and the I/O-memory flag.
> > > + */
> > > +static inline void dma_buf_map_set_vaddr_iomem(struct dma_buf_map *map,
> > > +					       void __iomem
> > > *vaddr_iomem) +{
> > > +	map->vaddr_iomem = vaddr_iomem;
> > > +	map->is_iomem = true;
> > > +}
> > > +
> > >   /**
> > >    * dma_buf_map_is_equal - Compares two dma-buf mapping structures for
> > > equality
> > >    * @lhs:	The dma-buf mapping structure
> > 
> 



-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer

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Re: [PATCH v4 05/10] drm/ttm: Add vmap/vunmap to TTM and TTM GEM helpers

[Christian König]

Am 15.10.20 um 19:52 schrieb Thomas Zimmermann:
> Hi
>
> On Thu, 15 Oct 2020 18:49:09 +0200 Daniel Vetter <daniel@ffwll.ch> wrote:
>
>> On Thu, Oct 15, 2020 at 04:08:13PM +0200, Christian König wrote:
>>> Am 15.10.20 um 14:38 schrieb Thomas Zimmermann:
>>>> The new functions ttm_bo_{vmap,vunmap}() map and unmap a TTM BO in
>>>> kernel address space. The mapping's address is returned as struct
>>>> dma_buf_map. Each function is a simplified version of TTM's existing
>>>> kmap code. Both functions respect the memory's location ani/or
>>>> writecombine flags.
>>>>
>>>> On top TTM's functions, GEM TTM helpers got drm_gem_ttm_{vmap,vunmap}(),
>>>> two helpers that convert a GEM object into the TTM BO and forward the
>>>> call to TTM's vmap/vunmap. These helpers can be dropped into the rsp
>>>> GEM object callbacks.
>>>>
>>>> v4:
>>>> 	* drop ttm_kmap_obj_to_dma_buf() in favor of vmap helpers
>>>> (Daniel, Christian)
>>> Bunch of minor comments below, but over all look very solid to me.
>> Yeah I think just duplicating the ttm bo map stuff for vmap is indeed the
>> cleanest. And then we can maybe push the combinatorial monster into
>> vmwgfx, which I think is the only user after this series. Or perhaps a
>> dedicated set of helpers to map an invidual page (again using the
>> dma_buf_map stuff).
>  From a quick look, I'd say it should be possible to have the same interface
> for kmap/kunmap as for vmap/vunmap (i.e., parameters are bo and dma-buf-map).
> All mapping state can be deduced from this. And struct ttm_bo_kmap_obj can be
> killed off entirely.

Yes, that would be rather nice to have.

Thanks,
Christian.

>
> Best regards
> Thomas
>
>> I'll let Christian with the details, but at a high level this is
>> definitely
>>
>> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>>
>> Thanks a lot for doing all this.
>> -Daniel
>>
>>>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>>>> ---
>>>>    drivers/gpu/drm/drm_gem_ttm_helper.c | 38 +++++++++++++++
>>>>    drivers/gpu/drm/ttm/ttm_bo_util.c    | 72 ++++++++++++++++++++++++++++
>>>>    include/drm/drm_gem_ttm_helper.h     |  6 +++
>>>>    include/drm/ttm/ttm_bo_api.h         | 28 +++++++++++
>>>>    include/linux/dma-buf-map.h          | 20 ++++++++
>>>>    5 files changed, 164 insertions(+)
>>>>
>>>> diff --git a/drivers/gpu/drm/drm_gem_ttm_helper.c
>>>> b/drivers/gpu/drm/drm_gem_ttm_helper.c index 0e4fb9ba43ad..db4c14d78a30
>>>> 100644 --- a/drivers/gpu/drm/drm_gem_ttm_helper.c
>>>> +++ b/drivers/gpu/drm/drm_gem_ttm_helper.c
>>>> @@ -49,6 +49,44 @@ void drm_gem_ttm_print_info(struct drm_printer *p,
>>>> unsigned int indent, }
>>>>    EXPORT_SYMBOL(drm_gem_ttm_print_info);
>>>> +/**
>>>> + * drm_gem_ttm_vmap() - vmap &ttm_buffer_object
>>>> + * @gem: GEM object.
>>>> + * @map: [out] returns the dma-buf mapping.
>>>> + *
>>>> + * Maps a GEM object with ttm_bo_vmap(). This function can be used as
>>>> + * &drm_gem_object_funcs.vmap callback.
>>>> + *
>>>> + * Returns:
>>>> + * 0 on success, or a negative errno code otherwise.
>>>> + */
>>>> +int drm_gem_ttm_vmap(struct drm_gem_object *gem,
>>>> +		     struct dma_buf_map *map)
>>>> +{
>>>> +	struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(gem);
>>>> +
>>>> +	return ttm_bo_vmap(bo, map);
>>>> +
>>>> +}
>>>> +EXPORT_SYMBOL(drm_gem_ttm_vmap);
>>>> +
>>>> +/**
>>>> + * drm_gem_ttm_vunmap() - vunmap &ttm_buffer_object
>>>> + * @gem: GEM object.
>>>> + * @map: dma-buf mapping.
>>>> + *
>>>> + * Unmaps a GEM object with ttm_bo_vunmap(). This function can be used
>>>> as
>>>> + * &drm_gem_object_funcs.vmap callback.
>>>> + */
>>>> +void drm_gem_ttm_vunmap(struct drm_gem_object *gem,
>>>> +			struct dma_buf_map *map)
>>>> +{
>>>> +	struct ttm_buffer_object *bo = drm_gem_ttm_of_gem(gem);
>>>> +
>>>> +	ttm_bo_vunmap(bo, map);
>>>> +}
>>>> +EXPORT_SYMBOL(drm_gem_ttm_vunmap);
>>>> +
>>>>    /**
>>>>     * drm_gem_ttm_mmap() - mmap &ttm_buffer_object
>>>>     * @gem: GEM object.
>>>> diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c
>>>> b/drivers/gpu/drm/ttm/ttm_bo_util.c index bdee4df1f3f2..80c42c774c7d
>>>> 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c
>>>> +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
>>>> @@ -32,6 +32,7 @@
>>>>    #include <drm/ttm/ttm_bo_driver.h>
>>>>    #include <drm/ttm/ttm_placement.h>
>>>>    #include <drm/drm_vma_manager.h>
>>>> +#include <linux/dma-buf-map.h>
>>>>    #include <linux/io.h>
>>>>    #include <linux/highmem.h>
>>>>    #include <linux/wait.h>
>>>> @@ -526,6 +527,77 @@ void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
>>>>    }
>>>>    EXPORT_SYMBOL(ttm_bo_kunmap);
>>>> +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map)
>>>> +{
>>>> +	struct ttm_resource *mem = &bo->mem;
>>>> +	int ret;
>>>> +
>>>> +	ret = ttm_mem_io_reserve(bo->bdev, mem);
>>>> +	if (ret)
>>>> +		return ret;
>>>> +
>>>> +	if (mem->bus.is_iomem) {
>>>> +		void __iomem *vaddr_iomem;
>>>> +		unsigned long size = bo->num_pages << PAGE_SHIFT;
>>> Please use uint64_t here and make sure to cast bo->num_pages before
>>> shifting.
>>>
>>> We have an unit tests of allocating a 8GB BO and that should work on a
>>> 32bit machine as well :)
>>>
>>>> +
>>>> +		if (mem->bus.addr)
>>>> +			vaddr_iomem = (void *)(((u8 *)mem->bus.addr));
>>>> +		else if (mem->placement & TTM_PL_FLAG_WC)
>>> I've just nuked the TTM_PL_FLAG_WC flag in drm-misc-next. There is a new
>>> mem->bus.caching enum as replacement.
>>>
>>>> +			vaddr_iomem = ioremap_wc(mem->bus.offset,
>>>> size);
>>>> +		else
>>>> +			vaddr_iomem = ioremap(mem->bus.offset, size);
>>>> +
>>>> +		if (!vaddr_iomem)
>>>> +			return -ENOMEM;
>>>> +
>>>> +		dma_buf_map_set_vaddr_iomem(map, vaddr_iomem);
>>>> +
>>>> +	} else {
>>>> +		struct ttm_operation_ctx ctx = {
>>>> +			.interruptible = false,
>>>> +			.no_wait_gpu = false
>>>> +		};
>>>> +		struct ttm_tt *ttm = bo->ttm;
>>>> +		pgprot_t prot;
>>>> +		void *vaddr;
>>>> +
>>>> +		BUG_ON(!ttm);
>>> I think we can drop this, populate will just crash badly anyway.
>>>
>>>> +
>>>> +		ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
>>>> +		if (ret)
>>>> +			return ret;
>>>> +
>>>> +		/*
>>>> +		 * We need to use vmap to get the desired page
>>>> protection
>>>> +		 * or to make the buffer object look contiguous.
>>>> +		 */
>>>> +		prot = ttm_io_prot(mem->placement, PAGE_KERNEL);
>>> The calling convention has changed on drm-misc-next as well, but should be
>>> trivial to adapt.
>>>
>>> Regards,
>>> Christian.
>>>
>>>> +		vaddr = vmap(ttm->pages, bo->num_pages, 0, prot);
>>>> +		if (!vaddr)
>>>> +			return -ENOMEM;
>>>> +
>>>> +		dma_buf_map_set_vaddr(map, vaddr);
>>>> +	}
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +EXPORT_SYMBOL(ttm_bo_vmap);
>>>> +
>>>> +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map
>>>> *map) +{
>>>> +	if (dma_buf_map_is_null(map))
>>>> +		return;
>>>> +
>>>> +	if (map->is_iomem)
>>>> +		iounmap(map->vaddr_iomem);
>>>> +	else
>>>> +		vunmap(map->vaddr);
>>>> +	dma_buf_map_clear(map);
>>>> +
>>>> +	ttm_mem_io_free(bo->bdev, &bo->mem);
>>>> +}
>>>> +EXPORT_SYMBOL(ttm_bo_vunmap);
>>>> +
>>>>    static int ttm_bo_wait_free_node(struct ttm_buffer_object *bo,
>>>>    				 bool dst_use_tt)
>>>>    {
>>>> diff --git a/include/drm/drm_gem_ttm_helper.h
>>>> b/include/drm/drm_gem_ttm_helper.h index 118cef76f84f..7c6d874910b8
>>>> 100644 --- a/include/drm/drm_gem_ttm_helper.h
>>>> +++ b/include/drm/drm_gem_ttm_helper.h
>>>> @@ -10,11 +10,17 @@
>>>>    #include <drm/ttm/ttm_bo_api.h>
>>>>    #include <drm/ttm/ttm_bo_driver.h>
>>>> +struct dma_buf_map;
>>>> +
>>>>    #define drm_gem_ttm_of_gem(gem_obj) \
>>>>    	container_of(gem_obj, struct ttm_buffer_object, base)
>>>>    void drm_gem_ttm_print_info(struct drm_printer *p, unsigned int
>>>> indent, const struct drm_gem_object *gem);
>>>> +int drm_gem_ttm_vmap(struct drm_gem_object *gem,
>>>> +		     struct dma_buf_map *map);
>>>> +void drm_gem_ttm_vunmap(struct drm_gem_object *gem,
>>>> +			struct dma_buf_map *map);
>>>>    int drm_gem_ttm_mmap(struct drm_gem_object *gem,
>>>>    		     struct vm_area_struct *vma);
>>>> diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
>>>> index 37102e45e496..2c59a785374c 100644
>>>> --- a/include/drm/ttm/ttm_bo_api.h
>>>> +++ b/include/drm/ttm/ttm_bo_api.h
>>>> @@ -48,6 +48,8 @@ struct ttm_bo_global;
>>>>    struct ttm_bo_device;
>>>> +struct dma_buf_map;
>>>> +
>>>>    struct drm_mm_node;
>>>>    struct ttm_placement;
>>>> @@ -494,6 +496,32 @@ int ttm_bo_kmap(struct ttm_buffer_object *bo,
>>>> unsigned long start_page, */
>>>>    void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map);
>>>> +/**
>>>> + * ttm_bo_vmap
>>>> + *
>>>> + * @bo: The buffer object.
>>>> + * @map: pointer to a struct dma_buf_map representing the map.
>>>> + *
>>>> + * Sets up a kernel virtual mapping, using ioremap or vmap to the
>>>> + * data in the buffer object. The parameter @map returns the virtual
>>>> + * address as struct dma_buf_map. Unmap the buffer with
>>>> ttm_bo_vunmap().
>>>> + *
>>>> + * Returns
>>>> + * -ENOMEM: Out of memory.
>>>> + * -EINVAL: Invalid range.
>>>> + */
>>>> +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map);
>>>> +
>>>> +/**
>>>> + * ttm_bo_vunmap
>>>> + *
>>>> + * @bo: The buffer object.
>>>> + * @map: Object describing the map to unmap.
>>>> + *
>>>> + * Unmaps a kernel map set up by ttm_bo_vmap().
>>>> + */
>>>> +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map
>>>> *map); +
>>>>    /**
>>>>     * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object.
>>>>     *
>>>> diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h
>>>> index fd1aba545fdf..2e8bbecb5091 100644
>>>> --- a/include/linux/dma-buf-map.h
>>>> +++ b/include/linux/dma-buf-map.h
>>>> @@ -45,6 +45,12 @@
>>>>     *
>>>>     *	dma_buf_map_set_vaddr(&map. 0xdeadbeaf);
>>>>     *
>>>> + * To set an address in I/O memory, use dma_buf_map_set_vaddr_iomem().
>>>> + *
>>>> + * .. code-block:: c
>>>> + *
>>>> + *	dma_buf_map_set_vaddr_iomem(&map. 0xdeadbeaf);
>>>> + *
>>>>     * Test if a mapping is valid with either dma_buf_map_is_set() or
>>>>     * dma_buf_map_is_null().
>>>>     *
>>>> @@ -118,6 +124,20 @@ static inline void dma_buf_map_set_vaddr(struct
>>>> dma_buf_map *map, void *vaddr) map->is_iomem = false;
>>>>    }
>>>> +/**
>>>> + * dma_buf_map_set_vaddr_iomem - Sets a dma-buf mapping structure to
>>>> an address in I/O memory
>>>> + * @map:		The dma-buf mapping structure
>>>> + * @vaddr_iomem:	An I/O-memory address
>>>> + *
>>>> + * Sets the address and the I/O-memory flag.
>>>> + */
>>>> +static inline void dma_buf_map_set_vaddr_iomem(struct dma_buf_map *map,
>>>> +					       void __iomem
>>>> *vaddr_iomem) +{
>>>> +	map->vaddr_iomem = vaddr_iomem;
>>>> +	map->is_iomem = true;
>>>> +}
>>>> +
>>>>    /**
>>>>     * dma_buf_map_is_equal - Compares two dma-buf mapping structures for
>>>> equality
>>>>     * @lhs:	The dma-buf mapping structure
>
>


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Re: [PATCH v4 09/10] dma-buf-map: Add memcpy and pointer-increment interfaces

[Thomas Zimmermann]

Hi Sam

On Fri, 16 Oct 2020 12:08:54 +0200 Sam Ravnborg <sam@ravnborg.org> wrote:

> Hi Thomas.
> 
> On Thu, Oct 15, 2020 at 02:38:05PM +0200, Thomas Zimmermann wrote:
> > To do framebuffer updates, one needs memcpy from system memory and a
> > pointer-increment function. Add both interfaces with documentation.
> > 
> > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> 
> Looks good.
> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>

Thanks. If you have the time, may I ask you to test this patchset on the
bochs/sparc64 system that failed with the original code?

Best regards
Thomas

> 
> > ---
> >  include/linux/dma-buf-map.h | 72 +++++++++++++++++++++++++++++++------
> >  1 file changed, 62 insertions(+), 10 deletions(-)
> > 
> > diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h
> > index 2e8bbecb5091..6ca0f304dda2 100644
> > --- a/include/linux/dma-buf-map.h
> > +++ b/include/linux/dma-buf-map.h
> > @@ -32,6 +32,14 @@
> >   * accessing the buffer. Use the returned instance and the helper
> > functions
> >   * to access the buffer's memory in the correct way.
> >   *
> > + * The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers
> > are
> > + * actually independent from the dma-buf infrastructure. When sharing
> > buffers
> > + * among devices, drivers have to know the location of the memory to
> > access
> > + * the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>`
> > + * solves this problem for dma-buf and its users. If other drivers or
> > + * sub-systems require similar functionality, the type could be
> > generalized
> > + * and moved to a more prominent header file.
> > + *
> >   * Open-coding access to :c:type:`struct dma_buf_map <dma_buf_map>` is
> >   * considered bad style. Rather then accessing its fields directly, use
> > one
> >   * of the provided helper functions, or implement your own. For example,
> > @@ -51,6 +59,14 @@
> >   *
> >   *	dma_buf_map_set_vaddr_iomem(&map. 0xdeadbeaf);
> >   *
> > + * Instances of struct dma_buf_map do not have to be cleaned up, but
> > + * can be cleared to NULL with dma_buf_map_clear(). Cleared mappings
> > + * always refer to system memory.
> > + *
> > + * .. code-block:: c
> > + *
> > + *	dma_buf_map_clear(&map);
> > + *
> >   * Test if a mapping is valid with either dma_buf_map_is_set() or
> >   * dma_buf_map_is_null().
> >   *
> > @@ -73,17 +89,19 @@
> >   *	if (dma_buf_map_is_equal(&sys_map, &io_map))
> >   *		// always false
> >   *
> > - * Instances of struct dma_buf_map do not have to be cleaned up, but
> > - * can be cleared to NULL with dma_buf_map_clear(). Cleared mappings
> > - * always refer to system memory.
> > + * A set up instance of struct dma_buf_map can be used to access or
> > manipulate
> > + * the buffer memory. Depending on the location of the memory, the
> > provided
> > + * helpers will pick the correct operations. Data can be copied into the
> > memory
> > + * with dma_buf_map_memcpy_to(). The address can be manipulated with
> > + * dma_buf_map_incr().
> >   *
> > - * The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers
> > are
> > - * actually independent from the dma-buf infrastructure. When sharing
> > buffers
> > - * among devices, drivers have to know the location of the memory to
> > access
> > - * the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>`
> > - * solves this problem for dma-buf and its users. If other drivers or
> > - * sub-systems require similar functionality, the type could be
> > generalized
> > - * and moved to a more prominent header file.
> > + * .. code-block:: c
> > + *
> > + *	const void *src = ...; // source buffer
> > + *	size_t len = ...; // length of src
> > + *
> > + *	dma_buf_map_memcpy_to(&map, src, len);
> > + *	dma_buf_map_incr(&map, len); // go to first byte after the
> > memcpy */
> >  
> >  /**
> > @@ -210,4 +228,38 @@ static inline void dma_buf_map_clear(struct
> > dma_buf_map *map) }
> >  }
> >  
> > +/**
> > + * dma_buf_map_memcpy_to - Memcpy into dma-buf mapping
> > + * @dst:	The dma-buf mapping structure
> > + * @src:	The source buffer
> > + * @len:	The number of byte in src
> > + *
> > + * Copies data into a dma-buf mapping. The source buffer is in system
> > + * memory. Depending on the buffer's location, the helper picks the
> > correct
> > + * method of accessing the memory.
> > + */
> > +static inline void dma_buf_map_memcpy_to(struct dma_buf_map *dst, const
> > void *src, size_t len) +{
> > +	if (dst->is_iomem)
> > +		memcpy_toio(dst->vaddr_iomem, src, len);
> > +	else
> > +		memcpy(dst->vaddr, src, len);
> > +}
> > +
> > +/**
> > + * dma_buf_map_incr - Increments the address stored in a dma-buf mapping
> > + * @map:	The dma-buf mapping structure
> > + * @incr:	The number of bytes to increment
> > + *
> > + * Increments the address stored in a dma-buf mapping. Depending on the
> > + * buffer's location, the correct value will be updated.
> > + */
> > +static inline void dma_buf_map_incr(struct dma_buf_map *map, size_t incr)
> > +{
> > +	if (map->is_iomem)
> > +		map->vaddr_iomem += incr;
> > +	else
> > +		map->vaddr += incr;
> > +}
> > +
> >  #endif /* __DMA_BUF_MAP_H__ */
> > -- 
> > 2.28.0
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel



-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer

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Re: [PATCH v4 10/10] drm/fb_helper: Support framebuffers in I/O memory

[Thomas Zimmermann]

Hi

On Fri, 16 Oct 2020 12:58:54 +0200 Sam Ravnborg <sam@ravnborg.org> wrote:

> Hi Thomas.
> 
> On Thu, Oct 15, 2020 at 02:38:06PM +0200, Thomas Zimmermann wrote:
> > At least sparc64 requires I/O-specific access to framebuffers. This
> > patch updates the fbdev console accordingly.
> > 
> > For drivers with direct access to the framebuffer memory, the callback
> > functions in struct fb_ops test for the type of memory and call the rsp
> > fb_sys_ of fb_cfb_ functions.
> > 
> > For drivers that employ a shadow buffer, fbdev's blit function retrieves
> > the framebuffer address as struct dma_buf_map, and uses dma_buf_map
> > interfaces to access the buffer.
> > 
> > The bochs driver on sparc64 uses a workaround to flag the framebuffer as
> > I/O memory and avoid a HW exception. With the introduction of struct
> > dma_buf_map, this is not required any longer. The patch removes the rsp
> > code from both, bochs and fbdev.
> > 
> > v4:
> > 	* move dma_buf_map changes into separate patch (Daniel)
> > 	* TODO list: comment on fbdev updates (Daniel)
> 
> I have been offline for a while so have not followed all the threads on
> this. So may comments below may well be addressed but I failed to see
> it.
> 
> If the point about fb_sync is already addressed/considered then:
> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>

It has not been brought up yet. See below.

> 
> 
> > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> > ---
> >  Documentation/gpu/todo.rst        |  19 ++-
> >  drivers/gpu/drm/bochs/bochs_kms.c |   1 -
> >  drivers/gpu/drm/drm_fb_helper.c   | 217 ++++++++++++++++++++++++++++--
> >  include/drm/drm_mode_config.h     |  12 --
> >  4 files changed, 220 insertions(+), 29 deletions(-)
> > 
> > diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
> > index 7e6fc3c04add..638b7f704339 100644
> > --- a/Documentation/gpu/todo.rst
> > +++ b/Documentation/gpu/todo.rst
> > @@ -197,13 +197,28 @@ Convert drivers to use drm_fbdev_generic_setup()
> >  ------------------------------------------------
> >  
> >  Most drivers can use drm_fbdev_generic_setup(). Driver have to implement
> > -atomic modesetting and GEM vmap support. Current generic fbdev emulation
> > -expects the framebuffer in system memory (or system-like memory).
> > +atomic modesetting and GEM vmap support. Historically, generic fbdev
> > emulation +expected the framebuffer in system memory or system-like
> > memory. By employing +struct dma_buf_map, drivers with frambuffers in I/O
> > memory can be supported +as well.
> >  
> >  Contact: Maintainer of the driver you plan to convert
> >  
> >  Level: Intermediate
> >  
> > +Reimplement functions in drm_fbdev_fb_ops without fbdev
> > +-------------------------------------------------------
> > +
> > +A number of callback functions in drm_fbdev_fb_ops could benefit from
> > +being rewritten without dependencies on the fbdev module. Some of the
> > +helpers could further benefit from using struct dma_buf_map instead of
> > +raw pointers.
> > +
> > +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter
> > +
> > +Level: Advanced
> > +
> > +
> >  drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup
> >  -----------------------------------------------------------------
> >  
> > diff --git a/drivers/gpu/drm/bochs/bochs_kms.c
> > b/drivers/gpu/drm/bochs/bochs_kms.c index 13d0d04c4457..853081d186d5
> > 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c
> > +++ b/drivers/gpu/drm/bochs/bochs_kms.c
> > @@ -151,7 +151,6 @@ int bochs_kms_init(struct bochs_device *bochs)
> >  	bochs->dev->mode_config.preferred_depth = 24;
> >  	bochs->dev->mode_config.prefer_shadow = 0;
> >  	bochs->dev->mode_config.prefer_shadow_fbdev = 1;
> > -	bochs->dev->mode_config.fbdev_use_iomem = true;
> >  	bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order =
> > true; 
> >  	bochs->dev->mode_config.funcs = &bochs_mode_funcs;
> Good to see this workaround gone again!
> 
> > diff --git a/drivers/gpu/drm/drm_fb_helper.c
> > b/drivers/gpu/drm/drm_fb_helper.c index 6212cd7cde1d..462b0c130ebb 100644
> > --- a/drivers/gpu/drm/drm_fb_helper.c
> > +++ b/drivers/gpu/drm/drm_fb_helper.c
> > @@ -372,24 +372,22 @@ static void drm_fb_helper_resume_worker(struct
> > work_struct *work) }
> >  
> >  static void drm_fb_helper_dirty_blit_real(struct drm_fb_helper
> > *fb_helper,
> > -					  struct drm_clip_rect *clip)
> > +					  struct drm_clip_rect *clip,
> > +					  struct dma_buf_map *dst)
> >  {
> >  	struct drm_framebuffer *fb = fb_helper->fb;
> >  	unsigned int cpp = fb->format->cpp[0];
> >  	size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp;
> >  	void *src = fb_helper->fbdev->screen_buffer + offset;
> > -	void *dst = fb_helper->buffer->map.vaddr + offset;
> >  	size_t len = (clip->x2 - clip->x1) * cpp;
> >  	unsigned int y;
> >  
> > -	for (y = clip->y1; y < clip->y2; y++) {
> > -		if (!fb_helper->dev->mode_config.fbdev_use_iomem)
> > -			memcpy(dst, src, len);
> > -		else
> > -			memcpy_toio((void __iomem *)dst, src, len);
> > +	dma_buf_map_incr(dst, offset); /* go to first pixel within clip
> > rect */ 
> > +	for (y = clip->y1; y < clip->y2; y++) {
> > +		dma_buf_map_memcpy_to(dst, src, len);
> > +		dma_buf_map_incr(dst, fb->pitches[0]);
> >  		src += fb->pitches[0];
> > -		dst += fb->pitches[0];
> >  	}
> >  }
> >  
> > @@ -417,8 +415,9 @@ static void drm_fb_helper_dirty_work(struct
> > work_struct *work) ret = drm_client_buffer_vmap(helper->buffer, &map);
> >  			if (ret)
> >  				return;
> > -			drm_fb_helper_dirty_blit_real(helper,
> > &clip_copy);
> > +			drm_fb_helper_dirty_blit_real(helper,
> > &clip_copy, &map); }
> > +
> >  		if (helper->fb->funcs->dirty)
> >  			helper->fb->funcs->dirty(helper->fb, NULL, 0, 0,
> >  						 &clip_copy, 1);
> > @@ -755,6 +754,136 @@ void drm_fb_helper_sys_imageblit(struct fb_info
> > *info, }
> >  EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
> >  
> So far everything looks good.
> 
> > +static ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user
> > *buf,
> > +				      size_t count, loff_t *ppos)
> > +{
> > +	unsigned long p = *ppos;
> > +	u8 *dst;
> > +	u8 __iomem *src;
> > +	int c, err = 0;
> > +	unsigned long total_size;
> > +	unsigned long alloc_size;
> > +	ssize_t ret = 0;
> > +
> > +	if (info->state != FBINFO_STATE_RUNNING)
> > +		return -EPERM;
> > +
> > +	total_size = info->screen_size;
> > +
> > +	if (total_size == 0)
> > +		total_size = info->fix.smem_len;
> > +
> > +	if (p >= total_size)
> > +		return 0;
> > +
> > +	if (count >= total_size)
> > +		count = total_size;
> > +
> > +	if (count + p > total_size)
> > +		count = total_size - p;
> > +
> > +	src = (u8 __iomem *)(info->screen_base + p);
> screen_base is a char __iomem * - so this cast looks semi redundant.

I took the basic code from fbdev. Maybe there's a reason for the case,
otherwise I'll remove it.

> 
> > +
> > +	alloc_size = min(count, PAGE_SIZE);
> > +
> > +	dst = kmalloc(alloc_size, GFP_KERNEL);
> > +	if (!dst)
> > +		return -ENOMEM;
> > +
> Same comment as below about fb_sync.
> 
> 
> > +	while (count) {
> > +		c = min(count, alloc_size);
> > +
> > +		memcpy_fromio(dst, src, c);
> > +		if (copy_to_user(buf, dst, c)) {
> > +			err = -EFAULT;
> > +			break;
> > +		}
> > +
> > +		src += c;
> > +		*ppos += c;
> > +		buf += c;
> > +		ret += c;
> > +		count -= c;
> > +	}
> > +
> > +	kfree(dst);
> > +
> > +	if (err)
> > +		return err;
> > +
> > +	return ret;
> > +}
> > +
> > +static ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char
> > __user *buf,
> > +				       size_t count, loff_t *ppos)
> > +{
> > +	unsigned long p = *ppos;
> > +	u8 *src;
> > +	u8 __iomem *dst;
> > +	int c, err = 0;
> > +	unsigned long total_size;
> > +	unsigned long alloc_size;
> > +	ssize_t ret = 0;
> > +
> > +	if (info->state != FBINFO_STATE_RUNNING)
> > +		return -EPERM;
> > +
> > +	total_size = info->screen_size;
> > +
> > +	if (total_size == 0)
> > +		total_size = info->fix.smem_len;
> > +
> > +	if (p > total_size)
> > +		return -EFBIG;
> > +
> > +	if (count > total_size) {
> > +		err = -EFBIG;
> > +		count = total_size;
> > +	}
> > +
> > +	if (count + p > total_size) {
> > +		/*
> > +		 * The framebuffer is too small. We do the
> > +		 * copy operation, but return an error code
> > +		 * afterwards. Taken from fbdev.
> > +		 */
> > +		if (!err)
> > +			err = -ENOSPC;
> > +		count = total_size - p;
> > +	}
> > +
> > +	alloc_size = min(count, PAGE_SIZE);
> > +
> > +	src = kmalloc(alloc_size, GFP_KERNEL);
> > +	if (!src)
> > +		return -ENOMEM;
> > +
> > +	dst = (u8 __iomem *)(info->screen_base + p);
> > +
> 
> The fbdev variant call the fb_sync callback here.
> noveau and gma500 implments the fb_sync callback - but no-one else.

These drivers implement some form of HW acceleration. If they have a HW
blit/draw/etc op queued up, they have to wait for it to complete. Otherwise,
the copied memory would contain an old state. The fb_sync acts as the fence.

Fbdev only uses software copying, so the fb_sync is not required.

From what I heard, the HW acceleration is not useful on modern machines. I
hope to convert more drivers to generic fbdev after these patches for
I/O-memory support have been merged.

> 
> 
> > +	while (count) {
> > +		c = min(count, alloc_size);
> > +
> > +		if (copy_from_user(src, buf, c)) {
> > +			err = -EFAULT;
> > +			break;
> > +		}
> > +		memcpy_toio(dst, src, c);
> When we rewrite this part to use dma_buf_map_memcpy_to() then we can
> merge the two variants of helper_{sys,cfb}_read()?
> Which is part of the todo - so OK

I'm not sure if dma_buf_map is a good fit here. The I/O-memory function does
an additional copy between system memory and I/O memory. Of course, the top
and bottom of both functions are similar and could probably be shared.

Best regards
Thomas

> > +
> > +		dst += c;
> > +		*ppos += c;
> > +		buf += c;
> > +		ret += c;
> > +		count -= c;
> > +	}
> > +
> > +	kfree(src);
> > +
> > +	if (err)
> > +		return err;
> > +
> > +	return ret;
> > +}
> > +
> >  /**
> >   * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
> >   * @info: fbdev registered by the helper
> > @@ -2027,6 +2156,66 @@ static int drm_fbdev_fb_mmap(struct fb_info *info,
> > struct vm_area_struct *vma) return -ENODEV;
> >  }
> >  
> > +static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf,
> > +				 size_t count, loff_t *ppos)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct drm_client_buffer *buffer = fb_helper->buffer;
> > +
> > +	if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem)
> > +		return drm_fb_helper_sys_read(info, buf, count, ppos);
> > +	else
> > +		return drm_fb_helper_cfb_read(info, buf, count, ppos);
> > +}
> > +
> > +static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char
> > __user *buf,
> > +				  size_t count, loff_t *ppos)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct drm_client_buffer *buffer = fb_helper->buffer;
> > +
> > +	if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem)
> > +		return drm_fb_helper_sys_write(info, buf, count, ppos);
> > +	else
> > +		return drm_fb_helper_cfb_write(info, buf, count, ppos);
> > +}
> > +
> > +static void drm_fbdev_fb_fillrect(struct fb_info *info,
> > +				  const struct fb_fillrect *rect)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct drm_client_buffer *buffer = fb_helper->buffer;
> > +
> > +	if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem)
> > +		drm_fb_helper_sys_fillrect(info, rect);
> > +	else
> > +		drm_fb_helper_cfb_fillrect(info, rect);
> > +}
> > +
> > +static void drm_fbdev_fb_copyarea(struct fb_info *info,
> > +				  const struct fb_copyarea *area)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct drm_client_buffer *buffer = fb_helper->buffer;
> > +
> > +	if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem)
> > +		drm_fb_helper_sys_copyarea(info, area);
> > +	else
> > +		drm_fb_helper_cfb_copyarea(info, area);
> > +}
> > +
> > +static void drm_fbdev_fb_imageblit(struct fb_info *info,
> > +				   const struct fb_image *image)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct drm_client_buffer *buffer = fb_helper->buffer;
> > +
> > +	if (drm_fbdev_use_shadow_fb(fb_helper) || !buffer->map.is_iomem)
> > +		drm_fb_helper_sys_imageblit(info, image);
> > +	else
> > +		drm_fb_helper_cfb_imageblit(info, image);
> > +}
> > +
> >  static const struct fb_ops drm_fbdev_fb_ops = {
> >  	.owner		= THIS_MODULE,
> >  	DRM_FB_HELPER_DEFAULT_OPS,
> > @@ -2034,11 +2223,11 @@ static const struct fb_ops drm_fbdev_fb_ops = {
> >  	.fb_release	= drm_fbdev_fb_release,
> >  	.fb_destroy	= drm_fbdev_fb_destroy,
> >  	.fb_mmap	= drm_fbdev_fb_mmap,
> > -	.fb_read	= drm_fb_helper_sys_read,
> > -	.fb_write	= drm_fb_helper_sys_write,
> > -	.fb_fillrect	= drm_fb_helper_sys_fillrect,
> > -	.fb_copyarea	= drm_fb_helper_sys_copyarea,
> > -	.fb_imageblit	= drm_fb_helper_sys_imageblit,
> > +	.fb_read	= drm_fbdev_fb_read,
> > +	.fb_write	= drm_fbdev_fb_write,
> > +	.fb_fillrect	= drm_fbdev_fb_fillrect,
> > +	.fb_copyarea	= drm_fbdev_fb_copyarea,
> > +	.fb_imageblit	= drm_fbdev_fb_imageblit,
> >  };
> >  
> >  static struct fb_deferred_io drm_fbdev_defio = {
> > diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
> > index 5ffbb4ed5b35..ab424ddd7665 100644
> > --- a/include/drm/drm_mode_config.h
> > +++ b/include/drm/drm_mode_config.h
> > @@ -877,18 +877,6 @@ struct drm_mode_config {
> >  	 */
> >  	bool prefer_shadow_fbdev;
> >  
> > -	/**
> > -	 * @fbdev_use_iomem:
> > -	 *
> > -	 * Set to true if framebuffer reside in iomem.
> > -	 * When set to true memcpy_toio() is used when copying the
> > framebuffer in
> > -	 * drm_fb_helper.drm_fb_helper_dirty_blit_real().
> > -	 *
> > -	 * FIXME: This should be replaced with a per-mapping is_iomem
> > -	 * flag (like ttm does), and then used everywhere in fbdev code.
> > -	 */
> > -	bool fbdev_use_iomem;
> > -
> >  	/**
> >  	 * @quirk_addfb_prefer_xbgr_30bpp:
> >  	 *
> > -- 
> > 2.28.0
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel



-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer

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