diff mbox

[9/9] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames()

Message ID 1431522495-4692-10-git-send-email-jack@suse.cz (mailing list archive)
State New, archived
Headers show

Commit Message

Jan Kara May 13, 2015, 1:08 p.m. UTC
Convert g2d_userptr_get_dma_addr() to pin pages using get_vaddr_frames().
This removes the knowledge about vmas and mmap_sem locking from exynos
driver. Also it fixes a problem that the function has been mapping user
provided address without holding mmap_sem.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/gpu/drm/exynos/exynos_drm_g2d.c | 89 ++++++++++--------------------
 drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 ---------------------------------
 2 files changed, 29 insertions(+), 157 deletions(-)

Comments

Inki Dae May 14, 2015, 10:51 a.m. UTC | #1
Hi,

On 2015? 05? 13? 22:08, Jan Kara wrote:
> Convert g2d_userptr_get_dma_addr() to pin pages using get_vaddr_frames().
> This removes the knowledge about vmas and mmap_sem locking from exynos
> driver. Also it fixes a problem that the function has been mapping user
> provided address without holding mmap_sem.
> 
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---
>  drivers/gpu/drm/exynos/exynos_drm_g2d.c | 89 ++++++++++--------------------
>  drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 ---------------------------------
>  2 files changed, 29 insertions(+), 157 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> index 81a250830808..265519c0fe2d 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> @@ -190,10 +190,8 @@ struct g2d_cmdlist_userptr {
>  	dma_addr_t		dma_addr;
>  	unsigned long		userptr;
>  	unsigned long		size;
> -	struct page		**pages;
> -	unsigned int		npages;
> +	struct frame_vector	*vec;
>  	struct sg_table		*sgt;
> -	struct vm_area_struct	*vma;
>  	atomic_t		refcount;
>  	bool			in_pool;
>  	bool			out_of_list;
> @@ -363,6 +361,7 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev,
>  {
>  	struct g2d_cmdlist_userptr *g2d_userptr =
>  					(struct g2d_cmdlist_userptr *)obj;
> +	struct page **pages;
>  
>  	if (!obj)
>  		return;
> @@ -382,19 +381,21 @@ out:
>  	exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt,
>  					DMA_BIDIRECTIONAL);
>  
> -	exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
> -					g2d_userptr->npages,
> -					g2d_userptr->vma);
> +	pages = frame_vector_pages(g2d_userptr->vec);
> +	if (!IS_ERR(pages)) {
> +		int i;
>  
> -	exynos_gem_put_vma(g2d_userptr->vma);
> +		for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++)
> +			set_page_dirty_lock(pages[i]);
> +	}
> +	put_vaddr_frames(g2d_userptr->vec);
> +	frame_vector_destroy(g2d_userptr->vec);
>  
>  	if (!g2d_userptr->out_of_list)
>  		list_del_init(&g2d_userptr->list);
>  
>  	sg_free_table(g2d_userptr->sgt);
>  	kfree(g2d_userptr->sgt);
> -
> -	drm_free_large(g2d_userptr->pages);
>  	kfree(g2d_userptr);
>  }
>  
> @@ -413,6 +414,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
>  	struct vm_area_struct *vma;
>  	unsigned long start, end;
>  	unsigned int npages, offset;
> +	struct frame_vector *vec;
>  	int ret;
>  
>  	if (!size) {
> @@ -456,65 +458,37 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
>  		return ERR_PTR(-ENOMEM);
>  
>  	atomic_set(&g2d_userptr->refcount, 1);
> +	g2d_userptr->size = size;
>  
>  	start = userptr & PAGE_MASK;
>  	offset = userptr & ~PAGE_MASK;
>  	end = PAGE_ALIGN(userptr + size);
>  	npages = (end - start) >> PAGE_SHIFT;
> -	g2d_userptr->npages = npages;
> -
> -	pages = drm_calloc_large(npages, sizeof(struct page *));

The declaration to pages isn't needed anymore because you removed it.

> -	if (!pages) {
> -		DRM_ERROR("failed to allocate pages.\n");
> -		ret = -ENOMEM;
> +	vec = g2d_userptr->vec = frame_vector_create(npages);

I think you can use g2d_userptr->vec so it seems that vec isn't needed.

> +	if (!vec)
>  		goto err_free;
> -	}
>  
> -	down_read(&current->mm->mmap_sem);
> -	vma = find_vma(current->mm, userptr);

For vma, ditto.

Thanks,
Inki Dae

[--SNIP--]
Hans Verkuil June 10, 2015, 9:07 a.m. UTC | #2
For unclear reasons my SoB was missing in my pull request. So add it now:

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Regards,

	Hans

On 05/13/15 15:08, Jan Kara wrote:
> Convert g2d_userptr_get_dma_addr() to pin pages using get_vaddr_frames().
> This removes the knowledge about vmas and mmap_sem locking from exynos
> driver. Also it fixes a problem that the function has been mapping user
> provided address without holding mmap_sem.
> 
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---
>  drivers/gpu/drm/exynos/exynos_drm_g2d.c | 89 ++++++++++--------------------
>  drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 ---------------------------------
>  2 files changed, 29 insertions(+), 157 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> index 81a250830808..265519c0fe2d 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
> @@ -190,10 +190,8 @@ struct g2d_cmdlist_userptr {
>  	dma_addr_t		dma_addr;
>  	unsigned long		userptr;
>  	unsigned long		size;
> -	struct page		**pages;
> -	unsigned int		npages;
> +	struct frame_vector	*vec;
>  	struct sg_table		*sgt;
> -	struct vm_area_struct	*vma;
>  	atomic_t		refcount;
>  	bool			in_pool;
>  	bool			out_of_list;
> @@ -363,6 +361,7 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev,
>  {
>  	struct g2d_cmdlist_userptr *g2d_userptr =
>  					(struct g2d_cmdlist_userptr *)obj;
> +	struct page **pages;
>  
>  	if (!obj)
>  		return;
> @@ -382,19 +381,21 @@ out:
>  	exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt,
>  					DMA_BIDIRECTIONAL);
>  
> -	exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
> -					g2d_userptr->npages,
> -					g2d_userptr->vma);
> +	pages = frame_vector_pages(g2d_userptr->vec);
> +	if (!IS_ERR(pages)) {
> +		int i;
>  
> -	exynos_gem_put_vma(g2d_userptr->vma);
> +		for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++)
> +			set_page_dirty_lock(pages[i]);
> +	}
> +	put_vaddr_frames(g2d_userptr->vec);
> +	frame_vector_destroy(g2d_userptr->vec);
>  
>  	if (!g2d_userptr->out_of_list)
>  		list_del_init(&g2d_userptr->list);
>  
>  	sg_free_table(g2d_userptr->sgt);
>  	kfree(g2d_userptr->sgt);
> -
> -	drm_free_large(g2d_userptr->pages);
>  	kfree(g2d_userptr);
>  }
>  
> @@ -413,6 +414,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
>  	struct vm_area_struct *vma;
>  	unsigned long start, end;
>  	unsigned int npages, offset;
> +	struct frame_vector *vec;
>  	int ret;
>  
>  	if (!size) {
> @@ -456,65 +458,37 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
>  		return ERR_PTR(-ENOMEM);
>  
>  	atomic_set(&g2d_userptr->refcount, 1);
> +	g2d_userptr->size = size;
>  
>  	start = userptr & PAGE_MASK;
>  	offset = userptr & ~PAGE_MASK;
>  	end = PAGE_ALIGN(userptr + size);
>  	npages = (end - start) >> PAGE_SHIFT;
> -	g2d_userptr->npages = npages;
> -
> -	pages = drm_calloc_large(npages, sizeof(struct page *));
> -	if (!pages) {
> -		DRM_ERROR("failed to allocate pages.\n");
> -		ret = -ENOMEM;
> +	vec = g2d_userptr->vec = frame_vector_create(npages);
> +	if (!vec)
>  		goto err_free;
> -	}
>  
> -	down_read(&current->mm->mmap_sem);
> -	vma = find_vma(current->mm, userptr);
> -	if (!vma) {
> -		up_read(&current->mm->mmap_sem);
> -		DRM_ERROR("failed to get vm region.\n");
> +	ret = get_vaddr_frames(start, npages, 1, 1, vec);
> +	if (ret != npages) {
> +		DRM_ERROR("failed to get user pages from userptr.\n");
> +		if (ret < 0)
> +			goto err_destroy_framevec;
>  		ret = -EFAULT;
> -		goto err_free_pages;
> +		goto err_put_framevec;
>  	}
> -
> -	if (vma->vm_end < userptr + size) {
> -		up_read(&current->mm->mmap_sem);
> -		DRM_ERROR("vma is too small.\n");
> +	if (frame_vector_to_pages(vec) < 0) {
>  		ret = -EFAULT;
> -		goto err_free_pages;
> +		goto err_put_framevec;
>  	}
>  
> -	g2d_userptr->vma = exynos_gem_get_vma(vma);
> -	if (!g2d_userptr->vma) {
> -		up_read(&current->mm->mmap_sem);
> -		DRM_ERROR("failed to copy vma.\n");
> -		ret = -ENOMEM;
> -		goto err_free_pages;
> -	}
> -
> -	g2d_userptr->size = size;
> -
> -	ret = exynos_gem_get_pages_from_userptr(start & PAGE_MASK,
> -						npages, pages, vma);
> -	if (ret < 0) {
> -		up_read(&current->mm->mmap_sem);
> -		DRM_ERROR("failed to get user pages from userptr.\n");
> -		goto err_put_vma;
> -	}
> -
> -	up_read(&current->mm->mmap_sem);
> -	g2d_userptr->pages = pages;
> -
>  	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
>  	if (!sgt) {
>  		ret = -ENOMEM;
> -		goto err_free_userptr;
> +		goto err_put_framevec;
>  	}
>  
> -	ret = sg_alloc_table_from_pages(sgt, pages, npages, offset,
> -					size, GFP_KERNEL);
> +	ret = sg_alloc_table_from_pages(sgt, frame_vector_pages(vec), npages,
> +					offset, size, GFP_KERNEL);
>  	if (ret < 0) {
>  		DRM_ERROR("failed to get sgt from pages.\n");
>  		goto err_free_sgt;
> @@ -549,16 +523,11 @@ err_sg_free_table:
>  err_free_sgt:
>  	kfree(sgt);
>  
> -err_free_userptr:
> -	exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
> -					g2d_userptr->npages,
> -					g2d_userptr->vma);
> -
> -err_put_vma:
> -	exynos_gem_put_vma(g2d_userptr->vma);
> +err_put_framevec:
> +	put_vaddr_frames(vec);
>  
> -err_free_pages:
> -	drm_free_large(pages);
> +err_destroy_framevec:
> +	frame_vector_destroy(vec);
>  
>  err_free:
>  	kfree(g2d_userptr);
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
> index 0d5b9698d384..47068ae44ced 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
> @@ -378,103 +378,6 @@ int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
>  	return 0;
>  }
>  
> -struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma)
> -{
> -	struct vm_area_struct *vma_copy;
> -
> -	vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
> -	if (!vma_copy)
> -		return NULL;
> -
> -	if (vma->vm_ops && vma->vm_ops->open)
> -		vma->vm_ops->open(vma);
> -
> -	if (vma->vm_file)
> -		get_file(vma->vm_file);
> -
> -	memcpy(vma_copy, vma, sizeof(*vma));
> -
> -	vma_copy->vm_mm = NULL;
> -	vma_copy->vm_next = NULL;
> -	vma_copy->vm_prev = NULL;
> -
> -	return vma_copy;
> -}
> -
> -void exynos_gem_put_vma(struct vm_area_struct *vma)
> -{
> -	if (!vma)
> -		return;
> -
> -	if (vma->vm_ops && vma->vm_ops->close)
> -		vma->vm_ops->close(vma);
> -
> -	if (vma->vm_file)
> -		fput(vma->vm_file);
> -
> -	kfree(vma);
> -}
> -
> -int exynos_gem_get_pages_from_userptr(unsigned long start,
> -						unsigned int npages,
> -						struct page **pages,
> -						struct vm_area_struct *vma)
> -{
> -	int get_npages;
> -
> -	/* the memory region mmaped with VM_PFNMAP. */
> -	if (vma_is_io(vma)) {
> -		unsigned int i;
> -
> -		for (i = 0; i < npages; ++i, start += PAGE_SIZE) {
> -			unsigned long pfn;
> -			int ret = follow_pfn(vma, start, &pfn);
> -			if (ret)
> -				return ret;
> -
> -			pages[i] = pfn_to_page(pfn);
> -		}
> -
> -		if (i != npages) {
> -			DRM_ERROR("failed to get user_pages.\n");
> -			return -EINVAL;
> -		}
> -
> -		return 0;
> -	}
> -
> -	get_npages = get_user_pages(current, current->mm, start,
> -					npages, 1, 1, pages, NULL);
> -	get_npages = max(get_npages, 0);
> -	if (get_npages != npages) {
> -		DRM_ERROR("failed to get user_pages.\n");
> -		while (get_npages)
> -			put_page(pages[--get_npages]);
> -		return -EFAULT;
> -	}
> -
> -	return 0;
> -}
> -
> -void exynos_gem_put_pages_to_userptr(struct page **pages,
> -					unsigned int npages,
> -					struct vm_area_struct *vma)
> -{
> -	if (!vma_is_io(vma)) {
> -		unsigned int i;
> -
> -		for (i = 0; i < npages; i++) {
> -			set_page_dirty_lock(pages[i]);
> -
> -			/*
> -			 * undo the reference we took when populating
> -			 * the table.
> -			 */
> -			put_page(pages[i]);
> -		}
> -	}
> -}
> -
>  int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
>  				struct sg_table *sgt,
>  				enum dma_data_direction dir)
>
diff mbox

Patch

diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 81a250830808..265519c0fe2d 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
@@ -190,10 +190,8 @@  struct g2d_cmdlist_userptr {
 	dma_addr_t		dma_addr;
 	unsigned long		userptr;
 	unsigned long		size;
-	struct page		**pages;
-	unsigned int		npages;
+	struct frame_vector	*vec;
 	struct sg_table		*sgt;
-	struct vm_area_struct	*vma;
 	atomic_t		refcount;
 	bool			in_pool;
 	bool			out_of_list;
@@ -363,6 +361,7 @@  static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev,
 {
 	struct g2d_cmdlist_userptr *g2d_userptr =
 					(struct g2d_cmdlist_userptr *)obj;
+	struct page **pages;
 
 	if (!obj)
 		return;
@@ -382,19 +381,21 @@  out:
 	exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt,
 					DMA_BIDIRECTIONAL);
 
-	exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
-					g2d_userptr->npages,
-					g2d_userptr->vma);
+	pages = frame_vector_pages(g2d_userptr->vec);
+	if (!IS_ERR(pages)) {
+		int i;
 
-	exynos_gem_put_vma(g2d_userptr->vma);
+		for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++)
+			set_page_dirty_lock(pages[i]);
+	}
+	put_vaddr_frames(g2d_userptr->vec);
+	frame_vector_destroy(g2d_userptr->vec);
 
 	if (!g2d_userptr->out_of_list)
 		list_del_init(&g2d_userptr->list);
 
 	sg_free_table(g2d_userptr->sgt);
 	kfree(g2d_userptr->sgt);
-
-	drm_free_large(g2d_userptr->pages);
 	kfree(g2d_userptr);
 }
 
@@ -413,6 +414,7 @@  static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
 	struct vm_area_struct *vma;
 	unsigned long start, end;
 	unsigned int npages, offset;
+	struct frame_vector *vec;
 	int ret;
 
 	if (!size) {
@@ -456,65 +458,37 @@  static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
 		return ERR_PTR(-ENOMEM);
 
 	atomic_set(&g2d_userptr->refcount, 1);
+	g2d_userptr->size = size;
 
 	start = userptr & PAGE_MASK;
 	offset = userptr & ~PAGE_MASK;
 	end = PAGE_ALIGN(userptr + size);
 	npages = (end - start) >> PAGE_SHIFT;
-	g2d_userptr->npages = npages;
-
-	pages = drm_calloc_large(npages, sizeof(struct page *));
-	if (!pages) {
-		DRM_ERROR("failed to allocate pages.\n");
-		ret = -ENOMEM;
+	vec = g2d_userptr->vec = frame_vector_create(npages);
+	if (!vec)
 		goto err_free;
-	}
 
-	down_read(&current->mm->mmap_sem);
-	vma = find_vma(current->mm, userptr);
-	if (!vma) {
-		up_read(&current->mm->mmap_sem);
-		DRM_ERROR("failed to get vm region.\n");
+	ret = get_vaddr_frames(start, npages, 1, 1, vec);
+	if (ret != npages) {
+		DRM_ERROR("failed to get user pages from userptr.\n");
+		if (ret < 0)
+			goto err_destroy_framevec;
 		ret = -EFAULT;
-		goto err_free_pages;
+		goto err_put_framevec;
 	}
-
-	if (vma->vm_end < userptr + size) {
-		up_read(&current->mm->mmap_sem);
-		DRM_ERROR("vma is too small.\n");
+	if (frame_vector_to_pages(vec) < 0) {
 		ret = -EFAULT;
-		goto err_free_pages;
+		goto err_put_framevec;
 	}
 
-	g2d_userptr->vma = exynos_gem_get_vma(vma);
-	if (!g2d_userptr->vma) {
-		up_read(&current->mm->mmap_sem);
-		DRM_ERROR("failed to copy vma.\n");
-		ret = -ENOMEM;
-		goto err_free_pages;
-	}
-
-	g2d_userptr->size = size;
-
-	ret = exynos_gem_get_pages_from_userptr(start & PAGE_MASK,
-						npages, pages, vma);
-	if (ret < 0) {
-		up_read(&current->mm->mmap_sem);
-		DRM_ERROR("failed to get user pages from userptr.\n");
-		goto err_put_vma;
-	}
-
-	up_read(&current->mm->mmap_sem);
-	g2d_userptr->pages = pages;
-
 	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
 	if (!sgt) {
 		ret = -ENOMEM;
-		goto err_free_userptr;
+		goto err_put_framevec;
 	}
 
-	ret = sg_alloc_table_from_pages(sgt, pages, npages, offset,
-					size, GFP_KERNEL);
+	ret = sg_alloc_table_from_pages(sgt, frame_vector_pages(vec), npages,
+					offset, size, GFP_KERNEL);
 	if (ret < 0) {
 		DRM_ERROR("failed to get sgt from pages.\n");
 		goto err_free_sgt;
@@ -549,16 +523,11 @@  err_sg_free_table:
 err_free_sgt:
 	kfree(sgt);
 
-err_free_userptr:
-	exynos_gem_put_pages_to_userptr(g2d_userptr->pages,
-					g2d_userptr->npages,
-					g2d_userptr->vma);
-
-err_put_vma:
-	exynos_gem_put_vma(g2d_userptr->vma);
+err_put_framevec:
+	put_vaddr_frames(vec);
 
-err_free_pages:
-	drm_free_large(pages);
+err_destroy_framevec:
+	frame_vector_destroy(vec);
 
 err_free:
 	kfree(g2d_userptr);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 0d5b9698d384..47068ae44ced 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -378,103 +378,6 @@  int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
 	return 0;
 }
 
-struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma)
-{
-	struct vm_area_struct *vma_copy;
-
-	vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
-	if (!vma_copy)
-		return NULL;
-
-	if (vma->vm_ops && vma->vm_ops->open)
-		vma->vm_ops->open(vma);
-
-	if (vma->vm_file)
-		get_file(vma->vm_file);
-
-	memcpy(vma_copy, vma, sizeof(*vma));
-
-	vma_copy->vm_mm = NULL;
-	vma_copy->vm_next = NULL;
-	vma_copy->vm_prev = NULL;
-
-	return vma_copy;
-}
-
-void exynos_gem_put_vma(struct vm_area_struct *vma)
-{
-	if (!vma)
-		return;
-
-	if (vma->vm_ops && vma->vm_ops->close)
-		vma->vm_ops->close(vma);
-
-	if (vma->vm_file)
-		fput(vma->vm_file);
-
-	kfree(vma);
-}
-
-int exynos_gem_get_pages_from_userptr(unsigned long start,
-						unsigned int npages,
-						struct page **pages,
-						struct vm_area_struct *vma)
-{
-	int get_npages;
-
-	/* the memory region mmaped with VM_PFNMAP. */
-	if (vma_is_io(vma)) {
-		unsigned int i;
-
-		for (i = 0; i < npages; ++i, start += PAGE_SIZE) {
-			unsigned long pfn;
-			int ret = follow_pfn(vma, start, &pfn);
-			if (ret)
-				return ret;
-
-			pages[i] = pfn_to_page(pfn);
-		}
-
-		if (i != npages) {
-			DRM_ERROR("failed to get user_pages.\n");
-			return -EINVAL;
-		}
-
-		return 0;
-	}
-
-	get_npages = get_user_pages(current, current->mm, start,
-					npages, 1, 1, pages, NULL);
-	get_npages = max(get_npages, 0);
-	if (get_npages != npages) {
-		DRM_ERROR("failed to get user_pages.\n");
-		while (get_npages)
-			put_page(pages[--get_npages]);
-		return -EFAULT;
-	}
-
-	return 0;
-}
-
-void exynos_gem_put_pages_to_userptr(struct page **pages,
-					unsigned int npages,
-					struct vm_area_struct *vma)
-{
-	if (!vma_is_io(vma)) {
-		unsigned int i;
-
-		for (i = 0; i < npages; i++) {
-			set_page_dirty_lock(pages[i]);
-
-			/*
-			 * undo the reference we took when populating
-			 * the table.
-			 */
-			put_page(pages[i]);
-		}
-	}
-}
-
 int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
 				struct sg_table *sgt,
 				enum dma_data_direction dir)