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

Jan Kara
2015-07-13T14:55:51Z

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/Kconfig | 1 +
drivers/gpu/drm/exynos/exynos_drm_g2d.c | 91 ++++++++++---------------------
drivers/gpu/drm/exynos/exynos_drm_gem.c | 97 ---------------------------------
3 files changed, 30 insertions(+), 159 deletions(-)

diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 43003c4ad80b..b364562dc6c1 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -77,6 +77,7 @@ config DRM_EXYNOS_VIDI
config DRM_EXYNOS_G2D
bool "Exynos DRM G2D"
depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D
+ select FRAME_VECTOR
help
Choose this option if you want to use Exynos G2D for DRM.

diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c
index 81a250830808..1d8d9a508373 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);
}

@@ -408,9 +409,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev,
struct exynos_drm_g2d_private *g2d_priv = file_priv->g2d_priv;
struct g2d_cmdlist_userptr *g2d_userptr;
struct g2d_data *g2d;
- struct page **pages;
struct sg_table *sgt;
- struct vm_area_struct *vma;
unsigned long start, end;
unsigned int npages, offset;
int ret;
@@ -456,65 +455,38 @@ 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;
+ g2d_userptr->vec = frame_vector_create(npages);
+ if (!g2d_userptr->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, true, true, g2d_userptr->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(g2d_userptr->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(g2d_userptr->vec),
+ npages, offset, size, GFP_KERNEL);
if (ret < 0) {
DRM_ERROR("failed to get sgt from pages.\n");
goto err_free_sgt;
@@ -549,16 +521,11 @@ 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(g2d_userptr->vec);

-err_free_pages:
- drm_free_large(pages);
+err_destroy_framevec:
+ frame_vector_destroy(g2d_userptr->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)
--
2.1.4