Re: [PATCH v3 5/7] drm/vmwgfx: Inline ttm_bo_mmap() into vmwgfx driver

Am 16.04.21 um 15:31 schrieb Thomas Zimmermann:

The vmwgfx driver is the only remaining user of ttm_bo_mmap(). Inline the code. The internal helper ttm_bo_vm_lookup() is now also part of vmwgfx as vmw_bo_vm_lookup().

v2:

• replace pr_err() with drm_err() (Zack)

Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Reviewed-by: Zack Rusin zackr@vmware.com

---

drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c | 56 ++++++++++++++++++++++-- 1 file changed, 53 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c index cb9975889e2f..c8b6543b4e39 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c @@ -27,6 +27,32 @@

#include "vmwgfx_drv.h"

+static struct ttm_buffer_object *vmw_bo_vm_lookup(struct ttm_device *bdev,

• 				  unsigned long offset,
  

• 				  unsigned long pages)
  

+{

• struct vmw_private *dev_priv = container_of(bdev, struct vmw_private, bdev);
• struct drm_device *drm = &dev_priv->drm;
• struct drm_vma_offset_node *node;
• struct ttm_buffer_object *bo = NULL;
• drm_vma_offset_lock_lookup(bdev->vma_manager);
• node = drm_vma_offset_lookup_locked(bdev->vma_manager, offset, pages);
• if (likely(node)) {

• bo = container_of(node, struct ttm_buffer_object,
  

• 		  base.vma_node);
  

• bo = ttm_bo_get_unless_zero(bo);
  

• }
• drm_vma_offset_unlock_lookup(bdev->vma_manager);
• if (!bo)

• drm_err(drm, "Could not find buffer object to map\n");
  

• return bo;

+}

• int vmw_mmap(struct file *filp, struct vm_area_struct *vma) { static const struct vm_operations_struct vmw_vm_ops = {

@@ -41,10 +67,28 @@ int vmw_mmap(struct file *filp, struct vm_area_struct *vma) }; struct drm_file *file_priv = filp->private_data; struct vmw_private *dev_priv = vmw_priv(file_priv->minor->dev);

• int ret = ttm_bo_mmap(filp, vma, &dev_priv->bdev);

• struct ttm_device *bdev = &dev_priv->bdev;
• struct ttm_buffer_object *bo;
• int ret;
• if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET_START))

• return -EINVAL;
  

• bo = vmw_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
• if (unlikely(!bo))

• return -EINVAL;
  
  

• if (ret)

• return ret;
  

• if (unlikely(!bo->bdev->funcs->verify_access)) {

• ret = -EPERM;
  

• goto out_unref;
  

• }
• ret = bo->bdev->funcs->verify_access(bo, filp);

Is there any reason we can't call vmw_verify_access() directly here?

Would allow us to completely nuke the verify_access callback as well as far as I can see.

Regards, Christian.

• if (unlikely(ret != 0))

• goto out_unref;
  

• ret = ttm_bo_mmap_obj(vma, bo);

• if (unlikely(ret != 0))

• goto out_unref;
  
  

  vma->vm_ops = &vmw_vm_ops;

@@ -52,7 +96,13 @@ int vmw_mmap(struct file *filp, struct vm_area_struct *vma) if (!is_cow_mapping(vma->vm_flags)) vma->vm_flags = (vma->vm_flags & ~VM_MIXEDMAP) | VM_PFNMAP;

• ttm_bo_put(bo); /* release extra ref taken by ttm_bo_mmap_obj() */
• return 0;

+out_unref:

• ttm_bo_put(bo);

• return ret; }

  /* struct vmw_validation_mem callback */