[Intel-gfx] [PATCH v2 29/37] drm/i915: Introduce DRM_I915_GEM_MMAP_OFFSET

[Chris Wilson]

Quoting Matthew Auld (2019-06-27 21:56:25)
> From: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
> 
> Add a new CPU mmap implementation that allows multiple fault handlers
> that depends on the object's backing pages.
> 
> Note that we multiplex mmap_gtt and mmap_offset through the same ioctl,
> and use the zero extending behaviour of drm to differentiate between
> them, when we inspect the flags.
> 
> Signed-off-by: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/gem/i915_gem_ioctls.h    |  2 ++
>  drivers/gpu/drm/i915/gem/i915_gem_mman.c      | 30 ++++++++++++++++++
>  .../gpu/drm/i915/gem/i915_gem_object_types.h  |  3 ++
>  drivers/gpu/drm/i915/i915_drv.c               |  3 +-
>  include/uapi/drm/i915_drm.h                   | 31 +++++++++++++++++++
>  5 files changed, 68 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ioctls.h b/drivers/gpu/drm/i915/gem/i915_gem_ioctls.h
> index ddc7f2a52b3e..5abd5b2172f2 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ioctls.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ioctls.h
> @@ -30,6 +30,8 @@ int i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
>                         struct drm_file *file);
>  int i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
>                             struct drm_file *file);
> +int i915_gem_mmap_offset_ioctl(struct drm_device *dev, void *data,
> +                              struct drm_file *file_priv);
>  int i915_gem_pread_ioctl(struct drm_device *dev, void *data,
>                          struct drm_file *file);
>  int i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> index 7b46f44d9c20..cbf89e80a97b 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> @@ -536,12 +536,42 @@ i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
>                         struct drm_file *file)
>  {
>         struct drm_i915_gem_mmap_offset *args = data;
> +       struct drm_i915_private *i915 = to_i915(dev);
> +
> +       if (args->flags & I915_MMAP_OFFSET_FLAGS)
> +               return i915_gem_mmap_offset_ioctl(dev, data, file);
> +
> +       if (!HAS_MAPPABLE_APERTURE(i915)) {
> +               DRM_ERROR("No aperture, cannot mmap via legacy GTT\n");
> +               return -ENODEV;
> +       }
>  
>         return __assign_gem_object_mmap_data(file, args->handle,
>                                              I915_MMAP_TYPE_GTT,
>                                              &args->offset);
>  }
>  
> +int i915_gem_mmap_offset_ioctl(struct drm_device *dev, void *data,
> +                              struct drm_file *file)

This seems highly redundant and not correctly plugged in.
-Chris