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charset="utf-8" From: Rob Herring Introduce a new flag, DRM_MODE_DUMB_KERNEL_MAP, for struct drm_mode_create_dumb. This flag is for internal kernel use to indicate if dumb buffer allocation needs a kernel mapping. This is needed only for GEM DMA where creating a kernel mapping or not has to be decided at allocation time because creating a mapping on demand (with vmap()) is not guaranteed to work. Several drivers are using reimplementing the GEM DMA helpers because they distinguish between kernel and userspace allocations to create a kernel mapping or not. Adding a flag allows migrating these drivers to the helpers while preserving their existing behavior. These include exynos, rockchip, and previously mediatek. Update the callers of drm_mode_dumb_create() to set drm_mode_dumb_create.flags to appropriate defaults. Currently, flags can be set to anything by userspace, but is unused within the kernel. Let's force flags to zero (no kernel mapping) for userspace callers by default. For in kernel clients, set DRM_MODE_DUMB_KERNEL_MAP by default. Drivers can override this as needed. Signed-off-by: Rob Herring [wenst@chromium.org: Emit warning (once) if args->flags is not zero] [wenst@chromium.org: Moved flag def. to include/drm/drm_dumb_buffers.h] Signed-off-by: Chen-Yu Tsai --- Changes since v2: - Switched to drm_warn_once() - Moved flag definition from include/uapi/ to include/drm/drm_dumb_buffers.h - Reworded commit message Changes since v1: - Emit warning if args->flags is not zero --- drivers/gpu/drm/drm_client.c | 2 ++ drivers/gpu/drm/drm_dumb_buffers.c | 4 ++++ include/drm/drm_dumb_buffers.h | 3 +++ 3 files changed, 9 insertions(+) diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c index 46c465bce98c..3d3e61823cc1 100644 --- a/drivers/gpu/drm/drm_client.c +++ b/drivers/gpu/drm/drm_client.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -404,6 +405,7 @@ drm_client_buffer_create_dumb(struct drm_client_dev *cl= ient, u32 width, u32 heig dumb_args.width =3D width; dumb_args.height =3D height; dumb_args.bpp =3D drm_format_info_bpp(info, 0); + dumb_args.flags =3D DRM_MODE_DUMB_KERNEL_MAP; ret =3D drm_mode_create_dumb(dev, &dumb_args, client->file); if (ret) return ERR_PTR(ret); diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_= buffers.c index e2b62e5fb891..60f4c2d08641 100644 --- a/drivers/gpu/drm/drm_dumb_buffers.c +++ b/drivers/gpu/drm/drm_dumb_buffers.c @@ -233,6 +233,10 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev, struct drm_mode_create_dumb *args =3D data; int err; =20 + if (args->flags) + drm_warn_once(dev, "drm_mode_create_dumb.flags is not zero.\n"); + args->flags =3D 0; + err =3D drm_mode_create_dumb(dev, args, file_priv); if (err) { args->handle =3D 0; diff --git a/include/drm/drm_dumb_buffers.h b/include/drm/drm_dumb_buffers.h index 1f3a8236fb3d..4657e44533f4 100644 --- a/include/drm/drm_dumb_buffers.h +++ b/include/drm/drm_dumb_buffers.h @@ -6,6 +6,9 @@ struct drm_device; struct drm_mode_create_dumb; =20 +/* drm_mode_create_dumb flags for internal use */ +#define DRM_MODE_DUMB_KERNEL_MAP (1<<0) + int drm_mode_size_dumb(struct drm_device *dev, struct drm_mode_create_dumb *args, unsigned long hw_pitch_align, --=20 2.53.0.1018.g2bb0e51243-goog