On Wed, Nov 22, 2023 at 7:25 AM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
>
> Modern DRM drivers acquire ioctl locks by themselves. Legacy ioctls
> for user-space mode setting used to acquire drm_global_mutex. After
> removing the ioctl entry points, also remove the locking code. The only
> legacy ioctl without global locking was VBLANK_WAIT, which has been
> removed as well. Hence remove the related DRM_UNLOCKED flag.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
> ---
> drivers/gpu/drm/drm_ioc32.c | 2 +-
> drivers/gpu/drm/drm_ioctl.c | 23 +++++++----------------
> include/drm/drm_ioctl.h | 11 -----------
> 3 files changed, 8 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c
> index 910cadf14756e..129e2b91dbfe7 100644
> --- a/drivers/gpu/drm/drm_ioc32.c
> +++ b/drivers/gpu/drm/drm_ioc32.c
> @@ -273,7 +273,7 @@ static int compat_drm_wait_vblank(struct file *file, unsigned int cmd,
> req.request.type = req32.request.type;
> req.request.sequence = req32.request.sequence;
> req.request.signal = req32.request.signal;
> - err = drm_ioctl_kernel(file, drm_wait_vblank_ioctl, &req, DRM_UNLOCKED);
> + err = drm_ioctl_kernel(file, drm_wait_vblank_ioctl, &req, 0);
>
> req32.reply.type = req.reply.type;
> req32.reply.sequence = req.reply.sequence;
> diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
> index 9c6326b908e74..1cf1de342d6aa 100644
> --- a/drivers/gpu/drm/drm_ioctl.c
> +++ b/drivers/gpu/drm/drm_ioctl.c
> @@ -583,7 +583,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
>
> DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
>
> - DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, DRM_UNLOCKED),
> + DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),
>
> DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
>
> @@ -716,7 +716,7 @@ long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
> {
> struct drm_file *file_priv = file->private_data;
> struct drm_device *dev = file_priv->minor->dev;
> - int retcode;
> + int ret;
>
> /* Update drm_file owner if fd was passed along. */
> drm_file_update_pid(file_priv);
> @@ -724,20 +724,11 @@ long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
> if (drm_dev_is_unplugged(dev))
> return -ENODEV;
>
> - retcode = drm_ioctl_permit(flags, file_priv);
> - if (unlikely(retcode))
> - return retcode;
> -
> - /* Enforce sane locking for modern driver ioctls. */
> - if (likely(!drm_core_check_feature(dev, DRIVER_LEGACY)) ||
> - (flags & DRM_UNLOCKED))
> - retcode = func(dev, kdata, file_priv);
> - else {
> - mutex_lock(&drm_global_mutex);
> - retcode = func(dev, kdata, file_priv);
> - mutex_unlock(&drm_global_mutex);
> - }
> - return retcode;
> + ret = drm_ioctl_permit(flags, file_priv);
> + if (unlikely(ret))
> + return ret;
> +
> + return func(dev, kdata, file_priv);
> }
> EXPORT_SYMBOL(drm_ioctl_kernel);
>
> diff --git a/include/drm/drm_ioctl.h b/include/drm/drm_ioctl.h
> index 6ed61c371f6ce..171760b6c4a14 100644
> --- a/include/drm/drm_ioctl.h
> +++ b/include/drm/drm_ioctl.h
> @@ -109,17 +109,6 @@ enum drm_ioctl_flags {
> * This is equivalent to callers with the SYSADMIN capability.
> */
> DRM_ROOT_ONLY = BIT(2),
> - /**
> - * @DRM_UNLOCKED:
> - *
> - * Whether &drm_ioctl_desc.func should be called with the DRM BKL held
> - * or not. Enforced as the default for all modern drivers, hence there
> - * should never be a need to set this flag.
> - *
> - * Do not use anywhere else than for the VBLANK_WAIT IOCTL, which is the
> - * only legacy IOCTL which needs this.
> - */
> - DRM_UNLOCKED = BIT(4),
> /**
> * @DRM_RENDER_ALLOW:
> *
> --
> 2.42.1
>
