From: Ankit Nautiyal ankit.k.nautiyal@intel.com
If the user-space does not support aspect-ratio, and requests for a modeset with mode having aspect ratio bits set, then the given user-mode must be rejected. Secondly, while preparing a user-mode from kernel mode, the aspect-ratio info must not be given, if aspect-ratio is not supported by the user.
This patch: 1. rejects the modes with aspect-ratio info, during modeset, if the user does not support aspect ratio. 2. does not load the aspect-ratio info in user-mode structure, if aspect ratio is not supported. 3. adds helper functions for determining if aspect-ratio is expected in user-mode and for allowing/disallowing the aspect-ratio, if its not expected.
Signed-off-by: Ankit Nautiyal ankit.k.nautiyal@intel.com
V3: Addressed review comments from Ville: Do not corrupt the current crtc state by updating aspect-ratio on the fly. V4: rebase V5: As suggested by Ville, rejected the modeset calls for modes with aspect ratio, if the user does not set aspect-ratio cap. V6: Used the helper functions for determining if aspect-ratio is expected in the user-mode. V7: rebase V8: rebase V9: rebase V10: Modified the commit-message V11: rebase V12: Merged the patch for adding aspect-ratio helper functions with this patch. V13: Minor modifications as suggested by Ville. --- drivers/gpu/drm/drm_crtc.c | 8 +++++++ drivers/gpu/drm/drm_crtc_internal.h | 6 +++++ drivers/gpu/drm/drm_modes.c | 47 +++++++++++++++++++++++++++++++++++++ 3 files changed, 61 insertions(+)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index a231dd5..98323f4 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -449,6 +449,7 @@ int drm_mode_getcrtc(struct drm_device *dev, crtc_resp->mode_valid = 0; } } + drm_mode_filter_aspect_ratio_flags(file_priv, &crtc_resp->mode); drm_modeset_unlock(&crtc->mutex);
return 0; @@ -628,6 +629,13 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data, ret = -ENOMEM; goto out; } + if (!drm_mode_aspect_ratio_allowed(file_priv, + &crtc_req->mode)) { + DRM_DEBUG_KMS("Unexpected aspect-ratio flag bits\n"); + ret = -EINVAL; + goto out; + } +
ret = drm_mode_convert_umode(dev, mode, &crtc_req->mode); if (ret) { diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h index 5d307b2..31d6c77 100644 --- a/drivers/gpu/drm/drm_crtc_internal.h +++ b/drivers/gpu/drm/drm_crtc_internal.h @@ -222,3 +222,9 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev, void drm_mode_fixup_1366x768(struct drm_display_mode *mode); void drm_reset_display_info(struct drm_connector *connector); u32 drm_add_display_info(struct drm_connector *connector, const struct edid *edid); + +/* drm_modes.c */ +bool drm_mode_aspect_ratio_allowed(const struct drm_file *file_priv, + struct drm_mode_modeinfo *umode); +void drm_mode_filter_aspect_ratio_flags(const struct drm_file *file_priv, + struct drm_mode_modeinfo *umode); diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index c395a24..2bf2f0b 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -1759,3 +1759,50 @@ bool drm_mode_is_420(const struct drm_display_info *display, drm_mode_is_420_also(display, mode); } EXPORT_SYMBOL(drm_mode_is_420); + +/** + * drm_mode_aspect_ratio_allowed - checks if the aspect-ratio information + * is expected from the user-mode. + * + * If the user has set aspect-ratio cap, then the flag of the user-mode is + * allowed to contain aspect-ratio value. + * If the user does not set aspect-ratio cap, then the only value allowed in the + * flags bits is aspect-ratio NONE. + * + * @file_priv: file private structure to get the user capabilities + * @umode: drm_mode_modeinfo struct, whose flag carry the aspect ratio + * information. + * + * Returns: + * true if the aspect-ratio info is allowed in the user-mode flags. + * false, otherwise. + */ +bool +drm_mode_aspect_ratio_allowed(const struct drm_file *file_priv, + struct drm_mode_modeinfo *umode) +{ + if (file_priv->aspect_ratio_allowed || + (umode->flags & DRM_MODE_FLAG_PIC_AR_MASK) == DRM_MODE_FLAG_PIC_AR_NONE) + return true; + return false; +} + +/** + * drm_mode_filter_aspect_ratio_flags - filters the aspect-ratio bits in the + * user-mode flags. + * + * Checks if the aspect-ratio information is allowed. Resets the aspect-ratio + * bits in the user-mode flags, if aspect-ratio info is not allowed. + * + * @file_priv: file private structure to get the user capabilities. + * @umode: drm_mode_modeinfo struct, whose flags' aspect-ratio bits needs to + * be filtered. + * + */ +void +drm_mode_filter_aspect_ratio_flags(const struct drm_file *file_priv, + struct drm_mode_modeinfo *umode) +{ + if (!drm_mode_aspect_ratio_allowed(file_priv, umode)) + umode->flags &= ~DRM_MODE_FLAG_PIC_AR_MASK; +}