Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fcf93f69 authored by Daniel Vetter's avatar Daniel Vetter Committed by Dave Airlie
Browse files

drm: More specific locking for get* ioctls 



Motivated by the per-plane locking I've gone through all the get*
ioctls and reduced the locking to the bare minimum required.

v2: Rebase and make it compile ...

v3: Review from Sean:
- Simplify return handling in getplane_res.
- Add a comment to getplane_res that the plane list is invariant and
  can be walked locklessly.

v4: Actually git add.

Cc: Sean Paul <seanpaul@chromium.org>
Reviewed-by: default avatarSean Paul <seanpaul@chromium.org>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent 4d02e2de

drivers/gpu/drm/drm_crtc.c

+23 −35
Original line number Diff line number Diff line
@@ -1743,7 +1743,9 @@ int drm_mode_getresources(struct drm_device *dev, void *data, 
	card_res->count_fbs = fb_count;

	mutex_unlock(&file_priv->fbs_lock);



	drm_modeset_lock_all(dev);

	/* mode_config.mutex protects the connector list against e.g. DP MST

	 * connector hot-adding. CRTC/Plane lists are invariant. */

	mutex_lock(&dev->mode_config.mutex);

	if (!drm_is_primary_client(file_priv)) {



		mode_group = NULL;
@@ -1863,7 +1865,7 @@ int drm_mode_getresources(struct drm_device *dev, void *data, 
		  card_res->count_connectors, card_res->count_encoders);



out:

	drm_modeset_unlock_all(dev);

	mutex_unlock(&dev->mode_config.mutex);

	return ret;

}
@@ -1890,14 +1892,11 @@ int drm_mode_getcrtc(struct drm_device *dev, 
	if (!drm_core_check_feature(dev, DRIVER_MODESET))

		return -EINVAL;



	drm_modeset_lock_all(dev);



	crtc = drm_crtc_find(dev, crtc_resp->crtc_id);

	if (!crtc) {

		ret = -ENOENT;

		goto out;

	}

	if (!crtc)

		return -ENOENT;



	drm_modeset_lock_crtc(crtc, crtc->primary);

	crtc_resp->x = crtc->x;

	crtc_resp->y = crtc->y;

	crtc_resp->gamma_size = crtc->gamma_size;
@@ -1914,9 +1913,8 @@ int drm_mode_getcrtc(struct drm_device *dev, 
	} else {

		crtc_resp->mode_valid = 0;

	}

	drm_modeset_unlock_crtc(crtc);



out:

	drm_modeset_unlock_all(dev);

	return ret;

}
@@ -2100,24 +2098,22 @@ int drm_mode_getencoder(struct drm_device *dev, void *data, 
	if (!drm_core_check_feature(dev, DRIVER_MODESET))

		return -EINVAL;



	drm_modeset_lock_all(dev);

	encoder = drm_encoder_find(dev, enc_resp->encoder_id);

	if (!encoder) {

		ret = -ENOENT;

		goto out;

	}

	if (!encoder)

		return -ENOENT;



	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);

	if (encoder->crtc)

		enc_resp->crtc_id = encoder->crtc->base.id;

	else

		enc_resp->crtc_id = 0;

	drm_modeset_unlock(&dev->mode_config.connection_mutex);



	enc_resp->encoder_type = encoder->encoder_type;

	enc_resp->encoder_id = encoder->base.id;

	enc_resp->possible_crtcs = encoder->possible_crtcs;

	enc_resp->possible_clones = encoder->possible_clones;



out:

	drm_modeset_unlock_all(dev);

	return ret;

}
@@ -2141,13 +2137,12 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data, 
	struct drm_mode_config *config;

	struct drm_plane *plane;

	uint32_t __user *plane_ptr;

	int copied = 0, ret = 0;

	int copied = 0;

	unsigned num_planes;



	if (!drm_core_check_feature(dev, DRIVER_MODESET))

		return -EINVAL;



	drm_modeset_lock_all(dev);

	config = &dev->mode_config;



	if (file_priv->universal_planes)
@@ -2163,6 +2158,7 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data, 
	    (plane_resp->count_planes >= num_planes)) {

		plane_ptr = (uint32_t __user *)(unsigned long)plane_resp->plane_id_ptr;



		/* Plane lists are invariant, no locking needed. */

		list_for_each_entry(plane, &config->plane_list, head) {

			/*

			 * Unless userspace set the 'universal planes'
@@ -2172,18 +2168,14 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data, 
			    !file_priv->universal_planes)

				continue;



			if (put_user(plane->base.id, plane_ptr + copied)) {

				ret = -EFAULT;

				goto out;

			}

			if (put_user(plane->base.id, plane_ptr + copied))

				return -EFAULT;

			copied++;

		}

	}

	plane_resp->count_planes = num_planes;



out:

	drm_modeset_unlock_all(dev);

	return ret;

	return 0;

}



/**
@@ -2210,13 +2202,11 @@ int drm_mode_getplane(struct drm_device *dev, void *data, 
	if (!drm_core_check_feature(dev, DRIVER_MODESET))

		return -EINVAL;



	drm_modeset_lock_all(dev);

	plane = drm_plane_find(dev, plane_resp->plane_id);

	if (!plane) {

		ret = -ENOENT;

		goto out;

	}

	if (!plane)

		return -ENOENT;



	drm_modeset_lock(&plane->mutex, NULL);

	if (plane->crtc)

		plane_resp->crtc_id = plane->crtc->base.id;

	else
@@ -2226,6 +2216,7 @@ int drm_mode_getplane(struct drm_device *dev, void *data, 
		plane_resp->fb_id = plane->fb->base.id;

	else

		plane_resp->fb_id = 0;

	drm_modeset_unlock(&plane->mutex);



	plane_resp->plane_id = plane->base.id;

	plane_resp->possible_crtcs = plane->possible_crtcs;
@@ -2241,14 +2232,11 @@ int drm_mode_getplane(struct drm_device *dev, void *data, 
		if (copy_to_user(format_ptr,

				 plane->format_types,

				 sizeof(uint32_t) * plane->format_count)) {

			ret = -EFAULT;

			goto out;

			return -EFAULT;

		}

	}

	plane_resp->count_format_types = plane->format_count;



out:

	drm_modeset_unlock_all(dev);

	return ret;

}