diff options
| -rw-r--r-- | drivers/gpu/drm/drm_atomic.c | 21 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_atomic_helper.c | 21 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_connector.c | 11 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp_mst.c | 8 | ||||
| -rw-r--r-- | include/drm/drm_connector.h | 71 |
5 files changed, 99 insertions, 33 deletions
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 1a4b44923aec..281cf9cbb44c 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -1702,27 +1702,6 @@ drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state, struct drm_connector *connector = conn_state->connector; struct drm_crtc_state *crtc_state; - /* - * For compatibility with legacy users, we want to make sure that - * we allow DPMS On<->Off modesets on unregistered connectors, since - * legacy modesetting users will not be expecting these to fail. We do - * not however, want to allow legacy users to assign a connector - * that's been unregistered from sysfs to another CRTC, since doing - * this with a now non-existent connector could potentially leave us - * in an invalid state. - * - * Since the connector can be unregistered at any point during an - * atomic check or commit, this is racy. But that's OK: all we care - * about is ensuring that userspace can't use this connector for new - * configurations after it's been notified that the connector is no - * longer present. - */ - if (!READ_ONCE(connector->registered) && crtc) { - DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n", - connector->base.id, connector->name); - return -EINVAL; - } - if (conn_state->crtc == crtc) return 0; diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index c22062cc9992..d24a15484e31 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -307,6 +307,26 @@ update_connector_routing(struct drm_atomic_state *state, return 0; } + crtc_state = drm_atomic_get_new_crtc_state(state, + new_connector_state->crtc); + /* + * For compatibility with legacy users, we want to make sure that + * we allow DPMS On->Off modesets on unregistered connectors. Modesets + * which would result in anything else must be considered invalid, to + * avoid turning on new displays on dead connectors. + * + * Since the connector can be unregistered at any point during an + * atomic check or commit, this is racy. But that's OK: all we care + * about is ensuring that userspace can't do anything but shut off the + * display on a connector that was destroyed after its been notified, + * not before. + */ + if (drm_connector_is_unregistered(connector) && crtc_state->active) { + DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n", + connector->base.id, connector->name); + return -EINVAL; + } + funcs = connector->helper_private; if (funcs->atomic_best_encoder) @@ -351,7 +371,6 @@ update_connector_routing(struct drm_atomic_state *state, set_best_encoder(state, new_connector_state, new_encoder); - crtc_state = drm_atomic_get_new_crtc_state(state, new_connector_state->crtc); crtc_state->connectors_changed = true; DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n", diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index 6011d769d50b..7bb68ca4aa0b 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -375,7 +375,8 @@ void drm_connector_cleanup(struct drm_connector *connector) /* The connector should have been removed from userspace long before * it is finally destroyed. */ - if (WARN_ON(connector->registered)) + if (WARN_ON(connector->registration_state == + DRM_CONNECTOR_REGISTERED)) drm_connector_unregister(connector); if (connector->tile_group) { @@ -432,7 +433,7 @@ int drm_connector_register(struct drm_connector *connector) return 0; mutex_lock(&connector->mutex); - if (connector->registered) + if (connector->registration_state != DRM_CONNECTOR_INITIALIZING) goto unlock; ret = drm_sysfs_connector_add(connector); @@ -452,7 +453,7 @@ int drm_connector_register(struct drm_connector *connector) drm_mode_object_register(connector->dev, &connector->base); - connector->registered = true; + connector->registration_state = DRM_CONNECTOR_REGISTERED; goto unlock; err_debugfs: @@ -474,7 +475,7 @@ EXPORT_SYMBOL(drm_connector_register); void drm_connector_unregister(struct drm_connector *connector) { mutex_lock(&connector->mutex); - if (!connector->registered) { + if (connector->registration_state != DRM_CONNECTOR_REGISTERED) { mutex_unlock(&connector->mutex); return; } @@ -485,7 +486,7 @@ void drm_connector_unregister(struct drm_connector *connector) drm_sysfs_connector_remove(connector); drm_debugfs_connector_remove(connector); - connector->registered = false; + connector->registration_state = DRM_CONNECTOR_UNREGISTERED; mutex_unlock(&connector->mutex); } EXPORT_SYMBOL(drm_connector_unregister); diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index c7d52c66ff29..8a19cfcfc4f1 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -77,7 +77,7 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder, pipe_config->pbn = mst_pbn; /* Zombie connectors can't have VCPI slots */ - if (READ_ONCE(connector->registered)) { + if (!drm_connector_is_unregistered(connector)) { slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr, port, @@ -317,7 +317,7 @@ static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector) struct edid *edid; int ret; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return intel_connector_update_modes(connector, NULL); edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -333,7 +333,7 @@ intel_dp_mst_detect(struct drm_connector *connector, bool force) struct intel_connector *intel_connector = to_intel_connector(connector); struct intel_dp *intel_dp = intel_connector->mst_port; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return connector_status_disconnected; return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -376,7 +376,7 @@ intel_dp_mst_mode_valid(struct drm_connector *connector, int bpp = 24; /* MST uses fixed bpp */ int max_rate, mode_rate, max_lanes, max_link_clock; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return MODE_ERROR; if (mode->flags & DRM_MODE_FLAG_DBLSCAN) diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 97ea41dc678f..e5f641cdab5a 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -81,6 +81,53 @@ enum drm_connector_status { connector_status_unknown = 3, }; +/** + * enum drm_connector_registration_status - userspace registration status for + * a &drm_connector + * + * This enum is used to track the status of initializing a connector and + * registering it with userspace, so that DRM can prevent bogus modesets on + * connectors that no longer exist. + */ +enum drm_connector_registration_state { + /** + * @DRM_CONNECTOR_INITIALIZING: The connector has just been created, + * but has yet to be exposed to userspace. There should be no + * additional restrictions to how the state of this connector may be + * modified. + */ + DRM_CONNECTOR_INITIALIZING = 0, + + /** + * @DRM_CONNECTOR_REGISTERED: The connector has been fully initialized + * and registered with sysfs, as such it has been exposed to + * userspace. There should be no additional restrictions to how the + * state of this connector may be modified. + */ + DRM_CONNECTOR_REGISTERED = 1, + + /** + * @DRM_CONNECTOR_UNREGISTERED: The connector has either been exposed + * to userspace and has since been unregistered and removed from + * userspace, or the connector was unregistered before it had a chance + * to be exposed to userspace (e.g. still in the + * @DRM_CONNECTOR_INITIALIZING state). When a connector is + * unregistered, there are additional restrictions to how its state + * may be modified: + * + * - An unregistered connector may only have its DPMS changed from + * On->Off. Once DPMS is changed to Off, it may not be switched back + * to On. + * - Modesets are not allowed on unregistered connectors, unless they + * would result in disabling its assigned CRTCs. This means + * disabling a CRTC on an unregistered connector is OK, but enabling + * one is not. + * - Removing a CRTC from an unregistered connector is OK, but new + * CRTCs may never be assigned to an unregistered connector. + */ + DRM_CONNECTOR_UNREGISTERED = 2, +}; + enum subpixel_order { SubPixelUnknown = 0, SubPixelHorizontalRGB, @@ -852,10 +899,12 @@ struct drm_connector { bool ycbcr_420_allowed; /** - * @registered: Is this connector exposed (registered) with userspace? + * @registration_state: Is this connector initializing, exposed + * (registered) with userspace, or unregistered? + * * Protected by @mutex. */ - bool registered; + enum drm_connector_registration_state registration_state; /** * @modes: @@ -1165,6 +1214,24 @@ static inline void drm_connector_unreference(struct drm_connector *connector) drm_connector_put(connector); } +/** + * drm_connector_is_unregistered - has the connector been unregistered from + * userspace? + * @connector: DRM connector + * + * Checks whether or not @connector has been unregistered from userspace. + * + * Returns: + * True if the connector was unregistered, false if the connector is + * registered or has not yet been registered with userspace. + */ +static inline bool +drm_connector_is_unregistered(struct drm_connector *connector) +{ + return READ_ONCE(connector->registration_state) == + DRM_CONNECTOR_UNREGISTERED; +} + const char *drm_get_connector_status_name(enum drm_connector_status status); const char *drm_get_subpixel_order_name(enum subpixel_order order); const char *drm_get_dpms_name(int val); |