From e13a058310509b22b2b45cbdd82d8797e173c3db Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed, 5 Jul 2017 06:56:29 +0200
Subject: [PATCH] drm/fb-helper: Stop using mode_config.mutex for internals
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Git-commit: e13a058310509b22b2b45cbdd82d8797e173c3db
Patch-mainline: v4.14-rc1
References: FATE#322643 bsc#1055900
Those are now all protected using fb_helper->lock.
V2: We still need to hold mode_config.mutex right around calling
connector->fill_modes.
V3: I forgot to hold mode_config.mutex while looking at
connector->status and the mode list. Also, we need to patch up the
i915 ->initial_config callback to grab the locks it needs to inspect
the modeset state recovered from the fw.
V4: Don't reorder the probe too much (Ville).
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170705045629.31265-1-daniel.vetter@ffwll.ch
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/drm_fb_helper.c | 33 ++++++++-------------------------
drivers/gpu/drm/drm_vblank.c | 2 +-
drivers/gpu/drm/i915/intel_fbdev.c | 16 ++++++++++++----
3 files changed, 21 insertions(+), 30 deletions(-)
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -106,7 +106,7 @@ static DEFINE_MUTEX(kernel_fb_helper_loc
*/
#define drm_fb_helper_for_each_connector(fbh, i__) \
- for (({ lockdep_assert_held(&(fbh)->dev->mode_config.mutex); }), \
+ for (({ lockdep_assert_held(&(fbh)->lock); }), \
i__ = 0; i__ < (fbh)->connector_count; i__++)
static int __drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
@@ -120,7 +120,6 @@ static int __drm_fb_helper_add_one_conne
return 0;
lockdep_assert_held(&fb_helper->lock);
- lockdep_assert_held(&fb_helper->dev->mode_config.mutex);
count = fb_helper->connector_count + 1;
@@ -152,11 +151,7 @@ int drm_fb_helper_add_one_connector(stru
int err;
mutex_lock(&fb_helper->lock);
- mutex_lock(&fb_helper->dev->mode_config.mutex);
-
err = __drm_fb_helper_add_one_connector(fb_helper, connector);
-
- mutex_unlock(&fb_helper->dev->mode_config.mutex);
mutex_unlock(&fb_helper->lock);
return err;
@@ -188,7 +183,6 @@ int drm_fb_helper_single_add_all_connect
return 0;
mutex_lock(&fb_helper->lock);
- mutex_lock(&dev->mode_config.mutex);
drm_connector_list_iter_begin(dev, &conn_iter);
drm_for_each_connector_iter(connector, &conn_iter) {
ret = __drm_fb_helper_add_one_connector(fb_helper, connector);
@@ -210,7 +204,6 @@ fail:
fb_helper->connector_count = 0;
out:
drm_connector_list_iter_end(&conn_iter);
- mutex_unlock(&dev->mode_config.mutex);
mutex_unlock(&fb_helper->lock);
return ret;
@@ -253,11 +246,7 @@ int drm_fb_helper_remove_one_connector(s
int err;
mutex_lock(&fb_helper->lock);
- mutex_lock(&fb_helper->dev->mode_config.mutex);
-
err = __drm_fb_helper_remove_one_connector(fb_helper, connector);
-
- mutex_unlock(&fb_helper->dev->mode_config.mutex);
mutex_unlock(&fb_helper->lock);
return err;
@@ -1879,12 +1868,11 @@ void drm_fb_helper_fill_var(struct fb_in
EXPORT_SYMBOL(drm_fb_helper_fill_var);
static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
- uint32_t maxX,
- uint32_t maxY)
+ uint32_t maxX,
+ uint32_t maxY)
{
struct drm_connector *connector;
- int count = 0;
- int i;
+ int i, count = 0;
drm_fb_helper_for_each_connector(fb_helper, i) {
connector = fb_helper->connector_info[i]->connector;
@@ -2282,12 +2270,8 @@ static void drm_setup_crtcs(struct drm_f
int i;
DRM_DEBUG_KMS("\n");
- if (drm_fb_helper_probe_connector_modes(fb_helper, width, height) == 0)
- DRM_DEBUG_KMS("No connectors reported connected with modes\n");
-
/* prevent concurrent modification of connector_count by hotplug */
lockdep_assert_held(&fb_helper->lock);
- lockdep_assert_held(&fb_helper->dev->mode_config.mutex);
crtcs = kcalloc(fb_helper->connector_count,
sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
@@ -2302,6 +2286,9 @@ static void drm_setup_crtcs(struct drm_f
goto out;
}
+ mutex_lock(&fb_helper->dev->mode_config.mutex);
+ if (drm_fb_helper_probe_connector_modes(fb_helper, width, height) == 0)
+ DRM_DEBUG_KMS("No connectors reported connected with modes\n");
drm_enable_connectors(fb_helper, enabled);
if (!(fb_helper->funcs->initial_config &&
@@ -2323,6 +2310,7 @@ static void drm_setup_crtcs(struct drm_f
drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
}
+ mutex_unlock(&fb_helper->dev->mode_config.mutex);
/* need to set the modesets up here for use later */
/* fill out the connector<->crtc mappings into the modesets */
@@ -2414,12 +2402,10 @@ int drm_fb_helper_initial_config(struct
return 0;
mutex_lock(&fb_helper->lock);
- mutex_lock(&dev->mode_config.mutex);
drm_setup_crtcs(fb_helper,
dev->mode_config.max_width,
dev->mode_config.max_height);
ret = drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
- mutex_unlock(&dev->mode_config.mutex);
mutex_unlock(&fb_helper->lock);
if (ret)
return ret;
@@ -2482,10 +2468,7 @@ int drm_fb_helper_hotplug_event(struct d
DRM_DEBUG_KMS("\n");
- mutex_lock(&dev->mode_config.mutex);
drm_setup_crtcs(fb_helper, fb_helper->fb->width, fb_helper->fb->height);
-
- mutex_unlock(&dev->mode_config.mutex);
mutex_unlock(&fb_helper->lock);
drm_fb_helper_set_par(fb_helper->fbdev);
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -836,7 +836,7 @@ static void send_vblank_event(struct drm
* NOTE: Drivers using this to send out the &drm_crtc_state.event as part of an
* atomic commit must ensure that the next vblank happens at exactly the same
* time as the atomic commit is committed to the hardware. This function itself
- * does **not** protect again the next vblank interrupt racing with either this
+ * does **not** protect against the next vblank interrupt racing with either this
* function call or the atomic commit operation. A possible sequence could be:
*
* 1. Driver commits new hardware state into vblank-synchronized registers.
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -352,14 +352,20 @@ static bool intel_fb_initial_config(stru
unsigned int count = min(fb_helper->connector_count, BITS_PER_LONG);
int i, j;
bool *save_enabled;
- bool fallback = true;
+ bool fallback = true, ret = true;
int num_connectors_enabled = 0;
int num_connectors_detected = 0;
+ struct drm_modeset_acquire_ctx ctx;
save_enabled = kcalloc(count, sizeof(bool), GFP_KERNEL);
if (!save_enabled)
return false;
+ drm_modeset_acquire_init(&ctx, 0);
+
+ while (drm_modeset_lock_all_ctx(fb_helper->dev, &ctx) != 0)
+ drm_modeset_backoff(&ctx);
+
memcpy(save_enabled, enabled, count);
mask = GENMASK(count - 1, 0);
conn_configured = 0;
@@ -509,12 +515,14 @@ retry:
bail:
DRM_DEBUG_KMS("Not using firmware configuration\n");
memcpy(enabled, save_enabled, count);
- kfree(save_enabled);
- return false;
+ ret = false;
}
+ drm_modeset_drop_locks(&ctx);
+ drm_modeset_acquire_fini(&ctx);
+
kfree(save_enabled);
- return true;
+ return ret;
}
static const struct drm_fb_helper_funcs intel_fb_helper_funcs = {