diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2013-08-27 16:12:57 -0400 |
|---|---|---|
| committer | Ben Skeggs <bskeggs@redhat.com> | 2013-11-08 15:36:03 +1000 |
| commit | ac51bb09837098c422a8825bc155ccd736b9632d (patch) | |
| tree | acea0f5016b1376a64ac42222655c8ef67f98153 | |
| parent | 019255797db627f729edbf3885ea4e248a75e0d5 (diff) | |
drm/nouveau/core: Allow asymmetric nouveau_event_get/_put
Most nouveau event handlers have storage in 'static' containers
(structures with lifetimes nearly equivalent to the drm_device),
but are dangerously reused via nouveau_event_get/_put. For
example, if nouveau_event_get is called more than once for a
given handler, the event handler list will be corrupted.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
| -rw-r--r-- | drivers/gpu/drm/nouveau/core/core/event.c | 20 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/core/include/core/event.h | 4 | ||||
| -rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_drm.c | 8 |
3 files changed, 18 insertions, 14 deletions
diff --git a/drivers/gpu/drm/nouveau/core/core/event.c b/drivers/gpu/drm/nouveau/core/core/event.c index e69c463e66e2..9393c37b71c9 100644 --- a/drivers/gpu/drm/nouveau/core/core/event.c +++ b/drivers/gpu/drm/nouveau/core/core/event.c @@ -27,11 +27,13 @@ static void nouveau_event_put_locked(struct nouveau_event *event, int index, struct nouveau_eventh *handler) { - if (!--event->index[index].refs) { - if (event->disable) - event->disable(event, index); + if (__test_and_clear_bit(NVKM_EVENT_ENABLE, &handler->flags)) { + if (!--event->index[index].refs) { + if (event->disable) + event->disable(event, index); + } + list_del(&handler->head); } - list_del(&handler->head); } void @@ -58,10 +60,12 @@ nouveau_event_get(struct nouveau_event *event, int index, return; spin_lock_irqsave(&event->lock, flags); - list_add(&handler->head, &event->index[index].list); - if (!event->index[index].refs++) { - if (event->enable) - event->enable(event, index); + if (!__test_and_set_bit(NVKM_EVENT_ENABLE, &handler->flags)) { + list_add(&handler->head, &event->index[index].list); + if (!event->index[index].refs++) { + if (event->enable) + event->enable(event, index); + } } spin_unlock_irqrestore(&event->lock, flags); } diff --git a/drivers/gpu/drm/nouveau/core/include/core/event.h b/drivers/gpu/drm/nouveau/core/include/core/event.h index ad4d8c283d5f..cb2f632cb3a5 100644 --- a/drivers/gpu/drm/nouveau/core/include/core/event.h +++ b/drivers/gpu/drm/nouveau/core/include/core/event.h @@ -5,8 +5,12 @@ #define NVKM_EVENT_DROP 0 #define NVKM_EVENT_KEEP 1 +/* nouveau_eventh.flags bit #s */ +#define NVKM_EVENT_ENABLE 0 + struct nouveau_eventh { struct list_head head; + unsigned long flags; void *priv; int (*func)(struct nouveau_eventh *, int index); }; diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index 20626b93130c..42e30e256cdc 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -95,7 +95,6 @@ nouveau_drm_vblank_enable(struct drm_device *dev, int head) if (WARN_ON_ONCE(head >= ARRAY_SIZE(drm->vblank))) return -EIO; - WARN_ON_ONCE(drm->vblank[head].func); drm->vblank[head].func = nouveau_drm_vblank_handler; nouveau_event_get(pdisp->vblank, head, &drm->vblank[head]); return 0; @@ -106,11 +105,8 @@ nouveau_drm_vblank_disable(struct drm_device *dev, int head) { struct nouveau_drm *drm = nouveau_drm(dev); struct nouveau_disp *pdisp = nouveau_disp(drm->device); - if (drm->vblank[head].func) - nouveau_event_put(pdisp->vblank, head, &drm->vblank[head]); - else - WARN_ON_ONCE(1); - drm->vblank[head].func = NULL; + + nouveau_event_put(pdisp->vblank, head, &drm->vblank[head]); } static u64 |