From: Rob Clark robdclark@chromium.org
The obj->lock is sufficient for what we need.
This *does* have the implication that userspace can try to shoot themselves in the foot by racing madvise(DONTNEED) with submit. But the result will be about the same if they did madvise(DONTNEED) before the submit ioctl, ie. they might not get want they want if they race with shrinker. But iova fault handling is robust enough, and userspace is only shooting it's own foot.
Signed-off-by: Rob Clark robdclark@chromium.org --- drivers/gpu/drm/msm/msm_drv.c | 11 ++--------- drivers/gpu/drm/msm/msm_gem.c | 4 +--- drivers/gpu/drm/msm/msm_gem.h | 2 -- 3 files changed, 3 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index 49e6daf30b42..f2d58fe25497 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -912,14 +912,9 @@ static int msm_ioctl_gem_madvise(struct drm_device *dev, void *data, return -EINVAL; }
- ret = mutex_lock_interruptible(&dev->struct_mutex); - if (ret) - return ret; - obj = drm_gem_object_lookup(file, args->handle); if (!obj) { - ret = -ENOENT; - goto unlock; + return -ENOENT; }
ret = msm_gem_madvise(obj, args->madv); @@ -928,10 +923,8 @@ static int msm_ioctl_gem_madvise(struct drm_device *dev, void *data, ret = 0; }
- drm_gem_object_put_locked(obj); + drm_gem_object_put(obj);
-unlock: - mutex_unlock(&dev->struct_mutex); return ret; }
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index b60eaf6266e2..8852c05775dc 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -658,8 +658,6 @@ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv)
msm_gem_lock(obj);
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex)); - if (msm_obj->madv != __MSM_MADV_PURGED) msm_obj->madv = madv;
@@ -676,7 +674,6 @@ void msm_gem_purge(struct drm_gem_object *obj) struct msm_gem_object *msm_obj = to_msm_bo(obj);
WARN_ON(!mutex_is_locked(&dev->struct_mutex)); - WARN_ON(!msm_gem_is_locked(obj)); WARN_ON(!is_purgeable(msm_obj)); WARN_ON(obj->import_attach);
@@ -756,6 +753,7 @@ void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu) struct msm_drm_private *priv = obj->dev->dev_private;
might_sleep(); + WARN_ON(!msm_gem_is_locked(obj)); WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED);
if (!atomic_fetch_inc(&msm_obj->active_count)) { diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h index c12fedf88e85..1f8f5f3d08c0 100644 --- a/drivers/gpu/drm/msm/msm_gem.h +++ b/drivers/gpu/drm/msm/msm_gem.h @@ -188,8 +188,6 @@ static inline bool is_active(struct msm_gem_object *msm_obj)
static inline bool is_purgeable(struct msm_gem_object *msm_obj) { - WARN_ON(!msm_gem_is_locked(&msm_obj->base)); - WARN_ON(!mutex_is_locked(&msm_obj->base.dev->struct_mutex)); return (msm_obj->madv == MSM_MADV_DONTNEED) && msm_obj->sgt && !msm_obj->base.dma_buf && !msm_obj->base.import_attach; }