diff options
Diffstat (limited to 'drivers/gpu/drm/drm_prime.c')
| -rw-r--r-- | drivers/gpu/drm/drm_prime.c | 70 |
1 files changed, 55 insertions, 15 deletions
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index acb5c5b58f7..1e54b22f8f0 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -193,11 +193,8 @@ static void drm_gem_dmabuf_release(struct dma_buf *dma_buf) { struct drm_gem_object *obj = dma_buf->priv; - if (obj->export_dma_buf == dma_buf) { - /* drop the reference on the export fd holds */ - obj->export_dma_buf = NULL; - drm_gem_object_unreference_unlocked(obj); - } + /* drop the reference on the export fd holds */ + drm_gem_object_unreference_unlocked(obj); } static void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf) @@ -298,6 +295,37 @@ struct dma_buf *drm_gem_prime_export(struct drm_device *dev, } EXPORT_SYMBOL(drm_gem_prime_export); +static struct dma_buf *export_and_register_object(struct drm_device *dev, + struct drm_gem_object *obj, + uint32_t flags) +{ + struct dma_buf *dmabuf; + + /* prevent races with concurrent gem_close. */ + if (obj->handle_count == 0) { + dmabuf = ERR_PTR(-ENOENT); + return dmabuf; + } + + dmabuf = dev->driver->gem_prime_export(dev, obj, flags); + if (IS_ERR(dmabuf)) { + /* normally the created dma-buf takes ownership of the ref, + * but if that fails then drop the ref + */ + return dmabuf; + } + + /* + * Note that callers do not need to clean up the export cache + * since the check for obj->handle_count guarantees that someone + * will clean it up. + */ + obj->dma_buf = dmabuf; + get_dma_buf(obj->dma_buf); + + return dmabuf; +} + int drm_gem_prime_handle_to_fd(struct drm_device *dev, struct drm_file *file_priv, uint32_t handle, uint32_t flags, int *prime_fd) @@ -313,15 +341,20 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev, /* re-export the original imported object */ if (obj->import_attach) { dmabuf = obj->import_attach->dmabuf; + get_dma_buf(dmabuf); goto out_have_obj; } - if (obj->export_dma_buf) { - dmabuf = obj->export_dma_buf; + mutex_lock(&dev->object_name_lock); + if (obj->dma_buf) { + get_dma_buf(obj->dma_buf); + dmabuf = obj->dma_buf; + mutex_unlock(&dev->object_name_lock); goto out_have_obj; } - dmabuf = dev->driver->gem_prime_export(dev, obj, flags); + dmabuf = export_and_register_object(dev, obj, flags); + mutex_unlock(&dev->object_name_lock); if (IS_ERR(dmabuf)) { /* normally the created dma-buf takes ownership of the ref, * but if that fails then drop the ref @@ -329,14 +362,13 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev, ret = PTR_ERR(dmabuf); goto out; } - obj->export_dma_buf = dmabuf; mutex_lock(&file_priv->prime.lock); /* if we've exported this buffer the cheat and add it to the import list * so we get the correct handle back */ ret = drm_prime_add_buf_handle(&file_priv->prime, - obj->export_dma_buf, handle); + dmabuf, handle); if (ret) goto fail_put_dmabuf; @@ -349,7 +381,6 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev, return 0; out_have_obj: - get_dma_buf(dmabuf); ret = dma_buf_fd(dmabuf, flags); if (ret < 0) { dma_buf_put(dmabuf); @@ -365,8 +396,6 @@ fail_rm_handle: dmabuf); mutex_unlock(&file_priv->prime.lock); fail_put_dmabuf: - /* clear NOT to be checked when releasing dma_buf */ - obj->export_dma_buf = NULL; dma_buf_put(dmabuf); out: drm_gem_object_unreference_unlocked(obj); @@ -448,13 +477,22 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev, goto out_put; /* never seen this one, need to import */ + mutex_lock(&dev->object_name_lock); obj = dev->driver->gem_prime_import(dev, dma_buf); if (IS_ERR(obj)) { ret = PTR_ERR(obj); - goto out_put; + goto out_unlock; + } + + if (obj->dma_buf) { + WARN_ON(obj->dma_buf != dma_buf); + } else { + obj->dma_buf = dma_buf; + get_dma_buf(dma_buf); } - ret = drm_gem_handle_create(file_priv, obj, handle); + /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */ + ret = drm_gem_handle_create_tail(file_priv, obj, handle); drm_gem_object_unreference_unlocked(obj); if (ret) goto out_put; @@ -475,6 +513,8 @@ fail: * to detach.. which seems ok.. */ drm_gem_handle_delete(file_priv, *handle); +out_unlock: + mutex_lock(&dev->object_name_lock); out_put: dma_buf_put(dma_buf); mutex_unlock(&file_priv->prime.lock); |