Add unlocked variants of drm_gem_un/pin() functions. These new helpers
will take care of GEM dma-reservation locking for DRM drivers.
VirtIO-GPU driver will use these helpers to pin shmem framebuffers,
preventing them from eviction during scanout.
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_gem.c | 29 +++++++++++++++++++++++++++++
include/drm/drm_gem.h | 3 +++
2 files changed, 32 insertions(+)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index dbb48fc9dff3..0b8d3da985c7 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -1167,6 +1167,35 @@ void drm_gem_unpin(struct drm_gem_object *obj)
obj->funcs->unpin(obj);
}
+int drm_gem_pin_unlocked(struct drm_gem_object *obj)
+{
+ int ret;
+
+ if (!obj->funcs->pin)
+ return 0;
+
+ ret = dma_resv_lock_interruptible(obj->resv, NULL);
+ if (ret)
+ return ret;
+
+ ret = obj->funcs->pin(obj);
+ dma_resv_unlock(obj->resv);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_gem_pin_unlocked);
+
+void drm_gem_unpin_unlocked(struct drm_gem_object *obj)
+{
+ if (!obj->funcs->unpin)
+ return;
+
+ dma_resv_lock(obj->resv, NULL);
+ obj->funcs->unpin(obj);
+ dma_resv_unlock(obj->resv);
+}
+EXPORT_SYMBOL(drm_gem_unpin_unlocked);
+
int drm_gem_vmap(struct drm_gem_object *obj, struct iosys_map *map)
{
int ret;
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index 8e5c22f25691..6f6d96f79a67 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -493,4 +493,7 @@ unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru,
bool drm_gem_object_evict(struct drm_gem_object *obj);
+int drm_gem_pin_unlocked(struct drm_gem_object *obj);
+void drm_gem_unpin_unlocked(struct drm_gem_object *obj);
+
#endif /* __DRM_GEM_H__ */
--
2.38.1
