drm/nouveau/disp: use private spinlock to control exclusive access to disp

nvkm_subdev.mutex is going away.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/engine/disp.h b/drivers/gpu/drm/nouveau/include/nvkm/engine/disp.h
index 0f6fa66..17288ea 100644 (file)
--- a/drivers/gpu/drm/nouveau/include/nvkm/engine/disp.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/engine/disp.h
@@ -17,7 +17,10 @@ struct nvkm_disp {
        struct nvkm_event hpd;
        struct nvkm_event vblank;
 
-       struct nvkm_oproxy *client;
+       struct {
+               spinlock_t lock;
+               struct nvkm_oproxy *object;
+       } client;
 };
 
 int nv04_disp_new(struct nvkm_device *, int, struct nvkm_disp **);

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/base.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/base.c
index cbd33e8..8540e28 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/base.c
@@ -149,10 +149,10 @@ static void
 nvkm_disp_class_del(struct nvkm_oproxy *oproxy)
 {
        struct nvkm_disp *disp = nvkm_disp(oproxy->base.engine);
-       mutex_lock(&disp->engine.subdev.mutex);
-       if (disp->client == oproxy)
-               disp->client = NULL;
-       mutex_unlock(&disp->engine.subdev.mutex);
+       spin_lock(&disp->client.lock);
+       if (disp->client.object == oproxy)
+               disp->client.object = NULL;
+       spin_unlock(&disp->client.lock);
 }
 
 static const struct nvkm_oproxy_func
@@ -175,13 +175,13 @@ nvkm_disp_class_new(struct nvkm_device *device,
                return ret;
        *pobject = &oproxy->base;
 
-       mutex_lock(&disp->engine.subdev.mutex);
-       if (disp->client) {
-               mutex_unlock(&disp->engine.subdev.mutex);
+       spin_lock(&disp->client.lock);
+       if (disp->client.object) {
+               spin_unlock(&disp->client.lock);
                return -EBUSY;
        }
-       disp->client = oproxy;
-       mutex_unlock(&disp->engine.subdev.mutex);
+       disp->client.object = oproxy;
+       spin_unlock(&disp->client.lock);
 
        return sclass->ctor(disp, oclass, data, size, &oproxy->object);
 }
@@ -480,6 +480,7 @@ nvkm_disp_ctor(const struct nvkm_disp_func *func, struct nvkm_device *device,
        INIT_LIST_HEAD(&disp->ior);
        INIT_LIST_HEAD(&disp->outp);
        INIT_LIST_HEAD(&disp->conn);
+       spin_lock_init(&disp->client.lock);
        return nvkm_engine_ctor(&nvkm_disp, device, index, true, &disp->engine);
 }