drm/msm: Add a context pointer to the submitqueue

Each submitqueue is attached to a context. Add a pointer to the
context to the submitqueue at create time and refcount it so
that it stays around through the life of the queue.

Co-developed-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/gpu/drm/msm/msm_drv.c

@@ -586,6 +586,7 @@ static int context_init(struct drm_device *dev, struct drm_file *file)
 	if (!ctx)
 		return -ENOMEM;
 
+	kref_init(&ctx->ref);
 	msm_submitqueue_init(dev, ctx);
 
 	ctx->aspace = priv->gpu ? priv->gpu->aspace : NULL;
@@ -607,7 +608,7 @@ static int msm_open(struct drm_device *dev, struct drm_file *file)
 static void context_close(struct msm_file_private *ctx)
 {
 	msm_submitqueue_close(ctx);
-	kfree(ctx);
+	msm_file_private_put(ctx);
 }
 
 static void msm_postclose(struct drm_device *dev, struct drm_file *file)

drivers/gpu/drm/msm/msm_drv.h

@@ -57,6 +57,7 @@ struct msm_file_private {
 	struct list_head submitqueues;
 	int queueid;
 	struct msm_gem_address_space *aspace;
+	struct kref ref;
 };
 
 enum msm_mdp_plane_property {
@@ -428,6 +429,25 @@ void msm_submitqueue_close(struct msm_file_private *ctx);
 
 void msm_submitqueue_destroy(struct kref *kref);
 
+static inline void __msm_file_private_destroy(struct kref *kref)
+{
+	struct msm_file_private *ctx = container_of(kref,
+		struct msm_file_private, ref);
+
+	kfree(ctx);
+}
+
+static inline void msm_file_private_put(struct msm_file_private *ctx)
+{
+	kref_put(&ctx->ref, __msm_file_private_destroy);
+}
+
+static inline struct msm_file_private *msm_file_private_get(
+	struct msm_file_private *ctx)
+{
+	kref_get(&ctx->ref);
+	return ctx;
+}
 
 #define DBG(fmt, ...) DRM_DEBUG_DRIVER(fmt"\n", ##__VA_ARGS__)
 #define VERB(fmt, ...) if (0) DRM_DEBUG_DRIVER(fmt"\n", ##__VA_ARGS__)

drivers/gpu/drm/msm/msm_gem.h

@@ -142,6 +142,7 @@ struct msm_gem_submit {
 	bool valid;         /* true if no cmdstream patching needed */
 	bool in_rb;         /* "sudo" mode, copy cmds into RB */
 	struct msm_ringbuffer *ring;
+	struct msm_file_private *ctx;
 	unsigned int nr_cmds;
 	unsigned int nr_bos;
 	u32 ident;	   /* A "identifier" for the submit for logging */

drivers/gpu/drm/msm/msm_gem_submit.c

@@ -27,7 +27,7 @@
 #define BO_PINNED   0x2000
 
 static struct msm_gem_submit *submit_create(struct drm_device *dev,
-		struct msm_gpu *gpu, struct msm_gem_address_space *aspace,
+		struct msm_gpu *gpu,
 		struct msm_gpu_submitqueue *queue, uint32_t nr_bos,
 		uint32_t nr_cmds)
 {
@@ -43,7 +43,7 @@ static struct msm_gem_submit *submit_create(struct drm_device *dev,
 		return NULL;
 
 	submit->dev = dev;
-	submit->aspace = aspace;
+	submit->aspace = queue->ctx->aspace;
 	submit->gpu = gpu;
 	submit->fence = NULL;
 	submit->cmd = (void *)&submit->bos[nr_bos];
@@ -677,7 +677,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 		}
 	}
 
-	submit = submit_create(dev, gpu, ctx->aspace, queue, args->nr_bos,
+	submit = submit_create(dev, gpu, queue, args->nr_bos,
 		args->nr_cmds);
 	if (!submit) {
 		ret = -ENOMEM;

drivers/gpu/drm/msm/msm_gpu.h

@@ -193,6 +193,7 @@ struct msm_gpu_submitqueue {
 	u32 flags;
 	u32 prio;
 	int faults;
+	struct msm_file_private *ctx;
 	struct list_head node;
 	struct kref ref;
 };

drivers/gpu/drm/msm/msm_submitqueue.c

@@ -12,6 +12,8 @@ void msm_submitqueue_destroy(struct kref *kref)
 	struct msm_gpu_submitqueue *queue = container_of(kref,
 		struct msm_gpu_submitqueue, ref);
 
+	msm_file_private_put(queue->ctx);
+
 	kfree(queue);
 }
 
@@ -83,6 +85,7 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
 
 	write_lock(&ctx->queuelock);
 
+	queue->ctx = msm_file_private_get(ctx);
 	queue->id = ctx->queueid++;
 
 	if (id)