[PATCH v6 13/16] drm/msm: Allow lazy VM creation to fail

[Rob Clark <robin.clark@oss.qualcomm.com>]

In the next commit, we'll stop falling back to shared VM if private VM
creation fails.

This isn't expected to happen in practice, it would either require small
memory allocations to fail, or missing support in arm-smmu-qcom for
setting up per-process pgtable support (ie. missing patch during
bringup).

Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/adreno/adreno_gpu.c |  2 +-
 drivers/gpu/drm/msm/msm_drv.c           |  9 ++++++++-
 drivers/gpu/drm/msm/msm_gem_submit.c    | 12 ++++++++----
 drivers/gpu/drm/msm/msm_gem_vma.c       | 12 ++++++++----
 drivers/gpu/drm/msm/msm_submitqueue.c   |  8 +++++++-
 5 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 5738eac9aebd..84101e534ebe 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -359,7 +359,7 @@ int adreno_fault_handler(struct msm_gpu *gpu, unsigned long iova, int flags,
 static bool
 valid_per_process_vm(struct msm_gpu *gpu, struct drm_gpuvm *vm)
 {
-	return (vm != gpu->vm);
+	return vm && (vm != gpu->vm);
 }
 
 int adreno_get_param(struct msm_gpu *gpu, struct msm_context *ctx,
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 2fd1b717d8e6..52ff72d8e17a 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -422,10 +422,14 @@ static int msm_ioctl_gem_info_iova(struct drm_device *dev,
 {
 	struct msm_drm_private *priv = dev->dev_private;
 	struct msm_context *ctx = file->driver_priv;
+	struct drm_gpuvm *vm = msm_context_vm(dev, ctx);
 
 	if (!priv->gpu)
 		return -EINVAL;
 
+	if (!vm)
+		return UERR(ENOMEM, dev, "no VM");
+
 	if (msm_context_is_vmbind(ctx))
 		return UERR(EINVAL, dev, "VM_BIND is enabled");
 
@@ -436,7 +440,7 @@ static int msm_ioctl_gem_info_iova(struct drm_device *dev,
 	 * Don't pin the memory here - just get an address so that userspace can
 	 * be productive
 	 */
-	return msm_gem_get_iova(obj, msm_context_vm(dev, ctx), iova);
+	return msm_gem_get_iova(obj, vm, iova);
 }
 
 static int msm_ioctl_gem_info_set_iova(struct drm_device *dev,
@@ -450,6 +454,9 @@ static int msm_ioctl_gem_info_set_iova(struct drm_device *dev,
 	if (!priv->gpu)
 		return -EINVAL;
 
+	if (!vm)
+		return UERR(ENOMEM, dev, "no VM");
+
 	if (msm_context_is_vmbind(ctx))
 		return UERR(EINVAL, dev, "VM_BIND is enabled");
 
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 040354ee16d1..6b0bee6c39bc 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -30,7 +30,7 @@
  */
 
 static struct msm_gem_submit *submit_create(struct drm_device *dev,
-		struct msm_gpu *gpu,
+		struct msm_gpu *gpu, struct drm_gpuvm *vm,
 		struct msm_gpu_submitqueue *queue, uint32_t nr_bos,
 		uint32_t nr_cmds, u64 drm_client_id)
 {
@@ -66,7 +66,7 @@ static struct msm_gem_submit *submit_create(struct drm_device *dev,
 
 	kref_init(&submit->ref);
 	submit->dev = dev;
-	submit->vm = msm_context_vm(dev, queue->ctx);
+	submit->vm = vm;
 	submit->gpu = gpu;
 	submit->cmd = (void *)&submit->bos[nr_bos];
 	submit->queue = queue;
@@ -552,6 +552,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	struct msm_drm_private *priv = dev->dev_private;
 	struct drm_msm_gem_submit *args = data;
 	struct msm_context *ctx = file->driver_priv;
+	struct drm_gpuvm *vm = msm_context_vm(dev, ctx);
 	struct msm_gem_submit *submit = NULL;
 	struct msm_gpu *gpu = priv->gpu;
 	struct msm_gpu_submitqueue *queue;
@@ -567,10 +568,13 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 	if (!gpu)
 		return -ENXIO;
 
+	if (!vm)
+		return UERR(ENOMEM, dev, "no VM");
+
 	if (args->pad)
 		return -EINVAL;
 
-	if (to_msm_vm(ctx->vm)->unusable)
+	if (to_msm_vm(vm)->unusable)
 		return UERR(EPIPE, dev, "context is unusable");
 
 	/* for now, we just have 3d pipe.. eventually this would need to
@@ -607,7 +611,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
 		}
 	}
 
-	submit = submit_create(dev, gpu, queue, args->nr_bos, args->nr_cmds,
+	submit = submit_create(dev, gpu, vm, queue, args->nr_bos, args->nr_cmds,
 			       file->client_id);
 	if (IS_ERR(submit)) {
 		ret = PTR_ERR(submit);
diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c
index 3ed05ab0eeef..1fd4789f2be3 100644
--- a/drivers/gpu/drm/msm/msm_gem_vma.c
+++ b/drivers/gpu/drm/msm/msm_gem_vma.c
@@ -954,7 +954,7 @@ msm_gem_vm_close(struct drm_gpuvm *gpuvm)
 
 
 static struct msm_vm_bind_job *
-vm_bind_job_create(struct drm_device *dev, struct drm_file *file,
+vm_bind_job_create(struct drm_device *dev, struct drm_file *file, struct drm_gpuvm *vm,
 		   struct msm_gpu_submitqueue *queue, uint32_t nr_ops)
 {
 	struct msm_vm_bind_job *job;
@@ -971,7 +971,7 @@ vm_bind_job_create(struct drm_device *dev, struct drm_file *file,
 		return ERR_PTR(ret);
 	}
 
-	job->vm = msm_context_vm(dev, queue->ctx);
+	job->vm = vm;
 	job->queue = queue;
 	INIT_LIST_HEAD(&job->vm_ops);
 
@@ -1430,6 +1430,7 @@ msm_ioctl_vm_bind(struct drm_device *dev, void *data, struct drm_file *file)
 	struct msm_drm_private *priv = dev->dev_private;
 	struct drm_msm_vm_bind *args = data;
 	struct msm_context *ctx = file->driver_priv;
+	struct drm_gpuvm *vm = msm_context_vm(dev, ctx);
 	struct msm_vm_bind_job *job = NULL;
 	struct msm_gpu *gpu = priv->gpu;
 	struct msm_gpu_submitqueue *queue;
@@ -1444,11 +1445,14 @@ msm_ioctl_vm_bind(struct drm_device *dev, void *data, struct drm_file *file)
 	if (!gpu)
 		return -ENXIO;
 
+	if (!vm)
+		return UERR(ENOMEM, dev, "no VM");
+
 	/*
 	 * Maybe we could allow just UNMAP ops?  OTOH userspace should just
 	 * immediately close the device file and all will be torn down.
 	 */
-	if (to_msm_vm(msm_context_vm(dev, ctx))->unusable)
+	if (to_msm_vm(vm)->unusable)
 		return UERR(EPIPE, dev, "context is unusable");
 
 	/*
@@ -1479,7 +1483,7 @@ msm_ioctl_vm_bind(struct drm_device *dev, void *data, struct drm_file *file)
 		}
 	}
 
-	job = vm_bind_job_create(dev, file, queue, args->nr_ops);
+	job = vm_bind_job_create(dev, file, vm, queue, args->nr_ops);
 	if (IS_ERR(job)) {
 		ret = PTR_ERR(job);
 		goto out_post_unlock;
diff --git a/drivers/gpu/drm/msm/msm_submitqueue.c b/drivers/gpu/drm/msm/msm_submitqueue.c
index 233c4f35ab12..d307cdd17d90 100644
--- a/drivers/gpu/drm/msm/msm_submitqueue.c
+++ b/drivers/gpu/drm/msm/msm_submitqueue.c
@@ -174,6 +174,7 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_context *ctx,
 	struct msm_drm_private *priv = drm->dev_private;
 	struct msm_gpu_submitqueue *queue;
 	enum drm_sched_priority sched_prio;
+	struct drm_gpuvm *vm = NULL;
 	unsigned ring_nr;
 	int ret;
 
@@ -186,6 +187,11 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_context *ctx,
 	if (flags & MSM_SUBMITQUEUE_VM_BIND) {
 		unsigned sz;
 
+		vm = msm_context_vm(drm, ctx);
+
+		if (!vm)
+			return UERR(ENOMEM, drm, "no VM");
+
 		/* Not allowed for kernel managed VMs (ie. kernel allocs VA) */
 		if (!msm_context_is_vmbind(ctx))
 			return -EINVAL;
@@ -217,7 +223,7 @@ int msm_submitqueue_create(struct drm_device *drm, struct msm_context *ctx,
 	queue->flags = flags;
 
 	if (flags & MSM_SUBMITQUEUE_VM_BIND) {
-		struct drm_gpu_scheduler *sched = &to_msm_vm(msm_context_vm(drm, ctx))->sched;
+		struct drm_gpu_scheduler *sched = &to_msm_vm(vm)->sched;
 
 		queue->entity = &queue->_vm_bind_entity[0];
 
-- 
2.55.0