accel/ivpu: Fix dev open/close races with unbind

  - Add context_list_lock to synchronize user context addition/removal
  - Use drm_dev_enter() to prevent unbinding the device during ivpu_open()
    and vpu address allocation

Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Wachowski, Karol <karol.wachowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240122120945.1150728-2-jacek.lawrynowicz@linux.intel.com

1 files changed, 8 insertions, 10 deletions

diff --git a/drivers/accel/ivpu/ivpu_gem.c b/drivers/accel/ivpu/ivpu_gem.c
index 16f3035b91c0..e9ddbe9f50eb 100644
--- a/drivers/accel/ivpu/ivpu_gem.c
+++ b/drivers/accel/ivpu/ivpu_gem.c
@@ -77,7 +77,10 @@ ivpu_bo_alloc_vpu_addr(struct ivpu_bo *bo, struct ivpu_mmu_context *ctx,
 		       const struct ivpu_addr_range *range)
 {
 	struct ivpu_device *vdev = ivpu_bo_to_vdev(bo);
-	int ret;
+	int idx, ret;
+
+	if (!drm_dev_enter(&vdev->drm, &idx))
+		return -ENODEV;
 
 	mutex_lock(&bo->lock);
 
@@ -93,6 +96,8 @@ ivpu_bo_alloc_vpu_addr(struct ivpu_bo *bo, struct ivpu_mmu_context *ctx,
 
 	mutex_unlock(&bo->lock);
 
+	drm_dev_exit(idx);
+
 	return ret;
 }
 
@@ -128,14 +133,7 @@ static void ivpu_bo_unbind_locked(struct ivpu_bo *bo)
 	dma_resv_unlock(bo->base.base.resv);
 }
 
-static void ivpu_bo_unbind(struct ivpu_bo *bo)
-{
-	mutex_lock(&bo->lock);
-	ivpu_bo_unbind_locked(bo);
-	mutex_unlock(&bo->lock);
-}
-
-void ivpu_bo_remove_all_bos_from_context(struct ivpu_device *vdev, struct ivpu_mmu_context *ctx)
+void ivpu_bo_unbind_all_bos_from_context(struct ivpu_device *vdev, struct ivpu_mmu_context *ctx)
 {
 	struct ivpu_bo *bo;
 
@@ -239,7 +237,7 @@ static void ivpu_bo_free(struct drm_gem_object *obj)
 
 	drm_WARN_ON(&vdev->drm, !dma_resv_test_signaled(obj->resv, DMA_RESV_USAGE_READ));
 
-	ivpu_bo_unbind(bo);
+	ivpu_bo_unbind_locked(bo);
 	mutex_destroy(&bo->lock);
 
 	drm_WARN_ON(obj->dev, bo->base.pages_use_count > 1);