drm/amdgpu: unmap and remove csa_va properly

Root PD BO should be reserved before unmap and remove
a bo_va from VM otherwise lockdep will complain.

v2: check fpriv->csa_va is not NULL instead of amdgpu_mcbp (christian)

[14616.936827] WARNING: CPU: 6 PID: 1711 at drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1762 amdgpu_vm_bo_del+0x399/0x3f0 [amdgpu]
[14616.937096] Call Trace:
[14616.937097] <TASK>
[14616.937102] amdgpu_driver_postclose_kms+0x249/0x2f0 [amdgpu]
[14616.937187] drm_file_free+0x1d6/0x300 [drm]
[14616.937207] drm_close_helper.isra.0+0x62/0x70 [drm]
[14616.937220] drm_release+0x5e/0x100 [drm]
[14616.937234] __fput+0x9f/0x280
[14616.937239] ____fput+0xe/0x20
[14616.937241] task_work_run+0x61/0x90
[14616.937246] exit_to_user_mode_prepare+0x215/0x220
[14616.937251] syscall_exit_to_user_mode+0x2a/0x60
[14616.937254] do_syscall_64+0x48/0x90
[14616.937257] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Signed-off-by: Lang Yu <[e-mail]>
Acked-by: Christian König <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c

···
 	ttm_eu_backoff_reservation(&ticket, &list);
 	return 0;
 }
+
+int amdgpu_unmap_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm,
+			    struct amdgpu_bo *bo, struct amdgpu_bo_va *bo_va,
+			    uint64_t csa_addr)
+{
+	struct ww_acquire_ctx ticket;
+	struct list_head list;
+	struct amdgpu_bo_list_entry pd;
+	struct ttm_validate_buffer csa_tv;
+	int r;
+
+	INIT_LIST_HEAD(&list);
+	INIT_LIST_HEAD(&csa_tv.head);
+	csa_tv.bo = &bo->tbo;
+	csa_tv.num_shared = 1;
+
+	list_add(&csa_tv.head, &list);
+	amdgpu_vm_get_pd_bo(vm, &list, &pd);
+
+	r = ttm_eu_reserve_buffers(&ticket, &list, true, NULL);
+	if (r) {
+		DRM_ERROR("failed to reserve CSA,PD BOs: err=%d\n", r);
+		return r;
+	}
+
+	r = amdgpu_vm_bo_unmap(adev, bo_va, csa_addr);
+	if (r) {
+		DRM_ERROR("failed to do bo_unmap on static CSA, err=%d\n", r);
+		ttm_eu_backoff_reservation(&ticket, &list);
+		return r;
+	}
+
+	amdgpu_vm_bo_del(adev, bo_va);
+
+	ttm_eu_backoff_reservation(&ticket, &list);
+
+	return 0;
+}

drivers/gpu/drm/amd/amdgpu/amdgpu_csa.h

···
 int amdgpu_map_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 			  struct amdgpu_bo *bo, struct amdgpu_bo_va **bo_va,
 			  uint64_t csa_addr, uint32_t size);
+int amdgpu_unmap_static_csa(struct amdgpu_device *adev, struct amdgpu_vm *vm,
+			    struct amdgpu_bo *bo, struct amdgpu_bo_va *bo_va,
+			    uint64_t csa_addr);
 void amdgpu_free_static_csa(struct amdgpu_bo **bo);
 
 #endif

drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c

···
 	if (amdgpu_device_ip_get_ip_block(adev, AMD_IP_BLOCK_TYPE_VCE) != NULL)
 		amdgpu_vce_free_handles(adev, file_priv);
 
-	if (amdgpu_mcbp) {
-		/* TODO: how to handle reserve failure */
-		BUG_ON(amdgpu_bo_reserve(adev->virt.csa_obj, true));
-		amdgpu_vm_bo_del(adev, fpriv->csa_va);
+	if (fpriv->csa_va) {
+		uint64_t csa_addr = amdgpu_csa_vaddr(adev) & AMDGPU_GMC_HOLE_MASK;
+
+		WARN_ON(amdgpu_unmap_static_csa(adev, &fpriv->vm, adev->virt.csa_obj,
+						fpriv->csa_va, csa_addr));
 		fpriv->csa_va = NULL;
-		amdgpu_bo_unreserve(adev->virt.csa_obj);
 	}
 
 	pasid = fpriv->vm.pasid;