drm/amdkfd: Fix CRIU restore op due to doorbell offset

Recently introduced change to allocate doorbells only when the first
queue is created or mapped for CPU / GPU access, did not consider
Checkpoint Restore scenario completely. This fix allows the CRIU restore
operation by extending the doorbell optimization to CRIU restore
scenario.

Fixes: 16f00131 ("drm/amdkfd: Allocate doorbells only when needed")
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_chardev.c

@@ -2153,6 +2153,12 @@ static int criu_restore_devices(struct kfd_process *p,
 			ret = PTR_ERR(pdd);
 			goto exit;
 		}
+
+		if (!pdd->doorbell_index &&
+		    kfd_alloc_process_doorbells(pdd->dev, &pdd->doorbell_index) < 0) {
+			ret = -ENOMEM;
+			goto exit;
+		}
 	}
 
 	/*

drivers/gpu/drm/amd/amdkfd/kfd_doorbell.c

@@ -303,6 +303,9 @@ int kfd_alloc_process_doorbells(struct kfd_dev *kfd, unsigned int *doorbell_inde
 	if (r > 0)
 		*doorbell_index = r;
 
+	if (r < 0)
+		pr_err("Failed to allocate process doorbells\n");
+
 	return r;
 }
 

drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c

@@ -857,6 +857,13 @@ int kfd_criu_restore_queue(struct kfd_process *p,
 		ret = -EINVAL;
 		goto exit;
 	}
+
+	if (!pdd->doorbell_index &&
+	    kfd_alloc_process_doorbells(pdd->dev, &pdd->doorbell_index) < 0) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
 	/* data stored in this order: mqd, ctl_stack */
 	mqd = q_extra_data;
 	ctl_stack = mqd + q_data->mqd_size;