|  | /* SPDX-License-Identifier: GPL-2.0 */ | 
|  | #ifndef MIGRATE_MODE_H_INCLUDED | 
|  | #define MIGRATE_MODE_H_INCLUDED | 
|  | /* | 
|  | * MIGRATE_ASYNC means never block | 
|  | * MIGRATE_SYNC_LIGHT in the current implementation means to allow blocking | 
|  | *	on most operations but not ->writepage as the potential stall time | 
|  | *	is too significant | 
|  | * MIGRATE_SYNC will block when migrating pages | 
|  | * MIGRATE_SYNC_NO_COPY will block when migrating pages but will not copy pages | 
|  | *	with the CPU. Instead, page copy happens outside the migratepage() | 
|  | *	callback and is likely using a DMA engine. See migrate_vma() and HMM | 
|  | *	(mm/hmm.c) for users of this mode. | 
|  | */ | 
|  | enum migrate_mode { | 
|  | MIGRATE_ASYNC, | 
|  | MIGRATE_SYNC_LIGHT, | 
|  | MIGRATE_SYNC, | 
|  | MIGRATE_SYNC_NO_COPY, | 
|  | }; | 
|  |  | 
|  | #endif		/* MIGRATE_MODE_H_INCLUDED */ |