1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef MIGRATE_MODE_H_INCLUDED
3 #define MIGRATE_MODE_H_INCLUDED
4 /*
5  * MIGRATE_ASYNC means never block
6  * MIGRATE_SYNC_LIGHT in the current implementation means to allow blocking
7  *	on most operations but not ->writepage as the potential stall time
8  *	is too significant
9  * MIGRATE_SYNC will block when migrating pages
10  * MIGRATE_SYNC_NO_COPY will block when migrating pages but will not copy pages
11  *	with the CPU. Instead, page copy happens outside the migratepage()
12  *	callback and is likely using a DMA engine. See migrate_vma() and HMM
13  *	(mm/hmm.c) for users of this mode.
14  */
15 enum migrate_mode {
16 	MIGRATE_ASYNC,
17 	MIGRATE_SYNC_LIGHT,
18 	MIGRATE_SYNC,
19 	MIGRATE_SYNC_NO_COPY,
20 };
21 
22 #endif		/* MIGRATE_MODE_H_INCLUDED */
23