| Andrew Morton | 6536e31 | 2012-01-20 14:33:53 -0800 | [diff] [blame] | 1 | #ifndef MIGRATE_MODE_H_INCLUDED |
| 2 | #define MIGRATE_MODE_H_INCLUDED |
| 3 | /* |
| 4 | * MIGRATE_ASYNC means never block |
| 5 | * MIGRATE_SYNC_LIGHT in the current implementation means to allow blocking |
| 6 | * on most operations but not ->writepage as the potential stall time |
| 7 | * is too significant |
| 8 | * MIGRATE_SYNC will block when migrating pages |
| Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame^] | 9 | * MIGRATE_SYNC_NO_COPY will block when migrating pages but will not copy pages |
| 10 | * with the CPU. Instead, page copy happens outside the migratepage() |
| 11 | * callback and is likely using a DMA engine. See migrate_vma() and HMM |
| 12 | * (mm/hmm.c) for users of this mode. |
| Andrew Morton | 6536e31 | 2012-01-20 14:33:53 -0800 | [diff] [blame] | 13 | */ |
| 14 | enum migrate_mode { |
| 15 | MIGRATE_ASYNC, |
| 16 | MIGRATE_SYNC_LIGHT, |
| 17 | MIGRATE_SYNC, |
| Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame^] | 18 | MIGRATE_SYNC_NO_COPY, |
| Andrew Morton | 6536e31 | 2012-01-20 14:33:53 -0800 | [diff] [blame] | 19 | }; |
| 20 | |
| 21 | #endif /* MIGRATE_MODE_H_INCLUDED */ |