| Heinz Mauelshagen | 1f965b1 | 2008-10-21 17:45:06 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2003 Sistina Software Limited. |
| 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
| 4 | * |
| 5 | * Device-Mapper dirty region hash interface. |
| 6 | * |
| 7 | * This file is released under the GPL. |
| 8 | */ |
| 9 | |
| 10 | #ifndef DM_REGION_HASH_H |
| 11 | #define DM_REGION_HASH_H |
| 12 | |
| 13 | #include <linux/dm-dirty-log.h> |
| 14 | |
| 15 | /*----------------------------------------------------------------- |
| 16 | * Region hash |
| 17 | *----------------------------------------------------------------*/ |
| 18 | struct dm_region_hash; |
| 19 | struct dm_region; |
| 20 | |
| 21 | /* |
| 22 | * States a region can have. |
| 23 | */ |
| 24 | enum dm_rh_region_states { |
| 25 | DM_RH_CLEAN = 0x01, /* No writes in flight. */ |
| 26 | DM_RH_DIRTY = 0x02, /* Writes in flight. */ |
| 27 | DM_RH_NOSYNC = 0x04, /* Out of sync. */ |
| 28 | DM_RH_RECOVERING = 0x08, /* Under resynchronization. */ |
| 29 | }; |
| 30 | |
| 31 | /* |
| 32 | * Region hash create/destroy. |
| 33 | */ |
| 34 | struct bio_list; |
| 35 | struct dm_region_hash *dm_region_hash_create( |
| 36 | void *context, void (*dispatch_bios)(void *context, |
| 37 | struct bio_list *bios), |
| 38 | void (*wakeup_workers)(void *context), |
| 39 | void (*wakeup_all_recovery_waiters)(void *context), |
| 40 | sector_t target_begin, unsigned max_recovery, |
| 41 | struct dm_dirty_log *log, uint32_t region_size, |
| 42 | region_t nr_regions); |
| 43 | void dm_region_hash_destroy(struct dm_region_hash *rh); |
| 44 | |
| 45 | struct dm_dirty_log *dm_rh_dirty_log(struct dm_region_hash *rh); |
| 46 | |
| 47 | /* |
| 48 | * Conversion functions. |
| 49 | */ |
| 50 | region_t dm_rh_bio_to_region(struct dm_region_hash *rh, struct bio *bio); |
| 51 | sector_t dm_rh_region_to_sector(struct dm_region_hash *rh, region_t region); |
| 52 | void *dm_rh_region_context(struct dm_region *reg); |
| 53 | |
| 54 | /* |
| 55 | * Get region size and key (ie. number of the region). |
| 56 | */ |
| 57 | sector_t dm_rh_get_region_size(struct dm_region_hash *rh); |
| 58 | region_t dm_rh_get_region_key(struct dm_region *reg); |
| 59 | |
| 60 | /* |
| 61 | * Get/set/update region state (and dirty log). |
| 62 | * |
| 63 | */ |
| 64 | int dm_rh_get_state(struct dm_region_hash *rh, region_t region, int may_block); |
| 65 | void dm_rh_set_state(struct dm_region_hash *rh, region_t region, |
| 66 | enum dm_rh_region_states state, int may_block); |
| 67 | |
| 68 | /* Non-zero errors_handled leaves the state of the region NOSYNC */ |
| 69 | void dm_rh_update_states(struct dm_region_hash *rh, int errors_handled); |
| 70 | |
| 71 | /* Flush the region hash and dirty log. */ |
| 72 | int dm_rh_flush(struct dm_region_hash *rh); |
| 73 | |
| 74 | /* Inc/dec pending count on regions. */ |
| 75 | void dm_rh_inc_pending(struct dm_region_hash *rh, struct bio_list *bios); |
| 76 | void dm_rh_dec(struct dm_region_hash *rh, region_t region); |
| 77 | |
| 78 | /* Delay bios on regions. */ |
| 79 | void dm_rh_delay(struct dm_region_hash *rh, struct bio *bio); |
| 80 | |
| 81 | void dm_rh_mark_nosync(struct dm_region_hash *rh, |
| 82 | struct bio *bio, unsigned done, int error); |
| 83 | |
| 84 | /* |
| 85 | * Region recovery control. |
| 86 | */ |
| 87 | |
| 88 | /* Prepare some regions for recovery by starting to quiesce them. */ |
| 89 | void dm_rh_recovery_prepare(struct dm_region_hash *rh); |
| 90 | |
| 91 | /* Try fetching a quiesced region for recovery. */ |
| 92 | struct dm_region *dm_rh_recovery_start(struct dm_region_hash *rh); |
| 93 | |
| 94 | /* Report recovery end on a region. */ |
| 95 | void dm_rh_recovery_end(struct dm_region *reg, int error); |
| 96 | |
| 97 | /* Returns number of regions with recovery work outstanding. */ |
| 98 | int dm_rh_recovery_in_flight(struct dm_region_hash *rh); |
| 99 | |
| 100 | /* Start/stop recovery. */ |
| 101 | void dm_rh_start_recovery(struct dm_region_hash *rh); |
| 102 | void dm_rh_stop_recovery(struct dm_region_hash *rh); |
| 103 | |
| 104 | #endif /* DM_REGION_HASH_H */ |