Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / include / linux / dm-region-hash.h
blob7e7c83de8324f757759ef7addc0cf7d4875c486f
1 /*
2 * Copyright (C) 2003 Sistina Software Limited.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 * Device-Mapper dirty region hash interface.
7 * This file is released under the GPL.
8 */
10 #ifndef DM_REGION_HASH_H
11 #define DM_REGION_HASH_H
13 #include <linux/dm-dirty-log.h>
15 /*-----------------------------------------------------------------
16 * Region hash
17 *----------------------------------------------------------------*/
18 struct dm_region_hash;
19 struct dm_region;
22 * States a region can have.
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. */
32 * Region hash create/destroy.
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);
45 struct dm_dirty_log *dm_rh_dirty_log(struct dm_region_hash *rh);
48 * Conversion functions.
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 region_t dm_rh_sector_to_region(struct dm_region_hash *rh, sector_t sector);
53 void *dm_rh_region_context(struct dm_region *reg);
56 * Get region size and key (ie. number of the region).
58 sector_t dm_rh_get_region_size(struct dm_region_hash *rh);
59 region_t dm_rh_get_region_key(struct dm_region *reg);
62 * Get/set/update region state (and dirty log).
65 int dm_rh_get_state(struct dm_region_hash *rh, region_t region, int may_block);
66 void dm_rh_set_state(struct dm_region_hash *rh, region_t region,
67 enum dm_rh_region_states state, int may_block);
69 /* Non-zero errors_handled leaves the state of the region NOSYNC */
70 void dm_rh_update_states(struct dm_region_hash *rh, int errors_handled);
72 /* Flush the region hash and dirty log. */
73 int dm_rh_flush(struct dm_region_hash *rh);
75 /* Inc/dec pending count on regions. */
76 void dm_rh_inc(struct dm_region_hash *rh, region_t region);
77 void dm_rh_inc_pending(struct dm_region_hash *rh, struct bio_list *bios);
78 void dm_rh_dec(struct dm_region_hash *rh, region_t region);
80 /* Delay bios on regions. */
81 void dm_rh_delay(struct dm_region_hash *rh, struct bio *bio);
82 void dm_rh_delay_by_region(struct dm_region_hash *rh, struct bio *bio,
83 region_t region);
85 void dm_rh_mark_nosync(struct dm_region_hash *rh, struct bio *bio);
88 * Region recovery control.
91 /* Prepare some regions for recovery by starting to quiesce them. */
92 void dm_rh_recovery_prepare(struct dm_region_hash *rh);
94 /* Try fetching a quiesced region for recovery. */
95 struct dm_region *dm_rh_recovery_start(struct dm_region_hash *rh);
97 /* Report recovery end on a region. */
98 void dm_rh_recovery_end(struct dm_region *reg, int error);
100 /* Returns number of regions with recovery work outstanding. */
101 int dm_rh_recovery_in_flight(struct dm_region_hash *rh);
103 /* Start/stop recovery. */
104 void dm_rh_start_recovery(struct dm_region_hash *rh);
105 void dm_rh_stop_recovery(struct dm_region_hash *rh);
107 #endif /* DM_REGION_HASH_H */