diff options
Diffstat (limited to 'kernel/include/linux/dm-region-hash.h')
| -rw-r--r-- | kernel/include/linux/dm-region-hash.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/kernel/include/linux/dm-region-hash.h b/kernel/include/linux/dm-region-hash.h new file mode 100644 index 000000000..9e2a7a401 --- /dev/null +++ b/kernel/include/linux/dm-region-hash.h @@ -0,0 +1,103 @@ +/* + * Copyright (C) 2003 Sistina Software Limited. + * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. + * + * Device-Mapper dirty region hash interface. + * + * This file is released under the GPL. + */ + +#ifndef DM_REGION_HASH_H +#define DM_REGION_HASH_H + +#include <linux/dm-dirty-log.h> + +/*----------------------------------------------------------------- + * Region hash + *----------------------------------------------------------------*/ +struct dm_region_hash; +struct dm_region; + +/* + * States a region can have. + */ +enum dm_rh_region_states { + DM_RH_CLEAN = 0x01, /* No writes in flight. */ + DM_RH_DIRTY = 0x02, /* Writes in flight. */ + DM_RH_NOSYNC = 0x04, /* Out of sync. */ + DM_RH_RECOVERING = 0x08, /* Under resynchronization. */ +}; + +/* + * Region hash create/destroy. + */ +struct bio_list; +struct dm_region_hash *dm_region_hash_create( + void *context, void (*dispatch_bios)(void *context, + struct bio_list *bios), + void (*wakeup_workers)(void *context), + void (*wakeup_all_recovery_waiters)(void *context), + sector_t target_begin, unsigned max_recovery, + struct dm_dirty_log *log, uint32_t region_size, + region_t nr_regions); +void dm_region_hash_destroy(struct dm_region_hash *rh); + +struct dm_dirty_log *dm_rh_dirty_log(struct dm_region_hash *rh); + +/* + * Conversion functions. + */ +region_t dm_rh_bio_to_region(struct dm_region_hash *rh, struct bio *bio); +sector_t dm_rh_region_to_sector(struct dm_region_hash *rh, region_t region); +void *dm_rh_region_context(struct dm_region *reg); + +/* + * Get region size and key (ie. number of the region). + */ +sector_t dm_rh_get_region_size(struct dm_region_hash *rh); +region_t dm_rh_get_region_key(struct dm_region *reg); + +/* + * Get/set/update region state (and dirty log). + * + */ +int dm_rh_get_state(struct dm_region_hash *rh, region_t region, int may_block); +void dm_rh_set_state(struct dm_region_hash *rh, region_t region, + enum dm_rh_region_states state, int may_block); + +/* Non-zero errors_handled leaves the state of the region NOSYNC */ +void dm_rh_update_states(struct dm_region_hash *rh, int errors_handled); + +/* Flush the region hash and dirty log. */ +int dm_rh_flush(struct dm_region_hash *rh); + +/* Inc/dec pending count on regions. */ +void dm_rh_inc_pending(struct dm_region_hash *rh, struct bio_list *bios); +void dm_rh_dec(struct dm_region_hash *rh, region_t region); + +/* Delay bios on regions. */ +void dm_rh_delay(struct dm_region_hash *rh, struct bio *bio); + +void dm_rh_mark_nosync(struct dm_region_hash *rh, struct bio *bio); + +/* + * Region recovery control. + */ + +/* Prepare some regions for recovery by starting to quiesce them. */ +void dm_rh_recovery_prepare(struct dm_region_hash *rh); + +/* Try fetching a quiesced region for recovery. */ +struct dm_region *dm_rh_recovery_start(struct dm_region_hash *rh); + +/* Report recovery end on a region. */ +void dm_rh_recovery_end(struct dm_region *reg, int error); + +/* Returns number of regions with recovery work outstanding. */ +int dm_rh_recovery_in_flight(struct dm_region_hash *rh); + +/* Start/stop recovery. */ +void dm_rh_start_recovery(struct dm_region_hash *rh); +void dm_rh_stop_recovery(struct dm_region_hash *rh); + +#endif /* DM_REGION_HASH_H */ |