name : dm-region-hash.h /* SPDX-License-Identifier: GPL-2.0-only */ /* * 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 int 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 */