1*4882a593Smuzhiyun /* 2*4882a593Smuzhiyun * Copyright (C) 2003 Sistina Software Limited. 3*4882a593Smuzhiyun * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. 4*4882a593Smuzhiyun * 5*4882a593Smuzhiyun * Device-Mapper dirty region hash interface. 6*4882a593Smuzhiyun * 7*4882a593Smuzhiyun * This file is released under the GPL. 8*4882a593Smuzhiyun */ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #ifndef DM_REGION_HASH_H 11*4882a593Smuzhiyun #define DM_REGION_HASH_H 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun #include <linux/dm-dirty-log.h> 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun /*----------------------------------------------------------------- 16*4882a593Smuzhiyun * Region hash 17*4882a593Smuzhiyun *----------------------------------------------------------------*/ 18*4882a593Smuzhiyun struct dm_region_hash; 19*4882a593Smuzhiyun struct dm_region; 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun /* 22*4882a593Smuzhiyun * States a region can have. 23*4882a593Smuzhiyun */ 24*4882a593Smuzhiyun enum dm_rh_region_states { 25*4882a593Smuzhiyun DM_RH_CLEAN = 0x01, /* No writes in flight. */ 26*4882a593Smuzhiyun DM_RH_DIRTY = 0x02, /* Writes in flight. */ 27*4882a593Smuzhiyun DM_RH_NOSYNC = 0x04, /* Out of sync. */ 28*4882a593Smuzhiyun DM_RH_RECOVERING = 0x08, /* Under resynchronization. */ 29*4882a593Smuzhiyun }; 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun /* 32*4882a593Smuzhiyun * Region hash create/destroy. 33*4882a593Smuzhiyun */ 34*4882a593Smuzhiyun struct bio_list; 35*4882a593Smuzhiyun struct dm_region_hash *dm_region_hash_create( 36*4882a593Smuzhiyun void *context, void (*dispatch_bios)(void *context, 37*4882a593Smuzhiyun struct bio_list *bios), 38*4882a593Smuzhiyun void (*wakeup_workers)(void *context), 39*4882a593Smuzhiyun void (*wakeup_all_recovery_waiters)(void *context), 40*4882a593Smuzhiyun sector_t target_begin, unsigned max_recovery, 41*4882a593Smuzhiyun struct dm_dirty_log *log, uint32_t region_size, 42*4882a593Smuzhiyun region_t nr_regions); 43*4882a593Smuzhiyun void dm_region_hash_destroy(struct dm_region_hash *rh); 44*4882a593Smuzhiyun 45*4882a593Smuzhiyun struct dm_dirty_log *dm_rh_dirty_log(struct dm_region_hash *rh); 46*4882a593Smuzhiyun 47*4882a593Smuzhiyun /* 48*4882a593Smuzhiyun * Conversion functions. 49*4882a593Smuzhiyun */ 50*4882a593Smuzhiyun region_t dm_rh_bio_to_region(struct dm_region_hash *rh, struct bio *bio); 51*4882a593Smuzhiyun sector_t dm_rh_region_to_sector(struct dm_region_hash *rh, region_t region); 52*4882a593Smuzhiyun void *dm_rh_region_context(struct dm_region *reg); 53*4882a593Smuzhiyun 54*4882a593Smuzhiyun /* 55*4882a593Smuzhiyun * Get region size and key (ie. number of the region). 56*4882a593Smuzhiyun */ 57*4882a593Smuzhiyun sector_t dm_rh_get_region_size(struct dm_region_hash *rh); 58*4882a593Smuzhiyun region_t dm_rh_get_region_key(struct dm_region *reg); 59*4882a593Smuzhiyun 60*4882a593Smuzhiyun /* 61*4882a593Smuzhiyun * Get/set/update region state (and dirty log). 62*4882a593Smuzhiyun * 63*4882a593Smuzhiyun */ 64*4882a593Smuzhiyun int dm_rh_get_state(struct dm_region_hash *rh, region_t region, int may_block); 65*4882a593Smuzhiyun void dm_rh_set_state(struct dm_region_hash *rh, region_t region, 66*4882a593Smuzhiyun enum dm_rh_region_states state, int may_block); 67*4882a593Smuzhiyun 68*4882a593Smuzhiyun /* Non-zero errors_handled leaves the state of the region NOSYNC */ 69*4882a593Smuzhiyun void dm_rh_update_states(struct dm_region_hash *rh, int errors_handled); 70*4882a593Smuzhiyun 71*4882a593Smuzhiyun /* Flush the region hash and dirty log. */ 72*4882a593Smuzhiyun int dm_rh_flush(struct dm_region_hash *rh); 73*4882a593Smuzhiyun 74*4882a593Smuzhiyun /* Inc/dec pending count on regions. */ 75*4882a593Smuzhiyun void dm_rh_inc_pending(struct dm_region_hash *rh, struct bio_list *bios); 76*4882a593Smuzhiyun void dm_rh_dec(struct dm_region_hash *rh, region_t region); 77*4882a593Smuzhiyun 78*4882a593Smuzhiyun /* Delay bios on regions. */ 79*4882a593Smuzhiyun void dm_rh_delay(struct dm_region_hash *rh, struct bio *bio); 80*4882a593Smuzhiyun 81*4882a593Smuzhiyun void dm_rh_mark_nosync(struct dm_region_hash *rh, struct bio *bio); 82*4882a593Smuzhiyun 83*4882a593Smuzhiyun /* 84*4882a593Smuzhiyun * Region recovery control. 85*4882a593Smuzhiyun */ 86*4882a593Smuzhiyun 87*4882a593Smuzhiyun /* Prepare some regions for recovery by starting to quiesce them. */ 88*4882a593Smuzhiyun void dm_rh_recovery_prepare(struct dm_region_hash *rh); 89*4882a593Smuzhiyun 90*4882a593Smuzhiyun /* Try fetching a quiesced region for recovery. */ 91*4882a593Smuzhiyun struct dm_region *dm_rh_recovery_start(struct dm_region_hash *rh); 92*4882a593Smuzhiyun 93*4882a593Smuzhiyun /* Report recovery end on a region. */ 94*4882a593Smuzhiyun void dm_rh_recovery_end(struct dm_region *reg, int error); 95*4882a593Smuzhiyun 96*4882a593Smuzhiyun /* Returns number of regions with recovery work outstanding. */ 97*4882a593Smuzhiyun int dm_rh_recovery_in_flight(struct dm_region_hash *rh); 98*4882a593Smuzhiyun 99*4882a593Smuzhiyun /* Start/stop recovery. */ 100*4882a593Smuzhiyun void dm_rh_start_recovery(struct dm_region_hash *rh); 101*4882a593Smuzhiyun void dm_rh_stop_recovery(struct dm_region_hash *rh); 102*4882a593Smuzhiyun 103*4882a593Smuzhiyun #endif /* DM_REGION_HASH_H */ 104