14 #include <linux/dm-dirty-log.h>
18 #define DM_MSG_PREFIX "dirty region log"
56  * Log modules are named "dm-log-" followed by the 'type_name'.
58  * This function will first try the module "dm-log-<type_name>",
62  * 'dm-log-clustered-disk' then 'dm-log-clustered'.
80 		DMWARN("No memory left to attempt log module load for \"%s\"",  in get_type()
85 	while (request_module("dm-log-%s", type_name_dup) ||  in get_type()
154 	struct dm_dirty_log *log;  in dm_dirty_log_create()  local
156 	log = kmalloc(sizeof(*log), GFP_KERNEL);  in dm_dirty_log_create()
157 	if (!log)  in dm_dirty_log_create()
162 		kfree(log);  in dm_dirty_log_create()
166 	log->flush_callback_fn = flush_callback_fn;  in dm_dirty_log_create()
167 	log->type = type;  in dm_dirty_log_create()
168 	if (type->ctr(log, ti, argc, argv)) {  in dm_dirty_log_create()
169 		kfree(log);  in dm_dirty_log_create()
174 	return log;  in dm_dirty_log_create()
178 void dm_dirty_log_destroy(struct dm_dirty_log *log)  in dm_dirty_log_destroy()  argument
180 	log->type->dtr(log);  in dm_dirty_log_destroy()
181 	put_type(log->type);  in dm_dirty_log_destroy()
182 	kfree(log);  in dm_dirty_log_destroy()
246 	 * Disk log fields
319 static int read_header(struct log_c *log)  in read_header()  argument
323 	r = rw_header(log, REQ_OP_READ);  in read_header()
327 	header_from_disk(&log->header, log->disk_header);  in read_header()
329 	/* New log required? */  in read_header()
330 	if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {  in read_header()
331 		log->header.magic = MIRROR_MAGIC;  in read_header()
332 		log->header.version = MIRROR_DISK_VERSION;  in read_header()
333 		log->header.nr_regions = 0;  in read_header()
337 	if (log->header.version == 1)  in read_header()
338 		log->header.version = 2;  in read_header()
341 	if (log->header.version != MIRROR_DISK_VERSION) {  in read_header()
342 		DMWARN("incompatible disk log version");  in read_header()
362  * core log constructor/destructor
368 static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,  in create_log_context()  argument
382 		DMWARN("wrong number of arguments to dirty region log");  in create_log_context()
392 			DMWARN("unrecognised sync argument to dirty region log: %s", argv[1]);  in create_log_context()
407 		DMWARN("couldn't allocate core log");  in create_log_context()
428 	 * Disk log?  in create_log_context()
453 			DMWARN("log device %s too small: need %llu bytes",  in create_log_context()
473 			DMWARN("couldn't allocate disk log buffer");  in create_log_context()
513 	log->context = lc;  in create_log_context()
518 static int core_ctr(struct dm_dirty_log *log, struct dm_target *ti,  in core_ctr()  argument
521 	return create_log_context(log, ti, argc, argv, NULL);  in core_ctr()
531 static void core_dtr(struct dm_dirty_log *log)  in core_dtr()  argument
533 	struct log_c *lc = log->context;  in core_dtr()
541  * disk log constructor/destructor
546 static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,  in disk_ctr()  argument
553 		DMWARN("wrong number of arguments to disk dirty region log");  in disk_ctr()
561 	r = create_log_context(log, ti, argc - 1, argv + 1, dev);  in disk_ctr()
570 static void disk_dtr(struct dm_dirty_log *log)  in disk_dtr()  argument
572 	struct log_c *lc = log->context;  in disk_dtr()
589 static int disk_resume(struct dm_dirty_log *log)  in disk_resume()  argument
593 	struct log_c *lc = log->context;  in disk_resume()
599 		DMWARN("%s: Failed to read header on dirty region log device",  in disk_resume()
603 		 * If the log device cannot be read, we must assume  in disk_resume()
645 		DMWARN("%s: Failed to write header on dirty region log device",  in disk_resume()
653 static uint32_t core_get_region_size(struct dm_dirty_log *log)  in core_get_region_size()  argument
655 	struct log_c *lc = log->context;  in core_get_region_size()
660 static int core_resume(struct dm_dirty_log *log)  in core_resume()  argument
662 	struct log_c *lc = log->context;  in core_resume()
668 static int core_is_clean(struct dm_dirty_log *log, region_t region)  in core_is_clean()  argument
670 	struct log_c *lc = log->context;  in core_is_clean()
675 static int core_in_sync(struct dm_dirty_log *log, region_t region, int block)  in core_in_sync()  argument
677 	struct log_c *lc = log->context;  in core_in_sync()
682 static int core_flush(struct dm_dirty_log *log)  in core_flush()  argument
688 static int disk_flush(struct dm_dirty_log *log)  in disk_flush()  argument
691 	struct log_c *lc = log->context;  in disk_flush()
693 	/* only write if the log has changed */  in disk_flush()
697 	if (lc->touched_cleaned && log->flush_callback_fn &&  in disk_flush()
698 	    log->flush_callback_fn(lc->ti)) {  in disk_flush()
702 		 * re-reading the log off disk). So mark all of them  in disk_flush()
728 static void core_mark_region(struct dm_dirty_log *log, region_t region)  in core_mark_region()  argument
730 	struct log_c *lc = log->context;  in core_mark_region()
735 static void core_clear_region(struct dm_dirty_log *log, region_t region)  in core_clear_region()  argument
737 	struct log_c *lc = log->context;  in core_clear_region()
743 static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)  in core_get_resync_work()  argument
745 	struct log_c *lc = log->context;  in core_get_resync_work()
765 static void core_set_region_sync(struct dm_dirty_log *log, region_t region,  in core_set_region_sync()  argument
768 	struct log_c *lc = log->context;  in core_set_region_sync()
780 static region_t core_get_sync_count(struct dm_dirty_log *log)  in core_get_sync_count()  argument
782 	struct log_c *lc = log->context;  in core_get_sync_count()
793 static int core_status(struct dm_dirty_log *log, status_type_t status,  in core_status()  argument
797 	struct log_c *lc = log->context;  in core_status()
801 		DMEMIT("1 %s", log->type->name);  in core_status()
805 		DMEMIT("%s %u %u ", log->type->name,  in core_status()
818 static int disk_status(struct dm_dirty_log *log, status_type_t status,  in disk_status()  argument
822 	struct log_c *lc = log->context;  in disk_status()
826 		DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,  in disk_status()
833 		DMEMIT("%s %u %s %u ", log->type->name,  in disk_status()
890 		DMWARN("couldn't register core log");  in dm_dirty_log_init()
910 MODULE_DESCRIPTION(DM_NAME " dirty region log");