209 	struct dm_snapshot *snap;  member
443 static int __find_snapshots_sharing_cow(struct dm_snapshot *snap,  in __find_snapshots_sharing_cow()  argument
453 	o = __lookup_origin(snap->origin->bdev);  in __find_snapshots_sharing_cow()
460 		if (!bdev_equal(s->cow->bdev, snap->cow->bdev))  in __find_snapshots_sharing_cow()
484 static int __validate_exception_handover(struct dm_snapshot *snap)  in __validate_exception_handover()  argument
490 	if ((__find_snapshots_sharing_cow(snap, &snap_src, &snap_dest,  in __validate_exception_handover()
493 		snap->ti->error = "Snapshot cow pairing for exception "  in __validate_exception_handover()
508 	if (!dm_target_is_snapshot_merge(snap->ti))  in __validate_exception_handover()
515 		snap->ti->error = "A snapshot is already merging.";  in __validate_exception_handover()
521 		snap->ti->error = "Snapshot exception store does not "  in __validate_exception_handover()
548 static int register_snapshot(struct dm_snapshot *snap)  in register_snapshot()  argument
551 	struct block_device *bdev = snap->origin->bdev;  in register_snapshot()
560 	r = __validate_exception_handover(snap);  in register_snapshot()
580 	__insert_snapshot(o, snap);  in register_snapshot()
742 	pe->snap = s;  in alloc_pending_exception()
749 	struct dm_snapshot *s = pe->snap;  in free_pending_exception()
851 	struct dm_snapshot *snap;  in __minimum_chunk_size()  local
855 		list_for_each_entry(snap, &o->snapshots, list)  in __minimum_chunk_size()
857 						  snap->store->chunk_size);  in __minimum_chunk_size()
1449 	snap_dest->store->snap = snap_dest;  in __handover_exceptions()
1450 	snap_src->store->snap = snap_src;  in __handover_exceptions()
1640 	struct dm_snapshot *s = pe->snap;  in pending_complete()
1726 	struct dm_snapshot *s = pe->snap;  in complete_exception()
1740 	struct dm_snapshot *s = pe->snap;  in copy_callback()
1789 	struct dm_snapshot *s = pe->snap;  in start_copy()
1819 	struct dm_snapshot *s = pe->snap;  in start_full_bio()
2314 	struct dm_snapshot *snap = ti->private;  in snapshot_status()  local
2320 		down_write(&snap->lock);  in snapshot_status()
2322 		if (!snap->valid)  in snapshot_status()
2324 		else if (snap->merge_failed)  in snapshot_status()
2326 		else if (snap->snapshot_overflowed)  in snapshot_status()
2329 			if (snap->store->type->usage) {  in snapshot_status()
2332 				snap->store->type->usage(snap->store,  in snapshot_status()
2345 		up_write(&snap->lock);  in snapshot_status()
2355 		DMEMIT("%s %s", snap->origin->name, snap->cow->name);  in snapshot_status()
2356 		sz += snap->store->type->status(snap->store, type, result + sz,  in snapshot_status()
2358 		num_features = snap->discard_zeroes_cow + snap->discard_passdown_origin;  in snapshot_status()
2361 			if (snap->discard_zeroes_cow)  in snapshot_status()
2363 			if (snap->discard_passdown_origin)  in snapshot_status()
2373 	struct dm_snapshot *snap = ti->private;  in snapshot_iterate_devices()  local
2376 	r = fn(ti, snap->origin, 0, ti->len, data);  in snapshot_iterate_devices()
2379 		r = fn(ti, snap->cow, 0, get_dev_size(snap->cow->bdev), data);  in snapshot_iterate_devices()
2386 	struct dm_snapshot *snap = ti->private;  in snapshot_io_hints()  local
2388 	if (snap->discard_zeroes_cow) {  in snapshot_io_hints()
2393 		(void) __find_snapshots_sharing_cow(snap, &snap_src, &snap_dest, NULL);  in snapshot_io_hints()
2395 			snap = snap_src;  in snapshot_io_hints()
2398 		limits->discard_granularity = snap->store->chunk_size;  in snapshot_io_hints()
2399 		limits->max_discard_sectors = snap->store->chunk_size;  in snapshot_io_hints()
2423 	struct dm_snapshot *snap;  in __origin_write()  local
2432 	list_for_each_entry (snap, snapshots, list) {  in __origin_write()
2437 		if (dm_target_is_snapshot_merge(snap->ti))  in __origin_write()
2441 		if (sector >= dm_table_get_size(snap->ti->table))  in __origin_write()
2448 		chunk = sector_to_chunk(snap->store, sector);  in __origin_write()
2449 		dm_exception_table_lock_init(snap, chunk, &lock);  in __origin_write()
2451 		down_read(&snap->lock);  in __origin_write()
2455 		if (!snap->valid || !snap->active)  in __origin_write()
2458 		pe = __lookup_pending_exception(snap, chunk);  in __origin_write()
2465 			e = dm_lookup_exception(&snap->complete, chunk);  in __origin_write()
2470 			pe = alloc_pending_exception(snap);  in __origin_write()
2473 			pe2 = __lookup_pending_exception(snap, chunk);  in __origin_write()
2476 				e = dm_lookup_exception(&snap->complete, chunk);  in __origin_write()
2482 				pe = __insert_pending_exception(snap, pe, chunk);  in __origin_write()
2485 					up_read(&snap->lock);  in __origin_write()
2487 					invalidate_snapshot(snap, -ENOMEM);  in __origin_write()
2520 		up_read(&snap->lock);  in __origin_write()