#ifndef _BCACHE_WRITEBACK_H#define _BCACHE_WRITEBACK_H #define CUTOFF_WRITEBACK	40#define CUTOFF_WRITEBACK_SYNC	70 static inline uint64_t bcache_dev_sectors_dirty(struct bcache_device *d){	uint64_t i, ret = 0; 	for (i = 0; i < d->nr_stripes; i++)		ret += atomic_read(d->stripe_sectors_dirty + i); 	return ret;} static inline unsigned offset_to_stripe(struct bcache_device *d,					uint64_t offset){	do_div(offset, d->stripe_size);	return offset;} static inline bool bcache_dev_stripe_dirty(struct cached_dev *dc,					   uint64_t offset,					   unsigned nr_sectors){	unsigned stripe = offset_to_stripe(&dc->disk, offset); 	while (1) {		if (atomic_read(dc->disk.stripe_sectors_dirty + stripe))			return true; 		if (nr_sectors <= dc->disk.stripe_size)			return false; 		nr_sectors -= dc->disk.stripe_size;		stripe++;	}} static inline bool should_writeback(struct cached_dev *dc, struct bio *bio,				    unsigned cache_mode, bool would_skip){	unsigned in_use = dc->disk.c->gc_stats.in_use; 	if (cache_mode != CACHE_MODE_WRITEBACK ||	    test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) ||	    in_use > CUTOFF_WRITEBACK_SYNC)		return false; 	if (dc->partial_stripes_expensive &&	    bcache_dev_stripe_dirty(dc, bio->bi_sector,				    bio_sectors(bio)))		return true; 	if (would_skip)		return false; 	return bio->bi_rw & REQ_SYNC ||		in_use <= CUTOFF_WRITEBACK;} static inline void bch_writeback_queue(struct cached_dev *dc){	wake_up_process(dc->writeback_thread);} static inline void bch_writeback_add(struct cached_dev *dc){	if (!atomic_read(&dc->has_dirty) &&	    !atomic_xchg(&dc->has_dirty, 1)) {		atomic_inc(&dc->count); 		if (BDEV_STATE(&dc->sb) != BDEV_STATE_DIRTY) {			SET_BDEV_STATE(&dc->sb, BDEV_STATE_DIRTY);			/* XXX: should do this synchronously */			bch_write_bdev_super(dc, NULL);		} 		bch_writeback_queue(dc);	}} void bcache_dev_sectors_dirty_add(struct cache_set *, unsigned, uint64_t, int); void bch_sectors_dirty_init(struct cached_dev *dc);int bch_cached_dev_writeback_init(struct cached_dev *); #endif