275 static void null_del_dev(struct nullb *nullb);
277 static struct nullb *null_find_dev_by_name(const char *name);
382 	if (!dev->nullb)  in nullb_update_nr_hw_queues()
407 	set = dev->nullb->tag_set;  in nullb_update_nr_hw_queues()
513 			null_del_dev(dev->nullb);  in nullb_device_power_store()
702 		null_del_dev(dev->nullb);  in nullb_group_drop_item()
762 static inline int null_cache_active(struct nullb *nullb)  in null_cache_active()  argument
764 	return test_bit(NULLB_DEV_FL_CACHE, &nullb->dev->flags);  in null_cache_active()
890 static void null_free_sector(struct nullb *nullb, sector_t sector,  in null_free_sector()  argument
898 	root = is_cache ? &nullb->dev->cache : &nullb->dev->data;  in null_free_sector()
911 				nullb->dev->curr_cache -= PAGE_SIZE;  in null_free_sector()
916 static struct nullb_page *null_radix_tree_insert(struct nullb *nullb, u64 idx,  in null_radix_tree_insert()  argument
921 	root = is_cache ? &nullb->dev->cache : &nullb->dev->data;  in null_radix_tree_insert()
928 		nullb->dev->curr_cache += PAGE_SIZE;  in null_radix_tree_insert()
962 static struct nullb_page *__null_lookup_page(struct nullb *nullb,  in __null_lookup_page()  argument
973 	root = is_cache ? &nullb->dev->cache : &nullb->dev->data;  in __null_lookup_page()
983 static struct nullb_page *null_lookup_page(struct nullb *nullb,  in null_lookup_page()  argument
989 		page = __null_lookup_page(nullb, sector, for_write, true);  in null_lookup_page()
992 	return __null_lookup_page(nullb, sector, for_write, false);  in null_lookup_page()
995 static struct nullb_page *null_insert_page(struct nullb *nullb,  in null_insert_page()  argument
997 	__releases(&nullb->lock)  in null_insert_page()
998 	__acquires(&nullb->lock)  in null_insert_page()
1003 	t_page = null_lookup_page(nullb, sector, true, ignore_cache);  in null_insert_page()
1007 	spin_unlock_irq(&nullb->lock);  in null_insert_page()
1016 	spin_lock_irq(&nullb->lock);  in null_insert_page()
1019 	t_page = null_radix_tree_insert(nullb, idx, t_page, !ignore_cache);  in null_insert_page()
1026 	spin_lock_irq(&nullb->lock);  in null_insert_page()
1027 	return null_lookup_page(nullb, sector, true, ignore_cache);  in null_insert_page()
1030 static int null_flush_cache_page(struct nullb *nullb, struct nullb_page *c_page)  in null_flush_cache_page()  argument
1040 	t_page = null_insert_page(nullb, idx << PAGE_SECTORS_SHIFT, true);  in null_flush_cache_page()
1046 			ret = radix_tree_delete_item(&nullb->dev->data,  in null_flush_cache_page()
1060 			i += (nullb->dev->blocksize >> SECTOR_SHIFT)) {  in null_flush_cache_page()
1064 				nullb->dev->blocksize);  in null_flush_cache_page()
1072 	ret = radix_tree_delete_item(&nullb->dev->cache, idx, c_page);  in null_flush_cache_page()
1074 	nullb->dev->curr_cache -= PAGE_SIZE;  in null_flush_cache_page()
1079 static int null_make_cache_space(struct nullb *nullb, unsigned long n)  in null_make_cache_space()  argument
1086 	if ((nullb->dev->cache_size * 1024 * 1024) >  in null_make_cache_space()
1087 	     nullb->dev->curr_cache + n || nullb->dev->curr_cache == 0)  in null_make_cache_space()
1090 	nr_pages = radix_tree_gang_lookup(&nullb->dev->cache,  in null_make_cache_space()
1091 			(void **)c_pages, nullb->cache_flush_pos, FREE_BATCH);  in null_make_cache_space()
1097 		nullb->cache_flush_pos = c_pages[i]->page->private;  in null_make_cache_space()
1112 		err = null_flush_cache_page(nullb, c_pages[i]);  in null_make_cache_space()
1121 			nullb->cache_flush_pos = 0;  in null_make_cache_space()
1124 			spin_unlock_irq(&nullb->lock);  in null_make_cache_space()
1125 			spin_lock_irq(&nullb->lock);  in null_make_cache_space()
1132 static blk_status_t copy_to_nullb(struct nullb *nullb, void *source,  in copy_to_nullb()  argument
1140 		temp = min3(nullb->dev->blocksize, n - count,  in copy_to_nullb()
1144 		if (null_cache_active(nullb) && !is_fua)  in copy_to_nullb()
1145 			null_make_cache_space(nullb, PAGE_SIZE);  in copy_to_nullb()
1147 		t_page = null_insert_page(nullb, sector,  in copy_to_nullb()
1148 			!null_cache_active(nullb) || is_fua);  in copy_to_nullb()
1158 			null_free_sector(nullb, sector, true);  in copy_to_nullb()
1166 static void copy_from_nullb(struct nullb *nullb, void *dest, loff_t pos,  in copy_from_nullb()  argument
1174 		temp = min3(nullb->dev->blocksize, n - count,  in copy_from_nullb()
1178 		t_page = null_lookup_page(nullb, sector, false,  in copy_from_nullb()
1179 			!null_cache_active(nullb));  in copy_from_nullb()
1194 	struct nullb *nullb = dev->nullb;  in null_handle_discard()  local
1198 	spin_lock_irq(&nullb->lock);  in null_handle_discard()
1201 		null_free_sector(nullb, sector, false);  in null_handle_discard()
1202 		if (null_cache_active(nullb))  in null_handle_discard()
1203 			null_free_sector(nullb, sector, true);  in null_handle_discard()
1207 	spin_unlock_irq(&nullb->lock);  in null_handle_discard()
1212 static blk_status_t null_handle_flush(struct nullb *nullb)  in null_handle_flush()  argument
1216 	if (!null_cache_active(nullb))  in null_handle_flush()
1219 	spin_lock_irq(&nullb->lock);  in null_handle_flush()
1221 		err = null_make_cache_space(nullb,  in null_handle_flush()
1222 			nullb->dev->cache_size * 1024 * 1024);  in null_handle_flush()
1223 		if (err || nullb->dev->curr_cache == 0)  in null_handle_flush()
1227 	WARN_ON(!radix_tree_empty(&nullb->dev->cache));  in null_handle_flush()
1228 	spin_unlock_irq(&nullb->lock);  in null_handle_flush()
1232 static blk_status_t null_transfer(struct nullb *nullb, struct page *page,  in null_transfer()  argument
1236 	struct nullb_device *dev = nullb->dev;  in null_transfer()
1244 			valid_len = null_zone_valid_read_len(nullb,  in null_transfer()
1251 			copy_from_nullb(nullb, p, pos, valid_len);  in null_transfer()
1261 		err = copy_to_nullb(nullb, p, pos, len, is_fua);  in null_transfer()
1276 	struct nullb *nullb = cmd->nq->dev->nullb;  in null_handle_data_transfer()  local
1285 	spin_lock_irq(&nullb->lock);  in null_handle_data_transfer()
1290 		err = null_transfer(nullb, bvec.bv_page, len, bvec.bv_offset,  in null_handle_data_transfer()
1300 	spin_unlock_irq(&nullb->lock);  in null_handle_data_transfer()
1308 	struct nullb *nullb = dev->nullb;  in null_handle_throttled()  local
1312 	if (!hrtimer_active(&nullb->bw_timer))  in null_handle_throttled()
1313 		hrtimer_restart(&nullb->bw_timer);  in null_handle_throttled()
1315 	if (atomic_long_sub_return(blk_rq_bytes(rq), &nullb->cur_bytes) < 0) {  in null_handle_throttled()
1316 		blk_mq_stop_hw_queues(nullb->q);  in null_handle_throttled()
1318 		if (atomic_long_read(&nullb->cur_bytes) > 0)  in null_handle_throttled()
1319 			blk_mq_start_stopped_hw_queues(nullb->q, true);  in null_handle_throttled()
1436 	struct nullb *nullb = dev->nullb;  in null_handle_cmd()  local
1440 		cmd->error = null_handle_flush(nullb);  in null_handle_cmd()
1459 	struct nullb *nullb = container_of(timer, struct nullb, bw_timer);  in nullb_bwtimer_fn()  local
1461 	unsigned int mbps = nullb->dev->mbps;  in nullb_bwtimer_fn()
1463 	if (atomic_long_read(&nullb->cur_bytes) == mb_per_tick(mbps))  in nullb_bwtimer_fn()
1466 	atomic_long_set(&nullb->cur_bytes, mb_per_tick(mbps));  in nullb_bwtimer_fn()
1467 	blk_mq_start_stopped_hw_queues(nullb->q, true);  in nullb_bwtimer_fn()
1469 	hrtimer_forward_now(&nullb->bw_timer, timer_interval);  in nullb_bwtimer_fn()
1474 static void nullb_setup_bwtimer(struct nullb *nullb)  in nullb_setup_bwtimer()  argument
1478 	hrtimer_setup(&nullb->bw_timer, nullb_bwtimer_fn, CLOCK_MONOTONIC, HRTIMER_MODE_REL);  in nullb_setup_bwtimer()
1479 	atomic_long_set(&nullb->cur_bytes, mb_per_tick(nullb->dev->mbps));  in nullb_setup_bwtimer()
1480 	hrtimer_start(&nullb->bw_timer, timer_interval, HRTIMER_MODE_REL);  in nullb_setup_bwtimer()
1527 	struct nullb *nullb = set->driver_data;  in null_map_queues()  local
1532 	if (nullb) {  in null_map_queues()
1533 		struct nullb_device *dev = nullb->dev;  in null_map_queues()
1715 static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq)  in null_init_queue()  argument
1717 	nq->dev = nullb->dev;  in null_init_queue()
1725 	struct nullb *nullb = hctx->queue->queuedata;  in null_init_hctx()  local
1728 	if (should_init_hctx_fail(nullb->dev))  in null_init_hctx()
1731 	nq = &nullb->queues[hctx_idx];  in null_init_hctx()
1733 	null_init_queue(nullb, nq);  in null_init_hctx()
1748 static void null_del_dev(struct nullb *nullb)  in null_del_dev()  argument
1752 	if (!nullb)  in null_del_dev()
1755 	dev = nullb->dev;  in null_del_dev()
1757 	ida_free(&nullb_indexes, nullb->index);  in null_del_dev()
1759 	list_del_init(&nullb->list);  in null_del_dev()
1761 	del_gendisk(nullb->disk);  in null_del_dev()
1763 	if (test_bit(NULLB_DEV_FL_THROTTLED, &nullb->dev->flags)) {  in null_del_dev()
1764 		hrtimer_cancel(&nullb->bw_timer);  in null_del_dev()
1765 		atomic_long_set(&nullb->cur_bytes, LONG_MAX);  in null_del_dev()
1766 		blk_mq_start_stopped_hw_queues(nullb->q, true);  in null_del_dev()
1769 	put_disk(nullb->disk);  in null_del_dev()
1770 	if (nullb->tag_set == &nullb->__tag_set)  in null_del_dev()
1771 		blk_mq_free_tag_set(nullb->tag_set);  in null_del_dev()
1772 	kfree(nullb->queues);  in null_del_dev()
1773 	if (null_cache_active(nullb))  in null_del_dev()
1774 		null_free_device_storage(nullb->dev, true);  in null_del_dev()
1775 	kfree(nullb);  in null_del_dev()
1776 	dev->nullb = NULL;  in null_del_dev()
1779 static void null_config_discard(struct nullb *nullb, struct queue_limits *lim)  in null_config_discard()  argument
1781 	if (nullb->dev->discard == false)  in null_config_discard()
1784 	if (!nullb->dev->memory_backed) {  in null_config_discard()
1785 		nullb->dev->discard = false;  in null_config_discard()
1790 	if (nullb->dev->zoned) {  in null_config_discard()
1791 		nullb->dev->discard = false;  in null_config_discard()
1804 static int setup_queues(struct nullb *nullb)  in setup_queues()  argument
1811 	nullb->queues = kcalloc(nqueues, sizeof(struct nullb_queue),  in setup_queues()
1813 	if (!nullb->queues)  in setup_queues()
1855 static int null_setup_tagset(struct nullb *nullb)  in null_setup_tagset()  argument
1857 	if (nullb->dev->shared_tags) {  in null_setup_tagset()
1858 		nullb->tag_set = &tag_set;  in null_setup_tagset()
1862 	nullb->tag_set = &nullb->__tag_set;  in null_setup_tagset()
1863 	nullb->tag_set->driver_data = nullb;  in null_setup_tagset()
1864 	nullb->tag_set->nr_hw_queues = nullb->dev->submit_queues;  in null_setup_tagset()
1865 	nullb->tag_set->queue_depth = nullb->dev->hw_queue_depth;  in null_setup_tagset()
1866 	nullb->tag_set->numa_node = nullb->dev->home_node;  in null_setup_tagset()
1867 	if (nullb->dev->no_sched)  in null_setup_tagset()
1868 		nullb->tag_set->flags |= BLK_MQ_F_NO_SCHED_BY_DEFAULT;  in null_setup_tagset()
1869 	if (nullb->dev->shared_tag_bitmap)  in null_setup_tagset()
1870 		nullb->tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;  in null_setup_tagset()
1871 	if (nullb->dev->blocking)  in null_setup_tagset()
1872 		nullb->tag_set->flags |= BLK_MQ_F_BLOCKING;  in null_setup_tagset()
1873 	return null_init_tag_set(nullb->tag_set, nullb->dev->poll_queues);  in null_setup_tagset()
1955 	struct nullb *nullb;  in null_add_dev()  local
1962 	nullb = kzalloc_node(sizeof(*nullb), GFP_KERNEL, dev->home_node);  in null_add_dev()
1963 	if (!nullb) {  in null_add_dev()
1967 	nullb->dev = dev;  in null_add_dev()
1968 	dev->nullb = nullb;  in null_add_dev()
1970 	spin_lock_init(&nullb->lock);  in null_add_dev()
1972 	rv = setup_queues(nullb);  in null_add_dev()
1976 	rv = null_setup_tagset(nullb);  in null_add_dev()
1982 	null_config_discard(nullb, &lim);  in null_add_dev()
1990 		set_bit(NULLB_DEV_FL_CACHE, &nullb->dev->flags);  in null_add_dev()
1999 	nullb->disk = blk_mq_alloc_disk(nullb->tag_set, &lim, nullb);  in null_add_dev()
2000 	if (IS_ERR(nullb->disk)) {  in null_add_dev()
2001 		rv = PTR_ERR(nullb->disk);  in null_add_dev()
2004 	nullb->q = nullb->disk->queue;  in null_add_dev()
2008 		nullb_setup_bwtimer(nullb);  in null_add_dev()
2011 	nullb->q->queuedata = nullb;  in null_add_dev()
2017 	nullb->index = rv;  in null_add_dev()
2022 		snprintf(nullb->disk_name, sizeof(nullb->disk_name),  in null_add_dev()
2025 		sprintf(nullb->disk_name, "nullb%d", nullb->index);  in null_add_dev()
2028 	set_capacity(nullb->disk,  in null_add_dev()
2029 		((sector_t)nullb->dev->size * SZ_1M) >> SECTOR_SHIFT);  in null_add_dev()
2030 	nullb->disk->major = null_major;  in null_add_dev()
2031 	nullb->disk->first_minor = nullb->index;  in null_add_dev()
2032 	nullb->disk->minors = 1;  in null_add_dev()
2033 	nullb->disk->fops = &null_ops;  in null_add_dev()
2034 	nullb->disk->private_data = nullb;  in null_add_dev()
2035 	strscpy(nullb->disk->disk_name, nullb->disk_name);  in null_add_dev()
2037 	if (nullb->dev->zoned) {  in null_add_dev()
2038 		rv = null_register_zoned_dev(nullb);  in null_add_dev()
2043 	rv = add_disk(nullb->disk);  in null_add_dev()
2047 	list_add_tail(&nullb->list, &nullb_list);  in null_add_dev()
2049 	pr_info("disk %s created\n", nullb->disk_name);  in null_add_dev()
2054 	ida_free(&nullb_indexes, nullb->index);  in null_add_dev()
2056 	put_disk(nullb->disk);  in null_add_dev()
2060 	if (nullb->tag_set == &nullb->__tag_set)  in null_add_dev()
2061 		blk_mq_free_tag_set(nullb->tag_set);  in null_add_dev()
2063 	kfree(nullb->queues);  in null_add_dev()
2065 	kfree(nullb);  in null_add_dev()
2066 	dev->nullb = NULL;  in null_add_dev()
2071 static struct nullb *null_find_dev_by_name(const char *name)  in null_find_dev_by_name()
2073 	struct nullb *nullb = NULL, *nb;  in null_find_dev_by_name()  local
2078 			nullb = nb;  in null_find_dev_by_name()
2084 	return nullb;  in null_find_dev_by_name()
2107 static void null_destroy_dev(struct nullb *nullb)  in null_destroy_dev()  argument
2109 	struct nullb_device *dev = nullb->dev;  in null_destroy_dev()
2111 	null_del_dev(nullb);  in null_destroy_dev()
2120 	struct nullb *nullb;  in null_init()  local
2179 		nullb = list_entry(nullb_list.next, struct nullb, list);  in null_init()
2180 		null_destroy_dev(nullb);  in null_init()
2190 	struct nullb *nullb;  in null_exit()  local
2198 		nullb = list_entry(nullb_list.next, struct nullb, list);  in null_exit()
2199 		null_destroy_dev(nullb);  in null_exit()