[linux-2.6-block.git] / drivers / block / null_blk / null_blk.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __BLK_NULL_BLK_H
#define __BLK_NULL_BLK_H

#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/hrtimer.h>
#include <linux/configfs.h>
#include <linux/badblocks.h>
#include <linux/fault-inject.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>

struct nullb_cmd {
	blk_status_t error;
	bool fake_timeout;
	struct nullb_queue *nq;
	struct hrtimer timer;
};

struct nullb_queue {
	struct nullb_device *dev;
	unsigned int requeue_selection;

	struct list_head poll_list;
	spinlock_t poll_lock;
};

struct nullb_zone {
	/*
	 * Zone lock to prevent concurrent modification of a zone write
	 * pointer position and condition: with memory backing, a write
	 * command execution may sleep on memory allocation. For this case,
	 * use mutex as the zone lock. Otherwise, use the spinlock for
	 * locking the zone.
	 */
	union {
		spinlock_t spinlock;
		struct mutex mutex;
	};
	enum blk_zone_type type;
	enum blk_zone_cond cond;
	sector_t start;
	sector_t wp;
	unsigned int len;
	unsigned int capacity;
};

struct nullb_device {
	struct nullb *nullb;
	struct config_group group;
#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION
	struct fault_config timeout_config;
	struct fault_config requeue_config;
	struct fault_config init_hctx_fault_config;
#endif
	struct radix_tree_root data; /* data stored in the disk */
	struct radix_tree_root cache; /* disk cache data */
	unsigned long flags; /* device flags */
	unsigned int curr_cache;
	struct badblocks badblocks;

	unsigned int nr_zones;
	unsigned int nr_zones_imp_open;
	unsigned int nr_zones_exp_open;
	unsigned int nr_zones_closed;
	unsigned int imp_close_zone_no;
	struct nullb_zone *zones;
	sector_t zone_size_sects;
	bool need_zone_res_mgmt;
	spinlock_t zone_res_lock;

	unsigned long size; /* device size in MB */
	unsigned long completion_nsec; /* time in ns to complete a request */
	unsigned long cache_size; /* disk cache size in MB */
	unsigned long zone_size; /* zone size in MB if device is zoned */
	unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
	unsigned int zone_nr_conv; /* number of conventional zones */
	unsigned int zone_max_open; /* max number of open zones */
	unsigned int zone_max_active; /* max number of active zones */
	unsigned int zone_append_max_sectors; /* Max sectors per zone append command */
	unsigned int submit_queues; /* number of submission queues */
	unsigned int prev_submit_queues; /* number of submission queues before change */
	unsigned int poll_queues; /* number of IOPOLL submission queues */
	unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */
	unsigned int home_node; /* home node for the device */
	unsigned int queue_mode; /* block interface */
	unsigned int blocksize; /* block size */
	unsigned int max_sectors; /* Max sectors per command */
	unsigned int irqmode; /* IRQ completion handler */
	unsigned int hw_queue_depth; /* queue depth */
	unsigned int index; /* index of the disk, only valid with a disk */
	unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
	bool blocking; /* blocking blk-mq device */
	bool use_per_node_hctx; /* use per-node allocation for hardware context */
	bool power; /* power on/off the device */
	bool memory_backed; /* if data is stored in memory */
	bool discard; /* if support discard */
	bool zoned; /* if device is zoned */
	bool zone_full; /* Initialize zones to be full */
	bool virt_boundary; /* virtual boundary on/off for the device */
	bool no_sched; /* no IO scheduler for the device */
	bool shared_tags; /* share tag set between devices for blk-mq */
	bool shared_tag_bitmap; /* use hostwide shared tags */
	bool fua; /* Support FUA */
};

struct nullb {
	struct nullb_device *dev;
	struct list_head list;
	unsigned int index;
	struct request_queue *q;
	struct gendisk *disk;
	struct blk_mq_tag_set *tag_set;
	struct blk_mq_tag_set __tag_set;
	atomic_long_t cur_bytes;
	struct hrtimer bw_timer;
	unsigned long cache_flush_pos;
	spinlock_t lock;

	struct nullb_queue *queues;
	char disk_name[DISK_NAME_LEN];
};

blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector,
				 sector_t nr_sectors);
blk_status_t null_process_cmd(struct nullb_cmd *cmd, enum req_op op,
			      sector_t sector, unsigned int nr_sectors);

#ifdef CONFIG_BLK_DEV_ZONED
int null_init_zoned_dev(struct nullb_device *dev, struct queue_limits *lim);
int null_register_zoned_dev(struct nullb *nullb);
void null_free_zoned_dev(struct nullb_device *dev);
int null_report_zones(struct gendisk *disk, sector_t sector,
		      unsigned int nr_zones, report_zones_cb cb, void *data);
blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op,
				    sector_t sector, sector_t nr_sectors);
size_t null_zone_valid_read_len(struct nullb *nullb,
				sector_t sector, unsigned int len);
ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
			size_t count, enum blk_zone_cond cond);
#else
static inline int null_init_zoned_dev(struct nullb_device *dev,
		struct queue_limits *lim)
{
	pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
	return -EINVAL;
}
static inline int null_register_zoned_dev(struct nullb *nullb)
{
	return -ENODEV;
}
static inline void null_free_zoned_dev(struct nullb_device *dev) {}
static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
			enum req_op op, sector_t sector, sector_t nr_sectors)
{
	return BLK_STS_NOTSUPP;
}
static inline size_t null_zone_valid_read_len(struct nullb *nullb,
					      sector_t sector,
					      unsigned int len)
{
	return len;
}
static inline ssize_t zone_cond_store(struct nullb_device *dev,
				      const char *page, size_t count,
				      enum blk_zone_cond cond)
{
	return -EOPNOTSUPP;
}
#define null_report_zones	NULL
#endif /* CONFIG_BLK_DEV_ZONED */
#endif /* __NULL_BLK_H */
Commit	Line	Data
6dad38d3 MB	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef __BLK_NULL_BLK_H
	3	#define __BLK_NULL_BLK_H
	4
9c7eddf1 AA	5	#undef pr_fmt
	6	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	7
6dad38d3 MB	8	#include <linux/blkdev.h>
	9	#include <linux/slab.h>
	10	#include <linux/blk-mq.h>
	11	#include <linux/hrtimer.h>
	12	#include <linux/configfs.h>
	13	#include <linux/badblocks.h>
	14	#include <linux/fault-inject.h>
2b8b7ed7 DLM	15	#include <linux/spinlock.h>
2b8b7ed7 DLM	16	#include <linux/mutex.h>
6dad38d3 MB	17
6dad38d3 MB	18	struct nullb_cmd {
6dad38d3	19	blk_status_t error;
8ba816b2	20	bool fake_timeout;
6dad38d3 MB	21	struct nullb_queue *nq;
	22	struct hrtimer timer;
	23	};
	24
	25	struct nullb_queue {
6dad38d3 MB	26	struct nullb_device *dev;
	27	unsigned int requeue_selection;
	28
0a593fbb JA	29	struct list_head poll_list;
0a593fbb JA	30	spinlock_t poll_lock;
6dad38d3 MB	31	};
6dad38d3 MB	32
2b8b7ed7 DLM	33	struct nullb_zone {
	34	/*
	35	* Zone lock to prevent concurrent modification of a zone write
	36	* pointer position and condition: with memory backing, a write
	37	* command execution may sleep on memory allocation. For this case,
	38	* use mutex as the zone lock. Otherwise, use the spinlock for
	39	* locking the zone.
	40	*/
	41	union {
	42	spinlock_t spinlock;
	43	struct mutex mutex;
	44	};
	45	enum blk_zone_type type;
	46	enum blk_zone_cond cond;
	47	sector_t start;
	48	sector_t wp;
	49	unsigned int len;
	50	unsigned int capacity;
	51	};
	52
6dad38d3 MB	53	struct nullb_device {
6dad38d3 MB	54	struct nullb *nullb;
bb4c19e0 AM	55	struct config_group group;
	56	#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION
	57	struct fault_config timeout_config;
	58	struct fault_config requeue_config;
	59	struct fault_config init_hctx_fault_config;
	60	#endif
6dad38d3 MB	61	struct radix_tree_root data; /* data stored in the disk */
	62	struct radix_tree_root cache; /* disk cache data */
	63	unsigned long flags; /* device flags */
	64	unsigned int curr_cache;
	65	struct badblocks badblocks;
	66
ca4b2a01	67	unsigned int nr_zones;
dc4d137e NC	68	unsigned int nr_zones_imp_open;
	69	unsigned int nr_zones_exp_open;
	70	unsigned int nr_zones_closed;
2e8c6e0e	71	unsigned int imp_close_zone_no;
2b8b7ed7	72	struct nullb_zone *zones;
ca4b2a01	73	sector_t zone_size_sects;
2b8b7ed7 DLM	74	bool need_zone_res_mgmt;
2b8b7ed7 DLM	75	spinlock_t zone_res_lock;
ca4b2a01	76
6dad38d3 MB	77	unsigned long size; /* device size in MB */
	78	unsigned long completion_nsec; /* time in ns to complete a request */
	79	unsigned long cache_size; /* disk cache size in MB */
ca4b2a01	80	unsigned long zone_size; /* zone size in MB if device is zoned */
089565fb	81	unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
ea2c18e1	82	unsigned int zone_nr_conv; /* number of conventional zones */
dc4d137e NC	83	unsigned int zone_max_open; /* max number of open zones */
dc4d137e NC	84	unsigned int zone_max_active; /* max number of active zones */
997a1f08	85	unsigned int zone_append_max_sectors; /* Max sectors per zone append command */
6dad38d3	86	unsigned int submit_queues; /* number of submission queues */
15dfc662	87	unsigned int prev_submit_queues; /* number of submission queues before change */
0a593fbb	88	unsigned int poll_queues; /* number of IOPOLL submission queues */
15dfc662	89	unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */
6dad38d3 MB	90	unsigned int home_node; /* home node for the device */
	91	unsigned int queue_mode; /* block interface */
	92	unsigned int blocksize; /* block size */
ea17fd35	93	unsigned int max_sectors; /* Max sectors per command */
6dad38d3 MB	94	unsigned int irqmode; /* IRQ completion handler */
	95	unsigned int hw_queue_depth; /* queue depth */
	96	unsigned int index; /* index of the disk, only valid with a disk */
	97	unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
	98	bool blocking; /* blocking blk-mq device */
	99	bool use_per_node_hctx; /* use per-node allocation for hardware context */
	100	bool power; /* power on/off the device */
	101	bool memory_backed; /* if data is stored in memory */
	102	bool discard; /* if support discard */
ca4b2a01	103	bool zoned; /* if device is zoned */
f4d5dc33	104	bool zone_full; /* Initialize zones to be full */
cee1b215	105	bool virt_boundary; /* virtual boundary on/off for the device */
7012eef5	106	bool no_sched; /* no IO scheduler for the device */
14509b74	107	bool shared_tags; /* share tag set between devices for blk-mq */
7012eef5	108	bool shared_tag_bitmap; /* use hostwide shared tags */
f4f84586	109	bool fua; /* Support FUA */
6dad38d3 MB	110	};
	111
	112	struct nullb {
	113	struct nullb_device *dev;
	114	struct list_head list;
	115	unsigned int index;
	116	struct request_queue *q;
	117	struct gendisk *disk;
	118	struct blk_mq_tag_set *tag_set;
	119	struct blk_mq_tag_set __tag_set;
6dad38d3 MB	120	atomic_long_t cur_bytes;
	121	struct hrtimer bw_timer;
	122	unsigned long cache_flush_pos;
	123	spinlock_t lock;
	124
	125	struct nullb_queue *queues;
6dad38d3 MB	126	char disk_name[DISK_NAME_LEN];
6dad38d3 MB	127	};
ca4b2a01	128
0ec4d913 DLM	129	blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector,
0ec4d913 DLM	130	sector_t nr_sectors);
ff07a02e BVA	131	blk_status_t null_process_cmd(struct nullb_cmd *cmd, enum req_op op,
ff07a02e BVA	132	sector_t sector, unsigned int nr_sectors);
9dd44c7e	133
ca4b2a01	134	#ifdef CONFIG_BLK_DEV_ZONED
e440626b	135	int null_init_zoned_dev(struct nullb_device dev, struct queue_limits lim);
d205bde7 DLM	136	int null_register_zoned_dev(struct nullb *nullb);
d205bde7 DLM	137	void null_free_zoned_dev(struct nullb_device *dev);
7fc8fb51	138	int null_report_zones(struct gendisk *disk, sector_t sector,
d4100351	139	unsigned int nr_zones, report_zones_cb cb, void *data);
ff07a02e BVA	140	blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op,
ff07a02e BVA	141	sector_t sector, sector_t nr_sectors);
dd85b492 AJ	142	size_t null_zone_valid_read_len(struct nullb *nullb,
dd85b492 AJ	143	sector_t sector, unsigned int len);
d3a57388 SK	144	ssize_t zone_cond_store(struct nullb_device dev, const char page,
d3a57388 SK	145	size_t count, enum blk_zone_cond cond);
ca4b2a01	146	#else
d205bde7	147	static inline int null_init_zoned_dev(struct nullb_device *dev,
e440626b	148	struct queue_limits *lim)
ca4b2a01	149	{
9c7eddf1	150	pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
ca4b2a01 MB	151	return -EINVAL;
ca4b2a01 MB	152	}
d205bde7 DLM	153	static inline int null_register_zoned_dev(struct nullb *nullb)
	154	{
	155	return -ENODEV;
	156	}
	157	static inline void null_free_zoned_dev(struct nullb_device *dev) {}
9dd44c7e	158	static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
ff07a02e	159	enum req_op op, sector_t sector, sector_t nr_sectors)
b228ba1c	160	{
fceb5d1b	161	return BLK_STS_NOTSUPP;
b228ba1c	162	}
dd85b492 AJ	163	static inline size_t null_zone_valid_read_len(struct nullb *nullb,
	164	sector_t sector,
	165	unsigned int len)
	166	{
	167	return len;
	168	}
d3a57388 SK	169	static inline ssize_t zone_cond_store(struct nullb_device *dev,
	170	const char *page, size_t count,
	171	enum blk_zone_cond cond)
	172	{
	173	return -EOPNOTSUPP;
	174	}
7fc8fb51	175	#define null_report_zones NULL
ca4b2a01	176	#endif /* CONFIG_BLK_DEV_ZONED */
6dad38d3	177	#endif /* __NULL_BLK_H */