[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 {
	union {
		struct request *rq;
		struct bio *bio;
	};
	unsigned int tag;
	blk_status_t error;
	bool fake_timeout;
	struct nullb_queue *nq;
	struct hrtimer timer;
};

struct nullb_queue {
	unsigned long *tag_map;
	wait_queue_head_t wait;
	unsigned int queue_depth;
	struct nullb_device *dev;
	unsigned int requeue_selection;

	struct list_head poll_list;
	spinlock_t poll_lock;

	struct nullb_cmd *cmds;
};

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;
};

/* Queue modes */
enum {
	NULL_Q_BIO	= 0,
	NULL_Q_RQ	= 1,
	NULL_Q_MQ	= 2,
};

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 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 virt_boundary; /* virtual boundary on/off for the device */
	bool no_sched; /* no IO scheduler for the device */
	bool shared_tag_bitmap; /* use hostwide shared tags */
};

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;
	unsigned int queue_depth;
	atomic_long_t cur_bytes;
	struct hrtimer bw_timer;
	unsigned long cache_flush_pos;
	spinlock_t lock;

	struct nullb_queue *queues;
	unsigned int nr_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 request_queue *q);
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 request_queue *q)
{
	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 {
8ba816b2 YK	19	union {
	20	struct request *rq;
	21	struct bio *bio;
	22	};
6dad38d3 MB	23	unsigned int tag;
6dad38d3 MB	24	blk_status_t error;
8ba816b2	25	bool fake_timeout;
6dad38d3 MB	26	struct nullb_queue *nq;
	27	struct hrtimer timer;
	28	};
	29
	30	struct nullb_queue {
	31	unsigned long *tag_map;
	32	wait_queue_head_t wait;
	33	unsigned int queue_depth;
	34	struct nullb_device *dev;
	35	unsigned int requeue_selection;
	36
0a593fbb JA	37	struct list_head poll_list;
	38	spinlock_t poll_lock;
	39
6dad38d3 MB	40	struct nullb_cmd *cmds;
	41	};
	42
2b8b7ed7 DLM	43	struct nullb_zone {
	44	/*
	45	* Zone lock to prevent concurrent modification of a zone write
	46	* pointer position and condition: with memory backing, a write
	47	* command execution may sleep on memory allocation. For this case,
	48	* use mutex as the zone lock. Otherwise, use the spinlock for
	49	* locking the zone.
	50	*/
	51	union {
	52	spinlock_t spinlock;
	53	struct mutex mutex;
	54	};
	55	enum blk_zone_type type;
	56	enum blk_zone_cond cond;
	57	sector_t start;
	58	sector_t wp;
	59	unsigned int len;
	60	unsigned int capacity;
	61	};
	62
aacae8c4 DLM	63	/* Queue modes */
	64	enum {
	65	NULL_Q_BIO = 0,
	66	NULL_Q_RQ = 1,
	67	NULL_Q_MQ = 2,
	68	};
	69
6dad38d3 MB	70	struct nullb_device {
6dad38d3 MB	71	struct nullb *nullb;
bb4c19e0 AM	72	struct config_group group;
	73	#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION
	74	struct fault_config timeout_config;
	75	struct fault_config requeue_config;
	76	struct fault_config init_hctx_fault_config;
	77	#endif
6dad38d3 MB	78	struct radix_tree_root data; /* data stored in the disk */
	79	struct radix_tree_root cache; /* disk cache data */
	80	unsigned long flags; /* device flags */
	81	unsigned int curr_cache;
	82	struct badblocks badblocks;
	83
ca4b2a01	84	unsigned int nr_zones;
dc4d137e NC	85	unsigned int nr_zones_imp_open;
	86	unsigned int nr_zones_exp_open;
	87	unsigned int nr_zones_closed;
2e8c6e0e	88	unsigned int imp_close_zone_no;
2b8b7ed7	89	struct nullb_zone *zones;
ca4b2a01	90	sector_t zone_size_sects;
2b8b7ed7 DLM	91	bool need_zone_res_mgmt;
2b8b7ed7 DLM	92	spinlock_t zone_res_lock;
ca4b2a01	93
6dad38d3 MB	94	unsigned long size; /* device size in MB */
	95	unsigned long completion_nsec; /* time in ns to complete a request */
	96	unsigned long cache_size; /* disk cache size in MB */
ca4b2a01	97	unsigned long zone_size; /* zone size in MB if device is zoned */
089565fb	98	unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
ea2c18e1	99	unsigned int zone_nr_conv; /* number of conventional zones */
dc4d137e NC	100	unsigned int zone_max_open; /* max number of open zones */
dc4d137e NC	101	unsigned int zone_max_active; /* max number of active zones */
6dad38d3	102	unsigned int submit_queues; /* number of submission queues */
15dfc662	103	unsigned int prev_submit_queues; /* number of submission queues before change */
0a593fbb	104	unsigned int poll_queues; /* number of IOPOLL submission queues */
15dfc662	105	unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */
6dad38d3 MB	106	unsigned int home_node; /* home node for the device */
	107	unsigned int queue_mode; /* block interface */
	108	unsigned int blocksize; /* block size */
ea17fd35	109	unsigned int max_sectors; /* Max sectors per command */
6dad38d3 MB	110	unsigned int irqmode; /* IRQ completion handler */
	111	unsigned int hw_queue_depth; /* queue depth */
	112	unsigned int index; /* index of the disk, only valid with a disk */
	113	unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
	114	bool blocking; /* blocking blk-mq device */
	115	bool use_per_node_hctx; /* use per-node allocation for hardware context */
	116	bool power; /* power on/off the device */
	117	bool memory_backed; /* if data is stored in memory */
	118	bool discard; /* if support discard */
ca4b2a01	119	bool zoned; /* if device is zoned */
cee1b215	120	bool virt_boundary; /* virtual boundary on/off for the device */
7012eef5 VF	121	bool no_sched; /* no IO scheduler for the device */
7012eef5 VF	122	bool shared_tag_bitmap; /* use hostwide shared tags */
6dad38d3 MB	123	};
	124
	125	struct nullb {
	126	struct nullb_device *dev;
	127	struct list_head list;
	128	unsigned int index;
	129	struct request_queue *q;
	130	struct gendisk *disk;
	131	struct blk_mq_tag_set *tag_set;
	132	struct blk_mq_tag_set __tag_set;
	133	unsigned int queue_depth;
	134	atomic_long_t cur_bytes;
	135	struct hrtimer bw_timer;
	136	unsigned long cache_flush_pos;
	137	spinlock_t lock;
	138
	139	struct nullb_queue *queues;
	140	unsigned int nr_queues;
	141	char disk_name[DISK_NAME_LEN];
	142	};
ca4b2a01	143
0ec4d913 DLM	144	blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector,
0ec4d913 DLM	145	sector_t nr_sectors);
ff07a02e BVA	146	blk_status_t null_process_cmd(struct nullb_cmd *cmd, enum req_op op,
ff07a02e BVA	147	sector_t sector, unsigned int nr_sectors);
9dd44c7e	148
ca4b2a01	149	#ifdef CONFIG_BLK_DEV_ZONED
d205bde7 DLM	150	int null_init_zoned_dev(struct nullb_device dev, struct request_queue q);
	151	int null_register_zoned_dev(struct nullb *nullb);
	152	void null_free_zoned_dev(struct nullb_device *dev);
7fc8fb51	153	int null_report_zones(struct gendisk *disk, sector_t sector,
d4100351	154	unsigned int nr_zones, report_zones_cb cb, void *data);
ff07a02e BVA	155	blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op,
ff07a02e BVA	156	sector_t sector, sector_t nr_sectors);
dd85b492 AJ	157	size_t null_zone_valid_read_len(struct nullb *nullb,
dd85b492 AJ	158	sector_t sector, unsigned int len);
d3a57388 SK	159	ssize_t zone_cond_store(struct nullb_device dev, const char page,
d3a57388 SK	160	size_t count, enum blk_zone_cond cond);
ca4b2a01	161	#else
d205bde7 DLM	162	static inline int null_init_zoned_dev(struct nullb_device *dev,
d205bde7 DLM	163	struct request_queue *q)
ca4b2a01	164	{
9c7eddf1	165	pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
ca4b2a01 MB	166	return -EINVAL;
ca4b2a01 MB	167	}
d205bde7 DLM	168	static inline int null_register_zoned_dev(struct nullb *nullb)
	169	{
	170	return -ENODEV;
	171	}
	172	static inline void null_free_zoned_dev(struct nullb_device *dev) {}
9dd44c7e	173	static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
ff07a02e	174	enum req_op op, sector_t sector, sector_t nr_sectors)
b228ba1c	175	{
fceb5d1b	176	return BLK_STS_NOTSUPP;
b228ba1c	177	}
dd85b492 AJ	178	static inline size_t null_zone_valid_read_len(struct nullb *nullb,
	179	sector_t sector,
	180	unsigned int len)
	181	{
	182	return len;
	183	}
d3a57388 SK	184	static inline ssize_t zone_cond_store(struct nullb_device *dev,
	185	const char *page, size_t count,
	186	enum blk_zone_cond cond)
	187	{
	188	return -EOPNOTSUPP;
	189	}
7fc8fb51	190	#define null_report_zones NULL
ca4b2a01	191	#endif /* CONFIG_BLK_DEV_ZONED */
6dad38d3	192	#endif /* __NULL_BLK_H */