diff options
Diffstat (limited to 'drivers/block/null_blk/null_blk.h')
| -rw-r--r-- | drivers/block/null_blk/null_blk.h | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h new file mode 100644 index 000000000..94ff68052 --- /dev/null +++ b/drivers/block/null_blk/null_blk.h @@ -0,0 +1,179 @@ +/* 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_item item; + 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); +#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; +} +#define null_report_zones NULL +#endif /* CONFIG_BLK_DEV_ZONED */ +#endif /* __NULL_BLK_H */ |