null_blk.h (5471B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __BLK_NULL_BLK_H 3#define __BLK_NULL_BLK_H 4 5#undef pr_fmt 6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 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> 15#include <linux/spinlock.h> 16#include <linux/mutex.h> 17 18struct nullb_cmd { 19 union { 20 struct request *rq; 21 struct bio *bio; 22 }; 23 unsigned int tag; 24 blk_status_t error; 25 bool fake_timeout; 26 struct nullb_queue *nq; 27 struct hrtimer timer; 28}; 29 30struct 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 37 struct list_head poll_list; 38 spinlock_t poll_lock; 39 40 struct nullb_cmd *cmds; 41}; 42 43struct 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 63/* Queue modes */ 64enum { 65 NULL_Q_BIO = 0, 66 NULL_Q_RQ = 1, 67 NULL_Q_MQ = 2, 68}; 69 70struct nullb_device { 71 struct nullb *nullb; 72 struct config_item item; 73 struct radix_tree_root data; /* data stored in the disk */ 74 struct radix_tree_root cache; /* disk cache data */ 75 unsigned long flags; /* device flags */ 76 unsigned int curr_cache; 77 struct badblocks badblocks; 78 79 unsigned int nr_zones; 80 unsigned int nr_zones_imp_open; 81 unsigned int nr_zones_exp_open; 82 unsigned int nr_zones_closed; 83 unsigned int imp_close_zone_no; 84 struct nullb_zone *zones; 85 sector_t zone_size_sects; 86 bool need_zone_res_mgmt; 87 spinlock_t zone_res_lock; 88 89 unsigned long size; /* device size in MB */ 90 unsigned long completion_nsec; /* time in ns to complete a request */ 91 unsigned long cache_size; /* disk cache size in MB */ 92 unsigned long zone_size; /* zone size in MB if device is zoned */ 93 unsigned long zone_capacity; /* zone capacity in MB if device is zoned */ 94 unsigned int zone_nr_conv; /* number of conventional zones */ 95 unsigned int zone_max_open; /* max number of open zones */ 96 unsigned int zone_max_active; /* max number of active zones */ 97 unsigned int submit_queues; /* number of submission queues */ 98 unsigned int prev_submit_queues; /* number of submission queues before change */ 99 unsigned int poll_queues; /* number of IOPOLL submission queues */ 100 unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */ 101 unsigned int home_node; /* home node for the device */ 102 unsigned int queue_mode; /* block interface */ 103 unsigned int blocksize; /* block size */ 104 unsigned int max_sectors; /* Max sectors per command */ 105 unsigned int irqmode; /* IRQ completion handler */ 106 unsigned int hw_queue_depth; /* queue depth */ 107 unsigned int index; /* index of the disk, only valid with a disk */ 108 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */ 109 bool blocking; /* blocking blk-mq device */ 110 bool use_per_node_hctx; /* use per-node allocation for hardware context */ 111 bool power; /* power on/off the device */ 112 bool memory_backed; /* if data is stored in memory */ 113 bool discard; /* if support discard */ 114 bool zoned; /* if device is zoned */ 115 bool virt_boundary; /* virtual boundary on/off for the device */ 116}; 117 118struct nullb { 119 struct nullb_device *dev; 120 struct list_head list; 121 unsigned int index; 122 struct request_queue *q; 123 struct gendisk *disk; 124 struct blk_mq_tag_set *tag_set; 125 struct blk_mq_tag_set __tag_set; 126 unsigned int queue_depth; 127 atomic_long_t cur_bytes; 128 struct hrtimer bw_timer; 129 unsigned long cache_flush_pos; 130 spinlock_t lock; 131 132 struct nullb_queue *queues; 133 unsigned int nr_queues; 134 char disk_name[DISK_NAME_LEN]; 135}; 136 137blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector, 138 sector_t nr_sectors); 139blk_status_t null_process_cmd(struct nullb_cmd *cmd, 140 enum req_opf op, sector_t sector, 141 unsigned int nr_sectors); 142 143#ifdef CONFIG_BLK_DEV_ZONED 144int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q); 145int null_register_zoned_dev(struct nullb *nullb); 146void null_free_zoned_dev(struct nullb_device *dev); 147int null_report_zones(struct gendisk *disk, sector_t sector, 148 unsigned int nr_zones, report_zones_cb cb, void *data); 149blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 150 enum req_opf op, sector_t sector, 151 sector_t nr_sectors); 152size_t null_zone_valid_read_len(struct nullb *nullb, 153 sector_t sector, unsigned int len); 154#else 155static inline int null_init_zoned_dev(struct nullb_device *dev, 156 struct request_queue *q) 157{ 158 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n"); 159 return -EINVAL; 160} 161static inline int null_register_zoned_dev(struct nullb *nullb) 162{ 163 return -ENODEV; 164} 165static inline void null_free_zoned_dev(struct nullb_device *dev) {} 166static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 167 enum req_opf op, sector_t sector, sector_t nr_sectors) 168{ 169 return BLK_STS_NOTSUPP; 170} 171static inline size_t null_zone_valid_read_len(struct nullb *nullb, 172 sector_t sector, 173 unsigned int len) 174{ 175 return len; 176} 177#define null_report_zones NULL 178#endif /* CONFIG_BLK_DEV_ZONED */ 179#endif /* __NULL_BLK_H */