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 18 struct nullb_cmd { 19 struct request *rq; 20 struct bio *bio; 21 unsigned int tag; 22 blk_status_t error; 23 struct nullb_queue *nq; 24 struct hrtimer timer; 25 bool fake_timeout; 26 }; 27 28 struct nullb_queue { 29 unsigned long *tag_map; 30 wait_queue_head_t wait; 31 unsigned int queue_depth; 32 struct nullb_device *dev; 33 unsigned int requeue_selection; 34 35 struct nullb_cmd *cmds; 36 }; 37 38 struct nullb_zone { 39 /* 40 * Zone lock to prevent concurrent modification of a zone write 41 * pointer position and condition: with memory backing, a write 42 * command execution may sleep on memory allocation. For this case, 43 * use mutex as the zone lock. Otherwise, use the spinlock for 44 * locking the zone. 45 */ 46 union { 47 spinlock_t spinlock; 48 struct mutex mutex; 49 }; 50 enum blk_zone_type type; 51 enum blk_zone_cond cond; 52 sector_t start; 53 sector_t wp; 54 unsigned int len; 55 unsigned int capacity; 56 }; 57 58 struct nullb_device { 59 struct nullb *nullb; 60 struct config_item item; 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 67 unsigned int nr_zones; 68 unsigned int nr_zones_imp_open; 69 unsigned int nr_zones_exp_open; 70 unsigned int nr_zones_closed; 71 unsigned int imp_close_zone_no; 72 struct nullb_zone *zones; 73 sector_t zone_size_sects; 74 bool need_zone_res_mgmt; 75 spinlock_t zone_res_lock; 76 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 */ 80 unsigned long zone_size; /* zone size in MB if device is zoned */ 81 unsigned long zone_capacity; /* zone capacity in MB if device is zoned */ 82 unsigned int zone_nr_conv; /* number of conventional zones */ 83 unsigned int zone_max_open; /* max number of open zones */ 84 unsigned int zone_max_active; /* max number of active zones */ 85 unsigned int submit_queues; /* number of submission queues */ 86 unsigned int home_node; /* home node for the device */ 87 unsigned int queue_mode; /* block interface */ 88 unsigned int blocksize; /* block size */ 89 unsigned int max_sectors; /* Max sectors per command */ 90 unsigned int irqmode; /* IRQ completion handler */ 91 unsigned int hw_queue_depth; /* queue depth */ 92 unsigned int index; /* index of the disk, only valid with a disk */ 93 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */ 94 bool blocking; /* blocking blk-mq device */ 95 bool use_per_node_hctx; /* use per-node allocation for hardware context */ 96 bool power; /* power on/off the device */ 97 bool memory_backed; /* if data is stored in memory */ 98 bool discard; /* if support discard */ 99 bool zoned; /* if device is zoned */ 100 }; 101 102 struct nullb { 103 struct nullb_device *dev; 104 struct list_head list; 105 unsigned int index; 106 struct request_queue *q; 107 struct gendisk *disk; 108 struct blk_mq_tag_set *tag_set; 109 struct blk_mq_tag_set __tag_set; 110 unsigned int queue_depth; 111 atomic_long_t cur_bytes; 112 struct hrtimer bw_timer; 113 unsigned long cache_flush_pos; 114 spinlock_t lock; 115 116 struct nullb_queue *queues; 117 unsigned int nr_queues; 118 char disk_name[DISK_NAME_LEN]; 119 }; 120 121 blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector, 122 sector_t nr_sectors); 123 blk_status_t null_process_cmd(struct nullb_cmd *cmd, 124 enum req_opf op, sector_t sector, 125 unsigned int nr_sectors); 126 127 #ifdef CONFIG_BLK_DEV_ZONED 128 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q); 129 int null_register_zoned_dev(struct nullb *nullb); 130 void null_free_zoned_dev(struct nullb_device *dev); 131 int null_report_zones(struct gendisk *disk, sector_t sector, 132 unsigned int nr_zones, report_zones_cb cb, void *data); 133 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 134 enum req_opf op, sector_t sector, 135 sector_t nr_sectors); 136 size_t null_zone_valid_read_len(struct nullb *nullb, 137 sector_t sector, unsigned int len); 138 #else 139 static inline int null_init_zoned_dev(struct nullb_device *dev, 140 struct request_queue *q) 141 { 142 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n"); 143 return -EINVAL; 144 } 145 static inline int null_register_zoned_dev(struct nullb *nullb) 146 { 147 return -ENODEV; 148 } 149 static inline void null_free_zoned_dev(struct nullb_device *dev) {} 150 static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 151 enum req_opf op, sector_t sector, sector_t nr_sectors) 152 { 153 return BLK_STS_NOTSUPP; 154 } 155 static inline size_t null_zone_valid_read_len(struct nullb *nullb, 156 sector_t sector, 157 unsigned int len) 158 { 159 return len; 160 } 161 #define null_report_zones NULL 162 #endif /* CONFIG_BLK_DEV_ZONED */ 163 #endif /* __NULL_BLK_H */ 164