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 bool virt_boundary; /* virtual boundary on/off for the device */ 101 }; 102 103 struct nullb { 104 struct nullb_device *dev; 105 struct list_head list; 106 unsigned int index; 107 struct request_queue *q; 108 struct gendisk *disk; 109 struct blk_mq_tag_set *tag_set; 110 struct blk_mq_tag_set __tag_set; 111 unsigned int queue_depth; 112 atomic_long_t cur_bytes; 113 struct hrtimer bw_timer; 114 unsigned long cache_flush_pos; 115 spinlock_t lock; 116 117 struct nullb_queue *queues; 118 unsigned int nr_queues; 119 char disk_name[DISK_NAME_LEN]; 120 }; 121 122 blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector, 123 sector_t nr_sectors); 124 blk_status_t null_process_cmd(struct nullb_cmd *cmd, 125 enum req_opf op, sector_t sector, 126 unsigned int nr_sectors); 127 128 #ifdef CONFIG_BLK_DEV_ZONED 129 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q); 130 int null_register_zoned_dev(struct nullb *nullb); 131 void null_free_zoned_dev(struct nullb_device *dev); 132 int null_report_zones(struct gendisk *disk, sector_t sector, 133 unsigned int nr_zones, report_zones_cb cb, void *data); 134 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 135 enum req_opf op, sector_t sector, 136 sector_t nr_sectors); 137 size_t null_zone_valid_read_len(struct nullb *nullb, 138 sector_t sector, unsigned int len); 139 #else 140 static inline int null_init_zoned_dev(struct nullb_device *dev, 141 struct request_queue *q) 142 { 143 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n"); 144 return -EINVAL; 145 } 146 static inline int null_register_zoned_dev(struct nullb *nullb) 147 { 148 return -ENODEV; 149 } 150 static inline void null_free_zoned_dev(struct nullb_device *dev) {} 151 static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 152 enum req_opf op, sector_t sector, sector_t nr_sectors) 153 { 154 return BLK_STS_NOTSUPP; 155 } 156 static inline size_t null_zone_valid_read_len(struct nullb *nullb, 157 sector_t sector, 158 unsigned int len) 159 { 160 return len; 161 } 162 #define null_report_zones NULL 163 #endif /* CONFIG_BLK_DEV_ZONED */ 164 #endif /* __NULL_BLK_H */ 165