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