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 list_head poll_list; 36 spinlock_t poll_lock; 37 38 struct nullb_cmd *cmds; 39 }; 40 41 struct nullb_zone { 42 /* 43 * Zone lock to prevent concurrent modification of a zone write 44 * pointer position and condition: with memory backing, a write 45 * command execution may sleep on memory allocation. For this case, 46 * use mutex as the zone lock. Otherwise, use the spinlock for 47 * locking the zone. 48 */ 49 union { 50 spinlock_t spinlock; 51 struct mutex mutex; 52 }; 53 enum blk_zone_type type; 54 enum blk_zone_cond cond; 55 sector_t start; 56 sector_t wp; 57 unsigned int len; 58 unsigned int capacity; 59 }; 60 61 struct nullb_device { 62 struct nullb *nullb; 63 struct config_item item; 64 struct radix_tree_root data; /* data stored in the disk */ 65 struct radix_tree_root cache; /* disk cache data */ 66 unsigned long flags; /* device flags */ 67 unsigned int curr_cache; 68 struct badblocks badblocks; 69 70 unsigned int nr_zones; 71 unsigned int nr_zones_imp_open; 72 unsigned int nr_zones_exp_open; 73 unsigned int nr_zones_closed; 74 unsigned int imp_close_zone_no; 75 struct nullb_zone *zones; 76 sector_t zone_size_sects; 77 bool need_zone_res_mgmt; 78 spinlock_t zone_res_lock; 79 80 unsigned long size; /* device size in MB */ 81 unsigned long completion_nsec; /* time in ns to complete a request */ 82 unsigned long cache_size; /* disk cache size in MB */ 83 unsigned long zone_size; /* zone size in MB if device is zoned */ 84 unsigned long zone_capacity; /* zone capacity in MB if device is zoned */ 85 unsigned int zone_nr_conv; /* number of conventional zones */ 86 unsigned int zone_max_open; /* max number of open zones */ 87 unsigned int zone_max_active; /* max number of active zones */ 88 unsigned int submit_queues; /* number of submission queues */ 89 unsigned int prev_submit_queues; /* number of submission queues before change */ 90 unsigned int poll_queues; /* number of IOPOLL submission queues */ 91 unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */ 92 unsigned int home_node; /* home node for the device */ 93 unsigned int queue_mode; /* block interface */ 94 unsigned int blocksize; /* block size */ 95 unsigned int max_sectors; /* Max sectors per command */ 96 unsigned int irqmode; /* IRQ completion handler */ 97 unsigned int hw_queue_depth; /* queue depth */ 98 unsigned int index; /* index of the disk, only valid with a disk */ 99 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */ 100 bool blocking; /* blocking blk-mq device */ 101 bool use_per_node_hctx; /* use per-node allocation for hardware context */ 102 bool power; /* power on/off the device */ 103 bool memory_backed; /* if data is stored in memory */ 104 bool discard; /* if support discard */ 105 bool zoned; /* if device is zoned */ 106 bool virt_boundary; /* virtual boundary on/off for the device */ 107 }; 108 109 struct nullb { 110 struct nullb_device *dev; 111 struct list_head list; 112 unsigned int index; 113 struct request_queue *q; 114 struct gendisk *disk; 115 struct blk_mq_tag_set *tag_set; 116 struct blk_mq_tag_set __tag_set; 117 unsigned int queue_depth; 118 atomic_long_t cur_bytes; 119 struct hrtimer bw_timer; 120 unsigned long cache_flush_pos; 121 spinlock_t lock; 122 123 struct nullb_queue *queues; 124 unsigned int nr_queues; 125 char disk_name[DISK_NAME_LEN]; 126 }; 127 128 blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector, 129 sector_t nr_sectors); 130 blk_status_t null_process_cmd(struct nullb_cmd *cmd, 131 enum req_opf op, sector_t sector, 132 unsigned int nr_sectors); 133 134 #ifdef CONFIG_BLK_DEV_ZONED 135 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q); 136 int null_register_zoned_dev(struct nullb *nullb); 137 void null_free_zoned_dev(struct nullb_device *dev); 138 int null_report_zones(struct gendisk *disk, sector_t sector, 139 unsigned int nr_zones, report_zones_cb cb, void *data); 140 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 141 enum req_opf op, sector_t sector, 142 sector_t nr_sectors); 143 size_t null_zone_valid_read_len(struct nullb *nullb, 144 sector_t sector, unsigned int len); 145 #else 146 static inline int null_init_zoned_dev(struct nullb_device *dev, 147 struct request_queue *q) 148 { 149 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n"); 150 return -EINVAL; 151 } 152 static inline int null_register_zoned_dev(struct nullb *nullb) 153 { 154 return -ENODEV; 155 } 156 static inline void null_free_zoned_dev(struct nullb_device *dev) {} 157 static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, 158 enum req_opf op, sector_t sector, sector_t nr_sectors) 159 { 160 return BLK_STS_NOTSUPP; 161 } 162 static inline size_t null_zone_valid_read_len(struct nullb *nullb, 163 sector_t sector, 164 unsigned int len) 165 { 166 return len; 167 } 168 #define null_report_zones NULL 169 #endif /* CONFIG_BLK_DEV_ZONED */ 170 #endif /* __NULL_BLK_H */ 171