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 blk_status_t error; 20 bool fake_timeout; 21 struct nullb_queue *nq; 22 struct hrtimer timer; 23 }; 24 25 struct nullb_queue { 26 struct nullb_device *dev; 27 unsigned int requeue_selection; 28 29 struct list_head poll_list; 30 spinlock_t poll_lock; 31 }; 32 33 struct nullb_zone { 34 /* 35 * Zone lock to prevent concurrent modification of a zone write 36 * pointer position and condition: with memory backing, a write 37 * command execution may sleep on memory allocation. For this case, 38 * use mutex as the zone lock. Otherwise, use the spinlock for 39 * locking the zone. 40 */ 41 union { 42 spinlock_t spinlock; 43 struct mutex mutex; 44 }; 45 enum blk_zone_type type; 46 enum blk_zone_cond cond; 47 sector_t start; 48 sector_t wp; 49 unsigned int len; 50 unsigned int capacity; 51 }; 52 53 struct nullb_device { 54 struct nullb *nullb; 55 struct config_group group; 56 #ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION 57 struct fault_config timeout_config; 58 struct fault_config requeue_config; 59 struct fault_config init_hctx_fault_config; 60 #endif 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 zone_append_max_sectors; /* Max sectors per zone append command */ 86 unsigned int submit_queues; /* number of submission queues */ 87 unsigned int prev_submit_queues; /* number of submission queues before change */ 88 unsigned int poll_queues; /* number of IOPOLL submission queues */ 89 unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */ 90 unsigned int home_node; /* home node for the device */ 91 unsigned int queue_mode; /* block interface */ 92 unsigned int blocksize; /* block size */ 93 unsigned int max_sectors; /* Max sectors per command */ 94 unsigned int irqmode; /* IRQ completion handler */ 95 unsigned int hw_queue_depth; /* queue depth */ 96 unsigned int index; /* index of the disk, only valid with a disk */ 97 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */ 98 bool blocking; /* blocking blk-mq device */ 99 bool use_per_node_hctx; /* use per-node allocation for hardware context */ 100 bool power; /* power on/off the device */ 101 bool memory_backed; /* if data is stored in memory */ 102 bool discard; /* if support discard */ 103 bool zoned; /* if device is zoned */ 104 bool zone_full; /* Initialize zones to be full */ 105 bool virt_boundary; /* virtual boundary on/off for the device */ 106 bool no_sched; /* no IO scheduler for the device */ 107 bool shared_tags; /* share tag set between devices for blk-mq */ 108 bool shared_tag_bitmap; /* use hostwide shared tags */ 109 bool fua; /* Support FUA */ 110 bool rotational; /* Fake rotational device */ 111 }; 112 113 struct nullb { 114 struct nullb_device *dev; 115 struct list_head list; 116 unsigned int index; 117 struct request_queue *q; 118 struct gendisk *disk; 119 struct blk_mq_tag_set *tag_set; 120 struct blk_mq_tag_set __tag_set; 121 atomic_long_t cur_bytes; 122 struct hrtimer bw_timer; 123 unsigned long cache_flush_pos; 124 spinlock_t lock; 125 126 struct nullb_queue *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, enum req_op op, 133 sector_t sector, unsigned int nr_sectors); 134 135 #ifdef CONFIG_BLK_DEV_ZONED 136 int null_init_zoned_dev(struct nullb_device *dev, struct queue_limits *lim); 137 int null_register_zoned_dev(struct nullb *nullb); 138 void null_free_zoned_dev(struct nullb_device *dev); 139 int null_report_zones(struct gendisk *disk, sector_t sector, 140 unsigned int nr_zones, report_zones_cb cb, void *data); 141 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd, enum req_op op, 142 sector_t sector, sector_t nr_sectors); 143 size_t null_zone_valid_read_len(struct nullb *nullb, 144 sector_t sector, unsigned int len); 145 ssize_t zone_cond_store(struct nullb_device *dev, const char *page, 146 size_t count, enum blk_zone_cond cond); 147 #else 148 static inline int null_init_zoned_dev(struct nullb_device *dev, 149 struct queue_limits *lim) 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_op 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 static inline ssize_t zone_cond_store(struct nullb_device *dev, 171 const char *page, size_t count, 172 enum blk_zone_cond cond) 173 { 174 return -EOPNOTSUPP; 175 } 176 #define null_report_zones NULL 177 #endif /* CONFIG_BLK_DEV_ZONED */ 178 #endif /* __NULL_BLK_H */ 179