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
16 struct nullb_cmd {
17 struct request *rq;
18 struct bio *bio;
19 unsigned int tag;
20 blk_status_t error;
21 struct nullb_queue *nq;
22 struct hrtimer timer;
23 };
24
25 struct nullb_queue {
26 unsigned long *tag_map;
27 wait_queue_head_t wait;
28 unsigned int queue_depth;
29 struct nullb_device *dev;
30 unsigned int requeue_selection;
31
32 struct nullb_cmd *cmds;
33 };
34
35 struct nullb_device {
36 struct nullb *nullb;
37 struct config_item item;
38 struct radix_tree_root data; /* data stored in the disk */
39 struct radix_tree_root cache; /* disk cache data */
40 unsigned long flags; /* device flags */
41 unsigned int curr_cache;
42 struct badblocks badblocks;
43
44 unsigned int nr_zones;
45 unsigned int nr_zones_imp_open;
46 unsigned int nr_zones_exp_open;
47 unsigned int nr_zones_closed;
48 struct blk_zone *zones;
49 sector_t zone_size_sects;
50 spinlock_t zone_lock;
51 unsigned long *zone_locks;
52
53 unsigned long size; /* device size in MB */
54 unsigned long completion_nsec; /* time in ns to complete a request */
55 unsigned long cache_size; /* disk cache size in MB */
56 unsigned long zone_size; /* zone size in MB if device is zoned */
57 unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
58 unsigned int zone_nr_conv; /* number of conventional zones */
59 unsigned int zone_max_open; /* max number of open zones */
60 unsigned int zone_max_active; /* max number of active zones */
61 unsigned int submit_queues; /* number of submission queues */
62 unsigned int home_node; /* home node for the device */
63 unsigned int queue_mode; /* block interface */
64 unsigned int blocksize; /* block size */
65 unsigned int irqmode; /* IRQ completion handler */
66 unsigned int hw_queue_depth; /* queue depth */
67 unsigned int index; /* index of the disk, only valid with a disk */
68 unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
69 bool blocking; /* blocking blk-mq device */
70 bool use_per_node_hctx; /* use per-node allocation for hardware context */
71 bool power; /* power on/off the device */
72 bool memory_backed; /* if data is stored in memory */
73 bool discard; /* if support discard */
74 bool zoned; /* if device is zoned */
75 };
76
77 struct nullb {
78 struct nullb_device *dev;
79 struct list_head list;
80 unsigned int index;
81 struct request_queue *q;
82 struct gendisk *disk;
83 struct blk_mq_tag_set *tag_set;
84 struct blk_mq_tag_set __tag_set;
85 unsigned int queue_depth;
86 atomic_long_t cur_bytes;
87 struct hrtimer bw_timer;
88 unsigned long cache_flush_pos;
89 spinlock_t lock;
90
91 struct nullb_queue *queues;
92 unsigned int nr_queues;
93 char disk_name[DISK_NAME_LEN];
94 };
95
96 blk_status_t null_process_cmd(struct nullb_cmd *cmd,
97 enum req_opf op, sector_t sector,
98 unsigned int nr_sectors);
99
100 #ifdef CONFIG_BLK_DEV_ZONED
101 int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q);
102 int null_register_zoned_dev(struct nullb *nullb);
103 void null_free_zoned_dev(struct nullb_device *dev);
104 int null_report_zones(struct gendisk *disk, sector_t sector,
105 unsigned int nr_zones, report_zones_cb cb, void *data);
106 blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
107 enum req_opf op, sector_t sector,
108 sector_t nr_sectors);
109 size_t null_zone_valid_read_len(struct nullb *nullb,
110 sector_t sector, unsigned int len);
111 #else
null_init_zoned_dev(struct nullb_device * dev,struct request_queue * q)112 static inline int null_init_zoned_dev(struct nullb_device *dev,
113 struct request_queue *q)
114 {
115 pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
116 return -EINVAL;
117 }
null_register_zoned_dev(struct nullb * nullb)118 static inline int null_register_zoned_dev(struct nullb *nullb)
119 {
120 return -ENODEV;
121 }
null_free_zoned_dev(struct nullb_device * dev)122 static inline void null_free_zoned_dev(struct nullb_device *dev) {}
null_process_zoned_cmd(struct nullb_cmd * cmd,enum req_opf op,sector_t sector,sector_t nr_sectors)123 static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
124 enum req_opf op, sector_t sector, sector_t nr_sectors)
125 {
126 return BLK_STS_NOTSUPP;
127 }
null_zone_valid_read_len(struct nullb * nullb,sector_t sector,unsigned int len)128 static inline size_t null_zone_valid_read_len(struct nullb *nullb,
129 sector_t sector,
130 unsigned int len)
131 {
132 return len;
133 }
134 #define null_report_zones NULL
135 #endif /* CONFIG_BLK_DEV_ZONED */
136 #endif /* __NULL_BLK_H */
137
