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