1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __BLK_NULL_BLK_H
#define __BLK_NULL_BLK_H
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/hrtimer.h>
#include <linux/configfs.h>
#include <linux/badblocks.h>
#include <linux/fault-inject.h>
struct nullb_cmd {
struct request *rq;
struct bio *bio;
unsigned int tag;
blk_status_t error;
struct nullb_queue *nq;
struct hrtimer timer;
};
struct nullb_queue {
unsigned long *tag_map;
wait_queue_head_t wait;
unsigned int queue_depth;
struct nullb_device *dev;
unsigned int requeue_selection;
struct nullb_cmd *cmds;
};
struct nullb_device {
struct nullb *nullb;
struct config_item item;
struct radix_tree_root data; /* data stored in the disk */
struct radix_tree_root cache; /* disk cache data */
unsigned long flags; /* device flags */
unsigned int curr_cache;
struct badblocks badblocks;
unsigned int nr_zones;
struct blk_zone *zones;
sector_t zone_size_sects;
unsigned long size; /* device size in MB */
unsigned long completion_nsec; /* time in ns to complete a request */
unsigned long cache_size; /* disk cache size in MB */
unsigned long zone_size; /* zone size in MB if device is zoned */
unsigned long zone_capacity; /* zone capacity in MB if device is zoned */
unsigned int zone_nr_conv; /* number of conventional zones */
unsigned int submit_queues; /* number of submission queues */
unsigned int home_node; /* home node for the device */
unsigned int queue_mode; /* block interface */
unsigned int blocksize; /* block size */
unsigned int irqmode; /* IRQ completion handler */
unsigned int hw_queue_depth; /* queue depth */
unsigned int index; /* index of the disk, only valid with a disk */
unsigned int mbps; /* Bandwidth throttle cap (in MB/s) */
bool blocking; /* blocking blk-mq device */
bool use_per_node_hctx; /* use per-node allocation for hardware context */
bool power; /* power on/off the device */
bool memory_backed; /* if data is stored in memory */
bool discard; /* if support discard */
bool zoned; /* if device is zoned */
};
struct nullb {
struct nullb_device *dev;
struct list_head list;
unsigned int index;
struct request_queue *q;
struct gendisk *disk;
struct blk_mq_tag_set *tag_set;
struct blk_mq_tag_set __tag_set;
unsigned int queue_depth;
atomic_long_t cur_bytes;
struct hrtimer bw_timer;
unsigned long cache_flush_pos;
spinlock_t lock;
struct nullb_queue *queues;
unsigned int nr_queues;
char disk_name[DISK_NAME_LEN];
};
blk_status_t null_process_cmd(struct nullb_cmd *cmd,
enum req_opf op, sector_t sector,
unsigned int nr_sectors);
#ifdef CONFIG_BLK_DEV_ZONED
int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q);
int null_register_zoned_dev(struct nullb *nullb);
void null_free_zoned_dev(struct nullb_device *dev);
int null_report_zones(struct gendisk *disk, sector_t sector,
unsigned int nr_zones, report_zones_cb cb, void *data);
blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
enum req_opf op, sector_t sector,
sector_t nr_sectors);
size_t null_zone_valid_read_len(struct nullb *nullb,
sector_t sector, unsigned int len);
#else
static inline int null_init_zoned_dev(struct nullb_device *dev,
struct request_queue *q)
{
pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
return -EINVAL;
}
static inline int null_register_zoned_dev(struct nullb *nullb)
{
return -ENODEV;
}
static inline void null_free_zoned_dev(struct nullb_device *dev) {}
static inline blk_status_t null_process_zoned_cmd(struct nullb_cmd *cmd,
enum req_opf op, sector_t sector, sector_t nr_sectors)
{
return BLK_STS_NOTSUPP;
}
static inline size_t null_zone_valid_read_len(struct nullb *nullb,
sector_t sector,
unsigned int len)
{
return len;
}
#define null_report_zones NULL
#endif /* CONFIG_BLK_DEV_ZONED */
#endif /* __NULL_BLK_H */
|