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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
|
/* 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>
#include <linux/spinlock.h>
#include <linux/mutex.h>
struct nullb_cmd {
blk_status_t error;
bool fake_timeout;
struct nullb_queue *nq;
struct hrtimer timer;
};
struct nullb_queue {
struct nullb_device *dev;
unsigned int requeue_selection;
struct list_head poll_list;
spinlock_t poll_lock;
};
struct nullb_zone {
/*
* Zone lock to prevent concurrent modification of a zone write
* pointer position and condition: with memory backing, a write
* command execution may sleep on memory allocation. For this case,
* use mutex as the zone lock. Otherwise, use the spinlock for
* locking the zone.
*/
union {
spinlock_t spinlock;
struct mutex mutex;
};
enum blk_zone_type type;
enum blk_zone_cond cond;
sector_t start;
sector_t wp;
unsigned int len;
unsigned int capacity;
};
struct nullb_device {
struct nullb *nullb;
struct config_group group;
#ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION
struct fault_config timeout_config;
struct fault_config requeue_config;
struct fault_config init_hctx_fault_config;
#endif
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;
unsigned int nr_zones_imp_open;
unsigned int nr_zones_exp_open;
unsigned int nr_zones_closed;
unsigned int imp_close_zone_no;
struct nullb_zone *zones;
sector_t zone_size_sects;
bool need_zone_res_mgmt;
spinlock_t zone_res_lock;
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 zone_max_open; /* max number of open zones */
unsigned int zone_max_active; /* max number of active zones */
unsigned int zone_append_max_sectors; /* Max sectors per zone append command */
unsigned int submit_queues; /* number of submission queues */
unsigned int prev_submit_queues; /* number of submission queues before change */
unsigned int poll_queues; /* number of IOPOLL submission queues */
unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */
unsigned int home_node; /* home node for the device */
unsigned int queue_mode; /* block interface */
unsigned int blocksize; /* block size */
unsigned int max_sectors; /* Max sectors per command */
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 */
bool virt_boundary; /* virtual boundary on/off for the device */
bool no_sched; /* no IO scheduler for the device */
bool shared_tags; /* share tag set between devices for blk-mq */
bool shared_tag_bitmap; /* use hostwide shared tags */
bool fua; /* Support FUA */
};
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;
atomic_long_t cur_bytes;
struct hrtimer bw_timer;
unsigned long cache_flush_pos;
spinlock_t lock;
struct nullb_queue *queues;
char disk_name[DISK_NAME_LEN];
};
blk_status_t null_handle_discard(struct nullb_device *dev, sector_t sector,
sector_t nr_sectors);
blk_status_t null_process_cmd(struct nullb_cmd *cmd, enum req_op op,
sector_t sector, unsigned int nr_sectors);
#ifdef CONFIG_BLK_DEV_ZONED
int null_init_zoned_dev(struct nullb_device *dev, struct queue_limits *lim);
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_op op,
sector_t sector, sector_t nr_sectors);
size_t null_zone_valid_read_len(struct nullb *nullb,
sector_t sector, unsigned int len);
ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
size_t count, enum blk_zone_cond cond);
#else
static inline int null_init_zoned_dev(struct nullb_device *dev,
struct queue_limits *lim)
{
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_op 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;
}
static inline ssize_t zone_cond_store(struct nullb_device *dev,
const char *page, size_t count,
enum blk_zone_cond cond)
{
return -EOPNOTSUPP;
}
#define null_report_zones NULL
#endif /* CONFIG_BLK_DEV_ZONED */
#endif /* __NULL_BLK_H */
|
