blob: 40ceba1fe8be28d77ccf82af75a3f0e0eac09499 (
plain) (
blame)
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
|
/*
* Internal header file _only_ for device mapper core
*
* Copyright (C) 2016 Red Hat, Inc. All rights reserved.
*
* This file is released under the LGPL.
*/
#ifndef DM_CORE_INTERNAL_H
#define DM_CORE_INTERNAL_H
#include <linux/kthread.h>
#include <linux/ktime.h>
#include <linux/blk-mq.h>
#include <trace/events/block.h>
#include "dm.h"
#define DM_RESERVED_MAX_IOS 1024
struct dm_kobject_holder {
struct kobject kobj;
struct completion completion;
};
/*
* DM core internal structure that used directly by dm.c and dm-rq.c
* DM targets must _not_ deference a mapped_device to directly access its members!
*/
struct mapped_device {
struct srcu_struct io_barrier;
struct mutex suspend_lock;
/*
* The current mapping (struct dm_table *).
* Use dm_get_live_table{_fast} or take suspend_lock for
* dereference.
*/
void __rcu *map;
struct list_head table_devices;
struct mutex table_devices_lock;
unsigned long flags;
struct request_queue *queue;
int numa_node_id;
unsigned type;
/* Protect queue and type against concurrent access. */
struct mutex type_lock;
atomic_t holders;
atomic_t open_count;
struct dm_target *immutable_target;
struct target_type *immutable_target_type;
struct gendisk *disk;
char name[16];
void *interface_ptr;
/*
* A list of ios that arrived while we were suspended.
*/
atomic_t pending[2];
wait_queue_head_t wait;
struct work_struct work;
spinlock_t deferred_lock;
struct bio_list deferred;
/*
* Event handling.
*/
wait_queue_head_t eventq;
atomic_t event_nr;
atomic_t uevent_seq;
struct list_head uevent_list;
spinlock_t uevent_lock; /* Protect access to uevent_list */
/* the number of internal suspends */
unsigned internal_suspend_count;
/*
* Processing queue (flush)
*/
struct workqueue_struct *wq;
/*
* io objects are allocated from here.
*/
mempool_t *io_pool;
mempool_t *rq_pool;
struct bio_set *bs;
/*
* freeze/thaw support require holding onto a super block
*/
struct super_block *frozen_sb;
/* forced geometry settings */
struct hd_geometry geometry;
struct block_device *bdev;
/* kobject and completion */
struct dm_kobject_holder kobj_holder;
/* zero-length flush that will be cloned and submitted to targets */
struct bio flush_bio;
struct dm_stats stats;
struct kthread_worker kworker;
struct task_struct *kworker_task;
/* for request-based merge heuristic in dm_request_fn() */
unsigned seq_rq_merge_deadline_usecs;
int last_rq_rw;
sector_t last_rq_pos;
ktime_t last_rq_start_time;
/* for blk-mq request-based DM support */
struct blk_mq_tag_set *tag_set;
bool use_blk_mq:1;
bool init_tio_pdu:1;
};
void dm_init_md_queue(struct mapped_device *md);
void dm_init_normal_md_queue(struct mapped_device *md);
int md_in_flight(struct mapped_device *md);
void disable_write_same(struct mapped_device *md);
static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
{
return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
}
unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max);
static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
{
return !maxlen || strlen(result) + 1 >= maxlen;
}
#endif
|