summaryrefslogtreecommitdiff
path: root/fs/io-wq.h
blob: 42f0be64a84d57a2087ce194e4116e4674eeab2c (plain)
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
#ifndef INTERNAL_IO_WQ_H
#define INTERNAL_IO_WQ_H

#include <linux/refcount.h>
#include <linux/io_uring.h>

struct io_wq;

enum {
	IO_WQ_WORK_CANCEL	= 1,
	IO_WQ_WORK_HASHED	= 2,
	IO_WQ_WORK_UNBOUND	= 4,
	IO_WQ_WORK_CONCURRENT	= 16,

	IO_WQ_HASH_SHIFT	= 24,	/* upper 8 bits are used for hash key */
};

enum io_wq_cancel {
	IO_WQ_CANCEL_OK,	/* cancelled before started */
	IO_WQ_CANCEL_RUNNING,	/* found, running, and attempted cancelled */
	IO_WQ_CANCEL_NOTFOUND,	/* work not found */
};

static inline void wq_list_add_after(struct io_wq_work_node *node,
				     struct io_wq_work_node *pos,
				     struct io_wq_work_list *list)
{
	struct io_wq_work_node *next = pos->next;

	pos->next = node;
	node->next = next;
	if (!next)
		list->last = node;
}

static inline void wq_list_add_tail(struct io_wq_work_node *node,
				    struct io_wq_work_list *list)
{
	if (!list->first) {
		list->last = node;
		WRITE_ONCE(list->first, node);
	} else {
		list->last->next = node;
		list->last = node;
	}
	node->next = NULL;
}

static inline void wq_list_cut(struct io_wq_work_list *list,
			       struct io_wq_work_node *last,
			       struct io_wq_work_node *prev)
{
	/* first in the list, if prev==NULL */
	if (!prev)
		WRITE_ONCE(list->first, last->next);
	else
		prev->next = last->next;

	if (last == list->last)
		list->last = prev;
	last->next = NULL;
}

static inline void wq_list_del(struct io_wq_work_list *list,
			       struct io_wq_work_node *node,
			       struct io_wq_work_node *prev)
{
	wq_list_cut(list, node, prev);
}

#define wq_list_for_each(pos, prv, head)			\
	for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next)

#define wq_list_empty(list)	(READ_ONCE((list)->first) == NULL)
#define INIT_WQ_LIST(list)	do {				\
	(list)->first = NULL;					\
	(list)->last = NULL;					\
} while (0)

struct io_wq_work {
	struct io_wq_work_node list;
	unsigned flags;
	unsigned short personality;
};

static inline struct io_wq_work *wq_next_work(struct io_wq_work *work)
{
	if (!work->list.next)
		return NULL;

	return container_of(work->list.next, struct io_wq_work, list);
}

typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *);
typedef void (io_wq_work_fn)(struct io_wq_work *);

struct io_wq_hash {
	refcount_t refs;
	unsigned long map;
	struct wait_queue_head wait;
};

static inline void io_wq_put_hash(struct io_wq_hash *hash)
{
	if (refcount_dec_and_test(&hash->refs))
		kfree(hash);
}

struct io_wq_data {
	struct io_wq_hash *hash;
	io_wq_work_fn *do_work;
	free_work_fn *free_work;
};

struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data);
void io_wq_put(struct io_wq *wq);
void io_wq_put_and_exit(struct io_wq *wq);

void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work);
void io_wq_hash_work(struct io_wq_work *work, void *val);

pid_t io_wq_fork_thread(int (*fn)(void *), void *arg);

static inline bool io_wq_is_hashed(struct io_wq_work *work)
{
	return work->flags & IO_WQ_WORK_HASHED;
}

typedef bool (work_cancel_fn)(struct io_wq_work *, void *);

enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
					void *data, bool cancel_all);

#if defined(CONFIG_IO_WQ)
extern void io_wq_worker_sleeping(struct task_struct *);
extern void io_wq_worker_running(struct task_struct *);
#else
static inline void io_wq_worker_sleeping(struct task_struct *tsk)
{
}
static inline void io_wq_worker_running(struct task_struct *tsk)
{
}
#endif

static inline bool io_wq_current_is_worker(void)
{
	return in_task() && (current->flags & PF_IO_WORKER) &&
		current->pf_io_worker;
}
#endif