aboutsummaryrefslogtreecommitdiff
path: root/io_uring/rsrc.h
blob: d60c758326b423d6922eae58830c28fc904e2cc3 (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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
// SPDX-License-Identifier: GPL-2.0
#ifndef IOU_RSRC_H
#define IOU_RSRC_H

#include <net/af_unix.h>

#define IO_RSRC_TAG_TABLE_SHIFT	(PAGE_SHIFT - 3)
#define IO_RSRC_TAG_TABLE_MAX	(1U << IO_RSRC_TAG_TABLE_SHIFT)
#define IO_RSRC_TAG_TABLE_MASK	(IO_RSRC_TAG_TABLE_MAX - 1)

enum {
	IORING_RSRC_FILE		= 0,
	IORING_RSRC_BUFFER		= 1,
};

struct io_rsrc_put {
	struct list_head list;
	u64 tag;
	union {
		void *rsrc;
		struct file *file;
		struct io_mapped_ubuf *buf;
	};
};

typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);

struct io_rsrc_data {
	struct io_ring_ctx		*ctx;

	u64				**tags;
	unsigned int			nr;
	rsrc_put_fn			*do_put;
	atomic_t			refs;
	struct completion		done;
	bool				quiesce;
};

struct io_rsrc_node {
	struct percpu_ref		refs;
	struct list_head		node;
	struct list_head		rsrc_list;
	struct io_rsrc_data		*rsrc_data;
	struct llist_node		llist;
	bool				done;
};

struct io_mapped_ubuf {
	u64		ubuf;
	u64		ubuf_end;
	unsigned int	nr_bvecs;
	unsigned long	acct_pages;
	struct bio_vec	bvec[];
};

void io_rsrc_put_work(struct work_struct *work);
void io_rsrc_refs_refill(struct io_ring_ctx *ctx);
void io_wait_rsrc_data(struct io_rsrc_data *data);
void io_rsrc_node_destroy(struct io_rsrc_node *ref_node);
void io_rsrc_refs_drop(struct io_ring_ctx *ctx);
int io_rsrc_node_switch_start(struct io_ring_ctx *ctx);
int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
			  struct io_rsrc_node *node, void *rsrc);
void io_rsrc_node_switch(struct io_ring_ctx *ctx,
			 struct io_rsrc_data *data_to_kill);

int io_import_fixed(int ddir, struct iov_iter *iter,
			   struct io_mapped_ubuf *imu,
			   u64 buf_addr, size_t len);

void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
			    unsigned int nr_args, u64 __user *tags);
void __io_sqe_files_unregister(struct io_ring_ctx *ctx);
int io_sqe_files_unregister(struct io_ring_ctx *ctx);
int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
			  unsigned nr_args, u64 __user *tags);

int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file);

#if defined(CONFIG_UNIX)
static inline bool io_file_need_scm(struct file *filp)
{
	return !!unix_get_socket(filp);
}
#else
static inline bool io_file_need_scm(struct file *filp)
{
	return false;
}
#endif

static inline int io_scm_file_account(struct io_ring_ctx *ctx,
				      struct file *file)
{
	if (likely(!io_file_need_scm(file)))
		return 0;
	return __io_scm_file_account(ctx, file);
}

int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
			     unsigned nr_args);
int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
			    unsigned size, unsigned type);
int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
			unsigned int size, unsigned int type);

static inline void io_rsrc_put_node(struct io_rsrc_node *node, int nr)
{
	percpu_ref_put_many(&node->refs, nr);
}

static inline void io_req_put_rsrc(struct io_kiocb *req)
{
	if (req->rsrc_node)
		io_rsrc_put_node(req->rsrc_node, 1);
}

static inline void io_req_put_rsrc_locked(struct io_kiocb *req,
					  struct io_ring_ctx *ctx)
	__must_hold(&ctx->uring_lock)
{
	struct io_rsrc_node *node = req->rsrc_node;

	if (node) {
		if (node == ctx->rsrc_node)
			ctx->rsrc_cached_refs++;
		else
			io_rsrc_put_node(node, 1);
	}
}

static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx)
{
	ctx->rsrc_cached_refs--;
	if (unlikely(ctx->rsrc_cached_refs < 0))
		io_rsrc_refs_refill(ctx);
}

static inline void io_req_set_rsrc_node(struct io_kiocb *req,
					struct io_ring_ctx *ctx,
					unsigned int issue_flags)
{
	if (!req->rsrc_node) {
		io_ring_submit_lock(ctx, issue_flags);

		lockdep_assert_held(&ctx->uring_lock);

		req->rsrc_node = ctx->rsrc_node;
		io_charge_rsrc_node(ctx);
		io_ring_submit_unlock(ctx, issue_flags);
	}
}

static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
{
	unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
	unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;

	return &data->tags[table_idx][off];
}

int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);

int __io_account_mem(struct user_struct *user, unsigned long nr_pages);

static inline void __io_unaccount_mem(struct user_struct *user,
				      unsigned long nr_pages)
{
	atomic_long_sub(nr_pages, &user->locked_vm);
}

#endif