summaryrefslogtreecommitdiff
path: root/io_uring/uring_cmd.c
blob: 42f63adfa54a04f0b8c67a3babb7415b2bcc96bc (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
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/io_uring/cmd.h>
#include <linux/security.h>
#include <linux/nospec.h>
#include <net/sock.h>

#include <uapi/linux/io_uring.h>
#include <asm/ioctls.h>

#include "io_uring.h"
#include "rsrc.h"
#include "uring_cmd.h"

static void io_uring_cmd_del_cancelable(struct io_uring_cmd *cmd,
		unsigned int issue_flags)
{
	struct io_kiocb *req = cmd_to_io_kiocb(cmd);
	struct io_ring_ctx *ctx = req->ctx;

	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE))
		return;

	cmd->flags &= ~IORING_URING_CMD_CANCELABLE;
	io_ring_submit_lock(ctx, issue_flags);
	hlist_del(&req->hash_node);
	io_ring_submit_unlock(ctx, issue_flags);
}

/*
 * Mark this command as concelable, then io_uring_try_cancel_uring_cmd()
 * will try to cancel this issued command by sending ->uring_cmd() with
 * issue_flags of IO_URING_F_CANCEL.
 *
 * The command is guaranteed to not be done when calling ->uring_cmd()
 * with IO_URING_F_CANCEL, but it is driver's responsibility to deal
 * with race between io_uring canceling and normal completion.
 */
void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
		unsigned int issue_flags)
{
	struct io_kiocb *req = cmd_to_io_kiocb(cmd);
	struct io_ring_ctx *ctx = req->ctx;

	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE)) {
		cmd->flags |= IORING_URING_CMD_CANCELABLE;
		io_ring_submit_lock(ctx, issue_flags);
		hlist_add_head(&req->hash_node, &ctx->cancelable_uring_cmd);
		io_ring_submit_unlock(ctx, issue_flags);
	}
}
EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);

static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
{
	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
	unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;

	ioucmd->task_work_cb(ioucmd, issue_flags);
}

void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned),
			unsigned flags)
{
	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);

	ioucmd->task_work_cb = task_work_cb;
	req->io_task_work.func = io_uring_cmd_work;
	__io_req_task_work_add(req, flags);
}
EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);

static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
					  u64 extra1, u64 extra2)
{
	req->big_cqe.extra1 = extra1;
	req->big_cqe.extra2 = extra2;
}

/*
 * Called by consumers of io_uring_cmd, if they originally returned
 * -EIOCBQUEUED upon receiving the command.
 */
void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
		       unsigned issue_flags)
{
	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);

	io_uring_cmd_del_cancelable(ioucmd, issue_flags);

	if (ret < 0)
		req_set_fail(req);

	io_req_set_res(req, ret, 0);
	if (req->ctx->flags & IORING_SETUP_CQE32)
		io_req_set_cqe32_extra(req, res2, 0);
	if (req->ctx->flags & IORING_SETUP_IOPOLL) {
		/* order with io_iopoll_req_issued() checking ->iopoll_complete */
		smp_store_release(&req->iopoll_completed, 1);
	} else {
		struct io_tw_state ts = {
			.locked = !(issue_flags & IO_URING_F_UNLOCKED),
		};
		io_req_task_complete(req, &ts);
	}
}
EXPORT_SYMBOL_GPL(io_uring_cmd_done);

int io_uring_cmd_prep_async(struct io_kiocb *req)
{
	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);

	memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx));
	ioucmd->sqe = req->async_data;
	return 0;
}

int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);

	if (sqe->__pad1)
		return -EINVAL;

	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
	if (ioucmd->flags & ~IORING_URING_CMD_MASK)
		return -EINVAL;

	if (ioucmd->flags & IORING_URING_CMD_FIXED) {
		struct io_ring_ctx *ctx = req->ctx;
		u16 index;

		req->buf_index = READ_ONCE(sqe->buf_index);
		if (unlikely(req->buf_index >= ctx->nr_user_bufs))
			return -EFAULT;
		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
		req->imu = ctx->user_bufs[index];
		io_req_set_rsrc_node(req, ctx, 0);
	}
	ioucmd->sqe = sqe;
	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
	return 0;
}

int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
{
	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
	struct io_ring_ctx *ctx = req->ctx;
	struct file *file = req->file;
	int ret;

	if (!file->f_op->uring_cmd)
		return -EOPNOTSUPP;

	ret = security_uring_cmd(ioucmd);
	if (ret)
		return ret;

	if (ctx->flags & IORING_SETUP_SQE128)
		issue_flags |= IO_URING_F_SQE128;
	if (ctx->flags & IORING_SETUP_CQE32)
		issue_flags |= IO_URING_F_CQE32;
	if (ctx->compat)
		issue_flags |= IO_URING_F_COMPAT;
	if (ctx->flags & IORING_SETUP_IOPOLL) {
		if (!file->f_op->uring_cmd_iopoll)
			return -EOPNOTSUPP;
		issue_flags |= IO_URING_F_IOPOLL;
		req->iopoll_completed = 0;
	}

	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
	if (ret == -EAGAIN) {
		if (!req_has_async_data(req)) {
			if (io_alloc_async_data(req))
				return -ENOMEM;
			io_uring_cmd_prep_async(req);
		}
		return -EAGAIN;
	}

	if (ret != -EIOCBQUEUED) {
		if (ret < 0)
			req_set_fail(req);
		io_req_set_res(req, ret, 0);
		return ret;
	}

	return IOU_ISSUE_SKIP_COMPLETE;
}

int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
			      struct iov_iter *iter, void *ioucmd)
{
	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);

	return io_import_fixed(rw, iter, req->imu, ubuf, len);
}
EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);

static inline int io_uring_cmd_getsockopt(struct socket *sock,
					  struct io_uring_cmd *cmd,
					  unsigned int issue_flags)
{
	bool compat = !!(issue_flags & IO_URING_F_COMPAT);
	int optlen, optname, level, err;
	void __user *optval;

	level = READ_ONCE(cmd->sqe->level);
	if (level != SOL_SOCKET)
		return -EOPNOTSUPP;

	optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
	optname = READ_ONCE(cmd->sqe->optname);
	optlen = READ_ONCE(cmd->sqe->optlen);

	err = do_sock_getsockopt(sock, compat, level, optname,
				 USER_SOCKPTR(optval),
				 KERNEL_SOCKPTR(&optlen));
	if (err)
		return err;

	/* On success, return optlen */
	return optlen;
}

static inline int io_uring_cmd_setsockopt(struct socket *sock,
					  struct io_uring_cmd *cmd,
					  unsigned int issue_flags)
{
	bool compat = !!(issue_flags & IO_URING_F_COMPAT);
	int optname, optlen, level;
	void __user *optval;
	sockptr_t optval_s;

	optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
	optname = READ_ONCE(cmd->sqe->optname);
	optlen = READ_ONCE(cmd->sqe->optlen);
	level = READ_ONCE(cmd->sqe->level);
	optval_s = USER_SOCKPTR(optval);

	return do_sock_setsockopt(sock, compat, level, optname, optval_s,
				  optlen);
}

#if defined(CONFIG_NET)
int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags)
{
	struct socket *sock = cmd->file->private_data;
	struct sock *sk = sock->sk;
	struct proto *prot = READ_ONCE(sk->sk_prot);
	int ret, arg = 0;

	if (!prot || !prot->ioctl)
		return -EOPNOTSUPP;

	switch (cmd->sqe->cmd_op) {
	case SOCKET_URING_OP_SIOCINQ:
		ret = prot->ioctl(sk, SIOCINQ, &arg);
		if (ret)
			return ret;
		return arg;
	case SOCKET_URING_OP_SIOCOUTQ:
		ret = prot->ioctl(sk, SIOCOUTQ, &arg);
		if (ret)
			return ret;
		return arg;
	case SOCKET_URING_OP_GETSOCKOPT:
		return io_uring_cmd_getsockopt(sock, cmd, issue_flags);
	case SOCKET_URING_OP_SETSOCKOPT:
		return io_uring_cmd_setsockopt(sock, cmd, issue_flags);
	default:
		return -EOPNOTSUPP;
	}
}
EXPORT_SYMBOL_GPL(io_uring_cmd_sock);
#endif