1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/errno.h>
4#include <linux/file.h>
5#include <linux/io_uring.h>
6#include <linux/security.h>
7#include <linux/nospec.h>
8
9#include <uapi/linux/io_uring.h>
10#include <uapi/asm-generic/ioctls.h>
11
12#include "io_uring.h"
13#include "rsrc.h"
14#include "uring_cmd.h"
15
16static void io_uring_cmd_del_cancelable(struct io_uring_cmd *cmd,
17 unsigned int issue_flags)
18{
19 struct io_kiocb *req = cmd_to_io_kiocb(cmd);
20 struct io_ring_ctx *ctx = req->ctx;
21
22 if (!(cmd->flags & IORING_URING_CMD_CANCELABLE))
23 return;
24
25 cmd->flags &= ~IORING_URING_CMD_CANCELABLE;
26 io_ring_submit_lock(ctx, issue_flags);
27 hlist_del(n: &req->hash_node);
28 io_ring_submit_unlock(ctx, issue_flags);
29}
30
31/*
32 * Mark this command as concelable, then io_uring_try_cancel_uring_cmd()
33 * will try to cancel this issued command by sending ->uring_cmd() with
34 * issue_flags of IO_URING_F_CANCEL.
35 *
36 * The command is guaranteed to not be done when calling ->uring_cmd()
37 * with IO_URING_F_CANCEL, but it is driver's responsibility to deal
38 * with race between io_uring canceling and normal completion.
39 */
40void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
41 unsigned int issue_flags)
42{
43 struct io_kiocb *req = cmd_to_io_kiocb(cmd);
44 struct io_ring_ctx *ctx = req->ctx;
45
46 if (!(cmd->flags & IORING_URING_CMD_CANCELABLE)) {
47 cmd->flags |= IORING_URING_CMD_CANCELABLE;
48 io_ring_submit_lock(ctx, issue_flags);
49 hlist_add_head(n: &req->hash_node, h: &ctx->cancelable_uring_cmd);
50 io_ring_submit_unlock(ctx, issue_flags);
51 }
52}
53EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);
54
55struct task_struct *io_uring_cmd_get_task(struct io_uring_cmd *cmd)
56{
57 return cmd_to_io_kiocb(cmd)->task;
58}
59EXPORT_SYMBOL_GPL(io_uring_cmd_get_task);
60
61static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
62{
63 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
64 unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
65
66 ioucmd->task_work_cb(ioucmd, issue_flags);
67}
68
69void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
70 void (*task_work_cb)(struct io_uring_cmd *, unsigned),
71 unsigned flags)
72{
73 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
74
75 ioucmd->task_work_cb = task_work_cb;
76 req->io_task_work.func = io_uring_cmd_work;
77 __io_req_task_work_add(req, flags);
78}
79EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);
80
81void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
82 void (*task_work_cb)(struct io_uring_cmd *, unsigned))
83{
84 __io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE);
85}
86EXPORT_SYMBOL_GPL(io_uring_cmd_do_in_task_lazy);
87
88static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
89 u64 extra1, u64 extra2)
90{
91 req->big_cqe.extra1 = extra1;
92 req->big_cqe.extra2 = extra2;
93}
94
95/*
96 * Called by consumers of io_uring_cmd, if they originally returned
97 * -EIOCBQUEUED upon receiving the command.
98 */
99void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
100 unsigned issue_flags)
101{
102 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
103
104 io_uring_cmd_del_cancelable(cmd: ioucmd, issue_flags);
105
106 if (ret < 0)
107 req_set_fail(req);
108
109 io_req_set_res(req, res: ret, cflags: 0);
110 if (req->ctx->flags & IORING_SETUP_CQE32)
111 io_req_set_cqe32_extra(req, extra1: res2, extra2: 0);
112 if (req->ctx->flags & IORING_SETUP_IOPOLL) {
113 /* order with io_iopoll_req_issued() checking ->iopoll_complete */
114 smp_store_release(&req->iopoll_completed, 1);
115 } else {
116 struct io_tw_state ts = {
117 .locked = !(issue_flags & IO_URING_F_UNLOCKED),
118 };
119 io_req_task_complete(req, ts: &ts);
120 }
121}
122EXPORT_SYMBOL_GPL(io_uring_cmd_done);
123
124int io_uring_cmd_prep_async(struct io_kiocb *req)
125{
126 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
127
128 memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx));
129 ioucmd->sqe = req->async_data;
130 return 0;
131}
132
133int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
134{
135 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
136
137 if (sqe->__pad1)
138 return -EINVAL;
139
140 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
141 if (ioucmd->flags & ~IORING_URING_CMD_MASK)
142 return -EINVAL;
143
144 if (ioucmd->flags & IORING_URING_CMD_FIXED) {
145 struct io_ring_ctx *ctx = req->ctx;
146 u16 index;
147
148 req->buf_index = READ_ONCE(sqe->buf_index);
149 if (unlikely(req->buf_index >= ctx->nr_user_bufs))
150 return -EFAULT;
151 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
152 req->imu = ctx->user_bufs[index];
153 io_req_set_rsrc_node(req, ctx, issue_flags: 0);
154 }
155 ioucmd->sqe = sqe;
156 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
157 return 0;
158}
159
160int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
161{
162 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
163 struct io_ring_ctx *ctx = req->ctx;
164 struct file *file = req->file;
165 int ret;
166
167 if (!file->f_op->uring_cmd)
168 return -EOPNOTSUPP;
169
170 ret = security_uring_cmd(ioucmd);
171 if (ret)
172 return ret;
173
174 if (ctx->flags & IORING_SETUP_SQE128)
175 issue_flags |= IO_URING_F_SQE128;
176 if (ctx->flags & IORING_SETUP_CQE32)
177 issue_flags |= IO_URING_F_CQE32;
178 if (ctx->compat)
179 issue_flags |= IO_URING_F_COMPAT;
180 if (ctx->flags & IORING_SETUP_IOPOLL) {
181 if (!file->f_op->uring_cmd_iopoll)
182 return -EOPNOTSUPP;
183 issue_flags |= IO_URING_F_IOPOLL;
184 req->iopoll_completed = 0;
185 WRITE_ONCE(ioucmd->cookie, NULL);
186 }
187
188 ret = file->f_op->uring_cmd(ioucmd, issue_flags);
189 if (ret == -EAGAIN) {
190 if (!req_has_async_data(req)) {
191 if (io_alloc_async_data(req))
192 return -ENOMEM;
193 io_uring_cmd_prep_async(req);
194 }
195 return -EAGAIN;
196 }
197
198 if (ret != -EIOCBQUEUED) {
199 if (ret < 0)
200 req_set_fail(req);
201 io_req_set_res(req, res: ret, cflags: 0);
202 return ret;
203 }
204
205 return IOU_ISSUE_SKIP_COMPLETE;
206}
207
208int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
209 struct iov_iter *iter, void *ioucmd)
210{
211 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
212
213 return io_import_fixed(ddir: rw, iter, imu: req->imu, buf_addr: ubuf, len);
214}
215EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
216
217static inline int io_uring_cmd_getsockopt(struct socket *sock,
218 struct io_uring_cmd *cmd,
219 unsigned int issue_flags)
220{
221 bool compat = !!(issue_flags & IO_URING_F_COMPAT);
222 int optlen, optname, level, err;
223 void __user *optval;
224
225 level = READ_ONCE(cmd->sqe->level);
226 if (level != SOL_SOCKET)
227 return -EOPNOTSUPP;
228
229 optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
230 optname = READ_ONCE(cmd->sqe->optname);
231 optlen = READ_ONCE(cmd->sqe->optlen);
232
233 err = do_sock_getsockopt(sock, compat, level, optname,
234 optval: USER_SOCKPTR(p: optval),
235 optlen: KERNEL_SOCKPTR(p: &optlen));
236 if (err)
237 return err;
238
239 /* On success, return optlen */
240 return optlen;
241}
242
243static inline int io_uring_cmd_setsockopt(struct socket *sock,
244 struct io_uring_cmd *cmd,
245 unsigned int issue_flags)
246{
247 bool compat = !!(issue_flags & IO_URING_F_COMPAT);
248 int optname, optlen, level;
249 void __user *optval;
250 sockptr_t optval_s;
251
252 optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));
253 optname = READ_ONCE(cmd->sqe->optname);
254 optlen = READ_ONCE(cmd->sqe->optlen);
255 level = READ_ONCE(cmd->sqe->level);
256 optval_s = USER_SOCKPTR(p: optval);
257
258 return do_sock_setsockopt(sock, compat, level, optname, optval: optval_s,
259 optlen);
260}
261
262#if defined(CONFIG_NET)
263int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags)
264{
265 struct socket *sock = cmd->file->private_data;
266 struct sock *sk = sock->sk;
267 struct proto *prot = READ_ONCE(sk->sk_prot);
268 int ret, arg = 0;
269
270 if (!prot || !prot->ioctl)
271 return -EOPNOTSUPP;
272
273 switch (cmd->sqe->cmd_op) {
274 case SOCKET_URING_OP_SIOCINQ:
275 ret = prot->ioctl(sk, SIOCINQ, &arg);
276 if (ret)
277 return ret;
278 return arg;
279 case SOCKET_URING_OP_SIOCOUTQ:
280 ret = prot->ioctl(sk, SIOCOUTQ, &arg);
281 if (ret)
282 return ret;
283 return arg;
284 case SOCKET_URING_OP_GETSOCKOPT:
285 return io_uring_cmd_getsockopt(sock, cmd, issue_flags);
286 case SOCKET_URING_OP_SETSOCKOPT:
287 return io_uring_cmd_setsockopt(sock, cmd, issue_flags);
288 default:
289 return -EOPNOTSUPP;
290 }
291}
292EXPORT_SYMBOL_GPL(io_uring_cmd_sock);
293#endif
294

source code of linux/io_uring/uring_cmd.c