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 <asm/ioctls.h>
11
12 #include "io_uring.h"
13 #include "rsrc.h"
14 #include "uring_cmd.h"
15
io_uring_cmd_work(struct io_kiocb * req,struct io_tw_state * ts)16 static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
17 {
18 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
19 unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
20
21 ioucmd->task_work_cb(ioucmd, issue_flags);
22 }
23
__io_uring_cmd_do_in_task(struct io_uring_cmd * ioucmd,void (* task_work_cb)(struct io_uring_cmd *,unsigned),unsigned flags)24 void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
25 void (*task_work_cb)(struct io_uring_cmd *, unsigned),
26 unsigned flags)
27 {
28 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
29
30 ioucmd->task_work_cb = task_work_cb;
31 req->io_task_work.func = io_uring_cmd_work;
32 __io_req_task_work_add(req, flags);
33 }
34 EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);
35
io_uring_cmd_do_in_task_lazy(struct io_uring_cmd * ioucmd,void (* task_work_cb)(struct io_uring_cmd *,unsigned))36 void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
37 void (*task_work_cb)(struct io_uring_cmd *, unsigned))
38 {
39 __io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE);
40 }
41 EXPORT_SYMBOL_GPL(io_uring_cmd_do_in_task_lazy);
42
io_req_set_cqe32_extra(struct io_kiocb * req,u64 extra1,u64 extra2)43 static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
44 u64 extra1, u64 extra2)
45 {
46 req->big_cqe.extra1 = extra1;
47 req->big_cqe.extra2 = extra2;
48 }
49
50 /*
51 * Called by consumers of io_uring_cmd, if they originally returned
52 * -EIOCBQUEUED upon receiving the command.
53 */
io_uring_cmd_done(struct io_uring_cmd * ioucmd,ssize_t ret,ssize_t res2,unsigned issue_flags)54 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
55 unsigned issue_flags)
56 {
57 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
58
59 if (ret < 0)
60 req_set_fail(req);
61
62 io_req_set_res(req, ret, 0);
63 if (req->ctx->flags & IORING_SETUP_CQE32)
64 io_req_set_cqe32_extra(req, res2, 0);
65 if (req->ctx->flags & IORING_SETUP_IOPOLL) {
66 /* order with io_iopoll_req_issued() checking ->iopoll_complete */
67 smp_store_release(&req->iopoll_completed, 1);
68 } else {
69 struct io_tw_state ts = {
70 .locked = !(issue_flags & IO_URING_F_UNLOCKED),
71 };
72 io_req_task_complete(req, &ts);
73 }
74 }
75 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
76
io_uring_cmd_prep_async(struct io_kiocb * req)77 int io_uring_cmd_prep_async(struct io_kiocb *req)
78 {
79 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
80
81 memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx));
82 ioucmd->sqe = req->async_data;
83 return 0;
84 }
85
io_uring_cmd_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)86 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
87 {
88 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
89
90 if (sqe->__pad1)
91 return -EINVAL;
92
93 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
94 if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
95 return -EINVAL;
96
97 if (ioucmd->flags & IORING_URING_CMD_FIXED) {
98 struct io_ring_ctx *ctx = req->ctx;
99 u16 index;
100
101 req->buf_index = READ_ONCE(sqe->buf_index);
102 if (unlikely(req->buf_index >= ctx->nr_user_bufs))
103 return -EFAULT;
104 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
105 req->imu = ctx->user_bufs[index];
106 io_req_set_rsrc_node(req, ctx, 0);
107 }
108 ioucmd->sqe = sqe;
109 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
110 return 0;
111 }
112
io_uring_cmd(struct io_kiocb * req,unsigned int issue_flags)113 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
114 {
115 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
116 struct io_ring_ctx *ctx = req->ctx;
117 struct file *file = req->file;
118 int ret;
119
120 if (!file->f_op->uring_cmd)
121 return -EOPNOTSUPP;
122
123 ret = security_uring_cmd(ioucmd);
124 if (ret)
125 return ret;
126
127 if (ctx->flags & IORING_SETUP_SQE128)
128 issue_flags |= IO_URING_F_SQE128;
129 if (ctx->flags & IORING_SETUP_CQE32)
130 issue_flags |= IO_URING_F_CQE32;
131 if (ctx->flags & IORING_SETUP_IOPOLL) {
132 if (!file->f_op->uring_cmd_iopoll)
133 return -EOPNOTSUPP;
134 issue_flags |= IO_URING_F_IOPOLL;
135 req->iopoll_completed = 0;
136 WRITE_ONCE(ioucmd->cookie, NULL);
137 }
138
139 ret = file->f_op->uring_cmd(ioucmd, issue_flags);
140 if (ret == -EAGAIN) {
141 if (!req_has_async_data(req)) {
142 if (io_alloc_async_data(req))
143 return -ENOMEM;
144 io_uring_cmd_prep_async(req);
145 }
146 return -EAGAIN;
147 }
148
149 if (ret != -EIOCBQUEUED) {
150 if (ret < 0)
151 req_set_fail(req);
152 io_req_set_res(req, ret, 0);
153 return ret;
154 }
155
156 return IOU_ISSUE_SKIP_COMPLETE;
157 }
158
io_uring_cmd_import_fixed(u64 ubuf,unsigned long len,int rw,struct iov_iter * iter,void * ioucmd)159 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
160 struct iov_iter *iter, void *ioucmd)
161 {
162 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
163
164 return io_import_fixed(rw, iter, req->imu, ubuf, len);
165 }
166 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
167
io_uring_cmd_sock(struct io_uring_cmd * cmd,unsigned int issue_flags)168 int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags)
169 {
170 struct socket *sock = cmd->file->private_data;
171 struct sock *sk = sock->sk;
172 struct proto *prot = READ_ONCE(sk->sk_prot);
173 int ret, arg = 0;
174
175 if (!prot || !prot->ioctl)
176 return -EOPNOTSUPP;
177
178 switch (cmd->sqe->cmd_op) {
179 case SOCKET_URING_OP_SIOCINQ:
180 ret = prot->ioctl(sk, SIOCINQ, &arg);
181 if (ret)
182 return ret;
183 return arg;
184 case SOCKET_URING_OP_SIOCOUTQ:
185 ret = prot->ioctl(sk, SIOCOUTQ, &arg);
186 if (ret)
187 return ret;
188 return arg;
189 default:
190 return -EOPNOTSUPP;
191 }
192 }
193 EXPORT_SYMBOL_GPL(io_uring_cmd_sock);
194