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
11 #include "io_uring.h"
12 #include "rsrc.h"
13 #include "uring_cmd.h"
14
io_uring_cmd_work(struct io_kiocb * req,bool * locked)15 static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
16 {
17 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
18
19 ioucmd->task_work_cb(ioucmd);
20 }
21
io_uring_cmd_complete_in_task(struct io_uring_cmd * ioucmd,void (* task_work_cb)(struct io_uring_cmd *))22 void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
23 void (*task_work_cb)(struct io_uring_cmd *))
24 {
25 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
26
27 ioucmd->task_work_cb = task_work_cb;
28 req->io_task_work.func = io_uring_cmd_work;
29 io_req_task_work_add(req);
30 }
31 EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
32
io_req_set_cqe32_extra(struct io_kiocb * req,u64 extra1,u64 extra2)33 static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
34 u64 extra1, u64 extra2)
35 {
36 req->extra1 = extra1;
37 req->extra2 = extra2;
38 req->flags |= REQ_F_CQE32_INIT;
39 }
40
41 /*
42 * Called by consumers of io_uring_cmd, if they originally returned
43 * -EIOCBQUEUED upon receiving the command.
44 */
io_uring_cmd_done(struct io_uring_cmd * ioucmd,ssize_t ret,ssize_t res2)45 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
46 {
47 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
48
49 if (ret < 0)
50 req_set_fail(req);
51
52 io_req_set_res(req, ret, 0);
53 if (req->ctx->flags & IORING_SETUP_CQE32)
54 io_req_set_cqe32_extra(req, res2, 0);
55 if (req->ctx->flags & IORING_SETUP_IOPOLL)
56 /* order with io_iopoll_req_issued() checking ->iopoll_complete */
57 smp_store_release(&req->iopoll_completed, 1);
58 else
59 __io_req_complete(req, 0);
60 }
61 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
62
io_uring_cmd_prep_async(struct io_kiocb * req)63 int io_uring_cmd_prep_async(struct io_kiocb *req)
64 {
65 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
66 size_t cmd_size;
67
68 BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
69 BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);
70
71 cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
72
73 memcpy(req->async_data, ioucmd->cmd, cmd_size);
74 return 0;
75 }
76
io_uring_cmd_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)77 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
78 {
79 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
80
81 if (sqe->__pad1)
82 return -EINVAL;
83
84 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
85 if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
86 return -EINVAL;
87
88 if (ioucmd->flags & IORING_URING_CMD_FIXED) {
89 struct io_ring_ctx *ctx = req->ctx;
90 u16 index;
91
92 req->buf_index = READ_ONCE(sqe->buf_index);
93 if (unlikely(req->buf_index >= ctx->nr_user_bufs))
94 return -EFAULT;
95 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
96 req->imu = ctx->user_bufs[index];
97 io_req_set_rsrc_node(req, ctx, 0);
98 }
99 ioucmd->cmd = sqe->cmd;
100 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
101 return 0;
102 }
103
io_uring_cmd(struct io_kiocb * req,unsigned int issue_flags)104 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
105 {
106 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
107 struct io_ring_ctx *ctx = req->ctx;
108 struct file *file = req->file;
109 int ret;
110
111 if (!req->file->f_op->uring_cmd)
112 return -EOPNOTSUPP;
113
114 ret = security_uring_cmd(ioucmd);
115 if (ret)
116 return ret;
117
118 if (ctx->flags & IORING_SETUP_SQE128)
119 issue_flags |= IO_URING_F_SQE128;
120 if (ctx->flags & IORING_SETUP_CQE32)
121 issue_flags |= IO_URING_F_CQE32;
122 if (ctx->flags & IORING_SETUP_IOPOLL) {
123 issue_flags |= IO_URING_F_IOPOLL;
124 req->iopoll_completed = 0;
125 WRITE_ONCE(ioucmd->cookie, NULL);
126 }
127
128 if (req_has_async_data(req))
129 ioucmd->cmd = req->async_data;
130
131 ret = file->f_op->uring_cmd(ioucmd, issue_flags);
132 if (ret == -EAGAIN) {
133 if (!req_has_async_data(req)) {
134 if (io_alloc_async_data(req))
135 return -ENOMEM;
136 io_uring_cmd_prep_async(req);
137 }
138 return -EAGAIN;
139 }
140
141 if (ret != -EIOCBQUEUED) {
142 if (ret < 0)
143 req_set_fail(req);
144 io_req_set_res(req, ret, 0);
145 return ret;
146 }
147
148 return IOU_ISSUE_SKIP_COMPLETE;
149 }
150
io_uring_cmd_import_fixed(u64 ubuf,unsigned long len,int rw,struct iov_iter * iter,void * ioucmd)151 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
152 struct iov_iter *iter, void *ioucmd)
153 {
154 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
155
156 return io_import_fixed(rw, iter, req->imu, ubuf, len);
157 }
158 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
159
