Merge tag 'exfat-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkin...
[platform/kernel/linux-starfive.git] / io_uring / uring_cmd.c
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
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
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
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  */
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_post(req, 0);
60 }
61 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
62
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
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
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
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);