xref: /linux/include/linux/io_uring/cmd.h (revision 0048fbb4011ec55c32d3148b2cda56433f273375)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _LINUX_IO_URING_CMD_H
3 #define _LINUX_IO_URING_CMD_H
4 
5 #include <uapi/linux/io_uring.h>
6 #include <linux/io_uring_types.h>
7 #include <linux/blk-mq.h>
8 
9 /* only top 8 bits of sqe->uring_cmd_flags for kernel internal use */
10 #define IORING_URING_CMD_CANCELABLE	(1U << 30)
11 /* io_uring_cmd is being issued again */
12 #define IORING_URING_CMD_REISSUE	(1U << 31)
13 
14 struct io_uring_cmd {
15 	struct file	*file;
16 	const struct io_uring_sqe *sqe;
17 	u32		cmd_op;
18 	u32		flags;
19 	u8		pdu[32]; /* available inline for free use */
20 	u8		unused[8];
21 };
22 
23 static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe)
24 {
25 	return sqe->cmd;
26 }
27 
28 static inline void io_uring_cmd_private_sz_check(size_t cmd_sz)
29 {
30 	BUILD_BUG_ON(cmd_sz > sizeof_field(struct io_uring_cmd, pdu));
31 }
32 #define io_uring_cmd_to_pdu(cmd, pdu_type) ( \
33 	io_uring_cmd_private_sz_check(sizeof(pdu_type)), \
34 	((pdu_type *)&(cmd)->pdu) \
35 )
36 
37 #if defined(CONFIG_IO_URING)
38 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
39 			      struct iov_iter *iter,
40 			      struct io_uring_cmd *ioucmd,
41 			      unsigned int issue_flags);
42 int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
43 				  const struct iovec __user *uvec,
44 				  size_t uvec_segs,
45 				  int ddir, struct iov_iter *iter,
46 				  unsigned issue_flags);
47 
48 /*
49  * Completes the request, i.e. posts an io_uring CQE and deallocates @ioucmd
50  * and the corresponding io_uring request.
51  *
52  * Note: the caller should never hard code @issue_flags and is only allowed
53  * to pass the mask provided by the core io_uring code.
54  */
55 void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret, u64 res2,
56 			 unsigned issue_flags, bool is_cqe32);
57 
58 void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
59 			    io_req_tw_func_t task_work_cb,
60 			    unsigned flags);
61 
62 /*
63  * Note: the caller should never hard code @issue_flags and only use the
64  * mask provided by the core io_uring code.
65  */
66 void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
67 		unsigned int issue_flags);
68 
69 /* Execute the request from a blocking context */
70 void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd);
71 
72 /*
73  * Select a buffer from the provided buffer group for multishot uring_cmd.
74  * Returns the selected buffer address and size.
75  */
76 struct io_br_sel io_uring_cmd_buffer_select(struct io_uring_cmd *ioucmd,
77 					    unsigned buf_group, size_t *len,
78 					    unsigned int issue_flags);
79 
80 /*
81  * Complete a multishot uring_cmd event. This will post a CQE to the completion
82  * queue and update the provided buffer.
83  */
84 bool io_uring_mshot_cmd_post_cqe(struct io_uring_cmd *ioucmd,
85 				 struct io_br_sel *sel, unsigned int issue_flags);
86 
87 #else
88 static inline int
89 io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
90 			  struct iov_iter *iter, struct io_uring_cmd *ioucmd,
91 			  unsigned int issue_flags)
92 {
93 	return -EOPNOTSUPP;
94 }
95 static inline int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
96 						const struct iovec __user *uvec,
97 						size_t uvec_segs,
98 						int ddir, struct iov_iter *iter,
99 						unsigned issue_flags)
100 {
101 	return -EOPNOTSUPP;
102 }
103 static inline void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret,
104 		u64 ret2, unsigned issue_flags, bool is_cqe32)
105 {
106 }
107 static inline void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
108 			    io_req_tw_func_t task_work_cb, unsigned flags)
109 {
110 }
111 static inline void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
112 		unsigned int issue_flags)
113 {
114 }
115 static inline void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd)
116 {
117 }
118 static inline struct io_br_sel
119 io_uring_cmd_buffer_select(struct io_uring_cmd *ioucmd, unsigned buf_group,
120 			   size_t *len, unsigned int issue_flags)
121 {
122 	return (struct io_br_sel) { .val = -EOPNOTSUPP };
123 }
124 static inline bool io_uring_mshot_cmd_post_cqe(struct io_uring_cmd *ioucmd,
125 				struct io_br_sel *sel, unsigned int issue_flags)
126 {
127 	return true;
128 }
129 #endif
130 
131 static inline struct io_uring_cmd *io_uring_cmd_from_tw(struct io_tw_req tw_req)
132 {
133 	return io_kiocb_to_cmd(tw_req.req, struct io_uring_cmd);
134 }
135 
136 /* task_work executor checks the deferred list completion */
137 #define IO_URING_CMD_TASK_WORK_ISSUE_FLAGS IO_URING_F_COMPLETE_DEFER
138 
139 /* users must follow the IOU_F_TWQ_LAZY_WAKE semantics */
140 static inline void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
141 			io_req_tw_func_t task_work_cb)
142 {
143 	__io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE);
144 }
145 
146 static inline void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
147 			io_req_tw_func_t task_work_cb)
148 {
149 	__io_uring_cmd_do_in_task(ioucmd, task_work_cb, 0);
150 }
151 
152 static inline struct task_struct *io_uring_cmd_get_task(struct io_uring_cmd *cmd)
153 {
154 	return cmd_to_io_kiocb(cmd)->tctx->task;
155 }
156 
157 /*
158  * Return uring_cmd's context reference as its context handle for driver to
159  * track per-context resource, such as registered kernel IO buffer
160  */
161 static inline void *io_uring_cmd_ctx_handle(struct io_uring_cmd *cmd)
162 {
163 	return cmd_to_io_kiocb(cmd)->ctx;
164 }
165 
166 static inline void io_uring_cmd_done(struct io_uring_cmd *ioucmd, s32 ret,
167 				     unsigned issue_flags)
168 {
169 	return __io_uring_cmd_done(ioucmd, ret, 0, issue_flags, false);
170 }
171 
172 static inline void io_uring_cmd_done32(struct io_uring_cmd *ioucmd, s32 ret,
173 				       u64 res2, unsigned issue_flags)
174 {
175 	return __io_uring_cmd_done(ioucmd, ret, res2, issue_flags, true);
176 }
177 
178 int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,
179 			    void (*release)(void *), unsigned int index,
180 			    unsigned int issue_flags);
181 int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,
182 			      unsigned int issue_flags);
183 
184 #endif /* _LINUX_IO_URING_CMD_H */
185