cmd.h

  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
 14struct 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
 23static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe)
 24{
 25	return sqe->cmd;
 26}
 27
 28static 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)
 38int 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);
 42int 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 */
 55void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret, u64 res2,
 56			 unsigned issue_flags, bool is_cqe32);
 57
 58void __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 */
 66void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
 67		unsigned int issue_flags);
 68
 69/* Execute the request from a blocking context */
 70void 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 */
 76struct 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 */
 84bool io_uring_mshot_cmd_post_cqe(struct io_uring_cmd *ioucmd,
 85				 struct io_br_sel *sel, unsigned int issue_flags);
 86
 87#else
 88static inline int
 89io_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}
 95static 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}
103static inline void __io_uring_cmd_done(struct io_uring_cmd *cmd, s32 ret,
104		u64 ret2, unsigned issue_flags, bool is_cqe32)
105{
106}
107static 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}
111static inline void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
112		unsigned int issue_flags)
113{
114}
115static inline void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd)
116{
117}
118static inline struct io_br_sel
119io_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}
124static 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
131static 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 */
140static 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
146static 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
152static 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 */
161static inline void *io_uring_cmd_ctx_handle(struct io_uring_cmd *cmd)
162{
163	return cmd_to_io_kiocb(cmd)->ctx;
164}
165
166static 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
172static 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
178int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,
179			    void (*release)(void *), unsigned int index,
180			    unsigned int issue_flags);
181int 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 */