kernel/include/linux/io_uring.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _LINUX_IO_URING_H
#define _LINUX_IO_URING_H

#include <linux/sched.h>
#include <linux/xarray.h>
#include <uapi/linux/io_uring.h>

enum io_uring_cmd_flags {
	IO_URING_F_COMPLETE_DEFER	= 1,
	IO_URING_F_UNLOCKED		= 2,
	/* the request is executed from poll, it should not be freed */
	IO_URING_F_MULTISHOT		= 4,
	/* executed by io-wq */
	IO_URING_F_IOWQ			= 8,
	/* int's last bit, sign checks are usually faster than a bit test */
	IO_URING_F_NONBLOCK		= INT_MIN,

	/* ctx state flags, for URING_CMD */
	IO_URING_F_SQE128		= (1 << 8),
	IO_URING_F_CQE32		= (1 << 9),
	IO_URING_F_IOPOLL		= (1 << 10),

	/* set when uring wants to cancel a previously issued command */
	IO_URING_F_CANCEL		= (1 << 11),
	IO_URING_F_COMPAT		= (1 << 12),
};

/* only top 8 bits of sqe->uring_cmd_flags for kernel internal use */
#define IORING_URING_CMD_CANCELABLE	(1U << 30)
#define IORING_URING_CMD_POLLED		(1U << 31)

struct io_uring_cmd {
	struct file	*file;
	const struct io_uring_sqe *sqe;
	union {
		/* callback to defer completions to task context */
		void (*task_work_cb)(struct io_uring_cmd *cmd, unsigned);
		/* used for polled completion */
		void *cookie;
	};
	u32		cmd_op;
	u32		flags;
	u8		pdu[32]; /* available inline for free use */
};

static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe)
{
	return sqe->cmd;
}

#if defined(CONFIG_IO_URING)
int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
			      struct iov_iter *iter, void *ioucmd);
void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret, ssize_t res2,
			unsigned issue_flags);
struct sock *io_uring_get_socket(struct file *file);
void __io_uring_cancel(bool cancel_all);
void __io_uring_free(struct task_struct *tsk);
void io_uring_unreg_ringfd(void);
const char *io_uring_get_opcode(u8 opcode);
void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
			    void (*task_work_cb)(struct io_uring_cmd *, unsigned),
			    unsigned flags);
/* users should follow semantics of IOU_F_TWQ_LAZY_WAKE */
void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned));

static inline void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned))
{
	__io_uring_cmd_do_in_task(ioucmd, task_work_cb, 0);
}

static inline void io_uring_files_cancel(void)
{
	if (current->io_uring) {
		io_uring_unreg_ringfd();
		__io_uring_cancel(false);
	}
}
static inline void io_uring_task_cancel(void)
{
	if (current->io_uring)
		__io_uring_cancel(true);
}
static inline void io_uring_free(struct task_struct *tsk)
{
	if (tsk->io_uring)
		__io_uring_free(tsk);
}
int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags);
void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
		unsigned int issue_flags);
struct task_struct *io_uring_cmd_get_task(struct io_uring_cmd *cmd);
#else
static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
			      struct iov_iter *iter, void *ioucmd)
{
	return -EOPNOTSUPP;
}
static inline void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret,
		ssize_t ret2, unsigned issue_flags)
{
}
static inline void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned))
{
}
static inline void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned))
{
}
static inline struct sock *io_uring_get_socket(struct file *file)
{
	return NULL;
}
static inline void io_uring_task_cancel(void)
{
}
static inline void io_uring_files_cancel(void)
{
}
static inline void io_uring_free(struct task_struct *tsk)
{
}
static inline const char *io_uring_get_opcode(u8 opcode)
{
	return "";
}
static inline int io_uring_cmd_sock(struct io_uring_cmd *cmd,
				    unsigned int issue_flags)
{
	return -EOPNOTSUPP;
}
static inline void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
		unsigned int issue_flags)
{
}
static inline struct task_struct *io_uring_cmd_get_task(struct io_uring_cmd *cmd)
{
	return NULL;
}
#endif

#endif