io_uring/poll.h

File Facts

System

Linux kernel

Corpus path

io_uring/poll.h

Extension

.h

Size

1359 bytes

Lines

50

Domain

Kernel Services

Bucket

io_uring

Inferred role

Kernel Services: implementation source

Status

source implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

• Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/io_uring_types.h

Detected Declarations

• struct io_poll
• struct async_poll
• struct io_cancel_data
• function io_poll_multishot_retry

Annotated Snippet

struct io_poll {
	struct file			*file;
	struct wait_queue_head		*head;
	__poll_t			events;
	int				retries;
	struct wait_queue_entry		wait;
};

struct async_poll {
	struct io_poll		poll;
	struct io_poll		*double_poll;
};

/*
 * Must only be called inside issue_flags & IO_URING_F_MULTISHOT, or
 * potentially other cases where we already "own" this poll request.
 */
static inline void io_poll_multishot_retry(struct io_kiocb *req)
{
	atomic_inc(&req->poll_refs);
}

int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_poll_add(struct io_kiocb *req, unsigned int issue_flags);

int io_poll_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags);

struct io_cancel_data;
int io_poll_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd,
		   unsigned issue_flags);
int io_arm_apoll(struct io_kiocb *req, unsigned issue_flags, __poll_t mask);
int io_arm_poll_handler(struct io_kiocb *req, unsigned issue_flags);
bool io_poll_remove_all(struct io_ring_ctx *ctx, struct io_uring_task *tctx,
			bool cancel_all);

void io_poll_task_func(struct io_tw_req tw_req, io_tw_token_t tw);

Annotation

• Immediate include surface: `linux/io_uring_types.h`.
• Detected declarations: `struct io_poll`, `struct async_poll`, `struct io_cancel_data`, `function io_poll_multishot_retry`.
• Atlas domain: Kernel Services / io_uring.
• Implementation status: source implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.