io_getevents

read asynchronous I/O events from the completion queue

sys_io_getevents(aio_context_t ctx_id, long min_nr, long nr, struct io_event *events, struct __kernel_timespec *timeout)

register	value
`a7`	4, the syscall number
`a0`	aio_context_t ctx_id
`a1`	long min_nr
`a2`	long nr
`a3`	struct io_event *events
`a4`	struct __kernel_timespec *timeout
`a0`	the return value

Then run ecall to enter the kernel.

Same syscall on other architectures