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AIO_MLOCK(2) FreeBSD System Calls Manual AIO_MLOCK(2)
NAME
aio_mlock - asynchronous mlock(2) operation
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <aio.h>
int
aio_mlock(struct aiocb *iocb);
DESCRIPTION
The aio_mlock() system call allows the calling process to lock into
memory the physical pages associated with the virtual address range
starting at iocb->aio_buf for iocb->aio_nbytes bytes. The call returns
immediately after the locking request has been enqueued; the operation
may or may not have completed at the time the call returns.
The iocb pointer may be subsequently used as an argument to aio_return()
and aio_error() in order to determine return or error status for the
enqueued operation while it is in progress.
If the request could not be enqueued (generally due to aio(4) limits),
then the call returns without having enqueued the request.
The iocb->aio_sigevent structure can be used to request notification of
the operation's completion as described in aio(4).
RESTRICTIONS
The Asynchronous I/O Control Block structure pointed to by iocb and the
buffer that the iocb->aio_buf member of that structure references must
remain valid until the operation has completed.
The asynchronous I/O control buffer iocb should be zeroed before the
aio_mlock() call to avoid passing bogus context information to the
kernel.
Modifications of the Asynchronous I/O Control Block structure or the
memory mapping described by the virtual address range are not allowed
while the request is queued.
RETURN VALUES
The aio_mlock() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
The aio_mlock() system call will fail if:
[EAGAIN] The request was not queued because of system resource
limitations.
[EINVAL] The asynchronous notification method in
iocb->aio_sigevent.sigev_notify is invalid or not
supported.
SEE ALSO
aio_cancel(2), aio_error(2), aio_return(2), mlock(2), sigevent(3), aio(4)
PORTABILITY
The aio_mlock() system call is a FreeBSD extension, and should not be
used in portable code.
HISTORY
The aio_mlock() system call first appeared in FreeBSD 10.0.
AUTHORS
The system call was introduced by Gleb Smirnoff <glebius@FreeBSD.org>.
FreeBSD 14.0-RELEASE-p6 August 19, 2016 FreeBSD 14.0-RELEASE-p6