d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
6d8f097966
freebsd-skq/lib/libc/sys/aio_mlock.2

139 lines
4.0 KiB
Groff
Raw Normal View History

Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.\" Copyright (c) 2013 Gleb Smirnoff <glebius@FreeBSD.org>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
Fix various nits in the aio operation manpages. - Avoid double use of "request" in a single sentence. Instead, describe aio_sigevent as being used to request notification of the associated operation's completion. This matches the language used to describe aio_sigevent in aio(4). - Simplify the prohibition on modifying buffers while requests are in flight. - Fix case mismatch. - Drop note about not using stack variables. C programmers should be able to figure out if a stack variable is safe based on the later warning about the life cycle requirements of control blocks. - Remove prohibition on modifying the I/O buffer for aio_fsync() since it does not use an I/O buffer. For aio_mlock(), prohibit modifications to the mapping (e.g. due to mprotect, munmap, mmap, etc.) but do not prohibit modifications to the memory backing the buffer (stores into the pages backing the buffer). Requested by: wblock (1,2), kib (4) Reviewed by: kib, rpokala, wblock MFC after: 3 days Sponsored by: Chelsio Communications Differential Revision: https://reviews.freebsd.org/D7462
2016-08-19 17:37:32 +00:00
.Dd August 19, 2016
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.Dt AIO_MLOCK 2
.Os
.Sh NAME
.Nm aio_mlock
.Nd asynchronous
.Xr mlock 2
operation
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In aio.h
.Ft int
.Fn aio_mlock "struct aiocb *iocb"
.Sh DESCRIPTION
The
.Fn aio_mlock
system call allows the calling process to lock into memory the
physical pages associated with the virtual address range starting at
.Fa iocb->aio_buf
for
.Fa 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.
.Pp
The
.Fa iocb
pointer may be subsequently used as an argument to
.Fn aio_return
and
.Fn aio_error
in order to determine return or error status for the enqueued operation
while it is in progress.
.Pp
Minor mdoc fixes.
2013-06-09 07:15:43 +00:00
If the request could not be enqueued (generally due to
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.Xr aio 4
limits),
then the call returns without having enqueued the request.
Add documentation for the sigevent structure. - Add a sigevent(3) manpage to give a general overview of the sigevent structure and the available notification mechanisms. - Document that AIO requests contain a nested sigevent structure that can be used to request completion notification. - Expand the sigevent details in other manuals to note details such as the extra values stored in a queued signal's information or in a posted kevent. Reviewed by: kib MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D7122
2016-07-15 15:12:56 +00:00
.Pp
The
.Fa iocb->aio_sigevent
Fix various nits in the aio operation manpages. - Avoid double use of "request" in a single sentence. Instead, describe aio_sigevent as being used to request notification of the associated operation's completion. This matches the language used to describe aio_sigevent in aio(4). - Simplify the prohibition on modifying buffers while requests are in flight. - Fix case mismatch. - Drop note about not using stack variables. C programmers should be able to figure out if a stack variable is safe based on the later warning about the life cycle requirements of control blocks. - Remove prohibition on modifying the I/O buffer for aio_fsync() since it does not use an I/O buffer. For aio_mlock(), prohibit modifications to the mapping (e.g. due to mprotect, munmap, mmap, etc.) but do not prohibit modifications to the memory backing the buffer (stores into the pages backing the buffer). Requested by: wblock (1,2), kib (4) Reviewed by: kib, rpokala, wblock MFC after: 3 days Sponsored by: Chelsio Communications Differential Revision: https://reviews.freebsd.org/D7462
2016-08-19 17:37:32 +00:00
structure can be used to request notification of the operation's
Add documentation for the sigevent structure. - Add a sigevent(3) manpage to give a general overview of the sigevent structure and the available notification mechanisms. - Document that AIO requests contain a nested sigevent structure that can be used to request completion notification. - Expand the sigevent details in other manuals to note details such as the extra values stored in a queued signal's information or in a posted kevent. Reviewed by: kib MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D7122
2016-07-15 15:12:56 +00:00
completion as described in
.Xr aio 4 .
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.Sh RESTRICTIONS
The Asynchronous I/O Control Block structure pointed to by
.Fa iocb
and the buffer that the
.Fa iocb->aio_buf
member of that structure references must remain valid until the
operation has completed.
.Pp
The asynchronous I/O control buffer
.Fa iocb
should be zeroed before the
.Fn aio_mlock
call to avoid passing bogus context information to the kernel.
.Pp
Modifications of the Asynchronous I/O Control Block structure or the
Fix various nits in the aio operation manpages. - Avoid double use of "request" in a single sentence. Instead, describe aio_sigevent as being used to request notification of the associated operation's completion. This matches the language used to describe aio_sigevent in aio(4). - Simplify the prohibition on modifying buffers while requests are in flight. - Fix case mismatch. - Drop note about not using stack variables. C programmers should be able to figure out if a stack variable is safe based on the later warning about the life cycle requirements of control blocks. - Remove prohibition on modifying the I/O buffer for aio_fsync() since it does not use an I/O buffer. For aio_mlock(), prohibit modifications to the mapping (e.g. due to mprotect, munmap, mmap, etc.) but do not prohibit modifications to the memory backing the buffer (stores into the pages backing the buffer). Requested by: wblock (1,2), kib (4) Reviewed by: kib, rpokala, wblock MFC after: 3 days Sponsored by: Chelsio Communications Differential Revision: https://reviews.freebsd.org/D7462
2016-08-19 17:37:32 +00:00
memory mapping described by the virtual address range are not allowed
while the request is queued.
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.Sh RETURN VALUES
.Rv -std aio_mlock
.Sh ERRORS
The
Fix an apparent typo. MFC after: 3 days
2013-12-26 19:18:43 +00:00
.Fn aio_mlock
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
system call will fail if:
.Bl -tag -width Er
.It Bq Er EAGAIN
The request was not queued because of system resource limitations.
Add documentation for the sigevent structure. - Add a sigevent(3) manpage to give a general overview of the sigevent structure and the available notification mechanisms. - Document that AIO requests contain a nested sigevent structure that can be used to request completion notification. - Expand the sigevent details in other manuals to note details such as the extra values stored in a queued signal's information or in a posted kevent. Reviewed by: kib MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D7122
2016-07-15 15:12:56 +00:00
.It Bq Er EINVAL
The asynchronous notification method in
.Fa iocb->aio_sigevent.sigev_notify
is invalid or not supported.
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.El
.Pp
If the request is successfully enqueued, but subsequently cancelled
or an error occurs, the value returned by the
.Fn aio_return
system call is per the
.Xr mlock 2
system call, and the value returned by the
.Fn aio_error
system call is one of the error returns from the
.Xr mlock 2
system call, or
.Er ECANCELED
if the request was explicitly cancelled via a call to
.Fn aio_cancel .
.Sh SEE ALSO
.Xr aio_cancel 2 ,
.Xr aio_error 2 ,
.Xr aio_return 2 ,
Minor mdoc fixes.
2013-06-09 07:15:43 +00:00
.Xr mlock 2 ,
Add documentation for the sigevent structure. - Add a sigevent(3) manpage to give a general overview of the sigevent structure and the available notification mechanisms. - Document that AIO requests contain a nested sigevent structure that can be used to request completion notification. - Expand the sigevent details in other manuals to note details such as the extra values stored in a queued signal's information or in a posted kevent. Reviewed by: kib MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D7122
2016-07-15 15:12:56 +00:00
.Xr sigevent 3 ,
Minor mdoc fixes.
2013-06-09 07:15:43 +00:00
.Xr aio 4
Add new system call - aio_mlock(). The name speaks for itself. It allows to perform the mlock(2) operation, which can consume a lot of time, under control of aio(4). Reviewed by: kib, jilles Sponsored by: Nginx, Inc.
2013-06-08 13:27:57 +00:00
.Sh PORTABILITY
The
.Fn aio_mlock
system call is a
.Fx
extension, and should not be used in portable code.
.Sh HISTORY
The
.Fn aio_mlock
system call first appeared in
.Fx 10.0 .
.Sh AUTHORS
The system call was introduced by
use .Mt to mark up email addresses consistently (part4) PR: 191174 Submitted by: Franco Fichtner <franco at lastsummer.de>
2014-06-23 08:25:03 +00:00
.An Gleb Smirnoff Aq Mt glebius@FreeBSD.org .
Reference in New Issue Copy Permalink