142 lines
3.5 KiB
Groff
142 lines
3.5 KiB
Groff
.\" -*- nroff -*-
|
|
.\"
|
|
.\" Copyright (c) 1996 Doug Rabson
|
|
.\"
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This program is free software.
|
|
.\"
|
|
.\" 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 DEVELOPERS ``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 DEVELOPERS 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.
|
|
.\"
|
|
.\" $Id: VOP_FSYNC.9,v 1.4 1997/04/13 14:48:52 bde Exp $
|
|
.\"
|
|
.Dd July 24, 1996
|
|
.Os
|
|
.Dt VOP_FSYNC 9
|
|
.Sh NAME
|
|
.Nm VOP_FSYNC
|
|
.Nd flush filesystem buffers for a file
|
|
.Sh SYNOPSIS
|
|
.Fd #include <sys/param.h>
|
|
.Fd #include <sys/vnode.h>
|
|
.Ft int
|
|
.Fn VOP_FSYNC "struct vnode *vp" "struct ucred *cred" "int waitfor" "struct proc *p"
|
|
.Sh DESCRIPTION
|
|
This call flushes any dirty filesystem buffers for the file.
|
|
It is used to implement the
|
|
.Xr sync 2
|
|
and
|
|
.Xr fsync 2
|
|
system calls.
|
|
.Pp
|
|
Its arguments are:
|
|
.Bl -tag -width waitfor
|
|
.It Ar vp
|
|
the vnode of the file
|
|
.It Ar cred
|
|
the caller's credentials
|
|
.It Ar waitfor
|
|
whether the function should wait for I/O to complete
|
|
.It Ar p
|
|
the calling process
|
|
.El
|
|
.Pp
|
|
The argument
|
|
.Fa waitfor
|
|
is either
|
|
.Dv MNT_WAIT
|
|
or
|
|
.Dv MNT_NOWAIT
|
|
and specifies whether or not the function should wait for the writes
|
|
to finish before returning.
|
|
.Sh LOCKS
|
|
The file should be locked on entry.
|
|
.Sh RETURN VALUES
|
|
Zero is returned if the call is successful, otherwise an appropriate
|
|
error code is returned.
|
|
.Sh PSEUDOCODE
|
|
.Bd -literal
|
|
int
|
|
vop_fsync(struct vnode *vp, struct ucred *cred, int waitfor, struct proc *p)
|
|
{
|
|
struct buf *bp;
|
|
struct buf *nbp;
|
|
struct timeval tv;
|
|
int s;
|
|
|
|
loop:
|
|
s = splbio();
|
|
for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
|
|
nbp = bp->b_vnbufs.le_next;
|
|
|
|
/*
|
|
* Ignore buffers which are already being written.
|
|
*/
|
|
if (bp->b_flags & B_BUSY)
|
|
continue;
|
|
|
|
/*
|
|
* Make sure the buffer is dirty.
|
|
*/
|
|
if ((bp->b_flags & B_DELWRI) == 0)
|
|
panic("vop_fsync: not dirty");
|
|
|
|
vfs_bio_awrite(bp);
|
|
splx(s);
|
|
goto loop;
|
|
}
|
|
splx(s);
|
|
|
|
if (waitfor == MNT_WAIT) {
|
|
s = splbio();
|
|
while (vp->v_numoutput) {
|
|
vp->v_flag |= VBWAIT;
|
|
tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "vopfsn");
|
|
}
|
|
splx(s);
|
|
#ifdef DIAGNOSTIC
|
|
if (vp->v_dirtyblkhd.lh_first) {
|
|
vprint("vop_fsync: dirty", vp);
|
|
goto loop;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Write out the on-disc version of the vnode.
|
|
*/
|
|
tv = time;
|
|
return VOP_UPDATE(vp, &tv, &tv, waitfor == MNT_WAIT);
|
|
}
|
|
.Ed
|
|
.Sh ERRORS
|
|
.Bl -tag -width Er
|
|
.It Bq Er ENOSPC
|
|
The filesystem is full.
|
|
.It Bq Er EDQUOT
|
|
Quota exceeded.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr vnode 9
|
|
.Sh AUTHORS
|
|
This man page was written by
|
|
.An Doug Rabson .
|