freebsd-dev/sys/ufs/ffs/ffs_vnops.c
Kirk McKusick 589c7af992 Fixes to track snapshot copy-on-write checking in the specinfo
structure rather than assuming that the device vnode would reside
in the FFS filesystem (which is obviously a broken assumption with
the device filesystem).
2001-03-07 07:09:55 +00:00

300 lines
8.8 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)ffs_vnops.c 8.15 (Berkeley) 5/14/95
* $FreeBSD$
*/
#include "opt_ffs.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <machine/limits.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <ufs/ufs/extattr.h>
#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>
#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>
int ffs_fsync __P((struct vop_fsync_args *));
static int ffs_getpages __P((struct vop_getpages_args *));
static int ffs_putpages __P((struct vop_putpages_args *));
static int ffs_read __P((struct vop_read_args *));
static int ffs_write __P((struct vop_write_args *));
/* Global vfs data structures for ufs. */
vop_t **ffs_vnodeop_p;
static struct vnodeopv_entry_desc ffs_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperate },
{ &vop_fsync_desc, (vop_t *) ffs_fsync },
{ &vop_getpages_desc, (vop_t *) ffs_getpages },
{ &vop_putpages_desc, (vop_t *) ffs_putpages },
{ &vop_read_desc, (vop_t *) ffs_read },
{ &vop_balloc_desc, (vop_t *) ffs_balloc },
{ &vop_reallocblks_desc, (vop_t *) ffs_reallocblks },
{ &vop_write_desc, (vop_t *) ffs_write },
#ifdef FFS_EXTATTR
{ &vop_getextattr_desc, (vop_t *) ufs_vop_getextattr },
{ &vop_setextattr_desc, (vop_t *) ufs_vop_setextattr },
#endif
{ NULL, NULL }
};
static struct vnodeopv_desc ffs_vnodeop_opv_desc =
{ &ffs_vnodeop_p, ffs_vnodeop_entries };
vop_t **ffs_specop_p;
static struct vnodeopv_entry_desc ffs_specop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperatespec },
{ &vop_fsync_desc, (vop_t *) ffs_fsync },
#ifdef FFS_EXTATTR
{ &vop_getextattr_desc, (vop_t *) ufs_vop_getextattr },
{ &vop_setextattr_desc, (vop_t *) ufs_vop_setextattr },
#endif
{ NULL, NULL }
};
static struct vnodeopv_desc ffs_specop_opv_desc =
{ &ffs_specop_p, ffs_specop_entries };
vop_t **ffs_fifoop_p;
static struct vnodeopv_entry_desc ffs_fifoop_entries[] = {
{ &vop_default_desc, (vop_t *) ufs_vnoperatefifo },
#ifdef FFS_EXTATTR
{ &vop_getextattr_desc, (vop_t *) ufs_vop_getextattr },
{ &vop_setextattr_desc, (vop_t *) ufs_vop_setextattr },
#endif
{ &vop_fsync_desc, (vop_t *) ffs_fsync },
{ NULL, NULL }
};
static struct vnodeopv_desc ffs_fifoop_opv_desc =
{ &ffs_fifoop_p, ffs_fifoop_entries };
VNODEOP_SET(ffs_vnodeop_opv_desc);
VNODEOP_SET(ffs_specop_opv_desc);
VNODEOP_SET(ffs_fifoop_opv_desc);
#include <ufs/ufs/ufs_readwrite.c>
/*
* Synch an open file.
*/
/* ARGSUSED */
int
ffs_fsync(ap)
struct vop_fsync_args /* {
struct vnode *a_vp;
struct ucred *a_cred;
int a_waitfor;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct buf *bp;
struct buf *nbp;
int s, error, wait, passes, skipmeta;
daddr_t lbn;
/*
* Snapshots have to be unlocked so they do not deadlock
* checking whether they need to copy their written buffers.
* We always hold a reference, so they cannot be removed
* out from underneath us.
*/
if (ip->i_flags & SF_SNAPSHOT)
VOP_UNLOCK(vp, 0, ap->a_p);
wait = (ap->a_waitfor == MNT_WAIT);
if (vn_isdisk(vp, NULL)) {
lbn = INT_MAX;
if (vp->v_rdev->si_mountpoint != NULL &&
(vp->v_rdev->si_mountpoint->mnt_flag & MNT_SOFTDEP))
softdep_fsync_mountdev(vp);
} else {
lbn = lblkno(ip->i_fs, (ip->i_size + ip->i_fs->fs_bsize - 1));
}
/*
* Flush all dirty buffers associated with a vnode.
*/
passes = NIADDR + 1;
skipmeta = 0;
if (wait)
skipmeta = 1;
s = splbio();
loop:
TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs)
bp->b_flags &= ~B_SCANNED;
for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
nbp = TAILQ_NEXT(bp, b_vnbufs);
/*
* Reasons to skip this buffer: it has already been considered
* on this pass, this pass is the first time through on a
* synchronous flush request and the buffer being considered
* is metadata, the buffer has dependencies that will cause
* it to be redirtied and it has not already been deferred,
* or it is already being written.
*/
if ((bp->b_flags & B_SCANNED) != 0)
continue;
bp->b_flags |= B_SCANNED;
if ((skipmeta == 1 && bp->b_lblkno < 0))
continue;
if (!wait && LIST_FIRST(&bp->b_dep) != NULL &&
(bp->b_flags & B_DEFERRED) == 0 &&
buf_countdeps(bp, 0)) {
bp->b_flags |= B_DEFERRED;
continue;
}
if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT))
continue;
if ((bp->b_flags & B_DELWRI) == 0)
panic("ffs_fsync: not dirty");
if (vp != bp->b_vp)
panic("ffs_fsync: vp != vp->b_vp");
/*
* If this is a synchronous flush request, or it is not a
* file or device, start the write on this buffer immediatly.
*/
if (wait || (vp->v_type != VREG && vp->v_type != VBLK)) {
/*
* On our final pass through, do all I/O synchronously
* so that we can find out if our flush is failing
* because of write errors.
*/
if (passes > 0 || !wait) {
if ((bp->b_flags & B_CLUSTEROK) && !wait) {
BUF_UNLOCK(bp);
(void) vfs_bio_awrite(bp);
} else {
bremfree(bp);
splx(s);
(void) bawrite(bp);
s = splbio();
}
} else {
bremfree(bp);
splx(s);
if ((error = bwrite(bp)) != 0)
return (error);
s = splbio();
}
} else if ((vp->v_type == VREG) && (bp->b_lblkno >= lbn)) {
/*
* If the buffer is for data that has been truncated
* off the file, then throw it away.
*/
bremfree(bp);
bp->b_flags |= B_INVAL | B_NOCACHE;
splx(s);
brelse(bp);
s = splbio();
} else {
BUF_UNLOCK(bp);
vfs_bio_awrite(bp);
}
/*
* Since we may have slept during the I/O, we need
* to start from a known point.
*/
nbp = TAILQ_FIRST(&vp->v_dirtyblkhd);
}
/*
* If we were asked to do this synchronously, then go back for
* another pass, this time doing the metadata.
*/
if (skipmeta) {
skipmeta = 0;
goto loop;
}
if (wait) {
while (vp->v_numoutput) {
vp->v_flag |= VBWAIT;
(void) tsleep((caddr_t)&vp->v_numoutput,
PRIBIO + 4, "ffsfsn", 0);
}
/*
* Ensure that any filesystem metatdata associated
* with the vnode has been written.
*/
splx(s);
if ((error = softdep_sync_metadata(ap)) != 0)
return (error);
s = splbio();
if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
/*
* Block devices associated with filesystems may
* have new I/O requests posted for them even if
* the vnode is locked, so no amount of trying will
* get them clean. Thus we give block devices a
* good effort, then just give up. For all other file
* types, go around and try again until it is clean.
*/
if (passes > 0) {
passes -= 1;
goto loop;
}
#ifdef DIAGNOSTIC
if (!vn_isdisk(vp, NULL))
vprint("ffs_fsync: dirty", vp);
#endif
}
}
splx(s);
error = UFS_UPDATE(vp, wait);
if (ip->i_flags & SF_SNAPSHOT)
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, ap->a_p);
return (error);
}