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- Lock access to the buf lists in spec_sync()

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- Fixup interlock locking in spec_close()
This commit is contained in:
Jeff Roberson 2002-09-25 02:29:49 +00:00
parent 75cabb639a
commit c944ebed73
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=103935
1 changed files with 15 additions and 7 deletions
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22
sys/fs/specfs/spec_vnops.c
View file

@ -377,6 +377,7 @@ spec_fsync(ap)
if (!vn_isdisk(vp, NULL))
return (0);
VI_LOCK(vp);
loop1:
/*
* MARK/SCAN initialization to avoid infinite loops.
@ -396,9 +397,12 @@ spec_fsync(ap)
nbp = TAILQ_NEXT(bp, b_vnbufs);
if ((bp->b_flags & B_SCANNED) != 0)
continue;
VI_UNLOCK(vp);
bp->b_flags |= B_SCANNED;
if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT))
if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) {
VI_LOCK(vp);
continue;
}
if ((bp->b_flags & B_DELWRI) == 0)
panic("spec_fsync: not dirty");
if ((vp->v_vflag & VV_OBJBUF) && (bp->b_flags & B_CLUSTEROK)) {
@ -410,6 +414,7 @@ spec_fsync(ap)
splx(s);
bawrite(bp);
}
VI_LOCK(vp);
goto loop2;
}
@ -420,13 +425,11 @@ spec_fsync(ap)
* retry if dirty blocks still exist.
*/
if (ap->a_waitfor == MNT_WAIT) {
VI_LOCK(vp);
while (vp->v_numoutput) {
vp->v_iflag |= VI_BWAIT;
msleep((caddr_t)&vp->v_numoutput, VI_MTX(vp),
PRIBIO + 1, "spfsyn", 0);
}
VI_UNLOCK(vp);
if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
if (--maxretry != 0) {
splx(s);
@ -435,6 +438,7 @@ spec_fsync(ap)
vprint("spec_fsync: giving up on dirty", vp);
}
}
VI_UNLOCK(vp);
splx(s);
return (0);
}
@ -584,7 +588,6 @@ spec_close(ap)
struct thread *td = ap->a_td;
dev_t dev = vp->v_rdev;
mp_fixme("Use of v_iflags bogusly locked.");
/*
* Hack: a tty device that is a controlling terminal
* has a reference from the session structure.
@ -602,10 +605,12 @@ spec_close(ap)
oldvp = NULL;
sx_xlock(&proctree_lock);
if (vcount(vp) == 2 && td && (vp->v_iflag & VI_XLOCK) == 0 &&
vp == td->td_proc->p_session->s_ttyvp) {
if (td && vp == td->td_proc->p_session->s_ttyvp) {
SESS_LOCK(td->td_proc->p_session);
td->td_proc->p_session->s_ttyvp = NULL;
VI_LOCK(vp);
if (vcount(vp) == 2 && (vp->v_iflag & VI_XLOCK) == 0)
td->td_proc->p_session->s_ttyvp = NULL;
VI_UNLOCK(vp);
SESS_UNLOCK(td->td_proc->p_session);
oldvp = vp;
}
@ -621,13 +626,16 @@ spec_close(ap)
* sum of the reference counts on all the aliased
* vnodes descends to one, we are on last close.
*/
VI_LOCK(vp);
if (vp->v_iflag & VI_XLOCK) {
/* Forced close. */
} else if (devsw(dev)->d_flags & D_TRACKCLOSE) {
/* Keep device updated on status. */
} else if (vcount(vp) > 1) {
VI_UNLOCK(vp);
return (0);
}
VI_UNLOCK(vp);
return (devsw(dev)->d_close(dev, ap->a_fflag, S_IFCHR, td));
}