diff options
Diffstat (limited to 'sys/kern/vfs_vops.c')
| -rw-r--r-- | sys/kern/vfs_vops.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/sys/kern/vfs_vops.c b/sys/kern/vfs_vops.c index 9c39ab07705..e606c0b8af7 100644 --- a/sys/kern/vfs_vops.c +++ b/sys/kern/vfs_vops.c @@ -1,4 +1,4 @@ -/* $OpenBSD: vfs_vops.c,v 1.21 2019/05/03 14:24:13 visa Exp $ */ +/* $OpenBSD: vfs_vops.c,v 1.22 2019/08/26 18:56:29 anton Exp $ */ /* * Copyright (c) 2010 Thordur I. Bjornsson <thib@openbsd.org> * @@ -46,6 +46,7 @@ #include <sys/vnode.h> #include <sys/unistd.h> #include <sys/systm.h> +#include <sys/lock.h> /* LK_DRAIN */ #ifdef VFSLCKDEBUG #include <sys/systm.h> /* for panic() */ @@ -599,6 +600,17 @@ VOP_LOCK(struct vnode *vp, int flags) if (vp->v_op->vop_lock == NULL) return (EOPNOTSUPP); + if ((flags & LK_DRAIN) && vp->v_lockcount > 0) { + /* + * Ensure that any thread currently waiting on the same lock has + * observed that the vnode is about to be exclusively locked + * before continuing. + */ + KASSERT(vp->v_flag & VXLOCK); + tsleep(&vp->v_lockcount, PINOD, "vop_lock", 0); + KASSERT(vp->v_lockcount == 0); + } + return ((vp->v_op->vop_lock)(&a)); } |