KATO Takenori a9320ff3bd Revised fix for locking violation when unionfs calls vput with ... UN_KLOCK flag. When UN_KLOCK is set, VOP_UNLOCK should keep uppervp locked and clear UN_ULOCK flag. To do this, when UN_KLOCK is set, (1) union_unlock clears UN_ULOCK and does not clear UN_KLOCK, (2) union_lock() does not access uppervp and does not clear UN_KLOCK, and (3) callers of vput/VOP_UNLOCK should clear UN_KLOCK. For example, vput becomes: SETKLOCK(union_node); vput(vnode); CLEARKLOCK(union_node); where SETKLOCK macro sets UN_KLOCK and CLEARKLOCK macro clears UN_KLOCK.		1997-04-29 02:06:07 +00:00
..
union_subr.c	Do not set the uppervp to NULLVP in union_removed_upper. If lowervp	1997-04-16 16:24:24 +00:00
union_vfsops.c	Avoid `lock against myself' panic by following operation:	1997-04-19 06:04:13 +00:00
union_vnops.c	Revised fix for locking violation when unionfs calls vput with	1997-04-29 02:06:07 +00:00
union.h	Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not	1997-02-22 09:48:43 +00:00