svn commit: r195186 - head/sys/ufs/ffs

[Konstantin Belousov]

Author: kib
Date: Tue Jun 30 10:07:00 2009
New Revision: 195186
URL: http://svn.freebsd.org/changeset/base/195186

Log:
  Softdep_fsync() may need to lock parent directory of the synced vnode.
  Use inlined (due to FFSV_FORCEINSMQ) version of vn_vget_ino() to prevent
  mountpoint from being unmounted and freed while no vnodes are locked.
  
  Tested by:	pho
  Approved by:	re (kensmith)
  MFC after:	1 month

Modified:
  head/sys/ufs/ffs/ffs_softdep.c

Modified: head/sys/ufs/ffs/ffs_softdep.c
==============================================================================
--- head/sys/ufs/ffs/ffs_softdep.c	Tue Jun 30 09:51:41 2009	(r195185)
+++ head/sys/ufs/ffs/ffs_softdep.c	Tue Jun 30 10:07:00 2009	(r195186)
@@ -5102,10 +5102,28 @@ softdep_fsync(vp)
 		FREE_LOCK(&lk);
 		if (ffs_vgetf(mp, parentino, LK_NOWAIT | LK_EXCLUSIVE, &pvp,
 		    FFSV_FORCEINSMQ)) {
+			error = vfs_busy(mp, MBF_NOWAIT);
+			if (error != 0) {
+				VOP_UNLOCK(vp, 0);
+				error = vfs_busy(mp, 0);
+				vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+				if (error != 0)
+					return (ENOENT);
+				if (vp->v_iflag & VI_DOOMED) {
+					vfs_unbusy(mp);
+					return (ENOENT);
+				}
+			}
 			VOP_UNLOCK(vp, 0);
 			error = ffs_vgetf(mp, parentino, LK_EXCLUSIVE,
 			    &pvp, FFSV_FORCEINSMQ);
+			vfs_unbusy(mp);
 			vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+			if (vp->v_iflag & VI_DOOMED) {
+				if (error == 0)
+					vput(pvp);
+				error = ENOENT;
+			}
 			if (error != 0)
 				return (error);
 		}