svn commit: r223971 - head/sys/fs/nfsclient

[Rick Macklem]

Author: rmacklem
Date: Wed Jul 13 00:48:36 2011
New Revision: 223971
URL: http://svn.freebsd.org/changeset/base/223971

Log:
  r222389 introduced a case where the NFSv4 client could
  loop in nfscl_getcl() when a forced dismount is in progress,
  because nfsv4_lock() will return 0 without sleeping when
  MNTK_UNMOUNTF is set.
  This patch fixes it so it won't loop calling nfsv4_lock()
  for this case.
  
  MFC after:	2 weeks

Modified:
  head/sys/fs/nfsclient/nfs_clstate.c

Modified: head/sys/fs/nfsclient/nfs_clstate.c
==============================================================================
--- head/sys/fs/nfsclient/nfs_clstate.c	Tue Jul 12 23:48:57 2011	(r223970)
+++ head/sys/fs/nfsclient/nfs_clstate.c	Wed Jul 13 00:48:36 2011	(r223971)
@@ -761,7 +761,8 @@ nfscl_getcl(vnode_t vp, struct ucred *cr
 			FREE((caddr_t)newclp, M_NFSCLCLIENT);
 	}
 	NFSLOCKCLSTATE();
-	while ((clp->nfsc_flags & NFSCLFLAGS_HASCLIENTID) == 0 && !igotlock)
+	while ((clp->nfsc_flags & NFSCLFLAGS_HASCLIENTID) == 0 && !igotlock &&
+	    (mp->mnt_kern_flag & MNTK_UNMOUNTF) == 0)
 		igotlock = nfsv4_lock(&clp->nfsc_lock, 1, NULL,
 		    NFSCLSTATEMUTEXPTR, mp);
 	if (!igotlock)