[PATCH] Better handle NULL utimes() in the NFS client

[John Baldwin]

The NFS client tries to infer when an application has passed NULL to utimes() 
so that it can let the server set the timestamp rather than using a client-
supplied timestamp.  It does this by checking to see if the desired 
timestamp's second matches the current second.  However, this breaks 
applications that are intentionally trying to set a specific timestamp within 
the current second.  In addition, utimes() sets a flag to indicate if NULL was 
passed to utimes().  The patch below changes the NFS client to check this flag 
and only use the server-supplied time in that case:

Index: fs/nfsclient/nfs_clport.c
===================================================================
--- fs/nfsclient/nfs_clport.c	(revision 225511)
+++ fs/nfsclient/nfs_clport.c	(working copy)
@@ -762,7 +762,7 @@
 			*tl = newnfs_false;
 		}
 		if (vap->va_atime.tv_sec != VNOVAL) {
-			if (vap->va_atime.tv_sec != curtime.tv_sec) {
+			if (!(vap->va_vaflags & VA_UTIMES_NULL)) {
 				NFSM_BUILD(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
 				*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 				txdr_nfsv3time(&vap->va_atime, tl);
@@ -775,7 +775,7 @@
 			*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
 		}
 		if (vap->va_mtime.tv_sec != VNOVAL) {
-			if (vap->va_mtime.tv_sec != curtime.tv_sec) {
+			if (!(vap->va_vaflags & VA_UTIMES_NULL)) {
 				NFSM_BUILD(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
 				*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 				txdr_nfsv3time(&vap->va_mtime, tl);
Index: nfsclient/nfs_subs.c
===================================================================
--- nfsclient/nfs_subs.c	(revision 225511)
+++ nfsclient/nfs_subs.c	(working copy)
@@ -1119,7 +1119,7 @@
 		*tl = nfs_false;
 	}
 	if (va->va_atime.tv_sec != VNOVAL) {
-		if (va->va_atime.tv_sec != time_second) {
+		if (!(vattr.va_vaflags & VA_UTIMES_NULL)) {
 			tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
 			*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 			txdr_nfsv3time(&va->va_atime, tl);
@@ -1132,7 +1132,7 @@
 		*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
 	}
 	if (va->va_mtime.tv_sec != VNOVAL) {
-		if (va->va_mtime.tv_sec != time_second) {
+		if (!(vattr.va_vaflags & VA_UTIMES_NULL)) {
 			tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
 			*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 			txdr_nfsv3time(&va->va_mtime, tl);

-- 
John Baldwin