NFSv4: Don't request atime/mtime/size if they are delegated to us

If the timestamps and size are delegated to the client, then it is
authoritative w.r.t. their values, so we should not be requesting those
values from the server.
Note that this allows us to optimise away most GETATTR calls if the only
changes to the attributes are the result of read() or write().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfs4proc.c

@@ -310,6 +310,18 @@ static void nfs4_bitmap_copy_adjust(__u32 *dst, const __u32 *src,
 		dst[1] &= ~FATTR4_WORD1_MODE;
 	if (!(cache_validity & NFS_INO_INVALID_OTHER))
 		dst[1] &= ~(FATTR4_WORD1_OWNER | FATTR4_WORD1_OWNER_GROUP);
+
+	if (nfs_have_delegated_mtime(inode)) {
+		if (!(cache_validity & NFS_INO_INVALID_ATIME))
+			dst[1] &= ~FATTR4_WORD1_TIME_ACCESS;
+		if (!(cache_validity & NFS_INO_INVALID_MTIME))
+			dst[1] &= ~FATTR4_WORD1_TIME_MODIFY;
+		if (!(cache_validity & NFS_INO_INVALID_CTIME))
+			dst[1] &= ~FATTR4_WORD1_TIME_METADATA;
+	} else if (nfs_have_delegated_atime(inode)) {
+		if (!(cache_validity & NFS_INO_INVALID_ATIME))
+			dst[1] &= ~FATTR4_WORD1_TIME_ACCESS;
+	}
 }
 
 static void nfs4_setup_readdir(u64 cookie, __be32 *verifier, struct dentry *dentry,
@@ -3414,7 +3426,8 @@ static int nfs4_do_setattr(struct inode *inode, const struct cred *cred,
 		.inode = inode,
 		.stateid = &arg.stateid,
 	};
-	unsigned long adjust_flags = NFS_INO_INVALID_CHANGE;
+	unsigned long adjust_flags = NFS_INO_INVALID_CHANGE |
+				     NFS_INO_INVALID_CTIME;
 	int err;
 
 	if (sattr->ia_valid & (ATTR_MODE | ATTR_KILL_SUID | ATTR_KILL_SGID))
@@ -4978,8 +4991,9 @@ static int _nfs4_proc_link(struct inode *inode, struct inode *dir, const struct
 		goto out;
 
 	nfs4_inode_make_writeable(inode);
-	nfs4_bitmap_copy_adjust(bitmask, nfs4_bitmask(server, res.fattr->label), inode,
-				NFS_INO_INVALID_CHANGE);
+	nfs4_bitmap_copy_adjust(bitmask, nfs4_bitmask(server, res.fattr->label),
+				inode,
+				NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME);
 	status = nfs4_call_sync(server->client, server, &msg, &arg.seq_args, &res.seq_res, 1);
 	if (!status) {
 		nfs4_update_changeattr(dir, &res.cinfo, res.fattr->time_start,