fs: encode_fh: return FILEID_INVALID if invalid fid_type

This patch is a follow up on below patch:

[PATCH] exportfs: add FILEID_INVALID to indicate invalid fid_type
commit: 216b6cbdcbd86b1db0754d58886b466ae31f5a63

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Sage Weil <sage@inktank.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
index 614f34a..81ee29e 100644
--- a/fs/btrfs/export.c
+++ b/fs/btrfs/export.c
@@ -22,10 +22,10 @@
 
 	if (parent && (len < BTRFS_FID_SIZE_CONNECTABLE)) {
 		*max_len = BTRFS_FID_SIZE_CONNECTABLE;
-		return 255;
+		return FILEID_INVALID;
 	} else if (len < BTRFS_FID_SIZE_NON_CONNECTABLE) {
 		*max_len = BTRFS_FID_SIZE_NON_CONNECTABLE;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	len  = BTRFS_FID_SIZE_NON_CONNECTABLE;
diff --git a/fs/ceph/export.c b/fs/ceph/export.c
index ca3ab3f..16796be 100644
--- a/fs/ceph/export.c
+++ b/fs/ceph/export.c
@@ -81,7 +81,7 @@
 		if (parent_inode) {
 			/* nfsd wants connectable */
 			*max_len = connected_handle_length;
-			type = 255;
+			type = FILEID_INVALID;
 		} else {
 			dout("encode_fh %p\n", dentry);
 			fh->ino = ceph_ino(inode);
@@ -90,7 +90,7 @@
 		}
 	} else {
 		*max_len = handle_length;
-		type = 255;
+		type = FILEID_INVALID;
 	}
 	if (dentry)
 		dput(dentry);
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 73ca6b7..b730fda 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -678,7 +678,7 @@
 
 	if (*max_len < len) {
 		*max_len = len;
-		return  255;
+		return  FILEID_INVALID;
 	}
 
 	nodeid = get_fuse_inode(inode)->nodeid;
diff --git a/fs/gfs2/export.c b/fs/gfs2/export.c
index 4767774..9973df4 100644
--- a/fs/gfs2/export.c
+++ b/fs/gfs2/export.c
@@ -37,10 +37,10 @@
 
 	if (parent && (*len < GFS2_LARGE_FH_SIZE)) {
 		*len = GFS2_LARGE_FH_SIZE;
-		return 255;
+		return FILEID_INVALID;
 	} else if (*len < GFS2_SMALL_FH_SIZE) {
 		*len = GFS2_SMALL_FH_SIZE;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
diff --git a/fs/isofs/export.c b/fs/isofs/export.c
index 2b4f235..12088d8 100644
--- a/fs/isofs/export.c
+++ b/fs/isofs/export.c
@@ -125,10 +125,10 @@
 	 */
 	if (parent && (len < 5)) {
 		*max_len = 5;
-		return 255;
+		return FILEID_INVALID;
 	} else if (len < 3) {
 		*max_len = 3;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	len = 3;
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index 1d0c0b8..9de78f0 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -517,11 +517,11 @@
 
 	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
 		*lenp = NILFS_FID_SIZE_CONNECTABLE;
-		return 255;
+		return FILEID_INVALID;
 	}
 	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
 		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	fid->cno = root->cno;
diff --git a/fs/ocfs2/export.c b/fs/ocfs2/export.c
index 322216a..2965116 100644
--- a/fs/ocfs2/export.c
+++ b/fs/ocfs2/export.c
@@ -195,11 +195,11 @@
 
 	if (parent && (len < 6)) {
 		*max_len = 6;
-		type = 255;
+		type = FILEID_INVALID;
 		goto bail;
 	} else if (len < 3) {
 		*max_len = 3;
-		type = 255;
+		type = FILEID_INVALID;
 		goto bail;
 	}
 
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 95d7680..ea5061fd 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -1603,10 +1603,10 @@
 
 	if (parent && (maxlen < 5)) {
 		*lenp = 5;
-		return 255;
+		return FILEID_INVALID;
 	} else if (maxlen < 3) {
 		*lenp = 3;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	data[0] = inode->i_ino;
diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index 95fee27..102c072 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -1270,10 +1270,10 @@
 
 	if (parent && (len < 5)) {
 		*lenp = 5;
-		return 255;
+		return FILEID_INVALID;
 	} else if (len < 3) {
 		*lenp = 3;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	*lenp = 3;
diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c
index a836118..c585bc6 100644
--- a/fs/xfs/xfs_export.c
+++ b/fs/xfs/xfs_export.c
@@ -48,7 +48,7 @@
 	case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
 		return 6;
 	}
-	return 255; /* invalid */
+	return FILEID_INVALID;
 }
 
 STATIC int
@@ -90,7 +90,7 @@
 	len = xfs_fileid_length(fileid_type);
 	if (*max_len < len) {
 		*max_len = len;
-		return 255;
+		return FILEID_INVALID;
 	}
 	*max_len = len;
 
diff --git a/mm/cleancache.c b/mm/cleancache.c
index 32e6f41..d76ba74 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -89,7 +89,7 @@
 		fhfn = sb->s_export_op->encode_fh;
 		if  (fhfn) {
 			len = (*fhfn)(inode, &key->u.fh[0], &maxlen, NULL);
-			if (len <= 0 || len == 255)
+			if (len <= FILEID_ROOT || len == FILEID_INVALID)
 				return -1;
 			if (maxlen > CLEANCACHE_KEY_MAX)
 				return -1;
diff --git a/mm/shmem.c b/mm/shmem.c
index 25cd688..320ffc1 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2351,7 +2351,7 @@
 {
 	if (*len < 3) {
 		*len = 3;
-		return 255;
+		return FILEID_INVALID;
 	}
 
 	if (inode_unhashed(inode)) {