diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 886f609..1604a8a 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -537,7 +537,7 @@
 	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
 
 	/* If the count of free cluster is still unknown, counts it here. */
-	if (sbi->free_clusters == -1) {
+	if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
 		int err = fat_count_free_clusters(dentry->d_sb);
 		if (err)
 			return err;
@@ -1274,6 +1274,7 @@
 	sbi->fat_length = le16_to_cpu(b->fat_length);
 	sbi->root_cluster = 0;
 	sbi->free_clusters = -1;	/* Don't know yet */
+	sbi->free_clus_valid = 0;
 	sbi->prev_free = FAT_START_ENT;
 
 	if (!sbi->fat_length && b->fat32_length) {
@@ -1309,8 +1310,8 @@
 			       sbi->fsinfo_sector);
 		} else {
 			if (sbi->options.usefree)
-				sbi->free_clusters =
-					le32_to_cpu(fsinfo->free_clusters);
+				sbi->free_clus_valid = 1;
+			sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
 			sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
 		}