Index: linux-2.6.32-el6-beta/fs/ext4/ialloc.c
===================================================================
--- linux-2.6.32-el6-beta.orig/fs/ext4/ialloc.c
+++ linux-2.6.32-el6-beta/fs/ext4/ialloc.c
@@ -825,11 +825,15 @@ struct inode *ext4_new_inode(handle_t *h
 	sb = dir->i_sb;
 	ngroups = ext4_get_groups_count(sb);
 	trace_ext4_request_inode(dir, mode);
+
+	sbi = EXT4_SB(sb);
+	if (sbi->s_max_dir_size > 0 && i_size_read(dir) >= sbi->s_max_dir_size)
+		return ERR_PTR(-EFBIG);
+
 	inode = new_inode(sb);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 	ei = EXT4_I(inode);
-	sbi = EXT4_SB(sb);
 
 	if (!goal)
 		goal = sbi->s_inode_goal;
Index: linux-2.6.32-el6-beta/fs/ext4/super.c
===================================================================
--- linux-2.6.32-el6-beta.orig/fs/ext4/super.c
+++ linux-2.6.32-el6-beta/fs/ext4/super.c
@@ -2601,6 +2601,7 @@ EXT4_RO_ATTR(lifetime_write_kbytes);
 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
 		 inode_readahead_blks_store, s_inode_readahead_blks);
 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
+EXT4_RW_ATTR_SBI_UI(max_dir_size, s_max_dir_size);
 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
@@ -2615,6 +2616,7 @@ static struct attribute *ext4_attrs[] = 
 	ATTR_LIST(lifetime_write_kbytes),
 	ATTR_LIST(inode_readahead_blks),
 	ATTR_LIST(inode_goal),
+	ATTR_LIST(max_dir_size),
 	ATTR_LIST(mb_stats),
 	ATTR_LIST(mb_max_to_scan),
 	ATTR_LIST(mb_min_to_scan),
Index: linux-2.6.32-el6-beta/fs/ext4/ext4.h
===================================================================
--- linux-2.6.32-el6-beta.orig/fs/ext4/ext4.h
+++ linux-2.6.32-el6-beta/fs/ext4/ext4.h
@@ -1029,6 +1029,8 @@ struct ext4_sb_info {
 
 	/* Kernel thread for multiple mount protection */
 	struct task_struct *s_mmp_tsk;
+
+	unsigned long s_max_dir_size;
 };
 
 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
@@ -1353,6 +1355,12 @@ struct mmp_struct {
 #define EXT4_MMP_MIN_CHECK_INTERVAL	5
 
 /*
+ * max directory size tunable
+ */
+#define EXT4_DEFAULT_MAX_DIR_SIZE	0
+#define EXT4_MAX_DIR_SIZE_NAME		"max_dir_size"
+
+/*
  * Function prototypes
  */