e2fsck/pass4.c           | 12 +++++++++-
e2fsck/problem.c         |  5 ++++
e2fsck/problem.h         |  3 +++
tests/f_large_dir/expect |  7 ++++--
tests/f_large_dir/script | 60 ++++++++++++++++++++++++++++++------------------
5 files changed, 62 insertions(+), 25 deletions(-)

diff --git a/e2fsck/pass4.c b/e2fsck/pass4.c
index 663f87a..d0ff8e9 100644
--- a/e2fsck/pass4.c
+++ b/e2fsck/pass4.c

@@ -170,6 +170,7 @@ void e2fsck_pass4(e2fsck_t ctx)

#endif
	struct problem_context	pctx;
	__u16	link_count, link_counted;
+	int dir_nlink_fs;
	char	*buf = 0;
	dgrp_t	group, maxgroup;

@@ -193,6 +194,8 @@ void e2fsck_pass4(e2fsck_t ctx)

	if (!(ctx->options & E2F_OPT_PREEN))
		fix_problem(ctx, PR_4_PASS_HEADER, &pctx);

+	dir_nlink_fs = ext2fs_has_feature_dir_nlink(fs->super);
+
	group = 0;
	maxgroup = fs->group_desc_count;
	if (ctx->progress)

@@ -249,8 +252,15 @@ void e2fsck_pass4(e2fsck_t ctx)

					    &link_counted);
		}
		isdir = ext2fs_test_inode_bitmap2(ctx->inode_dir_map, i);
-		if (isdir && (link_counted > EXT2_LINK_MAX))
+		if (isdir && (link_counted > EXT2_LINK_MAX)) {
+			if (!dir_nlink_fs &&
+			    fix_problem(ctx, PR_4_DIR_NLINK_FEATURE, &pctx)) {
+				ext2fs_set_feature_dir_nlink(fs->super);
+				ext2fs_mark_super_dirty(fs);
+				dir_nlink_fs = 1;
+			}
			link_counted = 1;
+		}
		if (link_counted != link_count) {
			e2fsck_read_inode_full(ctx, i, EXT2_INODE(inode),
					       inode_size, "pass4");

diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 9706933..25c1de9 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c

@@ -1873,6 +1873,11 @@ static struct e2fsck_problem problem_table[] = {

	  N_("@a @i %i ref count is %N, @s %n. "),
	  PROMPT_FIX, PR_PREEN_OK },

+	/* directory exceeds max links, but no DIR_NLINK feature in superblock*/
+	{ PR_4_DIR_NLINK_FEATURE,
+	  N_("@d exceeds max links, but no DIR_NLINK feature in @S.\n"),
+	  PROMPT_FIX, 0 },
+
	/* Pass 5 errors */

	/* Pass 5: Checking group summary information */

diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index f30f8f0..07ed0a7 100644
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h

@@ -1134,6 +1134,9 @@ struct problem_context {

/* Extended attribute inode ref count wrong */
#define PR_4_EA_INODE_REF_COUNT		0x040005

+/* directory exceeds max links, but no DIR_NLINK feature in superblock */
+#define PR_4_DIR_NLINK_FEATURE		0x040006
+
/*
 * Pass 5 errors
 */

diff --git a/tests/f_large_dir/expect b/tests/f_large_dir/expect
index b099460..4b9ca6f 100644
--- a/tests/f_large_dir/expect
+++ b/tests/f_large_dir/expect

@@ -3,10 +3,13 @@ Pass 2: Checking directory structure

Pass 3: Checking directory connectivity
Pass 3A: Optimizing directories
Pass 4: Checking reference counts
-Inode 13 ref count is 1, should be 47245.  Fix? yes
+Directory exceeds max links, but no DIR_NLINK feature in superblock.
+Fix? yes
+
+Inode 12 ref count is 65012, should be 1.  Fix? yes

Pass 5: Checking group summary information

test.img: ***** FILE SYSTEM WAS MODIFIED *****
-test.img: 13/115368 files (0.0% non-contiguous), 32817/460800 blocks
+test.img: 65023/65104 files (0.0% non-contiguous), 96668/100937 blocks
Exit status is 1

diff --git a/tests/f_large_dir/script b/tests/f_large_dir/script
index 0b5fdff..a10fe16 100644
--- a/tests/f_large_dir/script
+++ b/tests/f_large_dir/script

@@ -5,43 +5,59 @@ E2FSCK=../e2fsck/e2fsck

NAMELEN=255
DIRENT_SZ=8
BLOCKSZ=1024
+INODESZ=128
DIRENT_PER_LEAF=$((BLOCKSZ / (NAMELEN + DIRENT_SZ)))
HEADER=32
INDEX_SZ=8
INDEX_L1=$(((BLOCKSZ - HEADER) / INDEX_SZ))
INDEX_L2=$(((BLOCKSZ - DIRENT_SZ) / INDEX_SZ))
ENTRIES=$((INDEX_L1 * INDEX_L2 * DIRENT_PER_LEAF))
+DIRBLK=$((2 + INDEX_L1 * INDEX_L2))
+EXT4_LINK_MAX=65000
+[ $ENTRIES -lt $((EXT4_LINK_MAX + 10)) ] && ENTRIES=$((EXT4_LINK_MAX + 10))
+FSIZE=$(((DIRBLK + EXT4_LINK_MAX * ((BLOCKSZ + INODESZ) / BLOCKSZ)) * 5 / 4))

-cp /dev/null $OUT
-$MKE2FS -b 1024 -O large_dir,uninit_bg,dir_nlink -F $TMPFILE 460800 \
-	> /dev/null 2>&1
+> $OUT
+$MKE2FS -b 1024 -O large_dir,uninit_bg -N $((ENTRIES + 50)) \
+	-I $INODESZ -F $TMPFILE $FSIZE > $OUT 2>&1
+RC=$?
+if [ $RC -eq 0 ]; then
{
-	echo "feature large_dir"
+	START=$SECONDS
	echo "mkdir /foo"
	echo "cd /foo"
-	touch foofile
-	echo "write foofile foofile"
+	touch $TMPFILE.tmp
+	echo "write $TMPFILE.tmp foofile"
	i=0
-	while test $i  -lt $ENTRIES ; do
-	    if test $(( i % DIRENT_PER_LEAF )) -eq 0 ; then
-		echo "expand ./"
+	while test $i -lt $ENTRIES ; do
+	    if test $((i % DIRENT_PER_LEAF)) -eq 0; then
+	    	echo "expand ./"
	    fi
-	    if test $(( i % 5000 )) -eq 0 -a $i -gt 0 ; then
-		>&2 echo "$test_name: $i processed"
+	    if test $((i % 5000)) -eq 0 -a $i -gt 0; then
+		ELAPSED=$((SECONDS - START))
+		RATE=$((i / ELAPSED))
+		>&2 echo "$test_name: $i processed in ${ELAPSED}s @ $RATE/s"
	    fi
-	    printf "ln foofile %0255X\n" $i
-	    i=$(($i + 1))
+	    if test $i -lt $((EXT4_LINK_MAX + 10)); then
+		printf "mkdir d%0254u\n" $i
+	    else
+		printf "ln foofile f%0254u\n" $i
+	    fi
+	    i=$((i + 1))
	done
-} | $DEBUGFS -w -f /dev/stdin $TMPFILE > /dev/null 2>&1
-
-$E2FSCK -yfD $TMPFILE > $OUT.new 2>&1
-status=$?
-echo Exit status is $status >> $OUT.new
-sed -f $cmd_dir/filter.sed -e "s;$TMPFILE;test.img;" $OUT.new >> $OUT
-rm -f $OUT.new
+} | $DEBUGFS -w -f /dev/stdin $TMPFILE > $OUT
+	RC=$?
+fi
+if [ $RC -eq 0 ]; then
+	$E2FSCK -yfD $TMPFILE > $OUT.new 2>&1
+	status=$?
+	echo "Exit status is $status" >> $OUT.new
+	sed -f $cmd_dir/filter.sed -e "s;$TMPFILE;test.img;" $OUT.new > $OUT
+	rm -f $OUT.new

-cmp -s $OUT $EXP
-RC=$?
+	cmp -s $OUT $EXP
+	RC=$?
+fi
if [ $RC -eq 0 ]; then
	echo "$test_name: $test_description: ok"
	touch $test_name.ok
--
1.8.0