diff mbox

[v2,2/4] e2fsprogs: add support for 3-level htree

Message ID 1486977617-17216-3-git-send-email-artem.blagodarenko@gmail.com
State Superseded
Headers show

Commit Message

Artem Blagodarenko Feb. 13, 2017, 9:20 a.m. UTC 
From: Artem Blagodarenko <artem.blagodarenko@seagate.com>

The INCOMPAT_LARGEDIR feature allows larger directories to
be created, both with directory sizes over 2GB and and a
maximum htree depth of 3 instead of the current limit of 2.
These features are needed in order to exceed the currently
limit of approximately 10M entries in a single directory.

debugfs, e2fsck, ext2fs, mke2fs and tune2fs support is
added.

Signed-off-by: Alexey Lyashkov <alexey.lyashkov@seagate.com>
Signed-off-by: Artem Blagodarenko <artem.blagodarenko@seagate.com>
---
 e2fsck/pass1.c       |    5 +++--
 e2fsck/pass2.c       |    5 +++--
 lib/ext2fs/ext2_fs.h |    3 ++-
 lib/ext2fs/ext2fs.h  |   21 ++++++++++++++++++++-
 misc/mke2fs.c        |    3 ++-
 misc/tune2fs.c       |    3 ++-
 6 files changed, 32 insertions(+), 8 deletions(-)

Comments

Andreas Dilger Feb. 14, 2017, 8:10 p.m. UTC | #1 
On Feb 13, 2017, at 2:20 AM, Artem Blagodarenko <artem.blagodarenko@gmail.com> wrote:
> 
> From: Artem Blagodarenko <artem.blagodarenko@seagate.com>
> 
> The INCOMPAT_LARGEDIR feature allows larger directories to
> be created, both with directory sizes over 2GB and and a
> maximum htree depth of 3 instead of the current limit of 2.
> These features are needed in order to exceed the currently
> limit of approximately 10M entries in a single directory.

Note that the ~10M entry limit is for 4KB blocksize.  With 1KB
blocksize the entry limit is more like 100k.

> debugfs, e2fsck, ext2fs, mke2fs and tune2fs support is
> added.
> 
> Signed-off-by: Alexey Lyashkov <alexey.lyashkov@seagate.com>
> Signed-off-by: Artem Blagodarenko <artem.blagodarenko@seagate.com>

Some very minor style fixes and improvement to the commit comment
possible if the patch is resent.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>

> ---
> e2fsck/pass1.c       |    5 +++--
> e2fsck/pass2.c       |    5 +++--
> lib/ext2fs/ext2_fs.h |    3 ++-
> lib/ext2fs/ext2fs.h  |   21 ++++++++++++++++++++-
> misc/mke2fs.c        |    3 ++-
> misc/tune2fs.c       |    3 ++-
> 6 files changed, 32 insertions(+), 8 deletions(-)
> 
> diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
> index ce37176..fff7dcf 100644
> --- a/e2fsck/pass1.c
> +++ b/e2fsck/pass1.c
> @@ -1716,7 +1716,8 @@ void e2fsck_pass1(e2fsck_t ctx)
> 		}
> 
> 		if (inode->i_faddr || frag || fsize ||
> -		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high))
> +		    (!ext2fs_has_feature_large_dir(fs) &&
> +		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high)))
> 			mark_inode_bad(ctx, ino);
> 		if ((fs->super->s_creator_os != EXT2_OS_HURD) &&
> 		    !ext2fs_has_feature_64bit(fs->super) &&
> @@ -2469,7 +2470,7 @@ static int handle_htree(e2fsck_t ctx, struct problem_context *pctx,
> 		return 1;
> 
> 	pctx->num = root->indirect_levels;
> -	if ((root->indirect_levels > 1) &&
> +	if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
> 	    fix_problem(ctx, PR_1_HTREE_DEPTH, pctx))
> 		return 1;
> 
> diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
> index b89ebc9..139d48f 100644
> --- a/e2fsck/pass2.c
> +++ b/e2fsck/pass2.c
> @@ -1058,7 +1058,8 @@ inline_read_fail:
> 			dx_db->flags |= DX_FLAG_FIRST | DX_FLAG_LAST;
> 			if ((root->reserved_zero ||
> 			     root->info_length < 8 ||
> -			     root->indirect_levels > 1) &&
> +			     root->indirect_levels
> +				> ext2_dir_htree_level(fs)) &&

(style) '>' operator at the end of the previous line

> 			    fix_problem(ctx, PR_2_HTREE_BAD_ROOT, &cd->pctx)) {
> 				clear_htree(ctx, ino);
> 				dx_dir->numblocks = 0;
> @@ -1811,7 +1812,7 @@ int e2fsck_process_bad_inode(e2fsck_t ctx, ext2_ino_t dir,
> 		} else
> 			not_fixed++;
> 	}
> -	if (inode.i_size_high &&
> +	if (inode.i_size_high && !ext2fs_has_feature_large_dir(fs) &&
> 	    LINUX_S_ISDIR(inode.i_mode)) {
> 		if (fix_problem(ctx, PR_2_DIR_SIZE_HIGH_ZERO, &pctx)) {
> 			inode.i_size_high = 0;
> diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
> index 195e366..6d9a5d0 100644
> --- a/lib/ext2fs/ext2_fs.h
> +++ b/lib/ext2fs/ext2_fs.h
> @@ -921,7 +921,8 @@ EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		4, ENCRYPT)
> 
> #define EXT2_FEATURE_COMPAT_SUPP	0
> #define EXT2_FEATURE_INCOMPAT_SUPP    (EXT2_FEATURE_INCOMPAT_FILETYPE| \
> -				       EXT4_FEATURE_INCOMPAT_MMP)
> +				       EXT4_FEATURE_INCOMPAT_MMP|\

(style) space before that '\', though I do see it is very inconsistent here

> +				       EXT4_FEATURE_INCOMPAT_LARGEDIR)
> #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
> 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
> 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
> diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
> index 786ded8..d714b44 100644
> --- a/lib/ext2fs/ext2fs.h
> +++ b/lib/ext2fs/ext2fs.h
> @@ -588,7 +588,8 @@ typedef struct ext2_icount *ext2_icount_t;
> 					 EXT4_FEATURE_INCOMPAT_64BIT|\
> 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA|\
> 					 EXT4_FEATURE_INCOMPAT_ENCRYPT|\
> -					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
> +					 EXT4_FEATURE_INCOMPAT_CSUM_SEED|\
> +					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
> 
> #define EXT2_LIB_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|\
> 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE|\
> @@ -1924,6 +1925,24 @@ _INLINE_ blk_t ext2fs_inode_data_blocks(ext2_filsys fs,
> 	return (blk_t) ext2fs_inode_data_blocks2(fs, inode);
> }
> 
> +/* htree levels for ext4 */
> +#define EXT4_HTREE_LEVEL_COMPAT 1
> +#define EXT4_HTREE_LEVEL	3
> +
> +_INLINE_ int ext2fs_has_feature_large_dir(ext2_filsys fs)
> +{
> +	return EXT2_HAS_INCOMPAT_FEATURE(fs->super,
> +					 EXT4_FEATURE_INCOMPAT_LARGEDIR);
> +}
> +
> +_INLINE_ unsigned int ext2_dir_htree_level(ext2_filsys fs)
> +{
> +	if (ext2fs_has_feature_large_dir(fs))
> +		return EXT4_HTREE_LEVEL;
> +
> +	return EXT4_HTREE_LEVEL_COMPAT;
> +}
> +
> /*
>  * This is an efficient, overflow safe way of calculating ceil((1.0 * a) / b)
>  */
> diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> index 9f18c83..b2bf461 100644
> --- a/misc/mke2fs.c
> +++ b/misc/mke2fs.c
> @@ -1081,7 +1081,8 @@ static __u32 ok_features[3] = {
> 		EXT4_FEATURE_INCOMPAT_64BIT|
> 		EXT4_FEATURE_INCOMPAT_INLINE_DATA|
> 		EXT4_FEATURE_INCOMPAT_ENCRYPT |
> -		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
> +		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
> +		EXT4_FEATURE_INCOMPAT_LARGEDIR,
> 	/* R/O compat */
> 	EXT2_FEATURE_RO_COMPAT_LARGE_FILE|
> 		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|
> diff --git a/misc/tune2fs.c b/misc/tune2fs.c
> index 6239577..f78d105 100644
> --- a/misc/tune2fs.c
> +++ b/misc/tune2fs.c
> @@ -156,7 +156,8 @@ static __u32 ok_features[3] = {
> 		EXT4_FEATURE_INCOMPAT_MMP |
> 		EXT4_FEATURE_INCOMPAT_64BIT |
> 		EXT4_FEATURE_INCOMPAT_ENCRYPT |
> -		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
> +		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
> +		EXT4_FEATURE_INCOMPAT_LARGEDIR,
> 	/* R/O compat */
> 	EXT2_FEATURE_RO_COMPAT_LARGE_FILE |
> 		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|
> --
> 1.7.1
> 


Cheers, Andreas
Darrick Wong Feb. 15, 2017, 5:42 a.m. UTC | #2 
On Mon, Feb 13, 2017 at 12:20:15PM +0300, Artem Blagodarenko wrote:
> From: Artem Blagodarenko <artem.blagodarenko@seagate.com>
> 
> The INCOMPAT_LARGEDIR feature allows larger directories to
> be created, both with directory sizes over 2GB and and a
> maximum htree depth of 3 instead of the current limit of 2.
> These features are needed in order to exceed the currently
> limit of approximately 10M entries in a single directory.
> 
> debugfs, e2fsck, ext2fs, mke2fs and tune2fs support is
> added.
> 
> Signed-off-by: Alexey Lyashkov <alexey.lyashkov@seagate.com>
> Signed-off-by: Artem Blagodarenko <artem.blagodarenko@seagate.com>
> ---
>  e2fsck/pass1.c       |    5 +++--
>  e2fsck/pass2.c       |    5 +++--
>  lib/ext2fs/ext2_fs.h |    3 ++-
>  lib/ext2fs/ext2fs.h  |   21 ++++++++++++++++++++-
>  misc/mke2fs.c        |    3 ++-
>  misc/tune2fs.c       |    3 ++-
>  6 files changed, 32 insertions(+), 8 deletions(-)
> 
> diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
> index ce37176..fff7dcf 100644
> --- a/e2fsck/pass1.c
> +++ b/e2fsck/pass1.c
> @@ -1716,7 +1716,8 @@ void e2fsck_pass1(e2fsck_t ctx)
>  		}
>  
>  		if (inode->i_faddr || frag || fsize ||
> -		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high))
> +		    (!ext2fs_has_feature_large_dir(fs) &&
> +		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high)))
>  			mark_inode_bad(ctx, ino);
>  		if ((fs->super->s_creator_os != EXT2_OS_HURD) &&
>  		    !ext2fs_has_feature_64bit(fs->super) &&
> @@ -2469,7 +2470,7 @@ static int handle_htree(e2fsck_t ctx, struct problem_context *pctx,
>  		return 1;
>  
>  	pctx->num = root->indirect_levels;
> -	if ((root->indirect_levels > 1) &&
> +	if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
>  	    fix_problem(ctx, PR_1_HTREE_DEPTH, pctx))
>  		return 1;
>  
> diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
> index b89ebc9..139d48f 100644
> --- a/e2fsck/pass2.c
> +++ b/e2fsck/pass2.c
> @@ -1058,7 +1058,8 @@ inline_read_fail:
>  			dx_db->flags |= DX_FLAG_FIRST | DX_FLAG_LAST;
>  			if ((root->reserved_zero ||
>  			     root->info_length < 8 ||
> -			     root->indirect_levels > 1) &&
> +			     root->indirect_levels
> +				> ext2_dir_htree_level(fs)) &&
>  			    fix_problem(ctx, PR_2_HTREE_BAD_ROOT, &cd->pctx)) {
>  				clear_htree(ctx, ino);
>  				dx_dir->numblocks = 0;
> @@ -1811,7 +1812,7 @@ int e2fsck_process_bad_inode(e2fsck_t ctx, ext2_ino_t dir,
>  		} else
>  			not_fixed++;
>  	}
> -	if (inode.i_size_high &&
> +	if (inode.i_size_high && !ext2fs_has_feature_large_dir(fs) &&
>  	    LINUX_S_ISDIR(inode.i_mode)) {
>  		if (fix_problem(ctx, PR_2_DIR_SIZE_HIGH_ZERO, &pctx)) {
>  			inode.i_size_high = 0;
> diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
> index 195e366..6d9a5d0 100644
> --- a/lib/ext2fs/ext2_fs.h
> +++ b/lib/ext2fs/ext2_fs.h
> @@ -921,7 +921,8 @@ EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		4, ENCRYPT)
>  
>  #define EXT2_FEATURE_COMPAT_SUPP	0
>  #define EXT2_FEATURE_INCOMPAT_SUPP    (EXT2_FEATURE_INCOMPAT_FILETYPE| \
> -				       EXT4_FEATURE_INCOMPAT_MMP)
> +				       EXT4_FEATURE_INCOMPAT_MMP|\
> +				       EXT4_FEATURE_INCOMPAT_LARGEDIR)
>  #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
>  					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
>  					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
> diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
> index 786ded8..d714b44 100644
> --- a/lib/ext2fs/ext2fs.h
> +++ b/lib/ext2fs/ext2fs.h
> @@ -588,7 +588,8 @@ typedef struct ext2_icount *ext2_icount_t;
>  					 EXT4_FEATURE_INCOMPAT_64BIT|\
>  					 EXT4_FEATURE_INCOMPAT_INLINE_DATA|\
>  					 EXT4_FEATURE_INCOMPAT_ENCRYPT|\
> -					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
> +					 EXT4_FEATURE_INCOMPAT_CSUM_SEED|\
> +					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
>  
>  #define EXT2_LIB_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|\
>  					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE|\
> @@ -1924,6 +1925,24 @@ _INLINE_ blk_t ext2fs_inode_data_blocks(ext2_filsys fs,
>  	return (blk_t) ext2fs_inode_data_blocks2(fs, inode);
>  }
>  
> +/* htree levels for ext4 */
> +#define EXT4_HTREE_LEVEL_COMPAT 1
> +#define EXT4_HTREE_LEVEL	3
> +
> +_INLINE_ int ext2fs_has_feature_large_dir(ext2_filsys fs)
> +{
> +	return EXT2_HAS_INCOMPAT_FEATURE(fs->super,
> +					 EXT4_FEATURE_INCOMPAT_LARGEDIR);
> +}

Already provided, see line 955:

EXT4_FEATURE_INCOMPAT_FUNCS(largedir,		4, LARGEDIR)

defines ext2fs_has_feature_largedir().

The rest looks ok.

--D

> +
> +_INLINE_ unsigned int ext2_dir_htree_level(ext2_filsys fs)
> +{
> +	if (ext2fs_has_feature_large_dir(fs))
> +		return EXT4_HTREE_LEVEL;
> +
> +	return EXT4_HTREE_LEVEL_COMPAT;
> +}
> +
>  /*
>   * This is an efficient, overflow safe way of calculating ceil((1.0 * a) / b)
>   */
> diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> index 9f18c83..b2bf461 100644
> --- a/misc/mke2fs.c
> +++ b/misc/mke2fs.c
> @@ -1081,7 +1081,8 @@ static __u32 ok_features[3] = {
>  		EXT4_FEATURE_INCOMPAT_64BIT|
>  		EXT4_FEATURE_INCOMPAT_INLINE_DATA|
>  		EXT4_FEATURE_INCOMPAT_ENCRYPT |
> -		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
> +		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
> +		EXT4_FEATURE_INCOMPAT_LARGEDIR,
>  	/* R/O compat */
>  	EXT2_FEATURE_RO_COMPAT_LARGE_FILE|
>  		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|
> diff --git a/misc/tune2fs.c b/misc/tune2fs.c
> index 6239577..f78d105 100644
> --- a/misc/tune2fs.c
> +++ b/misc/tune2fs.c
> @@ -156,7 +156,8 @@ static __u32 ok_features[3] = {
>  		EXT4_FEATURE_INCOMPAT_MMP |
>  		EXT4_FEATURE_INCOMPAT_64BIT |
>  		EXT4_FEATURE_INCOMPAT_ENCRYPT |
> -		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
> +		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
> +		EXT4_FEATURE_INCOMPAT_LARGEDIR,
>  	/* R/O compat */
>  	EXT2_FEATURE_RO_COMPAT_LARGE_FILE |
>  		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|
> -- 
> 1.7.1
>
diff mbox

Patch

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index ce37176..fff7dcf 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -1716,7 +1716,8 @@  void e2fsck_pass1(e2fsck_t ctx)
 		}
 
 		if (inode->i_faddr || frag || fsize ||
-		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high))
+		    (!ext2fs_has_feature_large_dir(fs) &&
+		    (LINUX_S_ISDIR(inode->i_mode) && inode->i_size_high)))
 			mark_inode_bad(ctx, ino);
 		if ((fs->super->s_creator_os != EXT2_OS_HURD) &&
 		    !ext2fs_has_feature_64bit(fs->super) &&
@@ -2469,7 +2470,7 @@  static int handle_htree(e2fsck_t ctx, struct problem_context *pctx,
 		return 1;
 
 	pctx->num = root->indirect_levels;
-	if ((root->indirect_levels > 1) &&
+	if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
 	    fix_problem(ctx, PR_1_HTREE_DEPTH, pctx))
 		return 1;
 
diff --git a/e2fsck/pass2.c b/e2fsck/pass2.c
index b89ebc9..139d48f 100644
--- a/e2fsck/pass2.c
+++ b/e2fsck/pass2.c
@@ -1058,7 +1058,8 @@  inline_read_fail:
 			dx_db->flags |= DX_FLAG_FIRST | DX_FLAG_LAST;
 			if ((root->reserved_zero ||
 			     root->info_length < 8 ||
-			     root->indirect_levels > 1) &&
+			     root->indirect_levels
+				> ext2_dir_htree_level(fs)) &&
 			    fix_problem(ctx, PR_2_HTREE_BAD_ROOT, &cd->pctx)) {
 				clear_htree(ctx, ino);
 				dx_dir->numblocks = 0;
@@ -1811,7 +1812,7 @@  int e2fsck_process_bad_inode(e2fsck_t ctx, ext2_ino_t dir,
 		} else
 			not_fixed++;
 	}
-	if (inode.i_size_high &&
+	if (inode.i_size_high && !ext2fs_has_feature_large_dir(fs) &&
 	    LINUX_S_ISDIR(inode.i_mode)) {
 		if (fix_problem(ctx, PR_2_DIR_SIZE_HIGH_ZERO, &pctx)) {
 			inode.i_size_high = 0;
diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
index 195e366..6d9a5d0 100644
--- a/lib/ext2fs/ext2_fs.h
+++ b/lib/ext2fs/ext2_fs.h
@@ -921,7 +921,8 @@  EXT4_FEATURE_INCOMPAT_FUNCS(encrypt,		4, ENCRYPT)
 
 #define EXT2_FEATURE_COMPAT_SUPP	0
 #define EXT2_FEATURE_INCOMPAT_SUPP    (EXT2_FEATURE_INCOMPAT_FILETYPE| \
-				       EXT4_FEATURE_INCOMPAT_MMP)
+				       EXT4_FEATURE_INCOMPAT_MMP|\
+				       EXT4_FEATURE_INCOMPAT_LARGEDIR)
 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
 					 EXT4_FEATURE_RO_COMPAT_DIR_NLINK| \
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 786ded8..d714b44 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -588,7 +588,8 @@  typedef struct ext2_icount *ext2_icount_t;
 					 EXT4_FEATURE_INCOMPAT_64BIT|\
 					 EXT4_FEATURE_INCOMPAT_INLINE_DATA|\
 					 EXT4_FEATURE_INCOMPAT_ENCRYPT|\
-					 EXT4_FEATURE_INCOMPAT_CSUM_SEED)
+					 EXT4_FEATURE_INCOMPAT_CSUM_SEED|\
+					 EXT4_FEATURE_INCOMPAT_LARGEDIR)
 
 #define EXT2_LIB_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|\
 					 EXT4_FEATURE_RO_COMPAT_HUGE_FILE|\
@@ -1924,6 +1925,24 @@  _INLINE_ blk_t ext2fs_inode_data_blocks(ext2_filsys fs,
 	return (blk_t) ext2fs_inode_data_blocks2(fs, inode);
 }
 
+/* htree levels for ext4 */
+#define EXT4_HTREE_LEVEL_COMPAT 1
+#define EXT4_HTREE_LEVEL	3
+
+_INLINE_ int ext2fs_has_feature_large_dir(ext2_filsys fs)
+{
+	return EXT2_HAS_INCOMPAT_FEATURE(fs->super,
+					 EXT4_FEATURE_INCOMPAT_LARGEDIR);
+}
+
+_INLINE_ unsigned int ext2_dir_htree_level(ext2_filsys fs)
+{
+	if (ext2fs_has_feature_large_dir(fs))
+		return EXT4_HTREE_LEVEL;
+
+	return EXT4_HTREE_LEVEL_COMPAT;
+}
+
 /*
  * This is an efficient, overflow safe way of calculating ceil((1.0 * a) / b)
  */
diff --git a/misc/mke2fs.c b/misc/mke2fs.c
index 9f18c83..b2bf461 100644
--- a/misc/mke2fs.c
+++ b/misc/mke2fs.c
@@ -1081,7 +1081,8 @@  static __u32 ok_features[3] = {
 		EXT4_FEATURE_INCOMPAT_64BIT|
 		EXT4_FEATURE_INCOMPAT_INLINE_DATA|
 		EXT4_FEATURE_INCOMPAT_ENCRYPT |
-		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
+		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
+		EXT4_FEATURE_INCOMPAT_LARGEDIR,
 	/* R/O compat */
 	EXT2_FEATURE_RO_COMPAT_LARGE_FILE|
 		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|
diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index 6239577..f78d105 100644
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -156,7 +156,8 @@  static __u32 ok_features[3] = {
 		EXT4_FEATURE_INCOMPAT_MMP |
 		EXT4_FEATURE_INCOMPAT_64BIT |
 		EXT4_FEATURE_INCOMPAT_ENCRYPT |
-		EXT4_FEATURE_INCOMPAT_CSUM_SEED,
+		EXT4_FEATURE_INCOMPAT_CSUM_SEED |
+		EXT4_FEATURE_INCOMPAT_LARGEDIR,
 	/* R/O compat */
 	EXT2_FEATURE_RO_COMPAT_LARGE_FILE |
 		EXT4_FEATURE_RO_COMPAT_HUGE_FILE|