From: "Theodore Ts'o" Subject: [PATCH, E2FSPROGS] On-disk format for large number of subdirectors Date: Wed, 18 Oct 2006 02:24:01 -0400 Message-ID: Return-path: Received: from thunk.org ([69.25.196.29]:451 "EHLO thunker.thunk.org") by vger.kernel.org with ESMTP id S1751453AbWJRGYF (ORCPT ); Wed, 18 Oct 2006 02:24:05 -0400 To: linux-ext4@vger.kernel.org Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Comments? - Ted On-disk format for large number of subdirectories - EXT4_FEATURE_RO_COMPAT_DIR_NLINK (0x0020?) - allow directories to have > 65000 subdirectories (i_nlinks) by setting i_nlinks = 1 for such directories. RO_COMPAT protects old filesystems from unlinking such directories incorrectly and losing all files therein. Signed-off-by: "Theodore Ts'o" Index: e2fsprogs/lib/ext2fs/ext2_fs.h =================================================================== --- e2fsprogs.orig/lib/ext2fs/ext2_fs.h 2006-10-18 01:42:48.000000000 -0400 +++ e2fsprogs/lib/ext2fs/ext2_fs.h 2006-10-18 01:49:51.000000000 -0400 @@ -71,7 +71,7 @@ /* * Maximal count of links to a file */ -#define EXT2_LINK_MAX 32000 +#define EXT2_LINK_MAX 65000 /* * Macro-instructions used to manage several block sizes @@ -606,6 +606,7 @@ /* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004 not used */ #define EXT4_FEATURE_RO_COMPAT_HUGE_FILE 0x0008 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010 +#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK 0x0020 #define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001 #define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002