mkfs_ext2: 1.41.9 compat

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/util-linux/mkfs_ext2.c b/util-linux/mkfs_ext2.c
index 7191a5f..ef22ec7 100644 (file)
--- a/util-linux/mkfs_ext2.c
+++ b/util-linux/mkfs_ext2.c
@@ -10,25 +10,19 @@
 #include "libbb.h"
 #include <linux/fs.h>
 #include <linux/ext2_fs.h>
-#include <sys/user.h> /* PAGE_SIZE */
-#ifndef PAGE_SIZE
-# define PAGE_SIZE 4096
-#endif
 #include "volume_id/volume_id_internal.h"
 
 #define        ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT 0
-#define        ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX 1
+#define        ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX    1
 
 // from e2fsprogs
 #define s_reserved_gdt_blocks s_padding1
 #define s_mkfs_time           s_reserved[0]
 #define s_flags               s_reserved[22]
-#define EXT2_HASH_HALF_MD4     1
-#define EXT2_FLAGS_SIGNED_HASH 0x0001
 
-// whiteout: for writable overlays
-//#define LINUX_S_IFWHT                  0160000
-//#define EXT2_FEATURE_INCOMPAT_WHITEOUT 0x0020
+#define EXT2_HASH_HALF_MD4       1
+#define EXT2_FLAGS_SIGNED_HASH   0x0001
+#define EXT2_FLAGS_UNSIGNED_HASH 0x0002
 
 // storage helpers
 char BUG_wrong_field_size(void);
@@ -288,9 +282,6 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
        if (nblocks != kilobytes)
                bb_error_msg_and_die("block count doesn't fit in 32 bits");
 #define kilobytes kilobytes_unused_after_this
-//compat problem
-//     if (blocksize < PAGE_SIZE)
-//             nblocks &= ~((PAGE_SIZE >> blocksize_log2)-1);
        // Experimentally, standard mke2fs won't work on images smaller than 60k
        if (nblocks < 60)
                bb_error_msg_and_die("need >= 60 blocks");
@@ -471,19 +462,22 @@ int mkfs_ext2_main(int argc UNUSED_PARAM, char **argv)
        STORE_LE(sb->s_mkfs_time, timestamp);
        STORE_LE(sb->s_wtime, timestamp);
        STORE_LE(sb->s_lastcheck, timestamp);
-       // misc
+       // misc. Values are chosen to match mke2fs 1.41.9
        STORE_LE(sb->s_state, 1); // TODO: what's 1?
        STORE_LE(sb->s_creator_os, EXT2_OS_LINUX);
        STORE_LE(sb->s_checkinterval, 24*60*60 * 180); // 180 days
        STORE_LE(sb->s_errors, EXT2_ERRORS_DEFAULT);
+       // mke2fs 1.41.9 also sets EXT3_FEATURE_COMPAT_RESIZE_INODE
+       // and if >= 0.5GB, EXT3_FEATURE_RO_COMPAT_LARGE_FILE.
+       // we use values which match "mke2fs -O ^resize_inode":
+       // in this case 1.41.9 never sets EXT3_FEATURE_RO_COMPAT_LARGE_FILE.
        STORE_LE(sb->s_feature_compat, EXT2_FEATURE_COMPAT_SUPP
                | (EXT2_FEATURE_COMPAT_RESIZE_INO * ENABLE_FEATURE_MKFS_EXT2_RESERVED_GDT)
                | (EXT2_FEATURE_COMPAT_DIR_INDEX * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX)
        );
-       // e2fsck from 1.41.9 doesn't like EXT2_FEATURE_INCOMPAT_WHITEOUT
-       STORE_LE(sb->s_feature_incompat, EXT2_FEATURE_INCOMPAT_FILETYPE);// | EXT2_FEATURE_INCOMPAT_WHITEOUT;
+       STORE_LE(sb->s_feature_incompat, EXT2_FEATURE_INCOMPAT_FILETYPE);
        STORE_LE(sb->s_feature_ro_compat, EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER);
-       STORE_LE(sb->s_flags, EXT2_FLAGS_SIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX);
+       STORE_LE(sb->s_flags, EXT2_FLAGS_UNSIGNED_HASH * ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX);
        generate_uuid(sb->s_uuid);
        if (ENABLE_FEATURE_MKFS_EXT2_DIR_INDEX) {
                STORE_LE(sb->s_def_hash_version, EXT2_HASH_HALF_MD4);