On-disk format definition for 64-bit support

- EXT4_FEATURE_INCOMPAT_64BIT (0x0080) - support for 64-bit block count
  fields in the superblock (s_blocks_count_hi, s_free_blocks_count_hi),
  large group descriptors (s_desc_size), extents with high 16 bits
  (ee_start_hi, ei_leaf_hi), inode ACL (i_file_acl_hi).  May also grow
  to encompass the previously proposed BIG_BG.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/lib/ext2fs/ChangeLog b/lib/ext2fs/ChangeLog
index 58d54bc..dedd6b9 100644 (file)
--- a/lib/ext2fs/ChangeLog
+++ b/lib/ext2fs/ChangeLog
@@ -1,5 +1,12 @@
 2006-11-11  Theodore Tso  <tytso@mit.edu>
 
+       * swapfs.c (ext2fs_swap_super): 
+         ext2_fs.h: Add definition of EXT4_FEATURE_INCOMPAT_64BIT, 
+                 which adds supports for 64-bit block count fields in the 
+                 superblock (s_blocks_count_hi, s_free_blocks_count_hi),
+                 large group descriptors (s_desc_size), extents with high 
+                 16 bits (ee_start_hi, ei_leaf_hi), inode ACL (i_file_acl_hi)
+
        * ext2_fs.h: Add definition of EXT4_FEATURE_RO_COMPAT_DIR_NLINK,
                which allow directories to have > 65000 subdirectories
                (i_nlinks) by setting i_nlinks = 1 for such directories.

diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
index f9c0199..f3c27ab 100644 (file)
--- a/lib/ext2fs/ext2_fs.h
+++ b/lib/ext2fs/ext2_fs.h
@@ -137,8 +137,8 @@ struct ext2_acl_entry       /* Access Control List Entry */
  */
 struct ext2_group_desc
 {
-       __u32   bg_block_bitmap;                /* Blocks bitmap block */
-       __u32   bg_inode_bitmap;                /* Inodes bitmap block */
+       __u32   bg_block_bitmap;        /* Blocks bitmap block */
+       __u32   bg_inode_bitmap;        /* Inodes bitmap block */
        __u32   bg_inode_table;         /* Inodes table block */
        __u16   bg_free_blocks_count;   /* Free blocks count */
        __u16   bg_free_inodes_count;   /* Free inodes count */
@@ -149,6 +149,27 @@ struct ext2_group_desc
        __u16   bg_checksum;            /* crc16(s_uuid+grouo_num+group_desc)*/
 };
 
+struct ext4_group_desc
+{
+       __u32   bg_block_bitmap;        /* Blocks bitmap block */
+       __u32   bg_inode_bitmap;        /* Inodes bitmap block */
+       __u32   bg_inode_table;         /* Inodes table block */
+       __u16   bg_free_blocks_count;   /* Free blocks count */
+       __u16   bg_free_inodes_count;   /* Free inodes count */
+       __u16   bg_used_dirs_count;     /* Directories count */
+       __u16   bg_flags;
+       __u32   bg_reserved[2];
+       __u16   bg_itable_unused;       /* Unused inodes count */
+       __u16   bg_checksum;            /* crc16(s_uuid+grouo_num+group_desc)*/
+       __u32   bg_block_bitmap_hi;     /* Blocks bitmap block MSB */
+       __u32   bg_inode_bitmap_hi;     /* Inodes bitmap block MSB */
+       __u32   bg_inode_table_hi;      /* Inodes table block MSB */
+       __u16   bg_free_blocks_count_hi;/* Free blocks count MSB */
+       __u16   bg_free_inodes_count_hi;/* Free inodes count MSB */
+       __u16   bg_used_dirs_count_hi;  /* Directories count MSB */
+       __u32   bg_reserved2[3];
+};
+
 #define EXT2_BG_INODE_UNINIT   0x0001 /* Inode table/bitmap not initialized */
 #define EXT2_BG_BLOCK_UNINIT   0x0002 /* Block bitmap not initialized */
 
@@ -521,12 +542,15 @@ struct ext2_super_block {
        __u32   s_hash_seed[4];         /* HTREE hash seed */
        __u8    s_def_hash_version;     /* Default hash version to use */
        __u8    s_jnl_backup_type;      /* Default type of journal backup */
-       __u16   s_reserved_word_pad;
+       __u16   s_desc_size;            /* Group desc. size: INCOMPAT_64BIT */
        __u32   s_default_mount_opts;
        __u32   s_first_meta_bg;        /* First metablock group */
        __u32   s_mkfs_time;            /* When the filesystem was created */
        __u32   s_jnl_blocks[17];       /* Backup of the journal inode */
-       __u32   s_reserved[172];        /* Padding to the end of the block */
+       __u32   s_blocks_count_hi;      /* Blocks count high 32bits */
+       __u32   s_r_blocks_count_hi;    /* Reserved blocks count high 32 bits*/
+       __u32   s_free_blocks_hi;       /* Free blocks count */
+       __u32   s_reserved[169];        /* Padding to the end of the block */
 };
 
 /*
@@ -586,6 +610,7 @@ struct ext2_super_block {
 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV      0x0008 /* Journal device */
 #define EXT2_FEATURE_INCOMPAT_META_BG          0x0010
 #define EXT3_FEATURE_INCOMPAT_EXTENTS          0x0040
+#define EXT4_FEATURE_INCOMPAT_64BIT            0x0080
 
 
 #define EXT2_FEATURE_COMPAT_SUPP       0

diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c
index b18bb4a..f332e87 100644 (file)
--- a/lib/ext2fs/swapfs.c
+++ b/lib/ext2fs/swapfs.c
@@ -60,6 +60,7 @@ void ext2fs_swap_super(struct ext2_super_block * sb)
        sb->s_journal_inum = ext2fs_swab32(sb->s_journal_inum);
        sb->s_journal_dev = ext2fs_swab32(sb->s_journal_dev);
        sb->s_last_orphan = ext2fs_swab32(sb->s_last_orphan);
+       sb->s_desc_size = ext2fs_swab16(sb->s_desc_size);
        sb->s_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts);
        sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg);
        sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time);