(* 'df' command for virtual domains. (C) Copyright 2007 Richard W.M. Jones, Red Hat Inc. http://libvirt.org/ This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. Support for EXT2/EXT3 filesystems. *) open Unix open Printf open Virt_df_gettext.Gettext open Virt_df let superblock_offset = 1024L let probe_ext2 dev = (* Load the superblock. *) let bits = dev#read_bitstring superblock_offset 1024 in (* The structure is straight from /usr/include/linux/ext3_fs.h *) bitmatch bits with | s_inodes_count : 32 : littleendian; (* Inodes count *) s_blocks_count : 32 : littleendian; (* Blocks count *) s_r_blocks_count : 32 : littleendian; (* Reserved blocks count *) s_free_blocks_count : 32 : littleendian; (* Free blocks count *) s_free_inodes_count : 32 : littleendian; (* Free inodes count *) s_first_data_block : 32 : littleendian; (* First Data Block *) s_log_block_size : 32 : littleendian; (* Block size *) s_log_frag_size : 32 : littleendian; (* Fragment size *) s_blocks_per_group : 32 : littleendian; (* # Blocks per group *) s_frags_per_group : 32 : littleendian; (* # Fragments per group *) s_inodes_per_group : 32 : littleendian; (* # Inodes per group *) s_mtime : 32 : littleendian; (* Mount time *) s_wtime : 32 : littleendian; (* Write time *) s_mnt_count : 16 : littleendian; (* Mount count *) s_max_mnt_count : 16 : littleendian; (* Maximal mount count *) 0xef53 : 16 : littleendian; (* Magic signature *) s_state : 16 : littleendian; (* File system state *) s_errors : 16 : littleendian; (* Behaviour when detecting errors *) s_minor_rev_level : 16 : littleendian; (* minor revision level *) s_lastcheck : 32 : littleendian; (* time of last check *) s_checkinterval : 32 : littleendian; (* max. time between checks *) s_creator_os : 32 : littleendian; (* OS *) s_rev_level : 32 : littleendian; (* Revision level *) s_def_resuid : 16 : littleendian; (* Default uid for reserved blocks *) s_def_resgid : 16 : littleendian; (* Default gid for reserved blocks *) s_first_ino : 32 : littleendian; (* First non-reserved inode *) s_inode_size : 16 : littleendian; (* size of inode structure *) s_block_group_nr : 16 : littleendian; (* block group # of this superblock *) s_feature_compat : 32 : littleendian; (* compatible feature set *) s_feature_incompat : 32 : littleendian; (* incompatible feature set *) s_feature_ro_compat : 32 : littleendian; (* readonly-compatible feature set *) s_uuid : 128 : bitstring; (* 128-bit uuid for volume *) s_volume_name : 128 : bitstring; (* volume name XXX string *) s_last_mounted : 512 : bitstring; (* directory where last mounted XXX string *) s_algorithm_usage_bitmap : 32 : littleendian; (* For compression *) s_prealloc_blocks : 8; (* Nr of blocks to try to preallocate*) s_prealloc_dir_blocks : 8; (* Nr to preallocate for dirs *) s_reserved_gdt_blocks : 16 : littleendian; (* Per group desc for online growth *) s_journal_uuid : 128 : bitstring; (* uuid of journal superblock *) s_journal_inum : 32 : littleendian; (* inode number of journal file *) s_journal_dev : 32 : littleendian; (* device number of journal file *) s_last_orphan : 32 : littleendian; (* start of list of inodes to delete *) s_hash_seed0 : 32 : littleendian; (* HTREE hash seed *) s_hash_seed1 : 32 : littleendian; s_hash_seed2 : 32 : littleendian; s_hash_seed3 : 32 : littleendian; s_def_hash_version : 8; (* Default hash version to use *) s_reserved_char_pad : 8; s_reserved_word_pad : 16 : littleendian; s_default_mount_opts : 32 : littleendian; s_first_meta_bg : 32 : littleendian; (* First metablock block group *) s_reserved : 6080 : bitstring -> (* Padding to the end of the block *) (* Work out the block size in bytes. *) let s_log_block_size = Int32.to_int s_log_block_size in let block_size = 1024L in let block_size = Int64.shift_left block_size s_log_block_size in (* Number of groups. *) let s_groups_count = Int64.of_int32 ( (s_blocks_count -* s_first_data_block -* 1l) /* s_blocks_per_group +* 1l ) in (* (* Number of group descriptors per block. *) let s_inodes_per_block = s_blocksize / let s_desc_per_block = block_size / s_inodes_per_block in let db_count = (s_groups_count +^ s_desc_per_block -^ 1L) /^ s_desc_per_block *) (* Calculate the block overhead (used by superblocks, inodes, etc.) * See fs/ext2/super.c. *) let overhead = Int64.of_int32 s_first_data_block in let overhead = (* XXX *) overhead in { fs_name = s_ "Linux ext2/3"; fs_block_size = block_size; fs_blocks_total = Int64.of_int32 s_blocks_count -^ overhead; fs_is_swap = false; fs_blocks_reserved = Int64.of_int32 s_r_blocks_count; fs_blocks_avail = Int64.of_int32 s_free_blocks_count; fs_blocks_used = Int64.of_int32 s_blocks_count -^ overhead -^ Int64.of_int32 s_free_blocks_count; fs_inodes_total = Int64.of_int32 s_inodes_count; fs_inodes_reserved = 0L; (* XXX? *) fs_inodes_avail = Int64.of_int32 s_free_inodes_count; fs_inodes_used = Int64.of_int32 s_inodes_count (*-^ 0L*) -^ Int64.of_int32 s_free_inodes_count; } | _ -> raise Not_found (* Not an EXT2/3 superblock. *) (* Register with main code. *) let () = filesystem_type_register "ext2" probe_ext2