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769 lines
24 KiB
769 lines
24 KiB
/* mke2fs.c - Create an ext2 filesystem image.
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*
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* Copyright 2006, 2007 Rob Landley <rob@landley.net>
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// Still to go: "E:jJ:L:m:O:"
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USE_MKE2FS(NEWTOY(mke2fs, "<1>2g:Fnqm#N#i#b#", TOYFLAG_SBIN))
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config MKE2FS
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bool "mke2fs"
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default n
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help
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usage: mke2fs [-Fnq] [-b ###] [-N|i ###] [-m ###] device
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Create an ext2 filesystem on a block device or filesystem image.
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-F Force to run on a mounted device
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-n Don't write to device
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-q Quiet (no output)
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-b size Block size (1024, 2048, or 4096)
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-N inodes Allocate this many inodes
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-i bytes Allocate one inode for every XXX bytes of device
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-m percent Reserve this percent of filesystem space for root user
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config MKE2FS_JOURNAL
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bool "Journaling support (ext3)"
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default n
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depends on MKE2FS
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help
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usage: mke2fs [-j] [-J size=###,device=XXX]
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-j Create journal (ext3)
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-J Journal options
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size: Number of blocks (1024-102400)
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device: Specify an external journal
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config MKE2FS_GEN
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bool "Generate (gene2fs)"
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default n
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depends on MKE2FS
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help
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usage: gene2fs [options] device filename
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The [options] are the same as mke2fs.
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config MKE2FS_LABEL
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bool "Label support"
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default n
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depends on MKE2FS
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help
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usage: mke2fs [-L label] [-M path] [-o string]
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-L Volume label
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-M Path to mount point
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-o Created by
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config MKE2FS_EXTENDED
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bool "Extended options"
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default n
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depends on MKE2FS
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help
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usage: mke2fs [-E stride=###] [-O option[,option]]
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-E stride= Set RAID stripe size (in blocks)
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-O [opts] Specify fewer ext2 option flags (for old kernels)
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All of these are on by default (as appropriate)
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none Clear default options (all but journaling)
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dir_index Use htree indexes for large directories
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filetype Store file type info in directory entry
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has_journal Set by -j
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journal_dev Set by -J device=XXX
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sparse_super Don't allocate huge numbers of redundant superblocks
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*/
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#define FOR_mke2fs
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#include "toys.h"
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GLOBALS(
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// Command line arguments.
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long blocksize;
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long bytes_per_inode;
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long inodes; // Total inodes in filesystem.
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long reserved_percent; // Integer precent of space to reserve for root.
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char *gendir; // Where to read dirtree from.
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// Internal data.
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struct dirtree *dt; // Tree of files to copy into the new filesystem.
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unsigned treeblocks; // Blocks used by dt
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unsigned treeinodes; // Inodes used by dt
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unsigned blocks; // Total blocks in the filesystem.
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unsigned freeblocks; // Free blocks in the filesystem.
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unsigned inodespg; // Inodes per group
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unsigned groups; // Total number of block groups.
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unsigned blockbits; // Bits per block. (Also blocks per group.)
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// For gene2fs
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unsigned nextblock; // Next data block to allocate
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unsigned nextgroup; // Next group we'll be allocating from
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int fsfd; // File descriptor of filesystem (to output to).
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)
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// Stuff defined in linux/ext2_fs.h
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#define EXT2_SUPER_MAGIC 0xEF53
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struct ext2_superblock {
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uint32_t inodes_count; // Inodes count
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uint32_t blocks_count; // Blocks count
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uint32_t r_blocks_count; // Reserved blocks count
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uint32_t free_blocks_count; // Free blocks count
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uint32_t free_inodes_count; // Free inodes count
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uint32_t first_data_block; // First Data Block
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uint32_t log_block_size; // Block size
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uint32_t log_frag_size; // Fragment size
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uint32_t blocks_per_group; // Blocks per group
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uint32_t frags_per_group; // Fragments per group
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uint32_t inodes_per_group; // Inodes per group
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uint32_t mtime; // Mount time
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uint32_t wtime; // Write time
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uint16_t mnt_count; // Mount count
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uint16_t max_mnt_count; // Maximal mount count
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uint16_t magic; // Magic signature
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uint16_t state; // File system state
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uint16_t errors; // Behaviour when detecting errors
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uint16_t minor_rev_level; // minor revision level
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uint32_t lastcheck; // time of last check
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uint32_t checkinterval; // max. time between checks
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uint32_t creator_os; // OS
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uint32_t rev_level; // Revision level
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uint16_t def_resuid; // Default uid for reserved blocks
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uint16_t def_resgid; // Default gid for reserved blocks
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uint32_t first_ino; // First non-reserved inode
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uint16_t inode_size; // size of inode structure
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uint16_t block_group_nr; // block group # of this superblock
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uint32_t feature_compat; // compatible feature set
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uint32_t feature_incompat; // incompatible feature set
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uint32_t feature_ro_compat; // readonly-compatible feature set
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char uuid[16]; // 128-bit uuid for volume
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char volume_name[16]; // volume name
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char last_mounted[64]; // directory where last mounted
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uint32_t alg_usage_bitmap; // For compression
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// For EXT2_COMPAT_PREALLOC
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uint8_t prealloc_blocks; // Nr of blocks to try to preallocate
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uint8_t prealloc_dir_blocks; //Nr to preallocate for dirs
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uint16_t padding1;
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// For EXT3_FEATURE_COMPAT_HAS_JOURNAL
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uint8_t journal_uuid[16]; // uuid of journal superblock
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uint32_t journal_inum; // inode number of journal file
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uint32_t journal_dev; // device number of journal file
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uint32_t last_orphan; // start of list of inodes to delete
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uint32_t hash_seed[4]; // HTREE hash seed
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uint8_t def_hash_version; // Default hash version to use
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uint8_t padding2[3];
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uint32_t default_mount_opts;
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uint32_t first_meta_bg; // First metablock block group
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uint32_t mkfs_time; // Creation timestamp
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uint32_t jnl_blocks[17]; // Backup of journal inode
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// uint32_t reserved[172]; // Padding to the end of the block
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};
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struct ext2_group
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{
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uint32_t block_bitmap; // Block number of block bitmap
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uint32_t inode_bitmap; // Block number of inode bitmap
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uint32_t inode_table; // Block number of inode table
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uint16_t free_blocks_count; // How many free blocks in this group?
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uint16_t free_inodes_count; // How many free inodes in this group?
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uint16_t used_dirs_count; // How many directories?
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uint16_t reserved[7]; // pad to 32 bytes
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};
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struct ext2_dentry {
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uint32_t inode; // Inode number
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uint16_t rec_len; // Directory entry length
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uint8_t name_len; // Name length
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uint8_t file_type;
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char name[0]; // File name
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};
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struct ext2_inode {
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uint16_t mode; // File mode
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uint16_t uid; // Low 16 bits of Owner Uid
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uint32_t size; // Size in bytes
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uint32_t atime; // Access time
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uint32_t ctime; // Creation time
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uint32_t mtime; // Modification time
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uint32_t dtime; // Deletion Time
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uint16_t gid; // Low 16 bits of Group Id
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uint16_t links_count; // Links count
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uint32_t blocks; // Blocks count
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uint32_t flags; // File flags
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uint32_t reserved1;
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uint32_t block[15]; // Pointers to blocks
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uint32_t generation; // File version (for NFS)
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uint32_t file_acl; // File ACL
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uint32_t dir_acl; // Directory ACL (or top bits of file length)
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uint32_t faddr; // Last block in file
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uint8_t frag; // Fragment number
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uint8_t fsize; // Fragment size
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uint16_t pad1;
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uint16_t uid_high; // High bits of uid
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uint16_t gid_high; // High bits of gid
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uint32_t reserved2;
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};
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#define EXT2_FEATURE_COMPAT_DIR_PREALLOC 0x0001
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#define EXT2_FEATURE_COMPAT_IMAGIC_INODES 0x0002
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#define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x0004
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#define EXT2_FEATURE_COMPAT_EXT_ATTR 0x0008
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#define EXT2_FEATURE_COMPAT_RESIZE_INO 0x0010
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#define EXT2_FEATURE_COMPAT_DIR_INDEX 0x0020
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#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER 0x0001
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#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE 0x0002
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#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR 0x0004
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#define EXT2_FEATURE_INCOMPAT_COMPRESSION 0x0001
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#define EXT2_FEATURE_INCOMPAT_FILETYPE 0x0002
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#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004
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#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x0008
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#define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
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#define EXT2_NAME_LEN 255
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// Ext2 directory file types. Only the low 3 bits are used. The
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// other bits are reserved for now.
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enum {
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EXT2_FT_UNKNOWN,
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EXT2_FT_REG_FILE,
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EXT2_FT_DIR,
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EXT2_FT_CHRDEV,
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EXT2_FT_BLKDEV,
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EXT2_FT_FIFO,
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EXT2_FT_SOCK,
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EXT2_FT_SYMLINK,
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EXT2_FT_MAX
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};
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#define INODES_RESERVED 10
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static uint32_t div_round_up(uint32_t a, uint32_t b)
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{
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uint32_t c = a/b;
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if (a%b) c++;
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return c;
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}
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// Calculate data blocks plus index blocks needed to hold a file.
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static uint32_t file_blocks_used(uint64_t size, uint32_t *blocklist)
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{
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uint32_t dblocks = (uint32_t)((size+(TT.blocksize-1))/TT.blocksize);
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uint32_t idx=TT.blocksize/4, iblocks=0, diblocks=0, tiblocks=0;
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// Fill out index blocks in inode.
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if (blocklist) {
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int i;
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// Direct index blocks
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for (i=0; i<13 && i<dblocks; i++) blocklist[i] = i;
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// Singly indirect index blocks
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if (dblocks > 13+idx) blocklist[13] = 13+idx;
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// Doubly indirect index blocks
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idx = 13 + idx + (idx*idx);
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if (dblocks > idx) blocklist[14] = idx;
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return 0;
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}
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// Account for direct, singly, doubly, and triply indirect index blocks
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if (dblocks > 12) {
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iblocks = ((dblocks-13)/idx)+1;
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if (iblocks > 1) {
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diblocks = ((iblocks-2)/idx)+1;
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if (diblocks > 1)
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tiblocks = ((diblocks-2)/idx)+1;
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}
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}
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return dblocks + iblocks + diblocks + tiblocks;
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}
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// Use the parent pointer to iterate through the tree non-recursively.
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static struct dirtree *treenext(struct dirtree *this)
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{
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while (this && !this->next) this = this->parent;
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if (this) this = this->next;
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return this;
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}
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// Recursively calculate the number of blocks used by each inode in the tree.
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// Returns blocks used by this directory, assigns bytes used to *size.
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// Writes total block count to TT.treeblocks and inode count to TT.treeinodes.
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static long check_treesize(struct dirtree *that, off_t *size)
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{
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long blocks;
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while (that) {
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*size += sizeof(struct ext2_dentry) + strlen(that->name);
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if (that->child)
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that->st.st_blocks = check_treesize(that->child, &that->st.st_size);
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else if (S_ISREG(that->st.st_mode)) {
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that->st.st_blocks = file_blocks_used(that->st.st_size, 0);
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TT.treeblocks += that->st.st_blocks;
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}
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that = that->next;
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}
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TT.treeblocks += blocks = file_blocks_used(*size, 0);
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TT.treeinodes++;
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return blocks;
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}
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// Calculate inode numbers and link counts.
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//
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// To do this right I need to copy the tree and sort it, but here's a really
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// ugly n^2 way of dealing with the problem that doesn't scale well to large
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// numbers of files (> 100,000) but can be done in very little code.
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// This rewrites inode numbers to their final values, allocating depth first.
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static void check_treelinks(struct dirtree *tree)
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{
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struct dirtree *current=tree, *that;
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long inode = INODES_RESERVED;
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while (current) {
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++inode;
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// Since we can't hardlink to directories, we know their link count.
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if (S_ISDIR(current->st.st_mode)) current->st.st_nlink = 2;
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else {
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dev_t new = current->st.st_dev;
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if (!new) continue;
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// Look for other copies of current node
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current->st.st_nlink = 0;
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for (that = tree; that; that = treenext(that)) {
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if (current->st.st_ino == that->st.st_ino &&
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current->st.st_dev == that->st.st_dev)
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{
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current->st.st_nlink++;
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current->st.st_ino = inode;
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}
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}
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}
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current->st.st_ino = inode;
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current = treenext(current);
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}
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}
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// Calculate inodes per group from total inodes.
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static uint32_t get_inodespg(uint32_t inodes)
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{
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uint32_t temp;
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// Round up to fill complete inode blocks.
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temp = (inodes + TT.groups - 1) / TT.groups;
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inodes = TT.blocksize/sizeof(struct ext2_inode);
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return ((temp + inodes - 1)/inodes)*inodes;
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}
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// Fill out superblock and TT structures.
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static void init_superblock(struct ext2_superblock *sb)
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{
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uint32_t temp;
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// Set log_block_size and log_frag_size.
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for (temp = 0; temp < 4; temp++) if (TT.blocksize == 1024<<temp) break;
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if (temp==4) error_exit("bad blocksize");
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sb->log_block_size = sb->log_frag_size = SWAP_LE32(temp);
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// Fill out blocks_count, r_blocks_count, first_data_block
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sb->blocks_count = SWAP_LE32(TT.blocks);
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sb->free_blocks_count = SWAP_LE32(TT.freeblocks);
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temp = (TT.blocks * (uint64_t)TT.reserved_percent) / 100;
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sb->r_blocks_count = SWAP_LE32(temp);
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sb->first_data_block = SWAP_LE32(TT.blocksize == 1024 ? 1 : 0);
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// Set blocks_per_group and frags_per_group, which is the size of an
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// allocation bitmap that fits in one block (I.E. how many bits per block)?
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sb->blocks_per_group = sb->frags_per_group = SWAP_LE32(TT.blockbits);
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// Set inodes_per_group and total inodes_count
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sb->inodes_per_group = SWAP_LE32(TT.inodespg);
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sb->inodes_count = SWAP_LE32(TT.inodespg * TT.groups);
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// Determine free inodes.
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temp = TT.inodespg*TT.groups - INODES_RESERVED;
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if (temp < TT.treeinodes) error_exit("Not enough inodes.\n");
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sb->free_inodes_count = SWAP_LE32(temp - TT.treeinodes);
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// Fill out the rest of the superblock.
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sb->max_mnt_count=0xFFFF;
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sb->wtime = sb->lastcheck = sb->mkfs_time = SWAP_LE32(time(NULL));
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sb->magic = SWAP_LE32(0xEF53);
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sb->state = sb->errors = SWAP_LE16(1);
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sb->rev_level = SWAP_LE32(1);
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sb->first_ino = SWAP_LE32(INODES_RESERVED+1);
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sb->inode_size = SWAP_LE16(sizeof(struct ext2_inode));
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sb->feature_incompat = SWAP_LE32(EXT2_FEATURE_INCOMPAT_FILETYPE);
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sb->feature_ro_compat = SWAP_LE32(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER);
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create_uuid(sb->uuid);
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// TODO If we're called as mke3fs or mkfs.ext3, do a journal.
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//if (strchr(toys.which->name,'3'))
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// sb->feature_compat |= SWAP_LE32(EXT3_FEATURE_COMPAT_HAS_JOURNAL);
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}
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// Does this group contain a superblock backup (and group descriptor table)?
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static int is_sb_group(uint32_t group)
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{
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int i;
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// Superblock backups are on groups 0, 1, and powers of 3, 5, and 7.
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if(!group || group==1) return 1;
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for (i=3; i<9; i+=2) {
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int j = i;
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while (j<group) j*=i;
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if (j==group) return 1;
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}
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return 0;
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}
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// Number of blocks used in group by optional superblock/group list backup.
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static int group_superblock_overhead(uint32_t group)
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{
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int used;
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if (!is_sb_group(group)) return 0;
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// How many blocks does the group descriptor table take up?
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used = TT.groups * sizeof(struct ext2_group);
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used += TT.blocksize - 1;
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used /= TT.blocksize;
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// Plus the superblock itself.
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used++;
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// And a corner case.
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if (!group && TT.blocksize == 1024) used++;
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return used;
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}
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// Number of blocks used in group to store superblock/group/inode list
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static int group_overhead(uint32_t group)
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{
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// Return superblock backup overhead (if any), plus block/inode
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// allocation bitmaps, plus inode tables.
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return group_superblock_overhead(group) + 2 + get_inodespg(TT.inodespg)
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/ (TT.blocksize/sizeof(struct ext2_inode));
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}
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// In bitmap "array" set "len" bits starting at position "start" (from 0).
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static void bits_set(char *array, int start, int len)
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{
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while(len) {
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if ((start&7) || len<8) {
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array[start/8]|=(1<<(start&7));
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start++;
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len--;
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} else {
|
|
array[start/8]=255;
|
|
start+=8;
|
|
len-=8;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Seek past len bytes (to maintain sparse file), or write zeroes if output
|
|
// not seekable
|
|
static void put_zeroes(int len)
|
|
{
|
|
if(-1 == lseek(TT.fsfd, len, SEEK_SET)) {
|
|
memset(toybuf, 0, sizeof(toybuf));
|
|
while (len) {
|
|
int out = len > sizeof(toybuf) ? sizeof(toybuf) : len;
|
|
xwrite(TT.fsfd, toybuf, out);
|
|
len -= out;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Fill out an inode structure from struct stat info in dirtree.
|
|
static void fill_inode(struct ext2_inode *in, struct dirtree *that)
|
|
{
|
|
uint32_t fbu[15];
|
|
int temp;
|
|
|
|
file_blocks_used(that->st.st_size, fbu);
|
|
|
|
// If that inode needs data blocks allocated to it.
|
|
if (that->st.st_size) {
|
|
int i, group = TT.nextblock/TT.blockbits;
|
|
|
|
// TODO: teach this about indirect blocks.
|
|
for (i=0; i<15; i++) {
|
|
// If we just jumped into a new group, skip group overhead blocks.
|
|
while (group >= TT.nextgroup)
|
|
TT.nextblock += group_overhead(TT.nextgroup++);
|
|
}
|
|
}
|
|
// TODO : S_ISREG/DIR/CHR/BLK/FIFO/LNK/SOCK(m)
|
|
in->mode = SWAP_LE32(that->st.st_mode);
|
|
|
|
in->uid = SWAP_LE16(that->st.st_uid & 0xFFFF);
|
|
in->uid_high = SWAP_LE16(that->st.st_uid >> 16);
|
|
in->gid = SWAP_LE16(that->st.st_gid & 0xFFFF);
|
|
in->gid_high = SWAP_LE16(that->st.st_gid >> 16);
|
|
in->size = SWAP_LE32(that->st.st_size & 0xFFFFFFFF);
|
|
|
|
// Contortions to make the compiler not generate a warning for x>>32
|
|
// when x is 32 bits. The optimizer should clean this up.
|
|
if (sizeof(that->st.st_size) > 4) temp = 32;
|
|
else temp = 0;
|
|
if (temp) in->dir_acl = SWAP_LE32(that->st.st_size >> temp);
|
|
|
|
in->atime = SWAP_LE32(that->st.st_atime);
|
|
in->ctime = SWAP_LE32(that->st.st_ctime);
|
|
in->mtime = SWAP_LE32(that->st.st_mtime);
|
|
|
|
in->links_count = SWAP_LE16(that->st.st_nlink);
|
|
in->blocks = SWAP_LE32(that->st.st_blocks);
|
|
// in->faddr
|
|
}
|
|
|
|
// Works like an archiver.
|
|
// The first argument is the name of the file to create. If it already
|
|
// exists, that size will be used.
|
|
|
|
void mke2fs_main(void)
|
|
{
|
|
int i, temp;
|
|
off_t length;
|
|
uint32_t usedblocks, usedinodes, dtbblk;
|
|
struct dirtree *dti, *dtb;
|
|
struct ext2_superblock sb;
|
|
|
|
// Handle command line arguments.
|
|
|
|
if (toys.optargs[1]) {
|
|
sscanf(toys.optargs[1], "%u", &TT.blocks);
|
|
temp = O_RDWR|O_CREAT;
|
|
} else temp = O_RDWR;
|
|
if (!TT.reserved_percent) TT.reserved_percent = 5;
|
|
|
|
// TODO: Check if filesystem is mounted here
|
|
|
|
// For mke?fs, open file. For gene?fs, create file.
|
|
TT.fsfd = xcreate(*toys.optargs, temp, 0777);
|
|
|
|
// Determine appropriate block size and block count from file length.
|
|
// (If no length, default to 4k. They can override it on the cmdline.)
|
|
|
|
length = fdlength(TT.fsfd);
|
|
if (!TT.blocksize) TT.blocksize = (length && length < 1<<29) ? 1024 : 4096;
|
|
TT.blockbits = 8*TT.blocksize;
|
|
if (!TT.blocks) TT.blocks = length/TT.blocksize;
|
|
|
|
// Collect gene2fs list or lost+found, calculate requirements.
|
|
|
|
if (TT.gendir) {
|
|
strncpy(toybuf, TT.gendir, sizeof(toybuf));
|
|
dti = dirtree_read(toybuf, dirtree_notdotdot);
|
|
} else {
|
|
dti = xzalloc(sizeof(struct dirtree)+11);
|
|
strcpy(dti->name, "lost+found");
|
|
dti->st.st_mode = S_IFDIR|0755;
|
|
dti->st.st_ctime = dti->st.st_mtime = time(NULL);
|
|
}
|
|
|
|
// Add root directory inode. This is iterated through for when finding
|
|
// blocks, but not when finding inodes. The tree's parent pointers don't
|
|
// point back into this.
|
|
|
|
dtb = xzalloc(sizeof(struct dirtree)+1);
|
|
dtb->st.st_mode = S_IFDIR|0755;
|
|
dtb->st.st_ctime = dtb->st.st_mtime = time(NULL);
|
|
dtb->child = dti;
|
|
|
|
// Figure out how much space is used by preset files
|
|
length = check_treesize(dtb, &(dtb->st.st_size));
|
|
check_treelinks(dtb);
|
|
|
|
// Figure out how many total inodes we need.
|
|
|
|
if (!TT.inodes) {
|
|
if (!TT.bytes_per_inode) TT.bytes_per_inode = 8192;
|
|
TT.inodes = (TT.blocks * (uint64_t)TT.blocksize) / TT.bytes_per_inode;
|
|
}
|
|
|
|
// If we're generating a filesystem and have no idea how many blocks it
|
|
// needs, start with a minimal guess, find the overhead of that many
|
|
// groups, and loop until this is enough groups to store this many blocks.
|
|
if (!TT.blocks) TT.groups = (TT.treeblocks/TT.blockbits)+1;
|
|
else TT.groups = div_round_up(TT.blocks, TT.blockbits);
|
|
|
|
for (;;) {
|
|
temp = TT.treeblocks;
|
|
|
|
for (i = 0; i<TT.groups; i++) temp += group_overhead(i);
|
|
|
|
if (TT.blocks) {
|
|
if (TT.blocks < temp) error_exit("Not enough space.\n");
|
|
break;
|
|
}
|
|
if (temp <= TT.groups * TT.blockbits) {
|
|
TT.blocks = temp;
|
|
break;
|
|
}
|
|
TT.groups++;
|
|
}
|
|
TT.freeblocks = TT.blocks - temp;
|
|
|
|
// Now we know all the TT data, initialize superblock structure.
|
|
|
|
init_superblock(&sb);
|
|
|
|
// Start writing. Skip the first 1k to avoid the boot sector (if any).
|
|
put_zeroes(1024);
|
|
|
|
// Loop through block groups, write out each one.
|
|
dtbblk = usedblocks = usedinodes = 0;
|
|
for (i=0; i<TT.groups; i++) {
|
|
struct ext2_inode *in = (struct ext2_inode *)toybuf;
|
|
uint32_t start, itable, used, end;
|
|
int j, slot;
|
|
|
|
// Where does this group end?
|
|
end = TT.blockbits;
|
|
if ((i+1)*TT.blockbits > TT.blocks) end = TT.blocks & (TT.blockbits-1);
|
|
|
|
// Blocks used by inode table
|
|
itable = (TT.inodespg*sizeof(struct ext2_inode))/TT.blocksize;
|
|
|
|
// If a superblock goes here, write it out.
|
|
start = group_superblock_overhead(i);
|
|
if (start) {
|
|
struct ext2_group *bg = (struct ext2_group *)toybuf;
|
|
int treeblocks = TT.treeblocks, treeinodes = TT.treeinodes;
|
|
|
|
sb.block_group_nr = SWAP_LE16(i);
|
|
|
|
// Write superblock and pad it up to block size
|
|
xwrite(TT.fsfd, &sb, sizeof(struct ext2_superblock));
|
|
temp = TT.blocksize - sizeof(struct ext2_superblock);
|
|
if (!i && TT.blocksize > 1024) temp -= 1024;
|
|
memset(toybuf, 0, TT.blocksize);
|
|
xwrite(TT.fsfd, toybuf, temp);
|
|
|
|
// Loop through groups to write group descriptor table.
|
|
for(j=0; j<TT.groups; j++) {
|
|
|
|
// Figure out what sector this group starts in.
|
|
used = group_superblock_overhead(j);
|
|
|
|
// Find next array slot in this block (flush block if full).
|
|
slot = j % (TT.blocksize/sizeof(struct ext2_group));
|
|
if (!slot) {
|
|
if (j) xwrite(TT.fsfd, bg, TT.blocksize);
|
|
memset(bg, 0, TT.blocksize);
|
|
}
|
|
|
|
// How many free inodes in this group?
|
|
temp = TT.inodespg;
|
|
if (!i) temp -= INODES_RESERVED;
|
|
if (temp > treeinodes) {
|
|
treeinodes -= temp;
|
|
temp = 0;
|
|
} else {
|
|
temp -= treeinodes;
|
|
treeinodes = 0;
|
|
}
|
|
bg[slot].free_inodes_count = SWAP_LE16(temp);
|
|
|
|
// How many free blocks in this group?
|
|
temp = TT.inodespg/(TT.blocksize/sizeof(struct ext2_inode)) + 2;
|
|
temp = end-used-temp;
|
|
if (temp > treeblocks) {
|
|
treeblocks -= temp;
|
|
temp = 0;
|
|
} else {
|
|
temp -= treeblocks;
|
|
treeblocks = 0;
|
|
}
|
|
bg[slot].free_blocks_count = SWAP_LE32(temp);
|
|
|
|
// Fill out rest of group structure
|
|
used += j*TT.blockbits;
|
|
bg[slot].block_bitmap = SWAP_LE32(used++);
|
|
bg[slot].inode_bitmap = SWAP_LE32(used++);
|
|
bg[slot].inode_table = SWAP_LE32(used);
|
|
bg[slot].used_dirs_count = 0; // (TODO)
|
|
}
|
|
xwrite(TT.fsfd, bg, TT.blocksize);
|
|
}
|
|
|
|
// Now write out stuff that every block group has.
|
|
|
|
// Write block usage bitmap
|
|
|
|
start += 2 + itable;
|
|
memset(toybuf, 0, TT.blocksize);
|
|
bits_set(toybuf, 0, start);
|
|
bits_set(toybuf, end, TT.blockbits-end);
|
|
temp = TT.treeblocks - usedblocks;
|
|
if (temp) {
|
|
if (end-start > temp) temp = end-start;
|
|
bits_set(toybuf, start, temp);
|
|
}
|
|
xwrite(TT.fsfd, toybuf, TT.blocksize);
|
|
|
|
// Write inode bitmap
|
|
memset(toybuf, 0, TT.blocksize);
|
|
j = 0;
|
|
if (!i) bits_set(toybuf, 0, j = INODES_RESERVED);
|
|
bits_set(toybuf, TT.inodespg, slot = TT.blockbits-TT.inodespg);
|
|
temp = TT.treeinodes - usedinodes;
|
|
if (temp) {
|
|
if (slot-j > temp) temp = slot-j;
|
|
bits_set(toybuf, j, temp);
|
|
}
|
|
xwrite(TT.fsfd, toybuf, TT.blocksize);
|
|
|
|
// Write inode table for this group (TODO)
|
|
for (j = 0; j<TT.inodespg; j++) {
|
|
slot = j % (TT.blocksize/sizeof(struct ext2_inode));
|
|
if (!slot) {
|
|
if (j) xwrite(TT.fsfd, in, TT.blocksize);
|
|
memset(in, 0, TT.blocksize);
|
|
}
|
|
if (!i && j<INODES_RESERVED) {
|
|
// Write root inode
|
|
if (j == 2) fill_inode(in+slot, dtb);
|
|
} else if (dti) {
|
|
fill_inode(in+slot, dti);
|
|
dti = treenext(dti);
|
|
}
|
|
}
|
|
xwrite(TT.fsfd, in, TT.blocksize);
|
|
|
|
while (dtb) {
|
|
// TODO write index data block
|
|
// TODO write root directory data block
|
|
// TODO write directory data block
|
|
// TODO write file data block
|
|
put_zeroes(TT.blocksize);
|
|
start++;
|
|
if (start == end) break;
|
|
}
|
|
// Write data blocks (TODO)
|
|
put_zeroes((end-start) * TT.blocksize);
|
|
}
|
|
}
|