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