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#ifndef MELVIX_EXT2_H
#define MELVIX_EXT2_H
#include <stdint.h>
#include <kernel/fs/vfs.h>
#define EXT2_DIRECT_BLOCKS 12
#define SUPERBLOCK_SIZE 1024
#define ROOT_INODE_NUMBER 2
#define EXT2_S_IFSOCK 0xC000
#define EXT2_S_IFLNK 0xA000
#define EXT2_S_IFREG 0x8000
#define EXT2_S_IFBLK 0x6000
#define EXT2_S_IFDIR 0x4000
#define EXT2_S_IFCHR 0x2000
#define EXT2_S_IFIFO 0x1000
// http://wiki.osdev.org/Ext2#Locating_the_Superblock
typedef struct superblock {
uint32_t total_inodes;
uint32_t total_blocks;
uint32_t su_blocks;
uint32_t free_blocks;
uint32_t free_inodes;
uint32_t superblock_idx;
uint32_t log2block_size;
uint32_t log2frag_size;
uint32_t blocks_per_group;
uint32_t frags_per_group;
uint32_t inodes_per_group;
uint32_t mtime;
uint32_t wtime;
uint16_t mount_count;
uint16_t mount_allowed_count;
uint16_t ext2_magic;
uint16_t fs_state;
uint16_t err;
uint16_t minor;
uint32_t last_check;
uint32_t interval;
uint32_t os_id;
uint32_t major;
uint16_t r_userid;
uint16_t r_groupid;
// Extensions
uint32_t first_inode;
uint16_t inode_size;
uint16_t superblock_group;
uint32_t optional_feature;
uint32_t required_feature;
uint32_t readonly_feature;
char fs_id[16];
char vol_name[16];
char last_mount_path[64];
uint32_t compression_method;
uint8_t file_pre_alloc_blocks;
uint8_t dir_pre_alloc_blocks;
uint16_t unused1;
char journal_id[16];
uint32_t journal_inode;
uint32_t journal_device;
uint32_t orphan_head;
char unused2[1024 - 236];
} __attribute__((packed)) superblock_t;
typedef struct bgd {
uint32_t block_bitmap;
uint32_t inode_bitmap;
uint32_t inode_table;
uint32_t free_blocks;
uint32_t free_inodes;
uint32_t num_dirs;
uint32_t unused1;
uint32_t unused2;
} __attribute__((packed)) bgd_t;
typedef struct direntry {
uint32_t inode;
uint16_t size;
uint8_t name_len;
uint8_t type;
char name[];
} __attribute__((packed)) direntry_t;
typedef struct inode {
uint16_t permission;
uint16_t userid;
uint32_t size;
uint32_t atime;
uint32_t ctime;
uint32_t mtime;
uint32_t dtime;
uint16_t gid;
uint16_t hard_links;
uint32_t num_sectors;
uint32_t flags;
uint32_t os_specific1;
uint32_t blocks[EXT2_DIRECT_BLOCKS + 3];
uint32_t generation;
uint32_t file_acl;
union {
uint32_t dir_acl;
uint32_t size_high;
};
uint32_t f_block_addr;
char os_specific2[12];
} __attribute__((packed)) inode_t;
typedef struct ext2_cache {
uint32_t block;
uint32_t times;
uint8_t dirty;
char *block_data;
} ext2_cache_t;
typedef struct ext2_fs {
vfs_node_t *disk_device;
superblock_t *sb;
bgd_t *bgds;
uint32_t block_size;
uint32_t blocks_per_group;
uint32_t inodes_per_group;
uint32_t total_groups;
uint32_t bgd_blocks;
} ext2_fs_t;
uint32_t ext2_file_size(vfs_node_t *node);
void ext2_mkdir(vfs_node_t *parent, char *name, uint16_t permission);
void ext2_mkfile(vfs_node_t *parent, char *name, uint16_t permission);
void ext2_create_entry(vfs_node_t *parent, char *entry_name, uint32_t entry_inode);
void ext2_unlink(vfs_node_t *parent, char *name);
char **ext2_listdir(vfs_node_t *parent);
vfs_node_t *ext2_finddir(vfs_node_t *parent, char *name);
void ext2_create_entry(vfs_node_t *parent, char *entry_name, uint32_t entry_inode);
void ext2_remove_entry(vfs_node_t *parent, char *entry_name);
void ext2_chmod(vfs_node_t *file, uint32_t mode);
uint32_t ext2_read(vfs_node_t *file, uint32_t offset, uint32_t size, char *buf);
uint32_t ext2_write(vfs_node_t *file, uint32_t offset, uint32_t size, char *buf);
void ext2_open(vfs_node_t *file, uint32_t flags);
void ext2_close();
void read_inode_metadata(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx);
void write_inode_metadata(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx);
uint32_t read_inode_filedata(ext2_fs_t *ext2fs, inode_t *inode, uint32_t offset, uint32_t size,
char *buf);
void write_inode_filedata(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx, uint32_t offset,
uint32_t size, char *buf);
char *read_inode_block(ext2_fs_t *ext2fs, inode_t *inode, uint32_t iblock);
void write_inode_block(ext2_fs_t *ext2fs, inode_t *inode, uint32_t iblock, char *buf);
void read_disk_block(ext2_fs_t *ext2fs, uint32_t block, char *buf);
void write_disk_block(ext2_fs_t *ext2fs, uint32_t block, char *buf);
void rewrite_bgds(ext2_fs_t *ext2fs);
void rewrite_superblock(ext2_fs_t *ext2fs);
int alloc_inode_metadata_block(uint32_t *block_ptr, ext2_fs_t *ext2fs, inode_t *inode,
uint32_t inode_idx, char *buffer, unsigned int block_overwrite);
uint32_t get_disk_block_number(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_block);
void set_disk_block_number(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx,
uint32_t inode_block, uint32_t disk_block);
uint32_t ext2_alloc_block(ext2_fs_t *ext2fs);
void ext2_free_block(ext2_fs_t *ext2fs, uint32_t block);
void alloc_inode_block(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx, uint32_t block);
void free_inode_block(ext2_fs_t *ext2fs, inode_t *inode, uint32_t inode_idx, uint32_t block);
uint32_t alloc_inode(ext2_fs_t *ext2fs);
void free_inode(ext2_fs_t *ext2fs, uint32_t inode);
vfs_node_t *get_ext2_root(ext2_fs_t *ext2fs, inode_t *inode);
void ext2_init(char *device_path, char *mountpoint);
#endif
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