diff options
Diffstat (limited to 'src/kernel/fs/ext2.h')
| -rw-r--r-- | src/kernel/fs/ext2.h | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/src/kernel/fs/ext2.h b/src/kernel/fs/ext2.h new file mode 100644 index 0000000..62105c7 --- /dev/null +++ b/src/kernel/fs/ext2.h @@ -0,0 +1,211 @@ +#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 |