include/kernel/dri/fs/ext2/ext2.h - bluejay - Git - code.swisschili.sh

 #pragma once

 #include <vfs.h>

 struct ext2_superblock
 {
 	/// Total number of inodes
 	uint total_inodes;

 	/// Total number of blocks
 	uint total_blocks;

 	/// Number of blocks reserved for superuser
 	uint blocks_reserved_for_superuser;

 	/// Number of unallocated blocks
 	uint unallocated_blocks;

 	/// Number of unallocated inodes
 	uint unallocated_inodes;

 	/// Block number containing the superblock
 	uint superblock_block_number;

 	/// the number to shift 1024 to the left by to get the block size
 	uint block_size_shift;

 	/// the number to shift 1024 to the left by to get the fragment size
 	uint fragment_size_shift;

 	/// Number of blocks in one block group
 	uint blocks_per_block_group;

 	/// Number of fragments in one block group
 	uint fragments_per_block_group;

 	/// Number of inodse in one block group
 	uint inodes_per_block_group;

 	/// UNIX time of last mount
 	uint last_mount_time;

 	/// UNIX time of last write
 	uint last_write_time;

 	/// Number of mounts since last consistency check
 	ushort mounts_since_last_fsck;

 	/// Number of mounts allowed between consistency checks
 	ushort mounts_allowed_before_fsck;

 	/// EXT2 signature, should be 0xef53
 	ushort signature;

 	/// File system state, see enum ext2_fs_state
 	ushort state;

 	/// What to do in case of an error, see enum ext2_error_case
 	ushort error_case;

 	/// Minor portion of version
 	ushort version_minor;

 	/// UNIX time of last consistency check
 	uint last_fsck_time;

 	/// Max time between consistency checks
 	uint fsck_time_interval;

 	/// Operating system ID of creator
 	uint creator_os_id;

 	/// Major portion of version
 	uint version_major;

 	/// User ID that can use reserved blocks
 	ushort reserved_blocks_uid;

 	/// Group ID that can use reserved blocks
 	ushort reserved_blocks_gid;
 };

 enum ext2_fs_state
 {
 	EXT2_STATE_CLEAN = 1,
 	EXT2_STATE_ERRORS = 2,
 };

 enum ext2_error_case
 {
 	EXT2_ERROR_IGNORE = 1,
 	EXT2_ERROR_REMOUNT = 2,
 	EXT2_ERROR_KPANIC = 3,
 };

 enum ext2_os_id
 {
 	EXT2_OS_LINUX = 0,
 	EXT2_OS_HURD,
 	EXT2_OS_MASIX,
 	EXT2_OS_FREEBSD,
 	EXT2_OS_OTHER_BSD,
 };

 #define EXT2_SIGNATURE 0xef53

 struct ext2_block_group_descriptor
 {
 	/// Address of block usage bitmap
 	uint block_bitmap; // 4

 	/// Address of inode usage bitmap
 	uint inode_bitmap; // 8

 	/// Starting block address of inode table
 	uint inode_table_start_block; // 12

 	/// Number of unallocated blocks in this group
 	ushort unallocated_blocks; // 14

 	/// Number of unallocated inodes in this group
 	ushort unallocated_inodes; // 16

 	/// Number of directories in this group
 	ushort num_dirs; // 18

 	ushort padding; // 20

 	uchar reserved[12]; // 32
 };

 struct ext2_inode
 {
 	/// The format and permissions of the file, see EXT2_S_*
 	ushort mode;

 	/// The user id of the owner
 	ushort uid;

 	/// The lower 32 bits of the file size
 	uint size;

 	/// Last time this was accessed in UNIX time
 	uint access_time;

 	/// Time this was created in UNIX time
 	uint created_time;

 	/// Time this was last modified in UNIX time
 	uint modified_time;

 	/// Time this was deleted in UNIX time
 	uint deleted_time;

 	/// Owner group id
 	ushort gid;

 	/// Reference count for hard links
 	ushort links_count;

 	/// Number of 512 byte blocks storing this files data, NOT EXT2 blocks!
 	uint num_blocks;

 	/// Flags describing how this file can be accessed
 	uint flags;

 	/// First field reserved for the operating system
 	uint os_reserved_1;

 	union
 	{
 		/// The blocks of this file
 		uint blocks[15];

 		struct
 		{
 			/// The direct blocks
 			uint direct_blocks[12];

 			/// The single indirect block
 			uint ind_block;

 			/// The double indirect block
 			uint ind2_block;

 			/// The triple indirect block
 			uint ind3_block;
 		};
 	};

 	/// Used by NFS to version files
 	uint generation;

 	/// File attributes, unused
 	uint file_acl;

 	/// Directory attributes, unused
 	uint dir_acl;

 	/// Location of file fragment, unused
 	uint faddr;

 	/// Second field reserved for the operating system
 	uchar os_reserved_2[12];
 };

 enum
 {
 	// File types
 	EXT2_S_IFSOCK = 0xc000,
 	EXT2_S_IFLINK = 0xa000,
 	EXT2_S_IFREG = 0x8000,
 	EXT2_S_IFBLK = 0x6000,
 	EXT2_S_IFDIR = 0x4000,
 	EXT2_S_IFCHR = 0x2000,
 	EXT2_S_IFIFO = 0x1000,

 	/// Set UID
 	EXT2_S_ISUID = 0x0800,
 	/// Set GUID
 	EXT2_S_ISGID = 0x0400,
 	/// Sticky
 	EXT2_S_ISVTX = 0x0200,

 	// Normal UNIX file permissions
 	EXT2_S_IRUSR = 0x0100,
 	EXT2_S_IWUSR = 0x0080,
 	EXT2_S_IXUSR = 0x0040,
 	EXT2_S_IRGRP = 0x0020,
 	EXT2_S_IWGRP = 0x0010,
 	EXT2_S_IXGRP = 0x0008,
 	EXT2_S_IROTH = 0x0004,
 	EXT2_S_IWOTH = 0x0002,
 	EXT2_S_IXOTH = 0x0001,
 };

 /// File type flag (used on inode->mode)
 #define EXT2_F_TYPE 0xf000

 struct ext2_dirent
 {
 	uint inode;
 	ushort rec_len;
 	uchar name_len;
 	uchar file_type;
 	char name[];
 };

 /// Read a file system block (0-indexed), if necessary multiple disk blocks
 /// will be read automatically
 void ext2_read_block(struct ext2_superblock *sb, void *buffer, uint block);
 void ext2_write_block(struct ext2_superblock *sb, void *buffer, uint block);

 struct ext2_superblock ext2_read_superblock();

 void ext2_write_superblock(struct ext2_superblock *sb);

 // Just for fun, corrupt the superblock (obviously don't actually do this)
 void ext2_corrupt_superblock_for_fun();

 void ext2_mount(struct fs_node *where);

 bool ext2_valid_filesystem();

 bool ext2_find_inode(struct ext2_superblock *sb, uint number, struct ext2_inode *inode);

 /// Load a block group descriptor for a certain block group
 struct ext2_block_group_descriptor ext2_load_block_group_descriptor(
 	struct ext2_superblock *sb, uint block_group);

 /// List the contents of a directory dir. Calls `cb` for each item. If `dir` is
 /// not a directory, returns false. Otherwise returns true.
 bool ext2_dir_ls(struct ext2_superblock *sb,
 				 struct ext2_inode *dir,
 				 void (*cb)(uint inode,
 							const char *name,
 							void *data),
 				 void *data);

 /// Read a data block for the inode, 0 being the first block of the file.
 bool ext2_read_inode_block(struct ext2_superblock *sb,
 						   struct ext2_inode *inode,
 						   void *buffer,
 						   uint block);

 ssize_t ext2_read_inode(struct ext2_superblock *sb, struct ext2_inode *inode, void *buffer, ssize_t size);

 /**
  * @brief Set a block in a bitmap
  * @param bitmap_block The first block of the bitmap, not necessarily the block
  * that this specific bit is in.
  * @param index The bit to check, starting at 0
  * @returns The value of the bit
  */
 bool ext2_check_in_bitmap(struct ext2_superblock *sb, uint bitmap_block,
 						  uint index);

 /**
  * @brief Set a block in a bitmap
  * @param bitmap_block The first block of the bitmap, not necessarily the block
  * that this specific bit is in.
  * @param index The bit to set, starting at 0
  * @param value The value of the bit, 0 for 0, non-0 for 1
  */
 void ext2_set_in_bitmap(struct ext2_superblock *sb, uint bitmap_block,
 						uint index, bool value);

 /**
  * @brief Find the first zero bit in a bitset
  * @param bitmap_block The first block of the bitmap
  * @param num_blocks The number of blocks in the bitmap, or ~0 for no limit
  * (UNSAFE).
  * @param start_at The first bit to search from, useful if you want to ignore
  * the first reserved inodes.
  * @returns The index of the first zero bit, or -1 if there is none
  */
 uint ext2_first_zero_bit(struct ext2_superblock *sb, uint bitmap_block,
 						 uint num_blocks, uint start_at);

 uint ext2_first_free_inode(struct ext2_superblock *sb);
	#pragma once

	#include <vfs.h>

	struct ext2_superblock
	{
	/// Total number of inodes
	uint total_inodes;

	/// Total number of blocks
	uint total_blocks;

	/// Number of blocks reserved for superuser
	uint blocks_reserved_for_superuser;

	/// Number of unallocated blocks
	uint unallocated_blocks;

	/// Number of unallocated inodes
	uint unallocated_inodes;

	/// Block number containing the superblock
	uint superblock_block_number;

	/// the number to shift 1024 to the left by to get the block size
	uint block_size_shift;

	/// the number to shift 1024 to the left by to get the fragment size
	uint fragment_size_shift;

	/// Number of blocks in one block group
	uint blocks_per_block_group;

	/// Number of fragments in one block group
	uint fragments_per_block_group;

	/// Number of inodse in one block group
	uint inodes_per_block_group;

	/// UNIX time of last mount
	uint last_mount_time;

	/// UNIX time of last write
	uint last_write_time;

	/// Number of mounts since last consistency check
	ushort mounts_since_last_fsck;

	/// Number of mounts allowed between consistency checks
	ushort mounts_allowed_before_fsck;

	/// EXT2 signature, should be 0xef53
	ushort signature;

	/// File system state, see enum ext2_fs_state
	ushort state;

	/// What to do in case of an error, see enum ext2_error_case
	ushort error_case;

	/// Minor portion of version
	ushort version_minor;

	/// UNIX time of last consistency check
	uint last_fsck_time;

	/// Max time between consistency checks
	uint fsck_time_interval;

	/// Operating system ID of creator
	uint creator_os_id;

	/// Major portion of version
	uint version_major;

	/// User ID that can use reserved blocks
	ushort reserved_blocks_uid;

	/// Group ID that can use reserved blocks
	ushort reserved_blocks_gid;
	};

	enum ext2_fs_state
	{
	EXT2_STATE_CLEAN = 1,
	EXT2_STATE_ERRORS = 2,
	};

	enum ext2_error_case
	{
	EXT2_ERROR_IGNORE = 1,
	EXT2_ERROR_REMOUNT = 2,
	EXT2_ERROR_KPANIC = 3,
	};

	enum ext2_os_id
	{
	EXT2_OS_LINUX = 0,
	EXT2_OS_HURD,
	EXT2_OS_MASIX,
	EXT2_OS_FREEBSD,
	EXT2_OS_OTHER_BSD,
	};

	#define EXT2_SIGNATURE 0xef53

	struct ext2_block_group_descriptor
	{
	/// Address of block usage bitmap
	uint block_bitmap; // 4

	/// Address of inode usage bitmap
	uint inode_bitmap; // 8

	/// Starting block address of inode table
	uint inode_table_start_block; // 12

	/// Number of unallocated blocks in this group
	ushort unallocated_blocks; // 14

	/// Number of unallocated inodes in this group
	ushort unallocated_inodes; // 16

	/// Number of directories in this group
	ushort num_dirs; // 18

	ushort padding; // 20

	uchar reserved[12]; // 32
	};

	struct ext2_inode
	{
	/// The format and permissions of the file, see EXT2_S_*
	ushort mode;

	/// The user id of the owner
	ushort uid;

	/// The lower 32 bits of the file size
	uint size;

	/// Last time this was accessed in UNIX time
	uint access_time;

	/// Time this was created in UNIX time
	uint created_time;

	/// Time this was last modified in UNIX time
	uint modified_time;

	/// Time this was deleted in UNIX time
	uint deleted_time;

	/// Owner group id
	ushort gid;

	/// Reference count for hard links
	ushort links_count;

	/// Number of 512 byte blocks storing this files data, NOT EXT2 blocks!
	uint num_blocks;

	/// Flags describing how this file can be accessed
	uint flags;

	/// First field reserved for the operating system
	uint os_reserved_1;

	union
	{
	/// The blocks of this file
	uint blocks[15];

	struct
	{
	/// The direct blocks
	uint direct_blocks[12];

	/// The single indirect block
	uint ind_block;

	/// The double indirect block
	uint ind2_block;

	/// The triple indirect block
	uint ind3_block;
	};
	};

	/// Used by NFS to version files
	uint generation;

	/// File attributes, unused
	uint file_acl;

	/// Directory attributes, unused
	uint dir_acl;

	/// Location of file fragment, unused
	uint faddr;

	/// Second field reserved for the operating system
	uchar os_reserved_2[12];
	};

	enum
	{
	// File types
	EXT2_S_IFSOCK = 0xc000,
	EXT2_S_IFLINK = 0xa000,
	EXT2_S_IFREG = 0x8000,
	EXT2_S_IFBLK = 0x6000,
	EXT2_S_IFDIR = 0x4000,
	EXT2_S_IFCHR = 0x2000,
	EXT2_S_IFIFO = 0x1000,

	/// Set UID
	EXT2_S_ISUID = 0x0800,
	/// Set GUID
	EXT2_S_ISGID = 0x0400,
	/// Sticky
	EXT2_S_ISVTX = 0x0200,

	// Normal UNIX file permissions
	EXT2_S_IRUSR = 0x0100,
	EXT2_S_IWUSR = 0x0080,
	EXT2_S_IXUSR = 0x0040,
	EXT2_S_IRGRP = 0x0020,
	EXT2_S_IWGRP = 0x0010,
	EXT2_S_IXGRP = 0x0008,
	EXT2_S_IROTH = 0x0004,
	EXT2_S_IWOTH = 0x0002,
	EXT2_S_IXOTH = 0x0001,
	};

	/// File type flag (used on inode->mode)
	#define EXT2_F_TYPE 0xf000

	struct ext2_dirent
	{
	uint inode;
	ushort rec_len;
	uchar name_len;
	uchar file_type;
	char name[];
	};

	/// Read a file system block (0-indexed), if necessary multiple disk blocks
	/// will be read automatically
	void ext2_read_block(struct ext2_superblock sb, void buffer, uint block);
	void ext2_write_block(struct ext2_superblock sb, void buffer, uint block);

	struct ext2_superblock ext2_read_superblock();

	void ext2_write_superblock(struct ext2_superblock *sb);

	// Just for fun, corrupt the superblock (obviously don't actually do this)
	void ext2_corrupt_superblock_for_fun();

	void ext2_mount(struct fs_node *where);

	bool ext2_valid_filesystem();

	bool ext2_find_inode(struct ext2_superblock sb, uint number, struct ext2_inode inode);

	/// Load a block group descriptor for a certain block group
	struct ext2_block_group_descriptor ext2_load_block_group_descriptor(
	struct ext2_superblock *sb, uint block_group);

	/// List the contents of a directory dir. Calls `cb` for each item. If `dir` is
	/// not a directory, returns false. Otherwise returns true.
	bool ext2_dir_ls(struct ext2_superblock *sb,
	struct ext2_inode *dir,
	void (*cb)(uint inode,
	const char *name,
	void *data),
	void *data);

	/// Read a data block for the inode, 0 being the first block of the file.
	bool ext2_read_inode_block(struct ext2_superblock *sb,
	struct ext2_inode *inode,
	void *buffer,
	uint block);

	ssize_t ext2_read_inode(struct ext2_superblock sb, struct ext2_inode inode, void *buffer, ssize_t size);

	/**
	* @brief Set a block in a bitmap
	* @param bitmap_block The first block of the bitmap, not necessarily the block
	* that this specific bit is in.
	* @param index The bit to check, starting at 0
	* @returns The value of the bit
	*/
	bool ext2_check_in_bitmap(struct ext2_superblock *sb, uint bitmap_block,
	uint index);

	/**
	* @brief Set a block in a bitmap
	* @param bitmap_block The first block of the bitmap, not necessarily the block
	* that this specific bit is in.
	* @param index The bit to set, starting at 0
	* @param value The value of the bit, 0 for 0, non-0 for 1
	*/
	void ext2_set_in_bitmap(struct ext2_superblock *sb, uint bitmap_block,
	uint index, bool value);

	/**
	* @brief Find the first zero bit in a bitset
	* @param bitmap_block The first block of the bitmap
	* @param num_blocks The number of blocks in the bitmap, or ~0 for no limit
	* (UNSAFE).
	* @param start_at The first bit to search from, useful if you want to ignore
	* the first reserved inodes.
	* @returns The index of the first zero bit, or -1 if there is none
	*/
	uint ext2_first_zero_bit(struct ext2_superblock *sb, uint bitmap_block,
	uint num_blocks, uint start_at);

	uint ext2_first_free_inode(struct ext2_superblock *sb);