Import backup from 2005-06-21

kernel/fs/ext2/ext2.cpp

@@ -0,0 +1,37 @@
+// ext2.cpp
+// ext2 filesystem driver for HOS
+// Author: Josh Holtrop
+// Date: 05/10/05
+// Modified: 05/10/05
+
+#define _HOS_CPP_ _HOS_CPP_
+
+extern "C" {
+#include "display/kout.h"
+}
+
+#include "ext2.h"
+
+Ext2fs::Ext2fs(device_t dev)
+{
+	myDevice = dev;
+	if (block_read(DEV_MAJOR(dev), DEV_MINOR(dev), 2, 2, &mySuper) < 1024)
+	{
+		myError = -1;
+		return;
+	}
+	if (mySuper.s_magic != EXT2_MAGIC)
+	{
+		myError = -2;
+		return;
+	}
+	myError = 0;
+	mySuperDirty = 0;
+	kprintf("Device: %d\n", myDevice);
+}
+
+Ext2fs::~Ext2fs()
+{
+	if (mySuperDirty)
+		block_write(DEV_MAJOR(myDevice), DEV_MINOR(myDevice), 2, 2, &mySuper);
+}

kernel/fs/ext2/ext2.h

@@ -0,0 +1,156 @@
+// ext2.h
+// ext2 filesystem driver for HOS
+// Author: Josh Holtrop
+// Date: 05/10/05
+// Modified: 05/23/05
+
+#ifndef __HOS_EXT2_H__
+#define __HOS_EXT2_H__ __HOS_EXT2_H__
+
+#define EXT2_MAGIC		0xEF53
+#define EXT2_NAME_LEN		255
+
+#define EXT2_I_MODE_ATTR_MASK	0x0FFF
+#define EXT2_I_MODE_OX		0x0001
+#define EXT2_I_MODE_OW		0x0002
+#define EXT2_I_MODE_OR		0x0004
+#define EXT2_I_MODE_GX		0x0008
+#define EXT2_I_MODE_GW		0x0010
+#define EXT2_I_MODE_GR		0x0020
+#define EXT2_I_MODE_UX		0x0040
+#define EXT2_I_MODE_UW		0x0080
+#define EXT2_I_MODE_UR		0x0100
+#define EXT2_I_MODE_STICKY	0x0200
+#define EXT2_I_MODE_SGID	0x0400
+#define EXT2_I_MODE_SUID	0x0800
+
+#define EXT2_I_MODE_TYPE_MASK	0xF000
+#define EXT2_I_MODE_FIFO	0x1000
+#define EXT2_I_MODE_CHAR	0x2000
+#define EXT2_I_MODE_DIR		0x4000
+#define EXT2_I_MODE_BLOCK	0x6000
+#define EXT2_I_MODE_FILE	0x8000
+#define EXT2_I_MODE_SYM		0xA000
+#define EXT2_I_MODE_SOCK	0xC000
+
+#define EXT2_I_FLAGS_SEC_DEL	0x01
+#define EXT2_I_FLAGS_UNDELETE	0x02
+#define EXT2_I_FLAGS_COMPRESS	0x04
+#define EXT2_I_FLAGS_SYNC	0x08
+#define EXT2_I_FLAGS_IMMUTABLE	0x10
+#define EXT2_I_FLAGS_APPEND	0x20
+#define EXT2_I_FLAGS_NODUMP	0x40
+
+#define EXT2_INODE_BAD_BLOCKS	1
+#define EXT2_INODE_ROOT		2
+#define EXT2_INODE_ACL_INDEX	3
+#define EXT2_INODE_ACL_DATA	4
+#define EXT2_INODE_BOOT_LOADER	5
+#define EXT2_INODE_UNDELETE_DIR	6
+#define EXT2_INODE_AVAIL	11
+
+#define EXT2_FT_UNKNOWN		0
+#define EXT2_FT_FILE		1
+#define EXT2_FT_DIR		2
+#define EXT2_FT_CHAR		3
+#define EXT2_FT_BLOCK		4
+#define EXT2_FT_FIFO		5
+#define EXT2_FT_SOCK		6
+#define EXT2_FT_SYMLINK		7
+#define EXT2_FT_MAX		8
+
+#include "fs/vfs.h"
+
+typedef struct
+{
+	u32_t	s_inodes_count;		/* Inodes count */
+	u32_t	s_blocks_count;		/* Blocks count */
+	u32_t	s_r_blocks_count;	/* Reserved blocks count */
+	u32_t	s_free_blocks_count;	/* Free blocks count */
+	u32_t	s_free_inodes_count;	/* Free inodes count */
+	u32_t	s_first_data_block;	/* First Data Block */
+	u32_t	s_log_block_size;	/* Block size: 0->1024, 1->2048, 2->4096 */
+	int	s_log_frag_size;	/* Fragment size */
+	u32_t	s_blocks_per_group;	/* # Blocks per group */
+	u32_t	s_frags_per_group;	/* # Fragments per group */
+	u32_t	s_inodes_per_group;	/* # Inodes per group */
+	u32_t	s_mtime;		/* Mount time */
+	u32_t	s_wtime;		/* Write time */
+	u16_t	s_mnt_count;		/* Mount count */
+	short	s_max_mnt_count;	/* Maximal mount count */
+	u16_t	s_magic;		/* Magic signature */
+	u16_t	s_state;		/* File system state */
+	u16_t	s_errors;		/* Behaviour when detecting errors */
+	u16_t	s_minor_rev_level;	/* minor revision level */
+	u32_t	s_lastcheck;		/* time of last check */
+	u32_t	s_checkinterval;	/* max. time between checks */
+	u32_t	s_creator_os;		/* OS */
+	u32_t	s_rev_level;		/* Revision level */
+	u16_t	s_def_resuid;		/* Default uid for reserved blocks */
+	u16_t	s_def_resgid;		/* Default gid for reserved blocks */
+
+	u32_t	s_reserved[235];
+} ext2_super_block_t;
+
+typedef struct
+{
+	u32_t	bg_block_bitmap;	// Blocks bitmap block
+	u32_t	bg_inode_bitmap;	// Inode bitmap block
+	u32_t	bg_inode_table;		// Inode table block
+	u16_t	bg_free_blocks_count;	// Free blocks count
+	u16_t	bg_free_inodes_count;	// Free Inodes count
+	u16_t	bg_used_dirs_count;	// Directories count
+	u16_t	bg_pad1;
+	u32_t	bg_reserved[3];
+} ext2_group_desc_t;
+
+typedef struct
+{
+	u16_t	i_mode;			// File mode
+	u16_t	i_uid;			// Owner UID
+	u32_t	i_size;			// Size in bytes
+	u32_t	i_atime;		// Access time
+	u32_t	i_ctime;		// Creation time
+	u32_t	i_mtime;		// Modification time
+	u32_t	i_dtime;		// Deletion time
+	u16_t	i_gid;			// Group ID
+	u16_t	i_links_count;		// Links count
+	u32_t	i_blocks;		// Blocks count
+	u32_t	i_flags;		// File flags
+	u32_t	i_reserved1;
+	u32_t	i_block[15];		// Pointers to blocks (12 direct, single, double, triple indirect)
+	u32_t	i_version;		// File version (for NFS)
+	u32_t	i_file_acl;		// File ACL
+	u32_t	i_dir_acl;		// Directory ACL
+	u32_t	i_faddr;		// Fragment address
+	u8_t	i_frag;			// Fragment number
+	u8_t	i_fsize;		// Fragment size
+	u16_t	i_pad1;
+	u32_t	i_reserved2[2];
+} ext2_inode_t;
+
+typedef struct
+{
+	u32_t	inode;			// inode number
+	u16_t	length;			// directory entry length
+	u8_t	name_length;		// name length
+	u8_t	file_type;		// File type
+	char	name[EXT2_NAME_LEN];
+} ext2_dir_entry_t;
+
+#ifdef _HOS_CPP_
+
+class Ext2fs : public FileSystem
+{
+protected:
+	ext2_super_block_t mySuper;
+	int	mySuperDirty;
+public:
+	Ext2fs(device_t dev);
+	~Ext2fs();
+};
+
+#endif
+
+#endif
+

kernel/fs/ext2/ext2_old.c

@@ -0,0 +1,762 @@
+// ext2.c
+// Author: Josh Holtrop
+// Date: 08/22/04
+// Modified: 12/24/04
+
+#include "hos_defines.h"
+#include "fs/devices.h"
+#include "display/kout.h"
+#include "ext2.h"
+#include "mm/vmm.h"
+#include "fs/vfs.h"
+#include "lang/lang.h"
+#include "functions.h"
+
+/* Turning an inode number into a (group, inode_index) pair:
+ * group = (inode - 1) / s_inodes_per_group
+ * index = (inode - 1) % s_inodes_per_group
+ */
+
+vfs_fs_t ext2_driver = {ext2_mount_super,	ext2_umount_super,	ext2_stat,
+			ext2__get_root_dir_inode, ext2__link_deref,
+			ext2__free_inodes,	ext2__total_inodes,
+			ext2__free_blocks,	ext2__total_blocks,
+			ext2_alloc_inode,	ext2_free_inode,	ext2_alloc_block,	ext2_free_block,
+			ext2__open_dir,		ext2__read_dir,		ext2__close_dir,
+			ext2__open_file,	ext2__read_file,	ext2__close_file,
+			ext2__open_block_file,	ext2__read_block_file,	ext2__block_file_seek,	ext2__close_block_file};
+
+// initialize the filesystem driver
+int	ext2_init(int fsID)
+{
+	vfs_fs_t *fs;
+	if (( fs = New(vfs_fs_t) ))			// give the VFS our FS structure
+	{
+		*fs = ext2_driver;
+		vfs_register_fs(fsID, fs);
+		return 0;
+	}
+	return -1;
+}
+
+
+// lookup a file name in a directory and store the directory entry for it
+int	ext2_dir_lookup(vfs_mount_t *mount, u32_t dir_inode, char *fileName, ext2_dir_entry_t *direntry)
+{
+	ext2_open_dir_t *dir = ext2_open_dir(mount, dir_inode);
+	if (!dir)
+		return -1;			// bad directory inode number
+	ext2_dir_entry_t dentry;
+	while (!ext2_dir_read_entry(mount, dir, &dentry))
+	{
+		char *dentryName = kcalloc(1, dentry.name_length + 1);
+		memcpy(dentryName, dentry.name, dentry.name_length);
+		int res = strcmp(fileName, dentryName);
+		kfree(dentryName);
+		if (!res)
+		{
+			*direntry = dentry;
+			ext2_close_dir(mount, dir);
+			return 0;
+		}
+	}
+	ext2_close_dir(mount, dir);
+	return -2;
+}
+
+// open a directory by inode number for reading
+ext2_open_dir_t *ext2_open_dir(vfs_mount_t *mount, u32_t inode_number)
+{
+	ext2_open_dir_t *open_dir = New(ext2_open_dir_t);
+	ext2_open_inode_t *open_inode = ext2_open_inode(mount, inode_number);
+	if (!open_inode)
+	{
+		kfree(open_dir);
+		return NULL;
+	}
+	if ((open_inode->inode.i_mode & EXT2_I_MODE_TYPE_MASK) != EXT2_I_MODE_DIR)
+	{
+		ext2_close_inode(mount, open_inode);
+		kfree(open_dir);
+		return NULL;
+	}
+	open_dir->open_inode = open_inode;
+	open_dir->position = 0;
+	return open_dir;
+}
+
+int	ext2_dir_read_entry(vfs_mount_t *mount, ext2_open_dir_t *open_dir, ext2_dir_entry_t *dentry)
+{
+	ext2_super_block_t *super = mount->super;
+	if (open_dir->position >= open_dir->open_inode->inode.i_size)
+		return -1;		// EOF
+	u32_t dir_block = open_dir->position >> (10 + super->s_log_block_size);
+	char *block = kmalloc(2048 << super->s_log_block_size);
+	ext2_inode_seek(mount, open_dir->open_inode, dir_block);
+	if (ext2_read_inode_block(mount, open_dir->open_inode, block))
+		ext2_read_inode_block(mount, open_dir->open_inode, block + (1024 << super->s_log_block_size));
+	ext2_dir_entry_t *dir_entry = (ext2_dir_entry_t *)(block + open_dir->position % (1024 << super->s_log_block_size));
+	if (!dir_entry->inode)
+	{
+		kfree(block);
+		return -2;		// EOF
+	}
+	memcpy(dentry, dir_entry, min(dir_entry->length, sizeof(ext2_dir_entry_t)));
+	open_dir->position += dir_entry->length;
+	kfree(block);
+	return 0;
+}
+
+int	ext2_close_dir(vfs_mount_t *mount, ext2_open_dir_t *open_dir)
+{
+	ext2_close_inode(mount, open_dir->open_inode);
+	kfree(open_dir);
+	return 0;
+}
+
+
+// open an inode for reading
+ext2_open_inode_t *ext2_open_inode(vfs_mount_t *mount, u32_t inode_number)
+{
+	ext2_open_inode_t *open_inode = New(ext2_open_inode_t);
+	if ( ext2_read_inode(mount, inode_number, &(open_inode->inode)) )
+	{
+		kfree(open_inode);
+		return NULL;
+	}
+	open_inode->block = 0;
+	open_inode->block_pointers = NULL;
+	open_inode->block_pointers_start = 0;
+	mount->refs++;
+	return open_inode;
+}
+
+
+// seek to a certain block of an open inode
+int	ext2_inode_seek(vfs_mount_t *mount, ext2_open_inode_t *open_inode, u32_t block_number)
+{
+	ext2_super_block_t *super = mount->super;
+	if (open_inode->inode.i_size <= (block_number << (10 + super->s_log_block_size)))
+		return -1;	// at or past EOF
+	open_inode->block = block_number;
+	return 0;
+}
+
+// returns number of bytes read
+int	ext2_read_inode_block(vfs_mount_t *mount, ext2_open_inode_t *open_inode, void *block)
+{
+	ext2_super_block_t *super = mount->super;
+	if (open_inode->inode.i_size <= (open_inode->block << (10 + super->s_log_block_size)))
+		return 0;	// at or past EOF
+	u32_t	leftover_bytes = open_inode->inode.i_size - (open_inode->block << (10 + super->s_log_block_size));
+	u32_t	block_number = ext2_block_number(mount, open_inode);
+	block_read(mount->major, mount->minor, ext2_FSToDiskBlock(block_number, super),
+		2 << super->s_log_block_size, block);
+	open_inode->block++;
+	return min(leftover_bytes, 1024 << super->s_log_block_size);
+}
+
+
+// close an open inode
+int	ext2_close_inode(vfs_mount_t *mount, ext2_open_inode_t *open_inode)
+{
+	mount->refs--;
+	if (open_inode->block_pointers)
+		kfree(open_inode->block_pointers);		// free the block pointers cache
+	kfree(open_inode);
+	return 0;
+}
+
+
+// check the status of an inode (1-based inode number)
+// -1: invalid inode number
+// 0: free inode
+// 1: allocated inode
+int	ext2_inode_status(vfs_mount_t *mount, u32_t inode_number)
+{
+	ext2_super_block_t *super = mount->super;
+	if (inode_number < 1 || inode_number > super->s_inodes_count)	// inode number invalid
+		return -1;
+	inode_number--;				// turn inode_number into a 0-based index
+	u32_t group = inode_number / super->s_inodes_per_group;
+	u32_t index = inode_number % super->s_inodes_per_group;
+	u32_t inode_bitmap_block = ext2_get_group_desc(mount, group).bg_inode_bitmap + (index >> (13 + super->s_log_block_size));
+	u32_t bitmap_index = index % (8192 << super->s_log_block_size);
+	u8_t *inode_bitmap = kmalloc(1024 << super->s_log_block_size);
+	block_read(mount->major, mount->minor,
+		ext2_FSToDiskBlock(inode_bitmap_block, super), 2 << super->s_log_block_size, inode_bitmap);
+	int inode_status = (inode_bitmap[bitmap_index >> 3] >> (bitmap_index & 0x7)) & 1;
+	kfree(inode_bitmap);
+	return inode_status;
+}
+
+
+// check the status of a block
+// -1: invalid block number
+// 0: free block
+// 1: allocated block
+int	ext2_block_status(vfs_mount_t *mount, u32_t block_number)
+{
+	ext2_super_block_t *super = mount->super;
+	if (block_number < super->s_first_data_block || block_number > super->s_blocks_count)	// block number invalid
+		return -1;
+	block_number -= super->s_first_data_block;
+	u32_t group = block_number / super->s_blocks_per_group;
+	u32_t index = block_number % super->s_blocks_per_group;
+	u32_t block_bitmap_block = ext2_get_group_desc(mount, group).bg_block_bitmap + (index >> (13 + super->s_log_block_size));
+	u32_t bitmap_index = index % (8192 << super->s_log_block_size);
+	u8_t *block_bitmap = kmalloc(1024 << super->s_log_block_size);
+	block_read(mount->major, mount->minor,
+		ext2_FSToDiskBlock(block_bitmap_block, super), 2 << super->s_log_block_size, block_bitmap);
+	int block_status = (block_bitmap[bitmap_index >> 3] >> (bitmap_index & 0x7)) & 1;
+	kfree(block_bitmap);
+	return block_status;
+}
+
+
+// transform open_inode->block (a relative block number) to an absolute block number for the filesystem
+u32_t	ext2_block_number(vfs_mount_t *mount, ext2_open_inode_t *open_inode)
+{
+	if (open_inode->block < 12)
+		return open_inode->inode.i_block[open_inode->block];
+	ext2_super_block_t *super = mount->super;
+	int pointersPerBlock = 256 << super->s_log_block_size;
+	if (open_inode->block_pointers &&			// there is a block pointers cache block allocated
+		(open_inode->block >= open_inode->block_pointers_start) &&	// and the block number is in it
+		(open_inode->block < (open_inode->block_pointers_start + pointersPerBlock)))
+		return open_inode->block_pointers[open_inode->block - open_inode->block_pointers_start];
+	u32_t	rel_block = open_inode->block - 12;
+	if (!open_inode->block_pointers)
+		open_inode->block_pointers = kmalloc(pointersPerBlock << 2);
+	if (rel_block < pointersPerBlock)			// indirect block in i_block[12]
+	{
+		block_read(mount->major, mount->minor, ext2_FSToDiskBlock(open_inode->inode.i_block[12], super),
+			2 << super->s_log_block_size, open_inode->block_pointers);
+		open_inode->block_pointers_start = 12;
+		return open_inode->block_pointers[rel_block];
+	}
+	rel_block -= pointersPerBlock;
+	if (rel_block < (pointersPerBlock * pointersPerBlock))	// double-indirect block in i_block[13]
+	{
+		block_read(mount->major, mount->minor, ext2_FSToDiskBlock(open_inode->inode.i_block[13], super),
+			2 << super->s_log_block_size, open_inode->block_pointers);
+		u32_t	real_block = open_inode->block_pointers[rel_block / pointersPerBlock];
+		block_read(mount->major, mount->minor, ext2_FSToDiskBlock(real_block, super),
+			2 << super->s_log_block_size, open_inode->block_pointers);
+		open_inode->block_pointers_start = 12 + pointersPerBlock + rel_block - (rel_block % pointersPerBlock);
+		return open_inode->block_pointers[rel_block % pointersPerBlock];
+	}
+	// this code shouldn't run unless we are dealing with a 65+mb file ...
+	rel_block -= pointersPerBlock * pointersPerBlock;
+	block_read(mount->major, mount->minor, ext2_FSToDiskBlock(open_inode->inode.i_block[14], super),
+		2 << super->s_log_block_size, open_inode->block_pointers);
+	u32_t	index_1 = rel_block / (pointersPerBlock * pointersPerBlock);
+	u32_t	leftover_1 = rel_block % (pointersPerBlock * pointersPerBlock);
+	u32_t	block_1 = open_inode->block_pointers[index_1];
+	block_read(mount->major, mount->minor, ext2_FSToDiskBlock(block_1, super),
+		2 << super->s_log_block_size, open_inode->block_pointers);
+	u32_t	index_2 = leftover_1 / pointersPerBlock;
+	u32_t	leftover_2 = leftover_1 % pointersPerBlock;
+	u32_t	block_2 = open_inode->block_pointers[index_2];
+	block_read(mount->major, mount->minor, ext2_FSToDiskBlock(block_2, super),
+		2 << super->s_log_block_size, open_inode->block_pointers);
+	open_inode->block_pointers_start = 12 + (pointersPerBlock + 1) * pointersPerBlock + rel_block - (rel_block % pointersPerBlock);
+	return open_inode->block_pointers[leftover_2];
+}
+
+
+// read the inode structure from the device
+int	ext2_read_inode(vfs_mount_t *mount, u32_t inode, ext2_inode_t *dat)
+{
+	if (ext2_inode_status(mount, inode) != 1)
+		return -1;			// free or invalid inode number
+	ext2_super_block_t *super = mount->super;
+	inode--;				// turn inode into a 0-based index
+	u32_t group = inode / super->s_inodes_per_group;
+	u32_t index = inode % super->s_inodes_per_group;
+	u32_t inodeAddr = (ext2_get_group_desc(mount, group).bg_inode_table <<
+			 (10 + super->s_log_block_size)) + (index << 7);
+	void *block = kmalloc(512);
+	block_read(mount->major, mount->minor, inodeAddr >> 9, 1, block);
+	memcpy(dat, (block + (inodeAddr & 0x1FF)), sizeof(ext2_inode_t));
+	kfree(block);
+	return 0;
+}
+
+// write an inode structure to the device
+int	ext2_write_inode(vfs_mount_t *mount, u32_t inode, ext2_inode_t *dat)
+{
+	if (ext2_inode_status(mount, inode) != 1)
+		return -1;			// free or invalid inode number
+	ext2_super_block_t *super = mount->super;
+	inode--;				// turn inode into a 0-based index
+	u32_t group = inode / super->s_inodes_per_group;
+	u32_t index = inode % super->s_inodes_per_group;
+	u32_t inodeAddr = (ext2_get_group_desc(mount, group).bg_inode_table <<
+			 (10 + super->s_log_block_size)) + (index << 7);
+	void *block = kmalloc(512);
+	block_read(mount->major, mount->minor, inodeAddr >> 9, 1, block);
+	memcpy( (block + (inodeAddr & 0x1FF)), dat, sizeof(ext2_inode_t));
+	block_write(mount->major, mount->minor, inodeAddr >> 9, 1, block);
+	kfree(block);
+	return 0;
+}
+
+// read the group descriptor structure from the device and return it
+ext2_group_desc_t	ext2_get_group_desc(vfs_mount_t *mount, u32_t group)
+{
+	ext2_super_block_t *super = mount->super;
+	u32_t groupDescAddr = ((1 + super->s_first_data_block) << (10 + super->s_log_block_size)) + (group << 5);
+	void *block = kmalloc(512);
+	block_read(mount->major, mount->minor, groupDescAddr >> 9, 1, block);
+	ext2_group_desc_t gd = *(ext2_group_desc_t *)(block + (groupDescAddr & 0x1FF));
+	kfree(block);
+	return gd;
+}
+
+// write the group descriptor structure to the device
+void	ext2_write_group_desc(vfs_mount_t *mount, u32_t group_num, ext2_group_desc_t *gd)
+{
+	ext2_super_block_t *super = mount->super;
+	u32_t groupDescAddr = ((1 + super->s_first_data_block) << (10 + super->s_log_block_size)) + (group_num << 5);
+	void *block = kmalloc(512);
+	block_read(mount->major, mount->minor, groupDescAddr >> 9, 1, block);
+	memcpy( (block + (groupDescAddr & 0x1FF)), gd, sizeof(ext2_group_desc_t) );
+	block_write(mount->major, mount->minor, groupDescAddr >> 9, 1, block);
+	kfree(block);
+}
+
+// allocate an inode and return its number
+u32_t	ext2_alloc_inode(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	if (!super->s_free_inodes_count)
+		return 0;		// no free inodes
+	int bg, bg_max = ext2_num_block_groups(super);
+	for (bg = 0; bg < bg_max; bg++)
+	{
+		ext2_group_desc_t group_desc = ext2_get_group_desc(mount, bg);
+		if (group_desc.bg_free_inodes_count)
+		{
+			u32_t node = ext2_reserve_node(mount, group_desc.bg_inode_bitmap, super->s_inodes_per_group);
+			group_desc.bg_free_inodes_count--;
+			ext2_write_group_desc(mount, bg, &group_desc);
+			super->s_free_inodes_count--;
+			return bg * super->s_inodes_per_group + node + 1;
+		}
+	}
+	return 0;
+}
+
+int	ext2_free_inode(vfs_mount_t *mount, u32_t inode_number)
+{
+	ext2_super_block_t *super = mount->super;
+	if (inode_number < 11 || inode_number > super->s_inodes_count)
+		return -1;	// invalid inode number
+	if (ext2_inode_status(mount, inode_number) != 1)
+		return -2;	// inode not allocated
+	inode_number--;		// now a 0-based inode number
+	int bg = inode_number / super->s_inodes_per_group;
+	ext2_group_desc_t group_desc = ext2_get_group_desc(mount, bg);
+	ext2_free_node(mount, group_desc.bg_inode_bitmap, inode_number % super->s_inodes_per_group);
+	group_desc.bg_free_inodes_count++;
+	ext2_write_group_desc(mount, bg, &group_desc);
+	super->s_free_inodes_count++;
+	return 0;
+}
+
+// allocate a block and return its number
+u32_t	ext2_alloc_block(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	if (!super->s_free_blocks_count)
+		return 0;		// no free blocks
+	int bg, bg_max = ext2_num_block_groups(super);
+	for (bg = 0; bg < bg_max; bg++)
+	{
+		ext2_group_desc_t group_desc = ext2_get_group_desc(mount, bg);
+		if (group_desc.bg_free_blocks_count)
+		{
+			u32_t node = ext2_reserve_node(mount, group_desc.bg_block_bitmap, super->s_blocks_per_group);
+			group_desc.bg_free_blocks_count--;
+			ext2_write_group_desc(mount, bg, &group_desc);
+			super->s_free_blocks_count--;
+			return bg * super->s_blocks_per_group + node + super->s_first_data_block;
+		}
+	}
+	return 0;
+}
+
+int	ext2_free_block(vfs_mount_t *mount, u32_t block_number)
+{
+	ext2_super_block_t *super = mount->super;
+	if (block_number < super->s_first_data_block || block_number > (super->s_blocks_count + super->s_first_data_block - 1))
+		return -1;	// invalid block number
+	if (ext2_block_status(mount, block_number) != 1)
+		return -2;	// block not allocated
+	block_number -= super->s_first_data_block;	// now a 0-based block number
+	int bg = block_number / super->s_blocks_per_group;
+	ext2_group_desc_t group_desc = ext2_get_group_desc(mount, bg);
+	ext2_free_node(mount, group_desc.bg_block_bitmap, block_number % super->s_blocks_per_group);
+	group_desc.bg_free_blocks_count++;
+	ext2_write_group_desc(mount, bg, &group_desc);
+	super->s_free_blocks_count++;
+	return 0;
+}
+
+int	ext2_resize_inode(vfs_mount_t *mount, u32_t inode_number, u32_t new_size)
+{
+	ext2_inode_t inode;
+	if ( ext2_read_inode(mount, inode_number, &inode) )
+		return -1;
+	ext2_super_block_t *super = mount->super;
+	int current_blocks = (inode.i_size + (1024 << super->s_log_block_size) - 1) >> (10 + super->s_log_block_size);
+	int new_blocks = (new_size + (1024 << super->s_log_block_size) - 1) >> (10 + super->s_log_block_size);
+	if ( new_blocks == current_blocks )
+		return 0;
+
+	// TODO: resize
+	u32_t	block_size = 1024 << super->s_log_block_size;
+	u32_t	pointers_per_block = block_size >> 2;
+	u32_t	*pointer_cache1 = kmalloc(3 * block_size);
+	u32_t	*pointer_cache2 = pointer_cache1 + pointers_per_block;
+	u32_t	*pointer_cache3 = pointer_cache2 + pointers_per_block;
+	u32_t	c1_start, c2_start, c3_start;
+	c1_start = c2_start = c3_start = 0;
+	while (new_blocks < current_blocks)	// delete, decrease current_blocks
+	{
+		current_blocks--;
+		// now delete block number current_blocks
+		
+	}
+
+	while (current_blocks < new_blocks)	// add, increase current_blocks
+	{
+	}
+}
+
+// reserve a node of a inode or block bitmap and mark its entry allocated
+u32_t	ext2_reserve_node(vfs_mount_t *mount, u32_t bitmap_block_num, u32_t bitmap_size)
+{
+	ext2_super_block_t *super = mount->super;
+	u32_t *bitmap = kmalloc(1024 << super->s_log_block_size);
+	int block, max_block = (bitmap_size - 1) / (8192 << super->s_log_block_size) + 1;
+	for (block = 0; block < max_block; block++)
+	{
+		block_read(mount->major, mount->minor, ext2_FSToDiskBlock(bitmap_block_num + block, super),
+			2 << super->s_log_block_size, bitmap);
+		int num, num_max = 256 << super->s_log_block_size;
+		u32_t *block_pointer = bitmap;
+		int done = 0;
+		for (num = 0; num < num_max && !done; num++)
+		{
+			if (*block_pointer != 0xFFFFFFFF)
+			{
+				done = 1;
+				int bit;
+				for (bit = 0; bit < 32; bit++)
+				{
+					if (!(*block_pointer & (1 << bit)))
+					{
+						u32_t node_number = (block * 8192 << super->s_log_block_size) + (num << 5) + bit;
+						if (node_number < bitmap_size)
+						{
+							// found a node, mark it allocated, write the bitmap, return
+							*block_pointer |= (1 << bit);
+							block_write(mount->major, mount->minor,
+								ext2_FSToDiskBlock(bitmap_block_num + block, super),
+								2 << super->s_log_block_size, bitmap);
+							kfree(bitmap);
+							return node_number;
+						}
+						kfree(bitmap);
+						return 0;
+					}
+				}
+			}
+			block_pointer++;
+		}
+	}
+	kfree(bitmap);
+	return 0;
+}
+
+int	ext2_free_node(vfs_mount_t *mount, u32_t bitmap_block_num, u32_t node_number)
+{
+	ext2_super_block_t *super = mount->super;
+	u32_t block_num = node_number >> (13 + super->s_log_block_size);
+	byte *block = kmalloc(1024 << super->s_log_block_size);
+	block_read(mount->major, mount->minor, ext2_FSToDiskBlock(bitmap_block_num + block_num, super),
+		2 << super->s_log_block_size, block);
+	u32_t node_bit_offset = node_number % (8192 << super->s_log_block_size);
+	u32_t node_byte_offset = node_bit_offset >> 3;
+	block[node_byte_offset] &= (0xFF ^ (1 << (node_bit_offset & 0x7)));
+	block_write(mount->major, mount->minor, ext2_FSToDiskBlock(bitmap_block_num + block_num, super),
+		2 << super->s_log_block_size, block);
+	kfree(block);
+	return 0;
+}
+
+// return how many block groups are on the filesystem
+int	ext2_num_block_groups(ext2_super_block_t *super)
+{
+	return (super->s_inodes_count / super->s_inodes_per_group) + 1;
+}
+
+void	ext2_write_super(vfs_mount_t *mount)
+{
+	block_write(mount->major, mount->minor, 2, 2, mount->super);
+}
+
+
+/***************** VFS INTERFACE FUNCTIONS *******************/
+
+
+// mount the superblock of the filesystem and return a pointer to it, if valid
+void	*ext2_mount_super(major_t major, minor_t minor)
+{
+	ext2_super_block_t *super = kmalloc(1024);
+	block_read(major, minor, 2, 2, super);
+	if (super->s_magic != EXT2_MAGIC)			// not an ext2 filesystem
+	{
+		kfree(super);
+		return NULL;
+	}
+	return super;
+}
+
+
+// called when we are unmounting this filesystem mount
+int	ext2_umount_super(vfs_mount_t *mount)
+{
+	ext2_write_super(mount);
+	return kfree(mount->super);			// free memory that the superblock was taking
+}
+
+
+// stat a file, return a structure of info about it
+int	ext2_stat(vfs_mount_t *mount, u32_t inode_number, vfs_stat_t *stat)
+{
+	if (ext2_inode_status(mount, inode_number) != 1)
+		return -1;
+	ext2_inode_t *inode = New(ext2_inode_t);
+	if ( ext2_read_inode(mount, inode_number, inode) )
+	{
+		kfree(inode);
+		return -2;
+	}
+
+	stat->dev = 0;
+	switch(inode->i_mode & EXT2_I_MODE_TYPE_MASK)
+	{
+		case EXT2_I_MODE_FIFO:	stat->type = VFS_FT_FIFO;	break;
+		case EXT2_I_MODE_CHAR:	stat->type = VFS_FT_CHAR;	stat->dev = inode->i_block[0];	break;
+		case EXT2_I_MODE_DIR:	stat->type = VFS_FT_DIR;	break;
+		case EXT2_I_MODE_BLOCK:	stat->type = VFS_FT_BLOCK;	stat->dev = inode->i_block[0];	break;
+		case EXT2_I_MODE_FILE:	stat->type = VFS_FT_FILE;	break;
+		case EXT2_I_MODE_SYM:	stat->type = VFS_FT_SYMLINK;	break;
+		case EXT2_I_MODE_SOCK:	stat->type = VFS_FT_SOCK;	break;
+		default:		stat->type = VFS_FT_UNKNOWN;	break;
+	}
+	stat->size	= inode->i_size;
+	stat->inode	= inode_number;
+	stat->permissions = inode->i_mode & EXT2_I_MODE_ATTR_MASK;
+	stat->uid	= inode->i_uid;
+	stat->gid	= inode->i_gid;
+	stat->atime	= inode->i_atime;
+	stat->mtime	= inode->i_mtime;
+	stat->ctime	= inode->i_ctime;
+	stat->links	= inode->i_links_count;
+	kfree(inode);
+	return 0;
+}
+
+// what is the inode of the root directory?
+u32_t	ext2__get_root_dir_inode(vfs_mount_t *mount)
+{
+	return 2;
+}
+
+
+// VFS interface function to dereference a symbolic link
+int	ext2__link_deref(vfs_mount_t *mount, u32_t link_inode, char *link)
+{
+	ext2_inode_t inode;
+	if (ext2_read_inode(mount, link_inode, &inode))
+		return -1;
+	if ( (inode.i_mode & EXT2_I_MODE_TYPE_MASK) != EXT2_I_MODE_SYM )
+		return -2;
+	if (!inode.i_size)
+		return -4;
+	if (inode.i_size < 61)
+	{
+		memcpy(link, inode.i_block, inode.i_size);
+		link[inode.i_size] = 0;
+		return 0;
+	}
+	else
+	{
+		ext2_open_inode_t *open_inode;
+		if (!(open_inode = ext2_open_inode(mount, link_inode)))
+			return -3;
+		ext2_super_block_t *super = mount->super;
+		void *buffer = kmalloc(1024 << super->s_log_block_size);
+		memset(link, 0, 4096);
+		int copied = 0;
+		while (copied < 4096)
+		{
+			int bytes_read = ext2_read_inode_block(mount, open_inode, buffer);
+			if (bytes_read == 0)
+				break;
+			memcpy(link + copied, buffer, bytes_read);
+			copied += bytes_read;
+		}
+		ext2_close_inode(mount, open_inode);
+		kfree(buffer);
+		return 0;
+	}
+}
+
+// VFS interface function to return the number of free inodes
+int	ext2__free_inodes(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	return super->s_free_inodes_count;
+}
+
+// VFS interface function to return the total number of inodes
+int	ext2__total_inodes(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	return super->s_inodes_count;
+}
+
+// VFS interface function to return the number of free 512-byte blocks
+int	ext2__free_blocks(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	return super->s_free_blocks_count << (1 + super->s_log_block_size);
+}
+
+// VFS interface function to return the total number of 512-byte blocks
+int	ext2__total_blocks(vfs_mount_t *mount)
+{
+	ext2_super_block_t *super = mount->super;
+	return super->s_blocks_count << (1 + super->s_log_block_size);
+}
+
+// VFS interface function to open a directory
+int	ext2__open_dir(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *dir)
+{
+	if (ext2_inode_status(mount, inode_number) != 1)
+		return -1;
+	ext2_open_dir_t *open_dir = ext2_open_dir(mount, inode_number);
+	if (!open_dir)
+		return -2;
+	dir->fs_data = open_dir;
+	return 0;
+}
+
+// VFS interface function to read a directory entry from an open directory
+int	ext2__read_dir(vfs_mount_t *mount, vfs_open_file_t *dir, vfs_dir_entry_t *dentry)
+{
+	ext2_dir_entry_t t_dentry;
+	int status = ext2_dir_read_entry(mount, dir->fs_data, &t_dentry);
+	if (status)
+		return status;
+	memcpy(dentry->name, t_dentry.name, t_dentry.name_length);
+	dentry->name[t_dentry.name_length] = 0;
+	dentry->inode_number = t_dentry.inode;
+	return 0;
+}
+
+// VFS interface function to close an open directory
+int	ext2__close_dir(vfs_mount_t *mount, vfs_open_file_t *dir)
+{
+	return ext2_close_dir(mount, dir->fs_data);
+}
+
+
+// VFS interface function to open a file for reading a byte at a time
+int	ext2__open_file(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file)
+{
+	if (ext2_inode_status(mount, inode_number) != 1)
+		return -1;
+	return 0;
+}
+
+// VFS interface function to read a byte from an open file
+int	ext2__read_file(vfs_mount_t *mount, vfs_open_file_t *open_file)
+{
+	return 0;
+}
+
+// VFS interface function to close a byte-file
+int	ext2__close_file(vfs_mount_t *mount, vfs_open_file_t *open_file)
+{
+	return 0;
+}
+
+
+// VFS interface function to open a file for reading 512-byte blocks at a time
+int	ext2__open_block_file(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file)
+{
+	if (ext2_inode_status(mount, inode_number) != 1)
+		return -1;
+	ext2_open_inode_t *open_inode = ext2_open_inode(mount, inode_number);
+	if (!open_inode)
+		return -2;
+	if ((open_inode->inode.i_mode & EXT2_I_MODE_TYPE_MASK) != EXT2_I_MODE_FILE)
+	{
+		ext2_close_inode(mount, open_inode);
+		return -3;
+	}
+	ext2__open_block_file_t *open_block_file = New(ext2__open_block_file_t);
+	open_block_file->open_inode = open_inode;
+	open_block_file->block = 0;
+	open_file->fs_data = open_block_file;
+	return 0;
+}
+
+// VFS interface function to read a block from an open block file
+// returns the number of bytes read
+int	ext2__read_block_file(vfs_mount_t *mount, vfs_open_file_t *open_file, void *buffer)
+{
+	ext2_super_block_t *super = mount->super;
+	ext2__open_block_file_t *open_block_file = open_file->fs_data;
+	if (ext2_inode_seek(mount, open_block_file->open_inode, ext2_diskToFSBlock(open_block_file->block, super)))
+		return 0;	// EOF
+	u8_t *block = kmalloc(1024 << super->s_log_block_size);
+	u32_t file_position_read = (1024 << super->s_log_block_size) * open_block_file->open_inode->block;
+	u32_t file_position_want = open_block_file->block << 9;
+	u32_t data_offset = file_position_want - file_position_read;
+	int bytes_read = ext2_read_inode_block(mount, open_block_file->open_inode, block);
+	if (bytes_read <= data_offset)
+	{
+		kfree(block);
+		return 0;	// EOF
+	}
+	memcpy(buffer, block + data_offset, min(512, bytes_read - data_offset));
+	kfree(block);
+	open_block_file->block++;
+	return min(512, bytes_read - data_offset);
+}
+
+// VFS interface function to seek to a certain block number of an open block file
+int	ext2__block_file_seek(vfs_mount_t *mount, vfs_open_file_t *open_file, u32_t block_number)
+{
+	ext2__open_block_file_t *open_block_file = open_file->fs_data;
+	return ext2_inode_seek(mount, open_block_file->open_inode, ext2_FSToDiskBlock(block_number, mount->super));
+}
+
+// VFS interface function to close an open block file
+int	ext2__close_block_file(vfs_mount_t *mount, vfs_open_file_t *open_file)
+{
+	ext2__open_block_file_t *open_block_file = open_file->fs_data;
+	ext2_close_inode(mount, open_block_file->open_inode);
+	kfree(open_block_file);
+	return 0;
+}
+
+
+

kernel/fs/ext2/ext2_old.h

@@ -0,0 +1,241 @@
+// ext2.h
+// Author: Josh Holtrop
+// Date: 08/22/04
+// Modified: 12/24/04
+
+#ifndef __HOS_EXT2_H__
+#define __HOS_EXT2_H__ __HOS_EXT2_H__
+
+#include "hos_defines.h"
+#include "fs/devices.h"
+#include "fs/vfs.h"
+
+#define EXT2_MAGIC 0xEF53
+#define EXT2_NAME_LEN 255
+
+#define EXT2_I_MODE_ATTR_MASK	0x0FFF
+#define EXT2_I_MODE_OX		0x0001
+#define EXT2_I_MODE_OW		0x0002
+#define EXT2_I_MODE_OR		0x0004
+#define EXT2_I_MODE_GX		0x0008
+#define EXT2_I_MODE_GW		0x0010
+#define EXT2_I_MODE_GR		0x0020
+#define EXT2_I_MODE_UX		0x0040
+#define EXT2_I_MODE_UW		0x0080
+#define EXT2_I_MODE_UR		0x0100
+#define EXT2_I_MODE_STICKY	0x0200
+#define EXT2_I_MODE_SGID	0x0400
+#define EXT2_I_MODE_SUID	0x0800
+
+#define EXT2_I_MODE_TYPE_MASK	0xF000
+#define EXT2_I_MODE_FIFO	0x1000
+#define EXT2_I_MODE_CHAR	0x2000
+#define EXT2_I_MODE_DIR		0x4000
+#define EXT2_I_MODE_BLOCK	0x6000
+#define EXT2_I_MODE_FILE	0x8000
+#define EXT2_I_MODE_SYM		0xA000
+#define EXT2_I_MODE_SOCK	0xC000
+
+#define EXT2_I_FLAGS_SEC_DEL	0x01
+#define EXT2_I_FLAGS_UNDELETE	0x02
+#define EXT2_I_FLAGS_COMPRESS	0x04
+#define EXT2_I_FLAGS_SYNC	0x08
+#define EXT2_I_FLAGS_IMMUTABLE	0x10
+#define EXT2_I_FLAGS_APPEND	0x20
+#define EXT2_I_FLAGS_NODUMP	0x40
+
+#define EXT2_INODE_BAD_BLOCKS	1
+#define EXT2_INODE_ROOT		2
+#define EXT2_INODE_ACL_INDEX	3
+#define EXT2_INODE_ACL_DATA	4
+#define EXT2_INODE_BOOT_LOADER	5
+#define EXT2_INODE_UNDELETE_DIR	6
+#define EXT2_INODE_AVAIL	11
+
+#define EXT2_FT_UNKNOWN	0
+#define EXT2_FT_FILE	1
+#define EXT2_FT_DIR	2
+#define EXT2_FT_CHAR	3
+#define EXT2_FT_BLOCK	4
+#define EXT2_FT_FIFO	5
+#define EXT2_FT_SOCK	6
+#define EXT2_FT_SYMLINK	7
+#define EXT2_FT_MAX	8
+
+typedef struct
+{
+	u32_t	s_inodes_count;		/* Inodes count */
+	u32_t	s_blocks_count;		/* Blocks count */
+	u32_t	s_r_blocks_count;	/* Reserved blocks count */
+	u32_t	s_free_blocks_count;	/* Free blocks count */
+	u32_t	s_free_inodes_count;	/* Free inodes count */
+	u32_t	s_first_data_block;	/* First Data Block */
+	u32_t	s_log_block_size;	/* Block size: 0->1024, 1->2048, 2->4096 */
+	int	s_log_frag_size;	/* Fragment size */
+	u32_t	s_blocks_per_group;	/* # Blocks per group */
+	u32_t	s_frags_per_group;	/* # Fragments per group */
+	u32_t	s_inodes_per_group;	/* # Inodes per group */
+	u32_t	s_mtime;			/* Mount time */
+	u32_t	s_wtime;			/* Write time */
+	u16_t	s_mnt_count;		/* Mount count */
+	short	s_max_mnt_count;		/* Maximal mount count */
+	u16_t	s_magic;			/* Magic signature */
+	u16_t	s_state;		/* File system state */
+	u16_t	s_errors;		/* Behaviour when detecting errors */
+	u16_t	s_minor_rev_level;	/* minor revision level */
+	u32_t	s_lastcheck;		/* time of last check */
+	u32_t	s_checkinterval;	/* max. time between checks */
+	u32_t	s_creator_os;		/* OS */
+	u32_t	s_rev_level;		/* Revision level */
+	u16_t	s_def_resuid;		/* Default uid for reserved blocks */
+	u16_t	s_def_resgid;		/* Default gid for reserved blocks */
+
+	u32_t	s_reserved[235];
+} ext2_super_block_t;
+
+typedef struct
+{
+	u32_t	bg_block_bitmap;	// Blocks bitmap block
+	u32_t	bg_inode_bitmap;	// Inode bitmap block
+	u32_t	bg_inode_table;		// Inode table block
+	u16_t	bg_free_blocks_count;	// Free blocks count
+	u16_t	bg_free_inodes_count;	// Free Inodes count
+	u16_t	bg_used_dirs_count;	// Directories count
+	u16_t	bg_pad1;
+	u32_t	bg_reserved[3];
+} ext2_group_desc_t;
+
+typedef struct
+{
+	u16_t	i_mode;			// File mode
+	u16_t	i_uid;			// Owner UID
+	u32_t	i_size;			// Size in bytes
+	u32_t	i_atime;		// Access time
+	u32_t	i_ctime;		// Creation time
+	u32_t	i_mtime;		// Modification time
+	u32_t	i_dtime;		// Deletion time
+	u16_t	i_gid;			// Group ID
+	u16_t	i_links_count;		// Links count
+	u32_t	i_blocks;		// Blocks count
+	u32_t	i_flags;		// File flags
+	u32_t	i_reserved1;
+	u32_t	i_block[15];		// Pointers to blocks (12 direct, single, double, triple indirect)
+	u32_t	i_version;		// File version (for NFS)
+	u32_t	i_file_acl;		// File ACL
+	u32_t	i_dir_acl;		// Directory ACL
+	u32_t	i_faddr;		// Fragment address
+	u8_t	i_frag;			// Fragment number
+	u8_t	i_fsize;		// Fragment size
+	u16_t	i_pad1;
+	u32_t	i_reserved2[2];
+} ext2_inode_t;
+
+typedef struct
+{
+	u32_t	inode;			// inode number
+	u16_t	length;			// directory entry length
+	u8_t	name_length;		// name length
+	u8_t	file_type;		// File type
+	char	name[EXT2_NAME_LEN];
+} ext2_dir_entry_t;
+
+typedef struct
+{
+	ext2_inode_t	inode;
+	u32_t	block;
+	u32_t	*block_pointers;
+	u32_t	block_pointers_start;
+} ext2_open_inode_t;
+
+typedef struct
+{
+	ext2_open_inode_t	*open_inode;
+	u32_t	position;
+} ext2_open_dir_t;
+
+typedef struct
+{
+	ext2_open_inode_t	*open_inode;
+	u32_t	position;
+	u32_t	buffer_start;
+	u32_t	buffer_bytes;
+	u8_t	*buffer;
+} ext2__open_file_t;
+
+typedef struct
+{
+	ext2_open_inode_t	*open_inode;
+	u32_t	block;
+} ext2__open_block_file_t;
+
+static inline u32_t	ext2_diskToFSBlock(u32_t block, ext2_super_block_t *super)
+{
+	// convert # of disk blocks to # of filesystem blocks
+	return block >> (super->s_log_block_size + 1);
+}
+
+static inline u32_t	ext2_FSToDiskBlock(u32_t block, ext2_super_block_t *super)
+{
+	// convert # of filesystem blocks to # of disk blocks
+	return block << (super->s_log_block_size + 1);
+}
+
+
+int	ext2_init(int fsID);
+int	ext2_read_inode(vfs_mount_t *mount, u32_t inode, ext2_inode_t *dat);
+int	ext2_write_inode(vfs_mount_t *mount, u32_t inode, ext2_inode_t *dat);
+ext2_group_desc_t	ext2_get_group_desc(vfs_mount_t *mount, u32_t group);
+void	ext2_write_group_desc(vfs_mount_t *mount, u32_t group_num, ext2_group_desc_t *gd);
+ext2_open_inode_t *ext2_open_inode(vfs_mount_t *mount, u32_t inode_number);
+int	ext2_close_inode(vfs_mount_t *mount, ext2_open_inode_t *open_inode);
+int	ext2_read_inode_block(vfs_mount_t *mount, ext2_open_inode_t *open_inode, void *block);
+u32_t	ext2_block_number(vfs_mount_t *mount, ext2_open_inode_t *open_inode);
+int	ext2_inode_seek(vfs_mount_t *mount, ext2_open_inode_t *open_inode, u32_t block_number);
+
+int	ext2_inode_status(vfs_mount_t *mount, u32_t inode_number);
+int	ext2_block_status(vfs_mount_t *mount, u32_t block_number);
+
+u32_t	ext2_alloc_inode(vfs_mount_t *mount);
+int	ext2_free_inode(vfs_mount_t *mount, u32_t inode_number);
+u32_t	ext2_alloc_block(vfs_mount_t *mount);
+int	ext2_free_block(vfs_mount_t *mount, u32_t block_number);
+
+u32_t	ext2_reserve_node(vfs_mount_t *mount, u32_t bitmap_block_num, u32_t bitmap_size);
+int	ext2_free_node(vfs_mount_t *mount, u32_t bitmap_block_num, u32_t node_number);
+int	ext2_num_block_groups(ext2_super_block_t *super);
+void	ext2_write_super(vfs_mount_t *mount);
+
+int	ext2_resize_inode(vfs_mount_t *mount, u32_t inode_number, u32_t new_size);
+
+ext2_open_dir_t *ext2_open_dir(vfs_mount_t *mount, u32_t inode_number);
+int	ext2_dir_read_entry(vfs_mount_t *mount, ext2_open_dir_t *open_dir, ext2_dir_entry_t *dentry);
+int	ext2_close_dir(vfs_mount_t *mount, ext2_open_dir_t *open_dir);
+int	ext2_dir_lookup(vfs_mount_t *mount, u32_t dir_inode, char *fileName, ext2_dir_entry_t *direntry);
+
+
+void	*ext2_mount_super(major_t major, minor_t minor);
+int	ext2_umount_super(vfs_mount_t *mount);
+int	ext2_stat(vfs_mount_t *mount, u32_t inode_number, vfs_stat_t *stat);
+u32_t	ext2__get_root_dir_inode(vfs_mount_t *mount);
+int	ext2__link_deref(vfs_mount_t *mount, u32_t link_inode, char *link);
+int	ext2__free_inodes(vfs_mount_t *mount);
+int	ext2__total_inodes(vfs_mount_t *mount);
+int	ext2__free_blocks(vfs_mount_t *mount);
+int	ext2__total_blocks(vfs_mount_t *mount);
+
+
+int	ext2__open_dir(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *dir);
+int	ext2__read_dir(vfs_mount_t *mount, vfs_open_file_t *dir, vfs_dir_entry_t *dentry);
+int	ext2__close_dir(vfs_mount_t *mount, vfs_open_file_t *dir);
+
+int	ext2__open_file(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file);
+int	ext2__read_file(vfs_mount_t *mount, vfs_open_file_t *open_file);
+int	ext2__close_file(vfs_mount_t *mount, vfs_open_file_t *open_file);
+
+int	ext2__open_block_file(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file);
+int	ext2__read_block_file(vfs_mount_t *mount, vfs_open_file_t *open_file, void *buffer);
+int	ext2__block_file_seek(vfs_mount_t *mount, vfs_open_file_t *open_file, u32_t block_number);
+int	ext2__close_block_file(vfs_mount_t *mount, vfs_open_file_t *open_file);
+
+#endif
+