reactos/drivers/filesystems/ext2/inc/linux/ext3_fs_i.h

/*
 *  linux/include/linux/ext3_fs_i.h
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/include/linux/minix_fs_i.h
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#ifndef _LINUX_EXT3_FS_I
#define _LINUX_EXT3_FS_I

#include <linux/rbtree.h>

/* data type for block offset of block group */
typedef int ext3_grpblk_t;
typedef int ext4_grpblk_t;

/* data type for filesystem-wide blocks number */
typedef unsigned long long ext3_fsblk_t;
typedef unsigned long long ext4_fsblk_t;

/* data type for file logical block number */
typedef __u32 ext3_lblk_t;
typedef __u32 ext4_lblk_t;

/* data type for block group number */
typedef unsigned int ext3_group_t;
typedef unsigned int ext4_group_t;

#define E3FSBLK "%lu"

struct ext3_reserve_window {
    ext3_fsblk_t	_rsv_start;	/* First byte reserved */
    ext3_fsblk_t	_rsv_end;	/* Last byte reserved or 0 */
};

struct ext3_reserve_window_node {
    struct rb_node		rsv_node;
    __u32			rsv_goal_size;
    __u32			rsv_alloc_hit;
    struct ext3_reserve_window	rsv_window;
};

struct ext3_block_alloc_info {
    /* information about reservation window */
    struct ext3_reserve_window_node	rsv_window_node;
    /*
     * was i_next_alloc_block in ext3_inode_info
     * is the logical (file-relative) number of the
     * most-recently-allocated block in this file.
     * We use this for detecting linearly ascending allocation requests.
     */
    __u32                   last_alloc_logical_block;
    /*
     * Was i_next_alloc_goal in ext3_inode_info
     * is the *physical* companion to i_next_alloc_block.
     * it the physical block number of the block which was most-recentl
     * allocated to this file.  This give us the goal (target) for the next
     * allocation when we detect linearly ascending requests.
     */
    ext3_fsblk_t		last_alloc_physical_block;
};

#define rsv_start rsv_window._rsv_start
#define rsv_end rsv_window._rsv_end

/*
 * third extended file system inode data in memory
 */
struct ext3_inode_info {
    __le32	i_data[15];	/* unconverted */
    __u32	i_flags;
#ifdef EXT3_FRAGMENTS
    __u32	i_faddr;
    __u8	i_frag_no;
    __u8	i_frag_size;
#endif
    ext3_fsblk_t	i_file_acl;
    __u32	i_dir_acl;
    __u32	i_dtime;

    /*
     * i_block_group is the number of the block group which contains
     * this file's inode.  Constant across the lifetime of the inode,
     * it is ued for making block allocation decisions - we try to
     * place a file's data blocks near its inode block, and new inodes
     * near to their parent directory's inode.
     */
    __u32	i_block_group;
    __u32	i_state;		/* Dynamic state flags for ext3 */

    /* block reservation info */
    struct ext3_block_alloc_info *i_block_alloc_info;

    __u32	i_dir_start_lookup;
#ifdef CONFIG_EXT3_FS_XATTR
    /*
     * Extended attributes can be read independently of the main file
     * data. Taking i_mutex even when reading would cause contention
     * between readers of EAs and writers of regular file data, so
     * instead we synchronize on xattr_sem when reading or changing
     * EAs.
     */
    struct rw_semaphore xattr_sem;
#endif
#ifdef CONFIG_EXT3_FS_POSIX_ACL
    struct posix_acl	*i_acl;
    struct posix_acl	*i_default_acl;
#endif

    struct list_head i_orphan;	/* unlinked but open inodes */

    /*
     * i_disksize keeps track of what the inode size is ON DISK, not
     * in memory.  During truncate, i_size is set to the new size by
     * the VFS prior to calling ext3_truncate(), but the filesystem won't
     * set i_disksize to 0 until the truncate is actually under way.
     *
     * The intent is that i_disksize always represents the blocks which
     * are used by this file.  This allows recovery to restart truncate
     * on orphans if we crash during truncate.  We actually write i_disksize
     * into the on-disk inode when writing inodes out, instead of i_size.
     *
     * The only time when i_disksize and i_size may be different is when
     * a truncate is in progress.  The only things which change i_disksize
     * are ext3_get_block (growth) and ext3_truncate (shrinkth).
     */
    loff_t	i_disksize;

    /* on-disk additional length */
    __u16 i_extra_isize;

#if 0
    /*
     * truncate_mutex is for serialising ext3_truncate() against
     * ext3_getblock().  In the 2.4 ext2 design, great chunks of inode's
     * data tree are chopped off during truncate. We can't do that in
     * ext3 because whenever we perform intermediate commits during
     * truncate, the inode and all the metadata blocks *must* be in a
     * consistent state which allows truncation of the orphans to restart
     * during recovery.  Hence we must fix the get_block-vs-truncate race
     * by other means, so we have truncate_mutex.
     */
    struct mutex truncate_mutex;
#endif
    struct inode vfs_inode;
};

#endif	/* _LINUX_EXT3_FS_I */