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/*
* linux/include/linux/ext4_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_EXT4_FS_I
#define _LINUX_EXT4_FS_I
#include <linux/rwsem.h>
#include <linux/rbtree.h>
#include <linux/seqlock.h>
#include <linux/mutex.h>
/* data type for block offset of block group */
typedef int ext4_grpblk_t;
/* data type for filesystem-wide blocks number */
typedef unsigned long long ext4_fsblk_t;
struct ext4_reserve_window {
ext4_fsblk_t _rsv_start; /* First byte reserved */
ext4_fsblk_t _rsv_end; /* Last byte reserved or 0 */
};
struct ext4_reserve_window_node {
struct rb_node rsv_node;
__u32 rsv_goal_size;
__u32 rsv_alloc_hit;
struct ext4_reserve_window rsv_window;
};
struct ext4_block_alloc_info {
/* information about reservation window */
struct ext4_reserve_window_node rsv_window_node;
/*
* was i_next_alloc_block in ext4_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 ext4_inode_info
* is the *physical* companion to i_next_alloc_block.
* it the 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.
*/
ext4_fsblk_t last_alloc_physical_block;
};
#define rsv_start rsv_window._rsv_start
#define rsv_end rsv_window._rsv_end
/*
* storage for cached extent
*/
struct ext4_ext_cache {
ext4_fsblk_t ec_start;
__u32 ec_block;
__u32 ec_len; /* must be 32bit to return holes */
__u32 ec_type;
};
/*
* third extended file system inode data in memory
*/
struct ext4_inode_info {
__le32 i_data[15]; /* unconverted */
__u32 i_flags;
#ifdef EXT4_FRAGMENTS
__u32 i_faddr;
__u8 i_frag_no;
__u8 i_frag_size;
#endif
ext4_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 ext4 */
/* block reservation info */
struct ext4_block_alloc_info *i_block_alloc_info;
__u32 i_dir_start_lookup;
#ifdef CONFIG_EXT4DEV_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_EXT4DEV_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 ext4_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 ext4_get_block (growth) and ext4_truncate (shrinkth).
*/
loff_t i_disksize;
/* on-disk additional length */
__u16 i_extra_isize;
/*
* truncate_mutex is for serialising ext4_truncate() against
* ext4_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
* ext4 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;
struct inode vfs_inode;
unsigned long i_ext_generation;
struct ext4_ext_cache i_cached_extent;
};
#endif /* _LINUX_EXT4_FS_I */
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