/*
* ext4_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 _EXT4_I
#define _EXT4_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;
/* data type for file logical block number */
typedef __u32 ext4_lblk_t;
/* data type for block group number */
typedef unsigned int ext4_group_t;
/*
* storage for cached extent
*/
struct ext4_ext_cache {
ext4_fsblk_t ec_start;
ext4_lblk_t ec_block;
__u32 ec_len; /* must be 32bit to return holes */
__u32 ec_type;
};
/*
* fourth extended file system inode data in memory
*/
struct ext4_inode_info {
__le32 i_data[15]; /* unconverted */
__u32 i_flags;
ext4_fsblk_t i_file_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.
*/
ext4_group_t i_block_group;
__u32 i_state; /* Dynamic state flags for ext4 */
ext4_lblk_t i_dir_start_lookup;
#ifdef CONFIG_EXT4_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_EXT4_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;
/*
* i_data_sem 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 i_data_sem.
*/
struct rw_semaphore i_data_sem;
struct inode vfs_inode;
struct jbd2_inode jinode;
struct ext4_ext_cache i_cached_extent;
/*
* File creation time. Its function is same as that of
* struct timespec i_{a,c,m}time in the generic inode.
*/
struct timespec i_crtime;
/* mballoc */
struct list_head i_prealloc_list;
spinlock_t i_prealloc_lock;
/* ialloc */
ext4_group_t i_last_alloc_group;
/* allocation reservation info for delalloc */
unsigned int i_reserved_data_blocks;
unsigned int i_reserved_meta_blocks;
unsigned int i_allocated_meta_blocks;
unsigned short i_delalloc_reserved_flag;
/* on-disk additional length */
__u16 i_extra_isize;
spinlock_t i_block_reservation_lock;
};
#endif /* _EXT4_I */
