kernel-ark/include/linux/ext3_fs_i.h
Arjan van de Ven 9746151861 [PATCH] convert ext3's truncate_sem to a mutex
ext3's truncate_sem is always released in the same function it's taken
and it otherwise is a mutex as well..

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:14 -08:00

140 lines
4.2 KiB
C

/*
* 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/rwsem.h>
#include <linux/rbtree.h>
#include <linux/seqlock.h>
#include <linux/mutex.h>
struct ext3_reserve_window {
__u32 _rsv_start; /* First byte reserved */
__u32 _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 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.
*/
__u32 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
__u32 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;
/*
* 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;
struct inode vfs_inode;
};
#endif /* _LINUX_EXT3_FS_I */