release/src-rt-6.x.4708/linux/linux-2.6.36/fs/btrfs/btrfs_inode.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #ifndef __BTRFS_I__
  20 #define __BTRFS_I__
  21
  22 #include "extent_map.h"
  23 #include "extent_io.h"
  24 #include "ordered-data.h"
  25
  26 /* in memory btrfs inode */
  27 struct btrfs_inode {
  28         /* which subvolume this inode belongs to */
  29         struct btrfs_root *root;
  30
  31         /* key used to find this inode on disk.  This is used by the code
  32          * to read in roots of subvolumes
  33          */
  34         struct btrfs_key location;
  35
  36         /* the extent_tree has caches of all the extent mappings to disk */
  37         struct extent_map_tree extent_tree;
  38
  39         /* the io_tree does range state (DIRTY, LOCKED etc) */
  40         struct extent_io_tree io_tree;
  41
  42         /* special utility tree used to record which mirrors have already been
  43          * tried when checksums fail for a given block
  44          */
  45         struct extent_io_tree io_failure_tree;
  46
  47         /* held while logging the inode in tree-log.c */
  48         struct mutex log_mutex;
  49
  50         /* used to order data wrt metadata */
  51         struct btrfs_ordered_inode_tree ordered_tree;
  52
  53         /* for keeping track of orphaned inodes */
  54         struct list_head i_orphan;
  55
  56         /* list of all the delalloc inodes in the FS.  There are times we need
  57          * to write all the delalloc pages to disk, and this list is used
  58          * to walk them all.
  59          */
  60         struct list_head delalloc_inodes;
  61
  62         /*
  63          * list for tracking inodes that must be sent to disk before a
  64          * rename or truncate commit
  65          */
  66         struct list_head ordered_operations;
  67
  68         /* node for the red-black tree that links inodes in subvolume root */
  69         struct rb_node rb_node;
  70
  71         /* the space_info for where this inode's data allocations are done */
  72         struct btrfs_space_info *space_info;
  73
  74         /* full 64 bit generation number, struct vfs_inode doesn't have a big
  75          * enough field for this.
  76          */
  77         u64 generation;
  78
  79         /* sequence number for NFS changes */
  80         u64 sequence;
  81
  82         /*
  83          * transid of the trans_handle that last modified this inode
  84          */
  85         u64 last_trans;
  86
  87         /*
  88          * log transid when this inode was last modified
  89          */
  90         u64 last_sub_trans;
  91
  92         /*
  93          * transid that last logged this inode
  94          */
  95         u64 logged_trans;
  96
  97         /* total number of bytes pending delalloc, used by stat to calc the
  98          * real block usage of the file
  99          */
 100         u64 delalloc_bytes;
 101
 102         /* total number of bytes that may be used for this inode for
 103          * delalloc
 104          */
 105         u64 reserved_bytes;
 106
 107         /*
 108          * the size of the file stored in the metadata on disk.  data=ordered
 109          * means the in-memory i_size might be larger than the size on disk
 110          * because not all the blocks are written yet.
 111          */
 112         u64 disk_i_size;
 113
 114         /* flags field from the on disk inode */
 115         u32 flags;
 116
 117         /*
 118          * if this is a directory then index_cnt is the counter for the index
 119          * number for new files that are created
 120          */
 121         u64 index_cnt;
 122
 123         /* the start of block group preferred for allocations. */
 124         u64 block_group;
 125
 126         /* the fsync log has some corner cases that mean we have to check
 127          * directories to see if any unlinks have been done before
 128          * the directory was logged.  See tree-log.c for all the
 129          * details
 130          */
 131         u64 last_unlink_trans;
 132
 133         /*
 134          * Counters to keep track of the number of extent item's we may use due
 135          * to delalloc and such.  outstanding_extents is the number of extent
 136          * items we think we'll end up using, and reserved_extents is the number
 137          * of extent items we've reserved metadata for.
 138          */
 139         spinlock_t accounting_lock;
 140         atomic_t outstanding_extents;
 141         int reserved_extents;
 142
 143         /*
 144          * ordered_data_close is set by truncate when a file that used
 145          * to have good data has been truncated to zero.  When it is set
 146          * the btrfs file release call will add this inode to the
 147          * ordered operations list so that we make sure to flush out any
 148          * new data the application may have written before commit.
 149          *
 150          * yes, its silly to have a single bitflag, but we might grow more
 151          * of these.
 152          */
 153         unsigned ordered_data_close:1;
 154         unsigned orphan_meta_reserved:1;
 155         unsigned dummy_inode:1;
 156
 157         /*
 158          * always compress this one file
 159          */
 160         unsigned force_compress:1;
 161
 162         struct inode vfs_inode;
 163 };
 164
 165 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
 166 {
 167         return container_of(inode, struct btrfs_inode, vfs_inode);
 168 }
 169
 170 static inline void btrfs_i_size_write(struct inode *inode, u64 size)
 171 {
 172         i_size_write(inode, size);
 173         BTRFS_I(inode)->disk_i_size = size;
 174 }
 175
 176 #endif