include/linux/ext2_fs_sb.h

   1 /*
   2  *  linux/include/linux/ext2_fs_sb.h
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/include/linux/minix_fs_sb.h
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  */
  15
  16 #ifndef _LINUX_EXT2_FS_SB
  17 #define _LINUX_EXT2_FS_SB
  18
  19 #include <linux/blockgroup_lock.h>
  20 #include <linux/percpu_counter.h>
  21 #include <linux/rbtree.h>
  22
  23 /* XXX Here for now... not interested in restructing headers JUST now */
  24
  25 /* data type for block offset of block group */
  26 typedef int ext2_grpblk_t;
  27
  28 /* data type for filesystem-wide blocks number */
  29 typedef unsigned long ext2_fsblk_t;
  30
  31 #define E2FSBLK "%lu"
  32
  33 struct ext2_reserve_window {
  34         ext2_fsblk_t            _rsv_start;     /* First byte reserved */
  35         ext2_fsblk_t            _rsv_end;       /* Last byte reserved or 0 */
  36 };
  37
  38 struct ext2_reserve_window_node {
  39         struct rb_node          rsv_node;
  40         __u32                   rsv_goal_size;
  41         __u32                   rsv_alloc_hit;
  42         struct ext2_reserve_window      rsv_window;
  43 };
  44
  45 struct ext2_block_alloc_info {
  46         /* information about reservation window */
  47         struct ext2_reserve_window_node rsv_window_node;
  48         /*
  49          * was i_next_alloc_block in ext2_inode_info
  50          * is the logical (file-relative) number of the
  51          * most-recently-allocated block in this file.
  52          * We use this for detecting linearly ascending allocation requests.
  53          */
  54         __u32                   last_alloc_logical_block;
  55         /*
  56          * Was i_next_alloc_goal in ext2_inode_info
  57          * is the *physical* companion to i_next_alloc_block.
  58          * it the the physical block number of the block which was most-recentl
  59          * allocated to this file.  This give us the goal (target) for the next
  60          * allocation when we detect linearly ascending requests.
  61          */
  62         ext2_fsblk_t            last_alloc_physical_block;
  63 };
  64
  65 #define rsv_start rsv_window._rsv_start
  66 #define rsv_end rsv_window._rsv_end
  67
  68 /*
  69  * second extended-fs super-block data in memory
  70  */
  71 struct ext2_sb_info {
  72         unsigned long s_frag_size;      /* Size of a fragment in bytes */
  73         unsigned long s_frags_per_block;/* Number of fragments per block */
  74         unsigned long s_inodes_per_block;/* Number of inodes per block */
  75         unsigned long s_frags_per_group;/* Number of fragments in a group */
  76         unsigned long s_blocks_per_group;/* Number of blocks in a group */
  77         unsigned long s_inodes_per_group;/* Number of inodes in a group */
  78         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
  79         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
  80         unsigned long s_desc_per_block; /* Number of group descriptors per block */
  81         unsigned long s_groups_count;   /* Number of groups in the fs */
  82         unsigned long s_overhead_last;  /* Last calculated overhead */
  83         unsigned long s_blocks_last;    /* Last seen block count */
  84         struct buffer_head * s_sbh;     /* Buffer containing the super block */
  85         struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
  86         struct buffer_head ** s_group_desc;
  87         unsigned long  s_mount_opt;
  88         unsigned long s_sb_block;
  89         uid_t s_resuid;
  90         gid_t s_resgid;
  91         unsigned short s_mount_state;
  92         unsigned short s_pad;
  93         int s_addr_per_block_bits;
  94         int s_desc_per_block_bits;
  95         int s_inode_size;
  96         int s_first_ino;
  97         spinlock_t s_next_gen_lock;
  98         u32 s_next_generation;
  99         unsigned long s_dir_count;
 100         u8 *s_debts;
 101         struct percpu_counter s_freeblocks_counter;
 102         struct percpu_counter s_freeinodes_counter;
 103         struct percpu_counter s_dirs_counter;
 104         struct blockgroup_lock *s_blockgroup_lock;
 105         /* root of the per fs reservation window tree */
 106         spinlock_t s_rsv_window_lock;
 107         struct rb_root s_rsv_window_root;
 108         struct ext2_reserve_window_node s_rsv_window_head;
 109         /*
 110          * s_lock protects against concurrent modifications of s_mount_state,
 111          * s_blocks_last, s_overhead_last and the content of superblock's
 112          * buffer pointed to by sbi->s_es.
 113          *
 114          * Note: It is used in ext2_show_options() to provide a consistent view
 115          * of the mount options.
 116          */
 117         spinlock_t s_lock;
 118 };
 119
 120 static inline spinlock_t *
 121 sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)
 122 {
 123         return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
 124 }
 125
 126 #endif  /* _LINUX_EXT2_FS_SB */