fs/ext4/ext4_sb.h

   1 /*
   2  *  ext4_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 _EXT4_SB
  17 #define _EXT4_SB
  18
  19 #ifdef __KERNEL__
  20 #include <linux/timer.h>
  21 #include <linux/wait.h>
  22 #include <linux/blockgroup_lock.h>
  23 #include <linux/percpu_counter.h>
  24 #endif
  25 #include <linux/rbtree.h>
  26
  27 /*
  28  * fourth extended-fs super-block data in memory
  29  */
  30 struct ext4_sb_info {
  31         unsigned long s_desc_size;      /* Size of a group descriptor in bytes */
  32         unsigned long s_inodes_per_block;/* Number of inodes per block */
  33         unsigned long s_blocks_per_group;/* Number of blocks in a group */
  34         unsigned long s_inodes_per_group;/* Number of inodes in a group */
  35         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
  36         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
  37         unsigned long s_desc_per_block; /* Number of group descriptors per block */
  38         ext4_group_t s_groups_count;    /* Number of groups in the fs */
  39         unsigned long s_overhead_last;  /* Last calculated overhead */
  40         unsigned long s_blocks_last;    /* Last seen block count */
  41         loff_t s_bitmap_maxbytes;       /* max bytes for bitmap files */
  42         struct buffer_head * s_sbh;     /* Buffer containing the super block */
  43         struct ext4_super_block *s_es;  /* Pointer to the super block in the buffer */
  44         struct buffer_head **s_group_desc;
  45         unsigned long  s_mount_opt;
  46         ext4_fsblk_t s_sb_block;
  47         uid_t s_resuid;
  48         gid_t s_resgid;
  49         unsigned short s_mount_state;
  50         unsigned short s_pad;
  51         int s_addr_per_block_bits;
  52         int s_desc_per_block_bits;
  53         int s_inode_size;
  54         int s_first_ino;
  55         unsigned int s_inode_readahead_blks;
  56         spinlock_t s_next_gen_lock;
  57         u32 s_next_generation;
  58         u32 s_hash_seed[4];
  59         int s_def_hash_version;
  60         int s_hash_unsigned;    /* 3 if hash should be signed, 0 if not */
  61         struct percpu_counter s_freeblocks_counter;
  62         struct percpu_counter s_freeinodes_counter;
  63         struct percpu_counter s_dirs_counter;
  64         struct percpu_counter s_dirtyblocks_counter;
  65         struct blockgroup_lock *s_blockgroup_lock;
  66         struct proc_dir_entry *s_proc;
  67         struct kobject s_kobj;
  68         struct completion s_kobj_unregister;
  69
  70         /* Journaling */
  71         struct inode *s_journal_inode;
  72         struct journal_s *s_journal;
  73         struct list_head s_orphan;
  74         unsigned long s_commit_interval;
  75         u32 s_max_batch_time;
  76         u32 s_min_batch_time;
  77         struct block_device *journal_bdev;
  78 #ifdef CONFIG_JBD2_DEBUG
  79         struct timer_list turn_ro_timer;        /* For turning read-only (crash simulation) */
  80         wait_queue_head_t ro_wait_queue;        /* For people waiting for the fs to go read-only */
  81 #endif
  82 #ifdef CONFIG_QUOTA
  83         char *s_qf_names[MAXQUOTAS];            /* Names of quota files with journalled quota */
  84         int s_jquota_fmt;                       /* Format of quota to use */
  85 #endif
  86         unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
  87
  88 #ifdef EXTENTS_STATS
  89         /* ext4 extents stats */
  90         unsigned long s_ext_min;
  91         unsigned long s_ext_max;
  92         unsigned long s_depth_max;
  93         spinlock_t s_ext_stats_lock;
  94         unsigned long s_ext_blocks;
  95         unsigned long s_ext_extents;
  96 #endif
  97
  98         /* for buddy allocator */
  99         struct ext4_group_info ***s_group_info;
 100         struct inode *s_buddy_cache;
 101         long s_blocks_reserved;
 102         spinlock_t s_reserve_lock;
 103         spinlock_t s_md_lock;
 104         tid_t s_last_transaction;
 105         unsigned short *s_mb_offsets;
 106         unsigned int *s_mb_maxs;
 107
 108         /* tunables */
 109         unsigned long s_stripe;
 110         unsigned int s_mb_stream_request;
 111         unsigned int s_mb_max_to_scan;
 112         unsigned int s_mb_min_to_scan;
 113         unsigned int s_mb_stats;
 114         unsigned int s_mb_order2_reqs;
 115         unsigned int s_mb_group_prealloc;
 116         /* where last allocation was done - for stream allocation */
 117         unsigned long s_mb_last_group;
 118         unsigned long s_mb_last_start;
 119
 120         /* history to debug policy */
 121         struct ext4_mb_history *s_mb_history;
 122         int s_mb_history_cur;
 123         int s_mb_history_max;
 124         int s_mb_history_num;
 125         spinlock_t s_mb_history_lock;
 126         int s_mb_history_filter;
 127
 128         /* stats for buddy allocator */
 129         spinlock_t s_mb_pa_lock;
 130         atomic_t s_bal_reqs;    /* number of reqs with len > 1 */
 131         atomic_t s_bal_success; /* we found long enough chunks */
 132         atomic_t s_bal_allocated;       /* in blocks */
 133         atomic_t s_bal_ex_scanned;      /* total extents scanned */
 134         atomic_t s_bal_goals;   /* goal hits */
 135         atomic_t s_bal_breaks;  /* too long searches */
 136         atomic_t s_bal_2orders; /* 2^order hits */
 137         spinlock_t s_bal_lock;
 138         unsigned long s_mb_buddies_generated;
 139         unsigned long long s_mb_generation_time;
 140         atomic_t s_mb_lost_chunks;
 141         atomic_t s_mb_preallocated;
 142         atomic_t s_mb_discarded;
 143
 144         /* locality groups */
 145         struct ext4_locality_group *s_locality_groups;
 146
 147         /* for write statistics */
 148         unsigned long s_sectors_written_start;
 149         u64 s_kbytes_written;
 150
 151         unsigned int s_log_groups_per_flex;
 152         struct flex_groups *s_flex_groups;
 153 };
 154
 155 static inline spinlock_t *
 156 sb_bgl_lock(struct ext4_sb_info *sbi, unsigned int block_group)
 157 {
 158         return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
 159 }
 160
 161 #endif  /* _EXT4_SB */