+
+/*
+ * run-time mount flags
+ */
+#define EXT4_MF_MNTDIR_SAMPLED 0x0001
+#define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */
+
+/*
+ * fourth extended-fs super-block data in memory
+ */
+struct ext4_sb_info {
+ unsigned long s_desc_size; /* Size of a group descriptor in bytes */
+ unsigned long s_inodes_per_block;/* Number of inodes per block */
+ unsigned long s_blocks_per_group;/* Number of blocks in a group */
+ unsigned long s_inodes_per_group;/* Number of inodes in a group */
+ unsigned long s_itb_per_group; /* Number of inode table blocks per group */
+ unsigned long s_gdb_count; /* Number of group descriptor blocks */
+ unsigned long s_desc_per_block; /* Number of group descriptors per block */
+ ext4_group_t s_groups_count; /* Number of groups in the fs */
+ ext4_group_t s_blockfile_groups;/* Groups acceptable for non-extent files */
+ unsigned long s_overhead_last; /* Last calculated overhead */
+ unsigned long s_blocks_last; /* Last seen block count */
+ loff_t s_bitmap_maxbytes; /* max bytes for bitmap files */
+ struct buffer_head * s_sbh; /* Buffer containing the super block */
+ struct ext4_super_block *s_es; /* Pointer to the super block in the buffer */
+ struct buffer_head **s_group_desc;
+ unsigned int s_mount_opt;
+ unsigned int s_mount_flags;
+ ext4_fsblk_t s_sb_block;
+ uid_t s_resuid;
+ gid_t s_resgid;
+ unsigned short s_mount_state;
+ unsigned short s_pad;
+ int s_addr_per_block_bits;
+ int s_desc_per_block_bits;
+ int s_inode_size;
+ int s_first_ino;
+ unsigned int s_inode_readahead_blks;
+ unsigned int s_inode_goal;
+ spinlock_t s_next_gen_lock;
+ u32 s_next_generation;
+ u32 s_hash_seed[4];
+ int s_def_hash_version;
+ int s_hash_unsigned; /* 3 if hash should be signed, 0 if not */
+ struct percpu_counter s_freeblocks_counter;
+ struct percpu_counter s_freeinodes_counter;
+ struct percpu_counter s_dirs_counter;
+ struct percpu_counter s_dirtyblocks_counter;
+ struct blockgroup_lock *s_blockgroup_lock;
+ struct proc_dir_entry *s_proc;
+ struct kobject s_kobj;
+ struct completion s_kobj_unregister;
+
+ /* Journaling */
+ struct inode *s_journal_inode;
+ struct journal_s *s_journal;
+ struct list_head s_orphan;
+ struct mutex s_orphan_lock;
+ struct mutex s_resize_lock;
+ unsigned long s_commit_interval;
+ u32 s_max_batch_time;
+ u32 s_min_batch_time;
+ struct block_device *journal_bdev;
+#ifdef CONFIG_JBD2_DEBUG
+ struct timer_list turn_ro_timer; /* For turning read-only (crash simulation) */
+ wait_queue_head_t ro_wait_queue; /* For people waiting for the fs to go read-only */
+#endif
+#ifdef CONFIG_QUOTA
+ char *s_qf_names[MAXQUOTAS]; /* Names of quota files with journalled quota */
+ int s_jquota_fmt; /* Format of quota to use */
+#endif
+ unsigned int s_want_extra_isize; /* New inodes should reserve # bytes */
+ struct rb_root system_blks;
+
+#ifdef EXTENTS_STATS
+ /* ext4 extents stats */
+ unsigned long s_ext_min;
+ unsigned long s_ext_max;
+ unsigned long s_depth_max;
+ spinlock_t s_ext_stats_lock;
+ unsigned long s_ext_blocks;
+ unsigned long s_ext_extents;
+#endif
+
+ /* for buddy allocator */
+ struct ext4_group_info ***s_group_info;
+ struct inode *s_buddy_cache;
+ long s_blocks_reserved;
+ spinlock_t s_reserve_lock;
+ spinlock_t s_md_lock;
+ tid_t s_last_transaction;
+ unsigned short *s_mb_offsets;
+ unsigned int *s_mb_maxs;
+
+ /* tunables */
+ unsigned long s_stripe;
+ unsigned int s_mb_stream_request;
+ unsigned int s_mb_max_to_scan;
+ unsigned int s_mb_min_to_scan;
+ unsigned int s_mb_stats;
+ unsigned int s_mb_order2_reqs;
+ unsigned int s_mb_group_prealloc;
+ unsigned int s_max_writeback_mb_bump;
+ /* where last allocation was done - for stream allocation */
+ unsigned long s_mb_last_group;
+ unsigned long s_mb_last_start;
+
+ /* stats for buddy allocator */
+ spinlock_t s_mb_pa_lock;
+ atomic_t s_bal_reqs; /* number of reqs with len > 1 */
+ atomic_t s_bal_success; /* we found long enough chunks */
+ atomic_t s_bal_allocated; /* in blocks */
+ atomic_t s_bal_ex_scanned; /* total extents scanned */
+ atomic_t s_bal_goals; /* goal hits */
+ atomic_t s_bal_breaks; /* too long searches */
+ atomic_t s_bal_2orders; /* 2^order hits */
+ spinlock_t s_bal_lock;
+ unsigned long s_mb_buddies_generated;
+ unsigned long long s_mb_generation_time;
+ atomic_t s_mb_lost_chunks;
+ atomic_t s_mb_preallocated;
+ atomic_t s_mb_discarded;
+ atomic_t s_lock_busy;
+
+ /* locality groups */
+ struct ext4_locality_group __percpu *s_locality_groups;
+
+ /* for write statistics */
+ unsigned long s_sectors_written_start;
+ u64 s_kbytes_written;
+
+ unsigned int s_log_groups_per_flex;
+ struct flex_groups *s_flex_groups;
+
+ /* workqueue for dio unwritten */
+ struct workqueue_struct *dio_unwritten_wq;
+};
+