[deliverable/linux.git] / fs / gfs2 / incore.h

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License version 2.
 */

#ifndef __INCORE_DOT_H__
#define __INCORE_DOT_H__

#include <linux/fs.h>
#include <linux/kobject.h>
#include <linux/workqueue.h>
#include <linux/dlm.h>
#include <linux/buffer_head.h>
#include <linux/rcupdate.h>
#include <linux/rculist_bl.h>
#include <linux/completion.h>
#include <linux/rbtree.h>
#include <linux/ktime.h>
#include <linux/percpu.h>

#define DIO_WAIT        0x00000010
#define DIO_METADATA    0x00000020

struct gfs2_log_operations;
struct gfs2_bufdata;
struct gfs2_holder;
struct gfs2_glock;
struct gfs2_quota_data;
struct gfs2_trans;
struct gfs2_ail;
struct gfs2_jdesc;
struct gfs2_sbd;
struct lm_lockops;

typedef void (*gfs2_glop_bh_t) (struct gfs2_glock *gl, unsigned int ret);

struct gfs2_log_header_host {
        u64 lh_sequence;        /* Sequence number of this transaction */
        u32 lh_flags;           /* GFS2_LOG_HEAD_... */
        u32 lh_tail;            /* Block number of log tail */
        u32 lh_blkno;
        u32 lh_hash;
};

/*
 * Structure of operations that are associated with each
 * type of element in the log.
 */

struct gfs2_log_operations {
        void (*lo_add) (struct gfs2_sbd *sdp, struct gfs2_bufdata *bd);
        void (*lo_before_commit) (struct gfs2_sbd *sdp);
        void (*lo_after_commit) (struct gfs2_sbd *sdp, struct gfs2_ail *ai);
        void (*lo_before_scan) (struct gfs2_jdesc *jd,
                                struct gfs2_log_header_host *head, int pass);
        int (*lo_scan_elements) (struct gfs2_jdesc *jd, unsigned int start,
                                 struct gfs2_log_descriptor *ld, __be64 *ptr,
                                 int pass);
        void (*lo_after_scan) (struct gfs2_jdesc *jd, int error, int pass);
        const char *lo_name;
};

#define GBF_FULL 1

struct gfs2_bitmap {
        struct buffer_head *bi_bh;
        char *bi_clone;
        unsigned long bi_flags;
        u32 bi_offset;
        u32 bi_start;
        u32 bi_len;
};

struct gfs2_rgrpd {
        struct rb_node rd_node;         /* Link with superblock */
        struct gfs2_glock *rd_gl;       /* Glock for this rgrp */
        u64 rd_addr;                    /* grp block disk address */
        u64 rd_data0;                   /* first data location */
        u32 rd_length;                  /* length of rgrp header in fs blocks */
        u32 rd_data;                    /* num of data blocks in rgrp */
        u32 rd_bitbytes;                /* number of bytes in data bitmaps */
        u32 rd_free;
        u32 rd_free_clone;
        u32 rd_dinodes;
        u64 rd_igeneration;
        struct gfs2_bitmap *rd_bits;
        struct gfs2_sbd *rd_sbd;
        u32 rd_last_alloc;
        u32 rd_flags;
#define GFS2_RDF_CHECK          0x10000000 /* check for unlinked inodes */
#define GFS2_RDF_UPTODATE       0x20000000 /* rg is up to date */
#define GFS2_RDF_ERROR          0x40000000 /* error in rg */
#define GFS2_RDF_MASK           0xf0000000 /* mask for internal flags */
};

enum gfs2_state_bits {
        BH_Pinned = BH_PrivateStart,
        BH_Escaped = BH_PrivateStart + 1,
        BH_Zeronew = BH_PrivateStart + 2,
};

BUFFER_FNS(Pinned, pinned)
TAS_BUFFER_FNS(Pinned, pinned)
BUFFER_FNS(Escaped, escaped)
TAS_BUFFER_FNS(Escaped, escaped)
BUFFER_FNS(Zeronew, zeronew)
TAS_BUFFER_FNS(Zeronew, zeronew)

struct gfs2_bufdata {
        struct buffer_head *bd_bh;
        struct gfs2_glock *bd_gl;
        u64 bd_blkno;

        struct list_head bd_list;
        const struct gfs2_log_operations *bd_ops;

        struct gfs2_ail *bd_ail;
        struct list_head bd_ail_st_list;
        struct list_head bd_ail_gl_list;
};

/*
 * Internally, we prefix things with gdlm_ and GDLM_ (for gfs-dlm) since a
 * prefix of lock_dlm_ gets awkward.
 */

#define GDLM_STRNAME_BYTES      25
#define GDLM_LVB_SIZE           32

/*
 * ls_recover_flags:
 *
 * DFL_BLOCK_LOCKS: dlm is in recovery and will grant locks that had been
 * held by failed nodes whose journals need recovery.  Those locks should
 * only be used for journal recovery until the journal recovery is done.
 * This is set by the dlm recover_prep callback and cleared by the
 * gfs2_control thread when journal recovery is complete.  To avoid
 * races between recover_prep setting and gfs2_control clearing, recover_spin
 * is held while changing this bit and reading/writing recover_block
 * and recover_start.
 *
 * DFL_NO_DLM_OPS: dlm lockspace ops/callbacks are not being used.
 *
 * DFL_FIRST_MOUNT: this node is the first to mount this fs and is doing
 * recovery of all journals before allowing other nodes to mount the fs.
 * This is cleared when FIRST_MOUNT_DONE is set.
 *
 * DFL_FIRST_MOUNT_DONE: this node was the first mounter, and has finished
 * recovery of all journals, and now allows other nodes to mount the fs.
 *
 * DFL_MOUNT_DONE: gdlm_mount has completed successfully and cleared
 * BLOCK_LOCKS for the first time.  The gfs2_control thread should now
 * control clearing BLOCK_LOCKS for further recoveries.
 *
 * DFL_UNMOUNT: gdlm_unmount sets to keep sdp off gfs2_control_wq.
 *
 * DFL_DLM_RECOVERY: set while dlm is in recovery, between recover_prep()
 * and recover_done(), i.e. set while recover_block == recover_start.
 */

enum {
        DFL_BLOCK_LOCKS         = 0,
        DFL_NO_DLM_OPS          = 1,
        DFL_FIRST_MOUNT         = 2,
        DFL_FIRST_MOUNT_DONE    = 3,
        DFL_MOUNT_DONE          = 4,
        DFL_UNMOUNT             = 5,
        DFL_DLM_RECOVERY        = 6,
};

struct lm_lockname {
        u64 ln_number;
        unsigned int ln_type;
};

#define lm_name_equal(name1, name2) \
        (((name1)->ln_number == (name2)->ln_number) && \
         ((name1)->ln_type == (name2)->ln_type))


struct gfs2_glock_operations {
        void (*go_xmote_th) (struct gfs2_glock *gl);
        int (*go_xmote_bh) (struct gfs2_glock *gl, struct gfs2_holder *gh);
        void (*go_inval) (struct gfs2_glock *gl, int flags);
        int (*go_demote_ok) (const struct gfs2_glock *gl);
        int (*go_lock) (struct gfs2_holder *gh);
        void (*go_unlock) (struct gfs2_holder *gh);
        int (*go_dump)(struct seq_file *seq, const struct gfs2_glock *gl);
        void (*go_callback) (struct gfs2_glock *gl);
        const int go_type;
        const unsigned long go_flags;
#define GLOF_ASPACE 1
};

enum {
        GFS2_LKS_SRTT = 0,      /* Non blocking smoothed round trip time */
        GFS2_LKS_SRTTVAR = 1,   /* Non blocking smoothed variance */
        GFS2_LKS_SRTTB = 2,     /* Blocking smoothed round trip time */
        GFS2_LKS_SRTTVARB = 3,  /* Blocking smoothed variance */
        GFS2_LKS_SIRT = 4,      /* Smoothed Inter-request time */
        GFS2_LKS_SIRTVAR = 5,   /* Smoothed Inter-request variance */
        GFS2_LKS_DCOUNT = 6,    /* Count of dlm requests */
        GFS2_LKS_QCOUNT = 7,    /* Count of gfs2_holder queues */
        GFS2_NR_LKSTATS
};

struct gfs2_lkstats {
        s64 stats[GFS2_NR_LKSTATS];
};

enum {
        /* States */
        HIF_HOLDER              = 6,  /* Set for gh that "holds" the glock */
        HIF_FIRST               = 7,
        HIF_WAIT                = 10,
};

struct gfs2_holder {
        struct list_head gh_list;

        struct gfs2_glock *gh_gl;
        struct pid *gh_owner_pid;
        unsigned int gh_state;
        unsigned gh_flags;

        int gh_error;
        unsigned long gh_iflags; /* HIF_... */
        unsigned long gh_ip;
};

enum {
        GLF_LOCK                        = 1,
        GLF_DEMOTE                      = 3,
        GLF_PENDING_DEMOTE              = 4,
        GLF_DEMOTE_IN_PROGRESS          = 5,
        GLF_DIRTY                       = 6,
        GLF_LFLUSH                      = 7,
        GLF_INVALIDATE_IN_PROGRESS      = 8,
        GLF_REPLY_PENDING               = 9,
        GLF_INITIAL                     = 10,
        GLF_FROZEN                      = 11,
        GLF_QUEUED                      = 12,
        GLF_LRU                         = 13,
        GLF_OBJECT                      = 14, /* Used only for tracing */
        GLF_BLOCKING                    = 15,
};

struct gfs2_glock {
        struct hlist_bl_node gl_list;
        struct gfs2_sbd *gl_sbd;
        unsigned long gl_flags;         /* GLF_... */
        struct lm_lockname gl_name;
        atomic_t gl_ref;

        spinlock_t gl_spin;

        /* State fields protected by gl_spin */
        unsigned int gl_state:2,        /* Current state */
                     gl_target:2,       /* Target state */
                     gl_demote_state:2, /* State requested by remote node */
                     gl_req:2,          /* State in last dlm request */
                     gl_reply:8;        /* Last reply from the dlm */

        unsigned int gl_hash;
        unsigned long gl_demote_time; /* time of first demote request */
        long gl_hold_time;
        struct list_head gl_holders;

        const struct gfs2_glock_operations *gl_ops;
        ktime_t gl_dstamp;
        struct gfs2_lkstats gl_stats;
        struct dlm_lksb gl_lksb;
        char gl_lvb[32];
        unsigned long gl_tchange;
        void *gl_object;

        struct list_head gl_lru;
        struct list_head gl_ail_list;
        atomic_t gl_ail_count;
        atomic_t gl_revokes;
        struct delayed_work gl_work;
        struct work_struct gl_delete;
        struct rcu_head gl_rcu;
};

#define GFS2_MIN_LVB_SIZE 32    /* Min size of LVB that gfs2 supports */

struct gfs2_blkreserv {
        u32 rs_requested; /* Filled in by caller of gfs2_inplace_reserve() */
        struct gfs2_holder rs_rgd_gh; /* Filled in by gfs2_inplace_reserve() */

        /* ancillary quota stuff */
        struct gfs2_quota_data *rs_qa_qd[2 * MAXQUOTAS];
        struct gfs2_holder rs_qa_qd_ghs[2 * MAXQUOTAS];
        unsigned int rs_qa_qd_num;
};

enum {
        GIF_INVALID             = 0,
        GIF_QD_LOCKED           = 1,
        GIF_ALLOC_FAILED        = 2,
        GIF_SW_PAGED            = 3,
};


struct gfs2_inode {
        struct inode i_inode;
        u64 i_no_addr;
        u64 i_no_formal_ino;
        u64 i_generation;
        u64 i_eattr;
        unsigned long i_flags;          /* GIF_... */
        struct gfs2_glock *i_gl; /* Move into i_gh? */
        struct gfs2_holder i_iopen_gh;
        struct gfs2_holder i_gh; /* for prepare/commit_write only */
        struct gfs2_blkreserv *i_res; /* resource group block reservation */
        struct gfs2_rgrpd *i_rgd;
        u64 i_goal;     /* goal block for allocations */
        struct rw_semaphore i_rw_mutex;
        struct list_head i_trunc_list;
        __be64 *i_hash_cache;
        u32 i_entries;
        u32 i_diskflags;
        u8 i_height;
        u8 i_depth;
};

/*
 * Since i_inode is the first element of struct gfs2_inode,
 * this is effectively a cast.
 */
static inline struct gfs2_inode *GFS2_I(struct inode *inode)
{
        return container_of(inode, struct gfs2_inode, i_inode);
}

static inline struct gfs2_sbd *GFS2_SB(const struct inode *inode)
{
        return inode->i_sb->s_fs_info;
}

struct gfs2_file {
        struct mutex f_fl_mutex;
        struct gfs2_holder f_fl_gh;
};

struct gfs2_revoke_replay {
        struct list_head rr_list;
        u64 rr_blkno;
        unsigned int rr_where;
};

enum {
        QDF_USER                = 0,
        QDF_CHANGE              = 1,
        QDF_LOCKED              = 2,
        QDF_REFRESH             = 3,
};

struct gfs2_quota_data {
        struct list_head qd_list;
        struct list_head qd_reclaim;

        atomic_t qd_count;

        u32 qd_id;
        unsigned long qd_flags;         /* QDF_... */

        s64 qd_change;
        s64 qd_change_sync;

        unsigned int qd_slot;
        unsigned int qd_slot_count;

        struct buffer_head *qd_bh;
        struct gfs2_quota_change *qd_bh_qc;
        unsigned int qd_bh_count;

        struct gfs2_glock *qd_gl;
        struct gfs2_quota_lvb qd_qb;

        u64 qd_sync_gen;
        unsigned long qd_last_warn;
};

struct gfs2_trans {
        unsigned long tr_ip;

        unsigned int tr_blocks;
        unsigned int tr_revokes;
        unsigned int tr_reserved;

        struct gfs2_holder tr_t_gh;

        int tr_touched;

        unsigned int tr_num_buf_new;
        unsigned int tr_num_databuf_new;
        unsigned int tr_num_buf_rm;
        unsigned int tr_num_databuf_rm;
        unsigned int tr_num_revoke;
        unsigned int tr_num_revoke_rm;
};

struct gfs2_ail {
        struct list_head ai_list;

        unsigned int ai_first;
        struct list_head ai_ail1_list;
        struct list_head ai_ail2_list;
};

struct gfs2_journal_extent {
        struct list_head extent_list;

        unsigned int lblock; /* First logical block */
        u64 dblock; /* First disk block */
        u64 blocks;
};

struct gfs2_jdesc {
        struct list_head jd_list;
        struct list_head extent_list;
        struct work_struct jd_work;
        struct inode *jd_inode;
        unsigned long jd_flags;
#define JDF_RECOVERY 1
        unsigned int jd_jid;
        unsigned int jd_blocks;
        int jd_recover_error;
};

struct gfs2_statfs_change_host {
        s64 sc_total;
        s64 sc_free;
        s64 sc_dinodes;
};

#define GFS2_QUOTA_DEFAULT      GFS2_QUOTA_OFF
#define GFS2_QUOTA_OFF          0
#define GFS2_QUOTA_ACCOUNT      1
#define GFS2_QUOTA_ON           2

#define GFS2_DATA_DEFAULT       GFS2_DATA_ORDERED
#define GFS2_DATA_WRITEBACK     1
#define GFS2_DATA_ORDERED       2

#define GFS2_ERRORS_DEFAULT     GFS2_ERRORS_WITHDRAW
#define GFS2_ERRORS_WITHDRAW    0
#define GFS2_ERRORS_CONTINUE    1 /* place holder for future feature */
#define GFS2_ERRORS_RO          2 /* place holder for future feature */
#define GFS2_ERRORS_PANIC       3

struct gfs2_args {
        char ar_lockproto[GFS2_LOCKNAME_LEN];   /* Name of the Lock Protocol */
        char ar_locktable[GFS2_LOCKNAME_LEN];   /* Name of the Lock Table */
        char ar_hostdata[GFS2_LOCKNAME_LEN];    /* Host specific data */
        unsigned int ar_spectator:1;            /* Don't get a journal */
        unsigned int ar_localflocks:1;          /* Let the VFS do flock|fcntl */
        unsigned int ar_debug:1;                /* Oops on errors */
        unsigned int ar_posix_acl:1;            /* Enable posix acls */
        unsigned int ar_quota:2;                /* off/account/on */
        unsigned int ar_suiddir:1;              /* suiddir support */
        unsigned int ar_data:2;                 /* ordered/writeback */
        unsigned int ar_meta:1;                 /* mount metafs */
        unsigned int ar_discard:1;              /* discard requests */
        unsigned int ar_errors:2;               /* errors=withdraw | panic */
        unsigned int ar_nobarrier:1;            /* do not send barriers */
        int ar_commit;                          /* Commit interval */
        int ar_statfs_quantum;                  /* The fast statfs interval */
        int ar_quota_quantum;                   /* The quota interval */
        int ar_statfs_percent;                  /* The % change to force sync */
};

struct gfs2_tune {
        spinlock_t gt_spin;

        unsigned int gt_logd_secs;

        unsigned int gt_quota_simul_sync; /* Max quotavals to sync at once */
        unsigned int gt_quota_warn_period; /* Secs between quota warn msgs */
        unsigned int gt_quota_scale_num; /* Numerator */
        unsigned int gt_quota_scale_den; /* Denominator */
        unsigned int gt_quota_quantum; /* Secs between syncs to quota file */
        unsigned int gt_new_files_jdata;
        unsigned int gt_max_readahead; /* Max bytes to read-ahead from disk */
        unsigned int gt_complain_secs;
        unsigned int gt_statfs_quantum;
        unsigned int gt_statfs_slow;
};

enum {
        SDF_JOURNAL_CHECKED     = 0,
        SDF_JOURNAL_LIVE        = 1,
        SDF_SHUTDOWN            = 2,
        SDF_NOBARRIERS          = 3,
        SDF_NORECOVERY          = 4,
        SDF_DEMOTE              = 5,
        SDF_NOJOURNALID         = 6,
        SDF_RORECOVERY          = 7, /* read only recovery */
};

#define GFS2_FSNAME_LEN         256

struct gfs2_inum_host {
        u64 no_formal_ino;
        u64 no_addr;
};

struct gfs2_sb_host {
        u32 sb_magic;
        u32 sb_type;
        u32 sb_format;

        u32 sb_fs_format;
        u32 sb_multihost_format;
        u32 sb_bsize;
        u32 sb_bsize_shift;

        struct gfs2_inum_host sb_master_dir;
        struct gfs2_inum_host sb_root_dir;

        char sb_lockproto[GFS2_LOCKNAME_LEN];
        char sb_locktable[GFS2_LOCKNAME_LEN];
};

/*
 * lm_mount() return values
 *
 * ls_jid - the journal ID this node should use
 * ls_first - this node is the first to mount the file system
 * ls_lockspace - lock module's context for this file system
 * ls_ops - lock module's functions
 */

struct lm_lockstruct {
        int ls_jid;
        unsigned int ls_first;
        const struct lm_lockops *ls_ops;
        dlm_lockspace_t *ls_dlm;

        int ls_recover_jid_done;   /* These two are deprecated, */
        int ls_recover_jid_status; /* used previously by gfs_controld */

        struct dlm_lksb ls_mounted_lksb; /* mounted_lock */
        struct dlm_lksb ls_control_lksb; /* control_lock */
        char ls_control_lvb[GDLM_LVB_SIZE]; /* control_lock lvb */
        struct completion ls_sync_wait; /* {control,mounted}_{lock,unlock} */

        spinlock_t ls_recover_spin; /* protects following fields */
        unsigned long ls_recover_flags; /* DFL_ */
        uint32_t ls_recover_mount; /* gen in first recover_done cb */
        uint32_t ls_recover_start; /* gen in last recover_done cb */
        uint32_t ls_recover_block; /* copy recover_start in last recover_prep */
        uint32_t ls_recover_size; /* size of recover_submit, recover_result */
        uint32_t *ls_recover_submit; /* gen in last recover_slot cb per jid */
        uint32_t *ls_recover_result; /* result of last jid recovery */
};

struct gfs2_pcpu_lkstats {
        /* One struct for each glock type */
        struct gfs2_lkstats lkstats[10];
};

struct gfs2_sbd {
        struct super_block *sd_vfs;
        struct gfs2_pcpu_lkstats __percpu *sd_lkstats;
        struct kobject sd_kobj;
        unsigned long sd_flags; /* SDF_... */
        struct gfs2_sb_host sd_sb;

        /* Constants computed on mount */

        u32 sd_fsb2bb;
        u32 sd_fsb2bb_shift;
        u32 sd_diptrs;  /* Number of pointers in a dinode */
        u32 sd_inptrs;  /* Number of pointers in a indirect block */
        u32 sd_jbsize;  /* Size of a journaled data block */
        u32 sd_hash_bsize;      /* sizeof(exhash block) */
        u32 sd_hash_bsize_shift;
        u32 sd_hash_ptrs;       /* Number of pointers in a hash block */
        u32 sd_qc_per_block;
        u32 sd_max_dirres;      /* Max blocks needed to add a directory entry */
        u32 sd_max_height;      /* Max height of a file's metadata tree */
        u64 sd_heightsize[GFS2_MAX_META_HEIGHT + 1];
        u32 sd_max_jheight; /* Max height of journaled file's meta tree */
        u64 sd_jheightsize[GFS2_MAX_META_HEIGHT + 1];

        struct gfs2_args sd_args;       /* Mount arguments */
        struct gfs2_tune sd_tune;       /* Filesystem tuning structure */

        /* Lock Stuff */

        struct lm_lockstruct sd_lockstruct;
        struct gfs2_holder sd_live_gh;
        struct gfs2_glock *sd_rename_gl;
        struct gfs2_glock *sd_trans_gl;
        wait_queue_head_t sd_glock_wait;
        atomic_t sd_glock_disposal;
        struct completion sd_locking_init;
        struct delayed_work sd_control_work;

        /* Inode Stuff */

        struct dentry *sd_master_dir;
        struct dentry *sd_root_dir;

        struct inode *sd_jindex;
        struct inode *sd_statfs_inode;
        struct inode *sd_sc_inode;
        struct inode *sd_qc_inode;
        struct inode *sd_rindex;
        struct inode *sd_quota_inode;

        /* StatFS stuff */

        spinlock_t sd_statfs_spin;
        struct gfs2_statfs_change_host sd_statfs_master;
        struct gfs2_statfs_change_host sd_statfs_local;
        int sd_statfs_force_sync;

        /* Resource group stuff */

        int sd_rindex_uptodate;
        spinlock_t sd_rindex_spin;
        struct rb_root sd_rindex_tree;
        unsigned int sd_rgrps;
        unsigned int sd_max_rg_data;

        /* Journal index stuff */

        struct list_head sd_jindex_list;
        spinlock_t sd_jindex_spin;
        struct mutex sd_jindex_mutex;
        unsigned int sd_journals;

        struct gfs2_jdesc *sd_jdesc;
        struct gfs2_holder sd_journal_gh;
        struct gfs2_holder sd_jinode_gh;

        struct gfs2_holder sd_sc_gh;
        struct gfs2_holder sd_qc_gh;

        /* Daemon stuff */

        struct task_struct *sd_logd_process;
        struct task_struct *sd_quotad_process;

        /* Quota stuff */

        struct list_head sd_quota_list;
        atomic_t sd_quota_count;
        struct mutex sd_quota_mutex;
        wait_queue_head_t sd_quota_wait;
        struct list_head sd_trunc_list;
        spinlock_t sd_trunc_lock;

        unsigned int sd_quota_slots;
        unsigned int sd_quota_chunks;
        unsigned char **sd_quota_bitmap;

        u64 sd_quota_sync_gen;

        /* Log stuff */

        spinlock_t sd_log_lock;

        unsigned int sd_log_blks_reserved;
        unsigned int sd_log_commited_buf;
        unsigned int sd_log_commited_databuf;
        int sd_log_commited_revoke;

        atomic_t sd_log_pinned;
        unsigned int sd_log_num_buf;
        unsigned int sd_log_num_revoke;
        unsigned int sd_log_num_rg;
        unsigned int sd_log_num_databuf;

        struct list_head sd_log_le_buf;
        struct list_head sd_log_le_revoke;
        struct list_head sd_log_le_databuf;
        struct list_head sd_log_le_ordered;

        atomic_t sd_log_thresh1;
        atomic_t sd_log_thresh2;
        atomic_t sd_log_blks_free;
        wait_queue_head_t sd_log_waitq;
        wait_queue_head_t sd_logd_waitq;

        u64 sd_log_sequence;
        unsigned int sd_log_head;
        unsigned int sd_log_tail;
        int sd_log_idle;

        struct rw_semaphore sd_log_flush_lock;
        atomic_t sd_log_in_flight;
        struct bio *sd_log_bio;
        wait_queue_head_t sd_log_flush_wait;
        int sd_log_error;

        unsigned int sd_log_flush_head;
        u64 sd_log_flush_wrapped;

        spinlock_t sd_ail_lock;
        struct list_head sd_ail1_list;
        struct list_head sd_ail2_list;

        /* Replay stuff */

        struct list_head sd_revoke_list;
        unsigned int sd_replay_tail;

        unsigned int sd_found_blocks;
        unsigned int sd_found_revokes;
        unsigned int sd_replayed_blocks;

        /* For quiescing the filesystem */

        struct gfs2_holder sd_freeze_gh;
        struct mutex sd_freeze_lock;
        unsigned int sd_freeze_count;

        char sd_fsname[GFS2_FSNAME_LEN];
        char sd_table_name[GFS2_FSNAME_LEN];
        char sd_proto_name[GFS2_FSNAME_LEN];

        /* Debugging crud */

        unsigned long sd_last_warning;
        struct dentry *debugfs_dir;    /* debugfs directory */
        struct dentry *debugfs_dentry_glocks;
        struct dentry *debugfs_dentry_glstats;
        struct dentry *debugfs_dentry_sbstats;
};

static inline void gfs2_glstats_inc(struct gfs2_glock *gl, int which)
{
        gl->gl_stats.stats[which]++;
}

static inline void gfs2_sbstats_inc(const struct gfs2_glock *gl, int which)
{
        const struct gfs2_sbd *sdp = gl->gl_sbd;
        preempt_disable();
        this_cpu_ptr(sdp->sd_lkstats)->lkstats[gl->gl_name.ln_type].stats[which]++;
        preempt_enable();
}

#endif /* __INCORE_DOT_H__ */