LXR linux/fs/dlm/dlm

   1/******************************************************************************
   2*******************************************************************************
   3**
   4**  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
   5**  Copyright (C) 2004-2010 Red Hat, Inc.  All rights reserved.
   6**
   7**  This copyrighted material is made available to anyone wishing to use,
   8**  modify, copy, or redistribute it subject to the terms and conditions
   9**  of the GNU General Public License v.2.
  10**
  11*******************************************************************************
  12******************************************************************************/
  13
  14#ifndef __DLM_INTERNAL_DOT_H__
  15#define __DLM_INTERNAL_DOT_H__
  16
  17/*
  18 * This is the main header file to be included in each DLM source file.
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/slab.h>
  23#include <linux/sched.h>
  24#include <linux/types.h>
  25#include <linux/ctype.h>
  26#include <linux/spinlock.h>
  27#include <linux/vmalloc.h>
  28#include <linux/list.h>
  29#include <linux/errno.h>
  30#include <linux/random.h>
  31#include <linux/delay.h>
  32#include <linux/socket.h>
  33#include <linux/kthread.h>
  34#include <linux/kobject.h>
  35#include <linux/kref.h>
  36#include <linux/kernel.h>
  37#include <linux/jhash.h>
  38#include <linux/miscdevice.h>
  39#include <linux/mutex.h>
  40#include <linux/idr.h>
  41#include <asm/uaccess.h>
  42
  43#include <linux/dlm.h>
  44#include "config.h"
  45
  46/* Size of the temp buffer midcomms allocates on the stack.
  47   We try to make this large enough so most messages fit.
  48   FIXME: should sctp make this unnecessary? */
  49
  50#define DLM_INBUF_LEN           148
  51
  52struct dlm_ls;
  53struct dlm_lkb;
  54struct dlm_rsb;
  55struct dlm_member;
  56struct dlm_rsbtable;
  57struct dlm_dirtable;
  58struct dlm_direntry;
  59struct dlm_recover;
  60struct dlm_header;
  61struct dlm_message;
  62struct dlm_rcom;
  63struct dlm_mhandle;
  64
  65#define log_print(fmt, args...) \
  66        printk(KERN_ERR "dlm: "fmt"\n" , ##args)
  67#define log_error(ls, fmt, args...) \
  68        printk(KERN_ERR "dlm: %s: " fmt "\n", (ls)->ls_name , ##args)
  69
  70#define log_debug(ls, fmt, args...) \
  71do { \
  72        if (dlm_config.ci_log_debug) \
  73                printk(KERN_DEBUG "dlm: %s: " fmt "\n", \
  74                       (ls)->ls_name , ##args); \
  75} while (0)
  76
  77#define DLM_ASSERT(x, do) \
  78{ \
  79  if (!(x)) \
  80  { \
  81    printk(KERN_ERR "\nDLM:  Assertion failed on line %d of file %s\n" \
  82               "DLM:  assertion:  \"%s\"\n" \
  83               "DLM:  time = %lu\n", \
  84               __LINE__, __FILE__, #x, jiffies); \
  85    {do} \
  86    printk("\n"); \
  87    BUG(); \
  88    panic("DLM:  Record message above and reboot.\n"); \
  89  } \
  90}
  91
  92
  93struct dlm_direntry {
  94        struct list_head        list;
  95        uint32_t                master_nodeid;
  96        uint16_t                length;
  97        char                    name[1];
  98};
  99
 100struct dlm_dirtable {
 101        struct list_head        list;
 102        spinlock_t              lock;
 103};
 104
 105struct dlm_rsbtable {
 106        struct list_head        list;
 107        struct list_head        toss;
 108        spinlock_t              lock;
 109};
 110
 111
 112/*
 113 * Lockspace member (per node in a ls)
 114 */
 115
 116struct dlm_member {
 117        struct list_head        list;
 118        int                     nodeid;
 119        int                     weight;
 120};
 121
 122/*
 123 * Save and manage recovery state for a lockspace.
 124 */
 125
 126struct dlm_recover {
 127        struct list_head        list;
 128        int                     *nodeids;   /* nodeids of all members */
 129        int                     node_count;
 130        int                     *new;       /* nodeids of new members */
 131        int                     new_count;
 132        uint64_t                seq;
 133};
 134
 135/*
 136 * Pass input args to second stage locking function.
 137 */
 138
 139struct dlm_args {
 140        uint32_t                flags;
 141        void                    (*astfn) (void *astparam);
 142        void                    *astparam;
 143        void                    (*bastfn) (void *astparam, int mode);
 144        int                     mode;
 145        struct dlm_lksb         *lksb;
 146        unsigned long           timeout;
 147};
 148
 149
 150/*
 151 * Lock block
 152 *
 153 * A lock can be one of three types:
 154 *
 155 * local copy      lock is mastered locally
 156 *                 (lkb_nodeid is zero and DLM_LKF_MSTCPY is not set)
 157 * process copy    lock is mastered on a remote node
 158 *                 (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is not set)
 159 * master copy     master node's copy of a lock owned by remote node
 160 *                 (lkb_nodeid is non-zero and DLM_LKF_MSTCPY is set)
 161 *
 162 * lkb_exflags: a copy of the most recent flags arg provided to dlm_lock or
 163 * dlm_unlock.  The dlm does not modify these or use any private flags in
 164 * this field; it only contains DLM_LKF_ flags from dlm.h.  These flags
 165 * are sent as-is to the remote master when the lock is remote.
 166 *
 167 * lkb_flags: internal dlm flags (DLM_IFL_ prefix) from dlm_internal.h.
 168 * Some internal flags are shared between the master and process nodes;
 169 * these shared flags are kept in the lower two bytes.  One of these
 170 * flags set on the master copy will be propagated to the process copy
 171 * and v.v.  Other internal flags are private to the master or process
 172 * node (e.g. DLM_IFL_MSTCPY).  These are kept in the high two bytes.
 173 *
 174 * lkb_sbflags: status block flags.  These flags are copied directly into
 175 * the caller's lksb.sb_flags prior to the dlm_lock/dlm_unlock completion
 176 * ast.  All defined in dlm.h with DLM_SBF_ prefix.
 177 *
 178 * lkb_status: the lock status indicates which rsb queue the lock is
 179 * on, grant, convert, or wait.  DLM_LKSTS_ WAITING/GRANTED/CONVERT
 180 *
 181 * lkb_wait_type: the dlm message type (DLM_MSG_ prefix) for which a
 182 * reply is needed.  Only set when the lkb is on the lockspace waiters
 183 * list awaiting a reply from a remote node.
 184 *
 185 * lkb_nodeid: when the lkb is a local copy, nodeid is 0; when the lkb
 186 * is a master copy, nodeid specifies the remote lock holder, when the
 187 * lkb is a process copy, the nodeid specifies the lock master.
 188 */
 189
 190/* lkb_status */
 191
 192#define DLM_LKSTS_WAITING       1
 193#define DLM_LKSTS_GRANTED       2
 194#define DLM_LKSTS_CONVERT       3
 195
 196/* lkb_flags */
 197
 198#define DLM_IFL_MSTCPY          0x00010000
 199#define DLM_IFL_RESEND          0x00020000
 200#define DLM_IFL_DEAD            0x00040000
 201#define DLM_IFL_OVERLAP_UNLOCK  0x00080000
 202#define DLM_IFL_OVERLAP_CANCEL  0x00100000
 203#define DLM_IFL_ENDOFLIFE       0x00200000
 204#define DLM_IFL_WATCH_TIMEWARN  0x00400000
 205#define DLM_IFL_TIMEOUT_CANCEL  0x00800000
 206#define DLM_IFL_DEADLOCK_CANCEL 0x01000000
 207#define DLM_IFL_STUB_MS         0x02000000 /* magic number for m_flags */
 208#define DLM_IFL_USER            0x00000001
 209#define DLM_IFL_ORPHAN          0x00000002
 210
 211#define DLM_CALLBACKS_SIZE      6
 212
 213#define DLM_CB_CAST             0x00000001
 214#define DLM_CB_BAST             0x00000002
 215#define DLM_CB_SKIP             0x00000004
 216
 217struct dlm_callback {
 218        uint64_t                seq;
 219        uint32_t                flags;          /* DLM_CBF_ */
 220        int                     sb_status;      /* copy to lksb status */
 221        uint8_t                 sb_flags;       /* copy to lksb flags */
 222        int8_t                  mode; /* rq mode of bast, gr mode of cast */
 223};
 224
 225struct dlm_lkb {
 226        struct dlm_rsb          *lkb_resource;  /* the rsb */
 227        struct kref             lkb_ref;
 228        int                     lkb_nodeid;     /* copied from rsb */
 229        int                     lkb_ownpid;     /* pid of lock owner */
 230        uint32_t                lkb_id;         /* our lock ID */
 231        uint32_t                lkb_remid;      /* lock ID on remote partner */
 232        uint32_t                lkb_exflags;    /* external flags from caller */
 233        uint32_t                lkb_sbflags;    /* lksb flags */
 234        uint32_t                lkb_flags;      /* internal flags */
 235        uint32_t                lkb_lvbseq;     /* lvb sequence number */
 236
 237        int8_t                  lkb_status;     /* granted, waiting, convert */
 238        int8_t                  lkb_rqmode;     /* requested lock mode */
 239        int8_t                  lkb_grmode;     /* granted lock mode */
 240        int8_t                  lkb_highbast;   /* highest mode bast sent for */
 241
 242        int8_t                  lkb_wait_type;  /* type of reply waiting for */
 243        int8_t                  lkb_wait_count;
 244        int                     lkb_wait_nodeid; /* for debugging */
 245
 246        struct list_head        lkb_statequeue; /* rsb g/c/w list */
 247        struct list_head        lkb_rsb_lookup; /* waiting for rsb lookup */
 248        struct list_head        lkb_wait_reply; /* waiting for remote reply */
 249        struct list_head        lkb_ownqueue;   /* list of locks for a process */
 250        struct list_head        lkb_time_list;
 251        ktime_t                 lkb_timestamp;
 252        ktime_t                 lkb_wait_time;
 253        unsigned long           lkb_timeout_cs;
 254
 255        struct mutex            lkb_cb_mutex;
 256        struct work_struct      lkb_cb_work;
 257        struct list_head        lkb_cb_list; /* for ls_cb_delay or proc->asts */
 258        struct dlm_callback     lkb_callbacks[DLM_CALLBACKS_SIZE];
 259        struct dlm_callback     lkb_last_cast;
 260        struct dlm_callback     lkb_last_bast;
 261        ktime_t                 lkb_last_cast_time;     /* for debugging */
 262        ktime_t                 lkb_last_bast_time;     /* for debugging */
 263
 264        char                    *lkb_lvbptr;
 265        struct dlm_lksb         *lkb_lksb;      /* caller's status block */
 266        void                    (*lkb_astfn) (void *astparam);
 267        void                    (*lkb_bastfn) (void *astparam, int mode);
 268        union {
 269                void                    *lkb_astparam;  /* caller's ast arg */
 270                struct dlm_user_args    *lkb_ua;
 271        };
 272};
 273
 274
 275struct dlm_rsb {
 276        struct dlm_ls           *res_ls;        /* the lockspace */
 277        struct kref             res_ref;
 278        struct mutex            res_mutex;
 279        unsigned long           res_flags;
 280        int                     res_length;     /* length of rsb name */
 281        int                     res_nodeid;
 282        uint32_t                res_lvbseq;
 283        uint32_t                res_hash;
 284        uint32_t                res_bucket;     /* rsbtbl */
 285        unsigned long           res_toss_time;
 286        uint32_t                res_first_lkid;
 287        struct list_head        res_lookup;     /* lkbs waiting on first */
 288        struct list_head        res_hashchain;  /* rsbtbl */
 289        struct list_head        res_grantqueue;
 290        struct list_head        res_convertqueue;
 291        struct list_head        res_waitqueue;
 292
 293        struct list_head        res_root_list;      /* used for recovery */
 294        struct list_head        res_recover_list;   /* used for recovery */
 295        int                     res_recover_locks_count;
 296
 297        char                    *res_lvbptr;
 298        char                    res_name[DLM_RESNAME_MAXLEN+1];
 299};
 300
 301/* find_rsb() flags */
 302
 303#define R_MASTER                1       /* only return rsb if it's a master */
 304#define R_CREATE                2       /* create/add rsb if not found */
 305
 306/* rsb_flags */
 307
 308enum rsb_flags {
 309        RSB_MASTER_UNCERTAIN,
 310        RSB_VALNOTVALID,
 311        RSB_VALNOTVALID_PREV,
 312        RSB_NEW_MASTER,
 313        RSB_NEW_MASTER2,
 314        RSB_RECOVER_CONVERT,
 315        RSB_LOCKS_PURGED,
 316};
 317
 318static inline void rsb_set_flag(struct dlm_rsb *r, enum rsb_flags flag)
 319{
 320        __set_bit(flag, &r->res_flags);
 321}
 322
 323static inline void rsb_clear_flag(struct dlm_rsb *r, enum rsb_flags flag)
 324{
 325        __clear_bit(flag, &r->res_flags);
 326}
 327
 328static inline int rsb_flag(struct dlm_rsb *r, enum rsb_flags flag)
 329{
 330        return test_bit(flag, &r->res_flags);
 331}
 332
 333
 334/* dlm_header is first element of all structs sent between nodes */
 335
 336#define DLM_HEADER_MAJOR        0x00030000
 337#define DLM_HEADER_MINOR        0x00000000
 338
 339#define DLM_MSG                 1
 340#define DLM_RCOM                2
 341
 342struct dlm_header {
 343        uint32_t                h_version;
 344        uint32_t                h_lockspace;
 345        uint32_t                h_nodeid;       /* nodeid of sender */
 346        uint16_t                h_length;
 347        uint8_t                 h_cmd;          /* DLM_MSG, DLM_RCOM */
 348        uint8_t                 h_pad;
 349};
 350
 351
 352#define DLM_MSG_REQUEST         1
 353#define DLM_MSG_CONVERT         2
 354#define DLM_MSG_UNLOCK          3
 355#define DLM_MSG_CANCEL          4
 356#define DLM_MSG_REQUEST_REPLY   5
 357#define DLM_MSG_CONVERT_REPLY   6
 358#define DLM_MSG_UNLOCK_REPLY    7
 359#define DLM_MSG_CANCEL_REPLY    8
 360#define DLM_MSG_GRANT           9
 361#define DLM_MSG_BAST            10
 362#define DLM_MSG_LOOKUP          11
 363#define DLM_MSG_REMOVE          12
 364#define DLM_MSG_LOOKUP_REPLY    13
 365#define DLM_MSG_PURGE           14
 366
 367struct dlm_message {
 368        struct dlm_header       m_header;
 369        uint32_t                m_type;         /* DLM_MSG_ */
 370        uint32_t                m_nodeid;
 371        uint32_t                m_pid;
 372        uint32_t                m_lkid;         /* lkid on sender */
 373        uint32_t                m_remid;        /* lkid on receiver */
 374        uint32_t                m_parent_lkid;
 375        uint32_t                m_parent_remid;
 376        uint32_t                m_exflags;
 377        uint32_t                m_sbflags;
 378        uint32_t                m_flags;
 379        uint32_t                m_lvbseq;
 380        uint32_t                m_hash;
 381        int                     m_status;
 382        int                     m_grmode;
 383        int                     m_rqmode;
 384        int                     m_bastmode;
 385        int                     m_asts;
 386        int                     m_result;       /* 0 or -EXXX */
 387        char                    m_extra[0];     /* name or lvb */
 388};
 389
 390
 391#define DLM_RS_NODES            0x00000001
 392#define DLM_RS_NODES_ALL        0x00000002
 393#define DLM_RS_DIR              0x00000004
 394#define DLM_RS_DIR_ALL          0x00000008
 395#define DLM_RS_LOCKS            0x00000010
 396#define DLM_RS_LOCKS_ALL        0x00000020
 397#define DLM_RS_DONE             0x00000040
 398#define DLM_RS_DONE_ALL         0x00000080
 399
 400#define DLM_RCOM_STATUS         1
 401#define DLM_RCOM_NAMES          2
 402#define DLM_RCOM_LOOKUP         3
 403#define DLM_RCOM_LOCK           4
 404#define DLM_RCOM_STATUS_REPLY   5
 405#define DLM_RCOM_NAMES_REPLY    6
 406#define DLM_RCOM_LOOKUP_REPLY   7
 407#define DLM_RCOM_LOCK_REPLY     8
 408
 409struct dlm_rcom {
 410        struct dlm_header       rc_header;
 411        uint32_t                rc_type;        /* DLM_RCOM_ */
 412        int                     rc_result;      /* multi-purpose */
 413        uint64_t                rc_id;          /* match reply with request */
 414        uint64_t                rc_seq;         /* sender's ls_recover_seq */
 415        uint64_t                rc_seq_reply;   /* remote ls_recover_seq */
 416        char                    rc_buf[0];
 417};
 418
 419union dlm_packet {
 420        struct dlm_header       header;         /* common to other two */
 421        struct dlm_message      message;
 422        struct dlm_rcom         rcom;
 423};
 424
 425struct rcom_config {
 426        __le32                  rf_lvblen;
 427        __le32                  rf_lsflags;
 428        __le64                  rf_unused;
 429};
 430
 431struct rcom_lock {
 432        __le32                  rl_ownpid;
 433        __le32                  rl_lkid;
 434        __le32                  rl_remid;
 435        __le32                  rl_parent_lkid;
 436        __le32                  rl_parent_remid;
 437        __le32                  rl_exflags;
 438        __le32                  rl_flags;
 439        __le32                  rl_lvbseq;
 440        __le32                  rl_result;
 441        int8_t                  rl_rqmode;
 442        int8_t                  rl_grmode;
 443        int8_t                  rl_status;
 444        int8_t                  rl_asts;
 445        __le16                  rl_wait_type;
 446        __le16                  rl_namelen;
 447        char                    rl_name[DLM_RESNAME_MAXLEN];
 448        char                    rl_lvb[0];
 449};
 450
 451struct dlm_ls {
 452        struct list_head        ls_list;        /* list of lockspaces */
 453        dlm_lockspace_t         *ls_local_handle;
 454        uint32_t                ls_global_id;   /* global unique lockspace ID */
 455        uint32_t                ls_exflags;
 456        int                     ls_lvblen;
 457        int                     ls_count;       /* refcount of processes in
 458                                                   the dlm using this ls */
 459        int                     ls_create_count; /* create/release refcount */
 460        unsigned long           ls_flags;       /* LSFL_ */
 461        unsigned long           ls_scan_time;
 462        struct kobject          ls_kobj;
 463
 464        struct idr              ls_lkbidr;
 465        spinlock_t              ls_lkbidr_spin;
 466
 467        struct dlm_rsbtable     *ls_rsbtbl;
 468        uint32_t                ls_rsbtbl_size;
 469
 470        struct dlm_dirtable     *ls_dirtbl;
 471        uint32_t                ls_dirtbl_size;
 472
 473        struct mutex            ls_waiters_mutex;
 474        struct list_head        ls_waiters;     /* lkbs needing a reply */
 475
 476        struct mutex            ls_orphans_mutex;
 477        struct list_head        ls_orphans;
 478
 479        struct mutex            ls_timeout_mutex;
 480        struct list_head        ls_timeout;
 481
 482        spinlock_t              ls_new_rsb_spin;
 483        int                     ls_new_rsb_count;
 484        struct list_head        ls_new_rsb;     /* new rsb structs */
 485
 486        struct list_head        ls_nodes;       /* current nodes in ls */
 487        struct list_head        ls_nodes_gone;  /* dead node list, recovery */
 488        int                     ls_num_nodes;   /* number of nodes in ls */
 489        int                     ls_low_nodeid;
 490        int                     ls_total_weight;
 491        int                     *ls_node_array;
 492
 493        struct dlm_rsb          ls_stub_rsb;    /* for returning errors */
 494        struct dlm_lkb          ls_stub_lkb;    /* for returning errors */
 495        struct dlm_message      ls_stub_ms;     /* for faking a reply */
 496
 497        struct dentry           *ls_debug_rsb_dentry; /* debugfs */
 498        struct dentry           *ls_debug_waiters_dentry; /* debugfs */
 499        struct dentry           *ls_debug_locks_dentry; /* debugfs */
 500        struct dentry           *ls_debug_all_dentry; /* debugfs */
 501
 502        wait_queue_head_t       ls_uevent_wait; /* user part of join/leave */
 503        int                     ls_uevent_result;
 504        struct completion       ls_members_done;
 505        int                     ls_members_result;
 506
 507        struct miscdevice       ls_device;
 508
 509        struct workqueue_struct *ls_callback_wq;
 510
 511        /* recovery related */
 512
 513        struct mutex            ls_cb_mutex;
 514        struct list_head        ls_cb_delay; /* save for queue_work later */
 515        struct timer_list       ls_timer;
 516        struct task_struct      *ls_recoverd_task;
 517        struct mutex            ls_recoverd_active;
 518        spinlock_t              ls_recover_lock;
 519        unsigned long           ls_recover_begin; /* jiffies timestamp */
 520        uint32_t                ls_recover_status; /* DLM_RS_ */
 521        uint64_t                ls_recover_seq;
 522        struct dlm_recover      *ls_recover_args;
 523        struct rw_semaphore     ls_in_recovery; /* block local requests */
 524        struct rw_semaphore     ls_recv_active; /* block dlm_recv */
 525        struct list_head        ls_requestqueue;/* queue remote requests */
 526        struct mutex            ls_requestqueue_mutex;
 527        struct dlm_rcom         *ls_recover_buf;
 528        int                     ls_recover_nodeid; /* for debugging */
 529        uint64_t                ls_rcom_seq;
 530        spinlock_t              ls_rcom_spin;
 531        struct list_head        ls_recover_list;
 532        spinlock_t              ls_recover_list_lock;
 533        int                     ls_recover_list_count;
 534        wait_queue_head_t       ls_wait_general;
 535        struct mutex            ls_clear_proc_locks;
 536
 537        struct list_head        ls_root_list;   /* root resources */
 538        struct rw_semaphore     ls_root_sem;    /* protect root_list */
 539
 540        int                     ls_namelen;
 541        char                    ls_name[1];
 542};
 543
 544#define LSFL_WORK               0
 545#define LSFL_RUNNING            1
 546#define LSFL_RECOVERY_STOP      2
 547#define LSFL_RCOM_READY         3
 548#define LSFL_RCOM_WAIT          4
 549#define LSFL_UEVENT_WAIT        5
 550#define LSFL_TIMEWARN           6
 551#define LSFL_CB_DELAY           7
 552
 553/* much of this is just saving user space pointers associated with the
 554   lock that we pass back to the user lib with an ast */
 555
 556struct dlm_user_args {
 557        struct dlm_user_proc    *proc; /* each process that opens the lockspace
 558                                          device has private data
 559                                          (dlm_user_proc) on the struct file,
 560                                          the process's locks point back to it*/
 561        struct dlm_lksb         lksb;
 562        struct dlm_lksb __user  *user_lksb;
 563        void __user             *castparam;
 564        void __user             *castaddr;
 565        void __user             *bastparam;
 566        void __user             *bastaddr;
 567        uint64_t                xid;
 568};
 569
 570#define DLM_PROC_FLAGS_CLOSING 1
 571#define DLM_PROC_FLAGS_COMPAT  2
 572
 573/* locks list is kept so we can remove all a process's locks when it
 574   exits (or orphan those that are persistent) */
 575
 576struct dlm_user_proc {
 577        dlm_lockspace_t         *lockspace;
 578        unsigned long           flags; /* DLM_PROC_FLAGS */
 579        struct list_head        asts;
 580        spinlock_t              asts_spin;
 581        struct list_head        locks;
 582        spinlock_t              locks_spin;
 583        struct list_head        unlocking;
 584        wait_queue_head_t       wait;
 585};
 586
 587static inline int dlm_locking_stopped(struct dlm_ls *ls)
 588{
 589        return !test_bit(LSFL_RUNNING, &ls->ls_flags);
 590}
 591
 592static inline int dlm_recovery_stopped(struct dlm_ls *ls)
 593{
 594        return test_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
 595}
 596
 597static inline int dlm_no_directory(struct dlm_ls *ls)
 598{
 599        return (ls->ls_exflags & DLM_LSFL_NODIR) ? 1 : 0;
 600}
 601
 602int dlm_netlink_init(void);
 603void dlm_netlink_exit(void);
 604void dlm_timeout_warn(struct dlm_lkb *lkb);
 605int dlm_plock_init(void);
 606void dlm_plock_exit(void);
 607
 608#ifdef CONFIG_DLM_DEBUG
 609int dlm_register_debugfs(void);
 610void dlm_unregister_debugfs(void);
 611int dlm_create_debug_file(struct dlm_ls *ls);
 612void dlm_delete_debug_file(struct dlm_ls *ls);
 613#else
 614static inline int dlm_register_debugfs(void) { return 0; }
 615static inline void dlm_unregister_debugfs(void) { }
 616static inline int dlm_create_debug_file(struct dlm_ls *ls) { return 0; }
 617static inline void dlm_delete_debug_file(struct dlm_ls *ls) { }
 618#endif
 619
 620#endif                          /* __DLM_INTERNAL_DOT_H__ */
 621
 622