LXR linux/fs/nfs/nfs4

   1/*
   2 * linux/fs/nfs/nfs4_fs.h
   3 *
   4 * Copyright (C) 2005 Trond Myklebust
   5 *
   6 * NFSv4-specific filesystem definitions and declarations
   7 */
   8
   9#ifndef __LINUX_FS_NFS_NFS4_FS_H
  10#define __LINUX_FS_NFS_NFS4_FS_H
  11
  12#if defined(CONFIG_NFS_V4_2)
  13#define NFS4_MAX_MINOR_VERSION 2
  14#elif defined(CONFIG_NFS_V4_1)
  15#define NFS4_MAX_MINOR_VERSION 1
  16#else
  17#define NFS4_MAX_MINOR_VERSION 0
  18#endif
  19
  20#if IS_ENABLED(CONFIG_NFS_V4)
  21
  22#define NFS4_MAX_LOOP_ON_RECOVER (10)
  23
  24#include <linux/seqlock.h>
  25
  26struct idmap;
  27
  28enum nfs4_client_state {
  29        NFS4CLNT_MANAGER_RUNNING  = 0,
  30        NFS4CLNT_CHECK_LEASE,
  31        NFS4CLNT_LEASE_EXPIRED,
  32        NFS4CLNT_RECLAIM_REBOOT,
  33        NFS4CLNT_RECLAIM_NOGRACE,
  34        NFS4CLNT_DELEGRETURN,
  35        NFS4CLNT_SESSION_RESET,
  36        NFS4CLNT_LEASE_CONFIRM,
  37        NFS4CLNT_SERVER_SCOPE_MISMATCH,
  38        NFS4CLNT_PURGE_STATE,
  39        NFS4CLNT_BIND_CONN_TO_SESSION,
  40        NFS4CLNT_MOVED,
  41        NFS4CLNT_LEASE_MOVED,
  42};
  43
  44#define NFS4_RENEW_TIMEOUT              0x01
  45#define NFS4_RENEW_DELEGATION_CB        0x02
  46
  47struct nfs4_minor_version_ops {
  48        u32     minor_version;
  49        unsigned init_caps;
  50
  51        int     (*init_client)(struct nfs_client *);
  52        void    (*shutdown_client)(struct nfs_client *);
  53        bool    (*match_stateid)(const nfs4_stateid *,
  54                        const nfs4_stateid *);
  55        int     (*find_root_sec)(struct nfs_server *, struct nfs_fh *,
  56                        struct nfs_fsinfo *);
  57        void    (*free_lock_state)(struct nfs_server *,
  58                        struct nfs4_lock_state *);
  59        const struct rpc_call_ops *call_sync_ops;
  60        const struct nfs4_state_recovery_ops *reboot_recovery_ops;
  61        const struct nfs4_state_recovery_ops *nograce_recovery_ops;
  62        const struct nfs4_state_maintenance_ops *state_renewal_ops;
  63        const struct nfs4_mig_recovery_ops *mig_recovery_ops;
  64};
  65
  66#define NFS_SEQID_CONFIRMED 1
  67struct nfs_seqid_counter {
  68        ktime_t create_time;
  69        int owner_id;
  70        int flags;
  71        u32 counter;
  72        spinlock_t lock;                /* Protects the list */
  73        struct list_head list;          /* Defines sequence of RPC calls */
  74        struct rpc_wait_queue   wait;   /* RPC call delay queue */
  75};
  76
  77struct nfs_seqid {
  78        struct nfs_seqid_counter *sequence;
  79        struct list_head list;
  80        struct rpc_task *task;
  81};
  82
  83static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
  84{
  85        if (seqid_mutating_err(-status))
  86                seqid->flags |= NFS_SEQID_CONFIRMED;
  87}
  88
  89/*
  90 * NFS4 state_owners and lock_owners are simply labels for ordered
  91 * sequences of RPC calls. Their sole purpose is to provide once-only
  92 * semantics by allowing the server to identify replayed requests.
  93 */
  94struct nfs4_state_owner {
  95        struct nfs_server    *so_server;
  96        struct list_head     so_lru;
  97        unsigned long        so_expires;
  98        struct rb_node       so_server_node;
  99
 100        struct rpc_cred      *so_cred;   /* Associated cred */
 101
 102        spinlock_t           so_lock;
 103        atomic_t             so_count;
 104        unsigned long        so_flags;
 105        struct list_head     so_states;
 106        struct nfs_seqid_counter so_seqid;
 107        seqcount_t           so_reclaim_seqcount;
 108        struct mutex         so_delegreturn_mutex;
 109};
 110
 111enum {
 112        NFS_OWNER_RECLAIM_REBOOT,
 113        NFS_OWNER_RECLAIM_NOGRACE
 114};
 115
 116#define NFS_LOCK_NEW            0
 117#define NFS_LOCK_RECLAIM        1
 118#define NFS_LOCK_EXPIRED        2
 119
 120/*
 121 * struct nfs4_state maintains the client-side state for a given
 122 * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
 123 *
 124 * OPEN:
 125 * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
 126 * we need to know how many files are open for reading or writing on a
 127 * given inode. This information too is stored here.
 128 *
 129 * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
 130 */
 131
 132struct nfs4_lock_state {
 133        struct list_head        ls_locks;       /* Other lock stateids */
 134        struct nfs4_state *     ls_state;       /* Pointer to open state */
 135#define NFS_LOCK_INITIALIZED 0
 136#define NFS_LOCK_LOST        1
 137        unsigned long           ls_flags;
 138        struct nfs_seqid_counter        ls_seqid;
 139        nfs4_stateid            ls_stateid;
 140        atomic_t                ls_count;
 141        fl_owner_t              ls_owner;
 142};
 143
 144/* bits for nfs4_state->flags */
 145enum {
 146        LK_STATE_IN_USE,
 147        NFS_DELEGATED_STATE,            /* Current stateid is delegation */
 148        NFS_OPEN_STATE,                 /* OPEN stateid is set */
 149        NFS_O_RDONLY_STATE,             /* OPEN stateid has read-only state */
 150        NFS_O_WRONLY_STATE,             /* OPEN stateid has write-only state */
 151        NFS_O_RDWR_STATE,               /* OPEN stateid has read/write state */
 152        NFS_STATE_RECLAIM_REBOOT,       /* OPEN stateid server rebooted */
 153        NFS_STATE_RECLAIM_NOGRACE,      /* OPEN stateid needs to recover state */
 154        NFS_STATE_POSIX_LOCKS,          /* Posix locks are supported */
 155        NFS_STATE_RECOVERY_FAILED,      /* OPEN stateid state recovery failed */
 156};
 157
 158struct nfs4_state {
 159        struct list_head open_states;   /* List of states for the same state_owner */
 160        struct list_head inode_states;  /* List of states for the same inode */
 161        struct list_head lock_states;   /* List of subservient lock stateids */
 162
 163        struct nfs4_state_owner *owner; /* Pointer to the open owner */
 164        struct inode *inode;            /* Pointer to the inode */
 165
 166        unsigned long flags;            /* Do we hold any locks? */
 167        spinlock_t state_lock;          /* Protects the lock_states list */
 168
 169        seqlock_t seqlock;              /* Protects the stateid/open_stateid */
 170        nfs4_stateid stateid;           /* Current stateid: may be delegation */
 171        nfs4_stateid open_stateid;      /* OPEN stateid */
 172
 173        /* The following 3 fields are protected by owner->so_lock */
 174        unsigned int n_rdonly;          /* Number of read-only references */
 175        unsigned int n_wronly;          /* Number of write-only references */
 176        unsigned int n_rdwr;            /* Number of read/write references */
 177        fmode_t state;                  /* State on the server (R,W, or RW) */
 178        atomic_t count;
 179};
 180
 181
 182struct nfs4_exception {
 183        long timeout;
 184        int retry;
 185        struct nfs4_state *state;
 186        struct inode *inode;
 187};
 188
 189struct nfs4_state_recovery_ops {
 190        int owner_flag_bit;
 191        int state_flag_bit;
 192        int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
 193        int (*recover_lock)(struct nfs4_state *, struct file_lock *);
 194        int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
 195        int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
 196        int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
 197                struct rpc_cred *);
 198};
 199
 200struct nfs4_state_maintenance_ops {
 201        int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
 202        struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
 203        int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
 204};
 205
 206struct nfs4_mig_recovery_ops {
 207        int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
 208                struct page *, struct rpc_cred *);
 209        int (*fsid_present)(struct inode *, struct rpc_cred *);
 210};
 211
 212extern const struct dentry_operations nfs4_dentry_operations;
 213
 214/* dir.c */
 215int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 216                    unsigned, umode_t, int *);
 217
 218/* super.c */
 219extern struct file_system_type nfs4_fs_type;
 220
 221/* nfs4namespace.c */
 222struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *, struct qstr *);
 223struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 224                               struct nfs_fh *, struct nfs_fattr *);
 225int nfs4_replace_transport(struct nfs_server *server,
 226                                const struct nfs4_fs_locations *locations);
 227
 228/* nfs4proc.c */
 229extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 230extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
 231                          struct rpc_message *, struct nfs4_sequence_args *,
 232                          struct nfs4_sequence_res *, int);
 233extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
 234extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
 235extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 236extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 237extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 238extern int nfs4_destroy_clientid(struct nfs_client *clp);
 239extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 240extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 241extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
 242extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 243extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 244                                  struct nfs4_fs_locations *, struct page *);
 245extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
 246                struct page *page, struct rpc_cred *);
 247extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 248extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
 249                            struct nfs_fh *, struct nfs_fattr *);
 250extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 251extern const struct xattr_handler *nfs4_xattr_handlers[];
 252extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
 253                const struct nfs_open_context *ctx,
 254                const struct nfs_lock_context *l_ctx,
 255                fmode_t fmode);
 256
 257#if defined(CONFIG_NFS_V4_1)
 258static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 259{
 260        return server->nfs_client->cl_session;
 261}
 262
 263extern int nfs41_setup_sequence(struct nfs4_session *session,
 264                struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
 265                struct rpc_task *task);
 266extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
 267extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 268extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 269extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 270                struct nfs_fsinfo *fsinfo);
 271extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 272                                  bool sync);
 273
 274static inline bool
 275is_ds_only_client(struct nfs_client *clp)
 276{
 277        return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
 278                EXCHGID4_FLAG_USE_PNFS_DS;
 279}
 280
 281static inline bool
 282is_ds_client(struct nfs_client *clp)
 283{
 284        return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
 285}
 286
 287static inline bool
 288_nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 289                    struct rpc_clnt **clntp, struct rpc_message *msg)
 290{
 291        struct rpc_cred *newcred = NULL;
 292        rpc_authflavor_t flavor;
 293
 294        if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
 295                spin_lock(&clp->cl_lock);
 296                if (clp->cl_machine_cred != NULL)
 297                        /* don't call get_rpccred on the machine cred -
 298                         * a reference will be held for life of clp */
 299                        newcred = clp->cl_machine_cred;
 300                spin_unlock(&clp->cl_lock);
 301                msg->rpc_cred = newcred;
 302
 303                flavor = clp->cl_rpcclient->cl_auth->au_flavor;
 304                WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
 305                             flavor != RPC_AUTH_GSS_KRB5P);
 306                *clntp = clp->cl_rpcclient;
 307
 308                return true;
 309        }
 310        return false;
 311}
 312
 313/*
 314 * Function responsible for determining if an rpc_message should use the
 315 * machine cred under SP4_MACH_CRED and if so switching the credential and
 316 * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
 317 * Should be called before rpc_call_sync/rpc_call_async.
 318 */
 319static inline void
 320nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 321                   struct rpc_clnt **clntp, struct rpc_message *msg)
 322{
 323        _nfs4_state_protect(clp, sp4_mode, clntp, msg);
 324}
 325
 326/*
 327 * Special wrapper to nfs4_state_protect for write.
 328 * If WRITE can use machine cred but COMMIT cannot, make sure all writes
 329 * that use machine cred use NFS_FILE_SYNC.
 330 */
 331static inline void
 332nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 333                         struct rpc_message *msg, struct nfs_pgio_header *hdr)
 334{
 335        if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
 336            !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
 337                hdr->args.stable = NFS_FILE_SYNC;
 338}
 339#else /* CONFIG_NFS_v4_1 */
 340static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 341{
 342        return NULL;
 343}
 344
 345static inline bool
 346is_ds_only_client(struct nfs_client *clp)
 347{
 348        return false;
 349}
 350
 351static inline bool
 352is_ds_client(struct nfs_client *clp)
 353{
 354        return false;
 355}
 356
 357static inline void
 358nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 359                   struct rpc_clnt **clntp, struct rpc_message *msg)
 360{
 361}
 362
 363static inline void
 364nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 365                         struct rpc_message *msg, struct nfs_pgio_header *hdr)
 366{
 367}
 368#endif /* CONFIG_NFS_V4_1 */
 369
 370extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
 371
 372extern const u32 nfs4_fattr_bitmap[3];
 373extern const u32 nfs4_statfs_bitmap[3];
 374extern const u32 nfs4_pathconf_bitmap[3];
 375extern const u32 nfs4_fsinfo_bitmap[3];
 376extern const u32 nfs4_fs_locations_bitmap[3];
 377
 378void nfs40_shutdown_client(struct nfs_client *);
 379void nfs41_shutdown_client(struct nfs_client *);
 380int nfs40_init_client(struct nfs_client *);
 381int nfs41_init_client(struct nfs_client *);
 382void nfs4_free_client(struct nfs_client *);
 383
 384struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
 385
 386/* nfs4renewd.c */
 387extern void nfs4_schedule_state_renewal(struct nfs_client *);
 388extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
 389extern void nfs4_kill_renewd(struct nfs_client *);
 390extern void nfs4_renew_state(struct work_struct *);
 391
 392/* nfs4state.c */
 393struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
 394struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 395struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 396int nfs4_discover_server_trunking(struct nfs_client *clp,
 397                        struct nfs_client **);
 398int nfs40_discover_server_trunking(struct nfs_client *clp,
 399                        struct nfs_client **, struct rpc_cred *);
 400#if defined(CONFIG_NFS_V4_1)
 401int nfs41_discover_server_trunking(struct nfs_client *clp,
 402                        struct nfs_client **, struct rpc_cred *);
 403extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 404extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
 405extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);
 406
 407#else
 408static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 409{
 410}
 411#endif /* CONFIG_NFS_V4_1 */
 412
 413extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 414extern void nfs4_put_state_owner(struct nfs4_state_owner *);
 415extern void nfs4_purge_state_owners(struct nfs_server *);
 416extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
 417extern void nfs4_put_open_state(struct nfs4_state *);
 418extern void nfs4_close_state(struct nfs4_state *, fmode_t);
 419extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
 420extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
 421extern void nfs_inode_find_state_and_recover(struct inode *inode,
 422                const nfs4_stateid *stateid);
 423extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
 424extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 425extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 426extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 427extern void nfs4_schedule_state_manager(struct nfs_client *);
 428extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 429extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 430extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 431extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 432extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
 433extern void nfs41_handle_server_scope(struct nfs_client *,
 434                                      struct nfs41_server_scope **);
 435extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
 436extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
 437extern int nfs4_select_rw_stateid(nfs4_stateid *, struct nfs4_state *,
 438                fmode_t, const struct nfs_lockowner *);
 439
 440extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
 441extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
 442extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
 443extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
 444extern void nfs_release_seqid(struct nfs_seqid *seqid);
 445extern void nfs_free_seqid(struct nfs_seqid *seqid);
 446
 447extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
 448
 449extern const nfs4_stateid zero_stateid;
 450
 451/* nfs4super.c */
 452struct nfs_mount_info;
 453extern struct nfs_subversion nfs_v4;
 454struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 455extern bool nfs4_disable_idmapping;
 456extern unsigned short max_session_slots;
 457extern unsigned short send_implementation_id;
 458extern bool recover_lost_locks;
 459
 460#define NFS4_CLIENT_ID_UNIQ_LEN         (64)
 461extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 462
 463/* nfs4sysctl.c */
 464#ifdef CONFIG_SYSCTL
 465int nfs4_register_sysctl(void);
 466void nfs4_unregister_sysctl(void);
 467#else
 468static inline int nfs4_register_sysctl(void)
 469{
 470        return 0;
 471}
 472
 473static inline void nfs4_unregister_sysctl(void)
 474{
 475}
 476#endif
 477
 478/* nfs4xdr.c */
 479extern struct rpc_procinfo nfs4_procedures[];
 480
 481struct nfs4_mount_data;
 482
 483/* callback_xdr.c */
 484extern struct svc_version nfs4_callback_version1;
 485extern struct svc_version nfs4_callback_version4;
 486
 487static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 488{
 489        memcpy(dst, src, sizeof(*dst));
 490}
 491
 492static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 493{
 494        return memcmp(dst, src, sizeof(*dst)) == 0;
 495}
 496
 497static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
 498{
 499        return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
 500}
 501
 502static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
 503{
 504        return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
 505}
 506
 507static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
 508{
 509        return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
 510}
 511
 512#else
 513
 514#define nfs4_close_state(a, b) do { } while (0)
 515#define nfs4_close_sync(a, b) do { } while (0)
 516#define nfs4_state_protect(a, b, c, d) do { } while (0)
 517#define nfs4_state_protect_write(a, b, c, d) do { } while (0)
 518
 519#endif /* CONFIG_NFS_V4 */
 520#endif /* __LINUX_FS_NFS_NFS4_FS.H */
 521