fs/nfs/nfs4_fs.h

   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
  26 struct idmap;
  27
  28 enum 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
  47 struct 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
  67 struct 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
  77 struct nfs_seqid {
  78         struct nfs_seqid_counter *sequence;
  79         struct list_head list;
  80         struct rpc_task *task;
  81 };
  82
  83 static 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  */
  94 struct 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
 111 enum {
 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
 132 struct 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 */
 145 enum {
 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
 158 struct 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
 182 struct nfs4_exception {
 183         long timeout;
 184         int retry;
 185         struct nfs4_state *state;
 186         struct inode *inode;
 187 };
 188
 189 struct 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
 200 struct 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
 206 struct 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
 212 extern const struct dentry_operations nfs4_dentry_operations;
 213
 214 /* dir.c */
 215 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 216                     unsigned, umode_t, int *);
 217
 218 /* super.c */
 219 extern struct file_system_type nfs4_fs_type;
 220
 221 /* nfs4namespace.c */
 222 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *, struct qstr *);
 223 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 224                                struct nfs_fh *, struct nfs_fattr *);
 225 int nfs4_replace_transport(struct nfs_server *server,
 226                                 const struct nfs4_fs_locations *locations);
 227
 228 /* nfs4proc.c */
 229 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 230 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
 231                           struct rpc_message *, struct nfs4_sequence_args *,
 232                           struct nfs4_sequence_res *, int);
 233 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
 234 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
 235 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 236 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 237 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 238 extern int nfs4_destroy_clientid(struct nfs_client *clp);
 239 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 240 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 241 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
 242 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 243 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 244                                   struct nfs4_fs_locations *, struct page *);
 245 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
 246                 struct page *page, struct rpc_cred *);
 247 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 248 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
 249                             struct nfs_fh *, struct nfs_fattr *);
 250 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 251 extern const struct xattr_handler *nfs4_xattr_handlers[];
 252 extern 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)
 258 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 259 {
 260         return server->nfs_client->cl_session;
 261 }
 262
 263 extern int nfs41_setup_sequence(struct nfs4_session *session,
 264                 struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
 265                 struct rpc_task *task);
 266 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
 267 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 268 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 269 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 270                 struct nfs_fsinfo *fsinfo);
 271 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 272                                   bool sync);
 273
 274 static inline bool
 275 is_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
 281 static inline bool
 282 is_ds_client(struct nfs_client *clp)
 283 {
 284         return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
 285 }
 286
 287 static 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  */
 319 static inline void
 320 nfs4_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  */
 331 static inline void
 332 nfs4_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 */
 340 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 341 {
 342         return NULL;
 343 }
 344
 345 static inline bool
 346 is_ds_only_client(struct nfs_client *clp)
 347 {
 348         return false;
 349 }
 350
 351 static inline bool
 352 is_ds_client(struct nfs_client *clp)
 353 {
 354         return false;
 355 }
 356
 357 static inline void
 358 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 359                    struct rpc_clnt **clntp, struct rpc_message *msg)
 360 {
 361 }
 362
 363 static inline void
 364 nfs4_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
 370 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
 371
 372 extern const u32 nfs4_fattr_bitmap[3];
 373 extern const u32 nfs4_statfs_bitmap[3];
 374 extern const u32 nfs4_pathconf_bitmap[3];
 375 extern const u32 nfs4_fsinfo_bitmap[3];
 376 extern const u32 nfs4_fs_locations_bitmap[3];
 377
 378 void nfs40_shutdown_client(struct nfs_client *);
 379 void nfs41_shutdown_client(struct nfs_client *);
 380 int nfs40_init_client(struct nfs_client *);
 381 int nfs41_init_client(struct nfs_client *);
 382 void nfs4_free_client(struct nfs_client *);
 383
 384 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
 385
 386 /* nfs4renewd.c */
 387 extern void nfs4_schedule_state_renewal(struct nfs_client *);
 388 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
 389 extern void nfs4_kill_renewd(struct nfs_client *);
 390 extern void nfs4_renew_state(struct work_struct *);
 391
 392 /* nfs4state.c */
 393 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
 394 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 395 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 396 int nfs4_discover_server_trunking(struct nfs_client *clp,
 397                         struct nfs_client **);
 398 int nfs40_discover_server_trunking(struct nfs_client *clp,
 399                         struct nfs_client **, struct rpc_cred *);
 400 #if defined(CONFIG_NFS_V4_1)
 401 int nfs41_discover_server_trunking(struct nfs_client *clp,
 402                         struct nfs_client **, struct rpc_cred *);
 403 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 404 extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
 405 extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);
 406
 407 #else
 408 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 409 {
 410 }
 411 #endif /* CONFIG_NFS_V4_1 */
 412
 413 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 414 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
 415 extern void nfs4_purge_state_owners(struct nfs_server *);
 416 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
 417 extern void nfs4_put_open_state(struct nfs4_state *);
 418 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
 419 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
 420 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
 421 extern void nfs_inode_find_state_and_recover(struct inode *inode,
 422                 const nfs4_stateid *stateid);
 423 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
 424 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 425 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 426 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 427 extern void nfs4_schedule_state_manager(struct nfs_client *);
 428 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 429 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 430 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 431 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 432 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
 433 extern void nfs41_handle_server_scope(struct nfs_client *,
 434                                       struct nfs41_server_scope **);
 435 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
 436 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
 437 extern int nfs4_select_rw_stateid(nfs4_stateid *, struct nfs4_state *,
 438                 fmode_t, const struct nfs_lockowner *);
 439
 440 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
 441 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
 442 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
 443 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
 444 extern void nfs_release_seqid(struct nfs_seqid *seqid);
 445 extern void nfs_free_seqid(struct nfs_seqid *seqid);
 446
 447 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
 448
 449 extern const nfs4_stateid zero_stateid;
 450
 451 /* nfs4super.c */
 452 struct nfs_mount_info;
 453 extern struct nfs_subversion nfs_v4;
 454 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 455 extern bool nfs4_disable_idmapping;
 456 extern unsigned short max_session_slots;
 457 extern unsigned short send_implementation_id;
 458 extern bool recover_lost_locks;
 459
 460 #define NFS4_CLIENT_ID_UNIQ_LEN         (64)
 461 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 462
 463 /* nfs4sysctl.c */
 464 #ifdef CONFIG_SYSCTL
 465 int nfs4_register_sysctl(void);
 466 void nfs4_unregister_sysctl(void);
 467 #else
 468 static inline int nfs4_register_sysctl(void)
 469 {
 470         return 0;
 471 }
 472
 473 static inline void nfs4_unregister_sysctl(void)
 474 {
 475 }
 476 #endif
 477
 478 /* nfs4xdr.c */
 479 extern struct rpc_procinfo nfs4_procedures[];
 480
 481 struct nfs4_mount_data;
 482
 483 /* callback_xdr.c */
 484 extern struct svc_version nfs4_callback_version1;
 485 extern struct svc_version nfs4_callback_version4;
 486
 487 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 488 {
 489         memcpy(dst, src, sizeof(*dst));
 490 }
 491
 492 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 493 {
 494         return memcmp(dst, src, sizeof(*dst)) == 0;
 495 }
 496
 497 static 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
 502 static 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
 507 static 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 */