fs/nfs/nfs4_fs.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * linux/fs/nfs/nfs4_fs.h
   4  *
   5  * Copyright (C) 2005 Trond Myklebust
   6  *
   7  * NFSv4-specific filesystem definitions and declarations
   8  */
   9
  10 #ifndef __LINUX_FS_NFS_NFS4_FS_H
  11 #define __LINUX_FS_NFS_NFS4_FS_H
  12
  13 #if defined(CONFIG_NFS_V4_2)
  14 #define NFS4_MAX_MINOR_VERSION 2
  15 #elif defined(CONFIG_NFS_V4_1)
  16 #define NFS4_MAX_MINOR_VERSION 1
  17 #else
  18 #define NFS4_MAX_MINOR_VERSION 0
  19 #endif
  20
  21 #if IS_ENABLED(CONFIG_NFS_V4)
  22
  23 #define NFS4_MAX_LOOP_ON_RECOVER (10)
  24
  25 #include <linux/seqlock.h>
  26
  27 struct idmap;
  28
  29 enum nfs4_client_state {
  30         NFS4CLNT_MANAGER_RUNNING  = 0,
  31         NFS4CLNT_CHECK_LEASE,
  32         NFS4CLNT_LEASE_EXPIRED,
  33         NFS4CLNT_RECLAIM_REBOOT,
  34         NFS4CLNT_RECLAIM_NOGRACE,
  35         NFS4CLNT_DELEGRETURN,
  36         NFS4CLNT_SESSION_RESET,
  37         NFS4CLNT_LEASE_CONFIRM,
  38         NFS4CLNT_SERVER_SCOPE_MISMATCH,
  39         NFS4CLNT_PURGE_STATE,
  40         NFS4CLNT_BIND_CONN_TO_SESSION,
  41         NFS4CLNT_MOVED,
  42         NFS4CLNT_LEASE_MOVED,
  43         NFS4CLNT_DELEGATION_EXPIRED,
  44 };
  45
  46 #define NFS4_RENEW_TIMEOUT              0x01
  47 #define NFS4_RENEW_DELEGATION_CB        0x02
  48
  49 struct nfs_seqid_counter;
  50 struct nfs4_minor_version_ops {
  51         u32     minor_version;
  52         unsigned init_caps;
  53
  54         int     (*init_client)(struct nfs_client *);
  55         void    (*shutdown_client)(struct nfs_client *);
  56         bool    (*match_stateid)(const nfs4_stateid *,
  57                         const nfs4_stateid *);
  58         int     (*find_root_sec)(struct nfs_server *, struct nfs_fh *,
  59                         struct nfs_fsinfo *);
  60         void    (*free_lock_state)(struct nfs_server *,
  61                         struct nfs4_lock_state *);
  62         int     (*test_and_free_expired)(struct nfs_server *,
  63                         nfs4_stateid *, struct rpc_cred *);
  64         struct nfs_seqid *
  65                 (*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
  66         int     (*session_trunk)(struct rpc_clnt *, struct rpc_xprt *, void *);
  67         const struct rpc_call_ops *call_sync_ops;
  68         const struct nfs4_state_recovery_ops *reboot_recovery_ops;
  69         const struct nfs4_state_recovery_ops *nograce_recovery_ops;
  70         const struct nfs4_state_maintenance_ops *state_renewal_ops;
  71         const struct nfs4_mig_recovery_ops *mig_recovery_ops;
  72 };
  73
  74 #define NFS_SEQID_CONFIRMED 1
  75 struct nfs_seqid_counter {
  76         ktime_t create_time;
  77         int owner_id;
  78         int flags;
  79         u32 counter;
  80         spinlock_t lock;                /* Protects the list */
  81         struct list_head list;          /* Defines sequence of RPC calls */
  82         struct rpc_wait_queue   wait;   /* RPC call delay queue */
  83 };
  84
  85 struct nfs_seqid {
  86         struct nfs_seqid_counter *sequence;
  87         struct list_head list;
  88         struct rpc_task *task;
  89 };
  90
  91 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
  92 {
  93         if (seqid_mutating_err(-status))
  94                 seqid->flags |= NFS_SEQID_CONFIRMED;
  95 }
  96
  97 /*
  98  * NFS4 state_owners and lock_owners are simply labels for ordered
  99  * sequences of RPC calls. Their sole purpose is to provide once-only
 100  * semantics by allowing the server to identify replayed requests.
 101  */
 102 struct nfs4_state_owner {
 103         struct nfs_server    *so_server;
 104         struct list_head     so_lru;
 105         unsigned long        so_expires;
 106         struct rb_node       so_server_node;
 107
 108         struct rpc_cred      *so_cred;   /* Associated cred */
 109
 110         spinlock_t           so_lock;
 111         atomic_t             so_count;
 112         unsigned long        so_flags;
 113         struct list_head     so_states;
 114         struct nfs_seqid_counter so_seqid;
 115         seqcount_t           so_reclaim_seqcount;
 116         struct mutex         so_delegreturn_mutex;
 117 };
 118
 119 enum {
 120         NFS_OWNER_RECLAIM_REBOOT,
 121         NFS_OWNER_RECLAIM_NOGRACE
 122 };
 123
 124 #define NFS_LOCK_NEW            0
 125 #define NFS_LOCK_RECLAIM        1
 126 #define NFS_LOCK_EXPIRED        2
 127
 128 /*
 129  * struct nfs4_state maintains the client-side state for a given
 130  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
 131  *
 132  * OPEN:
 133  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
 134  * we need to know how many files are open for reading or writing on a
 135  * given inode. This information too is stored here.
 136  *
 137  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
 138  */
 139
 140 struct nfs4_lock_state {
 141         struct list_head        ls_locks;       /* Other lock stateids */
 142         struct nfs4_state *     ls_state;       /* Pointer to open state */
 143 #define NFS_LOCK_INITIALIZED 0
 144 #define NFS_LOCK_LOST        1
 145         unsigned long           ls_flags;
 146         struct nfs_seqid_counter        ls_seqid;
 147         nfs4_stateid            ls_stateid;
 148         refcount_t              ls_count;
 149         fl_owner_t              ls_owner;
 150 };
 151
 152 /* bits for nfs4_state->flags */
 153 enum {
 154         LK_STATE_IN_USE,
 155         NFS_DELEGATED_STATE,            /* Current stateid is delegation */
 156         NFS_OPEN_STATE,                 /* OPEN stateid is set */
 157         NFS_O_RDONLY_STATE,             /* OPEN stateid has read-only state */
 158         NFS_O_WRONLY_STATE,             /* OPEN stateid has write-only state */
 159         NFS_O_RDWR_STATE,               /* OPEN stateid has read/write state */
 160         NFS_STATE_RECLAIM_REBOOT,       /* OPEN stateid server rebooted */
 161         NFS_STATE_RECLAIM_NOGRACE,      /* OPEN stateid needs to recover state */
 162         NFS_STATE_POSIX_LOCKS,          /* Posix locks are supported */
 163         NFS_STATE_RECOVERY_FAILED,      /* OPEN stateid state recovery failed */
 164         NFS_STATE_MAY_NOTIFY_LOCK,      /* server may CB_NOTIFY_LOCK */
 165         NFS_STATE_CHANGE_WAIT,          /* A state changing operation is outstanding */
 166 };
 167
 168 struct nfs4_state {
 169         struct list_head open_states;   /* List of states for the same state_owner */
 170         struct list_head inode_states;  /* List of states for the same inode */
 171         struct list_head lock_states;   /* List of subservient lock stateids */
 172
 173         struct nfs4_state_owner *owner; /* Pointer to the open owner */
 174         struct inode *inode;            /* Pointer to the inode */
 175
 176         unsigned long flags;            /* Do we hold any locks? */
 177         spinlock_t state_lock;          /* Protects the lock_states list */
 178
 179         seqlock_t seqlock;              /* Protects the stateid/open_stateid */
 180         nfs4_stateid stateid;           /* Current stateid: may be delegation */
 181         nfs4_stateid open_stateid;      /* OPEN stateid */
 182
 183         /* The following 3 fields are protected by owner->so_lock */
 184         unsigned int n_rdonly;          /* Number of read-only references */
 185         unsigned int n_wronly;          /* Number of write-only references */
 186         unsigned int n_rdwr;            /* Number of read/write references */
 187         fmode_t state;                  /* State on the server (R,W, or RW) */
 188         atomic_t count;
 189
 190         wait_queue_head_t waitq;
 191 };
 192
 193
 194 struct nfs4_exception {
 195         struct nfs4_state *state;
 196         struct inode *inode;
 197         nfs4_stateid *stateid;
 198         long timeout;
 199         unsigned char delay : 1,
 200                       recovering : 1,
 201                       retry : 1;
 202 };
 203
 204 struct nfs4_state_recovery_ops {
 205         int owner_flag_bit;
 206         int state_flag_bit;
 207         int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
 208         int (*recover_lock)(struct nfs4_state *, struct file_lock *);
 209         int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
 210         int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
 211         int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
 212                 struct rpc_cred *);
 213 };
 214
 215 struct nfs4_add_xprt_data {
 216         struct nfs_client       *clp;
 217         struct rpc_cred         *cred;
 218 };
 219
 220 struct nfs4_state_maintenance_ops {
 221         int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
 222         struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
 223         int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
 224 };
 225
 226 struct nfs4_mig_recovery_ops {
 227         int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
 228                 struct page *, struct rpc_cred *);
 229         int (*fsid_present)(struct inode *, struct rpc_cred *);
 230 };
 231
 232 extern const struct dentry_operations nfs4_dentry_operations;
 233
 234 /* dir.c */
 235 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 236                     unsigned, umode_t, int *);
 237
 238 /* super.c */
 239 extern struct file_system_type nfs4_fs_type;
 240
 241 /* nfs4namespace.c */
 242 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
 243                                          const struct qstr *);
 244 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 245                                struct nfs_fh *, struct nfs_fattr *);
 246 int nfs4_replace_transport(struct nfs_server *server,
 247                                 const struct nfs4_fs_locations *locations);
 248
 249 /* nfs4proc.c */
 250 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 251 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
 252                           struct rpc_message *, struct nfs4_sequence_args *,
 253                           struct nfs4_sequence_res *, int);
 254 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int);
 255 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
 256 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
 257 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 258 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 259 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 260 extern int nfs4_destroy_clientid(struct nfs_client *clp);
 261 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 262 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 263 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
 264 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 265 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 266                                   struct nfs4_fs_locations *, struct page *);
 267 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
 268                 struct page *page, struct rpc_cred *);
 269 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 270 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, const struct qstr *,
 271                             struct nfs_fh *, struct nfs_fattr *);
 272 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 273 extern const struct xattr_handler *nfs4_xattr_handlers[];
 274 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
 275                 const struct nfs_open_context *ctx,
 276                 const struct nfs_lock_context *l_ctx,
 277                 fmode_t fmode);
 278
 279 #if defined(CONFIG_NFS_V4_1)
 280 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
 281 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 282 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 283 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 284                 struct nfs_fsinfo *fsinfo);
 285 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 286                                   bool sync);
 287 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
 288                 struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
 289
 290 static inline bool
 291 is_ds_only_client(struct nfs_client *clp)
 292 {
 293         return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
 294                 EXCHGID4_FLAG_USE_PNFS_DS;
 295 }
 296
 297 static inline bool
 298 is_ds_client(struct nfs_client *clp)
 299 {
 300         return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
 301 }
 302
 303 static inline bool
 304 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 305                     struct rpc_clnt **clntp, struct rpc_message *msg)
 306 {
 307         struct rpc_cred *newcred = NULL;
 308         rpc_authflavor_t flavor;
 309
 310         if (sp4_mode == NFS_SP4_MACH_CRED_CLEANUP ||
 311             sp4_mode == NFS_SP4_MACH_CRED_PNFS_CLEANUP) {
 312                 /* Using machine creds for cleanup operations
 313                  * is only relevent if the client credentials
 314                  * might expire. So don't bother for
 315                  * RPC_AUTH_UNIX.  If file was only exported to
 316                  * sec=sys, the PUTFH would fail anyway.
 317                  */
 318                 if ((*clntp)->cl_auth->au_flavor == RPC_AUTH_UNIX)
 319                         return false;
 320         }
 321         if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
 322                 spin_lock(&clp->cl_lock);
 323                 if (clp->cl_machine_cred != NULL)
 324                         /* don't call get_rpccred on the machine cred -
 325                          * a reference will be held for life of clp */
 326                         newcred = clp->cl_machine_cred;
 327                 spin_unlock(&clp->cl_lock);
 328                 msg->rpc_cred = newcred;
 329
 330                 flavor = clp->cl_rpcclient->cl_auth->au_flavor;
 331                 WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
 332                              flavor != RPC_AUTH_GSS_KRB5P);
 333                 *clntp = clp->cl_rpcclient;
 334
 335                 return true;
 336         }
 337         return false;
 338 }
 339
 340 /*
 341  * Function responsible for determining if an rpc_message should use the
 342  * machine cred under SP4_MACH_CRED and if so switching the credential and
 343  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
 344  * Should be called before rpc_call_sync/rpc_call_async.
 345  */
 346 static inline void
 347 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 348                    struct rpc_clnt **clntp, struct rpc_message *msg)
 349 {
 350         _nfs4_state_protect(clp, sp4_mode, clntp, msg);
 351 }
 352
 353 /*
 354  * Special wrapper to nfs4_state_protect for write.
 355  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
 356  * that use machine cred use NFS_FILE_SYNC.
 357  */
 358 static inline void
 359 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 360                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 361 {
 362         if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
 363             !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
 364                 hdr->args.stable = NFS_FILE_SYNC;
 365 }
 366 #else /* CONFIG_NFS_v4_1 */
 367 static inline bool
 368 is_ds_only_client(struct nfs_client *clp)
 369 {
 370         return false;
 371 }
 372
 373 static inline bool
 374 is_ds_client(struct nfs_client *clp)
 375 {
 376         return false;
 377 }
 378
 379 static inline void
 380 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 381                    struct rpc_clnt **clntp, struct rpc_message *msg)
 382 {
 383 }
 384
 385 static inline void
 386 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 387                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 388 {
 389 }
 390 #endif /* CONFIG_NFS_V4_1 */
 391
 392 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
 393
 394 extern const u32 nfs4_fattr_bitmap[3];
 395 extern const u32 nfs4_statfs_bitmap[3];
 396 extern const u32 nfs4_pathconf_bitmap[3];
 397 extern const u32 nfs4_fsinfo_bitmap[3];
 398 extern const u32 nfs4_fs_locations_bitmap[3];
 399
 400 void nfs40_shutdown_client(struct nfs_client *);
 401 void nfs41_shutdown_client(struct nfs_client *);
 402 int nfs40_init_client(struct nfs_client *);
 403 int nfs41_init_client(struct nfs_client *);
 404 void nfs4_free_client(struct nfs_client *);
 405
 406 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
 407
 408 /* nfs4renewd.c */
 409 extern void nfs4_schedule_state_renewal(struct nfs_client *);
 410 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
 411 extern void nfs4_kill_renewd(struct nfs_client *);
 412 extern void nfs4_renew_state(struct work_struct *);
 413 extern void nfs4_set_lease_period(struct nfs_client *clp,
 414                 unsigned long lease,
 415                 unsigned long lastrenewed);
 416
 417
 418 /* nfs4state.c */
 419 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
 420 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 421 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 422 int nfs4_discover_server_trunking(struct nfs_client *clp,
 423                         struct nfs_client **);
 424 int nfs40_discover_server_trunking(struct nfs_client *clp,
 425                         struct nfs_client **, struct rpc_cred *);
 426 #if defined(CONFIG_NFS_V4_1)
 427 int nfs41_discover_server_trunking(struct nfs_client *clp,
 428                         struct nfs_client **, struct rpc_cred *);
 429 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 430 extern void nfs41_notify_server(struct nfs_client *);
 431 #else
 432 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 433 {
 434 }
 435 #endif /* CONFIG_NFS_V4_1 */
 436
 437 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 438 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
 439 extern void nfs4_purge_state_owners(struct nfs_server *);
 440 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
 441 extern void nfs4_put_open_state(struct nfs4_state *);
 442 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
 443 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
 444 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
 445 extern void nfs_inode_find_state_and_recover(struct inode *inode,
 446                 const nfs4_stateid *stateid);
 447 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
 448 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 449 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 450 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 451 extern void nfs4_schedule_state_manager(struct nfs_client *);
 452 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 453 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 454 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 455 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 456 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
 457 extern void nfs41_handle_server_scope(struct nfs_client *,
 458                                       struct nfs41_server_scope **);
 459 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
 460 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
 461 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
 462                 const struct nfs_lock_context *, nfs4_stateid *,
 463                 struct rpc_cred **);
 464 extern bool nfs4_refresh_open_stateid(nfs4_stateid *dst,
 465                 struct nfs4_state *state);
 466 extern bool nfs4_copy_open_stateid(nfs4_stateid *dst,
 467                 struct nfs4_state *state);
 468
 469 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
 470 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
 471 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
 472 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
 473 extern void nfs_release_seqid(struct nfs_seqid *seqid);
 474 extern void nfs_free_seqid(struct nfs_seqid *seqid);
 475 extern int nfs4_setup_sequence(struct nfs_client *client,
 476                                 struct nfs4_sequence_args *args,
 477                                 struct nfs4_sequence_res *res,
 478                                 struct rpc_task *task);
 479 extern int nfs4_sequence_done(struct rpc_task *task,
 480                               struct nfs4_sequence_res *res);
 481
 482 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
 483
 484 extern const nfs4_stateid zero_stateid;
 485 extern const nfs4_stateid invalid_stateid;
 486
 487 /* nfs4super.c */
 488 struct nfs_mount_info;
 489 extern struct nfs_subversion nfs_v4;
 490 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 491 extern bool nfs4_disable_idmapping;
 492 extern unsigned short max_session_slots;
 493 extern unsigned short max_session_cb_slots;
 494 extern unsigned short send_implementation_id;
 495 extern bool recover_lost_locks;
 496
 497 #define NFS4_CLIENT_ID_UNIQ_LEN         (64)
 498 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 499
 500 /* nfs4sysctl.c */
 501 #ifdef CONFIG_SYSCTL
 502 int nfs4_register_sysctl(void);
 503 void nfs4_unregister_sysctl(void);
 504 #else
 505 static inline int nfs4_register_sysctl(void)
 506 {
 507         return 0;
 508 }
 509
 510 static inline void nfs4_unregister_sysctl(void)
 511 {
 512 }
 513 #endif
 514
 515 /* nfs4xdr.c */
 516 extern const struct rpc_procinfo nfs4_procedures[];
 517
 518 struct nfs4_mount_data;
 519
 520 /* callback_xdr.c */
 521 extern const struct svc_version nfs4_callback_version1;
 522 extern const struct svc_version nfs4_callback_version4;
 523
 524 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 525 {
 526         memcpy(dst->data, src->data, sizeof(dst->data));
 527         dst->type = src->type;
 528 }
 529
 530 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 531 {
 532         if (dst->type != src->type)
 533                 return false;
 534         return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
 535 }
 536
 537 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
 538 {
 539         return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
 540 }
 541
 542 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
 543 {
 544         return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
 545 }
 546
 547 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
 548 {
 549         return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
 550 }
 551
 552 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
 553                 const nfs4_stateid *stateid)
 554 {
 555         return test_bit(NFS_OPEN_STATE, &state->flags) &&
 556                 nfs4_stateid_match_other(&state->open_stateid, stateid);
 557 }
 558
 559 #else
 560
 561 #define nfs4_close_state(a, b) do { } while (0)
 562 #define nfs4_close_sync(a, b) do { } while (0)
 563 #define nfs4_state_protect(a, b, c, d) do { } while (0)
 564 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
 565
 566 #endif /* CONFIG_NFS_V4 */
 567 #endif /* __LINUX_FS_NFS_NFS4_FS.H */