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         atomic_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 };
 166
 167 struct nfs4_state {
 168         struct list_head open_states;   /* List of states for the same state_owner */
 169         struct list_head inode_states;  /* List of states for the same inode */
 170         struct list_head lock_states;   /* List of subservient lock stateids */
 171
 172         struct nfs4_state_owner *owner; /* Pointer to the open owner */
 173         struct inode *inode;            /* Pointer to the inode */
 174
 175         unsigned long flags;            /* Do we hold any locks? */
 176         spinlock_t state_lock;          /* Protects the lock_states list */
 177
 178         seqlock_t seqlock;              /* Protects the stateid/open_stateid */
 179         nfs4_stateid stateid;           /* Current stateid: may be delegation */
 180         nfs4_stateid open_stateid;      /* OPEN stateid */
 181
 182         /* The following 3 fields are protected by owner->so_lock */
 183         unsigned int n_rdonly;          /* Number of read-only references */
 184         unsigned int n_wronly;          /* Number of write-only references */
 185         unsigned int n_rdwr;            /* Number of read/write references */
 186         fmode_t state;                  /* State on the server (R,W, or RW) */
 187         atomic_t count;
 188 };
 189
 190
 191 struct nfs4_exception {
 192         struct nfs4_state *state;
 193         struct inode *inode;
 194         nfs4_stateid *stateid;
 195         long timeout;
 196         unsigned char delay : 1,
 197                       recovering : 1,
 198                       retry : 1;
 199 };
 200
 201 struct nfs4_state_recovery_ops {
 202         int owner_flag_bit;
 203         int state_flag_bit;
 204         int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
 205         int (*recover_lock)(struct nfs4_state *, struct file_lock *);
 206         int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
 207         int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
 208         int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
 209                 struct rpc_cred *);
 210 };
 211
 212 struct nfs4_add_xprt_data {
 213         struct nfs_client       *clp;
 214         struct rpc_cred         *cred;
 215 };
 216
 217 struct nfs4_state_maintenance_ops {
 218         int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
 219         struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
 220         int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
 221 };
 222
 223 struct nfs4_mig_recovery_ops {
 224         int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
 225                 struct page *, struct rpc_cred *);
 226         int (*fsid_present)(struct inode *, struct rpc_cred *);
 227 };
 228
 229 extern const struct dentry_operations nfs4_dentry_operations;
 230
 231 /* dir.c */
 232 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 233                     unsigned, umode_t, int *);
 234
 235 /* super.c */
 236 extern struct file_system_type nfs4_fs_type;
 237
 238 /* nfs4namespace.c */
 239 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
 240                                          const struct qstr *);
 241 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 242                                struct nfs_fh *, struct nfs_fattr *);
 243 int nfs4_replace_transport(struct nfs_server *server,
 244                                 const struct nfs4_fs_locations *locations);
 245
 246 /* nfs4proc.c */
 247 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
 248 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
 249                           struct rpc_message *, struct nfs4_sequence_args *,
 250                           struct nfs4_sequence_res *, int);
 251 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int);
 252 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
 253 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
 254 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 255 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 256 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 257 extern int nfs4_destroy_clientid(struct nfs_client *clp);
 258 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
 259 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
 260 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
 261 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 262 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 263                                   struct nfs4_fs_locations *, struct page *);
 264 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
 265                 struct page *page, struct rpc_cred *);
 266 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 267 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, const struct qstr *,
 268                             struct nfs_fh *, struct nfs_fattr *);
 269 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 270 extern const struct xattr_handler *nfs4_xattr_handlers[];
 271 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
 272                 const struct nfs_open_context *ctx,
 273                 const struct nfs_lock_context *l_ctx,
 274                 fmode_t fmode);
 275
 276 #if defined(CONFIG_NFS_V4_1)
 277 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
 278 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 279 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 280 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 281                 struct nfs_fsinfo *fsinfo);
 282 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 283                                   bool sync);
 284 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
 285                 struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
 286
 287 static inline bool
 288 is_ds_only_client(struct nfs_client *clp)
 289 {
 290         return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
 291                 EXCHGID4_FLAG_USE_PNFS_DS;
 292 }
 293
 294 static inline bool
 295 is_ds_client(struct nfs_client *clp)
 296 {
 297         return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
 298 }
 299
 300 static inline bool
 301 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 302                     struct rpc_clnt **clntp, struct rpc_message *msg)
 303 {
 304         struct rpc_cred *newcred = NULL;
 305         rpc_authflavor_t flavor;
 306
 307         if (sp4_mode == NFS_SP4_MACH_CRED_CLEANUP ||
 308             sp4_mode == NFS_SP4_MACH_CRED_PNFS_CLEANUP) {
 309                 /* Using machine creds for cleanup operations
 310                  * is only relevent if the client credentials
 311                  * might expire. So don't bother for
 312                  * RPC_AUTH_UNIX.  If file was only exported to
 313                  * sec=sys, the PUTFH would fail anyway.
 314                  */
 315                 if ((*clntp)->cl_auth->au_flavor == RPC_AUTH_UNIX)
 316                         return false;
 317         }
 318         if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
 319                 spin_lock(&clp->cl_lock);
 320                 if (clp->cl_machine_cred != NULL)
 321                         /* don't call get_rpccred on the machine cred -
 322                          * a reference will be held for life of clp */
 323                         newcred = clp->cl_machine_cred;
 324                 spin_unlock(&clp->cl_lock);
 325                 msg->rpc_cred = newcred;
 326
 327                 flavor = clp->cl_rpcclient->cl_auth->au_flavor;
 328                 WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
 329                              flavor != RPC_AUTH_GSS_KRB5P);
 330                 *clntp = clp->cl_rpcclient;
 331
 332                 return true;
 333         }
 334         return false;
 335 }
 336
 337 /*
 338  * Function responsible for determining if an rpc_message should use the
 339  * machine cred under SP4_MACH_CRED and if so switching the credential and
 340  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
 341  * Should be called before rpc_call_sync/rpc_call_async.
 342  */
 343 static inline void
 344 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 345                    struct rpc_clnt **clntp, struct rpc_message *msg)
 346 {
 347         _nfs4_state_protect(clp, sp4_mode, clntp, msg);
 348 }
 349
 350 /*
 351  * Special wrapper to nfs4_state_protect for write.
 352  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
 353  * that use machine cred use NFS_FILE_SYNC.
 354  */
 355 static inline void
 356 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 357                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 358 {
 359         if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
 360             !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
 361                 hdr->args.stable = NFS_FILE_SYNC;
 362 }
 363 #else /* CONFIG_NFS_v4_1 */
 364 static inline bool
 365 is_ds_only_client(struct nfs_client *clp)
 366 {
 367         return false;
 368 }
 369
 370 static inline bool
 371 is_ds_client(struct nfs_client *clp)
 372 {
 373         return false;
 374 }
 375
 376 static inline void
 377 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 378                    struct rpc_clnt **clntp, struct rpc_message *msg)
 379 {
 380 }
 381
 382 static inline void
 383 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 384                          struct rpc_message *msg, struct nfs_pgio_header *hdr)
 385 {
 386 }
 387 #endif /* CONFIG_NFS_V4_1 */
 388
 389 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
 390
 391 extern const u32 nfs4_fattr_bitmap[3];
 392 extern const u32 nfs4_statfs_bitmap[3];
 393 extern const u32 nfs4_pathconf_bitmap[3];
 394 extern const u32 nfs4_fsinfo_bitmap[3];
 395 extern const u32 nfs4_fs_locations_bitmap[3];
 396
 397 void nfs40_shutdown_client(struct nfs_client *);
 398 void nfs41_shutdown_client(struct nfs_client *);
 399 int nfs40_init_client(struct nfs_client *);
 400 int nfs41_init_client(struct nfs_client *);
 401 void nfs4_free_client(struct nfs_client *);
 402
 403 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
 404
 405 /* nfs4renewd.c */
 406 extern void nfs4_schedule_state_renewal(struct nfs_client *);
 407 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
 408 extern void nfs4_kill_renewd(struct nfs_client *);
 409 extern void nfs4_renew_state(struct work_struct *);
 410 extern void nfs4_set_lease_period(struct nfs_client *clp,
 411                 unsigned long lease,
 412                 unsigned long lastrenewed);
 413
 414
 415 /* nfs4state.c */
 416 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
 417 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 418 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 419 int nfs4_discover_server_trunking(struct nfs_client *clp,
 420                         struct nfs_client **);
 421 int nfs40_discover_server_trunking(struct nfs_client *clp,
 422                         struct nfs_client **, struct rpc_cred *);
 423 #if defined(CONFIG_NFS_V4_1)
 424 int nfs41_discover_server_trunking(struct nfs_client *clp,
 425                         struct nfs_client **, struct rpc_cred *);
 426 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 427 extern void nfs41_notify_server(struct nfs_client *);
 428 #else
 429 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 430 {
 431 }
 432 #endif /* CONFIG_NFS_V4_1 */
 433
 434 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 435 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
 436 extern void nfs4_purge_state_owners(struct nfs_server *, struct list_head *);
 437 extern void nfs4_free_state_owners(struct list_head *head);
 438 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
 439 extern void nfs4_put_open_state(struct nfs4_state *);
 440 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
 441 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
 442 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
 443 extern void nfs_inode_find_state_and_recover(struct inode *inode,
 444                 const nfs4_stateid *stateid);
 445 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
 446 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 447 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 448 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 449 extern void nfs4_schedule_state_manager(struct nfs_client *);
 450 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 451 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 452 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 453 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 454 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
 455 extern void nfs41_handle_server_scope(struct nfs_client *,
 456                                       struct nfs41_server_scope **);
 457 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
 458 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
 459 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
 460                 const struct nfs_lock_context *, nfs4_stateid *,
 461                 struct rpc_cred **);
 462
 463 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
 464 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
 465 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
 466 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
 467 extern void nfs_release_seqid(struct nfs_seqid *seqid);
 468 extern void nfs_free_seqid(struct nfs_seqid *seqid);
 469 extern int nfs4_setup_sequence(struct nfs_client *client,
 470                                 struct nfs4_sequence_args *args,
 471                                 struct nfs4_sequence_res *res,
 472                                 struct rpc_task *task);
 473 extern int nfs4_sequence_done(struct rpc_task *task,
 474                               struct nfs4_sequence_res *res);
 475
 476 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
 477
 478 extern const nfs4_stateid zero_stateid;
 479
 480 /* nfs4super.c */
 481 struct nfs_mount_info;
 482 extern struct nfs_subversion nfs_v4;
 483 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 484 extern bool nfs4_disable_idmapping;
 485 extern unsigned short max_session_slots;
 486 extern unsigned short max_session_cb_slots;
 487 extern unsigned short send_implementation_id;
 488 extern bool recover_lost_locks;
 489
 490 #define NFS4_CLIENT_ID_UNIQ_LEN         (64)
 491 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 492
 493 /* nfs4sysctl.c */
 494 #ifdef CONFIG_SYSCTL
 495 int nfs4_register_sysctl(void);
 496 void nfs4_unregister_sysctl(void);
 497 #else
 498 static inline int nfs4_register_sysctl(void)
 499 {
 500         return 0;
 501 }
 502
 503 static inline void nfs4_unregister_sysctl(void)
 504 {
 505 }
 506 #endif
 507
 508 /* nfs4xdr.c */
 509 extern const struct rpc_procinfo nfs4_procedures[];
 510
 511 struct nfs4_mount_data;
 512
 513 /* callback_xdr.c */
 514 extern const struct svc_version nfs4_callback_version1;
 515 extern const struct svc_version nfs4_callback_version4;
 516
 517 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 518 {
 519         memcpy(dst->data, src->data, sizeof(dst->data));
 520         dst->type = src->type;
 521 }
 522
 523 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 524 {
 525         if (dst->type != src->type)
 526                 return false;
 527         return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
 528 }
 529
 530 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
 531 {
 532         return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
 533 }
 534
 535 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
 536 {
 537         return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
 538 }
 539
 540 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
 541 {
 542         return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
 543 }
 544
 545 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
 546                 const nfs4_stateid *stateid)
 547 {
 548         return test_bit(NFS_OPEN_STATE, &state->flags) &&
 549                 nfs4_stateid_match_other(&state->open_stateid, stateid);
 550 }
 551
 552 #else
 553
 554 #define nfs4_close_state(a, b) do { } while (0)
 555 #define nfs4_close_sync(a, b) do { } while (0)
 556 #define nfs4_state_protect(a, b, c, d) do { } while (0)
 557 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
 558
 559 #endif /* CONFIG_NFS_V4 */
 560 #endif /* __LINUX_FS_NFS_NFS4_FS.H */