LXR linux/include/linux/nfs

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 *  linux/include/linux/nfs_fs.h
   4 *
   5 *  Copyright (C) 1992  Rick Sladkey
   6 *
   7 *  OS-specific nfs filesystem definitions and declarations
   8 */
   9#ifndef _LINUX_NFS_FS_H
  10#define _LINUX_NFS_FS_H
  11
  12#include <uapi/linux/nfs_fs.h>
  13
  14
  15/*
  16 * Enable dprintk() debugging support for nfs client.
  17 */
  18#ifdef CONFIG_NFS_DEBUG
  19# define NFS_DEBUG
  20#endif
  21
  22#include <linux/in.h>
  23#include <linux/mm.h>
  24#include <linux/pagemap.h>
  25#include <linux/rbtree.h>
  26#include <linux/refcount.h>
  27#include <linux/rwsem.h>
  28#include <linux/wait.h>
  29
  30#include <linux/sunrpc/debug.h>
  31#include <linux/sunrpc/auth.h>
  32#include <linux/sunrpc/clnt.h>
  33
  34#include <linux/nfs.h>
  35#include <linux/nfs2.h>
  36#include <linux/nfs3.h>
  37#include <linux/nfs4.h>
  38#include <linux/nfs_xdr.h>
  39#include <linux/nfs_fs_sb.h>
  40
  41#include <linux/mempool.h>
  42
  43/*
  44 * These are the default flags for swap requests
  45 */
  46#define NFS_RPC_SWAPFLAGS               (RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)
  47
  48/*
  49 * NFSv3/v4 Access mode cache entry
  50 */
  51struct nfs_access_entry {
  52        struct rb_node          rb_node;
  53        struct list_head        lru;
  54        const struct cred *     cred;
  55        __u32                   mask;
  56        struct rcu_head         rcu_head;
  57};
  58
  59struct nfs_lock_context {
  60        refcount_t count;
  61        struct list_head list;
  62        struct nfs_open_context *open_context;
  63        fl_owner_t lockowner;
  64        atomic_t io_count;
  65        struct rcu_head rcu_head;
  66};
  67
  68struct nfs4_state;
  69struct nfs_open_context {
  70        struct nfs_lock_context lock_context;
  71        fl_owner_t flock_owner;
  72        struct dentry *dentry;
  73        const struct cred *cred;
  74        struct rpc_cred *ll_cred;       /* low-level cred - use to check for expiry */
  75        struct nfs4_state *state;
  76        fmode_t mode;
  77
  78        unsigned long flags;
  79#define NFS_CONTEXT_RESEND_WRITES       (1)
  80#define NFS_CONTEXT_BAD                 (2)
  81#define NFS_CONTEXT_UNLOCK      (3)
  82        int error;
  83
  84        struct list_head list;
  85        struct nfs4_threshold   *mdsthreshold;
  86        struct rcu_head rcu_head;
  87};
  88
  89struct nfs_open_dir_context {
  90        struct list_head list;
  91        const struct cred *cred;
  92        unsigned long attr_gencount;
  93        __u64 dir_cookie;
  94        __u64 dup_cookie;
  95        signed char duped;
  96};
  97
  98/*
  99 * NFSv4 delegation
 100 */
 101struct nfs_delegation;
 102
 103struct posix_acl;
 104
 105struct nfs4_xattr_cache;
 106
 107/*
 108 * nfs fs inode data in memory
 109 */
 110struct nfs_inode {
 111        /*
 112         * The 64bit 'inode number'
 113         */
 114        __u64 fileid;
 115
 116        /*
 117         * NFS file handle
 118         */
 119        struct nfs_fh           fh;
 120
 121        /*
 122         * Various flags
 123         */
 124        unsigned long           flags;                  /* atomic bit ops */
 125        unsigned long           cache_validity;         /* bit mask */
 126
 127        /*
 128         * read_cache_jiffies is when we started read-caching this inode.
 129         * attrtimeo is for how long the cached information is assumed
 130         * to be valid. A successful attribute revalidation doubles
 131         * attrtimeo (up to acregmax/acdirmax), a failure resets it to
 132         * acregmin/acdirmin.
 133         *
 134         * We need to revalidate the cached attrs for this inode if
 135         *
 136         *      jiffies - read_cache_jiffies >= attrtimeo
 137         *
 138         * Please note the comparison is greater than or equal
 139         * so that zero timeout values can be specified.
 140         */
 141        unsigned long           read_cache_jiffies;
 142        unsigned long           attrtimeo;
 143        unsigned long           attrtimeo_timestamp;
 144
 145        unsigned long           attr_gencount;
 146        /* "Generation counter" for the attribute cache. This is
 147         * bumped whenever we update the metadata on the
 148         * server.
 149         */
 150        unsigned long           cache_change_attribute;
 151
 152        struct rb_root          access_cache;
 153        struct list_head        access_cache_entry_lru;
 154        struct list_head        access_cache_inode_lru;
 155
 156        /*
 157         * This is the cookie verifier used for NFSv3 readdir
 158         * operations
 159         */
 160        __be32                  cookieverf[2];
 161
 162        atomic_long_t           nrequests;
 163        struct nfs_mds_commit_info commit_info;
 164
 165        /* Open contexts for shared mmap writes */
 166        struct list_head        open_files;
 167
 168        /* Readers: in-flight sillydelete RPC calls */
 169        /* Writers: rmdir */
 170        struct rw_semaphore     rmdir_sem;
 171        struct mutex            commit_mutex;
 172
 173        /* track last access to cached pages */
 174        unsigned long           page_index;
 175
 176#if IS_ENABLED(CONFIG_NFS_V4)
 177        struct nfs4_cached_acl  *nfs4_acl;
 178        /* NFSv4 state */
 179        struct list_head        open_states;
 180        struct nfs_delegation __rcu *delegation;
 181        struct rw_semaphore     rwsem;
 182
 183        /* pNFS layout information */
 184        struct pnfs_layout_hdr *layout;
 185#endif /* CONFIG_NFS_V4*/
 186        /* how many bytes have been written/read and how many bytes queued up */
 187        __u64 write_io;
 188        __u64 read_io;
 189#ifdef CONFIG_NFS_FSCACHE
 190        struct fscache_cookie   *fscache;
 191#endif
 192        struct inode            vfs_inode;
 193
 194#ifdef CONFIG_NFS_V4_2
 195        struct nfs4_xattr_cache *xattr_cache;
 196#endif
 197};
 198
 199struct nfs4_copy_state {
 200        struct list_head        copies;
 201        struct list_head        src_copies;
 202        nfs4_stateid            stateid;
 203        struct completion       completion;
 204        uint64_t                count;
 205        struct nfs_writeverf    verf;
 206        int                     error;
 207        int                     flags;
 208        struct nfs4_state       *parent_src_state;
 209        struct nfs4_state       *parent_dst_state;
 210};
 211
 212/*
 213 * Access bit flags
 214 */
 215#define NFS_ACCESS_READ        0x0001
 216#define NFS_ACCESS_LOOKUP      0x0002
 217#define NFS_ACCESS_MODIFY      0x0004
 218#define NFS_ACCESS_EXTEND      0x0008
 219#define NFS_ACCESS_DELETE      0x0010
 220#define NFS_ACCESS_EXECUTE     0x0020
 221#define NFS_ACCESS_XAREAD      0x0040
 222#define NFS_ACCESS_XAWRITE     0x0080
 223#define NFS_ACCESS_XALIST      0x0100
 224
 225/*
 226 * Cache validity bit flags
 227 */
 228#define NFS_INO_INVALID_DATA    BIT(1)          /* cached data is invalid */
 229#define NFS_INO_INVALID_ATIME   BIT(2)          /* cached atime is invalid */
 230#define NFS_INO_INVALID_ACCESS  BIT(3)          /* cached access cred invalid */
 231#define NFS_INO_INVALID_ACL     BIT(4)          /* cached acls are invalid */
 232#define NFS_INO_REVAL_PAGECACHE BIT(5)          /* must revalidate pagecache */
 233#define NFS_INO_REVAL_FORCED    BIT(6)          /* force revalidation ignoring a delegation */
 234#define NFS_INO_INVALID_LABEL   BIT(7)          /* cached label is invalid */
 235#define NFS_INO_INVALID_CHANGE  BIT(8)          /* cached change is invalid */
 236#define NFS_INO_INVALID_CTIME   BIT(9)          /* cached ctime is invalid */
 237#define NFS_INO_INVALID_MTIME   BIT(10)         /* cached mtime is invalid */
 238#define NFS_INO_INVALID_SIZE    BIT(11)         /* cached size is invalid */
 239#define NFS_INO_INVALID_OTHER   BIT(12)         /* other attrs are invalid */
 240#define NFS_INO_DATA_INVAL_DEFER        \
 241                                BIT(13)         /* Deferred cache invalidation */
 242#define NFS_INO_INVALID_BLOCKS  BIT(14)         /* cached blocks are invalid */
 243#define NFS_INO_INVALID_XATTR   BIT(15)         /* xattrs are invalid */
 244
 245#define NFS_INO_INVALID_ATTR    (NFS_INO_INVALID_CHANGE \
 246                | NFS_INO_INVALID_CTIME \
 247                | NFS_INO_INVALID_MTIME \
 248                | NFS_INO_INVALID_SIZE \
 249                | NFS_INO_INVALID_OTHER)        /* inode metadata is invalid */
 250
 251/*
 252 * Bit offsets in flags field
 253 */
 254#define NFS_INO_ADVISE_RDPLUS   (0)             /* advise readdirplus */
 255#define NFS_INO_STALE           (1)             /* possible stale inode */
 256#define NFS_INO_ACL_LRU_SET     (2)             /* Inode is on the LRU list */
 257#define NFS_INO_INVALIDATING    (3)             /* inode is being invalidated */
 258#define NFS_INO_FSCACHE         (5)             /* inode can be cached by FS-Cache */
 259#define NFS_INO_FSCACHE_LOCK    (6)             /* FS-Cache cookie management lock */
 260#define NFS_INO_LAYOUTCOMMIT    (9)             /* layoutcommit required */
 261#define NFS_INO_LAYOUTCOMMITTING (10)           /* layoutcommit inflight */
 262#define NFS_INO_LAYOUTSTATS     (11)            /* layoutstats inflight */
 263#define NFS_INO_ODIRECT         (12)            /* I/O setting is O_DIRECT */
 264
 265static inline struct nfs_inode *NFS_I(const struct inode *inode)
 266{
 267        return container_of(inode, struct nfs_inode, vfs_inode);
 268}
 269
 270static inline struct nfs_server *NFS_SB(const struct super_block *s)
 271{
 272        return (struct nfs_server *)(s->s_fs_info);
 273}
 274
 275static inline struct nfs_fh *NFS_FH(const struct inode *inode)
 276{
 277        return &NFS_I(inode)->fh;
 278}
 279
 280static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
 281{
 282        return NFS_SB(inode->i_sb);
 283}
 284
 285static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
 286{
 287        return NFS_SERVER(inode)->client;
 288}
 289
 290static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
 291{
 292        return NFS_SERVER(inode)->nfs_client->rpc_ops;
 293}
 294
 295static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
 296{
 297        struct nfs_server *nfss = NFS_SERVER(inode);
 298        return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
 299}
 300
 301static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
 302{
 303        struct nfs_server *nfss = NFS_SERVER(inode);
 304        return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
 305}
 306
 307static inline int NFS_STALE(const struct inode *inode)
 308{
 309        return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
 310}
 311
 312static inline struct fscache_cookie *nfs_i_fscache(struct inode *inode)
 313{
 314#ifdef CONFIG_NFS_FSCACHE
 315        return NFS_I(inode)->fscache;
 316#else
 317        return NULL;
 318#endif
 319}
 320
 321static inline __u64 NFS_FILEID(const struct inode *inode)
 322{
 323        return NFS_I(inode)->fileid;
 324}
 325
 326static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
 327{
 328        NFS_I(inode)->fileid = fileid;
 329}
 330
 331static inline void nfs_mark_for_revalidate(struct inode *inode)
 332{
 333        struct nfs_inode *nfsi = NFS_I(inode);
 334
 335        spin_lock(&inode->i_lock);
 336        nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE
 337                | NFS_INO_INVALID_ACCESS
 338                | NFS_INO_INVALID_ACL
 339                | NFS_INO_INVALID_CHANGE
 340                | NFS_INO_INVALID_CTIME;
 341        if (S_ISDIR(inode->i_mode))
 342                nfsi->cache_validity |= NFS_INO_INVALID_DATA;
 343        spin_unlock(&inode->i_lock);
 344}
 345
 346static inline int nfs_server_capable(struct inode *inode, int cap)
 347{
 348        return NFS_SERVER(inode)->caps & cap;
 349}
 350
 351/**
 352 * nfs_save_change_attribute - Returns the inode attribute change cookie
 353 * @dir - pointer to parent directory inode
 354 * The "cache change attribute" is updated when we need to revalidate
 355 * our dentry cache after a directory was seen to change on the server.
 356 */
 357static inline unsigned long nfs_save_change_attribute(struct inode *dir)
 358{
 359        return NFS_I(dir)->cache_change_attribute;
 360}
 361
 362/*
 363 * linux/fs/nfs/inode.c
 364 */
 365extern int nfs_sync_mapping(struct address_space *mapping);
 366extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
 367extern void nfs_zap_caches(struct inode *);
 368extern void nfs_set_inode_stale(struct inode *inode);
 369extern void nfs_invalidate_atime(struct inode *);
 370extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
 371                                struct nfs_fattr *, struct nfs4_label *);
 372struct inode *nfs_ilookup(struct super_block *sb, struct nfs_fattr *, struct nfs_fh *);
 373extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
 374extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
 375extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
 376extern int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr);
 377extern int nfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
 378extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
 379extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
 380extern int nfs_permission(struct inode *, int);
 381extern int nfs_open(struct inode *, struct file *);
 382extern int nfs_attribute_cache_expired(struct inode *inode);
 383extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
 384extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
 385extern bool nfs_mapping_need_revalidate_inode(struct inode *inode);
 386extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
 387extern int nfs_revalidate_mapping_rcu(struct inode *inode);
 388extern int nfs_setattr(struct dentry *, struct iattr *);
 389extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, struct nfs_fattr *);
 390extern void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
 391                                struct nfs4_label *label);
 392extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
 393extern void put_nfs_open_context(struct nfs_open_context *ctx);
 394extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, const struct cred *cred, fmode_t mode);
 395extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode, struct file *filp);
 396extern void nfs_inode_attach_open_context(struct nfs_open_context *ctx);
 397extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
 398extern void nfs_file_clear_open_context(struct file *flip);
 399extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
 400extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
 401extern u64 nfs_compat_user_ino64(u64 fileid);
 402extern void nfs_fattr_init(struct nfs_fattr *fattr);
 403extern void nfs_fattr_set_barrier(struct nfs_fattr *fattr);
 404extern unsigned long nfs_inc_attr_generation_counter(void);
 405
 406extern struct nfs_fattr *nfs_alloc_fattr(void);
 407
 408static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
 409{
 410        kfree(fattr);
 411}
 412
 413extern struct nfs_fh *nfs_alloc_fhandle(void);
 414
 415static inline void nfs_free_fhandle(const struct nfs_fh *fh)
 416{
 417        kfree(fh);
 418}
 419
 420#ifdef NFS_DEBUG
 421extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
 422static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
 423{
 424        return _nfs_display_fhandle_hash(fh);
 425}
 426extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
 427#define nfs_display_fhandle(fh, caption)                        \
 428        do {                                                    \
 429                if (unlikely(nfs_debug & NFSDBG_FACILITY))      \
 430                        _nfs_display_fhandle(fh, caption);      \
 431        } while (0)
 432#else
 433static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
 434{
 435        return 0;
 436}
 437static inline void nfs_display_fhandle(const struct nfs_fh *fh,
 438                                       const char *caption)
 439{
 440}
 441#endif
 442
 443/*
 444 * linux/fs/nfs/nfsroot.c
 445 */
 446extern int  nfs_root_data(char **root_device, char **root_data); /*__init*/
 447/* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
 448extern __be32 root_nfs_parse_addr(char *name); /*__init*/
 449
 450/*
 451 * linux/fs/nfs/file.c
 452 */
 453extern const struct file_operations nfs_file_operations;
 454#if IS_ENABLED(CONFIG_NFS_V4)
 455extern const struct file_operations nfs4_file_operations;
 456#endif /* CONFIG_NFS_V4 */
 457extern const struct address_space_operations nfs_file_aops;
 458extern const struct address_space_operations nfs_dir_aops;
 459
 460static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
 461{
 462        return filp->private_data;
 463}
 464
 465static inline const struct cred *nfs_file_cred(struct file *file)
 466{
 467        if (file != NULL) {
 468                struct nfs_open_context *ctx =
 469                        nfs_file_open_context(file);
 470                if (ctx)
 471                        return ctx->cred;
 472        }
 473        return NULL;
 474}
 475
 476/*
 477 * linux/fs/nfs/direct.c
 478 */
 479extern ssize_t nfs_direct_IO(struct kiocb *, struct iov_iter *);
 480extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
 481                        struct iov_iter *iter);
 482extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
 483                        struct iov_iter *iter);
 484
 485/*
 486 * linux/fs/nfs/dir.c
 487 */
 488extern const struct file_operations nfs_dir_operations;
 489extern const struct dentry_operations nfs_dentry_operations;
 490
 491extern void nfs_force_lookup_revalidate(struct inode *dir);
 492extern void nfs_set_verifier(struct dentry * dentry, unsigned long verf);
 493#if IS_ENABLED(CONFIG_NFS_V4)
 494extern void nfs_clear_verifier_delegated(struct inode *inode);
 495#endif /* IS_ENABLED(CONFIG_NFS_V4) */
 496extern struct dentry *nfs_add_or_obtain(struct dentry *dentry,
 497                        struct nfs_fh *fh, struct nfs_fattr *fattr,
 498                        struct nfs4_label *label);
 499extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh,
 500                        struct nfs_fattr *fattr, struct nfs4_label *label);
 501extern int nfs_may_open(struct inode *inode, const struct cred *cred, int openflags);
 502extern void nfs_access_zap_cache(struct inode *inode);
 503extern int nfs_access_get_cached(struct inode *inode, const struct cred *cred, struct nfs_access_entry *res,
 504                                 bool may_block);
 505
 506/*
 507 * linux/fs/nfs/symlink.c
 508 */
 509extern const struct inode_operations nfs_symlink_inode_operations;
 510
 511/*
 512 * linux/fs/nfs/sysctl.c
 513 */
 514#ifdef CONFIG_SYSCTL
 515extern int nfs_register_sysctl(void);
 516extern void nfs_unregister_sysctl(void);
 517#else
 518#define nfs_register_sysctl() 0
 519#define nfs_unregister_sysctl() do { } while(0)
 520#endif
 521
 522/*
 523 * linux/fs/nfs/namespace.c
 524 */
 525extern const struct inode_operations nfs_mountpoint_inode_operations;
 526extern const struct inode_operations nfs_referral_inode_operations;
 527extern int nfs_mountpoint_expiry_timeout;
 528extern void nfs_release_automount_timer(void);
 529
 530/*
 531 * linux/fs/nfs/unlink.c
 532 */
 533extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
 534
 535/*
 536 * linux/fs/nfs/write.c
 537 */
 538extern int  nfs_congestion_kb;
 539extern int  nfs_writepage(struct page *page, struct writeback_control *wbc);
 540extern int  nfs_writepages(struct address_space *, struct writeback_control *);
 541extern int  nfs_flush_incompatible(struct file *file, struct page *page);
 542extern int  nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
 543
 544/*
 545 * Try to write back everything synchronously (but check the
 546 * return value!)
 547 */
 548extern int nfs_sync_inode(struct inode *inode);
 549extern int nfs_wb_all(struct inode *inode);
 550extern int nfs_wb_page(struct inode *inode, struct page *page);
 551extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
 552extern int  nfs_commit_inode(struct inode *, int);
 553extern struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail);
 554extern void nfs_commit_free(struct nfs_commit_data *data);
 555
 556static inline int
 557nfs_have_writebacks(struct inode *inode)
 558{
 559        return atomic_long_read(&NFS_I(inode)->nrequests) != 0;
 560}
 561
 562/*
 563 * linux/fs/nfs/read.c
 564 */
 565extern int  nfs_readpage(struct file *, struct page *);
 566extern int  nfs_readpages(struct file *, struct address_space *,
 567                struct list_head *, unsigned);
 568extern int  nfs_readpage_async(struct nfs_open_context *, struct inode *,
 569                               struct page *);
 570
 571/*
 572 * inline functions
 573 */
 574
 575static inline loff_t nfs_size_to_loff_t(__u64 size)
 576{
 577        return min_t(u64, size, OFFSET_MAX);
 578}
 579
 580static inline ino_t
 581nfs_fileid_to_ino_t(u64 fileid)
 582{
 583        ino_t ino = (ino_t) fileid;
 584        if (sizeof(ino_t) < sizeof(u64))
 585                ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
 586        return ino;
 587}
 588
 589#define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
 590
 591
 592# undef ifdebug
 593# ifdef NFS_DEBUG
 594#  define ifdebug(fac)          if (unlikely(nfs_debug & NFSDBG_##fac))
 595#  define NFS_IFDEBUG(x)        x
 596# else
 597#  define ifdebug(fac)          if (0)
 598#  define NFS_IFDEBUG(x)
 599# endif
 600#endif
 601