include/linux/nfs_fs.h

   1 /*
   2  *  linux/include/linux/nfs_fs.h
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  OS-specific nfs filesystem definitions and declarations
   7  */
   8 #ifndef _LINUX_NFS_FS_H
   9 #define _LINUX_NFS_FS_H
  10
  11 #include <uapi/linux/nfs_fs.h>
  12
  13
  14 /*
  15  * Enable dprintk() debugging support for nfs client.
  16  */
  17 #ifdef CONFIG_NFS_DEBUG
  18 # define NFS_DEBUG
  19 #endif
  20
  21 #include <linux/in.h>
  22 #include <linux/mm.h>
  23 #include <linux/pagemap.h>
  24 #include <linux/rbtree.h>
  25 #include <linux/rwsem.h>
  26 #include <linux/wait.h>
  27
  28 #include <linux/sunrpc/debug.h>
  29 #include <linux/sunrpc/auth.h>
  30 #include <linux/sunrpc/clnt.h>
  31
  32 #include <linux/nfs.h>
  33 #include <linux/nfs2.h>
  34 #include <linux/nfs3.h>
  35 #include <linux/nfs4.h>
  36 #include <linux/nfs_xdr.h>
  37 #include <linux/nfs_fs_sb.h>
  38
  39 #include <linux/mempool.h>
  40
  41 /*
  42  * These are the default flags for swap requests
  43  */
  44 #define NFS_RPC_SWAPFLAGS               (RPC_TASK_SWAPPER|RPC_TASK_ROOTCREDS)
  45
  46 /*
  47  * NFSv3/v4 Access mode cache entry
  48  */
  49 struct nfs_access_entry {
  50         struct rb_node          rb_node;
  51         struct list_head        lru;
  52         unsigned long           jiffies;
  53         struct rpc_cred *       cred;
  54         int                     mask;
  55 };
  56
  57 struct nfs_lockowner {
  58         fl_owner_t l_owner;
  59         pid_t l_pid;
  60 };
  61
  62 #define NFS_IO_INPROGRESS 0
  63 struct nfs_io_counter {
  64         unsigned long flags;
  65         atomic_t io_count;
  66 };
  67
  68 struct nfs_lock_context {
  69         atomic_t count;
  70         struct list_head list;
  71         struct nfs_open_context *open_context;
  72         struct nfs_lockowner lockowner;
  73         struct nfs_io_counter io_count;
  74 };
  75
  76 struct nfs4_state;
  77 struct nfs_open_context {
  78         struct nfs_lock_context lock_context;
  79         struct dentry *dentry;
  80         struct rpc_cred *cred;
  81         struct nfs4_state *state;
  82         fmode_t mode;
  83
  84         unsigned long flags;
  85 #define NFS_CONTEXT_ERROR_WRITE         (0)
  86 #define NFS_CONTEXT_RESEND_WRITES       (1)
  87 #define NFS_CONTEXT_BAD                 (2)
  88         int error;
  89
  90         struct list_head list;
  91         struct nfs4_threshold   *mdsthreshold;
  92 };
  93
  94 struct nfs_open_dir_context {
  95         struct rpc_cred *cred;
  96         unsigned long attr_gencount;
  97         __u64 dir_cookie;
  98         __u64 dup_cookie;
  99         signed char duped;
 100 };
 101
 102 /*
 103  * NFSv4 delegation
 104  */
 105 struct nfs_delegation;
 106
 107 struct posix_acl;
 108
 109 /*
 110  * nfs fs inode data in memory
 111  */
 112 struct nfs_inode {
 113         /*
 114          * The 64bit 'inode number'
 115          */
 116         __u64 fileid;
 117
 118         /*
 119          * NFS file handle
 120          */
 121         struct nfs_fh           fh;
 122
 123         /*
 124          * Various flags
 125          */
 126         unsigned long           flags;                  /* atomic bit ops */
 127         unsigned long           cache_validity;         /* bit mask */
 128
 129         /*
 130          * read_cache_jiffies is when we started read-caching this inode.
 131          * attrtimeo is for how long the cached information is assumed
 132          * to be valid. A successful attribute revalidation doubles
 133          * attrtimeo (up to acregmax/acdirmax), a failure resets it to
 134          * acregmin/acdirmin.
 135          *
 136          * We need to revalidate the cached attrs for this inode if
 137          *
 138          *      jiffies - read_cache_jiffies >= attrtimeo
 139          *
 140          * Please note the comparison is greater than or equal
 141          * so that zero timeout values can be specified.
 142          */
 143         unsigned long           read_cache_jiffies;
 144         unsigned long           attrtimeo;
 145         unsigned long           attrtimeo_timestamp;
 146
 147         unsigned long           attr_gencount;
 148         /* "Generation counter" for the attribute cache. This is
 149          * bumped whenever we update the metadata on the
 150          * server.
 151          */
 152         unsigned long           cache_change_attribute;
 153
 154         struct rb_root          access_cache;
 155         struct list_head        access_cache_entry_lru;
 156         struct list_head        access_cache_inode_lru;
 157
 158         /*
 159          * This is the cookie verifier used for NFSv3 readdir
 160          * operations
 161          */
 162         __be32                  cookieverf[2];
 163
 164         unsigned long           npages;
 165         struct nfs_mds_commit_info commit_info;
 166
 167         /* Open contexts for shared mmap writes */
 168         struct list_head        open_files;
 169
 170         /* Number of in-flight sillydelete RPC calls */
 171         atomic_t                silly_count;
 172         /* List of deferred sillydelete requests */
 173         struct hlist_head       silly_list;
 174         wait_queue_head_t       waitqueue;
 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         fmode_t                  delegation_state;
 182         struct rw_semaphore     rwsem;
 183
 184         /* pNFS layout information */
 185         struct pnfs_layout_hdr *layout;
 186 #endif /* CONFIG_NFS_V4*/
 187         /* how many bytes have been written/read and how many bytes queued up */
 188         __u64 write_io;
 189         __u64 read_io;
 190 #ifdef CONFIG_NFS_FSCACHE
 191         struct fscache_cookie   *fscache;
 192 #endif
 193         struct inode            vfs_inode;
 194 };
 195
 196 /*
 197  * Cache validity bit flags
 198  */
 199 #define NFS_INO_INVALID_ATTR    0x0001          /* cached attrs are invalid */
 200 #define NFS_INO_INVALID_DATA    0x0002          /* cached data is invalid */
 201 #define NFS_INO_INVALID_ATIME   0x0004          /* cached atime is invalid */
 202 #define NFS_INO_INVALID_ACCESS  0x0008          /* cached access cred invalid */
 203 #define NFS_INO_INVALID_ACL     0x0010          /* cached acls are invalid */
 204 #define NFS_INO_REVAL_PAGECACHE 0x0020          /* must revalidate pagecache */
 205 #define NFS_INO_REVAL_FORCED    0x0040          /* force revalidation ignoring a delegation */
 206 #define NFS_INO_INVALID_LABEL   0x0080          /* cached label is invalid */
 207
 208 /*
 209  * Bit offsets in flags field
 210  */
 211 #define NFS_INO_ADVISE_RDPLUS   (0)             /* advise readdirplus */
 212 #define NFS_INO_STALE           (1)             /* possible stale inode */
 213 #define NFS_INO_ACL_LRU_SET     (2)             /* Inode is on the LRU list */
 214 #define NFS_INO_INVALIDATING    (3)             /* inode is being invalidated */
 215 #define NFS_INO_FLUSHING        (4)             /* inode is flushing out data */
 216 #define NFS_INO_FSCACHE         (5)             /* inode can be cached by FS-Cache */
 217 #define NFS_INO_FSCACHE_LOCK    (6)             /* FS-Cache cookie management lock */
 218 #define NFS_INO_COMMIT          (7)             /* inode is committing unstable writes */
 219 #define NFS_INO_LAYOUTCOMMIT    (9)             /* layoutcommit required */
 220 #define NFS_INO_LAYOUTCOMMITTING (10)           /* layoutcommit inflight */
 221
 222 static inline struct nfs_inode *NFS_I(const struct inode *inode)
 223 {
 224         return container_of(inode, struct nfs_inode, vfs_inode);
 225 }
 226
 227 static inline struct nfs_server *NFS_SB(const struct super_block *s)
 228 {
 229         return (struct nfs_server *)(s->s_fs_info);
 230 }
 231
 232 static inline struct nfs_fh *NFS_FH(const struct inode *inode)
 233 {
 234         return &NFS_I(inode)->fh;
 235 }
 236
 237 static inline struct nfs_server *NFS_SERVER(const struct inode *inode)
 238 {
 239         return NFS_SB(inode->i_sb);
 240 }
 241
 242 static inline struct rpc_clnt *NFS_CLIENT(const struct inode *inode)
 243 {
 244         return NFS_SERVER(inode)->client;
 245 }
 246
 247 static inline const struct nfs_rpc_ops *NFS_PROTO(const struct inode *inode)
 248 {
 249         return NFS_SERVER(inode)->nfs_client->rpc_ops;
 250 }
 251
 252 static inline unsigned NFS_MINATTRTIMEO(const struct inode *inode)
 253 {
 254         struct nfs_server *nfss = NFS_SERVER(inode);
 255         return S_ISDIR(inode->i_mode) ? nfss->acdirmin : nfss->acregmin;
 256 }
 257
 258 static inline unsigned NFS_MAXATTRTIMEO(const struct inode *inode)
 259 {
 260         struct nfs_server *nfss = NFS_SERVER(inode);
 261         return S_ISDIR(inode->i_mode) ? nfss->acdirmax : nfss->acregmax;
 262 }
 263
 264 static inline int NFS_STALE(const struct inode *inode)
 265 {
 266         return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
 267 }
 268
 269 static inline struct fscache_cookie *nfs_i_fscache(struct inode *inode)
 270 {
 271 #ifdef CONFIG_NFS_FSCACHE
 272         return NFS_I(inode)->fscache;
 273 #else
 274         return NULL;
 275 #endif
 276 }
 277
 278 static inline __u64 NFS_FILEID(const struct inode *inode)
 279 {
 280         return NFS_I(inode)->fileid;
 281 }
 282
 283 static inline void set_nfs_fileid(struct inode *inode, __u64 fileid)
 284 {
 285         NFS_I(inode)->fileid = fileid;
 286 }
 287
 288 static inline void nfs_mark_for_revalidate(struct inode *inode)
 289 {
 290         struct nfs_inode *nfsi = NFS_I(inode);
 291
 292         spin_lock(&inode->i_lock);
 293         nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS;
 294         if (S_ISDIR(inode->i_mode))
 295                 nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA;
 296         spin_unlock(&inode->i_lock);
 297 }
 298
 299 static inline int nfs_server_capable(struct inode *inode, int cap)
 300 {
 301         return NFS_SERVER(inode)->caps & cap;
 302 }
 303
 304 static inline void nfs_set_verifier(struct dentry * dentry, unsigned long verf)
 305 {
 306         dentry->d_time = verf;
 307 }
 308
 309 /**
 310  * nfs_save_change_attribute - Returns the inode attribute change cookie
 311  * @dir - pointer to parent directory inode
 312  * The "change attribute" is updated every time we finish an operation
 313  * that will result in a metadata change on the server.
 314  */
 315 static inline unsigned long nfs_save_change_attribute(struct inode *dir)
 316 {
 317         return NFS_I(dir)->cache_change_attribute;
 318 }
 319
 320 /**
 321  * nfs_verify_change_attribute - Detects NFS remote directory changes
 322  * @dir - pointer to parent directory inode
 323  * @chattr - previously saved change attribute
 324  * Return "false" if the verifiers doesn't match the change attribute.
 325  * This would usually indicate that the directory contents have changed on
 326  * the server, and that any dentries need revalidating.
 327  */
 328 static inline int nfs_verify_change_attribute(struct inode *dir, unsigned long chattr)
 329 {
 330         return chattr == NFS_I(dir)->cache_change_attribute;
 331 }
 332
 333 /*
 334  * linux/fs/nfs/inode.c
 335  */
 336 extern int nfs_sync_mapping(struct address_space *mapping);
 337 extern void nfs_zap_mapping(struct inode *inode, struct address_space *mapping);
 338 extern void nfs_zap_caches(struct inode *);
 339 extern void nfs_invalidate_atime(struct inode *);
 340 extern struct inode *nfs_fhget(struct super_block *, struct nfs_fh *,
 341                                 struct nfs_fattr *, struct nfs4_label *);
 342 extern int nfs_refresh_inode(struct inode *, struct nfs_fattr *);
 343 extern int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr);
 344 extern int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr);
 345 extern int nfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
 346 extern void nfs_access_add_cache(struct inode *, struct nfs_access_entry *);
 347 extern void nfs_access_set_mask(struct nfs_access_entry *, u32);
 348 extern int nfs_permission(struct inode *, int);
 349 extern int nfs_open(struct inode *, struct file *);
 350 extern int nfs_release(struct inode *, struct file *);
 351 extern int nfs_attribute_timeout(struct inode *inode);
 352 extern int nfs_attribute_cache_expired(struct inode *inode);
 353 extern int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode);
 354 extern int __nfs_revalidate_inode(struct nfs_server *, struct inode *);
 355 extern int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping);
 356 extern int nfs_setattr(struct dentry *, struct iattr *);
 357 extern void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr);
 358 extern void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
 359                                 struct nfs4_label *label);
 360 extern struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx);
 361 extern void put_nfs_open_context(struct nfs_open_context *ctx);
 362 extern struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode);
 363 extern struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode);
 364 extern void nfs_inode_attach_open_context(struct nfs_open_context *ctx);
 365 extern void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx);
 366 extern struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx);
 367 extern void nfs_put_lock_context(struct nfs_lock_context *l_ctx);
 368 extern u64 nfs_compat_user_ino64(u64 fileid);
 369 extern void nfs_fattr_init(struct nfs_fattr *fattr);
 370 extern unsigned long nfs_inc_attr_generation_counter(void);
 371
 372 extern struct nfs_fattr *nfs_alloc_fattr(void);
 373
 374 static inline void nfs_free_fattr(const struct nfs_fattr *fattr)
 375 {
 376         kfree(fattr);
 377 }
 378
 379 extern struct nfs_fh *nfs_alloc_fhandle(void);
 380
 381 static inline void nfs_free_fhandle(const struct nfs_fh *fh)
 382 {
 383         kfree(fh);
 384 }
 385
 386 #ifdef NFS_DEBUG
 387 extern u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh);
 388 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
 389 {
 390         return _nfs_display_fhandle_hash(fh);
 391 }
 392 extern void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption);
 393 #define nfs_display_fhandle(fh, caption)                        \
 394         do {                                                    \
 395                 if (unlikely(nfs_debug & NFSDBG_FACILITY))      \
 396                         _nfs_display_fhandle(fh, caption);      \
 397         } while (0)
 398 #else
 399 static inline u32 nfs_display_fhandle_hash(const struct nfs_fh *fh)
 400 {
 401         return 0;
 402 }
 403 static inline void nfs_display_fhandle(const struct nfs_fh *fh,
 404                                        const char *caption)
 405 {
 406 }
 407 #endif
 408
 409 /*
 410  * linux/fs/nfs/nfsroot.c
 411  */
 412 extern int  nfs_root_data(char **root_device, char **root_data); /*__init*/
 413 /* linux/net/ipv4/ipconfig.c: trims ip addr off front of name, too. */
 414 extern __be32 root_nfs_parse_addr(char *name); /*__init*/
 415
 416 /*
 417  * linux/fs/nfs/file.c
 418  */
 419 extern const struct file_operations nfs_file_operations;
 420 #if IS_ENABLED(CONFIG_NFS_V4)
 421 extern const struct file_operations nfs4_file_operations;
 422 #endif /* CONFIG_NFS_V4 */
 423 extern const struct address_space_operations nfs_file_aops;
 424 extern const struct address_space_operations nfs_dir_aops;
 425
 426 static inline struct nfs_open_context *nfs_file_open_context(struct file *filp)
 427 {
 428         return filp->private_data;
 429 }
 430
 431 static inline struct rpc_cred *nfs_file_cred(struct file *file)
 432 {
 433         if (file != NULL) {
 434                 struct nfs_open_context *ctx =
 435                         nfs_file_open_context(file);
 436                 if (ctx)
 437                         return ctx->cred;
 438         }
 439         return NULL;
 440 }
 441
 442 /*
 443  * linux/fs/nfs/xattr.c
 444  */
 445 #ifdef CONFIG_NFS_V3_ACL
 446 extern ssize_t nfs3_listxattr(struct dentry *, char *, size_t);
 447 extern ssize_t nfs3_getxattr(struct dentry *, const char *, void *, size_t);
 448 extern int nfs3_setxattr(struct dentry *, const char *,
 449                         const void *, size_t, int);
 450 extern int nfs3_removexattr (struct dentry *, const char *name);
 451 #else
 452 # define nfs3_listxattr NULL
 453 # define nfs3_getxattr NULL
 454 # define nfs3_setxattr NULL
 455 # define nfs3_removexattr NULL
 456 #endif
 457
 458 /*
 459  * linux/fs/nfs/direct.c
 460  */
 461 extern ssize_t nfs_direct_IO(int, struct kiocb *, const struct iovec *, loff_t,
 462                         unsigned long);
 463 extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
 464                         const struct iovec *iov, unsigned long nr_segs,
 465                         loff_t pos, bool uio);
 466 extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
 467                         const struct iovec *iov, unsigned long nr_segs,
 468                         loff_t pos, bool uio);
 469
 470 /*
 471  * linux/fs/nfs/dir.c
 472  */
 473 extern const struct file_operations nfs_dir_operations;
 474 extern const struct dentry_operations nfs_dentry_operations;
 475
 476 extern void nfs_force_lookup_revalidate(struct inode *dir);
 477 extern int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fh,
 478                         struct nfs_fattr *fattr, struct nfs4_label *label);
 479 extern int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags);
 480 extern void nfs_access_zap_cache(struct inode *inode);
 481
 482 /*
 483  * linux/fs/nfs/symlink.c
 484  */
 485 extern const struct inode_operations nfs_symlink_inode_operations;
 486
 487 /*
 488  * linux/fs/nfs/sysctl.c
 489  */
 490 #ifdef CONFIG_SYSCTL
 491 extern int nfs_register_sysctl(void);
 492 extern void nfs_unregister_sysctl(void);
 493 #else
 494 #define nfs_register_sysctl() 0
 495 #define nfs_unregister_sysctl() do { } while(0)
 496 #endif
 497
 498 /*
 499  * linux/fs/nfs/namespace.c
 500  */
 501 extern const struct inode_operations nfs_mountpoint_inode_operations;
 502 extern const struct inode_operations nfs_referral_inode_operations;
 503 extern int nfs_mountpoint_expiry_timeout;
 504 extern void nfs_release_automount_timer(void);
 505
 506 /*
 507  * linux/fs/nfs/unlink.c
 508  */
 509 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
 510 extern void nfs_wait_on_sillyrename(struct dentry *dentry);
 511 extern void nfs_block_sillyrename(struct dentry *dentry);
 512 extern void nfs_unblock_sillyrename(struct dentry *dentry);
 513 extern int  nfs_sillyrename(struct inode *dir, struct dentry *dentry);
 514
 515 /*
 516  * linux/fs/nfs/write.c
 517  */
 518 extern int  nfs_congestion_kb;
 519 extern int  nfs_writepage(struct page *page, struct writeback_control *wbc);
 520 extern int  nfs_writepages(struct address_space *, struct writeback_control *);
 521 extern int  nfs_flush_incompatible(struct file *file, struct page *page);
 522 extern int  nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
 523 extern void nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
 524
 525 /*
 526  * Try to write back everything synchronously (but check the
 527  * return value!)
 528  */
 529 extern int nfs_wb_all(struct inode *inode);
 530 extern int nfs_wb_page(struct inode *inode, struct page* page);
 531 extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
 532 #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 533 extern int  nfs_commit_inode(struct inode *, int);
 534 extern struct nfs_commit_data *nfs_commitdata_alloc(void);
 535 extern void nfs_commit_free(struct nfs_commit_data *data);
 536 #else
 537 static inline int
 538 nfs_commit_inode(struct inode *inode, int how)
 539 {
 540         return 0;
 541 }
 542 #endif
 543
 544 static inline int
 545 nfs_have_writebacks(struct inode *inode)
 546 {
 547         return NFS_I(inode)->npages != 0;
 548 }
 549
 550 /*
 551  * linux/fs/nfs/read.c
 552  */
 553 extern int  nfs_readpage(struct file *, struct page *);
 554 extern int  nfs_readpages(struct file *, struct address_space *,
 555                 struct list_head *, unsigned);
 556 extern int  nfs_readpage_result(struct rpc_task *, struct nfs_read_data *);
 557 extern int  nfs_readpage_async(struct nfs_open_context *, struct inode *,
 558                                struct page *);
 559
 560 /*
 561  * linux/fs/nfs3proc.c
 562  */
 563 #ifdef CONFIG_NFS_V3_ACL
 564 extern struct posix_acl *nfs3_get_acl(struct inode *inode, int type);
 565 extern int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type);
 566 extern int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 567                 struct posix_acl *dfacl);
 568 extern const struct xattr_handler *nfs3_xattr_handlers[];
 569 #else
 570 static inline int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 571                 struct posix_acl *dfacl)
 572 {
 573         return 0;
 574 }
 575 #endif /* CONFIG_NFS_V3_ACL */
 576
 577 /*
 578  * inline functions
 579  */
 580
 581 static inline loff_t nfs_size_to_loff_t(__u64 size)
 582 {
 583         if (size > (__u64) OFFSET_MAX - 1)
 584                 return OFFSET_MAX - 1;
 585         return (loff_t) size;
 586 }
 587
 588 static inline ino_t
 589 nfs_fileid_to_ino_t(u64 fileid)
 590 {
 591         ino_t ino = (ino_t) fileid;
 592         if (sizeof(ino_t) < sizeof(u64))
 593                 ino ^= fileid >> (sizeof(u64)-sizeof(ino_t)) * 8;
 594         return ino;
 595 }
 596
 597 #define NFS_JUKEBOX_RETRY_TIME (5 * HZ)
 598
 599
 600 # undef ifdebug
 601 # ifdef NFS_DEBUG
 602 #  define ifdebug(fac)          if (unlikely(nfs_debug & NFSDBG_##fac))
 603 #  define NFS_IFDEBUG(x)        x
 604 # else
 605 #  define ifdebug(fac)          if (0)
 606 #  define NFS_IFDEBUG(x)
 607 # endif
 608 #endif