fs/nfs/internal.h

   1 /*
   2  * NFS internal definitions
   3  */
   4
   5 #include "nfs4_fs.h"
   6 #include <linux/mount.h>
   7 #include <linux/security.h>
   8
   9 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
  10
  11 struct nfs_string;
  12
  13 /* Maximum number of readahead requests
  14  * FIXME: this should really be a sysctl so that users may tune it to suit
  15  *        their needs. People that do NFS over a slow network, might for
  16  *        instance want to reduce it to something closer to 1 for improved
  17  *        interactive response.
  18  */
  19 #define NFS_MAX_READAHEAD       (RPC_DEF_SLOT_TABLE - 1)
  20
  21 /*
  22  * Determine if sessions are in use.
  23  */
  24 static inline int nfs4_has_session(const struct nfs_client *clp)
  25 {
  26 #ifdef CONFIG_NFS_V4_1
  27         if (clp->cl_session)
  28                 return 1;
  29 #endif /* CONFIG_NFS_V4_1 */
  30         return 0;
  31 }
  32
  33 static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
  34 {
  35 #ifdef CONFIG_NFS_V4_1
  36         if (nfs4_has_session(clp))
  37                 return (clp->cl_session->flags & SESSION4_PERSIST);
  38 #endif /* CONFIG_NFS_V4_1 */
  39         return 0;
  40 }
  41
  42 static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
  43 {
  44         if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
  45                 fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
  46 }
  47
  48 static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
  49 {
  50         if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
  51             (((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
  52              ((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
  53                 return 0;
  54
  55         fattr->fileid = fattr->mounted_on_fileid;
  56         return 1;
  57 }
  58
  59 struct nfs_clone_mount {
  60         const struct super_block *sb;
  61         const struct dentry *dentry;
  62         struct nfs_fh *fh;
  63         struct nfs_fattr *fattr;
  64         char *hostname;
  65         char *mnt_path;
  66         struct sockaddr *addr;
  67         size_t addrlen;
  68         rpc_authflavor_t authflavor;
  69 };
  70
  71 /*
  72  * Note: RFC 1813 doesn't limit the number of auth flavors that
  73  * a server can return, so make something up.
  74  */
  75 #define NFS_MAX_SECFLAVORS      (12)
  76
  77 /*
  78  * Value used if the user did not specify a port value.
  79  */
  80 #define NFS_UNSPEC_PORT         (-1)
  81
  82 /*
  83  * Maximum number of pages that readdir can use for creating
  84  * a vmapped array of pages.
  85  */
  86 #define NFS_MAX_READDIR_PAGES 8
  87
  88 struct nfs_client_initdata {
  89         unsigned long init_flags;
  90         const char *hostname;
  91         const struct sockaddr *addr;
  92         size_t addrlen;
  93         struct nfs_subversion *nfs_mod;
  94         int proto;
  95         u32 minorversion;
  96         struct net *net;
  97 };
  98
  99 /*
 100  * In-kernel mount arguments
 101  */
 102 struct nfs_parsed_mount_data {
 103         int                     flags;
 104         int                     rsize, wsize;
 105         int                     timeo, retrans;
 106         int                     acregmin, acregmax,
 107                                 acdirmin, acdirmax;
 108         int                     namlen;
 109         unsigned int            options;
 110         unsigned int            bsize;
 111         unsigned int            auth_flavor_len;
 112         rpc_authflavor_t        auth_flavors[1];
 113         char                    *client_address;
 114         unsigned int            version;
 115         unsigned int            minorversion;
 116         char                    *fscache_uniq;
 117         bool                    need_mount;
 118
 119         struct {
 120                 struct sockaddr_storage address;
 121                 size_t                  addrlen;
 122                 char                    *hostname;
 123                 u32                     version;
 124                 int                     port;
 125                 unsigned short          protocol;
 126         } mount_server;
 127
 128         struct {
 129                 struct sockaddr_storage address;
 130                 size_t                  addrlen;
 131                 char                    *hostname;
 132                 char                    *export_path;
 133                 int                     port;
 134                 unsigned short          protocol;
 135         } nfs_server;
 136
 137         struct security_mnt_opts lsm_opts;
 138         struct net              *net;
 139 };
 140
 141 /* mount_clnt.c */
 142 struct nfs_mount_request {
 143         struct sockaddr         *sap;
 144         size_t                  salen;
 145         char                    *hostname;
 146         char                    *dirpath;
 147         u32                     version;
 148         unsigned short          protocol;
 149         struct nfs_fh           *fh;
 150         int                     noresvport;
 151         unsigned int            *auth_flav_len;
 152         rpc_authflavor_t        *auth_flavs;
 153         struct net              *net;
 154 };
 155
 156 struct nfs_mount_info {
 157         void (*fill_super)(struct super_block *, struct nfs_mount_info *);
 158         int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
 159         struct nfs_parsed_mount_data *parsed;
 160         struct nfs_clone_mount *cloned;
 161         struct nfs_fh *mntfh;
 162 };
 163
 164 extern int nfs_mount(struct nfs_mount_request *info);
 165 extern void nfs_umount(const struct nfs_mount_request *info);
 166
 167 /* client.c */
 168 extern const struct rpc_program nfs_program;
 169 extern void nfs_clients_init(struct net *net);
 170 extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
 171 int nfs_create_rpc_client(struct nfs_client *, const struct rpc_timeout *, rpc_authflavor_t);
 172 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
 173                                   const struct rpc_timeout *, const char *,
 174                                   rpc_authflavor_t);
 175 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
 176 void nfs_server_insert_lists(struct nfs_server *);
 177 void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
 178 int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
 179                 rpc_authflavor_t);
 180 struct nfs_server *nfs_alloc_server(void);
 181 void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
 182
 183 extern void nfs_cleanup_cb_ident_idr(struct net *);
 184 extern void nfs_put_client(struct nfs_client *);
 185 extern void nfs_free_client(struct nfs_client *);
 186 extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
 187 extern struct nfs_client *
 188 nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
 189                                 struct nfs4_sessionid *);
 190 extern struct nfs_server *nfs_create_server(
 191                                         const struct nfs_parsed_mount_data *,
 192                                         struct nfs_fh *,
 193                                         struct nfs_subversion *);
 194 extern struct nfs_server *nfs4_create_server(
 195                                         const struct nfs_parsed_mount_data *,
 196                                         struct nfs_fh *);
 197 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
 198                                                       struct nfs_fh *);
 199 extern void nfs_free_server(struct nfs_server *server);
 200 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
 201                                            struct nfs_fh *,
 202                                            struct nfs_fattr *,
 203                                            rpc_authflavor_t);
 204 extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
 205 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
 206 extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 207                                              const struct sockaddr *ds_addr,
 208                                              int ds_addrlen, int ds_proto,
 209                                              unsigned int ds_timeo,
 210                                              unsigned int ds_retrans);
 211 #ifdef CONFIG_PROC_FS
 212 extern int __init nfs_fs_proc_init(void);
 213 extern void nfs_fs_proc_exit(void);
 214 #else
 215 static inline int nfs_fs_proc_init(void)
 216 {
 217         return 0;
 218 }
 219 static inline void nfs_fs_proc_exit(void)
 220 {
 221 }
 222 #endif
 223
 224 #ifdef CONFIG_NFS_V4_1
 225 int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *);
 226 #endif
 227
 228 /* callback_xdr.c */
 229 extern struct svc_version nfs4_callback_version1;
 230 extern struct svc_version nfs4_callback_version4;
 231
 232 struct nfs_pageio_descriptor;
 233 /* pagelist.c */
 234 extern int __init nfs_init_nfspagecache(void);
 235 extern void nfs_destroy_nfspagecache(void);
 236 extern int __init nfs_init_readpagecache(void);
 237 extern void nfs_destroy_readpagecache(void);
 238 extern int __init nfs_init_writepagecache(void);
 239 extern void nfs_destroy_writepagecache(void);
 240
 241 extern int __init nfs_init_directcache(void);
 242 extern void nfs_destroy_directcache(void);
 243 extern bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount);
 244 extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
 245                               struct nfs_pgio_header *hdr,
 246                               void (*release)(struct nfs_pgio_header *hdr));
 247 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
 248
 249 /* nfs2xdr.c */
 250 extern struct rpc_procinfo nfs_procedures[];
 251 extern int nfs2_decode_dirent(struct xdr_stream *,
 252                                 struct nfs_entry *, int);
 253
 254 /* nfs3xdr.c */
 255 extern struct rpc_procinfo nfs3_procedures[];
 256 extern int nfs3_decode_dirent(struct xdr_stream *,
 257                                 struct nfs_entry *, int);
 258
 259 /* nfs4xdr.c */
 260 #ifdef CONFIG_NFS_V4
 261 extern int nfs4_decode_dirent(struct xdr_stream *,
 262                                 struct nfs_entry *, int);
 263 #endif
 264 #ifdef CONFIG_NFS_V4_1
 265 extern const u32 nfs41_maxread_overhead;
 266 extern const u32 nfs41_maxwrite_overhead;
 267 #endif
 268
 269 /* nfs4proc.c */
 270 #ifdef CONFIG_NFS_V4
 271 extern struct rpc_procinfo nfs4_procedures[];
 272 #endif
 273
 274 extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);
 275
 276 /* proc.c */
 277 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
 278 extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
 279                            const struct rpc_timeout *timeparms,
 280                            const char *ip_addr, rpc_authflavor_t authflavour);
 281
 282 /* dir.c */
 283 extern int nfs_access_cache_shrinker(struct shrinker *shrink,
 284                                         struct shrink_control *sc);
 285 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
 286 int nfs_create(struct inode *, struct dentry *, umode_t, bool);
 287 int nfs_mkdir(struct inode *, struct dentry *, umode_t);
 288 int nfs_rmdir(struct inode *, struct dentry *);
 289 int nfs_unlink(struct inode *, struct dentry *);
 290 int nfs_symlink(struct inode *, struct dentry *, const char *);
 291 int nfs_link(struct dentry *, struct inode *, struct dentry *);
 292 int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
 293 int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
 294
 295 /* file.c */
 296 int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int);
 297 loff_t nfs_file_llseek(struct file *, loff_t, int);
 298 int nfs_file_flush(struct file *, fl_owner_t);
 299 ssize_t nfs_file_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
 300 ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
 301                              size_t, unsigned int);
 302 int nfs_file_mmap(struct file *, struct vm_area_struct *);
 303 ssize_t nfs_file_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
 304 int nfs_file_release(struct inode *, struct file *);
 305 int nfs_lock(struct file *, int, struct file_lock *);
 306 int nfs_flock(struct file *, int, struct file_lock *);
 307 ssize_t nfs_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *,
 308                               size_t, unsigned int);
 309 int nfs_check_flags(int);
 310 int nfs_setlease(struct file *, long, struct file_lock **);
 311
 312 /* inode.c */
 313 extern struct workqueue_struct *nfsiod_workqueue;
 314 extern struct inode *nfs_alloc_inode(struct super_block *sb);
 315 extern void nfs_destroy_inode(struct inode *);
 316 extern int nfs_write_inode(struct inode *, struct writeback_control *);
 317 extern void nfs_evict_inode(struct inode *);
 318 #ifdef CONFIG_NFS_V4
 319 extern void nfs4_evict_inode(struct inode *);
 320 #endif
 321 void nfs_zap_acl_cache(struct inode *inode);
 322 extern int nfs_wait_bit_killable(void *word);
 323
 324 /* super.c */
 325 extern struct file_system_type nfs_fs_type;
 326 extern struct file_system_type nfs_xdev_fs_type;
 327 #ifdef CONFIG_NFS_V4
 328 extern struct file_system_type nfs4_xdev_fs_type;
 329 extern struct file_system_type nfs4_referral_fs_type;
 330 #endif
 331 struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
 332                         struct nfs_subversion *);
 333 void nfs_initialise_sb(struct super_block *);
 334 int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
 335 int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
 336 struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
 337                                    struct nfs_mount_info *, struct nfs_subversion *);
 338 struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
 339 struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
 340                 const char *, struct nfs_mount_info *);
 341 void nfs_kill_super(struct super_block *);
 342 void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
 343
 344 extern struct rpc_stat nfs_rpcstat;
 345
 346 extern int __init register_nfs_fs(void);
 347 extern void __exit unregister_nfs_fs(void);
 348 extern void nfs_sb_active(struct super_block *sb);
 349 extern void nfs_sb_deactive(struct super_block *sb);
 350
 351 /* namespace.c */
 352 extern char *nfs_path(char **p, struct dentry *dentry,
 353                       char *buffer, ssize_t buflen);
 354 extern struct vfsmount *nfs_d_automount(struct path *path);
 355 struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
 356                               struct nfs_fh *, struct nfs_fattr *);
 357 struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
 358                                  struct nfs_fattr *, rpc_authflavor_t);
 359
 360 /* getroot.c */
 361 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
 362                                    const char *);
 363 #ifdef CONFIG_NFS_V4
 364 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
 365                                     const char *);
 366
 367 extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh);
 368 #endif
 369
 370 struct nfs_pgio_completion_ops;
 371 /* read.c */
 372 extern struct nfs_read_header *nfs_readhdr_alloc(void);
 373 extern void nfs_readhdr_free(struct nfs_pgio_header *hdr);
 374 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 375                         struct inode *inode,
 376                         const struct nfs_pgio_completion_ops *compl_ops);
 377 extern int nfs_initiate_read(struct rpc_clnt *clnt,
 378                              struct nfs_read_data *data,
 379                              const struct rpc_call_ops *call_ops, int flags);
 380 extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 381 extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
 382                               struct nfs_pgio_header *hdr);
 383 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 384                         struct inode *inode,
 385                         const struct nfs_pgio_completion_ops *compl_ops);
 386 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 387 extern void nfs_readdata_release(struct nfs_read_data *rdata);
 388
 389 /* super.c */
 390 void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
 391 void nfs_umount_begin(struct super_block *);
 392 int  nfs_statfs(struct dentry *, struct kstatfs *);
 393 int  nfs_show_options(struct seq_file *, struct dentry *);
 394 int  nfs_show_devname(struct seq_file *, struct dentry *);
 395 int  nfs_show_path(struct seq_file *, struct dentry *);
 396 int  nfs_show_stats(struct seq_file *, struct dentry *);
 397 void nfs_put_super(struct super_block *);
 398 int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 399
 400 /* write.c */
 401 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
 402                         struct inode *inode, int ioflags,
 403                         const struct nfs_pgio_completion_ops *compl_ops);
 404 extern struct nfs_write_header *nfs_writehdr_alloc(void);
 405 extern void nfs_writehdr_free(struct nfs_pgio_header *hdr);
 406 extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
 407                              struct nfs_pgio_header *hdr);
 408 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
 409                         struct inode *inode, int ioflags,
 410                         const struct nfs_pgio_completion_ops *compl_ops);
 411 extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
 412 extern void nfs_writedata_release(struct nfs_write_data *wdata);
 413 extern void nfs_commit_free(struct nfs_commit_data *p);
 414 extern int nfs_initiate_write(struct rpc_clnt *clnt,
 415                               struct nfs_write_data *data,
 416                               const struct rpc_call_ops *call_ops,
 417                               int how, int flags);
 418 extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
 419 extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
 420 extern int nfs_initiate_commit(struct rpc_clnt *clnt,
 421                                struct nfs_commit_data *data,
 422                                const struct rpc_call_ops *call_ops,
 423                                int how, int flags);
 424 extern void nfs_init_commit(struct nfs_commit_data *data,
 425                             struct list_head *head,
 426                             struct pnfs_layout_segment *lseg,
 427                             struct nfs_commit_info *cinfo);
 428 int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
 429                          struct nfs_commit_info *cinfo, int max);
 430 int nfs_scan_commit(struct inode *inode, struct list_head *dst,
 431                     struct nfs_commit_info *cinfo);
 432 void nfs_mark_request_commit(struct nfs_page *req,
 433                              struct pnfs_layout_segment *lseg,
 434                              struct nfs_commit_info *cinfo);
 435 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
 436                             int how, struct nfs_commit_info *cinfo);
 437 void nfs_retry_commit(struct list_head *page_list,
 438                       struct pnfs_layout_segment *lseg,
 439                       struct nfs_commit_info *cinfo);
 440 void nfs_commitdata_release(struct nfs_commit_data *data);
 441 void nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst,
 442                                  struct nfs_commit_info *cinfo);
 443 void nfs_request_remove_commit_list(struct nfs_page *req,
 444                                     struct nfs_commit_info *cinfo);
 445 void nfs_init_cinfo(struct nfs_commit_info *cinfo,
 446                     struct inode *inode,
 447                     struct nfs_direct_req *dreq);
 448
 449 #ifdef CONFIG_MIGRATION
 450 extern int nfs_migrate_page(struct address_space *,
 451                 struct page *, struct page *, enum migrate_mode);
 452 #else
 453 #define nfs_migrate_page NULL
 454 #endif
 455
 456 /* direct.c */
 457 void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
 458                               struct nfs_direct_req *dreq);
 459 static inline void nfs_inode_dio_wait(struct inode *inode)
 460 {
 461         inode_dio_wait(inode);
 462 }
 463
 464 /* nfs4proc.c */
 465 extern void __nfs4_read_done_cb(struct nfs_read_data *);
 466 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 467                             const struct rpc_timeout *timeparms,
 468                             const char *ip_addr,
 469                             rpc_authflavor_t authflavour);
 470 extern int _nfs4_call_sync(struct rpc_clnt *clnt,
 471                            struct nfs_server *server,
 472                            struct rpc_message *msg,
 473                            struct nfs4_sequence_args *args,
 474                            struct nfs4_sequence_res *res,
 475                            int cache_reply);
 476 extern int _nfs4_call_sync_session(struct rpc_clnt *clnt,
 477                                    struct nfs_server *server,
 478                                    struct rpc_message *msg,
 479                                    struct nfs4_sequence_args *args,
 480                                    struct nfs4_sequence_res *res,
 481                                    int cache_reply);
 482
 483 /*
 484  * Determine the device name as a string
 485  */
 486 static inline char *nfs_devname(struct dentry *dentry,
 487                                 char *buffer, ssize_t buflen)
 488 {
 489         char *dummy;
 490         return nfs_path(&dummy, dentry, buffer, buflen);
 491 }
 492
 493 /*
 494  * Determine the actual block size (and log2 thereof)
 495  */
 496 static inline
 497 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
 498 {
 499         /* make sure blocksize is a power of two */
 500         if ((bsize & (bsize - 1)) || nrbitsp) {
 501                 unsigned char   nrbits;
 502
 503                 for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
 504                         ;
 505                 bsize = 1 << nrbits;
 506                 if (nrbitsp)
 507                         *nrbitsp = nrbits;
 508         }
 509
 510         return bsize;
 511 }
 512
 513 /*
 514  * Calculate the number of 512byte blocks used.
 515  */
 516 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
 517 {
 518         blkcnt_t used = (tsize + 511) >> 9;
 519         return (used > ULONG_MAX) ? ULONG_MAX : used;
 520 }
 521
 522 /*
 523  * Compute and set NFS server blocksize
 524  */
 525 static inline
 526 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
 527 {
 528         if (bsize < NFS_MIN_FILE_IO_SIZE)
 529                 bsize = NFS_DEF_FILE_IO_SIZE;
 530         else if (bsize >= NFS_MAX_FILE_IO_SIZE)
 531                 bsize = NFS_MAX_FILE_IO_SIZE;
 532
 533         return nfs_block_bits(bsize, nrbitsp);
 534 }
 535
 536 /*
 537  * Determine the maximum file size for a superblock
 538  */
 539 static inline
 540 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 541 {
 542         sb->s_maxbytes = (loff_t)maxfilesize;
 543         if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
 544                 sb->s_maxbytes = MAX_LFS_FILESIZE;
 545 }
 546
 547 /*
 548  * Determine the number of bytes of data the page contains
 549  */
 550 static inline
 551 unsigned int nfs_page_length(struct page *page)
 552 {
 553         loff_t i_size = i_size_read(page->mapping->host);
 554
 555         if (i_size > 0) {
 556                 pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 557                 if (page->index < end_index)
 558                         return PAGE_CACHE_SIZE;
 559                 if (page->index == end_index)
 560                         return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
 561         }
 562         return 0;
 563 }
 564
 565 /*
 566  * Convert a umode to a dirent->d_type
 567  */
 568 static inline
 569 unsigned char nfs_umode_to_dtype(umode_t mode)
 570 {
 571         return (mode >> 12) & 15;
 572 }
 573
 574 /*
 575  * Determine the number of pages in an array of length 'len' and
 576  * with a base offset of 'base'
 577  */
 578 static inline
 579 unsigned int nfs_page_array_len(unsigned int base, size_t len)
 580 {
 581         return ((unsigned long)len + (unsigned long)base +
 582                 PAGE_SIZE - 1) >> PAGE_SHIFT;
 583 }
 584
 585 /*
 586  * Convert a struct timespec into a 64-bit change attribute
 587  *
 588  * This does approximately the same thing as timespec_to_ns(),
 589  * but for calculation efficiency, we multiply the seconds by
 590  * 1024*1024*1024.
 591  */
 592 static inline
 593 u64 nfs_timespec_to_change_attr(const struct timespec *ts)
 594 {
 595         return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
 596 }