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 #include <linux/crc32.h>
   9
  10 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
  11
  12 struct nfs_string;
  13
  14 /* Maximum number of readahead requests
  15  * FIXME: this should really be a sysctl so that users may tune it to suit
  16  *        their needs. People that do NFS over a slow network, might for
  17  *        instance want to reduce it to something closer to 1 for improved
  18  *        interactive response.
  19  */
  20 #define NFS_MAX_READAHEAD       (RPC_DEF_SLOT_TABLE - 1)
  21
  22 static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
  23 {
  24         if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
  25                 fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
  26 }
  27
  28 static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
  29 {
  30         if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
  31             (((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
  32              ((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
  33                 return 0;
  34
  35         fattr->fileid = fattr->mounted_on_fileid;
  36         return 1;
  37 }
  38
  39 struct nfs_clone_mount {
  40         const struct super_block *sb;
  41         const struct dentry *dentry;
  42         struct nfs_fh *fh;
  43         struct nfs_fattr *fattr;
  44         char *hostname;
  45         char *mnt_path;
  46         struct sockaddr *addr;
  47         size_t addrlen;
  48         rpc_authflavor_t authflavor;
  49 };
  50
  51 /*
  52  * Note: RFC 1813 doesn't limit the number of auth flavors that
  53  * a server can return, so make something up.
  54  */
  55 #define NFS_MAX_SECFLAVORS      (12)
  56
  57 /*
  58  * Value used if the user did not specify a port value.
  59  */
  60 #define NFS_UNSPEC_PORT         (-1)
  61
  62 /*
  63  * Maximum number of pages that readdir can use for creating
  64  * a vmapped array of pages.
  65  */
  66 #define NFS_MAX_READDIR_PAGES 8
  67
  68 struct nfs_client_initdata {
  69         unsigned long init_flags;
  70         const char *hostname;
  71         const struct sockaddr *addr;
  72         size_t addrlen;
  73         struct nfs_subversion *nfs_mod;
  74         int proto;
  75         u32 minorversion;
  76         struct net *net;
  77 };
  78
  79 /*
  80  * In-kernel mount arguments
  81  */
  82 struct nfs_parsed_mount_data {
  83         int                     flags;
  84         unsigned int            rsize, wsize;
  85         unsigned int            timeo, retrans;
  86         unsigned int            acregmin, acregmax,
  87                                 acdirmin, acdirmax;
  88         unsigned int            namlen;
  89         unsigned int            options;
  90         unsigned int            bsize;
  91         struct nfs_auth_info    auth_info;
  92         rpc_authflavor_t        selected_flavor;
  93         char                    *client_address;
  94         unsigned int            version;
  95         unsigned int            minorversion;
  96         char                    *fscache_uniq;
  97         bool                    need_mount;
  98
  99         struct {
 100                 struct sockaddr_storage address;
 101                 size_t                  addrlen;
 102                 char                    *hostname;
 103                 u32                     version;
 104                 int                     port;
 105                 unsigned short          protocol;
 106         } mount_server;
 107
 108         struct {
 109                 struct sockaddr_storage address;
 110                 size_t                  addrlen;
 111                 char                    *hostname;
 112                 char                    *export_path;
 113                 int                     port;
 114                 unsigned short          protocol;
 115         } nfs_server;
 116
 117         struct security_mnt_opts lsm_opts;
 118         struct net              *net;
 119 };
 120
 121 /* mount_clnt.c */
 122 struct nfs_mount_request {
 123         struct sockaddr         *sap;
 124         size_t                  salen;
 125         char                    *hostname;
 126         char                    *dirpath;
 127         u32                     version;
 128         unsigned short          protocol;
 129         struct nfs_fh           *fh;
 130         int                     noresvport;
 131         unsigned int            *auth_flav_len;
 132         rpc_authflavor_t        *auth_flavs;
 133         struct net              *net;
 134 };
 135
 136 struct nfs_mount_info {
 137         void (*fill_super)(struct super_block *, struct nfs_mount_info *);
 138         int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
 139         struct nfs_parsed_mount_data *parsed;
 140         struct nfs_clone_mount *cloned;
 141         struct nfs_fh *mntfh;
 142 };
 143
 144 extern int nfs_mount(struct nfs_mount_request *info);
 145 extern void nfs_umount(const struct nfs_mount_request *info);
 146
 147 /* client.c */
 148 extern const struct rpc_program nfs_program;
 149 extern void nfs_clients_init(struct net *net);
 150 extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
 151 int nfs_create_rpc_client(struct nfs_client *, const struct rpc_timeout *, rpc_authflavor_t);
 152 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
 153                                   const struct rpc_timeout *, const char *,
 154                                   rpc_authflavor_t);
 155 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
 156 void nfs_server_insert_lists(struct nfs_server *);
 157 void nfs_server_remove_lists(struct nfs_server *);
 158 void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
 159 int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
 160                 rpc_authflavor_t);
 161 struct nfs_server *nfs_alloc_server(void);
 162 void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
 163
 164 extern void nfs_cleanup_cb_ident_idr(struct net *);
 165 extern void nfs_put_client(struct nfs_client *);
 166 extern void nfs_free_client(struct nfs_client *);
 167 extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
 168 extern struct nfs_client *
 169 nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
 170                                 struct nfs4_sessionid *, u32);
 171 extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
 172                                         struct nfs_subversion *);
 173 extern struct nfs_server *nfs4_create_server(
 174                                         struct nfs_mount_info *,
 175                                         struct nfs_subversion *);
 176 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
 177                                                       struct nfs_fh *);
 178 extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
 179                                         struct sockaddr *sap, size_t salen,
 180                                         struct net *net);
 181 extern void nfs_free_server(struct nfs_server *server);
 182 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
 183                                            struct nfs_fh *,
 184                                            struct nfs_fattr *,
 185                                            rpc_authflavor_t);
 186 extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
 187 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
 188 extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 189                                              const struct sockaddr *ds_addr,
 190                                              int ds_addrlen, int ds_proto,
 191                                              unsigned int ds_timeo,
 192                                              unsigned int ds_retrans);
 193 extern struct rpc_clnt *nfs4_find_or_create_ds_client(struct nfs_client *,
 194                                                 struct inode *);
 195 #ifdef CONFIG_PROC_FS
 196 extern int __init nfs_fs_proc_init(void);
 197 extern void nfs_fs_proc_exit(void);
 198 extern int nfs_fs_proc_net_init(struct net *net);
 199 extern void nfs_fs_proc_net_exit(struct net *net);
 200 #else
 201 static inline int nfs_fs_proc_net_init(struct net *net)
 202 {
 203         return 0;
 204 }
 205 static inline void nfs_fs_proc_net_exit(struct net *net)
 206 {
 207 }
 208 static inline int nfs_fs_proc_init(void)
 209 {
 210         return 0;
 211 }
 212 static inline void nfs_fs_proc_exit(void)
 213 {
 214 }
 215 #endif
 216
 217 #ifdef CONFIG_NFS_V4_1
 218 int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *);
 219 #endif
 220
 221 /* callback_xdr.c */
 222 extern struct svc_version nfs4_callback_version1;
 223 extern struct svc_version nfs4_callback_version4;
 224
 225 struct nfs_pageio_descriptor;
 226 /* pagelist.c */
 227 extern int __init nfs_init_nfspagecache(void);
 228 extern void nfs_destroy_nfspagecache(void);
 229 extern int __init nfs_init_readpagecache(void);
 230 extern void nfs_destroy_readpagecache(void);
 231 extern int __init nfs_init_writepagecache(void);
 232 extern void nfs_destroy_writepagecache(void);
 233
 234 extern int __init nfs_init_directcache(void);
 235 extern void nfs_destroy_directcache(void);
 236 extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
 237                               struct nfs_pgio_header *hdr,
 238                               void (*release)(struct nfs_pgio_header *hdr));
 239 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
 240 int nfs_iocounter_wait(struct nfs_io_counter *c);
 241
 242 extern const struct nfs_pageio_ops nfs_pgio_rw_ops;
 243 struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *);
 244 void nfs_pgio_header_free(struct nfs_pgio_header *);
 245 void nfs_pgio_data_destroy(struct nfs_pgio_header *);
 246 int nfs_generic_pgio(struct nfs_pageio_descriptor *, struct nfs_pgio_header *);
 247 int nfs_initiate_pgio(struct rpc_clnt *, struct nfs_pgio_header *,
 248                       const struct rpc_call_ops *, int, int);
 249 void nfs_free_request(struct nfs_page *req);
 250
 251 static inline void nfs_iocounter_init(struct nfs_io_counter *c)
 252 {
 253         c->flags = 0;
 254         atomic_set(&c->io_count, 0);
 255 }
 256
 257 /* nfs2xdr.c */
 258 extern struct rpc_procinfo nfs_procedures[];
 259 extern int nfs2_decode_dirent(struct xdr_stream *,
 260                                 struct nfs_entry *, int);
 261
 262 /* nfs3xdr.c */
 263 extern struct rpc_procinfo nfs3_procedures[];
 264 extern int nfs3_decode_dirent(struct xdr_stream *,
 265                                 struct nfs_entry *, int);
 266
 267 /* nfs4xdr.c */
 268 #if IS_ENABLED(CONFIG_NFS_V4)
 269 extern int nfs4_decode_dirent(struct xdr_stream *,
 270                                 struct nfs_entry *, int);
 271 #endif
 272 #ifdef CONFIG_NFS_V4_1
 273 extern const u32 nfs41_maxread_overhead;
 274 extern const u32 nfs41_maxwrite_overhead;
 275 extern const u32 nfs41_maxgetdevinfo_overhead;
 276 #endif
 277
 278 /* nfs4proc.c */
 279 #if IS_ENABLED(CONFIG_NFS_V4)
 280 extern struct rpc_procinfo nfs4_procedures[];
 281 #endif
 282
 283 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
 284 extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
 285 static inline void nfs4_label_free(struct nfs4_label *label)
 286 {
 287         if (label) {
 288                 kfree(label->label);
 289                 kfree(label);
 290         }
 291         return;
 292 }
 293
 294 static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
 295 {
 296         if (nfs_server_capable(&nfsi->vfs_inode, NFS_CAP_SECURITY_LABEL))
 297                 nfsi->cache_validity |= NFS_INO_INVALID_LABEL;
 298 }
 299 #else
 300 static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
 301 static inline void nfs4_label_free(void *label) {}
 302 static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
 303 {
 304 }
 305 #endif /* CONFIG_NFS_V4_SECURITY_LABEL */
 306
 307 /* proc.c */
 308 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
 309 extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
 310                            const struct rpc_timeout *timeparms,
 311                            const char *ip_addr);
 312
 313 /* dir.c */
 314 extern void nfs_force_use_readdirplus(struct inode *dir);
 315 extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
 316                                             struct shrink_control *sc);
 317 extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
 318                                            struct shrink_control *sc);
 319 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
 320 int nfs_create(struct inode *, struct dentry *, umode_t, bool);
 321 int nfs_mkdir(struct inode *, struct dentry *, umode_t);
 322 int nfs_rmdir(struct inode *, struct dentry *);
 323 int nfs_unlink(struct inode *, struct dentry *);
 324 int nfs_symlink(struct inode *, struct dentry *, const char *);
 325 int nfs_link(struct dentry *, struct inode *, struct dentry *);
 326 int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
 327 int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
 328
 329 /* file.c */
 330 int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int);
 331 loff_t nfs_file_llseek(struct file *, loff_t, int);
 332 int nfs_file_flush(struct file *, fl_owner_t);
 333 ssize_t nfs_file_read(struct kiocb *, struct iov_iter *);
 334 ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
 335                              size_t, unsigned int);
 336 int nfs_file_mmap(struct file *, struct vm_area_struct *);
 337 ssize_t nfs_file_write(struct kiocb *, struct iov_iter *);
 338 int nfs_file_release(struct inode *, struct file *);
 339 int nfs_lock(struct file *, int, struct file_lock *);
 340 int nfs_flock(struct file *, int, struct file_lock *);
 341 int nfs_check_flags(int);
 342
 343 /* inode.c */
 344 extern struct workqueue_struct *nfsiod_workqueue;
 345 extern struct inode *nfs_alloc_inode(struct super_block *sb);
 346 extern void nfs_destroy_inode(struct inode *);
 347 extern int nfs_write_inode(struct inode *, struct writeback_control *);
 348 extern int nfs_drop_inode(struct inode *);
 349 extern void nfs_clear_inode(struct inode *);
 350 extern void nfs_evict_inode(struct inode *);
 351 void nfs_zap_acl_cache(struct inode *inode);
 352 extern int nfs_wait_bit_killable(struct wait_bit_key *key);
 353
 354 /* super.c */
 355 extern const struct super_operations nfs_sops;
 356 extern struct file_system_type nfs_fs_type;
 357 extern struct file_system_type nfs_xdev_fs_type;
 358 #if IS_ENABLED(CONFIG_NFS_V4)
 359 extern struct file_system_type nfs4_xdev_fs_type;
 360 extern struct file_system_type nfs4_referral_fs_type;
 361 #endif
 362 bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
 363 struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
 364                         struct nfs_subversion *);
 365 void nfs_initialise_sb(struct super_block *);
 366 int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
 367 int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
 368 struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
 369                                    struct nfs_mount_info *, struct nfs_subversion *);
 370 struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
 371 struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
 372                 const char *, struct nfs_mount_info *);
 373 void nfs_kill_super(struct super_block *);
 374 void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
 375
 376 extern struct rpc_stat nfs_rpcstat;
 377
 378 extern int __init register_nfs_fs(void);
 379 extern void __exit unregister_nfs_fs(void);
 380 extern void nfs_sb_active(struct super_block *sb);
 381 extern void nfs_sb_deactive(struct super_block *sb);
 382
 383 /* namespace.c */
 384 #define NFS_PATH_CANONICAL 1
 385 extern char *nfs_path(char **p, struct dentry *dentry,
 386                       char *buffer, ssize_t buflen, unsigned flags);
 387 extern struct vfsmount *nfs_d_automount(struct path *path);
 388 struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
 389                               struct nfs_fh *, struct nfs_fattr *);
 390 struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
 391                                  struct nfs_fattr *, rpc_authflavor_t);
 392
 393 /* getroot.c */
 394 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
 395                                    const char *);
 396 #if IS_ENABLED(CONFIG_NFS_V4)
 397 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
 398                                     const char *);
 399
 400 extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool);
 401 #endif
 402
 403 struct nfs_pgio_completion_ops;
 404 /* read.c */
 405 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 406                         struct inode *inode, bool force_mds,
 407                         const struct nfs_pgio_completion_ops *compl_ops);
 408 extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 409 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 410
 411 /* super.c */
 412 void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
 413 void nfs_umount_begin(struct super_block *);
 414 int  nfs_statfs(struct dentry *, struct kstatfs *);
 415 int  nfs_show_options(struct seq_file *, struct dentry *);
 416 int  nfs_show_devname(struct seq_file *, struct dentry *);
 417 int  nfs_show_path(struct seq_file *, struct dentry *);
 418 int  nfs_show_stats(struct seq_file *, struct dentry *);
 419 void nfs_put_super(struct super_block *);
 420 int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 421
 422 /* write.c */
 423 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
 424                         struct inode *inode, int ioflags, bool force_mds,
 425                         const struct nfs_pgio_completion_ops *compl_ops);
 426 extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
 427 extern void nfs_commit_free(struct nfs_commit_data *p);
 428 extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
 429 extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
 430 extern int nfs_initiate_commit(struct rpc_clnt *clnt,
 431                                struct nfs_commit_data *data,
 432                                const struct rpc_call_ops *call_ops,
 433                                int how, int flags);
 434 extern void nfs_init_commit(struct nfs_commit_data *data,
 435                             struct list_head *head,
 436                             struct pnfs_layout_segment *lseg,
 437                             struct nfs_commit_info *cinfo);
 438 int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
 439                          struct nfs_commit_info *cinfo, int max);
 440 unsigned long nfs_reqs_to_commit(struct nfs_commit_info *);
 441 int nfs_scan_commit(struct inode *inode, struct list_head *dst,
 442                     struct nfs_commit_info *cinfo);
 443 void nfs_mark_request_commit(struct nfs_page *req,
 444                              struct pnfs_layout_segment *lseg,
 445                              struct nfs_commit_info *cinfo);
 446 int nfs_write_need_commit(struct nfs_pgio_header *);
 447 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
 448                             int how, struct nfs_commit_info *cinfo);
 449 void nfs_retry_commit(struct list_head *page_list,
 450                       struct pnfs_layout_segment *lseg,
 451                       struct nfs_commit_info *cinfo);
 452 void nfs_commitdata_release(struct nfs_commit_data *data);
 453 void nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst,
 454                                  struct nfs_commit_info *cinfo);
 455 void nfs_request_remove_commit_list(struct nfs_page *req,
 456                                     struct nfs_commit_info *cinfo);
 457 void nfs_init_cinfo(struct nfs_commit_info *cinfo,
 458                     struct inode *inode,
 459                     struct nfs_direct_req *dreq);
 460 int nfs_key_timeout_notify(struct file *filp, struct inode *inode);
 461 bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx);
 462
 463 #ifdef CONFIG_MIGRATION
 464 extern int nfs_migrate_page(struct address_space *,
 465                 struct page *, struct page *, enum migrate_mode);
 466 #else
 467 #define nfs_migrate_page NULL
 468 #endif
 469
 470 /* unlink.c */
 471 extern struct rpc_task *
 472 nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
 473                  struct dentry *old_dentry, struct dentry *new_dentry,
 474                  void (*complete)(struct rpc_task *, struct nfs_renamedata *));
 475 extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
 476
 477 /* direct.c */
 478 void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
 479                               struct nfs_direct_req *dreq);
 480 static inline void nfs_inode_dio_wait(struct inode *inode)
 481 {
 482         inode_dio_wait(inode);
 483 }
 484 extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);
 485
 486 /* nfs4proc.c */
 487 extern void __nfs4_read_done_cb(struct nfs_pgio_header *);
 488 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 489                             const struct rpc_timeout *timeparms,
 490                             const char *ip_addr);
 491 extern int nfs40_walk_client_list(struct nfs_client *clp,
 492                                 struct nfs_client **result,
 493                                 struct rpc_cred *cred);
 494 extern int nfs41_walk_client_list(struct nfs_client *clp,
 495                                 struct nfs_client **result,
 496                                 struct rpc_cred *cred);
 497
 498 /*
 499  * Determine the device name as a string
 500  */
 501 static inline char *nfs_devname(struct dentry *dentry,
 502                                 char *buffer, ssize_t buflen)
 503 {
 504         char *dummy;
 505         return nfs_path(&dummy, dentry, buffer, buflen, NFS_PATH_CANONICAL);
 506 }
 507
 508 /*
 509  * Determine the actual block size (and log2 thereof)
 510  */
 511 static inline
 512 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
 513 {
 514         /* make sure blocksize is a power of two */
 515         if ((bsize & (bsize - 1)) || nrbitsp) {
 516                 unsigned char   nrbits;
 517
 518                 for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
 519                         ;
 520                 bsize = 1 << nrbits;
 521                 if (nrbitsp)
 522                         *nrbitsp = nrbits;
 523         }
 524
 525         return bsize;
 526 }
 527
 528 /*
 529  * Calculate the number of 512byte blocks used.
 530  */
 531 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
 532 {
 533         blkcnt_t used = (tsize + 511) >> 9;
 534         return (used > ULONG_MAX) ? ULONG_MAX : used;
 535 }
 536
 537 /*
 538  * Compute and set NFS server blocksize
 539  */
 540 static inline
 541 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
 542 {
 543         if (bsize < NFS_MIN_FILE_IO_SIZE)
 544                 bsize = NFS_DEF_FILE_IO_SIZE;
 545         else if (bsize >= NFS_MAX_FILE_IO_SIZE)
 546                 bsize = NFS_MAX_FILE_IO_SIZE;
 547
 548         return nfs_block_bits(bsize, nrbitsp);
 549 }
 550
 551 /*
 552  * Determine the maximum file size for a superblock
 553  */
 554 static inline
 555 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
 556 {
 557         sb->s_maxbytes = (loff_t)maxfilesize;
 558         if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
 559                 sb->s_maxbytes = MAX_LFS_FILESIZE;
 560 }
 561
 562 /*
 563  * Determine the number of bytes of data the page contains
 564  */
 565 static inline
 566 unsigned int nfs_page_length(struct page *page)
 567 {
 568         loff_t i_size = i_size_read(page_file_mapping(page)->host);
 569
 570         if (i_size > 0) {
 571                 pgoff_t page_index = page_file_index(page);
 572                 pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
 573                 if (page_index < end_index)
 574                         return PAGE_CACHE_SIZE;
 575                 if (page_index == end_index)
 576                         return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1;
 577         }
 578         return 0;
 579 }
 580
 581 /*
 582  * Convert a umode to a dirent->d_type
 583  */
 584 static inline
 585 unsigned char nfs_umode_to_dtype(umode_t mode)
 586 {
 587         return (mode >> 12) & 15;
 588 }
 589
 590 /*
 591  * Determine the number of pages in an array of length 'len' and
 592  * with a base offset of 'base'
 593  */
 594 static inline
 595 unsigned int nfs_page_array_len(unsigned int base, size_t len)
 596 {
 597         return ((unsigned long)len + (unsigned long)base +
 598                 PAGE_SIZE - 1) >> PAGE_SHIFT;
 599 }
 600
 601 /*
 602  * Convert a struct timespec into a 64-bit change attribute
 603  *
 604  * This does approximately the same thing as timespec_to_ns(),
 605  * but for calculation efficiency, we multiply the seconds by
 606  * 1024*1024*1024.
 607  */
 608 static inline
 609 u64 nfs_timespec_to_change_attr(const struct timespec *ts)
 610 {
 611         return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
 612 }
 613
 614 #ifdef CONFIG_CRC32
 615 /**
 616  * nfs_fhandle_hash - calculate the crc32 hash for the filehandle
 617  * @fh - pointer to filehandle
 618  *
 619  * returns a crc32 hash for the filehandle that is compatible with
 620  * the one displayed by "wireshark".
 621  */
 622 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
 623 {
 624         return ~crc32_le(0xFFFFFFFF, &fh->data[0], fh->size);
 625 }
 626 #else
 627 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
 628 {
 629         return 0;
 630 }
 631 #endif