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 unsigned int rsize, wsize; 105 unsigned int timeo, retrans; 106 unsigned int acregmin, acregmax, 107 acdirmin, acdirmax; 108 unsigned 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(struct nfs_mount_info *, 191 struct nfs_subversion *); 192 extern struct nfs_server *nfs4_create_server( 193 struct nfs_mount_info *, 194 struct nfs_subversion *); 195 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *, 196 struct nfs_fh *); 197 extern void nfs_free_server(struct nfs_server *server); 198 extern struct nfs_server *nfs_clone_server(struct nfs_server *, 199 struct nfs_fh *, 200 struct nfs_fattr *, 201 rpc_authflavor_t); 202 extern int nfs_wait_client_init_complete(const struct nfs_client *clp); 203 extern void nfs_mark_client_ready(struct nfs_client *clp, int state); 204 extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp, 205 const struct sockaddr *ds_addr, 206 int ds_addrlen, int ds_proto, 207 unsigned int ds_timeo, 208 unsigned int ds_retrans); 209 #ifdef CONFIG_PROC_FS 210 extern int __init nfs_fs_proc_init(void); 211 extern void nfs_fs_proc_exit(void); 212 #else 213 static inline int nfs_fs_proc_init(void) 214 { 215 return 0; 216 } 217 static inline void nfs_fs_proc_exit(void) 218 { 219 } 220 #endif 221 222 #ifdef CONFIG_NFS_V4_1 223 int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *); 224 #endif 225 226 /* nfs3client.c */ 227 #if IS_ENABLED(CONFIG_NFS_V3) 228 struct nfs_server *nfs3_create_server(struct nfs_mount_info *, struct nfs_subversion *); 229 struct nfs_server *nfs3_clone_server(struct nfs_server *, struct nfs_fh *, 230 struct nfs_fattr *, rpc_authflavor_t); 231 #endif 232 233 /* callback_xdr.c */ 234 extern struct svc_version nfs4_callback_version1; 235 extern struct svc_version nfs4_callback_version4; 236 237 struct nfs_pageio_descriptor; 238 /* pagelist.c */ 239 extern int __init nfs_init_nfspagecache(void); 240 extern void nfs_destroy_nfspagecache(void); 241 extern int __init nfs_init_readpagecache(void); 242 extern void nfs_destroy_readpagecache(void); 243 extern int __init nfs_init_writepagecache(void); 244 extern void nfs_destroy_writepagecache(void); 245 246 extern int __init nfs_init_directcache(void); 247 extern void nfs_destroy_directcache(void); 248 extern bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount); 249 extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc, 250 struct nfs_pgio_header *hdr, 251 void (*release)(struct nfs_pgio_header *hdr)); 252 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos); 253 254 /* nfs2xdr.c */ 255 extern struct rpc_procinfo nfs_procedures[]; 256 extern int nfs2_decode_dirent(struct xdr_stream *, 257 struct nfs_entry *, int); 258 259 /* nfs3xdr.c */ 260 extern struct rpc_procinfo nfs3_procedures[]; 261 extern int nfs3_decode_dirent(struct xdr_stream *, 262 struct nfs_entry *, int); 263 264 /* nfs4xdr.c */ 265 #if IS_ENABLED(CONFIG_NFS_V4) 266 extern int nfs4_decode_dirent(struct xdr_stream *, 267 struct nfs_entry *, int); 268 #endif 269 #ifdef CONFIG_NFS_V4_1 270 extern const u32 nfs41_maxread_overhead; 271 extern const u32 nfs41_maxwrite_overhead; 272 #endif 273 274 /* nfs4proc.c */ 275 #if IS_ENABLED(CONFIG_NFS_V4) 276 extern struct rpc_procinfo nfs4_procedures[]; 277 #endif 278 279 extern int nfs4_init_ds_session(struct nfs_client *, unsigned long); 280 281 /* proc.c */ 282 void nfs_close_context(struct nfs_open_context *ctx, int is_sync); 283 extern struct nfs_client *nfs_init_client(struct nfs_client *clp, 284 const struct rpc_timeout *timeparms, 285 const char *ip_addr, rpc_authflavor_t authflavour); 286 287 /* dir.c */ 288 extern int nfs_access_cache_shrinker(struct shrinker *shrink, 289 struct shrink_control *sc); 290 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int); 291 int nfs_create(struct inode *, struct dentry *, umode_t, bool); 292 int nfs_mkdir(struct inode *, struct dentry *, umode_t); 293 int nfs_rmdir(struct inode *, struct dentry *); 294 int nfs_unlink(struct inode *, struct dentry *); 295 int nfs_symlink(struct inode *, struct dentry *, const char *); 296 int nfs_link(struct dentry *, struct inode *, struct dentry *); 297 int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t); 298 int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 299 300 /* file.c */ 301 int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int); 302 loff_t nfs_file_llseek(struct file *, loff_t, int); 303 int nfs_file_flush(struct file *, fl_owner_t); 304 ssize_t nfs_file_read(struct kiocb *, const struct iovec *, unsigned long, loff_t); 305 ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *, 306 size_t, unsigned int); 307 int nfs_file_mmap(struct file *, struct vm_area_struct *); 308 ssize_t nfs_file_write(struct kiocb *, const struct iovec *, unsigned long, loff_t); 309 int nfs_file_release(struct inode *, struct file *); 310 int nfs_lock(struct file *, int, struct file_lock *); 311 int nfs_flock(struct file *, int, struct file_lock *); 312 ssize_t nfs_file_splice_write(struct pipe_inode_info *, struct file *, loff_t *, 313 size_t, unsigned int); 314 int nfs_check_flags(int); 315 int nfs_setlease(struct file *, long, struct file_lock **); 316 317 /* inode.c */ 318 extern struct workqueue_struct *nfsiod_workqueue; 319 extern struct inode *nfs_alloc_inode(struct super_block *sb); 320 extern void nfs_destroy_inode(struct inode *); 321 extern int nfs_write_inode(struct inode *, struct writeback_control *); 322 extern void nfs_clear_inode(struct inode *); 323 extern void nfs_evict_inode(struct inode *); 324 void nfs_zap_acl_cache(struct inode *inode); 325 extern int nfs_wait_bit_killable(void *word); 326 327 /* super.c */ 328 extern const struct super_operations nfs_sops; 329 extern struct file_system_type nfs_fs_type; 330 extern struct file_system_type nfs_xdev_fs_type; 331 #if IS_ENABLED(CONFIG_NFS_V4) 332 extern struct file_system_type nfs4_xdev_fs_type; 333 extern struct file_system_type nfs4_referral_fs_type; 334 #endif 335 struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *, 336 struct nfs_subversion *); 337 void nfs_initialise_sb(struct super_block *); 338 int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *); 339 int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *); 340 struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *, 341 struct nfs_mount_info *, struct nfs_subversion *); 342 struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *); 343 struct dentry * nfs_xdev_mount_common(struct file_system_type *, int, 344 const char *, struct nfs_mount_info *); 345 void nfs_kill_super(struct super_block *); 346 void nfs_fill_super(struct super_block *, struct nfs_mount_info *); 347 348 extern struct rpc_stat nfs_rpcstat; 349 350 extern int __init register_nfs_fs(void); 351 extern void __exit unregister_nfs_fs(void); 352 extern void nfs_sb_active(struct super_block *sb); 353 extern void nfs_sb_deactive(struct super_block *sb); 354 extern void nfs_sb_deactive_async(struct super_block *sb); 355 356 /* namespace.c */ 357 #define NFS_PATH_CANONICAL 1 358 extern char *nfs_path(char **p, struct dentry *dentry, 359 char *buffer, ssize_t buflen, unsigned flags); 360 extern struct vfsmount *nfs_d_automount(struct path *path); 361 struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *, 362 struct nfs_fh *, struct nfs_fattr *); 363 struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *, 364 struct nfs_fattr *, rpc_authflavor_t); 365 366 /* getroot.c */ 367 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *, 368 const char *); 369 #if IS_ENABLED(CONFIG_NFS_V4) 370 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *, 371 const char *); 372 373 extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh); 374 #endif 375 376 struct nfs_pgio_completion_ops; 377 /* read.c */ 378 extern struct nfs_read_header *nfs_readhdr_alloc(void); 379 extern void nfs_readhdr_free(struct nfs_pgio_header *hdr); 380 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, 381 struct inode *inode, 382 const struct nfs_pgio_completion_ops *compl_ops); 383 extern int nfs_initiate_read(struct rpc_clnt *clnt, 384 struct nfs_read_data *data, 385 const struct rpc_call_ops *call_ops, int flags); 386 extern void nfs_read_prepare(struct rpc_task *task, void *calldata); 387 extern int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, 388 struct nfs_pgio_header *hdr); 389 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, 390 struct inode *inode, 391 const struct nfs_pgio_completion_ops *compl_ops); 392 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio); 393 extern void nfs_readdata_release(struct nfs_read_data *rdata); 394 395 /* super.c */ 396 void nfs_clone_super(struct super_block *, struct nfs_mount_info *); 397 void nfs_umount_begin(struct super_block *); 398 int nfs_statfs(struct dentry *, struct kstatfs *); 399 int nfs_show_options(struct seq_file *, struct dentry *); 400 int nfs_show_devname(struct seq_file *, struct dentry *); 401 int nfs_show_path(struct seq_file *, struct dentry *); 402 int nfs_show_stats(struct seq_file *, struct dentry *); 403 void nfs_put_super(struct super_block *); 404 int nfs_remount(struct super_block *sb, int *flags, char *raw_data); 405 406 /* write.c */ 407 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, 408 struct inode *inode, int ioflags, 409 const struct nfs_pgio_completion_ops *compl_ops); 410 extern struct nfs_write_header *nfs_writehdr_alloc(void); 411 extern void nfs_writehdr_free(struct nfs_pgio_header *hdr); 412 extern int nfs_generic_flush(struct nfs_pageio_descriptor *desc, 413 struct nfs_pgio_header *hdr); 414 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, 415 struct inode *inode, int ioflags, 416 const struct nfs_pgio_completion_ops *compl_ops); 417 extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio); 418 extern void nfs_writedata_release(struct nfs_write_data *wdata); 419 extern void nfs_commit_free(struct nfs_commit_data *p); 420 extern int nfs_initiate_write(struct rpc_clnt *clnt, 421 struct nfs_write_data *data, 422 const struct rpc_call_ops *call_ops, 423 int how, int flags); 424 extern void nfs_write_prepare(struct rpc_task *task, void *calldata); 425 extern void nfs_commit_prepare(struct rpc_task *task, void *calldata); 426 extern int nfs_initiate_commit(struct rpc_clnt *clnt, 427 struct nfs_commit_data *data, 428 const struct rpc_call_ops *call_ops, 429 int how, int flags); 430 extern void nfs_init_commit(struct nfs_commit_data *data, 431 struct list_head *head, 432 struct pnfs_layout_segment *lseg, 433 struct nfs_commit_info *cinfo); 434 int nfs_scan_commit_list(struct list_head *src, struct list_head *dst, 435 struct nfs_commit_info *cinfo, int max); 436 int nfs_scan_commit(struct inode *inode, struct list_head *dst, 437 struct nfs_commit_info *cinfo); 438 void nfs_mark_request_commit(struct nfs_page *req, 439 struct pnfs_layout_segment *lseg, 440 struct nfs_commit_info *cinfo); 441 int nfs_generic_commit_list(struct inode *inode, struct list_head *head, 442 int how, struct nfs_commit_info *cinfo); 443 void nfs_retry_commit(struct list_head *page_list, 444 struct pnfs_layout_segment *lseg, 445 struct nfs_commit_info *cinfo); 446 void nfs_commitdata_release(struct nfs_commit_data *data); 447 void nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst, 448 struct nfs_commit_info *cinfo); 449 void nfs_request_remove_commit_list(struct nfs_page *req, 450 struct nfs_commit_info *cinfo); 451 void nfs_init_cinfo(struct nfs_commit_info *cinfo, 452 struct inode *inode, 453 struct nfs_direct_req *dreq); 454 455 #ifdef CONFIG_MIGRATION 456 extern int nfs_migrate_page(struct address_space *, 457 struct page *, struct page *, enum migrate_mode); 458 #else 459 #define nfs_migrate_page NULL 460 #endif 461 462 /* direct.c */ 463 void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo, 464 struct nfs_direct_req *dreq); 465 static inline void nfs_inode_dio_wait(struct inode *inode) 466 { 467 inode_dio_wait(inode); 468 } 469 extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq); 470 471 /* nfs4proc.c */ 472 extern void __nfs4_read_done_cb(struct nfs_read_data *); 473 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp, 474 const struct rpc_timeout *timeparms, 475 const char *ip_addr, 476 rpc_authflavor_t authflavour); 477 extern int _nfs4_call_sync(struct rpc_clnt *clnt, 478 struct nfs_server *server, 479 struct rpc_message *msg, 480 struct nfs4_sequence_args *args, 481 struct nfs4_sequence_res *res, 482 int cache_reply); 483 extern int _nfs4_call_sync_session(struct rpc_clnt *clnt, 484 struct nfs_server *server, 485 struct rpc_message *msg, 486 struct nfs4_sequence_args *args, 487 struct nfs4_sequence_res *res, 488 int cache_reply); 489 extern int nfs40_walk_client_list(struct nfs_client *clp, 490 struct nfs_client **result, 491 struct rpc_cred *cred); 492 extern int nfs41_walk_client_list(struct nfs_client *clp, 493 struct nfs_client **result, 494 struct rpc_cred *cred); 495 496 /* 497 * Determine the device name as a string 498 */ 499 static inline char *nfs_devname(struct dentry *dentry, 500 char *buffer, ssize_t buflen) 501 { 502 char *dummy; 503 return nfs_path(&dummy, dentry, buffer, buflen, NFS_PATH_CANONICAL); 504 } 505 506 /* 507 * Determine the actual block size (and log2 thereof) 508 */ 509 static inline 510 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp) 511 { 512 /* make sure blocksize is a power of two */ 513 if ((bsize & (bsize - 1)) || nrbitsp) { 514 unsigned char nrbits; 515 516 for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--) 517 ; 518 bsize = 1 << nrbits; 519 if (nrbitsp) 520 *nrbitsp = nrbits; 521 } 522 523 return bsize; 524 } 525 526 /* 527 * Calculate the number of 512byte blocks used. 528 */ 529 static inline blkcnt_t nfs_calc_block_size(u64 tsize) 530 { 531 blkcnt_t used = (tsize + 511) >> 9; 532 return (used > ULONG_MAX) ? ULONG_MAX : used; 533 } 534 535 /* 536 * Compute and set NFS server blocksize 537 */ 538 static inline 539 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp) 540 { 541 if (bsize < NFS_MIN_FILE_IO_SIZE) 542 bsize = NFS_DEF_FILE_IO_SIZE; 543 else if (bsize >= NFS_MAX_FILE_IO_SIZE) 544 bsize = NFS_MAX_FILE_IO_SIZE; 545 546 return nfs_block_bits(bsize, nrbitsp); 547 } 548 549 /* 550 * Determine the maximum file size for a superblock 551 */ 552 static inline 553 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize) 554 { 555 sb->s_maxbytes = (loff_t)maxfilesize; 556 if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0) 557 sb->s_maxbytes = MAX_LFS_FILESIZE; 558 } 559 560 /* 561 * Determine the number of bytes of data the page contains 562 */ 563 static inline 564 unsigned int nfs_page_length(struct page *page) 565 { 566 loff_t i_size = i_size_read(page_file_mapping(page)->host); 567 568 if (i_size > 0) { 569 pgoff_t page_index = page_file_index(page); 570 pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; 571 if (page_index < end_index) 572 return PAGE_CACHE_SIZE; 573 if (page_index == end_index) 574 return ((i_size - 1) & ~PAGE_CACHE_MASK) + 1; 575 } 576 return 0; 577 } 578 579 /* 580 * Convert a umode to a dirent->d_type 581 */ 582 static inline 583 unsigned char nfs_umode_to_dtype(umode_t mode) 584 { 585 return (mode >> 12) & 15; 586 } 587 588 /* 589 * Determine the number of pages in an array of length 'len' and 590 * with a base offset of 'base' 591 */ 592 static inline 593 unsigned int nfs_page_array_len(unsigned int base, size_t len) 594 { 595 return ((unsigned long)len + (unsigned long)base + 596 PAGE_SIZE - 1) >> PAGE_SHIFT; 597 } 598 599 /* 600 * Convert a struct timespec into a 64-bit change attribute 601 * 602 * This does approximately the same thing as timespec_to_ns(), 603 * but for calculation efficiency, we multiply the seconds by 604 * 1024*1024*1024. 605 */ 606 static inline 607 u64 nfs_timespec_to_change_attr(const struct timespec *ts) 608 { 609 return ((u64)ts->tv_sec << 30) + ts->tv_nsec; 610 } 611