tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
12struct 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
22static 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
28static 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 return 1;
35}
36
37struct nfs_clone_mount {
38 const struct super_block *sb;
39 const struct dentry *dentry;
40 struct nfs_fh *fh;
41 struct nfs_fattr *fattr;
42 char *hostname;
43 char *mnt_path;
44 struct sockaddr *addr;
45 size_t addrlen;
46 rpc_authflavor_t authflavor;
47};
48
49/*
50 * Note: RFC 1813 doesn't limit the number of auth flavors that
51 * a server can return, so make something up.
52 */
53#define NFS_MAX_SECFLAVORS (12)
54
55/*
56 * Value used if the user did not specify a port value.
57 */
58#define NFS_UNSPEC_PORT (-1)
59
60/*
61 * Maximum number of pages that readdir can use for creating
62 * a vmapped array of pages.
63 */
64#define NFS_MAX_READDIR_PAGES 8
65
66struct nfs_client_initdata {
67 unsigned long init_flags;
68 const char *hostname;
69 const struct sockaddr *addr;
70 size_t addrlen;
71 struct nfs_subversion *nfs_mod;
72 int proto;
73 u32 minorversion;
74 struct net *net;
75};
76
77/*
78 * In-kernel mount arguments
79 */
80struct nfs_parsed_mount_data {
81 int flags;
82 unsigned int rsize, wsize;
83 unsigned int timeo, retrans;
84 unsigned int acregmin, acregmax,
85 acdirmin, acdirmax;
86 unsigned int namlen;
87 unsigned int options;
88 unsigned int bsize;
89 struct nfs_auth_info auth_info;
90 rpc_authflavor_t selected_flavor;
91 char *client_address;
92 unsigned int version;
93 unsigned int minorversion;
94 char *fscache_uniq;
95 bool need_mount;
96
97 struct {
98 struct sockaddr_storage address;
99 size_t addrlen;
100 char *hostname;
101 u32 version;
102 int port;
103 unsigned short protocol;
104 } mount_server;
105
106 struct {
107 struct sockaddr_storage address;
108 size_t addrlen;
109 char *hostname;
110 char *export_path;
111 int port;
112 unsigned short protocol;
113 } nfs_server;
114
115 struct security_mnt_opts lsm_opts;
116 struct net *net;
117};
118
119/* mount_clnt.c */
120struct nfs_mount_request {
121 struct sockaddr *sap;
122 size_t salen;
123 char *hostname;
124 char *dirpath;
125 u32 version;
126 unsigned short protocol;
127 struct nfs_fh *fh;
128 int noresvport;
129 unsigned int *auth_flav_len;
130 rpc_authflavor_t *auth_flavs;
131 struct net *net;
132};
133
134struct nfs_mount_info {
135 void (*fill_super)(struct super_block *, struct nfs_mount_info *);
136 int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
137 struct nfs_parsed_mount_data *parsed;
138 struct nfs_clone_mount *cloned;
139 struct nfs_fh *mntfh;
140};
141
142extern int nfs_mount(struct nfs_mount_request *info);
143extern void nfs_umount(const struct nfs_mount_request *info);
144
145/* client.c */
146extern const struct rpc_program nfs_program;
147extern void nfs_clients_init(struct net *net);
148extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
149int nfs_create_rpc_client(struct nfs_client *, const struct rpc_timeout *, rpc_authflavor_t);
150struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
151 const struct rpc_timeout *, const char *,
152 rpc_authflavor_t);
153int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
154void nfs_server_insert_lists(struct nfs_server *);
155void nfs_server_remove_lists(struct nfs_server *);
156void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
157int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
158 rpc_authflavor_t);
159struct nfs_server *nfs_alloc_server(void);
160void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
161
162extern void nfs_cleanup_cb_ident_idr(struct net *);
163extern void nfs_put_client(struct nfs_client *);
164extern void nfs_free_client(struct nfs_client *);
165extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
166extern struct nfs_client *
167nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
168 struct nfs4_sessionid *, u32);
169extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
170 struct nfs_subversion *);
171extern struct nfs_server *nfs4_create_server(
172 struct nfs_mount_info *,
173 struct nfs_subversion *);
174extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
175 struct nfs_fh *);
176extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
177 struct sockaddr *sap, size_t salen,
178 struct net *net);
179extern void nfs_free_server(struct nfs_server *server);
180extern struct nfs_server *nfs_clone_server(struct nfs_server *,
181 struct nfs_fh *,
182 struct nfs_fattr *,
183 rpc_authflavor_t);
184extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
185extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
186extern struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
187 const struct sockaddr *ds_addr,
188 int ds_addrlen, int ds_proto,
189 unsigned int ds_timeo,
190 unsigned int ds_retrans);
191extern struct rpc_clnt *nfs4_find_or_create_ds_client(struct nfs_client *,
192 struct inode *);
193#ifdef CONFIG_PROC_FS
194extern int __init nfs_fs_proc_init(void);
195extern void nfs_fs_proc_exit(void);
196extern int nfs_fs_proc_net_init(struct net *net);
197extern void nfs_fs_proc_net_exit(struct net *net);
198#else
199static inline int nfs_fs_proc_net_init(struct net *net)
200{
201 return 0;
202}
203static inline void nfs_fs_proc_net_exit(struct net *net)
204{
205}
206static inline int nfs_fs_proc_init(void)
207{
208 return 0;
209}
210static inline void nfs_fs_proc_exit(void)
211{
212}
213#endif
214
215#ifdef CONFIG_NFS_V4_1
216int nfs_sockaddr_match_ipaddr(const struct sockaddr *, const struct sockaddr *);
217#endif
218
219/* callback_xdr.c */
220extern struct svc_version nfs4_callback_version1;
221extern struct svc_version nfs4_callback_version4;
222
223struct nfs_pageio_descriptor;
224/* pagelist.c */
225extern int __init nfs_init_nfspagecache(void);
226extern void nfs_destroy_nfspagecache(void);
227extern int __init nfs_init_readpagecache(void);
228extern void nfs_destroy_readpagecache(void);
229extern int __init nfs_init_writepagecache(void);
230extern void nfs_destroy_writepagecache(void);
231
232extern int __init nfs_init_directcache(void);
233extern void nfs_destroy_directcache(void);
234extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
235 struct nfs_pgio_header *hdr,
236 void (*release)(struct nfs_pgio_header *hdr));
237void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
238int nfs_iocounter_wait(struct nfs_io_counter *c);
239
240extern const struct nfs_pageio_ops nfs_pgio_rw_ops;
241struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *);
242void nfs_pgio_header_free(struct nfs_pgio_header *);
243void nfs_pgio_data_destroy(struct nfs_pgio_header *);
244int nfs_generic_pgio(struct nfs_pageio_descriptor *, struct nfs_pgio_header *);
245int nfs_initiate_pgio(struct rpc_clnt *, struct nfs_pgio_header *,
246 const struct rpc_call_ops *, int, int);
247void nfs_free_request(struct nfs_page *req);
248
249static inline void nfs_iocounter_init(struct nfs_io_counter *c)
250{
251 c->flags = 0;
252 atomic_set(&c->io_count, 0);
253}
254
255/* nfs2xdr.c */
256extern struct rpc_procinfo nfs_procedures[];
257extern int nfs2_decode_dirent(struct xdr_stream *,
258 struct nfs_entry *, int);
259
260/* nfs3xdr.c */
261extern struct rpc_procinfo nfs3_procedures[];
262extern int nfs3_decode_dirent(struct xdr_stream *,
263 struct nfs_entry *, int);
264
265/* nfs4xdr.c */
266#if IS_ENABLED(CONFIG_NFS_V4)
267extern int nfs4_decode_dirent(struct xdr_stream *,
268 struct nfs_entry *, int);
269#endif
270#ifdef CONFIG_NFS_V4_1
271extern const u32 nfs41_maxread_overhead;
272extern const u32 nfs41_maxwrite_overhead;
273extern const u32 nfs41_maxgetdevinfo_overhead;
274#endif
275
276/* nfs4proc.c */
277#if IS_ENABLED(CONFIG_NFS_V4)
278extern struct rpc_procinfo nfs4_procedures[];
279#endif
280
281#ifdef CONFIG_NFS_V4_SECURITY_LABEL
282extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
283static inline void nfs4_label_free(struct nfs4_label *label)
284{
285 if (label) {
286 kfree(label->label);
287 kfree(label);
288 }
289 return;
290}
291
292static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
293{
294 if (nfs_server_capable(&nfsi->vfs_inode, NFS_CAP_SECURITY_LABEL))
295 nfsi->cache_validity |= NFS_INO_INVALID_LABEL;
296}
297#else
298static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
299static inline void nfs4_label_free(void *label) {}
300static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
301{
302}
303#endif /* CONFIG_NFS_V4_SECURITY_LABEL */
304
305/* proc.c */
306void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
307extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
308 const struct rpc_timeout *timeparms,
309 const char *ip_addr);
310
311/* dir.c */
312extern void nfs_force_use_readdirplus(struct inode *dir);
313extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
314 struct shrink_control *sc);
315extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
316 struct shrink_control *sc);
317struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
318int nfs_create(struct inode *, struct dentry *, umode_t, bool);
319int nfs_mkdir(struct inode *, struct dentry *, umode_t);
320int nfs_rmdir(struct inode *, struct dentry *);
321int nfs_unlink(struct inode *, struct dentry *);
322int nfs_symlink(struct inode *, struct dentry *, const char *);
323int nfs_link(struct dentry *, struct inode *, struct dentry *);
324int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
325int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
326
327/* file.c */
328int nfs_file_fsync_commit(struct file *, loff_t, loff_t, int);
329loff_t nfs_file_llseek(struct file *, loff_t, int);
330int nfs_file_flush(struct file *, fl_owner_t);
331ssize_t nfs_file_read(struct kiocb *, struct iov_iter *);
332ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
333 size_t, unsigned int);
334int nfs_file_mmap(struct file *, struct vm_area_struct *);
335ssize_t nfs_file_write(struct kiocb *, struct iov_iter *);
336int nfs_file_release(struct inode *, struct file *);
337int nfs_lock(struct file *, int, struct file_lock *);
338int nfs_flock(struct file *, int, struct file_lock *);
339int nfs_check_flags(int);
340
341/* inode.c */
342extern struct workqueue_struct *nfsiod_workqueue;
343extern struct inode *nfs_alloc_inode(struct super_block *sb);
344extern void nfs_destroy_inode(struct inode *);
345extern int nfs_write_inode(struct inode *, struct writeback_control *);
346extern int nfs_drop_inode(struct inode *);
347extern void nfs_clear_inode(struct inode *);
348extern void nfs_evict_inode(struct inode *);
349void nfs_zap_acl_cache(struct inode *inode);
350extern int nfs_wait_bit_killable(struct wait_bit_key *key);
351
352/* super.c */
353extern const struct super_operations nfs_sops;
354extern struct file_system_type nfs_fs_type;
355extern struct file_system_type nfs_xdev_fs_type;
356#if IS_ENABLED(CONFIG_NFS_V4)
357extern struct file_system_type nfs4_xdev_fs_type;
358extern struct file_system_type nfs4_referral_fs_type;
359#endif
360bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
361struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
362 struct nfs_subversion *);
363void nfs_initialise_sb(struct super_block *);
364int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
365int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
366struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
367 struct nfs_mount_info *, struct nfs_subversion *);
368struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
369struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
370 const char *, struct nfs_mount_info *);
371void nfs_kill_super(struct super_block *);
372void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
373
374extern struct rpc_stat nfs_rpcstat;
375
376extern int __init register_nfs_fs(void);
377extern void __exit unregister_nfs_fs(void);
378extern void nfs_sb_active(struct super_block *sb);
379extern void nfs_sb_deactive(struct super_block *sb);
380
381/* namespace.c */
382#define NFS_PATH_CANONICAL 1
383extern char *nfs_path(char **p, struct dentry *dentry,
384 char *buffer, ssize_t buflen, unsigned flags);
385extern struct vfsmount *nfs_d_automount(struct path *path);
386struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
387 struct nfs_fh *, struct nfs_fattr *);
388struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
389 struct nfs_fattr *, rpc_authflavor_t);
390
391/* getroot.c */
392extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
393 const char *);
394#if IS_ENABLED(CONFIG_NFS_V4)
395extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
396 const char *);
397
398extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool);
399#endif
400
401struct nfs_pgio_completion_ops;
402/* read.c */
403extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
404 struct inode *inode, bool force_mds,
405 const struct nfs_pgio_completion_ops *compl_ops);
406extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
407extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
408
409/* super.c */
410void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
411void nfs_umount_begin(struct super_block *);
412int nfs_statfs(struct dentry *, struct kstatfs *);
413int nfs_show_options(struct seq_file *, struct dentry *);
414int nfs_show_devname(struct seq_file *, struct dentry *);
415int nfs_show_path(struct seq_file *, struct dentry *);
416int nfs_show_stats(struct seq_file *, struct dentry *);
417void nfs_put_super(struct super_block *);
418int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
419
420/* write.c */
421extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
422 struct inode *inode, int ioflags, bool force_mds,
423 const struct nfs_pgio_completion_ops *compl_ops);
424extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
425extern void nfs_commit_free(struct nfs_commit_data *p);
426extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
427extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
428extern int nfs_initiate_commit(struct rpc_clnt *clnt,
429 struct nfs_commit_data *data,
430 const struct rpc_call_ops *call_ops,
431 int how, int flags);
432extern void nfs_init_commit(struct nfs_commit_data *data,
433 struct list_head *head,
434 struct pnfs_layout_segment *lseg,
435 struct nfs_commit_info *cinfo);
436int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
437 struct nfs_commit_info *cinfo, int max);
438unsigned long nfs_reqs_to_commit(struct nfs_commit_info *);
439int nfs_scan_commit(struct inode *inode, struct list_head *dst,
440 struct nfs_commit_info *cinfo);
441void nfs_mark_request_commit(struct nfs_page *req,
442 struct pnfs_layout_segment *lseg,
443 struct nfs_commit_info *cinfo);
444int nfs_write_need_commit(struct nfs_pgio_header *);
445int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
446 int how, struct nfs_commit_info *cinfo);
447void nfs_retry_commit(struct list_head *page_list,
448 struct pnfs_layout_segment *lseg,
449 struct nfs_commit_info *cinfo);
450void nfs_commitdata_release(struct nfs_commit_data *data);
451void nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst,
452 struct nfs_commit_info *cinfo);
453void nfs_request_remove_commit_list(struct nfs_page *req,
454 struct nfs_commit_info *cinfo);
455void nfs_init_cinfo(struct nfs_commit_info *cinfo,
456 struct inode *inode,
457 struct nfs_direct_req *dreq);
458int nfs_key_timeout_notify(struct file *filp, struct inode *inode);
459bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx);
460
461#ifdef CONFIG_MIGRATION
462extern int nfs_migrate_page(struct address_space *,
463 struct page *, struct page *, enum migrate_mode);
464#else
465#define nfs_migrate_page NULL
466#endif
467
468/* unlink.c */
469extern struct rpc_task *
470nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
471 struct dentry *old_dentry, struct dentry *new_dentry,
472 void (*complete)(struct rpc_task *, struct nfs_renamedata *));
473extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
474
475/* direct.c */
476void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
477 struct nfs_direct_req *dreq);
478static inline void nfs_inode_dio_wait(struct inode *inode)
479{
480 inode_dio_wait(inode);
481}
482extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);
483
484/* nfs4proc.c */
485extern void __nfs4_read_done_cb(struct nfs_pgio_header *);
486extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
487 const struct rpc_timeout *timeparms,
488 const char *ip_addr);
489extern int nfs40_walk_client_list(struct nfs_client *clp,
490 struct nfs_client **result,
491 struct rpc_cred *cred);
492extern 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 */
499static 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 */
509static inline
510unsigned 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 */
529static 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 */
538static inline
539unsigned 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 */
552static inline
553void 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 */
563static inline
564unsigned 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 */
582static inline
583unsigned 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 */
592static inline
593unsigned 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 */
606static inline
607u64 nfs_timespec_to_change_attr(const struct timespec *ts)
608{
609 return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
610}
611
612#ifdef CONFIG_CRC32
613/**
614 * nfs_fhandle_hash - calculate the crc32 hash for the filehandle
615 * @fh - pointer to filehandle
616 *
617 * returns a crc32 hash for the filehandle that is compatible with
618 * the one displayed by "wireshark".
619 */
620static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
621{
622 return ~crc32_le(0xFFFFFFFF, &fh->data[0], fh->size);
623}
624#else
625static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
626{
627 return 0;
628}
629#endif