xref: /openbmc/linux/fs/nfs/internal.h (revision a956beda)
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 #include <linux/nfs_page.h>
10 
11 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
12 
13 struct nfs_string;
14 
15 /* Maximum number of readahead requests
16  * FIXME: this should really be a sysctl so that users may tune it to suit
17  *        their needs. People that do NFS over a slow network, might for
18  *        instance want to reduce it to something closer to 1 for improved
19  *        interactive response.
20  */
21 #define NFS_MAX_READAHEAD	(RPC_DEF_SLOT_TABLE - 1)
22 
23 static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
24 {
25 	if (!nfs_fsid_equal(&NFS_SB(parent)->fsid, &fattr->fsid))
26 		fattr->valid |= NFS_ATTR_FATTR_MOUNTPOINT;
27 }
28 
29 static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
30 {
31 	if (((fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID) == 0) ||
32 	    (((fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT) == 0) &&
33 	     ((fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) == 0)))
34 		return 0;
35 	return 1;
36 }
37 
38 struct nfs_clone_mount {
39 	const struct super_block *sb;
40 	const struct dentry *dentry;
41 	struct nfs_fh *fh;
42 	struct nfs_fattr *fattr;
43 	char *hostname;
44 	char *mnt_path;
45 	struct sockaddr *addr;
46 	size_t addrlen;
47 	rpc_authflavor_t authflavor;
48 };
49 
50 /*
51  * Note: RFC 1813 doesn't limit the number of auth flavors that
52  * a server can return, so make something up.
53  */
54 #define NFS_MAX_SECFLAVORS	(12)
55 
56 /*
57  * Value used if the user did not specify a port value.
58  */
59 #define NFS_UNSPEC_PORT		(-1)
60 
61 #define NFS_UNSPEC_RETRANS	(UINT_MAX)
62 #define NFS_UNSPEC_TIMEO	(UINT_MAX)
63 
64 /*
65  * Maximum number of pages that readdir can use for creating
66  * a vmapped array of pages.
67  */
68 #define NFS_MAX_READDIR_PAGES 8
69 
70 struct nfs_client_initdata {
71 	unsigned long init_flags;
72 	const char *hostname;			/* Hostname of the server */
73 	const struct sockaddr *addr;		/* Address of the server */
74 	const char *nodename;			/* Hostname of the client */
75 	const char *ip_addr;			/* IP address of the client */
76 	size_t addrlen;
77 	struct nfs_subversion *nfs_mod;
78 	int proto;
79 	u32 minorversion;
80 	struct net *net;
81 	const struct rpc_timeout *timeparms;
82 };
83 
84 /*
85  * In-kernel mount arguments
86  */
87 struct nfs_parsed_mount_data {
88 	int			flags;
89 	unsigned int		rsize, wsize;
90 	unsigned int		timeo, retrans;
91 	unsigned int		acregmin, acregmax,
92 				acdirmin, acdirmax;
93 	unsigned int		namlen;
94 	unsigned int		options;
95 	unsigned int		bsize;
96 	struct nfs_auth_info	auth_info;
97 	rpc_authflavor_t	selected_flavor;
98 	char			*client_address;
99 	unsigned int		version;
100 	unsigned int		minorversion;
101 	char			*fscache_uniq;
102 	bool			need_mount;
103 
104 	struct {
105 		struct sockaddr_storage	address;
106 		size_t			addrlen;
107 		char			*hostname;
108 		u32			version;
109 		int			port;
110 		unsigned short		protocol;
111 	} mount_server;
112 
113 	struct {
114 		struct sockaddr_storage	address;
115 		size_t			addrlen;
116 		char			*hostname;
117 		char			*export_path;
118 		int			port;
119 		unsigned short		protocol;
120 	} nfs_server;
121 
122 	struct security_mnt_opts lsm_opts;
123 	struct net		*net;
124 };
125 
126 /* mount_clnt.c */
127 struct nfs_mount_request {
128 	struct sockaddr		*sap;
129 	size_t			salen;
130 	char			*hostname;
131 	char			*dirpath;
132 	u32			version;
133 	unsigned short		protocol;
134 	struct nfs_fh		*fh;
135 	int			noresvport;
136 	unsigned int		*auth_flav_len;
137 	rpc_authflavor_t	*auth_flavs;
138 	struct net		*net;
139 };
140 
141 struct nfs_mount_info {
142 	void (*fill_super)(struct super_block *, struct nfs_mount_info *);
143 	int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
144 	struct nfs_parsed_mount_data *parsed;
145 	struct nfs_clone_mount *cloned;
146 	struct nfs_fh *mntfh;
147 };
148 
149 extern int nfs_mount(struct nfs_mount_request *info);
150 extern void nfs_umount(const struct nfs_mount_request *info);
151 
152 /* client.c */
153 extern const struct rpc_program nfs_program;
154 extern void nfs_clients_init(struct net *net);
155 extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
156 int nfs_create_rpc_client(struct nfs_client *, const struct nfs_client_initdata *, rpc_authflavor_t);
157 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *,
158 				  rpc_authflavor_t);
159 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
160 void nfs_server_insert_lists(struct nfs_server *);
161 void nfs_server_remove_lists(struct nfs_server *);
162 void nfs_init_timeout_values(struct rpc_timeout *to, int proto, int timeo, int retrans);
163 int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
164 		rpc_authflavor_t);
165 struct nfs_server *nfs_alloc_server(void);
166 void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
167 
168 extern void nfs_cleanup_cb_ident_idr(struct net *);
169 extern void nfs_put_client(struct nfs_client *);
170 extern void nfs_free_client(struct nfs_client *);
171 extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
172 extern struct nfs_client *
173 nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
174 				struct nfs4_sessionid *, u32);
175 extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
176 					struct nfs_subversion *);
177 extern struct nfs_server *nfs4_create_server(
178 					struct nfs_mount_info *,
179 					struct nfs_subversion *);
180 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
181 						      struct nfs_fh *);
182 extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
183 					struct sockaddr *sap, size_t salen,
184 					struct net *net);
185 extern void nfs_free_server(struct nfs_server *server);
186 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
187 					   struct nfs_fh *,
188 					   struct nfs_fattr *,
189 					   rpc_authflavor_t);
190 extern int nfs_wait_client_init_complete(const struct nfs_client *clp);
191 extern void nfs_mark_client_ready(struct nfs_client *clp, int state);
192 extern struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
193 					     const struct sockaddr *ds_addr,
194 					     int ds_addrlen, int ds_proto,
195 					     unsigned int ds_timeo,
196 					     unsigned int ds_retrans,
197 					     u32 minor_version,
198 					     rpc_authflavor_t au_flavor);
199 extern struct rpc_clnt *nfs4_find_or_create_ds_client(struct nfs_client *,
200 						struct inode *);
201 extern struct nfs_client *nfs3_set_ds_client(struct nfs_server *mds_srv,
202 			const struct sockaddr *ds_addr, int ds_addrlen,
203 			int ds_proto, unsigned int ds_timeo,
204 			unsigned int ds_retrans, rpc_authflavor_t au_flavor);
205 #ifdef CONFIG_PROC_FS
206 extern int __init nfs_fs_proc_init(void);
207 extern void nfs_fs_proc_exit(void);
208 extern int nfs_fs_proc_net_init(struct net *net);
209 extern void nfs_fs_proc_net_exit(struct net *net);
210 #else
211 static inline int nfs_fs_proc_net_init(struct net *net)
212 {
213 	return 0;
214 }
215 static inline void nfs_fs_proc_net_exit(struct net *net)
216 {
217 }
218 static inline int nfs_fs_proc_init(void)
219 {
220 	return 0;
221 }
222 static inline void nfs_fs_proc_exit(void)
223 {
224 }
225 #endif
226 
227 /* callback_xdr.c */
228 extern struct svc_version nfs4_callback_version1;
229 extern struct svc_version nfs4_callback_version4;
230 
231 struct nfs_pageio_descriptor;
232 /* pagelist.c */
233 extern int __init nfs_init_nfspagecache(void);
234 extern void nfs_destroy_nfspagecache(void);
235 extern int __init nfs_init_readpagecache(void);
236 extern void nfs_destroy_readpagecache(void);
237 extern int __init nfs_init_writepagecache(void);
238 extern void nfs_destroy_writepagecache(void);
239 
240 extern int __init nfs_init_directcache(void);
241 extern void nfs_destroy_directcache(void);
242 extern void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
243 			      struct nfs_pgio_header *hdr,
244 			      void (*release)(struct nfs_pgio_header *hdr));
245 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos);
246 int nfs_iocounter_wait(struct nfs_lock_context *l_ctx);
247 
248 extern const struct nfs_pageio_ops nfs_pgio_rw_ops;
249 struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *);
250 void nfs_pgio_header_free(struct nfs_pgio_header *);
251 void nfs_pgio_data_destroy(struct nfs_pgio_header *);
252 int nfs_generic_pgio(struct nfs_pageio_descriptor *, struct nfs_pgio_header *);
253 int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr,
254 		      struct rpc_cred *cred, const struct nfs_rpc_ops *rpc_ops,
255 		      const struct rpc_call_ops *call_ops, int how, int flags);
256 void nfs_free_request(struct nfs_page *req);
257 struct nfs_pgio_mirror *
258 nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc);
259 
260 static inline bool nfs_pgio_has_mirroring(struct nfs_pageio_descriptor *desc)
261 {
262 	WARN_ON_ONCE(desc->pg_mirror_count < 1);
263 	return desc->pg_mirror_count > 1;
264 }
265 
266 static inline bool nfs_match_open_context(const struct nfs_open_context *ctx1,
267 		const struct nfs_open_context *ctx2)
268 {
269 	return ctx1->cred == ctx2->cred && ctx1->state == ctx2->state;
270 }
271 
272 /* nfs2xdr.c */
273 extern struct rpc_procinfo nfs_procedures[];
274 extern int nfs2_decode_dirent(struct xdr_stream *,
275 				struct nfs_entry *, int);
276 
277 /* nfs3xdr.c */
278 extern struct rpc_procinfo nfs3_procedures[];
279 extern int nfs3_decode_dirent(struct xdr_stream *,
280 				struct nfs_entry *, int);
281 
282 /* nfs4xdr.c */
283 #if IS_ENABLED(CONFIG_NFS_V4)
284 extern int nfs4_decode_dirent(struct xdr_stream *,
285 				struct nfs_entry *, int);
286 #endif
287 #ifdef CONFIG_NFS_V4_1
288 extern const u32 nfs41_maxread_overhead;
289 extern const u32 nfs41_maxwrite_overhead;
290 extern const u32 nfs41_maxgetdevinfo_overhead;
291 #endif
292 
293 /* nfs4proc.c */
294 #if IS_ENABLED(CONFIG_NFS_V4)
295 extern struct rpc_procinfo nfs4_procedures[];
296 #endif
297 
298 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
299 extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
300 static inline struct nfs4_label *
301 nfs4_label_copy(struct nfs4_label *dst, struct nfs4_label *src)
302 {
303 	if (!dst || !src)
304 		return NULL;
305 
306 	if (src->len > NFS4_MAXLABELLEN)
307 		return NULL;
308 
309 	dst->lfs = src->lfs;
310 	dst->pi = src->pi;
311 	dst->len = src->len;
312 	memcpy(dst->label, src->label, src->len);
313 
314 	return dst;
315 }
316 static inline void nfs4_label_free(struct nfs4_label *label)
317 {
318 	if (label) {
319 		kfree(label->label);
320 		kfree(label);
321 	}
322 	return;
323 }
324 
325 static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
326 {
327 	if (nfs_server_capable(&nfsi->vfs_inode, NFS_CAP_SECURITY_LABEL))
328 		nfsi->cache_validity |= NFS_INO_INVALID_LABEL;
329 }
330 #else
331 static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
332 static inline void nfs4_label_free(void *label) {}
333 static inline void nfs_zap_label_cache_locked(struct nfs_inode *nfsi)
334 {
335 }
336 static inline struct nfs4_label *
337 nfs4_label_copy(struct nfs4_label *dst, struct nfs4_label *src)
338 {
339 	return NULL;
340 }
341 #endif /* CONFIG_NFS_V4_SECURITY_LABEL */
342 
343 /* proc.c */
344 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
345 extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
346 			   const struct nfs_client_initdata *);
347 
348 /* dir.c */
349 extern void nfs_force_use_readdirplus(struct inode *dir);
350 extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
351 					    struct shrink_control *sc);
352 extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
353 					   struct shrink_control *sc);
354 struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
355 int nfs_create(struct inode *, struct dentry *, umode_t, bool);
356 int nfs_mkdir(struct inode *, struct dentry *, umode_t);
357 int nfs_rmdir(struct inode *, struct dentry *);
358 int nfs_unlink(struct inode *, struct dentry *);
359 int nfs_symlink(struct inode *, struct dentry *, const char *);
360 int nfs_link(struct dentry *, struct inode *, struct dentry *);
361 int nfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
362 int nfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
363 
364 /* file.c */
365 int nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
366 loff_t nfs_file_llseek(struct file *, loff_t, int);
367 ssize_t nfs_file_read(struct kiocb *, struct iov_iter *);
368 ssize_t nfs_file_splice_read(struct file *, loff_t *, struct pipe_inode_info *,
369 			     size_t, unsigned int);
370 int nfs_file_mmap(struct file *, struct vm_area_struct *);
371 ssize_t nfs_file_write(struct kiocb *, struct iov_iter *);
372 int nfs_file_release(struct inode *, struct file *);
373 int nfs_lock(struct file *, int, struct file_lock *);
374 int nfs_flock(struct file *, int, struct file_lock *);
375 int nfs_check_flags(int);
376 
377 /* inode.c */
378 extern struct workqueue_struct *nfsiod_workqueue;
379 extern struct inode *nfs_alloc_inode(struct super_block *sb);
380 extern void nfs_destroy_inode(struct inode *);
381 extern int nfs_write_inode(struct inode *, struct writeback_control *);
382 extern int nfs_drop_inode(struct inode *);
383 extern void nfs_clear_inode(struct inode *);
384 extern void nfs_evict_inode(struct inode *);
385 void nfs_zap_acl_cache(struct inode *inode);
386 extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);
387 extern int nfs_wait_atomic_killable(atomic_t *p);
388 
389 /* super.c */
390 extern const struct super_operations nfs_sops;
391 extern struct file_system_type nfs_fs_type;
392 extern struct file_system_type nfs_xdev_fs_type;
393 #if IS_ENABLED(CONFIG_NFS_V4)
394 extern struct file_system_type nfs4_xdev_fs_type;
395 extern struct file_system_type nfs4_referral_fs_type;
396 #endif
397 bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
398 struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
399 			struct nfs_subversion *);
400 void nfs_initialise_sb(struct super_block *);
401 int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
402 int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
403 struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
404 				   struct nfs_mount_info *, struct nfs_subversion *);
405 struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
406 struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
407 		const char *, struct nfs_mount_info *);
408 void nfs_kill_super(struct super_block *);
409 void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
410 
411 extern struct rpc_stat nfs_rpcstat;
412 
413 extern int __init register_nfs_fs(void);
414 extern void __exit unregister_nfs_fs(void);
415 extern bool nfs_sb_active(struct super_block *sb);
416 extern void nfs_sb_deactive(struct super_block *sb);
417 
418 /* io.c */
419 extern void nfs_start_io_read(struct inode *inode);
420 extern void nfs_end_io_read(struct inode *inode);
421 extern void nfs_start_io_write(struct inode *inode);
422 extern void nfs_end_io_write(struct inode *inode);
423 extern void nfs_start_io_direct(struct inode *inode);
424 extern void nfs_end_io_direct(struct inode *inode);
425 
426 static inline bool nfs_file_io_is_buffered(struct nfs_inode *nfsi)
427 {
428 	return test_bit(NFS_INO_ODIRECT, &nfsi->flags) == 0;
429 }
430 
431 /* namespace.c */
432 #define NFS_PATH_CANONICAL 1
433 extern char *nfs_path(char **p, struct dentry *dentry,
434 		      char *buffer, ssize_t buflen, unsigned flags);
435 extern struct vfsmount *nfs_d_automount(struct path *path);
436 struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
437 			      struct nfs_fh *, struct nfs_fattr *);
438 struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
439 				 struct nfs_fattr *, rpc_authflavor_t);
440 
441 /* getroot.c */
442 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
443 				   const char *);
444 #if IS_ENABLED(CONFIG_NFS_V4)
445 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
446 				    const char *);
447 
448 extern int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool);
449 #endif
450 
451 struct nfs_pgio_completion_ops;
452 /* read.c */
453 extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
454 			struct inode *inode, bool force_mds,
455 			const struct nfs_pgio_completion_ops *compl_ops);
456 extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
457 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
458 
459 /* super.c */
460 void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
461 void nfs_umount_begin(struct super_block *);
462 int  nfs_statfs(struct dentry *, struct kstatfs *);
463 int  nfs_show_options(struct seq_file *, struct dentry *);
464 int  nfs_show_devname(struct seq_file *, struct dentry *);
465 int  nfs_show_path(struct seq_file *, struct dentry *);
466 int  nfs_show_stats(struct seq_file *, struct dentry *);
467 int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
468 
469 /* write.c */
470 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
471 			struct inode *inode, int ioflags, bool force_mds,
472 			const struct nfs_pgio_completion_ops *compl_ops);
473 extern void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio);
474 extern void nfs_commit_free(struct nfs_commit_data *p);
475 extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
476 extern void nfs_commit_prepare(struct rpc_task *task, void *calldata);
477 extern int nfs_initiate_commit(struct rpc_clnt *clnt,
478 			       struct nfs_commit_data *data,
479 			       const struct nfs_rpc_ops *nfs_ops,
480 			       const struct rpc_call_ops *call_ops,
481 			       int how, int flags);
482 extern void nfs_init_commit(struct nfs_commit_data *data,
483 			    struct list_head *head,
484 			    struct pnfs_layout_segment *lseg,
485 			    struct nfs_commit_info *cinfo);
486 int nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
487 			 struct nfs_commit_info *cinfo, int max);
488 unsigned long nfs_reqs_to_commit(struct nfs_commit_info *);
489 int nfs_scan_commit(struct inode *inode, struct list_head *dst,
490 		    struct nfs_commit_info *cinfo);
491 void nfs_mark_request_commit(struct nfs_page *req,
492 			     struct pnfs_layout_segment *lseg,
493 			     struct nfs_commit_info *cinfo,
494 			     u32 ds_commit_idx);
495 int nfs_write_need_commit(struct nfs_pgio_header *);
496 void nfs_writeback_update_inode(struct nfs_pgio_header *hdr);
497 int nfs_commit_file(struct file *file, struct nfs_write_verifier *verf);
498 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
499 			    int how, struct nfs_commit_info *cinfo);
500 void nfs_retry_commit(struct list_head *page_list,
501 		      struct pnfs_layout_segment *lseg,
502 		      struct nfs_commit_info *cinfo,
503 		      u32 ds_commit_idx);
504 void nfs_commitdata_release(struct nfs_commit_data *data);
505 void nfs_request_add_commit_list(struct nfs_page *req,
506 				 struct nfs_commit_info *cinfo);
507 void nfs_request_add_commit_list_locked(struct nfs_page *req,
508 		struct list_head *dst,
509 		struct nfs_commit_info *cinfo);
510 void nfs_request_remove_commit_list(struct nfs_page *req,
511 				    struct nfs_commit_info *cinfo);
512 void nfs_init_cinfo(struct nfs_commit_info *cinfo,
513 		    struct inode *inode,
514 		    struct nfs_direct_req *dreq);
515 int nfs_key_timeout_notify(struct file *filp, struct inode *inode);
516 bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode);
517 void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio);
518 
519 int nfs_filemap_write_and_wait_range(struct address_space *mapping,
520 		loff_t lstart, loff_t lend);
521 
522 #ifdef CONFIG_NFS_V4_1
523 static inline
524 void nfs_clear_pnfs_ds_commit_verifiers(struct pnfs_ds_commit_info *cinfo)
525 {
526 	int i;
527 
528 	for (i = 0; i < cinfo->nbuckets; i++)
529 		cinfo->buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
530 }
531 #else
532 static inline
533 void nfs_clear_pnfs_ds_commit_verifiers(struct pnfs_ds_commit_info *cinfo)
534 {
535 }
536 #endif
537 
538 
539 #ifdef CONFIG_MIGRATION
540 extern int nfs_migrate_page(struct address_space *,
541 		struct page *, struct page *, enum migrate_mode);
542 #else
543 #define nfs_migrate_page NULL
544 #endif
545 
546 static inline int
547 nfs_write_verifier_cmp(const struct nfs_write_verifier *v1,
548 		const struct nfs_write_verifier *v2)
549 {
550 	return memcmp(v1->data, v2->data, sizeof(v1->data));
551 }
552 
553 /* unlink.c */
554 extern struct rpc_task *
555 nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
556 		 struct dentry *old_dentry, struct dentry *new_dentry,
557 		 void (*complete)(struct rpc_task *, struct nfs_renamedata *));
558 extern int nfs_sillyrename(struct inode *dir, struct dentry *dentry);
559 
560 /* direct.c */
561 void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
562 			      struct nfs_direct_req *dreq);
563 extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);
564 
565 /* nfs4proc.c */
566 extern void __nfs4_read_done_cb(struct nfs_pgio_header *);
567 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
568 			    const struct nfs_client_initdata *);
569 extern int nfs40_walk_client_list(struct nfs_client *clp,
570 				struct nfs_client **result,
571 				struct rpc_cred *cred);
572 extern int nfs41_walk_client_list(struct nfs_client *clp,
573 				struct nfs_client **result,
574 				struct rpc_cred *cred);
575 
576 static inline struct inode *nfs_igrab_and_active(struct inode *inode)
577 {
578 	inode = igrab(inode);
579 	if (inode != NULL && !nfs_sb_active(inode->i_sb)) {
580 		iput(inode);
581 		inode = NULL;
582 	}
583 	return inode;
584 }
585 
586 static inline void nfs_iput_and_deactive(struct inode *inode)
587 {
588 	if (inode != NULL) {
589 		struct super_block *sb = inode->i_sb;
590 
591 		iput(inode);
592 		nfs_sb_deactive(sb);
593 	}
594 }
595 
596 /*
597  * Determine the device name as a string
598  */
599 static inline char *nfs_devname(struct dentry *dentry,
600 				char *buffer, ssize_t buflen)
601 {
602 	char *dummy;
603 	return nfs_path(&dummy, dentry, buffer, buflen, NFS_PATH_CANONICAL);
604 }
605 
606 /*
607  * Determine the actual block size (and log2 thereof)
608  */
609 static inline
610 unsigned long nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
611 {
612 	/* make sure blocksize is a power of two */
613 	if ((bsize & (bsize - 1)) || nrbitsp) {
614 		unsigned char	nrbits;
615 
616 		for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
617 			;
618 		bsize = 1 << nrbits;
619 		if (nrbitsp)
620 			*nrbitsp = nrbits;
621 	}
622 
623 	return bsize;
624 }
625 
626 /*
627  * Calculate the number of 512byte blocks used.
628  */
629 static inline blkcnt_t nfs_calc_block_size(u64 tsize)
630 {
631 	blkcnt_t used = (tsize + 511) >> 9;
632 	return (used > ULONG_MAX) ? ULONG_MAX : used;
633 }
634 
635 /*
636  * Compute and set NFS server blocksize
637  */
638 static inline
639 unsigned long nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
640 {
641 	if (bsize < NFS_MIN_FILE_IO_SIZE)
642 		bsize = NFS_DEF_FILE_IO_SIZE;
643 	else if (bsize >= NFS_MAX_FILE_IO_SIZE)
644 		bsize = NFS_MAX_FILE_IO_SIZE;
645 
646 	return nfs_block_bits(bsize, nrbitsp);
647 }
648 
649 /*
650  * Determine the maximum file size for a superblock
651  */
652 static inline
653 void nfs_super_set_maxbytes(struct super_block *sb, __u64 maxfilesize)
654 {
655 	sb->s_maxbytes = (loff_t)maxfilesize;
656 	if (sb->s_maxbytes > MAX_LFS_FILESIZE || sb->s_maxbytes <= 0)
657 		sb->s_maxbytes = MAX_LFS_FILESIZE;
658 }
659 
660 /*
661  * Record the page as unstable and mark its inode as dirty.
662  */
663 static inline
664 void nfs_mark_page_unstable(struct page *page, struct nfs_commit_info *cinfo)
665 {
666 	if (!cinfo->dreq) {
667 		struct inode *inode = page_file_mapping(page)->host;
668 
669 		inc_node_page_state(page, NR_UNSTABLE_NFS);
670 		inc_wb_stat(&inode_to_bdi(inode)->wb, WB_RECLAIMABLE);
671 		__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
672 	}
673 }
674 
675 /*
676  * Determine the number of bytes of data the page contains
677  */
678 static inline
679 unsigned int nfs_page_length(struct page *page)
680 {
681 	loff_t i_size = i_size_read(page_file_mapping(page)->host);
682 
683 	if (i_size > 0) {
684 		pgoff_t page_index = page_file_index(page);
685 		pgoff_t end_index = (i_size - 1) >> PAGE_SHIFT;
686 		if (page_index < end_index)
687 			return PAGE_SIZE;
688 		if (page_index == end_index)
689 			return ((i_size - 1) & ~PAGE_MASK) + 1;
690 	}
691 	return 0;
692 }
693 
694 /*
695  * Convert a umode to a dirent->d_type
696  */
697 static inline
698 unsigned char nfs_umode_to_dtype(umode_t mode)
699 {
700 	return (mode >> 12) & 15;
701 }
702 
703 /*
704  * Determine the number of pages in an array of length 'len' and
705  * with a base offset of 'base'
706  */
707 static inline
708 unsigned int nfs_page_array_len(unsigned int base, size_t len)
709 {
710 	return ((unsigned long)len + (unsigned long)base +
711 		PAGE_SIZE - 1) >> PAGE_SHIFT;
712 }
713 
714 /*
715  * Convert a struct timespec into a 64-bit change attribute
716  *
717  * This does approximately the same thing as timespec_to_ns(),
718  * but for calculation efficiency, we multiply the seconds by
719  * 1024*1024*1024.
720  */
721 static inline
722 u64 nfs_timespec_to_change_attr(const struct timespec *ts)
723 {
724 	return ((u64)ts->tv_sec << 30) + ts->tv_nsec;
725 }
726 
727 #ifdef CONFIG_CRC32
728 /**
729  * nfs_fhandle_hash - calculate the crc32 hash for the filehandle
730  * @fh - pointer to filehandle
731  *
732  * returns a crc32 hash for the filehandle that is compatible with
733  * the one displayed by "wireshark".
734  */
735 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
736 {
737 	return ~crc32_le(0xFFFFFFFF, &fh->data[0], fh->size);
738 }
739 static inline u32 nfs_stateid_hash(const nfs4_stateid *stateid)
740 {
741 	return ~crc32_le(0xFFFFFFFF, &stateid->other[0],
742 				NFS4_STATEID_OTHER_SIZE);
743 }
744 #else
745 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
746 {
747 	return 0;
748 }
749 static inline u32 nfs_stateid_hash(nfs4_stateid *stateid)
750 {
751 	return 0;
752 }
753 #endif
754 
755 static inline bool nfs_error_is_fatal(int err)
756 {
757 	switch (err) {
758 	case -ERESTARTSYS:
759 	case -EIO:
760 	case -ENOSPC:
761 	case -EROFS:
762 	case -E2BIG:
763 		return true;
764 	default:
765 		return false;
766 	}
767 }
768