xref: /openbmc/linux/fs/nfs/pnfs.h (revision 034f90b3)
1 /*
2  *  pNFS client data structures.
3  *
4  *  Copyright (c) 2002
5  *  The Regents of the University of Michigan
6  *  All Rights Reserved
7  *
8  *  Dean Hildebrand <dhildebz@umich.edu>
9  *
10  *  Permission is granted to use, copy, create derivative works, and
11  *  redistribute this software and such derivative works for any purpose,
12  *  so long as the name of the University of Michigan is not used in
13  *  any advertising or publicity pertaining to the use or distribution
14  *  of this software without specific, written prior authorization. If
15  *  the above copyright notice or any other identification of the
16  *  University of Michigan is included in any copy of any portion of
17  *  this software, then the disclaimer below must also be included.
18  *
19  *  This software is provided as is, without representation or warranty
20  *  of any kind either express or implied, including without limitation
21  *  the implied warranties of merchantability, fitness for a particular
22  *  purpose, or noninfringement.  The Regents of the University of
23  *  Michigan shall not be liable for any damages, including special,
24  *  indirect, incidental, or consequential damages, with respect to any
25  *  claim arising out of or in connection with the use of the software,
26  *  even if it has been or is hereafter advised of the possibility of
27  *  such damages.
28  */
29 
30 #ifndef FS_NFS_PNFS_H
31 #define FS_NFS_PNFS_H
32 
33 #include <linux/nfs_fs.h>
34 #include <linux/nfs_page.h>
35 #include <linux/workqueue.h>
36 
37 enum {
38 	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
39 	NFS_LSEG_ROC,		/* roc bit received from server */
40 	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
41 	NFS_LSEG_LAYOUTRETURN,	/* layoutreturn bit set for layoutreturn */
42 };
43 
44 /* Individual ip address */
45 struct nfs4_pnfs_ds_addr {
46 	struct sockaddr_storage	da_addr;
47 	size_t			da_addrlen;
48 	struct list_head	da_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
49 	char			*da_remotestr;	/* human readable addr+port */
50 };
51 
52 struct nfs4_pnfs_ds {
53 	struct list_head	ds_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
54 	char			*ds_remotestr;	/* comma sep list of addrs */
55 	struct list_head	ds_addrs;
56 	struct nfs_client	*ds_clp;
57 	atomic_t		ds_count;
58 	unsigned long		ds_state;
59 #define NFS4DS_CONNECTING	0	/* ds is establishing connection */
60 };
61 
62 struct pnfs_layout_segment {
63 	struct list_head pls_list;
64 	struct list_head pls_lc_list;
65 	struct pnfs_layout_range pls_range;
66 	atomic_t pls_refcount;
67 	unsigned long pls_flags;
68 	struct pnfs_layout_hdr *pls_layout;
69 	struct work_struct pls_work;
70 };
71 
72 enum pnfs_try_status {
73 	PNFS_ATTEMPTED     = 0,
74 	PNFS_NOT_ATTEMPTED = 1,
75 	PNFS_TRY_AGAIN     = 2,
76 };
77 
78 #ifdef CONFIG_NFS_V4_1
79 
80 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
81 
82 /*
83  * Default data server connection timeout and retrans vaules.
84  * Set by module parameters dataserver_timeo and dataserver_retrans.
85  */
86 #define NFS4_DEF_DS_TIMEO   600 /* in tenths of a second */
87 #define NFS4_DEF_DS_RETRANS 5
88 
89 /* error codes for internal use */
90 #define NFS4ERR_RESET_TO_MDS   12001
91 #define NFS4ERR_RESET_TO_PNFS  12002
92 
93 enum {
94 	NFS_LAYOUT_RO_FAILED = 0,	/* get ro layout failed stop trying */
95 	NFS_LAYOUT_RW_FAILED,		/* get rw layout failed stop trying */
96 	NFS_LAYOUT_BULK_RECALL,		/* bulk recall affecting layout */
97 	NFS_LAYOUT_ROC,			/* some lseg had roc bit set */
98 	NFS_LAYOUT_RETURN,		/* Return this layout ASAP */
99 	NFS_LAYOUT_RETURN_BEFORE_CLOSE,	/* Return this layout before close */
100 	NFS_LAYOUT_INVALID_STID,	/* layout stateid id is invalid */
101 	NFS_LAYOUT_FIRST_LAYOUTGET,	/* Serialize first layoutget */
102 	NFS_LAYOUT_RETRY_LAYOUTGET,	/* Retry layoutget */
103 };
104 
105 enum layoutdriver_policy_flags {
106 	/* Should the pNFS client commit and return the layout upon truncate to
107 	 * a smaller size */
108 	PNFS_LAYOUTRET_ON_SETATTR	= 1 << 0,
109 	PNFS_LAYOUTRET_ON_ERROR		= 1 << 1,
110 	PNFS_READ_WHOLE_PAGE		= 1 << 2,
111 };
112 
113 struct nfs4_deviceid_node;
114 
115 /* Per-layout driver specific registration structure */
116 struct pnfs_layoutdriver_type {
117 	struct list_head pnfs_tblid;
118 	const u32 id;
119 	const char *name;
120 	struct module *owner;
121 	unsigned flags;
122 	unsigned max_deviceinfo_size;
123 
124 	int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
125 	int (*clear_layoutdriver) (struct nfs_server *);
126 
127 	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
128 	void (*free_layout_hdr) (struct pnfs_layout_hdr *);
129 
130 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
131 	void (*free_lseg) (struct pnfs_layout_segment *lseg);
132 
133 	void (*return_range) (struct pnfs_layout_hdr *lo,
134 			      struct pnfs_layout_range *range);
135 
136 	/* test for nfs page cache coalescing */
137 	const struct nfs_pageio_ops *pg_read_ops;
138 	const struct nfs_pageio_ops *pg_write_ops;
139 
140 	struct pnfs_ds_commit_info *(*get_ds_info) (struct inode *inode);
141 	void (*mark_request_commit) (struct nfs_page *req,
142 				     struct pnfs_layout_segment *lseg,
143 				     struct nfs_commit_info *cinfo,
144 				     u32 ds_commit_idx);
145 	void (*clear_request_commit) (struct nfs_page *req,
146 				      struct nfs_commit_info *cinfo);
147 	int (*scan_commit_lists) (struct nfs_commit_info *cinfo,
148 				  int max);
149 	void (*recover_commit_reqs) (struct list_head *list,
150 				     struct nfs_commit_info *cinfo);
151 	struct nfs_page * (*search_commit_reqs)(struct nfs_commit_info *cinfo,
152 						struct page *page);
153 	int (*commit_pagelist)(struct inode *inode,
154 			       struct list_head *mds_pages,
155 			       int how,
156 			       struct nfs_commit_info *cinfo);
157 
158 	/*
159 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
160 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
161 	 */
162 	enum pnfs_try_status (*read_pagelist)(struct nfs_pgio_header *);
163 	enum pnfs_try_status (*write_pagelist)(struct nfs_pgio_header *, int);
164 
165 	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
166 	struct nfs4_deviceid_node * (*alloc_deviceid_node)
167 			(struct nfs_server *server, struct pnfs_device *pdev,
168 			gfp_t gfp_flags);
169 
170 	void (*encode_layoutreturn) (struct pnfs_layout_hdr *layoutid,
171 				     struct xdr_stream *xdr,
172 				     const struct nfs4_layoutreturn_args *args);
173 
174 	void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
175 	int (*prepare_layoutcommit) (struct nfs4_layoutcommit_args *args);
176 	void (*encode_layoutcommit) (struct pnfs_layout_hdr *lo,
177 				     struct xdr_stream *xdr,
178 				     const struct nfs4_layoutcommit_args *args);
179 };
180 
181 struct pnfs_layout_hdr {
182 	atomic_t		plh_refcount;
183 	struct list_head	plh_layouts;   /* other client layouts */
184 	struct list_head	plh_bulk_destroy;
185 	struct list_head	plh_segs;      /* layout segments list */
186 	nfs4_stateid		plh_stateid;
187 	atomic_t		plh_outstanding; /* number of RPCs out */
188 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
189 	u32			plh_barrier; /* ignore lower seqids */
190 	unsigned long		plh_retry_timestamp;
191 	unsigned long		plh_flags;
192 	enum pnfs_iomode	plh_return_iomode;
193 	loff_t			plh_lwb; /* last write byte for layoutcommit */
194 	struct rpc_cred		*plh_lc_cred; /* layoutcommit cred */
195 	struct inode		*plh_inode;
196 };
197 
198 struct pnfs_device {
199 	struct nfs4_deviceid dev_id;
200 	unsigned int  layout_type;
201 	unsigned int  mincount;
202 	unsigned int  maxcount;	/* gdia_maxcount */
203 	struct page **pages;
204 	unsigned int  pgbase;
205 	unsigned int  pglen;	/* reply buffer length */
206 };
207 
208 #define NFS4_PNFS_GETDEVLIST_MAXNUM 16
209 
210 struct pnfs_devicelist {
211 	unsigned int		eof;
212 	unsigned int		num_devs;
213 	struct nfs4_deviceid	dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
214 };
215 
216 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
217 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
218 
219 /* nfs4proc.c */
220 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
221 				   struct pnfs_device *dev,
222 				   struct rpc_cred *cred);
223 extern struct pnfs_layout_segment* nfs4_proc_layoutget(struct nfs4_layoutget *lgp, gfp_t gfp_flags);
224 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp, bool sync);
225 
226 /* pnfs.c */
227 void pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo);
228 void pnfs_put_lseg(struct pnfs_layout_segment *lseg);
229 void pnfs_put_lseg_locked(struct pnfs_layout_segment *lseg);
230 
231 void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, u32);
232 void unset_pnfs_layoutdriver(struct nfs_server *);
233 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
234 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
235 void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
236 			        struct nfs_page *req, u64 wb_size);
237 void pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *);
238 int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
239 size_t pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
240 			    struct nfs_page *prev, struct nfs_page *req);
241 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg);
242 struct pnfs_layout_segment *pnfs_layout_process(struct nfs4_layoutget *lgp);
243 void pnfs_free_lseg_list(struct list_head *tmp_list);
244 void pnfs_destroy_layout(struct nfs_inode *);
245 void pnfs_destroy_all_layouts(struct nfs_client *);
246 int pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
247 		struct nfs_fsid *fsid,
248 		bool is_recall);
249 int pnfs_destroy_layouts_byclid(struct nfs_client *clp,
250 		bool is_recall);
251 void pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo);
252 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
253 			     const nfs4_stateid *new,
254 			     bool update_barrier);
255 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
256 				  struct pnfs_layout_hdr *lo,
257 				  struct pnfs_layout_range *range,
258 				  struct nfs4_state *open_state);
259 int pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
260 				struct list_head *tmp_list,
261 				struct pnfs_layout_range *recall_range);
262 bool pnfs_roc(struct inode *ino);
263 void pnfs_roc_release(struct inode *ino);
264 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
265 bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task);
266 void pnfs_set_layoutcommit(struct nfs_pgio_header *);
267 void pnfs_commit_set_layoutcommit(struct nfs_commit_data *data);
268 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
269 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
270 int _pnfs_return_layout(struct inode *);
271 int pnfs_commit_and_return_layout(struct inode *);
272 void pnfs_ld_write_done(struct nfs_pgio_header *);
273 void pnfs_ld_read_done(struct nfs_pgio_header *);
274 int pnfs_read_resend_pnfs(struct nfs_pgio_header *);
275 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
276 					       struct nfs_open_context *ctx,
277 					       loff_t pos,
278 					       u64 count,
279 					       enum pnfs_iomode iomode,
280 					       gfp_t gfp_flags);
281 void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo);
282 
283 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
284 int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *);
285 int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *);
286 struct nfs4_threshold *pnfs_mdsthreshold_alloc(void);
287 void pnfs_error_mark_layout_for_return(struct inode *inode,
288 				       struct pnfs_layout_segment *lseg);
289 
290 /* nfs4_deviceid_flags */
291 enum {
292 	NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
293 	NFS_DEVICEID_UNAVAILABLE,	/* device temporarily unavailable */
294 };
295 
296 /* pnfs_dev.c */
297 struct nfs4_deviceid_node {
298 	struct hlist_node		node;
299 	struct hlist_node		tmpnode;
300 	const struct pnfs_layoutdriver_type *ld;
301 	const struct nfs_client		*nfs_client;
302 	unsigned long 			flags;
303 	unsigned long			timestamp_unavailable;
304 	struct nfs4_deviceid		deviceid;
305 	atomic_t			ref;
306 };
307 
308 struct nfs4_deviceid_node *
309 nfs4_find_get_deviceid(struct nfs_server *server,
310 		const struct nfs4_deviceid *id, struct rpc_cred *cred,
311 		gfp_t gfp_mask);
312 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
313 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *, struct nfs_server *,
314 			     const struct nfs4_deviceid *);
315 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
316 void nfs4_mark_deviceid_unavailable(struct nfs4_deviceid_node *node);
317 bool nfs4_test_deviceid_unavailable(struct nfs4_deviceid_node *node);
318 void nfs4_deviceid_purge_client(const struct nfs_client *);
319 
320 /* pnfs_nfs.c */
321 void pnfs_generic_clear_request_commit(struct nfs_page *req,
322 				       struct nfs_commit_info *cinfo);
323 void pnfs_generic_commit_release(void *calldata);
324 void pnfs_generic_prepare_to_resend_writes(struct nfs_commit_data *data);
325 void pnfs_generic_rw_release(void *data);
326 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
327 				      struct nfs_commit_info *cinfo);
328 int pnfs_generic_commit_pagelist(struct inode *inode,
329 				 struct list_head *mds_pages,
330 				 int how,
331 				 struct nfs_commit_info *cinfo,
332 				 int (*initiate_commit)(struct nfs_commit_data *data,
333 							int how));
334 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo, int max);
335 void pnfs_generic_write_commit_done(struct rpc_task *task, void *data);
336 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds);
337 struct nfs4_pnfs_ds *nfs4_pnfs_ds_add(struct list_head *dsaddrs,
338 				      gfp_t gfp_flags);
339 void nfs4_pnfs_v3_ds_connect_unload(void);
340 void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
341 			  struct nfs4_deviceid_node *devid, unsigned int timeo,
342 			  unsigned int retrans, u32 version, u32 minor_version,
343 			  rpc_authflavor_t au_flavor);
344 struct nfs4_pnfs_ds_addr *nfs4_decode_mp_ds_addr(struct net *net,
345 						 struct xdr_stream *xdr,
346 						 gfp_t gfp_flags);
347 void pnfs_layout_mark_request_commit(struct nfs_page *req,
348 				     struct pnfs_layout_segment *lseg,
349 				     struct nfs_commit_info *cinfo,
350 				     u32 ds_commit_idx);
351 
352 static inline bool nfs_have_layout(struct inode *inode)
353 {
354 	return NFS_I(inode)->layout != NULL;
355 }
356 
357 static inline struct nfs4_deviceid_node *
358 nfs4_get_deviceid(struct nfs4_deviceid_node *d)
359 {
360 	atomic_inc(&d->ref);
361 	return d;
362 }
363 
364 static inline void pnfs_set_retry_layoutget(struct pnfs_layout_hdr *lo)
365 {
366 	if (!test_and_set_bit(NFS_LAYOUT_RETRY_LAYOUTGET, &lo->plh_flags))
367 		atomic_inc(&lo->plh_refcount);
368 }
369 
370 static inline void pnfs_clear_retry_layoutget(struct pnfs_layout_hdr *lo)
371 {
372 	if (test_and_clear_bit(NFS_LAYOUT_RETRY_LAYOUTGET, &lo->plh_flags)) {
373 		atomic_dec(&lo->plh_refcount);
374 		/* wake up waiters for LAYOUTRETURN as that is not needed */
375 		wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
376 	}
377 }
378 
379 static inline bool pnfs_should_retry_layoutget(struct pnfs_layout_hdr *lo)
380 {
381 	return test_bit(NFS_LAYOUT_RETRY_LAYOUTGET, &lo->plh_flags);
382 }
383 
384 static inline struct pnfs_layout_segment *
385 pnfs_get_lseg(struct pnfs_layout_segment *lseg)
386 {
387 	if (lseg) {
388 		atomic_inc(&lseg->pls_refcount);
389 		smp_mb__after_atomic();
390 	}
391 	return lseg;
392 }
393 
394 /* Return true if a layout driver is being used for this mountpoint */
395 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
396 {
397 	return nfss->pnfs_curr_ld != NULL;
398 }
399 
400 static inline int
401 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how,
402 		 struct nfs_commit_info *cinfo)
403 {
404 	if (cinfo->ds == NULL || cinfo->ds->ncommitting == 0)
405 		return PNFS_NOT_ATTEMPTED;
406 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how, cinfo);
407 }
408 
409 static inline struct pnfs_ds_commit_info *
410 pnfs_get_ds_info(struct inode *inode)
411 {
412 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
413 
414 	if (ld == NULL || ld->get_ds_info == NULL)
415 		return NULL;
416 	return ld->get_ds_info(inode);
417 }
418 
419 static inline void
420 pnfs_generic_mark_devid_invalid(struct nfs4_deviceid_node *node)
421 {
422 	set_bit(NFS_DEVICEID_INVALID, &node->flags);
423 }
424 
425 static inline bool
426 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
427 			 struct nfs_commit_info *cinfo, u32 ds_commit_idx)
428 {
429 	struct inode *inode = req->wb_context->dentry->d_inode;
430 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
431 
432 	if (lseg == NULL || ld->mark_request_commit == NULL)
433 		return false;
434 	ld->mark_request_commit(req, lseg, cinfo, ds_commit_idx);
435 	return true;
436 }
437 
438 static inline bool
439 pnfs_clear_request_commit(struct nfs_page *req, struct nfs_commit_info *cinfo)
440 {
441 	struct inode *inode = req->wb_context->dentry->d_inode;
442 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
443 
444 	if (ld == NULL || ld->clear_request_commit == NULL)
445 		return false;
446 	ld->clear_request_commit(req, cinfo);
447 	return true;
448 }
449 
450 static inline int
451 pnfs_scan_commit_lists(struct inode *inode, struct nfs_commit_info *cinfo,
452 		       int max)
453 {
454 	if (cinfo->ds == NULL || cinfo->ds->nwritten == 0)
455 		return 0;
456 	else
457 		return NFS_SERVER(inode)->pnfs_curr_ld->scan_commit_lists(cinfo, max);
458 }
459 
460 static inline struct nfs_page *
461 pnfs_search_commit_reqs(struct inode *inode, struct nfs_commit_info *cinfo,
462 			struct page *page)
463 {
464 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
465 
466 	if (ld == NULL || ld->search_commit_reqs == NULL)
467 		return NULL;
468 	return ld->search_commit_reqs(cinfo, page);
469 }
470 
471 /* Should the pNFS client commit and return the layout upon a setattr */
472 static inline bool
473 pnfs_ld_layoutret_on_setattr(struct inode *inode)
474 {
475 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
476 		return false;
477 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
478 		PNFS_LAYOUTRET_ON_SETATTR;
479 }
480 
481 static inline bool
482 pnfs_ld_read_whole_page(struct inode *inode)
483 {
484 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
485 		return false;
486 	return NFS_SERVER(inode)->pnfs_curr_ld->flags & PNFS_READ_WHOLE_PAGE;
487 }
488 
489 static inline bool
490 pnfs_layoutcommit_outstanding(struct inode *inode)
491 {
492 	struct nfs_inode *nfsi = NFS_I(inode);
493 
494 	return test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags) != 0 ||
495 		test_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags) != 0;
496 }
497 
498 static inline int pnfs_return_layout(struct inode *ino)
499 {
500 	struct nfs_inode *nfsi = NFS_I(ino);
501 	struct nfs_server *nfss = NFS_SERVER(ino);
502 
503 	if (pnfs_enabled_sb(nfss) && nfsi->layout)
504 		return _pnfs_return_layout(ino);
505 
506 	return 0;
507 }
508 
509 static inline bool
510 pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
511 		   struct nfs_server *nfss)
512 {
513 	return (dst && src && src->bm != 0 && nfss->pnfs_curr_ld &&
514 					nfss->pnfs_curr_ld->id == src->l_type);
515 }
516 
517 #ifdef NFS_DEBUG
518 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
519 #else
520 static inline void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id)
521 {
522 }
523 #endif /* NFS_DEBUG */
524 #else  /* CONFIG_NFS_V4_1 */
525 
526 static inline bool nfs_have_layout(struct inode *inode)
527 {
528 	return false;
529 }
530 
531 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
532 {
533 }
534 
535 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
536 {
537 }
538 
539 static inline struct pnfs_layout_segment *
540 pnfs_get_lseg(struct pnfs_layout_segment *lseg)
541 {
542 	return NULL;
543 }
544 
545 static inline void pnfs_put_lseg(struct pnfs_layout_segment *lseg)
546 {
547 }
548 
549 static inline int pnfs_return_layout(struct inode *ino)
550 {
551 	return 0;
552 }
553 
554 static inline int pnfs_commit_and_return_layout(struct inode *inode)
555 {
556 	return 0;
557 }
558 
559 static inline bool
560 pnfs_ld_layoutret_on_setattr(struct inode *inode)
561 {
562 	return false;
563 }
564 
565 static inline bool
566 pnfs_ld_read_whole_page(struct inode *inode)
567 {
568 	return false;
569 }
570 
571 static inline bool
572 pnfs_roc(struct inode *ino)
573 {
574 	return false;
575 }
576 
577 static inline void
578 pnfs_roc_release(struct inode *ino)
579 {
580 }
581 
582 static inline void
583 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
584 {
585 }
586 
587 static inline bool
588 pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
589 {
590 	return false;
591 }
592 
593 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
594 					 const struct nfs_fh *mntfh, u32 id)
595 {
596 }
597 
598 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
599 {
600 }
601 
602 static inline int
603 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how,
604 		 struct nfs_commit_info *cinfo)
605 {
606 	return PNFS_NOT_ATTEMPTED;
607 }
608 
609 static inline struct pnfs_ds_commit_info *
610 pnfs_get_ds_info(struct inode *inode)
611 {
612 	return NULL;
613 }
614 
615 static inline bool
616 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
617 			 struct nfs_commit_info *cinfo, u32 ds_commit_idx)
618 {
619 	return false;
620 }
621 
622 static inline bool
623 pnfs_clear_request_commit(struct nfs_page *req, struct nfs_commit_info *cinfo)
624 {
625 	return false;
626 }
627 
628 static inline int
629 pnfs_scan_commit_lists(struct inode *inode, struct nfs_commit_info *cinfo,
630 		       int max)
631 {
632 	return 0;
633 }
634 
635 static inline struct nfs_page *
636 pnfs_search_commit_reqs(struct inode *inode, struct nfs_commit_info *cinfo,
637 			struct page *page)
638 {
639 	return NULL;
640 }
641 
642 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
643 {
644 	return 0;
645 }
646 
647 static inline bool
648 pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
649 		   struct nfs_server *nfss)
650 {
651 	return false;
652 }
653 
654 static inline bool
655 pnfs_layoutcommit_outstanding(struct inode *inode)
656 {
657 	return false;
658 }
659 
660 
661 static inline struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
662 {
663 	return NULL;
664 }
665 
666 static inline void nfs4_pnfs_v3_ds_connect_unload(void)
667 {
668 }
669 
670 #endif /* CONFIG_NFS_V4_1 */
671 
672 #endif /* FS_NFS_PNFS_H */
673