xref: /openbmc/linux/fs/nfs/pnfs.h (revision 50df3be7)
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/refcount.h>
34 #include <linux/nfs_fs.h>
35 #include <linux/nfs_page.h>
36 #include <linux/workqueue.h>
37 
38 struct nfs4_opendata;
39 
40 enum {
41 	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
42 	NFS_LSEG_ROC,		/* roc bit received from server */
43 	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
44 	NFS_LSEG_LAYOUTRETURN,	/* layoutreturn bit set for layoutreturn */
45 	NFS_LSEG_UNAVAILABLE,	/* unavailable bit set for temporary problem */
46 };
47 
48 /* Individual ip address */
49 struct nfs4_pnfs_ds_addr {
50 	struct sockaddr_storage	da_addr;
51 	size_t			da_addrlen;
52 	struct list_head	da_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
53 	char			*da_remotestr;	/* human readable addr+port */
54 };
55 
56 struct nfs4_pnfs_ds {
57 	struct list_head	ds_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
58 	char			*ds_remotestr;	/* comma sep list of addrs */
59 	struct list_head	ds_addrs;
60 	struct nfs_client	*ds_clp;
61 	refcount_t		ds_count;
62 	unsigned long		ds_state;
63 #define NFS4DS_CONNECTING	0	/* ds is establishing connection */
64 };
65 
66 struct pnfs_layout_segment {
67 	struct list_head pls_list;
68 	struct list_head pls_lc_list;
69 	struct pnfs_layout_range pls_range;
70 	refcount_t pls_refcount;
71 	u32 pls_seq;
72 	unsigned long pls_flags;
73 	struct pnfs_layout_hdr *pls_layout;
74 };
75 
76 enum pnfs_try_status {
77 	PNFS_ATTEMPTED     = 0,
78 	PNFS_NOT_ATTEMPTED = 1,
79 	PNFS_TRY_AGAIN     = 2,
80 };
81 
82 #ifdef CONFIG_NFS_V4_1
83 
84 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
85 
86 /*
87  * Default data server connection timeout and retrans vaules.
88  * Set by module parameters dataserver_timeo and dataserver_retrans.
89  */
90 #define NFS4_DEF_DS_TIMEO   600 /* in tenths of a second */
91 #define NFS4_DEF_DS_RETRANS 5
92 #define PNFS_DEVICE_RETRY_TIMEOUT (120*HZ)
93 
94 /* error codes for internal use */
95 #define NFS4ERR_RESET_TO_MDS   12001
96 #define NFS4ERR_RESET_TO_PNFS  12002
97 
98 enum {
99 	NFS_LAYOUT_RO_FAILED = 0,	/* get ro layout failed stop trying */
100 	NFS_LAYOUT_RW_FAILED,		/* get rw layout failed stop trying */
101 	NFS_LAYOUT_BULK_RECALL,		/* bulk recall affecting layout */
102 	NFS_LAYOUT_RETURN,		/* layoutreturn in progress */
103 	NFS_LAYOUT_RETURN_LOCK,		/* Serialise layoutreturn */
104 	NFS_LAYOUT_RETURN_REQUESTED,	/* Return this layout ASAP */
105 	NFS_LAYOUT_INVALID_STID,	/* layout stateid id is invalid */
106 	NFS_LAYOUT_FIRST_LAYOUTGET,	/* Serialize first layoutget */
107 	NFS_LAYOUT_INODE_FREEING,	/* The inode is being freed */
108 };
109 
110 enum layoutdriver_policy_flags {
111 	/* Should the pNFS client commit and return the layout upon truncate to
112 	 * a smaller size */
113 	PNFS_LAYOUTRET_ON_SETATTR	= 1 << 0,
114 	PNFS_LAYOUTRET_ON_ERROR		= 1 << 1,
115 	PNFS_READ_WHOLE_PAGE		= 1 << 2,
116 	PNFS_LAYOUTGET_ON_OPEN		= 1 << 3,
117 };
118 
119 struct nfs4_deviceid_node;
120 
121 /* Per-layout driver specific registration structure */
122 struct pnfs_layoutdriver_type {
123 	struct list_head pnfs_tblid;
124 	const u32 id;
125 	const char *name;
126 	struct module *owner;
127 	unsigned flags;
128 	unsigned max_deviceinfo_size;
129 	unsigned max_layoutget_response;
130 
131 	int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
132 	int (*clear_layoutdriver) (struct nfs_server *);
133 
134 	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
135 	void (*free_layout_hdr) (struct pnfs_layout_hdr *);
136 
137 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
138 	void (*free_lseg) (struct pnfs_layout_segment *lseg);
139 	void (*add_lseg) (struct pnfs_layout_hdr *layoutid,
140 			struct pnfs_layout_segment *lseg,
141 			struct list_head *free_me);
142 
143 	void (*return_range) (struct pnfs_layout_hdr *lo,
144 			      struct pnfs_layout_range *range);
145 
146 	/* test for nfs page cache coalescing */
147 	const struct nfs_pageio_ops *pg_read_ops;
148 	const struct nfs_pageio_ops *pg_write_ops;
149 
150 	struct pnfs_ds_commit_info *(*get_ds_info) (struct inode *inode);
151 	void (*mark_request_commit) (struct nfs_page *req,
152 				     struct pnfs_layout_segment *lseg,
153 				     struct nfs_commit_info *cinfo,
154 				     u32 ds_commit_idx);
155 	void (*clear_request_commit) (struct nfs_page *req,
156 				      struct nfs_commit_info *cinfo);
157 	int (*scan_commit_lists) (struct nfs_commit_info *cinfo,
158 				  int max);
159 	void (*recover_commit_reqs) (struct list_head *list,
160 				     struct nfs_commit_info *cinfo);
161 	struct nfs_page * (*search_commit_reqs)(struct nfs_commit_info *cinfo,
162 						struct page *page);
163 	int (*commit_pagelist)(struct inode *inode,
164 			       struct list_head *mds_pages,
165 			       int how,
166 			       struct nfs_commit_info *cinfo);
167 
168 	int (*sync)(struct inode *inode, bool datasync);
169 
170 	/*
171 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
172 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
173 	 */
174 	enum pnfs_try_status (*read_pagelist)(struct nfs_pgio_header *);
175 	enum pnfs_try_status (*write_pagelist)(struct nfs_pgio_header *, int);
176 
177 	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
178 	struct nfs4_deviceid_node * (*alloc_deviceid_node)
179 			(struct nfs_server *server, struct pnfs_device *pdev,
180 			gfp_t gfp_flags);
181 
182 	int (*prepare_layoutreturn) (struct nfs4_layoutreturn_args *);
183 
184 	void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
185 	int (*prepare_layoutcommit) (struct nfs4_layoutcommit_args *args);
186 	int (*prepare_layoutstats) (struct nfs42_layoutstat_args *args);
187 };
188 
189 struct pnfs_layout_hdr {
190 	refcount_t		plh_refcount;
191 	atomic_t		plh_outstanding; /* number of RPCs out */
192 	struct list_head	plh_layouts;   /* other client layouts */
193 	struct list_head	plh_bulk_destroy;
194 	struct list_head	plh_segs;      /* layout segments list */
195 	struct list_head	plh_return_segs; /* invalid layout segments */
196 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
197 	unsigned long		plh_retry_timestamp;
198 	unsigned long		plh_flags;
199 	nfs4_stateid		plh_stateid;
200 	u32			plh_barrier; /* ignore lower seqids */
201 	u32			plh_return_seq;
202 	enum pnfs_iomode	plh_return_iomode;
203 	loff_t			plh_lwb; /* last write byte for layoutcommit */
204 	const struct cred	*plh_lc_cred; /* layoutcommit cred */
205 	struct inode		*plh_inode;
206 };
207 
208 struct pnfs_device {
209 	struct nfs4_deviceid dev_id;
210 	unsigned int  layout_type;
211 	unsigned int  mincount;
212 	unsigned int  maxcount;	/* gdia_maxcount */
213 	struct page **pages;
214 	unsigned int  pgbase;
215 	unsigned int  pglen;	/* reply buffer length */
216 	unsigned char nocache : 1;/* May not be cached */
217 };
218 
219 #define NFS4_PNFS_GETDEVLIST_MAXNUM 16
220 
221 struct pnfs_devicelist {
222 	unsigned int		eof;
223 	unsigned int		num_devs;
224 	struct nfs4_deviceid	dev_id[NFS4_PNFS_GETDEVLIST_MAXNUM];
225 };
226 
227 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
228 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
229 
230 /* nfs4proc.c */
231 extern size_t max_response_pages(struct nfs_server *server);
232 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
233 				   struct pnfs_device *dev,
234 				   const struct cred *cred);
235 extern struct pnfs_layout_segment* nfs4_proc_layoutget(struct nfs4_layoutget *lgp, long *timeout);
236 extern int nfs4_proc_layoutreturn(struct nfs4_layoutreturn *lrp, bool sync);
237 
238 /* pnfs.c */
239 void pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo);
240 void pnfs_put_lseg(struct pnfs_layout_segment *lseg);
241 
242 void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, struct nfs_fsinfo *);
243 void unset_pnfs_layoutdriver(struct nfs_server *);
244 void pnfs_generic_pg_check_layout(struct nfs_pageio_descriptor *pgio);
245 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
246 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
247 void pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
248 			        struct nfs_page *req, u64 wb_size);
249 void pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *);
250 int pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
251 size_t pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
252 			    struct nfs_page *prev, struct nfs_page *req);
253 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg);
254 struct pnfs_layout_segment *pnfs_layout_process(struct nfs4_layoutget *lgp);
255 void pnfs_layoutget_free(struct nfs4_layoutget *lgp);
256 void pnfs_free_lseg_list(struct list_head *tmp_list);
257 void pnfs_destroy_layout(struct nfs_inode *);
258 void pnfs_destroy_all_layouts(struct nfs_client *);
259 int pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
260 		struct nfs_fsid *fsid,
261 		bool is_recall);
262 int pnfs_destroy_layouts_byclid(struct nfs_client *clp,
263 		bool is_recall);
264 bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
265 		struct pnfs_layout_range *dst_range,
266 		struct inode *inode);
267 void pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo);
268 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
269 			     const nfs4_stateid *new,
270 			     bool update_barrier);
271 int pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
272 				struct list_head *tmp_list,
273 				const struct pnfs_layout_range *recall_range,
274 				u32 seq);
275 int pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
276 				struct list_head *tmp_list,
277 				const struct pnfs_layout_range *recall_range,
278 				u32 seq);
279 int pnfs_mark_layout_stateid_invalid(struct pnfs_layout_hdr *lo,
280 		struct list_head *lseg_list);
281 bool pnfs_roc(struct inode *ino,
282 		struct nfs4_layoutreturn_args *args,
283 		struct nfs4_layoutreturn_res *res,
284 		const struct cred *cred);
285 int pnfs_roc_done(struct rpc_task *task, struct inode *inode,
286 		struct nfs4_layoutreturn_args **argpp,
287 		struct nfs4_layoutreturn_res **respp,
288 		int *ret);
289 void pnfs_roc_release(struct nfs4_layoutreturn_args *args,
290 		struct nfs4_layoutreturn_res *res,
291 		int ret);
292 bool pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task);
293 void pnfs_set_layoutcommit(struct inode *, struct pnfs_layout_segment *, loff_t);
294 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data);
295 int pnfs_layoutcommit_inode(struct inode *inode, bool sync);
296 int pnfs_generic_sync(struct inode *inode, bool datasync);
297 int pnfs_nfs_generic_sync(struct inode *inode, bool datasync);
298 int _pnfs_return_layout(struct inode *);
299 int pnfs_commit_and_return_layout(struct inode *);
300 void pnfs_ld_write_done(struct nfs_pgio_header *);
301 void pnfs_ld_read_done(struct nfs_pgio_header *);
302 void pnfs_read_resend_pnfs(struct nfs_pgio_header *);
303 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
304 					       struct nfs_open_context *ctx,
305 					       loff_t pos,
306 					       u64 count,
307 					       enum pnfs_iomode iomode,
308 					       bool strict_iomode,
309 					       gfp_t gfp_flags);
310 void pnfs_layoutreturn_free_lsegs(struct pnfs_layout_hdr *lo,
311 		const nfs4_stateid *arg_stateid,
312 		const struct pnfs_layout_range *range,
313 		const nfs4_stateid *stateid);
314 
315 void pnfs_generic_layout_insert_lseg(struct pnfs_layout_hdr *lo,
316 		   struct pnfs_layout_segment *lseg,
317 		   bool (*is_after)(const struct pnfs_layout_range *lseg_range,
318 			   const struct pnfs_layout_range *old),
319 		   bool (*do_merge)(struct pnfs_layout_segment *lseg,
320 			   struct pnfs_layout_segment *old),
321 		   struct list_head *free_me);
322 
323 void nfs4_deviceid_mark_client_invalid(struct nfs_client *clp);
324 int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *);
325 int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *);
326 struct nfs4_threshold *pnfs_mdsthreshold_alloc(void);
327 void pnfs_error_mark_layout_for_return(struct inode *inode,
328 				       struct pnfs_layout_segment *lseg);
329 /* nfs4_deviceid_flags */
330 enum {
331 	NFS_DEVICEID_INVALID = 0,       /* set when MDS clientid recalled */
332 	NFS_DEVICEID_UNAVAILABLE,	/* device temporarily unavailable */
333 	NFS_DEVICEID_NOCACHE,		/* device may not be cached */
334 };
335 
336 /* pnfs_dev.c */
337 struct nfs4_deviceid_node {
338 	struct hlist_node		node;
339 	struct hlist_node		tmpnode;
340 	const struct pnfs_layoutdriver_type *ld;
341 	const struct nfs_client		*nfs_client;
342 	unsigned long 			flags;
343 	unsigned long			timestamp_unavailable;
344 	struct nfs4_deviceid		deviceid;
345 	struct rcu_head			rcu;
346 	atomic_t			ref;
347 };
348 
349 struct nfs4_deviceid_node *
350 nfs4_find_get_deviceid(struct nfs_server *server,
351 		const struct nfs4_deviceid *id, const struct cred *cred,
352 		gfp_t gfp_mask);
353 void nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *, const struct nfs_client *, const struct nfs4_deviceid *);
354 void nfs4_init_deviceid_node(struct nfs4_deviceid_node *, struct nfs_server *,
355 			     const struct nfs4_deviceid *);
356 bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *);
357 void nfs4_mark_deviceid_available(struct nfs4_deviceid_node *node);
358 void nfs4_mark_deviceid_unavailable(struct nfs4_deviceid_node *node);
359 bool nfs4_test_deviceid_unavailable(struct nfs4_deviceid_node *node);
360 void nfs4_deviceid_purge_client(const struct nfs_client *);
361 
362 /* pnfs_nfs.c */
363 void pnfs_generic_clear_request_commit(struct nfs_page *req,
364 				       struct nfs_commit_info *cinfo);
365 void pnfs_generic_commit_release(void *calldata);
366 void pnfs_generic_prepare_to_resend_writes(struct nfs_commit_data *data);
367 void pnfs_generic_rw_release(void *data);
368 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
369 				      struct nfs_commit_info *cinfo);
370 int pnfs_generic_commit_pagelist(struct inode *inode,
371 				 struct list_head *mds_pages,
372 				 int how,
373 				 struct nfs_commit_info *cinfo,
374 				 int (*initiate_commit)(struct nfs_commit_data *data,
375 							int how));
376 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo, int max);
377 void pnfs_generic_write_commit_done(struct rpc_task *task, void *data);
378 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds);
379 struct nfs4_pnfs_ds *nfs4_pnfs_ds_add(struct list_head *dsaddrs,
380 				      gfp_t gfp_flags);
381 void nfs4_pnfs_v3_ds_connect_unload(void);
382 int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
383 			  struct nfs4_deviceid_node *devid, unsigned int timeo,
384 			  unsigned int retrans, u32 version, u32 minor_version);
385 struct nfs4_pnfs_ds_addr *nfs4_decode_mp_ds_addr(struct net *net,
386 						 struct xdr_stream *xdr,
387 						 gfp_t gfp_flags);
388 void pnfs_layout_mark_request_commit(struct nfs_page *req,
389 				     struct pnfs_layout_segment *lseg,
390 				     struct nfs_commit_info *cinfo,
391 				     u32 ds_commit_idx);
392 void pnfs_lgopen_prepare(struct nfs4_opendata *data,
393 			 struct nfs_open_context *ctx);
394 void pnfs_parse_lgopen(struct inode *ino, struct nfs4_layoutget *lgp,
395 		       struct nfs_open_context *ctx);
396 void nfs4_lgopen_release(struct nfs4_layoutget *lgp);
397 
398 static inline bool nfs_have_layout(struct inode *inode)
399 {
400 	return NFS_I(inode)->layout != NULL;
401 }
402 
403 static inline bool pnfs_layout_is_valid(const struct pnfs_layout_hdr *lo)
404 {
405 	return test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags) == 0;
406 }
407 
408 static inline struct nfs4_deviceid_node *
409 nfs4_get_deviceid(struct nfs4_deviceid_node *d)
410 {
411 	atomic_inc(&d->ref);
412 	return d;
413 }
414 
415 static inline struct pnfs_layout_segment *
416 pnfs_get_lseg(struct pnfs_layout_segment *lseg)
417 {
418 	if (lseg) {
419 		refcount_inc(&lseg->pls_refcount);
420 		smp_mb__after_atomic();
421 	}
422 	return lseg;
423 }
424 
425 static inline bool
426 pnfs_is_valid_lseg(struct pnfs_layout_segment *lseg)
427 {
428 	return test_bit(NFS_LSEG_VALID, &lseg->pls_flags) != 0;
429 }
430 
431 /* Return true if a layout driver is being used for this mountpoint */
432 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
433 {
434 	return nfss->pnfs_curr_ld != NULL;
435 }
436 
437 static inline int
438 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how,
439 		 struct nfs_commit_info *cinfo)
440 {
441 	if (cinfo->ds == NULL || cinfo->ds->ncommitting == 0)
442 		return PNFS_NOT_ATTEMPTED;
443 	return NFS_SERVER(inode)->pnfs_curr_ld->commit_pagelist(inode, mds_pages, how, cinfo);
444 }
445 
446 static inline struct pnfs_ds_commit_info *
447 pnfs_get_ds_info(struct inode *inode)
448 {
449 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
450 
451 	if (ld == NULL || ld->get_ds_info == NULL)
452 		return NULL;
453 	return ld->get_ds_info(inode);
454 }
455 
456 static inline void
457 pnfs_generic_mark_devid_invalid(struct nfs4_deviceid_node *node)
458 {
459 	set_bit(NFS_DEVICEID_INVALID, &node->flags);
460 }
461 
462 static inline bool
463 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
464 			 struct nfs_commit_info *cinfo, u32 ds_commit_idx)
465 {
466 	struct inode *inode = d_inode(nfs_req_openctx(req)->dentry);
467 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
468 
469 	if (lseg == NULL || ld->mark_request_commit == NULL)
470 		return false;
471 	ld->mark_request_commit(req, lseg, cinfo, ds_commit_idx);
472 	return true;
473 }
474 
475 static inline bool
476 pnfs_clear_request_commit(struct nfs_page *req, struct nfs_commit_info *cinfo)
477 {
478 	struct inode *inode = d_inode(nfs_req_openctx(req)->dentry);
479 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
480 
481 	if (ld == NULL || ld->clear_request_commit == NULL)
482 		return false;
483 	ld->clear_request_commit(req, cinfo);
484 	return true;
485 }
486 
487 static inline int
488 pnfs_scan_commit_lists(struct inode *inode, struct nfs_commit_info *cinfo,
489 		       int max)
490 {
491 	if (cinfo->ds == NULL || cinfo->ds->nwritten == 0)
492 		return 0;
493 	else
494 		return NFS_SERVER(inode)->pnfs_curr_ld->scan_commit_lists(cinfo, max);
495 }
496 
497 static inline struct nfs_page *
498 pnfs_search_commit_reqs(struct inode *inode, struct nfs_commit_info *cinfo,
499 			struct page *page)
500 {
501 	struct pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
502 
503 	if (ld == NULL || ld->search_commit_reqs == NULL)
504 		return NULL;
505 	return ld->search_commit_reqs(cinfo, page);
506 }
507 
508 /* Should the pNFS client commit and return the layout upon a setattr */
509 static inline bool
510 pnfs_ld_layoutret_on_setattr(struct inode *inode)
511 {
512 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
513 		return false;
514 	return NFS_SERVER(inode)->pnfs_curr_ld->flags &
515 		PNFS_LAYOUTRET_ON_SETATTR;
516 }
517 
518 static inline bool
519 pnfs_ld_read_whole_page(struct inode *inode)
520 {
521 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
522 		return false;
523 	return NFS_SERVER(inode)->pnfs_curr_ld->flags & PNFS_READ_WHOLE_PAGE;
524 }
525 
526 static inline int
527 pnfs_sync_inode(struct inode *inode, bool datasync)
528 {
529 	if (!pnfs_enabled_sb(NFS_SERVER(inode)))
530 		return 0;
531 	return NFS_SERVER(inode)->pnfs_curr_ld->sync(inode, datasync);
532 }
533 
534 static inline bool
535 pnfs_layoutcommit_outstanding(struct inode *inode)
536 {
537 	struct nfs_inode *nfsi = NFS_I(inode);
538 
539 	return test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags) != 0 ||
540 		test_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags) != 0;
541 }
542 
543 static inline int pnfs_return_layout(struct inode *ino)
544 {
545 	struct nfs_inode *nfsi = NFS_I(ino);
546 	struct nfs_server *nfss = NFS_SERVER(ino);
547 
548 	if (pnfs_enabled_sb(nfss) && nfsi->layout) {
549 		set_bit(NFS_LAYOUT_RETURN_REQUESTED, &nfsi->layout->plh_flags);
550 		return _pnfs_return_layout(ino);
551 	}
552 
553 	return 0;
554 }
555 
556 static inline bool
557 pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
558 		   struct nfs_server *nfss)
559 {
560 	return (dst && src && src->bm != 0 && nfss->pnfs_curr_ld &&
561 					nfss->pnfs_curr_ld->id == src->l_type);
562 }
563 
564 static inline u64
565 pnfs_calc_offset_end(u64 offset, u64 len)
566 {
567 	if (len == NFS4_MAX_UINT64 || len >= NFS4_MAX_UINT64 - offset)
568 		return NFS4_MAX_UINT64;
569 	return offset + len - 1;
570 }
571 
572 static inline u64
573 pnfs_calc_offset_length(u64 offset, u64 end)
574 {
575 	if (end == NFS4_MAX_UINT64 || end <= offset)
576 		return NFS4_MAX_UINT64;
577 	return 1 + end - offset;
578 }
579 
580 static inline void
581 pnfs_copy_range(struct pnfs_layout_range *dst,
582 		const struct pnfs_layout_range *src)
583 {
584 	memcpy(dst, src, sizeof(*dst));
585 }
586 
587 static inline u64
588 pnfs_end_offset(u64 start, u64 len)
589 {
590 	if (NFS4_MAX_UINT64 - start <= len)
591 		return NFS4_MAX_UINT64;
592 	return start + len;
593 }
594 
595 /*
596  * Are 2 ranges intersecting?
597  *   start1                             end1
598  *   [----------------------------------)
599  *                                start2           end2
600  *                                [----------------)
601  */
602 static inline bool
603 pnfs_is_range_intersecting(u64 start1, u64 end1, u64 start2, u64 end2)
604 {
605 	return (end1 == NFS4_MAX_UINT64 || start2 < end1) &&
606 		(end2 == NFS4_MAX_UINT64 || start1 < end2);
607 }
608 
609 static inline bool
610 pnfs_lseg_range_intersecting(const struct pnfs_layout_range *l1,
611 		const struct pnfs_layout_range *l2)
612 {
613 	u64 end1 = pnfs_end_offset(l1->offset, l1->length);
614 	u64 end2 = pnfs_end_offset(l2->offset, l2->length);
615 
616 	return pnfs_is_range_intersecting(l1->offset, end1, l2->offset, end2);
617 }
618 
619 static inline bool
620 pnfs_lseg_request_intersecting(struct pnfs_layout_segment *lseg, struct nfs_page *req)
621 {
622 	u64 seg_last = pnfs_end_offset(lseg->pls_range.offset, lseg->pls_range.length);
623 	u64 req_last = req_offset(req) + req->wb_bytes;
624 
625 	return pnfs_is_range_intersecting(lseg->pls_range.offset, seg_last,
626 				req_offset(req), req_last);
627 }
628 
629 extern unsigned int layoutstats_timer;
630 
631 #ifdef NFS_DEBUG
632 void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id);
633 #else
634 static inline void nfs4_print_deviceid(const struct nfs4_deviceid *dev_id)
635 {
636 }
637 
638 #endif /* NFS_DEBUG */
639 #else  /* CONFIG_NFS_V4_1 */
640 
641 static inline bool nfs_have_layout(struct inode *inode)
642 {
643 	return false;
644 }
645 
646 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
647 {
648 }
649 
650 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
651 {
652 }
653 
654 static inline struct pnfs_layout_segment *
655 pnfs_get_lseg(struct pnfs_layout_segment *lseg)
656 {
657 	return NULL;
658 }
659 
660 static inline void pnfs_put_lseg(struct pnfs_layout_segment *lseg)
661 {
662 }
663 
664 static inline int pnfs_return_layout(struct inode *ino)
665 {
666 	return 0;
667 }
668 
669 static inline int pnfs_commit_and_return_layout(struct inode *inode)
670 {
671 	return 0;
672 }
673 
674 static inline bool
675 pnfs_ld_layoutret_on_setattr(struct inode *inode)
676 {
677 	return false;
678 }
679 
680 static inline bool
681 pnfs_ld_read_whole_page(struct inode *inode)
682 {
683 	return false;
684 }
685 
686 static inline int
687 pnfs_sync_inode(struct inode *inode, bool datasync)
688 {
689 	return 0;
690 }
691 
692 static inline bool
693 pnfs_layoutcommit_outstanding(struct inode *inode)
694 {
695 	return false;
696 }
697 
698 
699 static inline bool
700 pnfs_roc(struct inode *ino,
701 		struct nfs4_layoutreturn_args *args,
702 		struct nfs4_layoutreturn_res *res,
703 		const struct cred *cred)
704 {
705 	return false;
706 }
707 
708 static inline int
709 pnfs_roc_done(struct rpc_task *task, struct inode *inode,
710 		struct nfs4_layoutreturn_args **argpp,
711 		struct nfs4_layoutreturn_res **respp,
712 		int *ret)
713 {
714 	return 0;
715 }
716 
717 static inline void
718 pnfs_roc_release(struct nfs4_layoutreturn_args *args,
719 		struct nfs4_layoutreturn_res *res,
720 		int ret)
721 {
722 }
723 
724 static inline bool
725 pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
726 {
727 	return false;
728 }
729 
730 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
731 					 const struct nfs_fh *mntfh,
732 					 struct nfs_fsinfo *fsinfo)
733 {
734 }
735 
736 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
737 {
738 }
739 
740 static inline int
741 pnfs_commit_list(struct inode *inode, struct list_head *mds_pages, int how,
742 		 struct nfs_commit_info *cinfo)
743 {
744 	return PNFS_NOT_ATTEMPTED;
745 }
746 
747 static inline struct pnfs_ds_commit_info *
748 pnfs_get_ds_info(struct inode *inode)
749 {
750 	return NULL;
751 }
752 
753 static inline bool
754 pnfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
755 			 struct nfs_commit_info *cinfo, u32 ds_commit_idx)
756 {
757 	return false;
758 }
759 
760 static inline bool
761 pnfs_clear_request_commit(struct nfs_page *req, struct nfs_commit_info *cinfo)
762 {
763 	return false;
764 }
765 
766 static inline int
767 pnfs_scan_commit_lists(struct inode *inode, struct nfs_commit_info *cinfo,
768 		       int max)
769 {
770 	return 0;
771 }
772 
773 static inline struct nfs_page *
774 pnfs_search_commit_reqs(struct inode *inode, struct nfs_commit_info *cinfo,
775 			struct page *page)
776 {
777 	return NULL;
778 }
779 
780 static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync)
781 {
782 	return 0;
783 }
784 
785 static inline bool
786 pnfs_use_threshold(struct nfs4_threshold **dst, struct nfs4_threshold *src,
787 		   struct nfs_server *nfss)
788 {
789 	return false;
790 }
791 
792 static inline struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
793 {
794 	return NULL;
795 }
796 
797 static inline void nfs4_pnfs_v3_ds_connect_unload(void)
798 {
799 }
800 
801 static inline bool nfs4_layout_refresh_old_stateid(nfs4_stateid *dst,
802 		struct pnfs_layout_range *dst_range,
803 		struct inode *inode)
804 {
805 	return false;
806 }
807 
808 static inline void pnfs_lgopen_prepare(struct nfs4_opendata *data,
809 		struct nfs_open_context *ctx)
810 {
811 }
812 
813 static inline void pnfs_parse_lgopen(struct inode *ino,
814 		struct nfs4_layoutget *lgp,
815 		struct nfs_open_context *ctx)
816 {
817 }
818 
819 static inline void nfs4_lgopen_release(struct nfs4_layoutget *lgp)
820 {
821 }
822 
823 static inline bool pnfs_layout_is_valid(const struct pnfs_layout_hdr *lo)
824 {
825 	return false;
826 }
827 
828 #endif /* CONFIG_NFS_V4_1 */
829 
830 #if IS_ENABLED(CONFIG_NFS_V4_2)
831 int pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags);
832 #else
833 static inline int
834 pnfs_report_layoutstat(struct inode *inode, gfp_t gfp_flags)
835 {
836 	return 0;
837 }
838 #endif
839 
840 #endif /* FS_NFS_PNFS_H */
841