summaryrefslogtreecommitdiff
path: root/include/linux/netfs.h
blob: d2d291a9cdadba94743daf38cb7ad56bad99ebf3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Network filesystem support services.
 *
 * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * See:
 *
 *	Documentation/filesystems/netfs_library.rst
 *
 * for a description of the network filesystem interface declared here.
 */

#ifndef _LINUX_NETFS_H
#define _LINUX_NETFS_H

#include <linux/workqueue.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/uio.h>

enum netfs_sreq_ref_trace;
typedef struct mempool_s mempool_t;

/**
 * folio_start_private_2 - Start an fscache write on a folio.  [DEPRECATED]
 * @folio: The folio.
 *
 * Call this function before writing a folio to a local cache.  Starting a
 * second write before the first one finishes is not allowed.
 *
 * Note that this should no longer be used.
 */
static inline void folio_start_private_2(struct folio *folio)
{
	VM_BUG_ON_FOLIO(folio_test_private_2(folio), folio);
	folio_get(folio);
	folio_set_private_2(folio);
}

/* Marks used on xarray-based buffers */
#define NETFS_BUF_PUT_MARK	XA_MARK_0	/* - Page needs putting  */
#define NETFS_BUF_PAGECACHE_MARK XA_MARK_1	/* - Page needs wb/dirty flag wrangling */

enum netfs_io_source {
	NETFS_FILL_WITH_ZEROES,
	NETFS_DOWNLOAD_FROM_SERVER,
	NETFS_READ_FROM_CACHE,
	NETFS_INVALID_READ,
	NETFS_UPLOAD_TO_SERVER,
	NETFS_WRITE_TO_CACHE,
	NETFS_INVALID_WRITE,
} __mode(byte);

typedef void (*netfs_io_terminated_t)(void *priv, ssize_t transferred_or_error,
				      bool was_async);

/*
 * Per-inode context.  This wraps the VFS inode.
 */
struct netfs_inode {
	struct inode		inode;		/* The VFS inode */
	const struct netfs_request_ops *ops;
#if IS_ENABLED(CONFIG_FSCACHE)
	struct fscache_cookie	*cache;
#endif
	struct mutex		wb_lock;	/* Writeback serialisation */
	loff_t			remote_i_size;	/* Size of the remote file */
	loff_t			zero_point;	/* Size after which we assume there's no data
						 * on the server */
	unsigned long		flags;
#define NETFS_ICTX_ODIRECT	0		/* The file has DIO in progress */
#define NETFS_ICTX_UNBUFFERED	1		/* I/O should not use the pagecache */
#define NETFS_ICTX_WRITETHROUGH	2		/* Write-through caching */
#define NETFS_ICTX_USE_PGPRIV2	31		/* [DEPRECATED] Use PG_private_2 to mark
						 * write to cache on read */
};

/*
 * A netfs group - for instance a ceph snap.  This is marked on dirty pages and
 * pages marked with a group must be flushed before they can be written under
 * the domain of another group.
 */
struct netfs_group {
	refcount_t		ref;
	void (*free)(struct netfs_group *netfs_group);
};

/*
 * Information about a dirty page (attached only if necessary).
 * folio->private
 */
struct netfs_folio {
	struct netfs_group	*netfs_group;	/* Filesystem's grouping marker (or NULL). */
	unsigned int		dirty_offset;	/* Write-streaming dirty data offset */
	unsigned int		dirty_len;	/* Write-streaming dirty data length */
};
#define NETFS_FOLIO_INFO	0x1UL	/* OR'd with folio->private. */
#define NETFS_FOLIO_COPY_TO_CACHE ((struct netfs_group *)0x356UL) /* Write to the cache only */

static inline bool netfs_is_folio_info(const void *priv)
{
	return (unsigned long)priv & NETFS_FOLIO_INFO;
}

static inline struct netfs_folio *__netfs_folio_info(const void *priv)
{
	if (netfs_is_folio_info(priv))
		return (struct netfs_folio *)((unsigned long)priv & ~NETFS_FOLIO_INFO);
	return NULL;
}

static inline struct netfs_folio *netfs_folio_info(struct folio *folio)
{
	return __netfs_folio_info(folio_get_private(folio));
}

static inline struct netfs_group *netfs_folio_group(struct folio *folio)
{
	struct netfs_folio *finfo;
	void *priv = folio_get_private(folio);

	finfo = netfs_folio_info(folio);
	if (finfo)
		return finfo->netfs_group;
	return priv;
}

/*
 * Stream of I/O subrequests going to a particular destination, such as the
 * server or the local cache.  This is mainly intended for writing where we may
 * have to write to multiple destinations concurrently.
 */
struct netfs_io_stream {
	/* Submission tracking */
	struct netfs_io_subrequest *construct;	/* Op being constructed */
	unsigned int		submit_off;	/* Folio offset we're submitting from */
	unsigned int		submit_len;	/* Amount of data left to submit */
	unsigned int		submit_max_len;	/* Amount I/O can be rounded up to */
	void (*prepare_write)(struct netfs_io_subrequest *subreq);
	void (*issue_write)(struct netfs_io_subrequest *subreq);
	/* Collection tracking */
	struct list_head	subrequests;	/* Contributory I/O operations */
	struct netfs_io_subrequest *front;	/* Op being collected */
	unsigned long long	collected_to;	/* Position we've collected results to */
	size_t			transferred;	/* The amount transferred from this stream */
	enum netfs_io_source	source;		/* Where to read from/write to */
	unsigned short		error;		/* Aggregate error for the stream */
	unsigned char		stream_nr;	/* Index of stream in parent table */
	bool			avail;		/* T if stream is available */
	bool			active;		/* T if stream is active */
	bool			need_retry;	/* T if this stream needs retrying */
	bool			failed;		/* T if this stream failed */
};

/*
 * Resources required to do operations on a cache.
 */
struct netfs_cache_resources {
	const struct netfs_cache_ops	*ops;
	void				*cache_priv;
	void				*cache_priv2;
	unsigned int			debug_id;	/* Cookie debug ID */
	unsigned int			inval_counter;	/* object->inval_counter at begin_op */
};

/*
 * Descriptor for a single component subrequest.  Each operation represents an
 * individual read/write from/to a server, a cache, a journal, etc..
 *
 * The buffer iterator is persistent for the life of the subrequest struct and
 * the pages it points to can be relied on to exist for the duration.
 */
struct netfs_io_subrequest {
	struct netfs_io_request *rreq;		/* Supervising I/O request */
	struct work_struct	work;
	struct list_head	rreq_link;	/* Link in rreq->subrequests */
	struct iov_iter		io_iter;	/* Iterator for this subrequest */
	unsigned long long	start;		/* Where to start the I/O */
	size_t			max_len;	/* Maximum size of the I/O */
	size_t			len;		/* Size of the I/O */
	size_t			transferred;	/* Amount of data transferred */
	refcount_t		ref;
	short			error;		/* 0 or error that occurred */
	unsigned short		debug_index;	/* Index in list (for debugging output) */
	unsigned int		nr_segs;	/* Number of segs in io_iter */
	unsigned int		max_nr_segs;	/* 0 or max number of segments in an iterator */
	enum netfs_io_source	source;		/* Where to read from/write to */
	unsigned char		stream_nr;	/* I/O stream this belongs to */
	unsigned long		flags;
#define NETFS_SREQ_COPY_TO_CACHE	0	/* Set if should copy the data to the cache */
#define NETFS_SREQ_CLEAR_TAIL		1	/* Set if the rest of the read should be cleared */
#define NETFS_SREQ_SHORT_IO		2	/* Set if the I/O was short */
#define NETFS_SREQ_SEEK_DATA_READ	3	/* Set if ->read() should SEEK_DATA first */
#define NETFS_SREQ_NO_PROGRESS		4	/* Set if we didn't manage to read any data */
#define NETFS_SREQ_ONDEMAND		5	/* Set if it's from on-demand read mode */
#define NETFS_SREQ_BOUNDARY		6	/* Set if ends on hard boundary (eg. ceph object) */
#define NETFS_SREQ_IN_PROGRESS		8	/* Unlocked when the subrequest completes */
#define NETFS_SREQ_NEED_RETRY		9	/* Set if the filesystem requests a retry */
#define NETFS_SREQ_RETRYING		10	/* Set if we're retrying */
#define NETFS_SREQ_FAILED		11	/* Set if the subreq failed unretryably */
};

enum netfs_io_origin {
	NETFS_READAHEAD,		/* This read was triggered by readahead */
	NETFS_READPAGE,			/* This read is a synchronous read */
	NETFS_READ_FOR_WRITE,		/* This read is to prepare a write */
	NETFS_COPY_TO_CACHE,		/* This write is to copy a read to the cache */
	NETFS_WRITEBACK,		/* This write was triggered by writepages */
	NETFS_WRITETHROUGH,		/* This write was made by netfs_perform_write() */
	NETFS_UNBUFFERED_WRITE,		/* This is an unbuffered write */
	NETFS_DIO_READ,			/* This is a direct I/O read */
	NETFS_DIO_WRITE,		/* This is a direct I/O write */
	nr__netfs_io_origin
} __mode(byte);

/*
 * Descriptor for an I/O helper request.  This is used to make multiple I/O
 * operations to a variety of data stores and then stitch the result together.
 */
struct netfs_io_request {
	union {
		struct work_struct work;
		struct rcu_head rcu;
	};
	struct inode		*inode;		/* The file being accessed */
	struct address_space	*mapping;	/* The mapping being accessed */
	struct kiocb		*iocb;		/* AIO completion vector */
	struct netfs_cache_resources cache_resources;
	struct list_head	proc_link;	/* Link in netfs_iorequests */
	struct list_head	subrequests;	/* Contributory I/O operations */
	struct netfs_io_stream	io_streams[2];	/* Streams of parallel I/O operations */
#define NR_IO_STREAMS 2 //wreq->nr_io_streams
	struct netfs_group	*group;		/* Writeback group being written back */
	struct iov_iter		iter;		/* Unencrypted-side iterator */
	struct iov_iter		io_iter;	/* I/O (Encrypted-side) iterator */
	void			*netfs_priv;	/* Private data for the netfs */
	void			*netfs_priv2;	/* Private data for the netfs */
	struct bio_vec		*direct_bv;	/* DIO buffer list (when handling iovec-iter) */
	unsigned int		direct_bv_count; /* Number of elements in direct_bv[] */
	unsigned int		debug_id;
	unsigned int		rsize;		/* Maximum read size (0 for none) */
	unsigned int		wsize;		/* Maximum write size (0 for none) */
	atomic_t		subreq_counter;	/* Next subreq->debug_index */
	unsigned int		nr_group_rel;	/* Number of refs to release on ->group */
	spinlock_t		lock;		/* Lock for queuing subreqs */
	atomic_t		nr_outstanding;	/* Number of ops in progress */
	atomic_t		nr_copy_ops;	/* Number of copy-to-cache ops in progress */
	size_t			upper_len;	/* Length can be extended to here */
	unsigned long long	submitted;	/* Amount submitted for I/O so far */
	unsigned long long	len;		/* Length of the request */
	size_t			transferred;	/* Amount to be indicated as transferred */
	short			error;		/* 0 or error that occurred */
	enum netfs_io_origin	origin;		/* Origin of the request */
	bool			direct_bv_unpin; /* T if direct_bv[] must be unpinned */
	unsigned long long	i_size;		/* Size of the file */
	unsigned long long	start;		/* Start position */
	atomic64_t		issued_to;	/* Write issuer folio cursor */
	unsigned long long	contiguity;	/* Tracking for gaps in the writeback sequence */
	unsigned long long	collected_to;	/* Point we've collected to */
	unsigned long long	cleaned_to;	/* Position we've cleaned folios to */
	pgoff_t			no_unlock_folio; /* Don't unlock this folio after read */
	refcount_t		ref;
	unsigned long		flags;
#define NETFS_RREQ_INCOMPLETE_IO	0	/* Some ioreqs terminated short or with error */
#define NETFS_RREQ_COPY_TO_CACHE	1	/* Need to write to the cache */
#define NETFS_RREQ_NO_UNLOCK_FOLIO	2	/* Don't unlock no_unlock_folio on completion */
#define NETFS_RREQ_DONT_UNLOCK_FOLIOS	3	/* Don't unlock the folios on completion */
#define NETFS_RREQ_FAILED		4	/* The request failed */
#define NETFS_RREQ_IN_PROGRESS		5	/* Unlocked when the request completes */
#define NETFS_RREQ_WRITE_TO_CACHE	7	/* Need to write to the cache */
#define NETFS_RREQ_UPLOAD_TO_SERVER	8	/* Need to write to the server */
#define NETFS_RREQ_NONBLOCK		9	/* Don't block if possible (O_NONBLOCK) */
#define NETFS_RREQ_BLOCKED		10	/* We blocked */
#define NETFS_RREQ_PAUSE		11	/* Pause subrequest generation */
#define NETFS_RREQ_USE_IO_ITER		12	/* Use ->io_iter rather than ->i_pages */
#define NETFS_RREQ_ALL_QUEUED		13	/* All subreqs are now queued */
#define NETFS_RREQ_USE_PGPRIV2		31	/* [DEPRECATED] Use PG_private_2 to mark
						 * write to cache on read */
	const struct netfs_request_ops *netfs_ops;
	void (*cleanup)(struct netfs_io_request *req);
};

/*
 * Operations the network filesystem can/must provide to the helpers.
 */
struct netfs_request_ops {
	mempool_t *request_pool;
	mempool_t *subrequest_pool;
	int (*init_request)(struct netfs_io_request *rreq, struct file *file);
	void (*free_request)(struct netfs_io_request *rreq);
	void (*free_subrequest)(struct netfs_io_subrequest *rreq);

	/* Read request handling */
	void (*expand_readahead)(struct netfs_io_request *rreq);
	bool (*clamp_length)(struct netfs_io_subrequest *subreq);
	void (*issue_read)(struct netfs_io_subrequest *subreq);
	bool (*is_still_valid)(struct netfs_io_request *rreq);
	int (*check_write_begin)(struct file *file, loff_t pos, unsigned len,
				 struct folio **foliop, void **_fsdata);
	void (*done)(struct netfs_io_request *rreq);

	/* Modification handling */
	void (*update_i_size)(struct inode *inode, loff_t i_size);
	void (*post_modify)(struct inode *inode);

	/* Write request handling */
	void (*begin_writeback)(struct netfs_io_request *wreq);
	void (*prepare_write)(struct netfs_io_subrequest *subreq);
	void (*issue_write)(struct netfs_io_subrequest *subreq);
	void (*retry_request)(struct netfs_io_request *wreq, struct netfs_io_stream *stream);
	void (*invalidate_cache)(struct netfs_io_request *wreq);
};

/*
 * How to handle reading from a hole.
 */
enum netfs_read_from_hole {
	NETFS_READ_HOLE_IGNORE,
	NETFS_READ_HOLE_CLEAR,
	NETFS_READ_HOLE_FAIL,
};

/*
 * Table of operations for access to a cache.
 */
struct netfs_cache_ops {
	/* End an operation */
	void (*end_operation)(struct netfs_cache_resources *cres);

	/* Read data from the cache */
	int (*read)(struct netfs_cache_resources *cres,
		    loff_t start_pos,
		    struct iov_iter *iter,
		    enum netfs_read_from_hole read_hole,
		    netfs_io_terminated_t term_func,
		    void *term_func_priv);

	/* Write data to the cache */
	int (*write)(struct netfs_cache_resources *cres,
		     loff_t start_pos,
		     struct iov_iter *iter,
		     netfs_io_terminated_t term_func,
		     void *term_func_priv);

	/* Write data to the cache from a netfs subrequest. */
	void (*issue_write)(struct netfs_io_subrequest *subreq);

	/* Expand readahead request */
	void (*expand_readahead)(struct netfs_cache_resources *cres,
				 unsigned long long *_start,
				 unsigned long long *_len,
				 unsigned long long i_size);

	/* Prepare a read operation, shortening it to a cached/uncached
	 * boundary as appropriate.
	 */
	enum netfs_io_source (*prepare_read)(struct netfs_io_subrequest *subreq,
					     unsigned long long i_size);

	/* Prepare a write subrequest, working out if we're allowed to do it
	 * and finding out the maximum amount of data to gather before
	 * attempting to submit.  If we're not permitted to do it, the
	 * subrequest should be marked failed.
	 */
	void (*prepare_write_subreq)(struct netfs_io_subrequest *subreq);

	/* Prepare a write operation, working out what part of the write we can
	 * actually do.
	 */
	int (*prepare_write)(struct netfs_cache_resources *cres,
			     loff_t *_start, size_t *_len, size_t upper_len,
			     loff_t i_size, bool no_space_allocated_yet);

	/* Prepare an on-demand read operation, shortening it to a cached/uncached
	 * boundary as appropriate.
	 */
	enum netfs_io_source (*prepare_ondemand_read)(struct netfs_cache_resources *cres,
						      loff_t start, size_t *_len,
						      loff_t i_size,
						      unsigned long *_flags, ino_t ino);

	/* Query the occupancy of the cache in a region, returning where the
	 * next chunk of data starts and how long it is.
	 */
	int (*query_occupancy)(struct netfs_cache_resources *cres,
			       loff_t start, size_t len, size_t granularity,
			       loff_t *_data_start, size_t *_data_len);
};

/* High-level read API. */
ssize_t netfs_unbuffered_read_iter_locked(struct kiocb *iocb, struct iov_iter *iter);
ssize_t netfs_unbuffered_read_iter(struct kiocb *iocb, struct iov_iter *iter);
ssize_t netfs_buffered_read_iter(struct kiocb *iocb, struct iov_iter *iter);
ssize_t netfs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter);

/* High-level write API */
ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
			    struct netfs_group *netfs_group);
ssize_t netfs_buffered_write_iter_locked(struct kiocb *iocb, struct iov_iter *from,
					 struct netfs_group *netfs_group);
ssize_t netfs_unbuffered_write_iter(struct kiocb *iocb, struct iov_iter *from);
ssize_t netfs_unbuffered_write_iter_locked(struct kiocb *iocb, struct iov_iter *iter,
					   struct netfs_group *netfs_group);
ssize_t netfs_file_write_iter(struct kiocb *iocb, struct iov_iter *from);

/* Address operations API */
struct readahead_control;
void netfs_readahead(struct readahead_control *);
int netfs_read_folio(struct file *, struct folio *);
int netfs_write_begin(struct netfs_inode *, struct file *,
		      struct address_space *, loff_t pos, unsigned int len,
		      struct folio **, void **fsdata);
int netfs_writepages(struct address_space *mapping,
		     struct writeback_control *wbc);
bool netfs_dirty_folio(struct address_space *mapping, struct folio *folio);
int netfs_unpin_writeback(struct inode *inode, struct writeback_control *wbc);
void netfs_clear_inode_writeback(struct inode *inode, const void *aux);
void netfs_invalidate_folio(struct folio *folio, size_t offset, size_t length);
bool netfs_release_folio(struct folio *folio, gfp_t gfp);

/* VMA operations API. */
vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf, struct netfs_group *netfs_group);

/* (Sub)request management API. */
void netfs_subreq_terminated(struct netfs_io_subrequest *, ssize_t, bool);
void netfs_get_subrequest(struct netfs_io_subrequest *subreq,
			  enum netfs_sreq_ref_trace what);
void netfs_put_subrequest(struct netfs_io_subrequest *subreq,
			  bool was_async, enum netfs_sreq_ref_trace what);
ssize_t netfs_extract_user_iter(struct iov_iter *orig, size_t orig_len,
				struct iov_iter *new,
				iov_iter_extraction_t extraction_flags);
size_t netfs_limit_iter(const struct iov_iter *iter, size_t start_offset,
			size_t max_size, size_t max_segs);
void netfs_prepare_write_failed(struct netfs_io_subrequest *subreq);
void netfs_write_subrequest_terminated(void *_op, ssize_t transferred_or_error,
				       bool was_async);
void netfs_queue_write_request(struct netfs_io_subrequest *subreq);

int netfs_start_io_read(struct inode *inode);
void netfs_end_io_read(struct inode *inode);
int netfs_start_io_write(struct inode *inode);
void netfs_end_io_write(struct inode *inode);
int netfs_start_io_direct(struct inode *inode);
void netfs_end_io_direct(struct inode *inode);

/**
 * netfs_inode - Get the netfs inode context from the inode
 * @inode: The inode to query
 *
 * Get the netfs lib inode context from the network filesystem's inode.  The
 * context struct is expected to directly follow on from the VFS inode struct.
 */
static inline struct netfs_inode *netfs_inode(struct inode *inode)
{
	return container_of(inode, struct netfs_inode, inode);
}

/**
 * netfs_inode_init - Initialise a netfslib inode context
 * @ctx: The netfs inode to initialise
 * @ops: The netfs's operations list
 * @use_zero_point: True to use the zero_point read optimisation
 *
 * Initialise the netfs library context struct.  This is expected to follow on
 * directly from the VFS inode struct.
 */
static inline void netfs_inode_init(struct netfs_inode *ctx,
				    const struct netfs_request_ops *ops,
				    bool use_zero_point)
{
	ctx->ops = ops;
	ctx->remote_i_size = i_size_read(&ctx->inode);
	ctx->zero_point = LLONG_MAX;
	ctx->flags = 0;
#if IS_ENABLED(CONFIG_FSCACHE)
	ctx->cache = NULL;
#endif
	mutex_init(&ctx->wb_lock);
	/* ->releasepage() drives zero_point */
	if (use_zero_point) {
		ctx->zero_point = ctx->remote_i_size;
		mapping_set_release_always(ctx->inode.i_mapping);
	}
}

/**
 * netfs_resize_file - Note that a file got resized
 * @ctx: The netfs inode being resized
 * @new_i_size: The new file size
 * @changed_on_server: The change was applied to the server
 *
 * Inform the netfs lib that a file got resized so that it can adjust its state.
 */
static inline void netfs_resize_file(struct netfs_inode *ctx, loff_t new_i_size,
				     bool changed_on_server)
{
	if (changed_on_server)
		ctx->remote_i_size = new_i_size;
	if (new_i_size < ctx->zero_point)
		ctx->zero_point = new_i_size;
}

/**
 * netfs_i_cookie - Get the cache cookie from the inode
 * @ctx: The netfs inode to query
 *
 * Get the caching cookie (if enabled) from the network filesystem's inode.
 */
static inline struct fscache_cookie *netfs_i_cookie(struct netfs_inode *ctx)
{
#if IS_ENABLED(CONFIG_FSCACHE)
	return ctx->cache;
#else
	return NULL;
#endif
}

#endif /* _LINUX_NETFS_H */