1/* SPDX-License-Identifier: LGPL-2.1 */
  2/*
  3 *   CIFS filesystem cache interface definitions
  4 *
  5 *   Copyright (c) 2010 Novell, Inc.
  6 *   Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
  7 *
  8 */
  9#ifndef _CIFS_FSCACHE_H
 10#define _CIFS_FSCACHE_H
 11
 12#include <linux/swap.h>
 13#include <linux/fscache.h>
 14
 15#include "cifsglob.h"
 16
 17/*
 18 * Coherency data attached to CIFS volume within the cache
 19 */
 20struct cifs_fscache_volume_coherency_data {
 21	__le64	resource_id;		/* unique server resource id */
 22	__le64	vol_create_time;
 23	__le32	vol_serial_number;
 24} __packed;
 25
 26/*
 27 * Coherency data attached to CIFS inode within the cache.
 28 */
 29struct cifs_fscache_inode_coherency_data {
 30	__le64 last_write_time_sec;
 31	__le64 last_change_time_sec;
 32	__le32 last_write_time_nsec;
 33	__le32 last_change_time_nsec;
 34};
 35
 36#ifdef CONFIG_CIFS_FSCACHE
 37
 38/*
 39 * fscache.c
 40 */
 41extern int cifs_fscache_get_super_cookie(struct cifs_tcon *);
 42extern void cifs_fscache_release_super_cookie(struct cifs_tcon *);
 43
 44extern void cifs_fscache_get_inode_cookie(struct inode *inode);
 45extern void cifs_fscache_release_inode_cookie(struct inode *);
 46extern void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update);
 47
 48static inline
 49void cifs_fscache_fill_coherency(struct inode *inode,
 50				 struct cifs_fscache_inode_coherency_data *cd)
 51{
 52	struct cifsInodeInfo *cifsi = CIFS_I(inode);
 53
 54	memset(cd, 0, sizeof(*cd));
 55	cd->last_write_time_sec   = cpu_to_le64(cifsi->netfs.inode.i_mtime.tv_sec);
 56	cd->last_write_time_nsec  = cpu_to_le32(cifsi->netfs.inode.i_mtime.tv_nsec);
 57	cd->last_change_time_sec  = cpu_to_le64(cifsi->netfs.inode.i_ctime.tv_sec);
 58	cd->last_change_time_nsec = cpu_to_le32(cifsi->netfs.inode.i_ctime.tv_nsec);
 59}
 60
 61
 62static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
 63{
 64	return netfs_i_cookie(&CIFS_I(inode)->netfs);
 65}
 66
 67static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags)
 68{
 69	struct cifs_fscache_inode_coherency_data cd;
 70
 71	cifs_fscache_fill_coherency(inode, &cd);
 72	fscache_invalidate(cifs_inode_cookie(inode), &cd,
 73			   i_size_read(inode), flags);
 74}
 75
 76extern int __cifs_fscache_query_occupancy(struct inode *inode,
 77					  pgoff_t first, unsigned int nr_pages,
 78					  pgoff_t *_data_first,
 79					  unsigned int *_data_nr_pages);
 80
 81static inline int cifs_fscache_query_occupancy(struct inode *inode,
 82					       pgoff_t first, unsigned int nr_pages,
 83					       pgoff_t *_data_first,
 84					       unsigned int *_data_nr_pages)
 85{
 86	if (!cifs_inode_cookie(inode))
 87		return -ENOBUFS;
 88	return __cifs_fscache_query_occupancy(inode, first, nr_pages,
 89					      _data_first, _data_nr_pages);
 90}
 91
 92extern int __cifs_readpage_from_fscache(struct inode *pinode, struct page *ppage);
 93extern void __cifs_readpage_to_fscache(struct inode *pinode, struct page *ppage);
 94
 95
 96static inline int cifs_readpage_from_fscache(struct inode *inode,
 97					     struct page *page)
 98{
 99	if (cifs_inode_cookie(inode))
100		return __cifs_readpage_from_fscache(inode, page);
101	return -ENOBUFS;
102}
103
104static inline void cifs_readpage_to_fscache(struct inode *inode,
105					    struct page *page)
106{
107	if (cifs_inode_cookie(inode))
108		__cifs_readpage_to_fscache(inode, page);
109}
110
111#else /* CONFIG_CIFS_FSCACHE */
112static inline
113void cifs_fscache_fill_coherency(struct inode *inode,
114				 struct cifs_fscache_inode_coherency_data *cd)
115{
116}
117
118static inline int cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) { return 0; }
119static inline void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) {}
120
121static inline void cifs_fscache_get_inode_cookie(struct inode *inode) {}
122static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
123static inline void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update) {}
124static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) { return NULL; }
125static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags) {}
126
127static inline int cifs_fscache_query_occupancy(struct inode *inode,
128					       pgoff_t first, unsigned int nr_pages,
129					       pgoff_t *_data_first,
130					       unsigned int *_data_nr_pages)
131{
132	*_data_first = ULONG_MAX;
133	*_data_nr_pages = 0;
134	return -ENOBUFS;
135}
136
137static inline int
138cifs_readpage_from_fscache(struct inode *inode, struct page *page)
139{
140	return -ENOBUFS;
141}
142
143static inline
144void cifs_readpage_to_fscache(struct inode *inode, struct page *page) {}
145
146#endif /* CONFIG_CIFS_FSCACHE */
147
148#endif /* _CIFS_FSCACHE_H */