[linux-2.6-block.git] / fs / nfs / fscache.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* NFS filesystem cache interface definitions
 *
 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#ifndef _NFS_FSCACHE_H
#define _NFS_FSCACHE_H

#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/fscache.h>

#ifdef CONFIG_NFS_FSCACHE

/*
 * set of NFS FS-Cache objects that form a superblock key
 */
struct nfs_fscache_key {
	struct rb_node		node;
	struct nfs_client	*nfs_client;	/* the server */

	/* the elements of the unique key - as used by nfs_compare_super() and
	 * nfs_compare_mount_options() to distinguish superblocks */
	struct {
		struct {
			unsigned long	s_flags;	/* various flags
							 * (& NFS_MS_MASK) */
		} super;

		struct {
			struct nfs_fsid fsid;
			int		flags;
			unsigned int	rsize;		/* read size */
			unsigned int	wsize;		/* write size */
			unsigned int	acregmin;	/* attr cache timeouts */
			unsigned int	acregmax;
			unsigned int	acdirmin;
			unsigned int	acdirmax;
		} nfs_server;

		struct {
			rpc_authflavor_t au_flavor;
		} rpc_auth;

		/* uniquifier - can be used if nfs_server.flags includes
		 * NFS_MOUNT_UNSHARED  */
		u8 uniq_len;
		char uniquifier[0];
	} key;
};

/*
 * Definition of the auxiliary data attached to NFS inode storage objects
 * within the cache.
 *
 * The contents of this struct are recorded in the on-disk local cache in the
 * auxiliary data attached to the data storage object backing an inode.  This
 * permits coherency to be managed when a new inode binds to an already extant
 * cache object.
 */
struct nfs_fscache_inode_auxdata {
	struct timespec	mtime;
	struct timespec	ctime;
	u64		change_attr;
};

/*
 * fscache-index.c
 */
extern struct fscache_netfs nfs_fscache_netfs;
extern const struct fscache_cookie_def nfs_fscache_server_index_def;
extern const struct fscache_cookie_def nfs_fscache_super_index_def;
extern const struct fscache_cookie_def nfs_fscache_inode_object_def;

extern int nfs_fscache_register(void);
extern void nfs_fscache_unregister(void);

/*
 * fscache.c
 */
extern void nfs_fscache_get_client_cookie(struct nfs_client *);
extern void nfs_fscache_release_client_cookie(struct nfs_client *);

extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
extern void nfs_fscache_release_super_cookie(struct super_block *);

extern void nfs_fscache_init_inode(struct inode *);
extern void nfs_fscache_clear_inode(struct inode *);
extern void nfs_fscache_open_file(struct inode *, struct file *);

extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
extern int nfs_fscache_release_page(struct page *, gfp_t);

extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
				       struct inode *, struct page *);
extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
					struct inode *, struct address_space *,
					struct list_head *, unsigned *);
extern void __nfs_readpage_to_fscache(struct inode *, struct page *, int);

/*
 * wait for a page to complete writing to the cache
 */
static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
						  struct page *page)
{
	if (PageFsCache(page))
		fscache_wait_on_page_write(nfsi->fscache, page);
}

/*
 * release the caching state associated with a page if undergoing complete page
 * invalidation
 */
static inline void nfs_fscache_invalidate_page(struct page *page,
					       struct inode *inode)
{
	if (PageFsCache(page))
		__nfs_fscache_invalidate_page(page, inode);
}

/*
 * Retrieve a page from an inode data storage object.
 */
static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
					    struct inode *inode,
					    struct page *page)
{
	if (NFS_I(inode)->fscache)
		return __nfs_readpage_from_fscache(ctx, inode, page);
	return -ENOBUFS;
}

/*
 * Retrieve a set of pages from an inode data storage object.
 */
static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
					     struct inode *inode,
					     struct address_space *mapping,
					     struct list_head *pages,
					     unsigned *nr_pages)
{
	if (NFS_I(inode)->fscache)
		return __nfs_readpages_from_fscache(ctx, inode, mapping, pages,
						    nr_pages);
	return -ENOBUFS;
}

/*
 * Store a page newly fetched from the server in an inode data storage object
 * in the cache.
 */
static inline void nfs_readpage_to_fscache(struct inode *inode,
					   struct page *page,
					   int sync)
{
	if (PageFsCache(page))
		__nfs_readpage_to_fscache(inode, page, sync);
}

/*
 * Invalidate the contents of fscache for this inode.  This will not sleep.
 */
static inline void nfs_fscache_invalidate(struct inode *inode)
{
	fscache_invalidate(NFS_I(inode)->fscache);
}

/*
 * Wait for an object to finish being invalidated.
 */
static inline void nfs_fscache_wait_on_invalidate(struct inode *inode)
{
	fscache_wait_on_invalidate(NFS_I(inode)->fscache);
}

/*
 * indicate the client caching state as readable text
 */
static inline const char *nfs_server_fscache_state(struct nfs_server *server)
{
	if (server->fscache && (server->options & NFS_OPTION_FSCACHE))
		return "yes";
	return "no ";
}

#else /* CONFIG_NFS_FSCACHE */
static inline int nfs_fscache_register(void) { return 0; }
static inline void nfs_fscache_unregister(void) {}

static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}

static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}

static inline void nfs_fscache_init_inode(struct inode *inode) {}
static inline void nfs_fscache_clear_inode(struct inode *inode) {}
static inline void nfs_fscache_open_file(struct inode *inode,
					 struct file *filp) {}

static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
{
	return 1; /* True: may release page */
}
static inline void nfs_fscache_invalidate_page(struct page *page,
					       struct inode *inode) {}
static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
						  struct page *page) {}

static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
					    struct inode *inode,
					    struct page *page)
{
	return -ENOBUFS;
}
static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
					     struct inode *inode,
					     struct address_space *mapping,
					     struct list_head *pages,
					     unsigned *nr_pages)
{
	return -ENOBUFS;
}
static inline void nfs_readpage_to_fscache(struct inode *inode,
					   struct page *page, int sync) {}


static inline void nfs_fscache_invalidate(struct inode *inode) {}
static inline void nfs_fscache_wait_on_invalidate(struct inode *inode) {}

static inline const char *nfs_server_fscache_state(struct nfs_server *server)
{
	return "no ";
}

#endif /* CONFIG_NFS_FSCACHE */
#endif /* _NFS_FSCACHE_H */
Commit	Line	Data
b4d0d230	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
8ec442ae DH	2	/* NFS filesystem cache interface definitions
	3	*
	4	* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
8ec442ae DH	6	*/
	7
	8	#ifndef _NFS_FSCACHE_H
	9	#define _NFS_FSCACHE_H
	10
	11	#include <linux/nfs_fs.h>
	12	#include <linux/nfs_mount.h>
	13	#include <linux/nfs4_mount.h>
	14	#include <linux/fscache.h>
	15
	16	#ifdef CONFIG_NFS_FSCACHE
	17
08734048 DH	18	/*
	19	* set of NFS FS-Cache objects that form a superblock key
	20	*/
	21	struct nfs_fscache_key {
	22	struct rb_node node;
	23	struct nfs_client nfs_client; / the server */
	24
	25	/* the elements of the unique key - as used by nfs_compare_super() and
	26	* nfs_compare_mount_options() to distinguish superblocks */
	27	struct {
	28	struct {
	29	unsigned long s_flags; /* various flags
	30	* (& NFS_MS_MASK) */
	31	} super;
	32
	33	struct {
	34	struct nfs_fsid fsid;
	35	int flags;
	36	unsigned int rsize; /* read size */
	37	unsigned int wsize; /* write size */
	38	unsigned int acregmin; /* attr cache timeouts */
	39	unsigned int acregmax;
	40	unsigned int acdirmin;
	41	unsigned int acdirmax;
	42	} nfs_server;
	43
	44	struct {
	45	rpc_authflavor_t au_flavor;
	46	} rpc_auth;
	47
	48	/* uniquifier - can be used if nfs_server.flags includes
	49	* NFS_MOUNT_UNSHARED */
	50	u8 uniq_len;
	51	char uniquifier[0];
	52	} key;
	53	};
	54
402cb8dd DH	55	/*
	56	* Definition of the auxiliary data attached to NFS inode storage objects
	57	* within the cache.
	58	*
	59	* The contents of this struct are recorded in the on-disk local cache in the
	60	* auxiliary data attached to the data storage object backing an inode. This
	61	* permits coherency to be managed when a new inode binds to an already extant
	62	* cache object.
	63	*/
	64	struct nfs_fscache_inode_auxdata {
	65	struct timespec mtime;
	66	struct timespec ctime;
402cb8dd DH	67	u64 change_attr;
	68	};
	69
8ec442ae DH	70	/*
	71	* fscache-index.c
	72	*/
	73	extern struct fscache_netfs nfs_fscache_netfs;
14727281	74	extern const struct fscache_cookie_def nfs_fscache_server_index_def;
08734048	75	extern const struct fscache_cookie_def nfs_fscache_super_index_def;
10329a5d	76	extern const struct fscache_cookie_def nfs_fscache_inode_object_def;
8ec442ae DH	77
	78	extern int nfs_fscache_register(void);
	79	extern void nfs_fscache_unregister(void);
	80
14727281 DH	81	/*
	82	* fscache.c
	83	*/
	84	extern void nfs_fscache_get_client_cookie(struct nfs_client *);
	85	extern void nfs_fscache_release_client_cookie(struct nfs_client *);
	86
2311b943	87	extern void nfs_fscache_get_super_cookie(struct super_block , const char , int);
08734048 DH	88	extern void nfs_fscache_release_super_cookie(struct super_block *);
08734048 DH	89
f1fe29b4 DH	90	extern void nfs_fscache_init_inode(struct inode *);
	91	extern void nfs_fscache_clear_inode(struct inode *);
	92	extern void nfs_fscache_open_file(struct inode , struct file );
ef79c097	93
545db45f DH	94	extern void __nfs_fscache_invalidate_page(struct page , struct inode );
	95	extern int nfs_fscache_release_page(struct page *, gfp_t);
	96
9a9fc1c0 DH	97	extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
	98	struct inode , struct page );
	99	extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
	100	struct inode , struct address_space ,
	101	struct list_head , unsigned );
7f8e05f6	102	extern void __nfs_readpage_to_fscache(struct inode , struct page , int);
9a9fc1c0	103
545db45f DH	104	/*
	105	* wait for a page to complete writing to the cache
	106	*/
	107	static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
	108	struct page *page)
	109	{
	110	if (PageFsCache(page))
	111	fscache_wait_on_page_write(nfsi->fscache, page);
	112	}
	113
	114	/*
	115	* release the caching state associated with a page if undergoing complete page
	116	* invalidation
	117	*/
	118	static inline void nfs_fscache_invalidate_page(struct page *page,
	119	struct inode *inode)
	120	{
	121	if (PageFsCache(page))
	122	__nfs_fscache_invalidate_page(page, inode);
	123	}
	124
9a9fc1c0 DH	125	/*
	126	* Retrieve a page from an inode data storage object.
	127	*/
	128	static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
	129	struct inode *inode,
	130	struct page *page)
	131	{
	132	if (NFS_I(inode)->fscache)
	133	return __nfs_readpage_from_fscache(ctx, inode, page);
	134	return -ENOBUFS;
	135	}
	136
	137	/*
	138	* Retrieve a set of pages from an inode data storage object.
	139	*/
	140	static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
	141	struct inode *inode,
	142	struct address_space *mapping,
	143	struct list_head *pages,
	144	unsigned *nr_pages)
	145	{
	146	if (NFS_I(inode)->fscache)
	147	return __nfs_readpages_from_fscache(ctx, inode, mapping, pages,
	148	nr_pages);
	149	return -ENOBUFS;
	150	}
545db45f	151
7f8e05f6 DH	152	/*
	153	* Store a page newly fetched from the server in an inode data storage object
	154	* in the cache.
	155	*/
	156	static inline void nfs_readpage_to_fscache(struct inode *inode,
	157	struct page *page,
	158	int sync)
	159	{
	160	if (PageFsCache(page))
	161	__nfs_readpage_to_fscache(inode, page, sync);
	162	}
	163
de242c0b DH	164	/*
	165	* Invalidate the contents of fscache for this inode. This will not sleep.
	166	*/
	167	static inline void nfs_fscache_invalidate(struct inode *inode)
	168	{
	169	fscache_invalidate(NFS_I(inode)->fscache);
	170	}
	171
	172	/*
	173	* Wait for an object to finish being invalidated.
	174	*/
	175	static inline void nfs_fscache_wait_on_invalidate(struct inode *inode)
	176	{
	177	fscache_wait_on_invalidate(NFS_I(inode)->fscache);
	178	}
	179
5d1acff1 DH	180	/*
	181	* indicate the client caching state as readable text
	182	*/
	183	static inline const char nfs_server_fscache_state(struct nfs_server server)
	184	{
	185	if (server->fscache && (server->options & NFS_OPTION_FSCACHE))
	186	return "yes";
	187	return "no ";
	188	}
	189
8ec442ae DH	190	#else /* CONFIG_NFS_FSCACHE */
	191	static inline int nfs_fscache_register(void) { return 0; }
	192	static inline void nfs_fscache_unregister(void) {}
	193
14727281 DH	194	static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
	195	static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
	196
08734048 DH	197	static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
08734048 DH	198
f1fe29b4 DH	199	static inline void nfs_fscache_init_inode(struct inode *inode) {}
	200	static inline void nfs_fscache_clear_inode(struct inode *inode) {}
	201	static inline void nfs_fscache_open_file(struct inode *inode,
	202	struct file *filp) {}
ef79c097	203
545db45f DH	204	static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
	205	{
	206	return 1; /* True: may release page */
	207	}
	208	static inline void nfs_fscache_invalidate_page(struct page *page,
	209	struct inode *inode) {}
	210	static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
	211	struct page *page) {}
	212
9a9fc1c0 DH	213	static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
	214	struct inode *inode,
	215	struct page *page)
	216	{
	217	return -ENOBUFS;
	218	}
	219	static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
	220	struct inode *inode,
	221	struct address_space *mapping,
	222	struct list_head *pages,
	223	unsigned *nr_pages)
	224	{
	225	return -ENOBUFS;
	226	}
7f8e05f6 DH	227	static inline void nfs_readpage_to_fscache(struct inode *inode,
7f8e05f6 DH	228	struct page *page, int sync) {}
9a9fc1c0	229
de242c0b DH	230
de242c0b DH	231	static inline void nfs_fscache_invalidate(struct inode *inode) {}
c129c293	232	static inline void nfs_fscache_wait_on_invalidate(struct inode *inode) {}
de242c0b	233
5d1acff1 DH	234	static inline const char nfs_server_fscache_state(struct nfs_server server)
	235	{
	236	return "no ";
	237	}
	238
8ec442ae DH	239	#endif /* CONFIG_NFS_FSCACHE */
8ec442ae DH	240	#endif /* _NFS_FSCACHE_H */