150 строки
4.3 KiB
C
150 строки
4.3 KiB
C
/* 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/swap.h>
|
|
#include <linux/nfs_fs.h>
|
|
#include <linux/nfs_mount.h>
|
|
#include <linux/nfs4_mount.h>
|
|
#include <linux/fscache.h>
|
|
#include <linux/iversion.h>
|
|
|
|
#ifdef CONFIG_NFS_FSCACHE
|
|
|
|
/*
|
|
* 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 {
|
|
s64 mtime_sec;
|
|
s64 mtime_nsec;
|
|
s64 ctime_sec;
|
|
s64 ctime_nsec;
|
|
u64 change_attr;
|
|
};
|
|
|
|
/*
|
|
* fscache.c
|
|
*/
|
|
extern int 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_release_file(struct inode *, struct file *);
|
|
|
|
extern int __nfs_fscache_read_page(struct inode *, struct page *);
|
|
extern void __nfs_fscache_write_page(struct inode *, struct page *);
|
|
|
|
static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
|
|
{
|
|
if (PageFsCache(page)) {
|
|
if (current_is_kswapd() || !(gfp & __GFP_FS))
|
|
return false;
|
|
wait_on_page_fscache(page);
|
|
fscache_note_page_release(nfs_i_fscache(page->mapping->host));
|
|
nfs_inc_fscache_stats(page->mapping->host,
|
|
NFSIOS_FSCACHE_PAGES_UNCACHED);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Retrieve a page from an inode data storage object.
|
|
*/
|
|
static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
|
|
{
|
|
if (nfs_i_fscache(inode))
|
|
return __nfs_fscache_read_page(inode, page);
|
|
return -ENOBUFS;
|
|
}
|
|
|
|
/*
|
|
* Store a page newly fetched from the server in an inode data storage object
|
|
* in the cache.
|
|
*/
|
|
static inline void nfs_fscache_write_page(struct inode *inode,
|
|
struct page *page)
|
|
{
|
|
if (nfs_i_fscache(inode))
|
|
__nfs_fscache_write_page(inode, page);
|
|
}
|
|
|
|
static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
|
|
struct inode *inode)
|
|
{
|
|
memset(auxdata, 0, sizeof(*auxdata));
|
|
auxdata->mtime_sec = inode->i_mtime.tv_sec;
|
|
auxdata->mtime_nsec = inode->i_mtime.tv_nsec;
|
|
auxdata->ctime_sec = inode->i_ctime.tv_sec;
|
|
auxdata->ctime_nsec = inode->i_ctime.tv_nsec;
|
|
|
|
if (NFS_SERVER(inode)->nfs_client->rpc_ops->version == 4)
|
|
auxdata->change_attr = inode_peek_iversion_raw(inode);
|
|
}
|
|
|
|
/*
|
|
* Invalidate the contents of fscache for this inode. This will not sleep.
|
|
*/
|
|
static inline void nfs_fscache_invalidate(struct inode *inode, int flags)
|
|
{
|
|
struct nfs_fscache_inode_auxdata auxdata;
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
|
|
if (nfsi->fscache) {
|
|
nfs_fscache_update_auxdata(&auxdata, inode);
|
|
fscache_invalidate(nfsi->fscache, &auxdata,
|
|
i_size_read(inode), flags);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* indicate the client caching state as readable text
|
|
*/
|
|
static inline const char *nfs_server_fscache_state(struct nfs_server *server)
|
|
{
|
|
if (server->fscache)
|
|
return "yes";
|
|
return "no ";
|
|
}
|
|
|
|
#else /* CONFIG_NFS_FSCACHE */
|
|
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 void nfs_fscache_release_file(struct inode *inode, struct file *file) {}
|
|
|
|
static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
|
|
{
|
|
return 1; /* True: may release page */
|
|
}
|
|
static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
|
|
{
|
|
return -ENOBUFS;
|
|
}
|
|
static inline void nfs_fscache_write_page(struct inode *inode, struct page *page) {}
|
|
static inline void nfs_fscache_invalidate(struct inode *inode, int flags) {}
|
|
|
|
static inline const char *nfs_server_fscache_state(struct nfs_server *server)
|
|
{
|
|
return "no ";
|
|
}
|
|
|
|
#endif /* CONFIG_NFS_FSCACHE */
|
|
#endif /* _NFS_FSCACHE_H */
|