mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![Abhishek Kulkarni](/assets/img/avatar_default.png)
This patch adds a persistent, read-only caching facility for 9p clients using the FS-Cache caching backend. When the fscache facility is enabled, each inode is associated with a corresponding vcookie which is an index into the FS-Cache indexing tree. The FS-Cache indexing tree is indexed at 3 levels: - session object associated with each mount. - inode/vcookie - actual data (pages) A cache tag is chosen randomly for each session. These tags can be read off /sys/fs/9p/caches and can be passed as a mount-time parameter to re-attach to the specified caching session. Signed-off-by: Abhishek Kulkarni <adkulkar@umail.iu.edu> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
176 lines
4.8 KiB
C
176 lines
4.8 KiB
C
/*
|
|
* V9FS cache definitions.
|
|
*
|
|
* Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to:
|
|
* Free Software Foundation
|
|
* 51 Franklin Street, Fifth Floor
|
|
* Boston, MA 02111-1301 USA
|
|
*
|
|
*/
|
|
|
|
#ifndef _9P_CACHE_H
|
|
#ifdef CONFIG_9P_FSCACHE
|
|
#include <linux/fscache.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
extern struct kmem_cache *vcookie_cache;
|
|
|
|
struct v9fs_cookie {
|
|
spinlock_t lock;
|
|
struct inode inode;
|
|
struct fscache_cookie *fscache;
|
|
struct p9_qid *qid;
|
|
};
|
|
|
|
static inline struct v9fs_cookie *v9fs_inode2cookie(const struct inode *inode)
|
|
{
|
|
return container_of(inode, struct v9fs_cookie, inode);
|
|
}
|
|
|
|
extern struct fscache_netfs v9fs_cache_netfs;
|
|
extern const struct fscache_cookie_def v9fs_cache_session_index_def;
|
|
extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
|
|
|
|
extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
|
|
extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
|
|
|
|
extern void v9fs_cache_inode_get_cookie(struct inode *inode);
|
|
extern void v9fs_cache_inode_put_cookie(struct inode *inode);
|
|
extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
|
|
extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
|
|
extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
|
|
|
|
extern int __v9fs_cache_register(void);
|
|
extern void __v9fs_cache_unregister(void);
|
|
|
|
extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
|
|
extern void __v9fs_fscache_invalidate_page(struct page *page);
|
|
extern int __v9fs_readpage_from_fscache(struct inode *inode,
|
|
struct page *page);
|
|
extern int __v9fs_readpages_from_fscache(struct inode *inode,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned *nr_pages);
|
|
extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
|
|
|
|
|
|
/**
|
|
* v9fs_cache_register - Register v9fs file system with the cache
|
|
*/
|
|
static inline int v9fs_cache_register(void)
|
|
{
|
|
return __v9fs_cache_register();
|
|
}
|
|
|
|
/**
|
|
* v9fs_cache_unregister - Unregister v9fs from the cache
|
|
*/
|
|
static inline void v9fs_cache_unregister(void)
|
|
{
|
|
__v9fs_cache_unregister();
|
|
}
|
|
|
|
static inline int v9fs_fscache_release_page(struct page *page,
|
|
gfp_t gfp)
|
|
{
|
|
return __v9fs_fscache_release_page(page, gfp);
|
|
}
|
|
|
|
static inline void v9fs_fscache_invalidate_page(struct page *page)
|
|
{
|
|
__v9fs_fscache_invalidate_page(page);
|
|
}
|
|
|
|
static inline int v9fs_readpage_from_fscache(struct inode *inode,
|
|
struct page *page)
|
|
{
|
|
return __v9fs_readpage_from_fscache(inode, page);
|
|
}
|
|
|
|
static inline int v9fs_readpages_from_fscache(struct inode *inode,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned *nr_pages)
|
|
{
|
|
return __v9fs_readpages_from_fscache(inode, mapping, pages,
|
|
nr_pages);
|
|
}
|
|
|
|
static inline void v9fs_readpage_to_fscache(struct inode *inode,
|
|
struct page *page)
|
|
{
|
|
if (PageFsCache(page))
|
|
__v9fs_readpage_to_fscache(inode, page);
|
|
}
|
|
|
|
static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
|
|
{
|
|
struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
|
|
fscache_uncache_page(vcookie->fscache, page);
|
|
BUG_ON(PageFsCache(page));
|
|
}
|
|
|
|
static inline void v9fs_vcookie_set_qid(struct inode *inode,
|
|
struct p9_qid *qid)
|
|
{
|
|
struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
|
|
spin_lock(&vcookie->lock);
|
|
vcookie->qid = qid;
|
|
spin_unlock(&vcookie->lock);
|
|
}
|
|
|
|
#else /* CONFIG_9P_FSCACHE */
|
|
|
|
static inline int v9fs_cache_register(void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static inline void v9fs_cache_unregister(void) {}
|
|
|
|
static inline int v9fs_fscache_release_page(struct page *page,
|
|
gfp_t gfp) {
|
|
return 1;
|
|
}
|
|
|
|
static inline void v9fs_fscache_invalidate_page(struct page *page) {}
|
|
|
|
static inline int v9fs_readpage_from_fscache(struct inode *inode,
|
|
struct page *page)
|
|
{
|
|
return -ENOBUFS;
|
|
}
|
|
|
|
static inline int v9fs_readpages_from_fscache(struct inode *inode,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned *nr_pages)
|
|
{
|
|
return -ENOBUFS;
|
|
}
|
|
|
|
static inline void v9fs_readpage_to_fscache(struct inode *inode,
|
|
struct page *page)
|
|
{}
|
|
|
|
static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
|
|
{}
|
|
|
|
static inline void v9fs_vcookie_set_qid(struct inode *inode,
|
|
struct p9_qid *qid)
|
|
{}
|
|
|
|
#endif /* CONFIG_9P_FSCACHE */
|
|
#endif /* _9P_CACHE_H */
|