linux-stable/include/linux/cleancache.h
Dan Magenheimer 91c6cc9b5c mm: zcache/tmem/cleancache: s/flush/invalidate/
Complete the renaming from "flush" to "invalidate" across
both tmem frontends (cleancache and frontswap) and both tmem backends
(Xen and zcache), as required by akpm.

This change is completely cosmetic.

[v10: no change]
[v9: akpm@linux-foundation.org: change "flush" to "invalidate", part 3]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@novell.com>
Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Rik Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
[v11: Remove the frontswap part]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-23 16:06:37 -05:00

122 lines
3.8 KiB
C

#ifndef _LINUX_CLEANCACHE_H
#define _LINUX_CLEANCACHE_H
#include <linux/fs.h>
#include <linux/exportfs.h>
#include <linux/mm.h>
#define CLEANCACHE_KEY_MAX 6
/*
* cleancache requires every file with a page in cleancache to have a
* unique key unless/until the file is removed/truncated. For some
* filesystems, the inode number is unique, but for "modern" filesystems
* an exportable filehandle is required (see exportfs.h)
*/
struct cleancache_filekey {
union {
ino_t ino;
__u32 fh[CLEANCACHE_KEY_MAX];
u32 key[CLEANCACHE_KEY_MAX];
} u;
};
struct cleancache_ops {
int (*init_fs)(size_t);
int (*init_shared_fs)(char *uuid, size_t);
int (*get_page)(int, struct cleancache_filekey,
pgoff_t, struct page *);
void (*put_page)(int, struct cleancache_filekey,
pgoff_t, struct page *);
void (*invalidate_page)(int, struct cleancache_filekey, pgoff_t);
void (*invalidate_inode)(int, struct cleancache_filekey);
void (*invalidate_fs)(int);
};
extern struct cleancache_ops
cleancache_register_ops(struct cleancache_ops *ops);
extern void __cleancache_init_fs(struct super_block *);
extern void __cleancache_init_shared_fs(char *, struct super_block *);
extern int __cleancache_get_page(struct page *);
extern void __cleancache_put_page(struct page *);
extern void __cleancache_invalidate_page(struct address_space *, struct page *);
extern void __cleancache_invalidate_inode(struct address_space *);
extern void __cleancache_invalidate_fs(struct super_block *);
extern int cleancache_enabled;
#ifdef CONFIG_CLEANCACHE
static inline bool cleancache_fs_enabled(struct page *page)
{
return page->mapping->host->i_sb->cleancache_poolid >= 0;
}
static inline bool cleancache_fs_enabled_mapping(struct address_space *mapping)
{
return mapping->host->i_sb->cleancache_poolid >= 0;
}
#else
#define cleancache_enabled (0)
#define cleancache_fs_enabled(_page) (0)
#define cleancache_fs_enabled_mapping(_page) (0)
#endif
/*
* The shim layer provided by these inline functions allows the compiler
* to reduce all cleancache hooks to nothingness if CONFIG_CLEANCACHE
* is disabled, to a single global variable check if CONFIG_CLEANCACHE
* is enabled but no cleancache "backend" has dynamically enabled it,
* and, for the most frequent cleancache ops, to a single global variable
* check plus a superblock element comparison if CONFIG_CLEANCACHE is enabled
* and a cleancache backend has dynamically enabled cleancache, but the
* filesystem referenced by that cleancache op has not enabled cleancache.
* As a result, CONFIG_CLEANCACHE can be enabled by default with essentially
* no measurable performance impact.
*/
static inline void cleancache_init_fs(struct super_block *sb)
{
if (cleancache_enabled)
__cleancache_init_fs(sb);
}
static inline void cleancache_init_shared_fs(char *uuid, struct super_block *sb)
{
if (cleancache_enabled)
__cleancache_init_shared_fs(uuid, sb);
}
static inline int cleancache_get_page(struct page *page)
{
int ret = -1;
if (cleancache_enabled && cleancache_fs_enabled(page))
ret = __cleancache_get_page(page);
return ret;
}
static inline void cleancache_put_page(struct page *page)
{
if (cleancache_enabled && cleancache_fs_enabled(page))
__cleancache_put_page(page);
}
static inline void cleancache_invalidate_page(struct address_space *mapping,
struct page *page)
{
/* careful... page->mapping is NULL sometimes when this is called */
if (cleancache_enabled && cleancache_fs_enabled_mapping(mapping))
__cleancache_invalidate_page(mapping, page);
}
static inline void cleancache_invalidate_inode(struct address_space *mapping)
{
if (cleancache_enabled && cleancache_fs_enabled_mapping(mapping))
__cleancache_invalidate_inode(mapping);
}
static inline void cleancache_invalidate_fs(struct super_block *sb)
{
if (cleancache_enabled)
__cleancache_invalidate_fs(sb);
}
#endif /* _LINUX_CLEANCACHE_H */