fs/cachefiles/internal.h - kernel/lockdown - Git at Google

 /* General netfs cache on cache files internal defs
  *
  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public Licence
  * as published by the Free Software Foundation; either version
  * 2 of the Licence, or (at your option) any later version.
  */

 #include <linux/fscache-cache.h>
 #include <linux/timer.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 #include <linux/security.h>

 struct cachefiles_cache;
 struct cachefiles_object;

 extern unsigned cachefiles_debug;
 #define CACHEFILES_DEBUG_KENTER	1
 #define CACHEFILES_DEBUG_KLEAVE	2
 #define CACHEFILES_DEBUG_KDEBUG	4

 #define cachefiles_gfp (__GFP_WAIT | __GFP_NORETRY | __GFP_NOMEMALLOC)

 /*
  * node records
  */
 struct cachefiles_object {
 	struct fscache_object		fscache;	/* fscache handle */
 	struct cachefiles_lookup_data	*lookup_data;	/* cached lookup data */
 	struct dentry			*dentry;	/* the file/dir representing this object */
 	struct dentry			*backer;	/* backing file */
 	loff_t				i_size;		/* object size */
 	unsigned long			flags;
 #define CACHEFILES_OBJECT_ACTIVE	0		/* T if marked active */
 #define CACHEFILES_OBJECT_BURIED	1		/* T if preemptively buried */
 	atomic_t			usage;		/* object usage count */
 	uint8_t				type;		/* object type */
 	uint8_t				new;		/* T if object new */
 	spinlock_t			work_lock;
 	struct rb_node			active_node;	/* link in active tree (dentry is key) */
 };

 extern struct kmem_cache *cachefiles_object_jar;

 /*
  * Cache files cache definition
  */
 struct cachefiles_cache {
 	struct fscache_cache		cache;		/* FS-Cache record */
 	struct vfsmount			*mnt;		/* mountpoint holding the cache */
 	struct dentry			*graveyard;	/* directory into which dead objects go */
 	struct file			*cachefilesd;	/* manager daemon handle */
 	const struct cred		*cache_cred;	/* security override for accessing cache */
 	struct mutex			daemon_mutex;	/* command serialisation mutex */
 	wait_queue_head_t		daemon_pollwq;	/* poll waitqueue for daemon */
 	struct rb_root			active_nodes;	/* active nodes (can't be culled) */
 	rwlock_t			active_lock;	/* lock for active_nodes */
 	atomic_t			gravecounter;	/* graveyard uniquifier */
 	unsigned			frun_percent;	/* when to stop culling (% files) */
 	unsigned			fcull_percent;	/* when to start culling (% files) */
 	unsigned			fstop_percent;	/* when to stop allocating (% files) */
 	unsigned			brun_percent;	/* when to stop culling (% blocks) */
 	unsigned			bcull_percent;	/* when to start culling (% blocks) */
 	unsigned			bstop_percent;	/* when to stop allocating (% blocks) */
 	unsigned			bsize;		/* cache's block size */
 	unsigned			bshift;		/* min(ilog2(PAGE_SIZE / bsize), 0) */
 	uint64_t			frun;		/* when to stop culling */
 	uint64_t			fcull;		/* when to start culling */
 	uint64_t			fstop;		/* when to stop allocating */
 	sector_t			brun;		/* when to stop culling */
 	sector_t			bcull;		/* when to start culling */
 	sector_t			bstop;		/* when to stop allocating */
 	unsigned long			flags;
 #define CACHEFILES_READY		0	/* T if cache prepared */
 #define CACHEFILES_DEAD			1	/* T if cache dead */
 #define CACHEFILES_CULLING		2	/* T if cull engaged */
 #define CACHEFILES_STATE_CHANGED	3	/* T if state changed (poll trigger) */
 	char				*rootdirname;	/* name of cache root directory */
 	char				*secctx;	/* LSM security context */
 	char				*tag;		/* cache binding tag */
 };

 /*
  * backing file read tracking
  */
 struct cachefiles_one_read {
 	wait_queue_t			monitor;	/* link into monitored waitqueue */
 	struct page			*back_page;	/* backing file page we're waiting for */
 	struct page			*netfs_page;	/* netfs page we're going to fill */
 	struct fscache_retrieval	*op;		/* retrieval op covering this */
 	struct list_head		op_link;	/* link in op's todo list */
 };

 /*
  * backing file write tracking
  */
 struct cachefiles_one_write {
 	struct page			*netfs_page;	/* netfs page to copy */
 	struct cachefiles_object	*object;
 	struct list_head		obj_link;	/* link in object's lists */
 	fscache_rw_complete_t		end_io_func;
 	void				*context;
 };

 /*
  * auxiliary data xattr buffer
  */
 struct cachefiles_xattr {
 	uint16_t			len;
 	uint8_t				type;
 	uint8_t				data[];
 };

 /*
  * note change of state for daemon
  */
 static inline void cachefiles_state_changed(struct cachefiles_cache *cache)
 {
 	set_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
 	wake_up_all(&cache->daemon_pollwq);
 }

 /*
  * bind.c
  */
 extern int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args);
 extern void cachefiles_daemon_unbind(struct cachefiles_cache *cache);

 /*
  * daemon.c
  */
 extern const struct file_operations cachefiles_daemon_fops;

 extern int cachefiles_has_space(struct cachefiles_cache *cache,
 				unsigned fnr, unsigned bnr);

 /*
  * interface.c
  */
 extern const struct fscache_cache_ops cachefiles_cache_ops;

 /*
  * key.c
  */
 extern char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type);

 /*
  * namei.c
  */
 extern int cachefiles_delete_object(struct cachefiles_cache *cache,
 				    struct cachefiles_object *object);
 extern int cachefiles_walk_to_object(struct cachefiles_object *parent,
 				     struct cachefiles_object *object,
 				     const char *key,
 				     struct cachefiles_xattr *auxdata);
 extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
 					       struct dentry *dir,
 					       const char *name);

 extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir,
 			   char *filename);

 extern int cachefiles_check_in_use(struct cachefiles_cache *cache,
 				   struct dentry *dir, char *filename);

 /*
  * proc.c
  */
 #ifdef CONFIG_CACHEFILES_HISTOGRAM
 extern atomic_t cachefiles_lookup_histogram[HZ];
 extern atomic_t cachefiles_mkdir_histogram[HZ];
 extern atomic_t cachefiles_create_histogram[HZ];

 extern int __init cachefiles_proc_init(void);
 extern void cachefiles_proc_cleanup(void);
 static inline
 void cachefiles_hist(atomic_t histogram[], unsigned long start_jif)
 {
 	unsigned long jif = jiffies - start_jif;
 	if (jif >= HZ)
 		jif = HZ - 1;
 	atomic_inc(&histogram[jif]);
 }

 #else
 #define cachefiles_proc_init()		(0)
 #define cachefiles_proc_cleanup()	do {} while (0)
 #define cachefiles_hist(hist, start_jif) do {} while (0)
 #endif

 /*
  * rdwr.c
  */
 extern int cachefiles_read_or_alloc_page(struct fscache_retrieval *,
 					 struct page *, gfp_t);
 extern int cachefiles_read_or_alloc_pages(struct fscache_retrieval *,
 					  struct list_head *, unsigned *,
 					  gfp_t);
 extern int cachefiles_allocate_page(struct fscache_retrieval *, struct page *,
 				    gfp_t);
 extern int cachefiles_allocate_pages(struct fscache_retrieval *,
 				     struct list_head *, unsigned *, gfp_t);
 extern int cachefiles_write_page(struct fscache_storage *, struct page *);
 extern void cachefiles_uncache_page(struct fscache_object *, struct page *);

 /*
  * security.c
  */
 extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);
 extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache,
 					       struct dentry *root,
 					       const struct cred **_saved_cred);

 static inline void cachefiles_begin_secure(struct cachefiles_cache *cache,
 					   const struct cred **_saved_cred)
 {
 	*_saved_cred = override_creds(cache->cache_cred);
 }

 static inline void cachefiles_end_secure(struct cachefiles_cache *cache,
 					 const struct cred *saved_cred)
 {
 	revert_creds(saved_cred);
 }

 /*
  * xattr.c
  */
 extern int cachefiles_check_object_type(struct cachefiles_object *object);
 extern int cachefiles_set_object_xattr(struct cachefiles_object *object,
 				       struct cachefiles_xattr *auxdata);
 extern int cachefiles_update_object_xattr(struct cachefiles_object *object,
 					  struct cachefiles_xattr *auxdata);
 extern int cachefiles_check_auxdata(struct cachefiles_object *object);
 extern int cachefiles_check_object_xattr(struct cachefiles_object *object,
 					 struct cachefiles_xattr *auxdata);
 extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
 					  struct dentry *dentry);


 /*
  * error handling
  */
 #define kerror(FMT, ...) printk(KERN_ERR "CacheFiles: "FMT"\n", ##__VA_ARGS__)

 #define cachefiles_io_error(___cache, FMT, ...)		\
 do {							\
 	kerror("I/O Error: " FMT, ##__VA_ARGS__);	\
 	fscache_io_error(&(___cache)->cache);		\
 	set_bit(CACHEFILES_DEAD, &(___cache)->flags);	\
 } while (0)

 #define cachefiles_io_error_obj(object, FMT, ...)			\
 do {									\
 	struct cachefiles_cache *___cache;				\
 									\
 	___cache = container_of((object)->fscache.cache,		\
 				struct cachefiles_cache, cache);	\
 	cachefiles_io_error(___cache, FMT, ##__VA_ARGS__);		\
 } while (0)


 /*
  * debug tracing
  */
 #define dbgprintk(FMT, ...) \
 	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)

 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)


 #if defined(__KDEBUG)
 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)

 #elif defined(CONFIG_CACHEFILES_DEBUG)
 #define _enter(FMT, ...)				\
 do {							\
 	if (cachefiles_debug & CACHEFILES_DEBUG_KENTER)	\
 		kenter(FMT, ##__VA_ARGS__);		\
 } while (0)

 #define _leave(FMT, ...)				\
 do {							\
 	if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE)	\
 		kleave(FMT, ##__VA_ARGS__);		\
 } while (0)

 #define _debug(FMT, ...)				\
 do {							\
 	if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG)	\
 		kdebug(FMT, ##__VA_ARGS__);		\
 } while (0)

 #else
 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
 #endif

 #if 1 /* defined(__KDEBUGALL) */

 #define ASSERT(X)							\
 do {									\
 	if (unlikely(!(X))) {						\
 		printk(KERN_ERR "\n");					\
 		printk(KERN_ERR "CacheFiles: Assertion failed\n");	\
 		BUG();							\
 	}								\
 } while (0)

 #define ASSERTCMP(X, OP, Y)						\
 do {									\
 	if (unlikely(!((X) OP (Y)))) {					\
 		printk(KERN_ERR "\n");					\
 		printk(KERN_ERR "CacheFiles: Assertion failed\n");	\
 		printk(KERN_ERR "%lx " #OP " %lx is false\n",		\
 		       (unsigned long)(X), (unsigned long)(Y));		\
 		BUG();							\
 	}								\
 } while (0)

 #define ASSERTIF(C, X)							\
 do {									\
 	if (unlikely((C) && !(X))) {					\
 		printk(KERN_ERR "\n");					\
 		printk(KERN_ERR "CacheFiles: Assertion failed\n");	\
 		BUG();							\
 	}								\
 } while (0)

 #define ASSERTIFCMP(C, X, OP, Y)					\
 do {									\
 	if (unlikely((C) && !((X) OP (Y)))) {				\
 		printk(KERN_ERR "\n");					\
 		printk(KERN_ERR "CacheFiles: Assertion failed\n");	\
 		printk(KERN_ERR "%lx " #OP " %lx is false\n",		\
 		       (unsigned long)(X), (unsigned long)(Y));		\
 		BUG();							\
 	}								\
 } while (0)

 #else

 #define ASSERT(X)			do {} while (0)
 #define ASSERTCMP(X, OP, Y)		do {} while (0)
 #define ASSERTIF(C, X)			do {} while (0)
 #define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)

 #endif
	/* General netfs cache on cache files internal defs
	*
	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	* Written by David Howells (dhowells@redhat.com)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public Licence
	* as published by the Free Software Foundation; either version
	* 2 of the Licence, or (at your option) any later version.
	*/

	#include <linux/fscache-cache.h>
	#include <linux/timer.h>
	#include <linux/wait.h>
	#include <linux/workqueue.h>
	#include <linux/security.h>

	struct cachefiles_cache;
	struct cachefiles_object;

	extern unsigned cachefiles_debug;
	#define CACHEFILES_DEBUG_KENTER 1
	#define CACHEFILES_DEBUG_KLEAVE 2
	#define CACHEFILES_DEBUG_KDEBUG 4

	#define cachefiles_gfp (__GFP_WAIT \| __GFP_NORETRY \| __GFP_NOMEMALLOC)

	/*
	* node records
	*/
	struct cachefiles_object {
	struct fscache_object fscache; /* fscache handle */
	struct cachefiles_lookup_data lookup_data; / cached lookup data */
	struct dentry dentry; / the file/dir representing this object */
	struct dentry backer; / backing file */
	loff_t i_size; /* object size */
	unsigned long flags;
	#define CACHEFILES_OBJECT_ACTIVE 0 /* T if marked active */
	#define CACHEFILES_OBJECT_BURIED 1 /* T if preemptively buried */
	atomic_t usage; /* object usage count */
	uint8_t type; /* object type */
	uint8_t new; /* T if object new */
	spinlock_t work_lock;
	struct rb_node active_node; /* link in active tree (dentry is key) */
	};

	extern struct kmem_cache *cachefiles_object_jar;

	/*
	* Cache files cache definition
	*/
	struct cachefiles_cache {
	struct fscache_cache cache; /* FS-Cache record */
	struct vfsmount mnt; / mountpoint holding the cache */
	struct dentry graveyard; / directory into which dead objects go */
	struct file cachefilesd; / manager daemon handle */
	const struct cred cache_cred; / security override for accessing cache */
	struct mutex daemon_mutex; /* command serialisation mutex */
	wait_queue_head_t daemon_pollwq; /* poll waitqueue for daemon */
	struct rb_root active_nodes; /* active nodes (can't be culled) */
	rwlock_t active_lock; /* lock for active_nodes */
	atomic_t gravecounter; /* graveyard uniquifier */
	unsigned frun_percent; /* when to stop culling (% files) */
	unsigned fcull_percent; /* when to start culling (% files) */
	unsigned fstop_percent; /* when to stop allocating (% files) */
	unsigned brun_percent; /* when to stop culling (% blocks) */
	unsigned bcull_percent; /* when to start culling (% blocks) */
	unsigned bstop_percent; /* when to stop allocating (% blocks) */
	unsigned bsize; /* cache's block size */
	unsigned bshift; /* min(ilog2(PAGE_SIZE / bsize), 0) */
	uint64_t frun; /* when to stop culling */
	uint64_t fcull; /* when to start culling */
	uint64_t fstop; /* when to stop allocating */
	sector_t brun; /* when to stop culling */
	sector_t bcull; /* when to start culling */
	sector_t bstop; /* when to stop allocating */
	unsigned long flags;
	#define CACHEFILES_READY 0 /* T if cache prepared */
	#define CACHEFILES_DEAD 1 /* T if cache dead */
	#define CACHEFILES_CULLING 2 /* T if cull engaged */
	#define CACHEFILES_STATE_CHANGED 3 /* T if state changed (poll trigger) */
	char rootdirname; / name of cache root directory */
	char secctx; / LSM security context */
	char tag; / cache binding tag */
	};

	/*
	* backing file read tracking
	*/
	struct cachefiles_one_read {
	wait_queue_t monitor; /* link into monitored waitqueue */
	struct page back_page; / backing file page we're waiting for */
	struct page netfs_page; / netfs page we're going to fill */
	struct fscache_retrieval op; / retrieval op covering this */
	struct list_head op_link; /* link in op's todo list */
	};

	/*
	* backing file write tracking
	*/
	struct cachefiles_one_write {
	struct page netfs_page; / netfs page to copy */
	struct cachefiles_object *object;
	struct list_head obj_link; /* link in object's lists */
	fscache_rw_complete_t end_io_func;
	void *context;
	};

	/*
	* auxiliary data xattr buffer
	*/
	struct cachefiles_xattr {
	uint16_t len;
	uint8_t type;
	uint8_t data[];
	};

	/*
	* note change of state for daemon
	*/
	static inline void cachefiles_state_changed(struct cachefiles_cache *cache)
	{
	set_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
	wake_up_all(&cache->daemon_pollwq);
	}

	/*
	* bind.c
	*/
	extern int cachefiles_daemon_bind(struct cachefiles_cache cache, char args);
	extern void cachefiles_daemon_unbind(struct cachefiles_cache *cache);

	/*
	* daemon.c
	*/
	extern const struct file_operations cachefiles_daemon_fops;

	extern int cachefiles_has_space(struct cachefiles_cache *cache,
	unsigned fnr, unsigned bnr);

	/*
	* interface.c
	*/
	extern const struct fscache_cache_ops cachefiles_cache_ops;

	/*
	* key.c
	*/
	extern char cachefiles_cook_key(const u8 raw, int keylen, uint8_t type);

	/*
	* namei.c
	*/
	extern int cachefiles_delete_object(struct cachefiles_cache *cache,
	struct cachefiles_object *object);
	extern int cachefiles_walk_to_object(struct cachefiles_object *parent,
	struct cachefiles_object *object,
	const char *key,
	struct cachefiles_xattr *auxdata);
	extern struct dentry cachefiles_get_directory(struct cachefiles_cache cache,
	struct dentry *dir,
	const char *name);

	extern int cachefiles_cull(struct cachefiles_cache cache, struct dentry dir,
	char *filename);

	extern int cachefiles_check_in_use(struct cachefiles_cache *cache,
	struct dentry dir, char filename);

	/*
	* proc.c
	*/
	#ifdef CONFIG_CACHEFILES_HISTOGRAM
	extern atomic_t cachefiles_lookup_histogram[HZ];
	extern atomic_t cachefiles_mkdir_histogram[HZ];
	extern atomic_t cachefiles_create_histogram[HZ];

	extern int __init cachefiles_proc_init(void);
	extern void cachefiles_proc_cleanup(void);
	static inline
	void cachefiles_hist(atomic_t histogram[], unsigned long start_jif)
	{
	unsigned long jif = jiffies - start_jif;
	if (jif >= HZ)
	jif = HZ - 1;
	atomic_inc(&histogram[jif]);
	}

	#else
	#define cachefiles_proc_init() (0)
	#define cachefiles_proc_cleanup() do {} while (0)
	#define cachefiles_hist(hist, start_jif) do {} while (0)
	#endif

	/*
	* rdwr.c
	*/
	extern int cachefiles_read_or_alloc_page(struct fscache_retrieval *,
	struct page *, gfp_t);
	extern int cachefiles_read_or_alloc_pages(struct fscache_retrieval *,
	struct list_head , unsigned ,
	gfp_t);
	extern int cachefiles_allocate_page(struct fscache_retrieval , struct page ,
	gfp_t);
	extern int cachefiles_allocate_pages(struct fscache_retrieval *,
	struct list_head , unsigned , gfp_t);
	extern int cachefiles_write_page(struct fscache_storage , struct page );
	extern void cachefiles_uncache_page(struct fscache_object , struct page );

	/*
	* security.c
	*/
	extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);
	extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache,
	struct dentry *root,
	const struct cred **_saved_cred);

	static inline void cachefiles_begin_secure(struct cachefiles_cache *cache,
	const struct cred **_saved_cred)
	{
	*_saved_cred = override_creds(cache->cache_cred);
	}

	static inline void cachefiles_end_secure(struct cachefiles_cache *cache,
	const struct cred *saved_cred)
	{
	revert_creds(saved_cred);
	}

	/*
	* xattr.c
	*/
	extern int cachefiles_check_object_type(struct cachefiles_object *object);
	extern int cachefiles_set_object_xattr(struct cachefiles_object *object,
	struct cachefiles_xattr *auxdata);
	extern int cachefiles_update_object_xattr(struct cachefiles_object *object,
	struct cachefiles_xattr *auxdata);
	extern int cachefiles_check_auxdata(struct cachefiles_object *object);
	extern int cachefiles_check_object_xattr(struct cachefiles_object *object,
	struct cachefiles_xattr *auxdata);
	extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
	struct dentry *dentry);


	/*
	* error handling
	*/
	#define kerror(FMT, ...) printk(KERN_ERR "CacheFiles: "FMT"\n", ##__VA_ARGS__)

	#define cachefiles_io_error(___cache, FMT, ...) \
	do { \
	kerror("I/O Error: " FMT, ##__VA_ARGS__); \
	fscache_io_error(&(___cache)->cache); \
	set_bit(CACHEFILES_DEAD, &(___cache)->flags); \
	} while (0)

	#define cachefiles_io_error_obj(object, FMT, ...) \
	do { \
	struct cachefiles_cache *___cache; \
	\
	___cache = container_of((object)->fscache.cache, \
	struct cachefiles_cache, cache); \
	cachefiles_io_error(___cache, FMT, ##__VA_ARGS__); \
	} while (0)


	/*
	* debug tracing
	*/
	#define dbgprintk(FMT, ...) \
	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)

	#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)


	#if defined(__KDEBUG)
	#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
	#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
	#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)

	#elif defined(CONFIG_CACHEFILES_DEBUG)
	#define _enter(FMT, ...) \
	do { \
	if (cachefiles_debug & CACHEFILES_DEBUG_KENTER) \
	kenter(FMT, ##__VA_ARGS__); \
	} while (0)

	#define _leave(FMT, ...) \
	do { \
	if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE) \
	kleave(FMT, ##__VA_ARGS__); \
	} while (0)

	#define _debug(FMT, ...) \
	do { \
	if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG) \
	kdebug(FMT, ##__VA_ARGS__); \
	} while (0)

	#else
	#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
	#endif

	#if 1 /* defined(__KDEBUGALL) */

	#define ASSERT(X) \
	do { \
	if (unlikely(!(X))) { \
	printk(KERN_ERR "\n"); \
	printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
	BUG(); \
	} \
	} while (0)

	#define ASSERTCMP(X, OP, Y) \
	do { \
	if (unlikely(!((X) OP (Y)))) { \
	printk(KERN_ERR "\n"); \
	printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
	printk(KERN_ERR "%lx " #OP " %lx is false\n", \
	(unsigned long)(X), (unsigned long)(Y)); \
	BUG(); \
	} \
	} while (0)

	#define ASSERTIF(C, X) \
	do { \
	if (unlikely((C) && !(X))) { \
	printk(KERN_ERR "\n"); \
	printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
	BUG(); \
	} \
	} while (0)

	#define ASSERTIFCMP(C, X, OP, Y) \
	do { \
	if (unlikely((C) && !((X) OP (Y)))) { \
	printk(KERN_ERR "\n"); \
	printk(KERN_ERR "CacheFiles: Assertion failed\n"); \
	printk(KERN_ERR "%lx " #OP " %lx is false\n", \
	(unsigned long)(X), (unsigned long)(Y)); \
	BUG(); \
	} \
	} while (0)

	#else

	#define ASSERT(X) do {} while (0)
	#define ASSERTCMP(X, OP, Y) do {} while (0)
	#define ASSERTIF(C, X) do {} while (0)
	#define ASSERTIFCMP(C, X, OP, Y) do {} while (0)

	#endif