/* 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. */ #ifdef pr_fmt#undef pr_fmt#endif #define pr_fmt(fmt) "CacheFiles: " fmt  #include <linux/fscache-cache.h>#include <linux/timer.h>#include <linux/wait_bit.h>#include <linux/cred.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_RECLAIM | __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 */	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 */	atomic_t			f_released;	/* number of objects released lately */	atomic_long_t			b_released;	/* number of blocks released lately */	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_entry_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 void cachefiles_mark_object_inactive(struct cachefiles_cache *cache,					    struct cachefiles_object *object,					    blkcnt_t i_blocks);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_HISTOGRAMextern 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 inlinevoid 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 cachefiles_io_error(___cache, FMT, ...)		\do {							\	pr_err("I/O Error: " FMT"\n", ##__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))) {						\		pr_err("\n");						\		pr_err("Assertion failed\n");		\		BUG();							\	}								\} while (0) #define ASSERTCMP(X, OP, Y)						\do {									\	if (unlikely(!((X) OP (Y)))) {					\		pr_err("\n");						\		pr_err("Assertion failed\n");		\		pr_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))) {					\		pr_err("\n");						\		pr_err("Assertion failed\n");		\		BUG();							\	}								\} while (0) #define ASSERTIFCMP(C, X, OP, Y)					\do {									\	if (unlikely((C) && !((X) OP (Y)))) {				\		pr_err("\n");						\		pr_err("Assertion failed\n");		\		pr_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