[linux-2.6-block.git] / fs / cachefiles / internal.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* General netfs cache on cache files internal defs
 *
 * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#ifdef pr_fmt
#undef pr_fmt
#endif

#define pr_fmt(fmt) "CacheFiles: " fmt


#include <linux/fscache-cache.h>
#include <linux/cred.h>
#include <linux/security.h>
#include <linux/xarray.h>
#include <linux/cachefiles.h>

#define CACHEFILES_DIO_BLOCK_SIZE 4096

struct cachefiles_cache;
struct cachefiles_object;

enum cachefiles_content {
	/* These values are saved on disk */
	CACHEFILES_CONTENT_NO_DATA	= 0, /* No content stored */
	CACHEFILES_CONTENT_SINGLE	= 1, /* Content is monolithic, all is present */
	CACHEFILES_CONTENT_ALL		= 2, /* Content is all present, no map */
	CACHEFILES_CONTENT_BACKFS_MAP	= 3, /* Content is piecemeal, mapped through backing fs */
	CACHEFILES_CONTENT_DIRTY	= 4, /* Content is dirty (only seen on disk) */
	nr__cachefiles_content
};

/*
 * Cached volume representation.
 */
struct cachefiles_volume {
	struct cachefiles_cache		*cache;
	struct list_head		cache_link;	/* Link in cache->volumes */
	struct fscache_volume		*vcookie;	/* The netfs's representation */
	struct dentry			*dentry;	/* The volume dentry */
	struct dentry			*fanout[256];	/* Fanout subdirs */
};

enum cachefiles_object_state {
	CACHEFILES_ONDEMAND_OBJSTATE_CLOSE, /* Anonymous fd closed by daemon or initial state */
	CACHEFILES_ONDEMAND_OBJSTATE_OPEN, /* Anonymous fd associated with object is available */
	CACHEFILES_ONDEMAND_OBJSTATE_REOPENING, /* Object that was closed and is being reopened. */
};

struct cachefiles_ondemand_info {
	struct work_struct		ondemand_work;
	int				ondemand_id;
	enum cachefiles_object_state	state;
	struct cachefiles_object	*object;
	spinlock_t			lock;
};

/*
 * Backing file state.
 */
struct cachefiles_object {
	struct fscache_cookie		*cookie;	/* Netfs data storage object cookie */
	struct cachefiles_volume	*volume;	/* Cache volume that holds this object */
	struct list_head		cache_link;	/* Link in cache->*_list */
	struct file			*file;		/* The file representing this object */
	char				*d_name;	/* Backing file name */
	int				debug_id;
	spinlock_t			lock;
	refcount_t			ref;
	u8				d_name_len;	/* Length of filename */
	enum cachefiles_content		content_info:8;	/* Info about content presence */
	unsigned long			flags;
#define CACHEFILES_OBJECT_USING_TMPFILE	0		/* Have an unlinked tmpfile */
#ifdef CONFIG_CACHEFILES_ONDEMAND
	struct cachefiles_ondemand_info	*ondemand;
#endif
};

#define CACHEFILES_ONDEMAND_ID_CLOSED	-1

/*
 * Cache files cache definition
 */
struct cachefiles_cache {
	struct fscache_cache		*cache;		/* Cache cookie */
	struct vfsmount			*mnt;		/* mountpoint holding the cache */
	struct dentry			*store;		/* Directory into which live objects go */
	struct dentry			*graveyard;	/* directory into which dead objects go */
	struct file			*cachefilesd;	/* manager daemon handle */
	struct list_head		volumes;	/* List of volume objects */
	struct list_head		object_list;	/* List of active objects */
	spinlock_t			object_list_lock; /* Lock for volumes and object_list */
	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 */
	atomic_t			gravecounter;	/* graveyard uniquifier */
	atomic_t			f_released;	/* number of objects released lately */
	atomic_long_t			b_released;	/* number of blocks released lately */
	atomic_long_t			b_writing;	/* Number of blocks being written */
	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;		/* ilog2(bsize) */
	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) */
#define CACHEFILES_ONDEMAND_MODE	4	/* T if in on-demand read mode */
	char				*rootdirname;	/* name of cache root directory */
	char				*secctx;	/* LSM security context */
	char				*tag;		/* cache binding tag */
	refcount_t			unbind_pincount;/* refcount to do daemon unbind */
	struct xarray			reqs;		/* xarray of pending on-demand requests */
	unsigned long			req_id_next;
	struct xarray			ondemand_ids;	/* xarray for ondemand_id allocation */
	u32				ondemand_id_next;
};

static inline bool cachefiles_in_ondemand_mode(struct cachefiles_cache *cache)
{
	return IS_ENABLED(CONFIG_CACHEFILES_ONDEMAND) &&
		test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags);
}

struct cachefiles_req {
	struct cachefiles_object *object;
	struct completion done;
	refcount_t ref;
	int error;
	struct cachefiles_msg msg;
};

#define CACHEFILES_REQ_NEW	XA_MARK_1

#include <trace/events/cachefiles.h>

static inline
struct file *cachefiles_cres_file(struct netfs_cache_resources *cres)
{
	return cres->cache_priv2;
}

static inline
struct cachefiles_object *cachefiles_cres_object(struct netfs_cache_resources *cres)
{
	return fscache_cres_cookie(cres)->cache_priv;
}

/*
 * 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);
}

/*
 * cache.c
 */
extern int cachefiles_add_cache(struct cachefiles_cache *cache);
extern void cachefiles_withdraw_cache(struct cachefiles_cache *cache);

enum cachefiles_has_space_for {
	cachefiles_has_space_check,
	cachefiles_has_space_for_write,
	cachefiles_has_space_for_create,
};
extern int cachefiles_has_space(struct cachefiles_cache *cache,
				unsigned fnr, unsigned bnr,
				enum cachefiles_has_space_for reason);

/*
 * daemon.c
 */
extern const struct file_operations cachefiles_daemon_fops;
extern void cachefiles_flush_reqs(struct cachefiles_cache *cache);
extern void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache);
extern void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache);

/*
 * error_inject.c
 */
#ifdef CONFIG_CACHEFILES_ERROR_INJECTION
extern unsigned int cachefiles_error_injection_state;
extern int cachefiles_register_error_injection(void);
extern void cachefiles_unregister_error_injection(void);

#else
#define cachefiles_error_injection_state 0

static inline int cachefiles_register_error_injection(void)
{
	return 0;
}

static inline void cachefiles_unregister_error_injection(void)
{
}
#endif


static inline int cachefiles_inject_read_error(void)
{
	return cachefiles_error_injection_state & 2 ? -EIO : 0;
}

static inline int cachefiles_inject_write_error(void)
{
	return cachefiles_error_injection_state & 2 ? -EIO :
		cachefiles_error_injection_state & 1 ? -ENOSPC :
		0;
}

static inline int cachefiles_inject_remove_error(void)
{
	return cachefiles_error_injection_state & 2 ? -EIO : 0;
}

/*
 * interface.c
 */
extern const struct fscache_cache_ops cachefiles_cache_ops;
extern void cachefiles_see_object(struct cachefiles_object *object,
				  enum cachefiles_obj_ref_trace why);
extern struct cachefiles_object *cachefiles_grab_object(struct cachefiles_object *object,
							enum cachefiles_obj_ref_trace why);
extern void cachefiles_put_object(struct cachefiles_object *object,
				  enum cachefiles_obj_ref_trace why);

/*
 * io.c
 */
extern bool cachefiles_begin_operation(struct netfs_cache_resources *cres,
				       enum fscache_want_state want_state);
extern int __cachefiles_prepare_write(struct cachefiles_object *object,
				      struct file *file,
				      loff_t *_start, size_t *_len, size_t upper_len,
				      bool no_space_allocated_yet);
extern int __cachefiles_write(struct cachefiles_object *object,
			      struct file *file,
			      loff_t start_pos,
			      struct iov_iter *iter,
			      netfs_io_terminated_t term_func,
			      void *term_func_priv);

/*
 * key.c
 */
extern bool cachefiles_cook_key(struct cachefiles_object *object);

/*
 * main.c
 */
extern struct kmem_cache *cachefiles_object_jar;

/*
 * namei.c
 */
extern void cachefiles_unmark_inode_in_use(struct cachefiles_object *object,
					   struct file *file);
extern int cachefiles_bury_object(struct cachefiles_cache *cache,
				  struct cachefiles_object *object,
				  struct dentry *dir,
				  struct dentry *rep,
				  enum fscache_why_object_killed why);
extern int cachefiles_delete_object(struct cachefiles_object *object,
				    enum fscache_why_object_killed why);
extern bool cachefiles_look_up_object(struct cachefiles_object *object);
extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
					       struct dentry *dir,
					       const char *name,
					       bool *_is_new);
extern void cachefiles_put_directory(struct dentry *dir);

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);
extern struct file *cachefiles_create_tmpfile(struct cachefiles_object *object);
extern bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache,
				      struct cachefiles_object *object);

/*
 * ondemand.c
 */
#ifdef CONFIG_CACHEFILES_ONDEMAND
extern ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
					char __user *_buffer, size_t buflen);

extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache,
				     char *args);

extern int cachefiles_ondemand_restore(struct cachefiles_cache *cache,
					char *args);

extern int cachefiles_ondemand_init_object(struct cachefiles_object *object);
extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object);

extern int cachefiles_ondemand_read(struct cachefiles_object *object,
				    loff_t pos, size_t len);

extern int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj,
					struct cachefiles_volume *volume);
extern void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj);

#define CACHEFILES_OBJECT_STATE_FUNCS(_state, _STATE)	\
static inline bool								\
cachefiles_ondemand_object_is_##_state(const struct cachefiles_object *object) \
{												\
	return object->ondemand->state == CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \
}												\
												\
static inline void								\
cachefiles_ondemand_set_object_##_state(struct cachefiles_object *object) \
{												\
	object->ondemand->state = CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \
}

CACHEFILES_OBJECT_STATE_FUNCS(open, OPEN);
CACHEFILES_OBJECT_STATE_FUNCS(close, CLOSE);
CACHEFILES_OBJECT_STATE_FUNCS(reopening, REOPENING);

static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req)
{
	return cachefiles_ondemand_object_is_reopening(req->object) &&
			req->msg.opcode == CACHEFILES_OP_READ;
}

#else
static inline ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
					char __user *_buffer, size_t buflen)
{
	return -EOPNOTSUPP;
}

static inline int cachefiles_ondemand_init_object(struct cachefiles_object *object)
{
	return 0;
}

static inline void cachefiles_ondemand_clean_object(struct cachefiles_object *object)
{
}

static inline int cachefiles_ondemand_read(struct cachefiles_object *object,
					   loff_t pos, size_t len)
{
	return -EOPNOTSUPP;
}

static inline int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj,
						struct cachefiles_volume *volume)
{
	return 0;
}
static inline void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj)
{
}

static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req)
{
	return false;
}
#endif

/*
 * 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);
}

/*
 * volume.c
 */
void cachefiles_acquire_volume(struct fscache_volume *volume);
void cachefiles_free_volume(struct fscache_volume *volume);
void cachefiles_withdraw_volume(struct cachefiles_volume *volume);

/*
 * xattr.c
 */
extern int cachefiles_set_object_xattr(struct cachefiles_object *object);
extern int cachefiles_check_auxdata(struct cachefiles_object *object,
				    struct file *file);
extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
					  struct cachefiles_object *object,
					  struct dentry *dentry);
extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie);
extern bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume);
extern int cachefiles_check_volume_xattr(struct cachefiles_volume *volume);

/*
 * 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);	\
	if (cachefiles_in_ondemand_mode(___cache))	\
		cachefiles_flush_reqs(___cache);	\
} while (0)

#define cachefiles_io_error_obj(object, FMT, ...)			\
do {									\
	struct cachefiles_cache *___cache;				\
									\
	___cache = (object)->volume->cache;				\
	cachefiles_io_error(___cache, FMT " [o=%08x]", ##__VA_ARGS__,	\
			    (object)->debug_id);			\
} while (0)


/*
 * Debug tracing
 */
extern unsigned cachefiles_debug;
#define CACHEFILES_DEBUG_KENTER	1
#define CACHEFILES_DEBUG_KLEAVE	2
#define CACHEFILES_DEBUG_KDEBUG	4

#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
Commit	Line	Data
77443f61 DH	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
	2	/* General netfs cache on cache files internal defs
	3	*
	4	* Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
	6	*/
	7
	8	#ifdef pr_fmt
	9	#undef pr_fmt
	10	#endif
	11
	12	#define pr_fmt(fmt) "CacheFiles: " fmt
	13
	14
	15	#include <linux/fscache-cache.h>
	16	#include <linux/cred.h>
	17	#include <linux/security.h>
c8383054 JX	18	#include <linux/xarray.h>
c8383054 JX	19	#include <linux/cachefiles.h>
77443f61	20
1f08c925 DH	21	#define CACHEFILES_DIO_BLOCK_SIZE 4096
1f08c925 DH	22
8390fbc4 DH	23	struct cachefiles_cache;
	24	struct cachefiles_object;
	25
df98e87f DH	26	enum cachefiles_content {
	27	/* These values are saved on disk */
	28	CACHEFILES_CONTENT_NO_DATA = 0, /* No content stored */
	29	CACHEFILES_CONTENT_SINGLE = 1, /* Content is monolithic, all is present */
	30	CACHEFILES_CONTENT_ALL = 2, /* Content is all present, no map */
	31	CACHEFILES_CONTENT_BACKFS_MAP = 3, /* Content is piecemeal, mapped through backing fs */
	32	CACHEFILES_CONTENT_DIRTY = 4, /* Content is dirty (only seen on disk) */
	33	nr__cachefiles_content
	34	};
	35
fe2140e2 DH	36	/*
	37	* Cached volume representation.
	38	*/
	39	struct cachefiles_volume {
	40	struct cachefiles_cache *cache;
	41	struct list_head cache_link; /* Link in cache->volumes */
	42	struct fscache_volume vcookie; / The netfs's representation */
	43	struct dentry dentry; / The volume dentry */
	44	struct dentry fanout[256]; / Fanout subdirs */
	45	};
	46
357a18d0 JZ	47	enum cachefiles_object_state {
	48	CACHEFILES_ONDEMAND_OBJSTATE_CLOSE, /* Anonymous fd closed by daemon or initial state */
	49	CACHEFILES_ONDEMAND_OBJSTATE_OPEN, /* Anonymous fd associated with object is available */
0a7e54c1	50	CACHEFILES_ONDEMAND_OBJSTATE_REOPENING, /* Object that was closed and is being reopened. */
357a18d0 JZ	51	};
357a18d0 JZ	52
3c5ecfe1	53	struct cachefiles_ondemand_info {
0a7e54c1	54	struct work_struct ondemand_work;
3c5ecfe1 JZ	55	int ondemand_id;
	56	enum cachefiles_object_state state;
	57	struct cachefiles_object *object;
0a790040	58	spinlock_t lock;
3c5ecfe1 JZ	59	};
3c5ecfe1 JZ	60
8390fbc4	61	/*
df98e87f	62	* Backing file state.
8390fbc4 DH	63	*/
8390fbc4 DH	64	struct cachefiles_object {
df98e87f DH	65	struct fscache_cookie cookie; / Netfs data storage object cookie */
	66	struct cachefiles_volume volume; / Cache volume that holds this object */
	67	struct list_head cache_link; /* Link in cache->_list /
	68	struct file file; / The file representing this object */
	69	char d_name; / Backing file name */
	70	int debug_id;
	71	spinlock_t lock;
	72	refcount_t ref;
	73	u8 d_name_len; /* Length of filename */
	74	enum cachefiles_content content_info:8; /* Info about content presence */
	75	unsigned long flags;
72b95785	76	#define CACHEFILES_OBJECT_USING_TMPFILE 0 /* Have an unlinked tmpfile */
c8383054	77	#ifdef CONFIG_CACHEFILES_ONDEMAND
3c5ecfe1	78	struct cachefiles_ondemand_info *ondemand;
c8383054	79	#endif
8390fbc4 DH	80	};
8390fbc4 DH	81
c8383054 JX	82	#define CACHEFILES_ONDEMAND_ID_CLOSED -1
c8383054 JX	83
8390fbc4 DH	84	/*
	85	* Cache files cache definition
	86	*/
	87	struct cachefiles_cache {
1493bf74	88	struct fscache_cache cache; / Cache cookie */
8390fbc4	89	struct vfsmount mnt; / mountpoint holding the cache */
d1065b0a DH	90	struct dentry store; / Directory into which live objects go */
d1065b0a DH	91	struct dentry graveyard; / directory into which dead objects go */
8390fbc4	92	struct file cachefilesd; / manager daemon handle */
fe2140e2	93	struct list_head volumes; /* List of volume objects */
1f08c925	94	struct list_head object_list; /* List of active objects */
fe2140e2	95	spinlock_t object_list_lock; /* Lock for volumes and object_list */
8390fbc4 DH	96	const struct cred cache_cred; / security override for accessing cache */
	97	struct mutex daemon_mutex; /* command serialisation mutex */
	98	wait_queue_head_t daemon_pollwq; /* poll waitqueue for daemon */
	99	atomic_t gravecounter; /* graveyard uniquifier */
	100	atomic_t f_released; /* number of objects released lately */
	101	atomic_long_t b_released; /* number of blocks released lately */
80f94f29	102	atomic_long_t b_writing; /* Number of blocks being written */
8390fbc4 DH	103	unsigned frun_percent; /* when to stop culling (% files) */
	104	unsigned fcull_percent; /* when to start culling (% files) */
	105	unsigned fstop_percent; /* when to stop allocating (% files) */
	106	unsigned brun_percent; /* when to stop culling (% blocks) */
	107	unsigned bcull_percent; /* when to start culling (% blocks) */
	108	unsigned bstop_percent; /* when to stop allocating (% blocks) */
	109	unsigned bsize; /* cache's block size */
5638b067	110	unsigned bshift; /* ilog2(bsize) */
8390fbc4 DH	111	uint64_t frun; /* when to stop culling */
	112	uint64_t fcull; /* when to start culling */
	113	uint64_t fstop; /* when to stop allocating */
	114	sector_t brun; /* when to stop culling */
	115	sector_t bcull; /* when to start culling */
	116	sector_t bstop; /* when to stop allocating */
	117	unsigned long flags;
	118	#define CACHEFILES_READY 0 /* T if cache prepared */
	119	#define CACHEFILES_DEAD 1 /* T if cache dead */
	120	#define CACHEFILES_CULLING 2 /* T if cull engaged */
	121	#define CACHEFILES_STATE_CHANGED 3 /* T if state changed (poll trigger) */
c8383054	122	#define CACHEFILES_ONDEMAND_MODE 4 /* T if in on-demand read mode */
8390fbc4 DH	123	char rootdirname; / name of cache root directory */
	124	char secctx; / LSM security context */
	125	char tag; / cache binding tag */
d11b0b04	126	refcount_t unbind_pincount;/* refcount to do daemon unbind */
c8383054	127	struct xarray reqs; /* xarray of pending on-demand requests */
1122f400	128	unsigned long req_id_next;
c8383054 JX	129	struct xarray ondemand_ids; /* xarray for ondemand_id allocation */
c8383054 JX	130	u32 ondemand_id_next;
8390fbc4 DH	131	};
8390fbc4 DH	132
c8383054 JX	133	static inline bool cachefiles_in_ondemand_mode(struct cachefiles_cache *cache)
	134	{
	135	return IS_ENABLED(CONFIG_CACHEFILES_ONDEMAND) &&
	136	test_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags);
	137	}
	138
	139	struct cachefiles_req {
	140	struct cachefiles_object *object;
	141	struct completion done;
de3e26f9	142	refcount_t ref;
c8383054 JX	143	int error;
	144	struct cachefiles_msg msg;
	145	};
	146
	147	#define CACHEFILES_REQ_NEW XA_MARK_1
	148
ecf5a6ce	149	#include <trace/events/cachefiles.h>
77443f61	150
287fd611 DH	151	static inline
	152	struct file cachefiles_cres_file(struct netfs_cache_resources cres)
	153	{
	154	return cres->cache_priv2;
	155	}
	156
	157	static inline
	158	struct cachefiles_object cachefiles_cres_object(struct netfs_cache_resources cres)
	159	{
	160	return fscache_cres_cookie(cres)->cache_priv;
	161	}
	162
8667d434 DH	163	/*
	164	* note change of state for daemon
	165	*/
	166	static inline void cachefiles_state_changed(struct cachefiles_cache *cache)
	167	{
	168	set_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
	169	wake_up_all(&cache->daemon_pollwq);
	170	}
	171
80f94f29 DH	172	/*
	173	* cache.c
	174	*/
d1065b0a	175	extern int cachefiles_add_cache(struct cachefiles_cache *cache);
d1065b0a	176	extern void cachefiles_withdraw_cache(struct cachefiles_cache *cache);
80f94f29	177
3929eca7 DH	178	enum cachefiles_has_space_for {
	179	cachefiles_has_space_check,
	180	cachefiles_has_space_for_write,
	181	cachefiles_has_space_for_create,
	182	};
	183	extern int cachefiles_has_space(struct cachefiles_cache *cache,
	184	unsigned fnr, unsigned bnr,
	185	enum cachefiles_has_space_for reason);
	186
8667d434 DH	187	/*
	188	* daemon.c
	189	*/
	190	extern const struct file_operations cachefiles_daemon_fops;
85e833cd	191	extern void cachefiles_flush_reqs(struct cachefiles_cache *cache);
d11b0b04 JX	192	extern void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache);
d11b0b04 JX	193	extern void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache);
8667d434	194
77443f61	195	/*
a70f6526 DH	196	* error_inject.c
	197	*/
	198	#ifdef CONFIG_CACHEFILES_ERROR_INJECTION
	199	extern unsigned int cachefiles_error_injection_state;
	200	extern int cachefiles_register_error_injection(void);
	201	extern void cachefiles_unregister_error_injection(void);
	202
	203	#else
	204	#define cachefiles_error_injection_state 0
	205
	206	static inline int cachefiles_register_error_injection(void)
	207	{
	208	return 0;
	209	}
	210
	211	static inline void cachefiles_unregister_error_injection(void)
	212	{
	213	}
	214	#endif
	215
	216
	217	static inline int cachefiles_inject_read_error(void)
	218	{
	219	return cachefiles_error_injection_state & 2 ? -EIO : 0;
	220	}
	221
	222	static inline int cachefiles_inject_write_error(void)
	223	{
	224	return cachefiles_error_injection_state & 2 ? -EIO :
	225	cachefiles_error_injection_state & 1 ? -ENOSPC :
	226	0;
	227	}
	228
	229	static inline int cachefiles_inject_remove_error(void)
	230	{
	231	return cachefiles_error_injection_state & 2 ? -EIO : 0;
	232	}
	233
d1065b0a DH	234	/*
	235	* interface.c
	236	*/
	237	extern const struct fscache_cache_ops cachefiles_cache_ops;
df98e87f DH	238	extern void cachefiles_see_object(struct cachefiles_object *object,
	239	enum cachefiles_obj_ref_trace why);
	240	extern struct cachefiles_object cachefiles_grab_object(struct cachefiles_object object,
	241	enum cachefiles_obj_ref_trace why);
	242	extern void cachefiles_put_object(struct cachefiles_object *object,
	243	enum cachefiles_obj_ref_trace why);
	244
287fd611 DH	245	/*
	246	* io.c
	247	*/
	248	extern bool cachefiles_begin_operation(struct netfs_cache_resources *cres,
	249	enum fscache_want_state want_state);
a06fac15 JX	250	extern int __cachefiles_prepare_write(struct cachefiles_object *object,
a06fac15 JX	251	struct file *file,
e0ace6ca	252	loff_t _start, size_t _len, size_t upper_len,
a06fac15 JX	253	bool no_space_allocated_yet);
	254	extern int __cachefiles_write(struct cachefiles_object *object,
	255	struct file *file,
	256	loff_t start_pos,
	257	struct iov_iter *iter,
	258	netfs_io_terminated_t term_func,
	259	void *term_func_priv);
287fd611	260
5d439467 DH	261	/*
	262	* key.c
	263	*/
	264	extern bool cachefiles_cook_key(struct cachefiles_object *object);
	265
df98e87f DH	266	/*
	267	* main.c
	268	*/
	269	extern struct kmem_cache *cachefiles_object_jar;
d1065b0a	270
32759f7d DH	271	/*
	272	* namei.c
	273	*/
169379ea DH	274	extern void cachefiles_unmark_inode_in_use(struct cachefiles_object *object,
169379ea DH	275	struct file *file);
07a90e97 DH	276	extern int cachefiles_bury_object(struct cachefiles_cache *cache,
	277	struct cachefiles_object *object,
	278	struct dentry *dir,
	279	struct dentry *rep,
	280	enum fscache_why_object_killed why);
1f08c925 DH	281	extern int cachefiles_delete_object(struct cachefiles_object *object,
	282	enum fscache_why_object_killed why);
	283	extern bool cachefiles_look_up_object(struct cachefiles_object *object);
32759f7d DH	284	extern struct dentry cachefiles_get_directory(struct cachefiles_cache cache,
	285	struct dentry *dir,
	286	const char *name,
	287	bool *_is_new);
	288	extern void cachefiles_put_directory(struct dentry *dir);
	289
07a90e97 DH	290	extern int cachefiles_cull(struct cachefiles_cache cache, struct dentry dir,
	291	char *filename);
	292
	293	extern int cachefiles_check_in_use(struct cachefiles_cache *cache,
	294	struct dentry dir, char filename);
1f08c925 DH	295	extern struct file cachefiles_create_tmpfile(struct cachefiles_object object);
	296	extern bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache,
	297	struct cachefiles_object *object);
07a90e97	298
c8383054 JX	299	/*
	300	* ondemand.c
	301	*/
	302	#ifdef CONFIG_CACHEFILES_ONDEMAND
	303	extern ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
	304	char __user *_buffer, size_t buflen);
	305
	306	extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache,
	307	char *args);
	308
e73fa11a JZ	309	extern int cachefiles_ondemand_restore(struct cachefiles_cache *cache,
	310	char *args);
	311
c8383054	312	extern int cachefiles_ondemand_init_object(struct cachefiles_object *object);
324b954a	313	extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object);
c8383054	314
9032b6e8 JX	315	extern int cachefiles_ondemand_read(struct cachefiles_object *object,
	316	loff_t pos, size_t len);
	317
3c5ecfe1 JZ	318	extern int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj,
	319	struct cachefiles_volume *volume);
	320	extern void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj);
	321
357a18d0 JZ	322	#define CACHEFILES_OBJECT_STATE_FUNCS(_state, _STATE) \
	323	static inline bool \
	324	cachefiles_ondemand_object_is_##_state(const struct cachefiles_object *object) \
	325	{ \
3c5ecfe1	326	return object->ondemand->state == CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \
357a18d0 JZ	327	} \
	328	\
	329	static inline void \
	330	cachefiles_ondemand_set_object_##_state(struct cachefiles_object *object) \
	331	{ \
3c5ecfe1	332	object->ondemand->state = CACHEFILES_ONDEMAND_OBJSTATE_##_STATE; \
357a18d0 JZ	333	}
	334
	335	CACHEFILES_OBJECT_STATE_FUNCS(open, OPEN);
	336	CACHEFILES_OBJECT_STATE_FUNCS(close, CLOSE);
0a7e54c1	337	CACHEFILES_OBJECT_STATE_FUNCS(reopening, REOPENING);
b817e22b JZ	338
	339	static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req)
	340	{
	341	return cachefiles_ondemand_object_is_reopening(req->object) &&
	342	req->msg.opcode == CACHEFILES_OP_READ;
	343	}
	344
c8383054 JX	345	#else
	346	static inline ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache,
	347	char __user *_buffer, size_t buflen)
	348	{
	349	return -EOPNOTSUPP;
	350	}
	351
	352	static inline int cachefiles_ondemand_init_object(struct cachefiles_object *object)
	353	{
	354	return 0;
	355	}
324b954a JX	356
	357	static inline void cachefiles_ondemand_clean_object(struct cachefiles_object *object)
	358	{
	359	}
9032b6e8 JX	360
	361	static inline int cachefiles_ondemand_read(struct cachefiles_object *object,
	362	loff_t pos, size_t len)
	363	{
	364	return -EOPNOTSUPP;
	365	}
3c5ecfe1 JZ	366
	367	static inline int cachefiles_ondemand_init_obj_info(struct cachefiles_object *obj,
	368	struct cachefiles_volume *volume)
	369	{
	370	return 0;
	371	}
	372	static inline void cachefiles_ondemand_deinit_obj_info(struct cachefiles_object *obj)
	373	{
	374	}
b817e22b JZ	375
	376	static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req)
	377	{
	378	return false;
	379	}
c8383054 JX	380	#endif
c8383054 JX	381
254947d4 DH	382	/*
	383	* security.c
	384	*/
	385	extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);
	386	extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache,
	387	struct dentry *root,
	388	const struct cred **_saved_cred);
	389
	390	static inline void cachefiles_begin_secure(struct cachefiles_cache *cache,
	391	const struct cred **_saved_cred)
	392	{
	393	*_saved_cred = override_creds(cache->cache_cred);
	394	}
	395
	396	static inline void cachefiles_end_secure(struct cachefiles_cache *cache,
	397	const struct cred *saved_cred)
	398	{
	399	revert_creds(saved_cred);
	400	}
	401
fe2140e2 DH	402	/*
	403	* volume.c
	404	*/
	405	void cachefiles_acquire_volume(struct fscache_volume *volume);
	406	void cachefiles_free_volume(struct fscache_volume *volume);
	407	void cachefiles_withdraw_volume(struct cachefiles_volume *volume);
	408
72b95785 DH	409	/*
	410	* xattr.c
	411	*/
	412	extern int cachefiles_set_object_xattr(struct cachefiles_object *object);
	413	extern int cachefiles_check_auxdata(struct cachefiles_object *object,
	414	struct file *file);
	415	extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
	416	struct cachefiles_object *object,
	417	struct dentry *dentry);
	418	extern void cachefiles_prepare_to_write(struct fscache_cookie *cookie);
32e15003 DH	419	extern bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume);
32e15003 DH	420	extern int cachefiles_check_volume_xattr(struct cachefiles_volume *volume);
72b95785	421
1493bf74 DH	422	/*
	423	* Error handling
	424	*/
	425	#define cachefiles_io_error(___cache, FMT, ...) \
	426	do { \
	427	pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__); \
	428	fscache_io_error((___cache)->cache); \
	429	set_bit(CACHEFILES_DEAD, &(___cache)->flags); \
85e833cd BL	430	if (cachefiles_in_ondemand_mode(___cache)) \
85e833cd BL	431	cachefiles_flush_reqs(___cache); \
1493bf74 DH	432	} while (0)
1493bf74 DH	433
72b95785 DH	434	#define cachefiles_io_error_obj(object, FMT, ...) \
	435	do { \
	436	struct cachefiles_cache *___cache; \
	437	\
	438	___cache = (object)->volume->cache; \
	439	cachefiles_io_error(___cache, FMT " [o=%08x]", ##__VA_ARGS__, \
	440	(object)->debug_id); \
	441	} while (0)
	442
a70f6526 DH	443
	444	/*
	445	* Debug tracing
77443f61 DH	446	*/
	447	extern unsigned cachefiles_debug;
	448	#define CACHEFILES_DEBUG_KENTER 1
	449	#define CACHEFILES_DEBUG_KLEAVE 2
	450	#define CACHEFILES_DEBUG_KDEBUG 4
	451
	452	#define dbgprintk(FMT, ...) \
	453	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
	454
	455	#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	456	#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	457	#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
	458
	459
	460	#if defined(__KDEBUG)
	461	#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
	462	#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
	463	#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
	464
	465	#elif defined(CONFIG_CACHEFILES_DEBUG)
	466	#define _enter(FMT, ...) \
	467	do { \
	468	if (cachefiles_debug & CACHEFILES_DEBUG_KENTER) \
	469	kenter(FMT, ##__VA_ARGS__); \
	470	} while (0)
	471
	472	#define _leave(FMT, ...) \
	473	do { \
	474	if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE) \
	475	kleave(FMT, ##__VA_ARGS__); \
	476	} while (0)
	477
	478	#define _debug(FMT, ...) \
	479	do { \
	480	if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG) \
	481	kdebug(FMT, ##__VA_ARGS__); \
	482	} while (0)
	483
	484	#else
	485	#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	486	#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	487	#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
	488	#endif
	489
	490	#if 1 /* defined(__KDEBUGALL) */
	491
	492	#define ASSERT(X) \
	493	do { \
	494	if (unlikely(!(X))) { \
	495	pr_err("\n"); \
	496	pr_err("Assertion failed\n"); \
	497	BUG(); \
	498	} \
	499	} while (0)
	500
	501	#define ASSERTCMP(X, OP, Y) \
	502	do { \
	503	if (unlikely(!((X) OP (Y)))) { \
	504	pr_err("\n"); \
	505	pr_err("Assertion failed\n"); \
	506	pr_err("%lx " #OP " %lx is false\n", \
	507	(unsigned long)(X), (unsigned long)(Y)); \
	508	BUG(); \
	509	} \
510	} while (0)
511
512	#define ASSERTIF(C, X) \
513	do { \
514	if (unlikely((C) && !(X))) { \
515	pr_err("\n"); \
516	pr_err("Assertion failed\n"); \
517	BUG(); \
518	} \
519	} while (0)
520
521	#define ASSERTIFCMP(C, X, OP, Y) \
522	do { \
523	if (unlikely((C) && !((X) OP (Y)))) { \
524	pr_err("\n"); \
525	pr_err("Assertion failed\n"); \
526	pr_err("%lx " #OP " %lx is false\n", \
527	(unsigned long)(X), (unsigned long)(Y)); \
528	BUG(); \
529	} \
530	} while (0)
531
532	#else
533
534	#define ASSERT(X) do {} while (0)
535	#define ASSERTCMP(X, OP, Y) do {} while (0)
536	#define ASSERTIF(C, X) do {} while (0)
537	#define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
538
539	#endif