[linux-2.6-block.git] / include / uapi / linux / bcache.h

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _LINUX_BCACHE_H
#define _LINUX_BCACHE_H

/*
 * Bcache on disk data structures
 */

#include <linux/types.h>

#define BITMASK(name, type, field, offset, size)		\
static inline __u64 name(const type *k)				\
{ return (k->field >> offset) & ~(~0ULL << size); }		\
								\
static inline void SET_##name(type *k, __u64 v)			\
{								\
	k->field &= ~(~(~0ULL << size) << offset);		\
	k->field |= (v & ~(~0ULL << size)) << offset;		\
}

/* Btree keys - all units are in sectors */

struct bkey {
	__u64	high;
	__u64	low;
	__u64	ptr[];
};

#define KEY_FIELD(name, field, offset, size)				\
	BITMASK(name, struct bkey, field, offset, size)

#define PTR_FIELD(name, offset, size)					\
static inline __u64 name(const struct bkey *k, unsigned int i)		\
{ return (k->ptr[i] >> offset) & ~(~0ULL << size); }			\
									\
static inline void SET_##name(struct bkey *k, unsigned int i, __u64 v)	\
{									\
	k->ptr[i] &= ~(~(~0ULL << size) << offset);			\
	k->ptr[i] |= (v & ~(~0ULL << size)) << offset;			\
}

#define KEY_SIZE_BITS		16
#define KEY_MAX_U64S		8

KEY_FIELD(KEY_PTRS,	high, 60, 3)
KEY_FIELD(HEADER_SIZE,	high, 58, 2)
KEY_FIELD(KEY_CSUM,	high, 56, 2)
KEY_FIELD(KEY_PINNED,	high, 55, 1)
KEY_FIELD(KEY_DIRTY,	high, 36, 1)

KEY_FIELD(KEY_SIZE,	high, 20, KEY_SIZE_BITS)
KEY_FIELD(KEY_INODE,	high, 0,  20)

/* Next time I change the on disk format, KEY_OFFSET() won't be 64 bits */

static inline __u64 KEY_OFFSET(const struct bkey *k)
{
	return k->low;
}

static inline void SET_KEY_OFFSET(struct bkey *k, __u64 v)
{
	k->low = v;
}

/*
 * The high bit being set is a relic from when we used it to do binary
 * searches - it told you where a key started. It's not used anymore,
 * and can probably be safely dropped.
 */
#define KEY(inode, offset, size)					\
((struct bkey) {							\
	.high = (1ULL << 63) | ((__u64) (size) << 20) | (inode),	\
	.low = (offset)							\
})

#define ZERO_KEY			KEY(0, 0, 0)

#define MAX_KEY_INODE			(~(~0 << 20))
#define MAX_KEY_OFFSET			(~0ULL >> 1)
#define MAX_KEY				KEY(MAX_KEY_INODE, MAX_KEY_OFFSET, 0)

#define KEY_START(k)			(KEY_OFFSET(k) - KEY_SIZE(k))
#define START_KEY(k)			KEY(KEY_INODE(k), KEY_START(k), 0)

#define PTR_DEV_BITS			12

PTR_FIELD(PTR_DEV,			51, PTR_DEV_BITS)
PTR_FIELD(PTR_OFFSET,			8,  43)
PTR_FIELD(PTR_GEN,			0,  8)

#define PTR_CHECK_DEV			((1 << PTR_DEV_BITS) - 1)

#define MAKE_PTR(gen, offset, dev)					\
	((((__u64) dev) << 51) | ((__u64) offset) << 8 | gen)

/* Bkey utility code */

static inline unsigned long bkey_u64s(const struct bkey *k)
{
	return (sizeof(struct bkey) / sizeof(__u64)) + KEY_PTRS(k);
}

static inline unsigned long bkey_bytes(const struct bkey *k)
{
	return bkey_u64s(k) * sizeof(__u64);
}

#define bkey_copy(_dest, _src)	memcpy(_dest, _src, bkey_bytes(_src))

static inline void bkey_copy_key(struct bkey *dest, const struct bkey *src)
{
	SET_KEY_INODE(dest, KEY_INODE(src));
	SET_KEY_OFFSET(dest, KEY_OFFSET(src));
}

static inline struct bkey *bkey_next(const struct bkey *k)
{
	__u64 *d = (void *) k;

	return (struct bkey *) (d + bkey_u64s(k));
}

static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys)
{
	__u64 *d = (void *) k;

	return (struct bkey *) (d + nr_keys);
}
/* Enough for a key with 6 pointers */
#define BKEY_PAD		8

#define BKEY_PADDED(key)					\
	union { struct bkey key; __u64 key ## _pad[BKEY_PAD]; }

/* Superblock */

/* Version 0: Cache device
 * Version 1: Backing device
 * Version 2: Seed pointer into btree node checksum
 * Version 3: Cache device with new UUID format
 * Version 4: Backing device with data offset
 */
#define BCACHE_SB_VERSION_CDEV		0
#define BCACHE_SB_VERSION_BDEV		1
#define BCACHE_SB_VERSION_CDEV_WITH_UUID 3
#define BCACHE_SB_VERSION_BDEV_WITH_OFFSET 4
#define BCACHE_SB_MAX_VERSION		4

#define SB_SECTOR			8
#define SB_SIZE				4096
#define SB_LABEL_SIZE			32
#define SB_JOURNAL_BUCKETS		256U
/* SB_JOURNAL_BUCKETS must be divisible by BITS_PER_LONG */
#define MAX_CACHES_PER_SET		8

#define BDEV_DATA_START_DEFAULT		16	/* sectors */

struct cache_sb {
	__u64			csum;
	__u64			offset;	/* sector where this sb was written */
	__u64			version;

	__u8			magic[16];

	__u8			uuid[16];
	union {
		__u8		set_uuid[16];
		__u64		set_magic;
	};
	__u8			label[SB_LABEL_SIZE];

	__u64			flags;
	__u64			seq;
	__u64			pad[8];

	union {
	struct {
		/* Cache devices */
		__u64		nbuckets;	/* device size */

		__u16		block_size;	/* sectors */
		__u16		bucket_size;	/* sectors */

		__u16		nr_in_set;
		__u16		nr_this_dev;
	};
	struct {
		/* Backing devices */
		__u64		data_offset;

		/*
		 * block_size from the cache device section is still used by
		 * backing devices, so don't add anything here until we fix
		 * things to not need it for backing devices anymore
		 */
	};
	};

	__u32			last_mount;	/* time overflow in y2106 */

	__u16			first_bucket;
	union {
		__u16		njournal_buckets;
		__u16		keys;
	};
	__u64			d[SB_JOURNAL_BUCKETS];	/* journal buckets */
};

static inline _Bool SB_IS_BDEV(const struct cache_sb *sb)
{
	return sb->version == BCACHE_SB_VERSION_BDEV
		|| sb->version == BCACHE_SB_VERSION_BDEV_WITH_OFFSET;
}

BITMASK(CACHE_SYNC,			struct cache_sb, flags, 0, 1);
BITMASK(CACHE_DISCARD,			struct cache_sb, flags, 1, 1);
BITMASK(CACHE_REPLACEMENT,		struct cache_sb, flags, 2, 3);
#define CACHE_REPLACEMENT_LRU		0U
#define CACHE_REPLACEMENT_FIFO		1U
#define CACHE_REPLACEMENT_RANDOM	2U

BITMASK(BDEV_CACHE_MODE,		struct cache_sb, flags, 0, 4);
#define CACHE_MODE_WRITETHROUGH		0U
#define CACHE_MODE_WRITEBACK		1U
#define CACHE_MODE_WRITEAROUND		2U
#define CACHE_MODE_NONE			3U
BITMASK(BDEV_STATE,			struct cache_sb, flags, 61, 2);
#define BDEV_STATE_NONE			0U
#define BDEV_STATE_CLEAN		1U
#define BDEV_STATE_DIRTY		2U
#define BDEV_STATE_STALE		3U

/*
 * Magic numbers
 *
 * The various other data structures have their own magic numbers, which are
 * xored with the first part of the cache set's UUID
 */

#define JSET_MAGIC			0x245235c1a3625032ULL
#define PSET_MAGIC			0x6750e15f87337f91ULL
#define BSET_MAGIC			0x90135c78b99e07f5ULL

static inline __u64 jset_magic(struct cache_sb *sb)
{
	return sb->set_magic ^ JSET_MAGIC;
}

static inline __u64 pset_magic(struct cache_sb *sb)
{
	return sb->set_magic ^ PSET_MAGIC;
}

static inline __u64 bset_magic(struct cache_sb *sb)
{
	return sb->set_magic ^ BSET_MAGIC;
}

/*
 * Journal
 *
 * On disk format for a journal entry:
 * seq is monotonically increasing; every journal entry has its own unique
 * sequence number.
 *
 * last_seq is the oldest journal entry that still has keys the btree hasn't
 * flushed to disk yet.
 *
 * version is for on disk format changes.
 */

#define BCACHE_JSET_VERSION_UUIDv1	1
#define BCACHE_JSET_VERSION_UUID	1	/* Always latest UUID format */
#define BCACHE_JSET_VERSION		1

struct jset {
	__u64			csum;
	__u64			magic;
	__u64			seq;
	__u32			version;
	__u32			keys;

	__u64			last_seq;

	BKEY_PADDED(uuid_bucket);
	BKEY_PADDED(btree_root);
	__u16			btree_level;
	__u16			pad[3];

	__u64			prio_bucket[MAX_CACHES_PER_SET];

	union {
		struct bkey	start[0];
		__u64		d[0];
	};
};

/* Bucket prios/gens */

struct prio_set {
	__u64			csum;
	__u64			magic;
	__u64			seq;
	__u32			version;
	__u32			pad;

	__u64			next_bucket;

	struct bucket_disk {
		__u16		prio;
		__u8		gen;
	} __attribute((packed)) data[];
};

/* UUIDS - per backing device/flash only volume metadata */

struct uuid_entry {
	union {
		struct {
			__u8	uuid[16];
			__u8	label[32];
			__u32	first_reg; /* time overflow in y2106 */
			__u32	last_reg;
			__u32	invalidated;

			__u32	flags;
			/* Size of flash only volumes */
			__u64	sectors;
		};

		__u8		pad[128];
	};
};

BITMASK(UUID_FLASH_ONLY,	struct uuid_entry, flags, 0, 1);

/* Btree nodes */

/* Version 1: Seed pointer into btree node checksum
 */
#define BCACHE_BSET_CSUM		1
#define BCACHE_BSET_VERSION		1

/*
 * Btree nodes
 *
 * On disk a btree node is a list/log of these; within each set the keys are
 * sorted
 */
struct bset {
	__u64			csum;
	__u64			magic;
	__u64			seq;
	__u32			version;
	__u32			keys;

	union {
		struct bkey	start[0];
		__u64		d[0];
	};
};

/* OBSOLETE */

/* UUIDS - per backing device/flash only volume metadata */

struct uuid_entry_v0 {
	__u8		uuid[16];
	__u8		label[32];
	__u32		first_reg;
	__u32		last_reg;
	__u32		invalidated;
	__u32		pad;
};

#endif /* _LINUX_BCACHE_H */
Commit	Line	Data
6f52b16c	1	/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
81ab4190 KO	2	#ifndef _LINUX_BCACHE_H
	3	#define _LINUX_BCACHE_H
	4
	5	/*
	6	* Bcache on disk data structures
	7	*/
	8
9078b4ee	9	#include <linux/types.h>
81ab4190 KO	10
	11	#define BITMASK(name, type, field, offset, size) \
	12	static inline __u64 name(const type *k) \
	13	{ return (k->field >> offset) & ~(~0ULL << size); } \
	14	\
	15	static inline void SET_##name(type *k, __u64 v) \
	16	{ \
	17	k->field &= ~(~(~0ULL << size) << offset); \
	18	k->field \|= (v & ~(~0ULL << size)) << offset; \
	19	}
	20
	21	/* Btree keys - all units are in sectors */
	22
	23	struct bkey {
	24	__u64 high;
	25	__u64 low;
	26	__u64 ptr[];
	27	};
	28
	29	#define KEY_FIELD(name, field, offset, size) \
	30	BITMASK(name, struct bkey, field, offset, size)
	31
	32	#define PTR_FIELD(name, offset, size) \
6f10f7d1	33	static inline __u64 name(const struct bkey *k, unsigned int i) \
81ab4190 KO	34	{ return (k->ptr[i] >> offset) & ~(~0ULL << size); } \
81ab4190 KO	35	\
6f10f7d1	36	static inline void SET_##name(struct bkey *k, unsigned int i, __u64 v) \
81ab4190 KO	37	{ \
	38	k->ptr[i] &= ~(~(~0ULL << size) << offset); \
	39	k->ptr[i] \|= (v & ~(~0ULL << size)) << offset; \
	40	}
	41
	42	#define KEY_SIZE_BITS 16
59158fde	43	#define KEY_MAX_U64S 8
81ab4190 KO	44
	45	KEY_FIELD(KEY_PTRS, high, 60, 3)
	46	KEY_FIELD(HEADER_SIZE, high, 58, 2)
	47	KEY_FIELD(KEY_CSUM, high, 56, 2)
	48	KEY_FIELD(KEY_PINNED, high, 55, 1)
	49	KEY_FIELD(KEY_DIRTY, high, 36, 1)
	50
	51	KEY_FIELD(KEY_SIZE, high, 20, KEY_SIZE_BITS)
	52	KEY_FIELD(KEY_INODE, high, 0, 20)
	53
	54	/* Next time I change the on disk format, KEY_OFFSET() won't be 64 bits */
	55
	56	static inline __u64 KEY_OFFSET(const struct bkey *k)
	57	{
	58	return k->low;
	59	}
	60
	61	static inline void SET_KEY_OFFSET(struct bkey *k, __u64 v)
	62	{
	63	k->low = v;
	64	}
	65
	66	/*
	67	* The high bit being set is a relic from when we used it to do binary
	68	* searches - it told you where a key started. It's not used anymore,
	69	* and can probably be safely dropped.
	70	*/
	71	#define KEY(inode, offset, size) \
	72	((struct bkey) { \
	73	.high = (1ULL << 63) \| ((__u64) (size) << 20) \| (inode), \
	74	.low = (offset) \
	75	})
	76
	77	#define ZERO_KEY KEY(0, 0, 0)
	78
	79	#define MAX_KEY_INODE (~(~0 << 20))
	80	#define MAX_KEY_OFFSET (~0ULL >> 1)
	81	#define MAX_KEY KEY(MAX_KEY_INODE, MAX_KEY_OFFSET, 0)
	82
	83	#define KEY_START(k) (KEY_OFFSET(k) - KEY_SIZE(k))
	84	#define START_KEY(k) KEY(KEY_INODE(k), KEY_START(k), 0)
	85
	86	#define PTR_DEV_BITS 12
	87
	88	PTR_FIELD(PTR_DEV, 51, PTR_DEV_BITS)
	89	PTR_FIELD(PTR_OFFSET, 8, 43)
	90	PTR_FIELD(PTR_GEN, 0, 8)
	91
	92	#define PTR_CHECK_DEV ((1 << PTR_DEV_BITS) - 1)
	93
cf33c1ee	94	#define MAKE_PTR(gen, offset, dev) \
81ab4190 KO	95	((((__u64) dev) << 51) \| ((__u64) offset) << 8 \| gen)
	96
	97	/* Bkey utility code */
	98
	99	static inline unsigned long bkey_u64s(const struct bkey *k)
	100	{
	101	return (sizeof(struct bkey) / sizeof(__u64)) + KEY_PTRS(k);
	102	}
	103
	104	static inline unsigned long bkey_bytes(const struct bkey *k)
	105	{
	106	return bkey_u64s(k) * sizeof(__u64);
	107	}
	108
	109	#define bkey_copy(_dest, _src) memcpy(_dest, _src, bkey_bytes(_src))
	110
	111	static inline void bkey_copy_key(struct bkey dest, const struct bkey src)
	112	{
	113	SET_KEY_INODE(dest, KEY_INODE(src));
	114	SET_KEY_OFFSET(dest, KEY_OFFSET(src));
	115	}
	116
	117	static inline struct bkey bkey_next(const struct bkey k)
	118	{
	119	__u64 d = (void ) k;
1fae7cf0	120
81ab4190 KO	121	return (struct bkey *) (d + bkey_u64s(k));
	122	}
	123
6f10f7d1	124	static inline struct bkey bkey_idx(const struct bkey k, unsigned int nr_keys)
81ab4190 KO	125	{
81ab4190 KO	126	__u64 d = (void ) k;
1fae7cf0	127
81ab4190 KO	128	return (struct bkey *) (d + nr_keys);
	129	}
	130	/* Enough for a key with 6 pointers */
	131	#define BKEY_PAD 8
	132
	133	#define BKEY_PADDED(key) \
	134	union { struct bkey key; __u64 key ## _pad[BKEY_PAD]; }
	135
	136	/* Superblock */
	137
	138	/* Version 0: Cache device
	139	* Version 1: Backing device
	140	* Version 2: Seed pointer into btree node checksum
	141	* Version 3: Cache device with new UUID format
	142	* Version 4: Backing device with data offset
	143	*/
	144	#define BCACHE_SB_VERSION_CDEV 0
	145	#define BCACHE_SB_VERSION_BDEV 1
	146	#define BCACHE_SB_VERSION_CDEV_WITH_UUID 3
	147	#define BCACHE_SB_VERSION_BDEV_WITH_OFFSET 4
	148	#define BCACHE_SB_MAX_VERSION 4
	149
	150	#define SB_SECTOR 8
	151	#define SB_SIZE 4096
	152	#define SB_LABEL_SIZE 32
	153	#define SB_JOURNAL_BUCKETS 256U
	154	/* SB_JOURNAL_BUCKETS must be divisible by BITS_PER_LONG */
	155	#define MAX_CACHES_PER_SET 8
	156
	157	#define BDEV_DATA_START_DEFAULT 16 /* sectors */
	158
	159	struct cache_sb {
	160	__u64 csum;
	161	__u64 offset; /* sector where this sb was written */
	162	__u64 version;
	163
	164	__u8 magic[16];
	165
	166	__u8 uuid[16];
	167	union {
	168	__u8 set_uuid[16];
	169	__u64 set_magic;
	170	};
	171	__u8 label[SB_LABEL_SIZE];
	172
	173	__u64 flags;
	174	__u64 seq;
	175	__u64 pad[8];
	176
	177	union {
	178	struct {
	179	/* Cache devices */
	180	__u64 nbuckets; /* device size */
	181
	182	__u16 block_size; /* sectors */
	183	__u16 bucket_size; /* sectors */
	184
	185	__u16 nr_in_set;
	186	__u16 nr_this_dev;
	187	};
	188	struct {
	189	/* Backing devices */
	190	__u64 data_offset;
	191
192	/*
193	* block_size from the cache device section is still used by
194	* backing devices, so don't add anything here until we fix
195	* things to not need it for backing devices anymore
196	*/
197	};
198	};
199
75cbb3f1	200	__u32 last_mount; /* time overflow in y2106 */
81ab4190 KO	201
	202	__u16 first_bucket;
	203	union {
	204	__u16 njournal_buckets;
	205	__u16 keys;
	206	};
	207	__u64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */
	208	};
	209
	210	static inline _Bool SB_IS_BDEV(const struct cache_sb *sb)
	211	{
	212	return sb->version == BCACHE_SB_VERSION_BDEV
	213	\|\| sb->version == BCACHE_SB_VERSION_BDEV_WITH_OFFSET;
	214	}
	215
	216	BITMASK(CACHE_SYNC, struct cache_sb, flags, 0, 1);
	217	BITMASK(CACHE_DISCARD, struct cache_sb, flags, 1, 1);
	218	BITMASK(CACHE_REPLACEMENT, struct cache_sb, flags, 2, 3);
	219	#define CACHE_REPLACEMENT_LRU 0U
	220	#define CACHE_REPLACEMENT_FIFO 1U
	221	#define CACHE_REPLACEMENT_RANDOM 2U
	222
	223	BITMASK(BDEV_CACHE_MODE, struct cache_sb, flags, 0, 4);
	224	#define CACHE_MODE_WRITETHROUGH 0U
	225	#define CACHE_MODE_WRITEBACK 1U
	226	#define CACHE_MODE_WRITEAROUND 2U
	227	#define CACHE_MODE_NONE 3U
	228	BITMASK(BDEV_STATE, struct cache_sb, flags, 61, 2);
	229	#define BDEV_STATE_NONE 0U
	230	#define BDEV_STATE_CLEAN 1U
	231	#define BDEV_STATE_DIRTY 2U
	232	#define BDEV_STATE_STALE 3U
	233
	234	/*
	235	* Magic numbers
	236	*
	237	* The various other data structures have their own magic numbers, which are
	238	* xored with the first part of the cache set's UUID
	239	*/
	240
	241	#define JSET_MAGIC 0x245235c1a3625032ULL
	242	#define PSET_MAGIC 0x6750e15f87337f91ULL
	243	#define BSET_MAGIC 0x90135c78b99e07f5ULL
	244
	245	static inline __u64 jset_magic(struct cache_sb *sb)
	246	{
	247	return sb->set_magic ^ JSET_MAGIC;
	248	}
	249
	250	static inline __u64 pset_magic(struct cache_sb *sb)
	251	{
	252	return sb->set_magic ^ PSET_MAGIC;
	253	}
	254
	255	static inline __u64 bset_magic(struct cache_sb *sb)
	256	{
	257	return sb->set_magic ^ BSET_MAGIC;
	258	}
	259
	260	/*
	261	* Journal
	262	*
	263	* On disk format for a journal entry:
	264	* seq is monotonically increasing; every journal entry has its own unique
265	* sequence number.
266	*
267	* last_seq is the oldest journal entry that still has keys the btree hasn't
268	* flushed to disk yet.
269	*
270	* version is for on disk format changes.
271	*/
272
273	#define BCACHE_JSET_VERSION_UUIDv1 1
274	#define BCACHE_JSET_VERSION_UUID 1 /* Always latest UUID format */
275	#define BCACHE_JSET_VERSION 1
276
277	struct jset {
278	__u64 csum;
279	__u64 magic;
280	__u64 seq;
281	__u32 version;
282	__u32 keys;
283
284	__u64 last_seq;
285
286	BKEY_PADDED(uuid_bucket);
287	BKEY_PADDED(btree_root);
288	__u16 btree_level;
289	__u16 pad[3];
290
291	__u64 prio_bucket[MAX_CACHES_PER_SET];
292
293	union {
294	struct bkey start[0];
295	__u64 d[0];
296	};
297	};
298
299	/* Bucket prios/gens */
300
301	struct prio_set {
302	__u64 csum;
303	__u64 magic;
304	__u64 seq;
305	__u32 version;
306	__u32 pad;
307
308	__u64 next_bucket;
309
310	struct bucket_disk {
311	__u16 prio;
312	__u8 gen;
313	} __attribute((packed)) data[];
314	};
315
316	/* UUIDS - per backing device/flash only volume metadata */
317
318	struct uuid_entry {
319	union {
320	struct {
321	__u8 uuid[16];
322	__u8 label[32];
75cbb3f1	323	__u32 first_reg; /* time overflow in y2106 */
81ab4190 KO	324	__u32 last_reg;
	325	__u32 invalidated;
	326
	327	__u32 flags;
	328	/* Size of flash only volumes */
	329	__u64 sectors;
	330	};
	331
	332	__u8 pad[128];
	333	};
	334	};
	335
	336	BITMASK(UUID_FLASH_ONLY, struct uuid_entry, flags, 0, 1);
	337
	338	/* Btree nodes */
	339
	340	/* Version 1: Seed pointer into btree node checksum
	341	*/
	342	#define BCACHE_BSET_CSUM 1
	343	#define BCACHE_BSET_VERSION 1
	344
	345	/*
	346	* Btree nodes
	347	*
	348	* On disk a btree node is a list/log of these; within each set the keys are
	349	* sorted
	350	*/
	351	struct bset {
	352	__u64 csum;
	353	__u64 magic;
	354	__u64 seq;
	355	__u32 version;
	356	__u32 keys;
	357
	358	union {
	359	struct bkey start[0];
	360	__u64 d[0];
	361	};
	362	};
	363
	364	/* OBSOLETE */
	365
	366	/* UUIDS - per backing device/flash only volume metadata */
	367
	368	struct uuid_entry_v0 {
	369	__u8 uuid[16];
	370	__u8 label[32];
	371	__u32 first_reg;
	372	__u32 last_reg;
	373	__u32 invalidated;
	374	__u32 pad;
	375	};
	376
	377	#endif /* _LINUX_BCACHE_H */