/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

#ifndef	_SYS_ZAP_IMPL_H

#define	_SYS_ZAP_IMPL_H

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/zap.h>

#include <sys/zfs_context.h>

#include <sys/avl.h>

#ifdef	__cplusplus

extern "C" {

#endif

extern int fzap_default_block_shift;

#define	ZAP_MAGIC 0x2F52AB2AB

#define	FZAP_BLOCK_SHIFT(zap)	((zap)->zap_f.zap_block_shift)

#define	ZAP_MAXCD		(uint32_t)(-1)

#define	ZAP_HASHBITS		28

#define	MZAP_ENT_LEN		64

#define	MZAP_NAME_LEN		(MZAP_ENT_LEN - 8 - 4 - 2)

#define	MZAP_MAX_BLKSHIFT	SPA_MAXBLOCKSHIFT

#define	MZAP_MAX_BLKSZ		(1 << MZAP_MAX_BLKSHIFT)

typedef struct mzap_ent_phys {

	uint64_t mze_value;

	uint32_t mze_cd;

	uint16_t mze_pad;	/* in case we want to chain them someday */

	char mze_name[MZAP_NAME_LEN];

} mzap_ent_phys_t;

typedef struct mzap_phys {

	uint64_t mz_block_type;	/* ZBT_MICRO */

	uint64_t mz_salt;

	uint64_t mz_pad[6];

	mzap_ent_phys_t mz_chunk[1];

	/* actually variable size depending on block size */

} mzap_phys_t;

typedef struct mzap_ent {

	avl_node_t mze_node;

	int mze_chunkid;

	uint64_t mze_hash;

	mzap_ent_phys_t mze_phys;

} mzap_ent_t;

/*

 * The (fat) zap is stored in one object. It is an array of

 * 1<<FZAP_BLOCK_SHIFT byte blocks. The layout looks like one of:

 *

 * ptrtbl fits in first block:

 * 	[zap_phys_t zap_ptrtbl_shift < 6] [zap_leaf_t] ...

 *

 * ptrtbl too big for first block:

 * 	[zap_phys_t zap_ptrtbl_shift >= 6] [zap_leaf_t] [ptrtbl] ...

 *

 */

struct dmu_buf;

struct zap_leaf;

#define	ZBT_LEAF		((1ULL << 63) + 0)

#define	ZBT_HEADER		((1ULL << 63) + 1)

#define	ZBT_MICRO		((1ULL << 63) + 3)

/* any other values are ptrtbl blocks */

/*

 * the embedded pointer table takes up half a block:

 * block size / entry size (2^3) / 2

 */

#define	ZAP_EMBEDDED_PTRTBL_SHIFT(zap) (FZAP_BLOCK_SHIFT(zap) - 3 - 1)

/*

 * The embedded pointer table starts half-way through the block.  Since

 * the pointer table itself is half the block, it starts at (64-bit)

 * word number (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)).

 */

#define	ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) \

	((uint64_t *)(zap)->zap_f.zap_phys) \

	[(idx) + (1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap))]

/*

 * TAKE NOTE:

 * If zap_phys_t is modified, zap_byteswap() must be modified.

 */

typedef struct zap_phys {

	uint64_t zap_block_type;	/* ZBT_HEADER */

	uint64_t zap_magic;		/* ZAP_MAGIC */

	struct zap_table_phys {

		uint64_t zt_blk;	/* starting block number */

		uint64_t zt_numblks;	/* number of blocks */

		uint64_t zt_shift;	/* bits to index it */

		uint64_t zt_nextblk;	/* next (larger) copy start block */

		uint64_t zt_blks_copied; /* number source blocks copied */

	} zap_ptrtbl;

	uint64_t zap_freeblk;		/* the next free block */

	uint64_t zap_num_leafs;		/* number of leafs */

	uint64_t zap_num_entries;	/* number of entries */

	uint64_t zap_salt;		/* salt to stir into hash function */

	/*

	 * This structure is followed by padding, and then the embedded

	 * pointer table.  The embedded pointer table takes up second

	 * half of the block.  It is accessed using the

	 * ZAP_EMBEDDED_PTRTBL_ENT() macro.

	 */

} zap_phys_t;

typedef struct zap_table_phys zap_table_phys_t;

typedef struct zap {

	objset_t *zap_objset;

	uint64_t zap_object;

	struct dmu_buf *zap_dbuf;

	krwlock_t zap_rwlock;

	int zap_ismicro;

	uint64_t zap_salt;

	union {

		struct {

			zap_phys_t *zap_phys;

			/*

			 * zap_num_entries_mtx protects

			 * zap_num_entries

			 */

			kmutex_t zap_num_entries_mtx;

			int zap_block_shift;

		} zap_fat;

		struct {

			mzap_phys_t *zap_phys;

			int16_t zap_num_entries;

			int16_t zap_num_chunks;

			int16_t zap_alloc_next;

			avl_tree_t zap_avl;

		} zap_micro;

	} zap_u;

} zap_t;

#define	zap_f	zap_u.zap_fat

#define	zap_m	zap_u.zap_micro

uint64_t zap_hash(zap_t *zap, const char *name);

int zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx,

    krw_t lti, int fatreader, zap_t **zapp);

void zap_unlockdir(zap_t *zap);

#define	ZAP_HASH_IDX(hash, n) (((n) == 0) ? 0 : ((hash) >> (64 - (n))))

void fzap_byteswap(void *buf, size_t size);

int fzap_count(zap_t *zap, uint64_t *count);

int fzap_lookup(zap_t *zap, const char *name,

    uint64_t integer_size, uint64_t num_integers, void *buf);

int fzap_add(zap_t *zap, const char *name,

    uint64_t integer_size, uint64_t num_integers,

    const void *val, dmu_tx_t *tx);

int fzap_update(zap_t *zap, const char *name,

    int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx);

int fzap_length(zap_t *zap, const char *name,

    uint64_t *integer_size, uint64_t *num_integers);

int fzap_remove(zap_t *zap, const char *name, dmu_tx_t *tx);

int fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za);

void fzap_get_stats(zap_t *zap, zap_stats_t *zs);

void zap_put_leaf(struct zap_leaf *l);

int fzap_add_cd(zap_t *zap, const char *name,

    uint64_t integer_size, uint64_t num_integers,

    const void *val, uint32_t cd, dmu_tx_t *tx);

void fzap_upgrade(zap_t *zap, dmu_tx_t *tx);

#ifdef	__cplusplus

}

#endif

#endif /* _SYS_ZAP_IMPL_H */