/*
 * 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
 * Copyright (c) 2014 Integros [integros.com]
 * Copyright 2017 Nexenta Systems, Inc.
 */

#ifndef _SYS_ZAP_IMPL_H
#define _SYS_ZAP_IMPL_H

#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 0x2F52AB2ABULL

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

#define MZAP_ENT_LEN            64
#define MZAP_NAME_LEN           (MZAP_ENT_LEN - 8 - 4 - 2)
#define MZAP_MAX_BLKSZ          SPA_OLD_MAXBLOCKSIZE

#define ZAP_NEED_CD             (-1U)

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_normflags;
        uint64_t mz_pad[5];
        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;
        uint32_t mze_cd; /* copy from mze_phys->mze_cd */
} mzap_ent_t;

#define MZE_PHYS(zap, mze) \
        (&zap_m_phys(zap)->mz_chunk[(mze)->mze_chunkid])

/*
 * 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_f_phys(zap)) \
        [(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 */
        uint64_t zap_normflags;         /* flags for u8_textprep_str() */
        uint64_t zap_flags;             /* zap_flags_t */
        /*
         * 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 {
        dmu_buf_user_t zap_dbu;
        objset_t *zap_objset;
        uint64_t zap_object;
        struct dmu_buf *zap_dbuf;
        krwlock_t zap_rwlock;
        boolean_t zap_ismicro;
        int zap_normflags;
        uint64_t zap_salt;
        union {
                struct {
                        /*
                         * zap_num_entries_mtx protects
                         * zap_num_entries
                         */
                        kmutex_t zap_num_entries_mtx;
                        int zap_block_shift;
                } zap_fat;
                struct {
                        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;

inline zap_phys_t *
zap_f_phys(zap_t *zap)
{
        return (zap->zap_dbuf->db_data);
}

inline mzap_phys_t *
zap_m_phys(zap_t *zap)
{
        return (zap->zap_dbuf->db_data);
}

typedef struct zap_name {
        zap_t *zn_zap;
        int zn_key_intlen;
        const void *zn_key_orig;
        int zn_key_orig_numints;
        const void *zn_key_norm;
        int zn_key_norm_numints;
        uint64_t zn_hash;
        matchtype_t zn_matchtype;
        int zn_normflags;
        char zn_normbuf[ZAP_MAXNAMELEN];
} zap_name_t;

#define zap_f   zap_u.zap_fat
#define zap_m   zap_u.zap_micro

boolean_t zap_match(zap_name_t *zn, const char *matchname);
int zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx,
    krw_t lti, boolean_t fatreader, boolean_t adding, void *tag, zap_t **zapp);
void zap_unlockdir(zap_t *zap, void *tag);
void zap_evict_sync(void *dbu);
zap_name_t *zap_name_alloc(zap_t *zap, const char *key, matchtype_t mt);
void zap_name_free(zap_name_t *zn);
int zap_hashbits(zap_t *zap);
uint32_t zap_maxcd(zap_t *zap);
uint64_t zap_getflags(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_name_t *zn,
    uint64_t integer_size, uint64_t num_integers, void *buf,
    char *realname, int rn_len, boolean_t *normalization_conflictp);
void fzap_prefetch(zap_name_t *zn);
int fzap_add(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers,
    const void *val, void *tag, dmu_tx_t *tx);
int fzap_update(zap_name_t *zn,
    int integer_size, uint64_t num_integers, const void *val,
    void *tag, dmu_tx_t *tx);
int fzap_length(zap_name_t *zn,
    uint64_t *integer_size, uint64_t *num_integers);
int fzap_remove(zap_name_t *zn, 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_name_t *zn,
    uint64_t integer_size, uint64_t num_integers,
    const void *val, uint32_t cd, void *tag, dmu_tx_t *tx);
void fzap_upgrade(zap_t *zap, dmu_tx_t *tx, zap_flags_t flags);

#ifdef  __cplusplus
}
#endif

#endif /* _SYS_ZAP_IMPL_H */