/*
 * 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) 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2013 by Delphix. All rights reserved.
 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
 */

#ifndef _SYS_SA_IMPL_H
#define _SYS_SA_IMPL_H

#include <sys/dmu.h>
#include <sys/refcount.h>
#include <sys/list.h>

/*
 * Array of known attributes and their
 * various characteristics.
 */
typedef struct sa_attr_table {
        sa_attr_type_t  sa_attr;
        uint8_t sa_registered;
        uint16_t sa_length;
        sa_bswap_type_t sa_byteswap;
        char *sa_name;
} sa_attr_table_t;

/*
 * Zap attribute format for attribute registration
 *
 * 64      56      48      40      32      24      16      8       0
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 * |        unused         |      len      | bswap |   attr num    |
 * +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * Zap attribute format for layout information.
 *
 * layout information is stored as an array of attribute numbers
 * The name of the attribute is the layout number (0, 1, 2, ...)
 *
 * 16       0
 * +---- ---+
 * | attr # |
 * +--------+
 * | attr # |
 * +--- ----+
 *  ......
 *
 */

#define ATTR_BSWAP(x)   BF32_GET(x, 16, 8)
#define ATTR_LENGTH(x)  BF32_GET(x, 24, 16)
#define ATTR_NUM(x)     BF32_GET(x, 0, 16)
#define ATTR_ENCODE(x, attr, length, bswap) \
{ \
        BF64_SET(x, 24, 16, length); \
        BF64_SET(x, 16, 8, bswap); \
        BF64_SET(x, 0, 16, attr); \
}

#define TOC_OFF(x)              BF32_GET(x, 0, 23)
#define TOC_ATTR_PRESENT(x)     BF32_GET(x, 31, 1)
#define TOC_LEN_IDX(x)          BF32_GET(x, 24, 4)
#define TOC_ATTR_ENCODE(x, len_idx, offset) \
{ \
        BF32_SET(x, 31, 1, 1); \
        BF32_SET(x, 24, 7, len_idx); \
        BF32_SET(x, 0, 24, offset); \
}

#define SA_LAYOUTS      "LAYOUTS"
#define SA_REGISTRY     "REGISTRY"

/*
 * Each unique layout will have their own table
 * sa_lot (layout_table)
 */
typedef struct sa_lot {
        avl_node_t lot_num_node;
        avl_node_t lot_hash_node;
        uint64_t lot_num;
        uint64_t lot_hash;
        sa_attr_type_t *lot_attrs;      /* array of attr #'s */
        uint32_t lot_var_sizes; /* how many aren't fixed size */
        uint32_t lot_attr_count;        /* total attr count */
        list_t  lot_idx_tab;    /* should be only a couple of entries */
        int     lot_instance;   /* used with lot_hash to identify entry */
} sa_lot_t;

/* index table of offsets */
typedef struct sa_idx_tab {
        list_node_t     sa_next;
        sa_lot_t        *sa_layout;
        uint16_t        *sa_variable_lengths;
        zfs_refcount_t  sa_refcount;
        uint32_t        *sa_idx_tab;    /* array of offsets */
} sa_idx_tab_t;

/*
 * Since the offset/index information into the actual data
 * will usually be identical we can share that information with
 * all handles that have the exact same offsets.
 *
 * You would typically only have a large number of different table of
 * contents if you had a several variable sized attributes.
 *
 * Two AVL trees are used to track the attribute layout numbers.
 * one is keyed by number and will be consulted when a DMU_OT_SA
 * object is first read.  The second tree is keyed by the hash signature
 * of the attributes and will be consulted when an attribute is added
 * to determine if we already have an instance of that layout.  Both
 * of these tree's are interconnected.  The only difference is that
 * when an entry is found in the "hash" tree the list of attributes will
 * need to be compared against the list of attributes you have in hand.
 * The assumption is that typically attributes will just be updated and
 * adding a completely new attribute is a very rare operation.
 */
struct sa_os {
        kmutex_t        sa_lock;
        boolean_t       sa_need_attr_registration;
        boolean_t       sa_force_spill;
        uint64_t        sa_master_obj;
        uint64_t        sa_reg_attr_obj;
        uint64_t        sa_layout_attr_obj;
        int             sa_num_attrs;
        sa_attr_table_t *sa_attr_table;  /* private attr table */
        sa_update_cb_t  *sa_update_cb;
        avl_tree_t      sa_layout_num_tree;  /* keyed by layout number */
        avl_tree_t      sa_layout_hash_tree; /* keyed by layout hash value */
        int             sa_user_table_sz;
        sa_attr_type_t  *sa_user_table; /* user name->attr mapping table */
};

/*
 * header for all bonus and spill buffers.
 *
 * The header has a fixed portion with a variable number
 * of "lengths" depending on the number of variable sized
 * attributes which are determined by the "layout number"
 */

#define SA_MAGIC        0x2F505A  /* ZFS SA */
typedef struct sa_hdr_phys {
        uint32_t sa_magic;
        /* BEGIN CSTYLED */
        /*
         * Encoded with hdrsize and layout number as follows:
         * 16      10       0
         * +--------+-------+
         * | hdrsz  |layout |
         * +--------+-------+
         *
         * Bits 0-10 are the layout number
         * Bits 11-16 are the size of the header.
         * The hdrsize is the number * 8
         *
         * For example.
         * hdrsz of 1 ==> 8 byte header
         *          2 ==> 16 byte header
         *
         */
        /* END CSTYLED */
        uint16_t sa_layout_info;
        uint16_t sa_lengths[1]; /* optional sizes for variable length attrs */
        /* ... Data follows the lengths.  */
} sa_hdr_phys_t;

#define SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
#define SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 6, 3, 0)
#define SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
{ \
        BF32_SET_SB(x, 10, 6, 3, 0, size); \
        BF32_SET(x, 0, 10, num); \
}

typedef enum sa_buf_type {
        SA_BONUS = 1,
        SA_SPILL = 2
} sa_buf_type_t;

typedef enum sa_data_op {
        SA_LOOKUP,
        SA_UPDATE,
        SA_ADD,
        SA_REPLACE,
        SA_REMOVE
} sa_data_op_t;

/*
 * Opaque handle used for most sa functions
 *
 * This needs to be kept as small as possible.
 */

struct sa_handle {
        dmu_buf_user_t  sa_dbu;
        kmutex_t        sa_lock;
        dmu_buf_t       *sa_bonus;
        dmu_buf_t       *sa_spill;
        objset_t        *sa_os;
        void            *sa_userp;
        sa_idx_tab_t    *sa_bonus_tab;   /* idx of bonus */
        sa_idx_tab_t    *sa_spill_tab; /* only present if spill activated */
};

#define SA_GET_DB(hdl, type)    \
        (dmu_buf_impl_t *)((type == SA_BONUS) ? hdl->sa_bonus : hdl->sa_spill)

#define SA_GET_HDR(hdl, type) \
        ((sa_hdr_phys_t *)((dmu_buf_impl_t *)(SA_GET_DB(hdl, \
        type))->db.db_data))

#define SA_IDX_TAB_GET(hdl, type) \
        (type == SA_BONUS ? hdl->sa_bonus_tab : hdl->sa_spill_tab)

#define IS_SA_BONUSTYPE(a)      \
        ((a == DMU_OT_SA) ? B_TRUE : B_FALSE)

#define SA_BONUSTYPE_FROM_DB(db) \
        (dmu_get_bonustype((dmu_buf_t *)db))

#define SA_BLKPTR_SPACE (DN_OLD_MAX_BONUSLEN - sizeof (blkptr_t))

#define SA_LAYOUT_NUM(x, type) \
        ((!IS_SA_BONUSTYPE(type) ? 0 : (((IS_SA_BONUSTYPE(type)) && \
        ((SA_HDR_LAYOUT_NUM(x)) == 0)) ? 1 : SA_HDR_LAYOUT_NUM(x))))


#define SA_REGISTERED_LEN(sa, attr) sa->sa_attr_table[attr].sa_length

#define SA_ATTR_LEN(sa, idx, attr, hdr) ((SA_REGISTERED_LEN(sa, attr) == 0) ?\
        hdr->sa_lengths[TOC_LEN_IDX(idx->sa_idx_tab[attr])] : \
        SA_REGISTERED_LEN(sa, attr))

#define SA_SET_HDR(hdr, num, size) \
        { \
                hdr->sa_magic = SA_MAGIC; \
                SA_HDR_LAYOUT_INFO_ENCODE(hdr->sa_layout_info, num, size); \
        }

#define SA_ATTR_INFO(sa, idx, hdr, attr, bulk, type, hdl) \
        { \
                bulk.sa_size = SA_ATTR_LEN(sa, idx, attr, hdr); \
                bulk.sa_buftype = type; \
                bulk.sa_addr = \
                    (void *)((uintptr_t)TOC_OFF(idx->sa_idx_tab[attr]) + \
                    (uintptr_t)hdr); \
}

#define SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) \
        (SA_HDR_SIZE(hdr) == (sizeof (sa_hdr_phys_t) + \
        (tb->lot_var_sizes > 1 ? P2ROUNDUP((tb->lot_var_sizes - 1) * \
        sizeof (uint16_t), 8) : 0)))

int sa_add_impl(sa_handle_t *, sa_attr_type_t,
    uint32_t, sa_data_locator_t, void *, dmu_tx_t *);

void sa_register_update_callback_locked(objset_t *, sa_update_cb_t *);
int sa_size_locked(sa_handle_t *, sa_attr_type_t, int *);

void sa_default_locator(void **, uint32_t *, uint32_t, boolean_t, void *);
int sa_attr_size(sa_os_t *, sa_idx_tab_t *, sa_attr_type_t,
    uint16_t *, sa_hdr_phys_t *);

#ifdef  __cplusplus
extern "C" {
#endif

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_SA_IMPL_H */