/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 2013, 2015 by Delphix. All rights reserved.
 * Copyright (c) 2014 Integros [integros.com]
 */

#ifndef _SYS_SPA_H
#define _SYS_SPA_H

/*
 * General-purpose 32-bit and 64-bit bitfield encodings.
 */
#define BF32_DECODE(x, low, len)        P2PHASE((x) >> (low), 1U << (len))
#define BF64_DECODE(x, low, len)        P2PHASE((x) >> (low), 1ULL << (len))
#define BF32_ENCODE(x, low, len)        (P2PHASE((x), 1U << (len)) << (low))
#define BF64_ENCODE(x, low, len)        (P2PHASE((x), 1ULL << (len)) << (low))

#define BF32_GET(x, low, len)           BF32_DECODE(x, low, len)
#define BF64_GET(x, low, len)           BF64_DECODE(x, low, len)

#define BF32_SET(x, low, len, val)      \
        ((x) ^= BF32_ENCODE((x >> low) ^ (val), low, len))
#define BF64_SET(x, low, len, val)      \
        ((x) ^= BF64_ENCODE((x >> low) ^ (val), low, len))

#define BF32_GET_SB(x, low, len, shift, bias)   \
        ((BF32_GET(x, low, len) + (bias)) << (shift))
#define BF64_GET_SB(x, low, len, shift, bias)   \
        ((BF64_GET(x, low, len) + (bias)) << (shift))

#define BF32_SET_SB(x, low, len, shift, bias, val)      \
        BF32_SET(x, low, len, ((val) >> (shift)) - (bias))
#define BF64_SET_SB(x, low, len, shift, bias, val)      \
        BF64_SET(x, low, len, ((val) >> (shift)) - (bias))

/*
 * Note: GRUB can't actually read blocks larger than 128KB, due to lack
 * of memory.  Therefore its SPA_MAXBLOCKSIZE is still 128KB.
 */
#define SPA_MINBLOCKSHIFT       9
#define SPA_MAXBLOCKSHIFT       17
#define SPA_MINBLOCKSIZE        (1ULL << SPA_MINBLOCKSHIFT)
#define SPA_MAXBLOCKSIZE        (1ULL << SPA_MAXBLOCKSHIFT)

/*
 * Size of block to hold the configuration data (a packed nvlist)
 */
#define SPA_CONFIG_BLOCKSIZE    (1ULL << 14)

/*
 * The DVA size encodings for LSIZE and PSIZE support blocks up to 32MB.
 * The ASIZE encoding should be at least 64 times larger (6 more bits)
 * to support up to 4-way RAID-Z mirror mode with worst-case gang block
 * overhead, three DVAs per bp, plus one more bit in case we do anything
 * else that expands the ASIZE.
 */
#define SPA_LSIZEBITS           16      /* LSIZE up to 32M (2^16 * 512) */
#define SPA_PSIZEBITS           16      /* PSIZE up to 32M (2^16 * 512) */
#define SPA_ASIZEBITS           24      /* ASIZE up to 64 times larger  */

#define SPA_COMPRESSBITS        7

/*
 * All SPA data is represented by 128-bit data virtual addresses (DVAs).
 * The members of the dva_t should be considered opaque outside the SPA.
 */
typedef struct dva {
        uint64_t        dva_word[2];
} dva_t;

/*
 * Each block has a 256-bit checksum -- strong enough for cryptographic hashes.
 */
typedef struct zio_cksum {
        uint64_t        zc_word[4];
} zio_cksum_t;

/*
 * Each block is described by its DVAs, time of birth, checksum, etc.
 * The word-by-word, bit-by-bit layout of the blkptr is as follows:
 *
 *      64      56      48      40      32      24      16      8       0
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 0    |               vdev1           | GRID  |         ASIZE         |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 1    |G|                      offset1                                |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 2    |               vdev2           | GRID  |         ASIZE         |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 3    |G|                      offset2                                |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 4    |               vdev3           | GRID  |         ASIZE         |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 5    |G|                      offset3                                |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 6    |BDX|lvl| type  | cksum |E| comp|    PSIZE      |     LSIZE     |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 7    |                       padding                                 |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 8    |                       padding                                 |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * 9    |                       physical birth txg                      |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * a    |                       logical birth txg                       |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * b    |                       fill count                              |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * c    |                       checksum[0]                             |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * d    |                       checksum[1]                             |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * e    |                       checksum[2]                             |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 * f    |                       checksum[3]                             |
 *      +-------+-------+-------+-------+-------+-------+-------+-------+
 *
 * Legend:
 *
 * vdev         virtual device ID
 * offset       offset into virtual device
 * LSIZE        logical size
 * PSIZE        physical size (after compression)
 * ASIZE        allocated size (including RAID-Z parity and gang block headers)
 * GRID         RAID-Z layout information (reserved for future use)
 * cksum        checksum function
 * comp         compression function
 * G            gang block indicator
 * B            byteorder (endianness)
 * D            dedup
 * X            encryption (on version 30, which is not supported)
 * E            blkptr_t contains embedded data
 * lvl          level of indirection
 * type         DMU object type
 * phys birth   txg of block allocation; zero if same as logical birth txg
 * log. birth   transaction group in which the block was logically born
 * fill count   number of non-zero blocks under this bp
 * checksum[4]  256-bit checksum of the data this bp describes
 */
#define SPA_BLKPTRSHIFT 7               /* blkptr_t is 128 bytes        */
#define SPA_DVAS_PER_BP 3               /* Number of DVAs in a bp       */

typedef struct blkptr {
        dva_t           blk_dva[SPA_DVAS_PER_BP]; /* Data Virtual Addresses */
        uint64_t        blk_prop;       /* size, compression, type, etc     */
        uint64_t        blk_pad[2];     /* Extra space for the future       */
        uint64_t        blk_phys_birth; /* txg when block was allocated     */
        uint64_t        blk_birth;      /* transaction group at birth       */
        uint64_t        blk_fill;       /* fill count                       */
        zio_cksum_t     blk_cksum;      /* 256-bit checksum                 */
} blkptr_t;

/*
 * Macros to get and set fields in a bp or DVA.
 */
#define DVA_GET_ASIZE(dva)      \
        BF64_GET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, SPA_MINBLOCKSHIFT, 0)
#define DVA_SET_ASIZE(dva, x)   \
        BF64_SET_SB((dva)->dva_word[0], 0, SPA_ASIZEBITS, \
        SPA_MINBLOCKSHIFT, 0, x)

#define DVA_GET_GRID(dva)       BF64_GET((dva)->dva_word[0], 24, 8)
#define DVA_SET_GRID(dva, x)    BF64_SET((dva)->dva_word[0], 24, 8, x)

#define DVA_GET_VDEV(dva)       BF64_GET((dva)->dva_word[0], 32, 32)
#define DVA_SET_VDEV(dva, x)    BF64_SET((dva)->dva_word[0], 32, 32, x)

#define DVA_GET_OFFSET(dva)     \
        BF64_GET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0)
#define DVA_SET_OFFSET(dva, x)  \
        BF64_SET_SB((dva)->dva_word[1], 0, 63, SPA_MINBLOCKSHIFT, 0, x)

#define DVA_GET_GANG(dva)       BF64_GET((dva)->dva_word[1], 63, 1)
#define DVA_SET_GANG(dva, x)    BF64_SET((dva)->dva_word[1], 63, 1, x)

#define BP_GET_LSIZE(bp)        \
        BF64_GET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1)
#define BP_SET_LSIZE(bp, x)     \
        BF64_SET_SB((bp)->blk_prop, 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)

#define BP_GET_PSIZE(bp)        \
        BF64_GET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1)
#define BP_SET_PSIZE(bp, x)     \
        BF64_SET_SB((bp)->blk_prop, 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x)

#define BP_GET_COMPRESS(bp)             \
        BF64_GET((bp)->blk_prop, 32, SPA_COMPRESSBITS)
#define BP_SET_COMPRESS(bp, x)          \
        BF64_SET((bp)->blk_prop, 32, SPA_COMPRESSBITS, x)

#define BP_GET_CHECKSUM(bp)             BF64_GET((bp)->blk_prop, 40, 8)
#define BP_SET_CHECKSUM(bp, x)          BF64_SET((bp)->blk_prop, 40, 8, x)

#define BP_GET_TYPE(bp)                 BF64_GET((bp)->blk_prop, 48, 8)
#define BP_SET_TYPE(bp, x)              BF64_SET((bp)->blk_prop, 48, 8, x)

#define BP_GET_LEVEL(bp)                BF64_GET((bp)->blk_prop, 56, 5)
#define BP_SET_LEVEL(bp, x)             BF64_SET((bp)->blk_prop, 56, 5, x)

#define BP_IS_EMBEDDED(bp)              BF64_GET((bp)->blk_prop, 39, 1)

#define BP_GET_DEDUP(bp)                BF64_GET((bp)->blk_prop, 62, 1)
#define BP_SET_DEDUP(bp, x)             BF64_SET((bp)->blk_prop, 62, 1, x)

#define BP_GET_BYTEORDER(bp)            BF64_GET((bp)->blk_prop, 63, 1)
#define BP_SET_BYTEORDER(bp, x)         BF64_SET((bp)->blk_prop, 63, 1, x)

#define BP_PHYSICAL_BIRTH(bp)           \
        ((bp)->blk_phys_birth ? (bp)->blk_phys_birth : (bp)->blk_birth)

#define BP_SET_BIRTH(bp, logical, physical)     \
{                                               \
        (bp)->blk_birth = (logical);            \
        (bp)->blk_phys_birth = ((logical) == (physical) ? 0 : (physical)); \
}

#define BP_GET_ASIZE(bp)        \
        (DVA_GET_ASIZE(&(bp)->blk_dva[0]) + DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
                DVA_GET_ASIZE(&(bp)->blk_dva[2]))

#define BP_GET_UCSIZE(bp) \
        ((BP_GET_LEVEL(bp) > 0 || dmu_ot[BP_GET_TYPE(bp)].ot_metadata) ? \
        BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp));

#define BP_GET_NDVAS(bp)        \
        (!!DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
        !!DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
        !!DVA_GET_ASIZE(&(bp)->blk_dva[2]))

#define DVA_EQUAL(dva1, dva2)   \
        ((dva1)->dva_word[1] == (dva2)->dva_word[1] && \
        (dva1)->dva_word[0] == (dva2)->dva_word[0])

#define BP_EQUAL(bp1, bp2)      \
        (BP_PHYSICAL_BIRTH(bp1) == BP_PHYSICAL_BIRTH(bp2) &&    \
        DVA_EQUAL(&(bp1)->blk_dva[0], &(bp2)->blk_dva[0]) &&    \
        DVA_EQUAL(&(bp1)->blk_dva[1], &(bp2)->blk_dva[1]) &&    \
        DVA_EQUAL(&(bp1)->blk_dva[2], &(bp2)->blk_dva[2]))

#define ZIO_CHECKSUM_EQUAL(zc1, zc2) \
        (0 == (((zc1).zc_word[0] - (zc2).zc_word[0]) | \
        ((zc1).zc_word[1] - (zc2).zc_word[1]) | \
        ((zc1).zc_word[2] - (zc2).zc_word[2]) | \
        ((zc1).zc_word[3] - (zc2).zc_word[3])))

#define DVA_IS_VALID(dva)       (DVA_GET_ASIZE(dva) != 0)

#define ZIO_SET_CHECKSUM(zcp, w0, w1, w2, w3)   \
{                                               \
        (zcp)->zc_word[0] = w0;                 \
        (zcp)->zc_word[1] = w1;                 \
        (zcp)->zc_word[2] = w2;                 \
        (zcp)->zc_word[3] = w3;                 \
}

#define BP_IDENTITY(bp)         (&(bp)->blk_dva[0])
#define BP_IS_GANG(bp)          DVA_GET_GANG(BP_IDENTITY(bp))
#define DVA_IS_EMPTY(dva)       ((dva)->dva_word[0] == 0ULL &&  \
                                (dva)->dva_word[1] == 0ULL)
#define BP_IS_HOLE(bp)          DVA_IS_EMPTY(BP_IDENTITY(bp))

/* BP_IS_RAIDZ(bp) assumes no block compression */
#define BP_IS_RAIDZ(bp)         (DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \
                                BP_GET_PSIZE(bp))

#define BP_ZERO(bp)                             \
{                                               \
        (bp)->blk_dva[0].dva_word[0] = 0;       \
        (bp)->blk_dva[0].dva_word[1] = 0;       \
        (bp)->blk_dva[1].dva_word[0] = 0;       \
        (bp)->blk_dva[1].dva_word[1] = 0;       \
        (bp)->blk_dva[2].dva_word[0] = 0;       \
        (bp)->blk_dva[2].dva_word[1] = 0;       \
        (bp)->blk_prop = 0;                     \
        (bp)->blk_pad[0] = 0;                   \
        (bp)->blk_pad[1] = 0;                   \
        (bp)->blk_phys_birth = 0;               \
        (bp)->blk_birth = 0;                    \
        (bp)->blk_fill = 0;                     \
        ZIO_SET_CHECKSUM(&(bp)->blk_cksum, 0, 0, 0, 0); \
}

#define BPE_GET_ETYPE(bp)       BP_GET_CHECKSUM(bp)
#define BPE_GET_LSIZE(bp)       \
        BF64_GET_SB((bp)->blk_prop, 0, 25, 0, 1)
#define BPE_GET_PSIZE(bp)       \
        BF64_GET_SB((bp)->blk_prop, 25, 7, 0, 1)

typedef enum bp_embedded_type {
        BP_EMBEDDED_TYPE_DATA,
        NUM_BP_EMBEDDED_TYPES
} bp_embedded_type_t;

#define BPE_NUM_WORDS 14
#define BPE_PAYLOAD_SIZE (BPE_NUM_WORDS * sizeof (uint64_t))
#define BPE_IS_PAYLOADWORD(bp, wp) \
        ((wp) != &(bp)->blk_prop && (wp) != &(bp)->blk_birth)

#ifdef _BIG_ENDIAN
#define ZFS_HOST_BYTEORDER      (0ULL)
#else
#define ZFS_HOST_BYTEORDER      (1ULL)
#endif

#define BP_SHOULD_BYTESWAP(bp)  (BP_GET_BYTEORDER(bp) != ZFS_HOST_BYTEORDER)

#define BP_SPRINTF_LEN  320

#endif  /* _SYS_SPA_H */