LXR linux/lib/zlib_dfltcc/dfltcc.h

   1// SPDX-License-Identifier: Zlib
   2#ifndef DFLTCC_H
   3#define DFLTCC_H
   4
   5#include "../zlib_deflate/defutil.h"
   6#include <asm/facility.h>
   7#include <asm/setup.h>
   8
   9/*
  10 * Tuning parameters.
  11 */
  12#define DFLTCC_LEVEL_MASK 0x2 /* DFLTCC compression for level 1 only */
  13#define DFLTCC_LEVEL_MASK_DEBUG 0x3fe /* DFLTCC compression for all levels */
  14#define DFLTCC_BLOCK_SIZE 1048576
  15#define DFLTCC_FIRST_FHT_BLOCK_SIZE 4096
  16#define DFLTCC_DHT_MIN_SAMPLE_SIZE 4096
  17#define DFLTCC_RIBM 0
  18
  19#define DFLTCC_FACILITY 151
  20
  21/*
  22 * Parameter Block for Query Available Functions.
  23 */
  24struct dfltcc_qaf_param {
  25    char fns[16];
  26    char reserved1[8];
  27    char fmts[2];
  28    char reserved2[6];
  29};
  30
  31static_assert(sizeof(struct dfltcc_qaf_param) == 32);
  32
  33#define DFLTCC_FMT0 0
  34
  35/*
  36 * Parameter Block for Generate Dynamic-Huffman Table, Compress and Expand.
  37 */
  38struct dfltcc_param_v0 {
  39    uint16_t pbvn;                     /* Parameter-Block-Version Number */
  40    uint8_t mvn;                       /* Model-Version Number */
  41    uint8_t ribm;                      /* Reserved for IBM use */
  42    unsigned reserved32 : 31;
  43    unsigned cf : 1;                   /* Continuation Flag */
  44    uint8_t reserved64[8];
  45    unsigned nt : 1;                   /* New Task */
  46    unsigned reserved129 : 1;
  47    unsigned cvt : 1;                  /* Check Value Type */
  48    unsigned reserved131 : 1;
  49    unsigned htt : 1;                  /* Huffman-Table Type */
  50    unsigned bcf : 1;                  /* Block-Continuation Flag */
  51    unsigned bcc : 1;                  /* Block Closing Control */
  52    unsigned bhf : 1;                  /* Block Header Final */
  53    unsigned reserved136 : 1;
  54    unsigned reserved137 : 1;
  55    unsigned dhtgc : 1;                /* DHT Generation Control */
  56    unsigned reserved139 : 5;
  57    unsigned reserved144 : 5;
  58    unsigned sbb : 3;                  /* Sub-Byte Boundary */
  59    uint8_t oesc;                      /* Operation-Ending-Supplemental Code */
  60    unsigned reserved160 : 12;
  61    unsigned ifs : 4;                  /* Incomplete-Function Status */
  62    uint16_t ifl;                      /* Incomplete-Function Length */
  63    uint8_t reserved192[8];
  64    uint8_t reserved256[8];
  65    uint8_t reserved320[4];
  66    uint16_t hl;                       /* History Length */
  67    unsigned reserved368 : 1;
  68    uint16_t ho : 15;                  /* History Offset */
  69    uint32_t cv;                       /* Check Value */
  70    unsigned eobs : 15;                /* End-of-block Symbol */
  71    unsigned reserved431: 1;
  72    uint8_t eobl : 4;                  /* End-of-block Length */
  73    unsigned reserved436 : 12;
  74    unsigned reserved448 : 4;
  75    uint16_t cdhtl : 12;               /* Compressed-Dynamic-Huffman Table
  76                                          Length */
  77    uint8_t reserved464[6];
  78    uint8_t cdht[288];
  79    uint8_t reserved[32];
  80    uint8_t csb[1152];
  81};
  82
  83static_assert(sizeof(struct dfltcc_param_v0) == 1536);
  84
  85#define CVT_CRC32 0
  86#define CVT_ADLER32 1
  87#define HTT_FIXED 0
  88#define HTT_DYNAMIC 1
  89
  90/*
  91 *  Extension of inflate_state and deflate_state for DFLTCC.
  92 */
  93struct dfltcc_state {
  94    struct dfltcc_param_v0 param;      /* Parameter block */
  95    struct dfltcc_qaf_param af;        /* Available functions */
  96    uLong level_mask;                  /* Levels on which to use DFLTCC */
  97    uLong block_size;                  /* New block each X bytes */
  98    uLong block_threshold;             /* New block after total_in > X */
  99    uLong dht_threshold;               /* New block only if avail_in >= X */
 100    char msg[64];                      /* Buffer for strm->msg */
 101};
 102
 103/* Resides right after inflate_state or deflate_state */
 104#define GET_DFLTCC_STATE(state) ((struct dfltcc_state *)((state) + 1))
 105
 106/* External functions */
 107int dfltcc_can_deflate(z_streamp strm);
 108int dfltcc_deflate(z_streamp strm,
 109                   int flush,
 110                   block_state *result);
 111void dfltcc_reset(z_streamp strm, uInt size);
 112int dfltcc_can_inflate(z_streamp strm);
 113typedef enum {
 114    DFLTCC_INFLATE_CONTINUE,
 115    DFLTCC_INFLATE_BREAK,
 116    DFLTCC_INFLATE_SOFTWARE,
 117} dfltcc_inflate_action;
 118dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
 119                                     int flush, int *ret);
 120static inline int is_dfltcc_enabled(void)
 121{
 122return (zlib_dfltcc_support != ZLIB_DFLTCC_DISABLED &&
 123        test_facility(DFLTCC_FACILITY));
 124}
 125
 126#define DEFLATE_RESET_HOOK(strm) \
 127    dfltcc_reset((strm), sizeof(deflate_state))
 128
 129#define DEFLATE_HOOK dfltcc_deflate
 130
 131#define DEFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_deflate((strm)))
 132
 133#define DEFLATE_DFLTCC_ENABLED() is_dfltcc_enabled()
 134
 135#define INFLATE_RESET_HOOK(strm) \
 136    dfltcc_reset((strm), sizeof(struct inflate_state))
 137
 138#define INFLATE_TYPEDO_HOOK(strm, flush) \
 139    if (dfltcc_can_inflate((strm))) { \
 140        dfltcc_inflate_action action; \
 141\
 142        RESTORE(); \
 143        action = dfltcc_inflate((strm), (flush), &ret); \
 144        LOAD(); \
 145        if (action == DFLTCC_INFLATE_CONTINUE) \
 146            break; \
 147        else if (action == DFLTCC_INFLATE_BREAK) \
 148            goto inf_leave; \
 149    }
 150
 151#define INFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_inflate((strm)))
 152
 153#define INFLATE_NEED_UPDATEWINDOW(strm) (!dfltcc_can_inflate((strm)))
 154
 155#endif /* DFLTCC_H */
 156