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  */
  24 struct dfltcc_qaf_param {
  25     char fns[16];
  26     char reserved1[8];
  27     char fmts[2];
  28     char reserved2[6];
  29 };
  30
  31 static_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  */
  38 struct 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
  83 static_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  */
  93 struct 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 */
 107 int dfltcc_can_deflate(z_streamp strm);
 108 int dfltcc_deflate(z_streamp strm,
 109                    int flush,
 110                    block_state *result);
 111 void dfltcc_reset(z_streamp strm, uInt size);
 112 int dfltcc_can_inflate(z_streamp strm);
 113 typedef enum {
 114     DFLTCC_INFLATE_CONTINUE,
 115     DFLTCC_INFLATE_BREAK,
 116     DFLTCC_INFLATE_SOFTWARE,
 117 } dfltcc_inflate_action;
 118 dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
 119                                      int flush, int *ret);
 120 static inline int is_dfltcc_enabled(void)
 121 {
 122 return (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 */