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 */