1// SPDX-License-Identifier: Zlib
2#ifndef DFLTCC_UTIL_H
3#define DFLTCC_UTIL_H
4
5#include <linux/zutil.h>
6
7/*
8 * C wrapper for the DEFLATE CONVERSION CALL instruction.
9 */
10typedef enum {
11    DFLTCC_CC_OK = 0,
12    DFLTCC_CC_OP1_TOO_SHORT = 1,
13    DFLTCC_CC_OP2_TOO_SHORT = 2,
14    DFLTCC_CC_OP2_CORRUPT = 2,
15    DFLTCC_CC_AGAIN = 3,
16} dfltcc_cc;
17
18#define DFLTCC_QAF 0
19#define DFLTCC_GDHT 1
20#define DFLTCC_CMPR 2
21#define DFLTCC_XPND 4
22#define HBT_CIRCULAR (1 << 7)
23#define HB_BITS 15
24#define HB_SIZE (1 << HB_BITS)
25
26static inline dfltcc_cc dfltcc(
27    int fn,
28    void *param,
29    Byte **op1,
30    size_t *len1,
31    const Byte **op2,
32    size_t *len2,
33    void *hist
34)
35{
36    Byte *t2 = op1 ? *op1 : NULL;
37    size_t t3 = len1 ? *len1 : 0;
38    const Byte *t4 = op2 ? *op2 : NULL;
39    size_t t5 = len2 ? *len2 : 0;
40    register int r0 __asm__("r0") = fn;
41    register void *r1 __asm__("r1") = param;
42    register Byte *r2 __asm__("r2") = t2;
43    register size_t r3 __asm__("r3") = t3;
44    register const Byte *r4 __asm__("r4") = t4;
45    register size_t r5 __asm__("r5") = t5;
46    int cc;
47
48    __asm__ volatile(
49                     ".insn rrf,0xb9390000,%[r2],%[r4],%[hist],0\n"
50                     "ipm %[cc]\n"
51                     : [r2] "+r" (r2)
52                     , [r3] "+r" (r3)
53                     , [r4] "+r" (r4)
54                     , [r5] "+r" (r5)
55                     , [cc] "=r" (cc)
56                     : [r0] "r" (r0)
57                     , [r1] "r" (r1)
58                     , [hist] "r" (hist)
59                     : "cc", "memory");
60    t2 = r2; t3 = r3; t4 = r4; t5 = r5;
61
62    if (op1)
63        *op1 = t2;
64    if (len1)
65        *len1 = t3;
66    if (op2)
67        *op2 = t4;
68    if (len2)
69        *len2 = t5;
70    return (cc >> 28) & 3;
71}
72
73static inline int is_bit_set(
74    const char *bits,
75    int n
76)
77{
78    return bits[n / 8] & (1 << (7 - (n % 8)));
79}
80
81static inline void turn_bit_off(
82    char *bits,
83    int n
84)
85{
86    bits[n / 8] &= ~(1 << (7 - (n % 8)));
87}
88
89static inline int dfltcc_are_params_ok(
90    int level,
91    uInt window_bits,
92    int strategy,
93    uLong level_mask
94)
95{
96    return (level_mask & (1 << level)) != 0 &&
97        (window_bits == HB_BITS) &&
98        (strategy == Z_DEFAULT_STRATEGY);
99}
100
101char *oesc_msg(char *buf, int oesc);
102
103#endif /* DFLTCC_UTIL_H */
104