1 #include <stddef.h>
2 #include <stdint.h>
3 #include <stdio.h>
4 #include <string.h>
5 
6 #ifdef HAVE_SYS_SDT_H
7 #include <sys/sdt.h>
8 #endif
9 
10 /*
11    Tuning parameters.
12  */
13 #ifndef DFLTCC_LEVEL_MASK
14 #define DFLTCC_LEVEL_MASK 0x2
15 #endif
16 #ifndef DFLTCC_BLOCK_SIZE
17 #define DFLTCC_BLOCK_SIZE 1048576
18 #endif
19 #ifndef DFLTCC_FIRST_FHT_BLOCK_SIZE
20 #define DFLTCC_FIRST_FHT_BLOCK_SIZE 4096
21 #endif
22 #ifndef DFLTCC_DHT_MIN_SAMPLE_SIZE
23 #define DFLTCC_DHT_MIN_SAMPLE_SIZE 4096
24 #endif
25 #ifndef DFLTCC_RIBM
26 #define DFLTCC_RIBM 0
27 #endif
28 
29 /*
30    C wrapper for the DEFLATE CONVERSION CALL instruction.
31  */
32 typedef enum {
33     DFLTCC_CC_OK = 0,
34     DFLTCC_CC_OP1_TOO_SHORT = 1,
35     DFLTCC_CC_OP2_TOO_SHORT = 2,
36     DFLTCC_CC_OP2_CORRUPT = 2,
37     DFLTCC_CC_AGAIN = 3,
38 } dfltcc_cc;
39 
40 #define DFLTCC_QAF 0
41 #define DFLTCC_GDHT 1
42 #define DFLTCC_CMPR 2
43 #define DFLTCC_XPND 4
44 #define HBT_CIRCULAR (1 << 7)
45 #define HB_BITS 15
46 #define HB_SIZE (1 << HB_BITS)
47 #define DFLTCC_FACILITY 151
48 
dfltcc(int fn,void * param,unsigned char ** op1,size_t * len1,z_const unsigned char ** op2,size_t * len2,void * hist)49 static inline dfltcc_cc dfltcc(int fn, void *param,
50                                unsigned char **op1, size_t *len1, z_const unsigned char **op2, size_t *len2, void *hist) {
51     unsigned char *t2 = op1 ? *op1 : NULL;
52     size_t t3 = len1 ? *len1 : 0;
53     z_const unsigned char *t4 = op2 ? *op2 : NULL;
54     size_t t5 = len2 ? *len2 : 0;
55     Z_REGISTER int r0 __asm__("r0") = fn;
56     Z_REGISTER void *r1 __asm__("r1") = param;
57     Z_REGISTER unsigned char *r2 __asm__("r2") = t2;
58     Z_REGISTER size_t r3 __asm__("r3") = t3;
59     Z_REGISTER z_const unsigned char *r4 __asm__("r4") = t4;
60     Z_REGISTER size_t r5 __asm__("r5") = t5;
61     int cc;
62 
63     __asm__ volatile(
64 #ifdef HAVE_SYS_SDT_H
65                      STAP_PROBE_ASM(zlib, dfltcc_entry, STAP_PROBE_ASM_TEMPLATE(5))
66 #endif
67                      ".insn rrf,0xb9390000,%[r2],%[r4],%[hist],0\n"
68 #ifdef HAVE_SYS_SDT_H
69                      STAP_PROBE_ASM(zlib, dfltcc_exit, STAP_PROBE_ASM_TEMPLATE(5))
70 #endif
71                      "ipm %[cc]\n"
72                      : [r2] "+r" (r2)
73                      , [r3] "+r" (r3)
74                      , [r4] "+r" (r4)
75                      , [r5] "+r" (r5)
76                      , [cc] "=r" (cc)
77                      : [r0] "r" (r0)
78                      , [r1] "r" (r1)
79                      , [hist] "r" (hist)
80 #ifdef HAVE_SYS_SDT_H
81                      , STAP_PROBE_ASM_OPERANDS(5, r2, r3, r4, r5, hist)
82 #endif
83                      : "cc", "memory");
84     t2 = r2; t3 = r3; t4 = r4; t5 = r5;
85 
86     if (op1)
87         *op1 = t2;
88     if (len1)
89         *len1 = t3;
90     if (op2)
91         *op2 = t4;
92     if (len2)
93         *len2 = t5;
94     return (cc >> 28) & 3;
95 }
96 
97 /*
98    Parameter Block for Query Available Functions.
99  */
100 #define static_assert(c, msg) __attribute__((unused)) static char static_assert_failed_ ## msg[c ? 1 : -1]
101 
102 struct dfltcc_qaf_param {
103     char fns[16];
104     char reserved1[8];
105     char fmts[2];
106     char reserved2[6];
107 };
108 
109 static_assert(sizeof(struct dfltcc_qaf_param) == 32, sizeof_struct_dfltcc_qaf_param_is_32);
110 
is_bit_set(const char * bits,int n)111 static inline int is_bit_set(const char *bits, int n) {
112     return bits[n / 8] & (1 << (7 - (n % 8)));
113 }
114 
clear_bit(char * bits,int n)115 static inline void clear_bit(char *bits, int n) {
116     bits[n / 8] &= ~(1 << (7 - (n % 8)));
117 }
118 
is_dfltcc_enabled(void)119 static inline int is_dfltcc_enabled(void) {
120     uint64_t facilities[(DFLTCC_FACILITY / 64) + 1];
121     Z_REGISTER uint8_t r0 __asm__("r0");
122 
123     memset(facilities, 0, sizeof(facilities));
124     r0 = sizeof(facilities) / sizeof(facilities[0]) - 1;
125     /* STFLE is supported since z9-109 and only in z/Architecture mode. When
126      * compiling with -m31, gcc defaults to ESA mode, however, since the kernel
127      * is 64-bit, it's always z/Architecture mode at runtime.
128      */
129     __asm__ volatile(
130 #ifndef __clang__
131                      ".machinemode push\n"
132                      ".machinemode zarch\n"
133 #endif
134                      "stfle %[facilities]\n"
135 #ifndef __clang__
136                      ".machinemode pop\n"
137 #endif
138                      : [facilities] "=Q" (facilities), [r0] "+r" (r0) :: "cc");
139     return is_bit_set((const char *)facilities, DFLTCC_FACILITY);
140 }
141 
142 #define DFLTCC_FMT0 0
143 
144 /*
145    Parameter Block for Generate Dynamic-Huffman Table, Compress and Expand.
146  */
147 #define CVT_CRC32 0
148 #define CVT_ADLER32 1
149 #define HTT_FIXED 0
150 #define HTT_DYNAMIC 1
151 
152 struct dfltcc_param_v0 {
153     uint16_t pbvn;                     /* Parameter-Block-Version Number */
154     uint8_t mvn;                       /* Model-Version Number */
155     uint8_t ribm;                      /* Reserved for IBM use */
156     uint32_t reserved32 : 31;
157     uint32_t cf : 1;                   /* Continuation Flag */
158     uint8_t reserved64[8];
159     uint32_t nt : 1;                   /* New Task */
160     uint32_t reserved129 : 1;
161     uint32_t cvt : 1;                  /* Check Value Type */
162     uint32_t reserved131 : 1;
163     uint32_t htt : 1;                  /* Huffman-Table Type */
164     uint32_t bcf : 1;                  /* Block-Continuation Flag */
165     uint32_t bcc : 1;                  /* Block Closing Control */
166     uint32_t bhf : 1;                  /* Block Header Final */
167     uint32_t reserved136 : 1;
168     uint32_t reserved137 : 1;
169     uint32_t dhtgc : 1;                /* DHT Generation Control */
170     uint32_t reserved139 : 5;
171     uint32_t reserved144 : 5;
172     uint32_t sbb : 3;                  /* Sub-Byte Boundary */
173     uint8_t oesc;                      /* Operation-Ending-Supplemental Code */
174     uint32_t reserved160 : 12;
175     uint32_t ifs : 4;                  /* Incomplete-Function Status */
176     uint16_t ifl;                      /* Incomplete-Function Length */
177     uint8_t reserved192[8];
178     uint8_t reserved256[8];
179     uint8_t reserved320[4];
180     uint16_t hl;                       /* History Length */
181     uint32_t reserved368 : 1;
182     uint16_t ho : 15;                  /* History Offset */
183     uint32_t cv;                       /* Check Value */
184     uint32_t eobs : 15;                /* End-of-block Symbol */
185     uint32_t reserved431: 1;
186     uint8_t eobl : 4;                  /* End-of-block Length */
187     uint32_t reserved436 : 12;
188     uint32_t reserved448 : 4;
189     uint16_t cdhtl : 12;               /* Compressed-Dynamic-Huffman Table
190                                           Length */
191     uint8_t reserved464[6];
192     uint8_t cdht[288];
193     uint8_t reserved[32];
194     uint8_t csb[1152];
195 };
196 
197 static_assert(sizeof(struct dfltcc_param_v0) == 1536, sizeof_struct_dfltcc_param_v0_is_1536);
198 
oesc_msg(char * buf,int oesc)199 static inline z_const char *oesc_msg(char *buf, int oesc) {
200     if (oesc == 0x00)
201         return NULL; /* Successful completion */
202     else {
203         sprintf(buf, "Operation-Ending-Supplemental Code is 0x%.2X", oesc);
204         return buf;
205     }
206 }
207 
208 /*
209    Extension of inflate_state and deflate_state. Must be doubleword-aligned.
210 */
211 struct dfltcc_state {
212     struct dfltcc_param_v0 param;      /* Parameter block. */
213     struct dfltcc_qaf_param af;        /* Available functions. */
214     char msg[64];                      /* Buffer for strm->msg */
215 };
216 
217 #define ALIGN_UP(p, size) (__typeof__(p))(((uintptr_t)(p) + ((size) - 1)) & ~((size) - 1))
218 
219 #define GET_DFLTCC_STATE(state) ((struct dfltcc_state *)((char *)(state) + ALIGN_UP(sizeof(*state), 8)))
220 
dfltcc_alloc_state(PREFIX3 (streamp)strm,uInt size,uInt extension_size)221 static inline void *dfltcc_alloc_state(PREFIX3(streamp) strm, uInt size, uInt extension_size) {
222     return ZALLOC(strm, 1, ALIGN_UP(size, 8) + extension_size);
223 }
224 
dfltcc_reset_state(struct dfltcc_state * dfltcc_state)225 static inline void dfltcc_reset_state(struct dfltcc_state *dfltcc_state) {
226     /* Initialize available functions */
227     if (is_dfltcc_enabled()) {
228         dfltcc(DFLTCC_QAF, &dfltcc_state->param, NULL, NULL, NULL, NULL, NULL);
229         memmove(&dfltcc_state->af, &dfltcc_state->param, sizeof(dfltcc_state->af));
230     } else
231         memset(&dfltcc_state->af, 0, sizeof(dfltcc_state->af));
232 
233     /* Initialize parameter block */
234     memset(&dfltcc_state->param, 0, sizeof(dfltcc_state->param));
235     dfltcc_state->param.nt = 1;
236     dfltcc_state->param.ribm = DFLTCC_RIBM;
237 }
238 
dfltcc_copy_state(void * dst,const void * src,uInt size,uInt extension_size)239 static inline void dfltcc_copy_state(void *dst, const void *src, uInt size, uInt extension_size) {
240     memcpy(dst, src, ALIGN_UP(size, 8) + extension_size);
241 }
242