Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
[qemu.git] / thunk.c
1 /*
2 * Generic thunking code to convert data between host and target CPU
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 */
19 #include "qemu/osdep.h"
20
21 #include "qemu.h"
22 #include "exec/user/thunk.h"
23
24 //#define DEBUG
25
26 static unsigned int max_struct_entries;
27 StructEntry *struct_entries;
28
29 static const argtype *thunk_type_next_ptr(const argtype *type_ptr);
30
31 static inline const argtype *thunk_type_next(const argtype *type_ptr)
32 {
33 int type;
34
35 type = *type_ptr++;
36 switch(type) {
37 case TYPE_CHAR:
38 case TYPE_SHORT:
39 case TYPE_INT:
40 case TYPE_LONGLONG:
41 case TYPE_ULONGLONG:
42 case TYPE_LONG:
43 case TYPE_ULONG:
44 case TYPE_PTRVOID:
45 case TYPE_OLDDEVT:
46 return type_ptr;
47 case TYPE_PTR:
48 return thunk_type_next_ptr(type_ptr);
49 case TYPE_ARRAY:
50 return thunk_type_next_ptr(type_ptr + 1);
51 case TYPE_STRUCT:
52 return type_ptr + 1;
53 default:
54 return NULL;
55 }
56 }
57
58 static const argtype *thunk_type_next_ptr(const argtype *type_ptr)
59 {
60 return thunk_type_next(type_ptr);
61 }
62
63 void thunk_register_struct(int id, const char *name, const argtype *types)
64 {
65 const argtype *type_ptr;
66 StructEntry *se;
67 int nb_fields, offset, max_align, align, size, i, j;
68
69 assert(id < max_struct_entries);
70
71 /* first we count the number of fields */
72 type_ptr = types;
73 nb_fields = 0;
74 while (*type_ptr != TYPE_NULL) {
75 type_ptr = thunk_type_next(type_ptr);
76 nb_fields++;
77 }
78 assert(nb_fields > 0);
79 se = struct_entries + id;
80 se->field_types = types;
81 se->nb_fields = nb_fields;
82 se->name = name;
83 #ifdef DEBUG
84 printf("struct %s: id=%d nb_fields=%d\n",
85 se->name, id, se->nb_fields);
86 #endif
87 /* now we can alloc the data */
88
89 for (i = 0; i < ARRAY_SIZE(se->field_offsets); i++) {
90 offset = 0;
91 max_align = 1;
92 se->field_offsets[i] = g_new(int, nb_fields);
93 type_ptr = se->field_types;
94 for(j = 0;j < nb_fields; j++) {
95 size = thunk_type_size(type_ptr, i);
96 align = thunk_type_align(type_ptr, i);
97 offset = (offset + align - 1) & ~(align - 1);
98 se->field_offsets[i][j] = offset;
99 offset += size;
100 if (align > max_align)
101 max_align = align;
102 type_ptr = thunk_type_next(type_ptr);
103 }
104 offset = (offset + max_align - 1) & ~(max_align - 1);
105 se->size[i] = offset;
106 se->align[i] = max_align;
107 #ifdef DEBUG
108 printf("%s: size=%d align=%d\n",
109 i == THUNK_HOST ? "host" : "target", offset, max_align);
110 #endif
111 }
112 }
113
114 void thunk_register_struct_direct(int id, const char *name,
115 const StructEntry *se1)
116 {
117 StructEntry *se;
118
119 assert(id < max_struct_entries);
120 se = struct_entries + id;
121 *se = *se1;
122 se->name = name;
123 }
124
125
126 /* now we can define the main conversion functions */
127 const argtype *thunk_convert(void *dst, const void *src,
128 const argtype *type_ptr, int to_host)
129 {
130 int type;
131
132 type = *type_ptr++;
133 switch(type) {
134 case TYPE_CHAR:
135 *(uint8_t *)dst = *(uint8_t *)src;
136 break;
137 case TYPE_SHORT:
138 *(uint16_t *)dst = tswap16(*(uint16_t *)src);
139 break;
140 case TYPE_INT:
141 *(uint32_t *)dst = tswap32(*(uint32_t *)src);
142 break;
143 case TYPE_LONGLONG:
144 case TYPE_ULONGLONG:
145 *(uint64_t *)dst = tswap64(*(uint64_t *)src);
146 break;
147 #if HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 32
148 case TYPE_LONG:
149 case TYPE_ULONG:
150 case TYPE_PTRVOID:
151 *(uint32_t *)dst = tswap32(*(uint32_t *)src);
152 break;
153 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 32
154 case TYPE_LONG:
155 case TYPE_ULONG:
156 case TYPE_PTRVOID:
157 if (to_host) {
158 if (type == TYPE_LONG) {
159 /* sign extension */
160 *(uint64_t *)dst = (int32_t)tswap32(*(uint32_t *)src);
161 } else {
162 *(uint64_t *)dst = tswap32(*(uint32_t *)src);
163 }
164 } else {
165 *(uint32_t *)dst = tswap32(*(uint64_t *)src & 0xffffffff);
166 }
167 break;
168 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64
169 case TYPE_LONG:
170 case TYPE_ULONG:
171 case TYPE_PTRVOID:
172 *(uint64_t *)dst = tswap64(*(uint64_t *)src);
173 break;
174 #elif HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 64
175 case TYPE_LONG:
176 case TYPE_ULONG:
177 case TYPE_PTRVOID:
178 if (to_host) {
179 *(uint32_t *)dst = tswap64(*(uint64_t *)src);
180 } else {
181 if (type == TYPE_LONG) {
182 /* sign extension */
183 *(uint64_t *)dst = tswap64(*(int32_t *)src);
184 } else {
185 *(uint64_t *)dst = tswap64(*(uint32_t *)src);
186 }
187 }
188 break;
189 #else
190 #warning unsupported conversion
191 #endif
192 case TYPE_OLDDEVT:
193 {
194 uint64_t val = 0;
195 switch (thunk_type_size(type_ptr - 1, !to_host)) {
196 case 2:
197 val = *(uint16_t *)src;
198 break;
199 case 4:
200 val = *(uint32_t *)src;
201 break;
202 case 8:
203 val = *(uint64_t *)src;
204 break;
205 }
206 switch (thunk_type_size(type_ptr - 1, to_host)) {
207 case 2:
208 *(uint16_t *)dst = tswap16(val);
209 break;
210 case 4:
211 *(uint32_t *)dst = tswap32(val);
212 break;
213 case 8:
214 *(uint64_t *)dst = tswap64(val);
215 break;
216 }
217 break;
218 }
219 case TYPE_ARRAY:
220 {
221 int array_length, i, dst_size, src_size;
222 const uint8_t *s;
223 uint8_t *d;
224
225 array_length = *type_ptr++;
226 dst_size = thunk_type_size(type_ptr, to_host);
227 src_size = thunk_type_size(type_ptr, 1 - to_host);
228 d = dst;
229 s = src;
230 for(i = 0;i < array_length; i++) {
231 thunk_convert(d, s, type_ptr, to_host);
232 d += dst_size;
233 s += src_size;
234 }
235 type_ptr = thunk_type_next(type_ptr);
236 }
237 break;
238 case TYPE_STRUCT:
239 {
240 int i;
241 const StructEntry *se;
242 const uint8_t *s;
243 uint8_t *d;
244 const argtype *field_types;
245 const int *dst_offsets, *src_offsets;
246
247 assert(*type_ptr < max_struct_entries);
248 se = struct_entries + *type_ptr++;
249 if (se->convert[0] != NULL) {
250 /* specific conversion is needed */
251 (*se->convert[to_host])(dst, src);
252 } else {
253 /* standard struct conversion */
254 field_types = se->field_types;
255 dst_offsets = se->field_offsets[to_host];
256 src_offsets = se->field_offsets[1 - to_host];
257 d = dst;
258 s = src;
259 for(i = 0;i < se->nb_fields; i++) {
260 field_types = thunk_convert(d + dst_offsets[i],
261 s + src_offsets[i],
262 field_types, to_host);
263 }
264 }
265 }
266 break;
267 default:
268 fprintf(stderr, "Invalid type 0x%x\n", type);
269 break;
270 }
271 return type_ptr;
272 }
273
274 /* from em86 */
275
276 /* Utility function: Table-driven functions to translate bitmasks
277 * between host and target formats
278 */
279 unsigned int target_to_host_bitmask(unsigned int target_mask,
280 const bitmask_transtbl * trans_tbl)
281 {
282 const bitmask_transtbl *btp;
283 unsigned int host_mask = 0;
284
285 for (btp = trans_tbl; btp->target_mask && btp->host_mask; btp++) {
286 if ((target_mask & btp->target_mask) == btp->target_bits) {
287 host_mask |= btp->host_bits;
288 }
289 }
290 return host_mask;
291 }
292
293 unsigned int host_to_target_bitmask(unsigned int host_mask,
294 const bitmask_transtbl * trans_tbl)
295 {
296 const bitmask_transtbl *btp;
297 unsigned int target_mask = 0;
298
299 for (btp = trans_tbl; btp->target_mask && btp->host_mask; btp++) {
300 if ((host_mask & btp->host_mask) == btp->host_bits) {
301 target_mask |= btp->target_bits;
302 }
303 }
304 return target_mask;
305 }
306
307 int thunk_type_size_array(const argtype *type_ptr, int is_host)
308 {
309 return thunk_type_size(type_ptr, is_host);
310 }
311
312 int thunk_type_align_array(const argtype *type_ptr, int is_host)
313 {
314 return thunk_type_align(type_ptr, is_host);
315 }
316
317 void thunk_init(unsigned int max_structs)
318 {
319 max_struct_entries = max_structs;
320 struct_entries = g_new0(StructEntry, max_structs);
321 }