linux-user: Add support for a group of btrfs ioctls used for snapshots
[qemu.git] / linux-user / mips / cpu_loop.c
1 /*
2 * qemu user cpu loop
3 *
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program 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
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21 #include "qemu-common.h"
22 #include "qemu.h"
23 #include "cpu_loop-common.h"
24 #include "elf.h"
25 #include "internal.h"
26
27 # ifdef TARGET_ABI_MIPSO32
28 # define MIPS_SYSCALL_NUMBER_UNUSED -1
29 static const int8_t mips_syscall_args[] = {
30 #include "syscall-args-o32.c.inc"
31 };
32 # endif /* O32 */
33
34 /* Break codes */
35 enum {
36 BRK_OVERFLOW = 6,
37 BRK_DIVZERO = 7
38 };
39
40 static int do_break(CPUMIPSState *env, target_siginfo_t *info,
41 unsigned int code)
42 {
43 int ret = -1;
44
45 switch (code) {
46 case BRK_OVERFLOW:
47 case BRK_DIVZERO:
48 info->si_signo = TARGET_SIGFPE;
49 info->si_errno = 0;
50 info->si_code = (code == BRK_OVERFLOW) ? FPE_INTOVF : FPE_INTDIV;
51 queue_signal(env, info->si_signo, QEMU_SI_FAULT, &*info);
52 ret = 0;
53 break;
54 default:
55 info->si_signo = TARGET_SIGTRAP;
56 info->si_errno = 0;
57 queue_signal(env, info->si_signo, QEMU_SI_FAULT, &*info);
58 ret = 0;
59 break;
60 }
61
62 return ret;
63 }
64
65 void cpu_loop(CPUMIPSState *env)
66 {
67 CPUState *cs = env_cpu(env);
68 target_siginfo_t info;
69 int trapnr;
70 abi_long ret;
71 # ifdef TARGET_ABI_MIPSO32
72 unsigned int syscall_num;
73 # endif
74
75 for(;;) {
76 cpu_exec_start(cs);
77 trapnr = cpu_exec(cs);
78 cpu_exec_end(cs);
79 process_queued_cpu_work(cs);
80
81 switch(trapnr) {
82 case EXCP_SYSCALL:
83 env->active_tc.PC += 4;
84 # ifdef TARGET_ABI_MIPSO32
85 syscall_num = env->active_tc.gpr[2] - 4000;
86 if (syscall_num >= sizeof(mips_syscall_args)) {
87 /* syscall_num is larger that any defined for MIPS O32 */
88 ret = -TARGET_ENOSYS;
89 } else if (mips_syscall_args[syscall_num] ==
90 MIPS_SYSCALL_NUMBER_UNUSED) {
91 /* syscall_num belongs to the range not defined for MIPS O32 */
92 ret = -TARGET_ENOSYS;
93 } else {
94 /* syscall_num is valid */
95 int nb_args;
96 abi_ulong sp_reg;
97 abi_ulong arg5 = 0, arg6 = 0, arg7 = 0, arg8 = 0;
98
99 nb_args = mips_syscall_args[syscall_num];
100 sp_reg = env->active_tc.gpr[29];
101 switch (nb_args) {
102 /* these arguments are taken from the stack */
103 case 8:
104 if ((ret = get_user_ual(arg8, sp_reg + 28)) != 0) {
105 goto done_syscall;
106 }
107 case 7:
108 if ((ret = get_user_ual(arg7, sp_reg + 24)) != 0) {
109 goto done_syscall;
110 }
111 case 6:
112 if ((ret = get_user_ual(arg6, sp_reg + 20)) != 0) {
113 goto done_syscall;
114 }
115 case 5:
116 if ((ret = get_user_ual(arg5, sp_reg + 16)) != 0) {
117 goto done_syscall;
118 }
119 default:
120 break;
121 }
122 ret = do_syscall(env, env->active_tc.gpr[2],
123 env->active_tc.gpr[4],
124 env->active_tc.gpr[5],
125 env->active_tc.gpr[6],
126 env->active_tc.gpr[7],
127 arg5, arg6, arg7, arg8);
128 }
129 done_syscall:
130 # else
131 ret = do_syscall(env, env->active_tc.gpr[2],
132 env->active_tc.gpr[4], env->active_tc.gpr[5],
133 env->active_tc.gpr[6], env->active_tc.gpr[7],
134 env->active_tc.gpr[8], env->active_tc.gpr[9],
135 env->active_tc.gpr[10], env->active_tc.gpr[11]);
136 # endif /* O32 */
137 if (ret == -TARGET_ERESTARTSYS) {
138 env->active_tc.PC -= 4;
139 break;
140 }
141 if (ret == -TARGET_QEMU_ESIGRETURN) {
142 /* Returning from a successful sigreturn syscall.
143 Avoid clobbering register state. */
144 break;
145 }
146 if ((abi_ulong)ret >= (abi_ulong)-1133) {
147 env->active_tc.gpr[7] = 1; /* error flag */
148 ret = -ret;
149 } else {
150 env->active_tc.gpr[7] = 0; /* error flag */
151 }
152 env->active_tc.gpr[2] = ret;
153 break;
154 case EXCP_TLBL:
155 case EXCP_TLBS:
156 case EXCP_AdEL:
157 case EXCP_AdES:
158 info.si_signo = TARGET_SIGSEGV;
159 info.si_errno = 0;
160 /* XXX: check env->error_code */
161 info.si_code = TARGET_SEGV_MAPERR;
162 info._sifields._sigfault._addr = env->CP0_BadVAddr;
163 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
164 break;
165 case EXCP_CpU:
166 case EXCP_RI:
167 info.si_signo = TARGET_SIGILL;
168 info.si_errno = 0;
169 info.si_code = 0;
170 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
171 break;
172 case EXCP_INTERRUPT:
173 /* just indicate that signals should be handled asap */
174 break;
175 case EXCP_DEBUG:
176 info.si_signo = TARGET_SIGTRAP;
177 info.si_errno = 0;
178 info.si_code = TARGET_TRAP_BRKPT;
179 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
180 break;
181 case EXCP_DSPDIS:
182 info.si_signo = TARGET_SIGILL;
183 info.si_errno = 0;
184 info.si_code = TARGET_ILL_ILLOPC;
185 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
186 break;
187 case EXCP_FPE:
188 info.si_signo = TARGET_SIGFPE;
189 info.si_errno = 0;
190 info.si_code = TARGET_FPE_FLTUNK;
191 if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_INVALID) {
192 info.si_code = TARGET_FPE_FLTINV;
193 } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_DIV0) {
194 info.si_code = TARGET_FPE_FLTDIV;
195 } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_OVERFLOW) {
196 info.si_code = TARGET_FPE_FLTOVF;
197 } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_UNDERFLOW) {
198 info.si_code = TARGET_FPE_FLTUND;
199 } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_INEXACT) {
200 info.si_code = TARGET_FPE_FLTRES;
201 }
202 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
203 break;
204 /* The code below was inspired by the MIPS Linux kernel trap
205 * handling code in arch/mips/kernel/traps.c.
206 */
207 case EXCP_BREAK:
208 {
209 abi_ulong trap_instr;
210 unsigned int code;
211
212 if (env->hflags & MIPS_HFLAG_M16) {
213 if (env->insn_flags & ASE_MICROMIPS) {
214 /* microMIPS mode */
215 ret = get_user_u16(trap_instr, env->active_tc.PC);
216 if (ret != 0) {
217 goto error;
218 }
219
220 if ((trap_instr >> 10) == 0x11) {
221 /* 16-bit instruction */
222 code = trap_instr & 0xf;
223 } else {
224 /* 32-bit instruction */
225 abi_ulong instr_lo;
226
227 ret = get_user_u16(instr_lo,
228 env->active_tc.PC + 2);
229 if (ret != 0) {
230 goto error;
231 }
232 trap_instr = (trap_instr << 16) | instr_lo;
233 code = ((trap_instr >> 6) & ((1 << 20) - 1));
234 /* Unfortunately, microMIPS also suffers from
235 the old assembler bug... */
236 if (code >= (1 << 10)) {
237 code >>= 10;
238 }
239 }
240 } else {
241 /* MIPS16e mode */
242 ret = get_user_u16(trap_instr, env->active_tc.PC);
243 if (ret != 0) {
244 goto error;
245 }
246 code = (trap_instr >> 6) & 0x3f;
247 }
248 } else {
249 ret = get_user_u32(trap_instr, env->active_tc.PC);
250 if (ret != 0) {
251 goto error;
252 }
253
254 /* As described in the original Linux kernel code, the
255 * below checks on 'code' are to work around an old
256 * assembly bug.
257 */
258 code = ((trap_instr >> 6) & ((1 << 20) - 1));
259 if (code >= (1 << 10)) {
260 code >>= 10;
261 }
262 }
263
264 if (do_break(env, &info, code) != 0) {
265 goto error;
266 }
267 }
268 break;
269 case EXCP_TRAP:
270 {
271 abi_ulong trap_instr;
272 unsigned int code = 0;
273
274 if (env->hflags & MIPS_HFLAG_M16) {
275 /* microMIPS mode */
276 abi_ulong instr[2];
277
278 ret = get_user_u16(instr[0], env->active_tc.PC) ||
279 get_user_u16(instr[1], env->active_tc.PC + 2);
280
281 trap_instr = (instr[0] << 16) | instr[1];
282 } else {
283 ret = get_user_u32(trap_instr, env->active_tc.PC);
284 }
285
286 if (ret != 0) {
287 goto error;
288 }
289
290 /* The immediate versions don't provide a code. */
291 if (!(trap_instr & 0xFC000000)) {
292 if (env->hflags & MIPS_HFLAG_M16) {
293 /* microMIPS mode */
294 code = ((trap_instr >> 12) & ((1 << 4) - 1));
295 } else {
296 code = ((trap_instr >> 6) & ((1 << 10) - 1));
297 }
298 }
299
300 if (do_break(env, &info, code) != 0) {
301 goto error;
302 }
303 }
304 break;
305 case EXCP_ATOMIC:
306 cpu_exec_step_atomic(cs);
307 break;
308 default:
309 error:
310 EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
311 abort();
312 }
313 process_pending_signals(env);
314 }
315 }
316
317 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
318 {
319 CPUState *cpu = env_cpu(env);
320 TaskState *ts = cpu->opaque;
321 struct image_info *info = ts->info;
322 int i;
323
324 struct mode_req {
325 bool single;
326 bool soft;
327 bool fr1;
328 bool frdefault;
329 bool fre;
330 };
331
332 static const struct mode_req fpu_reqs[] = {
333 [MIPS_ABI_FP_ANY] = { true, true, true, true, true },
334 [MIPS_ABI_FP_DOUBLE] = { false, false, false, true, true },
335 [MIPS_ABI_FP_SINGLE] = { true, false, false, false, false },
336 [MIPS_ABI_FP_SOFT] = { false, true, false, false, false },
337 [MIPS_ABI_FP_OLD_64] = { false, false, false, false, false },
338 [MIPS_ABI_FP_XX] = { false, false, true, true, true },
339 [MIPS_ABI_FP_64] = { false, false, true, false, false },
340 [MIPS_ABI_FP_64A] = { false, false, true, false, true }
341 };
342
343 /*
344 * Mode requirements when .MIPS.abiflags is not present in the ELF.
345 * Not present means that everything is acceptable except FR1.
346 */
347 static struct mode_req none_req = { true, true, false, true, true };
348
349 struct mode_req prog_req;
350 struct mode_req interp_req;
351
352 for(i = 0; i < 32; i++) {
353 env->active_tc.gpr[i] = regs->regs[i];
354 }
355 env->active_tc.PC = regs->cp0_epc & ~(target_ulong)1;
356 if (regs->cp0_epc & 1) {
357 env->hflags |= MIPS_HFLAG_M16;
358 }
359
360 #ifdef TARGET_ABI_MIPSO32
361 # define MAX_FP_ABI MIPS_ABI_FP_64A
362 #else
363 # define MAX_FP_ABI MIPS_ABI_FP_SOFT
364 #endif
365 if ((info->fp_abi > MAX_FP_ABI && info->fp_abi != MIPS_ABI_FP_UNKNOWN)
366 || (info->interp_fp_abi > MAX_FP_ABI &&
367 info->interp_fp_abi != MIPS_ABI_FP_UNKNOWN)) {
368 fprintf(stderr, "qemu: Unexpected FPU mode\n");
369 exit(1);
370 }
371
372 prog_req = (info->fp_abi == MIPS_ABI_FP_UNKNOWN) ? none_req
373 : fpu_reqs[info->fp_abi];
374 interp_req = (info->interp_fp_abi == MIPS_ABI_FP_UNKNOWN) ? none_req
375 : fpu_reqs[info->interp_fp_abi];
376
377 prog_req.single &= interp_req.single;
378 prog_req.soft &= interp_req.soft;
379 prog_req.fr1 &= interp_req.fr1;
380 prog_req.frdefault &= interp_req.frdefault;
381 prog_req.fre &= interp_req.fre;
382
383 bool cpu_has_mips_r2_r6 = env->insn_flags & ISA_MIPS32R2 ||
384 env->insn_flags & ISA_MIPS64R2 ||
385 env->insn_flags & ISA_MIPS32R6 ||
386 env->insn_flags & ISA_MIPS64R6;
387
388 if (prog_req.fre && !prog_req.frdefault && !prog_req.fr1) {
389 env->CP0_Config5 |= (1 << CP0C5_FRE);
390 if (env->active_fpu.fcr0 & (1 << FCR0_FREP)) {
391 env->hflags |= MIPS_HFLAG_FRE;
392 }
393 } else if ((prog_req.fr1 && prog_req.frdefault) ||
394 (prog_req.single && !prog_req.frdefault)) {
395 if ((env->active_fpu.fcr0 & (1 << FCR0_F64)
396 && cpu_has_mips_r2_r6) || prog_req.fr1) {
397 env->CP0_Status |= (1 << CP0St_FR);
398 env->hflags |= MIPS_HFLAG_F64;
399 }
400 } else if (!prog_req.fre && !prog_req.frdefault &&
401 !prog_req.fr1 && !prog_req.single && !prog_req.soft) {
402 fprintf(stderr, "qemu: Can't find a matching FPU mode\n");
403 exit(1);
404 }
405
406 if (env->insn_flags & ISA_NANOMIPS32) {
407 return;
408 }
409 if (((info->elf_flags & EF_MIPS_NAN2008) != 0) !=
410 ((env->active_fpu.fcr31 & (1 << FCR31_NAN2008)) != 0)) {
411 if ((env->active_fpu.fcr31_rw_bitmask &
412 (1 << FCR31_NAN2008)) == 0) {
413 fprintf(stderr, "ELF binary's NaN mode not supported by CPU\n");
414 exit(1);
415 }
416 if ((info->elf_flags & EF_MIPS_NAN2008) != 0) {
417 env->active_fpu.fcr31 |= (1 << FCR31_NAN2008);
418 } else {
419 env->active_fpu.fcr31 &= ~(1 << FCR31_NAN2008);
420 }
421 restore_snan_bit_mode(env);
422 }
423 }