ppc: Fix sign extension issue in mtmsr(d) emulation
[qemu.git] / linux-user / qemu.h
1 #ifndef QEMU_H
2 #define QEMU_H
3
4 #include "hostdep.h"
5 #include "cpu.h"
6 #include "exec/exec-all.h"
7 #include "exec/cpu_ldst.h"
8
9 #undef DEBUG_REMAP
10 #ifdef DEBUG_REMAP
11 #endif /* DEBUG_REMAP */
12
13 #include "exec/user/abitypes.h"
14
15 #include "exec/user/thunk.h"
16 #include "syscall_defs.h"
17 #include "target_syscall.h"
18 #include "exec/gdbstub.h"
19 #include "qemu/queue.h"
20
21 #define THREAD __thread
22
23 /* This struct is used to hold certain information about the image.
24 * Basically, it replicates in user space what would be certain
25 * task_struct fields in the kernel
26 */
27 struct image_info {
28 abi_ulong load_bias;
29 abi_ulong load_addr;
30 abi_ulong start_code;
31 abi_ulong end_code;
32 abi_ulong start_data;
33 abi_ulong end_data;
34 abi_ulong start_brk;
35 abi_ulong brk;
36 abi_ulong start_mmap;
37 abi_ulong start_stack;
38 abi_ulong stack_limit;
39 abi_ulong entry;
40 abi_ulong code_offset;
41 abi_ulong data_offset;
42 abi_ulong saved_auxv;
43 abi_ulong auxv_len;
44 abi_ulong arg_start;
45 abi_ulong arg_end;
46 uint32_t elf_flags;
47 int personality;
48 #ifdef CONFIG_USE_FDPIC
49 abi_ulong loadmap_addr;
50 uint16_t nsegs;
51 void *loadsegs;
52 abi_ulong pt_dynamic_addr;
53 struct image_info *other_info;
54 #endif
55 };
56
57 #ifdef TARGET_I386
58 /* Information about the current linux thread */
59 struct vm86_saved_state {
60 uint32_t eax; /* return code */
61 uint32_t ebx;
62 uint32_t ecx;
63 uint32_t edx;
64 uint32_t esi;
65 uint32_t edi;
66 uint32_t ebp;
67 uint32_t esp;
68 uint32_t eflags;
69 uint32_t eip;
70 uint16_t cs, ss, ds, es, fs, gs;
71 };
72 #endif
73
74 #if defined(TARGET_ARM) && defined(TARGET_ABI32)
75 /* FPU emulator */
76 #include "nwfpe/fpa11.h"
77 #endif
78
79 #define MAX_SIGQUEUE_SIZE 1024
80
81 struct sigqueue {
82 struct sigqueue *next;
83 target_siginfo_t info;
84 };
85
86 struct emulated_sigtable {
87 int pending; /* true if signal is pending */
88 struct sigqueue *first;
89 struct sigqueue info; /* in order to always have memory for the
90 first signal, we put it here */
91 };
92
93 /* NOTE: we force a big alignment so that the stack stored after is
94 aligned too */
95 typedef struct TaskState {
96 pid_t ts_tid; /* tid (or pid) of this task */
97 #ifdef TARGET_ARM
98 # ifdef TARGET_ABI32
99 /* FPA state */
100 FPA11 fpa;
101 # endif
102 int swi_errno;
103 #endif
104 #ifdef TARGET_UNICORE32
105 int swi_errno;
106 #endif
107 #if defined(TARGET_I386) && !defined(TARGET_X86_64)
108 abi_ulong target_v86;
109 struct vm86_saved_state vm86_saved_regs;
110 struct target_vm86plus_struct vm86plus;
111 uint32_t v86flags;
112 uint32_t v86mask;
113 #endif
114 abi_ulong child_tidptr;
115 #ifdef TARGET_M68K
116 int sim_syscalls;
117 abi_ulong tp_value;
118 #endif
119 #if defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_UNICORE32)
120 /* Extra fields for semihosted binaries. */
121 uint32_t heap_base;
122 uint32_t heap_limit;
123 #endif
124 uint32_t stack_base;
125 int used; /* non zero if used */
126 bool sigsegv_blocked; /* SIGSEGV blocked by guest */
127 struct image_info *info;
128 struct linux_binprm *bprm;
129
130 struct emulated_sigtable sigtab[TARGET_NSIG];
131 struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */
132 struct sigqueue *first_free; /* first free siginfo queue entry */
133 int signal_pending; /* non zero if a signal may be pending */
134 } __attribute__((aligned(16))) TaskState;
135
136 extern char *exec_path;
137 void init_task_state(TaskState *ts);
138 void task_settid(TaskState *);
139 void stop_all_tasks(void);
140 extern const char *qemu_uname_release;
141 extern unsigned long mmap_min_addr;
142
143 /* ??? See if we can avoid exposing so much of the loader internals. */
144
145 /* Read a good amount of data initially, to hopefully get all the
146 program headers loaded. */
147 #define BPRM_BUF_SIZE 1024
148
149 /*
150 * This structure is used to hold the arguments that are
151 * used when loading binaries.
152 */
153 struct linux_binprm {
154 char buf[BPRM_BUF_SIZE] __attribute__((aligned));
155 abi_ulong p;
156 int fd;
157 int e_uid, e_gid;
158 int argc, envc;
159 char **argv;
160 char **envp;
161 char * filename; /* Name of binary */
162 int (*core_dump)(int, const CPUArchState *); /* coredump routine */
163 };
164
165 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
166 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
167 abi_ulong stringp, int push_ptr);
168 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
169 struct target_pt_regs * regs, struct image_info *infop,
170 struct linux_binprm *);
171
172 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
173 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
174
175 abi_long memcpy_to_target(abi_ulong dest, const void *src,
176 unsigned long len);
177 void target_set_brk(abi_ulong new_brk);
178 abi_long do_brk(abi_ulong new_brk);
179 void syscall_init(void);
180 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
181 abi_long arg2, abi_long arg3, abi_long arg4,
182 abi_long arg5, abi_long arg6, abi_long arg7,
183 abi_long arg8);
184 void gemu_log(const char *fmt, ...) GCC_FMT_ATTR(1, 2);
185 extern THREAD CPUState *thread_cpu;
186 void cpu_loop(CPUArchState *env);
187 char *target_strerror(int err);
188 int get_osversion(void);
189 void init_qemu_uname_release(void);
190 void fork_start(void);
191 void fork_end(int child);
192
193 /* Creates the initial guest address space in the host memory space using
194 * the given host start address hint and size. The guest_start parameter
195 * specifies the start address of the guest space. guest_base will be the
196 * difference between the host start address computed by this function and
197 * guest_start. If fixed is specified, then the mapped address space must
198 * start at host_start. The real start address of the mapped memory space is
199 * returned or -1 if there was an error.
200 */
201 unsigned long init_guest_space(unsigned long host_start,
202 unsigned long host_size,
203 unsigned long guest_start,
204 bool fixed);
205
206 #include "qemu/log.h"
207
208 /* safe_syscall.S */
209
210 /**
211 * safe_syscall:
212 * @int number: number of system call to make
213 * ...: arguments to the system call
214 *
215 * Call a system call if guest signal not pending.
216 * This has the same API as the libc syscall() function, except that it
217 * may return -1 with errno == TARGET_ERESTARTSYS if a signal was pending.
218 *
219 * Returns: the system call result, or -1 with an error code in errno
220 * (Errnos are host errnos; we rely on TARGET_ERESTARTSYS not clashing
221 * with any of the host errno values.)
222 */
223
224 /* A guide to using safe_syscall() to handle interactions between guest
225 * syscalls and guest signals:
226 *
227 * Guest syscalls come in two flavours:
228 *
229 * (1) Non-interruptible syscalls
230 *
231 * These are guest syscalls that never get interrupted by signals and
232 * so never return EINTR. They can be implemented straightforwardly in
233 * QEMU: just make sure that if the implementation code has to make any
234 * blocking calls that those calls are retried if they return EINTR.
235 * It's also OK to implement these with safe_syscall, though it will be
236 * a little less efficient if a signal is delivered at the 'wrong' moment.
237 *
238 * (2) Interruptible syscalls
239 *
240 * These are guest syscalls that can be interrupted by signals and
241 * for which we need to either return EINTR or arrange for the guest
242 * syscall to be restarted. This category includes both syscalls which
243 * always restart (and in the kernel return -ERESTARTNOINTR), ones
244 * which only restart if there is no handler (kernel returns -ERESTARTNOHAND
245 * or -ERESTART_RESTARTBLOCK), and the most common kind which restart
246 * if the handler was registered with SA_RESTART (kernel returns
247 * -ERESTARTSYS). System calls which are only interruptible in some
248 * situations (like 'open') also need to be handled this way.
249 *
250 * Here it is important that the host syscall is made
251 * via this safe_syscall() function, and *not* via the host libc.
252 * If the host libc is used then the implementation will appear to work
253 * most of the time, but there will be a race condition where a
254 * signal could arrive just before we make the host syscall inside libc,
255 * and then then guest syscall will not correctly be interrupted.
256 * Instead the implementation of the guest syscall can use the safe_syscall
257 * function but otherwise just return the result or errno in the usual
258 * way; the main loop code will take care of restarting the syscall
259 * if appropriate.
260 *
261 * (If the implementation needs to make multiple host syscalls this is
262 * OK; any which might really block must be via safe_syscall(); for those
263 * which are only technically blocking (ie which we know in practice won't
264 * stay in the host kernel indefinitely) it's OK to use libc if necessary.
265 * You must be able to cope with backing out correctly if some safe_syscall
266 * you make in the implementation returns either -TARGET_ERESTARTSYS or
267 * EINTR though.)
268 *
269 *
270 * How and why the safe_syscall implementation works:
271 *
272 * The basic setup is that we make the host syscall via a known
273 * section of host native assembly. If a signal occurs, our signal
274 * handler checks the interrupted host PC against the addresse of that
275 * known section. If the PC is before or at the address of the syscall
276 * instruction then we change the PC to point at a "return
277 * -TARGET_ERESTARTSYS" code path instead, and then exit the signal handler
278 * (causing the safe_syscall() call to immediately return that value).
279 * Then in the main.c loop if we see this magic return value we adjust
280 * the guest PC to wind it back to before the system call, and invoke
281 * the guest signal handler as usual.
282 *
283 * This winding-back will happen in two cases:
284 * (1) signal came in just before we took the host syscall (a race);
285 * in this case we'll take the guest signal and have another go
286 * at the syscall afterwards, and this is indistinguishable for the
287 * guest from the timing having been different such that the guest
288 * signal really did win the race
289 * (2) signal came in while the host syscall was blocking, and the
290 * host kernel decided the syscall should be restarted;
291 * in this case we want to restart the guest syscall also, and so
292 * rewinding is the right thing. (Note that "restart" semantics mean
293 * "first call the signal handler, then reattempt the syscall".)
294 * The other situation to consider is when a signal came in while the
295 * host syscall was blocking, and the host kernel decided that the syscall
296 * should not be restarted; in this case QEMU's host signal handler will
297 * be invoked with the PC pointing just after the syscall instruction,
298 * with registers indicating an EINTR return; the special code in the
299 * handler will not kick in, and we will return EINTR to the guest as
300 * we should.
301 *
302 * Notice that we can leave the host kernel to make the decision for
303 * us about whether to do a restart of the syscall or not; we do not
304 * need to check SA_RESTART flags in QEMU or distinguish the various
305 * kinds of restartability.
306 */
307 #ifdef HAVE_SAFE_SYSCALL
308 /* The core part of this function is implemented in assembly */
309 extern long safe_syscall_base(int *pending, long number, ...);
310
311 #define safe_syscall(...) \
312 ({ \
313 long ret_; \
314 int *psp_ = &((TaskState *)thread_cpu->opaque)->signal_pending; \
315 ret_ = safe_syscall_base(psp_, __VA_ARGS__); \
316 if (is_error(ret_)) { \
317 errno = -ret_; \
318 ret_ = -1; \
319 } \
320 ret_; \
321 })
322
323 #else
324
325 /* Fallback for architectures which don't yet provide a safe-syscall assembly
326 * fragment; note that this is racy!
327 * This should go away when all host architectures have been updated.
328 */
329 #define safe_syscall syscall
330
331 #endif
332
333 /* syscall.c */
334 int host_to_target_waitstatus(int status);
335
336 /* strace.c */
337 void print_syscall(int num,
338 abi_long arg1, abi_long arg2, abi_long arg3,
339 abi_long arg4, abi_long arg5, abi_long arg6);
340 void print_syscall_ret(int num, abi_long arg1);
341 extern int do_strace;
342
343 /* signal.c */
344 void process_pending_signals(CPUArchState *cpu_env);
345 void signal_init(void);
346 int queue_signal(CPUArchState *env, int sig, target_siginfo_t *info);
347 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
348 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
349 int target_to_host_signal(int sig);
350 int host_to_target_signal(int sig);
351 long do_sigreturn(CPUArchState *env);
352 long do_rt_sigreturn(CPUArchState *env);
353 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
354 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
355
356 #ifdef TARGET_I386
357 /* vm86.c */
358 void save_v86_state(CPUX86State *env);
359 void handle_vm86_trap(CPUX86State *env, int trapno);
360 void handle_vm86_fault(CPUX86State *env);
361 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
362 #elif defined(TARGET_SPARC64)
363 void sparc64_set_context(CPUSPARCState *env);
364 void sparc64_get_context(CPUSPARCState *env);
365 #endif
366
367 /* mmap.c */
368 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
369 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
370 int flags, int fd, abi_ulong offset);
371 int target_munmap(abi_ulong start, abi_ulong len);
372 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
373 abi_ulong new_size, unsigned long flags,
374 abi_ulong new_addr);
375 int target_msync(abi_ulong start, abi_ulong len, int flags);
376 extern unsigned long last_brk;
377 extern abi_ulong mmap_next_start;
378 abi_ulong mmap_find_vma(abi_ulong, abi_ulong);
379 void cpu_list_lock(void);
380 void cpu_list_unlock(void);
381 void mmap_fork_start(void);
382 void mmap_fork_end(int child);
383
384 /* main.c */
385 extern unsigned long guest_stack_size;
386
387 /* user access */
388
389 #define VERIFY_READ 0
390 #define VERIFY_WRITE 1 /* implies read access */
391
392 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
393 {
394 return page_check_range((target_ulong)addr, size,
395 (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
396 }
397
398 /* NOTE __get_user and __put_user use host pointers and don't check access.
399 These are usually used to access struct data members once the struct has
400 been locked - usually with lock_user_struct. */
401
402 /* Tricky points:
403 - Use __builtin_choose_expr to avoid type promotion from ?:,
404 - Invalid sizes result in a compile time error stemming from
405 the fact that abort has no parameters.
406 - It's easier to use the endian-specific unaligned load/store
407 functions than host-endian unaligned load/store plus tswapN. */
408
409 #define __put_user_e(x, hptr, e) \
410 (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p, \
411 __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p, \
412 __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p, \
413 __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort)))) \
414 ((hptr), (x)), (void)0)
415
416 #define __get_user_e(x, hptr, e) \
417 ((x) = (typeof(*hptr))( \
418 __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p, \
419 __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p, \
420 __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p, \
421 __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort)))) \
422 (hptr)), (void)0)
423
424 #ifdef TARGET_WORDS_BIGENDIAN
425 # define __put_user(x, hptr) __put_user_e(x, hptr, be)
426 # define __get_user(x, hptr) __get_user_e(x, hptr, be)
427 #else
428 # define __put_user(x, hptr) __put_user_e(x, hptr, le)
429 # define __get_user(x, hptr) __get_user_e(x, hptr, le)
430 #endif
431
432 /* put_user()/get_user() take a guest address and check access */
433 /* These are usually used to access an atomic data type, such as an int,
434 * that has been passed by address. These internally perform locking
435 * and unlocking on the data type.
436 */
437 #define put_user(x, gaddr, target_type) \
438 ({ \
439 abi_ulong __gaddr = (gaddr); \
440 target_type *__hptr; \
441 abi_long __ret = 0; \
442 if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
443 __put_user((x), __hptr); \
444 unlock_user(__hptr, __gaddr, sizeof(target_type)); \
445 } else \
446 __ret = -TARGET_EFAULT; \
447 __ret; \
448 })
449
450 #define get_user(x, gaddr, target_type) \
451 ({ \
452 abi_ulong __gaddr = (gaddr); \
453 target_type *__hptr; \
454 abi_long __ret = 0; \
455 if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
456 __get_user((x), __hptr); \
457 unlock_user(__hptr, __gaddr, 0); \
458 } else { \
459 /* avoid warning */ \
460 (x) = 0; \
461 __ret = -TARGET_EFAULT; \
462 } \
463 __ret; \
464 })
465
466 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
467 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
468 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
469 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
470 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
471 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
472 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
473 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
474 #define put_user_u8(x, gaddr) put_user((x), (gaddr), uint8_t)
475 #define put_user_s8(x, gaddr) put_user((x), (gaddr), int8_t)
476
477 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
478 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
479 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
480 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
481 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
482 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
483 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
484 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
485 #define get_user_u8(x, gaddr) get_user((x), (gaddr), uint8_t)
486 #define get_user_s8(x, gaddr) get_user((x), (gaddr), int8_t)
487
488 /* copy_from_user() and copy_to_user() are usually used to copy data
489 * buffers between the target and host. These internally perform
490 * locking/unlocking of the memory.
491 */
492 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
493 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
494
495 /* Functions for accessing guest memory. The tget and tput functions
496 read/write single values, byteswapping as necessary. The lock_user function
497 gets a pointer to a contiguous area of guest memory, but does not perform
498 any byteswapping. lock_user may return either a pointer to the guest
499 memory, or a temporary buffer. */
500
501 /* Lock an area of guest memory into the host. If copy is true then the
502 host area will have the same contents as the guest. */
503 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
504 {
505 if (!access_ok(type, guest_addr, len))
506 return NULL;
507 #ifdef DEBUG_REMAP
508 {
509 void *addr;
510 addr = malloc(len);
511 if (copy)
512 memcpy(addr, g2h(guest_addr), len);
513 else
514 memset(addr, 0, len);
515 return addr;
516 }
517 #else
518 return g2h(guest_addr);
519 #endif
520 }
521
522 /* Unlock an area of guest memory. The first LEN bytes must be
523 flushed back to guest memory. host_ptr = NULL is explicitly
524 allowed and does nothing. */
525 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
526 long len)
527 {
528
529 #ifdef DEBUG_REMAP
530 if (!host_ptr)
531 return;
532 if (host_ptr == g2h(guest_addr))
533 return;
534 if (len > 0)
535 memcpy(g2h(guest_addr), host_ptr, len);
536 free(host_ptr);
537 #endif
538 }
539
540 /* Return the length of a string in target memory or -TARGET_EFAULT if
541 access error. */
542 abi_long target_strlen(abi_ulong gaddr);
543
544 /* Like lock_user but for null terminated strings. */
545 static inline void *lock_user_string(abi_ulong guest_addr)
546 {
547 abi_long len;
548 len = target_strlen(guest_addr);
549 if (len < 0)
550 return NULL;
551 return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
552 }
553
554 /* Helper macros for locking/unlocking a target struct. */
555 #define lock_user_struct(type, host_ptr, guest_addr, copy) \
556 (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
557 #define unlock_user_struct(host_ptr, guest_addr, copy) \
558 unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
559
560 #include <pthread.h>
561
562 /* Include target-specific struct and function definitions;
563 * they may need access to the target-independent structures
564 * above, so include them last.
565 */
566 #include "target_cpu.h"
567 #include "target_signal.h"
568 #include "target_structs.h"
569
570 #endif /* QEMU_H */