ef400cb78ac67e4ae95503f6e21f8377ec375f46
[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 /* This is the size of the host kernel's sigset_t, needed where we make
22 * direct system calls that take a sigset_t pointer and a size.
23 */
24 #define SIGSET_T_SIZE (_NSIG / 8)
25
26 /* This struct is used to hold certain information about the image.
27 * Basically, it replicates in user space what would be certain
28 * task_struct fields in the kernel
29 */
30 struct image_info {
31 abi_ulong load_bias;
32 abi_ulong load_addr;
33 abi_ulong start_code;
34 abi_ulong end_code;
35 abi_ulong start_data;
36 abi_ulong end_data;
37 abi_ulong start_brk;
38 abi_ulong brk;
39 abi_ulong start_mmap;
40 abi_ulong start_stack;
41 abi_ulong stack_limit;
42 abi_ulong entry;
43 abi_ulong code_offset;
44 abi_ulong data_offset;
45 abi_ulong saved_auxv;
46 abi_ulong auxv_len;
47 abi_ulong arg_start;
48 abi_ulong arg_end;
49 abi_ulong arg_strings;
50 abi_ulong env_strings;
51 abi_ulong file_string;
52 uint32_t elf_flags;
53 int personality;
54 abi_ulong alignment;
55
56 /* The fields below are used in FDPIC mode. */
57 abi_ulong loadmap_addr;
58 uint16_t nsegs;
59 void *loadsegs;
60 abi_ulong pt_dynamic_addr;
61 abi_ulong interpreter_loadmap_addr;
62 abi_ulong interpreter_pt_dynamic_addr;
63 struct image_info *other_info;
64 #ifdef TARGET_MIPS
65 int fp_abi;
66 int interp_fp_abi;
67 #endif
68 };
69
70 #ifdef TARGET_I386
71 /* Information about the current linux thread */
72 struct vm86_saved_state {
73 uint32_t eax; /* return code */
74 uint32_t ebx;
75 uint32_t ecx;
76 uint32_t edx;
77 uint32_t esi;
78 uint32_t edi;
79 uint32_t ebp;
80 uint32_t esp;
81 uint32_t eflags;
82 uint32_t eip;
83 uint16_t cs, ss, ds, es, fs, gs;
84 };
85 #endif
86
87 #if defined(TARGET_ARM) && defined(TARGET_ABI32)
88 /* FPU emulator */
89 #include "nwfpe/fpa11.h"
90 #endif
91
92 #define MAX_SIGQUEUE_SIZE 1024
93
94 struct emulated_sigtable {
95 int pending; /* true if signal is pending */
96 target_siginfo_t info;
97 };
98
99 /* NOTE: we force a big alignment so that the stack stored after is
100 aligned too */
101 typedef struct TaskState {
102 pid_t ts_tid; /* tid (or pid) of this task */
103 #ifdef TARGET_ARM
104 # ifdef TARGET_ABI32
105 /* FPA state */
106 FPA11 fpa;
107 # endif
108 int swi_errno;
109 #endif
110 #if defined(TARGET_I386) && !defined(TARGET_X86_64)
111 abi_ulong target_v86;
112 struct vm86_saved_state vm86_saved_regs;
113 struct target_vm86plus_struct vm86plus;
114 uint32_t v86flags;
115 uint32_t v86mask;
116 #endif
117 abi_ulong child_tidptr;
118 #ifdef TARGET_M68K
119 int sim_syscalls;
120 abi_ulong tp_value;
121 #endif
122 #if defined(TARGET_ARM) || defined(TARGET_M68K)
123 /* Extra fields for semihosted binaries. */
124 abi_ulong heap_base;
125 abi_ulong heap_limit;
126 #endif
127 abi_ulong stack_base;
128 int used; /* non zero if used */
129 struct image_info *info;
130 struct linux_binprm *bprm;
131
132 struct emulated_sigtable sync_signal;
133 struct emulated_sigtable sigtab[TARGET_NSIG];
134 /* This thread's signal mask, as requested by the guest program.
135 * The actual signal mask of this thread may differ:
136 * + we don't let SIGSEGV and SIGBUS be blocked while running guest code
137 * + sometimes we block all signals to avoid races
138 */
139 sigset_t signal_mask;
140 /* The signal mask imposed by a guest sigsuspend syscall, if we are
141 * currently in the middle of such a syscall
142 */
143 sigset_t sigsuspend_mask;
144 /* Nonzero if we're leaving a sigsuspend and sigsuspend_mask is valid. */
145 int in_sigsuspend;
146
147 /* Nonzero if process_pending_signals() needs to do something (either
148 * handle a pending signal or unblock signals).
149 * This flag is written from a signal handler so should be accessed via
150 * the atomic_read() and atomic_set() functions. (It is not accessed
151 * from multiple threads.)
152 */
153 int signal_pending;
154
155 } __attribute__((aligned(16))) TaskState;
156
157 extern char *exec_path;
158 void init_task_state(TaskState *ts);
159 void task_settid(TaskState *);
160 void stop_all_tasks(void);
161 extern const char *qemu_uname_release;
162 extern unsigned long mmap_min_addr;
163
164 /* ??? See if we can avoid exposing so much of the loader internals. */
165
166 /* Read a good amount of data initially, to hopefully get all the
167 program headers loaded. */
168 #define BPRM_BUF_SIZE 1024
169
170 /*
171 * This structure is used to hold the arguments that are
172 * used when loading binaries.
173 */
174 struct linux_binprm {
175 char buf[BPRM_BUF_SIZE] __attribute__((aligned));
176 abi_ulong p;
177 int fd;
178 int e_uid, e_gid;
179 int argc, envc;
180 char **argv;
181 char **envp;
182 char * filename; /* Name of binary */
183 int (*core_dump)(int, const CPUArchState *); /* coredump routine */
184 };
185
186 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
187 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
188 abi_ulong stringp, int push_ptr);
189 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
190 struct target_pt_regs * regs, struct image_info *infop,
191 struct linux_binprm *);
192
193 /* Returns true if the image uses the FDPIC ABI. If this is the case,
194 * we have to provide some information (loadmap, pt_dynamic_info) such
195 * that the program can be relocated adequately. This is also useful
196 * when handling signals.
197 */
198 int info_is_fdpic(struct image_info *info);
199
200 uint32_t get_elf_eflags(int fd);
201 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
202 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
203
204 abi_long memcpy_to_target(abi_ulong dest, const void *src,
205 unsigned long len);
206 void target_set_brk(abi_ulong new_brk);
207 abi_long do_brk(abi_ulong new_brk);
208 void syscall_init(void);
209 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
210 abi_long arg2, abi_long arg3, abi_long arg4,
211 abi_long arg5, abi_long arg6, abi_long arg7,
212 abi_long arg8);
213 void gemu_log(const char *fmt, ...) GCC_FMT_ATTR(1, 2);
214 extern __thread CPUState *thread_cpu;
215 void cpu_loop(CPUArchState *env);
216 const char *target_strerror(int err);
217 int get_osversion(void);
218 void init_qemu_uname_release(void);
219 void fork_start(void);
220 void fork_end(int child);
221
222 /* Creates the initial guest address space in the host memory space using
223 * the given host start address hint and size. The guest_start parameter
224 * specifies the start address of the guest space. guest_base will be the
225 * difference between the host start address computed by this function and
226 * guest_start. If fixed is specified, then the mapped address space must
227 * start at host_start. The real start address of the mapped memory space is
228 * returned or -1 if there was an error.
229 */
230 unsigned long init_guest_space(unsigned long host_start,
231 unsigned long host_size,
232 unsigned long guest_start,
233 bool fixed);
234
235 #include "qemu/log.h"
236
237 /* safe_syscall.S */
238
239 /**
240 * safe_syscall:
241 * @int number: number of system call to make
242 * ...: arguments to the system call
243 *
244 * Call a system call if guest signal not pending.
245 * This has the same API as the libc syscall() function, except that it
246 * may return -1 with errno == TARGET_ERESTARTSYS if a signal was pending.
247 *
248 * Returns: the system call result, or -1 with an error code in errno
249 * (Errnos are host errnos; we rely on TARGET_ERESTARTSYS not clashing
250 * with any of the host errno values.)
251 */
252
253 /* A guide to using safe_syscall() to handle interactions between guest
254 * syscalls and guest signals:
255 *
256 * Guest syscalls come in two flavours:
257 *
258 * (1) Non-interruptible syscalls
259 *
260 * These are guest syscalls that never get interrupted by signals and
261 * so never return EINTR. They can be implemented straightforwardly in
262 * QEMU: just make sure that if the implementation code has to make any
263 * blocking calls that those calls are retried if they return EINTR.
264 * It's also OK to implement these with safe_syscall, though it will be
265 * a little less efficient if a signal is delivered at the 'wrong' moment.
266 *
267 * Some non-interruptible syscalls need to be handled using block_signals()
268 * to block signals for the duration of the syscall. This mainly applies
269 * to code which needs to modify the data structures used by the
270 * host_signal_handler() function and the functions it calls, including
271 * all syscalls which change the thread's signal mask.
272 *
273 * (2) Interruptible syscalls
274 *
275 * These are guest syscalls that can be interrupted by signals and
276 * for which we need to either return EINTR or arrange for the guest
277 * syscall to be restarted. This category includes both syscalls which
278 * always restart (and in the kernel return -ERESTARTNOINTR), ones
279 * which only restart if there is no handler (kernel returns -ERESTARTNOHAND
280 * or -ERESTART_RESTARTBLOCK), and the most common kind which restart
281 * if the handler was registered with SA_RESTART (kernel returns
282 * -ERESTARTSYS). System calls which are only interruptible in some
283 * situations (like 'open') also need to be handled this way.
284 *
285 * Here it is important that the host syscall is made
286 * via this safe_syscall() function, and *not* via the host libc.
287 * If the host libc is used then the implementation will appear to work
288 * most of the time, but there will be a race condition where a
289 * signal could arrive just before we make the host syscall inside libc,
290 * and then then guest syscall will not correctly be interrupted.
291 * Instead the implementation of the guest syscall can use the safe_syscall
292 * function but otherwise just return the result or errno in the usual
293 * way; the main loop code will take care of restarting the syscall
294 * if appropriate.
295 *
296 * (If the implementation needs to make multiple host syscalls this is
297 * OK; any which might really block must be via safe_syscall(); for those
298 * which are only technically blocking (ie which we know in practice won't
299 * stay in the host kernel indefinitely) it's OK to use libc if necessary.
300 * You must be able to cope with backing out correctly if some safe_syscall
301 * you make in the implementation returns either -TARGET_ERESTARTSYS or
302 * EINTR though.)
303 *
304 * block_signals() cannot be used for interruptible syscalls.
305 *
306 *
307 * How and why the safe_syscall implementation works:
308 *
309 * The basic setup is that we make the host syscall via a known
310 * section of host native assembly. If a signal occurs, our signal
311 * handler checks the interrupted host PC against the addresse of that
312 * known section. If the PC is before or at the address of the syscall
313 * instruction then we change the PC to point at a "return
314 * -TARGET_ERESTARTSYS" code path instead, and then exit the signal handler
315 * (causing the safe_syscall() call to immediately return that value).
316 * Then in the main.c loop if we see this magic return value we adjust
317 * the guest PC to wind it back to before the system call, and invoke
318 * the guest signal handler as usual.
319 *
320 * This winding-back will happen in two cases:
321 * (1) signal came in just before we took the host syscall (a race);
322 * in this case we'll take the guest signal and have another go
323 * at the syscall afterwards, and this is indistinguishable for the
324 * guest from the timing having been different such that the guest
325 * signal really did win the race
326 * (2) signal came in while the host syscall was blocking, and the
327 * host kernel decided the syscall should be restarted;
328 * in this case we want to restart the guest syscall also, and so
329 * rewinding is the right thing. (Note that "restart" semantics mean
330 * "first call the signal handler, then reattempt the syscall".)
331 * The other situation to consider is when a signal came in while the
332 * host syscall was blocking, and the host kernel decided that the syscall
333 * should not be restarted; in this case QEMU's host signal handler will
334 * be invoked with the PC pointing just after the syscall instruction,
335 * with registers indicating an EINTR return; the special code in the
336 * handler will not kick in, and we will return EINTR to the guest as
337 * we should.
338 *
339 * Notice that we can leave the host kernel to make the decision for
340 * us about whether to do a restart of the syscall or not; we do not
341 * need to check SA_RESTART flags in QEMU or distinguish the various
342 * kinds of restartability.
343 */
344 #ifdef HAVE_SAFE_SYSCALL
345 /* The core part of this function is implemented in assembly */
346 extern long safe_syscall_base(int *pending, long number, ...);
347
348 #define safe_syscall(...) \
349 ({ \
350 long ret_; \
351 int *psp_ = &((TaskState *)thread_cpu->opaque)->signal_pending; \
352 ret_ = safe_syscall_base(psp_, __VA_ARGS__); \
353 if (is_error(ret_)) { \
354 errno = -ret_; \
355 ret_ = -1; \
356 } \
357 ret_; \
358 })
359
360 #else
361
362 /* Fallback for architectures which don't yet provide a safe-syscall assembly
363 * fragment; note that this is racy!
364 * This should go away when all host architectures have been updated.
365 */
366 #define safe_syscall syscall
367
368 #endif
369
370 /* syscall.c */
371 int host_to_target_waitstatus(int status);
372
373 /* strace.c */
374 void print_syscall(int num,
375 abi_long arg1, abi_long arg2, abi_long arg3,
376 abi_long arg4, abi_long arg5, abi_long arg6);
377 void print_syscall_ret(int num, abi_long arg1);
378 /**
379 * print_taken_signal:
380 * @target_signum: target signal being taken
381 * @tinfo: target_siginfo_t which will be passed to the guest for the signal
382 *
383 * Print strace output indicating that this signal is being taken by the guest,
384 * in a format similar to:
385 * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
386 */
387 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
388 extern int do_strace;
389
390 /* signal.c */
391 void process_pending_signals(CPUArchState *cpu_env);
392 void signal_init(void);
393 int queue_signal(CPUArchState *env, int sig, int si_type,
394 target_siginfo_t *info);
395 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
396 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
397 int target_to_host_signal(int sig);
398 int host_to_target_signal(int sig);
399 long do_sigreturn(CPUArchState *env);
400 long do_rt_sigreturn(CPUArchState *env);
401 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
402 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
403 abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx,
404 abi_ulong unew_ctx, abi_long ctx_size);
405 /**
406 * block_signals: block all signals while handling this guest syscall
407 *
408 * Block all signals, and arrange that the signal mask is returned to
409 * its correct value for the guest before we resume execution of guest code.
410 * If this function returns non-zero, then the caller should immediately
411 * return -TARGET_ERESTARTSYS to the main loop, which will take the pending
412 * signal and restart execution of the syscall.
413 * If block_signals() returns zero, then the caller can continue with
414 * emulation of the system call knowing that no signals can be taken
415 * (and therefore that no race conditions will result).
416 * This should only be called once, because if it is called a second time
417 * it will always return non-zero. (Think of it like a mutex that can't
418 * be recursively locked.)
419 * Signals will be unblocked again by process_pending_signals().
420 *
421 * Return value: non-zero if there was a pending signal, zero if not.
422 */
423 int block_signals(void); /* Returns non zero if signal pending */
424
425 #ifdef TARGET_I386
426 /* vm86.c */
427 void save_v86_state(CPUX86State *env);
428 void handle_vm86_trap(CPUX86State *env, int trapno);
429 void handle_vm86_fault(CPUX86State *env);
430 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
431 #elif defined(TARGET_SPARC64)
432 void sparc64_set_context(CPUSPARCState *env);
433 void sparc64_get_context(CPUSPARCState *env);
434 #endif
435
436 /* mmap.c */
437 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
438 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
439 int flags, int fd, abi_ulong offset);
440 int target_munmap(abi_ulong start, abi_ulong len);
441 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
442 abi_ulong new_size, unsigned long flags,
443 abi_ulong new_addr);
444 extern unsigned long last_brk;
445 extern abi_ulong mmap_next_start;
446 abi_ulong mmap_find_vma(abi_ulong, abi_ulong);
447 void mmap_fork_start(void);
448 void mmap_fork_end(int child);
449
450 /* main.c */
451 extern unsigned long guest_stack_size;
452
453 /* user access */
454
455 #define VERIFY_READ 0
456 #define VERIFY_WRITE 1 /* implies read access */
457
458 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
459 {
460 return page_check_range((target_ulong)addr, size,
461 (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
462 }
463
464 /* NOTE __get_user and __put_user use host pointers and don't check access.
465 These are usually used to access struct data members once the struct has
466 been locked - usually with lock_user_struct. */
467
468 /*
469 * Tricky points:
470 * - Use __builtin_choose_expr to avoid type promotion from ?:,
471 * - Invalid sizes result in a compile time error stemming from
472 * the fact that abort has no parameters.
473 * - It's easier to use the endian-specific unaligned load/store
474 * functions than host-endian unaligned load/store plus tswapN.
475 * - The pragmas are necessary only to silence a clang false-positive
476 * warning: see https://bugs.llvm.org/show_bug.cgi?id=39113 .
477 * - gcc has bugs in its _Pragma() support in some versions, eg
478 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83256 -- so we only
479 * include the warning-suppression pragmas for clang
480 */
481 #if defined(__clang__) && __has_warning("-Waddress-of-packed-member")
482 #define PRAGMA_DISABLE_PACKED_WARNING \
483 _Pragma("GCC diagnostic push"); \
484 _Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"")
485
486 #define PRAGMA_REENABLE_PACKED_WARNING \
487 _Pragma("GCC diagnostic pop")
488
489 #else
490 #define PRAGMA_DISABLE_PACKED_WARNING
491 #define PRAGMA_REENABLE_PACKED_WARNING
492 #endif
493
494 #define __put_user_e(x, hptr, e) \
495 do { \
496 PRAGMA_DISABLE_PACKED_WARNING; \
497 (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p, \
498 __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p, \
499 __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p, \
500 __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort)))) \
501 ((hptr), (x)), (void)0); \
502 PRAGMA_REENABLE_PACKED_WARNING; \
503 } while (0)
504
505 #define __get_user_e(x, hptr, e) \
506 do { \
507 PRAGMA_DISABLE_PACKED_WARNING; \
508 ((x) = (typeof(*hptr))( \
509 __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p, \
510 __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p, \
511 __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p, \
512 __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort)))) \
513 (hptr)), (void)0); \
514 PRAGMA_REENABLE_PACKED_WARNING; \
515 } while (0)
516
517
518 #ifdef TARGET_WORDS_BIGENDIAN
519 # define __put_user(x, hptr) __put_user_e(x, hptr, be)
520 # define __get_user(x, hptr) __get_user_e(x, hptr, be)
521 #else
522 # define __put_user(x, hptr) __put_user_e(x, hptr, le)
523 # define __get_user(x, hptr) __get_user_e(x, hptr, le)
524 #endif
525
526 /* put_user()/get_user() take a guest address and check access */
527 /* These are usually used to access an atomic data type, such as an int,
528 * that has been passed by address. These internally perform locking
529 * and unlocking on the data type.
530 */
531 #define put_user(x, gaddr, target_type) \
532 ({ \
533 abi_ulong __gaddr = (gaddr); \
534 target_type *__hptr; \
535 abi_long __ret = 0; \
536 if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
537 __put_user((x), __hptr); \
538 unlock_user(__hptr, __gaddr, sizeof(target_type)); \
539 } else \
540 __ret = -TARGET_EFAULT; \
541 __ret; \
542 })
543
544 #define get_user(x, gaddr, target_type) \
545 ({ \
546 abi_ulong __gaddr = (gaddr); \
547 target_type *__hptr; \
548 abi_long __ret = 0; \
549 if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
550 __get_user((x), __hptr); \
551 unlock_user(__hptr, __gaddr, 0); \
552 } else { \
553 /* avoid warning */ \
554 (x) = 0; \
555 __ret = -TARGET_EFAULT; \
556 } \
557 __ret; \
558 })
559
560 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
561 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
562 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
563 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
564 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
565 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
566 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
567 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
568 #define put_user_u8(x, gaddr) put_user((x), (gaddr), uint8_t)
569 #define put_user_s8(x, gaddr) put_user((x), (gaddr), int8_t)
570
571 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
572 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
573 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
574 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
575 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
576 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
577 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
578 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
579 #define get_user_u8(x, gaddr) get_user((x), (gaddr), uint8_t)
580 #define get_user_s8(x, gaddr) get_user((x), (gaddr), int8_t)
581
582 /* copy_from_user() and copy_to_user() are usually used to copy data
583 * buffers between the target and host. These internally perform
584 * locking/unlocking of the memory.
585 */
586 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
587 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
588
589 /* Functions for accessing guest memory. The tget and tput functions
590 read/write single values, byteswapping as necessary. The lock_user function
591 gets a pointer to a contiguous area of guest memory, but does not perform
592 any byteswapping. lock_user may return either a pointer to the guest
593 memory, or a temporary buffer. */
594
595 /* Lock an area of guest memory into the host. If copy is true then the
596 host area will have the same contents as the guest. */
597 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
598 {
599 if (!access_ok(type, guest_addr, len))
600 return NULL;
601 #ifdef DEBUG_REMAP
602 {
603 void *addr;
604 addr = g_malloc(len);
605 if (copy)
606 memcpy(addr, g2h(guest_addr), len);
607 else
608 memset(addr, 0, len);
609 return addr;
610 }
611 #else
612 return g2h(guest_addr);
613 #endif
614 }
615
616 /* Unlock an area of guest memory. The first LEN bytes must be
617 flushed back to guest memory. host_ptr = NULL is explicitly
618 allowed and does nothing. */
619 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
620 long len)
621 {
622
623 #ifdef DEBUG_REMAP
624 if (!host_ptr)
625 return;
626 if (host_ptr == g2h(guest_addr))
627 return;
628 if (len > 0)
629 memcpy(g2h(guest_addr), host_ptr, len);
630 g_free(host_ptr);
631 #endif
632 }
633
634 /* Return the length of a string in target memory or -TARGET_EFAULT if
635 access error. */
636 abi_long target_strlen(abi_ulong gaddr);
637
638 /* Like lock_user but for null terminated strings. */
639 static inline void *lock_user_string(abi_ulong guest_addr)
640 {
641 abi_long len;
642 len = target_strlen(guest_addr);
643 if (len < 0)
644 return NULL;
645 return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
646 }
647
648 /* Helper macros for locking/unlocking a target struct. */
649 #define lock_user_struct(type, host_ptr, guest_addr, copy) \
650 (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
651 #define unlock_user_struct(host_ptr, guest_addr, copy) \
652 unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
653
654 #include <pthread.h>
655
656 static inline int is_error(abi_long ret)
657 {
658 return (abi_ulong)ret >= (abi_ulong)(-4096);
659 }
660
661 /**
662 * preexit_cleanup: housekeeping before the guest exits
663 *
664 * env: the CPU state
665 * code: the exit code
666 */
667 void preexit_cleanup(CPUArchState *env, int code);
668
669 /* Include target-specific struct and function definitions;
670 * they may need access to the target-independent structures
671 * above, so include them last.
672 */
673 #include "target_cpu.h"
674 #include "target_structs.h"
675
676 #endif /* QEMU_H */