xref: /openbmc/qemu/linux-user/qemu.h (revision 9cdd2a73)
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 #ifdef CONFIG_USE_FDPIC
55         abi_ulong       loadmap_addr;
56         uint16_t        nsegs;
57         void           *loadsegs;
58         abi_ulong       pt_dynamic_addr;
59         struct image_info *other_info;
60 #endif
61 };
62 
63 #ifdef TARGET_I386
64 /* Information about the current linux thread */
65 struct vm86_saved_state {
66     uint32_t eax; /* return code */
67     uint32_t ebx;
68     uint32_t ecx;
69     uint32_t edx;
70     uint32_t esi;
71     uint32_t edi;
72     uint32_t ebp;
73     uint32_t esp;
74     uint32_t eflags;
75     uint32_t eip;
76     uint16_t cs, ss, ds, es, fs, gs;
77 };
78 #endif
79 
80 #if defined(TARGET_ARM) && defined(TARGET_ABI32)
81 /* FPU emulator */
82 #include "nwfpe/fpa11.h"
83 #endif
84 
85 #define MAX_SIGQUEUE_SIZE 1024
86 
87 struct emulated_sigtable {
88     int pending; /* true if signal is pending */
89     target_siginfo_t info;
90 };
91 
92 /* NOTE: we force a big alignment so that the stack stored after is
93    aligned too */
94 typedef struct TaskState {
95     pid_t ts_tid;     /* tid (or pid) of this task */
96 #ifdef TARGET_ARM
97 # ifdef TARGET_ABI32
98     /* FPA state */
99     FPA11 fpa;
100 # endif
101     int swi_errno;
102 #endif
103 #if defined(TARGET_I386) && !defined(TARGET_X86_64)
104     abi_ulong target_v86;
105     struct vm86_saved_state vm86_saved_regs;
106     struct target_vm86plus_struct vm86plus;
107     uint32_t v86flags;
108     uint32_t v86mask;
109 #endif
110     abi_ulong child_tidptr;
111 #ifdef TARGET_M68K
112     int sim_syscalls;
113     abi_ulong tp_value;
114 #endif
115 #if defined(TARGET_ARM) || defined(TARGET_M68K)
116     /* Extra fields for semihosted binaries.  */
117     abi_ulong heap_base;
118     abi_ulong heap_limit;
119 #endif
120     abi_ulong stack_base;
121     int used; /* non zero if used */
122     struct image_info *info;
123     struct linux_binprm *bprm;
124 
125     struct emulated_sigtable sync_signal;
126     struct emulated_sigtable sigtab[TARGET_NSIG];
127     /* This thread's signal mask, as requested by the guest program.
128      * The actual signal mask of this thread may differ:
129      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
130      *  + sometimes we block all signals to avoid races
131      */
132     sigset_t signal_mask;
133     /* The signal mask imposed by a guest sigsuspend syscall, if we are
134      * currently in the middle of such a syscall
135      */
136     sigset_t sigsuspend_mask;
137     /* Nonzero if we're leaving a sigsuspend and sigsuspend_mask is valid. */
138     int in_sigsuspend;
139 
140     /* Nonzero if process_pending_signals() needs to do something (either
141      * handle a pending signal or unblock signals).
142      * This flag is written from a signal handler so should be accessed via
143      * the atomic_read() and atomic_write() functions. (It is not accessed
144      * from multiple threads.)
145      */
146     int signal_pending;
147 
148 } __attribute__((aligned(16))) TaskState;
149 
150 extern char *exec_path;
151 void init_task_state(TaskState *ts);
152 void task_settid(TaskState *);
153 void stop_all_tasks(void);
154 extern const char *qemu_uname_release;
155 extern unsigned long mmap_min_addr;
156 
157 /* ??? See if we can avoid exposing so much of the loader internals.  */
158 
159 /* Read a good amount of data initially, to hopefully get all the
160    program headers loaded.  */
161 #define BPRM_BUF_SIZE  1024
162 
163 /*
164  * This structure is used to hold the arguments that are
165  * used when loading binaries.
166  */
167 struct linux_binprm {
168         char buf[BPRM_BUF_SIZE] __attribute__((aligned));
169         abi_ulong p;
170 	int fd;
171         int e_uid, e_gid;
172         int argc, envc;
173         char **argv;
174         char **envp;
175         char * filename;        /* Name of binary */
176         int (*core_dump)(int, const CPUArchState *); /* coredump routine */
177 };
178 
179 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
180 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
181                               abi_ulong stringp, int push_ptr);
182 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
183              struct target_pt_regs * regs, struct image_info *infop,
184              struct linux_binprm *);
185 
186 uint32_t get_elf_eflags(int fd);
187 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
188 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
189 
190 abi_long memcpy_to_target(abi_ulong dest, const void *src,
191                           unsigned long len);
192 void target_set_brk(abi_ulong new_brk);
193 abi_long do_brk(abi_ulong new_brk);
194 void syscall_init(void);
195 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
196                     abi_long arg2, abi_long arg3, abi_long arg4,
197                     abi_long arg5, abi_long arg6, abi_long arg7,
198                     abi_long arg8);
199 void gemu_log(const char *fmt, ...) GCC_FMT_ATTR(1, 2);
200 extern __thread CPUState *thread_cpu;
201 void cpu_loop(CPUArchState *env);
202 const char *target_strerror(int err);
203 int get_osversion(void);
204 void init_qemu_uname_release(void);
205 void fork_start(void);
206 void fork_end(int child);
207 
208 /* Creates the initial guest address space in the host memory space using
209  * the given host start address hint and size.  The guest_start parameter
210  * specifies the start address of the guest space.  guest_base will be the
211  * difference between the host start address computed by this function and
212  * guest_start.  If fixed is specified, then the mapped address space must
213  * start at host_start.  The real start address of the mapped memory space is
214  * returned or -1 if there was an error.
215  */
216 unsigned long init_guest_space(unsigned long host_start,
217                                unsigned long host_size,
218                                unsigned long guest_start,
219                                bool fixed);
220 
221 #include "qemu/log.h"
222 
223 /* safe_syscall.S */
224 
225 /**
226  * safe_syscall:
227  * @int number: number of system call to make
228  * ...: arguments to the system call
229  *
230  * Call a system call if guest signal not pending.
231  * This has the same API as the libc syscall() function, except that it
232  * may return -1 with errno == TARGET_ERESTARTSYS if a signal was pending.
233  *
234  * Returns: the system call result, or -1 with an error code in errno
235  * (Errnos are host errnos; we rely on TARGET_ERESTARTSYS not clashing
236  * with any of the host errno values.)
237  */
238 
239 /* A guide to using safe_syscall() to handle interactions between guest
240  * syscalls and guest signals:
241  *
242  * Guest syscalls come in two flavours:
243  *
244  * (1) Non-interruptible syscalls
245  *
246  * These are guest syscalls that never get interrupted by signals and
247  * so never return EINTR. They can be implemented straightforwardly in
248  * QEMU: just make sure that if the implementation code has to make any
249  * blocking calls that those calls are retried if they return EINTR.
250  * It's also OK to implement these with safe_syscall, though it will be
251  * a little less efficient if a signal is delivered at the 'wrong' moment.
252  *
253  * Some non-interruptible syscalls need to be handled using block_signals()
254  * to block signals for the duration of the syscall. This mainly applies
255  * to code which needs to modify the data structures used by the
256  * host_signal_handler() function and the functions it calls, including
257  * all syscalls which change the thread's signal mask.
258  *
259  * (2) Interruptible syscalls
260  *
261  * These are guest syscalls that can be interrupted by signals and
262  * for which we need to either return EINTR or arrange for the guest
263  * syscall to be restarted. This category includes both syscalls which
264  * always restart (and in the kernel return -ERESTARTNOINTR), ones
265  * which only restart if there is no handler (kernel returns -ERESTARTNOHAND
266  * or -ERESTART_RESTARTBLOCK), and the most common kind which restart
267  * if the handler was registered with SA_RESTART (kernel returns
268  * -ERESTARTSYS). System calls which are only interruptible in some
269  * situations (like 'open') also need to be handled this way.
270  *
271  * Here it is important that the host syscall is made
272  * via this safe_syscall() function, and *not* via the host libc.
273  * If the host libc is used then the implementation will appear to work
274  * most of the time, but there will be a race condition where a
275  * signal could arrive just before we make the host syscall inside libc,
276  * and then then guest syscall will not correctly be interrupted.
277  * Instead the implementation of the guest syscall can use the safe_syscall
278  * function but otherwise just return the result or errno in the usual
279  * way; the main loop code will take care of restarting the syscall
280  * if appropriate.
281  *
282  * (If the implementation needs to make multiple host syscalls this is
283  * OK; any which might really block must be via safe_syscall(); for those
284  * which are only technically blocking (ie which we know in practice won't
285  * stay in the host kernel indefinitely) it's OK to use libc if necessary.
286  * You must be able to cope with backing out correctly if some safe_syscall
287  * you make in the implementation returns either -TARGET_ERESTARTSYS or
288  * EINTR though.)
289  *
290  * block_signals() cannot be used for interruptible syscalls.
291  *
292  *
293  * How and why the safe_syscall implementation works:
294  *
295  * The basic setup is that we make the host syscall via a known
296  * section of host native assembly. If a signal occurs, our signal
297  * handler checks the interrupted host PC against the addresse of that
298  * known section. If the PC is before or at the address of the syscall
299  * instruction then we change the PC to point at a "return
300  * -TARGET_ERESTARTSYS" code path instead, and then exit the signal handler
301  * (causing the safe_syscall() call to immediately return that value).
302  * Then in the main.c loop if we see this magic return value we adjust
303  * the guest PC to wind it back to before the system call, and invoke
304  * the guest signal handler as usual.
305  *
306  * This winding-back will happen in two cases:
307  * (1) signal came in just before we took the host syscall (a race);
308  *   in this case we'll take the guest signal and have another go
309  *   at the syscall afterwards, and this is indistinguishable for the
310  *   guest from the timing having been different such that the guest
311  *   signal really did win the race
312  * (2) signal came in while the host syscall was blocking, and the
313  *   host kernel decided the syscall should be restarted;
314  *   in this case we want to restart the guest syscall also, and so
315  *   rewinding is the right thing. (Note that "restart" semantics mean
316  *   "first call the signal handler, then reattempt the syscall".)
317  * The other situation to consider is when a signal came in while the
318  * host syscall was blocking, and the host kernel decided that the syscall
319  * should not be restarted; in this case QEMU's host signal handler will
320  * be invoked with the PC pointing just after the syscall instruction,
321  * with registers indicating an EINTR return; the special code in the
322  * handler will not kick in, and we will return EINTR to the guest as
323  * we should.
324  *
325  * Notice that we can leave the host kernel to make the decision for
326  * us about whether to do a restart of the syscall or not; we do not
327  * need to check SA_RESTART flags in QEMU or distinguish the various
328  * kinds of restartability.
329  */
330 #ifdef HAVE_SAFE_SYSCALL
331 /* The core part of this function is implemented in assembly */
332 extern long safe_syscall_base(int *pending, long number, ...);
333 
334 #define safe_syscall(...)                                               \
335     ({                                                                  \
336         long ret_;                                                      \
337         int *psp_ = &((TaskState *)thread_cpu->opaque)->signal_pending; \
338         ret_ = safe_syscall_base(psp_, __VA_ARGS__);                    \
339         if (is_error(ret_)) {                                           \
340             errno = -ret_;                                              \
341             ret_ = -1;                                                  \
342         }                                                               \
343         ret_;                                                           \
344     })
345 
346 #else
347 
348 /* Fallback for architectures which don't yet provide a safe-syscall assembly
349  * fragment; note that this is racy!
350  * This should go away when all host architectures have been updated.
351  */
352 #define safe_syscall syscall
353 
354 #endif
355 
356 /* syscall.c */
357 int host_to_target_waitstatus(int status);
358 
359 /* strace.c */
360 void print_syscall(int num,
361                    abi_long arg1, abi_long arg2, abi_long arg3,
362                    abi_long arg4, abi_long arg5, abi_long arg6);
363 void print_syscall_ret(int num, abi_long arg1);
364 /**
365  * print_taken_signal:
366  * @target_signum: target signal being taken
367  * @tinfo: target_siginfo_t which will be passed to the guest for the signal
368  *
369  * Print strace output indicating that this signal is being taken by the guest,
370  * in a format similar to:
371  * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
372  */
373 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
374 extern int do_strace;
375 
376 /* signal.c */
377 void process_pending_signals(CPUArchState *cpu_env);
378 void signal_init(void);
379 int queue_signal(CPUArchState *env, int sig, int si_type,
380                  target_siginfo_t *info);
381 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
382 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
383 int target_to_host_signal(int sig);
384 int host_to_target_signal(int sig);
385 long do_sigreturn(CPUArchState *env);
386 long do_rt_sigreturn(CPUArchState *env);
387 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
388 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
389 /**
390  * block_signals: block all signals while handling this guest syscall
391  *
392  * Block all signals, and arrange that the signal mask is returned to
393  * its correct value for the guest before we resume execution of guest code.
394  * If this function returns non-zero, then the caller should immediately
395  * return -TARGET_ERESTARTSYS to the main loop, which will take the pending
396  * signal and restart execution of the syscall.
397  * If block_signals() returns zero, then the caller can continue with
398  * emulation of the system call knowing that no signals can be taken
399  * (and therefore that no race conditions will result).
400  * This should only be called once, because if it is called a second time
401  * it will always return non-zero. (Think of it like a mutex that can't
402  * be recursively locked.)
403  * Signals will be unblocked again by process_pending_signals().
404  *
405  * Return value: non-zero if there was a pending signal, zero if not.
406  */
407 int block_signals(void); /* Returns non zero if signal pending */
408 
409 #ifdef TARGET_I386
410 /* vm86.c */
411 void save_v86_state(CPUX86State *env);
412 void handle_vm86_trap(CPUX86State *env, int trapno);
413 void handle_vm86_fault(CPUX86State *env);
414 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
415 #elif defined(TARGET_SPARC64)
416 void sparc64_set_context(CPUSPARCState *env);
417 void sparc64_get_context(CPUSPARCState *env);
418 #endif
419 
420 /* mmap.c */
421 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
422 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
423                      int flags, int fd, abi_ulong offset);
424 int target_munmap(abi_ulong start, abi_ulong len);
425 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
426                        abi_ulong new_size, unsigned long flags,
427                        abi_ulong new_addr);
428 extern unsigned long last_brk;
429 extern abi_ulong mmap_next_start;
430 abi_ulong mmap_find_vma(abi_ulong, abi_ulong);
431 void mmap_fork_start(void);
432 void mmap_fork_end(int child);
433 
434 /* main.c */
435 extern unsigned long guest_stack_size;
436 
437 /* user access */
438 
439 #define VERIFY_READ 0
440 #define VERIFY_WRITE 1 /* implies read access */
441 
442 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
443 {
444     return page_check_range((target_ulong)addr, size,
445                             (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
446 }
447 
448 /* NOTE __get_user and __put_user use host pointers and don't check access.
449    These are usually used to access struct data members once the struct has
450    been locked - usually with lock_user_struct.  */
451 
452 /* Tricky points:
453    - Use __builtin_choose_expr to avoid type promotion from ?:,
454    - Invalid sizes result in a compile time error stemming from
455      the fact that abort has no parameters.
456    - It's easier to use the endian-specific unaligned load/store
457      functions than host-endian unaligned load/store plus tswapN.  */
458 
459 #define __put_user_e(x, hptr, e)                                        \
460   (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p,                   \
461    __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p,             \
462    __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p,             \
463    __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort))))   \
464      ((hptr), (x)), (void)0)
465 
466 #define __get_user_e(x, hptr, e)                                        \
467   ((x) = (typeof(*hptr))(                                               \
468    __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p,                  \
469    __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p,            \
470    __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p,             \
471    __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort))))   \
472      (hptr)), (void)0)
473 
474 #ifdef TARGET_WORDS_BIGENDIAN
475 # define __put_user(x, hptr)  __put_user_e(x, hptr, be)
476 # define __get_user(x, hptr)  __get_user_e(x, hptr, be)
477 #else
478 # define __put_user(x, hptr)  __put_user_e(x, hptr, le)
479 # define __get_user(x, hptr)  __get_user_e(x, hptr, le)
480 #endif
481 
482 /* put_user()/get_user() take a guest address and check access */
483 /* These are usually used to access an atomic data type, such as an int,
484  * that has been passed by address.  These internally perform locking
485  * and unlocking on the data type.
486  */
487 #define put_user(x, gaddr, target_type)					\
488 ({									\
489     abi_ulong __gaddr = (gaddr);					\
490     target_type *__hptr;						\
491     abi_long __ret = 0;							\
492     if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
493         __put_user((x), __hptr);				\
494         unlock_user(__hptr, __gaddr, sizeof(target_type));		\
495     } else								\
496         __ret = -TARGET_EFAULT;						\
497     __ret;								\
498 })
499 
500 #define get_user(x, gaddr, target_type)					\
501 ({									\
502     abi_ulong __gaddr = (gaddr);					\
503     target_type *__hptr;						\
504     abi_long __ret = 0;							\
505     if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
506         __get_user((x), __hptr);				\
507         unlock_user(__hptr, __gaddr, 0);				\
508     } else {								\
509         /* avoid warning */						\
510         (x) = 0;							\
511         __ret = -TARGET_EFAULT;						\
512     }									\
513     __ret;								\
514 })
515 
516 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
517 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
518 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
519 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
520 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
521 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
522 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
523 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
524 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
525 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
526 
527 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
528 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
529 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
530 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
531 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
532 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
533 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
534 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
535 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
536 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
537 
538 /* copy_from_user() and copy_to_user() are usually used to copy data
539  * buffers between the target and host.  These internally perform
540  * locking/unlocking of the memory.
541  */
542 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
543 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
544 
545 /* Functions for accessing guest memory.  The tget and tput functions
546    read/write single values, byteswapping as necessary.  The lock_user function
547    gets a pointer to a contiguous area of guest memory, but does not perform
548    any byteswapping.  lock_user may return either a pointer to the guest
549    memory, or a temporary buffer.  */
550 
551 /* Lock an area of guest memory into the host.  If copy is true then the
552    host area will have the same contents as the guest.  */
553 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
554 {
555     if (!access_ok(type, guest_addr, len))
556         return NULL;
557 #ifdef DEBUG_REMAP
558     {
559         void *addr;
560         addr = g_malloc(len);
561         if (copy)
562             memcpy(addr, g2h(guest_addr), len);
563         else
564             memset(addr, 0, len);
565         return addr;
566     }
567 #else
568     return g2h(guest_addr);
569 #endif
570 }
571 
572 /* Unlock an area of guest memory.  The first LEN bytes must be
573    flushed back to guest memory. host_ptr = NULL is explicitly
574    allowed and does nothing. */
575 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
576                                long len)
577 {
578 
579 #ifdef DEBUG_REMAP
580     if (!host_ptr)
581         return;
582     if (host_ptr == g2h(guest_addr))
583         return;
584     if (len > 0)
585         memcpy(g2h(guest_addr), host_ptr, len);
586     g_free(host_ptr);
587 #endif
588 }
589 
590 /* Return the length of a string in target memory or -TARGET_EFAULT if
591    access error. */
592 abi_long target_strlen(abi_ulong gaddr);
593 
594 /* Like lock_user but for null terminated strings.  */
595 static inline void *lock_user_string(abi_ulong guest_addr)
596 {
597     abi_long len;
598     len = target_strlen(guest_addr);
599     if (len < 0)
600         return NULL;
601     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
602 }
603 
604 /* Helper macros for locking/unlocking a target struct.  */
605 #define lock_user_struct(type, host_ptr, guest_addr, copy)	\
606     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
607 #define unlock_user_struct(host_ptr, guest_addr, copy)		\
608     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
609 
610 #include <pthread.h>
611 
612 /* Include target-specific struct and function definitions;
613  * they may need access to the target-independent structures
614  * above, so include them last.
615  */
616 #include "target_cpu.h"
617 #include "target_signal.h"
618 #include "target_structs.h"
619 
620 #endif /* QEMU_H */
621