xref: /openbmc/qemu/linux-user/qemu.h (revision e09484ef)
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 is the size of the host kernel's sigset_t, needed where we make
24  * direct system calls that take a sigset_t pointer and a size.
25  */
26 #define SIGSET_T_SIZE (_NSIG / 8)
27 
28 /* This struct is used to hold certain information about the image.
29  * Basically, it replicates in user space what would be certain
30  * task_struct fields in the kernel
31  */
32 struct image_info {
33         abi_ulong       load_bias;
34         abi_ulong       load_addr;
35         abi_ulong       start_code;
36         abi_ulong       end_code;
37         abi_ulong       start_data;
38         abi_ulong       end_data;
39         abi_ulong       start_brk;
40         abi_ulong       brk;
41         abi_ulong       start_mmap;
42         abi_ulong       start_stack;
43         abi_ulong       stack_limit;
44         abi_ulong       entry;
45         abi_ulong       code_offset;
46         abi_ulong       data_offset;
47         abi_ulong       saved_auxv;
48         abi_ulong       auxv_len;
49         abi_ulong       arg_start;
50         abi_ulong       arg_end;
51         uint32_t        elf_flags;
52 	int		personality;
53 #ifdef CONFIG_USE_FDPIC
54         abi_ulong       loadmap_addr;
55         uint16_t        nsegs;
56         void           *loadsegs;
57         abi_ulong       pt_dynamic_addr;
58         struct image_info *other_info;
59 #endif
60 };
61 
62 #ifdef TARGET_I386
63 /* Information about the current linux thread */
64 struct vm86_saved_state {
65     uint32_t eax; /* return code */
66     uint32_t ebx;
67     uint32_t ecx;
68     uint32_t edx;
69     uint32_t esi;
70     uint32_t edi;
71     uint32_t ebp;
72     uint32_t esp;
73     uint32_t eflags;
74     uint32_t eip;
75     uint16_t cs, ss, ds, es, fs, gs;
76 };
77 #endif
78 
79 #if defined(TARGET_ARM) && defined(TARGET_ABI32)
80 /* FPU emulator */
81 #include "nwfpe/fpa11.h"
82 #endif
83 
84 #define MAX_SIGQUEUE_SIZE 1024
85 
86 struct emulated_sigtable {
87     int pending; /* true if signal is pending */
88     target_siginfo_t info;
89 };
90 
91 /* NOTE: we force a big alignment so that the stack stored after is
92    aligned too */
93 typedef struct TaskState {
94     pid_t ts_tid;     /* tid (or pid) of this task */
95 #ifdef TARGET_ARM
96 # ifdef TARGET_ABI32
97     /* FPA state */
98     FPA11 fpa;
99 # endif
100     int swi_errno;
101 #endif
102 #ifdef TARGET_UNICORE32
103     int swi_errno;
104 #endif
105 #if defined(TARGET_I386) && !defined(TARGET_X86_64)
106     abi_ulong target_v86;
107     struct vm86_saved_state vm86_saved_regs;
108     struct target_vm86plus_struct vm86plus;
109     uint32_t v86flags;
110     uint32_t v86mask;
111 #endif
112     abi_ulong child_tidptr;
113 #ifdef TARGET_M68K
114     int sim_syscalls;
115     abi_ulong tp_value;
116 #endif
117 #if defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_UNICORE32)
118     /* Extra fields for semihosted binaries.  */
119     abi_ulong heap_base;
120     abi_ulong heap_limit;
121 #endif
122     abi_ulong stack_base;
123     int used; /* non zero if used */
124     struct image_info *info;
125     struct linux_binprm *bprm;
126 
127     struct emulated_sigtable sync_signal;
128     struct emulated_sigtable sigtab[TARGET_NSIG];
129     /* This thread's signal mask, as requested by the guest program.
130      * The actual signal mask of this thread may differ:
131      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
132      *  + sometimes we block all signals to avoid races
133      */
134     sigset_t signal_mask;
135     /* The signal mask imposed by a guest sigsuspend syscall, if we are
136      * currently in the middle of such a syscall
137      */
138     sigset_t sigsuspend_mask;
139     /* Nonzero if we're leaving a sigsuspend and sigsuspend_mask is valid. */
140     int in_sigsuspend;
141 
142     /* Nonzero if process_pending_signals() needs to do something (either
143      * handle a pending signal or unblock signals).
144      * This flag is written from a signal handler so should be accessed via
145      * the atomic_read() and atomic_write() functions. (It is not accessed
146      * from multiple threads.)
147      */
148     int signal_pending;
149 
150 } __attribute__((aligned(16))) TaskState;
151 
152 extern char *exec_path;
153 void init_task_state(TaskState *ts);
154 void task_settid(TaskState *);
155 void stop_all_tasks(void);
156 extern const char *qemu_uname_release;
157 extern unsigned long mmap_min_addr;
158 
159 /* ??? See if we can avoid exposing so much of the loader internals.  */
160 
161 /* Read a good amount of data initially, to hopefully get all the
162    program headers loaded.  */
163 #define BPRM_BUF_SIZE  1024
164 
165 /*
166  * This structure is used to hold the arguments that are
167  * used when loading binaries.
168  */
169 struct linux_binprm {
170         char buf[BPRM_BUF_SIZE] __attribute__((aligned));
171         abi_ulong p;
172 	int fd;
173         int e_uid, e_gid;
174         int argc, envc;
175         char **argv;
176         char **envp;
177         char * filename;        /* Name of binary */
178         int (*core_dump)(int, const CPUArchState *); /* coredump routine */
179 };
180 
181 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
182 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
183                               abi_ulong stringp, int push_ptr);
184 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
185              struct target_pt_regs * regs, struct image_info *infop,
186              struct linux_binprm *);
187 
188 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
189 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
190 
191 abi_long memcpy_to_target(abi_ulong dest, const void *src,
192                           unsigned long len);
193 void target_set_brk(abi_ulong new_brk);
194 abi_long do_brk(abi_ulong new_brk);
195 void syscall_init(void);
196 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
197                     abi_long arg2, abi_long arg3, abi_long arg4,
198                     abi_long arg5, abi_long arg6, abi_long arg7,
199                     abi_long arg8);
200 void gemu_log(const char *fmt, ...) GCC_FMT_ATTR(1, 2);
201 extern THREAD CPUState *thread_cpu;
202 void cpu_loop(CPUArchState *env);
203 const char *target_strerror(int err);
204 int get_osversion(void);
205 void init_qemu_uname_release(void);
206 void fork_start(void);
207 void fork_end(int child);
208 
209 /* Creates the initial guest address space in the host memory space using
210  * the given host start address hint and size.  The guest_start parameter
211  * specifies the start address of the guest space.  guest_base will be the
212  * difference between the host start address computed by this function and
213  * guest_start.  If fixed is specified, then the mapped address space must
214  * start at host_start.  The real start address of the mapped memory space is
215  * returned or -1 if there was an error.
216  */
217 unsigned long init_guest_space(unsigned long host_start,
218                                unsigned long host_size,
219                                unsigned long guest_start,
220                                bool fixed);
221 
222 #include "qemu/log.h"
223 
224 /* safe_syscall.S */
225 
226 /**
227  * safe_syscall:
228  * @int number: number of system call to make
229  * ...: arguments to the system call
230  *
231  * Call a system call if guest signal not pending.
232  * This has the same API as the libc syscall() function, except that it
233  * may return -1 with errno == TARGET_ERESTARTSYS if a signal was pending.
234  *
235  * Returns: the system call result, or -1 with an error code in errno
236  * (Errnos are host errnos; we rely on TARGET_ERESTARTSYS not clashing
237  * with any of the host errno values.)
238  */
239 
240 /* A guide to using safe_syscall() to handle interactions between guest
241  * syscalls and guest signals:
242  *
243  * Guest syscalls come in two flavours:
244  *
245  * (1) Non-interruptible syscalls
246  *
247  * These are guest syscalls that never get interrupted by signals and
248  * so never return EINTR. They can be implemented straightforwardly in
249  * QEMU: just make sure that if the implementation code has to make any
250  * blocking calls that those calls are retried if they return EINTR.
251  * It's also OK to implement these with safe_syscall, though it will be
252  * a little less efficient if a signal is delivered at the 'wrong' moment.
253  *
254  * Some non-interruptible syscalls need to be handled using block_signals()
255  * to block signals for the duration of the syscall. This mainly applies
256  * to code which needs to modify the data structures used by the
257  * host_signal_handler() function and the functions it calls, including
258  * all syscalls which change the thread's signal mask.
259  *
260  * (2) Interruptible syscalls
261  *
262  * These are guest syscalls that can be interrupted by signals and
263  * for which we need to either return EINTR or arrange for the guest
264  * syscall to be restarted. This category includes both syscalls which
265  * always restart (and in the kernel return -ERESTARTNOINTR), ones
266  * which only restart if there is no handler (kernel returns -ERESTARTNOHAND
267  * or -ERESTART_RESTARTBLOCK), and the most common kind which restart
268  * if the handler was registered with SA_RESTART (kernel returns
269  * -ERESTARTSYS). System calls which are only interruptible in some
270  * situations (like 'open') also need to be handled this way.
271  *
272  * Here it is important that the host syscall is made
273  * via this safe_syscall() function, and *not* via the host libc.
274  * If the host libc is used then the implementation will appear to work
275  * most of the time, but there will be a race condition where a
276  * signal could arrive just before we make the host syscall inside libc,
277  * and then then guest syscall will not correctly be interrupted.
278  * Instead the implementation of the guest syscall can use the safe_syscall
279  * function but otherwise just return the result or errno in the usual
280  * way; the main loop code will take care of restarting the syscall
281  * if appropriate.
282  *
283  * (If the implementation needs to make multiple host syscalls this is
284  * OK; any which might really block must be via safe_syscall(); for those
285  * which are only technically blocking (ie which we know in practice won't
286  * stay in the host kernel indefinitely) it's OK to use libc if necessary.
287  * You must be able to cope with backing out correctly if some safe_syscall
288  * you make in the implementation returns either -TARGET_ERESTARTSYS or
289  * EINTR though.)
290  *
291  * block_signals() cannot be used for interruptible syscalls.
292  *
293  *
294  * How and why the safe_syscall implementation works:
295  *
296  * The basic setup is that we make the host syscall via a known
297  * section of host native assembly. If a signal occurs, our signal
298  * handler checks the interrupted host PC against the addresse of that
299  * known section. If the PC is before or at the address of the syscall
300  * instruction then we change the PC to point at a "return
301  * -TARGET_ERESTARTSYS" code path instead, and then exit the signal handler
302  * (causing the safe_syscall() call to immediately return that value).
303  * Then in the main.c loop if we see this magic return value we adjust
304  * the guest PC to wind it back to before the system call, and invoke
305  * the guest signal handler as usual.
306  *
307  * This winding-back will happen in two cases:
308  * (1) signal came in just before we took the host syscall (a race);
309  *   in this case we'll take the guest signal and have another go
310  *   at the syscall afterwards, and this is indistinguishable for the
311  *   guest from the timing having been different such that the guest
312  *   signal really did win the race
313  * (2) signal came in while the host syscall was blocking, and the
314  *   host kernel decided the syscall should be restarted;
315  *   in this case we want to restart the guest syscall also, and so
316  *   rewinding is the right thing. (Note that "restart" semantics mean
317  *   "first call the signal handler, then reattempt the syscall".)
318  * The other situation to consider is when a signal came in while the
319  * host syscall was blocking, and the host kernel decided that the syscall
320  * should not be restarted; in this case QEMU's host signal handler will
321  * be invoked with the PC pointing just after the syscall instruction,
322  * with registers indicating an EINTR return; the special code in the
323  * handler will not kick in, and we will return EINTR to the guest as
324  * we should.
325  *
326  * Notice that we can leave the host kernel to make the decision for
327  * us about whether to do a restart of the syscall or not; we do not
328  * need to check SA_RESTART flags in QEMU or distinguish the various
329  * kinds of restartability.
330  */
331 #ifdef HAVE_SAFE_SYSCALL
332 /* The core part of this function is implemented in assembly */
333 extern long safe_syscall_base(int *pending, long number, ...);
334 
335 #define safe_syscall(...)                                               \
336     ({                                                                  \
337         long ret_;                                                      \
338         int *psp_ = &((TaskState *)thread_cpu->opaque)->signal_pending; \
339         ret_ = safe_syscall_base(psp_, __VA_ARGS__);                    \
340         if (is_error(ret_)) {                                           \
341             errno = -ret_;                                              \
342             ret_ = -1;                                                  \
343         }                                                               \
344         ret_;                                                           \
345     })
346 
347 #else
348 
349 /* Fallback for architectures which don't yet provide a safe-syscall assembly
350  * fragment; note that this is racy!
351  * This should go away when all host architectures have been updated.
352  */
353 #define safe_syscall syscall
354 
355 #endif
356 
357 /* syscall.c */
358 int host_to_target_waitstatus(int status);
359 
360 /* strace.c */
361 void print_syscall(int num,
362                    abi_long arg1, abi_long arg2, abi_long arg3,
363                    abi_long arg4, abi_long arg5, abi_long arg6);
364 void print_syscall_ret(int num, abi_long arg1);
365 extern int do_strace;
366 
367 /* signal.c */
368 void process_pending_signals(CPUArchState *cpu_env);
369 void signal_init(void);
370 int queue_signal(CPUArchState *env, int sig, target_siginfo_t *info);
371 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
372 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
373 int target_to_host_signal(int sig);
374 int host_to_target_signal(int sig);
375 long do_sigreturn(CPUArchState *env);
376 long do_rt_sigreturn(CPUArchState *env);
377 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
378 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
379 /**
380  * block_signals: block all signals while handling this guest syscall
381  *
382  * Block all signals, and arrange that the signal mask is returned to
383  * its correct value for the guest before we resume execution of guest code.
384  * If this function returns non-zero, then the caller should immediately
385  * return -TARGET_ERESTARTSYS to the main loop, which will take the pending
386  * signal and restart execution of the syscall.
387  * If block_signals() returns zero, then the caller can continue with
388  * emulation of the system call knowing that no signals can be taken
389  * (and therefore that no race conditions will result).
390  * This should only be called once, because if it is called a second time
391  * it will always return non-zero. (Think of it like a mutex that can't
392  * be recursively locked.)
393  * Signals will be unblocked again by process_pending_signals().
394  *
395  * Return value: non-zero if there was a pending signal, zero if not.
396  */
397 int block_signals(void); /* Returns non zero if signal pending */
398 
399 #ifdef TARGET_I386
400 /* vm86.c */
401 void save_v86_state(CPUX86State *env);
402 void handle_vm86_trap(CPUX86State *env, int trapno);
403 void handle_vm86_fault(CPUX86State *env);
404 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
405 #elif defined(TARGET_SPARC64)
406 void sparc64_set_context(CPUSPARCState *env);
407 void sparc64_get_context(CPUSPARCState *env);
408 #endif
409 
410 /* mmap.c */
411 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
412 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
413                      int flags, int fd, abi_ulong offset);
414 int target_munmap(abi_ulong start, abi_ulong len);
415 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
416                        abi_ulong new_size, unsigned long flags,
417                        abi_ulong new_addr);
418 int target_msync(abi_ulong start, abi_ulong len, int flags);
419 extern unsigned long last_brk;
420 extern abi_ulong mmap_next_start;
421 abi_ulong mmap_find_vma(abi_ulong, abi_ulong);
422 void mmap_fork_start(void);
423 void mmap_fork_end(int child);
424 
425 /* main.c */
426 extern unsigned long guest_stack_size;
427 
428 /* user access */
429 
430 #define VERIFY_READ 0
431 #define VERIFY_WRITE 1 /* implies read access */
432 
433 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
434 {
435     return page_check_range((target_ulong)addr, size,
436                             (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
437 }
438 
439 /* NOTE __get_user and __put_user use host pointers and don't check access.
440    These are usually used to access struct data members once the struct has
441    been locked - usually with lock_user_struct.  */
442 
443 /* Tricky points:
444    - Use __builtin_choose_expr to avoid type promotion from ?:,
445    - Invalid sizes result in a compile time error stemming from
446      the fact that abort has no parameters.
447    - It's easier to use the endian-specific unaligned load/store
448      functions than host-endian unaligned load/store plus tswapN.  */
449 
450 #define __put_user_e(x, hptr, e)                                        \
451   (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p,                   \
452    __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p,             \
453    __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p,             \
454    __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort))))   \
455      ((hptr), (x)), (void)0)
456 
457 #define __get_user_e(x, hptr, e)                                        \
458   ((x) = (typeof(*hptr))(                                               \
459    __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p,                  \
460    __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p,            \
461    __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p,             \
462    __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort))))   \
463      (hptr)), (void)0)
464 
465 #ifdef TARGET_WORDS_BIGENDIAN
466 # define __put_user(x, hptr)  __put_user_e(x, hptr, be)
467 # define __get_user(x, hptr)  __get_user_e(x, hptr, be)
468 #else
469 # define __put_user(x, hptr)  __put_user_e(x, hptr, le)
470 # define __get_user(x, hptr)  __get_user_e(x, hptr, le)
471 #endif
472 
473 /* put_user()/get_user() take a guest address and check access */
474 /* These are usually used to access an atomic data type, such as an int,
475  * that has been passed by address.  These internally perform locking
476  * and unlocking on the data type.
477  */
478 #define put_user(x, gaddr, target_type)					\
479 ({									\
480     abi_ulong __gaddr = (gaddr);					\
481     target_type *__hptr;						\
482     abi_long __ret = 0;							\
483     if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
484         __put_user((x), __hptr);				\
485         unlock_user(__hptr, __gaddr, sizeof(target_type));		\
486     } else								\
487         __ret = -TARGET_EFAULT;						\
488     __ret;								\
489 })
490 
491 #define get_user(x, gaddr, target_type)					\
492 ({									\
493     abi_ulong __gaddr = (gaddr);					\
494     target_type *__hptr;						\
495     abi_long __ret = 0;							\
496     if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
497         __get_user((x), __hptr);				\
498         unlock_user(__hptr, __gaddr, 0);				\
499     } else {								\
500         /* avoid warning */						\
501         (x) = 0;							\
502         __ret = -TARGET_EFAULT;						\
503     }									\
504     __ret;								\
505 })
506 
507 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
508 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
509 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
510 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
511 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
512 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
513 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
514 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
515 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
516 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
517 
518 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
519 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
520 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
521 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
522 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
523 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
524 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
525 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
526 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
527 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
528 
529 /* copy_from_user() and copy_to_user() are usually used to copy data
530  * buffers between the target and host.  These internally perform
531  * locking/unlocking of the memory.
532  */
533 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
534 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
535 
536 /* Functions for accessing guest memory.  The tget and tput functions
537    read/write single values, byteswapping as necessary.  The lock_user function
538    gets a pointer to a contiguous area of guest memory, but does not perform
539    any byteswapping.  lock_user may return either a pointer to the guest
540    memory, or a temporary buffer.  */
541 
542 /* Lock an area of guest memory into the host.  If copy is true then the
543    host area will have the same contents as the guest.  */
544 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
545 {
546     if (!access_ok(type, guest_addr, len))
547         return NULL;
548 #ifdef DEBUG_REMAP
549     {
550         void *addr;
551         addr = malloc(len);
552         if (copy)
553             memcpy(addr, g2h(guest_addr), len);
554         else
555             memset(addr, 0, len);
556         return addr;
557     }
558 #else
559     return g2h(guest_addr);
560 #endif
561 }
562 
563 /* Unlock an area of guest memory.  The first LEN bytes must be
564    flushed back to guest memory. host_ptr = NULL is explicitly
565    allowed and does nothing. */
566 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
567                                long len)
568 {
569 
570 #ifdef DEBUG_REMAP
571     if (!host_ptr)
572         return;
573     if (host_ptr == g2h(guest_addr))
574         return;
575     if (len > 0)
576         memcpy(g2h(guest_addr), host_ptr, len);
577     free(host_ptr);
578 #endif
579 }
580 
581 /* Return the length of a string in target memory or -TARGET_EFAULT if
582    access error. */
583 abi_long target_strlen(abi_ulong gaddr);
584 
585 /* Like lock_user but for null terminated strings.  */
586 static inline void *lock_user_string(abi_ulong guest_addr)
587 {
588     abi_long len;
589     len = target_strlen(guest_addr);
590     if (len < 0)
591         return NULL;
592     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
593 }
594 
595 /* Helper macros for locking/unlocking a target struct.  */
596 #define lock_user_struct(type, host_ptr, guest_addr, copy)	\
597     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
598 #define unlock_user_struct(host_ptr, guest_addr, copy)		\
599     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
600 
601 #include <pthread.h>
602 
603 /* Include target-specific struct and function definitions;
604  * they may need access to the target-independent structures
605  * above, so include them last.
606  */
607 #include "target_cpu.h"
608 #include "target_signal.h"
609 #include "target_structs.h"
610 
611 #endif /* QEMU_H */
612