xref: /openbmc/qemu/linux-user/qemu.h (revision 7d8cbbab)
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 
20 /* This is the size of the host kernel's sigset_t, needed where we make
21  * direct system calls that take a sigset_t pointer and a size.
22  */
23 #define SIGSET_T_SIZE (_NSIG / 8)
24 
25 /* This struct is used to hold certain information about the image.
26  * Basically, it replicates in user space what would be certain
27  * task_struct fields in the kernel
28  */
29 struct image_info {
30         abi_ulong       load_bias;
31         abi_ulong       load_addr;
32         abi_ulong       start_code;
33         abi_ulong       end_code;
34         abi_ulong       start_data;
35         abi_ulong       end_data;
36         abi_ulong       start_brk;
37         abi_ulong       brk;
38         abi_ulong       reserve_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     abi_ulong tp_value;
120 #endif
121 #if defined(TARGET_ARM) || defined(TARGET_M68K)
122     /* Extra fields for semihosted binaries.  */
123     abi_ulong heap_base;
124     abi_ulong heap_limit;
125 #endif
126     abi_ulong stack_base;
127     int used; /* non zero if used */
128     struct image_info *info;
129     struct linux_binprm *bprm;
130 
131     struct emulated_sigtable sync_signal;
132     struct emulated_sigtable sigtab[TARGET_NSIG];
133     /* This thread's signal mask, as requested by the guest program.
134      * The actual signal mask of this thread may differ:
135      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
136      *  + sometimes we block all signals to avoid races
137      */
138     sigset_t signal_mask;
139     /* The signal mask imposed by a guest sigsuspend syscall, if we are
140      * currently in the middle of such a syscall
141      */
142     sigset_t sigsuspend_mask;
143     /* Nonzero if we're leaving a sigsuspend and sigsuspend_mask is valid. */
144     int in_sigsuspend;
145 
146     /* Nonzero if process_pending_signals() needs to do something (either
147      * handle a pending signal or unblock signals).
148      * This flag is written from a signal handler so should be accessed via
149      * the atomic_read() and atomic_set() functions. (It is not accessed
150      * from multiple threads.)
151      */
152     int signal_pending;
153 
154     /* This thread's sigaltstack, if it has one */
155     struct target_sigaltstack sigaltstack_used;
156 } __attribute__((aligned(16))) TaskState;
157 
158 extern char *exec_path;
159 void init_task_state(TaskState *ts);
160 void task_settid(TaskState *);
161 void stop_all_tasks(void);
162 extern const char *qemu_uname_release;
163 extern unsigned long mmap_min_addr;
164 
165 /* ??? See if we can avoid exposing so much of the loader internals.  */
166 
167 /* Read a good amount of data initially, to hopefully get all the
168    program headers loaded.  */
169 #define BPRM_BUF_SIZE  1024
170 
171 /*
172  * This structure is used to hold the arguments that are
173  * used when loading binaries.
174  */
175 struct linux_binprm {
176         char buf[BPRM_BUF_SIZE] __attribute__((aligned));
177         abi_ulong p;
178         int fd;
179         int e_uid, e_gid;
180         int argc, envc;
181         char **argv;
182         char **envp;
183         char * filename;        /* Name of binary */
184         int (*core_dump)(int, const CPUArchState *); /* coredump routine */
185 };
186 
187 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
188 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
189                               abi_ulong stringp, int push_ptr);
190 int loader_exec(int fdexec, const char *filename, char **argv, char **envp,
191              struct target_pt_regs * regs, struct image_info *infop,
192              struct linux_binprm *);
193 
194 /* Returns true if the image uses the FDPIC ABI. If this is the case,
195  * we have to provide some information (loadmap, pt_dynamic_info) such
196  * that the program can be relocated adequately. This is also useful
197  * when handling signals.
198  */
199 int info_is_fdpic(struct image_info *info);
200 
201 uint32_t get_elf_eflags(int fd);
202 int load_elf_binary(struct linux_binprm *bprm, struct image_info *info);
203 int load_flt_binary(struct linux_binprm *bprm, struct image_info *info);
204 
205 abi_long memcpy_to_target(abi_ulong dest, const void *src,
206                           unsigned long len);
207 void target_set_brk(abi_ulong new_brk);
208 abi_long do_brk(abi_ulong new_brk);
209 void syscall_init(void);
210 abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
211                     abi_long arg2, abi_long arg3, abi_long arg4,
212                     abi_long arg5, abi_long arg6, abi_long arg7,
213                     abi_long arg8);
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 /**
223  * probe_guest_base:
224  * @image_name: the executable being loaded
225  * @loaddr: the lowest fixed address in the executable
226  * @hiaddr: the highest fixed address in the executable
227  *
228  * Creates the initial guest address space in the host memory space.
229  *
230  * If @loaddr == 0, then no address in the executable is fixed,
231  * i.e. it is fully relocatable.  In that case @hiaddr is the size
232  * of the executable.
233  *
234  * This function will not return if a valid value for guest_base
235  * cannot be chosen.  On return, the executable loader can expect
236  *
237  *    target_mmap(loaddr, hiaddr - loaddr, ...)
238  *
239  * to succeed.
240  */
241 void probe_guest_base(const char *image_name,
242                       abi_ulong loaddr, abi_ulong hiaddr);
243 
244 #include "qemu/log.h"
245 
246 /* safe_syscall.S */
247 
248 /**
249  * safe_syscall:
250  * @int number: number of system call to make
251  * ...: arguments to the system call
252  *
253  * Call a system call if guest signal not pending.
254  * This has the same API as the libc syscall() function, except that it
255  * may return -1 with errno == TARGET_ERESTARTSYS if a signal was pending.
256  *
257  * Returns: the system call result, or -1 with an error code in errno
258  * (Errnos are host errnos; we rely on TARGET_ERESTARTSYS not clashing
259  * with any of the host errno values.)
260  */
261 
262 /* A guide to using safe_syscall() to handle interactions between guest
263  * syscalls and guest signals:
264  *
265  * Guest syscalls come in two flavours:
266  *
267  * (1) Non-interruptible syscalls
268  *
269  * These are guest syscalls that never get interrupted by signals and
270  * so never return EINTR. They can be implemented straightforwardly in
271  * QEMU: just make sure that if the implementation code has to make any
272  * blocking calls that those calls are retried if they return EINTR.
273  * It's also OK to implement these with safe_syscall, though it will be
274  * a little less efficient if a signal is delivered at the 'wrong' moment.
275  *
276  * Some non-interruptible syscalls need to be handled using block_signals()
277  * to block signals for the duration of the syscall. This mainly applies
278  * to code which needs to modify the data structures used by the
279  * host_signal_handler() function and the functions it calls, including
280  * all syscalls which change the thread's signal mask.
281  *
282  * (2) Interruptible syscalls
283  *
284  * These are guest syscalls that can be interrupted by signals and
285  * for which we need to either return EINTR or arrange for the guest
286  * syscall to be restarted. This category includes both syscalls which
287  * always restart (and in the kernel return -ERESTARTNOINTR), ones
288  * which only restart if there is no handler (kernel returns -ERESTARTNOHAND
289  * or -ERESTART_RESTARTBLOCK), and the most common kind which restart
290  * if the handler was registered with SA_RESTART (kernel returns
291  * -ERESTARTSYS). System calls which are only interruptible in some
292  * situations (like 'open') also need to be handled this way.
293  *
294  * Here it is important that the host syscall is made
295  * via this safe_syscall() function, and *not* via the host libc.
296  * If the host libc is used then the implementation will appear to work
297  * most of the time, but there will be a race condition where a
298  * signal could arrive just before we make the host syscall inside libc,
299  * and then then guest syscall will not correctly be interrupted.
300  * Instead the implementation of the guest syscall can use the safe_syscall
301  * function but otherwise just return the result or errno in the usual
302  * way; the main loop code will take care of restarting the syscall
303  * if appropriate.
304  *
305  * (If the implementation needs to make multiple host syscalls this is
306  * OK; any which might really block must be via safe_syscall(); for those
307  * which are only technically blocking (ie which we know in practice won't
308  * stay in the host kernel indefinitely) it's OK to use libc if necessary.
309  * You must be able to cope with backing out correctly if some safe_syscall
310  * you make in the implementation returns either -TARGET_ERESTARTSYS or
311  * EINTR though.)
312  *
313  * block_signals() cannot be used for interruptible syscalls.
314  *
315  *
316  * How and why the safe_syscall implementation works:
317  *
318  * The basic setup is that we make the host syscall via a known
319  * section of host native assembly. If a signal occurs, our signal
320  * handler checks the interrupted host PC against the addresse of that
321  * known section. If the PC is before or at the address of the syscall
322  * instruction then we change the PC to point at a "return
323  * -TARGET_ERESTARTSYS" code path instead, and then exit the signal handler
324  * (causing the safe_syscall() call to immediately return that value).
325  * Then in the main.c loop if we see this magic return value we adjust
326  * the guest PC to wind it back to before the system call, and invoke
327  * the guest signal handler as usual.
328  *
329  * This winding-back will happen in two cases:
330  * (1) signal came in just before we took the host syscall (a race);
331  *   in this case we'll take the guest signal and have another go
332  *   at the syscall afterwards, and this is indistinguishable for the
333  *   guest from the timing having been different such that the guest
334  *   signal really did win the race
335  * (2) signal came in while the host syscall was blocking, and the
336  *   host kernel decided the syscall should be restarted;
337  *   in this case we want to restart the guest syscall also, and so
338  *   rewinding is the right thing. (Note that "restart" semantics mean
339  *   "first call the signal handler, then reattempt the syscall".)
340  * The other situation to consider is when a signal came in while the
341  * host syscall was blocking, and the host kernel decided that the syscall
342  * should not be restarted; in this case QEMU's host signal handler will
343  * be invoked with the PC pointing just after the syscall instruction,
344  * with registers indicating an EINTR return; the special code in the
345  * handler will not kick in, and we will return EINTR to the guest as
346  * we should.
347  *
348  * Notice that we can leave the host kernel to make the decision for
349  * us about whether to do a restart of the syscall or not; we do not
350  * need to check SA_RESTART flags in QEMU or distinguish the various
351  * kinds of restartability.
352  */
353 #ifdef HAVE_SAFE_SYSCALL
354 /* The core part of this function is implemented in assembly */
355 extern long safe_syscall_base(int *pending, long number, ...);
356 
357 #define safe_syscall(...)                                               \
358     ({                                                                  \
359         long ret_;                                                      \
360         int *psp_ = &((TaskState *)thread_cpu->opaque)->signal_pending; \
361         ret_ = safe_syscall_base(psp_, __VA_ARGS__);                    \
362         if (is_error(ret_)) {                                           \
363             errno = -ret_;                                              \
364             ret_ = -1;                                                  \
365         }                                                               \
366         ret_;                                                           \
367     })
368 
369 #else
370 
371 /* Fallback for architectures which don't yet provide a safe-syscall assembly
372  * fragment; note that this is racy!
373  * This should go away when all host architectures have been updated.
374  */
375 #define safe_syscall syscall
376 
377 #endif
378 
379 /* syscall.c */
380 int host_to_target_waitstatus(int status);
381 
382 /* strace.c */
383 void print_syscall(int num,
384                    abi_long arg1, abi_long arg2, abi_long arg3,
385                    abi_long arg4, abi_long arg5, abi_long arg6);
386 void print_syscall_ret(int num, abi_long arg1);
387 /**
388  * print_taken_signal:
389  * @target_signum: target signal being taken
390  * @tinfo: target_siginfo_t which will be passed to the guest for the signal
391  *
392  * Print strace output indicating that this signal is being taken by the guest,
393  * in a format similar to:
394  * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
395  */
396 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
397 
398 /* signal.c */
399 void process_pending_signals(CPUArchState *cpu_env);
400 void signal_init(void);
401 int queue_signal(CPUArchState *env, int sig, int si_type,
402                  target_siginfo_t *info);
403 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info);
404 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo);
405 int target_to_host_signal(int sig);
406 int host_to_target_signal(int sig);
407 long do_sigreturn(CPUArchState *env);
408 long do_rt_sigreturn(CPUArchState *env);
409 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
410 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
411 abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx,
412                         abi_ulong unew_ctx, abi_long ctx_size);
413 /**
414  * block_signals: block all signals while handling this guest syscall
415  *
416  * Block all signals, and arrange that the signal mask is returned to
417  * its correct value for the guest before we resume execution of guest code.
418  * If this function returns non-zero, then the caller should immediately
419  * return -TARGET_ERESTARTSYS to the main loop, which will take the pending
420  * signal and restart execution of the syscall.
421  * If block_signals() returns zero, then the caller can continue with
422  * emulation of the system call knowing that no signals can be taken
423  * (and therefore that no race conditions will result).
424  * This should only be called once, because if it is called a second time
425  * it will always return non-zero. (Think of it like a mutex that can't
426  * be recursively locked.)
427  * Signals will be unblocked again by process_pending_signals().
428  *
429  * Return value: non-zero if there was a pending signal, zero if not.
430  */
431 int block_signals(void); /* Returns non zero if signal pending */
432 
433 #ifdef TARGET_I386
434 /* vm86.c */
435 void save_v86_state(CPUX86State *env);
436 void handle_vm86_trap(CPUX86State *env, int trapno);
437 void handle_vm86_fault(CPUX86State *env);
438 int do_vm86(CPUX86State *env, long subfunction, abi_ulong v86_addr);
439 #elif defined(TARGET_SPARC64)
440 void sparc64_set_context(CPUSPARCState *env);
441 void sparc64_get_context(CPUSPARCState *env);
442 #endif
443 
444 /* mmap.c */
445 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
446 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
447                      int flags, int fd, abi_ulong offset);
448 int target_munmap(abi_ulong start, abi_ulong len);
449 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
450                        abi_ulong new_size, unsigned long flags,
451                        abi_ulong new_addr);
452 extern unsigned long last_brk;
453 extern abi_ulong mmap_next_start;
454 abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong);
455 void mmap_fork_start(void);
456 void mmap_fork_end(int child);
457 
458 /* main.c */
459 extern unsigned long guest_stack_size;
460 
461 /* user access */
462 
463 #define VERIFY_READ 0
464 #define VERIFY_WRITE 1 /* implies read access */
465 
466 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
467 {
468     return guest_addr_valid(addr) &&
469            (size == 0 || guest_addr_valid(addr + size - 1)) &&
470            page_check_range((target_ulong)addr, size,
471                             (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
472 }
473 
474 /* NOTE __get_user and __put_user use host pointers and don't check access.
475    These are usually used to access struct data members once the struct has
476    been locked - usually with lock_user_struct.  */
477 
478 /*
479  * Tricky points:
480  * - Use __builtin_choose_expr to avoid type promotion from ?:,
481  * - Invalid sizes result in a compile time error stemming from
482  *   the fact that abort has no parameters.
483  * - It's easier to use the endian-specific unaligned load/store
484  *   functions than host-endian unaligned load/store plus tswapN.
485  * - The pragmas are necessary only to silence a clang false-positive
486  *   warning: see https://bugs.llvm.org/show_bug.cgi?id=39113 .
487  * - gcc has bugs in its _Pragma() support in some versions, eg
488  *   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83256 -- so we only
489  *   include the warning-suppression pragmas for clang
490  */
491 #if defined(__clang__) && __has_warning("-Waddress-of-packed-member")
492 #define PRAGMA_DISABLE_PACKED_WARNING                                   \
493     _Pragma("GCC diagnostic push");                                     \
494     _Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"")
495 
496 #define PRAGMA_REENABLE_PACKED_WARNING          \
497     _Pragma("GCC diagnostic pop")
498 
499 #else
500 #define PRAGMA_DISABLE_PACKED_WARNING
501 #define PRAGMA_REENABLE_PACKED_WARNING
502 #endif
503 
504 #define __put_user_e(x, hptr, e)                                            \
505     do {                                                                    \
506         PRAGMA_DISABLE_PACKED_WARNING;                                      \
507         (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p,                 \
508         __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p,            \
509         __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p,            \
510         __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort))))  \
511             ((hptr), (x)), (void)0);                                        \
512         PRAGMA_REENABLE_PACKED_WARNING;                                     \
513     } while (0)
514 
515 #define __get_user_e(x, hptr, e)                                            \
516     do {                                                                    \
517         PRAGMA_DISABLE_PACKED_WARNING;                                      \
518         ((x) = (typeof(*hptr))(                                             \
519         __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p,                 \
520         __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p,           \
521         __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p,            \
522         __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort))))  \
523             (hptr)), (void)0);                                              \
524         PRAGMA_REENABLE_PACKED_WARNING;                                     \
525     } while (0)
526 
527 
528 #ifdef TARGET_WORDS_BIGENDIAN
529 # define __put_user(x, hptr)  __put_user_e(x, hptr, be)
530 # define __get_user(x, hptr)  __get_user_e(x, hptr, be)
531 #else
532 # define __put_user(x, hptr)  __put_user_e(x, hptr, le)
533 # define __get_user(x, hptr)  __get_user_e(x, hptr, le)
534 #endif
535 
536 /* put_user()/get_user() take a guest address and check access */
537 /* These are usually used to access an atomic data type, such as an int,
538  * that has been passed by address.  These internally perform locking
539  * and unlocking on the data type.
540  */
541 #define put_user(x, gaddr, target_type)					\
542 ({									\
543     abi_ulong __gaddr = (gaddr);					\
544     target_type *__hptr;						\
545     abi_long __ret = 0;							\
546     if ((__hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0))) { \
547         __put_user((x), __hptr);				\
548         unlock_user(__hptr, __gaddr, sizeof(target_type));		\
549     } else								\
550         __ret = -TARGET_EFAULT;						\
551     __ret;								\
552 })
553 
554 #define get_user(x, gaddr, target_type)					\
555 ({									\
556     abi_ulong __gaddr = (gaddr);					\
557     target_type *__hptr;						\
558     abi_long __ret = 0;							\
559     if ((__hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1))) { \
560         __get_user((x), __hptr);				\
561         unlock_user(__hptr, __gaddr, 0);				\
562     } else {								\
563         /* avoid warning */						\
564         (x) = 0;							\
565         __ret = -TARGET_EFAULT;						\
566     }									\
567     __ret;								\
568 })
569 
570 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
571 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
572 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
573 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
574 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
575 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
576 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
577 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
578 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
579 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
580 
581 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
582 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
583 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
584 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
585 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
586 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
587 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
588 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
589 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
590 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
591 
592 /* copy_from_user() and copy_to_user() are usually used to copy data
593  * buffers between the target and host.  These internally perform
594  * locking/unlocking of the memory.
595  */
596 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
597 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
598 
599 /* Functions for accessing guest memory.  The tget and tput functions
600    read/write single values, byteswapping as necessary.  The lock_user function
601    gets a pointer to a contiguous area of guest memory, but does not perform
602    any byteswapping.  lock_user may return either a pointer to the guest
603    memory, or a temporary buffer.  */
604 
605 /* Lock an area of guest memory into the host.  If copy is true then the
606    host area will have the same contents as the guest.  */
607 static inline void *lock_user(int type, abi_ulong guest_addr, long len, int copy)
608 {
609     if (!access_ok(type, guest_addr, len))
610         return NULL;
611 #ifdef DEBUG_REMAP
612     {
613         void *addr;
614         addr = g_malloc(len);
615         if (copy)
616             memcpy(addr, g2h(guest_addr), len);
617         else
618             memset(addr, 0, len);
619         return addr;
620     }
621 #else
622     return g2h(guest_addr);
623 #endif
624 }
625 
626 /* Unlock an area of guest memory.  The first LEN bytes must be
627    flushed back to guest memory. host_ptr = NULL is explicitly
628    allowed and does nothing. */
629 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
630                                long len)
631 {
632 
633 #ifdef DEBUG_REMAP
634     if (!host_ptr)
635         return;
636     if (host_ptr == g2h(guest_addr))
637         return;
638     if (len > 0)
639         memcpy(g2h(guest_addr), host_ptr, len);
640     g_free(host_ptr);
641 #endif
642 }
643 
644 /* Return the length of a string in target memory or -TARGET_EFAULT if
645    access error. */
646 abi_long target_strlen(abi_ulong gaddr);
647 
648 /* Like lock_user but for null terminated strings.  */
649 static inline void *lock_user_string(abi_ulong guest_addr)
650 {
651     abi_long len;
652     len = target_strlen(guest_addr);
653     if (len < 0)
654         return NULL;
655     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
656 }
657 
658 /* Helper macros for locking/unlocking a target struct.  */
659 #define lock_user_struct(type, host_ptr, guest_addr, copy)	\
660     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
661 #define unlock_user_struct(host_ptr, guest_addr, copy)		\
662     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
663 
664 #include <pthread.h>
665 
666 static inline int is_error(abi_long ret)
667 {
668     return (abi_ulong)ret >= (abi_ulong)(-4096);
669 }
670 
671 /**
672  * preexit_cleanup: housekeeping before the guest exits
673  *
674  * env: the CPU state
675  * code: the exit code
676  */
677 void preexit_cleanup(CPUArchState *env, int code);
678 
679 /* Include target-specific struct and function definitions;
680  * they may need access to the target-independent structures
681  * above, so include them last.
682  */
683 #include "target_cpu.h"
684 #include "target_structs.h"
685 
686 #endif /* QEMU_H */
687