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