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