bsd-user/qemu.h

   1 /*
   2  *  qemu bsd user mode definition
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17 #ifndef QEMU_H
  18 #define QEMU_H
  19
  20 #include "cpu.h"
  21 #include "qemu/units.h"
  22 #include "exec/cpu_ldst.h"
  23 #include "exec/exec-all.h"
  24
  25 #undef DEBUG_REMAP
  26
  27 #include "exec/user/abitypes.h"
  28
  29 extern char **environ;
  30
  31 #include "exec/user/thunk.h"
  32 #include "target_arch.h"
  33 #include "syscall_defs.h"
  34 #include "target_syscall.h"
  35 #include "target_os_vmparam.h"
  36 #include "target_os_signal.h"
  37 #include "target.h"
  38 #include "exec/gdbstub.h"
  39 #include "qemu/clang-tsa.h"
  40
  41 #include "qemu-os.h"
  42 /*
  43  * This struct is used to hold certain information about the image.  Basically,
  44  * it replicates in user space what would be certain task_struct fields in the
  45  * kernel
  46  */
  47 struct image_info {
  48     abi_ulong load_bias;
  49     abi_ulong load_addr;
  50     abi_ulong start_code;
  51     abi_ulong end_code;
  52     abi_ulong start_data;
  53     abi_ulong end_data;
  54     abi_ulong brk;
  55     abi_ulong rss;
  56     abi_ulong start_stack;
  57     abi_ulong entry;
  58     abi_ulong code_offset;
  59     abi_ulong data_offset;
  60     abi_ulong arg_start;
  61     abi_ulong arg_end;
  62     uint32_t  elf_flags;
  63 };
  64
  65 struct emulated_sigtable {
  66     int pending; /* true if signal is pending */
  67     target_siginfo_t info;
  68 };
  69
  70 /*
  71  * NOTE: we force a big alignment so that the stack stored after is aligned too
  72  */
  73 typedef struct TaskState {
  74     pid_t ts_tid;     /* tid (or pid) of this task */
  75
  76     struct TaskState *next;
  77     struct bsd_binprm *bprm;
  78     struct image_info *info;
  79
  80     struct emulated_sigtable sync_signal;
  81     /*
  82      * TODO: Since we block all signals while returning to the main CPU
  83      * loop, this needn't be an array
  84      */
  85     struct emulated_sigtable sigtab[TARGET_NSIG];
  86     /*
  87      * Nonzero if process_pending_signals() needs to do something (either
  88      * handle a pending signal or unblock signals).
  89      * This flag is written from a signal handler so should be accessed via
  90      * the qatomic_read() and qatomic_set() functions. (It is not accessed
  91      * from multiple threads.)
  92      */
  93     int signal_pending;
  94     /* True if we're leaving a sigsuspend and sigsuspend_mask is valid. */
  95     bool in_sigsuspend;
  96     /*
  97      * This thread's signal mask, as requested by the guest program.
  98      * The actual signal mask of this thread may differ:
  99      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
 100      *  + sometimes we block all signals to avoid races
 101      */
 102     sigset_t signal_mask;
 103     /*
 104      * The signal mask imposed by a guest sigsuspend syscall, if we are
 105      * currently in the middle of such a syscall
 106      */
 107     sigset_t sigsuspend_mask;
 108
 109     /* This thread's sigaltstack, if it has one */
 110     struct target_sigaltstack sigaltstack_used;
 111 } __attribute__((aligned(16))) TaskState;
 112
 113 void stop_all_tasks(void);
 114 extern const char *qemu_uname_release;
 115
 116 /*
 117  * TARGET_ARG_MAX defines the number of bytes allocated for arguments
 118  * and envelope for the new program. 256k should suffice for a reasonable
 119  * maxiumum env+arg in 32-bit environments, bump it up to 512k for !ILP32
 120  * platforms.
 121  */
 122 #if TARGET_ABI_BITS > 32
 123 #define TARGET_ARG_MAX (512 * KiB)
 124 #else
 125 #define TARGET_ARG_MAX (256 * KiB)
 126 #endif
 127 #define MAX_ARG_PAGES (TARGET_ARG_MAX / TARGET_PAGE_SIZE)
 128
 129 /*
 130  * This structure is used to hold the arguments that are
 131  * used when loading binaries.
 132  */
 133 struct bsd_binprm {
 134         char buf[128];
 135         void *page[MAX_ARG_PAGES];
 136         abi_ulong p;
 137         abi_ulong stringp;
 138         int fd;
 139         int e_uid, e_gid;
 140         int argc, envc;
 141         char **argv;
 142         char **envp;
 143         char *filename;         /* (Given) Name of binary */
 144         char *fullpath;         /* Full path of binary */
 145         int (*core_dump)(int, CPUArchState *);
 146 };
 147
 148 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
 149 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
 150                               abi_ulong stringp);
 151 int loader_exec(const char *filename, char **argv, char **envp,
 152                 struct target_pt_regs *regs, struct image_info *infop,
 153                 struct bsd_binprm *bprm);
 154
 155 int load_elf_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
 156                     struct image_info *info);
 157 int load_flt_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
 158                     struct image_info *info);
 159 int is_target_elf_binary(int fd);
 160
 161 abi_long memcpy_to_target(abi_ulong dest, const void *src,
 162                           unsigned long len);
 163 void target_set_brk(abi_ulong new_brk);
 164 abi_long do_brk(abi_ulong new_brk);
 165 void syscall_init(void);
 166 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
 167                             abi_long arg2, abi_long arg3, abi_long arg4,
 168                             abi_long arg5, abi_long arg6, abi_long arg7,
 169                             abi_long arg8);
 170 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
 171                            abi_long arg2, abi_long arg3, abi_long arg4,
 172                            abi_long arg5, abi_long arg6);
 173 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
 174                             abi_long arg2, abi_long arg3, abi_long arg4,
 175                             abi_long arg5, abi_long arg6);
 176 void gemu_log(const char *fmt, ...) G_GNUC_PRINTF(1, 2);
 177 extern __thread CPUState *thread_cpu;
 178 void cpu_loop(CPUArchState *env);
 179 char *target_strerror(int err);
 180 int get_osversion(void);
 181 void fork_start(void);
 182 void fork_end(int child);
 183
 184 #include "qemu/log.h"
 185
 186 /* strace.c */
 187 struct syscallname {
 188     int nr;
 189     const char *name;
 190     const char *format;
 191     void (*call)(const struct syscallname *,
 192                  abi_long, abi_long, abi_long,
 193                  abi_long, abi_long, abi_long);
 194     void (*result)(const struct syscallname *, abi_long);
 195 };
 196
 197 void
 198 print_freebsd_syscall(int num,
 199                       abi_long arg1, abi_long arg2, abi_long arg3,
 200                       abi_long arg4, abi_long arg5, abi_long arg6);
 201 void print_freebsd_syscall_ret(int num, abi_long ret);
 202 void
 203 print_netbsd_syscall(int num,
 204                      abi_long arg1, abi_long arg2, abi_long arg3,
 205                      abi_long arg4, abi_long arg5, abi_long arg6);
 206 void print_netbsd_syscall_ret(int num, abi_long ret);
 207 void
 208 print_openbsd_syscall(int num,
 209                       abi_long arg1, abi_long arg2, abi_long arg3,
 210                       abi_long arg4, abi_long arg5, abi_long arg6);
 211 void print_openbsd_syscall_ret(int num, abi_long ret);
 212 /**
 213  * print_taken_signal:
 214  * @target_signum: target signal being taken
 215  * @tinfo: target_siginfo_t which will be passed to the guest for the signal
 216  *
 217  * Print strace output indicating that this signal is being taken by the guest,
 218  * in a format similar to:
 219  * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
 220  */
 221 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
 222 extern int do_strace;
 223
 224 /* mmap.c */
 225 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
 226 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
 227                      int flags, int fd, off_t offset);
 228 int target_munmap(abi_ulong start, abi_ulong len);
 229 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
 230                        abi_ulong new_size, unsigned long flags,
 231                        abi_ulong new_addr);
 232 int target_msync(abi_ulong start, abi_ulong len, int flags);
 233 extern abi_ulong mmap_next_start;
 234 abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size);
 235 void TSA_NO_TSA mmap_fork_start(void);
 236 void TSA_NO_TSA mmap_fork_end(int child);
 237
 238 /* main.c */
 239 extern char qemu_proc_pathname[];
 240 extern unsigned long target_maxtsiz;
 241 extern unsigned long target_dfldsiz;
 242 extern unsigned long target_maxdsiz;
 243 extern unsigned long target_dflssiz;
 244 extern unsigned long target_maxssiz;
 245 extern unsigned long target_sgrowsiz;
 246
 247 /* os-syscall.c */
 248 abi_long get_errno(abi_long ret);
 249 bool is_error(abi_long ret);
 250 int host_to_target_errno(int err);
 251
 252 /* os-sys.c */
 253 abi_long do_freebsd_sysctl(CPUArchState *env, abi_ulong namep, int32_t namelen,
 254         abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen);
 255 abi_long do_freebsd_sysctlbyname(CPUArchState *env, abi_ulong namep,
 256         int32_t namelen, abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp,
 257         abi_ulong newlen);
 258 abi_long do_freebsd_sysarch(void *cpu_env, abi_long arg1, abi_long arg2);
 259
 260 /* user access */
 261
 262 #define VERIFY_READ  PAGE_READ
 263 #define VERIFY_WRITE (PAGE_READ | PAGE_WRITE)
 264
 265 static inline bool access_ok(int type, abi_ulong addr, abi_ulong size)
 266 {
 267     return page_check_range((target_ulong)addr, size, type);
 268 }
 269
 270 /*
 271  * NOTE __get_user and __put_user use host pointers and don't check access.
 272  *
 273  * These are usually used to access struct data members once the struct has been
 274  * locked - usually with lock_user_struct().
 275  */
 276
 277 /*
 278  * Tricky points:
 279  * - Use __builtin_choose_expr to avoid type promotion from ?:,
 280  * - Invalid sizes result in a compile time error stemming from
 281  *   the fact that abort has no parameters.
 282  * - It's easier to use the endian-specific unaligned load/store
 283  *   functions than host-endian unaligned load/store plus tswapN.
 284  * - The pragmas are necessary only to silence a clang false-positive
 285  *   warning: see https://bugs.llvm.org/show_bug.cgi?id=39113 .
 286  * - gcc has bugs in its _Pragma() support in some versions, eg
 287  *   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83256 -- so we only
 288  *   include the warning-suppression pragmas for clang
 289  */
 290 #if defined(__clang__) && __has_warning("-Waddress-of-packed-member")
 291 #define PRAGMA_DISABLE_PACKED_WARNING                                   \
 292     _Pragma("GCC diagnostic push");                                     \
 293     _Pragma("GCC diagnostic ignored \"-Waddress-of-packed-member\"")
 294
 295 #define PRAGMA_REENABLE_PACKED_WARNING          \
 296     _Pragma("GCC diagnostic pop")
 297
 298 #else
 299 #define PRAGMA_DISABLE_PACKED_WARNING
 300 #define PRAGMA_REENABLE_PACKED_WARNING
 301 #endif
 302
 303 #define __put_user_e(x, hptr, e)                                            \
 304     do {                                                                    \
 305         PRAGMA_DISABLE_PACKED_WARNING;                                      \
 306         (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p,                 \
 307         __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p,            \
 308         __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p,            \
 309         __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort))))  \
 310             ((hptr), (x)), (void)0);                                        \
 311         PRAGMA_REENABLE_PACKED_WARNING;                                     \
 312     } while (0)
 313
 314 #define __get_user_e(x, hptr, e)                                            \
 315     do {                                                                    \
 316         PRAGMA_DISABLE_PACKED_WARNING;                                      \
 317         ((x) = (typeof(*hptr))(                                             \
 318         __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p,                 \
 319         __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p,           \
 320         __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p,            \
 321         __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort))))  \
 322             (hptr)), (void)0);                                              \
 323         PRAGMA_REENABLE_PACKED_WARNING;                                     \
 324     } while (0)
 325
 326
 327 #if TARGET_BIG_ENDIAN
 328 # define __put_user(x, hptr)  __put_user_e(x, hptr, be)
 329 # define __get_user(x, hptr)  __get_user_e(x, hptr, be)
 330 #else
 331 # define __put_user(x, hptr)  __put_user_e(x, hptr, le)
 332 # define __get_user(x, hptr)  __get_user_e(x, hptr, le)
 333 #endif
 334
 335 /*
 336  * put_user()/get_user() take a guest address and check access
 337  *
 338  * These are usually used to access an atomic data type, such as an int, that
 339  * has been passed by address.  These internally perform locking and unlocking
 340  * on the data type.
 341  */
 342 #define put_user(x, gaddr, target_type)                                 \
 343 ({                                                                      \
 344     abi_ulong __gaddr = (gaddr);                                        \
 345     target_type *__hptr;                                                \
 346     abi_long __ret = 0;                                                 \
 347     __hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0);  \
 348     if (__hptr) {                                                       \
 349         __put_user((x), __hptr);                                        \
 350         unlock_user(__hptr, __gaddr, sizeof(target_type));              \
 351     } else                                                              \
 352         __ret = -TARGET_EFAULT;                                         \
 353     __ret;                                                              \
 354 })
 355
 356 #define get_user(x, gaddr, target_type)                                 \
 357 ({                                                                      \
 358     abi_ulong __gaddr = (gaddr);                                        \
 359     target_type *__hptr;                                                \
 360     abi_long __ret = 0;                                                 \
 361     __hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1);   \
 362     if (__hptr) {                                                       \
 363         __get_user((x), __hptr);                                        \
 364         unlock_user(__hptr, __gaddr, 0);                                \
 365     } else {                                                            \
 366         (x) = 0;                                                        \
 367         __ret = -TARGET_EFAULT;                                         \
 368     }                                                                   \
 369     __ret;                                                              \
 370 })
 371
 372 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
 373 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
 374 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
 375 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
 376 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
 377 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
 378 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
 379 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
 380 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
 381 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
 382
 383 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
 384 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
 385 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
 386 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
 387 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
 388 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
 389 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
 390 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
 391 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
 392 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
 393
 394 /*
 395  * copy_from_user() and copy_to_user() are usually used to copy data
 396  * buffers between the target and host.  These internally perform
 397  * locking/unlocking of the memory.
 398  */
 399 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
 400 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
 401
 402 /*
 403  * Functions for accessing guest memory.  The tget and tput functions
 404  * read/write single values, byteswapping as necessary.  The lock_user function
 405  * gets a pointer to a contiguous area of guest memory, but does not perform
 406  * any byteswapping.  lock_user may return either a pointer to the guest
 407  * memory, or a temporary buffer.
 408  */
 409
 410 /*
 411  * Lock an area of guest memory into the host.  If copy is true then the
 412  * host area will have the same contents as the guest.
 413  */
 414 static inline void *lock_user(int type, abi_ulong guest_addr, long len,
 415                               int copy)
 416 {
 417     if (!access_ok(type, guest_addr, len)) {
 418         return NULL;
 419     }
 420 #ifdef DEBUG_REMAP
 421     {
 422         void *addr;
 423         addr = g_malloc(len);
 424         if (copy) {
 425             memcpy(addr, g2h_untagged(guest_addr), len);
 426         } else {
 427             memset(addr, 0, len);
 428         }
 429         return addr;
 430     }
 431 #else
 432     return g2h_untagged(guest_addr);
 433 #endif
 434 }
 435
 436 /*
 437  * Unlock an area of guest memory.  The first LEN bytes must be flushed back to
 438  * guest memory. host_ptr = NULL is explicitly allowed and does nothing.
 439  */
 440 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
 441                                long len)
 442 {
 443
 444 #ifdef DEBUG_REMAP
 445     if (!host_ptr) {
 446         return;
 447     }
 448     if (host_ptr == g2h_untagged(guest_addr)) {
 449         return;
 450     }
 451     if (len > 0) {
 452         memcpy(g2h_untagged(guest_addr), host_ptr, len);
 453     }
 454     g_free(host_ptr);
 455 #endif
 456 }
 457
 458 /*
 459  * Return the length of a string in target memory or -TARGET_EFAULT if access
 460  * error.
 461  */
 462 abi_long target_strlen(abi_ulong gaddr);
 463
 464 /* Like lock_user but for null terminated strings.  */
 465 static inline void *lock_user_string(abi_ulong guest_addr)
 466 {
 467     abi_long len;
 468     len = target_strlen(guest_addr);
 469     if (len < 0) {
 470         return NULL;
 471     }
 472     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
 473 }
 474
 475 /* Helper macros for locking/unlocking a target struct.  */
 476 #define lock_user_struct(type, host_ptr, guest_addr, copy)      \
 477     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
 478 #define unlock_user_struct(host_ptr, guest_addr, copy)          \
 479     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
 480
 481 static inline uint64_t target_arg64(uint32_t word0, uint32_t word1)
 482 {
 483 #if TARGET_ABI_BITS == 32
 484 #if TARGET_BIG_ENDIAN
 485     return ((uint64_t)word0 << 32) | word1;
 486 #else
 487     return ((uint64_t)word1 << 32) | word0;
 488 #endif
 489 #else /* TARGET_ABI_BITS != 32 */
 490     return word0;
 491 #endif /* TARGET_ABI_BITS != 32 */
 492 }
 493
 494 #include <pthread.h>
 495
 496 #include "user/safe-syscall.h"
 497
 498 #endif /* QEMU_H */