xref: /openbmc/qemu/bsd-user/qemu.h (revision 25e2cfbb)
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 /*
42  * This struct is used to hold certain information about the image.  Basically,
43  * it replicates in user space what would be certain task_struct fields in the
44  * kernel
45  */
46 struct image_info {
47     abi_ulong load_bias;
48     abi_ulong load_addr;
49     abi_ulong start_code;
50     abi_ulong end_code;
51     abi_ulong start_data;
52     abi_ulong end_data;
53     abi_ulong brk;
54     abi_ulong rss;
55     abi_ulong start_stack;
56     abi_ulong entry;
57     abi_ulong code_offset;
58     abi_ulong data_offset;
59     abi_ulong arg_start;
60     abi_ulong arg_end;
61     uint32_t  elf_flags;
62 };
63 
64 struct emulated_sigtable {
65     int pending; /* true if signal is pending */
66     target_siginfo_t info;
67 };
68 
69 /*
70  * NOTE: we force a big alignment so that the stack stored after is aligned too
71  */
72 typedef struct TaskState {
73     pid_t ts_tid;     /* tid (or pid) of this task */
74 
75     struct TaskState *next;
76     struct bsd_binprm *bprm;
77     struct image_info *info;
78 
79     struct emulated_sigtable sync_signal;
80     /*
81      * TODO: Since we block all signals while returning to the main CPU
82      * loop, this needn't be an array
83      */
84     struct emulated_sigtable sigtab[TARGET_NSIG];
85     /*
86      * Nonzero if process_pending_signals() needs to do something (either
87      * handle a pending signal or unblock signals).
88      * This flag is written from a signal handler so should be accessed via
89      * the qatomic_read() and qatomic_set() functions. (It is not accessed
90      * from multiple threads.)
91      */
92     int signal_pending;
93     /* True if we're leaving a sigsuspend and sigsuspend_mask is valid. */
94     bool in_sigsuspend;
95     /*
96      * This thread's signal mask, as requested by the guest program.
97      * The actual signal mask of this thread may differ:
98      *  + we don't let SIGSEGV and SIGBUS be blocked while running guest code
99      *  + sometimes we block all signals to avoid races
100      */
101     sigset_t signal_mask;
102     /*
103      * The signal mask imposed by a guest sigsuspend syscall, if we are
104      * currently in the middle of such a syscall
105      */
106     sigset_t sigsuspend_mask;
107 
108     /* This thread's sigaltstack, if it has one */
109     struct target_sigaltstack sigaltstack_used;
110 } __attribute__((aligned(16))) TaskState;
111 
112 void stop_all_tasks(void);
113 extern const char *qemu_uname_release;
114 
115 /*
116  * TARGET_ARG_MAX defines the number of bytes allocated for arguments
117  * and envelope for the new program. 256k should suffice for a reasonable
118  * maxiumum env+arg in 32-bit environments, bump it up to 512k for !ILP32
119  * platforms.
120  */
121 #if TARGET_ABI_BITS > 32
122 #define TARGET_ARG_MAX (512 * KiB)
123 #else
124 #define TARGET_ARG_MAX (256 * KiB)
125 #endif
126 #define MAX_ARG_PAGES (TARGET_ARG_MAX / TARGET_PAGE_SIZE)
127 
128 /*
129  * This structure is used to hold the arguments that are
130  * used when loading binaries.
131  */
132 struct bsd_binprm {
133         char buf[128];
134         void *page[MAX_ARG_PAGES];
135         abi_ulong p;
136         abi_ulong stringp;
137         int fd;
138         int e_uid, e_gid;
139         int argc, envc;
140         char **argv;
141         char **envp;
142         char *filename;         /* (Given) Name of binary */
143         char *fullpath;         /* Full path of binary */
144         int (*core_dump)(int, CPUArchState *);
145 };
146 
147 void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
148 abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
149                               abi_ulong stringp);
150 int loader_exec(const char *filename, char **argv, char **envp,
151                 struct target_pt_regs *regs, struct image_info *infop,
152                 struct bsd_binprm *bprm);
153 
154 int load_elf_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
155                     struct image_info *info);
156 int load_flt_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
157                     struct image_info *info);
158 int is_target_elf_binary(int fd);
159 
160 abi_long memcpy_to_target(abi_ulong dest, const void *src,
161                           unsigned long len);
162 void target_set_brk(abi_ulong new_brk);
163 abi_long do_brk(abi_ulong new_brk);
164 void syscall_init(void);
165 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
166                             abi_long arg2, abi_long arg3, abi_long arg4,
167                             abi_long arg5, abi_long arg6, abi_long arg7,
168                             abi_long arg8);
169 abi_long do_netbsd_syscall(void *cpu_env, int num, abi_long arg1,
170                            abi_long arg2, abi_long arg3, abi_long arg4,
171                            abi_long arg5, abi_long arg6);
172 abi_long do_openbsd_syscall(void *cpu_env, int num, abi_long arg1,
173                             abi_long arg2, abi_long arg3, abi_long arg4,
174                             abi_long arg5, abi_long arg6);
175 void gemu_log(const char *fmt, ...) G_GNUC_PRINTF(1, 2);
176 extern __thread CPUState *thread_cpu;
177 void cpu_loop(CPUArchState *env);
178 char *target_strerror(int err);
179 int get_osversion(void);
180 void fork_start(void);
181 void fork_end(int child);
182 
183 #include "qemu/log.h"
184 
185 /* strace.c */
186 struct syscallname {
187     int nr;
188     const char *name;
189     const char *format;
190     void (*call)(const struct syscallname *,
191                  abi_long, abi_long, abi_long,
192                  abi_long, abi_long, abi_long);
193     void (*result)(const struct syscallname *, abi_long);
194 };
195 
196 void
197 print_freebsd_syscall(int num,
198                       abi_long arg1, abi_long arg2, abi_long arg3,
199                       abi_long arg4, abi_long arg5, abi_long arg6);
200 void print_freebsd_syscall_ret(int num, abi_long ret);
201 void
202 print_netbsd_syscall(int num,
203                      abi_long arg1, abi_long arg2, abi_long arg3,
204                      abi_long arg4, abi_long arg5, abi_long arg6);
205 void print_netbsd_syscall_ret(int num, abi_long ret);
206 void
207 print_openbsd_syscall(int num,
208                       abi_long arg1, abi_long arg2, abi_long arg3,
209                       abi_long arg4, abi_long arg5, abi_long arg6);
210 void print_openbsd_syscall_ret(int num, abi_long ret);
211 /**
212  * print_taken_signal:
213  * @target_signum: target signal being taken
214  * @tinfo: target_siginfo_t which will be passed to the guest for the signal
215  *
216  * Print strace output indicating that this signal is being taken by the guest,
217  * in a format similar to:
218  * --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} ---
219  */
220 void print_taken_signal(int target_signum, const target_siginfo_t *tinfo);
221 extern int do_strace;
222 
223 /* mmap.c */
224 int target_mprotect(abi_ulong start, abi_ulong len, int prot);
225 abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
226                      int flags, int fd, off_t offset);
227 int target_munmap(abi_ulong start, abi_ulong len);
228 abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size,
229                        abi_ulong new_size, unsigned long flags,
230                        abi_ulong new_addr);
231 int target_msync(abi_ulong start, abi_ulong len, int flags);
232 extern abi_ulong mmap_next_start;
233 abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size);
234 void TSA_NO_TSA mmap_fork_start(void);
235 void TSA_NO_TSA mmap_fork_end(int child);
236 
237 /* main.c */
238 extern char qemu_proc_pathname[];
239 extern unsigned long target_maxtsiz;
240 extern unsigned long target_dfldsiz;
241 extern unsigned long target_maxdsiz;
242 extern unsigned long target_dflssiz;
243 extern unsigned long target_maxssiz;
244 extern unsigned long target_sgrowsiz;
245 
246 /* os-syscall.c */
247 abi_long get_errno(abi_long ret);
248 bool is_error(abi_long ret);
249 int host_to_target_errno(int err);
250 
251 /* os-sys.c */
252 abi_long do_freebsd_sysctl(CPUArchState *env, abi_ulong namep, int32_t namelen,
253         abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp, abi_ulong newlen);
254 abi_long do_freebsd_sysctlbyname(CPUArchState *env, abi_ulong namep,
255         int32_t namelen, abi_ulong oldp, abi_ulong oldlenp, abi_ulong newp,
256         abi_ulong newlen);
257 abi_long do_freebsd_sysarch(void *cpu_env, abi_long arg1, abi_long arg2);
258 
259 /* user access */
260 
261 #define VERIFY_READ  PAGE_READ
262 #define VERIFY_WRITE (PAGE_READ | PAGE_WRITE)
263 
264 static inline bool access_ok(int type, abi_ulong addr, abi_ulong size)
265 {
266     return page_check_range((target_ulong)addr, size, type);
267 }
268 
269 /*
270  * NOTE __get_user and __put_user use host pointers and don't check access.
271  *
272  * These are usually used to access struct data members once the struct has been
273  * locked - usually with lock_user_struct().
274  */
275 #define __put_user(x, hptr)\
276 ({\
277     int size = sizeof(*hptr);\
278     switch (size) {\
279     case 1:\
280         *(uint8_t *)(hptr) = (uint8_t)(typeof(*hptr))(x);\
281         break;\
282     case 2:\
283         *(uint16_t *)(hptr) = tswap16((typeof(*hptr))(x));\
284         break;\
285     case 4:\
286         *(uint32_t *)(hptr) = tswap32((typeof(*hptr))(x));\
287         break;\
288     case 8:\
289         *(uint64_t *)(hptr) = tswap64((typeof(*hptr))(x));\
290         break;\
291     default:\
292         abort();\
293     } \
294     0;\
295 })
296 
297 #define __get_user(x, hptr) \
298 ({\
299     int size = sizeof(*hptr);\
300     switch (size) {\
301     case 1:\
302         x = (typeof(*hptr))*(uint8_t *)(hptr);\
303         break;\
304     case 2:\
305         x = (typeof(*hptr))tswap16(*(uint16_t *)(hptr));\
306         break;\
307     case 4:\
308         x = (typeof(*hptr))tswap32(*(uint32_t *)(hptr));\
309         break;\
310     case 8:\
311         x = (typeof(*hptr))tswap64(*(uint64_t *)(hptr));\
312         break;\
313     default:\
314         x = 0;\
315         abort();\
316     } \
317     0;\
318 })
319 
320 /*
321  * put_user()/get_user() take a guest address and check access
322  *
323  * These are usually used to access an atomic data type, such as an int, that
324  * has been passed by address.  These internally perform locking and unlocking
325  * on the data type.
326  */
327 #define put_user(x, gaddr, target_type)                                 \
328 ({                                                                      \
329     abi_ulong __gaddr = (gaddr);                                        \
330     target_type *__hptr;                                                \
331     abi_long __ret;                                                     \
332     __hptr = lock_user(VERIFY_WRITE, __gaddr, sizeof(target_type), 0);  \
333     if (__hptr) {                                                       \
334         __ret = __put_user((x), __hptr);                                \
335         unlock_user(__hptr, __gaddr, sizeof(target_type));              \
336     } else                                                              \
337         __ret = -TARGET_EFAULT;                                         \
338     __ret;                                                              \
339 })
340 
341 #define get_user(x, gaddr, target_type)                                 \
342 ({                                                                      \
343     abi_ulong __gaddr = (gaddr);                                        \
344     target_type *__hptr;                                                \
345     abi_long __ret;                                                     \
346     __hptr = lock_user(VERIFY_READ, __gaddr, sizeof(target_type), 1);   \
347     if (__hptr) {                                                       \
348         __ret = __get_user((x), __hptr);                                \
349         unlock_user(__hptr, __gaddr, 0);                                \
350     } else {                                                            \
351         (x) = 0;                                                        \
352         __ret = -TARGET_EFAULT;                                         \
353     }                                                                   \
354     __ret;                                                              \
355 })
356 
357 #define put_user_ual(x, gaddr) put_user((x), (gaddr), abi_ulong)
358 #define put_user_sal(x, gaddr) put_user((x), (gaddr), abi_long)
359 #define put_user_u64(x, gaddr) put_user((x), (gaddr), uint64_t)
360 #define put_user_s64(x, gaddr) put_user((x), (gaddr), int64_t)
361 #define put_user_u32(x, gaddr) put_user((x), (gaddr), uint32_t)
362 #define put_user_s32(x, gaddr) put_user((x), (gaddr), int32_t)
363 #define put_user_u16(x, gaddr) put_user((x), (gaddr), uint16_t)
364 #define put_user_s16(x, gaddr) put_user((x), (gaddr), int16_t)
365 #define put_user_u8(x, gaddr)  put_user((x), (gaddr), uint8_t)
366 #define put_user_s8(x, gaddr)  put_user((x), (gaddr), int8_t)
367 
368 #define get_user_ual(x, gaddr) get_user((x), (gaddr), abi_ulong)
369 #define get_user_sal(x, gaddr) get_user((x), (gaddr), abi_long)
370 #define get_user_u64(x, gaddr) get_user((x), (gaddr), uint64_t)
371 #define get_user_s64(x, gaddr) get_user((x), (gaddr), int64_t)
372 #define get_user_u32(x, gaddr) get_user((x), (gaddr), uint32_t)
373 #define get_user_s32(x, gaddr) get_user((x), (gaddr), int32_t)
374 #define get_user_u16(x, gaddr) get_user((x), (gaddr), uint16_t)
375 #define get_user_s16(x, gaddr) get_user((x), (gaddr), int16_t)
376 #define get_user_u8(x, gaddr)  get_user((x), (gaddr), uint8_t)
377 #define get_user_s8(x, gaddr)  get_user((x), (gaddr), int8_t)
378 
379 /*
380  * copy_from_user() and copy_to_user() are usually used to copy data
381  * buffers between the target and host.  These internally perform
382  * locking/unlocking of the memory.
383  */
384 abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len);
385 abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len);
386 
387 /*
388  * Functions for accessing guest memory.  The tget and tput functions
389  * read/write single values, byteswapping as necessary.  The lock_user function
390  * gets a pointer to a contiguous area of guest memory, but does not perform
391  * any byteswapping.  lock_user may return either a pointer to the guest
392  * memory, or a temporary buffer.
393  */
394 
395 /*
396  * Lock an area of guest memory into the host.  If copy is true then the
397  * host area will have the same contents as the guest.
398  */
399 static inline void *lock_user(int type, abi_ulong guest_addr, long len,
400                               int copy)
401 {
402     if (!access_ok(type, guest_addr, len)) {
403         return NULL;
404     }
405 #ifdef DEBUG_REMAP
406     {
407         void *addr;
408         addr = g_malloc(len);
409         if (copy) {
410             memcpy(addr, g2h_untagged(guest_addr), len);
411         } else {
412             memset(addr, 0, len);
413         }
414         return addr;
415     }
416 #else
417     return g2h_untagged(guest_addr);
418 #endif
419 }
420 
421 /*
422  * Unlock an area of guest memory.  The first LEN bytes must be flushed back to
423  * guest memory. host_ptr = NULL is explicitly allowed and does nothing.
424  */
425 static inline void unlock_user(void *host_ptr, abi_ulong guest_addr,
426                                long len)
427 {
428 
429 #ifdef DEBUG_REMAP
430     if (!host_ptr) {
431         return;
432     }
433     if (host_ptr == g2h_untagged(guest_addr)) {
434         return;
435     }
436     if (len > 0) {
437         memcpy(g2h_untagged(guest_addr), host_ptr, len);
438     }
439     g_free(host_ptr);
440 #endif
441 }
442 
443 /*
444  * Return the length of a string in target memory or -TARGET_EFAULT if access
445  * error.
446  */
447 abi_long target_strlen(abi_ulong gaddr);
448 
449 /* Like lock_user but for null terminated strings.  */
450 static inline void *lock_user_string(abi_ulong guest_addr)
451 {
452     abi_long len;
453     len = target_strlen(guest_addr);
454     if (len < 0) {
455         return NULL;
456     }
457     return lock_user(VERIFY_READ, guest_addr, (long)(len + 1), 1);
458 }
459 
460 /* Helper macros for locking/unlocking a target struct.  */
461 #define lock_user_struct(type, host_ptr, guest_addr, copy)      \
462     (host_ptr = lock_user(type, guest_addr, sizeof(*host_ptr), copy))
463 #define unlock_user_struct(host_ptr, guest_addr, copy)          \
464     unlock_user(host_ptr, guest_addr, (copy) ? sizeof(*host_ptr) : 0)
465 
466 static inline uint64_t target_arg64(uint32_t word0, uint32_t word1)
467 {
468 #if TARGET_ABI_BITS == 32
469 #if TARGET_BIG_ENDIAN
470     return ((uint64_t)word0 << 32) | word1;
471 #else
472     return ((uint64_t)word1 << 32) | word0;
473 #endif
474 #else /* TARGET_ABI_BITS != 32 */
475     return word0;
476 #endif /* TARGET_ABI_BITS != 32 */
477 }
478 
479 #include <pthread.h>
480 
481 #include "user/safe-syscall.h"
482 
483 #endif /* QEMU_H */
484