target/arm: Make SYS_HEAPINFO work with RAM that doesn't start at 0
[qemu.git] / target / arm / arm-semi.c
1 /*
2 * Arm "Angel" semihosting syscalls
3 *
4 * Copyright (c) 2005, 2007 CodeSourcery.
5 * Copyright (c) 2019 Linaro
6 * Written by Paul Brook.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 *
21 * ARM Semihosting is documented in:
22 * Semihosting for AArch32 and AArch64 Release 2.0
23 * https://static.docs.arm.com/100863/0200/semihosting.pdf
24 */
25
26 #include "qemu/osdep.h"
27
28 #include "cpu.h"
29 #include "hw/semihosting/semihost.h"
30 #include "hw/semihosting/console.h"
31 #include "qemu/log.h"
32 #ifdef CONFIG_USER_ONLY
33 #include "qemu.h"
34
35 #define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)
36 #else
37 #include "exec/gdbstub.h"
38 #include "qemu/cutils.h"
39 #include "hw/arm/boot.h"
40 #endif
41
42 #define TARGET_SYS_OPEN 0x01
43 #define TARGET_SYS_CLOSE 0x02
44 #define TARGET_SYS_WRITEC 0x03
45 #define TARGET_SYS_WRITE0 0x04
46 #define TARGET_SYS_WRITE 0x05
47 #define TARGET_SYS_READ 0x06
48 #define TARGET_SYS_READC 0x07
49 #define TARGET_SYS_ISTTY 0x09
50 #define TARGET_SYS_SEEK 0x0a
51 #define TARGET_SYS_FLEN 0x0c
52 #define TARGET_SYS_TMPNAM 0x0d
53 #define TARGET_SYS_REMOVE 0x0e
54 #define TARGET_SYS_RENAME 0x0f
55 #define TARGET_SYS_CLOCK 0x10
56 #define TARGET_SYS_TIME 0x11
57 #define TARGET_SYS_SYSTEM 0x12
58 #define TARGET_SYS_ERRNO 0x13
59 #define TARGET_SYS_GET_CMDLINE 0x15
60 #define TARGET_SYS_HEAPINFO 0x16
61 #define TARGET_SYS_EXIT 0x18
62 #define TARGET_SYS_SYNCCACHE 0x19
63 #define TARGET_SYS_EXIT_EXTENDED 0x20
64
65 /* ADP_Stopped_ApplicationExit is used for exit(0),
66 * anything else is implemented as exit(1) */
67 #define ADP_Stopped_ApplicationExit (0x20026)
68
69 #ifndef O_BINARY
70 #define O_BINARY 0
71 #endif
72
73 #define GDB_O_RDONLY 0x000
74 #define GDB_O_WRONLY 0x001
75 #define GDB_O_RDWR 0x002
76 #define GDB_O_APPEND 0x008
77 #define GDB_O_CREAT 0x200
78 #define GDB_O_TRUNC 0x400
79 #define GDB_O_BINARY 0
80
81 static int gdb_open_modeflags[12] = {
82 GDB_O_RDONLY,
83 GDB_O_RDONLY | GDB_O_BINARY,
84 GDB_O_RDWR,
85 GDB_O_RDWR | GDB_O_BINARY,
86 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
87 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
88 GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
89 GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
90 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
91 GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY,
92 GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
93 GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY
94 };
95
96 static int open_modeflags[12] = {
97 O_RDONLY,
98 O_RDONLY | O_BINARY,
99 O_RDWR,
100 O_RDWR | O_BINARY,
101 O_WRONLY | O_CREAT | O_TRUNC,
102 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
103 O_RDWR | O_CREAT | O_TRUNC,
104 O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
105 O_WRONLY | O_CREAT | O_APPEND,
106 O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
107 O_RDWR | O_CREAT | O_APPEND,
108 O_RDWR | O_CREAT | O_APPEND | O_BINARY
109 };
110
111 typedef enum GuestFDType {
112 GuestFDUnused = 0,
113 GuestFDHost = 1,
114 GuestFDGDB = 2,
115 GuestFDFeatureFile = 3,
116 } GuestFDType;
117
118 /*
119 * Guest file descriptors are integer indexes into an array of
120 * these structures (we will dynamically resize as necessary).
121 */
122 typedef struct GuestFD {
123 GuestFDType type;
124 union {
125 int hostfd;
126 target_ulong featurefile_offset;
127 };
128 } GuestFD;
129
130 static GArray *guestfd_array;
131
132 /*
133 * Allocate a new guest file descriptor and return it; if we
134 * couldn't allocate a new fd then return -1.
135 * This is a fairly simplistic implementation because we don't
136 * expect that most semihosting guest programs will make very
137 * heavy use of opening and closing fds.
138 */
139 static int alloc_guestfd(void)
140 {
141 guint i;
142
143 if (!guestfd_array) {
144 /* New entries zero-initialized, i.e. type GuestFDUnused */
145 guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD));
146 }
147
148 /* SYS_OPEN should return nonzero handle on success. Start guestfd from 1 */
149 for (i = 1; i < guestfd_array->len; i++) {
150 GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i);
151
152 if (gf->type == GuestFDUnused) {
153 return i;
154 }
155 }
156
157 /* All elements already in use: expand the array */
158 g_array_set_size(guestfd_array, i + 1);
159 return i;
160 }
161
162 /*
163 * Look up the guestfd in the data structure; return NULL
164 * for out of bounds, but don't check whether the slot is unused.
165 * This is used internally by the other guestfd functions.
166 */
167 static GuestFD *do_get_guestfd(int guestfd)
168 {
169 if (!guestfd_array) {
170 return NULL;
171 }
172
173 if (guestfd <= 0 || guestfd >= guestfd_array->len) {
174 return NULL;
175 }
176
177 return &g_array_index(guestfd_array, GuestFD, guestfd);
178 }
179
180 /*
181 * Associate the specified guest fd (which must have been
182 * allocated via alloc_fd() and not previously used) with
183 * the specified host/gdb fd.
184 */
185 static void associate_guestfd(int guestfd, int hostfd)
186 {
187 GuestFD *gf = do_get_guestfd(guestfd);
188
189 assert(gf);
190 gf->type = use_gdb_syscalls() ? GuestFDGDB : GuestFDHost;
191 gf->hostfd = hostfd;
192 }
193
194 /*
195 * Deallocate the specified guest file descriptor. This doesn't
196 * close the host fd, it merely undoes the work of alloc_fd().
197 */
198 static void dealloc_guestfd(int guestfd)
199 {
200 GuestFD *gf = do_get_guestfd(guestfd);
201
202 assert(gf);
203 gf->type = GuestFDUnused;
204 }
205
206 /*
207 * Given a guest file descriptor, get the associated struct.
208 * If the fd is not valid, return NULL. This is the function
209 * used by the various semihosting calls to validate a handle
210 * from the guest.
211 * Note: calling alloc_guestfd() or dealloc_guestfd() will
212 * invalidate any GuestFD* obtained by calling this function.
213 */
214 static GuestFD *get_guestfd(int guestfd)
215 {
216 GuestFD *gf = do_get_guestfd(guestfd);
217
218 if (!gf || gf->type == GuestFDUnused) {
219 return NULL;
220 }
221 return gf;
222 }
223
224 /*
225 * The semihosting API has no concept of its errno being thread-safe,
226 * as the API design predates SMP CPUs and was intended as a simple
227 * real-hardware set of debug functionality. For QEMU, we make the
228 * errno be per-thread in linux-user mode; in softmmu it is a simple
229 * global, and we assume that the guest takes care of avoiding any races.
230 */
231 #ifndef CONFIG_USER_ONLY
232 static target_ulong syscall_err;
233
234 #include "exec/softmmu-semi.h"
235 #endif
236
237 static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code)
238 {
239 if (code == (uint32_t)-1) {
240 #ifdef CONFIG_USER_ONLY
241 CPUState *cs = env_cpu(env);
242 TaskState *ts = cs->opaque;
243
244 ts->swi_errno = errno;
245 #else
246 syscall_err = errno;
247 #endif
248 }
249 return code;
250 }
251
252 static inline uint32_t get_swi_errno(CPUARMState *env)
253 {
254 #ifdef CONFIG_USER_ONLY
255 CPUState *cs = env_cpu(env);
256 TaskState *ts = cs->opaque;
257
258 return ts->swi_errno;
259 #else
260 return syscall_err;
261 #endif
262 }
263
264 static target_ulong arm_semi_syscall_len;
265
266 static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
267 {
268 ARMCPU *cpu = ARM_CPU(cs);
269 CPUARMState *env = &cpu->env;
270 target_ulong reg0 = is_a64(env) ? env->xregs[0] : env->regs[0];
271
272 if (ret == (target_ulong)-1) {
273 errno = err;
274 set_swi_errno(env, -1);
275 reg0 = ret;
276 } else {
277 /* Fixup syscalls that use nonstardard return conventions. */
278 switch (reg0) {
279 case TARGET_SYS_WRITE:
280 case TARGET_SYS_READ:
281 reg0 = arm_semi_syscall_len - ret;
282 break;
283 case TARGET_SYS_SEEK:
284 reg0 = 0;
285 break;
286 default:
287 reg0 = ret;
288 break;
289 }
290 }
291 if (is_a64(env)) {
292 env->xregs[0] = reg0;
293 } else {
294 env->regs[0] = reg0;
295 }
296 }
297
298 static target_ulong arm_flen_buf(ARMCPU *cpu)
299 {
300 /* Return an address in target memory of 64 bytes where the remote
301 * gdb should write its stat struct. (The format of this structure
302 * is defined by GDB's remote protocol and is not target-specific.)
303 * We put this on the guest's stack just below SP.
304 */
305 CPUARMState *env = &cpu->env;
306 target_ulong sp;
307
308 if (is_a64(env)) {
309 sp = env->xregs[31];
310 } else {
311 sp = env->regs[13];
312 }
313
314 return sp - 64;
315 }
316
317 static void arm_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err)
318 {
319 ARMCPU *cpu = ARM_CPU(cs);
320 CPUARMState *env = &cpu->env;
321 /* The size is always stored in big-endian order, extract
322 the value. We assume the size always fit in 32 bits. */
323 uint32_t size;
324 cpu_memory_rw_debug(cs, arm_flen_buf(cpu) + 32, (uint8_t *)&size, 4, 0);
325 size = be32_to_cpu(size);
326 if (is_a64(env)) {
327 env->xregs[0] = size;
328 } else {
329 env->regs[0] = size;
330 }
331 errno = err;
332 set_swi_errno(env, -1);
333 }
334
335 static int arm_semi_open_guestfd;
336
337 static void arm_semi_open_cb(CPUState *cs, target_ulong ret, target_ulong err)
338 {
339 ARMCPU *cpu = ARM_CPU(cs);
340 CPUARMState *env = &cpu->env;
341 if (ret == (target_ulong)-1) {
342 errno = err;
343 set_swi_errno(env, -1);
344 dealloc_guestfd(arm_semi_open_guestfd);
345 } else {
346 associate_guestfd(arm_semi_open_guestfd, ret);
347 ret = arm_semi_open_guestfd;
348 }
349
350 if (is_a64(env)) {
351 env->xregs[0] = ret;
352 } else {
353 env->regs[0] = ret;
354 }
355 }
356
357 static target_ulong arm_gdb_syscall(ARMCPU *cpu, gdb_syscall_complete_cb cb,
358 const char *fmt, ...)
359 {
360 va_list va;
361 CPUARMState *env = &cpu->env;
362
363 va_start(va, fmt);
364 gdb_do_syscallv(cb, fmt, va);
365 va_end(va);
366
367 /*
368 * FIXME: in softmmu mode, the gdbstub will schedule our callback
369 * to occur, but will not actually call it to complete the syscall
370 * until after this function has returned and we are back in the
371 * CPU main loop. Therefore callers to this function must not
372 * do anything with its return value, because it is not necessarily
373 * the result of the syscall, but could just be the old value of X0.
374 * The only thing safe to do with this is that the callers of
375 * do_arm_semihosting() will write it straight back into X0.
376 * (In linux-user mode, the callback will have happened before
377 * gdb_do_syscallv() returns.)
378 *
379 * We should tidy this up so neither this function nor
380 * do_arm_semihosting() return a value, so the mistake of
381 * doing something with the return value is not possible to make.
382 */
383
384 return is_a64(env) ? env->xregs[0] : env->regs[0];
385 }
386
387 /*
388 * Types for functions implementing various semihosting calls
389 * for specific types of guest file descriptor. These must all
390 * do the work and return the required return value for the guest,
391 * setting the guest errno if appropriate.
392 */
393 typedef uint32_t sys_closefn(ARMCPU *cpu, GuestFD *gf);
394 typedef uint32_t sys_writefn(ARMCPU *cpu, GuestFD *gf,
395 target_ulong buf, uint32_t len);
396 typedef uint32_t sys_readfn(ARMCPU *cpu, GuestFD *gf,
397 target_ulong buf, uint32_t len);
398 typedef uint32_t sys_isattyfn(ARMCPU *cpu, GuestFD *gf);
399 typedef uint32_t sys_seekfn(ARMCPU *cpu, GuestFD *gf,
400 target_ulong offset);
401 typedef uint32_t sys_flenfn(ARMCPU *cpu, GuestFD *gf);
402
403 static uint32_t host_closefn(ARMCPU *cpu, GuestFD *gf)
404 {
405 CPUARMState *env = &cpu->env;
406
407 /*
408 * Only close the underlying host fd if it's one we opened on behalf
409 * of the guest in SYS_OPEN.
410 */
411 if (gf->hostfd == STDIN_FILENO ||
412 gf->hostfd == STDOUT_FILENO ||
413 gf->hostfd == STDERR_FILENO) {
414 return 0;
415 }
416 return set_swi_errno(env, close(gf->hostfd));
417 }
418
419 static uint32_t host_writefn(ARMCPU *cpu, GuestFD *gf,
420 target_ulong buf, uint32_t len)
421 {
422 uint32_t ret;
423 CPUARMState *env = &cpu->env;
424 char *s = lock_user(VERIFY_READ, buf, len, 1);
425 if (!s) {
426 /* Return bytes not written on error */
427 return len;
428 }
429 ret = set_swi_errno(env, write(gf->hostfd, s, len));
430 unlock_user(s, buf, 0);
431 if (ret == (uint32_t)-1) {
432 ret = 0;
433 }
434 /* Return bytes not written */
435 return len - ret;
436 }
437
438 static uint32_t host_readfn(ARMCPU *cpu, GuestFD *gf,
439 target_ulong buf, uint32_t len)
440 {
441 uint32_t ret;
442 CPUARMState *env = &cpu->env;
443 char *s = lock_user(VERIFY_WRITE, buf, len, 0);
444 if (!s) {
445 /* return bytes not read */
446 return len;
447 }
448 do {
449 ret = set_swi_errno(env, read(gf->hostfd, s, len));
450 } while (ret == -1 && errno == EINTR);
451 unlock_user(s, buf, len);
452 if (ret == (uint32_t)-1) {
453 ret = 0;
454 }
455 /* Return bytes not read */
456 return len - ret;
457 }
458
459 static uint32_t host_isattyfn(ARMCPU *cpu, GuestFD *gf)
460 {
461 return isatty(gf->hostfd);
462 }
463
464 static uint32_t host_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
465 {
466 CPUARMState *env = &cpu->env;
467 uint32_t ret = set_swi_errno(env, lseek(gf->hostfd, offset, SEEK_SET));
468 if (ret == (uint32_t)-1) {
469 return -1;
470 }
471 return 0;
472 }
473
474 static uint32_t host_flenfn(ARMCPU *cpu, GuestFD *gf)
475 {
476 CPUARMState *env = &cpu->env;
477 struct stat buf;
478 uint32_t ret = set_swi_errno(env, fstat(gf->hostfd, &buf));
479 if (ret == (uint32_t)-1) {
480 return -1;
481 }
482 return buf.st_size;
483 }
484
485 static uint32_t gdb_closefn(ARMCPU *cpu, GuestFD *gf)
486 {
487 return arm_gdb_syscall(cpu, arm_semi_cb, "close,%x", gf->hostfd);
488 }
489
490 static uint32_t gdb_writefn(ARMCPU *cpu, GuestFD *gf,
491 target_ulong buf, uint32_t len)
492 {
493 arm_semi_syscall_len = len;
494 return arm_gdb_syscall(cpu, arm_semi_cb, "write,%x,%x,%x",
495 gf->hostfd, buf, len);
496 }
497
498 static uint32_t gdb_readfn(ARMCPU *cpu, GuestFD *gf,
499 target_ulong buf, uint32_t len)
500 {
501 arm_semi_syscall_len = len;
502 return arm_gdb_syscall(cpu, arm_semi_cb, "read,%x,%x,%x",
503 gf->hostfd, buf, len);
504 }
505
506 static uint32_t gdb_isattyfn(ARMCPU *cpu, GuestFD *gf)
507 {
508 return arm_gdb_syscall(cpu, arm_semi_cb, "isatty,%x", gf->hostfd);
509 }
510
511 static uint32_t gdb_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
512 {
513 return arm_gdb_syscall(cpu, arm_semi_cb, "lseek,%x,%x,0",
514 gf->hostfd, offset);
515 }
516
517 static uint32_t gdb_flenfn(ARMCPU *cpu, GuestFD *gf)
518 {
519 return arm_gdb_syscall(cpu, arm_semi_flen_cb, "fstat,%x,%x",
520 gf->hostfd, arm_flen_buf(cpu));
521 }
522
523 #define SHFB_MAGIC_0 0x53
524 #define SHFB_MAGIC_1 0x48
525 #define SHFB_MAGIC_2 0x46
526 #define SHFB_MAGIC_3 0x42
527
528 /* Feature bits reportable in feature byte 0 */
529 #define SH_EXT_EXIT_EXTENDED (1 << 0)
530 #define SH_EXT_STDOUT_STDERR (1 << 1)
531
532 static const uint8_t featurefile_data[] = {
533 SHFB_MAGIC_0,
534 SHFB_MAGIC_1,
535 SHFB_MAGIC_2,
536 SHFB_MAGIC_3,
537 SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
538 };
539
540 static void init_featurefile_guestfd(int guestfd)
541 {
542 GuestFD *gf = do_get_guestfd(guestfd);
543
544 assert(gf);
545 gf->type = GuestFDFeatureFile;
546 gf->featurefile_offset = 0;
547 }
548
549 static uint32_t featurefile_closefn(ARMCPU *cpu, GuestFD *gf)
550 {
551 /* Nothing to do */
552 return 0;
553 }
554
555 static uint32_t featurefile_writefn(ARMCPU *cpu, GuestFD *gf,
556 target_ulong buf, uint32_t len)
557 {
558 /* This fd can never be open for writing */
559 CPUARMState *env = &cpu->env;
560
561 errno = EBADF;
562 return set_swi_errno(env, -1);
563 }
564
565 static uint32_t featurefile_readfn(ARMCPU *cpu, GuestFD *gf,
566 target_ulong buf, uint32_t len)
567 {
568 uint32_t i;
569 #ifndef CONFIG_USER_ONLY
570 CPUARMState *env = &cpu->env;
571 #endif
572 char *s;
573
574 s = lock_user(VERIFY_WRITE, buf, len, 0);
575 if (!s) {
576 return len;
577 }
578
579 for (i = 0; i < len; i++) {
580 if (gf->featurefile_offset >= sizeof(featurefile_data)) {
581 break;
582 }
583 s[i] = featurefile_data[gf->featurefile_offset];
584 gf->featurefile_offset++;
585 }
586
587 unlock_user(s, buf, len);
588
589 /* Return number of bytes not read */
590 return len - i;
591 }
592
593 static uint32_t featurefile_isattyfn(ARMCPU *cpu, GuestFD *gf)
594 {
595 return 0;
596 }
597
598 static uint32_t featurefile_seekfn(ARMCPU *cpu, GuestFD *gf,
599 target_ulong offset)
600 {
601 gf->featurefile_offset = offset;
602 return 0;
603 }
604
605 static uint32_t featurefile_flenfn(ARMCPU *cpu, GuestFD *gf)
606 {
607 return sizeof(featurefile_data);
608 }
609
610 typedef struct GuestFDFunctions {
611 sys_closefn *closefn;
612 sys_writefn *writefn;
613 sys_readfn *readfn;
614 sys_isattyfn *isattyfn;
615 sys_seekfn *seekfn;
616 sys_flenfn *flenfn;
617 } GuestFDFunctions;
618
619 static const GuestFDFunctions guestfd_fns[] = {
620 [GuestFDHost] = {
621 .closefn = host_closefn,
622 .writefn = host_writefn,
623 .readfn = host_readfn,
624 .isattyfn = host_isattyfn,
625 .seekfn = host_seekfn,
626 .flenfn = host_flenfn,
627 },
628 [GuestFDGDB] = {
629 .closefn = gdb_closefn,
630 .writefn = gdb_writefn,
631 .readfn = gdb_readfn,
632 .isattyfn = gdb_isattyfn,
633 .seekfn = gdb_seekfn,
634 .flenfn = gdb_flenfn,
635 },
636 [GuestFDFeatureFile] = {
637 .closefn = featurefile_closefn,
638 .writefn = featurefile_writefn,
639 .readfn = featurefile_readfn,
640 .isattyfn = featurefile_isattyfn,
641 .seekfn = featurefile_seekfn,
642 .flenfn = featurefile_flenfn,
643 },
644 };
645
646 /* Read the input value from the argument block; fail the semihosting
647 * call if the memory read fails.
648 */
649 #define GET_ARG(n) do { \
650 if (is_a64(env)) { \
651 if (get_user_u64(arg ## n, args + (n) * 8)) { \
652 errno = EFAULT; \
653 return set_swi_errno(env, -1); \
654 } \
655 } else { \
656 if (get_user_u32(arg ## n, args + (n) * 4)) { \
657 errno = EFAULT; \
658 return set_swi_errno(env, -1); \
659 } \
660 } \
661 } while (0)
662
663 #define SET_ARG(n, val) \
664 (is_a64(env) ? \
665 put_user_u64(val, args + (n) * 8) : \
666 put_user_u32(val, args + (n) * 4))
667
668 /*
669 * Do a semihosting call.
670 *
671 * The specification always says that the "return register" either
672 * returns a specific value or is corrupted, so we don't need to
673 * report to our caller whether we are returning a value or trying to
674 * leave the register unchanged. We use 0xdeadbeef as the return value
675 * when there isn't a defined return value for the call.
676 */
677 target_ulong do_arm_semihosting(CPUARMState *env)
678 {
679 ARMCPU *cpu = env_archcpu(env);
680 CPUState *cs = env_cpu(env);
681 target_ulong args;
682 target_ulong arg0, arg1, arg2, arg3;
683 char * s;
684 int nr;
685 uint32_t ret;
686 uint32_t len;
687 GuestFD *gf;
688
689 if (is_a64(env)) {
690 /* Note that the syscall number is in W0, not X0 */
691 nr = env->xregs[0] & 0xffffffffU;
692 args = env->xregs[1];
693 } else {
694 nr = env->regs[0];
695 args = env->regs[1];
696 }
697
698 switch (nr) {
699 case TARGET_SYS_OPEN:
700 {
701 int guestfd;
702
703 GET_ARG(0);
704 GET_ARG(1);
705 GET_ARG(2);
706 s = lock_user_string(arg0);
707 if (!s) {
708 errno = EFAULT;
709 return set_swi_errno(env, -1);
710 }
711 if (arg1 >= 12) {
712 unlock_user(s, arg0, 0);
713 errno = EINVAL;
714 return set_swi_errno(env, -1);
715 }
716
717 guestfd = alloc_guestfd();
718 if (guestfd < 0) {
719 unlock_user(s, arg0, 0);
720 errno = EMFILE;
721 return set_swi_errno(env, -1);
722 }
723
724 if (strcmp(s, ":tt") == 0) {
725 int result_fileno;
726
727 /*
728 * We implement SH_EXT_STDOUT_STDERR, so:
729 * open for read == stdin
730 * open for write == stdout
731 * open for append == stderr
732 */
733 if (arg1 < 4) {
734 result_fileno = STDIN_FILENO;
735 } else if (arg1 < 8) {
736 result_fileno = STDOUT_FILENO;
737 } else {
738 result_fileno = STDERR_FILENO;
739 }
740 associate_guestfd(guestfd, result_fileno);
741 unlock_user(s, arg0, 0);
742 return guestfd;
743 }
744 if (strcmp(s, ":semihosting-features") == 0) {
745 unlock_user(s, arg0, 0);
746 /* We must fail opens for modes other than 0 ('r') or 1 ('rb') */
747 if (arg1 != 0 && arg1 != 1) {
748 dealloc_guestfd(guestfd);
749 errno = EACCES;
750 return set_swi_errno(env, -1);
751 }
752 init_featurefile_guestfd(guestfd);
753 return guestfd;
754 }
755
756 if (use_gdb_syscalls()) {
757 arm_semi_open_guestfd = guestfd;
758 ret = arm_gdb_syscall(cpu, arm_semi_open_cb, "open,%s,%x,1a4", arg0,
759 (int)arg2 + 1, gdb_open_modeflags[arg1]);
760 } else {
761 ret = set_swi_errno(env, open(s, open_modeflags[arg1], 0644));
762 if (ret == (uint32_t)-1) {
763 dealloc_guestfd(guestfd);
764 } else {
765 associate_guestfd(guestfd, ret);
766 ret = guestfd;
767 }
768 }
769 unlock_user(s, arg0, 0);
770 return ret;
771 }
772 case TARGET_SYS_CLOSE:
773 GET_ARG(0);
774
775 gf = get_guestfd(arg0);
776 if (!gf) {
777 errno = EBADF;
778 return set_swi_errno(env, -1);
779 }
780
781 ret = guestfd_fns[gf->type].closefn(cpu, gf);
782 dealloc_guestfd(arg0);
783 return ret;
784 case TARGET_SYS_WRITEC:
785 qemu_semihosting_console_outc(env, args);
786 return 0xdeadbeef;
787 case TARGET_SYS_WRITE0:
788 return qemu_semihosting_console_outs(env, args);
789 case TARGET_SYS_WRITE:
790 GET_ARG(0);
791 GET_ARG(1);
792 GET_ARG(2);
793 len = arg2;
794
795 gf = get_guestfd(arg0);
796 if (!gf) {
797 errno = EBADF;
798 return set_swi_errno(env, -1);
799 }
800
801 return guestfd_fns[gf->type].writefn(cpu, gf, arg1, len);
802 case TARGET_SYS_READ:
803 GET_ARG(0);
804 GET_ARG(1);
805 GET_ARG(2);
806 len = arg2;
807
808 gf = get_guestfd(arg0);
809 if (!gf) {
810 errno = EBADF;
811 return set_swi_errno(env, -1);
812 }
813
814 return guestfd_fns[gf->type].readfn(cpu, gf, arg1, len);
815 case TARGET_SYS_READC:
816 return qemu_semihosting_console_inc(env);
817 case TARGET_SYS_ISTTY:
818 GET_ARG(0);
819
820 gf = get_guestfd(arg0);
821 if (!gf) {
822 errno = EBADF;
823 return set_swi_errno(env, -1);
824 }
825
826 return guestfd_fns[gf->type].isattyfn(cpu, gf);
827 case TARGET_SYS_SEEK:
828 GET_ARG(0);
829 GET_ARG(1);
830
831 gf = get_guestfd(arg0);
832 if (!gf) {
833 errno = EBADF;
834 return set_swi_errno(env, -1);
835 }
836
837 return guestfd_fns[gf->type].seekfn(cpu, gf, arg1);
838 case TARGET_SYS_FLEN:
839 GET_ARG(0);
840
841 gf = get_guestfd(arg0);
842 if (!gf) {
843 errno = EBADF;
844 return set_swi_errno(env, -1);
845 }
846
847 return guestfd_fns[gf->type].flenfn(cpu, gf);
848 case TARGET_SYS_TMPNAM:
849 qemu_log_mask(LOG_UNIMP, "%s: SYS_TMPNAM not implemented", __func__);
850 return -1;
851 case TARGET_SYS_REMOVE:
852 GET_ARG(0);
853 GET_ARG(1);
854 if (use_gdb_syscalls()) {
855 ret = arm_gdb_syscall(cpu, arm_semi_cb, "unlink,%s",
856 arg0, (int)arg1 + 1);
857 } else {
858 s = lock_user_string(arg0);
859 if (!s) {
860 errno = EFAULT;
861 return set_swi_errno(env, -1);
862 }
863 ret = set_swi_errno(env, remove(s));
864 unlock_user(s, arg0, 0);
865 }
866 return ret;
867 case TARGET_SYS_RENAME:
868 GET_ARG(0);
869 GET_ARG(1);
870 GET_ARG(2);
871 GET_ARG(3);
872 if (use_gdb_syscalls()) {
873 return arm_gdb_syscall(cpu, arm_semi_cb, "rename,%s,%s",
874 arg0, (int)arg1 + 1, arg2, (int)arg3 + 1);
875 } else {
876 char *s2;
877 s = lock_user_string(arg0);
878 s2 = lock_user_string(arg2);
879 if (!s || !s2) {
880 errno = EFAULT;
881 ret = set_swi_errno(env, -1);
882 } else {
883 ret = set_swi_errno(env, rename(s, s2));
884 }
885 if (s2)
886 unlock_user(s2, arg2, 0);
887 if (s)
888 unlock_user(s, arg0, 0);
889 return ret;
890 }
891 case TARGET_SYS_CLOCK:
892 return clock() / (CLOCKS_PER_SEC / 100);
893 case TARGET_SYS_TIME:
894 return set_swi_errno(env, time(NULL));
895 case TARGET_SYS_SYSTEM:
896 GET_ARG(0);
897 GET_ARG(1);
898 if (use_gdb_syscalls()) {
899 return arm_gdb_syscall(cpu, arm_semi_cb, "system,%s",
900 arg0, (int)arg1 + 1);
901 } else {
902 s = lock_user_string(arg0);
903 if (!s) {
904 errno = EFAULT;
905 return set_swi_errno(env, -1);
906 }
907 ret = set_swi_errno(env, system(s));
908 unlock_user(s, arg0, 0);
909 return ret;
910 }
911 case TARGET_SYS_ERRNO:
912 return get_swi_errno(env);
913 case TARGET_SYS_GET_CMDLINE:
914 {
915 /* Build a command-line from the original argv.
916 *
917 * The inputs are:
918 * * arg0, pointer to a buffer of at least the size
919 * specified in arg1.
920 * * arg1, size of the buffer pointed to by arg0 in
921 * bytes.
922 *
923 * The outputs are:
924 * * arg0, pointer to null-terminated string of the
925 * command line.
926 * * arg1, length of the string pointed to by arg0.
927 */
928
929 char *output_buffer;
930 size_t input_size;
931 size_t output_size;
932 int status = 0;
933 #if !defined(CONFIG_USER_ONLY)
934 const char *cmdline;
935 #else
936 TaskState *ts = cs->opaque;
937 #endif
938 GET_ARG(0);
939 GET_ARG(1);
940 input_size = arg1;
941 /* Compute the size of the output string. */
942 #if !defined(CONFIG_USER_ONLY)
943 cmdline = semihosting_get_cmdline();
944 if (cmdline == NULL) {
945 cmdline = ""; /* Default to an empty line. */
946 }
947 output_size = strlen(cmdline) + 1; /* Count terminating 0. */
948 #else
949 unsigned int i;
950
951 output_size = ts->info->arg_end - ts->info->arg_start;
952 if (!output_size) {
953 /*
954 * We special-case the "empty command line" case (argc==0).
955 * Just provide the terminating 0.
956 */
957 output_size = 1;
958 }
959 #endif
960
961 if (output_size > input_size) {
962 /* Not enough space to store command-line arguments. */
963 errno = E2BIG;
964 return set_swi_errno(env, -1);
965 }
966
967 /* Adjust the command-line length. */
968 if (SET_ARG(1, output_size - 1)) {
969 /* Couldn't write back to argument block */
970 errno = EFAULT;
971 return set_swi_errno(env, -1);
972 }
973
974 /* Lock the buffer on the ARM side. */
975 output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
976 if (!output_buffer) {
977 errno = EFAULT;
978 return set_swi_errno(env, -1);
979 }
980
981 /* Copy the command-line arguments. */
982 #if !defined(CONFIG_USER_ONLY)
983 pstrcpy(output_buffer, output_size, cmdline);
984 #else
985 if (output_size == 1) {
986 /* Empty command-line. */
987 output_buffer[0] = '\0';
988 goto out;
989 }
990
991 if (copy_from_user(output_buffer, ts->info->arg_start,
992 output_size)) {
993 errno = EFAULT;
994 status = set_swi_errno(env, -1);
995 goto out;
996 }
997
998 /* Separate arguments by white spaces. */
999 for (i = 0; i < output_size - 1; i++) {
1000 if (output_buffer[i] == 0) {
1001 output_buffer[i] = ' ';
1002 }
1003 }
1004 out:
1005 #endif
1006 /* Unlock the buffer on the ARM side. */
1007 unlock_user(output_buffer, arg0, output_size);
1008
1009 return status;
1010 }
1011 case TARGET_SYS_HEAPINFO:
1012 {
1013 target_ulong retvals[4];
1014 target_ulong limit;
1015 int i;
1016 #ifdef CONFIG_USER_ONLY
1017 TaskState *ts = cs->opaque;
1018 #else
1019 const struct arm_boot_info *info = env->boot_info;
1020 target_ulong rambase = info->loader_start;
1021 #endif
1022
1023 GET_ARG(0);
1024
1025 #ifdef CONFIG_USER_ONLY
1026 /*
1027 * Some C libraries assume the heap immediately follows .bss, so
1028 * allocate it using sbrk.
1029 */
1030 if (!ts->heap_limit) {
1031 abi_ulong ret;
1032
1033 ts->heap_base = do_brk(0);
1034 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
1035 /* Try a big heap, and reduce the size if that fails. */
1036 for (;;) {
1037 ret = do_brk(limit);
1038 if (ret >= limit) {
1039 break;
1040 }
1041 limit = (ts->heap_base >> 1) + (limit >> 1);
1042 }
1043 ts->heap_limit = limit;
1044 }
1045
1046 retvals[0] = ts->heap_base;
1047 retvals[1] = ts->heap_limit;
1048 retvals[2] = ts->stack_base;
1049 retvals[3] = 0; /* Stack limit. */
1050 #else
1051 limit = ram_size;
1052 /* TODO: Make this use the limit of the loaded application. */
1053 retvals[0] = rambase + limit / 2;
1054 retvals[1] = rambase + limit;
1055 retvals[2] = rambase + limit; /* Stack base */
1056 retvals[3] = rambase; /* Stack limit. */
1057 #endif
1058
1059 for (i = 0; i < ARRAY_SIZE(retvals); i++) {
1060 bool fail;
1061
1062 if (is_a64(env)) {
1063 fail = put_user_u64(retvals[i], arg0 + i * 8);
1064 } else {
1065 fail = put_user_u32(retvals[i], arg0 + i * 4);
1066 }
1067
1068 if (fail) {
1069 /* Couldn't write back to argument block */
1070 errno = EFAULT;
1071 return set_swi_errno(env, -1);
1072 }
1073 }
1074 return 0;
1075 }
1076 case TARGET_SYS_EXIT:
1077 case TARGET_SYS_EXIT_EXTENDED:
1078 if (nr == TARGET_SYS_EXIT_EXTENDED || is_a64(env)) {
1079 /*
1080 * The A64 version of SYS_EXIT takes a parameter block,
1081 * so the application-exit type can return a subcode which
1082 * is the exit status code from the application.
1083 * SYS_EXIT_EXTENDED is an a new-in-v2.0 optional function
1084 * which allows A32/T32 guests to also provide a status code.
1085 */
1086 GET_ARG(0);
1087 GET_ARG(1);
1088
1089 if (arg0 == ADP_Stopped_ApplicationExit) {
1090 ret = arg1;
1091 } else {
1092 ret = 1;
1093 }
1094 } else {
1095 /*
1096 * The A32/T32 version of SYS_EXIT specifies only
1097 * Stopped_ApplicationExit as normal exit, but does not
1098 * allow the guest to specify the exit status code.
1099 * Everything else is considered an error.
1100 */
1101 ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
1102 }
1103 gdb_exit(env, ret);
1104 exit(ret);
1105 case TARGET_SYS_SYNCCACHE:
1106 /*
1107 * Clean the D-cache and invalidate the I-cache for the specified
1108 * virtual address range. This is a nop for us since we don't
1109 * implement caches. This is only present on A64.
1110 */
1111 if (is_a64(env)) {
1112 return 0;
1113 }
1114 /* fall through -- invalid for A32/T32 */
1115 default:
1116 fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
1117 cpu_dump_state(cs, stderr, 0);
1118 abort();
1119 }
1120 }