xref: /openbmc/qemu/cpu-target.c (revision cde3c425)
1 /*
2  * Target-specific parts of the CPU object
3  *
4  *  Copyright (c) 2003 Fabrice Bellard
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qapi/error.h"
22 
23 #include "exec/target_page.h"
24 #include "exec/page-protection.h"
25 #include "hw/qdev-core.h"
26 #include "hw/qdev-properties.h"
27 #include "qemu/error-report.h"
28 #include "qemu/qemu-print.h"
29 #include "migration/vmstate.h"
30 #ifdef CONFIG_USER_ONLY
31 #include "qemu.h"
32 #else
33 #include "hw/core/sysemu-cpu-ops.h"
34 #include "exec/address-spaces.h"
35 #include "exec/memory.h"
36 #endif
37 #include "sysemu/cpus.h"
38 #include "sysemu/tcg.h"
39 #include "exec/tswap.h"
40 #include "exec/replay-core.h"
41 #include "exec/cpu-common.h"
42 #include "exec/exec-all.h"
43 #include "exec/tb-flush.h"
44 #include "exec/translate-all.h"
45 #include "exec/log.h"
46 #include "hw/core/accel-cpu.h"
47 #include "trace/trace-root.h"
48 #include "qemu/accel.h"
49 
50 #ifndef CONFIG_USER_ONLY
51 static int cpu_common_post_load(void *opaque, int version_id)
52 {
53     CPUState *cpu = opaque;
54 
55     /* 0x01 was CPU_INTERRUPT_EXIT. This line can be removed when the
56        version_id is increased. */
57     cpu->interrupt_request &= ~0x01;
58     tlb_flush(cpu);
59 
60     /* loadvm has just updated the content of RAM, bypassing the
61      * usual mechanisms that ensure we flush TBs for writes to
62      * memory we've translated code from. So we must flush all TBs,
63      * which will now be stale.
64      */
65     tb_flush(cpu);
66 
67     return 0;
68 }
69 
70 static int cpu_common_pre_load(void *opaque)
71 {
72     CPUState *cpu = opaque;
73 
74     cpu->exception_index = -1;
75 
76     return 0;
77 }
78 
79 static bool cpu_common_exception_index_needed(void *opaque)
80 {
81     CPUState *cpu = opaque;
82 
83     return tcg_enabled() && cpu->exception_index != -1;
84 }
85 
86 static const VMStateDescription vmstate_cpu_common_exception_index = {
87     .name = "cpu_common/exception_index",
88     .version_id = 1,
89     .minimum_version_id = 1,
90     .needed = cpu_common_exception_index_needed,
91     .fields = (const VMStateField[]) {
92         VMSTATE_INT32(exception_index, CPUState),
93         VMSTATE_END_OF_LIST()
94     }
95 };
96 
97 static bool cpu_common_crash_occurred_needed(void *opaque)
98 {
99     CPUState *cpu = opaque;
100 
101     return cpu->crash_occurred;
102 }
103 
104 static const VMStateDescription vmstate_cpu_common_crash_occurred = {
105     .name = "cpu_common/crash_occurred",
106     .version_id = 1,
107     .minimum_version_id = 1,
108     .needed = cpu_common_crash_occurred_needed,
109     .fields = (const VMStateField[]) {
110         VMSTATE_BOOL(crash_occurred, CPUState),
111         VMSTATE_END_OF_LIST()
112     }
113 };
114 
115 const VMStateDescription vmstate_cpu_common = {
116     .name = "cpu_common",
117     .version_id = 1,
118     .minimum_version_id = 1,
119     .pre_load = cpu_common_pre_load,
120     .post_load = cpu_common_post_load,
121     .fields = (const VMStateField[]) {
122         VMSTATE_UINT32(halted, CPUState),
123         VMSTATE_UINT32(interrupt_request, CPUState),
124         VMSTATE_END_OF_LIST()
125     },
126     .subsections = (const VMStateDescription * const []) {
127         &vmstate_cpu_common_exception_index,
128         &vmstate_cpu_common_crash_occurred,
129         NULL
130     }
131 };
132 #endif
133 
134 bool cpu_exec_realizefn(CPUState *cpu, Error **errp)
135 {
136     /* cache the cpu class for the hotpath */
137     cpu->cc = CPU_GET_CLASS(cpu);
138 
139     if (!accel_cpu_common_realize(cpu, errp)) {
140         return false;
141     }
142 
143     /* Wait until cpu initialization complete before exposing cpu. */
144     cpu_list_add(cpu);
145 
146 #ifdef CONFIG_USER_ONLY
147     assert(qdev_get_vmsd(DEVICE(cpu)) == NULL ||
148            qdev_get_vmsd(DEVICE(cpu))->unmigratable);
149 #else
150     if (qdev_get_vmsd(DEVICE(cpu)) == NULL) {
151         vmstate_register(NULL, cpu->cpu_index, &vmstate_cpu_common, cpu);
152     }
153     if (cpu->cc->sysemu_ops->legacy_vmsd != NULL) {
154         vmstate_register(NULL, cpu->cpu_index, cpu->cc->sysemu_ops->legacy_vmsd, cpu);
155     }
156 #endif /* CONFIG_USER_ONLY */
157 
158     return true;
159 }
160 
161 void cpu_exec_unrealizefn(CPUState *cpu)
162 {
163 #ifndef CONFIG_USER_ONLY
164     CPUClass *cc = CPU_GET_CLASS(cpu);
165 
166     if (cc->sysemu_ops->legacy_vmsd != NULL) {
167         vmstate_unregister(NULL, cc->sysemu_ops->legacy_vmsd, cpu);
168     }
169     if (qdev_get_vmsd(DEVICE(cpu)) == NULL) {
170         vmstate_unregister(NULL, &vmstate_cpu_common, cpu);
171     }
172 #endif
173 
174     cpu_list_remove(cpu);
175     /*
176      * Now that the vCPU has been removed from the RCU list, we can call
177      * accel_cpu_common_unrealize, which may free fields using call_rcu.
178      */
179     accel_cpu_common_unrealize(cpu);
180 }
181 
182 /*
183  * This can't go in hw/core/cpu.c because that file is compiled only
184  * once for both user-mode and system builds.
185  */
186 static Property cpu_common_props[] = {
187 #ifdef CONFIG_USER_ONLY
188     /*
189      * Create a property for the user-only object, so users can
190      * adjust prctl(PR_SET_UNALIGN) from the command-line.
191      * Has no effect if the target does not support the feature.
192      */
193     DEFINE_PROP_BOOL("prctl-unalign-sigbus", CPUState,
194                      prctl_unalign_sigbus, false),
195 #else
196     /*
197      * Create a memory property for system CPU object, so users can
198      * wire up its memory.  The default if no link is set up is to use
199      * the system address space.
200      */
201     DEFINE_PROP_LINK("memory", CPUState, memory, TYPE_MEMORY_REGION,
202                      MemoryRegion *),
203 #endif
204     DEFINE_PROP_END_OF_LIST(),
205 };
206 
207 #ifndef CONFIG_USER_ONLY
208 static bool cpu_get_start_powered_off(Object *obj, Error **errp)
209 {
210     CPUState *cpu = CPU(obj);
211     return cpu->start_powered_off;
212 }
213 
214 static void cpu_set_start_powered_off(Object *obj, bool value, Error **errp)
215 {
216     CPUState *cpu = CPU(obj);
217     cpu->start_powered_off = value;
218 }
219 #endif
220 
221 void cpu_class_init_props(DeviceClass *dc)
222 {
223 #ifndef CONFIG_USER_ONLY
224     ObjectClass *oc = OBJECT_CLASS(dc);
225 
226     /*
227      * We can't use DEFINE_PROP_BOOL in the Property array for this
228      * property, because we want this to be settable after realize.
229      */
230     object_class_property_add_bool(oc, "start-powered-off",
231                                    cpu_get_start_powered_off,
232                                    cpu_set_start_powered_off);
233 #endif
234 
235     device_class_set_props(dc, cpu_common_props);
236 }
237 
238 void cpu_exec_initfn(CPUState *cpu)
239 {
240     cpu->as = NULL;
241     cpu->num_ases = 0;
242 
243 #ifndef CONFIG_USER_ONLY
244     cpu->memory = get_system_memory();
245     object_ref(OBJECT(cpu->memory));
246 #endif
247 }
248 
249 char *cpu_model_from_type(const char *typename)
250 {
251     const char *suffix = "-" CPU_RESOLVING_TYPE;
252 
253     if (!object_class_by_name(typename)) {
254         return NULL;
255     }
256 
257     if (g_str_has_suffix(typename, suffix)) {
258         return g_strndup(typename, strlen(typename) - strlen(suffix));
259     }
260 
261     return g_strdup(typename);
262 }
263 
264 const char *parse_cpu_option(const char *cpu_option)
265 {
266     ObjectClass *oc;
267     CPUClass *cc;
268     gchar **model_pieces;
269     const char *cpu_type;
270 
271     model_pieces = g_strsplit(cpu_option, ",", 2);
272     if (!model_pieces[0]) {
273         error_report("-cpu option cannot be empty");
274         exit(1);
275     }
276 
277     oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]);
278     if (oc == NULL) {
279         error_report("unable to find CPU model '%s'", model_pieces[0]);
280         g_strfreev(model_pieces);
281         exit(EXIT_FAILURE);
282     }
283 
284     cpu_type = object_class_get_name(oc);
285     cc = CPU_CLASS(oc);
286     cc->parse_features(cpu_type, model_pieces[1], &error_fatal);
287     g_strfreev(model_pieces);
288     return cpu_type;
289 }
290 
291 #ifndef cpu_list
292 static void cpu_list_entry(gpointer data, gpointer user_data)
293 {
294     CPUClass *cc = CPU_CLASS(OBJECT_CLASS(data));
295     const char *typename = object_class_get_name(OBJECT_CLASS(data));
296     g_autofree char *model = cpu_model_from_type(typename);
297 
298     if (cc->deprecation_note) {
299         qemu_printf("  %s (deprecated)\n", model);
300     } else {
301         qemu_printf("  %s\n", model);
302     }
303 }
304 
305 static void cpu_list(void)
306 {
307     GSList *list;
308 
309     list = object_class_get_list_sorted(TYPE_CPU, false);
310     qemu_printf("Available CPUs:\n");
311     g_slist_foreach(list, cpu_list_entry, NULL);
312     g_slist_free(list);
313 }
314 #endif
315 
316 void list_cpus(void)
317 {
318     cpu_list();
319 }
320 
321 /* enable or disable single step mode. EXCP_DEBUG is returned by the
322    CPU loop after each instruction */
323 void cpu_single_step(CPUState *cpu, int enabled)
324 {
325     if (cpu->singlestep_enabled != enabled) {
326         cpu->singlestep_enabled = enabled;
327 
328 #if !defined(CONFIG_USER_ONLY)
329         const AccelOpsClass *ops = cpus_get_accel();
330         if (ops->update_guest_debug) {
331             ops->update_guest_debug(cpu);
332         }
333 #endif
334 
335         trace_breakpoint_singlestep(cpu->cpu_index, enabled);
336     }
337 }
338 
339 void cpu_abort(CPUState *cpu, const char *fmt, ...)
340 {
341     va_list ap;
342     va_list ap2;
343 
344     va_start(ap, fmt);
345     va_copy(ap2, ap);
346     fprintf(stderr, "qemu: fatal: ");
347     vfprintf(stderr, fmt, ap);
348     fprintf(stderr, "\n");
349     cpu_dump_state(cpu, stderr, CPU_DUMP_FPU | CPU_DUMP_CCOP);
350     if (qemu_log_separate()) {
351         FILE *logfile = qemu_log_trylock();
352         if (logfile) {
353             fprintf(logfile, "qemu: fatal: ");
354             vfprintf(logfile, fmt, ap2);
355             fprintf(logfile, "\n");
356             cpu_dump_state(cpu, logfile, CPU_DUMP_FPU | CPU_DUMP_CCOP);
357             qemu_log_unlock(logfile);
358         }
359     }
360     va_end(ap2);
361     va_end(ap);
362     replay_finish();
363 #if defined(CONFIG_USER_ONLY)
364     {
365         struct sigaction act;
366         sigfillset(&act.sa_mask);
367         act.sa_handler = SIG_DFL;
368         act.sa_flags = 0;
369         sigaction(SIGABRT, &act, NULL);
370     }
371 #endif
372     abort();
373 }
374 
375 /* physical memory access (slow version, mainly for debug) */
376 #if defined(CONFIG_USER_ONLY)
377 int cpu_memory_rw_debug(CPUState *cpu, vaddr addr,
378                         void *ptr, size_t len, bool is_write)
379 {
380     int flags;
381     vaddr l, page;
382     void * p;
383     uint8_t *buf = ptr;
384     ssize_t written;
385     int ret = -1;
386     int fd = -1;
387 
388     while (len > 0) {
389         page = addr & TARGET_PAGE_MASK;
390         l = (page + TARGET_PAGE_SIZE) - addr;
391         if (l > len)
392             l = len;
393         flags = page_get_flags(page);
394         if (!(flags & PAGE_VALID)) {
395             goto out_close;
396         }
397         if (is_write) {
398             if (flags & PAGE_WRITE) {
399                 /* XXX: this code should not depend on lock_user */
400                 p = lock_user(VERIFY_WRITE, addr, l, 0);
401                 if (!p) {
402                     goto out_close;
403                 }
404                 memcpy(p, buf, l);
405                 unlock_user(p, addr, l);
406             } else {
407                 /* Bypass the host page protection using ptrace. */
408                 if (fd == -1) {
409                     fd = open("/proc/self/mem", O_WRONLY);
410                     if (fd == -1) {
411                         goto out;
412                     }
413                 }
414                 /*
415                  * If there is a TranslationBlock and we weren't bypassing the
416                  * host page protection, the memcpy() above would SEGV,
417                  * ultimately leading to page_unprotect(). So invalidate the
418                  * translations manually. Both invalidation and pwrite() must
419                  * be under mmap_lock() in order to prevent the creation of
420                  * another TranslationBlock in between.
421                  */
422                 mmap_lock();
423                 tb_invalidate_phys_range(addr, addr + l - 1);
424                 written = pwrite(fd, buf, l,
425                                  (off_t)(uintptr_t)g2h_untagged(addr));
426                 mmap_unlock();
427                 if (written != l) {
428                     goto out_close;
429                 }
430             }
431         } else if (flags & PAGE_READ) {
432             /* XXX: this code should not depend on lock_user */
433             p = lock_user(VERIFY_READ, addr, l, 1);
434             if (!p) {
435                 goto out_close;
436             }
437             memcpy(buf, p, l);
438             unlock_user(p, addr, 0);
439         } else {
440             /* Bypass the host page protection using ptrace. */
441             if (fd == -1) {
442                 fd = open("/proc/self/mem", O_RDONLY);
443                 if (fd == -1) {
444                     goto out;
445                 }
446             }
447             if (pread(fd, buf, l,
448                       (off_t)(uintptr_t)g2h_untagged(addr)) != l) {
449                 goto out_close;
450             }
451         }
452         len -= l;
453         buf += l;
454         addr += l;
455     }
456     ret = 0;
457 out_close:
458     if (fd != -1) {
459         close(fd);
460     }
461 out:
462     return ret;
463 }
464 #endif
465 
466 bool target_words_bigendian(void)
467 {
468     return TARGET_BIG_ENDIAN;
469 }
470 
471 const char *target_name(void)
472 {
473     return TARGET_NAME;
474 }
475