1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD AND BSD-4-Clause
3 *
4 * Copyright (c) 2010 Justin T. Gibbs, Spectra Logic Corporation
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, and the following disclaimer,
12 * without modification.
13 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14 * substantially similar to the "NO WARRANTY" disclaimer below
15 * ("Disclaimer") and any redistribution must be conditioned upon
16 * including a substantially similar Disclaimer requirement for further
17 * binary redistribution.
18 *
19 * NO WARRANTY
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
28 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGES.
31 */
32
33 /*-
34 * PV suspend/resume support:
35 *
36 * Copyright (c) 2004 Christian Limpach.
37 * Copyright (c) 2004-2006,2008 Kip Macy
38 * All rights reserved.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 3. All advertising materials mentioning features or use of this software
49 * must display the following acknowledgement:
50 * This product includes software developed by Christian Limpach.
51 * 4. The name of the author may not be used to endorse or promote products
52 * derived from this software without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
55 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
56 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
57 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
58 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
59 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
60 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
61 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
62 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
63 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
64 */
65
66 /*-
67 * HVM suspend/resume support:
68 *
69 * Copyright (c) 2008 Citrix Systems, Inc.
70 * All rights reserved.
71 *
72 * Redistribution and use in source and binary forms, with or without
73 * modification, are permitted provided that the following conditions
74 * are met:
75 * 1. Redistributions of source code must retain the above copyright
76 * notice, this list of conditions and the following disclaimer.
77 * 2. Redistributions in binary form must reproduce the above copyright
78 * notice, this list of conditions and the following disclaimer in the
79 * documentation and/or other materials provided with the distribution.
80 *
81 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
82 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
83 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
84 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
85 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
86 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
87 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
88 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
89 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
90 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
91 * SUCH DAMAGE.
92 */
93 #include <sys/cdefs.h>
94 __FBSDID("$FreeBSD$");
95
96 /**
97 * \file control.c
98 *
99 * \brief Device driver to repond to control domain events that impact
100 * this VM.
101 */
102
103 #include <sys/param.h>
104 #include <sys/systm.h>
105 #include <sys/kernel.h>
106 #include <sys/malloc.h>
107
108 #include <sys/bio.h>
109 #include <sys/bus.h>
110 #include <sys/conf.h>
111 #include <sys/disk.h>
112 #include <sys/fcntl.h>
113 #include <sys/filedesc.h>
114 #include <sys/kdb.h>
115 #include <sys/module.h>
116 #include <sys/mount.h>
117 #include <sys/namei.h>
118 #include <sys/proc.h>
119 #include <sys/reboot.h>
120 #include <sys/rman.h>
121 #include <sys/sched.h>
122 #include <sys/taskqueue.h>
123 #include <sys/types.h>
124 #include <sys/vnode.h>
125 #include <sys/sched.h>
126 #include <sys/smp.h>
127 #include <sys/eventhandler.h>
128 #include <sys/timetc.h>
129
130 #include <geom/geom.h>
131
132 #include <machine/_inttypes.h>
133 #include <machine/intr_machdep.h>
134
135 #include <x86/apicvar.h>
136
137 #include <vm/vm.h>
138 #include <vm/vm_extern.h>
139 #include <vm/vm_kern.h>
140
141 #include <xen/xen-os.h>
142 #include <xen/blkif.h>
143 #include <xen/evtchn.h>
144 #include <xen/gnttab.h>
145 #include <xen/xen_intr.h>
146
147 #include <xen/hvm.h>
148
149 #include <xen/interface/event_channel.h>
150 #include <xen/interface/grant_table.h>
151
152 #include <xen/xenbus/xenbusvar.h>
153
154 bool xen_suspend_cancelled;
155 /*--------------------------- Forward Declarations --------------------------*/
156 /** Function signature for shutdown event handlers. */
157 typedef void (xctrl_shutdown_handler_t)(void);
158
159 static xctrl_shutdown_handler_t xctrl_poweroff;
160 static xctrl_shutdown_handler_t xctrl_reboot;
161 static xctrl_shutdown_handler_t xctrl_suspend;
162 static xctrl_shutdown_handler_t xctrl_crash;
163
164 /*-------------------------- Private Data Structures -------------------------*/
165 /** Element type for lookup table of event name to handler. */
166 struct xctrl_shutdown_reason {
167 const char *name;
168 xctrl_shutdown_handler_t *handler;
169 };
170
171 /** Lookup table for shutdown event name to handler. */
172 static const struct xctrl_shutdown_reason xctrl_shutdown_reasons[] = {
173 { "poweroff", xctrl_poweroff },
174 { "reboot", xctrl_reboot },
175 { "suspend", xctrl_suspend },
176 { "crash", xctrl_crash },
177 { "halt", xctrl_poweroff },
178 };
179
180 struct xctrl_softc {
181 struct xs_watch xctrl_watch;
182 };
183
184 /*------------------------------ Event Handlers ------------------------------*/
185 static void
xctrl_poweroff()186 xctrl_poweroff()
187 {
188 shutdown_nice(RB_POWEROFF|RB_HALT);
189 }
190
191 static void
xctrl_reboot()192 xctrl_reboot()
193 {
194 shutdown_nice(0);
195 }
196
197 static void
xctrl_suspend()198 xctrl_suspend()
199 {
200 #ifdef SMP
201 cpuset_t cpu_suspend_map;
202 #endif
203
204 EVENTHANDLER_INVOKE(power_suspend_early);
205 xs_lock();
206 stop_all_proc();
207 xs_unlock();
208 suspend_all_fs();
209 EVENTHANDLER_INVOKE(power_suspend);
210
211 #ifdef EARLY_AP_STARTUP
212 MPASS(mp_ncpus == 1 || smp_started);
213 thread_lock(curthread);
214 sched_bind(curthread, 0);
215 thread_unlock(curthread);
216 #else
217 if (smp_started) {
218 thread_lock(curthread);
219 sched_bind(curthread, 0);
220 thread_unlock(curthread);
221 }
222 #endif
223 KASSERT((PCPU_GET(cpuid) == 0), ("Not running on CPU#0"));
224
225 /*
226 * Be sure to hold Giant across DEVICE_SUSPEND/RESUME since non-MPSAFE
227 * drivers need this.
228 */
229 mtx_lock(&Giant);
230 if (DEVICE_SUSPEND(root_bus) != 0) {
231 mtx_unlock(&Giant);
232 printf("%s: device_suspend failed\n", __func__);
233 return;
234 }
235
236 #ifdef SMP
237 #ifdef EARLY_AP_STARTUP
238 /*
239 * Suspend other CPUs. This prevents IPIs while we
240 * are resuming, and will allow us to reset per-cpu
241 * vcpu_info on resume.
242 */
243 cpu_suspend_map = all_cpus;
244 CPU_CLR(PCPU_GET(cpuid), &cpu_suspend_map);
245 if (!CPU_EMPTY(&cpu_suspend_map))
246 suspend_cpus(cpu_suspend_map);
247 #else
248 CPU_ZERO(&cpu_suspend_map); /* silence gcc */
249 if (smp_started) {
250 /*
251 * Suspend other CPUs. This prevents IPIs while we
252 * are resuming, and will allow us to reset per-cpu
253 * vcpu_info on resume.
254 */
255 cpu_suspend_map = all_cpus;
256 CPU_CLR(PCPU_GET(cpuid), &cpu_suspend_map);
257 if (!CPU_EMPTY(&cpu_suspend_map))
258 suspend_cpus(cpu_suspend_map);
259 }
260 #endif
261 #endif
262
263 /*
264 * Prevent any races with evtchn_interrupt() handler.
265 */
266 disable_intr();
267 intr_suspend();
268 xen_hvm_suspend();
269
270 xen_suspend_cancelled = !!HYPERVISOR_suspend(0);
271
272 if (!xen_suspend_cancelled) {
273 xen_hvm_resume(false);
274 }
275 intr_resume(xen_suspend_cancelled != 0);
276 enable_intr();
277
278 /*
279 * Reset grant table info.
280 */
281 if (!xen_suspend_cancelled) {
282 gnttab_resume(NULL);
283 }
284
285 #ifdef SMP
286 if (!CPU_EMPTY(&cpu_suspend_map)) {
287 /*
288 * Now that event channels have been initialized,
289 * resume CPUs.
290 */
291 resume_cpus(cpu_suspend_map);
292 /* Send an IPI_BITMAP in case there are pending bitmap IPIs. */
293 lapic_ipi_vectored(IPI_BITMAP_VECTOR, APIC_IPI_DEST_ALL);
294 }
295 #endif
296
297 /*
298 * FreeBSD really needs to add DEVICE_SUSPEND_CANCEL or
299 * similar.
300 */
301 DEVICE_RESUME(root_bus);
302 mtx_unlock(&Giant);
303
304 /*
305 * Warm up timecounter again and reset system clock.
306 */
307 timecounter->tc_get_timecount(timecounter);
308 inittodr(time_second);
309
310 #ifdef EARLY_AP_STARTUP
311 thread_lock(curthread);
312 sched_unbind(curthread);
313 thread_unlock(curthread);
314 #else
315 if (smp_started) {
316 thread_lock(curthread);
317 sched_unbind(curthread);
318 thread_unlock(curthread);
319 }
320 #endif
321
322 resume_all_fs();
323 resume_all_proc();
324
325 EVENTHANDLER_INVOKE(power_resume);
326
327 if (bootverbose)
328 printf("System resumed after suspension\n");
329
330 }
331
332 static void
xctrl_crash()333 xctrl_crash()
334 {
335 panic("Xen directed crash");
336 }
337
338 static void
xen_pv_shutdown_final(void * arg,int howto)339 xen_pv_shutdown_final(void *arg, int howto)
340 {
341 /*
342 * Inform the hypervisor that shutdown is complete.
343 * This is not necessary in HVM domains since Xen
344 * emulates ACPI in that mode and FreeBSD's ACPI
345 * support will request this transition.
346 */
347 if (howto & (RB_HALT | RB_POWEROFF))
348 HYPERVISOR_shutdown(SHUTDOWN_poweroff);
349 else
350 HYPERVISOR_shutdown(SHUTDOWN_reboot);
351 }
352
353 /*------------------------------ Event Reception -----------------------------*/
354 static void
xctrl_on_watch_event(struct xs_watch * watch,const char ** vec,unsigned int len)355 xctrl_on_watch_event(struct xs_watch *watch, const char **vec, unsigned int len)
356 {
357 const struct xctrl_shutdown_reason *reason;
358 const struct xctrl_shutdown_reason *last_reason;
359 char *result;
360 int error;
361 int result_len;
362
363 error = xs_read(XST_NIL, "control", "shutdown",
364 &result_len, (void **)&result);
365 if (error != 0 || result_len == 0)
366 return;
367
368 /* Acknowledge the request by writing back an empty string. */
369 error = xs_write(XST_NIL, "control", "shutdown", "");
370 if (error != 0)
371 printf("unable to ack shutdown request, proceeding anyway\n");
372
373 reason = xctrl_shutdown_reasons;
374 last_reason = reason + nitems(xctrl_shutdown_reasons);
375 while (reason < last_reason) {
376 if (!strcmp(result, reason->name)) {
377 reason->handler();
378 break;
379 }
380 reason++;
381 }
382
383 free(result, M_XENSTORE);
384 }
385
386 /*------------------ Private Device Attachment Functions --------------------*/
387 /**
388 * \brief Identify instances of this device type in the system.
389 *
390 * \param driver The driver performing this identify action.
391 * \param parent The NewBus parent device for any devices this method adds.
392 */
393 static void
xctrl_identify(driver_t * driver __unused,device_t parent)394 xctrl_identify(driver_t *driver __unused, device_t parent)
395 {
396 /*
397 * A single device instance for our driver is always present
398 * in a system operating under Xen.
399 */
400 BUS_ADD_CHILD(parent, 0, driver->name, 0);
401 }
402
403 /**
404 * \brief Probe for the existence of the Xen Control device
405 *
406 * \param dev NewBus device_t for this Xen control instance.
407 *
408 * \return Always returns 0 indicating success.
409 */
410 static int
xctrl_probe(device_t dev)411 xctrl_probe(device_t dev)
412 {
413 device_set_desc(dev, "Xen Control Device");
414
415 return (BUS_PROBE_NOWILDCARD);
416 }
417
418 /**
419 * \brief Attach the Xen control device.
420 *
421 * \param dev NewBus device_t for this Xen control instance.
422 *
423 * \return On success, 0. Otherwise an errno value indicating the
424 * type of failure.
425 */
426 static int
xctrl_attach(device_t dev)427 xctrl_attach(device_t dev)
428 {
429 struct xctrl_softc *xctrl;
430
431 xctrl = device_get_softc(dev);
432
433 /* Activate watch */
434 xctrl->xctrl_watch.node = "control/shutdown";
435 xctrl->xctrl_watch.callback = xctrl_on_watch_event;
436 xctrl->xctrl_watch.callback_data = (uintptr_t)xctrl;
437 /*
438 * We don't care about the path updated, just about the value changes
439 * on that single node, hence there's no need to queue more that one
440 * event.
441 */
442 xctrl->xctrl_watch.max_pending = 1;
443 xs_register_watch(&xctrl->xctrl_watch);
444
445 if (xen_pv_domain())
446 EVENTHANDLER_REGISTER(shutdown_final, xen_pv_shutdown_final, NULL,
447 SHUTDOWN_PRI_LAST);
448
449 return (0);
450 }
451
452 /**
453 * \brief Detach the Xen control device.
454 *
455 * \param dev NewBus device_t for this Xen control device instance.
456 *
457 * \return On success, 0. Otherwise an errno value indicating the
458 * type of failure.
459 */
460 static int
xctrl_detach(device_t dev)461 xctrl_detach(device_t dev)
462 {
463 struct xctrl_softc *xctrl;
464
465 xctrl = device_get_softc(dev);
466
467 /* Release watch */
468 xs_unregister_watch(&xctrl->xctrl_watch);
469
470 return (0);
471 }
472
473 /*-------------------- Private Device Attachment Data -----------------------*/
474 static device_method_t xctrl_methods[] = {
475 /* Device interface */
476 DEVMETHOD(device_identify, xctrl_identify),
477 DEVMETHOD(device_probe, xctrl_probe),
478 DEVMETHOD(device_attach, xctrl_attach),
479 DEVMETHOD(device_detach, xctrl_detach),
480
481 DEVMETHOD_END
482 };
483
484 DEFINE_CLASS_0(xctrl, xctrl_driver, xctrl_methods, sizeof(struct xctrl_softc));
485 devclass_t xctrl_devclass;
486
487 DRIVER_MODULE(xctrl, xenstore, xctrl_driver, xctrl_devclass, NULL, NULL);
488