control.c revision 315675
1/*-
2 * Copyright (c) 2010 Justin T. Gibbs, Spectra Logic Corporation
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions, and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    substantially similar to the "NO WARRANTY" disclaimer below
13 *    ("Disclaimer") and any redistribution must be conditioned upon
14 *    including a substantially similar Disclaimer requirement for further
15 *    binary redistribution.
16 *
17 * NO WARRANTY
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGES.
29 */
30
31/*-
32 * PV suspend/resume support:
33 *
34 * Copyright (c) 2004 Christian Limpach.
35 * Copyright (c) 2004-2006,2008 Kip Macy
36 * All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 *    notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 *    notice, this list of conditions and the following disclaimer in the
45 *    documentation and/or other materials provided with the distribution.
46 * 3. All advertising materials mentioning features or use of this software
47 *    must display the following acknowledgement:
48 *      This product includes software developed by Christian Limpach.
49 * 4. The name of the author may not be used to endorse or promote products
50 *    derived from this software without specific prior written permission.
51 *
52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
53 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
54 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
55 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
56 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
57 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
58 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
59 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
60 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
61 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
62 */
63
64/*-
65 * HVM suspend/resume support:
66 *
67 * Copyright (c) 2008 Citrix Systems, Inc.
68 * All rights reserved.
69 *
70 * Redistribution and use in source and binary forms, with or without
71 * modification, are permitted provided that the following conditions
72 * are met:
73 * 1. Redistributions of source code must retain the above copyright
74 *    notice, this list of conditions and the following disclaimer.
75 * 2. Redistributions in binary form must reproduce the above copyright
76 *    notice, this list of conditions and the following disclaimer in the
77 *    documentation and/or other materials provided with the distribution.
78 *
79 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
80 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
81 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
82 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
83 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
84 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
85 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
86 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
87 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
88 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
89 * SUCH DAMAGE.
90 */
91#include <sys/cdefs.h>
92__FBSDID("$FreeBSD: stable/10/sys/dev/xen/control/control.c 315675 2017-03-21 09:27:24Z royger $");
93
94/**
95 * \file control.c
96 *
97 * \brief Device driver to repond to control domain events that impact
98 *        this VM.
99 */
100
101#include <sys/param.h>
102#include <sys/systm.h>
103#include <sys/kernel.h>
104#include <sys/malloc.h>
105
106#include <sys/bio.h>
107#include <sys/bus.h>
108#include <sys/conf.h>
109#include <sys/disk.h>
110#include <sys/fcntl.h>
111#include <sys/filedesc.h>
112#include <sys/kdb.h>
113#include <sys/module.h>
114#include <sys/namei.h>
115#include <sys/proc.h>
116#include <sys/reboot.h>
117#include <sys/rman.h>
118#include <sys/sched.h>
119#include <sys/taskqueue.h>
120#include <sys/types.h>
121#include <sys/vnode.h>
122#include <sys/sched.h>
123#include <sys/smp.h>
124#include <sys/eventhandler.h>
125
126#include <geom/geom.h>
127
128#include <machine/_inttypes.h>
129#include <machine/intr_machdep.h>
130#include <machine/apicvar.h>
131
132#include <vm/vm.h>
133#include <vm/vm_extern.h>
134#include <vm/vm_kern.h>
135
136#include <xen/xen-os.h>
137#include <xen/blkif.h>
138#include <xen/evtchn.h>
139#include <xen/gnttab.h>
140#include <xen/xen_intr.h>
141
142#ifdef XENHVM
143#include <xen/hvm.h>
144#endif
145
146#include <xen/interface/event_channel.h>
147#include <xen/interface/grant_table.h>
148
149#include <xen/xenbus/xenbusvar.h>
150
151#include <machine/xen/xenvar.h>
152#include <machine/xen/xenfunc.h>
153
154/*--------------------------- Forward Declarations --------------------------*/
155/** Function signature for shutdown event handlers. */
156typedef	void (xctrl_shutdown_handler_t)(void);
157
158static xctrl_shutdown_handler_t xctrl_poweroff;
159static xctrl_shutdown_handler_t xctrl_reboot;
160static xctrl_shutdown_handler_t xctrl_suspend;
161static xctrl_shutdown_handler_t xctrl_crash;
162
163/*-------------------------- Private Data Structures -------------------------*/
164/** Element type for lookup table of event name to handler. */
165struct xctrl_shutdown_reason {
166	const char		 *name;
167	xctrl_shutdown_handler_t *handler;
168};
169
170/** Lookup table for shutdown event name to handler. */
171static const struct xctrl_shutdown_reason xctrl_shutdown_reasons[] = {
172	{ "poweroff", xctrl_poweroff },
173	{ "reboot",   xctrl_reboot   },
174	{ "suspend",  xctrl_suspend  },
175	{ "crash",    xctrl_crash    },
176	{ "halt",     xctrl_poweroff },
177};
178
179struct xctrl_softc {
180	struct xs_watch    xctrl_watch;
181};
182
183/*------------------------------ Event Handlers ------------------------------*/
184static void
185xctrl_poweroff()
186{
187	shutdown_nice(RB_POWEROFF|RB_HALT);
188}
189
190static void
191xctrl_reboot()
192{
193	shutdown_nice(0);
194}
195
196#ifndef XENHVM
197extern void xencons_suspend(void);
198extern void xencons_resume(void);
199
200/* Full PV mode suspension. */
201static void
202xctrl_suspend()
203{
204	int i, j, k, fpp, suspend_cancelled;
205	unsigned long max_pfn, start_info_mfn;
206
207	EVENTHANDLER_INVOKE(power_suspend);
208
209#ifdef SMP
210	struct thread *td;
211	cpuset_t map;
212	u_int cpuid;
213
214	/*
215	 * Bind us to CPU 0 and stop any other VCPUs.
216	 */
217	td = curthread;
218	thread_lock(td);
219	sched_bind(td, 0);
220	thread_unlock(td);
221	cpuid = PCPU_GET(cpuid);
222	KASSERT(cpuid == 0, ("xen_suspend: not running on cpu 0"));
223
224	map = all_cpus;
225	CPU_CLR(cpuid, &map);
226	CPU_NAND(&map, &stopped_cpus);
227	if (!CPU_EMPTY(&map))
228		stop_cpus(map);
229#endif
230
231	/*
232	 * Be sure to hold Giant across DEVICE_SUSPEND/RESUME since non-MPSAFE
233	 * drivers need this.
234	 */
235	mtx_lock(&Giant);
236	if (DEVICE_SUSPEND(root_bus) != 0) {
237		mtx_unlock(&Giant);
238		printf("%s: device_suspend failed\n", __func__);
239#ifdef SMP
240		if (!CPU_EMPTY(&map))
241			restart_cpus(map);
242#endif
243		return;
244	}
245	mtx_unlock(&Giant);
246
247	local_irq_disable();
248
249	xencons_suspend();
250	gnttab_suspend();
251	intr_suspend();
252
253	max_pfn = HYPERVISOR_shared_info->arch.max_pfn;
254
255	void *shared_info = HYPERVISOR_shared_info;
256	HYPERVISOR_shared_info = NULL;
257	pmap_kremove((vm_offset_t) shared_info);
258	PT_UPDATES_FLUSH();
259
260	xen_start_info->store_mfn = MFNTOPFN(xen_start_info->store_mfn);
261	xen_start_info->console.domU.mfn = MFNTOPFN(xen_start_info->console.domU.mfn);
262
263	/*
264	 * We'll stop somewhere inside this hypercall. When it returns,
265	 * we'll start resuming after the restore.
266	 */
267	start_info_mfn = VTOMFN(xen_start_info);
268	pmap_suspend();
269	suspend_cancelled = HYPERVISOR_suspend(start_info_mfn);
270	pmap_resume();
271
272	pmap_kenter_ma((vm_offset_t) shared_info, xen_start_info->shared_info);
273	HYPERVISOR_shared_info = shared_info;
274
275	HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list =
276		VTOMFN(xen_pfn_to_mfn_frame_list_list);
277
278	fpp = PAGE_SIZE/sizeof(unsigned long);
279	for (i = 0, j = 0, k = -1; i < max_pfn; i += fpp, j++) {
280		if ((j % fpp) == 0) {
281			k++;
282			xen_pfn_to_mfn_frame_list_list[k] =
283				VTOMFN(xen_pfn_to_mfn_frame_list[k]);
284			j = 0;
285		}
286		xen_pfn_to_mfn_frame_list[k][j] =
287			VTOMFN(&xen_phys_machine[i]);
288	}
289	HYPERVISOR_shared_info->arch.max_pfn = max_pfn;
290
291	gnttab_resume();
292	intr_resume(suspend_cancelled != 0);
293	local_irq_enable();
294	xencons_resume();
295
296#ifdef CONFIG_SMP
297	for_each_cpu(i)
298		vcpu_prepare(i);
299
300#endif
301
302	/*
303	 * Only resume xenbus /after/ we've prepared our VCPUs; otherwise
304	 * the VCPU hotplug callback can race with our vcpu_prepare
305	 */
306	mtx_lock(&Giant);
307	DEVICE_RESUME(root_bus);
308	mtx_unlock(&Giant);
309
310#ifdef SMP
311	thread_lock(curthread);
312	sched_unbind(curthread);
313	thread_unlock(curthread);
314	if (!CPU_EMPTY(&map))
315		restart_cpus(map);
316#endif
317	EVENTHANDLER_INVOKE(power_resume);
318}
319
320static void
321xen_pv_shutdown_final(void *arg, int howto)
322{
323	/*
324	 * Inform the hypervisor that shutdown is complete.
325	 * This is not necessary in HVM domains since Xen
326	 * emulates ACPI in that mode and FreeBSD's ACPI
327	 * support will request this transition.
328	 */
329	if (howto & (RB_HALT | RB_POWEROFF))
330		HYPERVISOR_shutdown(SHUTDOWN_poweroff);
331	else
332		HYPERVISOR_shutdown(SHUTDOWN_reboot);
333}
334
335#else
336
337/* HVM mode suspension. */
338static void
339xctrl_suspend()
340{
341#ifdef SMP
342	cpuset_t cpu_suspend_map;
343#endif
344	int suspend_cancelled;
345
346	EVENTHANDLER_INVOKE(power_suspend_early);
347	xs_lock();
348	stop_all_proc();
349	xs_unlock();
350	EVENTHANDLER_INVOKE(power_suspend);
351
352	if (smp_started) {
353		thread_lock(curthread);
354		sched_bind(curthread, 0);
355		thread_unlock(curthread);
356	}
357	KASSERT((PCPU_GET(cpuid) == 0), ("Not running on CPU#0"));
358
359	/*
360	 * Clear our XenStore node so the toolstack knows we are
361	 * responding to the suspend request.
362	 */
363	xs_write(XST_NIL, "control", "shutdown", "");
364
365	/*
366	 * Be sure to hold Giant across DEVICE_SUSPEND/RESUME since non-MPSAFE
367	 * drivers need this.
368	 */
369	mtx_lock(&Giant);
370	if (DEVICE_SUSPEND(root_bus) != 0) {
371		mtx_unlock(&Giant);
372		printf("%s: device_suspend failed\n", __func__);
373		return;
374	}
375	mtx_unlock(&Giant);
376
377#ifdef SMP
378	CPU_ZERO(&cpu_suspend_map);	/* silence gcc */
379	if (smp_started) {
380		/*
381		 * Suspend other CPUs. This prevents IPIs while we
382		 * are resuming, and will allow us to reset per-cpu
383		 * vcpu_info on resume.
384		 */
385		cpu_suspend_map = all_cpus;
386		CPU_CLR(PCPU_GET(cpuid), &cpu_suspend_map);
387		if (!CPU_EMPTY(&cpu_suspend_map))
388			suspend_cpus(cpu_suspend_map);
389	}
390#endif
391
392	/*
393	 * Prevent any races with evtchn_interrupt() handler.
394	 */
395	disable_intr();
396	intr_suspend();
397	xen_hvm_suspend();
398
399	suspend_cancelled = HYPERVISOR_suspend(0);
400
401	xen_hvm_resume(suspend_cancelled != 0);
402	intr_resume(suspend_cancelled != 0);
403	enable_intr();
404
405	/*
406	 * Reset grant table info.
407	 */
408	gnttab_resume();
409
410#ifdef SMP
411	/* Send an IPI_BITMAP in case there are pending bitmap IPIs. */
412	lapic_ipi_vectored(IPI_BITMAP_VECTOR, APIC_IPI_DEST_ALL);
413	if (smp_started && !CPU_EMPTY(&cpu_suspend_map)) {
414		/*
415		 * Now that event channels have been initialized,
416		 * resume CPUs.
417		 */
418		resume_cpus(cpu_suspend_map);
419	}
420#endif
421
422	/*
423	 * FreeBSD really needs to add DEVICE_SUSPEND_CANCEL or
424	 * similar.
425	 */
426	mtx_lock(&Giant);
427	DEVICE_RESUME(root_bus);
428	mtx_unlock(&Giant);
429
430	if (smp_started) {
431		thread_lock(curthread);
432		sched_unbind(curthread);
433		thread_unlock(curthread);
434	}
435
436	resume_all_proc();
437
438	EVENTHANDLER_INVOKE(power_resume);
439
440	if (bootverbose)
441		printf("System resumed after suspension\n");
442
443}
444#endif
445
446static void
447xctrl_crash()
448{
449	panic("Xen directed crash");
450}
451
452/*------------------------------ Event Reception -----------------------------*/
453static void
454xctrl_on_watch_event(struct xs_watch *watch, const char **vec, unsigned int len)
455{
456	const struct xctrl_shutdown_reason *reason;
457	const struct xctrl_shutdown_reason *last_reason;
458	char *result;
459	int   error;
460	int   result_len;
461
462	error = xs_read(XST_NIL, "control", "shutdown",
463			&result_len, (void **)&result);
464	if (error != 0)
465		return;
466
467	reason = xctrl_shutdown_reasons;
468	last_reason = reason + nitems(xctrl_shutdown_reasons);
469	while (reason < last_reason) {
470
471		if (!strcmp(result, reason->name)) {
472			reason->handler();
473			break;
474		}
475		reason++;
476	}
477
478	free(result, M_XENSTORE);
479}
480
481/*------------------ Private Device Attachment Functions  --------------------*/
482/**
483 * \brief Identify instances of this device type in the system.
484 *
485 * \param driver  The driver performing this identify action.
486 * \param parent  The NewBus parent device for any devices this method adds.
487 */
488static void
489xctrl_identify(driver_t *driver __unused, device_t parent)
490{
491	/*
492	 * A single device instance for our driver is always present
493	 * in a system operating under Xen.
494	 */
495	BUS_ADD_CHILD(parent, 0, driver->name, 0);
496}
497
498/**
499 * \brief Probe for the existance of the Xen Control device
500 *
501 * \param dev  NewBus device_t for this Xen control instance.
502 *
503 * \return  Always returns 0 indicating success.
504 */
505static int
506xctrl_probe(device_t dev)
507{
508	device_set_desc(dev, "Xen Control Device");
509
510	return (0);
511}
512
513/**
514 * \brief Attach the Xen control device.
515 *
516 * \param dev  NewBus device_t for this Xen control instance.
517 *
518 * \return  On success, 0. Otherwise an errno value indicating the
519 *          type of failure.
520 */
521static int
522xctrl_attach(device_t dev)
523{
524	struct xctrl_softc *xctrl;
525
526	xctrl = device_get_softc(dev);
527
528	/* Activate watch */
529	xctrl->xctrl_watch.node = "control/shutdown";
530	xctrl->xctrl_watch.callback = xctrl_on_watch_event;
531	xctrl->xctrl_watch.callback_data = (uintptr_t)xctrl;
532	xs_register_watch(&xctrl->xctrl_watch);
533
534#ifndef XENHVM
535	EVENTHANDLER_REGISTER(shutdown_final, xen_pv_shutdown_final, NULL,
536			      SHUTDOWN_PRI_LAST);
537#endif
538
539	return (0);
540}
541
542/**
543 * \brief Detach the Xen control device.
544 *
545 * \param dev  NewBus device_t for this Xen control device instance.
546 *
547 * \return  On success, 0. Otherwise an errno value indicating the
548 *          type of failure.
549 */
550static int
551xctrl_detach(device_t dev)
552{
553	struct xctrl_softc *xctrl;
554
555	xctrl = device_get_softc(dev);
556
557	/* Release watch */
558	xs_unregister_watch(&xctrl->xctrl_watch);
559
560	return (0);
561}
562
563/*-------------------- Private Device Attachment Data  -----------------------*/
564static device_method_t xctrl_methods[] = {
565	/* Device interface */
566	DEVMETHOD(device_identify,	xctrl_identify),
567	DEVMETHOD(device_probe,         xctrl_probe),
568	DEVMETHOD(device_attach,        xctrl_attach),
569	DEVMETHOD(device_detach,        xctrl_detach),
570
571	DEVMETHOD_END
572};
573
574DEFINE_CLASS_0(xctrl, xctrl_driver, xctrl_methods, sizeof(struct xctrl_softc));
575devclass_t xctrl_devclass;
576
577DRIVER_MODULE(xctrl, xenstore, xctrl_driver, xctrl_devclass, NULL, NULL);
578