xref: /freebsd/sys/dev/xen/control/control.c (revision 4ea0b4ad1a4a2f3d2ffb0db8b7c24fe947f8480c)
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("$FreeBSD$");
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 #include <sys/timetc.h>
126 
127 #include <geom/geom.h>
128 
129 #include <machine/_inttypes.h>
130 #include <machine/intr_machdep.h>
131 
132 #include <x86/apicvar.h>
133 
134 #include <vm/vm.h>
135 #include <vm/vm_extern.h>
136 #include <vm/vm_kern.h>
137 
138 #include <xen/xen-os.h>
139 #include <xen/blkif.h>
140 #include <xen/evtchn.h>
141 #include <xen/gnttab.h>
142 #include <xen/xen_intr.h>
143 
144 #include <xen/hvm.h>
145 
146 #include <xen/interface/event_channel.h>
147 #include <xen/interface/grant_table.h>
148 
149 #include <xen/xenbus/xenbusvar.h>
150 
151 /*--------------------------- Forward Declarations --------------------------*/
152 /** Function signature for shutdown event handlers. */
153 typedef	void (xctrl_shutdown_handler_t)(void);
154 
155 static xctrl_shutdown_handler_t xctrl_poweroff;
156 static xctrl_shutdown_handler_t xctrl_reboot;
157 static xctrl_shutdown_handler_t xctrl_suspend;
158 static xctrl_shutdown_handler_t xctrl_crash;
159 
160 /*-------------------------- Private Data Structures -------------------------*/
161 /** Element type for lookup table of event name to handler. */
162 struct xctrl_shutdown_reason {
163 	const char		 *name;
164 	xctrl_shutdown_handler_t *handler;
165 };
166 
167 /** Lookup table for shutdown event name to handler. */
168 static const struct xctrl_shutdown_reason xctrl_shutdown_reasons[] = {
169 	{ "poweroff", xctrl_poweroff },
170 	{ "reboot",   xctrl_reboot   },
171 	{ "suspend",  xctrl_suspend  },
172 	{ "crash",    xctrl_crash    },
173 	{ "halt",     xctrl_poweroff },
174 };
175 
176 struct xctrl_softc {
177 	struct xs_watch    xctrl_watch;
178 };
179 
180 /*------------------------------ Event Handlers ------------------------------*/
181 static void
182 xctrl_poweroff()
183 {
184 	shutdown_nice(RB_POWEROFF|RB_HALT);
185 }
186 
187 static void
188 xctrl_reboot()
189 {
190 	shutdown_nice(0);
191 }
192 
193 static void
194 xctrl_suspend()
195 {
196 #ifdef SMP
197 	cpuset_t cpu_suspend_map;
198 #endif
199 	int suspend_cancelled;
200 
201 	EVENTHANDLER_INVOKE(power_suspend_early);
202 	stop_all_proc();
203 	EVENTHANDLER_INVOKE(power_suspend);
204 
205 	if (smp_started) {
206 		thread_lock(curthread);
207 		sched_bind(curthread, 0);
208 		thread_unlock(curthread);
209 	}
210 	KASSERT((PCPU_GET(cpuid) == 0), ("Not running on CPU#0"));
211 
212 	/*
213 	 * Clear our XenStore node so the toolstack knows we are
214 	 * responding to the suspend request.
215 	 */
216 	xs_write(XST_NIL, "control", "shutdown", "");
217 
218 	/*
219 	 * Be sure to hold Giant across DEVICE_SUSPEND/RESUME since non-MPSAFE
220 	 * drivers need this.
221 	 */
222 	mtx_lock(&Giant);
223 	if (DEVICE_SUSPEND(root_bus) != 0) {
224 		mtx_unlock(&Giant);
225 		printf("%s: device_suspend failed\n", __func__);
226 		return;
227 	}
228 
229 #ifdef SMP
230 	CPU_ZERO(&cpu_suspend_map);	/* silence gcc */
231 	if (smp_started) {
232 		/*
233 		 * Suspend other CPUs. This prevents IPIs while we
234 		 * are resuming, and will allow us to reset per-cpu
235 		 * vcpu_info on resume.
236 		 */
237 		cpu_suspend_map = all_cpus;
238 		CPU_CLR(PCPU_GET(cpuid), &cpu_suspend_map);
239 		if (!CPU_EMPTY(&cpu_suspend_map))
240 			suspend_cpus(cpu_suspend_map);
241 	}
242 #endif
243 
244 	/*
245 	 * Prevent any races with evtchn_interrupt() handler.
246 	 */
247 	disable_intr();
248 	intr_suspend();
249 	xen_hvm_suspend();
250 
251 	suspend_cancelled = HYPERVISOR_suspend(0);
252 
253 	xen_hvm_resume(suspend_cancelled != 0);
254 	intr_resume(suspend_cancelled != 0);
255 	enable_intr();
256 
257 	/*
258 	 * Reset grant table info.
259 	 */
260 	gnttab_resume(NULL);
261 
262 #ifdef SMP
263 	if (!CPU_EMPTY(&cpu_suspend_map)) {
264 		/*
265 		 * Now that event channels have been initialized,
266 		 * resume CPUs.
267 		 */
268 		resume_cpus(cpu_suspend_map);
269 		/* Send an IPI_BITMAP in case there are pending bitmap IPIs. */
270 		lapic_ipi_vectored(IPI_BITMAP_VECTOR, APIC_IPI_DEST_ALL);
271 	}
272 #endif
273 
274 	/*
275 	 * FreeBSD really needs to add DEVICE_SUSPEND_CANCEL or
276 	 * similar.
277 	 */
278 	DEVICE_RESUME(root_bus);
279 	mtx_unlock(&Giant);
280 
281 	/*
282 	 * Warm up timecounter again and reset system clock.
283 	 */
284 	timecounter->tc_get_timecount(timecounter);
285 	timecounter->tc_get_timecount(timecounter);
286 	inittodr(time_second);
287 
288 	if (smp_started) {
289 		thread_lock(curthread);
290 		sched_unbind(curthread);
291 		thread_unlock(curthread);
292 	}
293 
294 	resume_all_proc();
295 
296 	EVENTHANDLER_INVOKE(power_resume);
297 
298 	if (bootverbose)
299 		printf("System resumed after suspension\n");
300 
301 }
302 
303 static void
304 xctrl_crash()
305 {
306 	panic("Xen directed crash");
307 }
308 
309 static void
310 xen_pv_shutdown_final(void *arg, int howto)
311 {
312 	/*
313 	 * Inform the hypervisor that shutdown is complete.
314 	 * This is not necessary in HVM domains since Xen
315 	 * emulates ACPI in that mode and FreeBSD's ACPI
316 	 * support will request this transition.
317 	 */
318 	if (howto & (RB_HALT | RB_POWEROFF))
319 		HYPERVISOR_shutdown(SHUTDOWN_poweroff);
320 	else
321 		HYPERVISOR_shutdown(SHUTDOWN_reboot);
322 }
323 
324 /*------------------------------ Event Reception -----------------------------*/
325 static void
326 xctrl_on_watch_event(struct xs_watch *watch, const char **vec, unsigned int len)
327 {
328 	const struct xctrl_shutdown_reason *reason;
329 	const struct xctrl_shutdown_reason *last_reason;
330 	char *result;
331 	int   error;
332 	int   result_len;
333 
334 	error = xs_read(XST_NIL, "control", "shutdown",
335 			&result_len, (void **)&result);
336 	if (error != 0)
337 		return;
338 
339 	reason = xctrl_shutdown_reasons;
340 	last_reason = reason + nitems(xctrl_shutdown_reasons);
341 	while (reason < last_reason) {
342 
343 		if (!strcmp(result, reason->name)) {
344 			reason->handler();
345 			break;
346 		}
347 		reason++;
348 	}
349 
350 	free(result, M_XENSTORE);
351 }
352 
353 /*------------------ Private Device Attachment Functions  --------------------*/
354 /**
355  * \brief Identify instances of this device type in the system.
356  *
357  * \param driver  The driver performing this identify action.
358  * \param parent  The NewBus parent device for any devices this method adds.
359  */
360 static void
361 xctrl_identify(driver_t *driver __unused, device_t parent)
362 {
363 	/*
364 	 * A single device instance for our driver is always present
365 	 * in a system operating under Xen.
366 	 */
367 	BUS_ADD_CHILD(parent, 0, driver->name, 0);
368 }
369 
370 /**
371  * \brief Probe for the existence of the Xen Control device
372  *
373  * \param dev  NewBus device_t for this Xen control instance.
374  *
375  * \return  Always returns 0 indicating success.
376  */
377 static int
378 xctrl_probe(device_t dev)
379 {
380 	device_set_desc(dev, "Xen Control Device");
381 
382 	return (BUS_PROBE_NOWILDCARD);
383 }
384 
385 /**
386  * \brief Attach the Xen control device.
387  *
388  * \param dev  NewBus device_t for this Xen control instance.
389  *
390  * \return  On success, 0. Otherwise an errno value indicating the
391  *          type of failure.
392  */
393 static int
394 xctrl_attach(device_t dev)
395 {
396 	struct xctrl_softc *xctrl;
397 
398 	xctrl = device_get_softc(dev);
399 
400 	/* Activate watch */
401 	xctrl->xctrl_watch.node = "control/shutdown";
402 	xctrl->xctrl_watch.callback = xctrl_on_watch_event;
403 	xctrl->xctrl_watch.callback_data = (uintptr_t)xctrl;
404 	xs_register_watch(&xctrl->xctrl_watch);
405 
406 	if (xen_pv_domain())
407 		EVENTHANDLER_REGISTER(shutdown_final, xen_pv_shutdown_final, NULL,
408 		                      SHUTDOWN_PRI_LAST);
409 
410 	return (0);
411 }
412 
413 /**
414  * \brief Detach the Xen control device.
415  *
416  * \param dev  NewBus device_t for this Xen control device instance.
417  *
418  * \return  On success, 0. Otherwise an errno value indicating the
419  *          type of failure.
420  */
421 static int
422 xctrl_detach(device_t dev)
423 {
424 	struct xctrl_softc *xctrl;
425 
426 	xctrl = device_get_softc(dev);
427 
428 	/* Release watch */
429 	xs_unregister_watch(&xctrl->xctrl_watch);
430 
431 	return (0);
432 }
433 
434 /*-------------------- Private Device Attachment Data  -----------------------*/
435 static device_method_t xctrl_methods[] = {
436 	/* Device interface */
437 	DEVMETHOD(device_identify,	xctrl_identify),
438 	DEVMETHOD(device_probe,         xctrl_probe),
439 	DEVMETHOD(device_attach,        xctrl_attach),
440 	DEVMETHOD(device_detach,        xctrl_detach),
441 
442 	DEVMETHOD_END
443 };
444 
445 DEFINE_CLASS_0(xctrl, xctrl_driver, xctrl_methods, sizeof(struct xctrl_softc));
446 devclass_t xctrl_devclass;
447 
448 DRIVER_MODULE(xctrl, xenstore, xctrl_driver, xctrl_devclass, NULL, NULL);
449