1/*
2 * Xen SMP support
3 *
4 * This file implements the Xen versions of smp_ops.  SMP under Xen is
5 * very straightforward.  Bringing a CPU up is simply a matter of
6 * loading its initial context and setting it running.
7 *
8 * IPIs are handled through the Xen event mechanism.
9 *
10 * Because virtual CPUs can be scheduled onto any real CPU, there's no
11 * useful topology information for the kernel to make use of.  As a
12 * result, all CPUs are treated as if they're single-core and
13 * single-threaded.
14 */
15#include <linux/sched.h>
16#include <linux/err.h>
17#include <linux/slab.h>
18#include <linux/smp.h>
19#include <linux/irq_work.h>
20#include <linux/tick.h>
21
22#include <asm/paravirt.h>
23#include <asm/desc.h>
24#include <asm/pgtable.h>
25#include <asm/cpu.h>
26
27#include <xen/interface/xen.h>
28#include <xen/interface/vcpu.h>
29#include <xen/interface/xenpmu.h>
30
31#include <asm/xen/interface.h>
32#include <asm/xen/hypercall.h>
33
34#include <xen/xen.h>
35#include <xen/page.h>
36#include <xen/events.h>
37
38#include <xen/hvc-console.h>
39#include "xen-ops.h"
40#include "mmu.h"
41#include "smp.h"
42#include "pmu.h"
43
44cpumask_var_t xen_cpu_initialized_map;
45
46struct xen_common_irq {
47	int irq;
48	char *name;
49};
50static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
51static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
52static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
53static DEFINE_PER_CPU(struct xen_common_irq, xen_irq_work) = { .irq = -1 };
54static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
55static DEFINE_PER_CPU(struct xen_common_irq, xen_pmu_irq) = { .irq = -1 };
56
57static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
58static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
59static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id);
60
61/*
62 * Reschedule call back.
63 */
64static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
65{
66	inc_irq_stat(irq_resched_count);
67	scheduler_ipi();
68
69	return IRQ_HANDLED;
70}
71
72static void cpu_bringup(void)
73{
74	int cpu;
75
76	cpu_init();
77	touch_softlockup_watchdog();
78	preempt_disable();
79
80	/* PVH runs in ring 0 and allows us to do native syscalls. Yay! */
81	if (!xen_feature(XENFEAT_supervisor_mode_kernel)) {
82		xen_enable_sysenter();
83		xen_enable_syscall();
84	}
85	cpu = smp_processor_id();
86	smp_store_cpu_info(cpu);
87	cpu_data(cpu).x86_max_cores = 1;
88	set_cpu_sibling_map(cpu);
89
90	xen_setup_cpu_clockevents();
91
92	notify_cpu_starting(cpu);
93
94	set_cpu_online(cpu, true);
95
96	cpu_set_state_online(cpu);  /* Implies full memory barrier. */
97
98	/* We can take interrupts now: we're officially "up". */
99	local_irq_enable();
100}
101
102/*
103 * Note: cpu parameter is only relevant for PVH. The reason for passing it
104 * is we can't do smp_processor_id until the percpu segments are loaded, for
105 * which we need the cpu number! So we pass it in rdi as first parameter.
106 */
107asmlinkage __visible void cpu_bringup_and_idle(int cpu)
108{
109#ifdef CONFIG_XEN_PVH
110	if (xen_feature(XENFEAT_auto_translated_physmap) &&
111	    xen_feature(XENFEAT_supervisor_mode_kernel))
112		xen_pvh_secondary_vcpu_init(cpu);
113#endif
114	cpu_bringup();
115	cpu_startup_entry(CPUHP_ONLINE);
116}
117
118static void xen_smp_intr_free(unsigned int cpu)
119{
120	if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
121		unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
122		per_cpu(xen_resched_irq, cpu).irq = -1;
123		kfree(per_cpu(xen_resched_irq, cpu).name);
124		per_cpu(xen_resched_irq, cpu).name = NULL;
125	}
126	if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
127		unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
128		per_cpu(xen_callfunc_irq, cpu).irq = -1;
129		kfree(per_cpu(xen_callfunc_irq, cpu).name);
130		per_cpu(xen_callfunc_irq, cpu).name = NULL;
131	}
132	if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
133		unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
134		per_cpu(xen_debug_irq, cpu).irq = -1;
135		kfree(per_cpu(xen_debug_irq, cpu).name);
136		per_cpu(xen_debug_irq, cpu).name = NULL;
137	}
138	if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
139		unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
140				       NULL);
141		per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
142		kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
143		per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
144	}
145	if (xen_hvm_domain())
146		return;
147
148	if (per_cpu(xen_irq_work, cpu).irq >= 0) {
149		unbind_from_irqhandler(per_cpu(xen_irq_work, cpu).irq, NULL);
150		per_cpu(xen_irq_work, cpu).irq = -1;
151		kfree(per_cpu(xen_irq_work, cpu).name);
152		per_cpu(xen_irq_work, cpu).name = NULL;
153	}
154
155	if (per_cpu(xen_pmu_irq, cpu).irq >= 0) {
156		unbind_from_irqhandler(per_cpu(xen_pmu_irq, cpu).irq, NULL);
157		per_cpu(xen_pmu_irq, cpu).irq = -1;
158		kfree(per_cpu(xen_pmu_irq, cpu).name);
159		per_cpu(xen_pmu_irq, cpu).name = NULL;
160	}
161};
162static int xen_smp_intr_init(unsigned int cpu)
163{
164	int rc;
165	char *resched_name, *callfunc_name, *debug_name, *pmu_name;
166
167	resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
168	rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
169				    cpu,
170				    xen_reschedule_interrupt,
171				    IRQF_PERCPU|IRQF_NOBALANCING,
172				    resched_name,
173				    NULL);
174	if (rc < 0)
175		goto fail;
176	per_cpu(xen_resched_irq, cpu).irq = rc;
177	per_cpu(xen_resched_irq, cpu).name = resched_name;
178
179	callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
180	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
181				    cpu,
182				    xen_call_function_interrupt,
183				    IRQF_PERCPU|IRQF_NOBALANCING,
184				    callfunc_name,
185				    NULL);
186	if (rc < 0)
187		goto fail;
188	per_cpu(xen_callfunc_irq, cpu).irq = rc;
189	per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
190
191	debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
192	rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
193				     IRQF_PERCPU | IRQF_NOBALANCING,
194				     debug_name, NULL);
195	if (rc < 0)
196		goto fail;
197	per_cpu(xen_debug_irq, cpu).irq = rc;
198	per_cpu(xen_debug_irq, cpu).name = debug_name;
199
200	callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
201	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
202				    cpu,
203				    xen_call_function_single_interrupt,
204				    IRQF_PERCPU|IRQF_NOBALANCING,
205				    callfunc_name,
206				    NULL);
207	if (rc < 0)
208		goto fail;
209	per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
210	per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
211
212	/*
213	 * The IRQ worker on PVHVM goes through the native path and uses the
214	 * IPI mechanism.
215	 */
216	if (xen_hvm_domain())
217		return 0;
218
219	callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu);
220	rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR,
221				    cpu,
222				    xen_irq_work_interrupt,
223				    IRQF_PERCPU|IRQF_NOBALANCING,
224				    callfunc_name,
225				    NULL);
226	if (rc < 0)
227		goto fail;
228	per_cpu(xen_irq_work, cpu).irq = rc;
229	per_cpu(xen_irq_work, cpu).name = callfunc_name;
230
231	if (is_xen_pmu(cpu)) {
232		pmu_name = kasprintf(GFP_KERNEL, "pmu%d", cpu);
233		rc = bind_virq_to_irqhandler(VIRQ_XENPMU, cpu,
234					     xen_pmu_irq_handler,
235					     IRQF_PERCPU|IRQF_NOBALANCING,
236					     pmu_name, NULL);
237		if (rc < 0)
238			goto fail;
239		per_cpu(xen_pmu_irq, cpu).irq = rc;
240		per_cpu(xen_pmu_irq, cpu).name = pmu_name;
241	}
242
243	return 0;
244
245 fail:
246	xen_smp_intr_free(cpu);
247	return rc;
248}
249
250static void __init xen_fill_possible_map(void)
251{
252	int i, rc;
253
254	if (xen_initial_domain())
255		return;
256
257	for (i = 0; i < nr_cpu_ids; i++) {
258		rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
259		if (rc >= 0) {
260			num_processors++;
261			set_cpu_possible(i, true);
262		}
263	}
264}
265
266static void __init xen_filter_cpu_maps(void)
267{
268	int i, rc;
269	unsigned int subtract = 0;
270
271	if (!xen_initial_domain())
272		return;
273
274	num_processors = 0;
275	disabled_cpus = 0;
276	for (i = 0; i < nr_cpu_ids; i++) {
277		rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
278		if (rc >= 0) {
279			num_processors++;
280			set_cpu_possible(i, true);
281		} else {
282			set_cpu_possible(i, false);
283			set_cpu_present(i, false);
284			subtract++;
285		}
286	}
287#ifdef CONFIG_HOTPLUG_CPU
288	/* This is akin to using 'nr_cpus' on the Linux command line.
289	 * Which is OK as when we use 'dom0_max_vcpus=X' we can only
290	 * have up to X, while nr_cpu_ids is greater than X. This
291	 * normally is not a problem, except when CPU hotplugging
292	 * is involved and then there might be more than X CPUs
293	 * in the guest - which will not work as there is no
294	 * hypercall to expand the max number of VCPUs an already
295	 * running guest has. So cap it up to X. */
296	if (subtract)
297		nr_cpu_ids = nr_cpu_ids - subtract;
298#endif
299
300}
301
302static void __init xen_smp_prepare_boot_cpu(void)
303{
304	BUG_ON(smp_processor_id() != 0);
305	native_smp_prepare_boot_cpu();
306
307	if (xen_pv_domain()) {
308		if (!xen_feature(XENFEAT_writable_page_tables))
309			/* We've switched to the "real" per-cpu gdt, so make
310			 * sure the old memory can be recycled. */
311			make_lowmem_page_readwrite(xen_initial_gdt);
312
313#ifdef CONFIG_X86_32
314		/*
315		 * Xen starts us with XEN_FLAT_RING1_DS, but linux code
316		 * expects __USER_DS
317		 */
318		loadsegment(ds, __USER_DS);
319		loadsegment(es, __USER_DS);
320#endif
321
322		xen_filter_cpu_maps();
323		xen_setup_vcpu_info_placement();
324	}
325	/*
326	 * The alternative logic (which patches the unlock/lock) runs before
327	 * the smp bootup up code is activated. Hence we need to set this up
328	 * the core kernel is being patched. Otherwise we will have only
329	 * modules patched but not core code.
330	 */
331	xen_init_spinlocks();
332}
333
334static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
335{
336	unsigned cpu;
337	unsigned int i;
338
339	if (skip_ioapic_setup) {
340		char *m = (max_cpus == 0) ?
341			"The nosmp parameter is incompatible with Xen; " \
342			"use Xen dom0_max_vcpus=1 parameter" :
343			"The noapic parameter is incompatible with Xen";
344
345		xen_raw_printk(m);
346		panic(m);
347	}
348	xen_init_lock_cpu(0);
349
350	smp_store_boot_cpu_info();
351	cpu_data(0).x86_max_cores = 1;
352
353	for_each_possible_cpu(i) {
354		zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
355		zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
356		zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
357	}
358	set_cpu_sibling_map(0);
359
360	xen_pmu_init(0);
361
362	if (xen_smp_intr_init(0))
363		BUG();
364
365	if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
366		panic("could not allocate xen_cpu_initialized_map\n");
367
368	cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
369
370	/* Restrict the possible_map according to max_cpus. */
371	while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
372		for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
373			continue;
374		set_cpu_possible(cpu, false);
375	}
376
377	for_each_possible_cpu(cpu)
378		set_cpu_present(cpu, true);
379}
380
381static int
382cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
383{
384	struct vcpu_guest_context *ctxt;
385	struct desc_struct *gdt;
386	unsigned long gdt_mfn;
387
388	/* used to tell cpu_init() that it can proceed with initialization */
389	cpumask_set_cpu(cpu, cpu_callout_mask);
390	if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
391		return 0;
392
393	ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
394	if (ctxt == NULL)
395		return -ENOMEM;
396
397	gdt = get_cpu_gdt_table(cpu);
398
399#ifdef CONFIG_X86_32
400	/* Note: PVH is not yet supported on x86_32. */
401	ctxt->user_regs.fs = __KERNEL_PERCPU;
402	ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
403#endif
404	memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
405
406	if (!xen_feature(XENFEAT_auto_translated_physmap)) {
407		ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
408		ctxt->flags = VGCF_IN_KERNEL;
409		ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
410		ctxt->user_regs.ds = __USER_DS;
411		ctxt->user_regs.es = __USER_DS;
412		ctxt->user_regs.ss = __KERNEL_DS;
413
414		xen_copy_trap_info(ctxt->trap_ctxt);
415
416		ctxt->ldt_ents = 0;
417
418		BUG_ON((unsigned long)gdt & ~PAGE_MASK);
419
420		gdt_mfn = arbitrary_virt_to_mfn(gdt);
421		make_lowmem_page_readonly(gdt);
422		make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
423
424		ctxt->gdt_frames[0] = gdt_mfn;
425		ctxt->gdt_ents      = GDT_ENTRIES;
426
427		ctxt->kernel_ss = __KERNEL_DS;
428		ctxt->kernel_sp = idle->thread.sp0;
429
430#ifdef CONFIG_X86_32
431		ctxt->event_callback_cs     = __KERNEL_CS;
432		ctxt->failsafe_callback_cs  = __KERNEL_CS;
433#else
434		ctxt->gs_base_kernel = per_cpu_offset(cpu);
435#endif
436		ctxt->event_callback_eip    =
437					(unsigned long)xen_hypervisor_callback;
438		ctxt->failsafe_callback_eip =
439					(unsigned long)xen_failsafe_callback;
440		ctxt->user_regs.cs = __KERNEL_CS;
441		per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
442	}
443#ifdef CONFIG_XEN_PVH
444	else {
445		/*
446		 * The vcpu comes on kernel page tables which have the NX pte
447		 * bit set. This means before DS/SS is touched, NX in
448		 * EFER must be set. Hence the following assembly glue code.
449		 */
450		ctxt->user_regs.eip = (unsigned long)xen_pvh_early_cpu_init;
451		ctxt->user_regs.rdi = cpu;
452		ctxt->user_regs.rsi = true;  /* entry == true */
453	}
454#endif
455	ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
456	ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_gfn(swapper_pg_dir));
457	if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
458		BUG();
459
460	kfree(ctxt);
461	return 0;
462}
463
464static int xen_cpu_up(unsigned int cpu, struct task_struct *idle)
465{
466	int rc;
467
468	common_cpu_up(cpu, idle);
469
470	xen_setup_runstate_info(cpu);
471	xen_setup_timer(cpu);
472	xen_init_lock_cpu(cpu);
473
474	/*
475	 * PV VCPUs are always successfully taken down (see 'while' loop
476	 * in xen_cpu_die()), so -EBUSY is an error.
477	 */
478	rc = cpu_check_up_prepare(cpu);
479	if (rc)
480		return rc;
481
482	/* make sure interrupts start blocked */
483	per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
484
485	rc = cpu_initialize_context(cpu, idle);
486	if (rc)
487		return rc;
488
489	xen_pmu_init(cpu);
490
491	rc = xen_smp_intr_init(cpu);
492	if (rc)
493		return rc;
494
495	rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
496	BUG_ON(rc);
497
498	while (cpu_report_state(cpu) != CPU_ONLINE)
499		HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
500
501	return 0;
502}
503
504static void xen_smp_cpus_done(unsigned int max_cpus)
505{
506}
507
508#ifdef CONFIG_HOTPLUG_CPU
509static int xen_cpu_disable(void)
510{
511	unsigned int cpu = smp_processor_id();
512	if (cpu == 0)
513		return -EBUSY;
514
515	cpu_disable_common();
516
517	load_cr3(swapper_pg_dir);
518	return 0;
519}
520
521static void xen_cpu_die(unsigned int cpu)
522{
523	while (xen_pv_domain() && HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
524		__set_current_state(TASK_UNINTERRUPTIBLE);
525		schedule_timeout(HZ/10);
526	}
527
528	if (common_cpu_die(cpu) == 0) {
529		xen_smp_intr_free(cpu);
530		xen_uninit_lock_cpu(cpu);
531		xen_teardown_timer(cpu);
532		xen_pmu_finish(cpu);
533	}
534}
535
536static void xen_play_dead(void) /* used only with HOTPLUG_CPU */
537{
538	play_dead_common();
539	HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
540	cpu_bringup();
541	/*
542	 * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down)
543	 * clears certain data that the cpu_idle loop (which called us
544	 * and that we return from) expects. The only way to get that
545	 * data back is to call:
546	 */
547	tick_nohz_idle_enter();
548}
549
550#else /* !CONFIG_HOTPLUG_CPU */
551static int xen_cpu_disable(void)
552{
553	return -ENOSYS;
554}
555
556static void xen_cpu_die(unsigned int cpu)
557{
558	BUG();
559}
560
561static void xen_play_dead(void)
562{
563	BUG();
564}
565
566#endif
567static void stop_self(void *v)
568{
569	int cpu = smp_processor_id();
570
571	/* make sure we're not pinning something down */
572	load_cr3(swapper_pg_dir);
573	/* should set up a minimal gdt */
574
575	set_cpu_online(cpu, false);
576
577	HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
578	BUG();
579}
580
581static void xen_stop_other_cpus(int wait)
582{
583	smp_call_function(stop_self, NULL, wait);
584}
585
586static void xen_smp_send_reschedule(int cpu)
587{
588	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
589}
590
591static void __xen_send_IPI_mask(const struct cpumask *mask,
592			      int vector)
593{
594	unsigned cpu;
595
596	for_each_cpu_and(cpu, mask, cpu_online_mask)
597		xen_send_IPI_one(cpu, vector);
598}
599
600static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
601{
602	int cpu;
603
604	__xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
605
606	/* Make sure other vcpus get a chance to run if they need to. */
607	for_each_cpu(cpu, mask) {
608		if (xen_vcpu_stolen(cpu)) {
609			HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
610			break;
611		}
612	}
613}
614
615static void xen_smp_send_call_function_single_ipi(int cpu)
616{
617	__xen_send_IPI_mask(cpumask_of(cpu),
618			  XEN_CALL_FUNCTION_SINGLE_VECTOR);
619}
620
621static inline int xen_map_vector(int vector)
622{
623	int xen_vector;
624
625	switch (vector) {
626	case RESCHEDULE_VECTOR:
627		xen_vector = XEN_RESCHEDULE_VECTOR;
628		break;
629	case CALL_FUNCTION_VECTOR:
630		xen_vector = XEN_CALL_FUNCTION_VECTOR;
631		break;
632	case CALL_FUNCTION_SINGLE_VECTOR:
633		xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
634		break;
635	case IRQ_WORK_VECTOR:
636		xen_vector = XEN_IRQ_WORK_VECTOR;
637		break;
638#ifdef CONFIG_X86_64
639	case NMI_VECTOR:
640	case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
641		xen_vector = XEN_NMI_VECTOR;
642		break;
643#endif
644	default:
645		xen_vector = -1;
646		printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
647			vector);
648	}
649
650	return xen_vector;
651}
652
653void xen_send_IPI_mask(const struct cpumask *mask,
654			      int vector)
655{
656	int xen_vector = xen_map_vector(vector);
657
658	if (xen_vector >= 0)
659		__xen_send_IPI_mask(mask, xen_vector);
660}
661
662void xen_send_IPI_all(int vector)
663{
664	int xen_vector = xen_map_vector(vector);
665
666	if (xen_vector >= 0)
667		__xen_send_IPI_mask(cpu_online_mask, xen_vector);
668}
669
670void xen_send_IPI_self(int vector)
671{
672	int xen_vector = xen_map_vector(vector);
673
674	if (xen_vector >= 0)
675		xen_send_IPI_one(smp_processor_id(), xen_vector);
676}
677
678void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
679				int vector)
680{
681	unsigned cpu;
682	unsigned int this_cpu = smp_processor_id();
683	int xen_vector = xen_map_vector(vector);
684
685	if (!(num_online_cpus() > 1) || (xen_vector < 0))
686		return;
687
688	for_each_cpu_and(cpu, mask, cpu_online_mask) {
689		if (this_cpu == cpu)
690			continue;
691
692		xen_send_IPI_one(cpu, xen_vector);
693	}
694}
695
696void xen_send_IPI_allbutself(int vector)
697{
698	xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
699}
700
701static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
702{
703	irq_enter();
704	generic_smp_call_function_interrupt();
705	inc_irq_stat(irq_call_count);
706	irq_exit();
707
708	return IRQ_HANDLED;
709}
710
711static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
712{
713	irq_enter();
714	generic_smp_call_function_single_interrupt();
715	inc_irq_stat(irq_call_count);
716	irq_exit();
717
718	return IRQ_HANDLED;
719}
720
721static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
722{
723	irq_enter();
724	irq_work_run();
725	inc_irq_stat(apic_irq_work_irqs);
726	irq_exit();
727
728	return IRQ_HANDLED;
729}
730
731static const struct smp_ops xen_smp_ops __initconst = {
732	.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
733	.smp_prepare_cpus = xen_smp_prepare_cpus,
734	.smp_cpus_done = xen_smp_cpus_done,
735
736	.cpu_up = xen_cpu_up,
737	.cpu_die = xen_cpu_die,
738	.cpu_disable = xen_cpu_disable,
739	.play_dead = xen_play_dead,
740
741	.stop_other_cpus = xen_stop_other_cpus,
742	.smp_send_reschedule = xen_smp_send_reschedule,
743
744	.send_call_func_ipi = xen_smp_send_call_function_ipi,
745	.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
746};
747
748void __init xen_smp_init(void)
749{
750	smp_ops = xen_smp_ops;
751	xen_fill_possible_map();
752}
753
754static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
755{
756	native_smp_prepare_cpus(max_cpus);
757	WARN_ON(xen_smp_intr_init(0));
758
759	xen_init_lock_cpu(0);
760}
761
762static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
763{
764	int rc;
765
766	/*
767	 * This can happen if CPU was offlined earlier and
768	 * offlining timed out in common_cpu_die().
769	 */
770	if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
771		xen_smp_intr_free(cpu);
772		xen_uninit_lock_cpu(cpu);
773	}
774
775	/*
776	 * xen_smp_intr_init() needs to run before native_cpu_up()
777	 * so that IPI vectors are set up on the booting CPU before
778	 * it is marked online in native_cpu_up().
779	*/
780	rc = xen_smp_intr_init(cpu);
781	WARN_ON(rc);
782	if (!rc)
783		rc =  native_cpu_up(cpu, tidle);
784
785	/*
786	 * We must initialize the slowpath CPU kicker _after_ the native
787	 * path has executed. If we initialized it before none of the
788	 * unlocker IPI kicks would reach the booting CPU as the booting
789	 * CPU had not set itself 'online' in cpu_online_mask. That mask
790	 * is checked when IPIs are sent (on HVM at least).
791	 */
792	xen_init_lock_cpu(cpu);
793	return rc;
794}
795
796void __init xen_hvm_smp_init(void)
797{
798	if (!xen_have_vector_callback)
799		return;
800	smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
801	smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
802	smp_ops.cpu_up = xen_hvm_cpu_up;
803	smp_ops.cpu_die = xen_cpu_die;
804	smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
805	smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
806	smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;
807}
808