iwlwifi: pcie: fix polling in various places
[cascardo/linux.git] / arch / x86 / xen / smp.c
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
30 #include <asm/xen/interface.h>
31 #include <asm/xen/hypercall.h>
32
33 #include <xen/xen.h>
34 #include <xen/page.h>
35 #include <xen/events.h>
36
37 #include <xen/hvc-console.h>
38 #include "xen-ops.h"
39 #include "mmu.h"
40
41 cpumask_var_t xen_cpu_initialized_map;
42
43 struct xen_common_irq {
44         int irq;
45         char *name;
46 };
47 static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
48 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
49 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
50 static DEFINE_PER_CPU(struct xen_common_irq, xen_irq_work) = { .irq = -1 };
51 static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
52
53 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
54 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
55 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id);
56
57 /*
58  * Reschedule call back.
59  */
60 static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
61 {
62         inc_irq_stat(irq_resched_count);
63         scheduler_ipi();
64
65         return IRQ_HANDLED;
66 }
67
68 static void cpu_bringup(void)
69 {
70         int cpu;
71
72         cpu_init();
73         touch_softlockup_watchdog();
74         preempt_disable();
75
76         /* PVH runs in ring 0 and allows us to do native syscalls. Yay! */
77         if (!xen_feature(XENFEAT_supervisor_mode_kernel)) {
78                 xen_enable_sysenter();
79                 xen_enable_syscall();
80         }
81         cpu = smp_processor_id();
82         smp_store_cpu_info(cpu);
83         cpu_data(cpu).x86_max_cores = 1;
84         set_cpu_sibling_map(cpu);
85
86         xen_setup_cpu_clockevents();
87
88         notify_cpu_starting(cpu);
89
90         set_cpu_online(cpu, true);
91
92         this_cpu_write(cpu_state, CPU_ONLINE);
93
94         wmb();
95
96         /* We can take interrupts now: we're officially "up". */
97         local_irq_enable();
98
99         wmb();                  /* make sure everything is out */
100 }
101
102 /* Note: cpu parameter is only relevant for PVH */
103 static void cpu_bringup_and_idle(int cpu)
104 {
105 #ifdef CONFIG_X86_64
106         if (xen_feature(XENFEAT_auto_translated_physmap) &&
107             xen_feature(XENFEAT_supervisor_mode_kernel))
108                 xen_pvh_secondary_vcpu_init(cpu);
109 #endif
110         cpu_bringup();
111         cpu_startup_entry(CPUHP_ONLINE);
112 }
113
114 static void xen_smp_intr_free(unsigned int cpu)
115 {
116         if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
117                 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
118                 per_cpu(xen_resched_irq, cpu).irq = -1;
119                 kfree(per_cpu(xen_resched_irq, cpu).name);
120                 per_cpu(xen_resched_irq, cpu).name = NULL;
121         }
122         if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
123                 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
124                 per_cpu(xen_callfunc_irq, cpu).irq = -1;
125                 kfree(per_cpu(xen_callfunc_irq, cpu).name);
126                 per_cpu(xen_callfunc_irq, cpu).name = NULL;
127         }
128         if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
129                 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
130                 per_cpu(xen_debug_irq, cpu).irq = -1;
131                 kfree(per_cpu(xen_debug_irq, cpu).name);
132                 per_cpu(xen_debug_irq, cpu).name = NULL;
133         }
134         if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
135                 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
136                                        NULL);
137                 per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
138                 kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
139                 per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
140         }
141         if (xen_hvm_domain())
142                 return;
143
144         if (per_cpu(xen_irq_work, cpu).irq >= 0) {
145                 unbind_from_irqhandler(per_cpu(xen_irq_work, cpu).irq, NULL);
146                 per_cpu(xen_irq_work, cpu).irq = -1;
147                 kfree(per_cpu(xen_irq_work, cpu).name);
148                 per_cpu(xen_irq_work, cpu).name = NULL;
149         }
150 };
151 static int xen_smp_intr_init(unsigned int cpu)
152 {
153         int rc;
154         char *resched_name, *callfunc_name, *debug_name;
155
156         resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
157         rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
158                                     cpu,
159                                     xen_reschedule_interrupt,
160                                     IRQF_PERCPU|IRQF_NOBALANCING,
161                                     resched_name,
162                                     NULL);
163         if (rc < 0)
164                 goto fail;
165         per_cpu(xen_resched_irq, cpu).irq = rc;
166         per_cpu(xen_resched_irq, cpu).name = resched_name;
167
168         callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
169         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
170                                     cpu,
171                                     xen_call_function_interrupt,
172                                     IRQF_PERCPU|IRQF_NOBALANCING,
173                                     callfunc_name,
174                                     NULL);
175         if (rc < 0)
176                 goto fail;
177         per_cpu(xen_callfunc_irq, cpu).irq = rc;
178         per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
179
180         debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
181         rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
182                                      IRQF_PERCPU | IRQF_NOBALANCING,
183                                      debug_name, NULL);
184         if (rc < 0)
185                 goto fail;
186         per_cpu(xen_debug_irq, cpu).irq = rc;
187         per_cpu(xen_debug_irq, cpu).name = debug_name;
188
189         callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
190         rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
191                                     cpu,
192                                     xen_call_function_single_interrupt,
193                                     IRQF_PERCPU|IRQF_NOBALANCING,
194                                     callfunc_name,
195                                     NULL);
196         if (rc < 0)
197                 goto fail;
198         per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
199         per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
200
201         /*
202          * The IRQ worker on PVHVM goes through the native path and uses the
203          * IPI mechanism.
204          */
205         if (xen_hvm_domain())
206                 return 0;
207
208         callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu);
209         rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR,
210                                     cpu,
211                                     xen_irq_work_interrupt,
212                                     IRQF_PERCPU|IRQF_NOBALANCING,
213                                     callfunc_name,
214                                     NULL);
215         if (rc < 0)
216                 goto fail;
217         per_cpu(xen_irq_work, cpu).irq = rc;
218         per_cpu(xen_irq_work, cpu).name = callfunc_name;
219
220         return 0;
221
222  fail:
223         xen_smp_intr_free(cpu);
224         return rc;
225 }
226
227 static void __init xen_fill_possible_map(void)
228 {
229         int i, rc;
230
231         if (xen_initial_domain())
232                 return;
233
234         for (i = 0; i < nr_cpu_ids; i++) {
235                 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
236                 if (rc >= 0) {
237                         num_processors++;
238                         set_cpu_possible(i, true);
239                 }
240         }
241 }
242
243 static void __init xen_filter_cpu_maps(void)
244 {
245         int i, rc;
246         unsigned int subtract = 0;
247
248         if (!xen_initial_domain())
249                 return;
250
251         num_processors = 0;
252         disabled_cpus = 0;
253         for (i = 0; i < nr_cpu_ids; i++) {
254                 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
255                 if (rc >= 0) {
256                         num_processors++;
257                         set_cpu_possible(i, true);
258                 } else {
259                         set_cpu_possible(i, false);
260                         set_cpu_present(i, false);
261                         subtract++;
262                 }
263         }
264 #ifdef CONFIG_HOTPLUG_CPU
265         /* This is akin to using 'nr_cpus' on the Linux command line.
266          * Which is OK as when we use 'dom0_max_vcpus=X' we can only
267          * have up to X, while nr_cpu_ids is greater than X. This
268          * normally is not a problem, except when CPU hotplugging
269          * is involved and then there might be more than X CPUs
270          * in the guest - which will not work as there is no
271          * hypercall to expand the max number of VCPUs an already
272          * running guest has. So cap it up to X. */
273         if (subtract)
274                 nr_cpu_ids = nr_cpu_ids - subtract;
275 #endif
276
277 }
278
279 static void __init xen_smp_prepare_boot_cpu(void)
280 {
281         BUG_ON(smp_processor_id() != 0);
282         native_smp_prepare_boot_cpu();
283
284         if (xen_pv_domain()) {
285                 if (!xen_feature(XENFEAT_writable_page_tables))
286                         /* We've switched to the "real" per-cpu gdt, so make
287                          * sure the old memory can be recycled. */
288                         make_lowmem_page_readwrite(xen_initial_gdt);
289
290 #ifdef CONFIG_X86_32
291                 /*
292                  * Xen starts us with XEN_FLAT_RING1_DS, but linux code
293                  * expects __USER_DS
294                  */
295                 loadsegment(ds, __USER_DS);
296                 loadsegment(es, __USER_DS);
297 #endif
298
299                 xen_filter_cpu_maps();
300                 xen_setup_vcpu_info_placement();
301         }
302         /*
303          * The alternative logic (which patches the unlock/lock) runs before
304          * the smp bootup up code is activated. Hence we need to set this up
305          * the core kernel is being patched. Otherwise we will have only
306          * modules patched but not core code.
307          */
308         xen_init_spinlocks();
309 }
310
311 static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
312 {
313         unsigned cpu;
314         unsigned int i;
315
316         if (skip_ioapic_setup) {
317                 char *m = (max_cpus == 0) ?
318                         "The nosmp parameter is incompatible with Xen; " \
319                         "use Xen dom0_max_vcpus=1 parameter" :
320                         "The noapic parameter is incompatible with Xen";
321
322                 xen_raw_printk(m);
323                 panic(m);
324         }
325         xen_init_lock_cpu(0);
326
327         smp_store_boot_cpu_info();
328         cpu_data(0).x86_max_cores = 1;
329
330         for_each_possible_cpu(i) {
331                 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
332                 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
333                 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
334         }
335         set_cpu_sibling_map(0);
336
337         if (xen_smp_intr_init(0))
338                 BUG();
339
340         if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
341                 panic("could not allocate xen_cpu_initialized_map\n");
342
343         cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
344
345         /* Restrict the possible_map according to max_cpus. */
346         while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
347                 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
348                         continue;
349                 set_cpu_possible(cpu, false);
350         }
351
352         for_each_possible_cpu(cpu)
353                 set_cpu_present(cpu, true);
354 }
355
356 static int
357 cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
358 {
359         struct vcpu_guest_context *ctxt;
360         struct desc_struct *gdt;
361         unsigned long gdt_mfn;
362
363         if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
364                 return 0;
365
366         ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
367         if (ctxt == NULL)
368                 return -ENOMEM;
369
370         gdt = get_cpu_gdt_table(cpu);
371
372 #ifdef CONFIG_X86_32
373         /* Note: PVH is not yet supported on x86_32. */
374         ctxt->user_regs.fs = __KERNEL_PERCPU;
375         ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
376 #endif
377         ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
378
379         memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
380
381         if (!xen_feature(XENFEAT_auto_translated_physmap)) {
382                 ctxt->flags = VGCF_IN_KERNEL;
383                 ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
384                 ctxt->user_regs.ds = __USER_DS;
385                 ctxt->user_regs.es = __USER_DS;
386                 ctxt->user_regs.ss = __KERNEL_DS;
387
388                 xen_copy_trap_info(ctxt->trap_ctxt);
389
390                 ctxt->ldt_ents = 0;
391
392                 BUG_ON((unsigned long)gdt & ~PAGE_MASK);
393
394                 gdt_mfn = arbitrary_virt_to_mfn(gdt);
395                 make_lowmem_page_readonly(gdt);
396                 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
397
398                 ctxt->gdt_frames[0] = gdt_mfn;
399                 ctxt->gdt_ents      = GDT_ENTRIES;
400
401                 ctxt->kernel_ss = __KERNEL_DS;
402                 ctxt->kernel_sp = idle->thread.sp0;
403
404 #ifdef CONFIG_X86_32
405                 ctxt->event_callback_cs     = __KERNEL_CS;
406                 ctxt->failsafe_callback_cs  = __KERNEL_CS;
407 #else
408                 ctxt->gs_base_kernel = per_cpu_offset(cpu);
409 #endif
410                 ctxt->event_callback_eip    =
411                                         (unsigned long)xen_hypervisor_callback;
412                 ctxt->failsafe_callback_eip =
413                                         (unsigned long)xen_failsafe_callback;
414                 ctxt->user_regs.cs = __KERNEL_CS;
415                 per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
416 #ifdef CONFIG_X86_32
417         }
418 #else
419         } else
420                 /* N.B. The user_regs.eip (cpu_bringup_and_idle) is called with
421                  * %rdi having the cpu number - which means are passing in
422                  * as the first parameter the cpu. Subtle!
423                  */
424                 ctxt->user_regs.rdi = cpu;
425 #endif
426         ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
427         ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
428         if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
429                 BUG();
430
431         kfree(ctxt);
432         return 0;
433 }
434
435 static int xen_cpu_up(unsigned int cpu, struct task_struct *idle)
436 {
437         int rc;
438
439         per_cpu(current_task, cpu) = idle;
440 #ifdef CONFIG_X86_32
441         irq_ctx_init(cpu);
442 #else
443         clear_tsk_thread_flag(idle, TIF_FORK);
444 #endif
445         per_cpu(kernel_stack, cpu) =
446                 (unsigned long)task_stack_page(idle) -
447                 KERNEL_STACK_OFFSET + THREAD_SIZE;
448
449         xen_setup_runstate_info(cpu);
450         xen_setup_timer(cpu);
451         xen_init_lock_cpu(cpu);
452
453         per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
454
455         /* make sure interrupts start blocked */
456         per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
457
458         rc = cpu_initialize_context(cpu, idle);
459         if (rc)
460                 return rc;
461
462         if (num_online_cpus() == 1)
463                 /* Just in case we booted with a single CPU. */
464                 alternatives_enable_smp();
465
466         rc = xen_smp_intr_init(cpu);
467         if (rc)
468                 return rc;
469
470         rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
471         BUG_ON(rc);
472
473         while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
474                 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
475                 barrier();
476         }
477
478         return 0;
479 }
480
481 static void xen_smp_cpus_done(unsigned int max_cpus)
482 {
483 }
484
485 #ifdef CONFIG_HOTPLUG_CPU
486 static int xen_cpu_disable(void)
487 {
488         unsigned int cpu = smp_processor_id();
489         if (cpu == 0)
490                 return -EBUSY;
491
492         cpu_disable_common();
493
494         load_cr3(swapper_pg_dir);
495         return 0;
496 }
497
498 static void xen_cpu_die(unsigned int cpu)
499 {
500         while (xen_pv_domain() && HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
501                 current->state = TASK_UNINTERRUPTIBLE;
502                 schedule_timeout(HZ/10);
503         }
504         xen_smp_intr_free(cpu);
505         xen_uninit_lock_cpu(cpu);
506         xen_teardown_timer(cpu);
507 }
508
509 static void xen_play_dead(void) /* used only with HOTPLUG_CPU */
510 {
511         play_dead_common();
512         HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
513         cpu_bringup();
514         /*
515          * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down)
516          * clears certain data that the cpu_idle loop (which called us
517          * and that we return from) expects. The only way to get that
518          * data back is to call:
519          */
520         tick_nohz_idle_enter();
521 }
522
523 #else /* !CONFIG_HOTPLUG_CPU */
524 static int xen_cpu_disable(void)
525 {
526         return -ENOSYS;
527 }
528
529 static void xen_cpu_die(unsigned int cpu)
530 {
531         BUG();
532 }
533
534 static void xen_play_dead(void)
535 {
536         BUG();
537 }
538
539 #endif
540 static void stop_self(void *v)
541 {
542         int cpu = smp_processor_id();
543
544         /* make sure we're not pinning something down */
545         load_cr3(swapper_pg_dir);
546         /* should set up a minimal gdt */
547
548         set_cpu_online(cpu, false);
549
550         HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
551         BUG();
552 }
553
554 static void xen_stop_other_cpus(int wait)
555 {
556         smp_call_function(stop_self, NULL, wait);
557 }
558
559 static void xen_smp_send_reschedule(int cpu)
560 {
561         xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
562 }
563
564 static void __xen_send_IPI_mask(const struct cpumask *mask,
565                               int vector)
566 {
567         unsigned cpu;
568
569         for_each_cpu_and(cpu, mask, cpu_online_mask)
570                 xen_send_IPI_one(cpu, vector);
571 }
572
573 static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
574 {
575         int cpu;
576
577         __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
578
579         /* Make sure other vcpus get a chance to run if they need to. */
580         for_each_cpu(cpu, mask) {
581                 if (xen_vcpu_stolen(cpu)) {
582                         HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
583                         break;
584                 }
585         }
586 }
587
588 static void xen_smp_send_call_function_single_ipi(int cpu)
589 {
590         __xen_send_IPI_mask(cpumask_of(cpu),
591                           XEN_CALL_FUNCTION_SINGLE_VECTOR);
592 }
593
594 static inline int xen_map_vector(int vector)
595 {
596         int xen_vector;
597
598         switch (vector) {
599         case RESCHEDULE_VECTOR:
600                 xen_vector = XEN_RESCHEDULE_VECTOR;
601                 break;
602         case CALL_FUNCTION_VECTOR:
603                 xen_vector = XEN_CALL_FUNCTION_VECTOR;
604                 break;
605         case CALL_FUNCTION_SINGLE_VECTOR:
606                 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
607                 break;
608         case IRQ_WORK_VECTOR:
609                 xen_vector = XEN_IRQ_WORK_VECTOR;
610                 break;
611 #ifdef CONFIG_X86_64
612         case NMI_VECTOR:
613         case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
614                 xen_vector = XEN_NMI_VECTOR;
615                 break;
616 #endif
617         default:
618                 xen_vector = -1;
619                 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
620                         vector);
621         }
622
623         return xen_vector;
624 }
625
626 void xen_send_IPI_mask(const struct cpumask *mask,
627                               int vector)
628 {
629         int xen_vector = xen_map_vector(vector);
630
631         if (xen_vector >= 0)
632                 __xen_send_IPI_mask(mask, xen_vector);
633 }
634
635 void xen_send_IPI_all(int vector)
636 {
637         int xen_vector = xen_map_vector(vector);
638
639         if (xen_vector >= 0)
640                 __xen_send_IPI_mask(cpu_online_mask, xen_vector);
641 }
642
643 void xen_send_IPI_self(int vector)
644 {
645         int xen_vector = xen_map_vector(vector);
646
647         if (xen_vector >= 0)
648                 xen_send_IPI_one(smp_processor_id(), xen_vector);
649 }
650
651 void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
652                                 int vector)
653 {
654         unsigned cpu;
655         unsigned int this_cpu = smp_processor_id();
656         int xen_vector = xen_map_vector(vector);
657
658         if (!(num_online_cpus() > 1) || (xen_vector < 0))
659                 return;
660
661         for_each_cpu_and(cpu, mask, cpu_online_mask) {
662                 if (this_cpu == cpu)
663                         continue;
664
665                 xen_send_IPI_one(cpu, xen_vector);
666         }
667 }
668
669 void xen_send_IPI_allbutself(int vector)
670 {
671         xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
672 }
673
674 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
675 {
676         irq_enter();
677         generic_smp_call_function_interrupt();
678         inc_irq_stat(irq_call_count);
679         irq_exit();
680
681         return IRQ_HANDLED;
682 }
683
684 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
685 {
686         irq_enter();
687         generic_smp_call_function_single_interrupt();
688         inc_irq_stat(irq_call_count);
689         irq_exit();
690
691         return IRQ_HANDLED;
692 }
693
694 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
695 {
696         irq_enter();
697         irq_work_run();
698         inc_irq_stat(apic_irq_work_irqs);
699         irq_exit();
700
701         return IRQ_HANDLED;
702 }
703
704 static const struct smp_ops xen_smp_ops __initconst = {
705         .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
706         .smp_prepare_cpus = xen_smp_prepare_cpus,
707         .smp_cpus_done = xen_smp_cpus_done,
708
709         .cpu_up = xen_cpu_up,
710         .cpu_die = xen_cpu_die,
711         .cpu_disable = xen_cpu_disable,
712         .play_dead = xen_play_dead,
713
714         .stop_other_cpus = xen_stop_other_cpus,
715         .smp_send_reschedule = xen_smp_send_reschedule,
716
717         .send_call_func_ipi = xen_smp_send_call_function_ipi,
718         .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
719 };
720
721 void __init xen_smp_init(void)
722 {
723         smp_ops = xen_smp_ops;
724         xen_fill_possible_map();
725 }
726
727 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
728 {
729         native_smp_prepare_cpus(max_cpus);
730         WARN_ON(xen_smp_intr_init(0));
731
732         xen_init_lock_cpu(0);
733 }
734
735 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
736 {
737         int rc;
738         /*
739          * xen_smp_intr_init() needs to run before native_cpu_up()
740          * so that IPI vectors are set up on the booting CPU before
741          * it is marked online in native_cpu_up().
742         */
743         rc = xen_smp_intr_init(cpu);
744         WARN_ON(rc);
745         if (!rc)
746                 rc =  native_cpu_up(cpu, tidle);
747
748         /*
749          * We must initialize the slowpath CPU kicker _after_ the native
750          * path has executed. If we initialized it before none of the
751          * unlocker IPI kicks would reach the booting CPU as the booting
752          * CPU had not set itself 'online' in cpu_online_mask. That mask
753          * is checked when IPIs are sent (on HVM at least).
754          */
755         xen_init_lock_cpu(cpu);
756         return rc;
757 }
758
759 static void xen_hvm_cpu_die(unsigned int cpu)
760 {
761         xen_cpu_die(cpu);
762         native_cpu_die(cpu);
763 }
764
765 void __init xen_hvm_smp_init(void)
766 {
767         if (!xen_have_vector_callback)
768                 return;
769         smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
770         smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
771         smp_ops.cpu_up = xen_hvm_cpu_up;
772         smp_ops.cpu_die = xen_hvm_cpu_die;
773         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
774         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
775         smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;
776 }