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15#include <linux/sched.h>
16#include <linux/err.h>
17#include <linux/slab.h>
18#include <linux/smp.h>
19
20#include <asm/paravirt.h>
21#include <asm/desc.h>
22#include <asm/pgtable.h>
23#include <asm/cpu.h>
24
25#include <xen/interface/xen.h>
26#include <xen/interface/vcpu.h>
27
28#include <asm/xen/interface.h>
29#include <asm/xen/hypercall.h>
30
31#include <xen/xen.h>
32#include <xen/page.h>
33#include <xen/events.h>
34
35#include "xen-ops.h"
36#include "mmu.h"
37
38cpumask_var_t xen_cpu_initialized_map;
39
40static DEFINE_PER_CPU(int, xen_resched_irq);
41static DEFINE_PER_CPU(int, xen_callfunc_irq);
42static DEFINE_PER_CPU(int, xen_callfuncsingle_irq);
43static DEFINE_PER_CPU(int, xen_debug_irq) = -1;
44
45static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
46static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
47
48
49
50
51
52
53static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
54{
55 inc_irq_stat(irq_resched_count);
56
57 return IRQ_HANDLED;
58}
59
60static __cpuinit void cpu_bringup(void)
61{
62 int cpu = smp_processor_id();
63
64 cpu_init();
65 touch_softlockup_watchdog();
66 preempt_disable();
67
68 xen_enable_sysenter();
69 xen_enable_syscall();
70
71 cpu = smp_processor_id();
72 smp_store_cpu_info(cpu);
73 cpu_data(cpu).x86_max_cores = 1;
74 set_cpu_sibling_map(cpu);
75
76 xen_setup_cpu_clockevents();
77
78 set_cpu_online(cpu, true);
79 percpu_write(cpu_state, CPU_ONLINE);
80 wmb();
81
82
83 local_irq_enable();
84
85 wmb();
86}
87
88static __cpuinit void cpu_bringup_and_idle(void)
89{
90 cpu_bringup();
91 cpu_idle();
92}
93
94static int xen_smp_intr_init(unsigned int cpu)
95{
96 int rc;
97 const char *resched_name, *callfunc_name, *debug_name;
98
99 resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
100 rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
101 cpu,
102 xen_reschedule_interrupt,
103 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
104 resched_name,
105 NULL);
106 if (rc < 0)
107 goto fail;
108 per_cpu(xen_resched_irq, cpu) = rc;
109
110 callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
111 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
112 cpu,
113 xen_call_function_interrupt,
114 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
115 callfunc_name,
116 NULL);
117 if (rc < 0)
118 goto fail;
119 per_cpu(xen_callfunc_irq, cpu) = rc;
120
121 debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
122 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
123 IRQF_DISABLED | IRQF_PERCPU | IRQF_NOBALANCING,
124 debug_name, NULL);
125 if (rc < 0)
126 goto fail;
127 per_cpu(xen_debug_irq, cpu) = rc;
128
129 callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
130 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
131 cpu,
132 xen_call_function_single_interrupt,
133 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
134 callfunc_name,
135 NULL);
136 if (rc < 0)
137 goto fail;
138 per_cpu(xen_callfuncsingle_irq, cpu) = rc;
139
140 return 0;
141
142 fail:
143 if (per_cpu(xen_resched_irq, cpu) >= 0)
144 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
145 if (per_cpu(xen_callfunc_irq, cpu) >= 0)
146 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
147 if (per_cpu(xen_debug_irq, cpu) >= 0)
148 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
149 if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0)
150 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu),
151 NULL);
152
153 return rc;
154}
155
156static void __init xen_fill_possible_map(void)
157{
158 int i, rc;
159
160 if (xen_initial_domain())
161 return;
162
163 for (i = 0; i < nr_cpu_ids; i++) {
164 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
165 if (rc >= 0) {
166 num_processors++;
167 set_cpu_possible(i, true);
168 }
169 }
170}
171
172static void __init xen_filter_cpu_maps(void)
173{
174 int i, rc;
175
176 if (!xen_initial_domain())
177 return;
178
179 num_processors = 0;
180 disabled_cpus = 0;
181 for (i = 0; i < nr_cpu_ids; i++) {
182 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
183 if (rc >= 0) {
184 num_processors++;
185 set_cpu_possible(i, true);
186 } else {
187 set_cpu_possible(i, false);
188 set_cpu_present(i, false);
189 }
190 }
191}
192
193static void __init xen_smp_prepare_boot_cpu(void)
194{
195 BUG_ON(smp_processor_id() != 0);
196 native_smp_prepare_boot_cpu();
197
198
199
200 make_lowmem_page_readwrite(xen_initial_gdt);
201
202 xen_filter_cpu_maps();
203 xen_setup_vcpu_info_placement();
204}
205
206static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
207{
208 unsigned cpu;
209
210 xen_init_lock_cpu(0);
211
212 smp_store_cpu_info(0);
213 cpu_data(0).x86_max_cores = 1;
214 set_cpu_sibling_map(0);
215
216 if (xen_smp_intr_init(0))
217 BUG();
218
219 if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
220 panic("could not allocate xen_cpu_initialized_map\n");
221
222 cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
223
224
225 while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
226 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
227 continue;
228 set_cpu_possible(cpu, false);
229 }
230
231 for_each_possible_cpu (cpu) {
232 struct task_struct *idle;
233
234 if (cpu == 0)
235 continue;
236
237 idle = fork_idle(cpu);
238 if (IS_ERR(idle))
239 panic("failed fork for CPU %d", cpu);
240
241 set_cpu_present(cpu, true);
242 }
243}
244
245static __cpuinit int
246cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
247{
248 struct vcpu_guest_context *ctxt;
249 struct desc_struct *gdt;
250 unsigned long gdt_mfn;
251
252 if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
253 return 0;
254
255 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
256 if (ctxt == NULL)
257 return -ENOMEM;
258
259 gdt = get_cpu_gdt_table(cpu);
260
261 ctxt->flags = VGCF_IN_KERNEL;
262 ctxt->user_regs.ds = __USER_DS;
263 ctxt->user_regs.es = __USER_DS;
264 ctxt->user_regs.ss = __KERNEL_DS;
265#ifdef CONFIG_X86_32
266 ctxt->user_regs.fs = __KERNEL_PERCPU;
267 ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
268#else
269 ctxt->gs_base_kernel = per_cpu_offset(cpu);
270#endif
271 ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
272 ctxt->user_regs.eflags = 0x1000;
273
274 memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
275
276 xen_copy_trap_info(ctxt->trap_ctxt);
277
278 ctxt->ldt_ents = 0;
279
280 BUG_ON((unsigned long)gdt & ~PAGE_MASK);
281
282 gdt_mfn = arbitrary_virt_to_mfn(gdt);
283 make_lowmem_page_readonly(gdt);
284 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
285
286 ctxt->gdt_frames[0] = gdt_mfn;
287 ctxt->gdt_ents = GDT_ENTRIES;
288
289 ctxt->user_regs.cs = __KERNEL_CS;
290 ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
291
292 ctxt->kernel_ss = __KERNEL_DS;
293 ctxt->kernel_sp = idle->thread.sp0;
294
295#ifdef CONFIG_X86_32
296 ctxt->event_callback_cs = __KERNEL_CS;
297 ctxt->failsafe_callback_cs = __KERNEL_CS;
298#endif
299 ctxt->event_callback_eip = (unsigned long)xen_hypervisor_callback;
300 ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
301
302 per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
303 ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
304
305 if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
306 BUG();
307
308 kfree(ctxt);
309 return 0;
310}
311
312static int __cpuinit xen_cpu_up(unsigned int cpu)
313{
314 struct task_struct *idle = idle_task(cpu);
315 int rc;
316
317 per_cpu(current_task, cpu) = idle;
318#ifdef CONFIG_X86_32
319 irq_ctx_init(cpu);
320#else
321 clear_tsk_thread_flag(idle, TIF_FORK);
322 per_cpu(kernel_stack, cpu) =
323 (unsigned long)task_stack_page(idle) -
324 KERNEL_STACK_OFFSET + THREAD_SIZE;
325#endif
326 xen_setup_runstate_info(cpu);
327 xen_setup_timer(cpu);
328 xen_init_lock_cpu(cpu);
329
330 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
331
332
333 per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
334
335 rc = cpu_initialize_context(cpu, idle);
336 if (rc)
337 return rc;
338
339 if (num_online_cpus() == 1)
340 alternatives_smp_switch(1);
341
342 rc = xen_smp_intr_init(cpu);
343 if (rc)
344 return rc;
345
346 rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
347 BUG_ON(rc);
348
349 while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
350 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
351 barrier();
352 }
353
354 return 0;
355}
356
357static void xen_smp_cpus_done(unsigned int max_cpus)
358{
359}
360
361#ifdef CONFIG_HOTPLUG_CPU
362static int xen_cpu_disable(void)
363{
364 unsigned int cpu = smp_processor_id();
365 if (cpu == 0)
366 return -EBUSY;
367
368 cpu_disable_common();
369
370 load_cr3(swapper_pg_dir);
371 return 0;
372}
373
374static void xen_cpu_die(unsigned int cpu)
375{
376 while (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
377 current->state = TASK_UNINTERRUPTIBLE;
378 schedule_timeout(HZ/10);
379 }
380 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
381 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
382 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
383 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
384 xen_uninit_lock_cpu(cpu);
385 xen_teardown_timer(cpu);
386
387 if (num_online_cpus() == 1)
388 alternatives_smp_switch(0);
389}
390
391static void __cpuinit xen_play_dead(void)
392{
393 play_dead_common();
394 HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
395 cpu_bringup();
396}
397
398#else
399static int xen_cpu_disable(void)
400{
401 return -ENOSYS;
402}
403
404static void xen_cpu_die(unsigned int cpu)
405{
406 BUG();
407}
408
409static void xen_play_dead(void)
410{
411 BUG();
412}
413
414#endif
415static void stop_self(void *v)
416{
417 int cpu = smp_processor_id();
418
419
420 load_cr3(swapper_pg_dir);
421
422
423 set_cpu_online(cpu, false);
424
425 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
426 BUG();
427}
428
429static void xen_stop_other_cpus(int wait)
430{
431 smp_call_function(stop_self, NULL, wait);
432}
433
434static void xen_smp_send_reschedule(int cpu)
435{
436 xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
437}
438
439static void xen_send_IPI_mask(const struct cpumask *mask,
440 enum ipi_vector vector)
441{
442 unsigned cpu;
443
444 for_each_cpu_and(cpu, mask, cpu_online_mask)
445 xen_send_IPI_one(cpu, vector);
446}
447
448static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
449{
450 int cpu;
451
452 xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
453
454
455 for_each_cpu(cpu, mask) {
456 if (xen_vcpu_stolen(cpu)) {
457 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
458 break;
459 }
460 }
461}
462
463static void xen_smp_send_call_function_single_ipi(int cpu)
464{
465 xen_send_IPI_mask(cpumask_of(cpu),
466 XEN_CALL_FUNCTION_SINGLE_VECTOR);
467}
468
469static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
470{
471 irq_enter();
472 generic_smp_call_function_interrupt();
473 inc_irq_stat(irq_call_count);
474 irq_exit();
475
476 return IRQ_HANDLED;
477}
478
479static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
480{
481 irq_enter();
482 generic_smp_call_function_single_interrupt();
483 inc_irq_stat(irq_call_count);
484 irq_exit();
485
486 return IRQ_HANDLED;
487}
488
489static const struct smp_ops xen_smp_ops __initdata = {
490 .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
491 .smp_prepare_cpus = xen_smp_prepare_cpus,
492 .smp_cpus_done = xen_smp_cpus_done,
493
494 .cpu_up = xen_cpu_up,
495 .cpu_die = xen_cpu_die,
496 .cpu_disable = xen_cpu_disable,
497 .play_dead = xen_play_dead,
498
499 .stop_other_cpus = xen_stop_other_cpus,
500 .smp_send_reschedule = xen_smp_send_reschedule,
501
502 .send_call_func_ipi = xen_smp_send_call_function_ipi,
503 .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
504};
505
506void __init xen_smp_init(void)
507{
508 smp_ops = xen_smp_ops;
509 xen_fill_possible_map();
510 xen_init_spinlocks();
511}
512
