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         per_cpu(kernel_stack, cpu) =
 445                 (unsigned long)task_stack_page(idle) -
 446                 KERNEL_STACK_OFFSET + THREAD_SIZE;
 447 #endif
 448         xen_setup_runstate_info(cpu);
 449         xen_setup_timer(cpu);
 450         xen_init_lock_cpu(cpu);
 451
 452         per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
 453
 454         /* make sure interrupts start blocked */
 455         per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
 456
 457         rc = cpu_initialize_context(cpu, idle);
 458         if (rc)
 459                 return rc;
 460
 461         if (num_online_cpus() == 1)
 462                 /* Just in case we booted with a single CPU. */
 463                 alternatives_enable_smp();
 464
 465         rc = xen_smp_intr_init(cpu);
 466         if (rc)
 467                 return rc;
 468
 469         rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
 470         BUG_ON(rc);
 471
 472         while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
 473                 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
 474                 barrier();
 475         }
 476
 477         return 0;
 478 }
 479
 480 static void xen_smp_cpus_done(unsigned int max_cpus)
 481 {
 482 }
 483
 484 #ifdef CONFIG_HOTPLUG_CPU
 485 static int xen_cpu_disable(void)
 486 {
 487         unsigned int cpu = smp_processor_id();
 488         if (cpu == 0)
 489                 return -EBUSY;
 490
 491         cpu_disable_common();
 492
 493         load_cr3(swapper_pg_dir);
 494         return 0;
 495 }
 496
 497 static void xen_cpu_die(unsigned int cpu)
 498 {
 499         while (xen_pv_domain() && HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
 500                 current->state = TASK_UNINTERRUPTIBLE;
 501                 schedule_timeout(HZ/10);
 502         }
 503         xen_smp_intr_free(cpu);
 504         xen_uninit_lock_cpu(cpu);
 505         xen_teardown_timer(cpu);
 506 }
 507
 508 static void xen_play_dead(void) /* used only with HOTPLUG_CPU */
 509 {
 510         play_dead_common();
 511         HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
 512         cpu_bringup();
 513         /*
 514          * commit 4b0c0f294 (tick: Cleanup NOHZ per cpu data on cpu down)
 515          * clears certain data that the cpu_idle loop (which called us
 516          * and that we return from) expects. The only way to get that
 517          * data back is to call:
 518          */
 519         tick_nohz_idle_enter();
 520 }
 521
 522 #else /* !CONFIG_HOTPLUG_CPU */
 523 static int xen_cpu_disable(void)
 524 {
 525         return -ENOSYS;
 526 }
 527
 528 static void xen_cpu_die(unsigned int cpu)
 529 {
 530         BUG();
 531 }
 532
 533 static void xen_play_dead(void)
 534 {
 535         BUG();
 536 }
 537
 538 #endif
 539 static void stop_self(void *v)
 540 {
 541         int cpu = smp_processor_id();
 542
 543         /* make sure we're not pinning something down */
 544         load_cr3(swapper_pg_dir);
 545         /* should set up a minimal gdt */
 546
 547         set_cpu_online(cpu, false);
 548
 549         HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
 550         BUG();
 551 }
 552
 553 static void xen_stop_other_cpus(int wait)
 554 {
 555         smp_call_function(stop_self, NULL, wait);
 556 }
 557
 558 static void xen_smp_send_reschedule(int cpu)
 559 {
 560         xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
 561 }
 562
 563 static void __xen_send_IPI_mask(const struct cpumask *mask,
 564                               int vector)
 565 {
 566         unsigned cpu;
 567
 568         for_each_cpu_and(cpu, mask, cpu_online_mask)
 569                 xen_send_IPI_one(cpu, vector);
 570 }
 571
 572 static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
 573 {
 574         int cpu;
 575
 576         __xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
 577
 578         /* Make sure other vcpus get a chance to run if they need to. */
 579         for_each_cpu(cpu, mask) {
 580                 if (xen_vcpu_stolen(cpu)) {
 581                         HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
 582                         break;
 583                 }
 584         }
 585 }
 586
 587 static void xen_smp_send_call_function_single_ipi(int cpu)
 588 {
 589         __xen_send_IPI_mask(cpumask_of(cpu),
 590                           XEN_CALL_FUNCTION_SINGLE_VECTOR);
 591 }
 592
 593 static inline int xen_map_vector(int vector)
 594 {
 595         int xen_vector;
 596
 597         switch (vector) {
 598         case RESCHEDULE_VECTOR:
 599                 xen_vector = XEN_RESCHEDULE_VECTOR;
 600                 break;
 601         case CALL_FUNCTION_VECTOR:
 602                 xen_vector = XEN_CALL_FUNCTION_VECTOR;
 603                 break;
 604         case CALL_FUNCTION_SINGLE_VECTOR:
 605                 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
 606                 break;
 607         case IRQ_WORK_VECTOR:
 608                 xen_vector = XEN_IRQ_WORK_VECTOR;
 609                 break;
 610 #ifdef CONFIG_X86_64
 611         case NMI_VECTOR:
 612         case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
 613                 xen_vector = XEN_NMI_VECTOR;
 614                 break;
 615 #endif
 616         default:
 617                 xen_vector = -1;
 618                 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
 619                         vector);
 620         }
 621
 622         return xen_vector;
 623 }
 624
 625 void xen_send_IPI_mask(const struct cpumask *mask,
 626                               int vector)
 627 {
 628         int xen_vector = xen_map_vector(vector);
 629
 630         if (xen_vector >= 0)
 631                 __xen_send_IPI_mask(mask, xen_vector);
 632 }
 633
 634 void xen_send_IPI_all(int vector)
 635 {
 636         int xen_vector = xen_map_vector(vector);
 637
 638         if (xen_vector >= 0)
 639                 __xen_send_IPI_mask(cpu_online_mask, xen_vector);
 640 }
 641
 642 void xen_send_IPI_self(int vector)
 643 {
 644         int xen_vector = xen_map_vector(vector);
 645
 646         if (xen_vector >= 0)
 647                 xen_send_IPI_one(smp_processor_id(), xen_vector);
 648 }
 649
 650 void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
 651                                 int vector)
 652 {
 653         unsigned cpu;
 654         unsigned int this_cpu = smp_processor_id();
 655         int xen_vector = xen_map_vector(vector);
 656
 657         if (!(num_online_cpus() > 1) || (xen_vector < 0))
 658                 return;
 659
 660         for_each_cpu_and(cpu, mask, cpu_online_mask) {
 661                 if (this_cpu == cpu)
 662                         continue;
 663
 664                 xen_send_IPI_one(cpu, xen_vector);
 665         }
 666 }
 667
 668 void xen_send_IPI_allbutself(int vector)
 669 {
 670         xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
 671 }
 672
 673 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
 674 {
 675         irq_enter();
 676         generic_smp_call_function_interrupt();
 677         inc_irq_stat(irq_call_count);
 678         irq_exit();
 679
 680         return IRQ_HANDLED;
 681 }
 682
 683 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
 684 {
 685         irq_enter();
 686         generic_smp_call_function_single_interrupt();
 687         inc_irq_stat(irq_call_count);
 688         irq_exit();
 689
 690         return IRQ_HANDLED;
 691 }
 692
 693 static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
 694 {
 695         irq_enter();
 696         irq_work_run();
 697         inc_irq_stat(apic_irq_work_irqs);
 698         irq_exit();
 699
 700         return IRQ_HANDLED;
 701 }
 702
 703 static const struct smp_ops xen_smp_ops __initconst = {
 704         .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
 705         .smp_prepare_cpus = xen_smp_prepare_cpus,
 706         .smp_cpus_done = xen_smp_cpus_done,
 707
 708         .cpu_up = xen_cpu_up,
 709         .cpu_die = xen_cpu_die,
 710         .cpu_disable = xen_cpu_disable,
 711         .play_dead = xen_play_dead,
 712
 713         .stop_other_cpus = xen_stop_other_cpus,
 714         .smp_send_reschedule = xen_smp_send_reschedule,
 715
 716         .send_call_func_ipi = xen_smp_send_call_function_ipi,
 717         .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
 718 };
 719
 720 void __init xen_smp_init(void)
 721 {
 722         smp_ops = xen_smp_ops;
 723         xen_fill_possible_map();
 724 }
 725
 726 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
 727 {
 728         native_smp_prepare_cpus(max_cpus);
 729         WARN_ON(xen_smp_intr_init(0));
 730
 731         xen_init_lock_cpu(0);
 732 }
 733
 734 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
 735 {
 736         int rc;
 737         /*
 738          * xen_smp_intr_init() needs to run before native_cpu_up()
 739          * so that IPI vectors are set up on the booting CPU before
 740          * it is marked online in native_cpu_up().
 741         */
 742         rc = xen_smp_intr_init(cpu);
 743         WARN_ON(rc);
 744         if (!rc)
 745                 rc =  native_cpu_up(cpu, tidle);
 746
 747         /*
 748          * We must initialize the slowpath CPU kicker _after_ the native
 749          * path has executed. If we initialized it before none of the
 750          * unlocker IPI kicks would reach the booting CPU as the booting
 751          * CPU had not set itself 'online' in cpu_online_mask. That mask
 752          * is checked when IPIs are sent (on HVM at least).
 753          */
 754         xen_init_lock_cpu(cpu);
 755         return rc;
 756 }
 757
 758 static void xen_hvm_cpu_die(unsigned int cpu)
 759 {
 760         xen_cpu_die(cpu);
 761         native_cpu_die(cpu);
 762 }
 763
 764 void __init xen_hvm_smp_init(void)
 765 {
 766         if (!xen_have_vector_callback)
 767                 return;
 768         smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
 769         smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
 770         smp_ops.cpu_up = xen_hvm_cpu_up;
 771         smp_ops.cpu_die = xen_hvm_cpu_die;
 772         smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
 773         smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
 774         smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;
 775 }