arch/x86/kvm/irq_comm.c

   1 /*
   2  * irq_comm.c: Common API for in kernel interrupt controller
   3  * Copyright (c) 2007, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  16  * Place - Suite 330, Boston, MA 02111-1307 USA.
  17  * Authors:
  18  *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
  19  *
  20  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  21  */
  22
  23 #include <linux/kvm_host.h>
  24 #include <linux/slab.h>
  25 #include <linux/export.h>
  26 #include <trace/events/kvm.h>
  27
  28 #include <asm/msidef.h>
  29
  30 #include "irq.h"
  31
  32 #include "ioapic.h"
  33
  34 #include "lapic.h"
  35
  36 #include "hyperv.h"
  37
  38 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
  39                            struct kvm *kvm, int irq_source_id, int level,
  40                            bool line_status)
  41 {
  42         struct kvm_pic *pic = pic_irqchip(kvm);
  43         return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
  44 }
  45
  46 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
  47                               struct kvm *kvm, int irq_source_id, int level,
  48                               bool line_status)
  49 {
  50         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
  51         return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
  52                                 line_status);
  53 }
  54
  55 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
  56                 struct kvm_lapic_irq *irq, unsigned long *dest_map)
  57 {
  58         int i, r = -1;
  59         struct kvm_vcpu *vcpu, *lowest = NULL;
  60
  61         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
  62                         kvm_lowest_prio_delivery(irq)) {
  63                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
  64                 irq->delivery_mode = APIC_DM_FIXED;
  65         }
  66
  67         if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
  68                 return r;
  69
  70         kvm_for_each_vcpu(i, vcpu, kvm) {
  71                 if (!kvm_apic_present(vcpu))
  72                         continue;
  73
  74                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
  75                                         irq->dest_id, irq->dest_mode))
  76                         continue;
  77
  78                 if (!kvm_lowest_prio_delivery(irq)) {
  79                         if (r < 0)
  80                                 r = 0;
  81                         r += kvm_apic_set_irq(vcpu, irq, dest_map);
  82                 } else if (kvm_lapic_enabled(vcpu)) {
  83                         if (!lowest)
  84                                 lowest = vcpu;
  85                         else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
  86                                 lowest = vcpu;
  87                 }
  88         }
  89
  90         if (lowest)
  91                 r = kvm_apic_set_irq(lowest, irq, dest_map);
  92
  93         return r;
  94 }
  95
  96 void kvm_set_msi_irq(struct kvm_kernel_irq_routing_entry *e,
  97                      struct kvm_lapic_irq *irq)
  98 {
  99         trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
 100
 101         irq->dest_id = (e->msi.address_lo &
 102                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
 103         irq->vector = (e->msi.data &
 104                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
 105         irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
 106         irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
 107         irq->delivery_mode = e->msi.data & 0x700;
 108         irq->msi_redir_hint = ((e->msi.address_lo
 109                 & MSI_ADDR_REDIRECTION_LOWPRI) > 0);
 110         irq->level = 1;
 111         irq->shorthand = 0;
 112 }
 113 EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
 114
 115 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 116                 struct kvm *kvm, int irq_source_id, int level, bool line_status)
 117 {
 118         struct kvm_lapic_irq irq;
 119
 120         if (!level)
 121                 return -1;
 122
 123         kvm_set_msi_irq(e, &irq);
 124
 125         return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
 126 }
 127
 128
 129 int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 130                               struct kvm *kvm, int irq_source_id, int level,
 131                               bool line_status)
 132 {
 133         struct kvm_lapic_irq irq;
 134         int r;
 135
 136         if (unlikely(e->type != KVM_IRQ_ROUTING_MSI))
 137                 return -EWOULDBLOCK;
 138
 139         kvm_set_msi_irq(e, &irq);
 140
 141         if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
 142                 return r;
 143         else
 144                 return -EWOULDBLOCK;
 145 }
 146
 147 int kvm_request_irq_source_id(struct kvm *kvm)
 148 {
 149         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
 150         int irq_source_id;
 151
 152         mutex_lock(&kvm->irq_lock);
 153         irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
 154
 155         if (irq_source_id >= BITS_PER_LONG) {
 156                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 157                 irq_source_id = -EFAULT;
 158                 goto unlock;
 159         }
 160
 161         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 162         ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
 163         set_bit(irq_source_id, bitmap);
 164 unlock:
 165         mutex_unlock(&kvm->irq_lock);
 166
 167         return irq_source_id;
 168 }
 169
 170 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 171 {
 172         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 173         ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
 174
 175         mutex_lock(&kvm->irq_lock);
 176         if (irq_source_id < 0 ||
 177             irq_source_id >= BITS_PER_LONG) {
 178                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 179                 goto unlock;
 180         }
 181         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
 182         if (!ioapic_in_kernel(kvm))
 183                 goto unlock;
 184
 185         kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
 186         kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id);
 187 unlock:
 188         mutex_unlock(&kvm->irq_lock);
 189 }
 190
 191 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 192                                     struct kvm_irq_mask_notifier *kimn)
 193 {
 194         mutex_lock(&kvm->irq_lock);
 195         kimn->irq = irq;
 196         hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
 197         mutex_unlock(&kvm->irq_lock);
 198 }
 199
 200 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
 201                                       struct kvm_irq_mask_notifier *kimn)
 202 {
 203         mutex_lock(&kvm->irq_lock);
 204         hlist_del_rcu(&kimn->link);
 205         mutex_unlock(&kvm->irq_lock);
 206         synchronize_srcu(&kvm->irq_srcu);
 207 }
 208
 209 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
 210                              bool mask)
 211 {
 212         struct kvm_irq_mask_notifier *kimn;
 213         int idx, gsi;
 214
 215         idx = srcu_read_lock(&kvm->irq_srcu);
 216         gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
 217         if (gsi != -1)
 218                 hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
 219                         if (kimn->irq == gsi)
 220                                 kimn->func(kimn, mask);
 221         srcu_read_unlock(&kvm->irq_srcu, idx);
 222 }
 223
 224 static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
 225                     struct kvm *kvm, int irq_source_id, int level,
 226                     bool line_status)
 227 {
 228         if (!level)
 229                 return -1;
 230
 231         return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
 232 }
 233
 234 int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e,
 235                           const struct kvm_irq_routing_entry *ue)
 236 {
 237         int r = -EINVAL;
 238         int delta;
 239         unsigned max_pin;
 240
 241         switch (ue->type) {
 242         case KVM_IRQ_ROUTING_IRQCHIP:
 243                 delta = 0;
 244                 switch (ue->u.irqchip.irqchip) {
 245                 case KVM_IRQCHIP_PIC_MASTER:
 246                         e->set = kvm_set_pic_irq;
 247                         max_pin = PIC_NUM_PINS;
 248                         break;
 249                 case KVM_IRQCHIP_PIC_SLAVE:
 250                         e->set = kvm_set_pic_irq;
 251                         max_pin = PIC_NUM_PINS;
 252                         delta = 8;
 253                         break;
 254                 case KVM_IRQCHIP_IOAPIC:
 255                         max_pin = KVM_IOAPIC_NUM_PINS;
 256                         e->set = kvm_set_ioapic_irq;
 257                         break;
 258                 default:
 259                         goto out;
 260                 }
 261                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
 262                 e->irqchip.pin = ue->u.irqchip.pin + delta;
 263                 if (e->irqchip.pin >= max_pin)
 264                         goto out;
 265                 break;
 266         case KVM_IRQ_ROUTING_MSI:
 267                 e->set = kvm_set_msi;
 268                 e->msi.address_lo = ue->u.msi.address_lo;
 269                 e->msi.address_hi = ue->u.msi.address_hi;
 270                 e->msi.data = ue->u.msi.data;
 271                 break;
 272         case KVM_IRQ_ROUTING_HV_SINT:
 273                 e->set = kvm_hv_set_sint;
 274                 e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
 275                 e->hv_sint.sint = ue->u.hv_sint.sint;
 276                 break;
 277         default:
 278                 goto out;
 279         }
 280
 281         r = 0;
 282 out:
 283         return r;
 284 }
 285
 286 bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
 287                              struct kvm_vcpu **dest_vcpu)
 288 {
 289         int i, r = 0;
 290         struct kvm_vcpu *vcpu;
 291
 292         if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
 293                 return true;
 294
 295         kvm_for_each_vcpu(i, vcpu, kvm) {
 296                 if (!kvm_apic_present(vcpu))
 297                         continue;
 298
 299                 if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
 300                                         irq->dest_id, irq->dest_mode))
 301                         continue;
 302
 303                 if (++r == 2)
 304                         return false;
 305
 306                 *dest_vcpu = vcpu;
 307         }
 308
 309         return r == 1;
 310 }
 311 EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
 312
 313 #define IOAPIC_ROUTING_ENTRY(irq) \
 314         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 315           .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
 316 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 317
 318 #define PIC_ROUTING_ENTRY(irq) \
 319         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 320           .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
 321 #define ROUTING_ENTRY2(irq) \
 322         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
 323
 324 static const struct kvm_irq_routing_entry default_routing[] = {
 325         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
 326         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
 327         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
 328         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
 329         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
 330         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
 331         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
 332         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
 333         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
 334         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
 335         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
 336         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
 337 };
 338
 339 int kvm_setup_default_irq_routing(struct kvm *kvm)
 340 {
 341         return kvm_set_irq_routing(kvm, default_routing,
 342                                    ARRAY_SIZE(default_routing), 0);
 343 }
 344
 345 static const struct kvm_irq_routing_entry empty_routing[] = {};
 346
 347 int kvm_setup_empty_irq_routing(struct kvm *kvm)
 348 {
 349         return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
 350 }
 351
 352 void kvm_arch_post_irq_routing_update(struct kvm *kvm)
 353 {
 354         if (ioapic_in_kernel(kvm) || !irqchip_in_kernel(kvm))
 355                 return;
 356         kvm_make_scan_ioapic_request(kvm);
 357 }
 358
 359 void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
 360                             ulong *ioapic_handled_vectors)
 361 {
 362         struct kvm *kvm = vcpu->kvm;
 363         struct kvm_kernel_irq_routing_entry *entry;
 364         struct kvm_irq_routing_table *table;
 365         u32 i, nr_ioapic_pins;
 366         int idx;
 367
 368         /* kvm->irq_routing must be read after clearing
 369          * KVM_SCAN_IOAPIC. */
 370         smp_mb();
 371         idx = srcu_read_lock(&kvm->irq_srcu);
 372         table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
 373         nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
 374                                kvm->arch.nr_reserved_ioapic_pins);
 375         for (i = 0; i < nr_ioapic_pins; ++i) {
 376                 hlist_for_each_entry(entry, &table->map[i], link) {
 377                         u32 dest_id, dest_mode;
 378                         bool level;
 379
 380                         if (entry->type != KVM_IRQ_ROUTING_MSI)
 381                                 continue;
 382                         dest_id = (entry->msi.address_lo >> 12) & 0xff;
 383                         dest_mode = (entry->msi.address_lo >> 2) & 0x1;
 384                         level = entry->msi.data & MSI_DATA_TRIGGER_LEVEL;
 385                         if (level && kvm_apic_match_dest(vcpu, NULL, 0,
 386                                                 dest_id, dest_mode)) {
 387                                 u32 vector = entry->msi.data & 0xff;
 388
 389                                 __set_bit(vector,
 390                                           ioapic_handled_vectors);
 391                         }
 392                 }
 393         }
 394         srcu_read_unlock(&kvm->irq_srcu, idx);
 395 }
 396
 397 int kvm_arch_set_irq(struct kvm_kernel_irq_routing_entry *irq, struct kvm *kvm,
 398                      int irq_source_id, int level, bool line_status)
 399 {
 400         switch (irq->type) {
 401         case KVM_IRQ_ROUTING_HV_SINT:
 402                 return kvm_hv_set_sint(irq, kvm, irq_source_id, level,
 403                                        line_status);
 404         default:
 405                 return -EWOULDBLOCK;
 406         }
 407 }
 408
 409 void kvm_arch_irq_routing_update(struct kvm *kvm)
 410 {
 411         kvm_hv_irq_routing_update(kvm);
 412 }