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 #include "x86.h"
  38
  39 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
  40                            struct kvm *kvm, int irq_source_id, int level,
  41                            bool line_status)
  42 {
  43         struct kvm_pic *pic = pic_irqchip(kvm);
  44         return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
  45 }
  46
  47 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
  48                               struct kvm *kvm, int irq_source_id, int level,
  49                               bool line_status)
  50 {
  51         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
  52         return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level,
  53                                 line_status);
  54 }
  55
  56 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
  57                 struct kvm_lapic_irq *irq, struct dest_map *dest_map)
  58 {
  59         int i, r = -1;
  60         struct kvm_vcpu *vcpu, *lowest = NULL;
  61         unsigned long dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
  62         unsigned int dest_vcpus = 0;
  63
  64         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
  65                         kvm_lowest_prio_delivery(irq)) {
  66                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
  67                 irq->delivery_mode = APIC_DM_FIXED;
  68         }
  69
  70         if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
  71                 return r;
  72
  73         memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
  74
  75         kvm_for_each_vcpu(i, vcpu, kvm) {
  76                 if (!kvm_apic_present(vcpu))
  77                         continue;
  78
  79                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
  80                                         irq->dest_id, irq->dest_mode))
  81                         continue;
  82
  83                 if (!kvm_lowest_prio_delivery(irq)) {
  84                         if (r < 0)
  85                                 r = 0;
  86                         r += kvm_apic_set_irq(vcpu, irq, dest_map);
  87                 } else if (kvm_lapic_enabled(vcpu)) {
  88                         if (!kvm_vector_hashing_enabled()) {
  89                                 if (!lowest)
  90                                         lowest = vcpu;
  91                                 else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
  92                                         lowest = vcpu;
  93                         } else {
  94                                 __set_bit(i, dest_vcpu_bitmap);
  95                                 dest_vcpus++;
  96                         }
  97                 }
  98         }
  99
 100         if (dest_vcpus != 0) {
 101                 int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
 102                                         dest_vcpu_bitmap, KVM_MAX_VCPUS);
 103
 104                 lowest = kvm_get_vcpu(kvm, idx);
 105         }
 106
 107         if (lowest)
 108                 r = kvm_apic_set_irq(lowest, irq, dest_map);
 109
 110         return r;
 111 }
 112
 113 void kvm_set_msi_irq(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
 114                      struct kvm_lapic_irq *irq)
 115 {
 116         trace_kvm_msi_set_irq(e->msi.address_lo | (kvm->arch.x2apic_format ?
 117                                              (u64)e->msi.address_hi << 32 : 0),
 118                               e->msi.data);
 119
 120         irq->dest_id = (e->msi.address_lo &
 121                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
 122         if (kvm->arch.x2apic_format)
 123                 irq->dest_id |= MSI_ADDR_EXT_DEST_ID(e->msi.address_hi);
 124         irq->vector = (e->msi.data &
 125                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
 126         irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
 127         irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
 128         irq->delivery_mode = e->msi.data & 0x700;
 129         irq->msi_redir_hint = ((e->msi.address_lo
 130                 & MSI_ADDR_REDIRECTION_LOWPRI) > 0);
 131         irq->level = 1;
 132         irq->shorthand = 0;
 133 }
 134 EXPORT_SYMBOL_GPL(kvm_set_msi_irq);
 135
 136 static inline bool kvm_msi_route_invalid(struct kvm *kvm,
 137                 struct kvm_kernel_irq_routing_entry *e)
 138 {
 139         return kvm->arch.x2apic_format && (e->msi.address_hi & 0xff);
 140 }
 141
 142 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 143                 struct kvm *kvm, int irq_source_id, int level, bool line_status)
 144 {
 145         struct kvm_lapic_irq irq;
 146
 147         if (kvm_msi_route_invalid(kvm, e))
 148                 return -EINVAL;
 149
 150         if (!level)
 151                 return -1;
 152
 153         kvm_set_msi_irq(kvm, e, &irq);
 154
 155         return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL);
 156 }
 157
 158
 159 static int kvm_hv_set_sint(struct kvm_kernel_irq_routing_entry *e,
 160                     struct kvm *kvm, int irq_source_id, int level,
 161                     bool line_status)
 162 {
 163         if (!level)
 164                 return -1;
 165
 166         return kvm_hv_synic_set_irq(kvm, e->hv_sint.vcpu, e->hv_sint.sint);
 167 }
 168
 169 int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
 170                               struct kvm *kvm, int irq_source_id, int level,
 171                               bool line_status)
 172 {
 173         struct kvm_lapic_irq irq;
 174         int r;
 175
 176         switch (e->type) {
 177         case KVM_IRQ_ROUTING_HV_SINT:
 178                 return kvm_hv_set_sint(e, kvm, irq_source_id, level,
 179                                        line_status);
 180
 181         case KVM_IRQ_ROUTING_MSI:
 182                 if (kvm_msi_route_invalid(kvm, e))
 183                         return -EINVAL;
 184
 185                 kvm_set_msi_irq(kvm, e, &irq);
 186
 187                 if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL))
 188                         return r;
 189                 break;
 190
 191         default:
 192                 break;
 193         }
 194
 195         return -EWOULDBLOCK;
 196 }
 197
 198 int kvm_request_irq_source_id(struct kvm *kvm)
 199 {
 200         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
 201         int irq_source_id;
 202
 203         mutex_lock(&kvm->irq_lock);
 204         irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
 205
 206         if (irq_source_id >= BITS_PER_LONG) {
 207                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 208                 irq_source_id = -EFAULT;
 209                 goto unlock;
 210         }
 211
 212         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 213         ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
 214         set_bit(irq_source_id, bitmap);
 215 unlock:
 216         mutex_unlock(&kvm->irq_lock);
 217
 218         return irq_source_id;
 219 }
 220
 221 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 222 {
 223         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 224         ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID);
 225
 226         mutex_lock(&kvm->irq_lock);
 227         if (irq_source_id < 0 ||
 228             irq_source_id >= BITS_PER_LONG) {
 229                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 230                 goto unlock;
 231         }
 232         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
 233         if (!ioapic_in_kernel(kvm))
 234                 goto unlock;
 235
 236         kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
 237         kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id);
 238 unlock:
 239         mutex_unlock(&kvm->irq_lock);
 240 }
 241
 242 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 243                                     struct kvm_irq_mask_notifier *kimn)
 244 {
 245         mutex_lock(&kvm->irq_lock);
 246         kimn->irq = irq;
 247         hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list);
 248         mutex_unlock(&kvm->irq_lock);
 249 }
 250
 251 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
 252                                       struct kvm_irq_mask_notifier *kimn)
 253 {
 254         mutex_lock(&kvm->irq_lock);
 255         hlist_del_rcu(&kimn->link);
 256         mutex_unlock(&kvm->irq_lock);
 257         synchronize_srcu(&kvm->irq_srcu);
 258 }
 259
 260 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
 261                              bool mask)
 262 {
 263         struct kvm_irq_mask_notifier *kimn;
 264         int idx, gsi;
 265
 266         idx = srcu_read_lock(&kvm->irq_srcu);
 267         gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin);
 268         if (gsi != -1)
 269                 hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link)
 270                         if (kimn->irq == gsi)
 271                                 kimn->func(kimn, mask);
 272         srcu_read_unlock(&kvm->irq_srcu, idx);
 273 }
 274
 275 int kvm_set_routing_entry(struct kvm *kvm,
 276                           struct kvm_kernel_irq_routing_entry *e,
 277                           const struct kvm_irq_routing_entry *ue)
 278 {
 279         int r = -EINVAL;
 280         int delta;
 281         unsigned max_pin;
 282
 283         switch (ue->type) {
 284         case KVM_IRQ_ROUTING_IRQCHIP:
 285                 delta = 0;
 286                 switch (ue->u.irqchip.irqchip) {
 287                 case KVM_IRQCHIP_PIC_SLAVE:
 288                         delta = 8;
 289                         /* fall through */
 290                 case KVM_IRQCHIP_PIC_MASTER:
 291                         if (!pic_in_kernel(kvm))
 292                                 goto out;
 293
 294                         e->set = kvm_set_pic_irq;
 295                         max_pin = PIC_NUM_PINS;
 296                         break;
 297                 case KVM_IRQCHIP_IOAPIC:
 298                         if (!ioapic_in_kernel(kvm))
 299                                 goto out;
 300
 301                         max_pin = KVM_IOAPIC_NUM_PINS;
 302                         e->set = kvm_set_ioapic_irq;
 303                         break;
 304                 default:
 305                         goto out;
 306                 }
 307                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
 308                 e->irqchip.pin = ue->u.irqchip.pin + delta;
 309                 if (e->irqchip.pin >= max_pin)
 310                         goto out;
 311                 break;
 312         case KVM_IRQ_ROUTING_MSI:
 313                 e->set = kvm_set_msi;
 314                 e->msi.address_lo = ue->u.msi.address_lo;
 315                 e->msi.address_hi = ue->u.msi.address_hi;
 316                 e->msi.data = ue->u.msi.data;
 317
 318                 if (kvm_msi_route_invalid(kvm, e))
 319                         goto out;
 320                 break;
 321         case KVM_IRQ_ROUTING_HV_SINT:
 322                 e->set = kvm_hv_set_sint;
 323                 e->hv_sint.vcpu = ue->u.hv_sint.vcpu;
 324                 e->hv_sint.sint = ue->u.hv_sint.sint;
 325                 break;
 326         default:
 327                 goto out;
 328         }
 329
 330         r = 0;
 331 out:
 332         return r;
 333 }
 334
 335 bool kvm_intr_is_single_vcpu(struct kvm *kvm, struct kvm_lapic_irq *irq,
 336                              struct kvm_vcpu **dest_vcpu)
 337 {
 338         int i, r = 0;
 339         struct kvm_vcpu *vcpu;
 340
 341         if (kvm_intr_is_single_vcpu_fast(kvm, irq, dest_vcpu))
 342                 return true;
 343
 344         kvm_for_each_vcpu(i, vcpu, kvm) {
 345                 if (!kvm_apic_present(vcpu))
 346                         continue;
 347
 348                 if (!kvm_apic_match_dest(vcpu, NULL, irq->shorthand,
 349                                         irq->dest_id, irq->dest_mode))
 350                         continue;
 351
 352                 if (++r == 2)
 353                         return false;
 354
 355                 *dest_vcpu = vcpu;
 356         }
 357
 358         return r == 1;
 359 }
 360 EXPORT_SYMBOL_GPL(kvm_intr_is_single_vcpu);
 361
 362 #define IOAPIC_ROUTING_ENTRY(irq) \
 363         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 364           .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } }
 365 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 366
 367 #define PIC_ROUTING_ENTRY(irq) \
 368         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 369           .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } }
 370 #define ROUTING_ENTRY2(irq) \
 371         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
 372
 373 static const struct kvm_irq_routing_entry default_routing[] = {
 374         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
 375         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
 376         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
 377         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
 378         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
 379         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
 380         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
 381         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
 382         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
 383         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
 384         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
 385         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
 386 };
 387
 388 int kvm_setup_default_irq_routing(struct kvm *kvm)
 389 {
 390         return kvm_set_irq_routing(kvm, default_routing,
 391                                    ARRAY_SIZE(default_routing), 0);
 392 }
 393
 394 static const struct kvm_irq_routing_entry empty_routing[] = {};
 395
 396 int kvm_setup_empty_irq_routing(struct kvm *kvm)
 397 {
 398         return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
 399 }
 400
 401 void kvm_arch_post_irq_routing_update(struct kvm *kvm)
 402 {
 403         if (!irqchip_split(kvm))
 404                 return;
 405         kvm_make_scan_ioapic_request(kvm);
 406 }
 407
 408 void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
 409                             ulong *ioapic_handled_vectors)
 410 {
 411         struct kvm *kvm = vcpu->kvm;
 412         struct kvm_kernel_irq_routing_entry *entry;
 413         struct kvm_irq_routing_table *table;
 414         u32 i, nr_ioapic_pins;
 415         int idx;
 416
 417         idx = srcu_read_lock(&kvm->irq_srcu);
 418         table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
 419         nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
 420                                kvm->arch.nr_reserved_ioapic_pins);
 421         for (i = 0; i < nr_ioapic_pins; ++i) {
 422                 hlist_for_each_entry(entry, &table->map[i], link) {
 423                         struct kvm_lapic_irq irq;
 424
 425                         if (entry->type != KVM_IRQ_ROUTING_MSI)
 426                                 continue;
 427
 428                         kvm_set_msi_irq(vcpu->kvm, entry, &irq);
 429
 430                         if (irq.level && kvm_apic_match_dest(vcpu, NULL, 0,
 431                                                 irq.dest_id, irq.dest_mode))
 432                                 __set_bit(irq.vector, ioapic_handled_vectors);
 433                 }
 434         }
 435         srcu_read_unlock(&kvm->irq_srcu, idx);
 436 }
 437
 438 void kvm_arch_irq_routing_update(struct kvm *kvm)
 439 {
 440         kvm_hv_irq_routing_update(kvm);
 441 }