virt/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  */
  21
  22 #include <linux/kvm_host.h>
  23
  24 #include <asm/msidef.h>
  25
  26 #include "irq.h"
  27
  28 #include "ioapic.h"
  29
  30 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
  31                            struct kvm *kvm, int level)
  32 {
  33 #ifdef CONFIG_X86
  34         return kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
  35 #else
  36         return -1;
  37 #endif
  38 }
  39
  40 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
  41                               struct kvm *kvm, int level)
  42 {
  43         return kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
  44 }
  45
  46 void kvm_get_intr_delivery_bitmask(struct kvm *kvm,
  47                                    union kvm_ioapic_redirect_entry *entry,
  48                                    unsigned long *deliver_bitmask)
  49 {
  50         int i;
  51         struct kvm_vcpu *vcpu;
  52
  53         bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
  54
  55         if (entry->fields.dest_mode == 0) {     /* Physical mode. */
  56                 if (entry->fields.dest_id == 0xFF) {    /* Broadcast. */
  57                         for (i = 0; i < KVM_MAX_VCPUS; ++i)
  58                                 if (kvm->vcpus[i] && kvm->vcpus[i]->arch.apic)
  59                                         __set_bit(i, deliver_bitmask);
  60                         /* Lowest priority shouldn't combine with broadcast */
  61                         if (entry->fields.delivery_mode ==
  62                             IOAPIC_LOWEST_PRIORITY && printk_ratelimit())
  63                                 printk(KERN_INFO "kvm: apic: phys broadcast "
  64                                                   "and lowest prio\n");
  65                         return;
  66                 }
  67                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
  68                         vcpu = kvm->vcpus[i];
  69                         if (!vcpu)
  70                                 continue;
  71                         if (kvm_apic_match_physical_addr(vcpu->arch.apic,
  72                                         entry->fields.dest_id)) {
  73                                 if (vcpu->arch.apic)
  74                                         __set_bit(i, deliver_bitmask);
  75                                 break;
  76                         }
  77                 }
  78         } else if (entry->fields.dest_id != 0) /* Logical mode, MDA non-zero. */
  79                 for (i = 0; i < KVM_MAX_VCPUS; ++i) {
  80                         vcpu = kvm->vcpus[i];
  81                         if (!vcpu)
  82                                 continue;
  83                         if (vcpu->arch.apic &&
  84                             kvm_apic_match_logical_addr(vcpu->arch.apic,
  85                                         entry->fields.dest_id))
  86                                 __set_bit(i, deliver_bitmask);
  87                 }
  88
  89         switch (entry->fields.delivery_mode) {
  90         case IOAPIC_LOWEST_PRIORITY:
  91                 /* Select one in deliver_bitmask */
  92                 vcpu = kvm_get_lowest_prio_vcpu(kvm,
  93                                 entry->fields.vector, deliver_bitmask);
  94                 bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
  95                 if (!vcpu)
  96                         return;
  97                 __set_bit(vcpu->vcpu_id, deliver_bitmask);
  98                 break;
  99         case IOAPIC_FIXED:
 100         case IOAPIC_NMI:
 101                 break;
 102         default:
 103                 if (printk_ratelimit())
 104                         printk(KERN_INFO "kvm: unsupported delivery mode %d\n",
 105                                 entry->fields.delivery_mode);
 106                 bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
 107         }
 108 }
 109
 110 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 111                        struct kvm *kvm, int level)
 112 {
 113         union kvm_ioapic_redirect_entry entry;
 114
 115         entry.bits = 0;
 116         entry.fields.dest_id = (e->msi.address_lo &
 117                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
 118         entry.fields.vector = (e->msi.data &
 119                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
 120         entry.fields.dest_mode = test_bit(MSI_ADDR_DEST_MODE_SHIFT,
 121                         (unsigned long *)&e->msi.address_lo);
 122         entry.fields.trig_mode = test_bit(MSI_DATA_TRIGGER_SHIFT,
 123                         (unsigned long *)&e->msi.data);
 124         entry.fields.delivery_mode = test_bit(
 125                         MSI_DATA_DELIVERY_MODE_SHIFT,
 126                         (unsigned long *)&e->msi.data);
 127
 128         /* TODO Deal with RH bit of MSI message address */
 129         return ioapic_deliver_entry(kvm, &entry);
 130 }
 131
 132 /* This should be called with the kvm->lock mutex held
 133  * Return value:
 134  *  < 0   Interrupt was ignored (masked or not delivered for other reasons)
 135  *  = 0   Interrupt was coalesced (previous irq is still pending)
 136  *  > 0   Number of CPUs interrupt was delivered to
 137  */
 138 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
 139 {
 140         struct kvm_kernel_irq_routing_entry *e;
 141         unsigned long *irq_state, sig_level;
 142         int ret = -1;
 143
 144         if (irq < KVM_IOAPIC_NUM_PINS) {
 145                 irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
 146
 147                 /* Logical OR for level trig interrupt */
 148                 if (level)
 149                         set_bit(irq_source_id, irq_state);
 150                 else
 151                         clear_bit(irq_source_id, irq_state);
 152                 sig_level = !!(*irq_state);
 153         } else /* Deal with MSI/MSI-X */
 154                 sig_level = 1;
 155
 156         /* Not possible to detect if the guest uses the PIC or the
 157          * IOAPIC.  So set the bit in both. The guest will ignore
 158          * writes to the unused one.
 159          */
 160         list_for_each_entry(e, &kvm->irq_routing, link)
 161                 if (e->gsi == irq) {
 162                         int r = e->set(e, kvm, sig_level);
 163                         if (r < 0)
 164                                 continue;
 165
 166                         ret = r + ((ret < 0) ? 0 : ret);
 167                 }
 168         return ret;
 169 }
 170
 171 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
 172 {
 173         struct kvm_kernel_irq_routing_entry *e;
 174         struct kvm_irq_ack_notifier *kian;
 175         struct hlist_node *n;
 176         unsigned gsi = pin;
 177
 178         list_for_each_entry(e, &kvm->irq_routing, link)
 179                 if (e->irqchip.irqchip == irqchip &&
 180                     e->irqchip.pin == pin) {
 181                         gsi = e->gsi;
 182                         break;
 183                 }
 184
 185         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
 186                 if (kian->gsi == gsi)
 187                         kian->irq_acked(kian);
 188 }
 189
 190 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 191                                    struct kvm_irq_ack_notifier *kian)
 192 {
 193         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
 194 }
 195
 196 void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian)
 197 {
 198         hlist_del_init(&kian->link);
 199 }
 200
 201 /* The caller must hold kvm->lock mutex */
 202 int kvm_request_irq_source_id(struct kvm *kvm)
 203 {
 204         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
 205         int irq_source_id = find_first_zero_bit(bitmap,
 206                                 sizeof(kvm->arch.irq_sources_bitmap));
 207
 208         if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 209                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 210                 return -EFAULT;
 211         }
 212
 213         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 214         set_bit(irq_source_id, bitmap);
 215
 216         return irq_source_id;
 217 }
 218
 219 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 220 {
 221         int i;
 222
 223         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 224
 225         if (irq_source_id < 0 ||
 226             irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 227                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 228                 return;
 229         }
 230         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
 231                 clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
 232         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
 233 }
 234
 235 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 236                                     struct kvm_irq_mask_notifier *kimn)
 237 {
 238         kimn->irq = irq;
 239         hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
 240 }
 241
 242 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
 243                                       struct kvm_irq_mask_notifier *kimn)
 244 {
 245         hlist_del(&kimn->link);
 246 }
 247
 248 void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
 249 {
 250         struct kvm_irq_mask_notifier *kimn;
 251         struct hlist_node *n;
 252
 253         hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
 254                 if (kimn->irq == irq)
 255                         kimn->func(kimn, mask);
 256 }
 257
 258 static void __kvm_free_irq_routing(struct list_head *irq_routing)
 259 {
 260         struct kvm_kernel_irq_routing_entry *e, *n;
 261
 262         list_for_each_entry_safe(e, n, irq_routing, link)
 263                 kfree(e);
 264 }
 265
 266 void kvm_free_irq_routing(struct kvm *kvm)
 267 {
 268         __kvm_free_irq_routing(&kvm->irq_routing);
 269 }
 270
 271 static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
 272                                const struct kvm_irq_routing_entry *ue)
 273 {
 274         int r = -EINVAL;
 275         int delta;
 276
 277         e->gsi = ue->gsi;
 278         switch (ue->type) {
 279         case KVM_IRQ_ROUTING_IRQCHIP:
 280                 delta = 0;
 281                 switch (ue->u.irqchip.irqchip) {
 282                 case KVM_IRQCHIP_PIC_MASTER:
 283                         e->set = kvm_set_pic_irq;
 284                         break;
 285                 case KVM_IRQCHIP_PIC_SLAVE:
 286                         e->set = kvm_set_pic_irq;
 287                         delta = 8;
 288                         break;
 289                 case KVM_IRQCHIP_IOAPIC:
 290                                 e->set = kvm_set_ioapic_irq;
 291                         break;
 292                 default:
 293                         goto out;
 294                 }
 295                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
 296                 e->irqchip.pin = ue->u.irqchip.pin + delta;
 297                 break;
 298         case KVM_IRQ_ROUTING_MSI:
 299                 e->set = kvm_set_msi;
 300                 e->msi.address_lo = ue->u.msi.address_lo;
 301                 e->msi.address_hi = ue->u.msi.address_hi;
 302                 e->msi.data = ue->u.msi.data;
 303                 break;
 304         default:
 305                 goto out;
 306         }
 307         r = 0;
 308 out:
 309         return r;
 310 }
 311
 312
 313 int kvm_set_irq_routing(struct kvm *kvm,
 314                         const struct kvm_irq_routing_entry *ue,
 315                         unsigned nr,
 316                         unsigned flags)
 317 {
 318         struct list_head irq_list = LIST_HEAD_INIT(irq_list);
 319         struct list_head tmp = LIST_HEAD_INIT(tmp);
 320         struct kvm_kernel_irq_routing_entry *e = NULL;
 321         unsigned i;
 322         int r;
 323
 324         for (i = 0; i < nr; ++i) {
 325                 r = -EINVAL;
 326                 if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
 327                         goto out;
 328                 if (ue->flags)
 329                         goto out;
 330                 r = -ENOMEM;
 331                 e = kzalloc(sizeof(*e), GFP_KERNEL);
 332                 if (!e)
 333                         goto out;
 334                 r = setup_routing_entry(e, ue);
 335                 if (r)
 336                         goto out;
 337                 ++ue;
 338                 list_add(&e->link, &irq_list);
 339                 e = NULL;
 340         }
 341
 342         mutex_lock(&kvm->lock);
 343         list_splice(&kvm->irq_routing, &tmp);
 344         INIT_LIST_HEAD(&kvm->irq_routing);
 345         list_splice(&irq_list, &kvm->irq_routing);
 346         INIT_LIST_HEAD(&irq_list);
 347         list_splice(&tmp, &irq_list);
 348         mutex_unlock(&kvm->lock);
 349
 350         r = 0;
 351
 352 out:
 353         kfree(e);
 354         __kvm_free_irq_routing(&irq_list);
 355         return r;
 356 }
 357
 358 #define IOAPIC_ROUTING_ENTRY(irq) \
 359         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 360           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
 361 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 362
 363 #ifdef CONFIG_X86
 364 #  define PIC_ROUTING_ENTRY(irq) \
 365         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 366           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
 367 #  define ROUTING_ENTRY2(irq) \
 368         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
 369 #else
 370 #  define ROUTING_ENTRY2(irq) \
 371         IOAPIC_ROUTING_ENTRY(irq)
 372 #endif
 373
 374 static const struct kvm_irq_routing_entry default_routing[] = {
 375         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
 376         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
 377         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
 378         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
 379         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
 380         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
 381         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
 382         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
 383         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
 384         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
 385         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
 386         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
 387 #ifdef CONFIG_IA64
 388         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
 389         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
 390         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
 391         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
 392         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
 393         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
 394         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
 395         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
 396         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
 397         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
 398         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
 399         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
 400 #endif
 401 };
 402
 403 int kvm_setup_default_irq_routing(struct kvm *kvm)
 404 {
 405         return kvm_set_irq_routing(kvm, default_routing,
 406                                    ARRAY_SIZE(default_routing), 0);
 407 }