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