SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 #include <trace/events/kvm.h>
  24
  25 #include <asm/msidef.h>
  26 #ifdef CONFIG_IA64
  27 #include <asm/iosapic.h>
  28 #endif
  29
  30 #include "irq.h"
  31
  32 #include "ioapic.h"
  33
  34 static inline int kvm_irq_line_state(unsigned long *irq_state,
  35                                      int irq_source_id, int level)
  36 {
  37         /* Logical OR for level trig interrupt */
  38         if (level)
  39                 set_bit(irq_source_id, irq_state);
  40         else
  41                 clear_bit(irq_source_id, irq_state);
  42
  43         return !!(*irq_state);
  44 }
  45
  46 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
  47                            struct kvm *kvm, int irq_source_id, int level)
  48 {
  49 #ifdef CONFIG_X86
  50         struct kvm_pic *pic = pic_irqchip(kvm);
  51         level = kvm_irq_line_state(&pic->irq_states[e->irqchip.pin],
  52                                    irq_source_id, level);
  53         return kvm_pic_set_irq(pic, e->irqchip.pin, level);
  54 #else
  55         return -1;
  56 #endif
  57 }
  58
  59 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
  60                               struct kvm *kvm, int irq_source_id, int level)
  61 {
  62         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
  63         level = kvm_irq_line_state(&ioapic->irq_states[e->irqchip.pin],
  64                                    irq_source_id, level);
  65
  66         return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, level);
  67 }
  68
  69 inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
  70 {
  71 #ifdef CONFIG_IA64
  72         return irq->delivery_mode ==
  73                 (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
  74 #else
  75         return irq->delivery_mode == APIC_DM_LOWEST;
  76 #endif
  77 }
  78
  79 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
  80                 struct kvm_lapic_irq *irq)
  81 {
  82         int i, r = -1;
  83         struct kvm_vcpu *vcpu, *lowest = NULL;
  84
  85         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
  86
  87         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
  88                         kvm_is_dm_lowest_prio(irq))
  89                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
  90
  91         kvm_for_each_vcpu(i, vcpu, kvm) {
  92                 if (!kvm_apic_present(vcpu))
  93                         continue;
  94
  95                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
  96                                         irq->dest_id, irq->dest_mode))
  97                         continue;
  98
  99                 if (!kvm_is_dm_lowest_prio(irq)) {
 100                         if (r < 0)
 101                                 r = 0;
 102                         r += kvm_apic_set_irq(vcpu, irq);
 103                 } else {
 104                         if (!lowest)
 105                                 lowest = vcpu;
 106                         else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
 107                                 lowest = vcpu;
 108                 }
 109         }
 110
 111         if (lowest)
 112                 r = kvm_apic_set_irq(lowest, irq);
 113
 114         return r;
 115 }
 116
 117 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 118                        struct kvm *kvm, int irq_source_id, int level)
 119 {
 120         struct kvm_lapic_irq irq;
 121
 122         if (!level)
 123                 return -1;
 124
 125         trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
 126
 127         irq.dest_id = (e->msi.address_lo &
 128                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
 129         irq.vector = (e->msi.data &
 130                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
 131         irq.dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
 132         irq.trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
 133         irq.delivery_mode = e->msi.data & 0x700;
 134         irq.level = 1;
 135         irq.shorthand = 0;
 136
 137         /* TODO Deal with RH bit of MSI message address */
 138         return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
 139 }
 140
 141 /* This should be called with the kvm->irq_lock mutex held
 142  * Return value:
 143  *  < 0   Interrupt was ignored (masked or not delivered for other reasons)
 144  *  = 0   Interrupt was coalesced (previous irq is still pending)
 145  *  > 0   Number of CPUs interrupt was delivered to
 146  */
 147 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
 148 {
 149         struct kvm_kernel_irq_routing_entry *e;
 150         int ret = -1;
 151
 152         trace_kvm_set_irq(irq, level, irq_source_id);
 153
 154         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
 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, irq_source_id, 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         trace_kvm_ack_irq(irqchip, pin);
 179
 180         list_for_each_entry(e, &kvm->irq_routing, link)
 181                 if (e->type == KVM_IRQ_ROUTING_IRQCHIP &&
 182                     e->irqchip.irqchip == irqchip &&
 183                     e->irqchip.pin == pin) {
 184                         gsi = e->gsi;
 185                         break;
 186                 }
 187
 188         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
 189                 if (kian->gsi == gsi)
 190                         kian->irq_acked(kian);
 191 }
 192
 193 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 194                                    struct kvm_irq_ack_notifier *kian)
 195 {
 196         mutex_lock(&kvm->irq_lock);
 197         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
 198         mutex_unlock(&kvm->irq_lock);
 199 }
 200
 201 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
 202                                     struct kvm_irq_ack_notifier *kian)
 203 {
 204         mutex_lock(&kvm->irq_lock);
 205         hlist_del_init(&kian->link);
 206         mutex_unlock(&kvm->irq_lock);
 207 }
 208
 209 int kvm_request_irq_source_id(struct kvm *kvm)
 210 {
 211         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
 212         int irq_source_id;
 213
 214         mutex_lock(&kvm->irq_lock);
 215         irq_source_id = find_first_zero_bit(bitmap,
 216                                 sizeof(kvm->arch.irq_sources_bitmap));
 217
 218         if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 219                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 220                 return -EFAULT;
 221         }
 222
 223         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 224         set_bit(irq_source_id, bitmap);
 225         mutex_unlock(&kvm->irq_lock);
 226
 227         return irq_source_id;
 228 }
 229
 230 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 231 {
 232         int i;
 233
 234         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 235
 236         mutex_lock(&kvm->irq_lock);
 237         if (irq_source_id < 0 ||
 238             irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 239                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 240                 return;
 241         }
 242         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++) {
 243                 clear_bit(irq_source_id, &kvm->arch.vioapic->irq_states[i]);
 244                 if (i >= 16)
 245                         continue;
 246 #ifdef CONFIG_X86
 247                 clear_bit(irq_source_id, &pic_irqchip(kvm)->irq_states[i]);
 248 #endif
 249         }
 250         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
 251         mutex_unlock(&kvm->irq_lock);
 252 }
 253
 254 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 255                                     struct kvm_irq_mask_notifier *kimn)
 256 {
 257         mutex_lock(&kvm->irq_lock);
 258         kimn->irq = irq;
 259         hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
 260         mutex_unlock(&kvm->irq_lock);
 261 }
 262
 263 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
 264                                       struct kvm_irq_mask_notifier *kimn)
 265 {
 266         mutex_lock(&kvm->irq_lock);
 267         hlist_del(&kimn->link);
 268         mutex_unlock(&kvm->irq_lock);
 269 }
 270
 271 void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
 272 {
 273         struct kvm_irq_mask_notifier *kimn;
 274         struct hlist_node *n;
 275
 276         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
 277
 278         hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
 279                 if (kimn->irq == irq)
 280                         kimn->func(kimn, mask);
 281 }
 282
 283 static void __kvm_free_irq_routing(struct list_head *irq_routing)
 284 {
 285         struct kvm_kernel_irq_routing_entry *e, *n;
 286
 287         list_for_each_entry_safe(e, n, irq_routing, link)
 288                 kfree(e);
 289 }
 290
 291 void kvm_free_irq_routing(struct kvm *kvm)
 292 {
 293         mutex_lock(&kvm->irq_lock);
 294         __kvm_free_irq_routing(&kvm->irq_routing);
 295         mutex_unlock(&kvm->irq_lock);
 296 }
 297
 298 static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
 299                                const struct kvm_irq_routing_entry *ue)
 300 {
 301         int r = -EINVAL;
 302         int delta;
 303
 304         e->gsi = ue->gsi;
 305         e->type = ue->type;
 306         switch (ue->type) {
 307         case KVM_IRQ_ROUTING_IRQCHIP:
 308                 delta = 0;
 309                 switch (ue->u.irqchip.irqchip) {
 310                 case KVM_IRQCHIP_PIC_MASTER:
 311                         e->set = kvm_set_pic_irq;
 312                         break;
 313                 case KVM_IRQCHIP_PIC_SLAVE:
 314                         e->set = kvm_set_pic_irq;
 315                         delta = 8;
 316                         break;
 317                 case KVM_IRQCHIP_IOAPIC:
 318                         e->set = kvm_set_ioapic_irq;
 319                         break;
 320                 default:
 321                         goto out;
 322                 }
 323                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
 324                 e->irqchip.pin = ue->u.irqchip.pin + delta;
 325                 break;
 326         case KVM_IRQ_ROUTING_MSI:
 327                 e->set = kvm_set_msi;
 328                 e->msi.address_lo = ue->u.msi.address_lo;
 329                 e->msi.address_hi = ue->u.msi.address_hi;
 330                 e->msi.data = ue->u.msi.data;
 331                 break;
 332         default:
 333                 goto out;
 334         }
 335         r = 0;
 336 out:
 337         return r;
 338 }
 339
 340
 341 int kvm_set_irq_routing(struct kvm *kvm,
 342                         const struct kvm_irq_routing_entry *ue,
 343                         unsigned nr,
 344                         unsigned flags)
 345 {
 346         struct list_head irq_list = LIST_HEAD_INIT(irq_list);
 347         struct list_head tmp = LIST_HEAD_INIT(tmp);
 348         struct kvm_kernel_irq_routing_entry *e = NULL;
 349         unsigned i;
 350         int r;
 351
 352         for (i = 0; i < nr; ++i) {
 353                 r = -EINVAL;
 354                 if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
 355                         goto out;
 356                 if (ue->flags)
 357                         goto out;
 358                 r = -ENOMEM;
 359                 e = kzalloc(sizeof(*e), GFP_KERNEL);
 360                 if (!e)
 361                         goto out;
 362                 r = setup_routing_entry(e, ue);
 363                 if (r)
 364                         goto out;
 365                 ++ue;
 366                 list_add(&e->link, &irq_list);
 367                 e = NULL;
 368         }
 369
 370         mutex_lock(&kvm->irq_lock);
 371         list_splice(&kvm->irq_routing, &tmp);
 372         INIT_LIST_HEAD(&kvm->irq_routing);
 373         list_splice(&irq_list, &kvm->irq_routing);
 374         INIT_LIST_HEAD(&irq_list);
 375         list_splice(&tmp, &irq_list);
 376         mutex_unlock(&kvm->irq_lock);
 377
 378         r = 0;
 379
 380 out:
 381         kfree(e);
 382         __kvm_free_irq_routing(&irq_list);
 383         return r;
 384 }
 385
 386 #define IOAPIC_ROUTING_ENTRY(irq) \
 387         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 388           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
 389 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 390
 391 #ifdef CONFIG_X86
 392 #  define PIC_ROUTING_ENTRY(irq) \
 393         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 394           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
 395 #  define ROUTING_ENTRY2(irq) \
 396         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
 397 #else
 398 #  define ROUTING_ENTRY2(irq) \
 399         IOAPIC_ROUTING_ENTRY(irq)
 400 #endif
 401
 402 static const struct kvm_irq_routing_entry default_routing[] = {
 403         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
 404         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
 405         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
 406         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
 407         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
 408         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
 409         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
 410         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
 411         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
 412         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
 413         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
 414         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
 415 #ifdef CONFIG_IA64
 416         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
 417         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
 418         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
 419         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
 420         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
 421         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
 422         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
 423         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
 424         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
 425         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
 426         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
 427         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
 428 #endif
 429 };
 430
 431 int kvm_setup_default_irq_routing(struct kvm *kvm)
 432 {
 433         return kvm_set_irq_routing(kvm, default_routing,
 434                                    ARRAY_SIZE(default_routing), 0);
 435 }