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 #ifdef CONFIG_X86
  25 #include <asm/msidef.h>
  26 #endif
  27
  28 #include "irq.h"
  29
  30 #include "ioapic.h"
  31
  32 static void kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
  33                             struct kvm *kvm, int level)
  34 {
  35 #ifdef CONFIG_X86
  36         kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
  37 #endif
  38 }
  39
  40 static void kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
  41                                struct kvm *kvm, int level)
  42 {
  43         kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
  44 }
  45
  46 static void kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
  47                         struct kvm *kvm, int level)
  48 {
  49         int vcpu_id;
  50         struct kvm_vcpu *vcpu;
  51         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
  52         int dest_id = (e->msi.address_lo & MSI_ADDR_DEST_ID_MASK)
  53                         >> MSI_ADDR_DEST_ID_SHIFT;
  54         int vector = (e->msi.data & MSI_DATA_VECTOR_MASK)
  55                         >> MSI_DATA_VECTOR_SHIFT;
  56         int dest_mode = test_bit(MSI_ADDR_DEST_MODE_SHIFT,
  57                                 (unsigned long *)&e->msi.address_lo);
  58         int trig_mode = test_bit(MSI_DATA_TRIGGER_SHIFT,
  59                                 (unsigned long *)&e->msi.data);
  60         int delivery_mode = test_bit(MSI_DATA_DELIVERY_MODE_SHIFT,
  61                                 (unsigned long *)&e->msi.data);
  62         u32 deliver_bitmask;
  63
  64         BUG_ON(!ioapic);
  65
  66         deliver_bitmask = kvm_ioapic_get_delivery_bitmask(ioapic,
  67                                 dest_id, dest_mode);
  68         /* IOAPIC delivery mode value is the same as MSI here */
  69         switch (delivery_mode) {
  70         case IOAPIC_LOWEST_PRIORITY:
  71                 vcpu = kvm_get_lowest_prio_vcpu(ioapic->kvm, vector,
  72                                 deliver_bitmask);
  73                 if (vcpu != NULL)
  74                         kvm_apic_set_irq(vcpu, vector, trig_mode);
  75                 else
  76                         printk(KERN_INFO "kvm: null lowest priority vcpu!\n");
  77                 break;
  78         case IOAPIC_FIXED:
  79                 for (vcpu_id = 0; deliver_bitmask != 0; vcpu_id++) {
  80                         if (!(deliver_bitmask & (1 << vcpu_id)))
  81                                 continue;
  82                         deliver_bitmask &= ~(1 << vcpu_id);
  83                         vcpu = ioapic->kvm->vcpus[vcpu_id];
  84                         if (vcpu)
  85                                 kvm_apic_set_irq(vcpu, vector, trig_mode);
  86                 }
  87                 break;
  88         default:
  89                 break;
  90         }
  91 }
  92
  93 /* This should be called with the kvm->lock mutex held */
  94 void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
  95 {
  96         struct kvm_kernel_irq_routing_entry *e;
  97         unsigned long *irq_state, sig_level;
  98
  99         if (irq < KVM_IOAPIC_NUM_PINS) {
 100                 irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
 101
 102                 /* Logical OR for level trig interrupt */
 103                 if (level)
 104                         set_bit(irq_source_id, irq_state);
 105                 else
 106                         clear_bit(irq_source_id, irq_state);
 107                 sig_level = !!(*irq_state);
 108         } else /* Deal with MSI/MSI-X */
 109                 sig_level = 1;
 110
 111         /* Not possible to detect if the guest uses the PIC or the
 112          * IOAPIC.  So set the bit in both. The guest will ignore
 113          * writes to the unused one.
 114          */
 115         list_for_each_entry(e, &kvm->irq_routing, link)
 116                 if (e->gsi == irq)
 117                         e->set(e, kvm, sig_level);
 118 }
 119
 120 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
 121 {
 122         struct kvm_kernel_irq_routing_entry *e;
 123         struct kvm_irq_ack_notifier *kian;
 124         struct hlist_node *n;
 125         unsigned gsi = pin;
 126
 127         list_for_each_entry(e, &kvm->irq_routing, link)
 128                 if (e->irqchip.irqchip == irqchip &&
 129                     e->irqchip.pin == pin) {
 130                         gsi = e->gsi;
 131                         break;
 132                 }
 133
 134         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
 135                 if (kian->gsi == gsi)
 136                         kian->irq_acked(kian);
 137 }
 138
 139 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 140                                    struct kvm_irq_ack_notifier *kian)
 141 {
 142         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
 143 }
 144
 145 void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian)
 146 {
 147         hlist_del_init(&kian->link);
 148 }
 149
 150 /* The caller must hold kvm->lock mutex */
 151 int kvm_request_irq_source_id(struct kvm *kvm)
 152 {
 153         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
 154         int irq_source_id = find_first_zero_bit(bitmap,
 155                                 sizeof(kvm->arch.irq_sources_bitmap));
 156
 157         if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 158                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
 159                 return -EFAULT;
 160         }
 161
 162         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 163         set_bit(irq_source_id, bitmap);
 164
 165         return irq_source_id;
 166 }
 167
 168 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
 169 {
 170         int i;
 171
 172         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
 173
 174         if (irq_source_id < 0 ||
 175             irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
 176                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
 177                 return;
 178         }
 179         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
 180                 clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
 181         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
 182 }
 183
 184 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
 185                                     struct kvm_irq_mask_notifier *kimn)
 186 {
 187         kimn->irq = irq;
 188         hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
 189 }
 190
 191 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
 192                                       struct kvm_irq_mask_notifier *kimn)
 193 {
 194         hlist_del(&kimn->link);
 195 }
 196
 197 void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
 198 {
 199         struct kvm_irq_mask_notifier *kimn;
 200         struct hlist_node *n;
 201
 202         hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
 203                 if (kimn->irq == irq)
 204                         kimn->func(kimn, mask);
 205 }
 206
 207 static void __kvm_free_irq_routing(struct list_head *irq_routing)
 208 {
 209         struct kvm_kernel_irq_routing_entry *e, *n;
 210
 211         list_for_each_entry_safe(e, n, irq_routing, link)
 212                 kfree(e);
 213 }
 214
 215 void kvm_free_irq_routing(struct kvm *kvm)
 216 {
 217         __kvm_free_irq_routing(&kvm->irq_routing);
 218 }
 219
 220 int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
 221                         const struct kvm_irq_routing_entry *ue)
 222 {
 223         int r = -EINVAL;
 224         int delta;
 225
 226         e->gsi = ue->gsi;
 227         switch (ue->type) {
 228         case KVM_IRQ_ROUTING_IRQCHIP:
 229                 delta = 0;
 230                 switch (ue->u.irqchip.irqchip) {
 231                 case KVM_IRQCHIP_PIC_MASTER:
 232                         e->set = kvm_set_pic_irq;
 233                         break;
 234                 case KVM_IRQCHIP_PIC_SLAVE:
 235                                 e->set = kvm_set_pic_irq;
 236                         delta = 8;
 237                         break;
 238                 case KVM_IRQCHIP_IOAPIC:
 239                                 e->set = kvm_set_ioapic_irq;
 240                         break;
 241                 default:
 242                         goto out;
 243                 }
 244                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
 245                 e->irqchip.pin = ue->u.irqchip.pin + delta;
 246                 break;
 247         case KVM_IRQ_ROUTING_MSI:
 248                 e->set = kvm_set_msi;
 249                 e->msi.address_lo = ue->u.msi.address_lo;
 250                 e->msi.address_hi = ue->u.msi.address_hi;
 251                 e->msi.data = ue->u.msi.data;
 252                 break;
 253         default:
 254                 goto out;
 255         }
 256         r = 0;
 257 out:
 258         return r;
 259 }
 260
 261
 262 int kvm_set_irq_routing(struct kvm *kvm,
 263                         const struct kvm_irq_routing_entry *ue,
 264                         unsigned nr,
 265                         unsigned flags)
 266 {
 267         struct list_head irq_list = LIST_HEAD_INIT(irq_list);
 268         struct list_head tmp = LIST_HEAD_INIT(tmp);
 269         struct kvm_kernel_irq_routing_entry *e = NULL;
 270         unsigned i;
 271         int r;
 272
 273         for (i = 0; i < nr; ++i) {
 274                 r = -EINVAL;
 275                 if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
 276                         goto out;
 277                 if (ue->flags)
 278                         goto out;
 279                 r = -ENOMEM;
 280                 e = kzalloc(sizeof(*e), GFP_KERNEL);
 281                 if (!e)
 282                         goto out;
 283                 r = setup_routing_entry(e, ue);
 284                 if (r)
 285                         goto out;
 286                 ++ue;
 287                 list_add(&e->link, &irq_list);
 288                 e = NULL;
 289         }
 290
 291         mutex_lock(&kvm->lock);
 292         list_splice(&kvm->irq_routing, &tmp);
 293         INIT_LIST_HEAD(&kvm->irq_routing);
 294         list_splice(&irq_list, &kvm->irq_routing);
 295         INIT_LIST_HEAD(&irq_list);
 296         list_splice(&tmp, &irq_list);
 297         mutex_unlock(&kvm->lock);
 298
 299         r = 0;
 300
 301 out:
 302         kfree(e);
 303         __kvm_free_irq_routing(&irq_list);
 304         return r;
 305 }
 306
 307 #define IOAPIC_ROUTING_ENTRY(irq) \
 308         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 309           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
 310 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
 311
 312 #ifdef CONFIG_X86
 313 #  define PIC_ROUTING_ENTRY(irq) \
 314         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
 315           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
 316 #  define ROUTING_ENTRY2(irq) \
 317         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
 318 #else
 319 #  define ROUTING_ENTRY2(irq) \
 320         IOAPIC_ROUTING_ENTRY(irq)
 321 #endif
 322
 323 static const struct kvm_irq_routing_entry default_routing[] = {
 324         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
 325         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
 326         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
 327         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
 328         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
 329         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
 330         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
 331         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
 332         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
 333         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
 334         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
 335         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
 336 #ifdef CONFIG_IA64
 337         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
 338         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
 339         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
 340         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
 341         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
 342         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
 343         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
 344         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
 345         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
 346         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
 347         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
 348         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
 349 #endif
 350 };
 351
 352 int kvm_setup_default_irq_routing(struct kvm *kvm)
 353 {
 354         return kvm_set_irq_routing(kvm, default_routing,
 355                                    ARRAY_SIZE(default_routing), 0);
 356 }