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-rw-r--r--virt/kvm/irq_comm.c474
1 files changed, 474 insertions, 0 deletions
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
new file mode 100644
index 00000000..9f614b4e
--- /dev/null
+++ b/virt/kvm/irq_comm.c
@@ -0,0 +1,474 @@
+/*
+ * irq_comm.c: Common API for in kernel interrupt controller
+ * Copyright (c) 2007, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ * Authors:
+ * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
+ *
+ * Copyright 2010 Red Hat, Inc. and/or its affiliates.
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/slab.h>
+#include <trace/events/kvm.h>
+
+#include <asm/msidef.h>
+#ifdef CONFIG_IA64
+#include <asm/iosapic.h>
+#endif
+
+#include "irq.h"
+
+#include "ioapic.h"
+
+static inline int kvm_irq_line_state(unsigned long *irq_state,
+ int irq_source_id, int level)
+{
+ /* Logical OR for level trig interrupt */
+ if (level)
+ set_bit(irq_source_id, irq_state);
+ else
+ clear_bit(irq_source_id, irq_state);
+
+ return !!(*irq_state);
+}
+
+static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int irq_source_id, int level)
+{
+#ifdef CONFIG_X86
+ struct kvm_pic *pic = pic_irqchip(kvm);
+ level = kvm_irq_line_state(&pic->irq_states[e->irqchip.pin],
+ irq_source_id, level);
+ return kvm_pic_set_irq(pic, e->irqchip.pin, level);
+#else
+ return -1;
+#endif
+}
+
+static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int irq_source_id, int level)
+{
+ struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+ level = kvm_irq_line_state(&ioapic->irq_states[e->irqchip.pin],
+ irq_source_id, level);
+
+ return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, level);
+}
+
+inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
+{
+#ifdef CONFIG_IA64
+ return irq->delivery_mode ==
+ (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
+#else
+ return irq->delivery_mode == APIC_DM_LOWEST;
+#endif
+}
+
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+ struct kvm_lapic_irq *irq)
+{
+ int i, r = -1;
+ struct kvm_vcpu *vcpu, *lowest = NULL;
+
+ if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
+ kvm_is_dm_lowest_prio(irq))
+ printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ if (!kvm_apic_present(vcpu))
+ continue;
+
+ if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
+ irq->dest_id, irq->dest_mode))
+ continue;
+
+ if (!kvm_is_dm_lowest_prio(irq)) {
+ if (r < 0)
+ r = 0;
+ r += kvm_apic_set_irq(vcpu, irq);
+ } else if (kvm_lapic_enabled(vcpu)) {
+ if (!lowest)
+ lowest = vcpu;
+ else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
+ lowest = vcpu;
+ }
+ }
+
+ if (lowest)
+ r = kvm_apic_set_irq(lowest, irq);
+
+ return r;
+}
+
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int irq_source_id, int level)
+{
+ struct kvm_lapic_irq irq;
+
+ if (!level)
+ return -1;
+
+ trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
+
+ irq.dest_id = (e->msi.address_lo &
+ MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
+ irq.vector = (e->msi.data &
+ MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
+ irq.dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
+ irq.trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
+ irq.delivery_mode = e->msi.data & 0x700;
+ irq.level = 1;
+ irq.shorthand = 0;
+
+ /* TODO Deal with RH bit of MSI message address */
+ return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
+}
+
+/*
+ * Return value:
+ * < 0 Interrupt was ignored (masked or not delivered for other reasons)
+ * = 0 Interrupt was coalesced (previous irq is still pending)
+ * > 0 Number of CPUs interrupt was delivered to
+ */
+int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
+{
+ struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
+ int ret = -1, i = 0;
+ struct kvm_irq_routing_table *irq_rt;
+ struct hlist_node *n;
+
+ trace_kvm_set_irq(irq, level, irq_source_id);
+
+ /* Not possible to detect if the guest uses the PIC or the
+ * IOAPIC. So set the bit in both. The guest will ignore
+ * writes to the unused one.
+ */
+ rcu_read_lock();
+ irq_rt = rcu_dereference(kvm->irq_routing);
+ if (irq < irq_rt->nr_rt_entries)
+ hlist_for_each_entry(e, n, &irq_rt->map[irq], link)
+ irq_set[i++] = *e;
+ rcu_read_unlock();
+
+ while(i--) {
+ int r;
+ r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level);
+ if (r < 0)
+ continue;
+
+ ret = r + ((ret < 0) ? 0 : ret);
+ }
+
+ return ret;
+}
+
+void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
+{
+ struct kvm_irq_ack_notifier *kian;
+ struct hlist_node *n;
+ int gsi;
+
+ trace_kvm_ack_irq(irqchip, pin);
+
+ rcu_read_lock();
+ gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+ if (gsi != -1)
+ hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
+ link)
+ if (kian->gsi == gsi)
+ kian->irq_acked(kian);
+ rcu_read_unlock();
+}
+
+void kvm_register_irq_ack_notifier(struct kvm *kvm,
+ struct kvm_irq_ack_notifier *kian)
+{
+ mutex_lock(&kvm->irq_lock);
+ hlist_add_head_rcu(&kian->link, &kvm->irq_ack_notifier_list);
+ mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
+ struct kvm_irq_ack_notifier *kian)
+{
+ mutex_lock(&kvm->irq_lock);
+ hlist_del_init_rcu(&kian->link);
+ mutex_unlock(&kvm->irq_lock);
+ synchronize_rcu();
+}
+
+int kvm_request_irq_source_id(struct kvm *kvm)
+{
+ unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
+ int irq_source_id;
+
+ mutex_lock(&kvm->irq_lock);
+ irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
+
+ if (irq_source_id >= BITS_PER_LONG) {
+ printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
+ irq_source_id = -EFAULT;
+ goto unlock;
+ }
+
+ ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+ set_bit(irq_source_id, bitmap);
+unlock:
+ mutex_unlock(&kvm->irq_lock);
+
+ return irq_source_id;
+}
+
+void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
+{
+ int i;
+
+ ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
+
+ mutex_lock(&kvm->irq_lock);
+ if (irq_source_id < 0 ||
+ irq_source_id >= BITS_PER_LONG) {
+ printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
+ goto unlock;
+ }
+ clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
+ if (!irqchip_in_kernel(kvm))
+ goto unlock;
+
+ for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++) {
+ clear_bit(irq_source_id, &kvm->arch.vioapic->irq_states[i]);
+ if (i >= 16)
+ continue;
+#ifdef CONFIG_X86
+ clear_bit(irq_source_id, &pic_irqchip(kvm)->irq_states[i]);
+#endif
+ }
+unlock:
+ mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
+ struct kvm_irq_mask_notifier *kimn)
+{
+ mutex_lock(&kvm->irq_lock);
+ kimn->irq = irq;
+ hlist_add_head_rcu(&kimn->link, &kvm->mask_notifier_list);
+ mutex_unlock(&kvm->irq_lock);
+}
+
+void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
+ struct kvm_irq_mask_notifier *kimn)
+{
+ mutex_lock(&kvm->irq_lock);
+ hlist_del_rcu(&kimn->link);
+ mutex_unlock(&kvm->irq_lock);
+ synchronize_rcu();
+}
+
+void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
+ bool mask)
+{
+ struct kvm_irq_mask_notifier *kimn;
+ struct hlist_node *n;
+ int gsi;
+
+ rcu_read_lock();
+ gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+ if (gsi != -1)
+ hlist_for_each_entry_rcu(kimn, n, &kvm->mask_notifier_list, link)
+ if (kimn->irq == gsi)
+ kimn->func(kimn, mask);
+ rcu_read_unlock();
+}
+
+void kvm_free_irq_routing(struct kvm *kvm)
+{
+ /* Called only during vm destruction. Nobody can use the pointer
+ at this stage */
+ kfree(kvm->irq_routing);
+}
+
+static int setup_routing_entry(struct kvm_irq_routing_table *rt,
+ struct kvm_kernel_irq_routing_entry *e,
+ const struct kvm_irq_routing_entry *ue)
+{
+ int r = -EINVAL;
+ int delta;
+ unsigned max_pin;
+ struct kvm_kernel_irq_routing_entry *ei;
+ struct hlist_node *n;
+
+ /*
+ * Do not allow GSI to be mapped to the same irqchip more than once.
+ * Allow only one to one mapping between GSI and MSI.
+ */
+ hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link)
+ if (ei->type == KVM_IRQ_ROUTING_MSI ||
+ ue->u.irqchip.irqchip == ei->irqchip.irqchip)
+ return r;
+
+ e->gsi = ue->gsi;
+ e->type = ue->type;
+ switch (ue->type) {
+ case KVM_IRQ_ROUTING_IRQCHIP:
+ delta = 0;
+ switch (ue->u.irqchip.irqchip) {
+ case KVM_IRQCHIP_PIC_MASTER:
+ e->set = kvm_set_pic_irq;
+ max_pin = 16;
+ break;
+ case KVM_IRQCHIP_PIC_SLAVE:
+ e->set = kvm_set_pic_irq;
+ max_pin = 16;
+ delta = 8;
+ break;
+ case KVM_IRQCHIP_IOAPIC:
+ max_pin = KVM_IOAPIC_NUM_PINS;
+ e->set = kvm_set_ioapic_irq;
+ break;
+ default:
+ goto out;
+ }
+ e->irqchip.irqchip = ue->u.irqchip.irqchip;
+ e->irqchip.pin = ue->u.irqchip.pin + delta;
+ if (e->irqchip.pin >= max_pin)
+ goto out;
+ rt->chip[ue->u.irqchip.irqchip][e->irqchip.pin] = ue->gsi;
+ break;
+ case KVM_IRQ_ROUTING_MSI:
+ e->set = kvm_set_msi;
+ e->msi.address_lo = ue->u.msi.address_lo;
+ e->msi.address_hi = ue->u.msi.address_hi;
+ e->msi.data = ue->u.msi.data;
+ break;
+ default:
+ goto out;
+ }
+
+ hlist_add_head(&e->link, &rt->map[e->gsi]);
+ r = 0;
+out:
+ return r;
+}
+
+
+int kvm_set_irq_routing(struct kvm *kvm,
+ const struct kvm_irq_routing_entry *ue,
+ unsigned nr,
+ unsigned flags)
+{
+ struct kvm_irq_routing_table *new, *old;
+ u32 i, j, nr_rt_entries = 0;
+ int r;
+
+ for (i = 0; i < nr; ++i) {
+ if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
+ return -EINVAL;
+ nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
+ }
+
+ nr_rt_entries += 1;
+
+ new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head))
+ + (nr * sizeof(struct kvm_kernel_irq_routing_entry)),
+ GFP_KERNEL);
+
+ if (!new)
+ return -ENOMEM;
+
+ new->rt_entries = (void *)&new->map[nr_rt_entries];
+
+ new->nr_rt_entries = nr_rt_entries;
+ for (i = 0; i < 3; i++)
+ for (j = 0; j < KVM_IOAPIC_NUM_PINS; j++)
+ new->chip[i][j] = -1;
+
+ for (i = 0; i < nr; ++i) {
+ r = -EINVAL;
+ if (ue->flags)
+ goto out;
+ r = setup_routing_entry(new, &new->rt_entries[i], ue);
+ if (r)
+ goto out;
+ ++ue;
+ }
+
+ mutex_lock(&kvm->irq_lock);
+ old = kvm->irq_routing;
+ kvm_irq_routing_update(kvm, new);
+ mutex_unlock(&kvm->irq_lock);
+
+ synchronize_rcu();
+
+ new = old;
+ r = 0;
+
+out:
+ kfree(new);
+ return r;
+}
+
+#define IOAPIC_ROUTING_ENTRY(irq) \
+ { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \
+ .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
+#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
+
+#ifdef CONFIG_X86
+# define PIC_ROUTING_ENTRY(irq) \
+ { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \
+ .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
+# define ROUTING_ENTRY2(irq) \
+ IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
+#else
+# define ROUTING_ENTRY2(irq) \
+ IOAPIC_ROUTING_ENTRY(irq)
+#endif
+
+static const struct kvm_irq_routing_entry default_routing[] = {
+ ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
+ ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
+ ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
+ ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
+ ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
+ ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
+ ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
+ ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
+ ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
+ ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
+ ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
+ ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
+#ifdef CONFIG_IA64
+ ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
+ ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
+ ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
+ ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
+ ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
+ ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
+ ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
+ ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
+ ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
+ ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
+ ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
+ ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
+#endif
+};
+
+int kvm_setup_default_irq_routing(struct kvm *kvm)
+{
+ return kvm_set_irq_routing(kvm, default_routing,
+ ARRAY_SIZE(default_routing), 0);
+}