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-rw-r--r--virt/kvm/irqchip.c238
1 files changed, 238 insertions, 0 deletions
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
new file mode 100644
index 00000000000..b43c275775c
--- /dev/null
+++ b/virt/kvm/irqchip.c
@@ -0,0 +1,238 @@
+/*
+ * irqchip.c: Common API for in kernel interrupt controllers
+ * Copyright (c) 2007, Intel Corporation.
+ * Copyright 2010 Red Hat, Inc. and/or its affiliates.
+ * Copyright (c) 2013, Alexander Graf <agraf@suse.de>
+ *
+ * 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.
+ *
+ * This file is derived from virt/kvm/irq_comm.c.
+ *
+ * Authors:
+ * Yaozu (Eddie) Dong <Eddie.dong@intel.com>
+ * Alexander Graf <agraf@suse.de>
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/slab.h>
+#include <linux/srcu.h>
+#include <linux/export.h>
+#include <trace/events/kvm.h>
+#include "irq.h"
+
+bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin)
+{
+ struct kvm_irq_ack_notifier *kian;
+ int gsi, idx;
+
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ gsi = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu)->chip[irqchip][pin];
+ if (gsi != -1)
+ hlist_for_each_entry_rcu(kian, &kvm->irq_ack_notifier_list,
+ link)
+ if (kian->gsi == gsi) {
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+ return true;
+ }
+
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(kvm_irq_has_notifier);
+
+void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
+{
+ struct kvm_irq_ack_notifier *kian;
+ int gsi, idx;
+
+ trace_kvm_ack_irq(irqchip, pin);
+
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ gsi = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu)->chip[irqchip][pin];
+ if (gsi != -1)
+ hlist_for_each_entry_rcu(kian, &kvm->irq_ack_notifier_list,
+ link)
+ if (kian->gsi == gsi)
+ kian->irq_acked(kian);
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+}
+
+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);
+#ifdef __KVM_HAVE_IOAPIC
+ kvm_vcpu_request_scan_ioapic(kvm);
+#endif
+}
+
+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_srcu(&kvm->irq_srcu);
+#ifdef __KVM_HAVE_IOAPIC
+ kvm_vcpu_request_scan_ioapic(kvm);
+#endif
+}
+
+int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
+{
+ struct kvm_kernel_irq_routing_entry route;
+
+ if (!irqchip_in_kernel(kvm) || msi->flags != 0)
+ return -EINVAL;
+
+ route.msi.address_lo = msi->address_lo;
+ route.msi.address_hi = msi->address_hi;
+ route.msi.data = msi->data;
+
+ return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1, false);
+}
+
+/*
+ * 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,
+ bool line_status)
+{
+ struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
+ int ret = -1, i = 0, idx;
+ struct kvm_irq_routing_table *irq_rt;
+
+ 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.
+ */
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
+ if (irq < irq_rt->nr_rt_entries)
+ hlist_for_each_entry(e, &irq_rt->map[irq], link)
+ irq_set[i++] = *e;
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+
+ while(i--) {
+ int r;
+ r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level,
+ line_status);
+ if (r < 0)
+ continue;
+
+ ret = r + ((ret < 0) ? 0 : ret);
+ }
+
+ return ret;
+}
+
+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;
+ struct kvm_kernel_irq_routing_entry *ei;
+
+ /*
+ * 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, &rt->map[ue->gsi], link)
+ if (ei->type == KVM_IRQ_ROUTING_MSI ||
+ ue->type == KVM_IRQ_ROUTING_MSI ||
+ ue->u.irqchip.irqchip == ei->irqchip.irqchip)
+ return r;
+
+ e->gsi = ue->gsi;
+ e->type = ue->type;
+ r = kvm_set_routing_entry(rt, e, ue);
+ if (r)
+ 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 < KVM_NR_IRQCHIPS; i++)
+ for (j = 0; j < KVM_IRQCHIP_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_srcu_expedited(&kvm->irq_srcu);
+
+ new = old;
+ r = 0;
+
+out:
+ kfree(new);
+ return r;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 13:18:47 +0000