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-rw-r--r--virt/kvm/irqchip.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
new file mode 100644
index 0000000000..1e567d1f6d
--- /dev/null
+++ b/virt/kvm/irqchip.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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 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>
+
+int kvm_irq_map_gsi(struct kvm *kvm,
+ struct kvm_kernel_irq_routing_entry *entries, int gsi)
+{
+ struct kvm_irq_routing_table *irq_rt;
+ struct kvm_kernel_irq_routing_entry *e;
+ int n = 0;
+
+ irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu,
+ lockdep_is_held(&kvm->irq_lock));
+ if (irq_rt && gsi < irq_rt->nr_rt_entries) {
+ hlist_for_each_entry(e, &irq_rt->map[gsi], link) {
+ entries[n] = *e;
+ ++n;
+ }
+ }
+
+ return n;
+}
+
+int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin)
+{
+ struct kvm_irq_routing_table *irq_rt;
+
+ irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
+ return irq_rt->chip[irqchip][pin];
+}
+
+int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
+{
+ struct kvm_kernel_irq_routing_entry route;
+
+ if (!kvm_arch_irqchip_in_kernel(kvm) || (msi->flags & ~KVM_MSI_VALID_DEVID))
+ return -EINVAL;
+
+ route.msi.address_lo = msi->address_lo;
+ route.msi.address_hi = msi->address_hi;
+ route.msi.data = msi->data;
+ route.msi.flags = msi->flags;
+ route.msi.devid = msi->devid;
+
+ 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 irq_set[KVM_NR_IRQCHIPS];
+ int ret = -1, i, idx;
+
+ 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);
+ i = kvm_irq_map_gsi(kvm, irq_set, irq);
+ 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;
+}
+
+static void free_irq_routing_table(struct kvm_irq_routing_table *rt)
+{
+ int i;
+
+ if (!rt)
+ return;
+
+ for (i = 0; i < rt->nr_rt_entries; ++i) {
+ struct kvm_kernel_irq_routing_entry *e;
+ struct hlist_node *n;
+
+ hlist_for_each_entry_safe(e, n, &rt->map[i], link) {
+ hlist_del(&e->link);
+ kfree(e);
+ }
+ }
+
+ kfree(rt);
+}
+
+void kvm_free_irq_routing(struct kvm *kvm)
+{
+ /* Called only during vm destruction. Nobody can use the pointer
+ at this stage */
+ struct kvm_irq_routing_table *rt = rcu_access_pointer(kvm->irq_routing);
+ free_irq_routing_table(rt);
+}
+
+static int setup_routing_entry(struct kvm *kvm,
+ struct kvm_irq_routing_table *rt,
+ struct kvm_kernel_irq_routing_entry *e,
+ const struct kvm_irq_routing_entry *ue)
+{
+ struct kvm_kernel_irq_routing_entry *ei;
+ int r;
+ u32 gsi = array_index_nospec(ue->gsi, KVM_MAX_IRQ_ROUTES);
+
+ /*
+ * Do not allow GSI to be mapped to the same irqchip more than once.
+ * Allow only one to one mapping between GSI and non-irqchip routing.
+ */
+ hlist_for_each_entry(ei, &rt->map[gsi], link)
+ if (ei->type != KVM_IRQ_ROUTING_IRQCHIP ||
+ ue->type != KVM_IRQ_ROUTING_IRQCHIP ||
+ ue->u.irqchip.irqchip == ei->irqchip.irqchip)
+ return -EINVAL;
+
+ e->gsi = gsi;
+ e->type = ue->type;
+ r = kvm_set_routing_entry(kvm, e, ue);
+ if (r)
+ return r;
+ if (e->type == KVM_IRQ_ROUTING_IRQCHIP)
+ rt->chip[e->irqchip.irqchip][e->irqchip.pin] = e->gsi;
+
+ hlist_add_head(&e->link, &rt->map[e->gsi]);
+
+ return 0;
+}
+
+void __attribute__((weak)) kvm_arch_irq_routing_update(struct kvm *kvm)
+{
+}
+
+bool __weak kvm_arch_can_set_irq_routing(struct kvm *kvm)
+{
+ return true;
+}
+
+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;
+ struct kvm_kernel_irq_routing_entry *e;
+ 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(struct_size(new, map, nr_rt_entries), GFP_KERNEL_ACCOUNT);
+ if (!new)
+ return -ENOMEM;
+
+ 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 = -ENOMEM;
+ e = kzalloc(sizeof(*e), GFP_KERNEL_ACCOUNT);
+ if (!e)
+ goto out;
+
+ r = -EINVAL;
+ switch (ue->type) {
+ case KVM_IRQ_ROUTING_MSI:
+ if (ue->flags & ~KVM_MSI_VALID_DEVID)
+ goto free_entry;
+ break;
+ default:
+ if (ue->flags)
+ goto free_entry;
+ break;
+ }
+ r = setup_routing_entry(kvm, new, e, ue);
+ if (r)
+ goto free_entry;
+ ++ue;
+ }
+
+ mutex_lock(&kvm->irq_lock);
+ old = rcu_dereference_protected(kvm->irq_routing, 1);
+ rcu_assign_pointer(kvm->irq_routing, new);
+ kvm_irq_routing_update(kvm);
+ kvm_arch_irq_routing_update(kvm);
+ mutex_unlock(&kvm->irq_lock);
+
+ kvm_arch_post_irq_routing_update(kvm);
+
+ synchronize_srcu_expedited(&kvm->irq_srcu);
+
+ new = old;
+ r = 0;
+ goto out;
+
+free_entry:
+ kfree(e);
+out:
+ free_irq_routing_table(new);
+
+ return r;
+}