KVM: Extract generic irqchip logic into irqchip.c

The current irq_comm.c file contains pieces of code that are generic
across different irqchip implementations, as well as code that is
fully IOAPIC specific.

Split the generic bits out into irqchip.c.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 152 insertions, 0 deletions

diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
new file mode 100644
index 000000000000..12f7f26af4f8
--- /dev/null
+++ b/virt/kvm/irqchip.c
@@ -0,0 +1,152 @@
+/*
+ * 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/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;
+
+        rcu_read_lock();
+        gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+        if (gsi != -1)
+                hlist_for_each_entry_rcu(kian, &kvm->irq_ack_notifier_list,
+                                         link)
+                        if (kian->gsi == gsi) {
+                                rcu_read_unlock();
+                                return true;
+                        }
+
+        rcu_read_unlock();
+
+        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;
+
+        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, &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);
+#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_rcu();
+#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;
+        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.
+         */
+        rcu_read_lock();
+        irq_rt = rcu_dereference(kvm->irq_routing);
+        if (irq < irq_rt->nr_rt_entries)
+                hlist_for_each_entry(e, &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,
+                                   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);
+}