Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / virt / kvm / irqchip.c
diff --git a/kernel/virt/kvm/irqchip.c b/kernel/virt/kvm/irqchip.c
new file mode 100644 (file)
index 0000000..1d56a90
--- /dev/null
@@ -0,0 +1,214 @@
+/*
+ * 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"
+
+struct kvm_irq_routing_table {
+       int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
+       struct kvm_kernel_irq_routing_entry *rt_entries;
+       u32 nr_rt_entries;
+       /*
+        * Array indexed by gsi. Each entry contains list of irq chips
+        * the gsi is connected to.
+        */
+       struct hlist_head map[0];
+};
+
+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 (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 (!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 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;
+}
+
+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(e, ue);
+       if (r)
+               goto out;
+       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]);
+       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;
+       rcu_assign_pointer(kvm->irq_routing, new);
+       kvm_irq_routing_update(kvm);
+       mutex_unlock(&kvm->irq_lock);
+
+       synchronize_srcu_expedited(&kvm->irq_srcu);
+
+       new = old;
+       r = 0;
+
+out:
+       kfree(new);
+       return r;
+}