diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /virt/kvm/irqchip.c |
Initial import
Diffstat (limited to 'virt/kvm/irqchip.c')
-rw-r--r-- | virt/kvm/irqchip.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c new file mode 100644 index 000000000..1d56a901e --- /dev/null +++ b/virt/kvm/irqchip.c @@ -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; +} |