/* * 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 * * 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 * Alexander Graf */ #include #include #include #include #include #include "irq.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 (!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; /* * 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[ue->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 = ue->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(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head)), GFP_KERNEL); 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); 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; }