diff options
Diffstat (limited to 'arch/x86/kvm/irq_comm.c')
-rw-r--r-- | arch/x86/kvm/irq_comm.c | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c new file mode 100644 index 0000000..e9c135b --- /dev/null +++ b/arch/x86/kvm/irq_comm.c @@ -0,0 +1,347 @@ +/* + * irq_comm.c: Common API for in kernel interrupt controller + * Copyright (c) 2007, Intel Corporation. + * + * 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. + * Authors: + * Yaozu (Eddie) Dong <Eddie.dong@intel.com> + * + * Copyright 2010 Red Hat, Inc. and/or its affiliates. + */ + +#include <linux/kvm_host.h> +#include <linux/slab.h> +#include <linux/export.h> +#include <trace/events/kvm.h> + +#include <asm/msidef.h> + +#include "irq.h" + +#include "ioapic.h" + +static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, int level, + bool line_status) +{ +#ifdef CONFIG_X86 + struct kvm_pic *pic = pic_irqchip(kvm); + return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level); +#else + return -1; +#endif +} + +static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, int level, + bool line_status) +{ + struct kvm_ioapic *ioapic = kvm->arch.vioapic; + return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level, + line_status); +} + +inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq) +{ + return irq->delivery_mode == APIC_DM_LOWEST; +} + +int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src, + struct kvm_lapic_irq *irq, unsigned long *dest_map) +{ + int i, r = -1; + struct kvm_vcpu *vcpu, *lowest = NULL; + + if (irq->dest_mode == 0 && irq->dest_id == 0xff && + kvm_is_dm_lowest_prio(irq)) { + printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n"); + irq->delivery_mode = APIC_DM_FIXED; + } + + if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map)) + return r; + + kvm_for_each_vcpu(i, vcpu, kvm) { + if (!kvm_apic_present(vcpu)) + continue; + + if (!kvm_apic_match_dest(vcpu, src, irq->shorthand, + irq->dest_id, irq->dest_mode)) + continue; + + if (!kvm_is_dm_lowest_prio(irq)) { + if (r < 0) + r = 0; + r += kvm_apic_set_irq(vcpu, irq, dest_map); + } else if (kvm_lapic_enabled(vcpu)) { + if (!lowest) + lowest = vcpu; + else if (kvm_apic_compare_prio(vcpu, lowest) < 0) + lowest = vcpu; + } + } + + if (lowest) + r = kvm_apic_set_irq(lowest, irq, dest_map); + + return r; +} + +static inline void kvm_set_msi_irq(struct kvm_kernel_irq_routing_entry *e, + struct kvm_lapic_irq *irq) +{ + trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data); + + irq->dest_id = (e->msi.address_lo & + MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT; + irq->vector = (e->msi.data & + MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT; + irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo; + irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data; + irq->delivery_mode = e->msi.data & 0x700; + irq->level = 1; + irq->shorthand = 0; + /* TODO Deal with RH bit of MSI message address */ +} + +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, int level, bool line_status) +{ + struct kvm_lapic_irq irq; + + if (!level) + return -1; + + kvm_set_msi_irq(e, &irq); + + return kvm_irq_delivery_to_apic(kvm, NULL, &irq, NULL); +} + + +static int kvm_set_msi_inatomic(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm) +{ + struct kvm_lapic_irq irq; + int r; + + kvm_set_msi_irq(e, &irq); + + if (kvm_irq_delivery_to_apic_fast(kvm, NULL, &irq, &r, NULL)) + return r; + else + return -EWOULDBLOCK; +} + +/* + * Deliver an IRQ in an atomic context if we can, or return a failure, + * user can retry in a process context. + * Return value: + * -EWOULDBLOCK - Can't deliver in atomic context: retry in a process context. + * Other values - No need to retry. + */ +int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level) +{ + struct kvm_kernel_irq_routing_entry entries[KVM_NR_IRQCHIPS]; + struct kvm_kernel_irq_routing_entry *e; + int ret = -EINVAL; + int idx; + + trace_kvm_set_irq(irq, level, irq_source_id); + + /* + * Injection into either PIC or IOAPIC might need to scan all CPUs, + * which would need to be retried from thread context; when same GSI + * is connected to both PIC and IOAPIC, we'd have to report a + * partial failure here. + * Since there's no easy way to do this, we only support injecting MSI + * which is limited to 1:1 GSI mapping. + */ + idx = srcu_read_lock(&kvm->irq_srcu); + if (kvm_irq_map_gsi(kvm, entries, irq) > 0) { + e = &entries[0]; + if (likely(e->type == KVM_IRQ_ROUTING_MSI)) + ret = kvm_set_msi_inatomic(e, kvm); + else + ret = -EWOULDBLOCK; + } + srcu_read_unlock(&kvm->irq_srcu, idx); + return ret; +} + +int kvm_request_irq_source_id(struct kvm *kvm) +{ + unsigned long *bitmap = &kvm->arch.irq_sources_bitmap; + int irq_source_id; + + mutex_lock(&kvm->irq_lock); + irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG); + + if (irq_source_id >= BITS_PER_LONG) { + printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n"); + irq_source_id = -EFAULT; + goto unlock; + } + + ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID); +#ifdef CONFIG_X86 + ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID); +#endif + set_bit(irq_source_id, bitmap); +unlock: + mutex_unlock(&kvm->irq_lock); + + return irq_source_id; +} + +void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id) +{ + ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID); +#ifdef CONFIG_X86 + ASSERT(irq_source_id != KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID); +#endif + + mutex_lock(&kvm->irq_lock); + if (irq_source_id < 0 || + irq_source_id >= BITS_PER_LONG) { + printk(KERN_ERR "kvm: IRQ source ID out of range!\n"); + goto unlock; + } + clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap); + if (!irqchip_in_kernel(kvm)) + goto unlock; + + kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id); +#ifdef CONFIG_X86 + kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id); +#endif +unlock: + mutex_unlock(&kvm->irq_lock); +} + +void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq, + struct kvm_irq_mask_notifier *kimn) +{ + mutex_lock(&kvm->irq_lock); + kimn->irq = irq; + hlist_add_head_rcu(&kimn->link, &kvm->arch.mask_notifier_list); + mutex_unlock(&kvm->irq_lock); +} + +void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq, + struct kvm_irq_mask_notifier *kimn) +{ + mutex_lock(&kvm->irq_lock); + hlist_del_rcu(&kimn->link); + mutex_unlock(&kvm->irq_lock); + synchronize_srcu(&kvm->irq_srcu); +} + +void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin, + bool mask) +{ + struct kvm_irq_mask_notifier *kimn; + int idx, gsi; + + idx = srcu_read_lock(&kvm->irq_srcu); + gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin); + if (gsi != -1) + hlist_for_each_entry_rcu(kimn, &kvm->arch.mask_notifier_list, link) + if (kimn->irq == gsi) + kimn->func(kimn, mask); + srcu_read_unlock(&kvm->irq_srcu, idx); +} + +int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e, + const struct kvm_irq_routing_entry *ue) +{ + int r = -EINVAL; + int delta; + unsigned max_pin; + + switch (ue->type) { + case KVM_IRQ_ROUTING_IRQCHIP: + delta = 0; + switch (ue->u.irqchip.irqchip) { + case KVM_IRQCHIP_PIC_MASTER: + e->set = kvm_set_pic_irq; + max_pin = PIC_NUM_PINS; + break; + case KVM_IRQCHIP_PIC_SLAVE: + e->set = kvm_set_pic_irq; + max_pin = PIC_NUM_PINS; + delta = 8; + break; + case KVM_IRQCHIP_IOAPIC: + max_pin = KVM_IOAPIC_NUM_PINS; + e->set = kvm_set_ioapic_irq; + break; + default: + goto out; + } + e->irqchip.irqchip = ue->u.irqchip.irqchip; + e->irqchip.pin = ue->u.irqchip.pin + delta; + if (e->irqchip.pin >= max_pin) + goto out; + break; + case KVM_IRQ_ROUTING_MSI: + e->set = kvm_set_msi; + e->msi.address_lo = ue->u.msi.address_lo; + e->msi.address_hi = ue->u.msi.address_hi; + e->msi.data = ue->u.msi.data; + break; + default: + goto out; + } + + r = 0; +out: + return r; +} + +#define IOAPIC_ROUTING_ENTRY(irq) \ + { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ + .u.irqchip = { .irqchip = KVM_IRQCHIP_IOAPIC, .pin = (irq) } } +#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq) + +#ifdef CONFIG_X86 +# define PIC_ROUTING_ENTRY(irq) \ + { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ + .u.irqchip = { .irqchip = SELECT_PIC(irq), .pin = (irq) % 8 } } +# define ROUTING_ENTRY2(irq) \ + IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq) +#else +# define ROUTING_ENTRY2(irq) \ + IOAPIC_ROUTING_ENTRY(irq) +#endif + +static const struct kvm_irq_routing_entry default_routing[] = { + ROUTING_ENTRY2(0), ROUTING_ENTRY2(1), + ROUTING_ENTRY2(2), ROUTING_ENTRY2(3), + ROUTING_ENTRY2(4), ROUTING_ENTRY2(5), + ROUTING_ENTRY2(6), ROUTING_ENTRY2(7), + ROUTING_ENTRY2(8), ROUTING_ENTRY2(9), + ROUTING_ENTRY2(10), ROUTING_ENTRY2(11), + ROUTING_ENTRY2(12), ROUTING_ENTRY2(13), + ROUTING_ENTRY2(14), ROUTING_ENTRY2(15), + ROUTING_ENTRY1(16), ROUTING_ENTRY1(17), + ROUTING_ENTRY1(18), ROUTING_ENTRY1(19), + ROUTING_ENTRY1(20), ROUTING_ENTRY1(21), + ROUTING_ENTRY1(22), ROUTING_ENTRY1(23), +}; + +int kvm_setup_default_irq_routing(struct kvm *kvm) +{ + return kvm_set_irq_routing(kvm, default_routing, + ARRAY_SIZE(default_routing), 0); +} |