From: Avi Kivity Date: Wed, 19 Nov 2008 11:58:46 +0000 (+0200) Subject: KVM: Userspace controlled irq routing X-Git-Tag: v2.6.30-rc1~664^2~37 X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=399ec807ddc38ecccf8c06dbde04531cbdc63e11 KVM: Userspace controlled irq routing Currently KVM has a static routing from GSI numbers to interrupts (namely, 0-15 are mapped 1:1 to both PIC and IOAPIC, and 16:23 are mapped 1:1 to the IOAPIC). This is insufficient for several reasons: - HPET requires non 1:1 mapping for the timer interrupt - MSIs need a new method to assign interrupt numbers and dispatch them - ACPI APIC mode needs to be able to reassign the PCI LINK interrupts to the ioapics This patch implements an interrupt routing table (as a linked list, but this can be easily changed) and a userspace interface to replace the table. The routing table is initialized according to the current hardwired mapping. Signed-off-by: Avi Kivity --- diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index 1477f91..dbf527a 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -919,6 +919,11 @@ long kvm_arch_vm_ioctl(struct file *filp, r = kvm_ioapic_init(kvm); if (r) goto out; + r = kvm_setup_default_irq_routing(kvm); + if (r) { + kfree(kvm->arch.vioapic); + goto out; + } break; case KVM_IRQ_LINE: { struct kvm_irq_level irq_event; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 141a016..32e3a7e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1835,6 +1835,12 @@ long kvm_arch_vm_ioctl(struct file *filp, } } else goto out; + r = kvm_setup_default_irq_routing(kvm); + if (r) { + kfree(kvm->arch.vpic); + kfree(kvm->arch.vioapic); + goto out; + } break; case KVM_CREATE_PIT: mutex_lock(&kvm->lock); diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 73f3480..7a5d73a 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -399,6 +399,38 @@ struct kvm_trace_rec { #if defined(CONFIG_X86) #define KVM_CAP_REINJECT_CONTROL 24 #endif +#if defined(CONFIG_X86)||defined(CONFIG_IA64) +#define KVM_CAP_IRQ_ROUTING 25 +#endif + +#ifdef KVM_CAP_IRQ_ROUTING + +struct kvm_irq_routing_irqchip { + __u32 irqchip; + __u32 pin; +}; + +/* gsi routing entry types */ +#define KVM_IRQ_ROUTING_IRQCHIP 1 + +struct kvm_irq_routing_entry { + __u32 gsi; + __u32 type; + __u32 flags; + __u32 pad; + union { + struct kvm_irq_routing_irqchip irqchip; + __u32 pad[8]; + } u; +}; + +struct kvm_irq_routing { + __u32 nr; + __u32 flags; + struct kvm_irq_routing_entry entries[0]; +}; + +#endif /* * ioctls for VM fds @@ -430,6 +462,7 @@ struct kvm_trace_rec { _IOW(KVMIO, 0x68, struct kvm_coalesced_mmio_zone) #define KVM_ASSIGN_PCI_DEVICE _IOR(KVMIO, 0x69, \ struct kvm_assigned_pci_dev) +#define KVM_SET_GSI_ROUTING _IOW(KVMIO, 0x6a, struct kvm_irq_routing) #define KVM_ASSIGN_IRQ _IOR(KVMIO, 0x70, \ struct kvm_assigned_irq) #define KVM_REINJECT_CONTROL _IO(KVMIO, 0x71) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 99963f3..ce285e0 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -107,6 +107,19 @@ struct kvm_memory_slot { int user_alloc; }; +struct kvm_kernel_irq_routing_entry { + u32 gsi; + void (*set)(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int level); + union { + struct { + unsigned irqchip; + unsigned pin; + } irqchip; + }; + struct list_head link; +}; + struct kvm { struct mutex lock; /* protects the vcpus array and APIC accesses */ spinlock_t mmu_lock; @@ -128,6 +141,7 @@ struct kvm { #endif #ifdef CONFIG_HAVE_KVM_IRQCHIP + struct list_head irq_routing; /* of kvm_kernel_irq_routing_entry */ struct hlist_head mask_notifier_list; #endif @@ -480,4 +494,21 @@ static inline int mmu_notifier_retry(struct kvm_vcpu *vcpu, unsigned long mmu_se } #endif +#ifdef CONFIG_HAVE_KVM_IRQCHIP + +#define KVM_MAX_IRQ_ROUTES 1024 + +int kvm_setup_default_irq_routing(struct kvm *kvm); +int kvm_set_irq_routing(struct kvm *kvm, + const struct kvm_irq_routing_entry *entries, + unsigned nr, + unsigned flags); +void kvm_free_irq_routing(struct kvm *kvm); + +#else + +static inline void kvm_free_irq_routing(struct kvm *kvm) {} + +#endif + #endif diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index 5162a41..a797fa5 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -24,9 +24,24 @@ #include "ioapic.h" +static void kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int level) +{ +#ifdef CONFIG_X86 + kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level); +#endif +} + +static void kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int level) +{ + kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level); +} + /* This should be called with the kvm->lock mutex held */ void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level) { + struct kvm_kernel_irq_routing_entry *e; unsigned long *irq_state = (unsigned long *)&kvm->arch.irq_states[irq]; /* Logical OR for level trig interrupt */ @@ -39,10 +54,9 @@ void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level) * IOAPIC. So set the bit in both. The guest will ignore * writes to the unused one. */ - kvm_ioapic_set_irq(kvm->arch.vioapic, irq, !!(*irq_state)); -#ifdef CONFIG_X86 - kvm_pic_set_irq(pic_irqchip(kvm), irq, !!(*irq_state)); -#endif + list_for_each_entry(e, &kvm->irq_routing, link) + if (e->gsi == irq) + e->set(e, kvm, !!(*irq_state)); } void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi) @@ -123,3 +137,149 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask) kimn->func(kimn, mask); } +static void __kvm_free_irq_routing(struct list_head *irq_routing) +{ + struct kvm_kernel_irq_routing_entry *e, *n; + + list_for_each_entry_safe(e, n, irq_routing, link) + kfree(e); +} + +void kvm_free_irq_routing(struct kvm *kvm) +{ + __kvm_free_irq_routing(&kvm->irq_routing); +} + +int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e, + const struct kvm_irq_routing_entry *ue) +{ + int r = -EINVAL; + int delta; + + e->gsi = ue->gsi; + 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; + break; + case KVM_IRQCHIP_PIC_SLAVE: + e->set = kvm_set_pic_irq; + delta = 8; + break; + case KVM_IRQCHIP_IOAPIC: + 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; + break; + default: + goto out; + } + 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 list_head irq_list = LIST_HEAD_INIT(irq_list); + struct list_head tmp = LIST_HEAD_INIT(tmp); + struct kvm_kernel_irq_routing_entry *e = NULL; + unsigned i; + int r; + + for (i = 0; i < nr; ++i) { + r = -EINVAL; + if (ue->gsi >= KVM_MAX_IRQ_ROUTES) + goto out; + if (ue->flags) + goto out; + r = -ENOMEM; + e = kzalloc(sizeof(*e), GFP_KERNEL); + if (!e) + goto out; + r = setup_routing_entry(e, ue); + if (r) + goto out; + ++ue; + list_add(&e->link, &irq_list); + e = NULL; + } + + mutex_lock(&kvm->lock); + list_splice(&kvm->irq_routing, &tmp); + INIT_LIST_HEAD(&kvm->irq_routing); + list_splice(&irq_list, &kvm->irq_routing); + INIT_LIST_HEAD(&irq_list); + list_splice(&tmp, &irq_list); + mutex_unlock(&kvm->lock); + + r = 0; + +out: + kfree(e); + __kvm_free_irq_routing(&irq_list); + return r; +} + +#define IOAPIC_ROUTING_ENTRY(irq) \ + { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ + .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) } +#define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq) + +#ifdef CONFIG_X86 +#define SELECT_PIC(irq) \ + ((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE) +# define PIC_ROUTING_ENTRY(irq) \ + { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP, \ + .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.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), +#ifdef CONFIG_IA64 + ROUTING_ENTRY1(24), ROUTING_ENTRY1(25), + ROUTING_ENTRY1(26), ROUTING_ENTRY1(27), + ROUTING_ENTRY1(28), ROUTING_ENTRY1(29), + ROUTING_ENTRY1(30), ROUTING_ENTRY1(31), + ROUTING_ENTRY1(32), ROUTING_ENTRY1(33), + ROUTING_ENTRY1(34), ROUTING_ENTRY1(35), + ROUTING_ENTRY1(36), ROUTING_ENTRY1(37), + ROUTING_ENTRY1(38), ROUTING_ENTRY1(39), + ROUTING_ENTRY1(40), ROUTING_ENTRY1(41), + ROUTING_ENTRY1(42), ROUTING_ENTRY1(43), + ROUTING_ENTRY1(44), ROUTING_ENTRY1(45), + ROUTING_ENTRY1(46), ROUTING_ENTRY1(47), +#endif +}; + +int kvm_setup_default_irq_routing(struct kvm *kvm) +{ + return kvm_set_irq_routing(kvm, default_routing, + ARRAY_SIZE(default_routing), 0); +} diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 786a3ae..c65484b 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -843,6 +843,7 @@ static struct kvm *kvm_create_vm(void) if (IS_ERR(kvm)) goto out; #ifdef CONFIG_HAVE_KVM_IRQCHIP + INIT_LIST_HEAD(&kvm->irq_routing); INIT_HLIST_HEAD(&kvm->mask_notifier_list); #endif @@ -926,6 +927,7 @@ static void kvm_destroy_vm(struct kvm *kvm) spin_lock(&kvm_lock); list_del(&kvm->vm_list); spin_unlock(&kvm_lock); + kvm_free_irq_routing(kvm); kvm_io_bus_destroy(&kvm->pio_bus); kvm_io_bus_destroy(&kvm->mmio_bus); #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET @@ -1946,6 +1948,36 @@ static long kvm_vm_ioctl(struct file *filp, break; } #endif +#ifdef KVM_CAP_IRQ_ROUTING + case KVM_SET_GSI_ROUTING: { + struct kvm_irq_routing routing; + struct kvm_irq_routing __user *urouting; + struct kvm_irq_routing_entry *entries; + + r = -EFAULT; + if (copy_from_user(&routing, argp, sizeof(routing))) + goto out; + r = -EINVAL; + if (routing.nr >= KVM_MAX_IRQ_ROUTES) + goto out; + if (routing.flags) + goto out; + r = -ENOMEM; + entries = vmalloc(routing.nr * sizeof(*entries)); + if (!entries) + goto out; + r = -EFAULT; + urouting = argp; + if (copy_from_user(entries, urouting->entries, + routing.nr * sizeof(*entries))) + goto out_free_irq_routing; + r = kvm_set_irq_routing(kvm, entries, routing.nr, + routing.flags); + out_free_irq_routing: + vfree(entries); + break; + } +#endif default: r = kvm_arch_vm_ioctl(filp, ioctl, arg); } @@ -2012,6 +2044,10 @@ static long kvm_dev_ioctl_check_extension_generic(long arg) case KVM_CAP_USER_MEMORY: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: return 1; +#ifdef CONFIG_HAVE_KVM_IRQCHIP + case KVM_CAP_IRQ_ROUTING: + return 1; +#endif default: break; }