diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h index 8767d99c4f64d9a7fc70a17d338ffe4770a5e969..e2ca3009255706910d1ddc407232f4d09f011f24 100644 --- a/arch/x86/include/asm/irq_vectors.h +++ b/arch/x86/include/asm/irq_vectors.h @@ -125,6 +125,9 @@ */ #define MCE_SELF_VECTOR 0xeb +/* Xen vector callback to receive events in a HVM domain */ +#define XEN_HVM_EVTCHN_CALLBACK 0xe9 + #define NR_VECTORS 256 #define FPU_IRQ 13 diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index cd49141cf153fb124dc46a6497dbc863a3c81ad9..6b196834a0dd909c5988267ca516b793c6691316 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1166,6 +1166,9 @@ ENTRY(xen_failsafe_callback) .previous ENDPROC(xen_failsafe_callback) +BUILD_INTERRUPT3(xen_hvm_callback_vector, XEN_HVM_EVTCHN_CALLBACK, + xen_evtchn_do_upcall) + #endif /* CONFIG_XEN */ #ifdef CONFIG_FUNCTION_TRACER diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 0697ff139837644f170f032ae525d9e112c71681..490ae2bb18a854d568496dd054bd6ec715ce02bf 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1329,6 +1329,9 @@ ENTRY(xen_failsafe_callback) CFI_ENDPROC END(xen_failsafe_callback) +apicinterrupt XEN_HVM_EVTCHN_CALLBACK \ + xen_hvm_callback_vector xen_evtchn_do_upcall + #endif /* CONFIG_XEN */ /* diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 09b36e9d507a27faef564956802a55141558bae8..b211a04c4b2ccbb6f1ad2c4b2388592532dff2f0 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -11,6 +11,7 @@ * Jeremy Fitzhardinge , XenSource Inc, 2007 */ +#include #include #include #include @@ -38,6 +39,7 @@ #include #include #include +#include #include #include @@ -80,6 +82,8 @@ struct shared_info xen_dummy_shared_info; void *xen_initial_gdt; RESERVE_BRK(shared_info_page_brk, PAGE_SIZE); +__read_mostly int xen_have_vector_callback; +EXPORT_SYMBOL_GPL(xen_have_vector_callback); /* * Point at some empty memory to start with. We map the real shared_info @@ -1277,6 +1281,24 @@ static void __init init_shared_info(void) per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; } +static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + int cpu = (long)hcpu; + switch (action) { + case CPU_UP_PREPARE: + per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = { + .notifier_call = xen_hvm_cpu_notify, +}; + static void __init xen_hvm_guest_init(void) { int r; @@ -1287,6 +1309,12 @@ static void __init xen_hvm_guest_init(void) return; init_shared_info(); + + if (xen_feature(XENFEAT_hvm_callback_vector)) + xen_have_vector_callback = 1; + register_cpu_notifier(&xen_hvm_cpu_notifier); + have_vcpu_info_placement = 0; + x86_init.irqs.intr_init = xen_init_IRQ; } static bool __init xen_hvm_platform(void) diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index f9153a300bcee998e1f78f95a202cc9036df79ca..0d0e0e6a747991f9904d78dc3b3fb91ec26992b1 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -38,6 +38,8 @@ void xen_enable_sysenter(void); void xen_enable_syscall(void); void xen_vcpu_restore(void); +void xen_callback_vector(void); + void __init xen_build_dynamic_phys_to_machine(void); void xen_init_irq_ops(void); diff --git a/drivers/xen/events.c b/drivers/xen/events.c index db8f506817f0ad30f2b54bde0ff778a7405ba59b..d659480125f07885164353c75b83a1174049b897 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -29,6 +29,7 @@ #include #include +#include #include #include #include @@ -36,10 +37,14 @@ #include #include +#include +#include #include #include #include #include +#include +#include /* * This lock protects updates to the following mapping and reference-count @@ -617,17 +622,13 @@ static DEFINE_PER_CPU(unsigned, xed_nesting_count); * a bitset of words which contain pending event bits. The second * level is a bitset of pending events themselves. */ -void xen_evtchn_do_upcall(struct pt_regs *regs) +static void __xen_evtchn_do_upcall(void) { int cpu = get_cpu(); - struct pt_regs *old_regs = set_irq_regs(regs); struct shared_info *s = HYPERVISOR_shared_info; struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu); unsigned count; - exit_idle(); - irq_enter(); - do { unsigned long pending_words; @@ -667,10 +668,26 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) } while(count != 1); out: + + put_cpu(); +} + +void xen_evtchn_do_upcall(struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + exit_idle(); + irq_enter(); + + __xen_evtchn_do_upcall(); + irq_exit(); set_irq_regs(old_regs); +} - put_cpu(); +void xen_hvm_evtchn_do_upcall(void) +{ + __xen_evtchn_do_upcall(); } /* Rebind a new event channel to an existing irq. */ @@ -933,6 +950,40 @@ static struct irq_chip xen_dynamic_chip __read_mostly = { .retrigger = retrigger_dynirq, }; +int xen_set_callback_via(uint64_t via) +{ + struct xen_hvm_param a; + a.domid = DOMID_SELF; + a.index = HVM_PARAM_CALLBACK_IRQ; + a.value = via; + return HYPERVISOR_hvm_op(HVMOP_set_param, &a); +} +EXPORT_SYMBOL_GPL(xen_set_callback_via); + +/* Vector callbacks are better than PCI interrupts to receive event + * channel notifications because we can receive vector callbacks on any + * vcpu and we don't need PCI support or APIC interactions. */ +void xen_callback_vector(void) +{ + int rc; + uint64_t callback_via; + if (xen_have_vector_callback) { + callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK); + rc = xen_set_callback_via(callback_via); + if (rc) { + printk(KERN_ERR "Request for Xen HVM callback vector" + " failed.\n"); + xen_have_vector_callback = 0; + return; + } + printk(KERN_INFO "Xen HVM callback vector for event delivery is " + "enabled\n"); + /* in the restore case the vector has already been allocated */ + if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors)) + alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector); + } +} + void __init xen_init_IRQ(void) { int i; @@ -947,5 +998,10 @@ void __init xen_init_IRQ(void) for (i = 0; i < NR_EVENT_CHANNELS; i++) mask_evtchn(i); - irq_ctx_init(smp_processor_id()); + if (xen_hvm_domain()) { + xen_callback_vector(); + native_init_IRQ(); + } else { + irq_ctx_init(smp_processor_id()); + } } diff --git a/include/xen/events.h b/include/xen/events.h index e68d59a90ca88b73c21b431c3cf538165916d5a7..a15d93262e308706eb4f3fe6a1283d0583f2b043 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -56,4 +56,11 @@ void xen_poll_irq(int irq); /* Determine the IRQ which is bound to an event channel */ unsigned irq_from_evtchn(unsigned int evtchn); +/* Xen HVM evtchn vector callback */ +extern void xen_hvm_callback_vector(void); +extern int xen_have_vector_callback; +int xen_set_callback_via(uint64_t via); +void xen_evtchn_do_upcall(struct pt_regs *regs); +void xen_hvm_evtchn_do_upcall(void); + #endif /* _XEN_EVENTS_H */ diff --git a/include/xen/hvm.h b/include/xen/hvm.h index 5dfe8fb86e6735df3b75370f8715ac321d2cafac..b193fa2f9fddb2ef6670a7e1aa7f27ef4b60edbe 100644 --- a/include/xen/hvm.h +++ b/include/xen/hvm.h @@ -3,6 +3,7 @@ #define XEN_HVM_H__ #include +#include static inline int hvm_get_parameter(int idx, uint64_t *value) { @@ -21,4 +22,9 @@ static inline int hvm_get_parameter(int idx, uint64_t *value) return r; } +#define HVM_CALLBACK_VIA_TYPE_VECTOR 0x2 +#define HVM_CALLBACK_VIA_TYPE_SHIFT 56 +#define HVM_CALLBACK_VECTOR(x) (((uint64_t)HVM_CALLBACK_VIA_TYPE_VECTOR)<<\ + HVM_CALLBACK_VIA_TYPE_SHIFT | (x)) + #endif /* XEN_HVM_H__ */ diff --git a/include/xen/interface/features.h b/include/xen/interface/features.h index f51b6413b05469abab7724717b465f7277137612..8ab08b91bf6f99f8580be7f15ba23dc6006c1c55 100644 --- a/include/xen/interface/features.h +++ b/include/xen/interface/features.h @@ -41,6 +41,9 @@ /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */ #define XENFEAT_mmu_pt_update_preserve_ad 5 +/* x86: Does this Xen host support the HVM callback vector type? */ +#define XENFEAT_hvm_callback_vector 8 + #define XENFEAT_NR_SUBMAPS 1 #endif /* __XEN_PUBLIC_FEATURES_H__ */