diff options
Diffstat (limited to 'drivers/xen/events.c')
| -rw-r--r-- | drivers/xen/events.c | 95 |
1 files changed, 84 insertions, 11 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c index db8f506817f0..5e1f34892dcc 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -29,6 +29,7 @@ #include <linux/bootmem.h> #include <linux/slab.h> +#include <asm/desc.h> #include <asm/ptrace.h> #include <asm/irq.h> #include <asm/idle.h> @@ -36,10 +37,14 @@ #include <asm/xen/hypercall.h> #include <asm/xen/hypervisor.h> +#include <xen/xen.h> +#include <xen/hvm.h> #include <xen/xen-ops.h> #include <xen/events.h> #include <xen/interface/xen.h> #include <xen/interface/event_channel.h> +#include <xen/interface/hvm/hvm_op.h> +#include <xen/interface/hvm/params.h> /* * This lock protects updates to the following mapping and reference-count @@ -335,9 +340,18 @@ static int find_unbound_irq(void) int irq; struct irq_desc *desc; - for (irq = 0; irq < nr_irqs; irq++) + for (irq = 0; irq < nr_irqs; irq++) { + desc = irq_to_desc(irq); + /* only 0->15 have init'd desc; handle irq > 16 */ + if (desc == NULL) + break; + if (desc->chip == &no_irq_chip) + break; + if (desc->chip != &xen_dynamic_chip) + continue; if (irq_info[irq].type == IRQT_UNBOUND) break; + } if (irq == nr_irqs) panic("No available IRQ to bind to: increase nr_irqs!\n"); @@ -346,7 +360,7 @@ static int find_unbound_irq(void) if (WARN_ON(desc == NULL)) return -1; - dynamic_irq_init(irq); + dynamic_irq_init_keep_chip_data(irq); return irq; } @@ -617,17 +631,13 @@ 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; @@ -664,14 +674,31 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) count = __get_cpu_var(xed_nesting_count); __get_cpu_var(xed_nesting_count) = 0; - } while(count != 1); + } while (count != 1 || vcpu_info->evtchn_upcall_pending); 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(); } +EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall); /* Rebind a new event channel to an existing irq. */ void rebind_evtchn_irq(int evtchn, int irq) @@ -708,7 +735,10 @@ static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu) struct evtchn_bind_vcpu bind_vcpu; int evtchn = evtchn_from_irq(irq); - if (!VALID_EVTCHN(evtchn)) + /* events delivered via platform PCI interrupts are always + * routed to vcpu 0 */ + if (!VALID_EVTCHN(evtchn) || + (xen_hvm_domain() && !xen_have_vector_callback)) return -1; /* Send future instances of this interrupt to other vcpu. */ @@ -933,6 +963,44 @@ 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); + +#ifdef CONFIG_XEN_PVHVM +/* 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); + } +} +#else +void xen_callback_vector(void) {} +#endif + void __init xen_init_IRQ(void) { int i; @@ -947,5 +1015,10 @@ 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()); + } } |
