diff options
Diffstat (limited to 'drivers/xen/events.c')
| -rw-r--r-- | drivers/xen/events.c | 1605 |
1 files changed, 0 insertions, 1605 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c deleted file mode 100644 index 74681478100..00000000000 --- a/drivers/xen/events.c +++ /dev/null @@ -1,1605 +0,0 @@ -/* - * Xen event channels - * - * Xen models interrupts with abstract event channels. Because each - * domain gets 1024 event channels, but NR_IRQ is not that large, we - * must dynamically map irqs<->event channels. The event channels - * interface with the rest of the kernel by defining a xen interrupt - * chip. When an event is recieved, it is mapped to an irq and sent - * through the normal interrupt processing path. - * - * There are four kinds of events which can be mapped to an event - * channel: - * - * 1. Inter-domain notifications. This includes all the virtual - * device events, since they're driven by front-ends in another domain - * (typically dom0). - * 2. VIRQs, typically used for timers. These are per-cpu events. - * 3. IPIs. - * 4. PIRQs - Hardware interrupts. - * - * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 - */ - -#include <linux/linkage.h> -#include <linux/interrupt.h> -#include <linux/irq.h> -#include <linux/module.h> -#include <linux/string.h> -#include <linux/bootmem.h> -#include <linux/slab.h> -#include <linux/irqnr.h> -#include <linux/pci.h> - -#include <asm/desc.h> -#include <asm/ptrace.h> -#include <asm/irq.h> -#include <asm/idle.h> -#include <asm/io_apic.h> -#include <asm/sync_bitops.h> -#include <asm/xen/pci.h> -#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 - * arrays. The lock does not need to be acquired to read the mapping tables. - */ -static DEFINE_SPINLOCK(irq_mapping_update_lock); - -/* IRQ <-> VIRQ mapping. */ -static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1}; - -/* IRQ <-> IPI mapping */ -static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1}; - -/* Interrupt types. */ -enum xen_irq_type { - IRQT_UNBOUND = 0, - IRQT_PIRQ, - IRQT_VIRQ, - IRQT_IPI, - IRQT_EVTCHN -}; - -/* - * Packed IRQ information: - * type - enum xen_irq_type - * event channel - irq->event channel mapping - * cpu - cpu this event channel is bound to - * index - type-specific information: - * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM - * guest, or GSI (real passthrough IRQ) of the device. - * VIRQ - virq number - * IPI - IPI vector - * EVTCHN - - */ -struct irq_info -{ - enum xen_irq_type type; /* type */ - unsigned short evtchn; /* event channel */ - unsigned short cpu; /* cpu bound */ - - union { - unsigned short virq; - enum ipi_vector ipi; - struct { - unsigned short pirq; - unsigned short gsi; - unsigned char vector; - unsigned char flags; - } pirq; - } u; -}; -#define PIRQ_NEEDS_EOI (1 << 0) -#define PIRQ_SHAREABLE (1 << 1) - -static struct irq_info *irq_info; -static int *pirq_to_irq; - -static int *evtchn_to_irq; -struct cpu_evtchn_s { - unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG]; -}; - -static __initdata struct cpu_evtchn_s init_evtchn_mask = { - .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul, -}; -static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask; - -static inline unsigned long *cpu_evtchn_mask(int cpu) -{ - return cpu_evtchn_mask_p[cpu].bits; -} - -/* Xen will never allocate port zero for any purpose. */ -#define VALID_EVTCHN(chn) ((chn) != 0) - -static struct irq_chip xen_dynamic_chip; -static struct irq_chip xen_percpu_chip; -static struct irq_chip xen_pirq_chip; - -/* Constructor for packed IRQ information. */ -static struct irq_info mk_unbound_info(void) -{ - return (struct irq_info) { .type = IRQT_UNBOUND }; -} - -static struct irq_info mk_evtchn_info(unsigned short evtchn) -{ - return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn, - .cpu = 0 }; -} - -static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi) -{ - return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn, - .cpu = 0, .u.ipi = ipi }; -} - -static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq) -{ - return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn, - .cpu = 0, .u.virq = virq }; -} - -static struct irq_info mk_pirq_info(unsigned short evtchn, unsigned short pirq, - unsigned short gsi, unsigned short vector) -{ - return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn, - .cpu = 0, - .u.pirq = { .pirq = pirq, .gsi = gsi, .vector = vector } }; -} - -/* - * Accessors for packed IRQ information. - */ -static struct irq_info *info_for_irq(unsigned irq) -{ - return &irq_info[irq]; -} - -static unsigned int evtchn_from_irq(unsigned irq) -{ - if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq))) - return 0; - - return info_for_irq(irq)->evtchn; -} - -unsigned irq_from_evtchn(unsigned int evtchn) -{ - return evtchn_to_irq[evtchn]; -} -EXPORT_SYMBOL_GPL(irq_from_evtchn); - -static enum ipi_vector ipi_from_irq(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info == NULL); - BUG_ON(info->type != IRQT_IPI); - - return info->u.ipi; -} - -static unsigned virq_from_irq(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info == NULL); - BUG_ON(info->type != IRQT_VIRQ); - - return info->u.virq; -} - -static unsigned pirq_from_irq(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info == NULL); - BUG_ON(info->type != IRQT_PIRQ); - - return info->u.pirq.pirq; -} - -static unsigned gsi_from_irq(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info == NULL); - BUG_ON(info->type != IRQT_PIRQ); - - return info->u.pirq.gsi; -} - -static unsigned vector_from_irq(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info == NULL); - BUG_ON(info->type != IRQT_PIRQ); - - return info->u.pirq.vector; -} - -static enum xen_irq_type type_from_irq(unsigned irq) -{ - return info_for_irq(irq)->type; -} - -static unsigned cpu_from_irq(unsigned irq) -{ - return info_for_irq(irq)->cpu; -} - -static unsigned int cpu_from_evtchn(unsigned int evtchn) -{ - int irq = evtchn_to_irq[evtchn]; - unsigned ret = 0; - - if (irq != -1) - ret = cpu_from_irq(irq); - - return ret; -} - -static bool pirq_needs_eoi(unsigned irq) -{ - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info->type != IRQT_PIRQ); - - return info->u.pirq.flags & PIRQ_NEEDS_EOI; -} - -static inline unsigned long active_evtchns(unsigned int cpu, - struct shared_info *sh, - unsigned int idx) -{ - return (sh->evtchn_pending[idx] & - cpu_evtchn_mask(cpu)[idx] & - ~sh->evtchn_mask[idx]); -} - -static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu) -{ - int irq = evtchn_to_irq[chn]; - - BUG_ON(irq == -1); -#ifdef CONFIG_SMP - cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu)); -#endif - - clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq))); - set_bit(chn, cpu_evtchn_mask(cpu)); - - irq_info[irq].cpu = cpu; -} - -static void init_evtchn_cpu_bindings(void) -{ - int i; -#ifdef CONFIG_SMP - struct irq_desc *desc; - - /* By default all event channels notify CPU#0. */ - for_each_irq_desc(i, desc) { - cpumask_copy(desc->affinity, cpumask_of(0)); - } -#endif - - for_each_possible_cpu(i) - memset(cpu_evtchn_mask(i), - (i == 0) ? ~0 : 0, sizeof(struct cpu_evtchn_s)); - -} - -static inline void clear_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_clear_bit(port, &s->evtchn_pending[0]); -} - -static inline void set_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_set_bit(port, &s->evtchn_pending[0]); -} - -static inline int test_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - return sync_test_bit(port, &s->evtchn_pending[0]); -} - - -/** - * notify_remote_via_irq - send event to remote end of event channel via irq - * @irq: irq of event channel to send event to - * - * Unlike notify_remote_via_evtchn(), this is safe to use across - * save/restore. Notifications on a broken connection are silently - * dropped. - */ -void notify_remote_via_irq(int irq) -{ - int evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) - notify_remote_via_evtchn(evtchn); -} -EXPORT_SYMBOL_GPL(notify_remote_via_irq); - -static void mask_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_set_bit(port, &s->evtchn_mask[0]); -} - -static void unmask_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - unsigned int cpu = get_cpu(); - - BUG_ON(!irqs_disabled()); - - /* Slow path (hypercall) if this is a non-local port. */ - if (unlikely(cpu != cpu_from_evtchn(port))) { - struct evtchn_unmask unmask = { .port = port }; - (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask); - } else { - struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); - - sync_clear_bit(port, &s->evtchn_mask[0]); - - /* - * The following is basically the equivalent of - * 'hw_resend_irq'. Just like a real IO-APIC we 'lose - * the interrupt edge' if the channel is masked. - */ - if (sync_test_bit(port, &s->evtchn_pending[0]) && - !sync_test_and_set_bit(port / BITS_PER_LONG, - &vcpu_info->evtchn_pending_sel)) - vcpu_info->evtchn_upcall_pending = 1; - } - - put_cpu(); -} - -static int get_nr_hw_irqs(void) -{ - int ret = 1; - -#ifdef CONFIG_X86_IO_APIC - ret = get_nr_irqs_gsi(); -#endif - - return ret; -} - -static int find_unbound_pirq(int type) -{ - int rc, i; - struct physdev_get_free_pirq op_get_free_pirq; - op_get_free_pirq.type = type; - - rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq); - if (!rc) - return op_get_free_pirq.pirq; - - for (i = 0; i < nr_irqs; i++) { - if (pirq_to_irq[i] < 0) - return i; - } - return -1; -} - -static int find_unbound_irq(void) -{ - struct irq_data *data; - int irq, res; - int bottom = get_nr_hw_irqs(); - int top = nr_irqs-1; - - if (bottom == nr_irqs) - goto no_irqs; - - /* This loop starts from the top of IRQ space and goes down. - * We need this b/c if we have a PCI device in a Xen PV guest - * we do not have an IO-APIC (though the backend might have them) - * mapped in. To not have a collision of physical IRQs with the Xen - * event channels start at the top of the IRQ space for virtual IRQs. - */ - for (irq = top; irq > bottom; irq--) { - data = irq_get_irq_data(irq); - /* only 15->0 have init'd desc; handle irq > 16 */ - if (!data) - break; - if (data->chip == &no_irq_chip) - break; - if (data->chip != &xen_dynamic_chip) - continue; - if (irq_info[irq].type == IRQT_UNBOUND) - return irq; - } - - if (irq == bottom) - goto no_irqs; - - res = irq_alloc_desc_at(irq, -1); - - if (WARN_ON(res != irq)) - return -1; - - return irq; - -no_irqs: - panic("No available IRQ to bind to: increase nr_irqs!\n"); -} - -static bool identity_mapped_irq(unsigned irq) -{ - /* identity map all the hardware irqs */ - return irq < get_nr_hw_irqs(); -} - -static void pirq_unmask_notify(int irq) -{ - struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) }; - - if (unlikely(pirq_needs_eoi(irq))) { - int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi); - WARN_ON(rc); - } -} - -static void pirq_query_unmask(int irq) -{ - struct physdev_irq_status_query irq_status; - struct irq_info *info = info_for_irq(irq); - - BUG_ON(info->type != IRQT_PIRQ); - - irq_status.irq = pirq_from_irq(irq); - if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status)) - irq_status.flags = 0; - - info->u.pirq.flags &= ~PIRQ_NEEDS_EOI; - if (irq_status.flags & XENIRQSTAT_needs_eoi) - info->u.pirq.flags |= PIRQ_NEEDS_EOI; -} - -static bool probing_irq(int irq) -{ - struct irq_desc *desc = irq_to_desc(irq); - - return desc && desc->action == NULL; -} - -static unsigned int startup_pirq(unsigned int irq) -{ - struct evtchn_bind_pirq bind_pirq; - struct irq_info *info = info_for_irq(irq); - int evtchn = evtchn_from_irq(irq); - int rc; - - BUG_ON(info->type != IRQT_PIRQ); - - if (VALID_EVTCHN(evtchn)) - goto out; - - bind_pirq.pirq = pirq_from_irq(irq); - /* NB. We are happy to share unless we are probing. */ - bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ? - BIND_PIRQ__WILL_SHARE : 0; - rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq); - if (rc != 0) { - if (!probing_irq(irq)) - printk(KERN_INFO "Failed to obtain physical IRQ %d\n", - irq); - return 0; - } - evtchn = bind_pirq.port; - - pirq_query_unmask(irq); - - evtchn_to_irq[evtchn] = irq; - bind_evtchn_to_cpu(evtchn, 0); - info->evtchn = evtchn; - -out: - unmask_evtchn(evtchn); - pirq_unmask_notify(irq); - - return 0; -} - -static void shutdown_pirq(unsigned int irq) -{ - struct evtchn_close close; - struct irq_info *info = info_for_irq(irq); - int evtchn = evtchn_from_irq(irq); - - BUG_ON(info->type != IRQT_PIRQ); - - if (!VALID_EVTCHN(evtchn)) - return; - - mask_evtchn(evtchn); - - close.port = evtchn; - if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) - BUG(); - - bind_evtchn_to_cpu(evtchn, 0); - evtchn_to_irq[evtchn] = -1; - info->evtchn = 0; -} - -static void enable_pirq(unsigned int irq) -{ - startup_pirq(irq); -} - -static void disable_pirq(unsigned int irq) -{ -} - -static void ack_pirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - - move_native_irq(irq); - - if (VALID_EVTCHN(evtchn)) { - mask_evtchn(evtchn); - clear_evtchn(evtchn); - } -} - -static void end_pirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - struct irq_desc *desc = irq_to_desc(irq); - - if (WARN_ON(!desc)) - return; - - if ((desc->status & (IRQ_DISABLED|IRQ_PENDING)) == - (IRQ_DISABLED|IRQ_PENDING)) { - shutdown_pirq(irq); - } else if (VALID_EVTCHN(evtchn)) { - unmask_evtchn(evtchn); - pirq_unmask_notify(irq); - } -} - -static int find_irq_by_gsi(unsigned gsi) -{ - int irq; - - for (irq = 0; irq < nr_irqs; irq++) { - struct irq_info *info = info_for_irq(irq); - - if (info == NULL || info->type != IRQT_PIRQ) - continue; - - if (gsi_from_irq(irq) == gsi) - return irq; - } - - return -1; -} - -int xen_allocate_pirq(unsigned gsi, int shareable, char *name) -{ - return xen_map_pirq_gsi(gsi, gsi, shareable, name); -} - -/* xen_map_pirq_gsi might allocate irqs from the top down, as a - * consequence don't assume that the irq number returned has a low value - * or can be used as a pirq number unless you know otherwise. - * - * One notable exception is when xen_map_pirq_gsi is called passing an - * hardware gsi as argument, in that case the irq number returned - * matches the gsi number passed as second argument. - * - * Note: We don't assign an event channel until the irq actually started - * up. Return an existing irq if we've already got one for the gsi. - */ -int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name) -{ - int irq = 0; - struct physdev_irq irq_op; - - spin_lock(&irq_mapping_update_lock); - - if ((pirq > nr_irqs) || (gsi > nr_irqs)) { - printk(KERN_WARNING "xen_map_pirq_gsi: %s %s is incorrect!\n", - pirq > nr_irqs ? "pirq" :"", - gsi > nr_irqs ? "gsi" : ""); - goto out; - } - - irq = find_irq_by_gsi(gsi); - if (irq != -1) { - printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n", - irq, gsi); - goto out; /* XXX need refcount? */ - } - - /* If we are a PV guest, we don't have GSIs (no ACPI passed). Therefore - * we are using the !xen_initial_domain() to drop in the function.*/ - if (identity_mapped_irq(gsi) || (!xen_initial_domain() && - xen_pv_domain())) { - irq = gsi; - irq_alloc_desc_at(irq, -1); - } else - irq = find_unbound_irq(); - - set_irq_chip_and_handler_name(irq, &xen_pirq_chip, - handle_level_irq, name); - - irq_op.irq = irq; - irq_op.vector = 0; - - /* Only the privileged domain can do this. For non-priv, the pcifront - * driver provides a PCI bus that does the call to do exactly - * this in the priv domain. */ - if (xen_initial_domain() && - HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) { - irq_free_desc(irq); - irq = -ENOSPC; - goto out; - } - - irq_info[irq] = mk_pirq_info(0, pirq, gsi, irq_op.vector); - irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0; - pirq_to_irq[pirq] = irq; - -out: - spin_unlock(&irq_mapping_update_lock); - - return irq; -} - -#ifdef CONFIG_PCI_MSI -#include <linux/msi.h> -#include "../pci/msi.h" - -void xen_allocate_pirq_msi(char *name, int *irq, int *pirq, int alloc) -{ - spin_lock(&irq_mapping_update_lock); - - if (alloc & XEN_ALLOC_IRQ) { - *irq = find_unbound_irq(); - if (*irq == -1) - goto out; - } - - if (alloc & XEN_ALLOC_PIRQ) { - *pirq = find_unbound_pirq(MAP_PIRQ_TYPE_MSI); - if (*pirq == -1) - goto out; - } - - set_irq_chip_and_handler_name(*irq, &xen_pirq_chip, - handle_level_irq, name); - - irq_info[*irq] = mk_pirq_info(0, *pirq, 0, 0); - pirq_to_irq[*pirq] = *irq; - -out: - spin_unlock(&irq_mapping_update_lock); -} - -int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type) -{ - int irq = -1; - struct physdev_map_pirq map_irq; - int rc; - int pos; - u32 table_offset, bir; - - memset(&map_irq, 0, sizeof(map_irq)); - map_irq.domid = DOMID_SELF; - map_irq.type = MAP_PIRQ_TYPE_MSI; - map_irq.index = -1; - map_irq.pirq = -1; - map_irq.bus = dev->bus->number; - map_irq.devfn = dev->devfn; - - if (type == PCI_CAP_ID_MSIX) { - pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); - - pci_read_config_dword(dev, msix_table_offset_reg(pos), - &table_offset); - bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK); - - map_irq.table_base = pci_resource_start(dev, bir); - map_irq.entry_nr = msidesc->msi_attrib.entry_nr; - } - - spin_lock(&irq_mapping_update_lock); - - irq = find_unbound_irq(); - - if (irq == -1) - goto out; - - rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); - if (rc) { - printk(KERN_WARNING "xen map irq failed %d\n", rc); - - irq_free_desc(irq); - - irq = -1; - goto out; - } - irq_info[irq] = mk_pirq_info(0, map_irq.pirq, 0, map_irq.index); - - set_irq_chip_and_handler_name(irq, &xen_pirq_chip, - handle_level_irq, - (type == PCI_CAP_ID_MSIX) ? "msi-x":"msi"); - -out: - spin_unlock(&irq_mapping_update_lock); - return irq; -} -#endif - -int xen_destroy_irq(int irq) -{ - struct irq_desc *desc; - struct physdev_unmap_pirq unmap_irq; - struct irq_info *info = info_for_irq(irq); - int rc = -ENOENT; - - spin_lock(&irq_mapping_update_lock); - - desc = irq_to_desc(irq); - if (!desc) - goto out; - - if (xen_initial_domain()) { - unmap_irq.pirq = info->u.pirq.pirq; - unmap_irq.domid = DOMID_SELF; - rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq); - if (rc) { - printk(KERN_WARNING "unmap irq failed %d\n", rc); - goto out; - } - pirq_to_irq[info->u.pirq.pirq] = -1; - } - irq_info[irq] = mk_unbound_info(); - - irq_free_desc(irq); - -out: - spin_unlock(&irq_mapping_update_lock); - return rc; -} - -int xen_vector_from_irq(unsigned irq) -{ - return vector_from_irq(irq); -} - -int xen_gsi_from_irq(unsigned irq) -{ - return gsi_from_irq(irq); -} - -int xen_irq_from_pirq(unsigned pirq) -{ - return pirq_to_irq[pirq]; -} - -int bind_evtchn_to_irq(unsigned int evtchn) -{ - int irq; - - spin_lock(&irq_mapping_update_lock); - - irq = evtchn_to_irq[evtchn]; - - if (irq == -1) { - irq = find_unbound_irq(); - - set_irq_chip_and_handler_name(irq, &xen_dynamic_chip, - handle_fasteoi_irq, "event"); - - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_evtchn_info(evtchn); - } - - spin_unlock(&irq_mapping_update_lock); - - return irq; -} -EXPORT_SYMBOL_GPL(bind_evtchn_to_irq); - -static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) -{ - struct evtchn_bind_ipi bind_ipi; - int evtchn, irq; - - spin_lock(&irq_mapping_update_lock); - - irq = per_cpu(ipi_to_irq, cpu)[ipi]; - - if (irq == -1) { - irq = find_unbound_irq(); - if (irq < 0) - goto out; - - set_irq_chip_and_handler_name(irq, &xen_percpu_chip, - handle_percpu_irq, "ipi"); - - bind_ipi.vcpu = cpu; - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, - &bind_ipi) != 0) - BUG(); - evtchn = bind_ipi.port; - - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_ipi_info(evtchn, ipi); - per_cpu(ipi_to_irq, cpu)[ipi] = irq; - - bind_evtchn_to_cpu(evtchn, cpu); - } - - out: - spin_unlock(&irq_mapping_update_lock); - return irq; -} - - -int bind_virq_to_irq(unsigned int virq, unsigned int cpu) -{ - struct evtchn_bind_virq bind_virq; - int evtchn, irq; - - spin_lock(&irq_mapping_update_lock); - - irq = per_cpu(virq_to_irq, cpu)[virq]; - - if (irq == -1) { - irq = find_unbound_irq(); - - set_irq_chip_and_handler_name(irq, &xen_percpu_chip, - handle_percpu_irq, "virq"); - - bind_virq.virq = virq; - bind_virq.vcpu = cpu; - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, - &bind_virq) != 0) - BUG(); - evtchn = bind_virq.port; - - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_virq_info(evtchn, virq); - - per_cpu(virq_to_irq, cpu)[virq] = irq; - - bind_evtchn_to_cpu(evtchn, cpu); - } - - spin_unlock(&irq_mapping_update_lock); - - return irq; -} - -static void unbind_from_irq(unsigned int irq) -{ - struct evtchn_close close; - int evtchn = evtchn_from_irq(irq); - - spin_lock(&irq_mapping_update_lock); - - if (VALID_EVTCHN(evtchn)) { - close.port = evtchn; - if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) - BUG(); - - switch (type_from_irq(irq)) { - case IRQT_VIRQ: - per_cpu(virq_to_irq, cpu_from_evtchn(evtchn)) - [virq_from_irq(irq)] = -1; - break; - case IRQT_IPI: - per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn)) - [ipi_from_irq(irq)] = -1; - break; - default: - break; - } - - /* Closed ports are implicitly re-bound to VCPU0. */ - bind_evtchn_to_cpu(evtchn, 0); - - evtchn_to_irq[evtchn] = -1; - } - - if (irq_info[irq].type != IRQT_UNBOUND) { - irq_info[irq] = mk_unbound_info(); - - irq_free_desc(irq); - } - - spin_unlock(&irq_mapping_update_lock); -} - -int bind_evtchn_to_irqhandler(unsigned int evtchn, - irq_handler_t handler, - unsigned long irqflags, - const char *devname, void *dev_id) -{ - unsigned int irq; - int retval; - - irq = bind_evtchn_to_irq(evtchn); - retval = request_irq(irq, handler, irqflags, devname, dev_id); - if (retval != 0) { - unbind_from_irq(irq); - return retval; - } - - return irq; -} -EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler); - -int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, - irq_handler_t handler, - unsigned long irqflags, const char *devname, void *dev_id) -{ - unsigned int irq; - int retval; - - irq = bind_virq_to_irq(virq, cpu); - retval = request_irq(irq, handler, irqflags, devname, dev_id); - if (retval != 0) { - unbind_from_irq(irq); - return retval; - } - - return irq; -} -EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler); - -int bind_ipi_to_irqhandler(enum ipi_vector ipi, - unsigned int cpu, - irq_handler_t handler, - unsigned long irqflags, - const char *devname, - void *dev_id) -{ - int irq, retval; - - irq = bind_ipi_to_irq(ipi, cpu); - if (irq < 0) - return irq; - - irqflags |= IRQF_NO_SUSPEND; - retval = request_irq(irq, handler, irqflags, devname, dev_id); - if (retval != 0) { - unbind_from_irq(irq); - return retval; - } - - return irq; -} - -void unbind_from_irqhandler(unsigned int irq, void *dev_id) -{ - free_irq(irq, dev_id); - unbind_from_irq(irq); -} -EXPORT_SYMBOL_GPL(unbind_from_irqhandler); - -void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector) -{ - int irq = per_cpu(ipi_to_irq, cpu)[vector]; - BUG_ON(irq < 0); - notify_remote_via_irq(irq); -} - -irqreturn_t xen_debug_interrupt(int irq, void *dev_id) -{ - struct shared_info *sh = HYPERVISOR_shared_info; - int cpu = smp_processor_id(); - unsigned long *cpu_evtchn = cpu_evtchn_mask(cpu); - int i; - unsigned long flags; - static DEFINE_SPINLOCK(debug_lock); - struct vcpu_info *v; - - spin_lock_irqsave(&debug_lock, flags); - - printk("\nvcpu %d\n ", cpu); - - for_each_online_cpu(i) { - int pending; - v = per_cpu(xen_vcpu, i); - pending = (get_irq_regs() && i == cpu) - ? xen_irqs_disabled(get_irq_regs()) - : v->evtchn_upcall_mask; - printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i, - pending, v->evtchn_upcall_pending, - (int)(sizeof(v->evtchn_pending_sel)*2), - v->evtchn_pending_sel); - } - v = per_cpu(xen_vcpu, cpu); - - printk("\npending:\n "); - for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--) - printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2, - sh->evtchn_pending[i], - i % 8 == 0 ? "\n " : " "); - printk("\nglobal mask:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) - printk("%0*lx%s", - (int)(sizeof(sh->evtchn_mask[0])*2), - sh->evtchn_mask[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nglobally unmasked:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) - printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2), - sh->evtchn_pending[i] & ~sh->evtchn_mask[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nlocal cpu%d mask:\n ", cpu); - for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--) - printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2), - cpu_evtchn[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nlocally unmasked:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) { - unsigned long pending = sh->evtchn_pending[i] - & ~sh->evtchn_mask[i] - & cpu_evtchn[i]; - printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2), - pending, i % 8 == 0 ? "\n " : " "); - } - - printk("\npending list:\n"); - for (i = 0; i < NR_EVENT_CHANNELS; i++) { - if (sync_test_bit(i, sh->evtchn_pending)) { - int word_idx = i / BITS_PER_LONG; - printk(" %d: event %d -> irq %d%s%s%s\n", - cpu_from_evtchn(i), i, - evtchn_to_irq[i], - sync_test_bit(word_idx, &v->evtchn_pending_sel) - ? "" : " l2-clear", - !sync_test_bit(i, sh->evtchn_mask) - ? "" : " globally-masked", - sync_test_bit(i, cpu_evtchn) - ? "" : " locally-masked"); - } - } - - spin_unlock_irqrestore(&debug_lock, flags); - - return IRQ_HANDLED; -} - -static DEFINE_PER_CPU(unsigned, xed_nesting_count); - -/* - * Search the CPUs pending events bitmasks. For each one found, map - * the event number to an irq, and feed it into do_IRQ() for - * handling. - * - * Xen uses a two-level bitmap to speed searching. The first level is - * a bitset of words which contain pending event bits. The second - * level is a bitset of pending events themselves. - */ -static void __xen_evtchn_do_upcall(void) -{ - int cpu = get_cpu(); - struct shared_info *s = HYPERVISOR_shared_info; - struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); - unsigned count; - - do { - unsigned long pending_words; - - vcpu_info->evtchn_upcall_pending = 0; - - if (__this_cpu_inc_return(xed_nesting_count) - 1) - goto out; - -#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */ - /* Clear master flag /before/ clearing selector flag. */ - wmb(); -#endif - pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0); - while (pending_words != 0) { - unsigned long pending_bits; - int word_idx = __ffs(pending_words); - pending_words &= ~(1UL << word_idx); - - while ((pending_bits = active_evtchns(cpu, s, word_idx)) != 0) { - int bit_idx = __ffs(pending_bits); - int port = (word_idx * BITS_PER_LONG) + bit_idx; - int irq = evtchn_to_irq[port]; - struct irq_desc *desc; - - mask_evtchn(port); - clear_evtchn(port); - - if (irq != -1) { - desc = irq_to_desc(irq); - if (desc) - generic_handle_irq_desc(irq, desc); - } - } - } - - BUG_ON(!irqs_disabled()); - - count = __this_cpu_read(xed_nesting_count); - __this_cpu_write(xed_nesting_count, 0); - } 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); -} - -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) -{ - struct irq_info *info = info_for_irq(irq); - - /* Make sure the irq is masked, since the new event channel - will also be masked. */ - disable_irq(irq); - - spin_lock(&irq_mapping_update_lock); - - /* After resume the irq<->evtchn mappings are all cleared out */ - BUG_ON(evtchn_to_irq[evtchn] != -1); - /* Expect irq to have been bound before, - so there should be a proper type */ - BUG_ON(info->type == IRQT_UNBOUND); - - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_evtchn_info(evtchn); - - spin_unlock(&irq_mapping_update_lock); - - /* new event channels are always bound to cpu 0 */ - irq_set_affinity(irq, cpumask_of(0)); - - /* Unmask the event channel. */ - enable_irq(irq); -} - -/* Rebind an evtchn so that it gets delivered to a specific cpu */ -static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu) -{ - struct evtchn_bind_vcpu bind_vcpu; - int evtchn = evtchn_from_irq(irq); - - /* 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. */ - bind_vcpu.port = evtchn; - bind_vcpu.vcpu = tcpu; - - /* - * If this fails, it usually just indicates that we're dealing with a - * virq or IPI channel, which don't actually need to be rebound. Ignore - * it, but don't do the xenlinux-level rebind in that case. - */ - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0) - bind_evtchn_to_cpu(evtchn, tcpu); - - return 0; -} - -static int set_affinity_irq(unsigned irq, const struct cpumask *dest) -{ - unsigned tcpu = cpumask_first(dest); - - return rebind_irq_to_cpu(irq, tcpu); -} - -int resend_irq_on_evtchn(unsigned int irq) -{ - int masked, evtchn = evtchn_from_irq(irq); - struct shared_info *s = HYPERVISOR_shared_info; - - if (!VALID_EVTCHN(evtchn)) - return 1; - - masked = sync_test_and_set_bit(evtchn, s->evtchn_mask); - sync_set_bit(evtchn, s->evtchn_pending); - if (!masked) - unmask_evtchn(evtchn); - - return 1; -} - -static void enable_dynirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) - unmask_evtchn(evtchn); -} - -static void disable_dynirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) - mask_evtchn(evtchn); -} - -static void ack_dynirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - - move_masked_irq(irq); - - if (VALID_EVTCHN(evtchn)) - unmask_evtchn(evtchn); -} - -static int retrigger_dynirq(unsigned int irq) -{ - int evtchn = evtchn_from_irq(irq); - struct shared_info *sh = HYPERVISOR_shared_info; - int ret = 0; - - if (VALID_EVTCHN(evtchn)) { - int masked; - - masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask); - sync_set_bit(evtchn, sh->evtchn_pending); - if (!masked) - unmask_evtchn(evtchn); - ret = 1; - } - - return ret; -} - -static void restore_cpu_pirqs(void) -{ - int pirq, rc, irq, gsi; - struct physdev_map_pirq map_irq; - - for (pirq = 0; pirq < nr_irqs; pirq++) { - irq = pirq_to_irq[pirq]; - if (irq == -1) - continue; - - /* save/restore of PT devices doesn't work, so at this point the - * only devices present are GSI based emulated devices */ - gsi = gsi_from_irq(irq); - if (!gsi) - continue; - - map_irq.domid = DOMID_SELF; - map_irq.type = MAP_PIRQ_TYPE_GSI; - map_irq.index = gsi; - map_irq.pirq = pirq; - - rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); - if (rc) { - printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n", - gsi, irq, pirq, rc); - irq_info[irq] = mk_unbound_info(); - pirq_to_irq[pirq] = -1; - continue; - } - - printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq); - - startup_pirq(irq); - } -} - -static void restore_cpu_virqs(unsigned int cpu) -{ - struct evtchn_bind_virq bind_virq; - int virq, irq, evtchn; - - for (virq = 0; virq < NR_VIRQS; virq++) { - if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1) - continue; - - BUG_ON(virq_from_irq(irq) != virq); - - /* Get a new binding from Xen. */ - bind_virq.virq = virq; - bind_virq.vcpu = cpu; - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, - &bind_virq) != 0) - BUG(); - evtchn = bind_virq.port; - - /* Record the new mapping. */ - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_virq_info(evtchn, virq); - bind_evtchn_to_cpu(evtchn, cpu); - } -} - -static void restore_cpu_ipis(unsigned int cpu) -{ - struct evtchn_bind_ipi bind_ipi; - int ipi, irq, evtchn; - - for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) { - if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1) - continue; - - BUG_ON(ipi_from_irq(irq) != ipi); - - /* Get a new binding from Xen. */ - bind_ipi.vcpu = cpu; - if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, - &bind_ipi) != 0) - BUG(); - evtchn = bind_ipi.port; - - /* Record the new mapping. */ - evtchn_to_irq[evtchn] = irq; - irq_info[irq] = mk_ipi_info(evtchn, ipi); - bind_evtchn_to_cpu(evtchn, cpu); - } -} - -/* Clear an irq's pending state, in preparation for polling on it */ -void xen_clear_irq_pending(int irq) -{ - int evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) - clear_evtchn(evtchn); -} -EXPORT_SYMBOL(xen_clear_irq_pending); -void xen_set_irq_pending(int irq) -{ - int evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) - set_evtchn(evtchn); -} - -bool xen_test_irq_pending(int irq) -{ - int evtchn = evtchn_from_irq(irq); - bool ret = false; - - if (VALID_EVTCHN(evtchn)) - ret = test_evtchn(evtchn); - - return ret; -} - -/* Poll waiting for an irq to become pending with timeout. In the usual case, - * the irq will be disabled so it won't deliver an interrupt. */ -void xen_poll_irq_timeout(int irq, u64 timeout) -{ - evtchn_port_t evtchn = evtchn_from_irq(irq); - - if (VALID_EVTCHN(evtchn)) { - struct sched_poll poll; - - poll.nr_ports = 1; - poll.timeout = timeout; - set_xen_guest_handle(poll.ports, &evtchn); - - if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0) - BUG(); - } -} -EXPORT_SYMBOL(xen_poll_irq_timeout); -/* Poll waiting for an irq to become pending. In the usual case, the - * irq will be disabled so it won't deliver an interrupt. */ -void xen_poll_irq(int irq) -{ - xen_poll_irq_timeout(irq, 0 /* no timeout */); -} - -void xen_irq_resume(void) -{ - unsigned int cpu, irq, evtchn; - struct irq_desc *desc; - - init_evtchn_cpu_bindings(); - - /* New event-channel space is not 'live' yet. */ - for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++) - mask_evtchn(evtchn); - - /* No IRQ <-> event-channel mappings. */ - for (irq = 0; irq < nr_irqs; irq++) - irq_info[irq].evtchn = 0; /* zap event-channel binding */ - - for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++) - evtchn_to_irq[evtchn] = -1; - - for_each_possible_cpu(cpu) { - restore_cpu_virqs(cpu); - restore_cpu_ipis(cpu); - } - - /* - * Unmask any IRQF_NO_SUSPEND IRQs which are enabled. These - * are not handled by the IRQ core. - */ - for_each_irq_desc(irq, desc) { - if (!desc->action || !(desc->action->flags & IRQF_NO_SUSPEND)) - continue; - if (desc->status & IRQ_DISABLED) - continue; - - evtchn = evtchn_from_irq(irq); - if (evtchn == -1) - continue; - - unmask_evtchn(evtchn); - } - - restore_cpu_pirqs(); -} - -static struct irq_chip xen_dynamic_chip __read_mostly = { - .name = "xen-dyn", - - .disable = disable_dynirq, - .mask = disable_dynirq, - .unmask = enable_dynirq, - - .eoi = ack_dynirq, - .set_affinity = set_affinity_irq, - .retrigger = retrigger_dynirq, -}; - -static struct irq_chip xen_pirq_chip __read_mostly = { - .name = "xen-pirq", - - .startup = startup_pirq, - .shutdown = shutdown_pirq, - - .enable = enable_pirq, - .unmask = enable_pirq, - - .disable = disable_pirq, - .mask = disable_pirq, - - .ack = ack_pirq, - .end = end_pirq, - - .set_affinity = set_affinity_irq, - - .retrigger = retrigger_dynirq, -}; - -static struct irq_chip xen_percpu_chip __read_mostly = { - .name = "xen-percpu", - - .disable = disable_dynirq, - .mask = disable_dynirq, - .unmask = enable_dynirq, - - .ack = ack_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; - - cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s), - GFP_KERNEL); - irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL); - - /* We are using nr_irqs as the maximum number of pirq available but - * that number is actually chosen by Xen and we don't know exactly - * what it is. Be careful choosing high pirq numbers. */ - pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL); - for (i = 0; i < nr_irqs; i++) - pirq_to_irq[i] = -1; - - evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq), - GFP_KERNEL); - for (i = 0; i < NR_EVENT_CHANNELS; i++) - evtchn_to_irq[i] = -1; - - init_evtchn_cpu_bindings(); - - /* No event channels are 'live' right now. */ - for (i = 0; i < NR_EVENT_CHANNELS; i++) - mask_evtchn(i); - - if (xen_hvm_domain()) { - xen_callback_vector(); - native_init_IRQ(); - /* pci_xen_hvm_init must be called after native_init_IRQ so that - * __acpi_register_gsi can point at the right function */ - pci_xen_hvm_init(); - } else { - irq_ctx_init(smp_processor_id()); - if (xen_initial_domain()) - xen_setup_pirqs(); - } -} |