| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * 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 received, 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 |
| */ |
| |
| #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt |
| |
| #include <linux/linkage.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/moduleparam.h> |
| #include <linux/string.h> |
| #include <linux/memblock.h> |
| #include <linux/slab.h> |
| #include <linux/irqnr.h> |
| #include <linux/pci.h> |
| #include <linux/spinlock.h> |
| #include <linux/cpuhotplug.h> |
| #include <linux/atomic.h> |
| #include <linux/ktime.h> |
| |
| #ifdef CONFIG_X86 |
| #include <asm/desc.h> |
| #include <asm/ptrace.h> |
| #include <asm/idtentry.h> |
| #include <asm/irq.h> |
| #include <asm/io_apic.h> |
| #include <asm/i8259.h> |
| #include <asm/xen/pci.h> |
| #endif |
| #include <asm/sync_bitops.h> |
| #include <asm/xen/hypercall.h> |
| #include <asm/xen/hypervisor.h> |
| #include <xen/page.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> |
| #include <xen/interface/physdev.h> |
| #include <xen/interface/sched.h> |
| #include <xen/interface/vcpu.h> |
| #include <asm/hw_irq.h> |
| |
| #include "events_internal.h" |
| |
| #undef MODULE_PARAM_PREFIX |
| #define MODULE_PARAM_PREFIX "xen." |
| |
| /* 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 { |
| struct list_head list; |
| struct list_head eoi_list; |
| short refcnt; |
| u8 spurious_cnt; |
| u8 is_accounted; |
| enum xen_irq_type type; /* type */ |
| unsigned irq; |
| evtchn_port_t evtchn; /* event channel */ |
| unsigned short cpu; /* cpu bound */ |
| unsigned short eoi_cpu; /* EOI must happen on this cpu-1 */ |
| unsigned int irq_epoch; /* If eoi_cpu valid: irq_epoch of event */ |
| u64 eoi_time; /* Time in jiffies when to EOI. */ |
| |
| union { |
| unsigned short virq; |
| enum ipi_vector ipi; |
| struct { |
| unsigned short pirq; |
| unsigned short gsi; |
| unsigned char vector; |
| unsigned char flags; |
| uint16_t domid; |
| } pirq; |
| } u; |
| }; |
| |
| #define PIRQ_NEEDS_EOI (1 << 0) |
| #define PIRQ_SHAREABLE (1 << 1) |
| #define PIRQ_MSI_GROUP (1 << 2) |
| |
| static uint __read_mostly event_loop_timeout = 2; |
| module_param(event_loop_timeout, uint, 0644); |
| |
| static uint __read_mostly event_eoi_delay = 10; |
| module_param(event_eoi_delay, uint, 0644); |
| |
| const struct evtchn_ops *evtchn_ops; |
| |
| /* |
| * 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_MUTEX(irq_mapping_update_lock); |
| |
| /* |
| * Lock protecting event handling loop against removing event channels. |
| * Adding of event channels is no issue as the associated IRQ becomes active |
| * only after everything is setup (before request_[threaded_]irq() the handler |
| * can't be entered for an event, as the event channel will be unmasked only |
| * then). |
| */ |
| static DEFINE_RWLOCK(evtchn_rwlock); |
| |
| /* |
| * Lock hierarchy: |
| * |
| * irq_mapping_update_lock |
| * evtchn_rwlock |
| * IRQ-desc lock |
| * percpu eoi_list_lock |
| */ |
| |
| static LIST_HEAD(xen_irq_list_head); |
| |
| /* 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}; |
| |
| /* Event channel distribution data */ |
| static atomic_t channels_on_cpu[NR_CPUS]; |
| |
| static int **evtchn_to_irq; |
| #ifdef CONFIG_X86 |
| static unsigned long *pirq_eoi_map; |
| #endif |
| static bool (*pirq_needs_eoi)(unsigned irq); |
| |
| #define EVTCHN_ROW(e) (e / (PAGE_SIZE/sizeof(**evtchn_to_irq))) |
| #define EVTCHN_COL(e) (e % (PAGE_SIZE/sizeof(**evtchn_to_irq))) |
| #define EVTCHN_PER_ROW (PAGE_SIZE / sizeof(**evtchn_to_irq)) |
| |
| /* Xen will never allocate port zero for any purpose. */ |
| #define VALID_EVTCHN(chn) ((chn) != 0) |
| |
| static struct irq_info *legacy_info_ptrs[NR_IRQS_LEGACY]; |
| |
| static struct irq_chip xen_dynamic_chip; |
| static struct irq_chip xen_lateeoi_chip; |
| static struct irq_chip xen_percpu_chip; |
| static struct irq_chip xen_pirq_chip; |
| static void enable_dynirq(struct irq_data *data); |
| static void disable_dynirq(struct irq_data *data); |
| |
| static DEFINE_PER_CPU(unsigned int, irq_epoch); |
| |
| static void clear_evtchn_to_irq_row(unsigned row) |
| { |
| unsigned col; |
| |
| for (col = 0; col < EVTCHN_PER_ROW; col++) |
| WRITE_ONCE(evtchn_to_irq[row][col], -1); |
| } |
| |
| static void clear_evtchn_to_irq_all(void) |
| { |
| unsigned row; |
| |
| for (row = 0; row < EVTCHN_ROW(xen_evtchn_max_channels()); row++) { |
| if (evtchn_to_irq[row] == NULL) |
| continue; |
| clear_evtchn_to_irq_row(row); |
| } |
| } |
| |
| static int set_evtchn_to_irq(evtchn_port_t evtchn, unsigned int irq) |
| { |
| unsigned row; |
| unsigned col; |
| |
| if (evtchn >= xen_evtchn_max_channels()) |
| return -EINVAL; |
| |
| row = EVTCHN_ROW(evtchn); |
| col = EVTCHN_COL(evtchn); |
| |
| if (evtchn_to_irq[row] == NULL) { |
| /* Unallocated irq entries return -1 anyway */ |
| if (irq == -1) |
| return 0; |
| |
| evtchn_to_irq[row] = (int *)get_zeroed_page(GFP_KERNEL); |
| if (evtchn_to_irq[row] == NULL) |
| return -ENOMEM; |
| |
| clear_evtchn_to_irq_row(row); |
| } |
| |
| WRITE_ONCE(evtchn_to_irq[row][col], irq); |
| return 0; |
| } |
| |
| int get_evtchn_to_irq(evtchn_port_t evtchn) |
| { |
| if (evtchn >= xen_evtchn_max_channels()) |
| return -1; |
| if (evtchn_to_irq[EVTCHN_ROW(evtchn)] == NULL) |
| return -1; |
| return READ_ONCE(evtchn_to_irq[EVTCHN_ROW(evtchn)][EVTCHN_COL(evtchn)]); |
| } |
| |
| /* Get info for IRQ */ |
| static struct irq_info *info_for_irq(unsigned irq) |
| { |
| if (irq < nr_legacy_irqs()) |
| return legacy_info_ptrs[irq]; |
| else |
| return irq_get_chip_data(irq); |
| } |
| |
| static void set_info_for_irq(unsigned int irq, struct irq_info *info) |
| { |
| if (irq < nr_legacy_irqs()) |
| legacy_info_ptrs[irq] = info; |
| else |
| irq_set_chip_data(irq, info); |
| } |
| |
| /* Per CPU channel accounting */ |
| static void channels_on_cpu_dec(struct irq_info *info) |
| { |
| if (!info->is_accounted) |
| return; |
| |
| info->is_accounted = 0; |
| |
| if (WARN_ON_ONCE(info->cpu >= nr_cpu_ids)) |
| return; |
| |
| WARN_ON_ONCE(!atomic_add_unless(&channels_on_cpu[info->cpu], -1 , 0)); |
| } |
| |
| static void channels_on_cpu_inc(struct irq_info *info) |
| { |
| if (WARN_ON_ONCE(info->cpu >= nr_cpu_ids)) |
| return; |
| |
| if (WARN_ON_ONCE(!atomic_add_unless(&channels_on_cpu[info->cpu], 1, |
| INT_MAX))) |
| return; |
| |
| info->is_accounted = 1; |
| } |
| |
| /* Constructors for packed IRQ information. */ |
| static int xen_irq_info_common_setup(struct irq_info *info, |
| unsigned irq, |
| enum xen_irq_type type, |
| evtchn_port_t evtchn, |
| unsigned short cpu) |
| { |
| int ret; |
| |
| BUG_ON(info->type != IRQT_UNBOUND && info->type != type); |
| |
| info->type = type; |
| info->irq = irq; |
| info->evtchn = evtchn; |
| info->cpu = cpu; |
| |
| ret = set_evtchn_to_irq(evtchn, irq); |
| if (ret < 0) |
| return ret; |
| |
| irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN); |
| |
| return xen_evtchn_port_setup(evtchn); |
| } |
| |
| static int xen_irq_info_evtchn_setup(unsigned irq, |
| evtchn_port_t evtchn) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| return xen_irq_info_common_setup(info, irq, IRQT_EVTCHN, evtchn, 0); |
| } |
| |
| static int xen_irq_info_ipi_setup(unsigned cpu, |
| unsigned irq, |
| evtchn_port_t evtchn, |
| enum ipi_vector ipi) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| info->u.ipi = ipi; |
| |
| per_cpu(ipi_to_irq, cpu)[ipi] = irq; |
| |
| return xen_irq_info_common_setup(info, irq, IRQT_IPI, evtchn, 0); |
| } |
| |
| static int xen_irq_info_virq_setup(unsigned cpu, |
| unsigned irq, |
| evtchn_port_t evtchn, |
| unsigned virq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| info->u.virq = virq; |
| |
| per_cpu(virq_to_irq, cpu)[virq] = irq; |
| |
| return xen_irq_info_common_setup(info, irq, IRQT_VIRQ, evtchn, 0); |
| } |
| |
| static int xen_irq_info_pirq_setup(unsigned irq, |
| evtchn_port_t evtchn, |
| unsigned pirq, |
| unsigned gsi, |
| uint16_t domid, |
| unsigned char flags) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| info->u.pirq.pirq = pirq; |
| info->u.pirq.gsi = gsi; |
| info->u.pirq.domid = domid; |
| info->u.pirq.flags = flags; |
| |
| return xen_irq_info_common_setup(info, irq, IRQT_PIRQ, evtchn, 0); |
| } |
| |
| static void xen_irq_info_cleanup(struct irq_info *info) |
| { |
| set_evtchn_to_irq(info->evtchn, -1); |
| info->evtchn = 0; |
| channels_on_cpu_dec(info); |
| } |
| |
| /* |
| * Accessors for packed IRQ information. |
| */ |
| evtchn_port_t evtchn_from_irq(unsigned irq) |
| { |
| const struct irq_info *info = NULL; |
| |
| if (likely(irq < nr_irqs)) |
| info = info_for_irq(irq); |
| if (!info) |
| return 0; |
| |
| return info->evtchn; |
| } |
| |
| unsigned int irq_from_evtchn(evtchn_port_t evtchn) |
| { |
| return get_evtchn_to_irq(evtchn); |
| } |
| EXPORT_SYMBOL_GPL(irq_from_evtchn); |
| |
| int irq_from_virq(unsigned int cpu, unsigned int virq) |
| { |
| return per_cpu(virq_to_irq, cpu)[virq]; |
| } |
| |
| 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 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; |
| } |
| |
| unsigned int cpu_from_evtchn(evtchn_port_t evtchn) |
| { |
| int irq = get_evtchn_to_irq(evtchn); |
| unsigned ret = 0; |
| |
| if (irq != -1) |
| ret = cpu_from_irq(irq); |
| |
| return ret; |
| } |
| |
| #ifdef CONFIG_X86 |
| static bool pirq_check_eoi_map(unsigned irq) |
| { |
| return test_bit(pirq_from_irq(irq), pirq_eoi_map); |
| } |
| #endif |
| |
| static bool pirq_needs_eoi_flag(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 void bind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int cpu, |
| bool force_affinity) |
| { |
| int irq = get_evtchn_to_irq(evtchn); |
| struct irq_info *info = info_for_irq(irq); |
| |
| BUG_ON(irq == -1); |
| |
| if (IS_ENABLED(CONFIG_SMP) && force_affinity) { |
| cpumask_copy(irq_get_affinity_mask(irq), cpumask_of(cpu)); |
| cpumask_copy(irq_get_effective_affinity_mask(irq), |
| cpumask_of(cpu)); |
| } |
| |
| xen_evtchn_port_bind_to_cpu(evtchn, cpu, info->cpu); |
| |
| channels_on_cpu_dec(info); |
| info->cpu = cpu; |
| channels_on_cpu_inc(info); |
| } |
| |
| /** |
| * 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) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| notify_remote_via_evtchn(evtchn); |
| } |
| EXPORT_SYMBOL_GPL(notify_remote_via_irq); |
| |
| struct lateeoi_work { |
| struct delayed_work delayed; |
| spinlock_t eoi_list_lock; |
| struct list_head eoi_list; |
| }; |
| |
| static DEFINE_PER_CPU(struct lateeoi_work, lateeoi); |
| |
| static void lateeoi_list_del(struct irq_info *info) |
| { |
| struct lateeoi_work *eoi = &per_cpu(lateeoi, info->eoi_cpu); |
| unsigned long flags; |
| |
| spin_lock_irqsave(&eoi->eoi_list_lock, flags); |
| list_del_init(&info->eoi_list); |
| spin_unlock_irqrestore(&eoi->eoi_list_lock, flags); |
| } |
| |
| static void lateeoi_list_add(struct irq_info *info) |
| { |
| struct lateeoi_work *eoi = &per_cpu(lateeoi, info->eoi_cpu); |
| struct irq_info *elem; |
| u64 now = get_jiffies_64(); |
| unsigned long delay; |
| unsigned long flags; |
| |
| if (now < info->eoi_time) |
| delay = info->eoi_time - now; |
| else |
| delay = 1; |
| |
| spin_lock_irqsave(&eoi->eoi_list_lock, flags); |
| |
| if (list_empty(&eoi->eoi_list)) { |
| list_add(&info->eoi_list, &eoi->eoi_list); |
| mod_delayed_work_on(info->eoi_cpu, system_wq, |
| &eoi->delayed, delay); |
| } else { |
| list_for_each_entry_reverse(elem, &eoi->eoi_list, eoi_list) { |
| if (elem->eoi_time <= info->eoi_time) |
| break; |
| } |
| list_add(&info->eoi_list, &elem->eoi_list); |
| } |
| |
| spin_unlock_irqrestore(&eoi->eoi_list_lock, flags); |
| } |
| |
| static void xen_irq_lateeoi_locked(struct irq_info *info, bool spurious) |
| { |
| evtchn_port_t evtchn; |
| unsigned int cpu; |
| unsigned int delay = 0; |
| |
| evtchn = info->evtchn; |
| if (!VALID_EVTCHN(evtchn) || !list_empty(&info->eoi_list)) |
| return; |
| |
| if (spurious) { |
| if ((1 << info->spurious_cnt) < (HZ << 2)) { |
| if (info->spurious_cnt != 0xFF) |
| info->spurious_cnt++; |
| } |
| if (info->spurious_cnt > 1) { |
| delay = 1 << (info->spurious_cnt - 2); |
| if (delay > HZ) |
| delay = HZ; |
| if (!info->eoi_time) |
| info->eoi_cpu = smp_processor_id(); |
| info->eoi_time = get_jiffies_64() + delay; |
| } |
| } else { |
| info->spurious_cnt = 0; |
| } |
| |
| cpu = info->eoi_cpu; |
| if (info->eoi_time && |
| (info->irq_epoch == per_cpu(irq_epoch, cpu) || delay)) { |
| lateeoi_list_add(info); |
| return; |
| } |
| |
| info->eoi_time = 0; |
| unmask_evtchn(evtchn); |
| } |
| |
| static void xen_irq_lateeoi_worker(struct work_struct *work) |
| { |
| struct lateeoi_work *eoi; |
| struct irq_info *info; |
| u64 now = get_jiffies_64(); |
| unsigned long flags; |
| |
| eoi = container_of(to_delayed_work(work), struct lateeoi_work, delayed); |
| |
| read_lock_irqsave(&evtchn_rwlock, flags); |
| |
| while (true) { |
| spin_lock(&eoi->eoi_list_lock); |
| |
| info = list_first_entry_or_null(&eoi->eoi_list, struct irq_info, |
| eoi_list); |
| |
| if (info == NULL || now < info->eoi_time) { |
| spin_unlock(&eoi->eoi_list_lock); |
| break; |
| } |
| |
| list_del_init(&info->eoi_list); |
| |
| spin_unlock(&eoi->eoi_list_lock); |
| |
| info->eoi_time = 0; |
| |
| xen_irq_lateeoi_locked(info, false); |
| } |
| |
| if (info) |
| mod_delayed_work_on(info->eoi_cpu, system_wq, |
| &eoi->delayed, info->eoi_time - now); |
| |
| read_unlock_irqrestore(&evtchn_rwlock, flags); |
| } |
| |
| static void xen_cpu_init_eoi(unsigned int cpu) |
| { |
| struct lateeoi_work *eoi = &per_cpu(lateeoi, cpu); |
| |
| INIT_DELAYED_WORK(&eoi->delayed, xen_irq_lateeoi_worker); |
| spin_lock_init(&eoi->eoi_list_lock); |
| INIT_LIST_HEAD(&eoi->eoi_list); |
| } |
| |
| void xen_irq_lateeoi(unsigned int irq, unsigned int eoi_flags) |
| { |
| struct irq_info *info; |
| unsigned long flags; |
| |
| read_lock_irqsave(&evtchn_rwlock, flags); |
| |
| info = info_for_irq(irq); |
| |
| if (info) |
| xen_irq_lateeoi_locked(info, eoi_flags & XEN_EOI_FLAG_SPURIOUS); |
| |
| read_unlock_irqrestore(&evtchn_rwlock, flags); |
| } |
| EXPORT_SYMBOL_GPL(xen_irq_lateeoi); |
| |
| static void xen_irq_init(unsigned irq) |
| { |
| struct irq_info *info; |
| |
| info = kzalloc(sizeof(*info), GFP_KERNEL); |
| if (info == NULL) |
| panic("Unable to allocate metadata for IRQ%d\n", irq); |
| |
| info->type = IRQT_UNBOUND; |
| info->refcnt = -1; |
| |
| set_info_for_irq(irq, info); |
| /* |
| * Interrupt affinity setting can be immediate. No point |
| * in delaying it until an interrupt is handled. |
| */ |
| irq_set_status_flags(irq, IRQ_MOVE_PCNTXT); |
| |
| INIT_LIST_HEAD(&info->eoi_list); |
| list_add_tail(&info->list, &xen_irq_list_head); |
| } |
| |
| static int __must_check xen_allocate_irqs_dynamic(int nvec) |
| { |
| int i, irq = irq_alloc_descs(-1, 0, nvec, -1); |
| |
| if (irq >= 0) { |
| for (i = 0; i < nvec; i++) |
| xen_irq_init(irq + i); |
| } |
| |
| return irq; |
| } |
| |
| static inline int __must_check xen_allocate_irq_dynamic(void) |
| { |
| |
| return xen_allocate_irqs_dynamic(1); |
| } |
| |
| static int __must_check xen_allocate_irq_gsi(unsigned gsi) |
| { |
| int irq; |
| |
| /* |
| * A PV guest has no concept of a GSI (since it has no ACPI |
| * nor access to/knowledge of the physical APICs). Therefore |
| * all IRQs are dynamically allocated from the entire IRQ |
| * space. |
| */ |
| if (xen_pv_domain() && !xen_initial_domain()) |
| return xen_allocate_irq_dynamic(); |
| |
| /* Legacy IRQ descriptors are already allocated by the arch. */ |
| if (gsi < nr_legacy_irqs()) |
| irq = gsi; |
| else |
| irq = irq_alloc_desc_at(gsi, -1); |
| |
| xen_irq_init(irq); |
| |
| return irq; |
| } |
| |
| static void xen_free_irq(unsigned irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| unsigned long flags; |
| |
| if (WARN_ON(!info)) |
| return; |
| |
| write_lock_irqsave(&evtchn_rwlock, flags); |
| |
| if (!list_empty(&info->eoi_list)) |
| lateeoi_list_del(info); |
| |
| list_del(&info->list); |
| |
| set_info_for_irq(irq, NULL); |
| |
| WARN_ON(info->refcnt > 0); |
| |
| write_unlock_irqrestore(&evtchn_rwlock, flags); |
| |
| kfree(info); |
| |
| /* Legacy IRQ descriptors are managed by the arch. */ |
| if (irq < nr_legacy_irqs()) |
| return; |
| |
| irq_free_desc(irq); |
| } |
| |
| static void xen_evtchn_close(evtchn_port_t port) |
| { |
| struct evtchn_close close; |
| |
| close.port = port; |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0) |
| BUG(); |
| } |
| |
| 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 void eoi_pirq(struct irq_data *data) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(data->irq); |
| struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) }; |
| int rc = 0; |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return; |
| |
| clear_evtchn(evtchn); |
| |
| if (pirq_needs_eoi(data->irq)) { |
| rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi); |
| WARN_ON(rc); |
| } |
| } |
| |
| static void mask_ack_pirq(struct irq_data *data) |
| { |
| disable_dynirq(data); |
| eoi_pirq(data); |
| } |
| |
| static unsigned int __startup_pirq(unsigned int irq) |
| { |
| struct evtchn_bind_pirq bind_pirq; |
| struct irq_info *info = info_for_irq(irq); |
| evtchn_port_t 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) { |
| pr_warn("Failed to obtain physical IRQ %d\n", irq); |
| return 0; |
| } |
| evtchn = bind_pirq.port; |
| |
| pirq_query_unmask(irq); |
| |
| rc = set_evtchn_to_irq(evtchn, irq); |
| if (rc) |
| goto err; |
| |
| info->evtchn = evtchn; |
| bind_evtchn_to_cpu(evtchn, 0, false); |
| |
| rc = xen_evtchn_port_setup(evtchn); |
| if (rc) |
| goto err; |
| |
| out: |
| unmask_evtchn(evtchn); |
| eoi_pirq(irq_get_irq_data(irq)); |
| |
| return 0; |
| |
| err: |
| pr_err("irq%d: Failed to set port to irq mapping (%d)\n", irq, rc); |
| xen_evtchn_close(evtchn); |
| return 0; |
| } |
| |
| static unsigned int startup_pirq(struct irq_data *data) |
| { |
| return __startup_pirq(data->irq); |
| } |
| |
| static void shutdown_pirq(struct irq_data *data) |
| { |
| unsigned int irq = data->irq; |
| struct irq_info *info = info_for_irq(irq); |
| evtchn_port_t evtchn = evtchn_from_irq(irq); |
| |
| BUG_ON(info->type != IRQT_PIRQ); |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return; |
| |
| mask_evtchn(evtchn); |
| xen_evtchn_close(evtchn); |
| xen_irq_info_cleanup(info); |
| } |
| |
| static void enable_pirq(struct irq_data *data) |
| { |
| enable_dynirq(data); |
| } |
| |
| static void disable_pirq(struct irq_data *data) |
| { |
| disable_dynirq(data); |
| } |
| |
| int xen_irq_from_gsi(unsigned gsi) |
| { |
| struct irq_info *info; |
| |
| list_for_each_entry(info, &xen_irq_list_head, list) { |
| if (info->type != IRQT_PIRQ) |
| continue; |
| |
| if (info->u.pirq.gsi == gsi) |
| return info->irq; |
| } |
| |
| return -1; |
| } |
| EXPORT_SYMBOL_GPL(xen_irq_from_gsi); |
| |
| static void __unbind_from_irq(unsigned int irq) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(irq); |
| struct irq_info *info = info_for_irq(irq); |
| |
| if (info->refcnt > 0) { |
| info->refcnt--; |
| if (info->refcnt != 0) |
| return; |
| } |
| |
| if (VALID_EVTCHN(evtchn)) { |
| unsigned int cpu = cpu_from_irq(irq); |
| |
| xen_evtchn_close(evtchn); |
| |
| switch (type_from_irq(irq)) { |
| case IRQT_VIRQ: |
| per_cpu(virq_to_irq, cpu)[virq_from_irq(irq)] = -1; |
| break; |
| case IRQT_IPI: |
| per_cpu(ipi_to_irq, cpu)[ipi_from_irq(irq)] = -1; |
| break; |
| default: |
| break; |
| } |
| |
| xen_irq_info_cleanup(info); |
| } |
| |
| xen_free_irq(irq); |
| } |
| |
| /* |
| * Do not make any assumptions regarding the relationship between the |
| * IRQ number returned here and the Xen pirq 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. |
| * |
| * Shareable implies level triggered, not shareable implies edge |
| * triggered here. |
| */ |
| int xen_bind_pirq_gsi_to_irq(unsigned gsi, |
| unsigned pirq, int shareable, char *name) |
| { |
| int irq = -1; |
| struct physdev_irq irq_op; |
| int ret; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = xen_irq_from_gsi(gsi); |
| if (irq != -1) { |
| pr_info("%s: returning irq %d for gsi %u\n", |
| __func__, irq, gsi); |
| goto out; |
| } |
| |
| irq = xen_allocate_irq_gsi(gsi); |
| if (irq < 0) |
| goto out; |
| |
| 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)) { |
| xen_free_irq(irq); |
| irq = -ENOSPC; |
| goto out; |
| } |
| |
| ret = xen_irq_info_pirq_setup(irq, 0, pirq, gsi, DOMID_SELF, |
| shareable ? PIRQ_SHAREABLE : 0); |
| if (ret < 0) { |
| __unbind_from_irq(irq); |
| irq = ret; |
| goto out; |
| } |
| |
| pirq_query_unmask(irq); |
| /* We try to use the handler with the appropriate semantic for the |
| * type of interrupt: if the interrupt is an edge triggered |
| * interrupt we use handle_edge_irq. |
| * |
| * On the other hand if the interrupt is level triggered we use |
| * handle_fasteoi_irq like the native code does for this kind of |
| * interrupts. |
| * |
| * Depending on the Xen version, pirq_needs_eoi might return true |
| * not only for level triggered interrupts but for edge triggered |
| * interrupts too. In any case Xen always honors the eoi mechanism, |
| * not injecting any more pirqs of the same kind if the first one |
| * hasn't received an eoi yet. Therefore using the fasteoi handler |
| * is the right choice either way. |
| */ |
| if (shareable) |
| irq_set_chip_and_handler_name(irq, &xen_pirq_chip, |
| handle_fasteoi_irq, name); |
| else |
| irq_set_chip_and_handler_name(irq, &xen_pirq_chip, |
| handle_edge_irq, name); |
| |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| #ifdef CONFIG_PCI_MSI |
| int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc) |
| { |
| int rc; |
| struct physdev_get_free_pirq op_get_free_pirq; |
| |
| op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI; |
| rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq); |
| |
| WARN_ONCE(rc == -ENOSYS, |
| "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n"); |
| |
| return rc ? -1 : op_get_free_pirq.pirq; |
| } |
| |
| int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc, |
| int pirq, int nvec, const char *name, domid_t domid) |
| { |
| int i, irq, ret; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = xen_allocate_irqs_dynamic(nvec); |
| if (irq < 0) |
| goto out; |
| |
| for (i = 0; i < nvec; i++) { |
| irq_set_chip_and_handler_name(irq + i, &xen_pirq_chip, handle_edge_irq, name); |
| |
| ret = xen_irq_info_pirq_setup(irq + i, 0, pirq + i, 0, domid, |
| i == 0 ? 0 : PIRQ_MSI_GROUP); |
| if (ret < 0) |
| goto error_irq; |
| } |
| |
| ret = irq_set_msi_desc(irq, msidesc); |
| if (ret < 0) |
| goto error_irq; |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| return irq; |
| error_irq: |
| while (nvec--) |
| __unbind_from_irq(irq + nvec); |
| mutex_unlock(&irq_mapping_update_lock); |
| return ret; |
| } |
| #endif |
| |
| int xen_destroy_irq(int irq) |
| { |
| struct physdev_unmap_pirq unmap_irq; |
| struct irq_info *info = info_for_irq(irq); |
| int rc = -ENOENT; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| /* |
| * If trying to remove a vector in a MSI group different |
| * than the first one skip the PIRQ unmap unless this vector |
| * is the first one in the group. |
| */ |
| if (xen_initial_domain() && !(info->u.pirq.flags & PIRQ_MSI_GROUP)) { |
| unmap_irq.pirq = info->u.pirq.pirq; |
| unmap_irq.domid = info->u.pirq.domid; |
| rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq); |
| /* If another domain quits without making the pci_disable_msix |
| * call, the Xen hypervisor takes care of freeing the PIRQs |
| * (free_domain_pirqs). |
| */ |
| if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF)) |
| pr_info("domain %d does not have %d anymore\n", |
| info->u.pirq.domid, info->u.pirq.pirq); |
| else if (rc) { |
| pr_warn("unmap irq failed %d\n", rc); |
| goto out; |
| } |
| } |
| |
| xen_free_irq(irq); |
| |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| return rc; |
| } |
| |
| int xen_irq_from_pirq(unsigned pirq) |
| { |
| int irq; |
| |
| struct irq_info *info; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| list_for_each_entry(info, &xen_irq_list_head, list) { |
| if (info->type != IRQT_PIRQ) |
| continue; |
| irq = info->irq; |
| if (info->u.pirq.pirq == pirq) |
| goto out; |
| } |
| irq = -1; |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| |
| int xen_pirq_from_irq(unsigned irq) |
| { |
| return pirq_from_irq(irq); |
| } |
| EXPORT_SYMBOL_GPL(xen_pirq_from_irq); |
| |
| static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip) |
| { |
| int irq; |
| int ret; |
| |
| if (evtchn >= xen_evtchn_max_channels()) |
| return -ENOMEM; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = get_evtchn_to_irq(evtchn); |
| |
| if (irq == -1) { |
| irq = xen_allocate_irq_dynamic(); |
| if (irq < 0) |
| goto out; |
| |
| irq_set_chip_and_handler_name(irq, chip, |
| handle_edge_irq, "event"); |
| |
| ret = xen_irq_info_evtchn_setup(irq, evtchn); |
| if (ret < 0) { |
| __unbind_from_irq(irq); |
| irq = ret; |
| goto out; |
| } |
| /* |
| * New interdomain events are initially bound to vCPU0 This |
| * is required to setup the event channel in the first |
| * place and also important for UP guests because the |
| * affinity setting is not invoked on them so nothing would |
| * bind the channel. |
| */ |
| bind_evtchn_to_cpu(evtchn, 0, false); |
| } else { |
| struct irq_info *info = info_for_irq(irq); |
| WARN_ON(info == NULL || info->type != IRQT_EVTCHN); |
| } |
| |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| int bind_evtchn_to_irq(evtchn_port_t evtchn) |
| { |
| return bind_evtchn_to_irq_chip(evtchn, &xen_dynamic_chip); |
| } |
| 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; |
| evtchn_port_t evtchn; |
| int ret, irq; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = per_cpu(ipi_to_irq, cpu)[ipi]; |
| |
| if (irq == -1) { |
| irq = xen_allocate_irq_dynamic(); |
| if (irq < 0) |
| goto out; |
| |
| irq_set_chip_and_handler_name(irq, &xen_percpu_chip, |
| handle_percpu_irq, "ipi"); |
| |
| bind_ipi.vcpu = xen_vcpu_nr(cpu); |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, |
| &bind_ipi) != 0) |
| BUG(); |
| evtchn = bind_ipi.port; |
| |
| ret = xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi); |
| if (ret < 0) { |
| __unbind_from_irq(irq); |
| irq = ret; |
| goto out; |
| } |
| /* |
| * Force the affinity mask to the target CPU so proc shows |
| * the correct target. |
| */ |
| bind_evtchn_to_cpu(evtchn, cpu, true); |
| } else { |
| struct irq_info *info = info_for_irq(irq); |
| WARN_ON(info == NULL || info->type != IRQT_IPI); |
| } |
| |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| return irq; |
| } |
| |
| static int bind_interdomain_evtchn_to_irq_chip(unsigned int remote_domain, |
| evtchn_port_t remote_port, |
| struct irq_chip *chip) |
| { |
| struct evtchn_bind_interdomain bind_interdomain; |
| int err; |
| |
| bind_interdomain.remote_dom = remote_domain; |
| bind_interdomain.remote_port = remote_port; |
| |
| err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain, |
| &bind_interdomain); |
| |
| return err ? : bind_evtchn_to_irq_chip(bind_interdomain.local_port, |
| chip); |
| } |
| |
| int bind_interdomain_evtchn_to_irq_lateeoi(unsigned int remote_domain, |
| evtchn_port_t remote_port) |
| { |
| return bind_interdomain_evtchn_to_irq_chip(remote_domain, remote_port, |
| &xen_lateeoi_chip); |
| } |
| EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq_lateeoi); |
| |
| static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn) |
| { |
| struct evtchn_status status; |
| evtchn_port_t port; |
| int rc = -ENOENT; |
| |
| memset(&status, 0, sizeof(status)); |
| for (port = 0; port < xen_evtchn_max_channels(); port++) { |
| status.dom = DOMID_SELF; |
| status.port = port; |
| rc = HYPERVISOR_event_channel_op(EVTCHNOP_status, &status); |
| if (rc < 0) |
| continue; |
| if (status.status != EVTCHNSTAT_virq) |
| continue; |
| if (status.u.virq == virq && status.vcpu == xen_vcpu_nr(cpu)) { |
| *evtchn = port; |
| break; |
| } |
| } |
| return rc; |
| } |
| |
| /** |
| * xen_evtchn_nr_channels - number of usable event channel ports |
| * |
| * This may be less than the maximum supported by the current |
| * hypervisor ABI. Use xen_evtchn_max_channels() for the maximum |
| * supported. |
| */ |
| unsigned xen_evtchn_nr_channels(void) |
| { |
| return evtchn_ops->nr_channels(); |
| } |
| EXPORT_SYMBOL_GPL(xen_evtchn_nr_channels); |
| |
| int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu) |
| { |
| struct evtchn_bind_virq bind_virq; |
| evtchn_port_t evtchn = 0; |
| int irq, ret; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = per_cpu(virq_to_irq, cpu)[virq]; |
| |
| if (irq == -1) { |
| irq = xen_allocate_irq_dynamic(); |
| if (irq < 0) |
| goto out; |
| |
| if (percpu) |
| irq_set_chip_and_handler_name(irq, &xen_percpu_chip, |
| handle_percpu_irq, "virq"); |
| else |
| irq_set_chip_and_handler_name(irq, &xen_dynamic_chip, |
| handle_edge_irq, "virq"); |
| |
| bind_virq.virq = virq; |
| bind_virq.vcpu = xen_vcpu_nr(cpu); |
| ret = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, |
| &bind_virq); |
| if (ret == 0) |
| evtchn = bind_virq.port; |
| else { |
| if (ret == -EEXIST) |
| ret = find_virq(virq, cpu, &evtchn); |
| BUG_ON(ret < 0); |
| } |
| |
| ret = xen_irq_info_virq_setup(cpu, irq, evtchn, virq); |
| if (ret < 0) { |
| __unbind_from_irq(irq); |
| irq = ret; |
| goto out; |
| } |
| |
| /* |
| * Force the affinity mask for percpu interrupts so proc |
| * shows the correct target. |
| */ |
| bind_evtchn_to_cpu(evtchn, cpu, percpu); |
| } else { |
| struct irq_info *info = info_for_irq(irq); |
| WARN_ON(info == NULL || info->type != IRQT_VIRQ); |
| } |
| |
| out: |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| return irq; |
| } |
| |
| static void unbind_from_irq(unsigned int irq) |
| { |
| mutex_lock(&irq_mapping_update_lock); |
| __unbind_from_irq(irq); |
| mutex_unlock(&irq_mapping_update_lock); |
| } |
| |
| static int bind_evtchn_to_irqhandler_chip(evtchn_port_t evtchn, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, void *dev_id, |
| struct irq_chip *chip) |
| { |
| int irq, retval; |
| |
| irq = bind_evtchn_to_irq_chip(evtchn, chip); |
| if (irq < 0) |
| return irq; |
| retval = request_irq(irq, handler, irqflags, devname, dev_id); |
| if (retval != 0) { |
| unbind_from_irq(irq); |
| return retval; |
| } |
| |
| return irq; |
| } |
| |
| int bind_evtchn_to_irqhandler(evtchn_port_t evtchn, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, void *dev_id) |
| { |
| return bind_evtchn_to_irqhandler_chip(evtchn, handler, irqflags, |
| devname, dev_id, |
| &xen_dynamic_chip); |
| } |
| EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler); |
| |
| int bind_evtchn_to_irqhandler_lateeoi(evtchn_port_t evtchn, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, void *dev_id) |
| { |
| return bind_evtchn_to_irqhandler_chip(evtchn, handler, irqflags, |
| devname, dev_id, |
| &xen_lateeoi_chip); |
| } |
| EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler_lateeoi); |
| |
| static int bind_interdomain_evtchn_to_irqhandler_chip( |
| unsigned int remote_domain, evtchn_port_t remote_port, |
| irq_handler_t handler, unsigned long irqflags, |
| const char *devname, void *dev_id, struct irq_chip *chip) |
| { |
| int irq, retval; |
| |
| irq = bind_interdomain_evtchn_to_irq_chip(remote_domain, remote_port, |
| chip); |
| if (irq < 0) |
| return irq; |
| |
| retval = request_irq(irq, handler, irqflags, devname, dev_id); |
| if (retval != 0) { |
| unbind_from_irq(irq); |
| return retval; |
| } |
| |
| return irq; |
| } |
| |
| int bind_interdomain_evtchn_to_irqhandler_lateeoi(unsigned int remote_domain, |
| evtchn_port_t remote_port, |
| irq_handler_t handler, |
| unsigned long irqflags, |
| const char *devname, |
| void *dev_id) |
| { |
| return bind_interdomain_evtchn_to_irqhandler_chip(remote_domain, |
| remote_port, handler, irqflags, devname, |
| dev_id, &xen_lateeoi_chip); |
| } |
| EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler_lateeoi); |
| |
| int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, |
| irq_handler_t handler, |
| unsigned long irqflags, const char *devname, void *dev_id) |
| { |
| int irq, retval; |
| |
| irq = bind_virq_to_irq(virq, cpu, irqflags & IRQF_PERCPU); |
| if (irq < 0) |
| return irq; |
| 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 | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME; |
| 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) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| if (WARN_ON(!info)) |
| return; |
| free_irq(irq, dev_id); |
| unbind_from_irq(irq); |
| } |
| EXPORT_SYMBOL_GPL(unbind_from_irqhandler); |
| |
| /** |
| * xen_set_irq_priority() - set an event channel priority. |
| * @irq:irq bound to an event channel. |
| * @priority: priority between XEN_IRQ_PRIORITY_MAX and XEN_IRQ_PRIORITY_MIN. |
| */ |
| int xen_set_irq_priority(unsigned irq, unsigned priority) |
| { |
| struct evtchn_set_priority set_priority; |
| |
| set_priority.port = evtchn_from_irq(irq); |
| set_priority.priority = priority; |
| |
| return HYPERVISOR_event_channel_op(EVTCHNOP_set_priority, |
| &set_priority); |
| } |
| EXPORT_SYMBOL_GPL(xen_set_irq_priority); |
| |
| int evtchn_make_refcounted(evtchn_port_t evtchn) |
| { |
| int irq = get_evtchn_to_irq(evtchn); |
| struct irq_info *info; |
| |
| if (irq == -1) |
| return -ENOENT; |
| |
| info = info_for_irq(irq); |
| |
| if (!info) |
| return -ENOENT; |
| |
| WARN_ON(info->refcnt != -1); |
| |
| info->refcnt = 1; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(evtchn_make_refcounted); |
| |
| int evtchn_get(evtchn_port_t evtchn) |
| { |
| int irq; |
| struct irq_info *info; |
| int err = -ENOENT; |
| |
| if (evtchn >= xen_evtchn_max_channels()) |
| return -EINVAL; |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| irq = get_evtchn_to_irq(evtchn); |
| if (irq == -1) |
| goto done; |
| |
| info = info_for_irq(irq); |
| |
| if (!info) |
| goto done; |
| |
| err = -EINVAL; |
| if (info->refcnt <= 0 || info->refcnt == SHRT_MAX) |
| goto done; |
| |
| info->refcnt++; |
| err = 0; |
| done: |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(evtchn_get); |
| |
| void evtchn_put(evtchn_port_t evtchn) |
| { |
| int irq = get_evtchn_to_irq(evtchn); |
| if (WARN_ON(irq == -1)) |
| return; |
| unbind_from_irq(irq); |
| } |
| EXPORT_SYMBOL_GPL(evtchn_put); |
| |
| void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector) |
| { |
| int irq; |
| |
| #ifdef CONFIG_X86 |
| if (unlikely(vector == XEN_NMI_VECTOR)) { |
| int rc = HYPERVISOR_vcpu_op(VCPUOP_send_nmi, xen_vcpu_nr(cpu), |
| NULL); |
| if (rc < 0) |
| printk(KERN_WARNING "Sending nmi to CPU%d failed (rc:%d)\n", cpu, rc); |
| return; |
| } |
| #endif |
| irq = per_cpu(ipi_to_irq, cpu)[vector]; |
| BUG_ON(irq < 0); |
| notify_remote_via_irq(irq); |
| } |
| |
| struct evtchn_loop_ctrl { |
| ktime_t timeout; |
| unsigned count; |
| bool defer_eoi; |
| }; |
| |
| void handle_irq_for_port(evtchn_port_t port, struct evtchn_loop_ctrl *ctrl) |
| { |
| int irq; |
| struct irq_info *info; |
| |
| irq = get_evtchn_to_irq(port); |
| if (irq == -1) |
| return; |
| |
| /* |
| * Check for timeout every 256 events. |
| * We are setting the timeout value only after the first 256 |
| * events in order to not hurt the common case of few loop |
| * iterations. The 256 is basically an arbitrary value. |
| * |
| * In case we are hitting the timeout we need to defer all further |
| * EOIs in order to ensure to leave the event handling loop rather |
| * sooner than later. |
| */ |
| if (!ctrl->defer_eoi && !(++ctrl->count & 0xff)) { |
| ktime_t kt = ktime_get(); |
| |
| if (!ctrl->timeout) { |
| kt = ktime_add_ms(kt, |
| jiffies_to_msecs(event_loop_timeout)); |
| ctrl->timeout = kt; |
| } else if (kt > ctrl->timeout) { |
| ctrl->defer_eoi = true; |
| } |
| } |
| |
| info = info_for_irq(irq); |
| |
| if (ctrl->defer_eoi) { |
| info->eoi_cpu = smp_processor_id(); |
| info->irq_epoch = __this_cpu_read(irq_epoch); |
| info->eoi_time = get_jiffies_64() + event_eoi_delay; |
| } |
| |
| generic_handle_irq(irq); |
| } |
| |
| static void __xen_evtchn_do_upcall(void) |
| { |
| struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); |
| int cpu = smp_processor_id(); |
| struct evtchn_loop_ctrl ctrl = { 0 }; |
| |
| read_lock(&evtchn_rwlock); |
| |
| do { |
| vcpu_info->evtchn_upcall_pending = 0; |
| |
| xen_evtchn_handle_events(cpu, &ctrl); |
| |
| BUG_ON(!irqs_disabled()); |
| |
| virt_rmb(); /* Hypervisor can set upcall pending. */ |
| |
| } while (vcpu_info->evtchn_upcall_pending); |
| |
| read_unlock(&evtchn_rwlock); |
| |
| /* |
| * Increment irq_epoch only now to defer EOIs only for |
| * xen_irq_lateeoi() invocations occurring from inside the loop |
| * above. |
| */ |
| __this_cpu_inc(irq_epoch); |
| } |
| |
| void xen_evtchn_do_upcall(struct pt_regs *regs) |
| { |
| struct pt_regs *old_regs = set_irq_regs(regs); |
| |
| 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(evtchn_port_t evtchn, int irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| |
| if (WARN_ON(!info)) |
| return; |
| |
| /* Make sure the irq is masked, since the new event channel |
| will also be masked. */ |
| disable_irq(irq); |
| |
| mutex_lock(&irq_mapping_update_lock); |
| |
| /* After resume the irq<->evtchn mappings are all cleared out */ |
| BUG_ON(get_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); |
| |
| (void)xen_irq_info_evtchn_setup(irq, evtchn); |
| |
| mutex_unlock(&irq_mapping_update_lock); |
| |
| bind_evtchn_to_cpu(evtchn, info->cpu, false); |
| |
| /* Unmask the event channel. */ |
| enable_irq(irq); |
| } |
| |
| /* Rebind an evtchn so that it gets delivered to a specific cpu */ |
| static int xen_rebind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int tcpu) |
| { |
| struct evtchn_bind_vcpu bind_vcpu; |
| int masked; |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return -1; |
| |
| if (!xen_support_evtchn_rebind()) |
| return -1; |
| |
| /* Send future instances of this interrupt to other vcpu. */ |
| bind_vcpu.port = evtchn; |
| bind_vcpu.vcpu = xen_vcpu_nr(tcpu); |
| |
| /* |
| * Mask the event while changing the VCPU binding to prevent |
| * it being delivered on an unexpected VCPU. |
| */ |
| masked = test_and_set_mask(evtchn); |
| |
| /* |
| * 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, false); |
| |
| if (!masked) |
| unmask_evtchn(evtchn); |
| |
| return 0; |
| } |
| |
| /* |
| * Find the CPU within @dest mask which has the least number of channels |
| * assigned. This is not precise as the per cpu counts can be modified |
| * concurrently. |
| */ |
| static unsigned int select_target_cpu(const struct cpumask *dest) |
| { |
| unsigned int cpu, best_cpu = UINT_MAX, minch = UINT_MAX; |
| |
| for_each_cpu_and(cpu, dest, cpu_online_mask) { |
| unsigned int curch = atomic_read(&channels_on_cpu[cpu]); |
| |
| if (curch < minch) { |
| minch = curch; |
| best_cpu = cpu; |
| } |
| } |
| |
| /* |
| * Catch the unlikely case that dest contains no online CPUs. Can't |
| * recurse. |
| */ |
| if (best_cpu == UINT_MAX) |
| return select_target_cpu(cpu_online_mask); |
| |
| return best_cpu; |
| } |
| |
| static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest, |
| bool force) |
| { |
| unsigned int tcpu = select_target_cpu(dest); |
| int ret; |
| |
| ret = xen_rebind_evtchn_to_cpu(evtchn_from_irq(data->irq), tcpu); |
| if (!ret) |
| irq_data_update_effective_affinity(data, cpumask_of(tcpu)); |
| |
| return ret; |
| } |
| |
| static void enable_dynirq(struct irq_data *data) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(data->irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| unmask_evtchn(evtchn); |
| } |
| |
| static void disable_dynirq(struct irq_data *data) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(data->irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| mask_evtchn(evtchn); |
| } |
| |
| static void ack_dynirq(struct irq_data *data) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(data->irq); |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return; |
| |
| clear_evtchn(evtchn); |
| } |
| |
| static void mask_ack_dynirq(struct irq_data *data) |
| { |
| disable_dynirq(data); |
| ack_dynirq(data); |
| } |
| |
| static int retrigger_dynirq(struct irq_data *data) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(data->irq); |
| int masked; |
| |
| if (!VALID_EVTCHN(evtchn)) |
| return 0; |
| |
| masked = test_and_set_mask(evtchn); |
| set_evtchn(evtchn); |
| if (!masked) |
| unmask_evtchn(evtchn); |
| |
| return 1; |
| } |
| |
| static void restore_pirqs(void) |
| { |
| int pirq, rc, irq, gsi; |
| struct physdev_map_pirq map_irq; |
| struct irq_info *info; |
| |
| list_for_each_entry(info, &xen_irq_list_head, list) { |
| if (info->type != IRQT_PIRQ) |
| continue; |
| |
| pirq = info->u.pirq.pirq; |
| gsi = info->u.pirq.gsi; |
| irq = info->irq; |
| |
| /* save/restore of PT devices doesn't work, so at this point the |
| * only devices present are GSI based emulated devices */ |
| 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) { |
| pr_warn("xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n", |
| gsi, irq, pirq, rc); |
| xen_free_irq(irq); |
| 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; |
| evtchn_port_t evtchn; |
| int virq, irq; |
| |
| 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 = xen_vcpu_nr(cpu); |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, |
| &bind_virq) != 0) |
| BUG(); |
| evtchn = bind_virq.port; |
| |
| /* Record the new mapping. */ |
| (void)xen_irq_info_virq_setup(cpu, irq, evtchn, virq); |
| /* The affinity mask is still valid */ |
| bind_evtchn_to_cpu(evtchn, cpu, false); |
| } |
| } |
| |
| static void restore_cpu_ipis(unsigned int cpu) |
| { |
| struct evtchn_bind_ipi bind_ipi; |
| evtchn_port_t evtchn; |
| int ipi, irq; |
| |
| 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 = xen_vcpu_nr(cpu); |
| if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi, |
| &bind_ipi) != 0) |
| BUG(); |
| evtchn = bind_ipi.port; |
| |
| /* Record the new mapping. */ |
| (void)xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi); |
| /* The affinity mask is still valid */ |
| bind_evtchn_to_cpu(evtchn, cpu, false); |
| } |
| } |
| |
| /* Clear an irq's pending state, in preparation for polling on it */ |
| void xen_clear_irq_pending(int irq) |
| { |
| evtchn_port_t 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) |
| { |
| evtchn_port_t evtchn = evtchn_from_irq(irq); |
| |
| if (VALID_EVTCHN(evtchn)) |
| set_evtchn(evtchn); |
| } |
| |
| bool xen_test_irq_pending(int irq) |
| { |
| evtchn_port_t 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 */); |
| } |
| |
| /* Check whether the IRQ line is shared with other guests. */ |
| int xen_test_irq_shared(int irq) |
| { |
| struct irq_info *info = info_for_irq(irq); |
| struct physdev_irq_status_query irq_status; |
| |
| if (WARN_ON(!info)) |
| return -ENOENT; |
| |
| irq_status.irq = info->u.pirq.pirq; |
| |
| if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status)) |
| return 0; |
| return !(irq_status.flags & XENIRQSTAT_shared); |
| } |
| EXPORT_SYMBOL_GPL(xen_test_irq_shared); |
| |
| void xen_irq_resume(void) |
| { |
| unsigned int cpu; |
| struct irq_info *info; |
| |
| /* New event-channel space is not 'live' yet. */ |
| xen_evtchn_resume(); |
| |
| /* No IRQ <-> event-channel mappings. */ |
| list_for_each_entry(info, &xen_irq_list_head, list) { |
| /* Zap event-channel binding */ |
| info->evtchn = 0; |
| /* Adjust accounting */ |
| channels_on_cpu_dec(info); |
| } |
| |
| clear_evtchn_to_irq_all(); |
| |
| for_each_possible_cpu(cpu) { |
| restore_cpu_virqs(cpu); |
| restore_cpu_ipis(cpu); |
| } |
| |
| restore_pirqs(); |
| } |
| |
| static struct irq_chip xen_dynamic_chip __read_mostly = { |
| .name = "xen-dyn", |
| |
| .irq_disable = disable_dynirq, |
| .irq_mask = disable_dynirq, |
| .irq_unmask = enable_dynirq, |
| |
| .irq_ack = ack_dynirq, |
| .irq_mask_ack = mask_ack_dynirq, |
| |
| .irq_set_affinity = set_affinity_irq, |
| .irq_retrigger = retrigger_dynirq, |
| }; |
| |
| static struct irq_chip xen_lateeoi_chip __read_mostly = { |
| /* The chip name needs to contain "xen-dyn" for irqbalance to work. */ |
| .name = "xen-dyn-lateeoi", |
| |
| .irq_disable = disable_dynirq, |
| .irq_mask = disable_dynirq, |
| .irq_unmask = enable_dynirq, |
| |
| .irq_ack = mask_ack_dynirq, |
| .irq_mask_ack = mask_ack_dynirq, |
| |
| .irq_set_affinity = set_affinity_irq, |
| .irq_retrigger = retrigger_dynirq, |
| }; |
| |
| static struct irq_chip xen_pirq_chip __read_mostly = { |
| .name = "xen-pirq", |
| |
| .irq_startup = startup_pirq, |
| .irq_shutdown = shutdown_pirq, |
| .irq_enable = enable_pirq, |
| .irq_disable = disable_pirq, |
| |
| .irq_mask = disable_dynirq, |
| .irq_unmask = enable_dynirq, |
| |
| .irq_ack = eoi_pirq, |
| .irq_eoi = eoi_pirq, |
| .irq_mask_ack = mask_ack_pirq, |
| |
| .irq_set_affinity = set_affinity_irq, |
| |
| .irq_retrigger = retrigger_dynirq, |
| }; |
| |
| static struct irq_chip xen_percpu_chip __read_mostly = { |
| .name = "xen-percpu", |
| |
| .irq_disable = disable_dynirq, |
| .irq_mask = disable_dynirq, |
| .irq_unmask = enable_dynirq, |
| |
| .irq_ack = ack_dynirq, |
| }; |
| |
| #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_setup_callback_vector(void) |
| { |
| uint64_t callback_via; |
| |
| if (xen_have_vector_callback) { |
| callback_via = HVM_CALLBACK_VECTOR(HYPERVISOR_CALLBACK_VECTOR); |
| if (xen_set_callback_via(callback_via)) { |
| pr_err("Request for Xen HVM callback vector failed\n"); |
| xen_have_vector_callback = 0; |
| } |
| } |
| } |
| |
| static __init void xen_alloc_callback_vector(void) |
| { |
| if (!xen_have_vector_callback) |
| return; |
| |
| pr_info("Xen HVM callback vector for event delivery is enabled\n"); |
| alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_xen_hvm_callback); |
| } |
| #else |
| void xen_setup_callback_vector(void) {} |
| static inline void xen_alloc_callback_vector(void) {} |
| #endif |
| |
| bool xen_fifo_events = true; |
| module_param_named(fifo_events, xen_fifo_events, bool, 0); |
| |
| static int xen_evtchn_cpu_prepare(unsigned int cpu) |
| { |
| int ret = 0; |
| |
| xen_cpu_init_eoi(cpu); |
| |
| if (evtchn_ops->percpu_init) |
| ret = evtchn_ops->percpu_init(cpu); |
| |
| return ret; |
| } |
| |
| static int xen_evtchn_cpu_dead(unsigned int cpu) |
| { |
| int ret = 0; |
| |
| if (evtchn_ops->percpu_deinit) |
| ret = evtchn_ops->percpu_deinit(cpu); |
| |
| return ret; |
| } |
| |
| void __init xen_init_IRQ(void) |
| { |
| int ret = -EINVAL; |
| evtchn_port_t evtchn; |
| |
| if (xen_fifo_events) |
| ret = xen_evtchn_fifo_init(); |
| if (ret < 0) { |
| xen_evtchn_2l_init(); |
| xen_fifo_events = false; |
| } |
| |
| xen_cpu_init_eoi(smp_processor_id()); |
| |
| cpuhp_setup_state_nocalls(CPUHP_XEN_EVTCHN_PREPARE, |
| "xen/evtchn:prepare", |
| xen_evtchn_cpu_prepare, xen_evtchn_cpu_dead); |
| |
| evtchn_to_irq = kcalloc(EVTCHN_ROW(xen_evtchn_max_channels()), |
| sizeof(*evtchn_to_irq), GFP_KERNEL); |
| BUG_ON(!evtchn_to_irq); |
| |
| /* No event channels are 'live' right now. */ |
| for (evtchn = 0; evtchn < xen_evtchn_nr_channels(); evtchn++) |
| mask_evtchn(evtchn); |
| |
| pirq_needs_eoi = pirq_needs_eoi_flag; |
| |
| #ifdef CONFIG_X86 |
| if (xen_pv_domain()) { |
| if (xen_initial_domain()) |
| pci_xen_initial_domain(); |
| } |
| if (xen_feature(XENFEAT_hvm_callback_vector)) { |
| xen_setup_callback_vector(); |
| xen_alloc_callback_vector(); |
| } |
| |
| if (xen_hvm_domain()) { |
| 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 { |
| int rc; |
| struct physdev_pirq_eoi_gmfn eoi_gmfn; |
| |
| pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO); |
| eoi_gmfn.gmfn = virt_to_gfn(pirq_eoi_map); |
| rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn); |
| if (rc != 0) { |
| free_page((unsigned long) pirq_eoi_map); |
| pirq_eoi_map = NULL; |
| } else |
| pirq_needs_eoi = pirq_check_eoi_map; |
| } |
| #endif |
| } |