| /* |
| * Copyright (C) 2015, 2016 ARM Ltd. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/kvm.h> |
| #include <linux/kvm_host.h> |
| #include <linux/list_sort.h> |
| #include <linux/nospec.h> |
| |
| #include <asm/kvm_hyp.h> |
| |
| #include "vgic.h" |
| |
| #define CREATE_TRACE_POINTS |
| #include "trace.h" |
| |
| struct vgic_global kvm_vgic_global_state __ro_after_init = { |
| .gicv3_cpuif = STATIC_KEY_FALSE_INIT, |
| }; |
| |
| /* |
| * Locking order is always: |
| * kvm->lock (mutex) |
| * its->cmd_lock (mutex) |
| * its->its_lock (mutex) |
| * vgic_cpu->ap_list_lock must be taken with IRQs disabled |
| * kvm->lpi_list_lock must be taken with IRQs disabled |
| * vgic_irq->irq_lock must be taken with IRQs disabled |
| * |
| * As the ap_list_lock might be taken from the timer interrupt handler, |
| * we have to disable IRQs before taking this lock and everything lower |
| * than it. |
| * |
| * If you need to take multiple locks, always take the upper lock first, |
| * then the lower ones, e.g. first take the its_lock, then the irq_lock. |
| * If you are already holding a lock and need to take a higher one, you |
| * have to drop the lower ranking lock first and re-aquire it after having |
| * taken the upper one. |
| * |
| * When taking more than one ap_list_lock at the same time, always take the |
| * lowest numbered VCPU's ap_list_lock first, so: |
| * vcpuX->vcpu_id < vcpuY->vcpu_id: |
| * spin_lock(vcpuX->arch.vgic_cpu.ap_list_lock); |
| * spin_lock(vcpuY->arch.vgic_cpu.ap_list_lock); |
| * |
| * Since the VGIC must support injecting virtual interrupts from ISRs, we have |
| * to use the spin_lock_irqsave/spin_unlock_irqrestore versions of outer |
| * spinlocks for any lock that may be taken while injecting an interrupt. |
| */ |
| |
| /* |
| * Iterate over the VM's list of mapped LPIs to find the one with a |
| * matching interrupt ID and return a reference to the IRQ structure. |
| */ |
| static struct vgic_irq *vgic_get_lpi(struct kvm *kvm, u32 intid) |
| { |
| struct vgic_dist *dist = &kvm->arch.vgic; |
| struct vgic_irq *irq = NULL; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&dist->lpi_list_lock, flags); |
| |
| list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { |
| if (irq->intid != intid) |
| continue; |
| |
| /* |
| * This increases the refcount, the caller is expected to |
| * call vgic_put_irq() later once it's finished with the IRQ. |
| */ |
| vgic_get_irq_kref(irq); |
| goto out_unlock; |
| } |
| irq = NULL; |
| |
| out_unlock: |
| spin_unlock_irqrestore(&dist->lpi_list_lock, flags); |
| |
| return irq; |
| } |
| |
| /* |
| * This looks up the virtual interrupt ID to get the corresponding |
| * struct vgic_irq. It also increases the refcount, so any caller is expected |
| * to call vgic_put_irq() once it's finished with this IRQ. |
| */ |
| struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu, |
| u32 intid) |
| { |
| /* SGIs and PPIs */ |
| if (intid <= VGIC_MAX_PRIVATE) { |
| intid = array_index_nospec(intid, VGIC_MAX_PRIVATE); |
| return &vcpu->arch.vgic_cpu.private_irqs[intid]; |
| } |
| |
| /* SPIs */ |
| if (intid <= VGIC_MAX_SPI) { |
| intid = array_index_nospec(intid, VGIC_MAX_SPI); |
| return &kvm->arch.vgic.spis[intid - VGIC_NR_PRIVATE_IRQS]; |
| } |
| |
| /* LPIs */ |
| if (intid >= VGIC_MIN_LPI) |
| return vgic_get_lpi(kvm, intid); |
| |
| WARN(1, "Looking up struct vgic_irq for reserved INTID"); |
| return NULL; |
| } |
| |
| /* |
| * We can't do anything in here, because we lack the kvm pointer to |
| * lock and remove the item from the lpi_list. So we keep this function |
| * empty and use the return value of kref_put() to trigger the freeing. |
| */ |
| static void vgic_irq_release(struct kref *ref) |
| { |
| } |
| |
| void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq) |
| { |
| struct vgic_dist *dist = &kvm->arch.vgic; |
| unsigned long flags; |
| |
| if (irq->intid < VGIC_MIN_LPI) |
| return; |
| |
| spin_lock_irqsave(&dist->lpi_list_lock, flags); |
| if (!kref_put(&irq->refcount, vgic_irq_release)) { |
| spin_unlock_irqrestore(&dist->lpi_list_lock, flags); |
| return; |
| }; |
| |
| list_del(&irq->lpi_list); |
| dist->lpi_list_count--; |
| spin_unlock_irqrestore(&dist->lpi_list_lock, flags); |
| |
| kfree(irq); |
| } |
| |
| void vgic_irq_set_phys_pending(struct vgic_irq *irq, bool pending) |
| { |
| WARN_ON(irq_set_irqchip_state(irq->host_irq, |
| IRQCHIP_STATE_PENDING, |
| pending)); |
| } |
| |
| bool vgic_get_phys_line_level(struct vgic_irq *irq) |
| { |
| bool line_level; |
| |
| BUG_ON(!irq->hw); |
| |
| if (irq->get_input_level) |
| return irq->get_input_level(irq->intid); |
| |
| WARN_ON(irq_get_irqchip_state(irq->host_irq, |
| IRQCHIP_STATE_PENDING, |
| &line_level)); |
| return line_level; |
| } |
| |
| /* Set/Clear the physical active state */ |
| void vgic_irq_set_phys_active(struct vgic_irq *irq, bool active) |
| { |
| |
| BUG_ON(!irq->hw); |
| WARN_ON(irq_set_irqchip_state(irq->host_irq, |
| IRQCHIP_STATE_ACTIVE, |
| active)); |
| } |
| |
| /** |
| * kvm_vgic_target_oracle - compute the target vcpu for an irq |
| * |
| * @irq: The irq to route. Must be already locked. |
| * |
| * Based on the current state of the interrupt (enabled, pending, |
| * active, vcpu and target_vcpu), compute the next vcpu this should be |
| * given to. Return NULL if this shouldn't be injected at all. |
| * |
| * Requires the IRQ lock to be held. |
| */ |
| static struct kvm_vcpu *vgic_target_oracle(struct vgic_irq *irq) |
| { |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&irq->irq_lock)); |
| |
| /* If the interrupt is active, it must stay on the current vcpu */ |
| if (irq->active) |
| return irq->vcpu ? : irq->target_vcpu; |
| |
| /* |
| * If the IRQ is not active but enabled and pending, we should direct |
| * it to its configured target VCPU. |
| * If the distributor is disabled, pending interrupts shouldn't be |
| * forwarded. |
| */ |
| if (irq->enabled && irq_is_pending(irq)) { |
| if (unlikely(irq->target_vcpu && |
| !irq->target_vcpu->kvm->arch.vgic.enabled)) |
| return NULL; |
| |
| return irq->target_vcpu; |
| } |
| |
| /* If neither active nor pending and enabled, then this IRQ should not |
| * be queued to any VCPU. |
| */ |
| return NULL; |
| } |
| |
| /* |
| * The order of items in the ap_lists defines how we'll pack things in LRs as |
| * well, the first items in the list being the first things populated in the |
| * LRs. |
| * |
| * A hard rule is that active interrupts can never be pushed out of the LRs |
| * (and therefore take priority) since we cannot reliably trap on deactivation |
| * of IRQs and therefore they have to be present in the LRs. |
| * |
| * Otherwise things should be sorted by the priority field and the GIC |
| * hardware support will take care of preemption of priority groups etc. |
| * |
| * Return negative if "a" sorts before "b", 0 to preserve order, and positive |
| * to sort "b" before "a". |
| */ |
| static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b) |
| { |
| struct vgic_irq *irqa = container_of(a, struct vgic_irq, ap_list); |
| struct vgic_irq *irqb = container_of(b, struct vgic_irq, ap_list); |
| bool penda, pendb; |
| int ret; |
| |
| spin_lock(&irqa->irq_lock); |
| spin_lock_nested(&irqb->irq_lock, SINGLE_DEPTH_NESTING); |
| |
| if (irqa->active || irqb->active) { |
| ret = (int)irqb->active - (int)irqa->active; |
| goto out; |
| } |
| |
| penda = irqa->enabled && irq_is_pending(irqa); |
| pendb = irqb->enabled && irq_is_pending(irqb); |
| |
| if (!penda || !pendb) { |
| ret = (int)pendb - (int)penda; |
| goto out; |
| } |
| |
| /* Both pending and enabled, sort by priority */ |
| ret = irqa->priority - irqb->priority; |
| out: |
| spin_unlock(&irqb->irq_lock); |
| spin_unlock(&irqa->irq_lock); |
| return ret; |
| } |
| |
| /* Must be called with the ap_list_lock held */ |
| static void vgic_sort_ap_list(struct kvm_vcpu *vcpu) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&vgic_cpu->ap_list_lock)); |
| |
| list_sort(NULL, &vgic_cpu->ap_list_head, vgic_irq_cmp); |
| } |
| |
| /* |
| * Only valid injection if changing level for level-triggered IRQs or for a |
| * rising edge, and in-kernel connected IRQ lines can only be controlled by |
| * their owner. |
| */ |
| static bool vgic_validate_injection(struct vgic_irq *irq, bool level, void *owner) |
| { |
| if (irq->owner != owner) |
| return false; |
| |
| switch (irq->config) { |
| case VGIC_CONFIG_LEVEL: |
| return irq->line_level != level; |
| case VGIC_CONFIG_EDGE: |
| return level; |
| } |
| |
| return false; |
| } |
| |
| /* |
| * Check whether an IRQ needs to (and can) be queued to a VCPU's ap list. |
| * Do the queuing if necessary, taking the right locks in the right order. |
| * Returns true when the IRQ was queued, false otherwise. |
| * |
| * Needs to be entered with the IRQ lock already held, but will return |
| * with all locks dropped. |
| */ |
| bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq, |
| unsigned long flags) |
| { |
| struct kvm_vcpu *vcpu; |
| |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&irq->irq_lock)); |
| |
| retry: |
| vcpu = vgic_target_oracle(irq); |
| if (irq->vcpu || !vcpu) { |
| /* |
| * If this IRQ is already on a VCPU's ap_list, then it |
| * cannot be moved or modified and there is no more work for |
| * us to do. |
| * |
| * Otherwise, if the irq is not pending and enabled, it does |
| * not need to be inserted into an ap_list and there is also |
| * no more work for us to do. |
| */ |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| |
| /* |
| * We have to kick the VCPU here, because we could be |
| * queueing an edge-triggered interrupt for which we |
| * get no EOI maintenance interrupt. In that case, |
| * while the IRQ is already on the VCPU's AP list, the |
| * VCPU could have EOI'ed the original interrupt and |
| * won't see this one until it exits for some other |
| * reason. |
| */ |
| if (vcpu) { |
| kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); |
| kvm_vcpu_kick(vcpu); |
| } |
| return false; |
| } |
| |
| /* |
| * We must unlock the irq lock to take the ap_list_lock where |
| * we are going to insert this new pending interrupt. |
| */ |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| |
| /* someone can do stuff here, which we re-check below */ |
| |
| spin_lock_irqsave(&vcpu->arch.vgic_cpu.ap_list_lock, flags); |
| spin_lock(&irq->irq_lock); |
| |
| /* |
| * Did something change behind our backs? |
| * |
| * There are two cases: |
| * 1) The irq lost its pending state or was disabled behind our |
| * backs and/or it was queued to another VCPU's ap_list. |
| * 2) Someone changed the affinity on this irq behind our |
| * backs and we are now holding the wrong ap_list_lock. |
| * |
| * In both cases, drop the locks and retry. |
| */ |
| |
| if (unlikely(irq->vcpu || vcpu != vgic_target_oracle(irq))) { |
| spin_unlock(&irq->irq_lock); |
| spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags); |
| |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| goto retry; |
| } |
| |
| /* |
| * Grab a reference to the irq to reflect the fact that it is |
| * now in the ap_list. |
| */ |
| vgic_get_irq_kref(irq); |
| list_add_tail(&irq->ap_list, &vcpu->arch.vgic_cpu.ap_list_head); |
| irq->vcpu = vcpu; |
| |
| spin_unlock(&irq->irq_lock); |
| spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, flags); |
| |
| kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); |
| kvm_vcpu_kick(vcpu); |
| |
| return true; |
| } |
| |
| /** |
| * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic |
| * @kvm: The VM structure pointer |
| * @cpuid: The CPU for PPIs |
| * @intid: The INTID to inject a new state to. |
| * @level: Edge-triggered: true: to trigger the interrupt |
| * false: to ignore the call |
| * Level-sensitive true: raise the input signal |
| * false: lower the input signal |
| * @owner: The opaque pointer to the owner of the IRQ being raised to verify |
| * that the caller is allowed to inject this IRQ. Userspace |
| * injections will have owner == NULL. |
| * |
| * The VGIC is not concerned with devices being active-LOW or active-HIGH for |
| * level-sensitive interrupts. You can think of the level parameter as 1 |
| * being HIGH and 0 being LOW and all devices being active-HIGH. |
| */ |
| int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid, |
| bool level, void *owner) |
| { |
| struct kvm_vcpu *vcpu; |
| struct vgic_irq *irq; |
| unsigned long flags; |
| int ret; |
| |
| trace_vgic_update_irq_pending(cpuid, intid, level); |
| |
| ret = vgic_lazy_init(kvm); |
| if (ret) |
| return ret; |
| |
| vcpu = kvm_get_vcpu(kvm, cpuid); |
| if (!vcpu && intid < VGIC_NR_PRIVATE_IRQS) |
| return -EINVAL; |
| |
| irq = vgic_get_irq(kvm, vcpu, intid); |
| if (!irq) |
| return -EINVAL; |
| |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| |
| if (!vgic_validate_injection(irq, level, owner)) { |
| /* Nothing to see here, move along... */ |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| vgic_put_irq(kvm, irq); |
| return 0; |
| } |
| |
| if (irq->config == VGIC_CONFIG_LEVEL) |
| irq->line_level = level; |
| else |
| irq->pending_latch = true; |
| |
| vgic_queue_irq_unlock(kvm, irq, flags); |
| vgic_put_irq(kvm, irq); |
| |
| return 0; |
| } |
| |
| /* @irq->irq_lock must be held */ |
| static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq, |
| unsigned int host_irq, |
| bool (*get_input_level)(int vindid)) |
| { |
| struct irq_desc *desc; |
| struct irq_data *data; |
| |
| /* |
| * Find the physical IRQ number corresponding to @host_irq |
| */ |
| desc = irq_to_desc(host_irq); |
| if (!desc) { |
| kvm_err("%s: no interrupt descriptor\n", __func__); |
| return -EINVAL; |
| } |
| data = irq_desc_get_irq_data(desc); |
| while (data->parent_data) |
| data = data->parent_data; |
| |
| irq->hw = true; |
| irq->host_irq = host_irq; |
| irq->hwintid = data->hwirq; |
| irq->get_input_level = get_input_level; |
| return 0; |
| } |
| |
| /* @irq->irq_lock must be held */ |
| static inline void kvm_vgic_unmap_irq(struct vgic_irq *irq) |
| { |
| irq->hw = false; |
| irq->hwintid = 0; |
| irq->get_input_level = NULL; |
| } |
| |
| int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq, |
| u32 vintid, bool (*get_input_level)(int vindid)) |
| { |
| struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); |
| unsigned long flags; |
| int ret; |
| |
| BUG_ON(!irq); |
| |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| ret = kvm_vgic_map_irq(vcpu, irq, host_irq, get_input_level); |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| vgic_put_irq(vcpu->kvm, irq); |
| |
| return ret; |
| } |
| |
| /** |
| * kvm_vgic_reset_mapped_irq - Reset a mapped IRQ |
| * @vcpu: The VCPU pointer |
| * @vintid: The INTID of the interrupt |
| * |
| * Reset the active and pending states of a mapped interrupt. Kernel |
| * subsystems injecting mapped interrupts should reset their interrupt lines |
| * when we are doing a reset of the VM. |
| */ |
| void kvm_vgic_reset_mapped_irq(struct kvm_vcpu *vcpu, u32 vintid) |
| { |
| struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); |
| unsigned long flags; |
| |
| if (!irq->hw) |
| goto out; |
| |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| irq->active = false; |
| irq->pending_latch = false; |
| irq->line_level = false; |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| out: |
| vgic_put_irq(vcpu->kvm, irq); |
| } |
| |
| int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid) |
| { |
| struct vgic_irq *irq; |
| unsigned long flags; |
| |
| if (!vgic_initialized(vcpu->kvm)) |
| return -EAGAIN; |
| |
| irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); |
| BUG_ON(!irq); |
| |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| kvm_vgic_unmap_irq(irq); |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| vgic_put_irq(vcpu->kvm, irq); |
| |
| return 0; |
| } |
| |
| /** |
| * kvm_vgic_set_owner - Set the owner of an interrupt for a VM |
| * |
| * @vcpu: Pointer to the VCPU (used for PPIs) |
| * @intid: The virtual INTID identifying the interrupt (PPI or SPI) |
| * @owner: Opaque pointer to the owner |
| * |
| * Returns 0 if intid is not already used by another in-kernel device and the |
| * owner is set, otherwise returns an error code. |
| */ |
| int kvm_vgic_set_owner(struct kvm_vcpu *vcpu, unsigned int intid, void *owner) |
| { |
| struct vgic_irq *irq; |
| unsigned long flags; |
| int ret = 0; |
| |
| if (!vgic_initialized(vcpu->kvm)) |
| return -EAGAIN; |
| |
| /* SGIs and LPIs cannot be wired up to any device */ |
| if (!irq_is_ppi(intid) && !vgic_valid_spi(vcpu->kvm, intid)) |
| return -EINVAL; |
| |
| irq = vgic_get_irq(vcpu->kvm, vcpu, intid); |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| if (irq->owner && irq->owner != owner) |
| ret = -EEXIST; |
| else |
| irq->owner = owner; |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| |
| return ret; |
| } |
| |
| /** |
| * vgic_prune_ap_list - Remove non-relevant interrupts from the list |
| * |
| * @vcpu: The VCPU pointer |
| * |
| * Go over the list of "interesting" interrupts, and prune those that we |
| * won't have to consider in the near future. |
| */ |
| static void vgic_prune_ap_list(struct kvm_vcpu *vcpu) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| struct vgic_irq *irq, *tmp; |
| |
| DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); |
| |
| retry: |
| spin_lock(&vgic_cpu->ap_list_lock); |
| |
| list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) { |
| struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB; |
| bool target_vcpu_needs_kick = false; |
| |
| spin_lock(&irq->irq_lock); |
| |
| BUG_ON(vcpu != irq->vcpu); |
| |
| target_vcpu = vgic_target_oracle(irq); |
| |
| if (!target_vcpu) { |
| /* |
| * We don't need to process this interrupt any |
| * further, move it off the list. |
| */ |
| list_del(&irq->ap_list); |
| irq->vcpu = NULL; |
| spin_unlock(&irq->irq_lock); |
| |
| /* |
| * This vgic_put_irq call matches the |
| * vgic_get_irq_kref in vgic_queue_irq_unlock, |
| * where we added the LPI to the ap_list. As |
| * we remove the irq from the list, we drop |
| * also drop the refcount. |
| */ |
| vgic_put_irq(vcpu->kvm, irq); |
| continue; |
| } |
| |
| if (target_vcpu == vcpu) { |
| /* We're on the right CPU */ |
| spin_unlock(&irq->irq_lock); |
| continue; |
| } |
| |
| /* This interrupt looks like it has to be migrated. */ |
| |
| spin_unlock(&irq->irq_lock); |
| spin_unlock(&vgic_cpu->ap_list_lock); |
| |
| /* |
| * Ensure locking order by always locking the smallest |
| * ID first. |
| */ |
| if (vcpu->vcpu_id < target_vcpu->vcpu_id) { |
| vcpuA = vcpu; |
| vcpuB = target_vcpu; |
| } else { |
| vcpuA = target_vcpu; |
| vcpuB = vcpu; |
| } |
| |
| spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock); |
| spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock, |
| SINGLE_DEPTH_NESTING); |
| spin_lock(&irq->irq_lock); |
| |
| /* |
| * If the affinity has been preserved, move the |
| * interrupt around. Otherwise, it means things have |
| * changed while the interrupt was unlocked, and we |
| * need to replay this. |
| * |
| * In all cases, we cannot trust the list not to have |
| * changed, so we restart from the beginning. |
| */ |
| if (target_vcpu == vgic_target_oracle(irq)) { |
| struct vgic_cpu *new_cpu = &target_vcpu->arch.vgic_cpu; |
| |
| list_del(&irq->ap_list); |
| irq->vcpu = target_vcpu; |
| list_add_tail(&irq->ap_list, &new_cpu->ap_list_head); |
| target_vcpu_needs_kick = true; |
| } |
| |
| spin_unlock(&irq->irq_lock); |
| spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock); |
| spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock); |
| |
| if (target_vcpu_needs_kick) { |
| kvm_make_request(KVM_REQ_IRQ_PENDING, target_vcpu); |
| kvm_vcpu_kick(target_vcpu); |
| } |
| |
| goto retry; |
| } |
| |
| spin_unlock(&vgic_cpu->ap_list_lock); |
| } |
| |
| static inline void vgic_fold_lr_state(struct kvm_vcpu *vcpu) |
| { |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_fold_lr_state(vcpu); |
| else |
| vgic_v3_fold_lr_state(vcpu); |
| } |
| |
| /* Requires the irq_lock to be held. */ |
| static inline void vgic_populate_lr(struct kvm_vcpu *vcpu, |
| struct vgic_irq *irq, int lr) |
| { |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&irq->irq_lock)); |
| |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_populate_lr(vcpu, irq, lr); |
| else |
| vgic_v3_populate_lr(vcpu, irq, lr); |
| } |
| |
| static inline void vgic_clear_lr(struct kvm_vcpu *vcpu, int lr) |
| { |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_clear_lr(vcpu, lr); |
| else |
| vgic_v3_clear_lr(vcpu, lr); |
| } |
| |
| static inline void vgic_set_underflow(struct kvm_vcpu *vcpu) |
| { |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_set_underflow(vcpu); |
| else |
| vgic_v3_set_underflow(vcpu); |
| } |
| |
| /* Requires the ap_list_lock to be held. */ |
| static int compute_ap_list_depth(struct kvm_vcpu *vcpu, |
| bool *multi_sgi) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| struct vgic_irq *irq; |
| int count = 0; |
| |
| *multi_sgi = false; |
| |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&vgic_cpu->ap_list_lock)); |
| |
| list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { |
| int w; |
| |
| spin_lock(&irq->irq_lock); |
| /* GICv2 SGIs can count for more than one... */ |
| w = vgic_irq_get_lr_count(irq); |
| spin_unlock(&irq->irq_lock); |
| |
| count += w; |
| *multi_sgi |= (w > 1); |
| } |
| return count; |
| } |
| |
| /* Requires the VCPU's ap_list_lock to be held. */ |
| static void vgic_flush_lr_state(struct kvm_vcpu *vcpu) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| struct vgic_irq *irq; |
| int count; |
| bool multi_sgi; |
| u8 prio = 0xff; |
| |
| DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&vgic_cpu->ap_list_lock)); |
| |
| count = compute_ap_list_depth(vcpu, &multi_sgi); |
| if (count > kvm_vgic_global_state.nr_lr || multi_sgi) |
| vgic_sort_ap_list(vcpu); |
| |
| count = 0; |
| |
| list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { |
| spin_lock(&irq->irq_lock); |
| |
| /* |
| * If we have multi-SGIs in the pipeline, we need to |
| * guarantee that they are all seen before any IRQ of |
| * lower priority. In that case, we need to filter out |
| * these interrupts by exiting early. This is easy as |
| * the AP list has been sorted already. |
| */ |
| if (multi_sgi && irq->priority > prio) { |
| spin_unlock(&irq->irq_lock); |
| break; |
| } |
| |
| if (likely(vgic_target_oracle(irq) == vcpu)) { |
| vgic_populate_lr(vcpu, irq, count++); |
| |
| if (irq->source) |
| prio = irq->priority; |
| } |
| |
| spin_unlock(&irq->irq_lock); |
| |
| if (count == kvm_vgic_global_state.nr_lr) { |
| if (!list_is_last(&irq->ap_list, |
| &vgic_cpu->ap_list_head)) |
| vgic_set_underflow(vcpu); |
| break; |
| } |
| } |
| |
| vcpu->arch.vgic_cpu.used_lrs = count; |
| |
| /* Nuke remaining LRs */ |
| for ( ; count < kvm_vgic_global_state.nr_lr; count++) |
| vgic_clear_lr(vcpu, count); |
| } |
| |
| static inline bool can_access_vgic_from_kernel(void) |
| { |
| /* |
| * GICv2 can always be accessed from the kernel because it is |
| * memory-mapped, and VHE systems can access GICv3 EL2 system |
| * registers. |
| */ |
| return !static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif) || has_vhe(); |
| } |
| |
| static inline void vgic_save_state(struct kvm_vcpu *vcpu) |
| { |
| if (!static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) |
| vgic_v2_save_state(vcpu); |
| else |
| __vgic_v3_save_state(vcpu); |
| } |
| |
| /* Sync back the hardware VGIC state into our emulation after a guest's run. */ |
| void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| |
| WARN_ON(vgic_v4_sync_hwstate(vcpu)); |
| |
| /* An empty ap_list_head implies used_lrs == 0 */ |
| if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head)) |
| return; |
| |
| if (can_access_vgic_from_kernel()) |
| vgic_save_state(vcpu); |
| |
| if (vgic_cpu->used_lrs) |
| vgic_fold_lr_state(vcpu); |
| vgic_prune_ap_list(vcpu); |
| } |
| |
| static inline void vgic_restore_state(struct kvm_vcpu *vcpu) |
| { |
| if (!static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) |
| vgic_v2_restore_state(vcpu); |
| else |
| __vgic_v3_restore_state(vcpu); |
| } |
| |
| /* Flush our emulation state into the GIC hardware before entering the guest. */ |
| void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) |
| { |
| WARN_ON(vgic_v4_flush_hwstate(vcpu)); |
| |
| /* |
| * If there are no virtual interrupts active or pending for this |
| * VCPU, then there is no work to do and we can bail out without |
| * taking any lock. There is a potential race with someone injecting |
| * interrupts to the VCPU, but it is a benign race as the VCPU will |
| * either observe the new interrupt before or after doing this check, |
| * and introducing additional synchronization mechanism doesn't change |
| * this. |
| */ |
| if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head)) |
| return; |
| |
| DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); |
| |
| spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); |
| vgic_flush_lr_state(vcpu); |
| spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); |
| |
| if (can_access_vgic_from_kernel()) |
| vgic_restore_state(vcpu); |
| } |
| |
| void kvm_vgic_load(struct kvm_vcpu *vcpu) |
| { |
| if (unlikely(!vgic_initialized(vcpu->kvm))) |
| return; |
| |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_load(vcpu); |
| else |
| vgic_v3_load(vcpu); |
| } |
| |
| void kvm_vgic_put(struct kvm_vcpu *vcpu) |
| { |
| if (unlikely(!vgic_initialized(vcpu->kvm))) |
| return; |
| |
| if (kvm_vgic_global_state.type == VGIC_V2) |
| vgic_v2_put(vcpu); |
| else |
| vgic_v3_put(vcpu); |
| } |
| |
| int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) |
| { |
| struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; |
| struct vgic_irq *irq; |
| bool pending = false; |
| unsigned long flags; |
| |
| if (!vcpu->kvm->arch.vgic.enabled) |
| return false; |
| |
| if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last) |
| return true; |
| |
| spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags); |
| |
| list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { |
| spin_lock(&irq->irq_lock); |
| pending = irq_is_pending(irq) && irq->enabled; |
| spin_unlock(&irq->irq_lock); |
| |
| if (pending) |
| break; |
| } |
| |
| spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags); |
| |
| return pending; |
| } |
| |
| void vgic_kick_vcpus(struct kvm *kvm) |
| { |
| struct kvm_vcpu *vcpu; |
| int c; |
| |
| /* |
| * We've injected an interrupt, time to find out who deserves |
| * a good kick... |
| */ |
| kvm_for_each_vcpu(c, vcpu, kvm) { |
| if (kvm_vgic_vcpu_pending_irq(vcpu)) { |
| kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); |
| kvm_vcpu_kick(vcpu); |
| } |
| } |
| } |
| |
| bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid) |
| { |
| struct vgic_irq *irq; |
| bool map_is_active; |
| unsigned long flags; |
| |
| if (!vgic_initialized(vcpu->kvm)) |
| return false; |
| |
| irq = vgic_get_irq(vcpu->kvm, vcpu, vintid); |
| spin_lock_irqsave(&irq->irq_lock, flags); |
| map_is_active = irq->hw && irq->active; |
| spin_unlock_irqrestore(&irq->irq_lock, flags); |
| vgic_put_irq(vcpu->kvm, irq); |
| |
| return map_is_active; |
| } |
| |