diff options
Diffstat (limited to 'virt/kvm/arm/vgic/vgic.c')
| -rw-r--r-- | virt/kvm/arm/vgic/vgic.c | 1011 |
1 files changed, 0 insertions, 1011 deletions
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c deleted file mode 100644 index 99b02ca730a8..000000000000 --- a/virt/kvm/arm/vgic/vgic.c +++ /dev/null @@ -1,1011 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2015, 2016 ARM Ltd. - */ - -#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: - * raw_spin_lock(vcpuX->arch.vgic_cpu.ap_list_lock); - * raw_spin_lock(vcpuY->arch.vgic_cpu.ap_list_lock); - * - * Since the VGIC must support injecting virtual interrupts from ISRs, we have - * to use the raw_spin_lock_irqsave/raw_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; - - raw_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: - raw_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 + 1); - return &vcpu->arch.vgic_cpu.private_irqs[intid]; - } - - /* SPIs */ - if (intid < (kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS)) { - intid = array_index_nospec(intid, kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS); - 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) -{ -} - -/* - * Drop the refcount on the LPI. Must be called with lpi_list_lock held. - */ -void __vgic_put_lpi_locked(struct kvm *kvm, struct vgic_irq *irq) -{ - struct vgic_dist *dist = &kvm->arch.vgic; - - if (!kref_put(&irq->refcount, vgic_irq_release)) - return; - - list_del(&irq->lpi_list); - dist->lpi_list_count--; - - kfree(irq); -} - -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; - - raw_spin_lock_irqsave(&dist->lpi_list_lock, flags); - __vgic_put_lpi_locked(kvm, irq); - raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); -} - -void vgic_flush_pending_lpis(struct kvm_vcpu *vcpu) -{ - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; - struct vgic_irq *irq, *tmp; - unsigned long flags; - - raw_spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags); - - list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) { - if (irq->intid >= VGIC_MIN_LPI) { - raw_spin_lock(&irq->irq_lock); - list_del(&irq->ap_list); - irq->vcpu = NULL; - raw_spin_unlock(&irq->irq_lock); - vgic_put_irq(vcpu->kvm, irq); - } - } - - raw_spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags); -} - -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) -{ - lockdep_assert_held(&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; - - /* - * list_sort may call this function with the same element when - * the list is fairly long. - */ - if (unlikely(irqa == irqb)) - return 0; - - raw_spin_lock(&irqa->irq_lock); - raw_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: - raw_spin_unlock(&irqb->irq_lock); - raw_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; - - lockdep_assert_held(&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; - - lockdep_assert_held(&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. - */ - raw_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. - */ - raw_spin_unlock_irqrestore(&irq->irq_lock, flags); - - /* someone can do stuff here, which we re-check below */ - - raw_spin_lock_irqsave(&vcpu->arch.vgic_cpu.ap_list_lock, flags); - raw_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))) { - raw_spin_unlock(&irq->irq_lock); - raw_spin_unlock_irqrestore(&vcpu->arch.vgic_cpu.ap_list_lock, - flags); - - raw_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; - - raw_spin_unlock(&irq->irq_lock); - raw_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; - - raw_spin_lock_irqsave(&irq->irq_lock, flags); - - if (!vgic_validate_injection(irq, level, owner)) { - /* Nothing to see here, move along... */ - raw_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); - - raw_spin_lock_irqsave(&irq->irq_lock, flags); - ret = kvm_vgic_map_irq(vcpu, irq, host_irq, get_input_level); - raw_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; - - raw_spin_lock_irqsave(&irq->irq_lock, flags); - irq->active = false; - irq->pending_latch = false; - irq->line_level = false; - raw_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); - - raw_spin_lock_irqsave(&irq->irq_lock, flags); - kvm_vgic_unmap_irq(irq); - raw_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); - raw_spin_lock_irqsave(&irq->irq_lock, flags); - if (irq->owner && irq->owner != owner) - ret = -EEXIST; - else - irq->owner = owner; - raw_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: - raw_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; - - raw_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; - raw_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 */ - raw_spin_unlock(&irq->irq_lock); - continue; - } - - /* This interrupt looks like it has to be migrated. */ - - raw_spin_unlock(&irq->irq_lock); - raw_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; - } - - raw_spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock); - raw_spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock, - SINGLE_DEPTH_NESTING); - raw_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; - } - - raw_spin_unlock(&irq->irq_lock); - raw_spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock); - raw_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; - } - - raw_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) -{ - lockdep_assert_held(&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; - - lockdep_assert_held(&vgic_cpu->ap_list_lock); - - list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { - int w; - - raw_spin_lock(&irq->irq_lock); - /* GICv2 SGIs can count for more than one... */ - w = vgic_irq_get_lr_count(irq); - raw_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; - - lockdep_assert_held(&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) { - raw_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) { - _raw_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; - } - - raw_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; - - /* 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) -{ - /* - * 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. - * - * Note that we still need to go through the whole thing if anything - * can be directly injected (GICv4). - */ - if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head) && - !vgic_supports_direct_msis(vcpu->kvm)) - return; - - DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); - - if (!list_empty(&vcpu->arch.vgic_cpu.ap_list_head)) { - raw_spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); - vgic_flush_lr_state(vcpu); - raw_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); -} - -void kvm_vgic_vmcr_sync(struct kvm_vcpu *vcpu) -{ - if (unlikely(!irqchip_in_kernel(vcpu->kvm))) - return; - - if (kvm_vgic_global_state.type == VGIC_V2) - vgic_v2_vmcr_sync(vcpu); - else - vgic_v3_vmcr_sync(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; - struct vgic_vmcr vmcr; - - if (!vcpu->kvm->arch.vgic.enabled) - return false; - - if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last) - return true; - - vgic_get_vmcr(vcpu, &vmcr); - - raw_spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags); - - list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) { - raw_spin_lock(&irq->irq_lock); - pending = irq_is_pending(irq) && irq->enabled && - !irq->active && - irq->priority < vmcr.pmr; - raw_spin_unlock(&irq->irq_lock); - - if (pending) - break; - } - - raw_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); - raw_spin_lock_irqsave(&irq->irq_lock, flags); - map_is_active = irq->hw && irq->active; - raw_spin_unlock_irqrestore(&irq->irq_lock, flags); - vgic_put_irq(vcpu->kvm, irq); - - return map_is_active; -} |