mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1023 lines
26 KiB
1023 lines
26 KiB
// 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; |
|
int i = 0; |
|
|
|
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; |
|
} |
|
} |
|
|
|
/* Nuke remaining LRs */ |
|
for (i = count ; i < kvm_vgic_global_state.nr_lr; i++) |
|
vgic_clear_lr(vcpu, i); |
|
|
|
if (!static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) |
|
vcpu->arch.vgic_cpu.vgic_v2.used_lrs = count; |
|
else |
|
vcpu->arch.vgic_cpu.vgic_v3.used_lrs = 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->arch.vgic_cpu.vgic_v3); |
|
} |
|
|
|
/* Sync back the hardware VGIC state into our emulation after a guest's run. */ |
|
void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) |
|
{ |
|
int used_lrs; |
|
|
|
/* 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 (!static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) |
|
used_lrs = vcpu->arch.vgic_cpu.vgic_v2.used_lrs; |
|
else |
|
used_lrs = vcpu->arch.vgic_cpu.vgic_v3.used_lrs; |
|
|
|
if (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->arch.vgic_cpu.vgic_v3); |
|
} |
|
|
|
/* 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); |
|
|
|
if (vgic_supports_direct_msis(vcpu->kvm)) |
|
vgic_v4_commit(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; |
|
}
|
|
|