The LPI pending status for a GICv3 redistributor is held in a table in (guest) memory. To achieve reasonable performance, we cache this data in our struct vgic_irq. The initial pending state must be read from guest memory upon enabling LPIs for this redistributor.
Signed-off-by: Andre Przywara <[email protected]> --- virt/kvm/arm/vgic/vgic-its.c | 43 +++++++++++++++++++++++++++++++++++++++++++ virt/kvm/arm/vgic/vgic.h | 6 ++++++ 2 files changed, 49 insertions(+) diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 9ef951f7..ba2af85 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -149,6 +149,43 @@ struct its_itte { #define CBASER_ADDRESS(x) ((x) & GENMASK_ULL(51, 12)) #define BASER_ADDRESS(x) ((x) & GENMASK_ULL(47, 12)) +#define PENDBASER_ADDRESS(x) ((x) & GENMASK_ULL(51, 16)) + +/* + * Scan the whole LPI pending table and sync the pending bit in there + * with our own data structures. This relies on the LPI being + * mapped before. + */ +static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) +{ + gpa_t pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; + struct vgic_irq *irq; + u8 pendmask; + int ret = 0; + + mutex_lock(&dist->lpi_list_lock); + list_for_each_entry(irq, &dist->lpi_list_head, lpi_entry) { + int byte_offset, bit_nr; + + byte_offset = irq->intid / BITS_PER_BYTE; + bit_nr = irq->intid % BITS_PER_BYTE; + + ret = kvm_read_guest(vcpu->kvm, pendbase + byte_offset, + &pendmask, 1); + if (ret) + goto out_unlock; + + spin_lock(&irq->irq_lock); + irq->pending = pendmask & (1U << bit_nr); + vgic_queue_irq_put(vcpu->kvm, irq); + } + +out_unlock: + mutex_unlock(&dist->lpi_list_lock); + + return ret; +} #define ITS_FRAME(addr) ((addr) & ~(SZ_64K - 1)) @@ -454,6 +491,12 @@ struct vgic_register_region its_registers[] = { VGIC_ACCESS_32bit), }; +/* This is called on setting the LPI enable bit in the redistributor. */ +void vgic_enable_lpis(struct kvm_vcpu *vcpu) +{ + its_sync_lpi_pending_table(vcpu); +} + static int vits_register(struct kvm *kvm, struct vgic_its *its) { struct vgic_io_device *iodev = &its->iodev; diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h index 558252d..8c2105a 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -25,6 +25,7 @@ #define IS_VGIC_ADDR_UNDEF(_x) ((_x) == VGIC_ADDR_UNDEF) #define INTERRUPT_ID_BITS_SPIS 10 +#define INTERRUPT_ID_BITS_ITS 16 #define VGIC_PRI_BITS 5 #define vgic_irq_is_sgi(intid) ((intid) < VGIC_NR_SGIS) @@ -82,6 +83,7 @@ int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address); bool vgic_has_its(struct kvm *kvm); int kvm_vgic_register_its_device(void); struct vgic_irq *vgic_its_get_lpi(struct kvm *kvm, u32 intid); +void vgic_enable_lpis(struct kvm_vcpu *vcpu); #else static inline void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu) { @@ -148,6 +150,10 @@ static inline struct vgic_irq *vgic_its_get_lpi(struct kvm *kvm, u32 intid) { return NULL; } + +static inline void vgic_enable_lpis(struct kvm_vcpu *vcpu) +{ +} #endif int kvm_register_vgic_device(unsigned long type); -- 2.8.2 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
