On Mon, Sep 01, 2014 at 10:53:04AM +0200, Eric Auger wrote: > This patch enables irqfd on ARM. > > irqfd framework enables to inject a virtual IRQ into a guest upon an > eventfd trigger. User-side uses KVM_IRQFD VM ioctl to provide KVM with > a kvm_irqfd struct that associates a VM, an eventfd, a virtual IRQ number > (aka. the gsi). When an actor signals the eventfd (typically a VFIO > platform driver), the kvm irqfd subsystem injects the provided virtual > IRQ into the guest. > > Resamplefd also is supported for level sensitive interrupts, ie. the > user can provide another eventfd that is triggered when the completion > of the virtual IRQ (gsi) is detected by the GIC. > > The gsi must correspond to a shared peripheral interrupt (SPI), ie the > GIC interrupt ID is gsi+32. > > this patch enables CONFIG_HAVE_KVM_EVENTFD and CONFIG_HAVE_KVM_IRQFD. > CONFIG_HAVE_KVM_IRQCHIP is removed. No IRQ routing table is used > (irqchip.c and irqcomm.c are not used). > > Both KVM_CAP_IRQFD & KVM_CAP_IRQFD_RESAMPLE capabilities are exposed > > Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > > --- > > This patch serie deprecates the previous serie featuring GSI routing > (https://patches.linaro.org/32261/) > > The patch serie has the following dependencies: > - arm/arm64: KVM: Various VGIC cleanups and improvements > https://lists.cs.columbia.edu/pipermail/kvmarm/2014-June/009979.html > - "KVM: EVENTFD: remove inclusion of irq.h" > > All pieces can be found on git://git.linaro.org/people/eric.auger/linux.git > branch irqfd_norouting_integ_v3 > > This work was tested with Calxeda Midway xgmac main interrupt with > qemu-system-arm and QEMU VFIO platform device. > > v2 -> v3: > - removal of irq.h from eventfd.c put in a separate patch to increase > visibility > - properly expose KVM_CAP_IRQFD capability in arm.c > - remove CONFIG_HAVE_KVM_IRQCHIP meaningfull only if irq_comm.c is used > > v1 -> v2: > - rebase on 3.17rc1 > - move of the dist unlock in process_maintenance > - remove of dist lock in __kvm_vgic_sync_hwstate > - rewording of the commit message (add resamplefd reference) > - remove irq.h > --- > Documentation/virtual/kvm/api.txt | 5 +++- > arch/arm/include/uapi/asm/kvm.h | 3 +++ > arch/arm/kvm/Kconfig | 4 +-- > arch/arm/kvm/Makefile | 2 +- > arch/arm/kvm/arm.c | 3 +++ > virt/kvm/arm/vgic.c | 56 ++++++++++++++++++++++++++++++++++++--- > 6 files changed, 65 insertions(+), 8 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index beae3fd..8118b12 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -2204,7 +2204,7 @@ into the hash PTE second double word). > 4.75 KVM_IRQFD > > Capability: KVM_CAP_IRQFD > -Architectures: x86 s390 > +Architectures: x86 s390 arm > Type: vm ioctl > Parameters: struct kvm_irqfd (in) > Returns: 0 on success, -1 on error > @@ -2230,6 +2230,9 @@ Note that closing the resamplefd is not sufficient to disable the > irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment > and need not be specified with KVM_IRQFD_FLAG_DEASSIGN. > > +On ARM/arm64 the injected must be a shared peripheral interrupt (SPI). > +This means the programmed GIC interrupt ID is gsi+32. > + See above comment. > 4.76 KVM_PPC_ALLOCATE_HTAB > > Capability: KVM_CAP_PPC_ALLOC_HTAB > diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h > index e6ebdd3..3034c66 100644 > --- a/arch/arm/include/uapi/asm/kvm.h > +++ b/arch/arm/include/uapi/asm/kvm.h > @@ -194,6 +194,9 @@ struct kvm_arch_memory_slot { > /* Highest supported SPI, from VGIC_NR_IRQS */ > #define KVM_ARM_IRQ_GIC_MAX 127 > > +/* One single KVM irqchip, ie. the VGIC */ > +#define KVM_NR_IRQCHIPS 1 > + > /* PSCI interface */ > #define KVM_PSCI_FN_BASE 0x95c1ba5e > #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) > diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig > index 466bd29..e519a40 100644 > --- a/arch/arm/kvm/Kconfig > +++ b/arch/arm/kvm/Kconfig > @@ -24,6 +24,7 @@ config KVM > select KVM_MMIO > select KVM_ARM_HOST > depends on ARM_VIRT_EXT && ARM_LPAE > + select HAVE_KVM_EVENTFD > ---help--- > Support hosting virtualized guest machines. You will also > need to select one or more of the processor modules below. > @@ -55,7 +56,7 @@ config KVM_ARM_MAX_VCPUS > config KVM_ARM_VGIC > bool "KVM support for Virtual GIC" > depends on KVM_ARM_HOST && OF > - select HAVE_KVM_IRQCHIP > + select HAVE_KVM_IRQFD > default y > ---help--- > Adds support for a hardware assisted, in-kernel GIC emulation. > @@ -63,7 +64,6 @@ config KVM_ARM_VGIC > config KVM_ARM_TIMER > bool "KVM support for Architected Timers" > depends on KVM_ARM_VGIC && ARM_ARCH_TIMER > - select HAVE_KVM_IRQCHIP > default y > ---help--- > Adds support for the Architected Timers in virtual machines > diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile > index f7057ed..859db09 100644 > --- a/arch/arm/kvm/Makefile > +++ b/arch/arm/kvm/Makefile > @@ -15,7 +15,7 @@ AFLAGS_init.o := -Wa,-march=armv7-a$(plus_virt) > AFLAGS_interrupts.o := -Wa,-march=armv7-a$(plus_virt) > > KVM := ../../../virt/kvm > -kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o > +kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o > > obj-y += kvm-arm.o init.o interrupts.o > obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o > diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c > index a99e0cd..6ba454a 100644 > --- a/arch/arm/kvm/arm.c > +++ b/arch/arm/kvm/arm.c > @@ -181,6 +181,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > case KVM_CAP_IRQCHIP: > r = vgic_present; > break; > +#ifdef CONFIG_HAVE_KVM_IRQFD > + case KVM_CAP_IRQFD: > +#endif > case KVM_CAP_DEVICE_CTRL: > case KVM_CAP_USER_MEMORY: > case KVM_CAP_SYNC_MMU: > diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c > index 7164d2e..586bd11 100644 > --- a/virt/kvm/arm/vgic.c > +++ b/virt/kvm/arm/vgic.c > @@ -1334,7 +1334,10 @@ epilog: > static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) > { > u32 status = vgic_get_interrupt_status(vcpu); > + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; > bool level_pending = false; > + struct kvm *kvm = vcpu->kvm; > + int is_assigned_irq; > > kvm_debug("STATUS = %08x\n", status); > > @@ -1351,6 +1354,7 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) > struct vgic_lr vlr = vgic_get_lr(vcpu, lr); > BUG_ON(vgic_irq_is_edge(vcpu, vlr.irq)); > > + spin_lock(&dist->lock); > vgic_irq_clear_queued(vcpu, vlr.irq); > WARN_ON(vlr.state & LR_STATE_MASK); > vlr.state = 0; > @@ -1363,6 +1367,18 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) > * interrupt. > */ > vgic_dist_irq_clear_soft_pend(vcpu, vlr.irq); > + spin_unlock(&dist->lock); may be worth a small comment saying that we unlock the distributor lock to allow kvm_notify_acked_irq() to come back to injecting an IRQ which grabs the dist->lock again. > + > + is_assigned_irq = kvm_irq_has_notifier(kvm, 0, > + vlr.irq - VGIC_NR_PRIVATE_IRQS); is is_assigned_irq really accurately describing the state you are determining here? Can't you have an irqfd without a resamplefd, or did I get this wrong? In any case, this code may be simpler if you simply inline the call to kvm_irq_has_notifier or name the variable 'irq_has_notifier'. > + > + if (is_assigned_irq) { > + kvm_debug("EOI irqchip routed vIRQ %d\n", > + vlr.irq); EOI irqchip routed vIRQ X? -ECANTPARSE, how about "Guest EOIed vIRQ %d on CPU %d\n" ? > + kvm_notify_acked_irq(kvm, 0, > + vlr.irq - VGIC_NR_PRIVATE_IRQS); > + } > + spin_lock(&dist->lock); > > /* Any additional pending interrupt? */ > if (vgic_dist_irq_get_level(vcpu, vlr.irq)) { > @@ -1377,6 +1393,8 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) > vgic_cpu_irq_clear(vcpu, vlr.irq); > } > > + spin_unlock(&dist->lock); > + > /* > * Despite being EOIed, the LR may not have > * been marked as empty. > @@ -1441,14 +1459,10 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) > > void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) > { > - struct vgic_dist *dist = &vcpu->kvm->arch.vgic; > - > if (!irqchip_in_kernel(vcpu->kvm)) > return; > > - spin_lock(&dist->lock); > __kvm_vgic_sync_hwstate(vcpu); > - spin_unlock(&dist->lock); > } > > int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) > @@ -2183,3 +2197,37 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = { > .get_attr = vgic_get_attr, > .has_attr = vgic_has_attr, > }; > + > +int kvm_irq_map_gsi(struct kvm *kvm, > + struct kvm_kernel_irq_routing_entry *entries, > + int gsi) > +{ > + return gsi; > +} > + > +int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin) > +{ > + return pin; > +} > + > +int kvm_set_irq(struct kvm *kvm, int irq_source_id, > + u32 irq, int level, bool line_status) what does line_status indicate? > +{ > + int r = -EINVAL; > + unsigned int spi = irq + VGIC_NR_PRIVATE_IRQS; > + > + if (spi > KVM_ARM_IRQ_GIC_MAX) > + return r; can you just do 'return -EINVAL' here and not initialize r above. > + > + kvm_debug("Inject irqchip routed vIRQ %d\n", irq); > + r = kvm_vgic_inject_irq(kvm, 0, spi, level); > + return r; > +} > + > +/* MSI not implemented yet */ > +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, > + struct kvm *kvm, int irq_source_id, > + int level, bool line_status) > +{ > + return 0; > +} > -- > 1.9.1 > Besides the cosmetics and the missing PPI support, this is looking good! Thanks, -Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
