[PATCH v3 4/7] KVM: arm/arm64: enable irqchip routing
From: Eric Auger
Date: Mon Aug 03 2015 - 11:33:45 EST
This patch adds compilation and link against irqchip.
On ARM, irqchip routing is not really useful since there is
a single irqchip. However main motivation behind using irqchip
code is to enable MSI routing code. With the support of in-kernel
GICv3 ITS emulation, it now seems to be a MUST HAVE requirement.
Functions previously implemented in vgic.c and substitute
to more complex irqchip implementation are removed:
- kvm_send_userspace_msi
- kvm_irq_map_chip_pin
- kvm_set_irq
- kvm_irq_map_gsi.
Routing standard hooks are now implemented in vgic:
- kvm_set_routing_entry
- kvm_set_irq
- kvm_set_msi
Both HAVE_KVM_IRQCHIP and HAVE_KVM_IRQ_ROUTING are defined.
KVM_CAP_IRQ_ROUTING is advertised and KVM_SET_GSI_ROUTING is allowed.
MSI routing setup is not yet allowed.
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
v2 -> v3:
- unconditionally set devid and KVM_MSI_VALID_DEVID flag as suggested
by Andre (KVM_IRQ_ROUTING_EXTENDED_MSI type not used anymore)
- vgic_irqfd_set_irq now is static
- propagate flags
- add comments
v1 -> v2:
- fix bug reported by Andre related to msi.flags and msi.devid setting
in kvm_send_userspace_msi
- avoid injecting reserved IRQ numbers in vgic_irqfd_set_irq
RFC -> PATCH
- reword api.txt:
x move MSI routing comments in a subsequent patch,
x clearly state GSI routing does not apply to KVM_IRQ_LINE
Conflicts:
include/kvm/arm_vgic.h
virt/kvm/arm/vgic.c
---
Documentation/virtual/kvm/api.txt | 12 ++++--
arch/arm/include/asm/kvm_host.h | 2 +
arch/arm/kvm/Kconfig | 2 +
arch/arm/kvm/Makefile | 2 +-
arch/arm64/include/asm/kvm_host.h | 1 +
arch/arm64/kvm/Kconfig | 2 +
arch/arm64/kvm/Makefile | 2 +-
include/kvm/arm_vgic.h | 2 -
virt/kvm/arm/vgic.c | 82 ++++++++++++++++++++++++++++-----------
virt/kvm/irqchip.c | 2 +
10 files changed, 78 insertions(+), 31 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index d4b29df..b6913c9 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1421,13 +1421,16 @@ KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed.
4.52 KVM_SET_GSI_ROUTING
Capability: KVM_CAP_IRQ_ROUTING
-Architectures: x86 s390
+Architectures: x86 s390 arm arm64
Type: vm ioctl
Parameters: struct kvm_irq_routing (in)
Returns: 0 on success, -1 on error
Sets the GSI routing table entries, overwriting any previously set entries.
+On arm/arm64, GSI routing has the following limitation:
+- GSI routing does not apply to KVM_IRQ_LINE but only to KVM_IRQFD.
+
struct kvm_irq_routing {
__u32 nr;
__u32 flags;
@@ -2345,9 +2348,10 @@ 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 gsi field in the kvm_irqfd struct specifies the Shared
-Peripheral Interrupt (SPI) index, such that the GIC interrupt ID is
-given by gsi + 32.
+On arm/arm64, gsi routing being supported, the following can happen:
+- in case no routing entry is associated to this gsi, injection fails
+- in case the gsi is associated to an irqchip routing entry,
+ irqchip.pin + 32 corresponds to the injected SPI ID.
4.76 KVM_PPC_ALLOCATE_HTAB
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 56cac05..8a68e9e 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -42,6 +42,8 @@
#define KVM_VCPU_MAX_FEATURES 2
+#define KVM_IRQCHIP_NUM_PINS 988 /* 1020 - 32 is the number of SPI */
+
#include <kvm/arm_vgic.h>
u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index bfb915d..151e710 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -31,6 +31,8 @@ config KVM
select KVM_VFIO
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
+ select HAVE_KVM_IRQCHIP
+ select HAVE_KVM_IRQ_ROUTING
depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER
---help---
Support hosting virtualized guest machines.
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index c5eef02c..1a8f48a 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)/eventfd.o $(KVM)/vfio.o
+kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o $(KVM)/irqchip.o
obj-y += kvm-arm.o init.o interrupts.o
obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 8d78a72..38a3291 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -44,6 +44,7 @@
#include <kvm/arm_arch_timer.h>
#define KVM_VCPU_MAX_FEATURES 3
+#define KVM_IRQCHIP_NUM_PINS 988 /* 1020 - 32 is the number of SPI */
int __attribute_const__ kvm_target_cpu(void);
int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index ff9722f..1a9900d 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -32,6 +32,8 @@ config KVM
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
select HAVE_KVM_MSI
+ select HAVE_KVM_IRQCHIP
+ select HAVE_KVM_IRQ_ROUTING
---help---
Support hosting virtualized guest machines.
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index 9803307..90a08457 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -11,7 +11,7 @@ ARM=../../../arch/arm/kvm
obj-$(CONFIG_KVM_ARM_HOST) += kvm.o
-kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o
+kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o $(KVM)/irqchip.o
kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/arm.o $(ARM)/mmu.o $(ARM)/mmio.o
kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index f50081c..1b370a0 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -375,6 +375,4 @@ static inline int vgic_v3_probe(struct device_node *vgic_node,
}
#endif
-int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi);
-
#endif
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 081a1ef..8114235 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -2215,42 +2215,78 @@ out_free_irq:
return ret;
}
-int kvm_irq_map_gsi(struct kvm *kvm,
- struct kvm_kernel_irq_routing_entry *entries,
- int gsi)
-{
- return 0;
-}
-
-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)
+/**
+ * vgic_irqfd_set_irq: inject the IRQ corresponding to the
+ * irqchip routing entry
+ *
+ * This is the entry point for irqfd IRQ injection
+ */
+static int vgic_irqfd_set_irq(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int irq_source_id,
+ int level, bool line_status)
{
- unsigned int spi = irq + VGIC_NR_PRIVATE_IRQS;
+ unsigned int spi_id = e->irqchip.pin + VGIC_NR_PRIVATE_IRQS;
- trace_kvm_set_irq(irq, level, irq_source_id);
+ trace_kvm_set_irq(spi_id, level, irq_source_id);
BUG_ON(!vgic_initialized(kvm));
- return kvm_vgic_inject_irq(kvm, 0, spi, level);
+ if (spi_id > min(kvm->arch.vgic.nr_irqs, 1020))
+ return -EINVAL;
+ return kvm_vgic_inject_irq(kvm, 0, spi_id, level);
+}
+
+/**
+ * kvm_set_routing_entry: populate a kvm routing entry
+ * from a user routing entry
+ *
+ * @e: kvm kernel routing entry handle
+ * @ue: user api routing entry handle
+ * return 0 on success, -EINVAL on errors.
+ */
+int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e,
+ const struct kvm_irq_routing_entry *ue)
+{
+ int r = -EINVAL;
+
+ switch (ue->type) {
+ case KVM_IRQ_ROUTING_IRQCHIP:
+ e->set = vgic_irqfd_set_irq;
+ e->irqchip.irqchip = ue->u.irqchip.irqchip;
+ e->irqchip.pin = ue->u.irqchip.pin;
+ if ((e->irqchip.pin >= KVM_IRQCHIP_NUM_PINS) ||
+ (e->irqchip.irqchip >= KVM_NR_IRQCHIPS))
+ goto out;
+ break;
+ default:
+ goto out;
+ }
+ r = 0;
+out:
+ return r;
}
-/* MSI not implemented yet */
+/**
+ * kvm_set_msi: inject the MSI corresponding to the
+ * MSI routing entry
+ *
+ * This is the entry point for irqfd MSI injection
+ * and userspace MSI injection.
+ */
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;
-}
+ struct kvm_msi msi;
+
+ msi.address_lo = e->msi.address_lo;
+ msi.address_hi = e->msi.address_hi;
+ msi.data = e->msi.data;
+ msi.flags = e->flags;
+ msi.devid = e->devid;
-int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
-{
if (kvm->arch.vgic.vm_ops.inject_msi)
- return kvm->arch.vgic.vm_ops.inject_msi(kvm, msi);
+ return kvm->arch.vgic.vm_ops.inject_msi(kvm, &msi);
else
return -ENODEV;
}
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
index 75c9931..e1559d4 100644
--- a/virt/kvm/irqchip.c
+++ b/virt/kvm/irqchip.c
@@ -29,7 +29,9 @@
#include <linux/srcu.h>
#include <linux/export.h>
#include <trace/events/kvm.h>
+#if !defined(CONFIG_ARM) && !defined(CONFIG_ARM64)
#include "irq.h"
+#endif
struct kvm_irq_routing_table {
int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
--
1.9.1
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