[RFC PATCH v3 2/5] arm/arm64: vgic-new: Add distributor and redistributor access
vijay.kilari at gmail.com
vijay.kilari at gmail.com
Wed Aug 24 04:20:06 PDT 2016
From: Vijaya Kumar K <Vijaya.Kumar at cavium.com>
VGICv3 Distributor and Redistributor registers are accessed using
KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_DIST_REGS
with KVM_SET_DEVICE_ATTR and KVM_GET_DEVICE_ATTR ioctls.
These registers are accessed as 32-bit and cpu mpidr
value passed along with register offset is used to identify the
cpu for redistributor registers access.
The version of VGIC v3 specification is define here
http://lists.infradead.org/pipermail/linux-arm-kernel/2016-July/445611.html
Signed-off-by: Vijaya Kumar K <Vijaya.Kumar at cavium.com>
---
arch/arm64/include/uapi/asm/kvm.h | 3 +
virt/kvm/arm/vgic/vgic-kvm-device.c | 127 +++++++++++++++++++++++++++++++++++-
virt/kvm/arm/vgic/vgic-mmio-v3.c | 113 ++++++++++++++++++++++++++++++++
virt/kvm/arm/vgic/vgic-mmio.c | 2 +-
virt/kvm/arm/vgic/vgic.h | 8 +++
5 files changed, 250 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 3051f86..94ea676 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -201,10 +201,13 @@ struct kvm_arch_memory_slot {
#define KVM_DEV_ARM_VGIC_GRP_CPU_REGS 2
#define KVM_DEV_ARM_VGIC_CPUID_SHIFT 32
#define KVM_DEV_ARM_VGIC_CPUID_MASK (0xffULL << KVM_DEV_ARM_VGIC_CPUID_SHIFT)
+#define KVM_DEV_ARM_VGIC_V3_CPUID_MASK \
+ (0xffffffffULL << KVM_DEV_ARM_VGIC_CPUID_SHIFT)
#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0
#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT)
#define KVM_DEV_ARM_VGIC_GRP_NR_IRQS 3
#define KVM_DEV_ARM_VGIC_GRP_CTRL 4
+#define KVM_DEV_ARM_VGIC_GRP_REDIST_REGS 5
#define KVM_DEV_ARM_VGIC_CTRL_INIT 0
/* Device Control API on vcpu fd */
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 163b057..06f0158 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -433,16 +433,136 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = {
#ifdef CONFIG_KVM_ARM_VGIC_V3
+static int parse_vgic_v3_attr(struct kvm_device *dev,
+ struct kvm_device_attr *attr,
+ struct vgic_reg_attr *reg_attr)
+{
+ int cpuid;
+
+ cpuid = (attr->attr & KVM_DEV_ARM_VGIC_V3_CPUID_MASK) >>
+ KVM_DEV_ARM_VGIC_CPUID_SHIFT;
+
+ if (cpuid >= atomic_read(&dev->kvm->online_vcpus))
+ return -EINVAL;
+
+ reg_attr->vcpu = kvm_mpidr_to_vcpu(dev->kvm, cpuid);
+ reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+
+ return 0;
+}
+
+/**
+ * vgic_attr_regs_access_v3 - allows user space to access VGIC v3 state
+ *
+ * @dev: kvm device handle
+ * @attr: kvm device attribute
+ * @reg: address the value is read or written
+ * @is_write: true if userspace is writing a register
+ */
+static int vgic_attr_regs_access_v3(struct kvm_device *dev,
+ struct kvm_device_attr *attr,
+ u64 *reg, bool is_write)
+{
+ struct vgic_reg_attr reg_attr;
+ gpa_t addr;
+ struct kvm_vcpu *vcpu;
+ int ret;
+ u32 tmp32;
+
+ ret = parse_vgic_v3_attr(dev, attr, ®_attr);
+ if (ret)
+ return ret;
+
+ vcpu = reg_attr.vcpu;
+ addr = reg_attr.addr;
+
+ mutex_lock(&dev->kvm->lock);
+
+ ret = vgic_init(dev->kvm);
+ if (ret)
+ goto out;
+
+ if (!lock_all_vcpus(dev->kvm)) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ tmp32 = *reg;
+ ret = vgic_v3_dist_uaccess(vcpu, is_write, addr, &tmp32);
+ if (!is_write)
+ *reg = tmp32;
+ break;
+ case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS:
+ tmp32 = *reg;
+ ret = vgic_v3_redist_uaccess(vcpu, is_write, addr, &tmp32);
+ if (!is_write)
+ *reg = tmp32;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ unlock_all_vcpus(dev->kvm);
+out:
+ mutex_unlock(&dev->kvm->lock);
+ return ret;
+}
+
static int vgic_v3_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return vgic_set_common_attr(dev, attr);
+ int ret;
+
+ ret = vgic_set_common_attr(dev, attr);
+ if (ret != -ENXIO)
+ return ret;
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u32 tmp32;
+ u64 reg;
+
+ if (get_user(tmp32, uaddr))
+ return -EFAULT;
+
+ reg = tmp32;
+ return vgic_attr_regs_access_v3(dev, attr, ®, true);
+ }
+ }
+ return -ENXIO;
}
static int vgic_v3_get_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return vgic_get_common_attr(dev, attr);
+ int ret;
+
+ ret = vgic_get_common_attr(dev, attr);
+ if (ret != -ENXIO)
+ return ret;
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u64 reg;
+ u32 tmp32;
+
+ ret = vgic_attr_regs_access_v3(dev, attr, ®, false);
+ if (ret)
+ return ret;
+ tmp32 = reg;
+ ret = put_user(tmp32, uaddr);
+ return ret;
+ }
+ }
+
+ return -ENXIO;
}
static int vgic_v3_has_attr(struct kvm_device *dev,
@@ -456,6 +576,9 @@ static int vgic_v3_has_attr(struct kvm_device *dev,
return 0;
}
break;
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS:
+ return vgic_v3_has_attr_regs(dev, attr);
case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
return 0;
case KVM_DEV_ARM_VGIC_GRP_CTRL:
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index dd0d602..c2df103 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -18,6 +18,8 @@
#include <kvm/arm_vgic.h>
#include <asm/kvm_emulate.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
#include "vgic.h"
#include "vgic-mmio.h"
@@ -391,6 +393,9 @@ static const struct vgic_register_region vgic_v3_dist_registers[] = {
REGISTER_DESC_WITH_LENGTH(GICD_CTLR,
vgic_mmio_read_v3_misc, vgic_mmio_write_v3_misc, 16,
VGIC_ACCESS_32bit),
+ REGISTER_DESC_WITH_LENGTH(GICD_STATUSR,
+ vgic_mmio_read_rao, vgic_mmio_write_wi, 4,
+ VGIC_ACCESS_32bit),
REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IGROUPR,
vgic_mmio_read_rao, vgic_mmio_write_wi, 1,
VGIC_ACCESS_32bit),
@@ -438,12 +443,18 @@ static const struct vgic_register_region vgic_v3_rdbase_registers[] = {
REGISTER_DESC_WITH_LENGTH(GICR_CTLR,
vgic_mmio_read_v3r_ctlr, vgic_mmio_write_v3r_ctlr, 4,
VGIC_ACCESS_32bit),
+ REGISTER_DESC_WITH_LENGTH(GICR_STATUSR,
+ vgic_mmio_read_raz, vgic_mmio_write_wi, 4,
+ VGIC_ACCESS_32bit),
REGISTER_DESC_WITH_LENGTH(GICR_IIDR,
vgic_mmio_read_v3r_iidr, vgic_mmio_write_wi, 4,
VGIC_ACCESS_32bit),
REGISTER_DESC_WITH_LENGTH(GICR_TYPER,
vgic_mmio_read_v3r_typer, vgic_mmio_write_wi, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
+ REGISTER_DESC_WITH_LENGTH(GICR_WAKER,
+ vgic_mmio_read_raz, vgic_mmio_write_wi, 8,
+ VGIC_ACCESS_32bit),
REGISTER_DESC_WITH_LENGTH(GICR_PROPBASER,
vgic_mmio_read_propbase, vgic_mmio_write_propbase, 8,
VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
@@ -564,6 +575,46 @@ int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t redist_base_address)
return ret;
}
+int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
+{
+ struct kvm_vcpu *vcpu;
+ int nr_irqs = dev->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
+ const struct vgic_register_region *regions;
+ gpa_t addr;
+ int nr_regions, i, len, cpuid;
+
+ addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+ cpuid = (attr->attr & KVM_DEV_ARM_VGIC_V3_CPUID_MASK) >>
+ KVM_DEV_ARM_VGIC_CPUID_SHIFT;
+ vcpu = kvm_mpidr_to_vcpu(dev->kvm, cpuid);
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ regions = vgic_v3_dist_registers;
+ nr_regions = ARRAY_SIZE(vgic_v3_dist_registers);
+ break;
+ case KVM_DEV_ARM_VGIC_GRP_REDIST_REGS:{
+ regions = vgic_v3_rdbase_registers;
+ nr_regions = ARRAY_SIZE(vgic_v3_rdbase_registers);
+ break;
+ }
+ default:
+ return -ENXIO;
+ }
+
+ for (i = 0; i < nr_regions; i++) {
+ if (regions[i].bits_per_irq)
+ len = (regions[i].bits_per_irq * nr_irqs) / 8;
+ else
+ len = regions[i].len;
+
+ if (regions[i].reg_offset <= addr &&
+ regions[i].reg_offset + len > addr)
+ return 0;
+ }
+
+ return -ENXIO;
+}
/*
* Compare a given affinity (level 1-3 and a level 0 mask, from the SGI
* generation register ICC_SGI1R_EL1) with a given VCPU.
@@ -670,3 +721,65 @@ void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg)
vgic_put_irq(vcpu->kvm, irq);
}
}
+
+/*
+ * When userland tries to access the VGIC register handlers, we need to
+ * create a usable struct vgic_io_device to be passed to the handlers and we
+ * have to set up a buffer similar to what would have happened if a guest MMIO
+ * access occurred, including doing endian conversions on BE systems.
+ */
+static int vgic_v3_uaccess(struct kvm_vcpu *vcpu, struct vgic_io_device *dev,
+ bool is_write, int offset, u32 *val)
+{
+ unsigned int len = 4;
+ u8 buf[4];
+ int ret;
+
+ if (is_write) {
+ vgic_data_host_to_mmio_bus(buf, len, *val);
+ ret = vgic_mmio_uaccess_write(vcpu, &dev->dev, offset,
+ len, buf);
+ } else {
+ ret = vgic_mmio_uaccess_read(vcpu, &dev->dev, offset, len, buf);
+ if (!ret)
+ *val = vgic_data_mmio_bus_to_host(buf, len);
+ }
+
+ return ret;
+}
+
+int vgic_v3_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+ int offset, u32 *val)
+{
+ struct vgic_io_device dev = {
+ .regions = vgic_v3_dist_registers,
+ .nr_regions = ARRAY_SIZE(vgic_v3_dist_registers),
+ };
+
+ return vgic_v3_uaccess(vcpu, &dev, is_write, offset, val);
+}
+
+int vgic_v3_redist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+ int offset, u32 *val)
+{
+ struct vgic_io_device *dev;
+ const struct vgic_register_region *region;
+
+ struct vgic_io_device rd_dev = {
+ .regions = vgic_v3_rdbase_registers,
+ .nr_regions = ARRAY_SIZE(vgic_v3_rdbase_registers),
+ };
+
+ struct vgic_io_device sgi_dev = {
+ .regions = vgic_v3_sgibase_registers,
+ .nr_regions = ARRAY_SIZE(vgic_v3_sgibase_registers),
+ };
+
+ dev = &sgi_dev;
+ region = vgic_find_mmio_region(dev->regions, dev->nr_regions,
+ offset - dev->base_addr);
+ if (region == NULL)
+ dev = &rd_dev;
+
+ return vgic_v3_uaccess(vcpu, dev, is_write, offset, val);
+}
diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c
index dcf5d25..38f2c75 100644
--- a/virt/kvm/arm/vgic/vgic-mmio.c
+++ b/virt/kvm/arm/vgic/vgic-mmio.c
@@ -406,7 +406,7 @@ static int match_region(const void *key, const void *elt)
}
/* Find the proper register handler entry given a certain address offset. */
-static const struct vgic_register_region *
+const struct vgic_register_region *
vgic_find_mmio_region(const struct vgic_register_region *region, int nr_regions,
unsigned int offset)
{
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 1d8e21d..14e4ce5 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -72,6 +72,9 @@ static inline void vgic_get_irq_kref(struct vgic_irq *irq)
kref_get(&irq->refcount);
}
+const struct vgic_register_region *
+ vgic_find_mmio_region(const struct vgic_register_region *region,
+ int nr_regions, unsigned int offset);
#ifdef CONFIG_KVM_ARM_VGIC_V3
void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu);
void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu);
@@ -88,6 +91,11 @@ bool vgic_has_its(struct kvm *kvm);
int kvm_vgic_register_its_device(void);
void vgic_enable_lpis(struct kvm_vcpu *vcpu);
int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi);
+int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr);
+int vgic_v3_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+ int offset, u32 *val);
+int vgic_v3_redist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
+ int offset, u32 *val);
#else
static inline void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
{
--
1.9.1
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