Re: [PATCH v2 06/10] RISC-V: KVM: Implement device interface for AIA irqchip
From: Yong-Xuan Wang
Date: Thu Jun 15 2023 - 01:33:59 EST
Hi Anup,
On Mon, Jun 12, 2023 at 1:41 PM Anup Patel <apatel@xxxxxxxxxxxxxxxx> wrote:
>
> We implement KVM device interface for in-kernel AIA irqchip so that
> user-space can use KVM device ioctls to create, configure, and destroy
> in-kernel AIA irqchip.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
> arch/riscv/include/asm/kvm_aia.h | 132 +++++--
> arch/riscv/include/uapi/asm/kvm.h | 45 +++
> arch/riscv/kvm/Makefile | 1 +
> arch/riscv/kvm/aia.c | 11 +
> arch/riscv/kvm/aia_device.c | 622 ++++++++++++++++++++++++++++++
> include/uapi/linux/kvm.h | 2 +
> 6 files changed, 771 insertions(+), 42 deletions(-)
> create mode 100644 arch/riscv/kvm/aia_device.c
>
> diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
> index 3bc0a0e47a15..a1281ebc9b92 100644
> --- a/arch/riscv/include/asm/kvm_aia.h
> +++ b/arch/riscv/include/asm/kvm_aia.h
> @@ -20,6 +20,33 @@ struct kvm_aia {
>
> /* In-kernel irqchip initialized */
> bool initialized;
> +
> + /* Virtualization mode (Emulation, HW Accelerated, or Auto) */
> + u32 mode;
> +
> + /* Number of MSIs */
> + u32 nr_ids;
> +
> + /* Number of wired IRQs */
> + u32 nr_sources;
> +
> + /* Number of group bits in IMSIC address */
> + u32 nr_group_bits;
> +
> + /* Position of group bits in IMSIC address */
> + u32 nr_group_shift;
> +
> + /* Number of hart bits in IMSIC address */
> + u32 nr_hart_bits;
> +
> + /* Number of guest bits in IMSIC address */
> + u32 nr_guest_bits;
> +
> + /* Guest physical address of APLIC */
> + gpa_t aplic_addr;
> +
> + /* Internal state of APLIC */
> + void *aplic_state;
> };
>
> struct kvm_vcpu_aia_csr {
> @@ -38,8 +65,19 @@ struct kvm_vcpu_aia {
>
> /* CPU AIA CSR context upon Guest VCPU reset */
> struct kvm_vcpu_aia_csr guest_reset_csr;
> +
> + /* Guest physical address of IMSIC for this VCPU */
> + gpa_t imsic_addr;
> +
> + /* HART index of IMSIC extacted from guest physical address */
> + u32 hart_index;
> +
> + /* Internal state of IMSIC for this VCPU */
> + void *imsic_state;
> };
>
> +#define KVM_RISCV_AIA_UNDEF_ADDR (-1)
> +
> #define kvm_riscv_aia_initialized(k) ((k)->arch.aia.initialized)
>
> #define irqchip_in_kernel(k) ((k)->arch.aia.in_kernel)
> @@ -50,10 +88,17 @@ DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
> #define kvm_riscv_aia_available() \
> static_branch_unlikely(&kvm_riscv_aia_available)
>
> +extern struct kvm_device_ops kvm_riscv_aia_device_ops;
> +
> static inline void kvm_riscv_vcpu_aia_imsic_release(struct kvm_vcpu *vcpu)
> {
> }
>
> +static inline int kvm_riscv_vcpu_aia_imsic_update(struct kvm_vcpu *vcpu)
> +{
> + return 1;
> +}
> +
> #define KVM_RISCV_AIA_IMSIC_TOPEI (ISELECT_MASK + 1)
> static inline int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu,
> unsigned long isel,
> @@ -64,6 +109,41 @@ static inline int kvm_riscv_vcpu_aia_imsic_rmw(struct kvm_vcpu *vcpu,
> return 0;
> }
>
> +static inline void kvm_riscv_vcpu_aia_imsic_reset(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline int kvm_riscv_vcpu_aia_imsic_inject(struct kvm_vcpu *vcpu,
> + u32 guest_index, u32 offset,
> + u32 iid)
> +{
> + return 0;
> +}
> +
> +static inline int kvm_riscv_vcpu_aia_imsic_init(struct kvm_vcpu *vcpu)
> +{
> + return 0;
> +}
> +
> +static inline void kvm_riscv_vcpu_aia_imsic_cleanup(struct kvm_vcpu *vcpu)
> +{
> +}
> +
> +static inline int kvm_riscv_aia_aplic_inject(struct kvm *kvm,
> + u32 source, bool level)
> +{
> + return 0;
> +}
> +
> +static inline int kvm_riscv_aia_aplic_init(struct kvm *kvm)
> +{
> + return 0;
> +}
> +
> +static inline void kvm_riscv_aia_aplic_cleanup(struct kvm *kvm)
> +{
> +}
> +
> #ifdef CONFIG_32BIT
> void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu);
> void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu);
> @@ -99,50 +179,18 @@ int kvm_riscv_vcpu_aia_rmw_ireg(struct kvm_vcpu *vcpu, unsigned int csr_num,
> { .base = CSR_SIREG, .count = 1, .func = kvm_riscv_vcpu_aia_rmw_ireg }, \
> { .base = CSR_STOPEI, .count = 1, .func = kvm_riscv_vcpu_aia_rmw_topei },
>
> -static inline int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
> -{
> - return 1;
> -}
> -
> -static inline void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
> -{
> -}
> -
> -static inline int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
> -{
> - return 0;
> -}
> -
> -static inline void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
> -{
> -}
> -
> -static inline int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm,
> - u32 hart_index,
> - u32 guest_index, u32 iid)
> -{
> - return 0;
> -}
> -
> -static inline int kvm_riscv_aia_inject_msi(struct kvm *kvm,
> - struct kvm_msi *msi)
> -{
> - return 0;
> -}
> +int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu);
> +void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu);
> +int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu);
> +void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu);
>
> -static inline int kvm_riscv_aia_inject_irq(struct kvm *kvm,
> - unsigned int irq, bool level)
> -{
> - return 0;
> -}
> +int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm, u32 hart_index,
> + u32 guest_index, u32 iid);
> +int kvm_riscv_aia_inject_msi(struct kvm *kvm, struct kvm_msi *msi);
> +int kvm_riscv_aia_inject_irq(struct kvm *kvm, unsigned int irq, bool level);
>
> -static inline void kvm_riscv_aia_init_vm(struct kvm *kvm)
> -{
> -}
> -
> -static inline void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
> -{
> -}
> +void kvm_riscv_aia_init_vm(struct kvm *kvm);
> +void kvm_riscv_aia_destroy_vm(struct kvm *kvm);
>
> int kvm_riscv_aia_alloc_hgei(int cpu, struct kvm_vcpu *owner,
> void __iomem **hgei_va, phys_addr_t *hgei_pa);
> diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
> index 332d4a274891..047c8fc5bd71 100644
> --- a/arch/riscv/include/uapi/asm/kvm.h
> +++ b/arch/riscv/include/uapi/asm/kvm.h
> @@ -204,6 +204,51 @@ enum KVM_RISCV_SBI_EXT_ID {
> #define KVM_REG_RISCV_SBI_MULTI_REG_LAST \
> KVM_REG_RISCV_SBI_MULTI_REG(KVM_RISCV_SBI_EXT_MAX - 1)
>
> +/* Device Control API: RISC-V AIA */
> +#define KVM_DEV_RISCV_APLIC_ALIGN 0x1000
> +#define KVM_DEV_RISCV_APLIC_SIZE 0x4000
> +#define KVM_DEV_RISCV_APLIC_MAX_HARTS 0x4000
> +#define KVM_DEV_RISCV_IMSIC_ALIGN 0x1000
> +#define KVM_DEV_RISCV_IMSIC_SIZE 0x1000
> +
> +#define KVM_DEV_RISCV_AIA_GRP_CONFIG 0
> +#define KVM_DEV_RISCV_AIA_CONFIG_MODE 0
> +#define KVM_DEV_RISCV_AIA_CONFIG_IDS 1
> +#define KVM_DEV_RISCV_AIA_CONFIG_SRCS 2
> +#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS 3
> +#define KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT 4
> +#define KVM_DEV_RISCV_AIA_CONFIG_HART_BITS 5
> +#define KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS 6
> +
> +/*
> + * Modes of RISC-V AIA device:
> + * 1) EMUL (aka Emulation): Trap-n-emulate IMSIC
> + * 2) HWACCEL (aka HW Acceleration): Virtualize IMSIC using IMSIC guest files
> + * 3) AUTO (aka Automatic): Virtualize IMSIC using IMSIC guest files whenever
> + * available otherwise fallback to trap-n-emulation
> + */
> +#define KVM_DEV_RISCV_AIA_MODE_EMUL 0
> +#define KVM_DEV_RISCV_AIA_MODE_HWACCEL 1
> +#define KVM_DEV_RISCV_AIA_MODE_AUTO 2
> +
> +#define KVM_DEV_RISCV_AIA_IDS_MIN 63
> +#define KVM_DEV_RISCV_AIA_IDS_MAX 2048
> +#define KVM_DEV_RISCV_AIA_SRCS_MAX 1024
> +#define KVM_DEV_RISCV_AIA_GROUP_BITS_MAX 8
> +#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN 24
> +#define KVM_DEV_RISCV_AIA_GROUP_SHIFT_MAX 56
> +#define KVM_DEV_RISCV_AIA_HART_BITS_MAX 16
> +#define KVM_DEV_RISCV_AIA_GUEST_BITS_MAX 8
> +
> +#define KVM_DEV_RISCV_AIA_GRP_ADDR 1
> +#define KVM_DEV_RISCV_AIA_ADDR_APLIC 0
> +#define KVM_DEV_RISCV_AIA_ADDR_IMSIC(__vcpu) (1 + (__vcpu))
> +#define KVM_DEV_RISCV_AIA_ADDR_MAX \
> + (1 + KVM_DEV_RISCV_APLIC_MAX_HARTS)
> +
> +#define KVM_DEV_RISCV_AIA_GRP_CTRL 2
> +#define KVM_DEV_RISCV_AIA_CTRL_INIT 0
> +
> /* One single KVM irqchip, ie. the AIA */
> #define KVM_NR_IRQCHIPS 1
>
> diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
> index 8031b8912a0d..dd69ebe098bd 100644
> --- a/arch/riscv/kvm/Makefile
> +++ b/arch/riscv/kvm/Makefile
> @@ -27,3 +27,4 @@ kvm-y += vcpu_sbi_hsm.o
> kvm-y += vcpu_timer.o
> kvm-$(CONFIG_RISCV_PMU_SBI) += vcpu_pmu.o vcpu_sbi_pmu.o
> kvm-y += aia.o
> +kvm-y += aia_device.o
> diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
> index 18c442c15ff2..585a3b42c52c 100644
> --- a/arch/riscv/kvm/aia.c
> +++ b/arch/riscv/kvm/aia.c
> @@ -631,6 +631,14 @@ int kvm_riscv_aia_init(void)
> if (rc)
> return rc;
>
> + /* Register device operations */
> + rc = kvm_register_device_ops(&kvm_riscv_aia_device_ops,
> + KVM_DEV_TYPE_RISCV_AIA);
> + if (rc) {
> + aia_hgei_exit();
> + return rc;
> + }
> +
> /* Enable KVM AIA support */
> static_branch_enable(&kvm_riscv_aia_available);
>
> @@ -642,6 +650,9 @@ void kvm_riscv_aia_exit(void)
> if (!kvm_riscv_aia_available())
> return;
>
> + /* Unregister device operations */
> + kvm_unregister_device_ops(KVM_DEV_TYPE_RISCV_AIA);
> +
> /* Cleanup the HGEI state */
> aia_hgei_exit();
> }
> diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
> new file mode 100644
> index 000000000000..a151fb357887
> --- /dev/null
> +++ b/arch/riscv/kvm/aia_device.c
> @@ -0,0 +1,622 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2021 Western Digital Corporation or its affiliates.
> + * Copyright (C) 2022 Ventana Micro Systems Inc.
> + *
> + * Authors:
> + * Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> + */
> +
> +#include <linux/bits.h>
> +#include <linux/kvm_host.h>
> +#include <linux/uaccess.h>
> +#include <asm/kvm_aia_imsic.h>
> +
> +static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
> +{
> + struct kvm_vcpu *tmp_vcpu;
> +
> + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
> + tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
> + mutex_unlock(&tmp_vcpu->mutex);
> + }
> +}
> +
> +static void unlock_all_vcpus(struct kvm *kvm)
> +{
> + unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
> +}
> +
> +static bool lock_all_vcpus(struct kvm *kvm)
> +{
> + struct kvm_vcpu *tmp_vcpu;
> + unsigned long c;
> +
> + kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
> + if (!mutex_trylock(&tmp_vcpu->mutex)) {
> + unlock_vcpus(kvm, c - 1);
> + return false;
> + }
> + }
> +
> + return true;
> +}
> +
> +static int aia_create(struct kvm_device *dev, u32 type)
> +{
> + int ret;
> + unsigned long i;
> + struct kvm *kvm = dev->kvm;
> + struct kvm_vcpu *vcpu;
> +
> + if (irqchip_in_kernel(kvm))
> + return -EEXIST;
> +
> + ret = -EBUSY;
> + if (!lock_all_vcpus(kvm))
> + return ret;
> +
> + kvm_for_each_vcpu(i, vcpu, kvm) {
> + if (vcpu->arch.ran_atleast_once)
> + goto out_unlock;
> + }
> + ret = 0;
> +
> + kvm->arch.aia.in_kernel = true;
> +
> +out_unlock:
> + unlock_all_vcpus(kvm);
> + return ret;
> +}
> +
> +static void aia_destroy(struct kvm_device *dev)
> +{
> + kfree(dev);
> +}
> +
> +static int aia_config(struct kvm *kvm, unsigned long type,
> + u32 *nr, bool write)
> +{
> + struct kvm_aia *aia = &kvm->arch.aia;
> +
> + /* Writes can only be done before irqchip is initialized */
> + if (write && kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + switch (type) {
> + case KVM_DEV_RISCV_AIA_CONFIG_MODE:
> + if (write) {
> + switch (*nr) {
> + case KVM_DEV_RISCV_AIA_MODE_EMUL:
> + break;
> + case KVM_DEV_RISCV_AIA_MODE_HWACCEL:
> + case KVM_DEV_RISCV_AIA_MODE_AUTO:
> + /*
> + * HW Acceleration and Auto modes only
> + * supported on host with non-zero guest
> + * external interrupts (i.e. non-zero
> + * VS-level IMSIC pages).
> + */
> + if (!kvm_riscv_aia_nr_hgei)
> + return -EINVAL;
> + break;
> + default:
> + return -EINVAL;
> + };
> + aia->mode = *nr;
> + } else
> + *nr = aia->mode;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_IDS:
> + if (write) {
> + if ((*nr < KVM_DEV_RISCV_AIA_IDS_MIN) ||
> + (*nr >= KVM_DEV_RISCV_AIA_IDS_MAX) ||
> + (*nr & KVM_DEV_RISCV_AIA_IDS_MIN) ||
The msi number is one less than a multiple of 64. This line should be
((*nr & KVM_DEV_RISCV_AIA_IDS_MIN) != KVM_DEV_RISCV_AIA_IDS_MIN)
> + (kvm_riscv_aia_max_ids <= *nr))
> + return -EINVAL;
> + aia->nr_ids = *nr;
> + } else
> + *nr = aia->nr_ids;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_SRCS:
> + if (write) {
> + if ((*nr >= KVM_DEV_RISCV_AIA_SRCS_MAX) ||
> + (*nr >= kvm_riscv_aia_max_ids))
> + return -EINVAL;
> + aia->nr_sources = *nr;
> + } else
> + *nr = aia->nr_sources;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS:
> + if (write) {
> + if (*nr >= KVM_DEV_RISCV_AIA_GROUP_BITS_MAX)
> + return -EINVAL;
> + aia->nr_group_bits = *nr;
> + } else
> + *nr = aia->nr_group_bits;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT:
> + if (write) {
> + if ((*nr < KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN) ||
> + (*nr >= KVM_DEV_RISCV_AIA_GROUP_SHIFT_MAX))
> + return -EINVAL;
> + aia->nr_group_shift = *nr;
> + } else
> + *nr = aia->nr_group_shift;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_HART_BITS:
> + if (write) {
> + if (*nr >= KVM_DEV_RISCV_AIA_HART_BITS_MAX)
> + return -EINVAL;
> + aia->nr_hart_bits = *nr;
> + } else
> + *nr = aia->nr_hart_bits;
> + break;
> + case KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS:
> + if (write) {
> + if (*nr >= KVM_DEV_RISCV_AIA_GUEST_BITS_MAX)
> + return -EINVAL;
> + aia->nr_guest_bits = *nr;
> + } else
> + *nr = aia->nr_guest_bits;
> + break;
> + default:
> + return -ENXIO;
> + };
> +
> + return 0;
> +}
> +
> +static int aia_aplic_addr(struct kvm *kvm, u64 *addr, bool write)
> +{
> + struct kvm_aia *aia = &kvm->arch.aia;
> +
> + if (write) {
> + /* Writes can only be done before irqchip is initialized */
> + if (kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + if (*addr & (KVM_DEV_RISCV_APLIC_ALIGN - 1))
> + return -EINVAL;
> +
> + aia->aplic_addr = *addr;
> + } else
> + *addr = aia->aplic_addr;
> +
> + return 0;
> +}
> +
> +static int aia_imsic_addr(struct kvm *kvm, u64 *addr,
> + unsigned long vcpu_idx, bool write)
> +{
> + struct kvm_vcpu *vcpu;
> + struct kvm_vcpu_aia *vcpu_aia;
> +
> + vcpu = kvm_get_vcpu(kvm, vcpu_idx);
> + if (!vcpu)
> + return -EINVAL;
> + vcpu_aia = &vcpu->arch.aia_context;
> +
> + if (write) {
> + /* Writes can only be done before irqchip is initialized */
> + if (kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + if (*addr & (KVM_DEV_RISCV_IMSIC_ALIGN - 1))
> + return -EINVAL;
> + }
> +
> + mutex_lock(&vcpu->mutex);
> + if (write)
> + vcpu_aia->imsic_addr = *addr;
> + else
> + *addr = vcpu_aia->imsic_addr;
> + mutex_unlock(&vcpu->mutex);
> +
> + return 0;
> +}
> +
> +static gpa_t aia_imsic_ppn(struct kvm_aia *aia, gpa_t addr)
> +{
> + u32 h, l;
> + gpa_t mask = 0;
> +
> + h = aia->nr_hart_bits + aia->nr_guest_bits +
> + IMSIC_MMIO_PAGE_SHIFT - 1;
> + mask = GENMASK_ULL(h, 0);
> +
> + if (aia->nr_group_bits) {
> + h = aia->nr_group_bits + aia->nr_group_shift - 1;
> + l = aia->nr_group_shift;
> + mask |= GENMASK_ULL(h, l);
> + }
> +
> + return (addr & ~mask) >> IMSIC_MMIO_PAGE_SHIFT;
> +}
> +
> +static u32 aia_imsic_hart_index(struct kvm_aia *aia, gpa_t addr)
> +{
> + u32 hart, group = 0;
> +
> + hart = (addr >> (aia->nr_guest_bits + IMSIC_MMIO_PAGE_SHIFT)) &
> + GENMASK_ULL(aia->nr_hart_bits - 1, 0);
> + if (aia->nr_group_bits)
> + group = (addr >> aia->nr_group_shift) &
> + GENMASK_ULL(aia->nr_group_bits - 1, 0);
> +
> + return (group << aia->nr_hart_bits) | hart;
> +}
> +
> +static int aia_init(struct kvm *kvm)
> +{
> + int ret, i;
> + unsigned long idx;
> + struct kvm_vcpu *vcpu;
> + struct kvm_vcpu_aia *vaia;
> + struct kvm_aia *aia = &kvm->arch.aia;
> + gpa_t base_ppn = KVM_RISCV_AIA_UNDEF_ADDR;
> +
> + /* Irqchip can be initialized only once */
> + if (kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + /* We might be in the middle of creating a VCPU? */
> + if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus))
> + return -EBUSY;
> +
> + /* Number of sources should be less than or equals number of IDs */
> + if (aia->nr_ids < aia->nr_sources)
> + return -EINVAL;
> +
> + /* APLIC base is required for non-zero number of sources */
> + if (aia->nr_sources && aia->aplic_addr == KVM_RISCV_AIA_UNDEF_ADDR)
> + return -EINVAL;
> +
> + /* Initialize APLIC */
> + ret = kvm_riscv_aia_aplic_init(kvm);
> + if (ret)
> + return ret;
> +
> + /* Iterate over each VCPU */
> + kvm_for_each_vcpu(idx, vcpu, kvm) {
> + vaia = &vcpu->arch.aia_context;
> +
> + /* IMSIC base is required */
> + if (vaia->imsic_addr == KVM_RISCV_AIA_UNDEF_ADDR) {
> + ret = -EINVAL;
> + goto fail_cleanup_imsics;
> + }
> +
> + /* All IMSICs should have matching base PPN */
> + if (base_ppn == KVM_RISCV_AIA_UNDEF_ADDR)
> + base_ppn = aia_imsic_ppn(aia, vaia->imsic_addr);
> + if (base_ppn != aia_imsic_ppn(aia, vaia->imsic_addr)) {
> + ret = -EINVAL;
> + goto fail_cleanup_imsics;
> + }
> +
> + /* Update HART index of the IMSIC based on IMSIC base */
> + vaia->hart_index = aia_imsic_hart_index(aia,
> + vaia->imsic_addr);
> +
> + /* Initialize IMSIC for this VCPU */
> + ret = kvm_riscv_vcpu_aia_imsic_init(vcpu);
> + if (ret)
> + goto fail_cleanup_imsics;
> + }
> +
> + /* Set the initialized flag */
> + kvm->arch.aia.initialized = true;
> +
> + return 0;
> +
> +fail_cleanup_imsics:
> + for (i = idx - 1; i >= 0; i--) {
> + vcpu = kvm_get_vcpu(kvm, i);
> + if (!vcpu)
> + continue;
> + kvm_riscv_vcpu_aia_imsic_cleanup(vcpu);
> + }
> + kvm_riscv_aia_aplic_cleanup(kvm);
> + return ret;
> +}
> +
> +static int aia_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> +{
> + u32 nr;
> + u64 addr;
> + int nr_vcpus, r = -ENXIO;
> + unsigned long type = (unsigned long)attr->attr;
> + void __user *uaddr = (void __user *)(long)attr->addr;
> +
> + switch (attr->group) {
> + case KVM_DEV_RISCV_AIA_GRP_CONFIG:
> + if (copy_from_user(&nr, uaddr, sizeof(nr)))
> + return -EFAULT;
> +
> + mutex_lock(&dev->kvm->lock);
> + r = aia_config(dev->kvm, type, &nr, true);
> + mutex_unlock(&dev->kvm->lock);
> +
> + break;
> +
> + case KVM_DEV_RISCV_AIA_GRP_ADDR:
> + if (copy_from_user(&addr, uaddr, sizeof(addr)))
> + return -EFAULT;
> +
> + nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
> + mutex_lock(&dev->kvm->lock);
> + if (type == KVM_DEV_RISCV_AIA_ADDR_APLIC)
> + r = aia_aplic_addr(dev->kvm, &addr, true);
> + else if (type < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
> + r = aia_imsic_addr(dev->kvm, &addr,
> + type - KVM_DEV_RISCV_AIA_ADDR_IMSIC(0), true);
> + mutex_unlock(&dev->kvm->lock);
> +
> + break;
> +
> + case KVM_DEV_RISCV_AIA_GRP_CTRL:
> + switch (type) {
> + case KVM_DEV_RISCV_AIA_CTRL_INIT:
> + mutex_lock(&dev->kvm->lock);
> + r = aia_init(dev->kvm);
> + mutex_unlock(&dev->kvm->lock);
> + break;
> + }
> +
> + break;
> + }
> +
> + return r;
> +}
> +
> +static int aia_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> +{
> + u32 nr;
> + u64 addr;
> + int nr_vcpus, r = -ENXIO;
> + void __user *uaddr = (void __user *)(long)attr->addr;
> + unsigned long type = (unsigned long)attr->attr;
> +
> + switch (attr->group) {
> + case KVM_DEV_RISCV_AIA_GRP_CONFIG:
> + if (copy_from_user(&nr, uaddr, sizeof(nr)))
> + return -EFAULT;
> +
> + mutex_lock(&dev->kvm->lock);
> + r = aia_config(dev->kvm, type, &nr, false);
> + mutex_unlock(&dev->kvm->lock);
> + if (r)
> + return r;
> +
> + if (copy_to_user(uaddr, &nr, sizeof(nr)))
> + return -EFAULT;
> +
> + break;
> + case KVM_DEV_RISCV_AIA_GRP_ADDR:
> + if (copy_from_user(&addr, uaddr, sizeof(addr)))
> + return -EFAULT;
> +
> + nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
> + mutex_lock(&dev->kvm->lock);
> + if (type == KVM_DEV_RISCV_AIA_ADDR_APLIC)
> + r = aia_aplic_addr(dev->kvm, &addr, false);
> + else if (type < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
> + r = aia_imsic_addr(dev->kvm, &addr,
> + type - KVM_DEV_RISCV_AIA_ADDR_IMSIC(0), false);
> + mutex_unlock(&dev->kvm->lock);
> + if (r)
> + return r;
> +
> + if (copy_to_user(uaddr, &addr, sizeof(addr)))
> + return -EFAULT;
> +
> + break;
> + }
> +
> + return r;
> +}
> +
> +static int aia_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
> +{
> + int nr_vcpus;
> +
> + switch (attr->group) {
> + case KVM_DEV_RISCV_AIA_GRP_CONFIG:
> + switch (attr->attr) {
> + case KVM_DEV_RISCV_AIA_CONFIG_MODE:
> + case KVM_DEV_RISCV_AIA_CONFIG_IDS:
> + case KVM_DEV_RISCV_AIA_CONFIG_SRCS:
> + case KVM_DEV_RISCV_AIA_CONFIG_GROUP_BITS:
> + case KVM_DEV_RISCV_AIA_CONFIG_GROUP_SHIFT:
> + case KVM_DEV_RISCV_AIA_CONFIG_HART_BITS:
> + case KVM_DEV_RISCV_AIA_CONFIG_GUEST_BITS:
> + return 0;
> + }
> + break;
> + case KVM_DEV_RISCV_AIA_GRP_ADDR:
> + nr_vcpus = atomic_read(&dev->kvm->online_vcpus);
> + if (attr->attr == KVM_DEV_RISCV_AIA_ADDR_APLIC)
> + return 0;
> + else if (attr->attr < KVM_DEV_RISCV_AIA_ADDR_IMSIC(nr_vcpus))
> + return 0;
> + break;
> + case KVM_DEV_RISCV_AIA_GRP_CTRL:
> + switch (attr->attr) {
> + case KVM_DEV_RISCV_AIA_CTRL_INIT:
> + return 0;
> + }
> + break;
> + }
> +
> + return -ENXIO;
> +}
> +
> +struct kvm_device_ops kvm_riscv_aia_device_ops = {
> + .name = "kvm-riscv-aia",
> + .create = aia_create,
> + .destroy = aia_destroy,
> + .set_attr = aia_set_attr,
> + .get_attr = aia_get_attr,
> + .has_attr = aia_has_attr,
> +};
> +
> +int kvm_riscv_vcpu_aia_update(struct kvm_vcpu *vcpu)
> +{
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(vcpu->kvm))
> + return 1;
> +
> + /* Update the IMSIC HW state before entering guest mode */
> + return kvm_riscv_vcpu_aia_imsic_update(vcpu);
> +}
> +
> +void kvm_riscv_vcpu_aia_reset(struct kvm_vcpu *vcpu)
> +{
> + struct kvm_vcpu_aia_csr *csr = &vcpu->arch.aia_context.guest_csr;
> + struct kvm_vcpu_aia_csr *reset_csr =
> + &vcpu->arch.aia_context.guest_reset_csr;
> +
> + if (!kvm_riscv_aia_available())
> + return;
> + memcpy(csr, reset_csr, sizeof(*csr));
> +
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(vcpu->kvm))
> + return;
> +
> + /* Reset the IMSIC context */
> + kvm_riscv_vcpu_aia_imsic_reset(vcpu);
> +}
> +
> +int kvm_riscv_vcpu_aia_init(struct kvm_vcpu *vcpu)
> +{
> + struct kvm_vcpu_aia *vaia = &vcpu->arch.aia_context;
> +
> + if (!kvm_riscv_aia_available())
> + return 0;
> +
> + /*
> + * We don't do any memory allocations over here because these
> + * will be done after AIA device is initialized by the user-space.
> + *
> + * Refer, aia_init() implementation for more details.
> + */
> +
> + /* Initialize default values in AIA vcpu context */
> + vaia->imsic_addr = KVM_RISCV_AIA_UNDEF_ADDR;
> + vaia->hart_index = vcpu->vcpu_idx;
> +
> + return 0;
> +}
> +
> +void kvm_riscv_vcpu_aia_deinit(struct kvm_vcpu *vcpu)
> +{
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(vcpu->kvm))
> + return;
> +
> + /* Cleanup IMSIC context */
> + kvm_riscv_vcpu_aia_imsic_cleanup(vcpu);
> +}
> +
> +int kvm_riscv_aia_inject_msi_by_id(struct kvm *kvm, u32 hart_index,
> + u32 guest_index, u32 iid)
> +{
> + unsigned long idx;
> + struct kvm_vcpu *vcpu;
> +
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + /* Inject MSI to matching VCPU */
> + kvm_for_each_vcpu(idx, vcpu, kvm) {
> + if (vcpu->arch.aia_context.hart_index == hart_index)
> + return kvm_riscv_vcpu_aia_imsic_inject(vcpu,
> + guest_index,
> + 0, iid);
> + }
> +
> + return 0;
> +}
> +
> +int kvm_riscv_aia_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
> +{
> + gpa_t tppn, ippn;
> + unsigned long idx;
> + struct kvm_vcpu *vcpu;
> + u32 g, toff, iid = msi->data;
> + struct kvm_aia *aia = &kvm->arch.aia;
> + gpa_t target = (((gpa_t)msi->address_hi) << 32) | msi->address_lo;
> +
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + /* Convert target address to target PPN */
> + tppn = target >> IMSIC_MMIO_PAGE_SHIFT;
> +
> + /* Extract and clear Guest ID from target PPN */
> + g = tppn & (BIT(aia->nr_guest_bits) - 1);
> + tppn &= ~((gpa_t)(BIT(aia->nr_guest_bits) - 1));
> +
> + /* Inject MSI to matching VCPU */
> + kvm_for_each_vcpu(idx, vcpu, kvm) {
> + ippn = vcpu->arch.aia_context.imsic_addr >>
> + IMSIC_MMIO_PAGE_SHIFT;
> + if (ippn == tppn) {
> + toff = target & (IMSIC_MMIO_PAGE_SZ - 1);
> + return kvm_riscv_vcpu_aia_imsic_inject(vcpu, g,
> + toff, iid);
> + }
> + }
> +
> + return 0;
> +}
> +
> +int kvm_riscv_aia_inject_irq(struct kvm *kvm, unsigned int irq, bool level)
> +{
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(kvm))
> + return -EBUSY;
> +
> + /* Inject interrupt level change in APLIC */
> + return kvm_riscv_aia_aplic_inject(kvm, irq, level);
> +}
> +
> +void kvm_riscv_aia_init_vm(struct kvm *kvm)
> +{
> + struct kvm_aia *aia = &kvm->arch.aia;
> +
> + if (!kvm_riscv_aia_available())
> + return;
> +
> + /*
> + * We don't do any memory allocations over here because these
> + * will be done after AIA device is initialized by the user-space.
> + *
> + * Refer, aia_init() implementation for more details.
> + */
> +
> + /* Initialize default values in AIA global context */
> + aia->mode = (kvm_riscv_aia_nr_hgei) ?
> + KVM_DEV_RISCV_AIA_MODE_AUTO : KVM_DEV_RISCV_AIA_MODE_EMUL;
> + aia->nr_ids = kvm_riscv_aia_max_ids - 1;
> + aia->nr_sources = 0;
> + aia->nr_group_bits = 0;
> + aia->nr_group_shift = KVM_DEV_RISCV_AIA_GROUP_SHIFT_MIN;
> + aia->nr_hart_bits = 0;
> + aia->nr_guest_bits = 0;
> + aia->aplic_addr = KVM_RISCV_AIA_UNDEF_ADDR;
> +}
> +
> +void kvm_riscv_aia_destroy_vm(struct kvm *kvm)
> +{
> + /* Proceed only if AIA was initialized successfully */
> + if (!kvm_riscv_aia_initialized(kvm))
> + return;
> +
> + /* Cleanup APLIC context */
> + kvm_riscv_aia_aplic_cleanup(kvm);
> +}
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 737318b1c1d9..27ccd07898e1 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1442,6 +1442,8 @@ enum kvm_device_type {
> #define KVM_DEV_TYPE_XIVE KVM_DEV_TYPE_XIVE
> KVM_DEV_TYPE_ARM_PV_TIME,
> #define KVM_DEV_TYPE_ARM_PV_TIME KVM_DEV_TYPE_ARM_PV_TIME
> + KVM_DEV_TYPE_RISCV_AIA,
> +#define KVM_DEV_TYPE_RISCV_AIA KVM_DEV_TYPE_RISCV_AIA
> KVM_DEV_TYPE_MAX,
> };
>
> --
> 2.34.1
>
Additionally, it might be necessary to consider adding KVM_CAP_IRQCHIP
in the kvm_vm_ioctl_check_extension() function when the KVM AIA chip
is present.
Regards,
Yong-Xuan