[PATCH v3 06/10] RISC-V: KVM: Implement device interface for AIA irqchip

From: Anup Patel
Date: Thu Jun 15 2023 - 03:35:27 EST


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>
Reviewed-by: Atish Patra <atishp@xxxxxxxxxxxx>
---
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 | 623 ++++++++++++++++++++++++++++++
include/uapi/linux/kvm.h | 2 +
6 files changed, 772 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..7ab555121872
--- /dev/null
+++ b/arch/riscv/kvm/aia_device.c
@@ -0,0 +1,623 @@
+// 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) !=
+ 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