[v14,01/30] LoongArch: KVM: Add kvm related header files

Message ID 20230619083255.3841777-2-zhaotianrui@loongson.cn
State New
Headers
Series Add KVM LoongArch support |

Commit Message

zhaotianrui June 19, 2023, 8:32 a.m. UTC
  Add LoongArch KVM related header files, including kvm.h,
kvm_host.h, kvm_types.h. All of those are about LoongArch
virtualization features and kvm interfaces.

Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 arch/loongarch/include/asm/kvm_host.h  | 253 +++++++++++++++++++++++++
 arch/loongarch/include/asm/kvm_types.h |  11 ++
 arch/loongarch/include/uapi/asm/kvm.h  | 106 +++++++++++
 include/uapi/linux/kvm.h               |   9 +
 4 files changed, 379 insertions(+)
 create mode 100644 arch/loongarch/include/asm/kvm_host.h
 create mode 100644 arch/loongarch/include/asm/kvm_types.h
 create mode 100644 arch/loongarch/include/uapi/asm/kvm.h
  

Comments

Huacai Chen June 19, 2023, 9:59 a.m. UTC | #1
Hi, Tianrui,

On Mon, Jun 19, 2023 at 4:33 PM Tianrui Zhao <zhaotianrui@loongson.cn> wrote:
>
> Add LoongArch KVM related header files, including kvm.h,
> kvm_host.h, kvm_types.h. All of those are about LoongArch
> virtualization features and kvm interfaces.
>
> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
> ---
>  arch/loongarch/include/asm/kvm_host.h  | 253 +++++++++++++++++++++++++
>  arch/loongarch/include/asm/kvm_types.h |  11 ++
>  arch/loongarch/include/uapi/asm/kvm.h  | 106 +++++++++++
>  include/uapi/linux/kvm.h               |   9 +
>  4 files changed, 379 insertions(+)
>  create mode 100644 arch/loongarch/include/asm/kvm_host.h
>  create mode 100644 arch/loongarch/include/asm/kvm_types.h
>  create mode 100644 arch/loongarch/include/uapi/asm/kvm.h
>
> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
> new file mode 100644
> index 000000000000..a8ff3ef9cd55
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_host.h
> @@ -0,0 +1,253 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#ifndef __ASM_LOONGARCH_KVM_HOST_H__
> +#define __ASM_LOONGARCH_KVM_HOST_H__
> +
> +#include <linux/cpumask.h>
> +#include <linux/mutex.h>
> +#include <linux/hrtimer.h>
> +#include <linux/interrupt.h>
> +#include <linux/types.h>
> +#include <linux/kvm.h>
> +#include <linux/kvm_types.h>
> +#include <linux/threads.h>
> +#include <linux/spinlock.h>
> +
> +#include <asm/inst.h>
> +#include <asm/loongarch.h>
> +
> +/* Loongarch KVM register ids */
> +#define LOONGARCH_CSR_32(_R, _S)       \
> +       (KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U32 | (8 * (_R) + (_S)))
> +
> +#define LOONGARCH_CSR_64(_R, _S)       \
> +       (KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | (8 * (_R) + (_S)))
> +
> +#define KVM_IOC_CSRID(id)              LOONGARCH_CSR_64(id, 0)
> +#define KVM_GET_IOC_CSRIDX(id)         ((id & KVM_CSR_IDX_MASK) >> 3)
> +
> +#define KVM_MAX_VCPUS                  256
> +/* memory slots that does not exposed to userspace */
> +#define KVM_PRIVATE_MEM_SLOTS          0
> +
> +#define KVM_HALT_POLL_NS_DEFAULT       500000
> +
> +struct kvm_vm_stat {
> +       struct kvm_vm_stat_generic generic;
> +};
> +
> +struct kvm_vcpu_stat {
> +       struct kvm_vcpu_stat_generic generic;
> +       u64 idle_exits;
> +       u64 signal_exits;
> +       u64 int_exits;
> +       u64 cpucfg_exits;
> +};
> +
> +struct kvm_arch_memory_slot {
> +};
> +
> +struct kvm_context {
> +       unsigned long vpid_cache;
> +       struct kvm_vcpu *last_vcpu;
> +};
> +
> +struct kvm_world_switch {
> +       int (*guest_eentry)(void);
> +       int (*enter_guest)(struct kvm_run *run, struct kvm_vcpu *vcpu);
> +       unsigned long page_order;
> +};
> +
> +struct kvm_arch {
> +       /* Guest physical mm */
> +       struct mm_struct gpa_mm;
> +       /* Mask of CPUs needing GPA ASID flush */
> +       cpumask_t asid_flush_mask;
> +
> +       unsigned char online_vcpus;
> +       unsigned char is_migrate;
is_migrating is better.

> +       s64 time_offset;
> +       struct kvm_context __percpu *vmcs;
> +       unsigned long gpa_size;
Move gpa_size under gpa_mm seems better.
> +};
> +
> +#define CSR_MAX_NUMS           0x800
> +
> +struct loongarch_csrs {
> +       unsigned long csrs[CSR_MAX_NUMS];
> +};
> +
> +/* Resume Flags */
> +#define RESUME_GUEST           1
> +#define RESUME_HOST            0
Exchange their order seems better.

> +
> +enum emulation_result {
> +       EMULATE_DONE,           /* no further processing */
> +       EMULATE_DO_MMIO,        /* kvm_run filled with MMIO request */
> +       EMULATE_FAIL,           /* can't emulate this instruction */
> +       EMULATE_WAIT,           /* WAIT instruction */
EMULATE_IDLE? also the comments should be modified.

> +       EMULATE_EXCEPT,         /* A guest exception has been generated */
> +       EMULATE_DO_IOCSR,       /* handle IOCSR request */
> +};
> +
> +#define KVM_LARCH_FPU          (0x1 << 0)
> +#define KVM_LARCH_CSR          (0x1 << 1)
I want to change their order, just because we will add LSX/LASX, it is
better to let LSX/LASX be together with FPU.

> +
> +struct kvm_vcpu_arch {
> +       /*
> +        * Switch pointer-to-function type to unsigned long
> +        * for loading the value into register directly.
> +        */
> +       unsigned long guest_eentry;
> +       unsigned long host_eentry;
Exchange their order seems better, as above.

> +
> +       /* Pointers stored here for easy accessing from assembly code */
> +       int (*handle_exit)(struct kvm_run *run, struct kvm_vcpu *vcpu);
> +
> +       /* Host registers preserved across guest mode execution */
> +       unsigned long host_sp;
> +       unsigned long host_tp;
> +       unsigned long host_pgd;
> +
> +       /* Host CSRs are used when handling exits from guest */
> +       unsigned long badi;
> +       unsigned long badv;
> +       unsigned long host_ecfg;
> +       unsigned long host_estat;
> +       unsigned long host_percpu;
> +
> +       /* GPRs */
> +       unsigned long gprs[32];
> +       unsigned long pc;
> +
> +       /* FPU state */
> +       struct loongarch_fpu fpu FPU_ALIGN;
> +       /* Which auxiliary state is loaded (KVM_LOONGARCH_AUX_*) */
> +       unsigned int aux_inuse;
I also want to change the order of aux_inuse and fpu, just because we
may add lbt after fpu in future.

> +
> +       /* CSR state */
> +       struct loongarch_csrs *csr;
> +
> +       /* GPR used as IO source/target */
> +       u32 io_gpr;
> +
> +       struct hrtimer swtimer;
> +       /* KVM register to control count timer */
> +       u32 count_ctl;
> +
> +       /* Bitmask of exceptions that are pending */
> +       unsigned long irq_pending;
> +       /* Bitmask of pending exceptions to be cleared */
> +       unsigned long irq_clear;
> +
> +       /* Cache for pages needed inside spinlock regions */
> +       struct kvm_mmu_memory_cache mmu_page_cache;
> +
> +       /* vcpu's vpid */
> +       u64 vpid;
> +
> +       /* Period of stable timer tick in ns */
> +       u64 timer_period_ns;
> +       /* Frequency of stable timer in Hz */
> +       u64 timer_mhz;
> +       /* Stable bias from the raw time */
> +       u64 timer_bias;
> +       /* Dynamic nanosecond bias (multiple of timer_period_ns) to avoid overflow */
> +       s64 timer_dyn_bias;
> +
> +       ktime_t stable_ktime_saved;
> +
> +       u64 core_ext_ioisr[4];
> +
> +       /* Last CPU the vCPU state was loaded on */
> +       int last_sched_cpu;
> +       /* Last CPU the vCPU actually executed guest code on */
> +       int last_exec_cpu;
> +       /* mp state */
> +       struct kvm_mp_state mp_state;
> +};
> +
> +static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg)
> +{
> +       return csr->csrs[reg];
> +}
> +
> +static inline void writel_sw_gcsr(struct loongarch_csrs *csr, int reg,
> +               unsigned long val)
Don't split here, long lines is acceptable now.

> +{
> +       csr->csrs[reg] = val;
> +}
> +
> +/* Helpers */
> +static inline bool _kvm_guest_has_fpu(struct kvm_vcpu_arch *arch)
> +{
> +       return cpu_has_fpu;
> +}
> +
> +void _kvm_init_fault(void);
> +
> +/* Debug: dump vcpu state */
> +int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu);
> +
> +/* MMU handling */
> +int kvm_handle_mm_fault(struct kvm_vcpu *vcpu, unsigned long badv, bool write);
> +void kvm_flush_tlb_all(void);
> +void _kvm_destroy_mm(struct kvm *kvm);
> +pgd_t *kvm_pgd_alloc(void);
> +
> +#define KVM_ARCH_WANT_MMU_NOTIFIER
> +int kvm_unmap_hva_range(struct kvm *kvm,
> +                       unsigned long start, unsigned long end, bool blockable);
> +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
> +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
> +int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
> +
> +static inline void update_pc(struct kvm_vcpu_arch *arch)
> +{
> +       arch->pc += 4;
> +}
> +
> +/**
> + * kvm_is_ifetch_fault() - Find whether a TLBL exception is due to ifetch fault.
> + * @vcpu:      Virtual CPU.
> + *
> + * Returns:    Whether the TLBL exception was likely due to an instruction
> + *             fetch fault rather than a data load fault.
> + */
> +static inline bool kvm_is_ifetch_fault(struct kvm_vcpu_arch *arch)
> +{
> +       return arch->pc == arch->badv;
> +}
> +
> +/* Misc */
> +static inline void kvm_arch_hardware_unsetup(void) {}
> +static inline void kvm_arch_sync_events(struct kvm *kvm) {}
> +static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
> +static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
> +static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
> +static inline void kvm_arch_free_memslot(struct kvm *kvm,
> +                                  struct kvm_memory_slot *slot) {}
> +void _kvm_check_vmid(struct kvm_vcpu *vcpu);
> +enum hrtimer_restart kvm_swtimer_wakeup(struct hrtimer *timer);
> +int kvm_flush_tlb_gpa(struct kvm_vcpu *vcpu, unsigned long gpa);
> +void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
> +                                       const struct kvm_memory_slot *memslot);
> +void kvm_init_vmcs(struct kvm *kvm);
> +void kvm_vector_entry(void);
> +int  kvm_enter_guest(struct kvm_run *run, struct kvm_vcpu *vcpu);
> +extern const unsigned long kvm_vector_size;
> +extern const unsigned long kvm_enter_guest_size;
> +extern unsigned long vpid_mask;
> +extern struct kvm_world_switch *kvm_loongarch_ops;
> +
> +#define SW_GCSR                (1 << 0)
> +#define HW_GCSR                (1 << 1)
> +#define INVALID_GCSR   (1 << 2)
> +int get_gcsr_flag(int csr);
> +extern void set_hw_gcsr(int csr_id, unsigned long val);
> +#endif /* __ASM_LOONGARCH_KVM_HOST_H__ */
> diff --git a/arch/loongarch/include/asm/kvm_types.h b/arch/loongarch/include/asm/kvm_types.h
> new file mode 100644
> index 000000000000..060647b5fe2e
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_types.h
> @@ -0,0 +1,11 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#ifndef _ASM_LOONGARCH_KVM_TYPES_H
> +#define _ASM_LOONGARCH_KVM_TYPES_H
> +
> +#define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE      4
> +
> +#endif /* _ASM_LOONGARCH_KVM_TYPES_H */
> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> new file mode 100644
> index 000000000000..3ccadb73ad8d
> --- /dev/null
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -0,0 +1,106 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#ifndef __UAPI_ASM_LOONGARCH_KVM_H
> +#define __UAPI_ASM_LOONGARCH_KVM_H
> +
> +#include <linux/types.h>
> +
> +/*
> + * KVM Loongarch specific structures and definitions.
> + *
> + * Some parts derived from the x86 version of this file.
> + */
> +
> +#define __KVM_HAVE_READONLY_MEM
> +
> +#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
> +
> +/*
> + * for KVM_GET_REGS and KVM_SET_REGS
> + */
> +struct kvm_regs {
> +       /* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
> +       __u64 gpr[32];
> +       __u64 pc;
> +};
> +
> +/*
> + * for KVM_GET_FPU and KVM_SET_FPU
> + */
> +struct kvm_fpu {
> +       __u32 fcsr;
> +       __u64 fcc;    /* 8x8 */
> +       struct kvm_fpureg {
> +               __u64 val64[4];
> +       } fpr[32];
> +};
> +
> +/*
> + * For LoongArch, we use KVM_SET_ONE_REG and KVM_GET_ONE_REG to access various
> + * registers.  The id field is broken down as follows:
> + *
> + *  bits[63..52] - As per linux/kvm.h
> + *  bits[51..32] - Must be zero.
> + *  bits[31..16] - Register set.
> + *
> + * Register set = 0: GP registers from kvm_regs (see definitions below).
> + *
> + * Register set = 1: CSR registers.
> + *
> + * Register set = 2: KVM specific registers (see definitions below).
> + *
> + * Register set = 3: FPU / SIMD registers (see definitions below).
> + *
> + * Other sets registers may be added in the future.  Each set would
> + * have its own identifier in bits[31..16].
> + */
> +
> +#define KVM_REG_LOONGARCH_GP           (KVM_REG_LOONGARCH | 0x00000ULL)
Maybe KVM_REG_LOONGARCH_GPR is better.

Huacai
> +#define KVM_REG_LOONGARCH_CSR          (KVM_REG_LOONGARCH | 0x10000ULL)
> +#define KVM_REG_LOONGARCH_KVM          (KVM_REG_LOONGARCH | 0x20000ULL)
> +#define KVM_REG_LOONGARCH_FPU          (KVM_REG_LOONGARCH | 0x30000ULL)
> +#define KVM_REG_LOONGARCH_MASK         (KVM_REG_LOONGARCH | 0x30000ULL)
> +#define KVM_CSR_IDX_MASK               (0x10000 - 1)
> +
> +/*
> + * KVM_REG_LOONGARCH_KVM - KVM specific control registers.
> + */
> +
> +#define KVM_REG_LOONGARCH_COUNTER      (KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 3)
> +#define KVM_REG_LOONGARCH_VCPU_RESET   (KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 4)
> +
> +struct kvm_debug_exit_arch {
> +};
> +
> +/* for KVM_SET_GUEST_DEBUG */
> +struct kvm_guest_debug_arch {
> +};
> +
> +/* definition of registers in kvm_run */
> +struct kvm_sync_regs {
> +};
> +
> +/* dummy definition */
> +struct kvm_sregs {
> +};
> +
> +struct kvm_iocsr_entry {
> +       __u32 addr;
> +       __u32 pad;
> +       __u64 data;
> +};
> +
> +struct kvm_loongarch_interrupt {
> +       /* in */
> +       __u32 cpu;
> +       __u32 irq;
> +};
> +
> +#define KVM_NR_IRQCHIPS                1
> +#define KVM_IRQCHIP_NUM_PINS   64
> +#define KVM_MAX_CORES          256
> +
> +#endif /* __UAPI_ASM_LOONGARCH_KVM_H */
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 737318b1c1d9..74d9766277e7 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -264,6 +264,7 @@ struct kvm_xen_exit {
>  #define KVM_EXIT_RISCV_SBI        35
>  #define KVM_EXIT_RISCV_CSR        36
>  #define KVM_EXIT_NOTIFY           37
> +#define KVM_EXIT_LOONGARCH_IOCSR  38
>
>  /* For KVM_EXIT_INTERNAL_ERROR */
>  /* Emulate instruction failed. */
> @@ -336,6 +337,13 @@ struct kvm_run {
>                         __u32 len;
>                         __u8  is_write;
>                 } mmio;
> +               /* KVM_EXIT_LOONGARCH_IOCSR */
> +               struct {
> +                       __u64 phys_addr;
> +                       __u8  data[8];
> +                       __u32 len;
> +                       __u8  is_write;
> +               } iocsr_io;
>                 /* KVM_EXIT_HYPERCALL */
>                 struct {
>                         __u64 nr;
> @@ -1360,6 +1368,7 @@ struct kvm_dirty_tlb {
>  #define KVM_REG_ARM64          0x6000000000000000ULL
>  #define KVM_REG_MIPS           0x7000000000000000ULL
>  #define KVM_REG_RISCV          0x8000000000000000ULL
> +#define KVM_REG_LOONGARCH      0x9000000000000000ULL
>
>  #define KVM_REG_SIZE_SHIFT     52
>  #define KVM_REG_SIZE_MASK      0x00f0000000000000ULL
> --
> 2.39.1
>
  
zhaotianrui June 20, 2023, 1:50 a.m. UTC | #2
在 2023/6/19 下午5:59, Huacai Chen 写道:
> Hi, Tianrui,
>
> On Mon, Jun 19, 2023 at 4:33 PM Tianrui Zhao <zhaotianrui@loongson.cn> wrote:
>> Add LoongArch KVM related header files, including kvm.h,
>> kvm_host.h, kvm_types.h. All of those are about LoongArch
>> virtualization features and kvm interfaces.
>>
>> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
>> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
>> ---
>>   arch/loongarch/include/asm/kvm_host.h  | 253 +++++++++++++++++++++++++
>>   arch/loongarch/include/asm/kvm_types.h |  11 ++
>>   arch/loongarch/include/uapi/asm/kvm.h  | 106 +++++++++++
>>   include/uapi/linux/kvm.h               |   9 +
>>   4 files changed, 379 insertions(+)
>>   create mode 100644 arch/loongarch/include/asm/kvm_host.h
>>   create mode 100644 arch/loongarch/include/asm/kvm_types.h
>>   create mode 100644 arch/loongarch/include/uapi/asm/kvm.h
>>
>> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
>> new file mode 100644
>> index 000000000000..a8ff3ef9cd55
>> --- /dev/null
>> +++ b/arch/loongarch/include/asm/kvm_host.h
>> @@ -0,0 +1,253 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
>> + */
>> +
>> +#ifndef __ASM_LOONGARCH_KVM_HOST_H__
>> +#define __ASM_LOONGARCH_KVM_HOST_H__
>> +
>> +#include <linux/cpumask.h>
>> +#include <linux/mutex.h>
>> +#include <linux/hrtimer.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/types.h>
>> +#include <linux/kvm.h>
>> +#include <linux/kvm_types.h>
>> +#include <linux/threads.h>
>> +#include <linux/spinlock.h>
>> +
>> +#include <asm/inst.h>
>> +#include <asm/loongarch.h>
>> +
>> +/* Loongarch KVM register ids */
>> +#define LOONGARCH_CSR_32(_R, _S)       \
>> +       (KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U32 | (8 * (_R) + (_S)))
>> +
>> +#define LOONGARCH_CSR_64(_R, _S)       \
>> +       (KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | (8 * (_R) + (_S)))
>> +
>> +#define KVM_IOC_CSRID(id)              LOONGARCH_CSR_64(id, 0)
>> +#define KVM_GET_IOC_CSRIDX(id)         ((id & KVM_CSR_IDX_MASK) >> 3)
>> +
>> +#define KVM_MAX_VCPUS                  256
>> +/* memory slots that does not exposed to userspace */
>> +#define KVM_PRIVATE_MEM_SLOTS          0
>> +
>> +#define KVM_HALT_POLL_NS_DEFAULT       500000
>> +
>> +struct kvm_vm_stat {
>> +       struct kvm_vm_stat_generic generic;
>> +};
>> +
>> +struct kvm_vcpu_stat {
>> +       struct kvm_vcpu_stat_generic generic;
>> +       u64 idle_exits;
>> +       u64 signal_exits;
>> +       u64 int_exits;
>> +       u64 cpucfg_exits;
>> +};
>> +
>> +struct kvm_arch_memory_slot {
>> +};
>> +
>> +struct kvm_context {
>> +       unsigned long vpid_cache;
>> +       struct kvm_vcpu *last_vcpu;
>> +};
>> +
>> +struct kvm_world_switch {
>> +       int (*guest_eentry)(void);
>> +       int (*enter_guest)(struct kvm_run *run, struct kvm_vcpu *vcpu);
>> +       unsigned long page_order;
>> +};
>> +
>> +struct kvm_arch {
>> +       /* Guest physical mm */
>> +       struct mm_struct gpa_mm;
>> +       /* Mask of CPUs needing GPA ASID flush */
>> +       cpumask_t asid_flush_mask;
>> +
>> +       unsigned char online_vcpus;
>> +       unsigned char is_migrate;
> is_migrating is better.
Thanks, I will rename it to is_migrating.
>
>> +       s64 time_offset;
>> +       struct kvm_context __percpu *vmcs;
>> +       unsigned long gpa_size;
> Move gpa_size under gpa_mm seems better.
Thanks, I will re-order it.
>> +};
>> +
>> +#define CSR_MAX_NUMS           0x800
>> +
>> +struct loongarch_csrs {
>> +       unsigned long csrs[CSR_MAX_NUMS];
>> +};
>> +
>> +/* Resume Flags */
>> +#define RESUME_GUEST           1
>> +#define RESUME_HOST            0
> Exchange their order seems better.
Thanks, I will exchange the two macros.
>
>> +
>> +enum emulation_result {
>> +       EMULATE_DONE,           /* no further processing */
>> +       EMULATE_DO_MMIO,        /* kvm_run filled with MMIO request */
>> +       EMULATE_FAIL,           /* can't emulate this instruction */
>> +       EMULATE_WAIT,           /* WAIT instruction */
> EMULATE_IDLE? also the comments should be modified.
This also could be removed, as it is not used and the idle instruction 
has been emulated in KVM.
>
>> +       EMULATE_EXCEPT,         /* A guest exception has been generated */
>> +       EMULATE_DO_IOCSR,       /* handle IOCSR request */
>> +};
>> +
>> +#define KVM_LARCH_FPU          (0x1 << 0)
>> +#define KVM_LARCH_CSR          (0x1 << 1)
> I want to change their order, just because we will add LSX/LASX, it is
> better to let LSX/LASX be together with FPU.
Thanks, I will re-order them.
>
>> +
>> +struct kvm_vcpu_arch {
>> +       /*
>> +        * Switch pointer-to-function type to unsigned long
>> +        * for loading the value into register directly.
>> +        */
>> +       unsigned long guest_eentry;
>> +       unsigned long host_eentry;
> Exchange their order seems better, as above.
Thanks, I will exchange them.
>
>> +
>> +       /* Pointers stored here for easy accessing from assembly code */
>> +       int (*handle_exit)(struct kvm_run *run, struct kvm_vcpu *vcpu);
>> +
>> +       /* Host registers preserved across guest mode execution */
>> +       unsigned long host_sp;
>> +       unsigned long host_tp;
>> +       unsigned long host_pgd;
>> +
>> +       /* Host CSRs are used when handling exits from guest */
>> +       unsigned long badi;
>> +       unsigned long badv;
>> +       unsigned long host_ecfg;
>> +       unsigned long host_estat;
>> +       unsigned long host_percpu;
>> +
>> +       /* GPRs */
>> +       unsigned long gprs[32];
>> +       unsigned long pc;
>> +
>> +       /* FPU state */
>> +       struct loongarch_fpu fpu FPU_ALIGN;
>> +       /* Which auxiliary state is loaded (KVM_LOONGARCH_AUX_*) */
>> +       unsigned int aux_inuse;
> I also want to change the order of aux_inuse and fpu, just because we
> may add lbt after fpu in future.
I will also re-order them, thanks.
>
>> +
>> +       /* CSR state */
>> +       struct loongarch_csrs *csr;
>> +
>> +       /* GPR used as IO source/target */
>> +       u32 io_gpr;
>> +
>> +       struct hrtimer swtimer;
>> +       /* KVM register to control count timer */
>> +       u32 count_ctl;
>> +
>> +       /* Bitmask of exceptions that are pending */
>> +       unsigned long irq_pending;
>> +       /* Bitmask of pending exceptions to be cleared */
>> +       unsigned long irq_clear;
>> +
>> +       /* Cache for pages needed inside spinlock regions */
>> +       struct kvm_mmu_memory_cache mmu_page_cache;
>> +
>> +       /* vcpu's vpid */
>> +       u64 vpid;
>> +
>> +       /* Period of stable timer tick in ns */
>> +       u64 timer_period_ns;
>> +       /* Frequency of stable timer in Hz */
>> +       u64 timer_mhz;
>> +       /* Stable bias from the raw time */
>> +       u64 timer_bias;
>> +       /* Dynamic nanosecond bias (multiple of timer_period_ns) to avoid overflow */
>> +       s64 timer_dyn_bias;
>> +
>> +       ktime_t stable_ktime_saved;
>> +
>> +       u64 core_ext_ioisr[4];
>> +
>> +       /* Last CPU the vCPU state was loaded on */
>> +       int last_sched_cpu;
>> +       /* Last CPU the vCPU actually executed guest code on */
>> +       int last_exec_cpu;
>> +       /* mp state */
>> +       struct kvm_mp_state mp_state;
>> +};
>> +
>> +static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg)
>> +{
>> +       return csr->csrs[reg];
>> +}
>> +
>> +static inline void writel_sw_gcsr(struct loongarch_csrs *csr, int reg,
>> +               unsigned long val)
> Don't split here, long lines is acceptable now.
Thanks, I will make it in one line.
>
>> +{
>> +       csr->csrs[reg] = val;
>> +}
>> +
>> +/* Helpers */
>> +static inline bool _kvm_guest_has_fpu(struct kvm_vcpu_arch *arch)
>> +{
>> +       return cpu_has_fpu;
>> +}
>> +
>> +void _kvm_init_fault(void);
>> +
>> +/* Debug: dump vcpu state */
>> +int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu);
>> +
>> +/* MMU handling */
>> +int kvm_handle_mm_fault(struct kvm_vcpu *vcpu, unsigned long badv, bool write);
>> +void kvm_flush_tlb_all(void);
>> +void _kvm_destroy_mm(struct kvm *kvm);
>> +pgd_t *kvm_pgd_alloc(void);
>> +
>> +#define KVM_ARCH_WANT_MMU_NOTIFIER
>> +int kvm_unmap_hva_range(struct kvm *kvm,
>> +                       unsigned long start, unsigned long end, bool blockable);
>> +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
>> +int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
>> +int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
>> +
>> +static inline void update_pc(struct kvm_vcpu_arch *arch)
>> +{
>> +       arch->pc += 4;
>> +}
>> +
>> +/**
>> + * kvm_is_ifetch_fault() - Find whether a TLBL exception is due to ifetch fault.
>> + * @vcpu:      Virtual CPU.
>> + *
>> + * Returns:    Whether the TLBL exception was likely due to an instruction
>> + *             fetch fault rather than a data load fault.
>> + */
>> +static inline bool kvm_is_ifetch_fault(struct kvm_vcpu_arch *arch)
>> +{
>> +       return arch->pc == arch->badv;
>> +}
>> +
>> +/* Misc */
>> +static inline void kvm_arch_hardware_unsetup(void) {}
>> +static inline void kvm_arch_sync_events(struct kvm *kvm) {}
>> +static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
>> +static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
>> +static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
>> +static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
>> +static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
>> +static inline void kvm_arch_free_memslot(struct kvm *kvm,
>> +                                  struct kvm_memory_slot *slot) {}
>> +void _kvm_check_vmid(struct kvm_vcpu *vcpu);
>> +enum hrtimer_restart kvm_swtimer_wakeup(struct hrtimer *timer);
>> +int kvm_flush_tlb_gpa(struct kvm_vcpu *vcpu, unsigned long gpa);
>> +void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
>> +                                       const struct kvm_memory_slot *memslot);
>> +void kvm_init_vmcs(struct kvm *kvm);
>> +void kvm_vector_entry(void);
>> +int  kvm_enter_guest(struct kvm_run *run, struct kvm_vcpu *vcpu);
>> +extern const unsigned long kvm_vector_size;
>> +extern const unsigned long kvm_enter_guest_size;
>> +extern unsigned long vpid_mask;
>> +extern struct kvm_world_switch *kvm_loongarch_ops;
>> +
>> +#define SW_GCSR                (1 << 0)
>> +#define HW_GCSR                (1 << 1)
>> +#define INVALID_GCSR   (1 << 2)
>> +int get_gcsr_flag(int csr);
>> +extern void set_hw_gcsr(int csr_id, unsigned long val);
>> +#endif /* __ASM_LOONGARCH_KVM_HOST_H__ */
>> diff --git a/arch/loongarch/include/asm/kvm_types.h b/arch/loongarch/include/asm/kvm_types.h
>> new file mode 100644
>> index 000000000000..060647b5fe2e
>> --- /dev/null
>> +++ b/arch/loongarch/include/asm/kvm_types.h
>> @@ -0,0 +1,11 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
>> + */
>> +
>> +#ifndef _ASM_LOONGARCH_KVM_TYPES_H
>> +#define _ASM_LOONGARCH_KVM_TYPES_H
>> +
>> +#define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE      4
>> +
>> +#endif /* _ASM_LOONGARCH_KVM_TYPES_H */
>> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
>> new file mode 100644
>> index 000000000000..3ccadb73ad8d
>> --- /dev/null
>> +++ b/arch/loongarch/include/uapi/asm/kvm.h
>> @@ -0,0 +1,106 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
>> + */
>> +
>> +#ifndef __UAPI_ASM_LOONGARCH_KVM_H
>> +#define __UAPI_ASM_LOONGARCH_KVM_H
>> +
>> +#include <linux/types.h>
>> +
>> +/*
>> + * KVM Loongarch specific structures and definitions.
>> + *
>> + * Some parts derived from the x86 version of this file.
>> + */
>> +
>> +#define __KVM_HAVE_READONLY_MEM
>> +
>> +#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
>> +
>> +/*
>> + * for KVM_GET_REGS and KVM_SET_REGS
>> + */
>> +struct kvm_regs {
>> +       /* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
>> +       __u64 gpr[32];
>> +       __u64 pc;
>> +};
>> +
>> +/*
>> + * for KVM_GET_FPU and KVM_SET_FPU
>> + */
>> +struct kvm_fpu {
>> +       __u32 fcsr;
>> +       __u64 fcc;    /* 8x8 */
>> +       struct kvm_fpureg {
>> +               __u64 val64[4];
>> +       } fpr[32];
>> +};
>> +
>> +/*
>> + * For LoongArch, we use KVM_SET_ONE_REG and KVM_GET_ONE_REG to access various
>> + * registers.  The id field is broken down as follows:
>> + *
>> + *  bits[63..52] - As per linux/kvm.h
>> + *  bits[51..32] - Must be zero.
>> + *  bits[31..16] - Register set.
>> + *
>> + * Register set = 0: GP registers from kvm_regs (see definitions below).
>> + *
>> + * Register set = 1: CSR registers.
>> + *
>> + * Register set = 2: KVM specific registers (see definitions below).
>> + *
>> + * Register set = 3: FPU / SIMD registers (see definitions below).
>> + *
>> + * Other sets registers may be added in the future.  Each set would
>> + * have its own identifier in bits[31..16].
>> + */
>> +
>> +#define KVM_REG_LOONGARCH_GP           (KVM_REG_LOONGARCH | 0x00000ULL)
> Maybe KVM_REG_LOONGARCH_GPR is better.
>
> Huacai
I will change it to KVM_REG_LOONGARCH_GPR.

Thanks
Tianrui Zhao
>> +#define KVM_REG_LOONGARCH_CSR          (KVM_REG_LOONGARCH | 0x10000ULL)
>> +#define KVM_REG_LOONGARCH_KVM          (KVM_REG_LOONGARCH | 0x20000ULL)
>> +#define KVM_REG_LOONGARCH_FPU          (KVM_REG_LOONGARCH | 0x30000ULL)
>> +#define KVM_REG_LOONGARCH_MASK         (KVM_REG_LOONGARCH | 0x30000ULL)
>> +#define KVM_CSR_IDX_MASK               (0x10000 - 1)
>> +
>> +/*
>> + * KVM_REG_LOONGARCH_KVM - KVM specific control registers.
>> + */
>> +
>> +#define KVM_REG_LOONGARCH_COUNTER      (KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 3)
>> +#define KVM_REG_LOONGARCH_VCPU_RESET   (KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 4)
>> +
>> +struct kvm_debug_exit_arch {
>> +};
>> +
>> +/* for KVM_SET_GUEST_DEBUG */
>> +struct kvm_guest_debug_arch {
>> +};
>> +
>> +/* definition of registers in kvm_run */
>> +struct kvm_sync_regs {
>> +};
>> +
>> +/* dummy definition */
>> +struct kvm_sregs {
>> +};
>> +
>> +struct kvm_iocsr_entry {
>> +       __u32 addr;
>> +       __u32 pad;
>> +       __u64 data;
>> +};
>> +
>> +struct kvm_loongarch_interrupt {
>> +       /* in */
>> +       __u32 cpu;
>> +       __u32 irq;
>> +};
>> +
>> +#define KVM_NR_IRQCHIPS                1
>> +#define KVM_IRQCHIP_NUM_PINS   64
>> +#define KVM_MAX_CORES          256
>> +
>> +#endif /* __UAPI_ASM_LOONGARCH_KVM_H */
>> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
>> index 737318b1c1d9..74d9766277e7 100644
>> --- a/include/uapi/linux/kvm.h
>> +++ b/include/uapi/linux/kvm.h
>> @@ -264,6 +264,7 @@ struct kvm_xen_exit {
>>   #define KVM_EXIT_RISCV_SBI        35
>>   #define KVM_EXIT_RISCV_CSR        36
>>   #define KVM_EXIT_NOTIFY           37
>> +#define KVM_EXIT_LOONGARCH_IOCSR  38
>>
>>   /* For KVM_EXIT_INTERNAL_ERROR */
>>   /* Emulate instruction failed. */
>> @@ -336,6 +337,13 @@ struct kvm_run {
>>                          __u32 len;
>>                          __u8  is_write;
>>                  } mmio;
>> +               /* KVM_EXIT_LOONGARCH_IOCSR */
>> +               struct {
>> +                       __u64 phys_addr;
>> +                       __u8  data[8];
>> +                       __u32 len;
>> +                       __u8  is_write;
>> +               } iocsr_io;
>>                  /* KVM_EXIT_HYPERCALL */
>>                  struct {
>>                          __u64 nr;
>> @@ -1360,6 +1368,7 @@ struct kvm_dirty_tlb {
>>   #define KVM_REG_ARM64          0x6000000000000000ULL
>>   #define KVM_REG_MIPS           0x7000000000000000ULL
>>   #define KVM_REG_RISCV          0x8000000000000000ULL
>> +#define KVM_REG_LOONGARCH      0x9000000000000000ULL
>>
>>   #define KVM_REG_SIZE_SHIFT     52
>>   #define KVM_REG_SIZE_MASK      0x00f0000000000000ULL
>> --
>> 2.39.1
>>
  

Patch

diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
new file mode 100644
index 000000000000..a8ff3ef9cd55
--- /dev/null
+++ b/arch/loongarch/include/asm/kvm_host.h
@@ -0,0 +1,253 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#ifndef __ASM_LOONGARCH_KVM_HOST_H__
+#define __ASM_LOONGARCH_KVM_HOST_H__
+
+#include <linux/cpumask.h>
+#include <linux/mutex.h>
+#include <linux/hrtimer.h>
+#include <linux/interrupt.h>
+#include <linux/types.h>
+#include <linux/kvm.h>
+#include <linux/kvm_types.h>
+#include <linux/threads.h>
+#include <linux/spinlock.h>
+
+#include <asm/inst.h>
+#include <asm/loongarch.h>
+
+/* Loongarch KVM register ids */
+#define LOONGARCH_CSR_32(_R, _S)	\
+	(KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U32 | (8 * (_R) + (_S)))
+
+#define LOONGARCH_CSR_64(_R, _S)	\
+	(KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | (8 * (_R) + (_S)))
+
+#define KVM_IOC_CSRID(id)		LOONGARCH_CSR_64(id, 0)
+#define KVM_GET_IOC_CSRIDX(id)		((id & KVM_CSR_IDX_MASK) >> 3)
+
+#define KVM_MAX_VCPUS			256
+/* memory slots that does not exposed to userspace */
+#define KVM_PRIVATE_MEM_SLOTS		0
+
+#define KVM_HALT_POLL_NS_DEFAULT	500000
+
+struct kvm_vm_stat {
+	struct kvm_vm_stat_generic generic;
+};
+
+struct kvm_vcpu_stat {
+	struct kvm_vcpu_stat_generic generic;
+	u64 idle_exits;
+	u64 signal_exits;
+	u64 int_exits;
+	u64 cpucfg_exits;
+};
+
+struct kvm_arch_memory_slot {
+};
+
+struct kvm_context {
+	unsigned long vpid_cache;
+	struct kvm_vcpu *last_vcpu;
+};
+
+struct kvm_world_switch {
+	int (*guest_eentry)(void);
+	int (*enter_guest)(struct kvm_run *run, struct kvm_vcpu *vcpu);
+	unsigned long page_order;
+};
+
+struct kvm_arch {
+	/* Guest physical mm */
+	struct mm_struct gpa_mm;
+	/* Mask of CPUs needing GPA ASID flush */
+	cpumask_t asid_flush_mask;
+
+	unsigned char online_vcpus;
+	unsigned char is_migrate;
+	s64 time_offset;
+	struct kvm_context __percpu *vmcs;
+	unsigned long gpa_size;
+};
+
+#define CSR_MAX_NUMS		0x800
+
+struct loongarch_csrs {
+	unsigned long csrs[CSR_MAX_NUMS];
+};
+
+/* Resume Flags */
+#define RESUME_GUEST		1
+#define RESUME_HOST		0
+
+enum emulation_result {
+	EMULATE_DONE,		/* no further processing */
+	EMULATE_DO_MMIO,	/* kvm_run filled with MMIO request */
+	EMULATE_FAIL,		/* can't emulate this instruction */
+	EMULATE_WAIT,		/* WAIT instruction */
+	EMULATE_EXCEPT,		/* A guest exception has been generated */
+	EMULATE_DO_IOCSR,	/* handle IOCSR request */
+};
+
+#define KVM_LARCH_FPU		(0x1 << 0)
+#define KVM_LARCH_CSR		(0x1 << 1)
+
+struct kvm_vcpu_arch {
+	/*
+	 * Switch pointer-to-function type to unsigned long
+	 * for loading the value into register directly.
+	 */
+	unsigned long guest_eentry;
+	unsigned long host_eentry;
+
+	/* Pointers stored here for easy accessing from assembly code */
+	int (*handle_exit)(struct kvm_run *run, struct kvm_vcpu *vcpu);
+
+	/* Host registers preserved across guest mode execution */
+	unsigned long host_sp;
+	unsigned long host_tp;
+	unsigned long host_pgd;
+
+	/* Host CSRs are used when handling exits from guest */
+	unsigned long badi;
+	unsigned long badv;
+	unsigned long host_ecfg;
+	unsigned long host_estat;
+	unsigned long host_percpu;
+
+	/* GPRs */
+	unsigned long gprs[32];
+	unsigned long pc;
+
+	/* FPU state */
+	struct loongarch_fpu fpu FPU_ALIGN;
+	/* Which auxiliary state is loaded (KVM_LOONGARCH_AUX_*) */
+	unsigned int aux_inuse;
+
+	/* CSR state */
+	struct loongarch_csrs *csr;
+
+	/* GPR used as IO source/target */
+	u32 io_gpr;
+
+	struct hrtimer swtimer;
+	/* KVM register to control count timer */
+	u32 count_ctl;
+
+	/* Bitmask of exceptions that are pending */
+	unsigned long irq_pending;
+	/* Bitmask of pending exceptions to be cleared */
+	unsigned long irq_clear;
+
+	/* Cache for pages needed inside spinlock regions */
+	struct kvm_mmu_memory_cache mmu_page_cache;
+
+	/* vcpu's vpid */
+	u64 vpid;
+
+	/* Period of stable timer tick in ns */
+	u64 timer_period_ns;
+	/* Frequency of stable timer in Hz */
+	u64 timer_mhz;
+	/* Stable bias from the raw time */
+	u64 timer_bias;
+	/* Dynamic nanosecond bias (multiple of timer_period_ns) to avoid overflow */
+	s64 timer_dyn_bias;
+
+	ktime_t stable_ktime_saved;
+
+	u64 core_ext_ioisr[4];
+
+	/* Last CPU the vCPU state was loaded on */
+	int last_sched_cpu;
+	/* Last CPU the vCPU actually executed guest code on */
+	int last_exec_cpu;
+	/* mp state */
+	struct kvm_mp_state mp_state;
+};
+
+static inline unsigned long readl_sw_gcsr(struct loongarch_csrs *csr, int reg)
+{
+	return csr->csrs[reg];
+}
+
+static inline void writel_sw_gcsr(struct loongarch_csrs *csr, int reg,
+		unsigned long val)
+{
+	csr->csrs[reg] = val;
+}
+
+/* Helpers */
+static inline bool _kvm_guest_has_fpu(struct kvm_vcpu_arch *arch)
+{
+	return cpu_has_fpu;
+}
+
+void _kvm_init_fault(void);
+
+/* Debug: dump vcpu state */
+int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu);
+
+/* MMU handling */
+int kvm_handle_mm_fault(struct kvm_vcpu *vcpu, unsigned long badv, bool write);
+void kvm_flush_tlb_all(void);
+void _kvm_destroy_mm(struct kvm *kvm);
+pgd_t *kvm_pgd_alloc(void);
+
+#define KVM_ARCH_WANT_MMU_NOTIFIER
+int kvm_unmap_hva_range(struct kvm *kvm,
+			unsigned long start, unsigned long end, bool blockable);
+void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
+int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
+int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
+
+static inline void update_pc(struct kvm_vcpu_arch *arch)
+{
+	arch->pc += 4;
+}
+
+/**
+ * kvm_is_ifetch_fault() - Find whether a TLBL exception is due to ifetch fault.
+ * @vcpu:	Virtual CPU.
+ *
+ * Returns:	Whether the TLBL exception was likely due to an instruction
+ *		fetch fault rather than a data load fault.
+ */
+static inline bool kvm_is_ifetch_fault(struct kvm_vcpu_arch *arch)
+{
+	return arch->pc == arch->badv;
+}
+
+/* Misc */
+static inline void kvm_arch_hardware_unsetup(void) {}
+static inline void kvm_arch_sync_events(struct kvm *kvm) {}
+static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
+static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
+static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
+static inline void kvm_arch_free_memslot(struct kvm *kvm,
+				   struct kvm_memory_slot *slot) {}
+void _kvm_check_vmid(struct kvm_vcpu *vcpu);
+enum hrtimer_restart kvm_swtimer_wakeup(struct hrtimer *timer);
+int kvm_flush_tlb_gpa(struct kvm_vcpu *vcpu, unsigned long gpa);
+void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
+					const struct kvm_memory_slot *memslot);
+void kvm_init_vmcs(struct kvm *kvm);
+void kvm_vector_entry(void);
+int  kvm_enter_guest(struct kvm_run *run, struct kvm_vcpu *vcpu);
+extern const unsigned long kvm_vector_size;
+extern const unsigned long kvm_enter_guest_size;
+extern unsigned long vpid_mask;
+extern struct kvm_world_switch *kvm_loongarch_ops;
+
+#define SW_GCSR		(1 << 0)
+#define HW_GCSR		(1 << 1)
+#define INVALID_GCSR	(1 << 2)
+int get_gcsr_flag(int csr);
+extern void set_hw_gcsr(int csr_id, unsigned long val);
+#endif /* __ASM_LOONGARCH_KVM_HOST_H__ */
diff --git a/arch/loongarch/include/asm/kvm_types.h b/arch/loongarch/include/asm/kvm_types.h
new file mode 100644
index 000000000000..060647b5fe2e
--- /dev/null
+++ b/arch/loongarch/include/asm/kvm_types.h
@@ -0,0 +1,11 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#ifndef _ASM_LOONGARCH_KVM_TYPES_H
+#define _ASM_LOONGARCH_KVM_TYPES_H
+
+#define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE	4
+
+#endif /* _ASM_LOONGARCH_KVM_TYPES_H */
diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
new file mode 100644
index 000000000000..3ccadb73ad8d
--- /dev/null
+++ b/arch/loongarch/include/uapi/asm/kvm.h
@@ -0,0 +1,106 @@ 
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#ifndef __UAPI_ASM_LOONGARCH_KVM_H
+#define __UAPI_ASM_LOONGARCH_KVM_H
+
+#include <linux/types.h>
+
+/*
+ * KVM Loongarch specific structures and definitions.
+ *
+ * Some parts derived from the x86 version of this file.
+ */
+
+#define __KVM_HAVE_READONLY_MEM
+
+#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
+
+/*
+ * for KVM_GET_REGS and KVM_SET_REGS
+ */
+struct kvm_regs {
+	/* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
+	__u64 gpr[32];
+	__u64 pc;
+};
+
+/*
+ * for KVM_GET_FPU and KVM_SET_FPU
+ */
+struct kvm_fpu {
+	__u32 fcsr;
+	__u64 fcc;    /* 8x8 */
+	struct kvm_fpureg {
+		__u64 val64[4];
+	} fpr[32];
+};
+
+/*
+ * For LoongArch, we use KVM_SET_ONE_REG and KVM_GET_ONE_REG to access various
+ * registers.  The id field is broken down as follows:
+ *
+ *  bits[63..52] - As per linux/kvm.h
+ *  bits[51..32] - Must be zero.
+ *  bits[31..16] - Register set.
+ *
+ * Register set = 0: GP registers from kvm_regs (see definitions below).
+ *
+ * Register set = 1: CSR registers.
+ *
+ * Register set = 2: KVM specific registers (see definitions below).
+ *
+ * Register set = 3: FPU / SIMD registers (see definitions below).
+ *
+ * Other sets registers may be added in the future.  Each set would
+ * have its own identifier in bits[31..16].
+ */
+
+#define KVM_REG_LOONGARCH_GP		(KVM_REG_LOONGARCH | 0x00000ULL)
+#define KVM_REG_LOONGARCH_CSR		(KVM_REG_LOONGARCH | 0x10000ULL)
+#define KVM_REG_LOONGARCH_KVM		(KVM_REG_LOONGARCH | 0x20000ULL)
+#define KVM_REG_LOONGARCH_FPU		(KVM_REG_LOONGARCH | 0x30000ULL)
+#define KVM_REG_LOONGARCH_MASK		(KVM_REG_LOONGARCH | 0x30000ULL)
+#define KVM_CSR_IDX_MASK		(0x10000 - 1)
+
+/*
+ * KVM_REG_LOONGARCH_KVM - KVM specific control registers.
+ */
+
+#define KVM_REG_LOONGARCH_COUNTER	(KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 3)
+#define KVM_REG_LOONGARCH_VCPU_RESET	(KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 4)
+
+struct kvm_debug_exit_arch {
+};
+
+/* for KVM_SET_GUEST_DEBUG */
+struct kvm_guest_debug_arch {
+};
+
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
+/* dummy definition */
+struct kvm_sregs {
+};
+
+struct kvm_iocsr_entry {
+	__u32 addr;
+	__u32 pad;
+	__u64 data;
+};
+
+struct kvm_loongarch_interrupt {
+	/* in */
+	__u32 cpu;
+	__u32 irq;
+};
+
+#define KVM_NR_IRQCHIPS		1
+#define KVM_IRQCHIP_NUM_PINS	64
+#define KVM_MAX_CORES		256
+
+#endif /* __UAPI_ASM_LOONGARCH_KVM_H */
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 737318b1c1d9..74d9766277e7 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -264,6 +264,7 @@  struct kvm_xen_exit {
 #define KVM_EXIT_RISCV_SBI        35
 #define KVM_EXIT_RISCV_CSR        36
 #define KVM_EXIT_NOTIFY           37
+#define KVM_EXIT_LOONGARCH_IOCSR  38
 
 /* For KVM_EXIT_INTERNAL_ERROR */
 /* Emulate instruction failed. */
@@ -336,6 +337,13 @@  struct kvm_run {
 			__u32 len;
 			__u8  is_write;
 		} mmio;
+		/* KVM_EXIT_LOONGARCH_IOCSR */
+		struct {
+			__u64 phys_addr;
+			__u8  data[8];
+			__u32 len;
+			__u8  is_write;
+		} iocsr_io;
 		/* KVM_EXIT_HYPERCALL */
 		struct {
 			__u64 nr;
@@ -1360,6 +1368,7 @@  struct kvm_dirty_tlb {
 #define KVM_REG_ARM64		0x6000000000000000ULL
 #define KVM_REG_MIPS		0x7000000000000000ULL
 #define KVM_REG_RISCV		0x8000000000000000ULL
+#define KVM_REG_LOONGARCH	0x9000000000000000ULL
 
 #define KVM_REG_SIZE_SHIFT	52
 #define KVM_REG_SIZE_MASK	0x00f0000000000000ULL