Re: [PATCH v7 01/30] LoongArch: KVM: Add kvm related header files

From: Huacai Chen
Date: Tue Apr 18 2023 - 21:53:31 EST


Hi, Tianrui,

On Mon, Apr 17, 2023 at 5:59 PM Tianrui Zhao <zhaotianrui@xxxxxxxxxxx> 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.
>
> Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
> ---
> arch/loongarch/include/asm/cpu-features.h | 22 ++
> arch/loongarch/include/asm/kvm_host.h | 268 ++++++++++++++++++++++
> arch/loongarch/include/asm/kvm_types.h | 11 +
> arch/loongarch/include/uapi/asm/kvm.h | 107 +++++++++
> include/uapi/linux/kvm.h | 9 +
> 5 files changed, 417 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/cpu-features.h b/arch/loongarch/include/asm/cpu-features.h
> index b07974218393..345b7674a15f 100644
> --- a/arch/loongarch/include/asm/cpu-features.h
> +++ b/arch/loongarch/include/asm/cpu-features.h
> @@ -64,5 +64,27 @@
> #define cpu_has_guestid cpu_opt(LOONGARCH_CPU_GUESTID)
> #define cpu_has_hypervisor cpu_opt(LOONGARCH_CPU_HYPERVISOR)
>
> +#define cpu_has_matc_guest (cpu_data[0].guest_cfg & BIT(0))
> +#define cpu_has_matc_root (cpu_data[0].guest_cfg & BIT(1))
> +#define cpu_has_matc_nest (cpu_data[0].guest_cfg & BIT(2))
> +#define cpu_has_sitp (cpu_data[0].guest_cfg & BIT(6))
> +#define cpu_has_titp (cpu_data[0].guest_cfg & BIT(8))
> +#define cpu_has_toep (cpu_data[0].guest_cfg & BIT(10))
> +#define cpu_has_topp (cpu_data[0].guest_cfg & BIT(12))
> +#define cpu_has_torup (cpu_data[0].guest_cfg & BIT(14))
> +#define cpu_has_gcip_all (cpu_data[0].guest_cfg & BIT(16))
> +#define cpu_has_gcip_hit (cpu_data[0].guest_cfg & BIT(17))
> +#define cpu_has_gcip_secure (cpu_data[0].guest_cfg & BIT(18))
> +
> +/*
> + * Guest capabilities
> + */
> +#define cpu_guest_has_conf1 (cpu_data[0].guest.conf & BIT(1))
> +#define cpu_guest_has_conf2 (cpu_data[0].guest.conf & BIT(2))
> +#define cpu_guest_has_conf3 (cpu_data[0].guest.conf & BIT(3))
> +#define cpu_guest_has_fpu (cpu_data[0].guest.options & LOONGARCH_CPU_FPU)
> +#define cpu_guest_has_perf (cpu_data[0].guest.options & LOONGARCH_CPU_PMP)
> +#define cpu_guest_has_watch (cpu_data[0].guest.options & LOONGARCH_CPU_WATCH)
> +#define cpu_guest_has_lsx (cpu_data[0].guest.ases & LOONGARCH_ASE_LSX)
For the host cpu info, ases has combined into options, I think it is
better do the same thing for KVM.

Huacai
>
> #endif /* __ASM_CPU_FEATURES_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..bd239079b36f
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_host.h
> @@ -0,0 +1,268 @@
> +/* 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 LOONGARCH_CSRS 0x100
> +#define CSR_UCWIN_BASE 0x100
> +#define CSR_UCWIN_SIZE 0x10
> +#define CSR_DMWIN_BASE 0x180
> +#define CSR_DMWIN_SIZE 0x4
> +#define CSR_PERF_BASE 0x200
> +#define CSR_PERF_SIZE 0x8
> +#define CSR_DEBUG_BASE 0x500
> +#define CSR_DEBUG_SIZE 0x3
> +#define CSR_ALL_SIZE 0x800
> +
> +struct loongarch_csrs {
> + unsigned long csrs[CSR_ALL_SIZE];
> +};
> +
> +/* 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_NR_MEM_OBJS 4
> +#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 access from assembly code. */
> + int (*handle_exit)(struct kvm_run *run, struct kvm_vcpu *vcpu);
> +
> + /* Host registers preserved across guest mode execution */
> + unsigned long host_stack;
> + unsigned long host_gp;
> + unsigned long host_pgd;
> + unsigned long host_pgdhi;
> + unsigned long host_entryhi;
> +
> + /* Host CSR registers used when handling exits from guest */
> + unsigned long badv;
> + unsigned long host_estat;
> + unsigned long badi;
> + unsigned long host_ecfg;
> + 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;
> + /* Count timer control KVM register */
> + 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 some mmu 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;
> + /* 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) to avoid overflow */
> + s64 timer_dyn_bias;
> + /* Save ktime */
> + 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)
> +{
> + if (arch->pc == arch->badv)
> + return true;
> +
> + return false;
> +}
> +
> +/* 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, int cpu);
> +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)
> +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..074d86ba532c
> --- /dev/null
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -0,0 +1,107 @@
> +/* 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;
> + __u32 none;
> + __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 d77aef872a0a..d14fde87ae35 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;
> @@ -1354,6 +1362,7 @@ 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
> --
> 2.31.1
>
>