arch/loongarch/kvm/vm.c
Source file repositories/reference/linux-study-clean/arch/loongarch/kvm/vm.c
File Facts
- System
- Linux kernel
- Corpus path
arch/loongarch/kvm/vm.c- Extension
.c- Size
- 5592 bytes
- Lines
- 213
- Domain
- Architecture Layer
- Bucket
- arch/loongarch
- Inferred role
- Architecture Layer: implementation source
- Status
- source implementation candidate
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kvm_host.hasm/kvm_mmu.hasm/kvm_vcpu.hasm/kvm_csr.hasm/kvm_eiointc.hasm/kvm_pch_pic.h
Detected Declarations
function kvm_vm_init_featuresfunction kvm_arch_init_vmfunction kvm_arch_destroy_vmfunction kvm_vm_ioctl_check_extensionfunction kvm_vm_feature_has_attrfunction kvm_vm_has_attrfunction kvm_arch_vm_ioctlfunction kvm_vm_ioctl_irq_linefunction kvm_arch_irqchip_in_kernel
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020-2023 Loongson Technology Corporation Limited
*/
#include <linux/kvm_host.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_vcpu.h>
#include <asm/kvm_csr.h>
#include <asm/kvm_eiointc.h>
#include <asm/kvm_pch_pic.h>
const struct kvm_stats_desc kvm_vm_stats_desc[] = {
KVM_GENERIC_VM_STATS(),
STATS_DESC_ICOUNTER(VM, pages),
STATS_DESC_ICOUNTER(VM, hugepages),
};
const struct kvm_stats_header kvm_vm_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
.id_offset = sizeof(struct kvm_stats_header),
.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
sizeof(kvm_vm_stats_desc),
};
static void kvm_vm_init_features(struct kvm *kvm)
{
unsigned long val;
if (cpu_has_lsx)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_LSX);
if (cpu_has_lasx)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_LASX);
if (cpu_has_lbt_x86)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_X86BT);
if (cpu_has_lbt_arm)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_ARMBT);
if (cpu_has_lbt_mips)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_MIPSBT);
if (cpu_has_ptw)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_PTW);
if (cpu_has_msgint)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_MSGINT);
val = read_csr_gcfg();
if (val & CSR_GCFG_GPMP)
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_PMU);
/* Enable all PV features by default */
kvm->arch.pv_features |= BIT(KVM_FEATURE_IPI);
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_PV_IPI);
if (kvm_pvtime_supported()) {
kvm->arch.pv_features |= BIT(KVM_FEATURE_PREEMPT);
kvm->arch.pv_features |= BIT(KVM_FEATURE_STEAL_TIME);
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_PV_PREEMPT);
kvm->arch.kvm_features |= BIT(KVM_LOONGARCH_VM_FEAT_PV_STEALTIME);
}
}
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
int i;
/* Allocate page table to map GPA -> RPA */
kvm->arch.pgd = kvm_pgd_alloc();
if (!kvm->arch.pgd)
return -ENOMEM;
kvm->arch.phyid_map = kvzalloc_obj(struct kvm_phyid_map,
GFP_KERNEL_ACCOUNT);
if (!kvm->arch.phyid_map) {
free_page((unsigned long)kvm->arch.pgd);
kvm->arch.pgd = NULL;
return -ENOMEM;
}
spin_lock_init(&kvm->arch.phyid_map_lock);
kvm_init_vmcs(kvm);
kvm_vm_init_features(kvm);
/*
* cpu_vabits means user address space only (a half of total).
* GPA size of VM is the same with the size of user address space.
*/
kvm->arch.gpa_size = BIT(cpu_vabits);
kvm->arch.root_level = CONFIG_PGTABLE_LEVELS - 1;
kvm->arch.invalid_ptes[0] = 0;
kvm->arch.invalid_ptes[1] = (unsigned long)invalid_pte_table;
Annotation
- Immediate include surface: `linux/kvm_host.h`, `asm/kvm_mmu.h`, `asm/kvm_vcpu.h`, `asm/kvm_csr.h`, `asm/kvm_eiointc.h`, `asm/kvm_pch_pic.h`.
- Detected declarations: `function kvm_vm_init_features`, `function kvm_arch_init_vm`, `function kvm_arch_destroy_vm`, `function kvm_vm_ioctl_check_extension`, `function kvm_vm_feature_has_attr`, `function kvm_vm_has_attr`, `function kvm_arch_vm_ioctl`, `function kvm_vm_ioctl_irq_line`, `function kvm_arch_irqchip_in_kernel`.
- Atlas domain: Architecture Layer / arch/loongarch.
- Implementation status: source implementation candidate.
- This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.