arch/riscv/kvm/aia.c
Source file repositories/reference/linux-study-clean/arch/riscv/kvm/aia.c
File Facts
- System
- Linux kernel
- Corpus path
arch/riscv/kvm/aia.c- Extension
.c- Size
- 17461 bytes
- Lines
- 701
- Domain
- Architecture Layer
- Bucket
- arch/riscv
- 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.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Touches IRQ or DMA behavior; this matters for the representative real-device path.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/bitops.hlinux/irq.hlinux/irqchip/riscv-imsic.hlinux/irqdomain.hlinux/kvm_host.hlinux/nospec.hlinux/percpu.hlinux/spinlock.hasm/cpufeature.hasm/kvm_nacl.h
Detected Declarations
struct aia_hgei_controlfunction aia_hvictl_valuefunction kvm_riscv_vcpu_aia_flush_interruptsfunction kvm_riscv_vcpu_aia_sync_interruptsfunction kvm_riscv_vcpu_aia_has_interruptsfunction kvm_riscv_vcpu_aia_update_hvipfunction kvm_riscv_vcpu_aia_loadfunction kvm_riscv_vcpu_aia_putfunction kvm_riscv_vcpu_aia_get_csrfunction kvm_riscv_vcpu_aia_set_csrfunction kvm_riscv_vcpu_aia_rmw_topeifunction aia_get_iprio8function aia_set_iprio8function aia_rmw_ipriofunction kvm_riscv_vcpu_aia_rmw_iregfunction kvm_riscv_aia_alloc_hgeifunction kvm_riscv_aia_free_hgeifunction hgei_interruptfunction for_each_set_bitfunction aia_hgei_initfunction aia_hgei_exitfunction kvm_riscv_aia_enablefunction kvm_riscv_aia_disablefunction kvm_riscv_aia_initfunction kvm_riscv_aia_exit
Annotated Snippet
struct aia_hgei_control {
raw_spinlock_t lock;
bool free_bitmap_initialized;
unsigned long free_bitmap;
struct kvm_vcpu *owners[BITS_PER_LONG];
unsigned int nr_hgei;
};
static DEFINE_PER_CPU(struct aia_hgei_control, aia_hgei);
static int hgei_parent_irq;
atomic_t kvm_riscv_aia_nr_hgei;
unsigned int kvm_riscv_aia_max_ids;
DEFINE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
static inline unsigned long aia_hvictl_value(bool ext_irq_pending)
{
unsigned long hvictl;
/*
* HVICTL.IID == 9 and HVICTL.IPRIO == 0 represents
* no interrupt in HVICTL.
*/
hvictl = (IRQ_S_EXT << HVICTL_IID_SHIFT) & HVICTL_IID;
hvictl |= ext_irq_pending;
return hvictl;
}
#ifdef CONFIG_32BIT
void kvm_riscv_vcpu_aia_flush_interrupts(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_aia_csr *csr = &vcpu->arch.aia_context.guest_csr;
unsigned long mask, val;
if (!kvm_riscv_aia_available())
return;
if (READ_ONCE(vcpu->arch.irqs_pending_mask[1])) {
mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[1], 0);
val = READ_ONCE(vcpu->arch.irqs_pending[1]) & mask;
csr->hviph &= ~mask;
csr->hviph |= val;
}
}
void kvm_riscv_vcpu_aia_sync_interrupts(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_aia_csr *csr = &vcpu->arch.aia_context.guest_csr;
if (kvm_riscv_aia_available())
csr->vsieh = ncsr_read(CSR_VSIEH);
}
#endif
bool kvm_riscv_vcpu_aia_has_interrupts(struct kvm_vcpu *vcpu, u64 mask)
{
unsigned long seip;
if (!kvm_riscv_aia_available())
return false;
#ifdef CONFIG_32BIT
if (READ_ONCE(vcpu->arch.irqs_pending[1]) &
(vcpu->arch.aia_context.guest_csr.vsieh & upper_32_bits(mask)))
return true;
#endif
seip = vcpu->arch.guest_csr.vsie;
seip &= (unsigned long)mask;
seip &= BIT(IRQ_S_EXT);
if (!kvm_riscv_aia_initialized(vcpu->kvm) || !seip)
return false;
return kvm_riscv_vcpu_aia_imsic_has_interrupt(vcpu);
}
void kvm_riscv_vcpu_aia_update_hvip(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
if (!kvm_riscv_aia_available())
return;
#ifdef CONFIG_32BIT
ncsr_write(CSR_HVIPH, vcpu->arch.aia_context.guest_csr.hviph);
#endif
ncsr_write(CSR_HVICTL, aia_hvictl_value(!!(csr->hvip & BIT(IRQ_VS_EXT))));
}
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/bitops.h`, `linux/irq.h`, `linux/irqchip/riscv-imsic.h`, `linux/irqdomain.h`, `linux/kvm_host.h`, `linux/nospec.h`, `linux/percpu.h`.
- Detected declarations: `struct aia_hgei_control`, `function aia_hvictl_value`, `function kvm_riscv_vcpu_aia_flush_interrupts`, `function kvm_riscv_vcpu_aia_sync_interrupts`, `function kvm_riscv_vcpu_aia_has_interrupts`, `function kvm_riscv_vcpu_aia_update_hvip`, `function kvm_riscv_vcpu_aia_load`, `function kvm_riscv_vcpu_aia_put`, `function kvm_riscv_vcpu_aia_get_csr`, `function kvm_riscv_vcpu_aia_set_csr`.
- Atlas domain: Architecture Layer / arch/riscv.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
- IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.
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.