diff options
| author | Anup Patel <anup.patel@wdc.com> | 2021-09-27 17:10:06 +0530 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2021-10-04 15:51:47 +0530 |
| commit | 9f7013265112a92340cef5debec8d02ec8d1de06 (patch) | |
| tree | 4f77126d24e2124aa992f910012f49ce260602fa /arch/riscv/kernel/asm-offsets.c | |
| parent | 34bde9d8b9e6e5249db3c07cf1ebfe75c23c671c (diff) | |
RISC-V: KVM: Handle MMIO exits for VCPU
We will get stage2 page faults whenever Guest/VM access SW emulated
MMIO device or unmapped Guest RAM.
This patch implements MMIO read/write emulation by extracting MMIO
details from the trapped load/store instruction and forwarding the
MMIO read/write to user-space. The actual MMIO emulation will happen
in user-space and KVM kernel module will only take care of register
updates before resuming the trapped VCPU.
The handling for stage2 page faults for unmapped Guest RAM will be
implemeted by a separate patch later.
[jiangyifei: ioeventfd and in-kernel mmio device support]
Signed-off-by: Yifei Jiang <jiangyifei@huawei.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv/kernel/asm-offsets.c')
| -rw-r--r-- | arch/riscv/kernel/asm-offsets.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c index 2fac70303341..91c77555d914 100644 --- a/arch/riscv/kernel/asm-offsets.c +++ b/arch/riscv/kernel/asm-offsets.c @@ -189,6 +189,12 @@ void asm_offsets(void) OFFSET(KVM_ARCH_HOST_STVEC, kvm_vcpu_arch, host_stvec); OFFSET(KVM_ARCH_HOST_SCOUNTEREN, kvm_vcpu_arch, host_scounteren); + OFFSET(KVM_ARCH_TRAP_SEPC, kvm_cpu_trap, sepc); + OFFSET(KVM_ARCH_TRAP_SCAUSE, kvm_cpu_trap, scause); + OFFSET(KVM_ARCH_TRAP_STVAL, kvm_cpu_trap, stval); + OFFSET(KVM_ARCH_TRAP_HTVAL, kvm_cpu_trap, htval); + OFFSET(KVM_ARCH_TRAP_HTINST, kvm_cpu_trap, htinst); + /* * THREAD_{F,X}* might be larger than a S-type offset can handle, but * these are used in performance-sensitive assembly so we can't resort |