diff options
author | Anup Patel <anup.patel@wdc.com> | 2021-09-27 14:40:01 +0300 |
---|---|---|
committer | Anup Patel <anup@brainfault.org> | 2021-10-04 13:10:08 +0300 |
commit | 99cdc6c18c2d815e940e81b9b477d469bdd41788 (patch) | |
tree | 5f279c009abe607b00a37949bd1c9f98b864541c | |
parent | 3f2401f47d29d669e2cb137709d10dd4c156a02f (diff) | |
download | linux-99cdc6c18c2d815e940e81b9b477d469bdd41788.tar.xz |
RISC-V: Add initial skeletal KVM support
This patch adds initial skeletal KVM RISC-V support which has:
1. A simple implementation of arch specific VM functions
except kvm_vm_ioctl_get_dirty_log() which will implemeted
in-future as part of stage2 page loging.
2. Stubs of required arch specific VCPU functions except
kvm_arch_vcpu_ioctl_run() which is semi-complete and
extended by subsequent patches.
3. Stubs for required arch specific stage2 MMU functions.
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>
-rw-r--r-- | arch/riscv/Kconfig | 1 | ||||
-rw-r--r-- | arch/riscv/Makefile | 1 | ||||
-rw-r--r-- | arch/riscv/include/asm/kvm_host.h | 84 | ||||
-rw-r--r-- | arch/riscv/include/asm/kvm_types.h | 7 | ||||
-rw-r--r-- | arch/riscv/include/uapi/asm/kvm.h | 47 | ||||
-rw-r--r-- | arch/riscv/kvm/Kconfig | 33 | ||||
-rw-r--r-- | arch/riscv/kvm/Makefile | 13 | ||||
-rw-r--r-- | arch/riscv/kvm/main.c | 95 | ||||
-rw-r--r-- | arch/riscv/kvm/mmu.c | 80 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu.c | 314 | ||||
-rw-r--r-- | arch/riscv/kvm/vcpu_exit.c | 35 | ||||
-rw-r--r-- | arch/riscv/kvm/vm.c | 95 |
12 files changed, 805 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 301a54233c7e..f5fe8a7f0e24 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -562,4 +562,5 @@ source "kernel/power/Kconfig" endmenu +source "arch/riscv/kvm/Kconfig" source "drivers/firmware/Kconfig" diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 0eb4568fbd29..58c1a28e20bb 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -100,6 +100,7 @@ endif head-y := arch/riscv/kernel/head.o core-$(CONFIG_RISCV_ERRATA_ALTERNATIVE) += arch/riscv/errata/ +core-$(CONFIG_KVM) += arch/riscv/kvm/ libs-y += arch/riscv/lib/ libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h new file mode 100644 index 000000000000..08a8f53bf814 --- /dev/null +++ b/arch/riscv/include/asm/kvm_host.h @@ -0,0 +1,84 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#ifndef __RISCV_KVM_HOST_H__ +#define __RISCV_KVM_HOST_H__ + +#include <linux/types.h> +#include <linux/kvm.h> +#include <linux/kvm_types.h> + +#ifdef CONFIG_64BIT +#define KVM_MAX_VCPUS (1U << 16) +#else +#define KVM_MAX_VCPUS (1U << 9) +#endif + +#define KVM_HALT_POLL_NS_DEFAULT 500000 + +#define KVM_VCPU_MAX_FEATURES 0 + +#define KVM_REQ_SLEEP \ + KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) +#define KVM_REQ_VCPU_RESET KVM_ARCH_REQ(1) + +struct kvm_vm_stat { + struct kvm_vm_stat_generic generic; +}; + +struct kvm_vcpu_stat { + struct kvm_vcpu_stat_generic generic; + u64 ecall_exit_stat; + u64 wfi_exit_stat; + u64 mmio_exit_user; + u64 mmio_exit_kernel; + u64 exits; +}; + +struct kvm_arch_memory_slot { +}; + +struct kvm_arch { + /* stage2 page table */ + pgd_t *pgd; + phys_addr_t pgd_phys; +}; + +struct kvm_cpu_trap { + unsigned long sepc; + unsigned long scause; + unsigned long stval; + unsigned long htval; + unsigned long htinst; +}; + +struct kvm_vcpu_arch { + /* Don't run the VCPU (blocked) */ + bool pause; + + /* SRCU lock index for in-kernel run loop */ + int srcu_idx; +}; + +static inline void kvm_arch_hardware_unsetup(void) {} +static inline void kvm_arch_sync_events(struct kvm *kvm) {} +static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} +static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {} + +void kvm_riscv_stage2_flush_cache(struct kvm_vcpu *vcpu); +int kvm_riscv_stage2_alloc_pgd(struct kvm *kvm); +void kvm_riscv_stage2_free_pgd(struct kvm *kvm); +void kvm_riscv_stage2_update_hgatp(struct kvm_vcpu *vcpu); + +int kvm_riscv_vcpu_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run); +int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_cpu_trap *trap); + +static inline void __kvm_riscv_switch_to(struct kvm_vcpu_arch *vcpu_arch) {} + +#endif /* __RISCV_KVM_HOST_H__ */ diff --git a/arch/riscv/include/asm/kvm_types.h b/arch/riscv/include/asm/kvm_types.h new file mode 100644 index 000000000000..e476b404eb67 --- /dev/null +++ b/arch/riscv/include/asm/kvm_types.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_RISCV_KVM_TYPES_H +#define _ASM_RISCV_KVM_TYPES_H + +#define KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE 40 + +#endif /* _ASM_RISCV_KVM_TYPES_H */ diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h new file mode 100644 index 000000000000..984d041a3e3b --- /dev/null +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#ifndef __LINUX_KVM_RISCV_H +#define __LINUX_KVM_RISCV_H + +#ifndef __ASSEMBLY__ + +#include <linux/types.h> +#include <asm/ptrace.h> + +#define __KVM_HAVE_READONLY_MEM + +#define KVM_COALESCED_MMIO_PAGE_OFFSET 1 + +/* for KVM_GET_REGS and KVM_SET_REGS */ +struct kvm_regs { +}; + +/* for KVM_GET_FPU and KVM_SET_FPU */ +struct kvm_fpu { +}; + +/* KVM Debug exit structure */ +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 { +}; + +#endif + +#endif /* __LINUX_KVM_RISCV_H */ diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig new file mode 100644 index 000000000000..88edd477b3a8 --- /dev/null +++ b/arch/riscv/kvm/Kconfig @@ -0,0 +1,33 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# KVM configuration +# + +source "virt/kvm/Kconfig" + +menuconfig VIRTUALIZATION + bool "Virtualization" + help + Say Y here to get to see options for using your Linux host to run + other operating systems inside virtual machines (guests). + This option alone does not add any kernel code. + + If you say N, all options in this submenu will be skipped and + disabled. + +if VIRTUALIZATION + +config KVM + tristate "Kernel-based Virtual Machine (KVM) support (EXPERIMENTAL)" + depends on RISCV_SBI && MMU + select PREEMPT_NOTIFIERS + select ANON_INODES + select KVM_MMIO + select HAVE_KVM_VCPU_ASYNC_IOCTL + select SRCU + help + Support hosting virtualized guest machines. + + If unsure, say N. + +endif # VIRTUALIZATION diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile new file mode 100644 index 000000000000..4732094391bf --- /dev/null +++ b/arch/riscv/kvm/Makefile @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for RISC-V KVM support +# + +ccflags-y += -I $(srctree)/$(src) + +KVM := ../../../virt/kvm + +obj-$(CONFIG_KVM) += kvm.o + +kvm-y += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/binary_stats.o \ + main.o vm.o mmu.o vcpu.o vcpu_exit.o diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c new file mode 100644 index 000000000000..47926f0c175d --- /dev/null +++ b/arch/riscv/kvm/main.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/hwcap.h> +#include <asm/sbi.h> + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} + +int kvm_arch_check_processor_compat(void *opaque) +{ + return 0; +} + +int kvm_arch_hardware_setup(void *opaque) +{ + return 0; +} + +int kvm_arch_hardware_enable(void) +{ + unsigned long hideleg, hedeleg; + + hedeleg = 0; + hedeleg |= (1UL << EXC_INST_MISALIGNED); + hedeleg |= (1UL << EXC_BREAKPOINT); + hedeleg |= (1UL << EXC_SYSCALL); + hedeleg |= (1UL << EXC_INST_PAGE_FAULT); + hedeleg |= (1UL << EXC_LOAD_PAGE_FAULT); + hedeleg |= (1UL << EXC_STORE_PAGE_FAULT); + csr_write(CSR_HEDELEG, hedeleg); + + hideleg = 0; + hideleg |= (1UL << IRQ_VS_SOFT); + hideleg |= (1UL << IRQ_VS_TIMER); + hideleg |= (1UL << IRQ_VS_EXT); + csr_write(CSR_HIDELEG, hideleg); + + csr_write(CSR_HCOUNTEREN, -1UL); + + csr_write(CSR_HVIP, 0); + + return 0; +} + +void kvm_arch_hardware_disable(void) +{ + csr_write(CSR_HEDELEG, 0); + csr_write(CSR_HIDELEG, 0); +} + +int kvm_arch_init(void *opaque) +{ + if (!riscv_isa_extension_available(NULL, h)) { + kvm_info("hypervisor extension not available\n"); + return -ENODEV; + } + + if (sbi_spec_is_0_1()) { + kvm_info("require SBI v0.2 or higher\n"); + return -ENODEV; + } + + if (sbi_probe_extension(SBI_EXT_RFENCE) <= 0) { + kvm_info("require SBI RFENCE extension\n"); + return -ENODEV; + } + + kvm_info("hypervisor extension available\n"); + + return 0; +} + +void kvm_arch_exit(void) +{ +} + +static int riscv_kvm_init(void) +{ + return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); +} +module_init(riscv_kvm_init); diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c new file mode 100644 index 000000000000..abfd2b22fa8e --- /dev/null +++ b/arch/riscv/kvm/mmu.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/hugetlb.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/kvm_host.h> +#include <linux/sched/signal.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) +{ +} + +void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free) +{ +} + +void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) +{ +} + +void kvm_arch_flush_shadow_all(struct kvm *kvm) +{ + /* TODO: */ +} + +void kvm_arch_flush_shadow_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ +} + +void kvm_arch_commit_memory_region(struct kvm *kvm, + const struct kvm_userspace_memory_region *mem, + struct kvm_memory_slot *old, + const struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + /* TODO: */ +} + +int kvm_arch_prepare_memory_region(struct kvm *kvm, + struct kvm_memory_slot *memslot, + const struct kvm_userspace_memory_region *mem, + enum kvm_mr_change change) +{ + /* TODO: */ + return 0; +} + +void kvm_riscv_stage2_flush_cache(struct kvm_vcpu *vcpu) +{ + /* TODO: */ +} + +int kvm_riscv_stage2_alloc_pgd(struct kvm *kvm) +{ + /* TODO: */ + return 0; +} + +void kvm_riscv_stage2_free_pgd(struct kvm *kvm) +{ + /* TODO: */ +} + +void kvm_riscv_stage2_update_hgatp(struct kvm_vcpu *vcpu) +{ + /* TODO: */ +} diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c new file mode 100644 index 000000000000..810b7ef30c0b --- /dev/null +++ b/arch/riscv/kvm/vcpu.c @@ -0,0 +1,314 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kdebug.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/sched/signal.h> +#include <linux/fs.h> +#include <linux/kvm_host.h> +#include <asm/csr.h> +#include <asm/delay.h> +#include <asm/hwcap.h> + +const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { + KVM_GENERIC_VCPU_STATS(), + STATS_DESC_COUNTER(VCPU, ecall_exit_stat), + STATS_DESC_COUNTER(VCPU, wfi_exit_stat), + STATS_DESC_COUNTER(VCPU, mmio_exit_user), + STATS_DESC_COUNTER(VCPU, mmio_exit_kernel), + STATS_DESC_COUNTER(VCPU, exits) +}; + +const struct kvm_stats_header kvm_vcpu_stats_header = { + .name_size = KVM_STATS_NAME_SIZE, + .num_desc = ARRAY_SIZE(kvm_vcpu_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_vcpu_stats_desc), +}; + +int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) +{ + return 0; +} + +int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return 0; +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ +} + +int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return 0; +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + /* TODO: */ +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return 0; +} + +void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) +{ +} + +void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) +{ +} + +int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return 0; +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return 0; +} + +bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) +{ + /* TODO: */ + return false; +} + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +long kvm_arch_vcpu_async_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + /* TODO; */ + return -ENOIOCTLCMD; +} + +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + /* TODO: */ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, + struct kvm_translation *tr) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + /* TODO: */ + return 0; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + /* TODO: */ + return 0; +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + /* TODO; To be implemented later. */ + return -EINVAL; +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + /* TODO: */ + + kvm_riscv_stage2_update_hgatp(vcpu); +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + /* TODO: */ +} + +static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu) +{ + /* TODO: */ +} + +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) +{ + int ret; + struct kvm_cpu_trap trap; + struct kvm_run *run = vcpu->run; + + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + /* Process MMIO value returned from user-space */ + if (run->exit_reason == KVM_EXIT_MMIO) { + ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run); + if (ret) { + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + return ret; + } + } + + if (run->immediate_exit) { + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + return -EINTR; + } + + vcpu_load(vcpu); + + kvm_sigset_activate(vcpu); + + ret = 1; + run->exit_reason = KVM_EXIT_UNKNOWN; + while (ret > 0) { + /* Check conditions before entering the guest */ + cond_resched(); + + kvm_riscv_check_vcpu_requests(vcpu); + + preempt_disable(); + + local_irq_disable(); + + /* + * Exit if we have a signal pending so that we can deliver + * the signal to user space. + */ + if (signal_pending(current)) { + ret = -EINTR; + run->exit_reason = KVM_EXIT_INTR; + } + + /* + * Ensure we set mode to IN_GUEST_MODE after we disable + * interrupts and before the final VCPU requests check. + * See the comment in kvm_vcpu_exiting_guest_mode() and + * Documentation/virtual/kvm/vcpu-requests.rst + */ + vcpu->mode = IN_GUEST_MODE; + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + smp_mb__after_srcu_read_unlock(); + + if (ret <= 0 || + kvm_request_pending(vcpu)) { + vcpu->mode = OUTSIDE_GUEST_MODE; + local_irq_enable(); + preempt_enable(); + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + continue; + } + + guest_enter_irqoff(); + + __kvm_riscv_switch_to(&vcpu->arch); + + vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->stat.exits++; + + /* + * Save SCAUSE, STVAL, HTVAL, and HTINST because we might + * get an interrupt between __kvm_riscv_switch_to() and + * local_irq_enable() which can potentially change CSRs. + */ + trap.sepc = 0; + trap.scause = csr_read(CSR_SCAUSE); + trap.stval = csr_read(CSR_STVAL); + trap.htval = csr_read(CSR_HTVAL); + trap.htinst = csr_read(CSR_HTINST); + + /* + * We may have taken a host interrupt in VS/VU-mode (i.e. + * while executing the guest). This interrupt is still + * pending, as we haven't serviced it yet! + * + * We're now back in HS-mode with interrupts disabled + * so enabling the interrupts now will have the effect + * of taking the interrupt again, in HS-mode this time. + */ + local_irq_enable(); + + /* + * We do local_irq_enable() before calling guest_exit() so + * that if a timer interrupt hits while running the guest + * we account that tick as being spent in the guest. We + * enable preemption after calling guest_exit() so that if + * we get preempted we make sure ticks after that is not + * counted as guest time. + */ + guest_exit(); + + preempt_enable(); + + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + ret = kvm_riscv_vcpu_exit(vcpu, run, &trap); + } + + kvm_sigset_deactivate(vcpu); + + vcpu_put(vcpu); + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + + return ret; +} diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c new file mode 100644 index 000000000000..4484e9200fe4 --- /dev/null +++ b/arch/riscv/kvm/vcpu_exit.c @@ -0,0 +1,35 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> + +/** + * kvm_riscv_vcpu_mmio_return -- Handle MMIO loads after user space emulation + * or in-kernel IO emulation + * + * @vcpu: The VCPU pointer + * @run: The VCPU run struct containing the mmio data + */ +int kvm_riscv_vcpu_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* TODO: */ + return 0; +} + +/* + * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on + * proper exit to userspace. + */ +int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, + struct kvm_cpu_trap *trap) +{ + /* TODO: */ + return 0; +} diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c new file mode 100644 index 000000000000..22490803d904 --- /dev/null +++ b/arch/riscv/kvm/vm.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/kvm_host.h> + +const struct _kvm_stats_desc kvm_vm_stats_desc[] = { + KVM_GENERIC_VM_STATS() +}; +static_assert(ARRAY_SIZE(kvm_vm_stats_desc) == + sizeof(struct kvm_vm_stat) / sizeof(u64)); + +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), +}; + +int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) +{ + /* TODO: To be added later. */ + return -EOPNOTSUPP; +} + +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) +{ + int r; + + r = kvm_riscv_stage2_alloc_pgd(kvm); + if (r) + return r; + + return 0; +} + +void kvm_arch_destroy_vm(struct kvm *kvm) +{ + int i; + + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + if (kvm->vcpus[i]) { + kvm_vcpu_destroy(kvm->vcpus[i]); + kvm->vcpus[i] = NULL; + } + } + atomic_set(&kvm->online_vcpus, 0); +} + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) +{ + int r; + + switch (ext) { + case KVM_CAP_DEVICE_CTRL: + case KVM_CAP_USER_MEMORY: + case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: + case KVM_CAP_ONE_REG: + case KVM_CAP_READONLY_MEM: + case KVM_CAP_MP_STATE: + case KVM_CAP_IMMEDIATE_EXIT: + r = 1; + break; + case KVM_CAP_NR_VCPUS: + r = num_online_cpus(); + break; + case KVM_CAP_MAX_VCPUS: + r = KVM_MAX_VCPUS; + break; + case KVM_CAP_NR_MEMSLOTS: + r = KVM_USER_MEM_SLOTS; + break; + default: + r = 0; + break; + } + + return r; +} + +long kvm_arch_vm_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} |