Implement LoongArch kvm module init, module exit interface,
using kvm context to save the vpid info and vcpu world switch
interface pointer.
Reviewed-by: Bibo Mao <maobibo@xxxxxxxxxxx>
Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
---
arch/loongarch/kvm/main.c | 367 ++++++++++++++++++++++++++++++++++++++
1 file changed, 367 insertions(+)
create mode 100644 arch/loongarch/kvm/main.c
diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
new file mode 100644
index 0000000000..0deb9273d8
--- /dev/null
+++ b/arch/loongarch/kvm/main.c
@@ -0,0 +1,367 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kvm_host.h>
+#include <asm/cacheflush.h>
+#include <asm/cpufeature.h>
+#include <asm/kvm_csr.h>
+#include "trace.h"
+
+static struct kvm_context __percpu *vmcs;
+struct kvm_world_switch *kvm_loongarch_ops;
+unsigned long vpid_mask;
+static int gcsr_flag[CSR_MAX_NUMS];
+
+int get_gcsr_flag(int csr)
+{
+ if (csr < CSR_MAX_NUMS)
+ return gcsr_flag[csr];
+
+ return INVALID_GCSR;
+}
+
+static inline void set_gcsr_sw_flag(int csr)
+{
+ if (csr < CSR_MAX_NUMS)
+ gcsr_flag[csr] |= SW_GCSR;
+}
+
+static inline void set_gcsr_hw_flag(int csr)
+{
+ if (csr < CSR_MAX_NUMS)
+ gcsr_flag[csr] |= HW_GCSR;
+}
+
+/*
+ * The default value of gcsr_flag[CSR] is 0, and we use this
+ * function to set the flag to 1(SW_GCSR) or 2(HW_GCSR) if the
+ * gcsr is software or hardware. It will be used by get/set_gcsr,
+ * if gcsr_flag is HW we should use gcsrrd/gcsrwr to access it,
+ * else use sw csr to emulate it.
+ */
+static void kvm_init_gcsr_flag(void)
+{
+ set_gcsr_hw_flag(LOONGARCH_CSR_CRMD);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PRMD);
+ set_gcsr_hw_flag(LOONGARCH_CSR_EUEN);
+ set_gcsr_hw_flag(LOONGARCH_CSR_MISC);
+ set_gcsr_hw_flag(LOONGARCH_CSR_ECFG);
+ set_gcsr_hw_flag(LOONGARCH_CSR_ESTAT);
+ set_gcsr_hw_flag(LOONGARCH_CSR_ERA);
+ set_gcsr_hw_flag(LOONGARCH_CSR_BADV);
+ set_gcsr_hw_flag(LOONGARCH_CSR_BADI);
+ set_gcsr_hw_flag(LOONGARCH_CSR_EENTRY);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBIDX);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBEHI);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBELO0);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBELO1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_ASID);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PGDL);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PGDH);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PWCTL0);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PWCTL1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_STLBPGSIZE);
+ set_gcsr_hw_flag(LOONGARCH_CSR_RVACFG);
+ set_gcsr_hw_flag(LOONGARCH_CSR_CPUID);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PRCFG1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PRCFG2);
+ set_gcsr_hw_flag(LOONGARCH_CSR_PRCFG3);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS0);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS2);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS3);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS4);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS5);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS6);
+ set_gcsr_hw_flag(LOONGARCH_CSR_KS7);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TMID);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TCFG);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TVAL);
+ set_gcsr_hw_flag(LOONGARCH_CSR_CNTC);
+ set_gcsr_hw_flag(LOONGARCH_CSR_LLBCTL);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRENTRY);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRBADV);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRERA);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRSAVE);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRELO0);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRELO1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBREHI);
+ set_gcsr_hw_flag(LOONGARCH_CSR_TLBRPRMD);
+ set_gcsr_hw_flag(LOONGARCH_CSR_DMWIN0);
+ set_gcsr_hw_flag(LOONGARCH_CSR_DMWIN1);
+ set_gcsr_hw_flag(LOONGARCH_CSR_DMWIN2);
+ set_gcsr_hw_flag(LOONGARCH_CSR_DMWIN3);
+ set_gcsr_hw_flag(LOONGARCH_CSR_MWPS);
+ set_gcsr_hw_flag(LOONGARCH_CSR_FWPS);
+
+ set_gcsr_sw_flag(LOONGARCH_CSR_IMPCTL1);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IMPCTL2);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRCTL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRINFO1);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRINFO2);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRENTRY);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRERA);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MERRSAVE);
+ set_gcsr_sw_flag(LOONGARCH_CSR_CTAG);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DEBUG);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DERA);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DESAVE);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PRCFG1);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PRCFG2);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PRCFG3);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PGD);
+ set_gcsr_sw_flag(LOONGARCH_CSR_TINTCLR);
+
+ set_gcsr_sw_flag(LOONGARCH_CSR_FWPS);
+ set_gcsr_sw_flag(LOONGARCH_CSR_FWPC);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MWPS);
+ set_gcsr_sw_flag(LOONGARCH_CSR_MWPC);
+
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB0ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB0MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB0CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB0ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB1ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB1MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB1CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB1ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB2ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB2MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB2CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB2ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB3ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB3MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB3CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB3ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB4ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB4MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB4CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB4ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB5ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB5MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB5CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB5ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB6ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB6MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB6CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB6ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB7ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB7MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB7CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_DB7ASID);
+
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB0ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB0MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB0CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB0ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB1ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB1MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB1CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB1ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB2ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB2MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB2CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB2ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB3ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB3MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB3CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB3ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB4ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB4MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB4CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB4ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB5ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB5MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB5CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB5ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB6ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB6MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB6CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB6ASID);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB7ADDR);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB7MASK);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB7CTRL);
+ set_gcsr_sw_flag(LOONGARCH_CSR_IB7ASID);
+
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCTRL0);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCNTR0);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCTRL1);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCNTR1);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCTRL2);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCNTR2);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCTRL3);
+ set_gcsr_sw_flag(LOONGARCH_CSR_PERFCNTR3);
+}
+
+static void kvm_update_vpid(struct kvm_vcpu *vcpu, int cpu)
+{
+ struct kvm_context *context;
+ unsigned long vpid;
+
+ context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
+ vpid = context->vpid_cache + 1;
+ if (!(vpid & vpid_mask)) {
+ /* finish round of 64 bit loop */
+ if (unlikely(!vpid))
+ vpid = vpid_mask + 1;
+
+ /* vpid 0 reserved for root */
+ ++vpid;
+
+ /* start new vpid cycle */
+ kvm_flush_tlb_all();
+ }
+
+ context->vpid_cache = vpid;
+ vcpu->arch.vpid = vpid;
+}
+
+void kvm_check_vpid(struct kvm_vcpu *vcpu)
+{
+ struct kvm_context *context;
+ bool migrated;
+ unsigned long ver, old, vpid;
+ int cpu;
+
+ cpu = smp_processor_id();
+ /*
+ * Are we entering guest context on a different CPU to last time?
+ * If so, the vCPU's guest TLB state on this CPU may be stale.
+ */
+ context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
+ migrated = (vcpu->cpu != cpu);
+
+ /*
+ * Check if our vpid is of an older version
+ *
+ * We also discard the stored vpid if we've executed on
+ * another CPU, as the guest mappings may have changed without
+ * hypervisor knowledge.
+ */
+ ver = vcpu->arch.vpid & ~vpid_mask;
+ old = context->vpid_cache & ~vpid_mask;
+ if (migrated || (ver != old)) {
+ kvm_update_vpid(vcpu, cpu);
+ trace_kvm_vpid_change(vcpu, vcpu->arch.vpid);
+ vcpu->cpu = cpu;
+ }
+
+ /* Restore GSTAT(0x50).vpid */
+ vpid = (vcpu->arch.vpid & vpid_mask) << CSR_GSTAT_GID_SHIFT;
+ change_csr_gstat(vpid_mask << CSR_GSTAT_GID_SHIFT, vpid);
+}
+
+static int kvm_loongarch_env_init(void)
+{
+ struct kvm_context *context;
+ int cpu, order;
+ void *addr;
+
+ vmcs = alloc_percpu(struct kvm_context);
+ if (!vmcs) {
+ pr_err("kvm: failed to allocate percpu kvm_context\n");
+ return -ENOMEM;
+ }
+
+ kvm_loongarch_ops = kzalloc(sizeof(*kvm_loongarch_ops), GFP_KERNEL);
+ if (!kvm_loongarch_ops) {
+ free_percpu(vmcs);
+ vmcs = NULL;
+ return -ENOMEM;
+ }
+ /*
+ * There will be problem in world switch code if there
+ * is page fault reenter, since pgd register is shared
+ * between root kernel and kvm hypervisor. World switch
+ * entry need be unmapped area, cannot be tlb mapped area.
+ * In future if hw pagetable walking is supported, or there
+ * is separate pgd registers between root kernel and kvm
+ * hypervisor, copying about world switch code will not be used.
+ */
+
+ order = get_order(kvm_vector_size + kvm_enter_guest_size);
+ addr = (void *)__get_free_pages(GFP_KERNEL, order);
+ if (!addr) {
+ free_percpu(vmcs);
+ vmcs = NULL;
+ kfree(kvm_loongarch_ops);
+ kvm_loongarch_ops = NULL;
+ return -ENOMEM;
+ }
+
+ memcpy(addr, kvm_vector_entry, kvm_vector_size);
+ memcpy(addr + kvm_vector_size, kvm_enter_guest, kvm_enter_guest_size);
+ flush_icache_range((unsigned long)addr, (unsigned long)addr +
+ kvm_vector_size + kvm_enter_guest_size);
+ kvm_loongarch_ops->guest_eentry = addr;
+ kvm_loongarch_ops->enter_guest = addr + kvm_vector_size;
+ kvm_loongarch_ops->page_order = order;
+
+ vpid_mask = read_csr_gstat();
+ vpid_mask = (vpid_mask & CSR_GSTAT_GIDBIT) >> CSR_GSTAT_GIDBIT_SHIFT;
+ if (vpid_mask)
+ vpid_mask = GENMASK(vpid_mask - 1, 0);
+
+ for_each_possible_cpu(cpu) {
+ context = per_cpu_ptr(vmcs, cpu);
+ context->vpid_cache = vpid_mask + 1;
+ context->last_vcpu = NULL;
+ }
+
+ kvm_init_fault();
+ kvm_init_gcsr_flag();
+
+ return 0;
+}
+
+static void kvm_loongarch_env_exit(void)
+{
+ unsigned long addr;
+
+ if (vmcs)
+ free_percpu(vmcs);
+
+ if (kvm_loongarch_ops) {
+ if (kvm_loongarch_ops->guest_eentry) {
+ addr = (unsigned long)kvm_loongarch_ops->guest_eentry;
+ free_pages(addr, kvm_loongarch_ops->page_order);
+ }
+ kfree(kvm_loongarch_ops);
+ }
+}
+
+static int kvm_loongarch_init(void)
+{
+ int r;
+
+ if (!cpu_has_lvz) {
+ kvm_info("hardware virtualization not available\n");
+ return -ENODEV;
+ }
+ r = kvm_loongarch_env_init();
+ if (r)
+ return r;
+
+ return kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+}
+
+static void kvm_loongarch_exit(void)
+{
+ kvm_exit();
+ kvm_loongarch_env_exit();
+}
+
+module_init(kvm_loongarch_init);
+module_exit(kvm_loongarch_exit);
+
+#ifdef MODULE
+static const struct cpu_feature loongarch_kvm_feature[] = {
+ { .feature = cpu_feature(LOONGARCH_LVZ) },
+ {},
+};
+MODULE_DEVICE_TABLE(cpu, loongarch_kvm_feature);
+#endif
--
2.39.1
