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Diffstat (limited to 'arch/loongarch/kvm/exit.c')
| -rw-r--r-- | arch/loongarch/kvm/exit.c | 965 |
1 files changed, 965 insertions, 0 deletions
diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c new file mode 100644 index 000000000000..cb493980d874 --- /dev/null +++ b/arch/loongarch/kvm/exit.c @@ -0,0 +1,965 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited + */ + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/kvm_host.h> +#include <linux/module.h> +#include <linux/preempt.h> +#include <linux/vmalloc.h> +#include <trace/events/kvm.h> +#include <asm/fpu.h> +#include <asm/inst.h> +#include <asm/loongarch.h> +#include <asm/mmzone.h> +#include <asm/numa.h> +#include <asm/time.h> +#include <asm/tlb.h> +#include <asm/kvm_csr.h> +#include <asm/kvm_vcpu.h> +#include "trace.h" + +static int kvm_emu_cpucfg(struct kvm_vcpu *vcpu, larch_inst inst) +{ + int rd, rj; + unsigned int index, ret; + + if (inst.reg2_format.opcode != cpucfg_op) + return EMULATE_FAIL; + + rd = inst.reg2_format.rd; + rj = inst.reg2_format.rj; + ++vcpu->stat.cpucfg_exits; + index = vcpu->arch.gprs[rj]; + + /* + * By LoongArch Reference Manual 2.2.10.5 + * Return value is 0 for undefined CPUCFG index + * + * Disable preemption since hw gcsr is accessed + */ + preempt_disable(); + switch (index) { + case 0 ... (KVM_MAX_CPUCFG_REGS - 1): + vcpu->arch.gprs[rd] = vcpu->arch.cpucfg[index]; + break; + case CPUCFG_KVM_SIG: + /* CPUCFG emulation between 0x40000000 -- 0x400000ff */ + vcpu->arch.gprs[rd] = *(unsigned int *)KVM_SIGNATURE; + break; + case CPUCFG_KVM_FEATURE: + ret = vcpu->kvm->arch.pv_features & LOONGARCH_PV_FEAT_MASK; + vcpu->arch.gprs[rd] = ret; + break; + default: + vcpu->arch.gprs[rd] = 0; + break; + } + preempt_enable(); + + return EMULATE_DONE; +} + +static unsigned long kvm_emu_read_csr(struct kvm_vcpu *vcpu, int csrid) +{ + unsigned long val = 0; + struct loongarch_csrs *csr = vcpu->arch.csr; + + /* + * From LoongArch Reference Manual Volume 1 Chapter 4.2.1 + * For undefined CSR id, return value is 0 + */ + if (get_gcsr_flag(csrid) & SW_GCSR) + val = kvm_read_sw_gcsr(csr, csrid); + else + pr_warn_once("Unsupported csrrd 0x%x with pc %lx\n", csrid, vcpu->arch.pc); + + return val; +} + +static unsigned long kvm_emu_write_csr(struct kvm_vcpu *vcpu, int csrid, unsigned long val) +{ + unsigned long old = 0; + struct loongarch_csrs *csr = vcpu->arch.csr; + + if (get_gcsr_flag(csrid) & SW_GCSR) { + old = kvm_read_sw_gcsr(csr, csrid); + kvm_write_sw_gcsr(csr, csrid, val); + } else + pr_warn_once("Unsupported csrwr 0x%x with pc %lx\n", csrid, vcpu->arch.pc); + + return old; +} + +static unsigned long kvm_emu_xchg_csr(struct kvm_vcpu *vcpu, int csrid, + unsigned long csr_mask, unsigned long val) +{ + unsigned long old = 0; + struct loongarch_csrs *csr = vcpu->arch.csr; + + if (get_gcsr_flag(csrid) & SW_GCSR) { + old = kvm_read_sw_gcsr(csr, csrid); + val = (old & ~csr_mask) | (val & csr_mask); + kvm_write_sw_gcsr(csr, csrid, val); + old = old & csr_mask; + } else + pr_warn_once("Unsupported csrxchg 0x%x with pc %lx\n", csrid, vcpu->arch.pc); + + return old; +} + +static int kvm_handle_csr(struct kvm_vcpu *vcpu, larch_inst inst) +{ + unsigned int rd, rj, csrid; + unsigned long csr_mask, val = 0; + + /* + * CSR value mask imm + * rj = 0 means csrrd + * rj = 1 means csrwr + * rj != 0,1 means csrxchg + */ + rd = inst.reg2csr_format.rd; + rj = inst.reg2csr_format.rj; + csrid = inst.reg2csr_format.csr; + + if (csrid >= LOONGARCH_CSR_PERFCTRL0 && csrid <= vcpu->arch.max_pmu_csrid) { + if (kvm_guest_has_pmu(&vcpu->arch)) { + vcpu->arch.pc -= 4; + kvm_make_request(KVM_REQ_PMU, vcpu); + return EMULATE_DONE; + } + } + + /* Process CSR ops */ + switch (rj) { + case 0: /* process csrrd */ + val = kvm_emu_read_csr(vcpu, csrid); + vcpu->arch.gprs[rd] = val; + break; + case 1: /* process csrwr */ + val = vcpu->arch.gprs[rd]; + val = kvm_emu_write_csr(vcpu, csrid, val); + vcpu->arch.gprs[rd] = val; + break; + default: /* process csrxchg */ + val = vcpu->arch.gprs[rd]; + csr_mask = vcpu->arch.gprs[rj]; + val = kvm_emu_xchg_csr(vcpu, csrid, csr_mask, val); + vcpu->arch.gprs[rd] = val; + } + + return EMULATE_DONE; +} + +int kvm_emu_iocsr(larch_inst inst, struct kvm_run *run, struct kvm_vcpu *vcpu) +{ + int idx, ret; + unsigned long *val; + u32 addr, rd, rj, opcode; + + /* + * Each IOCSR with different opcode + */ + rd = inst.reg2_format.rd; + rj = inst.reg2_format.rj; + opcode = inst.reg2_format.opcode; + addr = vcpu->arch.gprs[rj]; + run->iocsr_io.phys_addr = addr; + run->iocsr_io.is_write = 0; + val = &vcpu->arch.gprs[rd]; + + /* LoongArch is Little endian */ + switch (opcode) { + case iocsrrdb_op: + run->iocsr_io.len = 1; + break; + case iocsrrdh_op: + run->iocsr_io.len = 2; + break; + case iocsrrdw_op: + run->iocsr_io.len = 4; + break; + case iocsrrdd_op: + run->iocsr_io.len = 8; + break; + case iocsrwrb_op: + run->iocsr_io.len = 1; + run->iocsr_io.is_write = 1; + break; + case iocsrwrh_op: + run->iocsr_io.len = 2; + run->iocsr_io.is_write = 1; + break; + case iocsrwrw_op: + run->iocsr_io.len = 4; + run->iocsr_io.is_write = 1; + break; + case iocsrwrd_op: + run->iocsr_io.len = 8; + run->iocsr_io.is_write = 1; + break; + default: + return EMULATE_FAIL; + } + + if (run->iocsr_io.is_write) { + idx = srcu_read_lock(&vcpu->kvm->srcu); + ret = kvm_io_bus_write(vcpu, KVM_IOCSR_BUS, addr, run->iocsr_io.len, val); + srcu_read_unlock(&vcpu->kvm->srcu, idx); + if (ret == 0) + ret = EMULATE_DONE; + else { + ret = EMULATE_DO_IOCSR; + /* Save data and let user space to write it */ + memcpy(run->iocsr_io.data, val, run->iocsr_io.len); + } + trace_kvm_iocsr(KVM_TRACE_IOCSR_WRITE, run->iocsr_io.len, addr, val); + } else { + vcpu->arch.io_gpr = rd; /* Set register id for iocsr read completion */ + idx = srcu_read_lock(&vcpu->kvm->srcu); + ret = kvm_io_bus_read(vcpu, KVM_IOCSR_BUS, addr, + run->iocsr_io.len, run->iocsr_io.data); + srcu_read_unlock(&vcpu->kvm->srcu, idx); + if (ret == 0) { + kvm_complete_iocsr_read(vcpu, run); + ret = EMULATE_DONE; + } else + ret = EMULATE_DO_IOCSR; + trace_kvm_iocsr(KVM_TRACE_IOCSR_READ, run->iocsr_io.len, addr, NULL); + } + + return ret; +} + +int kvm_complete_iocsr_read(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + enum emulation_result er = EMULATE_DONE; + unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr]; + + switch (run->iocsr_io.len) { + case 1: + *gpr = *(s8 *)run->iocsr_io.data; + break; + case 2: + *gpr = *(s16 *)run->iocsr_io.data; + break; + case 4: + *gpr = *(s32 *)run->iocsr_io.data; + break; + case 8: + *gpr = *(s64 *)run->iocsr_io.data; + break; + default: + kvm_err("Bad IOCSR length: %d, addr is 0x%lx\n", + run->iocsr_io.len, vcpu->arch.badv); + er = EMULATE_FAIL; + break; + } + + return er; +} + +int kvm_emu_idle(struct kvm_vcpu *vcpu) +{ + ++vcpu->stat.idle_exits; + trace_kvm_exit_idle(vcpu, KVM_TRACE_EXIT_IDLE); + + if (!kvm_arch_vcpu_runnable(vcpu)) + kvm_vcpu_halt(vcpu); + + return EMULATE_DONE; +} + +static int kvm_trap_handle_gspr(struct kvm_vcpu *vcpu) +{ + unsigned long curr_pc; + larch_inst inst; + enum emulation_result er = EMULATE_DONE; + struct kvm_run *run = vcpu->run; + + /* Fetch the instruction */ + inst.word = vcpu->arch.badi; + curr_pc = vcpu->arch.pc; + update_pc(&vcpu->arch); + + trace_kvm_exit_gspr(vcpu, inst.word); + er = EMULATE_FAIL; + switch (((inst.word >> 24) & 0xff)) { + case 0x0: /* CPUCFG GSPR */ + trace_kvm_exit_cpucfg(vcpu, KVM_TRACE_EXIT_CPUCFG); + er = kvm_emu_cpucfg(vcpu, inst); + break; + case 0x4: /* CSR{RD,WR,XCHG} GSPR */ + trace_kvm_exit_csr(vcpu, KVM_TRACE_EXIT_CSR); + er = kvm_handle_csr(vcpu, inst); + break; + case 0x6: /* Cache, Idle and IOCSR GSPR */ + switch (((inst.word >> 22) & 0x3ff)) { + case 0x18: /* Cache GSPR */ + er = EMULATE_DONE; + trace_kvm_exit_cache(vcpu, KVM_TRACE_EXIT_CACHE); + break; + case 0x19: /* Idle/IOCSR GSPR */ + switch (((inst.word >> 15) & 0x1ffff)) { + case 0xc90: /* IOCSR GSPR */ + er = kvm_emu_iocsr(inst, run, vcpu); + break; + case 0xc91: /* Idle GSPR */ + er = kvm_emu_idle(vcpu); + break; + default: + er = EMULATE_FAIL; + break; + } + break; + default: + er = EMULATE_FAIL; + break; + } + break; + default: + er = EMULATE_FAIL; + break; + } + + /* Rollback PC only if emulation was unsuccessful */ + if (er == EMULATE_FAIL) { + kvm_err("[%#lx]%s: unsupported gspr instruction 0x%08x\n", + curr_pc, __func__, inst.word); + + kvm_arch_vcpu_dump_regs(vcpu); + vcpu->arch.pc = curr_pc; + } + + return er; +} + +/* + * Trigger GSPR: + * 1) Execute CPUCFG instruction; + * 2) Execute CACOP/IDLE instructions; + * 3) Access to unimplemented CSRs/IOCSRs. + */ +static int kvm_handle_gspr(struct kvm_vcpu *vcpu, int ecode) +{ + int ret = RESUME_GUEST; + enum emulation_result er = EMULATE_DONE; + + er = kvm_trap_handle_gspr(vcpu); + + if (er == EMULATE_DONE) { + ret = RESUME_GUEST; + } else if (er == EMULATE_DO_MMIO) { + vcpu->run->exit_reason = KVM_EXIT_MMIO; + ret = RESUME_HOST; + } else if (er == EMULATE_DO_IOCSR) { + vcpu->run->exit_reason = KVM_EXIT_LOONGARCH_IOCSR; + ret = RESUME_HOST; + } else { + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + ret = RESUME_GUEST; + } + + return ret; +} + +int kvm_emu_mmio_read(struct kvm_vcpu *vcpu, larch_inst inst) +{ + int idx, ret; + unsigned int op8, opcode, rd; + struct kvm_run *run = vcpu->run; + + run->mmio.phys_addr = vcpu->arch.badv; + vcpu->mmio_needed = 2; /* signed */ + op8 = (inst.word >> 24) & 0xff; + ret = EMULATE_DO_MMIO; + + switch (op8) { + case 0x24 ... 0x27: /* ldptr.w/d process */ + rd = inst.reg2i14_format.rd; + opcode = inst.reg2i14_format.opcode; + + switch (opcode) { + case ldptrw_op: + run->mmio.len = 4; + break; + case ldptrd_op: + run->mmio.len = 8; + break; + default: + break; + } + break; + case 0x28 ... 0x2e: /* ld.b/h/w/d, ld.bu/hu/wu process */ + rd = inst.reg2i12_format.rd; + opcode = inst.reg2i12_format.opcode; + + switch (opcode) { + case ldb_op: + run->mmio.len = 1; + break; + case ldbu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 1; + break; + case ldh_op: + run->mmio.len = 2; + break; + case ldhu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 2; + break; + case ldw_op: + run->mmio.len = 4; + break; + case ldwu_op: + vcpu->mmio_needed = 1; /* unsigned */ + run->mmio.len = 4; + break; + case ldd_op: + run->mmio.len = 8; + break; + default: + ret = EMULATE_FAIL; + break; + } + break; + case 0x38: /* ldx.b/h/w/d, ldx.bu/hu/wu process */ + rd = inst.reg3_format.rd; + opcode = inst.reg3_format.opcode; + + switch (opcode) { + case ldxb_op: + run->mmio.len = 1; + break; + case ldxbu_op: + run->mmio.len = 1; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxh_op: + run->mmio.len = 2; + break; + case ldxhu_op: + run->mmio.len = 2; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxw_op: + run->mmio.len = 4; + break; + case ldxwu_op: + run->mmio.len = 4; + vcpu->mmio_needed = 1; /* unsigned */ + break; + case ldxd_op: + run->mmio.len = 8; + break; + default: + ret = EMULATE_FAIL; + break; + } + break; + default: + ret = EMULATE_FAIL; + } + + if (ret == EMULATE_DO_MMIO) { + trace_kvm_mmio(KVM_TRACE_MMIO_READ, run->mmio.len, run->mmio.phys_addr, NULL); + + vcpu->arch.io_gpr = rd; /* Set for kvm_complete_mmio_read() use */ + + /* + * If mmio device such as PCH-PIC is emulated in KVM, + * it need not return to user space to handle the mmio + * exception. + */ + idx = srcu_read_lock(&vcpu->kvm->srcu); + ret = kvm_io_bus_read(vcpu, KVM_MMIO_BUS, vcpu->arch.badv, + run->mmio.len, run->mmio.data); + srcu_read_unlock(&vcpu->kvm->srcu, idx); + if (!ret) { + kvm_complete_mmio_read(vcpu, run); + update_pc(&vcpu->arch); + vcpu->mmio_needed = 0; + return EMULATE_DONE; + } + + run->mmio.is_write = 0; + vcpu->mmio_is_write = 0; + return EMULATE_DO_MMIO; + } + + kvm_err("Read not supported Inst=0x%08x @%lx BadVaddr:%#lx\n", + inst.word, vcpu->arch.pc, vcpu->arch.badv); + kvm_arch_vcpu_dump_regs(vcpu); + vcpu->mmio_needed = 0; + + return ret; +} + +int kvm_complete_mmio_read(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + enum emulation_result er = EMULATE_DONE; + unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr]; + + /* Update with new PC */ + update_pc(&vcpu->arch); + switch (run->mmio.len) { + case 1: + if (vcpu->mmio_needed == 2) + *gpr = *(s8 *)run->mmio.data; + else + *gpr = *(u8 *)run->mmio.data; + break; + case 2: + if (vcpu->mmio_needed == 2) + *gpr = *(s16 *)run->mmio.data; + else + *gpr = *(u16 *)run->mmio.data; + break; + case 4: + if (vcpu->mmio_needed == 2) + *gpr = *(s32 *)run->mmio.data; + else + *gpr = *(u32 *)run->mmio.data; + break; + case 8: + *gpr = *(s64 *)run->mmio.data; + break; + default: + kvm_err("Bad MMIO length: %d, addr is 0x%lx\n", + run->mmio.len, vcpu->arch.badv); + er = EMULATE_FAIL; + break; + } + + trace_kvm_mmio(KVM_TRACE_MMIO_READ, run->mmio.len, + run->mmio.phys_addr, run->mmio.data); + + return er; +} + +int kvm_emu_mmio_write(struct kvm_vcpu *vcpu, larch_inst inst) +{ + int idx, ret; + unsigned int rd, op8, opcode; + unsigned long curr_pc, rd_val = 0; + struct kvm_run *run = vcpu->run; + void *data = run->mmio.data; + + /* + * Update PC and hold onto current PC in case there is + * an error and we want to rollback the PC + */ + curr_pc = vcpu->arch.pc; + update_pc(&vcpu->arch); + + op8 = (inst.word >> 24) & 0xff; + run->mmio.phys_addr = vcpu->arch.badv; + ret = EMULATE_DO_MMIO; + switch (op8) { + case 0x24 ... 0x27: /* stptr.w/d process */ + rd = inst.reg2i14_format.rd; + opcode = inst.reg2i14_format.opcode; + + switch (opcode) { + case stptrw_op: + run->mmio.len = 4; + *(unsigned int *)data = vcpu->arch.gprs[rd]; + break; + case stptrd_op: + run->mmio.len = 8; + *(unsigned long *)data = vcpu->arch.gprs[rd]; + break; + default: + ret = EMULATE_FAIL; + break; + } + break; + case 0x28 ... 0x2e: /* st.b/h/w/d process */ + rd = inst.reg2i12_format.rd; + opcode = inst.reg2i12_format.opcode; + rd_val = vcpu->arch.gprs[rd]; + + switch (opcode) { + case stb_op: + run->mmio.len = 1; + *(unsigned char *)data = rd_val; + break; + case sth_op: + run->mmio.len = 2; + *(unsigned short *)data = rd_val; + break; + case stw_op: + run->mmio.len = 4; + *(unsigned int *)data = rd_val; + break; + case std_op: + run->mmio.len = 8; + *(unsigned long *)data = rd_val; + break; + default: + ret = EMULATE_FAIL; + break; + } + break; + case 0x38: /* stx.b/h/w/d process */ + rd = inst.reg3_format.rd; + opcode = inst.reg3_format.opcode; + + switch (opcode) { + case stxb_op: + run->mmio.len = 1; + *(unsigned char *)data = vcpu->arch.gprs[rd]; + break; + case stxh_op: + run->mmio.len = 2; + *(unsigned short *)data = vcpu->arch.gprs[rd]; + break; + case stxw_op: + run->mmio.len = 4; + *(unsigned int *)data = vcpu->arch.gprs[rd]; + break; + case stxd_op: + run->mmio.len = 8; + *(unsigned long *)data = vcpu->arch.gprs[rd]; + break; + default: + ret = EMULATE_FAIL; + break; + } + break; + default: + ret = EMULATE_FAIL; + } + + if (ret == EMULATE_DO_MMIO) { + trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, run->mmio.len, run->mmio.phys_addr, data); + + /* + * If mmio device such as PCH-PIC is emulated in KVM, + * it need not return to user space to handle the mmio + * exception. + */ + idx = srcu_read_lock(&vcpu->kvm->srcu); + ret = kvm_io_bus_write(vcpu, KVM_MMIO_BUS, vcpu->arch.badv, run->mmio.len, data); + srcu_read_unlock(&vcpu->kvm->srcu, idx); + if (!ret) + return EMULATE_DONE; + + run->mmio.is_write = 1; + vcpu->mmio_needed = 1; + vcpu->mmio_is_write = 1; + return EMULATE_DO_MMIO; + } + + vcpu->arch.pc = curr_pc; + kvm_err("Write not supported Inst=0x%08x @%lx BadVaddr:%#lx\n", + inst.word, vcpu->arch.pc, vcpu->arch.badv); + kvm_arch_vcpu_dump_regs(vcpu); + /* Rollback PC if emulation was unsuccessful */ + + return ret; +} + +static int kvm_handle_rdwr_fault(struct kvm_vcpu *vcpu, bool write, int ecode) +{ + int ret; + larch_inst inst; + enum emulation_result er = EMULATE_DONE; + struct kvm_run *run = vcpu->run; + unsigned long badv = vcpu->arch.badv; + + /* Inject ADE exception if exceed max GPA size */ + if (unlikely(badv >= vcpu->kvm->arch.gpa_size)) { + kvm_queue_exception(vcpu, EXCCODE_ADE, EXSUBCODE_ADEM); + return RESUME_GUEST; + } + + ret = kvm_handle_mm_fault(vcpu, badv, write, ecode); + if (ret) { + /* Treat as MMIO */ + inst.word = vcpu->arch.badi; + if (write) { + er = kvm_emu_mmio_write(vcpu, inst); + } else { + /* A code fetch fault doesn't count as an MMIO */ + if (kvm_is_ifetch_fault(&vcpu->arch)) { + kvm_queue_exception(vcpu, EXCCODE_ADE, EXSUBCODE_ADEF); + return RESUME_GUEST; + } + + er = kvm_emu_mmio_read(vcpu, inst); + } + } + + if (er == EMULATE_DONE) { + ret = RESUME_GUEST; + } else if (er == EMULATE_DO_MMIO) { + run->exit_reason = KVM_EXIT_MMIO; + ret = RESUME_HOST; + } else { + kvm_queue_exception(vcpu, EXCCODE_ADE, EXSUBCODE_ADEM); + ret = RESUME_GUEST; + } + + return ret; +} + +static int kvm_handle_read_fault(struct kvm_vcpu *vcpu, int ecode) +{ + return kvm_handle_rdwr_fault(vcpu, false, ecode); +} + +static int kvm_handle_write_fault(struct kvm_vcpu *vcpu, int ecode) +{ + return kvm_handle_rdwr_fault(vcpu, true, ecode); +} + +int kvm_complete_user_service(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + update_pc(&vcpu->arch); + kvm_write_reg(vcpu, LOONGARCH_GPR_A0, run->hypercall.ret); + + return 0; +} + +/** + * kvm_handle_fpu_disabled() - Guest used fpu however it is disabled at host + * @vcpu: Virtual CPU context. + * @ecode: Exception code. + * + * Handle when the guest attempts to use fpu which hasn't been allowed + * by the root context. + */ +static int kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu, int ecode) +{ + struct kvm_run *run = vcpu->run; + + if (!kvm_guest_has_fpu(&vcpu->arch)) { + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + return RESUME_GUEST; + } + + /* + * If guest FPU not present, the FPU operation should have been + * treated as a reserved instruction! + * If FPU already in use, we shouldn't get this at all. + */ + if (WARN_ON(vcpu->arch.aux_inuse & KVM_LARCH_FPU)) { + kvm_err("%s internal error\n", __func__); + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + return RESUME_HOST; + } + + kvm_own_fpu(vcpu); + + return RESUME_GUEST; +} + +static long kvm_save_notify(struct kvm_vcpu *vcpu) +{ + unsigned long id, data; + + id = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); + data = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); + switch (id) { + case BIT(KVM_FEATURE_STEAL_TIME): + if (data & ~(KVM_STEAL_PHYS_MASK | KVM_STEAL_PHYS_VALID)) + return KVM_HCALL_INVALID_PARAMETER; + + vcpu->arch.st.guest_addr = data; + if (!(data & KVM_STEAL_PHYS_VALID)) + return 0; + + vcpu->arch.st.last_steal = current->sched_info.run_delay; + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); + return 0; + default: + return KVM_HCALL_INVALID_CODE; + } +} + +/* + * kvm_handle_lsx_disabled() - Guest used LSX while disabled in root. + * @vcpu: Virtual CPU context. + * @ecode: Exception code. + * + * Handle when the guest attempts to use LSX when it is disabled in the root + * context. + */ +static int kvm_handle_lsx_disabled(struct kvm_vcpu *vcpu, int ecode) +{ + if (kvm_own_lsx(vcpu)) + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + + return RESUME_GUEST; +} + +/* + * kvm_handle_lasx_disabled() - Guest used LASX while disabled in root. + * @vcpu: Virtual CPU context. + * @ecode: Exception code. + * + * Handle when the guest attempts to use LASX when it is disabled in the root + * context. + */ +static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu, int ecode) +{ + if (kvm_own_lasx(vcpu)) + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + + return RESUME_GUEST; +} + +static int kvm_handle_lbt_disabled(struct kvm_vcpu *vcpu, int ecode) +{ + if (kvm_own_lbt(vcpu)) + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + + return RESUME_GUEST; +} + +static void kvm_send_pv_ipi(struct kvm_vcpu *vcpu) +{ + unsigned int min, cpu; + struct kvm_vcpu *dest; + DECLARE_BITMAP(ipi_bitmap, BITS_PER_LONG * 2) = { + kvm_read_reg(vcpu, LOONGARCH_GPR_A1), + kvm_read_reg(vcpu, LOONGARCH_GPR_A2) + }; + + min = kvm_read_reg(vcpu, LOONGARCH_GPR_A3); + for_each_set_bit(cpu, ipi_bitmap, BITS_PER_LONG * 2) { + dest = kvm_get_vcpu_by_cpuid(vcpu->kvm, cpu + min); + if (!dest) + continue; + + /* Send SWI0 to dest vcpu to emulate IPI interrupt */ + kvm_queue_irq(dest, INT_SWI0); + kvm_vcpu_kick(dest); + } +} + +/* + * Hypercall emulation always return to guest, Caller should check retval. + */ +static void kvm_handle_service(struct kvm_vcpu *vcpu) +{ + long ret = KVM_HCALL_INVALID_CODE; + unsigned long func = kvm_read_reg(vcpu, LOONGARCH_GPR_A0); + + switch (func) { + case KVM_HCALL_FUNC_IPI: + if (kvm_guest_has_pv_feature(vcpu, KVM_FEATURE_IPI)) { + kvm_send_pv_ipi(vcpu); + ret = KVM_HCALL_SUCCESS; + } + break; + case KVM_HCALL_FUNC_NOTIFY: + if (kvm_guest_has_pv_feature(vcpu, KVM_FEATURE_STEAL_TIME)) + ret = kvm_save_notify(vcpu); + break; + default: + break; + } + + kvm_write_reg(vcpu, LOONGARCH_GPR_A0, ret); +} + +static int kvm_handle_hypercall(struct kvm_vcpu *vcpu, int ecode) +{ + int ret; + larch_inst inst; + unsigned int code; + + inst.word = vcpu->arch.badi; + code = inst.reg0i15_format.immediate; + ret = RESUME_GUEST; + + switch (code) { + case KVM_HCALL_SERVICE: + vcpu->stat.hypercall_exits++; + kvm_handle_service(vcpu); + break; + case KVM_HCALL_USER_SERVICE: + if (!kvm_guest_has_pv_feature(vcpu, KVM_FEATURE_USER_HCALL)) { + kvm_write_reg(vcpu, LOONGARCH_GPR_A0, KVM_HCALL_INVALID_CODE); + break; + } + + vcpu->stat.hypercall_exits++; + vcpu->run->exit_reason = KVM_EXIT_HYPERCALL; + vcpu->run->hypercall.nr = KVM_HCALL_USER_SERVICE; + vcpu->run->hypercall.args[0] = kvm_read_reg(vcpu, LOONGARCH_GPR_A0); + vcpu->run->hypercall.args[1] = kvm_read_reg(vcpu, LOONGARCH_GPR_A1); + vcpu->run->hypercall.args[2] = kvm_read_reg(vcpu, LOONGARCH_GPR_A2); + vcpu->run->hypercall.args[3] = kvm_read_reg(vcpu, LOONGARCH_GPR_A3); + vcpu->run->hypercall.args[4] = kvm_read_reg(vcpu, LOONGARCH_GPR_A4); + vcpu->run->hypercall.args[5] = kvm_read_reg(vcpu, LOONGARCH_GPR_A5); + vcpu->run->hypercall.flags = 0; + /* + * Set invalid return value by default, let user-mode VMM modify it. + */ + vcpu->run->hypercall.ret = KVM_HCALL_INVALID_CODE; + ret = RESUME_HOST; + break; + case KVM_HCALL_SWDBG: + /* KVM_HCALL_SWDBG only in effective when SW_BP is enabled */ + if (vcpu->guest_debug & KVM_GUESTDBG_SW_BP_MASK) { + vcpu->run->exit_reason = KVM_EXIT_DEBUG; + ret = RESUME_HOST; + break; + } + fallthrough; + default: + /* Treat it as noop intruction, only set return value */ + kvm_write_reg(vcpu, LOONGARCH_GPR_A0, KVM_HCALL_INVALID_CODE); + break; + } + + if (ret == RESUME_GUEST) + update_pc(&vcpu->arch); + + return ret; +} + +/* + * LoongArch KVM callback handling for unimplemented guest exiting + */ +static int kvm_fault_ni(struct kvm_vcpu *vcpu, int ecode) +{ + unsigned int inst; + unsigned long badv; + + /* Fetch the instruction */ + inst = vcpu->arch.badi; + badv = vcpu->arch.badv; + kvm_err("ECode: %d PC=%#lx Inst=0x%08x BadVaddr=%#lx ESTAT=%#lx\n", + ecode, vcpu->arch.pc, inst, badv, read_gcsr_estat()); + kvm_arch_vcpu_dump_regs(vcpu); + kvm_queue_exception(vcpu, EXCCODE_INE, 0); + + return RESUME_GUEST; +} + +static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = { + [0 ... EXCCODE_INT_START - 1] = kvm_fault_ni, + [EXCCODE_TLBI] = kvm_handle_read_fault, + [EXCCODE_TLBL] = kvm_handle_read_fault, + [EXCCODE_TLBS] = kvm_handle_write_fault, + [EXCCODE_TLBM] = kvm_handle_write_fault, + [EXCCODE_FPDIS] = kvm_handle_fpu_disabled, + [EXCCODE_LSXDIS] = kvm_handle_lsx_disabled, + [EXCCODE_LASXDIS] = kvm_handle_lasx_disabled, + [EXCCODE_BTDIS] = kvm_handle_lbt_disabled, + [EXCCODE_GSPR] = kvm_handle_gspr, + [EXCCODE_HVC] = kvm_handle_hypercall, +}; + +int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault) +{ + return kvm_fault_tables[fault](vcpu, fault); +} |
