| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * handling interprocessor communication |
| * |
| * Copyright IBM Corp. 2008, 2013 |
| * |
| * Author(s): Carsten Otte <cotte@de.ibm.com> |
| * Christian Borntraeger <borntraeger@de.ibm.com> |
| * Christian Ehrhardt <ehrhardt@de.ibm.com> |
| */ |
| |
| #include <linux/kvm.h> |
| #include <linux/kvm_host.h> |
| #include <linux/slab.h> |
| #include <asm/sigp.h> |
| #include "gaccess.h" |
| #include "kvm-s390.h" |
| #include "trace.h" |
| |
| static int __sigp_sense(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu, |
| u64 *reg) |
| { |
| const bool stopped = kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED); |
| int rc; |
| int ext_call_pending; |
| |
| ext_call_pending = kvm_s390_ext_call_pending(dst_vcpu); |
| if (!stopped && !ext_call_pending) |
| rc = SIGP_CC_ORDER_CODE_ACCEPTED; |
| else { |
| *reg &= 0xffffffff00000000UL; |
| if (ext_call_pending) |
| *reg |= SIGP_STATUS_EXT_CALL_PENDING; |
| if (stopped) |
| *reg |= SIGP_STATUS_STOPPED; |
| rc = SIGP_CC_STATUS_STORED; |
| } |
| |
| VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", dst_vcpu->vcpu_id, |
| rc); |
| return rc; |
| } |
| |
| static int __inject_sigp_emergency(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu) |
| { |
| struct kvm_s390_irq irq = { |
| .type = KVM_S390_INT_EMERGENCY, |
| .u.emerg.code = vcpu->vcpu_id, |
| }; |
| int rc = 0; |
| |
| rc = kvm_s390_inject_vcpu(dst_vcpu, &irq); |
| if (!rc) |
| VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", |
| dst_vcpu->vcpu_id); |
| |
| return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED; |
| } |
| |
| static int __sigp_emergency(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu) |
| { |
| return __inject_sigp_emergency(vcpu, dst_vcpu); |
| } |
| |
| static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, |
| u16 asn, u64 *reg) |
| { |
| const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT; |
| u16 p_asn, s_asn; |
| psw_t *psw; |
| bool idle; |
| |
| idle = is_vcpu_idle(vcpu); |
| psw = &dst_vcpu->arch.sie_block->gpsw; |
| p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */ |
| s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */ |
| |
| /* Inject the emergency signal? */ |
| if (!is_vcpu_stopped(vcpu) |
| || (psw->mask & psw_int_mask) != psw_int_mask |
| || (idle && psw->addr != 0) |
| || (!idle && (asn == p_asn || asn == s_asn))) { |
| return __inject_sigp_emergency(vcpu, dst_vcpu); |
| } else { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INCORRECT_STATE; |
| return SIGP_CC_STATUS_STORED; |
| } |
| } |
| |
| static int __sigp_external_call(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, u64 *reg) |
| { |
| struct kvm_s390_irq irq = { |
| .type = KVM_S390_INT_EXTERNAL_CALL, |
| .u.extcall.code = vcpu->vcpu_id, |
| }; |
| int rc; |
| |
| rc = kvm_s390_inject_vcpu(dst_vcpu, &irq); |
| if (rc == -EBUSY) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_EXT_CALL_PENDING; |
| return SIGP_CC_STATUS_STORED; |
| } else if (rc == 0) { |
| VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", |
| dst_vcpu->vcpu_id); |
| } |
| |
| return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED; |
| } |
| |
| static int __sigp_stop(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu) |
| { |
| struct kvm_s390_irq irq = { |
| .type = KVM_S390_SIGP_STOP, |
| }; |
| int rc; |
| |
| rc = kvm_s390_inject_vcpu(dst_vcpu, &irq); |
| if (rc == -EBUSY) |
| rc = SIGP_CC_BUSY; |
| else if (rc == 0) |
| VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", |
| dst_vcpu->vcpu_id); |
| |
| return rc; |
| } |
| |
| static int __sigp_stop_and_store_status(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, u64 *reg) |
| { |
| struct kvm_s390_irq irq = { |
| .type = KVM_S390_SIGP_STOP, |
| .u.stop.flags = KVM_S390_STOP_FLAG_STORE_STATUS, |
| }; |
| int rc; |
| |
| rc = kvm_s390_inject_vcpu(dst_vcpu, &irq); |
| if (rc == -EBUSY) |
| rc = SIGP_CC_BUSY; |
| else if (rc == 0) |
| VCPU_EVENT(vcpu, 4, "sent sigp stop and store status to cpu %x", |
| dst_vcpu->vcpu_id); |
| |
| return rc; |
| } |
| |
| static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter, |
| u64 *status_reg) |
| { |
| unsigned int i; |
| struct kvm_vcpu *v; |
| bool all_stopped = true; |
| |
| kvm_for_each_vcpu(i, v, vcpu->kvm) { |
| if (v == vcpu) |
| continue; |
| if (!is_vcpu_stopped(v)) |
| all_stopped = false; |
| } |
| |
| *status_reg &= 0xffffffff00000000UL; |
| |
| /* Reject set arch order, with czam we're always in z/Arch mode. */ |
| *status_reg |= (all_stopped ? SIGP_STATUS_INVALID_PARAMETER : |
| SIGP_STATUS_INCORRECT_STATE); |
| return SIGP_CC_STATUS_STORED; |
| } |
| |
| static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu, |
| u32 address, u64 *reg) |
| { |
| struct kvm_s390_irq irq = { |
| .type = KVM_S390_SIGP_SET_PREFIX, |
| .u.prefix.address = address & 0x7fffe000u, |
| }; |
| int rc; |
| |
| /* |
| * Make sure the new value is valid memory. We only need to check the |
| * first page, since address is 8k aligned and memory pieces are always |
| * at least 1MB aligned and have at least a size of 1MB. |
| */ |
| if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INVALID_PARAMETER; |
| return SIGP_CC_STATUS_STORED; |
| } |
| |
| rc = kvm_s390_inject_vcpu(dst_vcpu, &irq); |
| if (rc == -EBUSY) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INCORRECT_STATE; |
| return SIGP_CC_STATUS_STORED; |
| } |
| |
| return rc; |
| } |
| |
| static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, |
| u32 addr, u64 *reg) |
| { |
| int rc; |
| |
| if (!kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED)) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INCORRECT_STATE; |
| return SIGP_CC_STATUS_STORED; |
| } |
| |
| addr &= 0x7ffffe00; |
| rc = kvm_s390_store_status_unloaded(dst_vcpu, addr); |
| if (rc == -EFAULT) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INVALID_PARAMETER; |
| rc = SIGP_CC_STATUS_STORED; |
| } |
| return rc; |
| } |
| |
| static int __sigp_sense_running(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, u64 *reg) |
| { |
| int rc; |
| |
| if (!test_kvm_facility(vcpu->kvm, 9)) { |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_INVALID_ORDER; |
| return SIGP_CC_STATUS_STORED; |
| } |
| |
| if (kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_RUNNING)) { |
| /* running */ |
| rc = SIGP_CC_ORDER_CODE_ACCEPTED; |
| } else { |
| /* not running */ |
| *reg &= 0xffffffff00000000UL; |
| *reg |= SIGP_STATUS_NOT_RUNNING; |
| rc = SIGP_CC_STATUS_STORED; |
| } |
| |
| VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", |
| dst_vcpu->vcpu_id, rc); |
| |
| return rc; |
| } |
| |
| static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, u8 order_code) |
| { |
| struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int; |
| /* handle (RE)START in user space */ |
| int rc = -EOPNOTSUPP; |
| |
| /* make sure we don't race with STOP irq injection */ |
| spin_lock(&li->lock); |
| if (kvm_s390_is_stop_irq_pending(dst_vcpu)) |
| rc = SIGP_CC_BUSY; |
| spin_unlock(&li->lock); |
| |
| return rc; |
| } |
| |
| static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu, u8 order_code) |
| { |
| /* handle (INITIAL) CPU RESET in user space */ |
| return -EOPNOTSUPP; |
| } |
| |
| static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu, |
| struct kvm_vcpu *dst_vcpu) |
| { |
| /* handle unknown orders in user space */ |
| return -EOPNOTSUPP; |
| } |
| |
| static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code, |
| u16 cpu_addr, u32 parameter, u64 *status_reg) |
| { |
| int rc; |
| struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr); |
| |
| if (!dst_vcpu) |
| return SIGP_CC_NOT_OPERATIONAL; |
| |
| /* |
| * SIGP RESTART, SIGP STOP, and SIGP STOP AND STORE STATUS orders |
| * are processed asynchronously. Until the affected VCPU finishes |
| * its work and calls back into KVM to clear the (RESTART or STOP) |
| * interrupt, we need to return any new non-reset orders "busy". |
| * |
| * This is important because a single VCPU could issue: |
| * 1) SIGP STOP $DESTINATION |
| * 2) SIGP SENSE $DESTINATION |
| * |
| * If the SIGP SENSE would not be rejected as "busy", it could |
| * return an incorrect answer as to whether the VCPU is STOPPED |
| * or OPERATING. |
| */ |
| if (order_code != SIGP_INITIAL_CPU_RESET && |
| order_code != SIGP_CPU_RESET) { |
| /* |
| * Lockless check. Both SIGP STOP and SIGP (RE)START |
| * properly synchronize everything while processing |
| * their orders, while the guest cannot observe a |
| * difference when issuing other orders from two |
| * different VCPUs. |
| */ |
| if (kvm_s390_is_stop_irq_pending(dst_vcpu) || |
| kvm_s390_is_restart_irq_pending(dst_vcpu)) |
| return SIGP_CC_BUSY; |
| } |
| |
| switch (order_code) { |
| case SIGP_SENSE: |
| vcpu->stat.instruction_sigp_sense++; |
| rc = __sigp_sense(vcpu, dst_vcpu, status_reg); |
| break; |
| case SIGP_EXTERNAL_CALL: |
| vcpu->stat.instruction_sigp_external_call++; |
| rc = __sigp_external_call(vcpu, dst_vcpu, status_reg); |
| break; |
| case SIGP_EMERGENCY_SIGNAL: |
| vcpu->stat.instruction_sigp_emergency++; |
| rc = __sigp_emergency(vcpu, dst_vcpu); |
| break; |
| case SIGP_STOP: |
| vcpu->stat.instruction_sigp_stop++; |
| rc = __sigp_stop(vcpu, dst_vcpu); |
| break; |
| case SIGP_STOP_AND_STORE_STATUS: |
| vcpu->stat.instruction_sigp_stop_store_status++; |
| rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg); |
| break; |
| case SIGP_STORE_STATUS_AT_ADDRESS: |
| vcpu->stat.instruction_sigp_store_status++; |
| rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter, |
| status_reg); |
| break; |
| case SIGP_SET_PREFIX: |
| vcpu->stat.instruction_sigp_prefix++; |
| rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg); |
| break; |
| case SIGP_COND_EMERGENCY_SIGNAL: |
| vcpu->stat.instruction_sigp_cond_emergency++; |
| rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter, |
| status_reg); |
| break; |
| case SIGP_SENSE_RUNNING: |
| vcpu->stat.instruction_sigp_sense_running++; |
| rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg); |
| break; |
| case SIGP_START: |
| vcpu->stat.instruction_sigp_start++; |
| rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code); |
| break; |
| case SIGP_RESTART: |
| vcpu->stat.instruction_sigp_restart++; |
| rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code); |
| break; |
| case SIGP_INITIAL_CPU_RESET: |
| vcpu->stat.instruction_sigp_init_cpu_reset++; |
| rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code); |
| break; |
| case SIGP_CPU_RESET: |
| vcpu->stat.instruction_sigp_cpu_reset++; |
| rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code); |
| break; |
| default: |
| vcpu->stat.instruction_sigp_unknown++; |
| rc = __prepare_sigp_unknown(vcpu, dst_vcpu); |
| } |
| |
| if (rc == -EOPNOTSUPP) |
| VCPU_EVENT(vcpu, 4, |
| "sigp order %u -> cpu %x: handled in user space", |
| order_code, dst_vcpu->vcpu_id); |
| |
| return rc; |
| } |
| |
| static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code, |
| u16 cpu_addr) |
| { |
| if (!vcpu->kvm->arch.user_sigp) |
| return 0; |
| |
| switch (order_code) { |
| case SIGP_SENSE: |
| case SIGP_EXTERNAL_CALL: |
| case SIGP_EMERGENCY_SIGNAL: |
| case SIGP_COND_EMERGENCY_SIGNAL: |
| case SIGP_SENSE_RUNNING: |
| return 0; |
| /* update counters as we're directly dropping to user space */ |
| case SIGP_STOP: |
| vcpu->stat.instruction_sigp_stop++; |
| break; |
| case SIGP_STOP_AND_STORE_STATUS: |
| vcpu->stat.instruction_sigp_stop_store_status++; |
| break; |
| case SIGP_STORE_STATUS_AT_ADDRESS: |
| vcpu->stat.instruction_sigp_store_status++; |
| break; |
| case SIGP_STORE_ADDITIONAL_STATUS: |
| vcpu->stat.instruction_sigp_store_adtl_status++; |
| break; |
| case SIGP_SET_PREFIX: |
| vcpu->stat.instruction_sigp_prefix++; |
| break; |
| case SIGP_START: |
| vcpu->stat.instruction_sigp_start++; |
| break; |
| case SIGP_RESTART: |
| vcpu->stat.instruction_sigp_restart++; |
| break; |
| case SIGP_INITIAL_CPU_RESET: |
| vcpu->stat.instruction_sigp_init_cpu_reset++; |
| break; |
| case SIGP_CPU_RESET: |
| vcpu->stat.instruction_sigp_cpu_reset++; |
| break; |
| default: |
| vcpu->stat.instruction_sigp_unknown++; |
| } |
| VCPU_EVENT(vcpu, 3, "SIGP: order %u for CPU %d handled in userspace", |
| order_code, cpu_addr); |
| |
| return 1; |
| } |
| |
| int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu) |
| { |
| int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4; |
| int r3 = vcpu->arch.sie_block->ipa & 0x000f; |
| u32 parameter; |
| u16 cpu_addr = vcpu->run->s.regs.gprs[r3]; |
| u8 order_code; |
| int rc; |
| |
| /* sigp in userspace can exit */ |
| if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) |
| return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); |
| |
| order_code = kvm_s390_get_base_disp_rs(vcpu, NULL); |
| if (handle_sigp_order_in_user_space(vcpu, order_code, cpu_addr)) |
| return -EOPNOTSUPP; |
| |
| if (r1 % 2) |
| parameter = vcpu->run->s.regs.gprs[r1]; |
| else |
| parameter = vcpu->run->s.regs.gprs[r1 + 1]; |
| |
| trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter); |
| switch (order_code) { |
| case SIGP_SET_ARCHITECTURE: |
| vcpu->stat.instruction_sigp_arch++; |
| rc = __sigp_set_arch(vcpu, parameter, |
| &vcpu->run->s.regs.gprs[r1]); |
| break; |
| default: |
| rc = handle_sigp_dst(vcpu, order_code, cpu_addr, |
| parameter, |
| &vcpu->run->s.regs.gprs[r1]); |
| } |
| |
| if (rc < 0) |
| return rc; |
| |
| kvm_s390_set_psw_cc(vcpu, rc); |
| return 0; |
| } |
| |
| /* |
| * Handle SIGP partial execution interception. |
| * |
| * This interception will occur at the source cpu when a source cpu sends an |
| * external call to a target cpu and the target cpu has the WAIT bit set in |
| * its cpuflags. Interception will occurr after the interrupt indicator bits at |
| * the target cpu have been set. All error cases will lead to instruction |
| * interception, therefore nothing is to be checked or prepared. |
| */ |
| int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu) |
| { |
| int r3 = vcpu->arch.sie_block->ipa & 0x000f; |
| u16 cpu_addr = vcpu->run->s.regs.gprs[r3]; |
| struct kvm_vcpu *dest_vcpu; |
| u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL); |
| |
| trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr); |
| |
| if (order_code == SIGP_EXTERNAL_CALL) { |
| dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr); |
| BUG_ON(dest_vcpu == NULL); |
| |
| kvm_s390_vcpu_wakeup(dest_vcpu); |
| kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED); |
| return 0; |
| } |
| |
| return -EOPNOTSUPP; |
| } |