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-rw-r--r--arch/s390/kvm/sigp.c495
1 files changed, 495 insertions, 0 deletions
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
new file mode 100644
index 0000000000..d9696b5300
--- /dev/null
+++ b/arch/s390/kvm/sigp.c
@@ -0,0 +1,495 @@
+// 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)
+{
+ *status_reg &= 0xffffffff00000000UL;
+
+ /* Reject set arch order, with czam we're always in z/Arch mode. */
+ *status_reg |= SIGP_STATUS_INVALID_PARAMETER;
+ 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 occur 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);
+
+ if (order_code == SIGP_EXTERNAL_CALL) {
+ trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
+
+ 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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-29 02:15:18 +0000