Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 492 insertions, 0 deletions

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
new file mode 100644
index 000000000..a389fa85c
--- /dev/null
+++ b/arch/s390/kvm/intercept.c
@@ -0,0 +1,492 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * in-kernel handling for sie intercepts
+ *
+ * Copyright IBM Corp. 2008, 2014
+ *
+ *    Author(s): Carsten Otte <cotte@de.ibm.com>
+ *               Christian Borntraeger <borntraeger@de.ibm.com>
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/errno.h>
+#include <linux/pagemap.h>
+
+#include <asm/kvm_host.h>
+#include <asm/asm-offsets.h>
+#include <asm/irq.h>
+#include <asm/sysinfo.h>
+
+#include "kvm-s390.h"
+#include "gaccess.h"
+#include "trace.h"
+#include "trace-s390.h"
+
+u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
+{
+	struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
+	u8 ilen = 0;
+
+	switch (vcpu->arch.sie_block->icptcode) {
+	case ICPT_INST:
+	case ICPT_INSTPROGI:
+	case ICPT_OPEREXC:
+	case ICPT_PARTEXEC:
+	case ICPT_IOINST:
+		/* instruction only stored for these icptcodes */
+		ilen = insn_length(vcpu->arch.sie_block->ipa >> 8);
+		/* Use the length of the EXECUTE instruction if necessary */
+		if (sie_block->icptstatus & 1) {
+			ilen = (sie_block->icptstatus >> 4) & 0x6;
+			if (!ilen)
+				ilen = 4;
+		}
+		break;
+	case ICPT_PROGI:
+		/* bit 1+2 of pgmilc are the ilc, so we directly get ilen */
+		ilen = vcpu->arch.sie_block->pgmilc & 0x6;
+		break;
+	}
+	return ilen;
+}
+
+static int handle_stop(struct kvm_vcpu *vcpu)
+{
+	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
+	int rc = 0;
+	uint8_t flags, stop_pending;
+
+	vcpu->stat.exit_stop_request++;
+
+	/* delay the stop if any non-stop irq is pending */
+	if (kvm_s390_vcpu_has_irq(vcpu, 1))
+		return 0;
+
+	/* avoid races with the injection/SIGP STOP code */
+	spin_lock(&li->lock);
+	flags = li->irq.stop.flags;
+	stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
+	spin_unlock(&li->lock);
+
+	trace_kvm_s390_stop_request(stop_pending, flags);
+	if (!stop_pending)
+		return 0;
+
+	if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
+		rc = kvm_s390_vcpu_store_status(vcpu,
+						KVM_S390_STORE_STATUS_NOADDR);
+		if (rc)
+			return rc;
+	}
+
+	if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
+		kvm_s390_vcpu_stop(vcpu);
+	return -EOPNOTSUPP;
+}
+
+static int handle_validity(struct kvm_vcpu *vcpu)
+{
+	int viwhy = vcpu->arch.sie_block->ipb >> 16;
+
+	vcpu->stat.exit_validity++;
+	trace_kvm_s390_intercept_validity(vcpu, viwhy);
+	KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy,
+		  current->pid, vcpu->kvm);
+
+	/* do not warn on invalid runtime instrumentation mode */
+	WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n",
+		  viwhy);
+	return -EINVAL;
+}
+
+static int handle_instruction(struct kvm_vcpu *vcpu)
+{
+	vcpu->stat.exit_instruction++;
+	trace_kvm_s390_intercept_instruction(vcpu,
+					     vcpu->arch.sie_block->ipa,
+					     vcpu->arch.sie_block->ipb);
+
+	switch (vcpu->arch.sie_block->ipa >> 8) {
+	case 0x01:
+		return kvm_s390_handle_01(vcpu);
+	case 0x82:
+		return kvm_s390_handle_lpsw(vcpu);
+	case 0x83:
+		return kvm_s390_handle_diag(vcpu);
+	case 0xaa:
+		return kvm_s390_handle_aa(vcpu);
+	case 0xae:
+		return kvm_s390_handle_sigp(vcpu);
+	case 0xb2:
+		return kvm_s390_handle_b2(vcpu);
+	case 0xb6:
+		return kvm_s390_handle_stctl(vcpu);
+	case 0xb7:
+		return kvm_s390_handle_lctl(vcpu);
+	case 0xb9:
+		return kvm_s390_handle_b9(vcpu);
+	case 0xe3:
+		return kvm_s390_handle_e3(vcpu);
+	case 0xe5:
+		return kvm_s390_handle_e5(vcpu);
+	case 0xeb:
+		return kvm_s390_handle_eb(vcpu);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)
+{
+	struct kvm_s390_pgm_info pgm_info = {
+		.code = vcpu->arch.sie_block->iprcc,
+		/* the PSW has already been rewound */
+		.flags = KVM_S390_PGM_FLAGS_NO_REWIND,
+	};
+
+	switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
+	case PGM_AFX_TRANSLATION:
+	case PGM_ASX_TRANSLATION:
+	case PGM_EX_TRANSLATION:
+	case PGM_LFX_TRANSLATION:
+	case PGM_LSTE_SEQUENCE:
+	case PGM_LSX_TRANSLATION:
+	case PGM_LX_TRANSLATION:
+	case PGM_PRIMARY_AUTHORITY:
+	case PGM_SECONDARY_AUTHORITY:
+	case PGM_SPACE_SWITCH:
+		pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
+		break;
+	case PGM_ALEN_TRANSLATION:
+	case PGM_ALE_SEQUENCE:
+	case PGM_ASTE_INSTANCE:
+	case PGM_ASTE_SEQUENCE:
+	case PGM_ASTE_VALIDITY:
+	case PGM_EXTENDED_AUTHORITY:
+		pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
+		break;
+	case PGM_ASCE_TYPE:
+	case PGM_PAGE_TRANSLATION:
+	case PGM_REGION_FIRST_TRANS:
+	case PGM_REGION_SECOND_TRANS:
+	case PGM_REGION_THIRD_TRANS:
+	case PGM_SEGMENT_TRANSLATION:
+		pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
+		pgm_info.exc_access_id  = vcpu->arch.sie_block->eai;
+		pgm_info.op_access_id  = vcpu->arch.sie_block->oai;
+		break;
+	case PGM_MONITOR:
+		pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn;
+		pgm_info.mon_code = vcpu->arch.sie_block->tecmc;
+		break;
+	case PGM_VECTOR_PROCESSING:
+	case PGM_DATA:
+		pgm_info.data_exc_code = vcpu->arch.sie_block->dxc;
+		break;
+	case PGM_PROTECTION:
+		pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
+		pgm_info.exc_access_id  = vcpu->arch.sie_block->eai;
+		break;
+	default:
+		break;
+	}
+
+	if (vcpu->arch.sie_block->iprcc & PGM_PER) {
+		pgm_info.per_code = vcpu->arch.sie_block->perc;
+		pgm_info.per_atmid = vcpu->arch.sie_block->peratmid;
+		pgm_info.per_address = vcpu->arch.sie_block->peraddr;
+		pgm_info.per_access_id = vcpu->arch.sie_block->peraid;
+	}
+	return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
+}
+
+/*
+ * restore ITDB to program-interruption TDB in guest lowcore
+ * and set TX abort indication if required
+*/
+static int handle_itdb(struct kvm_vcpu *vcpu)
+{
+	struct kvm_s390_itdb *itdb;
+	int rc;
+
+	if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
+		return 0;
+	if (current->thread.per_flags & PER_FLAG_NO_TE)
+		return 0;
+	itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba;
+	rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
+	if (rc)
+		return rc;
+	memset(itdb, 0, sizeof(*itdb));
+
+	return 0;
+}
+
+#define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
+
+static int handle_prog(struct kvm_vcpu *vcpu)
+{
+	psw_t psw;
+	int rc;
+
+	vcpu->stat.exit_program_interruption++;
+
+	if (guestdbg_enabled(vcpu) && per_event(vcpu)) {
+		rc = kvm_s390_handle_per_event(vcpu);
+		if (rc)
+			return rc;
+		/* the interrupt might have been filtered out completely */
+		if (vcpu->arch.sie_block->iprcc == 0)
+			return 0;
+	}
+
+	trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
+	if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
+		rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
+		if (rc)
+			return rc;
+		/* Avoid endless loops of specification exceptions */
+		if (!is_valid_psw(&psw))
+			return -EOPNOTSUPP;
+	}
+	rc = handle_itdb(vcpu);
+	if (rc)
+		return rc;
+
+	return inject_prog_on_prog_intercept(vcpu);
+}
+
+/**
+ * handle_external_interrupt - used for external interruption interceptions
+ *
+ * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if
+ * the new PSW does not have external interrupts disabled. In the first case,
+ * we've got to deliver the interrupt manually, and in the second case, we
+ * drop to userspace to handle the situation there.
+ */
+static int handle_external_interrupt(struct kvm_vcpu *vcpu)
+{
+	u16 eic = vcpu->arch.sie_block->eic;
+	struct kvm_s390_irq irq;
+	psw_t newpsw;
+	int rc;
+
+	vcpu->stat.exit_external_interrupt++;
+
+	rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
+	if (rc)
+		return rc;
+	/* We can not handle clock comparator or timer interrupt with bad PSW */
+	if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
+	    (newpsw.mask & PSW_MASK_EXT))
+		return -EOPNOTSUPP;
+
+	switch (eic) {
+	case EXT_IRQ_CLK_COMP:
+		irq.type = KVM_S390_INT_CLOCK_COMP;
+		break;
+	case EXT_IRQ_CPU_TIMER:
+		irq.type = KVM_S390_INT_CPU_TIMER;
+		break;
+	case EXT_IRQ_EXTERNAL_CALL:
+		irq.type = KVM_S390_INT_EXTERNAL_CALL;
+		irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
+		rc = kvm_s390_inject_vcpu(vcpu, &irq);
+		/* ignore if another external call is already pending */
+		if (rc == -EBUSY)
+			return 0;
+		return rc;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return kvm_s390_inject_vcpu(vcpu, &irq);
+}
+
+/**
+ * Handle MOVE PAGE partial execution interception.
+ *
+ * This interception can only happen for guests with DAT disabled and
+ * addresses that are currently not mapped in the host. Thus we try to
+ * set up the mappings for the corresponding user pages here (or throw
+ * addressing exceptions in case of illegal guest addresses).
+ */
+static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
+{
+	unsigned long srcaddr, dstaddr;
+	int reg1, reg2, rc;
+
+	kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
+
+	/* Make sure that the source is paged-in */
+	rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2],
+				     reg2, &srcaddr, GACC_FETCH);
+	if (rc)
+		return kvm_s390_inject_prog_cond(vcpu, rc);
+	rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
+	if (rc != 0)
+		return rc;
+
+	/* Make sure that the destination is paged-in */
+	rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1],
+				     reg1, &dstaddr, GACC_STORE);
+	if (rc)
+		return kvm_s390_inject_prog_cond(vcpu, rc);
+	rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
+	if (rc != 0)
+		return rc;
+
+	kvm_s390_retry_instr(vcpu);
+
+	return 0;
+}
+
+static int handle_partial_execution(struct kvm_vcpu *vcpu)
+{
+	vcpu->stat.exit_pei++;
+
+	if (vcpu->arch.sie_block->ipa == 0xb254)	/* MVPG */
+		return handle_mvpg_pei(vcpu);
+	if (vcpu->arch.sie_block->ipa >> 8 == 0xae)	/* SIGP */
+		return kvm_s390_handle_sigp_pei(vcpu);
+
+	return -EOPNOTSUPP;
+}
+
+/*
+ * Handle the sthyi instruction that provides the guest with system
+ * information, like current CPU resources available at each level of
+ * the machine.
+ */
+int handle_sthyi(struct kvm_vcpu *vcpu)
+{
+	int reg1, reg2, r = 0;
+	u64 code, addr, cc = 0, rc = 0;
+	struct sthyi_sctns *sctns = NULL;
+
+	if (!test_kvm_facility(vcpu->kvm, 74))
+		return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
+
+	kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
+	code = vcpu->run->s.regs.gprs[reg1];
+	addr = vcpu->run->s.regs.gprs[reg2];
+
+	vcpu->stat.instruction_sthyi++;
+	VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr);
+	trace_kvm_s390_handle_sthyi(vcpu, code, addr);
+
+	if (reg1 == reg2 || reg1 & 1 || reg2 & 1)
+		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+	if (code & 0xffff) {
+		cc = 3;
+		rc = 4;
+		goto out;
+	}
+
+	if (addr & ~PAGE_MASK)
+		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+	sctns = (void *)get_zeroed_page(GFP_KERNEL);
+	if (!sctns)
+		return -ENOMEM;
+
+	cc = sthyi_fill(sctns, &rc);
+
+out:
+	if (!cc) {
+		r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE);
+		if (r) {
+			free_page((unsigned long)sctns);
+			return kvm_s390_inject_prog_cond(vcpu, r);
+		}
+	}
+
+	free_page((unsigned long)sctns);
+	vcpu->run->s.regs.gprs[reg2 + 1] = rc;
+	kvm_s390_set_psw_cc(vcpu, cc);
+	return r;
+}
+
+static int handle_operexc(struct kvm_vcpu *vcpu)
+{
+	psw_t oldpsw, newpsw;
+	int rc;
+
+	vcpu->stat.exit_operation_exception++;
+	trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa,
+				      vcpu->arch.sie_block->ipb);
+
+	if (vcpu->arch.sie_block->ipa == 0xb256)
+		return handle_sthyi(vcpu);
+
+	if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0)
+		return -EOPNOTSUPP;
+	rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &newpsw, sizeof(psw_t));
+	if (rc)
+		return rc;
+	/*
+	 * Avoid endless loops of operation exceptions, if the pgm new
+	 * PSW will cause a new operation exception.
+	 * The heuristic checks if the pgm new psw is within 6 bytes before
+	 * the faulting psw address (with same DAT, AS settings) and the
+	 * new psw is not a wait psw and the fault was not triggered by
+	 * problem state.
+	 */
+	oldpsw = vcpu->arch.sie_block->gpsw;
+	if (oldpsw.addr - newpsw.addr <= 6 &&
+	    !(newpsw.mask & PSW_MASK_WAIT) &&
+	    !(oldpsw.mask & PSW_MASK_PSTATE) &&
+	    (newpsw.mask & PSW_MASK_ASC) == (oldpsw.mask & PSW_MASK_ASC) &&
+	    (newpsw.mask & PSW_MASK_DAT) == (oldpsw.mask & PSW_MASK_DAT))
+		return -EOPNOTSUPP;
+
+	return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
+}
+
+int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
+{
+	int rc, per_rc = 0;
+
+	if (kvm_is_ucontrol(vcpu->kvm))
+		return -EOPNOTSUPP;
+
+	switch (vcpu->arch.sie_block->icptcode) {
+	case ICPT_EXTREQ:
+		vcpu->stat.exit_external_request++;
+		return 0;
+	case ICPT_IOREQ:
+		vcpu->stat.exit_io_request++;
+		return 0;
+	case ICPT_INST:
+		rc = handle_instruction(vcpu);
+		break;
+	case ICPT_PROGI:
+		return handle_prog(vcpu);
+	case ICPT_EXTINT:
+		return handle_external_interrupt(vcpu);
+	case ICPT_WAIT:
+		return kvm_s390_handle_wait(vcpu);
+	case ICPT_VALIDITY:
+		return handle_validity(vcpu);
+	case ICPT_STOP:
+		return handle_stop(vcpu);
+	case ICPT_OPEREXC:
+		rc = handle_operexc(vcpu);
+		break;
+	case ICPT_PARTEXEC:
+		rc = handle_partial_execution(vcpu);
+		break;
+	case ICPT_KSS:
+		rc = kvm_s390_skey_check_enable(vcpu);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	/* process PER, also if the instrution is processed in user space */
+	if (vcpu->arch.sie_block->icptstatus & 0x02 &&
+	    (!rc || rc == -EOPNOTSUPP))
+		per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu);
+	return per_rc ? per_rc : rc;
+}