Adding upstream version 4.19.249.upstream/4.19.249

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

1 files changed, 187 insertions, 0 deletions

diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c
new file mode 100644
index 000000000..910bd8dab
--- /dev/null
+++ b/arch/arm/kvm/handle_exit.c
@@ -0,0 +1,187 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_coproc.h>
+#include <asm/kvm_mmu.h>
+#include <kvm/arm_psci.h>
+#include <trace/events/kvm.h>
+
+#include "trace.h"
+
+typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
+
+static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	int ret;
+
+	trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0),
+		      kvm_vcpu_hvc_get_imm(vcpu));
+	vcpu->stat.hvc_exit_stat++;
+
+	ret = kvm_hvc_call_handler(vcpu);
+	if (ret < 0) {
+		vcpu_set_reg(vcpu, 0, ~0UL);
+		return 1;
+	}
+
+	return ret;
+}
+
+static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	/*
+	 * "If an SMC instruction executed at Non-secure EL1 is
+	 * trapped to EL2 because HCR_EL2.TSC is 1, the exception is a
+	 * Trap exception, not a Secure Monitor Call exception [...]"
+	 *
+	 * We need to advance the PC after the trap, as it would
+	 * otherwise return to the same address...
+	 */
+	vcpu_set_reg(vcpu, 0, ~0UL);
+	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+	return 1;
+}
+
+/**
+ * kvm_handle_wfx - handle a WFI or WFE instructions trapped in guests
+ * @vcpu:	the vcpu pointer
+ * @run:	the kvm_run structure pointer
+ *
+ * WFE: Yield the CPU and come back to this vcpu when the scheduler
+ * decides to.
+ * WFI: Simply call kvm_vcpu_block(), which will halt execution of
+ * world-switches and schedule other host processes until there is an
+ * incoming IRQ or FIQ to the VM.
+ */
+static int kvm_handle_wfx(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	if (kvm_vcpu_get_hsr(vcpu) & HSR_WFI_IS_WFE) {
+		trace_kvm_wfx(*vcpu_pc(vcpu), true);
+		vcpu->stat.wfe_exit_stat++;
+		kvm_vcpu_on_spin(vcpu, vcpu_mode_priv(vcpu));
+	} else {
+		trace_kvm_wfx(*vcpu_pc(vcpu), false);
+		vcpu->stat.wfi_exit_stat++;
+		kvm_vcpu_block(vcpu);
+		kvm_clear_request(KVM_REQ_UNHALT, vcpu);
+	}
+
+	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+
+	return 1;
+}
+
+static int kvm_handle_unknown_ec(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	u32 hsr = kvm_vcpu_get_hsr(vcpu);
+
+	kvm_pr_unimpl("Unknown exception class: hsr: %#08x\n",
+		      hsr);
+
+	kvm_inject_undefined(vcpu);
+	return 1;
+}
+
+static exit_handle_fn arm_exit_handlers[] = {
+	[0 ... HSR_EC_MAX]	= kvm_handle_unknown_ec,
+	[HSR_EC_WFI]		= kvm_handle_wfx,
+	[HSR_EC_CP15_32]	= kvm_handle_cp15_32,
+	[HSR_EC_CP15_64]	= kvm_handle_cp15_64,
+	[HSR_EC_CP14_MR]	= kvm_handle_cp14_32,
+	[HSR_EC_CP14_LS]	= kvm_handle_cp14_load_store,
+	[HSR_EC_CP14_64]	= kvm_handle_cp14_64,
+	[HSR_EC_CP_0_13]	= kvm_handle_cp_0_13_access,
+	[HSR_EC_CP10_ID]	= kvm_handle_cp10_id,
+	[HSR_EC_HVC]		= handle_hvc,
+	[HSR_EC_SMC]		= handle_smc,
+	[HSR_EC_IABT]		= kvm_handle_guest_abort,
+	[HSR_EC_DABT]		= kvm_handle_guest_abort,
+};
+
+static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
+{
+	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
+
+	return arm_exit_handlers[hsr_ec];
+}
+
+/*
+ * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
+ * proper exit to userspace.
+ */
+int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
+		       int exception_index)
+{
+	exit_handle_fn exit_handler;
+
+	if (ARM_ABORT_PENDING(exception_index)) {
+		u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
+
+		/*
+		 * HVC/SMC already have an adjusted PC, which we need
+		 * to correct in order to return to after having
+		 * injected the abort.
+		 */
+		if (hsr_ec == HSR_EC_HVC || hsr_ec == HSR_EC_SMC) {
+			u32 adj =  kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2;
+			*vcpu_pc(vcpu) -= adj;
+		}
+
+		kvm_inject_vabt(vcpu);
+		return 1;
+	}
+
+	exception_index = ARM_EXCEPTION_CODE(exception_index);
+
+	switch (exception_index) {
+	case ARM_EXCEPTION_IRQ:
+		return 1;
+	case ARM_EXCEPTION_HVC:
+		/*
+		 * See ARM ARM B1.14.1: "Hyp traps on instructions
+		 * that fail their condition code check"
+		 */
+		if (!kvm_condition_valid(vcpu)) {
+			kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+			return 1;
+		}
+
+		exit_handler = kvm_get_exit_handler(vcpu);
+
+		return exit_handler(vcpu, run);
+	case ARM_EXCEPTION_DATA_ABORT:
+		kvm_inject_vabt(vcpu);
+		return 1;
+	case ARM_EXCEPTION_HYP_GONE:
+		/*
+		 * HYP has been reset to the hyp-stub. This happens
+		 * when a guest is pre-empted by kvm_reboot()'s
+		 * shutdown call.
+		 */
+		run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+		return 0;
+	default:
+		kvm_pr_unimpl("Unsupported exception type: %d",
+			      exception_index);
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		return 0;
+	}
+}