diff options
Diffstat (limited to 'arch/arm/kvm/handle_exit.c')
| -rw-r--r-- | arch/arm/kvm/handle_exit.c | 164 | 
1 files changed, 164 insertions, 0 deletions
diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c new file mode 100644 index 00000000000..3d74a0be47d --- /dev/null +++ b/arch/arm/kvm/handle_exit.c @@ -0,0 +1,164 @@ +/* + * 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 <asm/kvm_psci.h> +#include <trace/events/kvm.h> + +#include "trace.h" + +#include "trace.h" + +typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *); + +static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	/* SVC called from Hyp mode should never get here */ +	kvm_debug("SVC called from Hyp mode shouldn't go here\n"); +	BUG(); +	return -EINVAL; /* Squash warning */ +} + +static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0), +		      kvm_vcpu_hvc_get_imm(vcpu)); + +	if (kvm_psci_call(vcpu)) +		return 1; + +	kvm_inject_undefined(vcpu); +	return 1; +} + +static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	if (kvm_psci_call(vcpu)) +		return 1; + +	kvm_inject_undefined(vcpu); +	return 1; +} + +static int handle_pabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	/* The hypervisor should never cause aborts */ +	kvm_err("Prefetch Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n", +		kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu)); +	return -EFAULT; +} + +static int handle_dabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	/* This is either an error in the ws. code or an external abort */ +	kvm_err("Data Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n", +		kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu)); +	return -EFAULT; +} + +/** + * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest + * @vcpu:	the vcpu pointer + * @run:	the kvm_run structure pointer + * + * Simply sets the wait_for_interrupts flag on the vcpu structure, 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_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ +	trace_kvm_wfi(*vcpu_pc(vcpu)); +	kvm_vcpu_block(vcpu); +	return 1; +} + +static exit_handle_fn arm_exit_handlers[] = { +	[HSR_EC_WFI]		= kvm_handle_wfi, +	[HSR_EC_CP15_32]	= kvm_handle_cp15_32, +	[HSR_EC_CP15_64]	= kvm_handle_cp15_64, +	[HSR_EC_CP14_MR]	= kvm_handle_cp14_access, +	[HSR_EC_CP14_LS]	= kvm_handle_cp14_load_store, +	[HSR_EC_CP14_64]	= kvm_handle_cp14_access, +	[HSR_EC_CP_0_13]	= kvm_handle_cp_0_13_access, +	[HSR_EC_CP10_ID]	= kvm_handle_cp10_id, +	[HSR_EC_SVC_HYP]	= handle_svc_hyp, +	[HSR_EC_HVC]		= handle_hvc, +	[HSR_EC_SMC]		= handle_smc, +	[HSR_EC_IABT]		= kvm_handle_guest_abort, +	[HSR_EC_IABT_HYP]	= handle_pabt_hyp, +	[HSR_EC_DABT]		= kvm_handle_guest_abort, +	[HSR_EC_DABT_HYP]	= handle_dabt_hyp, +}; + +static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) +{ +	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu); + +	if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers) || +	    !arm_exit_handlers[hsr_ec]) { +		kvm_err("Unknown exception class: hsr: %#08x\n", +			(unsigned int)kvm_vcpu_get_hsr(vcpu)); +		BUG(); +	} + +	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; + +	switch (exception_index) { +	case ARM_EXCEPTION_IRQ: +		return 1; +	case ARM_EXCEPTION_UNDEFINED: +		kvm_err("Undefined exception in Hyp mode at: %#08lx\n", +			kvm_vcpu_get_hyp_pc(vcpu)); +		BUG(); +		panic("KVM: Hypervisor undefined exception!\n"); +	case ARM_EXCEPTION_DATA_ABORT: +	case ARM_EXCEPTION_PREF_ABORT: +	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); +	default: +		kvm_pr_unimpl("Unsupported exception type: %d", +			      exception_index); +		run->exit_reason = KVM_EXIT_INTERNAL_ERROR; +		return 0; +	} +}  |