[deliverable/linux.git] / arch / arm / kvm / handle_exit.c

/*
 * 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)
{
	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;
	}
}
Commit	Line	Data
3414bbff MZ	1	/*
	2	* Copyright (C) 2012 - Virtual Open Systems and Columbia University
	3	* Author: Christoffer Dall <c.dall@virtualopensystems.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License, version 2, as
	7	* published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	17	*/
	18
	19	#include <linux/kvm.h>
	20	#include <linux/kvm_host.h>
	21	#include <asm/kvm_emulate.h>
	22	#include <asm/kvm_coproc.h>
	23	#include <asm/kvm_mmu.h>
	24	#include <asm/kvm_psci.h>
6190920a MZ	25	#include <trace/events/kvm.h>
	26
	27	#include "trace.h"
3414bbff	28
c088f8f0 CD	29	#include "trace.h"
c088f8f0 CD	30
3414bbff MZ	31	typedef int (exit_handle_fn)(struct kvm_vcpu , struct kvm_run *);
	32
	33	static int handle_svc_hyp(struct kvm_vcpu vcpu, struct kvm_run run)
	34	{
	35	/* SVC called from Hyp mode should never get here */
	36	kvm_debug("SVC called from Hyp mode shouldn't go here\n");
	37	BUG();
	38	return -EINVAL; /* Squash warning */
	39	}
	40
	41	static int handle_hvc(struct kvm_vcpu vcpu, struct kvm_run run)
	42	{
c088f8f0 CD	43	trace_kvm_hvc(vcpu_pc(vcpu), vcpu_reg(vcpu, 0),
	44	kvm_vcpu_hvc_get_imm(vcpu));
	45
3414bbff MZ	46	if (kvm_psci_call(vcpu))
	47	return 1;
	48
	49	kvm_inject_undefined(vcpu);
	50	return 1;
	51	}
	52
	53	static int handle_smc(struct kvm_vcpu vcpu, struct kvm_run run)
	54	{
3414bbff MZ	55	kvm_inject_undefined(vcpu);
	56	return 1;
	57	}
	58
	59	static int handle_pabt_hyp(struct kvm_vcpu vcpu, struct kvm_run run)
	60	{
	61	/* The hypervisor should never cause aborts */
	62	kvm_err("Prefetch Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n",
	63	kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu));
	64	return -EFAULT;
	65	}
	66
	67	static int handle_dabt_hyp(struct kvm_vcpu vcpu, struct kvm_run run)
	68	{
	69	/* This is either an error in the ws. code or an external abort */
	70	kvm_err("Data Abort taken from Hyp mode at %#08lx (HSR: %#08x)\n",
	71	kvm_vcpu_get_hfar(vcpu), kvm_vcpu_get_hsr(vcpu));
	72	return -EFAULT;
	73	}
	74
6190920a MZ	75	/**
	76	* kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest
	77	* @vcpu: the vcpu pointer
	78	* @run: the kvm_run structure pointer
	79	*
	80	* Simply sets the wait_for_interrupts flag on the vcpu structure, which will
	81	* halt execution of world-switches and schedule other host processes until
	82	* there is an incoming IRQ or FIQ to the VM.
	83	*/
	84	static int kvm_handle_wfi(struct kvm_vcpu vcpu, struct kvm_run run)
	85	{
	86	trace_kvm_wfi(*vcpu_pc(vcpu));
	87	kvm_vcpu_block(vcpu);
	88	return 1;
	89	}
	90
3414bbff MZ	91	static exit_handle_fn arm_exit_handlers[] = {
	92	[HSR_EC_WFI] = kvm_handle_wfi,
	93	[HSR_EC_CP15_32] = kvm_handle_cp15_32,
	94	[HSR_EC_CP15_64] = kvm_handle_cp15_64,
	95	[HSR_EC_CP14_MR] = kvm_handle_cp14_access,
	96	[HSR_EC_CP14_LS] = kvm_handle_cp14_load_store,
	97	[HSR_EC_CP14_64] = kvm_handle_cp14_access,
	98	[HSR_EC_CP_0_13] = kvm_handle_cp_0_13_access,
	99	[HSR_EC_CP10_ID] = kvm_handle_cp10_id,
	100	[HSR_EC_SVC_HYP] = handle_svc_hyp,
	101	[HSR_EC_HVC] = handle_hvc,
	102	[HSR_EC_SMC] = handle_smc,
	103	[HSR_EC_IABT] = kvm_handle_guest_abort,
	104	[HSR_EC_IABT_HYP] = handle_pabt_hyp,
	105	[HSR_EC_DABT] = kvm_handle_guest_abort,
	106	[HSR_EC_DABT_HYP] = handle_dabt_hyp,
	107	};
	108
	109	static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
	110	{
	111	u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
	112
	113	if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers) \|\|
	114	!arm_exit_handlers[hsr_ec]) {
8546dc1d	115	kvm_err("Unknown exception class: hsr: %#08x\n",
3414bbff MZ	116	(unsigned int)kvm_vcpu_get_hsr(vcpu));
	117	BUG();
	118	}
	119
	120	return arm_exit_handlers[hsr_ec];
	121	}
	122
	123	/*
	124	* Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
	125	* proper exit to userspace.
	126	*/
	127	int handle_exit(struct kvm_vcpu vcpu, struct kvm_run run,
	128	int exception_index)
	129	{
	130	exit_handle_fn exit_handler;
	131
	132	switch (exception_index) {
	133	case ARM_EXCEPTION_IRQ:
	134	return 1;
	135	case ARM_EXCEPTION_UNDEFINED:
	136	kvm_err("Undefined exception in Hyp mode at: %#08lx\n",
	137	kvm_vcpu_get_hyp_pc(vcpu));
	138	BUG();
	139	panic("KVM: Hypervisor undefined exception!\n");
	140	case ARM_EXCEPTION_DATA_ABORT:
	141	case ARM_EXCEPTION_PREF_ABORT:
	142	case ARM_EXCEPTION_HVC:
	143	/*
	144	* See ARM ARM B1.14.1: "Hyp traps on instructions
	145	* that fail their condition code check"
	146	*/
	147	if (!kvm_condition_valid(vcpu)) {
	148	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
	149	return 1;
	150	}
	151
	152	exit_handler = kvm_get_exit_handler(vcpu);
	153
	154	return exit_handler(vcpu, run);
	155	default:
	156	kvm_pr_unimpl("Unsupported exception type: %d",
	157	exception_index);
	158	run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
	159	return 0;
	160	}
	161	}