arch/powerpc/kvm/booke_host.c

/*
 * 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.
 *
 * Copyright IBM Corp. 2008
 *
 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
 */

#include <linux/errno.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <asm/cacheflush.h>
#include <asm/kvm_ppc.h>

unsigned long kvmppc_booke_handlers;

static int kvmppc_booke_init(void)
{
	unsigned long ivor[16];
	unsigned long max_ivor = 0;
	int i;

	/* We install our own exception handlers by hijacking IVPR. IVPR must
	 * be 16-bit aligned, so we need a 64KB allocation. */
	kvmppc_booke_handlers = __get_free_pages(GFP_KERNEL | __GFP_ZERO,
	                                         VCPU_SIZE_ORDER);
	if (!kvmppc_booke_handlers)
		return -ENOMEM;

	/* XXX make sure our handlers are smaller than Linux's */

	/* Copy our interrupt handlers to match host IVORs. That way we don't
	 * have to swap the IVORs on every guest/host transition. */
	ivor[0] = mfspr(SPRN_IVOR0);
	ivor[1] = mfspr(SPRN_IVOR1);
	ivor[2] = mfspr(SPRN_IVOR2);
	ivor[3] = mfspr(SPRN_IVOR3);
	ivor[4] = mfspr(SPRN_IVOR4);
	ivor[5] = mfspr(SPRN_IVOR5);
	ivor[6] = mfspr(SPRN_IVOR6);
	ivor[7] = mfspr(SPRN_IVOR7);
	ivor[8] = mfspr(SPRN_IVOR8);
	ivor[9] = mfspr(SPRN_IVOR9);
	ivor[10] = mfspr(SPRN_IVOR10);
	ivor[11] = mfspr(SPRN_IVOR11);
	ivor[12] = mfspr(SPRN_IVOR12);
	ivor[13] = mfspr(SPRN_IVOR13);
	ivor[14] = mfspr(SPRN_IVOR14);
	ivor[15] = mfspr(SPRN_IVOR15);

	for (i = 0; i < 16; i++) {
		if (ivor[i] > max_ivor)
			max_ivor = ivor[i];

		memcpy((void *)kvmppc_booke_handlers + ivor[i],
		       kvmppc_handlers_start + i * kvmppc_handler_len,
		       kvmppc_handler_len);
	}
	flush_icache_range(kvmppc_booke_handlers,
	                   kvmppc_booke_handlers + max_ivor + kvmppc_handler_len);

	return kvm_init(NULL, sizeof(struct kvm_vcpu), THIS_MODULE);
}

static void __exit kvmppc_booke_exit(void)
{
	free_pages(kvmppc_booke_handlers, VCPU_SIZE_ORDER);
	kvm_exit();
}

module_init(kvmppc_booke_init)
module_exit(kvmppc_booke_exit)