path: root/arch/powerpc/kvm/book3s_64_mmu_hv.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 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
 */

#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/hugetlb.h>
#include <linux/vmalloc.h>

#include <asm/tlbflush.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/mmu-hash64.h>
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
#include <asm/cputable.h>

/* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */
#define MAX_LPID_970	63

/* Power architecture requires HPT is at least 256kB */
#define PPC_MIN_HPT_ORDER	18

long kvmppc_alloc_hpt(struct kvm *kvm, u32 *htab_orderp)
{
	unsigned long hpt;
	struct revmap_entry *rev;
	struct kvmppc_linear_info *li;
	long order = kvm_hpt_order;

	if (htab_orderp) {
		order = *htab_orderp;
		if (order < PPC_MIN_HPT_ORDER)
			order = PPC_MIN_HPT_ORDER;
	}

	/*
	 * If the user wants a different size from default,
	 * try first to allocate it from the kernel page allocator.
	 */
	hpt = 0;
	if (order != kvm_hpt_order) {
		hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT|
				       __GFP_NOWARN, order - PAGE_SHIFT);
		if (!hpt)
			--order;
	}

	/* Next try to allocate from the preallocated pool */
	if (!hpt) {
		li = kvm_alloc_hpt();
		if (li) {
			hpt = (ulong)li->base_virt;
			kvm->arch.hpt_li = li;
			order = kvm_hpt_order;
		}
	}

	/* Lastly try successively smaller sizes from the page allocator */
	while (!hpt && order > PPC_MIN_HPT_ORDER) {
		hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT|
				       __GFP_NOWARN, order - PAGE_SHIFT);
		if (!hpt)
			--order;
	}

	if (!hpt)
		return -ENOMEM;

	kvm->arch.hpt_virt = hpt;
	kvm->arch.hpt_order = order;
	/* HPTEs are 2**4 bytes long */
	kvm->arch.hpt_npte = 1ul << (order - 4);
	/* 128 (2**7) bytes in each HPTEG */
	kvm->arch.hpt_mask = (1ul << (order - 7)) - 1;

	/* Allocate reverse map array */
	rev = vmalloc(sizeof(struct revmap_entry) * kvm->arch.hpt_npte);
	if (!rev) {
		pr_err("kvmppc_alloc_hpt: Couldn't alloc reverse map array\n");
		goto out_freehpt;
	}
	kvm->arch.revmap = rev;
	kvm->arch.sdr1 = __pa(hpt) | (order - 18);

	pr_info("KVM guest htab at %lx (order %ld), LPID %x\n",
		hpt, order, kvm->arch.lpid);

	if (htab_orderp)
		*htab_orderp = order;
	return 0;

 out_freehpt:
	if (kvm->arch.hpt_li)
		kvm_release_hpt(kvm->arch.hpt_li);
	else
		free_pages(hpt, order - PAGE_SHIFT);
	return -ENOMEM;
}

long kvmppc_alloc_reset_hpt(struct kvm *kvm, u32 *htab_orderp)
{
	long err = -EBUSY;
	long order;

	mutex_lock(&kvm->lock);
	if (kvm->arch.rma_setup_done) {
		kvm->arch.rma_setup_done = 0;
		/* order rma_setup_done vs. vcpus_running */
		smp_mb();
		if (