1024 lines
26 KiB
C
1024 lines
26 KiB
C
/*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License, version 2, as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*
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* Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
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*/
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#include <linux/types.h>
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#include <linux/string.h>
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#include <linux/kvm.h>
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#include <linux/kvm_host.h>
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#include <linux/highmem.h>
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#include <linux/gfp.h>
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#include <linux/slab.h>
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#include <linux/hugetlb.h>
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#include <linux/vmalloc.h>
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#include <asm/tlbflush.h>
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#include <asm/kvm_ppc.h>
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#include <asm/kvm_book3s.h>
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#include <asm/mmu-hash64.h>
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#include <asm/hvcall.h>
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#include <asm/synch.h>
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#include <asm/ppc-opcode.h>
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#include <asm/cputable.h>
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/* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */
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#define MAX_LPID_970 63
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#define NR_LPIDS (LPID_RSVD + 1)
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unsigned long lpid_inuse[BITS_TO_LONGS(NR_LPIDS)];
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long kvmppc_alloc_hpt(struct kvm *kvm)
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{
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unsigned long hpt;
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unsigned long lpid;
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struct revmap_entry *rev;
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struct kvmppc_linear_info *li;
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/* Allocate guest's hashed page table */
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li = kvm_alloc_hpt();
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if (li) {
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/* using preallocated memory */
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hpt = (ulong)li->base_virt;
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kvm->arch.hpt_li = li;
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} else {
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/* using dynamic memory */
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hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT|
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__GFP_NOWARN, HPT_ORDER - PAGE_SHIFT);
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}
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if (!hpt) {
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pr_err("kvm_alloc_hpt: Couldn't alloc HPT\n");
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return -ENOMEM;
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}
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kvm->arch.hpt_virt = hpt;
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/* Allocate reverse map array */
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rev = vmalloc(sizeof(struct revmap_entry) * HPT_NPTE);
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if (!rev) {
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pr_err("kvmppc_alloc_hpt: Couldn't alloc reverse map array\n");
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goto out_freehpt;
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}
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kvm->arch.revmap = rev;
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/* Allocate the guest's logical partition ID */
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do {
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lpid = find_first_zero_bit(lpid_inuse, NR_LPIDS);
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if (lpid >= NR_LPIDS) {
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pr_err("kvm_alloc_hpt: No LPIDs free\n");
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goto out_freeboth;
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}
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} while (test_and_set_bit(lpid, lpid_inuse));
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kvm->arch.sdr1 = __pa(hpt) | (HPT_ORDER - 18);
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kvm->arch.lpid = lpid;
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pr_info("KVM guest htab at %lx, LPID %lx\n", hpt, lpid);
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return 0;
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out_freeboth:
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vfree(rev);
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out_freehpt:
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free_pages(hpt, HPT_ORDER - PAGE_SHIFT);
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return -ENOMEM;
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}
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void kvmppc_free_hpt(struct kvm *kvm)
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{
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clear_bit(kvm->arch.lpid, lpid_inuse);
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vfree(kvm->arch.revmap);
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if (kvm->arch.hpt_li)
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kvm_release_hpt(kvm->arch.hpt_li);
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else
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free_pages(kvm->arch.hpt_virt, HPT_ORDER - PAGE_SHIFT);
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}
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/* Bits in first HPTE dword for pagesize 4k, 64k or 16M */
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static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize)
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{
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return (pgsize > 0x1000) ? HPTE_V_LARGE : 0;
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}
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/* Bits in second HPTE dword for pagesize 4k, 64k or 16M */
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static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize)
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{
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return (pgsize == 0x10000) ? 0x1000 : 0;
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}
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void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot,
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unsigned long porder)
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{
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unsigned long i;
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unsigned long npages;
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unsigned long hp_v, hp_r;
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unsigned long addr, hash;
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unsigned long psize;
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unsigned long hp0, hp1;
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long ret;
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psize = 1ul << porder;
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npages = memslot->npages >> (porder - PAGE_SHIFT);
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/* VRMA can't be > 1TB */
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if (npages > 1ul << (40 - porder))
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npages = 1ul << (40 - porder);
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/* Can't use more than 1 HPTE per HPTEG */
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if (npages > HPT_NPTEG)
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npages = HPT_NPTEG;
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hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) |
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HPTE_V_BOLTED | hpte0_pgsize_encoding(psize);
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hp1 = hpte1_pgsize_encoding(psize) |
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HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX;
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for (i = 0; i < npages; ++i) {
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addr = i << porder;
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/* can't use hpt_hash since va > 64 bits */
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hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25))) & HPT_HASH_MASK;
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/*
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* We assume that the hash table is empty and no
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* vcpus are using it at this stage. Since we create
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* at most one HPTE per HPTEG, we just assume entry 7
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* is available and use it.
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*/
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hash = (hash << 3) + 7;
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hp_v = hp0 | ((addr >> 16) & ~0x7fUL);
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hp_r = hp1 | addr;
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ret = kvmppc_virtmode_h_enter(vcpu, H_EXACT, hash, hp_v, hp_r);
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if (ret != H_SUCCESS) {
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pr_err("KVM: map_vrma at %lx failed, ret=%ld\n",
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addr, ret);
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break;
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}
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}
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}
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int kvmppc_mmu_hv_init(void)
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{
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unsigned long host_lpid, rsvd_lpid;
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if (!cpu_has_feature(CPU_FTR_HVMODE))
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return -EINVAL;
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memset(lpid_inuse, 0, sizeof(lpid_inuse));
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if (cpu_has_feature(CPU_FTR_ARCH_206)) {
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host_lpid = mfspr(SPRN_LPID); /* POWER7 */
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rsvd_lpid = LPID_RSVD;
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} else {
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host_lpid = 0; /* PPC970 */
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rsvd_lpid = MAX_LPID_970;
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}
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set_bit(host_lpid, lpid_inuse);
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/* rsvd_lpid is reserved for use in partition switching */
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set_bit(rsvd_lpid, lpid_inuse);
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return 0;
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}
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void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu)
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{
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}
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static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
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{
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kvmppc_set_msr(vcpu, MSR_SF | MSR_ME);
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}
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/*
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* This is called to get a reference to a guest page if there isn't
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* one already in the kvm->arch.slot_phys[][] arrays.
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*/
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static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
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struct kvm_memory_slot *memslot,
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unsigned long psize)
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{
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unsigned long start;
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long np, err;
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struct page *page, *hpage, *pages[1];
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unsigned long s, pgsize;
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unsigned long *physp;
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unsigned int is_io, got, pgorder;
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struct vm_area_struct *vma;
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unsigned long pfn, i, npages;
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physp = kvm->arch.slot_phys[memslot->id];
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if (!physp)
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return -EINVAL;
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if (physp[gfn - memslot->base_gfn])
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return 0;
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is_io = 0;
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got = 0;
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page = NULL;
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pgsize = psize;
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err = -EINVAL;
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start = gfn_to_hva_memslot(memslot, gfn);
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/* Instantiate and get the page we want access to */
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np = get_user_pages_fast(start, 1, 1, pages);
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if (np != 1) {
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/* Look up the vma for the page */
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down_read(¤t->mm->mmap_sem);
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vma = find_vma(current->mm, start);
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if (!vma || vma->vm_start > start ||
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start + psize > vma->vm_end ||
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!(vma->vm_flags & VM_PFNMAP))
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goto up_err;
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is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot));
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pfn = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
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/* check alignment of pfn vs. requested page size */
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if (psize > PAGE_SIZE && (pfn & ((psize >> PAGE_SHIFT) - 1)))
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goto up_err;
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up_read(¤t->mm->mmap_sem);
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} else {
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page = pages[0];
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got = KVMPPC_GOT_PAGE;
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/* See if this is a large page */
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s = PAGE_SIZE;
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if (PageHuge(page)) {
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hpage = compound_head(page);
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s <<= compound_order(hpage);
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/* Get the whole large page if slot alignment is ok */
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if (s > psize && slot_is_aligned(memslot, s) &&
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!(memslot->userspace_addr & (s - 1))) {
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start &= ~(s - 1);
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pgsize = s;
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page = hpage;
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}
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}
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if (s < psize)
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goto out;
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pfn = page_to_pfn(page);
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}
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npages = pgsize >> PAGE_SHIFT;
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pgorder = __ilog2(npages);
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physp += (gfn - memslot->base_gfn) & ~(npages - 1);
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spin_lock(&kvm->arch.slot_phys_lock);
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for (i = 0; i < npages; ++i) {
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if (!physp[i]) {
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physp[i] = ((pfn + i) << PAGE_SHIFT) +
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got + is_io + pgorder;
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got = 0;
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}
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}
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spin_unlock(&kvm->arch.slot_phys_lock);
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err = 0;
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out:
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if (got) {
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if (PageHuge(page))
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page = compound_head(page);
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put_page(page);
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}
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return err;
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up_err:
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up_read(¤t->mm->mmap_sem);
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return err;
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}
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/*
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* We come here on a H_ENTER call from the guest when we are not
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* using mmu notifiers and we don't have the requested page pinned
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* already.
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*/
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long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
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long pte_index, unsigned long pteh, unsigned long ptel)
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{
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struct kvm *kvm = vcpu->kvm;
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unsigned long psize, gpa, gfn;
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struct kvm_memory_slot *memslot;
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long ret;
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if (kvm->arch.using_mmu_notifiers)
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goto do_insert;
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psize = hpte_page_size(pteh, ptel);
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if (!psize)
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return H_PARAMETER;
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pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID);
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/* Find the memslot (if any) for this address */
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gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
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gfn = gpa >> PAGE_SHIFT;
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memslot = gfn_to_memslot(kvm, gfn);
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if (memslot && !(memslot->flags & KVM_MEMSLOT_INVALID)) {
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if (!slot_is_aligned(memslot, psize))
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return H_PARAMETER;
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if (kvmppc_get_guest_page(kvm, gfn, memslot, psize) < 0)
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return H_PARAMETER;
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}
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do_insert:
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/* Protect linux PTE lookup from page table destruction */
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rcu_read_lock_sched(); /* this disables preemption too */
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vcpu->arch.pgdir = current->mm->pgd;
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ret = kvmppc_h_enter(vcpu, flags, pte_index, pteh, ptel);
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rcu_read_unlock_sched();
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if (ret == H_TOO_HARD) {
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/* this can't happen */
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pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n");
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ret = H_RESOURCE; /* or something */
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}
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return ret;
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}
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static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu,
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gva_t eaddr)
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{
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u64 mask;
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int i;
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for (i = 0; i < vcpu->arch.slb_nr; i++) {
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if (!(vcpu->arch.slb[i].orige & SLB_ESID_V))
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continue;
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if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T)
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mask = ESID_MASK_1T;
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else
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mask = ESID_MASK;
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if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0)
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return &vcpu->arch.slb[i];
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}
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return NULL;
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}
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static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r,
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unsigned long ea)
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{
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unsigned long ra_mask;
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ra_mask = hpte_page_size(v, r) - 1;
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return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask);
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}
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static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
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struct kvmppc_pte *gpte, bool data)
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{
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struct kvm *kvm = vcpu->kvm;
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struct kvmppc_slb *slbe;
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unsigned long slb_v;
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unsigned long pp, key;
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unsigned long v, gr;
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unsigned long *hptep;
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int index;
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int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);
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/* Get SLB entry */
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if (virtmode) {
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slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr);
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if (!slbe)
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return -EINVAL;
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slb_v = slbe->origv;
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} else {
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/* real mode access */
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slb_v = vcpu->kvm->arch.vrma_slb_v;
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}
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/* Find the HPTE in the hash table */
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index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v,
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HPTE_V_VALID | HPTE_V_ABSENT);
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if (index < 0)
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return -ENOENT;
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hptep = (unsigned long *)(kvm->arch.hpt_virt + (index << 4));
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v = hptep[0] & ~HPTE_V_HVLOCK;
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gr = kvm->arch.revmap[index].guest_rpte;
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/* Unlock the HPTE */
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asm volatile("lwsync" : : : "memory");
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hptep[0] = v;
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gpte->eaddr = eaddr;
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gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff);
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/* Get PP bits and key for permission check */
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pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
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key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
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key &= slb_v;
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/* Calculate permissions */
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gpte->may_read = hpte_read_permission(pp, key);
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gpte->may_write = hpte_write_permission(pp, key);
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gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G));
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/* Storage key permission check for POWER7 */
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if (data && virtmode && cpu_has_feature(CPU_FTR_ARCH_206)) {
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int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr);
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if (amrfield & 1)
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gpte->may_read = 0;
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if (amrfield & 2)
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gpte->may_write = 0;
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}
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/* Get the guest physical address */
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gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr);
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return 0;
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}
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/*
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* Quick test for whether an instruction is a load or a store.
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* If the instruction is a load or a store, then this will indicate
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* which it is, at least on server processors. (Embedded processors
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* have some external PID instructions that don't follow the rule
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* embodied here.) If the instruction isn't a load or store, then
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* this doesn't return anything useful.
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*/
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static int instruction_is_store(unsigned int instr)
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{
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unsigned int mask;
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mask = 0x10000000;
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if ((instr & 0xfc000000) == 0x7c000000)
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mask = 0x100; /* major opcode 31 */
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return (instr & mask) != 0;
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}
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static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu,
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unsigned long gpa, int is_store)
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{
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int ret;
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u32 last_inst;
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unsigned long srr0 = kvmppc_get_pc(vcpu);
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/* We try to load the last instruction. We don't let
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* emulate_instruction do it as it doesn't check what
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* kvmppc_ld returns.
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* If we fail, we just return to the guest and try executing it again.
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*/
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if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) {
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ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false);
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if (ret != EMULATE_DONE || last_inst == KVM_INST_FETCH_FAILED)
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return RESUME_GUEST;
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vcpu->arch.last_inst = last_inst;
|
|
}
|
|
|
|
/*
|
|
* WARNING: We do not know for sure whether the instruction we just
|
|
* read from memory is the same that caused the fault in the first
|
|
* place. If the instruction we read is neither an load or a store,
|
|
* then it can't access memory, so we don't need to worry about
|
|
* enforcing access permissions. So, assuming it is a load or
|
|
* store, we just check that its direction (load or store) is
|
|
* consistent with the original fault, since that's what we
|
|
* checked the access permissions against. If there is a mismatch
|
|
* we just return and retry the instruction.
|
|
*/
|
|
|
|
if (instruction_is_store(vcpu->arch.last_inst) != !!is_store)
|
|
return RESUME_GUEST;
|
|
|
|
/*
|
|
* Emulated accesses are emulated by looking at the hash for
|
|
* translation once, then performing the access later. The
|
|
* translation could be invalidated in the meantime in which
|
|
* point performing the subsequent memory access on the old
|
|
* physical address could possibly be a security hole for the
|
|
* guest (but not the host).
|
|
*
|
|
* This is less of an issue for MMIO stores since they aren't
|
|
* globally visible. It could be an issue for MMIO loads to
|
|
* a certain extent but we'll ignore it for now.
|
|
*/
|
|
|
|
vcpu->arch.paddr_accessed = gpa;
|
|
return kvmppc_emulate_mmio(run, vcpu);
|
|
}
|
|
|
|
int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
|
|
unsigned long ea, unsigned long dsisr)
|
|
{
|
|
struct kvm *kvm = vcpu->kvm;
|
|
unsigned long *hptep, hpte[3], r;
|
|
unsigned long mmu_seq, psize, pte_size;
|
|
unsigned long gfn, hva, pfn;
|
|
struct kvm_memory_slot *memslot;
|
|
unsigned long *rmap;
|
|
struct revmap_entry *rev;
|
|
struct page *page, *pages[1];
|
|
long index, ret, npages;
|
|
unsigned long is_io;
|
|
unsigned int writing, write_ok;
|
|
struct vm_area_struct *vma;
|
|
unsigned long rcbits;
|
|
|
|
/*
|
|
* Real-mode code has already searched the HPT and found the
|
|
* entry we're interested in. Lock the entry and check that
|
|
* it hasn't changed. If it has, just return and re-execute the
|
|
* instruction.
|
|
*/
|
|
if (ea != vcpu->arch.pgfault_addr)
|
|
return RESUME_GUEST;
|
|
index = vcpu->arch.pgfault_index;
|
|
hptep = (unsigned long *)(kvm->arch.hpt_virt + (index << 4));
|
|
rev = &kvm->arch.revmap[index];
|
|
preempt_disable();
|
|
while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
|
|
cpu_relax();
|
|
hpte[0] = hptep[0] & ~HPTE_V_HVLOCK;
|
|
hpte[1] = hptep[1];
|
|
hpte[2] = r = rev->guest_rpte;
|
|
asm volatile("lwsync" : : : "memory");
|
|
hptep[0] = hpte[0];
|
|
preempt_enable();
|
|
|
|
if (hpte[0] != vcpu->arch.pgfault_hpte[0] ||
|
|
hpte[1] != vcpu->arch.pgfault_hpte[1])
|
|
return RESUME_GUEST;
|
|
|
|
/* Translate the logical address and get the page */
|
|
psize = hpte_page_size(hpte[0], r);
|
|
gfn = hpte_rpn(r, psize);
|
|
memslot = gfn_to_memslot(kvm, gfn);
|
|
|
|
/* No memslot means it's an emulated MMIO region */
|
|
if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
|
|
unsigned long gpa = (gfn << PAGE_SHIFT) | (ea & (psize - 1));
|
|
return kvmppc_hv_emulate_mmio(run, vcpu, gpa,
|
|
dsisr & DSISR_ISSTORE);
|
|
}
|
|
|
|
if (!kvm->arch.using_mmu_notifiers)
|
|
return -EFAULT; /* should never get here */
|
|
|
|
/* used to check for invalidations in progress */
|
|
mmu_seq = kvm->mmu_notifier_seq;
|
|
smp_rmb();
|
|
|
|
is_io = 0;
|
|
pfn = 0;
|
|
page = NULL;
|
|
pte_size = PAGE_SIZE;
|
|
writing = (dsisr & DSISR_ISSTORE) != 0;
|
|
/* If writing != 0, then the HPTE must allow writing, if we get here */
|
|
write_ok = writing;
|
|
hva = gfn_to_hva_memslot(memslot, gfn);
|
|
npages = get_user_pages_fast(hva, 1, writing, pages);
|
|
if (npages < 1) {
|
|
/* Check if it's an I/O mapping */
|
|
down_read(¤t->mm->mmap_sem);
|
|
vma = find_vma(current->mm, hva);
|
|
if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end &&
|
|
(vma->vm_flags & VM_PFNMAP)) {
|
|
pfn = vma->vm_pgoff +
|
|
((hva - vma->vm_start) >> PAGE_SHIFT);
|
|
pte_size = psize;
|
|
is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot));
|
|
write_ok = vma->vm_flags & VM_WRITE;
|
|
}
|
|
up_read(¤t->mm->mmap_sem);
|
|
if (!pfn)
|
|
return -EFAULT;
|
|
} else {
|
|
page = pages[0];
|
|
if (PageHuge(page)) {
|
|
page = compound_head(page);
|
|
pte_size <<= compound_order(page);
|
|
}
|
|
/* if the guest wants write access, see if that is OK */
|
|
if (!writing && hpte_is_writable(r)) {
|
|
pte_t *ptep, pte;
|
|
|
|
/*
|
|
* We need to protect against page table destruction
|
|
* while looking up and updating the pte.
|
|
*/
|
|
rcu_read_lock_sched();
|
|
ptep = find_linux_pte_or_hugepte(current->mm->pgd,
|
|
hva, NULL);
|
|
if (ptep && pte_present(*ptep)) {
|
|
pte = kvmppc_read_update_linux_pte(ptep, 1);
|
|
if (pte_write(pte))
|
|
write_ok = 1;
|
|
}
|
|
rcu_read_unlock_sched();
|
|
}
|
|
pfn = page_to_pfn(page);
|
|
}
|
|
|
|
ret = -EFAULT;
|
|
if (psize > pte_size)
|
|
goto out_put;
|
|
|
|
/* Check WIMG vs. the actual page we're accessing */
|
|
if (!hpte_cache_flags_ok(r, is_io)) {
|
|
if (is_io)
|
|
return -EFAULT;
|
|
/*
|
|
* Allow guest to map emulated device memory as
|
|
* uncacheable, but actually make it cacheable.
|
|
*/
|
|
r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M;
|
|
}
|
|
|
|
/* Set the HPTE to point to pfn */
|
|
r = (r & ~(HPTE_R_PP0 - pte_size)) | (pfn << PAGE_SHIFT);
|
|
if (hpte_is_writable(r) && !write_ok)
|
|
r = hpte_make_readonly(r);
|
|
ret = RESUME_GUEST;
|
|
preempt_disable();
|
|
while (!try_lock_hpte(hptep, HPTE_V_HVLOCK))
|
|
cpu_relax();
|
|
if ((hptep[0] & ~HPTE_V_HVLOCK) != hpte[0] || hptep[1] != hpte[1] ||
|
|
rev->guest_rpte != hpte[2])
|
|
/* HPTE has been changed under us; let the guest retry */
|
|
goto out_unlock;
|
|
hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
|
|
|
|
rmap = &memslot->rmap[gfn - memslot->base_gfn];
|
|
lock_rmap(rmap);
|
|
|
|
/* Check if we might have been invalidated; let the guest retry if so */
|
|
ret = RESUME_GUEST;
|
|
if (mmu_notifier_retry(vcpu, mmu_seq)) {
|
|
unlock_rmap(rmap);
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* Only set R/C in real HPTE if set in both *rmap and guest_rpte */
|
|
rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
|
|
r &= rcbits | ~(HPTE_R_R | HPTE_R_C);
|
|
|
|
if (hptep[0] & HPTE_V_VALID) {
|
|
/* HPTE was previously valid, so we need to invalidate it */
|
|
unlock_rmap(rmap);
|
|
hptep[0] |= HPTE_V_ABSENT;
|
|
kvmppc_invalidate_hpte(kvm, hptep, index);
|
|
/* don't lose previous R and C bits */
|
|
r |= hptep[1] & (HPTE_R_R | HPTE_R_C);
|
|
} else {
|
|
kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0);
|
|
}
|
|
|
|
hptep[1] = r;
|
|
eieio();
|
|
hptep[0] = hpte[0];
|
|
asm volatile("ptesync" : : : "memory");
|
|
preempt_enable();
|
|
if (page && hpte_is_writable(r))
|
|
SetPageDirty(page);
|
|
|
|
out_put:
|
|
if (page)
|
|
put_page(page);
|
|
return ret;
|
|
|
|
out_unlock:
|
|
hptep[0] &= ~HPTE_V_HVLOCK;
|
|
preempt_enable();
|
|
goto out_put;
|
|
}
|
|
|
|
static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
|
|
int (*handler)(struct kvm *kvm, unsigned long *rmapp,
|
|
unsigned long gfn))
|
|
{
|
|
int ret;
|
|
int retval = 0;
|
|
struct kvm_memslots *slots;
|
|
struct kvm_memory_slot *memslot;
|
|
|
|
slots = kvm_memslots(kvm);
|
|
kvm_for_each_memslot(memslot, slots) {
|
|
unsigned long start = memslot->userspace_addr;
|
|
unsigned long end;
|
|
|
|
end = start + (memslot->npages << PAGE_SHIFT);
|
|
if (hva >= start && hva < end) {
|
|
gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT;
|
|
|
|
ret = handler(kvm, &memslot->rmap[gfn_offset],
|
|
memslot->base_gfn + gfn_offset);
|
|
retval |= ret;
|
|
}
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp,
|
|
unsigned long gfn)
|
|
{
|
|
struct revmap_entry *rev = kvm->arch.revmap;
|
|
unsigned long h, i, j;
|
|
unsigned long *hptep;
|
|
unsigned long ptel, psize, rcbits;
|
|
|
|
for (;;) {
|
|
lock_rmap(rmapp);
|
|
if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
|
|
unlock_rmap(rmapp);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* To avoid an ABBA deadlock with the HPTE lock bit,
|
|
* we can't spin on the HPTE lock while holding the
|
|
* rmap chain lock.
|
|
*/
|
|
i = *rmapp & KVMPPC_RMAP_INDEX;
|
|
hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4));
|
|
if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
|
|
/* unlock rmap before spinning on the HPTE lock */
|
|
unlock_rmap(rmapp);
|
|
while (hptep[0] & HPTE_V_HVLOCK)
|
|
cpu_relax();
|
|
continue;
|
|
}
|
|
j = rev[i].forw;
|
|
if (j == i) {
|
|
/* chain is now empty */
|
|
*rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
|
|
} else {
|
|
/* remove i from chain */
|
|
h = rev[i].back;
|
|
rev[h].forw = j;
|
|
rev[j].back = h;
|
|
rev[i].forw = rev[i].back = i;
|
|
*rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j;
|
|
}
|
|
|
|
/* Now check and modify the HPTE */
|
|
ptel = rev[i].guest_rpte;
|
|
psize = hpte_page_size(hptep[0], ptel);
|
|
if ((hptep[0] & HPTE_V_VALID) &&
|
|
hpte_rpn(ptel, psize) == gfn) {
|
|
hptep[0] |= HPTE_V_ABSENT;
|
|
kvmppc_invalidate_hpte(kvm, hptep, i);
|
|
/* Harvest R and C */
|
|
rcbits = hptep[1] & (HPTE_R_R | HPTE_R_C);
|
|
*rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT;
|
|
rev[i].guest_rpte = ptel | rcbits;
|
|
}
|
|
unlock_rmap(rmapp);
|
|
hptep[0] &= ~HPTE_V_HVLOCK;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
|
|
{
|
|
if (kvm->arch.using_mmu_notifiers)
|
|
kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
|
|
unsigned long gfn)
|
|
{
|
|
struct revmap_entry *rev = kvm->arch.revmap;
|
|
unsigned long head, i, j;
|
|
unsigned long *hptep;
|
|
int ret = 0;
|
|
|
|
retry:
|
|
lock_rmap(rmapp);
|
|
if (*rmapp & KVMPPC_RMAP_REFERENCED) {
|
|
*rmapp &= ~KVMPPC_RMAP_REFERENCED;
|
|
ret = 1;
|
|
}
|
|
if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
|
|
unlock_rmap(rmapp);
|
|
return ret;
|
|
}
|
|
|
|
i = head = *rmapp & KVMPPC_RMAP_INDEX;
|
|
do {
|
|
hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4));
|
|
j = rev[i].forw;
|
|
|
|
/* If this HPTE isn't referenced, ignore it */
|
|
if (!(hptep[1] & HPTE_R_R))
|
|
continue;
|
|
|
|
if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
|
|
/* unlock rmap before spinning on the HPTE lock */
|
|
unlock_rmap(rmapp);
|
|
while (hptep[0] & HPTE_V_HVLOCK)
|
|
cpu_relax();
|
|
goto retry;
|
|
}
|
|
|
|
/* Now check and modify the HPTE */
|
|
if ((hptep[0] & HPTE_V_VALID) && (hptep[1] & HPTE_R_R)) {
|
|
kvmppc_clear_ref_hpte(kvm, hptep, i);
|
|
rev[i].guest_rpte |= HPTE_R_R;
|
|
ret = 1;
|
|
}
|
|
hptep[0] &= ~HPTE_V_HVLOCK;
|
|
} while ((i = j) != head);
|
|
|
|
unlock_rmap(rmapp);
|
|
return ret;
|
|
}
|
|
|
|
int kvm_age_hva(struct kvm *kvm, unsigned long hva)
|
|
{
|
|
if (!kvm->arch.using_mmu_notifiers)
|
|
return 0;
|
|
return kvm_handle_hva(kvm, hva, kvm_age_rmapp);
|
|
}
|
|
|
|
static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
|
|
unsigned long gfn)
|
|
{
|
|
struct revmap_entry *rev = kvm->arch.revmap;
|
|
unsigned long head, i, j;
|
|
unsigned long *hp;
|
|
int ret = 1;
|
|
|
|
if (*rmapp & KVMPPC_RMAP_REFERENCED)
|
|
return 1;
|
|
|
|
lock_rmap(rmapp);
|
|
if (*rmapp & KVMPPC_RMAP_REFERENCED)
|
|
goto out;
|
|
|
|
if (*rmapp & KVMPPC_RMAP_PRESENT) {
|
|
i = head = *rmapp & KVMPPC_RMAP_INDEX;
|
|
do {
|
|
hp = (unsigned long *)(kvm->arch.hpt_virt + (i << 4));
|
|
j = rev[i].forw;
|
|
if (hp[1] & HPTE_R_R)
|
|
goto out;
|
|
} while ((i = j) != head);
|
|
}
|
|
ret = 0;
|
|
|
|
out:
|
|
unlock_rmap(rmapp);
|
|
return ret;
|
|
}
|
|
|
|
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
|
|
{
|
|
if (!kvm->arch.using_mmu_notifiers)
|
|
return 0;
|
|
return kvm_handle_hva(kvm, hva, kvm_test_age_rmapp);
|
|
}
|
|
|
|
void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
|
|
{
|
|
if (!kvm->arch.using_mmu_notifiers)
|
|
return;
|
|
kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
|
|
}
|
|
|
|
static int kvm_test_clear_dirty(struct kvm *kvm, unsigned long *rmapp)
|
|
{
|
|
struct revmap_entry *rev = kvm->arch.revmap;
|
|
unsigned long head, i, j;
|
|
unsigned long *hptep;
|
|
int ret = 0;
|
|
|
|
retry:
|
|
lock_rmap(rmapp);
|
|
if (*rmapp & KVMPPC_RMAP_CHANGED) {
|
|
*rmapp &= ~KVMPPC_RMAP_CHANGED;
|
|
ret = 1;
|
|
}
|
|
if (!(*rmapp & KVMPPC_RMAP_PRESENT)) {
|
|
unlock_rmap(rmapp);
|
|
return ret;
|
|
}
|
|
|
|
i = head = *rmapp & KVMPPC_RMAP_INDEX;
|
|
do {
|
|
hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4));
|
|
j = rev[i].forw;
|
|
|
|
if (!(hptep[1] & HPTE_R_C))
|
|
continue;
|
|
|
|
if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) {
|
|
/* unlock rmap before spinning on the HPTE lock */
|
|
unlock_rmap(rmapp);
|
|
while (hptep[0] & HPTE_V_HVLOCK)
|
|
cpu_relax();
|
|
goto retry;
|
|
}
|
|
|
|
/* Now check and modify the HPTE */
|
|
if ((hptep[0] & HPTE_V_VALID) && (hptep[1] & HPTE_R_C)) {
|
|
/* need to make it temporarily absent to clear C */
|
|
hptep[0] |= HPTE_V_ABSENT;
|
|
kvmppc_invalidate_hpte(kvm, hptep, i);
|
|
hptep[1] &= ~HPTE_R_C;
|
|
eieio();
|
|
hptep[0] = (hptep[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID;
|
|
rev[i].guest_rpte |= HPTE_R_C;
|
|
ret = 1;
|
|
}
|
|
hptep[0] &= ~HPTE_V_HVLOCK;
|
|
} while ((i = j) != head);
|
|
|
|
unlock_rmap(rmapp);
|
|
return ret;
|
|
}
|
|
|
|
long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
|
|
{
|
|
unsigned long i;
|
|
unsigned long *rmapp, *map;
|
|
|
|
preempt_disable();
|
|
rmapp = memslot->rmap;
|
|
map = memslot->dirty_bitmap;
|
|
for (i = 0; i < memslot->npages; ++i) {
|
|
if (kvm_test_clear_dirty(kvm, rmapp))
|
|
__set_bit_le(i, map);
|
|
++rmapp;
|
|
}
|
|
preempt_enable();
|
|
return 0;
|
|
}
|
|
|
|
void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
|
|
unsigned long *nb_ret)
|
|
{
|
|
struct kvm_memory_slot *memslot;
|
|
unsigned long gfn = gpa >> PAGE_SHIFT;
|
|
struct page *page, *pages[1];
|
|
int npages;
|
|
unsigned long hva, psize, offset;
|
|
unsigned long pa;
|
|
unsigned long *physp;
|
|
|
|
memslot = gfn_to_memslot(kvm, gfn);
|
|
if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
|
|
return NULL;
|
|
if (!kvm->arch.using_mmu_notifiers) {
|
|
physp = kvm->arch.slot_phys[memslot->id];
|
|
if (!physp)
|
|
return NULL;
|
|
physp += gfn - memslot->base_gfn;
|
|
pa = *physp;
|
|
if (!pa) {
|
|
if (kvmppc_get_guest_page(kvm, gfn, memslot,
|
|
PAGE_SIZE) < 0)
|
|
return NULL;
|
|
pa = *physp;
|
|
}
|
|
page = pfn_to_page(pa >> PAGE_SHIFT);
|
|
} else {
|
|
hva = gfn_to_hva_memslot(memslot, gfn);
|
|
npages = get_user_pages_fast(hva, 1, 1, pages);
|
|
if (npages < 1)
|
|
return NULL;
|
|
page = pages[0];
|
|
}
|
|
psize = PAGE_SIZE;
|
|
if (PageHuge(page)) {
|
|
page = compound_head(page);
|
|
psize <<= compound_order(page);
|
|
}
|
|
if (!kvm->arch.using_mmu_notifiers)
|
|
get_page(page);
|
|
offset = gpa & (psize - 1);
|
|
if (nb_ret)
|
|
*nb_ret = psize - offset;
|
|
return page_address(page) + offset;
|
|
}
|
|
|
|
void kvmppc_unpin_guest_page(struct kvm *kvm, void *va)
|
|
{
|
|
struct page *page = virt_to_page(va);
|
|
|
|
page = compound_head(page);
|
|
put_page(page);
|
|
}
|
|
|
|
void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
|
|
{
|
|
struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
|
|
|
|
if (cpu_has_feature(CPU_FTR_ARCH_206))
|
|
vcpu->arch.slb_nr = 32; /* POWER7 */
|
|
else
|
|
vcpu->arch.slb_nr = 64;
|
|
|
|
mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
|
|
mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
|
|
|
|
vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
|
|
}
|