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-----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAABAgAGBQJSiDFHAAoJEEtpOizt6ddyCWQH/jmTxPGBK3Bx1qTr25izgW8Z 69SYTfkRoCV/3O3VWh9LiOSz9zrnCm0ODopQmMUDbEYF8KnzMiLASZ5mf3xmvoo1 3KB/upM6DXEd2u2ZEQKnwp0cQZmcTzXM0PfGZ86xlmLFH6zjMt0iPa/FwflQMWsM QJyRJOMrB/WyLbY77FdsyK8RD4fJy7mlLS6LSXnnDb5gMeiPu8d9PWXdlIwCsEe3 Zk0AAyJBXYn0yjzrZ/5HbUlmTBMLbEIomzCqCVAglpiXUb7E0w7YoyTc3dagyMyK zZ+6OqJAZpIi5tliGuhadLsioinM/L9xfnOFtd8jtvPqZbYcetkphTbBg9Bj4mw= =VmDY -----END PGP SIGNATURE----- Merge tag 'kvm-arm-fixes-3.13-1' of git://git.linaro.org/people/cdall/linux-kvm-arm into next Fix percpu vmalloc allocations
1004 lines
26 KiB
C
1004 lines
26 KiB
C
/*
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* Copyright (C) 2012 - Virtual Open Systems and Columbia University
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* Author: Christoffer Dall <c.dall@virtualopensystems.com>
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*
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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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#include <linux/mman.h>
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#include <linux/kvm_host.h>
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#include <linux/io.h>
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#include <linux/hugetlb.h>
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#include <trace/events/kvm.h>
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#include <asm/pgalloc.h>
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#include <asm/cacheflush.h>
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#include <asm/kvm_arm.h>
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#include <asm/kvm_mmu.h>
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#include <asm/kvm_mmio.h>
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#include <asm/kvm_asm.h>
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#include <asm/kvm_emulate.h>
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#include "trace.h"
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extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
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static pgd_t *boot_hyp_pgd;
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static pgd_t *hyp_pgd;
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static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
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static void *init_bounce_page;
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static unsigned long hyp_idmap_start;
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static unsigned long hyp_idmap_end;
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static phys_addr_t hyp_idmap_vector;
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#define kvm_pmd_huge(_x) (pmd_huge(_x) || pmd_trans_huge(_x))
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static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
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{
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/*
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* This function also gets called when dealing with HYP page
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* tables. As HYP doesn't have an associated struct kvm (and
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* the HYP page tables are fairly static), we don't do
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* anything there.
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*/
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if (kvm)
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kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa);
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}
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static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
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int min, int max)
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{
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void *page;
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BUG_ON(max > KVM_NR_MEM_OBJS);
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if (cache->nobjs >= min)
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return 0;
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while (cache->nobjs < max) {
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page = (void *)__get_free_page(PGALLOC_GFP);
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if (!page)
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return -ENOMEM;
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cache->objects[cache->nobjs++] = page;
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}
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return 0;
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}
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static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
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{
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while (mc->nobjs)
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free_page((unsigned long)mc->objects[--mc->nobjs]);
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}
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static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
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{
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void *p;
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BUG_ON(!mc || !mc->nobjs);
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p = mc->objects[--mc->nobjs];
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return p;
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}
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static bool page_empty(void *ptr)
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{
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struct page *ptr_page = virt_to_page(ptr);
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return page_count(ptr_page) == 1;
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}
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static void clear_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr)
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{
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if (pud_huge(*pud)) {
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pud_clear(pud);
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kvm_tlb_flush_vmid_ipa(kvm, addr);
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} else {
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pmd_t *pmd_table = pmd_offset(pud, 0);
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pud_clear(pud);
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kvm_tlb_flush_vmid_ipa(kvm, addr);
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pmd_free(NULL, pmd_table);
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}
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put_page(virt_to_page(pud));
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}
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static void clear_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr)
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{
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if (kvm_pmd_huge(*pmd)) {
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pmd_clear(pmd);
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kvm_tlb_flush_vmid_ipa(kvm, addr);
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} else {
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pte_t *pte_table = pte_offset_kernel(pmd, 0);
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pmd_clear(pmd);
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kvm_tlb_flush_vmid_ipa(kvm, addr);
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pte_free_kernel(NULL, pte_table);
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}
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put_page(virt_to_page(pmd));
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}
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static void clear_pte_entry(struct kvm *kvm, pte_t *pte, phys_addr_t addr)
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{
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if (pte_present(*pte)) {
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kvm_set_pte(pte, __pte(0));
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put_page(virt_to_page(pte));
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kvm_tlb_flush_vmid_ipa(kvm, addr);
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}
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}
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static void unmap_range(struct kvm *kvm, pgd_t *pgdp,
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unsigned long long start, u64 size)
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{
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pgd_t *pgd;
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pud_t *pud;
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pmd_t *pmd;
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pte_t *pte;
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unsigned long long addr = start, end = start + size;
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u64 next;
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while (addr < end) {
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pgd = pgdp + pgd_index(addr);
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pud = pud_offset(pgd, addr);
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if (pud_none(*pud)) {
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addr = pud_addr_end(addr, end);
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continue;
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}
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if (pud_huge(*pud)) {
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/*
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* If we are dealing with a huge pud, just clear it and
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* move on.
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*/
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clear_pud_entry(kvm, pud, addr);
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addr = pud_addr_end(addr, end);
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continue;
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}
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pmd = pmd_offset(pud, addr);
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if (pmd_none(*pmd)) {
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addr = pmd_addr_end(addr, end);
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continue;
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}
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if (!kvm_pmd_huge(*pmd)) {
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pte = pte_offset_kernel(pmd, addr);
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clear_pte_entry(kvm, pte, addr);
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next = addr + PAGE_SIZE;
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}
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/*
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* If the pmd entry is to be cleared, walk back up the ladder
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*/
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if (kvm_pmd_huge(*pmd) || page_empty(pte)) {
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clear_pmd_entry(kvm, pmd, addr);
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next = pmd_addr_end(addr, end);
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if (page_empty(pmd) && !page_empty(pud)) {
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clear_pud_entry(kvm, pud, addr);
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next = pud_addr_end(addr, end);
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}
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}
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addr = next;
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}
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}
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/**
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* free_boot_hyp_pgd - free HYP boot page tables
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*
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* Free the HYP boot page tables. The bounce page is also freed.
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*/
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void free_boot_hyp_pgd(void)
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{
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mutex_lock(&kvm_hyp_pgd_mutex);
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if (boot_hyp_pgd) {
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unmap_range(NULL, boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE);
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unmap_range(NULL, boot_hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE);
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kfree(boot_hyp_pgd);
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boot_hyp_pgd = NULL;
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}
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if (hyp_pgd)
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unmap_range(NULL, hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE);
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kfree(init_bounce_page);
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init_bounce_page = NULL;
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mutex_unlock(&kvm_hyp_pgd_mutex);
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}
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/**
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* free_hyp_pgds - free Hyp-mode page tables
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*
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* Assumes hyp_pgd is a page table used strictly in Hyp-mode and
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* therefore contains either mappings in the kernel memory area (above
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* PAGE_OFFSET), or device mappings in the vmalloc range (from
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* VMALLOC_START to VMALLOC_END).
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*
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* boot_hyp_pgd should only map two pages for the init code.
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*/
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void free_hyp_pgds(void)
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{
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unsigned long addr;
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free_boot_hyp_pgd();
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mutex_lock(&kvm_hyp_pgd_mutex);
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if (hyp_pgd) {
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for (addr = PAGE_OFFSET; virt_addr_valid(addr); addr += PGDIR_SIZE)
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unmap_range(NULL, hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE);
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for (addr = VMALLOC_START; is_vmalloc_addr((void*)addr); addr += PGDIR_SIZE)
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unmap_range(NULL, hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE);
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kfree(hyp_pgd);
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hyp_pgd = NULL;
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}
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mutex_unlock(&kvm_hyp_pgd_mutex);
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}
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static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
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unsigned long end, unsigned long pfn,
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pgprot_t prot)
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{
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pte_t *pte;
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unsigned long addr;
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addr = start;
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do {
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pte = pte_offset_kernel(pmd, addr);
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kvm_set_pte(pte, pfn_pte(pfn, prot));
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get_page(virt_to_page(pte));
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kvm_flush_dcache_to_poc(pte, sizeof(*pte));
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pfn++;
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} while (addr += PAGE_SIZE, addr != end);
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}
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static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
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unsigned long end, unsigned long pfn,
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pgprot_t prot)
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{
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pmd_t *pmd;
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pte_t *pte;
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unsigned long addr, next;
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addr = start;
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do {
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pmd = pmd_offset(pud, addr);
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BUG_ON(pmd_sect(*pmd));
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if (pmd_none(*pmd)) {
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pte = pte_alloc_one_kernel(NULL, addr);
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if (!pte) {
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kvm_err("Cannot allocate Hyp pte\n");
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return -ENOMEM;
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}
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pmd_populate_kernel(NULL, pmd, pte);
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get_page(virt_to_page(pmd));
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kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
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}
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next = pmd_addr_end(addr, end);
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create_hyp_pte_mappings(pmd, addr, next, pfn, prot);
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pfn += (next - addr) >> PAGE_SHIFT;
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} while (addr = next, addr != end);
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return 0;
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}
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static int __create_hyp_mappings(pgd_t *pgdp,
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unsigned long start, unsigned long end,
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unsigned long pfn, pgprot_t prot)
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{
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pgd_t *pgd;
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pud_t *pud;
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pmd_t *pmd;
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unsigned long addr, next;
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int err = 0;
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mutex_lock(&kvm_hyp_pgd_mutex);
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addr = start & PAGE_MASK;
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end = PAGE_ALIGN(end);
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do {
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pgd = pgdp + pgd_index(addr);
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pud = pud_offset(pgd, addr);
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if (pud_none_or_clear_bad(pud)) {
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pmd = pmd_alloc_one(NULL, addr);
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if (!pmd) {
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kvm_err("Cannot allocate Hyp pmd\n");
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err = -ENOMEM;
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goto out;
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}
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pud_populate(NULL, pud, pmd);
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get_page(virt_to_page(pud));
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kvm_flush_dcache_to_poc(pud, sizeof(*pud));
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}
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next = pgd_addr_end(addr, end);
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err = create_hyp_pmd_mappings(pud, addr, next, pfn, prot);
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if (err)
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goto out;
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pfn += (next - addr) >> PAGE_SHIFT;
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} while (addr = next, addr != end);
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out:
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mutex_unlock(&kvm_hyp_pgd_mutex);
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return err;
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}
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static phys_addr_t kvm_kaddr_to_phys(void *kaddr)
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{
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if (!is_vmalloc_addr(kaddr)) {
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BUG_ON(!virt_addr_valid(kaddr));
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return __pa(kaddr);
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} else {
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return page_to_phys(vmalloc_to_page(kaddr)) +
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offset_in_page(kaddr);
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}
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}
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/**
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* create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode
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* @from: The virtual kernel start address of the range
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* @to: The virtual kernel end address of the range (exclusive)
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*
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* The same virtual address as the kernel virtual address is also used
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* in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) to the same underlying
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* physical pages.
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*/
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int create_hyp_mappings(void *from, void *to)
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{
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phys_addr_t phys_addr;
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unsigned long virt_addr;
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unsigned long start = KERN_TO_HYP((unsigned long)from);
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unsigned long end = KERN_TO_HYP((unsigned long)to);
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start = start & PAGE_MASK;
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end = PAGE_ALIGN(end);
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for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) {
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int err;
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phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
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err = __create_hyp_mappings(hyp_pgd, virt_addr,
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virt_addr + PAGE_SIZE,
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__phys_to_pfn(phys_addr),
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PAGE_HYP);
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if (err)
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return err;
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}
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return 0;
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}
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/**
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* create_hyp_io_mappings - duplicate a kernel IO mapping into Hyp mode
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* @from: The kernel start VA of the range
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* @to: The kernel end VA of the range (exclusive)
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* @phys_addr: The physical start address which gets mapped
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*
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* The resulting HYP VA is the same as the kernel VA, modulo
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* HYP_PAGE_OFFSET.
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*/
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int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_addr)
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{
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unsigned long start = KERN_TO_HYP((unsigned long)from);
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unsigned long end = KERN_TO_HYP((unsigned long)to);
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/* Check for a valid kernel IO mapping */
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if (!is_vmalloc_addr(from) || !is_vmalloc_addr(to - 1))
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return -EINVAL;
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return __create_hyp_mappings(hyp_pgd, start, end,
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__phys_to_pfn(phys_addr), PAGE_HYP_DEVICE);
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}
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/**
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* kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
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* @kvm: The KVM struct pointer for the VM.
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*
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* Allocates the 1st level table only of size defined by S2_PGD_ORDER (can
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* support either full 40-bit input addresses or limited to 32-bit input
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* addresses). Clears the allocated pages.
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*
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* Note we don't need locking here as this is only called when the VM is
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* created, which can only be done once.
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*/
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int kvm_alloc_stage2_pgd(struct kvm *kvm)
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{
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pgd_t *pgd;
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if (kvm->arch.pgd != NULL) {
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kvm_err("kvm_arch already initialized?\n");
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return -EINVAL;
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}
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pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, S2_PGD_ORDER);
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if (!pgd)
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return -ENOMEM;
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memset(pgd, 0, PTRS_PER_S2_PGD * sizeof(pgd_t));
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kvm_clean_pgd(pgd);
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kvm->arch.pgd = pgd;
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return 0;
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}
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/**
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* unmap_stage2_range -- Clear stage2 page table entries to unmap a range
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* @kvm: The VM pointer
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* @start: The intermediate physical base address of the range to unmap
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* @size: The size of the area to unmap
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*
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* Clear a range of stage-2 mappings, lowering the various ref-counts. Must
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* be called while holding mmu_lock (unless for freeing the stage2 pgd before
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* destroying the VM), otherwise another faulting VCPU may come in and mess
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* with things behind our backs.
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*/
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static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
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{
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unmap_range(kvm, kvm->arch.pgd, start, size);
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}
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/**
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* kvm_free_stage2_pgd - free all stage-2 tables
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* @kvm: The KVM struct pointer for the VM.
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*
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* Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
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* underlying level-2 and level-3 tables before freeing the actual level-1 table
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* and setting the struct pointer to NULL.
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*
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* Note we don't need locking here as this is only called when the VM is
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* destroyed, which can only be done once.
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*/
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void kvm_free_stage2_pgd(struct kvm *kvm)
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{
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if (kvm->arch.pgd == NULL)
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return;
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unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
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free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER);
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kvm->arch.pgd = NULL;
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}
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static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
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phys_addr_t addr)
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{
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pgd_t *pgd;
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|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
|
|
pgd = kvm->arch.pgd + pgd_index(addr);
|
|
pud = pud_offset(pgd, addr);
|
|
if (pud_none(*pud)) {
|
|
if (!cache)
|
|
return NULL;
|
|
pmd = mmu_memory_cache_alloc(cache);
|
|
pud_populate(NULL, pud, pmd);
|
|
get_page(virt_to_page(pud));
|
|
}
|
|
|
|
return pmd_offset(pud, addr);
|
|
}
|
|
|
|
static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
|
|
*cache, phys_addr_t addr, const pmd_t *new_pmd)
|
|
{
|
|
pmd_t *pmd, old_pmd;
|
|
|
|
pmd = stage2_get_pmd(kvm, cache, addr);
|
|
VM_BUG_ON(!pmd);
|
|
|
|
/*
|
|
* Mapping in huge pages should only happen through a fault. If a
|
|
* page is merged into a transparent huge page, the individual
|
|
* subpages of that huge page should be unmapped through MMU
|
|
* notifiers before we get here.
|
|
*
|
|
* Merging of CompoundPages is not supported; they should become
|
|
* splitting first, unmapped, merged, and mapped back in on-demand.
|
|
*/
|
|
VM_BUG_ON(pmd_present(*pmd) && pmd_pfn(*pmd) != pmd_pfn(*new_pmd));
|
|
|
|
old_pmd = *pmd;
|
|
kvm_set_pmd(pmd, *new_pmd);
|
|
if (pmd_present(old_pmd))
|
|
kvm_tlb_flush_vmid_ipa(kvm, addr);
|
|
else
|
|
get_page(virt_to_page(pmd));
|
|
return 0;
|
|
}
|
|
|
|
static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
|
|
phys_addr_t addr, const pte_t *new_pte, bool iomap)
|
|
{
|
|
pmd_t *pmd;
|
|
pte_t *pte, old_pte;
|
|
|
|
/* Create stage-2 page table mapping - Level 1 */
|
|
pmd = stage2_get_pmd(kvm, cache, addr);
|
|
if (!pmd) {
|
|
/*
|
|
* Ignore calls from kvm_set_spte_hva for unallocated
|
|
* address ranges.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
/* Create stage-2 page mappings - Level 2 */
|
|
if (pmd_none(*pmd)) {
|
|
if (!cache)
|
|
return 0; /* ignore calls from kvm_set_spte_hva */
|
|
pte = mmu_memory_cache_alloc(cache);
|
|
kvm_clean_pte(pte);
|
|
pmd_populate_kernel(NULL, pmd, pte);
|
|
get_page(virt_to_page(pmd));
|
|
}
|
|
|
|
pte = pte_offset_kernel(pmd, addr);
|
|
|
|
if (iomap && pte_present(*pte))
|
|
return -EFAULT;
|
|
|
|
/* Create 2nd stage page table mapping - Level 3 */
|
|
old_pte = *pte;
|
|
kvm_set_pte(pte, *new_pte);
|
|
if (pte_present(old_pte))
|
|
kvm_tlb_flush_vmid_ipa(kvm, addr);
|
|
else
|
|
get_page(virt_to_page(pte));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* kvm_phys_addr_ioremap - map a device range to guest IPA
|
|
*
|
|
* @kvm: The KVM pointer
|
|
* @guest_ipa: The IPA at which to insert the mapping
|
|
* @pa: The physical address of the device
|
|
* @size: The size of the mapping
|
|
*/
|
|
int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
|
|
phys_addr_t pa, unsigned long size)
|
|
{
|
|
phys_addr_t addr, end;
|
|
int ret = 0;
|
|
unsigned long pfn;
|
|
struct kvm_mmu_memory_cache cache = { 0, };
|
|
|
|
end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
|
|
pfn = __phys_to_pfn(pa);
|
|
|
|
for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
|
|
pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE);
|
|
|
|
ret = mmu_topup_memory_cache(&cache, 2, 2);
|
|
if (ret)
|
|
goto out;
|
|
spin_lock(&kvm->mmu_lock);
|
|
ret = stage2_set_pte(kvm, &cache, addr, &pte, true);
|
|
spin_unlock(&kvm->mmu_lock);
|
|
if (ret)
|
|
goto out;
|
|
|
|
pfn++;
|
|
}
|
|
|
|
out:
|
|
mmu_free_memory_cache(&cache);
|
|
return ret;
|
|
}
|
|
|
|
static bool transparent_hugepage_adjust(pfn_t *pfnp, phys_addr_t *ipap)
|
|
{
|
|
pfn_t pfn = *pfnp;
|
|
gfn_t gfn = *ipap >> PAGE_SHIFT;
|
|
|
|
if (PageTransCompound(pfn_to_page(pfn))) {
|
|
unsigned long mask;
|
|
/*
|
|
* The address we faulted on is backed by a transparent huge
|
|
* page. However, because we map the compound huge page and
|
|
* not the individual tail page, we need to transfer the
|
|
* refcount to the head page. We have to be careful that the
|
|
* THP doesn't start to split while we are adjusting the
|
|
* refcounts.
|
|
*
|
|
* We are sure this doesn't happen, because mmu_notifier_retry
|
|
* was successful and we are holding the mmu_lock, so if this
|
|
* THP is trying to split, it will be blocked in the mmu
|
|
* notifier before touching any of the pages, specifically
|
|
* before being able to call __split_huge_page_refcount().
|
|
*
|
|
* We can therefore safely transfer the refcount from PG_tail
|
|
* to PG_head and switch the pfn from a tail page to the head
|
|
* page accordingly.
|
|
*/
|
|
mask = PTRS_PER_PMD - 1;
|
|
VM_BUG_ON((gfn & mask) != (pfn & mask));
|
|
if (pfn & mask) {
|
|
*ipap &= PMD_MASK;
|
|
kvm_release_pfn_clean(pfn);
|
|
pfn &= ~mask;
|
|
kvm_get_pfn(pfn);
|
|
*pfnp = pfn;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
|
|
struct kvm_memory_slot *memslot,
|
|
unsigned long fault_status)
|
|
{
|
|
int ret;
|
|
bool write_fault, writable, hugetlb = false, force_pte = false;
|
|
unsigned long mmu_seq;
|
|
gfn_t gfn = fault_ipa >> PAGE_SHIFT;
|
|
unsigned long hva = gfn_to_hva(vcpu->kvm, gfn);
|
|
struct kvm *kvm = vcpu->kvm;
|
|
struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
|
|
struct vm_area_struct *vma;
|
|
pfn_t pfn;
|
|
|
|
write_fault = kvm_is_write_fault(kvm_vcpu_get_hsr(vcpu));
|
|
if (fault_status == FSC_PERM && !write_fault) {
|
|
kvm_err("Unexpected L2 read permission error\n");
|
|
return -EFAULT;
|
|
}
|
|
|
|
/* Let's check if we will get back a huge page backed by hugetlbfs */
|
|
down_read(¤t->mm->mmap_sem);
|
|
vma = find_vma_intersection(current->mm, hva, hva + 1);
|
|
if (is_vm_hugetlb_page(vma)) {
|
|
hugetlb = true;
|
|
gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT;
|
|
} else {
|
|
/*
|
|
* Pages belonging to VMAs not aligned to the PMD mapping
|
|
* granularity cannot be mapped using block descriptors even
|
|
* if the pages belong to a THP for the process, because the
|
|
* stage-2 block descriptor will cover more than a single THP
|
|
* and we loose atomicity for unmapping, updates, and splits
|
|
* of the THP or other pages in the stage-2 block range.
|
|
*/
|
|
if (vma->vm_start & ~PMD_MASK)
|
|
force_pte = true;
|
|
}
|
|
up_read(¤t->mm->mmap_sem);
|
|
|
|
/* We need minimum second+third level pages */
|
|
ret = mmu_topup_memory_cache(memcache, 2, KVM_NR_MEM_OBJS);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mmu_seq = vcpu->kvm->mmu_notifier_seq;
|
|
/*
|
|
* Ensure the read of mmu_notifier_seq happens before we call
|
|
* gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk
|
|
* the page we just got a reference to gets unmapped before we have a
|
|
* chance to grab the mmu_lock, which ensure that if the page gets
|
|
* unmapped afterwards, the call to kvm_unmap_hva will take it away
|
|
* from us again properly. This smp_rmb() interacts with the smp_wmb()
|
|
* in kvm_mmu_notifier_invalidate_<page|range_end>.
|
|
*/
|
|
smp_rmb();
|
|
|
|
pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writable);
|
|
if (is_error_pfn(pfn))
|
|
return -EFAULT;
|
|
|
|
spin_lock(&kvm->mmu_lock);
|
|
if (mmu_notifier_retry(kvm, mmu_seq))
|
|
goto out_unlock;
|
|
if (!hugetlb && !force_pte)
|
|
hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa);
|
|
|
|
if (hugetlb) {
|
|
pmd_t new_pmd = pfn_pmd(pfn, PAGE_S2);
|
|
new_pmd = pmd_mkhuge(new_pmd);
|
|
if (writable) {
|
|
kvm_set_s2pmd_writable(&new_pmd);
|
|
kvm_set_pfn_dirty(pfn);
|
|
}
|
|
coherent_icache_guest_page(kvm, hva & PMD_MASK, PMD_SIZE);
|
|
ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
|
|
} else {
|
|
pte_t new_pte = pfn_pte(pfn, PAGE_S2);
|
|
if (writable) {
|
|
kvm_set_s2pte_writable(&new_pte);
|
|
kvm_set_pfn_dirty(pfn);
|
|
}
|
|
coherent_icache_guest_page(kvm, hva, PAGE_SIZE);
|
|
ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, false);
|
|
}
|
|
|
|
|
|
out_unlock:
|
|
spin_unlock(&kvm->mmu_lock);
|
|
kvm_release_pfn_clean(pfn);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* kvm_handle_guest_abort - handles all 2nd stage aborts
|
|
* @vcpu: the VCPU pointer
|
|
* @run: the kvm_run structure
|
|
*
|
|
* Any abort that gets to the host is almost guaranteed to be caused by a
|
|
* missing second stage translation table entry, which can mean that either the
|
|
* guest simply needs more memory and we must allocate an appropriate page or it
|
|
* can mean that the guest tried to access I/O memory, which is emulated by user
|
|
* space. The distinction is based on the IPA causing the fault and whether this
|
|
* memory region has been registered as standard RAM by user space.
|
|
*/
|
|
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
|
|
{
|
|
unsigned long fault_status;
|
|
phys_addr_t fault_ipa;
|
|
struct kvm_memory_slot *memslot;
|
|
bool is_iabt;
|
|
gfn_t gfn;
|
|
int ret, idx;
|
|
|
|
is_iabt = kvm_vcpu_trap_is_iabt(vcpu);
|
|
fault_ipa = kvm_vcpu_get_fault_ipa(vcpu);
|
|
|
|
trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_hsr(vcpu),
|
|
kvm_vcpu_get_hfar(vcpu), fault_ipa);
|
|
|
|
/* Check the stage-2 fault is trans. fault or write fault */
|
|
fault_status = kvm_vcpu_trap_get_fault(vcpu);
|
|
if (fault_status != FSC_FAULT && fault_status != FSC_PERM) {
|
|
kvm_err("Unsupported fault status: EC=%#x DFCS=%#lx\n",
|
|
kvm_vcpu_trap_get_class(vcpu), fault_status);
|
|
return -EFAULT;
|
|
}
|
|
|
|
idx = srcu_read_lock(&vcpu->kvm->srcu);
|
|
|
|
gfn = fault_ipa >> PAGE_SHIFT;
|
|
if (!kvm_is_visible_gfn(vcpu->kvm, gfn)) {
|
|
if (is_iabt) {
|
|
/* Prefetch Abort on I/O address */
|
|
kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu));
|
|
ret = 1;
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (fault_status != FSC_FAULT) {
|
|
kvm_err("Unsupported fault status on io memory: %#lx\n",
|
|
fault_status);
|
|
ret = -EFAULT;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/*
|
|
* The IPA is reported as [MAX:12], so we need to
|
|
* complement it with the bottom 12 bits from the
|
|
* faulting VA. This is always 12 bits, irrespective
|
|
* of the page size.
|
|
*/
|
|
fault_ipa |= kvm_vcpu_get_hfar(vcpu) & ((1 << 12) - 1);
|
|
ret = io_mem_abort(vcpu, run, fault_ipa);
|
|
goto out_unlock;
|
|
}
|
|
|
|
memslot = gfn_to_memslot(vcpu->kvm, gfn);
|
|
|
|
ret = user_mem_abort(vcpu, fault_ipa, memslot, fault_status);
|
|
if (ret == 0)
|
|
ret = 1;
|
|
out_unlock:
|
|
srcu_read_unlock(&vcpu->kvm->srcu, idx);
|
|
return ret;
|
|
}
|
|
|
|
static void handle_hva_to_gpa(struct kvm *kvm,
|
|
unsigned long start,
|
|
unsigned long end,
|
|
void (*handler)(struct kvm *kvm,
|
|
gpa_t gpa, void *data),
|
|
void *data)
|
|
{
|
|
struct kvm_memslots *slots;
|
|
struct kvm_memory_slot *memslot;
|
|
|
|
slots = kvm_memslots(kvm);
|
|
|
|
/* we only care about the pages that the guest sees */
|
|
kvm_for_each_memslot(memslot, slots) {
|
|
unsigned long hva_start, hva_end;
|
|
gfn_t gfn, gfn_end;
|
|
|
|
hva_start = max(start, memslot->userspace_addr);
|
|
hva_end = min(end, memslot->userspace_addr +
|
|
(memslot->npages << PAGE_SHIFT));
|
|
if (hva_start >= hva_end)
|
|
continue;
|
|
|
|
/*
|
|
* {gfn(page) | page intersects with [hva_start, hva_end)} =
|
|
* {gfn_start, gfn_start+1, ..., gfn_end-1}.
|
|
*/
|
|
gfn = hva_to_gfn_memslot(hva_start, memslot);
|
|
gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
|
|
|
|
for (; gfn < gfn_end; ++gfn) {
|
|
gpa_t gpa = gfn << PAGE_SHIFT;
|
|
handler(kvm, gpa, data);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
|
|
{
|
|
unmap_stage2_range(kvm, gpa, PAGE_SIZE);
|
|
}
|
|
|
|
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
|
|
{
|
|
unsigned long end = hva + PAGE_SIZE;
|
|
|
|
if (!kvm->arch.pgd)
|
|
return 0;
|
|
|
|
trace_kvm_unmap_hva(hva);
|
|
handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL);
|
|
return 0;
|
|
}
|
|
|
|
int kvm_unmap_hva_range(struct kvm *kvm,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
if (!kvm->arch.pgd)
|
|
return 0;
|
|
|
|
trace_kvm_unmap_hva_range(start, end);
|
|
handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
|
|
return 0;
|
|
}
|
|
|
|
static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data)
|
|
{
|
|
pte_t *pte = (pte_t *)data;
|
|
|
|
stage2_set_pte(kvm, NULL, gpa, pte, false);
|
|
}
|
|
|
|
|
|
void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
|
|
{
|
|
unsigned long end = hva + PAGE_SIZE;
|
|
pte_t stage2_pte;
|
|
|
|
if (!kvm->arch.pgd)
|
|
return;
|
|
|
|
trace_kvm_set_spte_hva(hva);
|
|
stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
|
|
handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
|
|
}
|
|
|
|
void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
|
|
{
|
|
mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
|
|
}
|
|
|
|
phys_addr_t kvm_mmu_get_httbr(void)
|
|
{
|
|
return virt_to_phys(hyp_pgd);
|
|
}
|
|
|
|
phys_addr_t kvm_mmu_get_boot_httbr(void)
|
|
{
|
|
return virt_to_phys(boot_hyp_pgd);
|
|
}
|
|
|
|
phys_addr_t kvm_get_idmap_vector(void)
|
|
{
|
|
return hyp_idmap_vector;
|
|
}
|
|
|
|
int kvm_mmu_init(void)
|
|
{
|
|
int err;
|
|
|
|
hyp_idmap_start = virt_to_phys(__hyp_idmap_text_start);
|
|
hyp_idmap_end = virt_to_phys(__hyp_idmap_text_end);
|
|
hyp_idmap_vector = virt_to_phys(__kvm_hyp_init);
|
|
|
|
if ((hyp_idmap_start ^ hyp_idmap_end) & PAGE_MASK) {
|
|
/*
|
|
* Our init code is crossing a page boundary. Allocate
|
|
* a bounce page, copy the code over and use that.
|
|
*/
|
|
size_t len = __hyp_idmap_text_end - __hyp_idmap_text_start;
|
|
phys_addr_t phys_base;
|
|
|
|
init_bounce_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
|
if (!init_bounce_page) {
|
|
kvm_err("Couldn't allocate HYP init bounce page\n");
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
memcpy(init_bounce_page, __hyp_idmap_text_start, len);
|
|
/*
|
|
* Warning: the code we just copied to the bounce page
|
|
* must be flushed to the point of coherency.
|
|
* Otherwise, the data may be sitting in L2, and HYP
|
|
* mode won't be able to observe it as it runs with
|
|
* caches off at that point.
|
|
*/
|
|
kvm_flush_dcache_to_poc(init_bounce_page, len);
|
|
|
|
phys_base = virt_to_phys(init_bounce_page);
|
|
hyp_idmap_vector += phys_base - hyp_idmap_start;
|
|
hyp_idmap_start = phys_base;
|
|
hyp_idmap_end = phys_base + len;
|
|
|
|
kvm_info("Using HYP init bounce page @%lx\n",
|
|
(unsigned long)phys_base);
|
|
}
|
|
|
|
hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL);
|
|
boot_hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL);
|
|
if (!hyp_pgd || !boot_hyp_pgd) {
|
|
kvm_err("Hyp mode PGD not allocated\n");
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
/* Create the idmap in the boot page tables */
|
|
err = __create_hyp_mappings(boot_hyp_pgd,
|
|
hyp_idmap_start, hyp_idmap_end,
|
|
__phys_to_pfn(hyp_idmap_start),
|
|
PAGE_HYP);
|
|
|
|
if (err) {
|
|
kvm_err("Failed to idmap %lx-%lx\n",
|
|
hyp_idmap_start, hyp_idmap_end);
|
|
goto out;
|
|
}
|
|
|
|
/* Map the very same page at the trampoline VA */
|
|
err = __create_hyp_mappings(boot_hyp_pgd,
|
|
TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE,
|
|
__phys_to_pfn(hyp_idmap_start),
|
|
PAGE_HYP);
|
|
if (err) {
|
|
kvm_err("Failed to map trampoline @%lx into boot HYP pgd\n",
|
|
TRAMPOLINE_VA);
|
|
goto out;
|
|
}
|
|
|
|
/* Map the same page again into the runtime page tables */
|
|
err = __create_hyp_mappings(hyp_pgd,
|
|
TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE,
|
|
__phys_to_pfn(hyp_idmap_start),
|
|
PAGE_HYP);
|
|
if (err) {
|
|
kvm_err("Failed to map trampoline @%lx into runtime HYP pgd\n",
|
|
TRAMPOLINE_VA);
|
|
goto out;
|
|
}
|
|
|
|
return 0;
|
|
out:
|
|
free_hyp_pgds();
|
|
return err;
|
|
}
|