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authorAvi Kivity <avi@qumranet.com>2007-12-16 10:02:48 +0100
committerAvi Kivity <avi@qumranet.com>2008-01-30 17:01:18 +0100
commitedf884172e9828c6234b254208af04655855038d (patch)
treef5e5d1eecaed9737eced6ba60d09fe93149751c1 /drivers/kvm/mmu.c
parentKVM: VMX: Add printk_ratelimit in vmx_intr_assist (diff)
downloadlinux-edf884172e9828c6234b254208af04655855038d.tar.xz
linux-edf884172e9828c6234b254208af04655855038d.zip
KVM: Move arch dependent files to new directory arch/x86/kvm/
This paves the way for multiple architecture support. Note that while ioapic.c could potentially be shared with ia64, it is also moved. Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'drivers/kvm/mmu.c')
-rw-r--r--drivers/kvm/mmu.c1806
1 files changed, 0 insertions, 1806 deletions
diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c
deleted file mode 100644
index c26d83f86a3a..000000000000
--- a/drivers/kvm/mmu.c
+++ /dev/null
@@ -1,1806 +0,0 @@
-/*
- * Kernel-based Virtual Machine driver for Linux
- *
- * This module enables machines with Intel VT-x extensions to run virtual
- * machines without emulation or binary translation.
- *
- * MMU support
- *
- * Copyright (C) 2006 Qumranet, Inc.
- *
- * Authors:
- * Yaniv Kamay <yaniv@qumranet.com>
- * Avi Kivity <avi@qumranet.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- */
-
-#include "vmx.h"
-#include "kvm.h"
-#include "x86.h"
-#include "mmu.h"
-
-#include <linux/types.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/highmem.h>
-#include <linux/module.h>
-#include <linux/swap.h>
-
-#include <asm/page.h>
-#include <asm/cmpxchg.h>
-#include <asm/io.h>
-
-#undef MMU_DEBUG
-
-#undef AUDIT
-
-#ifdef AUDIT
-static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg);
-#else
-static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {}
-#endif
-
-#ifdef MMU_DEBUG
-
-#define pgprintk(x...) do { if (dbg) printk(x); } while (0)
-#define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
-
-#else
-
-#define pgprintk(x...) do { } while (0)
-#define rmap_printk(x...) do { } while (0)
-
-#endif
-
-#if defined(MMU_DEBUG) || defined(AUDIT)
-static int dbg = 1;
-#endif
-
-#ifndef MMU_DEBUG
-#define ASSERT(x) do { } while (0)
-#else
-#define ASSERT(x) \
- if (!(x)) { \
- printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
- __FILE__, __LINE__, #x); \
- }
-#endif
-
-#define PT64_PT_BITS 9
-#define PT64_ENT_PER_PAGE (1 << PT64_PT_BITS)
-#define PT32_PT_BITS 10
-#define PT32_ENT_PER_PAGE (1 << PT32_PT_BITS)
-
-#define PT_WRITABLE_SHIFT 1
-
-#define PT_PRESENT_MASK (1ULL << 0)
-#define PT_WRITABLE_MASK (1ULL << PT_WRITABLE_SHIFT)
-#define PT_USER_MASK (1ULL << 2)
-#define PT_PWT_MASK (1ULL << 3)
-#define PT_PCD_MASK (1ULL << 4)
-#define PT_ACCESSED_MASK (1ULL << 5)
-#define PT_DIRTY_MASK (1ULL << 6)
-#define PT_PAGE_SIZE_MASK (1ULL << 7)
-#define PT_PAT_MASK (1ULL << 7)
-#define PT_GLOBAL_MASK (1ULL << 8)
-#define PT64_NX_SHIFT 63
-#define PT64_NX_MASK (1ULL << PT64_NX_SHIFT)
-
-#define PT_PAT_SHIFT 7
-#define PT_DIR_PAT_SHIFT 12
-#define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT)
-
-#define PT32_DIR_PSE36_SIZE 4
-#define PT32_DIR_PSE36_SHIFT 13
-#define PT32_DIR_PSE36_MASK \
- (((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT)
-
-
-#define PT_FIRST_AVAIL_BITS_SHIFT 9
-#define PT64_SECOND_AVAIL_BITS_SHIFT 52
-
-#define PT_SHADOW_IO_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT)
-
-#define VALID_PAGE(x) ((x) != INVALID_PAGE)
-
-#define PT64_LEVEL_BITS 9
-
-#define PT64_LEVEL_SHIFT(level) \
- (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
-
-#define PT64_LEVEL_MASK(level) \
- (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
-
-#define PT64_INDEX(address, level)\
- (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
-
-
-#define PT32_LEVEL_BITS 10
-
-#define PT32_LEVEL_SHIFT(level) \
- (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
-
-#define PT32_LEVEL_MASK(level) \
- (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
-
-#define PT32_INDEX(address, level)\
- (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
-
-
-#define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
-#define PT64_DIR_BASE_ADDR_MASK \
- (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
-
-#define PT32_BASE_ADDR_MASK PAGE_MASK
-#define PT32_DIR_BASE_ADDR_MASK \
- (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
-
-#define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
- | PT64_NX_MASK)
-
-#define PFERR_PRESENT_MASK (1U << 0)
-#define PFERR_WRITE_MASK (1U << 1)
-#define PFERR_USER_MASK (1U << 2)
-#define PFERR_FETCH_MASK (1U << 4)
-
-#define PT64_ROOT_LEVEL 4
-#define PT32_ROOT_LEVEL 2
-#define PT32E_ROOT_LEVEL 3
-
-#define PT_DIRECTORY_LEVEL 2
-#define PT_PAGE_TABLE_LEVEL 1
-
-#define RMAP_EXT 4
-
-#define ACC_EXEC_MASK 1
-#define ACC_WRITE_MASK PT_WRITABLE_MASK
-#define ACC_USER_MASK PT_USER_MASK
-#define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
-
-struct kvm_rmap_desc {
- u64 *shadow_ptes[RMAP_EXT];
- struct kvm_rmap_desc *more;
-};
-
-static struct kmem_cache *pte_chain_cache;
-static struct kmem_cache *rmap_desc_cache;
-static struct kmem_cache *mmu_page_header_cache;
-
-static u64 __read_mostly shadow_trap_nonpresent_pte;
-static u64 __read_mostly shadow_notrap_nonpresent_pte;
-
-void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte)
-{
- shadow_trap_nonpresent_pte = trap_pte;
- shadow_notrap_nonpresent_pte = notrap_pte;
-}
-EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes);
-
-static int is_write_protection(struct kvm_vcpu *vcpu)
-{
- return vcpu->arch.cr0 & X86_CR0_WP;
-}
-
-static int is_cpuid_PSE36(void)
-{
- return 1;
-}
-
-static int is_nx(struct kvm_vcpu *vcpu)
-{
- return vcpu->arch.shadow_efer & EFER_NX;
-}
-
-static int is_present_pte(unsigned long pte)
-{
- return pte & PT_PRESENT_MASK;
-}
-
-static int is_shadow_present_pte(u64 pte)
-{
- pte &= ~PT_SHADOW_IO_MARK;
- return pte != shadow_trap_nonpresent_pte
- && pte != shadow_notrap_nonpresent_pte;
-}
-
-static int is_writeble_pte(unsigned long pte)
-{
- return pte & PT_WRITABLE_MASK;
-}
-
-static int is_dirty_pte(unsigned long pte)
-{
- return pte & PT_DIRTY_MASK;
-}
-
-static int is_io_pte(unsigned long pte)
-{
- return pte & PT_SHADOW_IO_MARK;
-}
-
-static int is_rmap_pte(u64 pte)
-{
- return pte != shadow_trap_nonpresent_pte
- && pte != shadow_notrap_nonpresent_pte;
-}
-
-static gfn_t pse36_gfn_delta(u32 gpte)
-{
- int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT;
-
- return (gpte & PT32_DIR_PSE36_MASK) << shift;
-}
-
-static void set_shadow_pte(u64 *sptep, u64 spte)
-{
-#ifdef CONFIG_X86_64
- set_64bit((unsigned long *)sptep, spte);
-#else
- set_64bit((unsigned long long *)sptep, spte);
-#endif
-}
-
-static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
- struct kmem_cache *base_cache, int min)
-{
- void *obj;
-
- if (cache->nobjs >= min)
- return 0;
- while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
- obj = kmem_cache_zalloc(base_cache, GFP_KERNEL);
- if (!obj)
- return -ENOMEM;
- cache->objects[cache->nobjs++] = obj;
- }
- return 0;
-}
-
-static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
-{
- while (mc->nobjs)
- kfree(mc->objects[--mc->nobjs]);
-}
-
-static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
- int min)
-{
- struct page *page;
-
- if (cache->nobjs >= min)
- return 0;
- while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
- page = alloc_page(GFP_KERNEL);
- if (!page)
- return -ENOMEM;
- set_page_private(page, 0);
- cache->objects[cache->nobjs++] = page_address(page);
- }
- return 0;
-}
-
-static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache *mc)
-{
- while (mc->nobjs)
- free_page((unsigned long)mc->objects[--mc->nobjs]);
-}
-
-static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
-{
- int r;
-
- kvm_mmu_free_some_pages(vcpu);
- r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_chain_cache,
- pte_chain_cache, 4);
- if (r)
- goto out;
- r = mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache,
- rmap_desc_cache, 1);
- if (r)
- goto out;
- r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8);
- if (r)
- goto out;
- r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache,
- mmu_page_header_cache, 4);
-out:
- return r;
-}
-
-static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
-{
- mmu_free_memory_cache(&vcpu->arch.mmu_pte_chain_cache);
- mmu_free_memory_cache(&vcpu->arch.mmu_rmap_desc_cache);
- mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache);
- mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache);
-}
-
-static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc,
- size_t size)
-{
- void *p;
-
- BUG_ON(!mc->nobjs);
- p = mc->objects[--mc->nobjs];
- memset(p, 0, size);
- return p;
-}
-
-static struct kvm_pte_chain *mmu_alloc_pte_chain(struct kvm_vcpu *vcpu)
-{
- return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_chain_cache,
- sizeof(struct kvm_pte_chain));
-}
-
-static void mmu_free_pte_chain(struct kvm_pte_chain *pc)
-{
- kfree(pc);
-}
-
-static struct kvm_rmap_desc *mmu_alloc_rmap_desc(struct kvm_vcpu *vcpu)
-{
- return mmu_memory_cache_alloc(&vcpu->arch.mmu_rmap_desc_cache,
- sizeof(struct kvm_rmap_desc));
-}
-
-static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd)
-{
- kfree(rd);
-}
-
-/*
- * Take gfn and return the reverse mapping to it.
- * Note: gfn must be unaliased before this function get called
- */
-
-static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn)
-{
- struct kvm_memory_slot *slot;
-
- slot = gfn_to_memslot(kvm, gfn);
- return &slot->rmap[gfn - slot->base_gfn];
-}
-
-/*
- * Reverse mapping data structures:
- *
- * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
- * that points to page_address(page).
- *
- * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
- * containing more mappings.
- */
-static void rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
-{
- struct kvm_mmu_page *sp;
- struct kvm_rmap_desc *desc;
- unsigned long *rmapp;
- int i;
-
- if (!is_rmap_pte(*spte))
- return;
- gfn = unalias_gfn(vcpu->kvm, gfn);
- sp = page_header(__pa(spte));
- sp->gfns[spte - sp->spt] = gfn;
- rmapp = gfn_to_rmap(vcpu->kvm, gfn);
- if (!*rmapp) {
- rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte);
- *rmapp = (unsigned long)spte;
- } else if (!(*rmapp & 1)) {
- rmap_printk("rmap_add: %p %llx 1->many\n", spte, *spte);
- desc = mmu_alloc_rmap_desc(vcpu);
- desc->shadow_ptes[0] = (u64 *)*rmapp;
- desc->shadow_ptes[1] = spte;
- *rmapp = (unsigned long)desc | 1;
- } else {
- rmap_printk("rmap_add: %p %llx many->many\n", spte, *spte);
- desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
- while (desc->shadow_ptes[RMAP_EXT-1] && desc->more)
- desc = desc->more;
- if (desc->shadow_ptes[RMAP_EXT-1]) {
- desc->more = mmu_alloc_rmap_desc(vcpu);
- desc = desc->more;
- }
- for (i = 0; desc->shadow_ptes[i]; ++i)
- ;
- desc->shadow_ptes[i] = spte;
- }
-}
-
-static void rmap_desc_remove_entry(unsigned long *rmapp,
- struct kvm_rmap_desc *desc,
- int i,
- struct kvm_rmap_desc *prev_desc)
-{
- int j;
-
- for (j = RMAP_EXT - 1; !desc->shadow_ptes[j] && j > i; --j)
- ;
- desc->shadow_ptes[i] = desc->shadow_ptes[j];
- desc->shadow_ptes[j] = NULL;
- if (j != 0)
- return;
- if (!prev_desc && !desc->more)
- *rmapp = (unsigned long)desc->shadow_ptes[0];
- else
- if (prev_desc)
- prev_desc->more = desc->more;
- else
- *rmapp = (unsigned long)desc->more | 1;
- mmu_free_rmap_desc(desc);
-}
-
-static void rmap_remove(struct kvm *kvm, u64 *spte)
-{
- struct kvm_rmap_desc *desc;
- struct kvm_rmap_desc *prev_desc;
- struct kvm_mmu_page *sp;
- struct page *page;
- unsigned long *rmapp;
- int i;
-
- if (!is_rmap_pte(*spte))
- return;
- sp = page_header(__pa(spte));
- page = pfn_to_page((*spte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT);
- mark_page_accessed(page);
- if (is_writeble_pte(*spte))
- kvm_release_page_dirty(page);
- else
- kvm_release_page_clean(page);
- rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt]);
- if (!*rmapp) {
- printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte);
- BUG();
- } else if (!(*rmapp & 1)) {
- rmap_printk("rmap_remove: %p %llx 1->0\n", spte, *spte);
- if ((u64 *)*rmapp != spte) {
- printk(KERN_ERR "rmap_remove: %p %llx 1->BUG\n",
- spte, *spte);
- BUG();
- }
- *rmapp = 0;
- } else {
- rmap_printk("rmap_remove: %p %llx many->many\n", spte, *spte);
- desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
- prev_desc = NULL;
- while (desc) {
- for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i)
- if (desc->shadow_ptes[i] == spte) {
- rmap_desc_remove_entry(rmapp,
- desc, i,
- prev_desc);
- return;
- }
- prev_desc = desc;
- desc = desc->more;
- }
- BUG();
- }
-}
-
-static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte)
-{
- struct kvm_rmap_desc *desc;
- struct kvm_rmap_desc *prev_desc;
- u64 *prev_spte;
- int i;
-
- if (!*rmapp)
- return NULL;
- else if (!(*rmapp & 1)) {
- if (!spte)
- return (u64 *)*rmapp;
- return NULL;
- }
- desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
- prev_desc = NULL;
- prev_spte = NULL;
- while (desc) {
- for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i) {
- if (prev_spte == spte)
- return desc->shadow_ptes[i];
- prev_spte = desc->shadow_ptes[i];
- }
- desc = desc->more;
- }
- return NULL;
-}
-
-static void rmap_write_protect(struct kvm *kvm, u64 gfn)
-{
- unsigned long *rmapp;
- u64 *spte;
-
- gfn = unalias_gfn(kvm, gfn);
- rmapp = gfn_to_rmap(kvm, gfn);
-
- spte = rmap_next(kvm, rmapp, NULL);
- while (spte) {
- BUG_ON(!spte);
- BUG_ON(!(*spte & PT_PRESENT_MASK));
- rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte);
- if (is_writeble_pte(*spte))
- set_shadow_pte(spte, *spte & ~PT_WRITABLE_MASK);
- kvm_flush_remote_tlbs(kvm);
- spte = rmap_next(kvm, rmapp, spte);
- }
-}
-
-#ifdef MMU_DEBUG
-static int is_empty_shadow_page(u64 *spt)
-{
- u64 *pos;
- u64 *end;
-
- for (pos = spt, end = pos + PAGE_SIZE / sizeof(u64); pos != end; pos++)
- if ((*pos & ~PT_SHADOW_IO_MARK) != shadow_trap_nonpresent_pte) {
- printk(KERN_ERR "%s: %p %llx\n", __FUNCTION__,
- pos, *pos);
- return 0;
- }
- return 1;
-}
-#endif
-
-static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
-{
- ASSERT(is_empty_shadow_page(sp->spt));
- list_del(&sp->link);
- __free_page(virt_to_page(sp->spt));
- __free_page(virt_to_page(sp->gfns));
- kfree(sp);
- ++kvm->arch.n_free_mmu_pages;
-}
-
-static unsigned kvm_page_table_hashfn(gfn_t gfn)
-{
- return gfn;
-}
-
-static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
- u64 *parent_pte)
-{
- struct kvm_mmu_page *sp;
-
- if (!vcpu->kvm->arch.n_free_mmu_pages)
- return NULL;
-
- sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache, sizeof *sp);
- sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
- sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
- set_page_private(virt_to_page(sp->spt), (unsigned long)sp);
- list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages);
- ASSERT(is_empty_shadow_page(sp->spt));
- sp->slot_bitmap = 0;
- sp->multimapped = 0;
- sp->parent_pte = parent_pte;
- --vcpu->kvm->arch.n_free_mmu_pages;
- return sp;
-}
-
-static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu,
- struct kvm_mmu_page *sp, u64 *parent_pte)
-{
- struct kvm_pte_chain *pte_chain;
- struct hlist_node *node;
- int i;
-
- if (!parent_pte)
- return;
- if (!sp->multimapped) {
- u64 *old = sp->parent_pte;
-
- if (!old) {
- sp->parent_pte = parent_pte;
- return;
- }
- sp->multimapped = 1;
- pte_chain = mmu_alloc_pte_chain(vcpu);
- INIT_HLIST_HEAD(&sp->parent_ptes);
- hlist_add_head(&pte_chain->link, &sp->parent_ptes);
- pte_chain->parent_ptes[0] = old;
- }
- hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) {
- if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1])
- continue;
- for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i)
- if (!pte_chain->parent_ptes[i]) {
- pte_chain->parent_ptes[i] = parent_pte;
- return;
- }
- }
- pte_chain = mmu_alloc_pte_chain(vcpu);
- BUG_ON(!pte_chain);
- hlist_add_head(&pte_chain->link, &sp->parent_ptes);
- pte_chain->parent_ptes[0] = parent_pte;
-}
-
-static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
- u64 *parent_pte)
-{
- struct kvm_pte_chain *pte_chain;
- struct hlist_node *node;
- int i;
-
- if (!sp->multimapped) {
- BUG_ON(sp->parent_pte != parent_pte);
- sp->parent_pte = NULL;
- return;
- }
- hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
- for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
- if (!pte_chain->parent_ptes[i])
- break;
- if (pte_chain->parent_ptes[i] != parent_pte)
- continue;
- while (i + 1 < NR_PTE_CHAIN_ENTRIES
- && pte_chain->parent_ptes[i + 1]) {
- pte_chain->parent_ptes[i]
- = pte_chain->parent_ptes[i + 1];
- ++i;
- }
- pte_chain->parent_ptes[i] = NULL;
- if (i == 0) {
- hlist_del(&pte_chain->link);
- mmu_free_pte_chain(pte_chain);
- if (hlist_empty(&sp->parent_ptes)) {
- sp->multimapped = 0;
- sp->parent_pte = NULL;
- }
- }
- return;
- }
- BUG();
-}
-
-static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn)
-{
- unsigned index;
- struct hlist_head *bucket;
- struct kvm_mmu_page *sp;
- struct hlist_node *node;
-
- pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn);
- index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
- bucket = &kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry(sp, node, bucket, hash_link)
- if (sp->gfn == gfn && !sp->role.metaphysical) {
- pgprintk("%s: found role %x\n",
- __FUNCTION__, sp->role.word);
- return sp;
- }
- return NULL;
-}
-
-static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
- gfn_t gfn,
- gva_t gaddr,
- unsigned level,
- int metaphysical,
- unsigned access,
- u64 *parent_pte,
- bool *new_page)
-{
- union kvm_mmu_page_role role;
- unsigned index;
- unsigned quadrant;
- struct hlist_head *bucket;
- struct kvm_mmu_page *sp;
- struct hlist_node *node;
-
- role.word = 0;
- role.glevels = vcpu->arch.mmu.root_level;
- role.level = level;
- role.metaphysical = metaphysical;
- role.access = access;
- if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) {
- quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level));
- quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1;
- role.quadrant = quadrant;
- }
- pgprintk("%s: looking gfn %lx role %x\n", __FUNCTION__,
- gfn, role.word);
- index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry(sp, node, bucket, hash_link)
- if (sp->gfn == gfn && sp->role.word == role.word) {
- mmu_page_add_parent_pte(vcpu, sp, parent_pte);
- pgprintk("%s: found\n", __FUNCTION__);
- return sp;
- }
- sp = kvm_mmu_alloc_page(vcpu, parent_pte);
- if (!sp)
- return sp;
- pgprintk("%s: adding gfn %lx role %x\n", __FUNCTION__, gfn, role.word);
- sp->gfn = gfn;
- sp->role = role;
- hlist_add_head(&sp->hash_link, bucket);
- vcpu->arch.mmu.prefetch_page(vcpu, sp);
- if (!metaphysical)
- rmap_write_protect(vcpu->kvm, gfn);
- if (new_page)
- *new_page = 1;
- return sp;
-}
-
-static void kvm_mmu_page_unlink_children(struct kvm *kvm,
- struct kvm_mmu_page *sp)
-{
- unsigned i;
- u64 *pt;
- u64 ent;
-
- pt = sp->spt;
-
- if (sp->role.level == PT_PAGE_TABLE_LEVEL) {
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
- if (is_shadow_present_pte(pt[i]))
- rmap_remove(kvm, &pt[i]);
- pt[i] = shadow_trap_nonpresent_pte;
- }
- kvm_flush_remote_tlbs(kvm);
- return;
- }
-
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
- ent = pt[i];
-
- pt[i] = shadow_trap_nonpresent_pte;
- if (!is_shadow_present_pte(ent))
- continue;
- ent &= PT64_BASE_ADDR_MASK;
- mmu_page_remove_parent_pte(page_header(ent), &pt[i]);
- }
- kvm_flush_remote_tlbs(kvm);
-}
-
-static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte)
-{
- mmu_page_remove_parent_pte(sp, parent_pte);
-}
-
-static void kvm_mmu_reset_last_pte_updated(struct kvm *kvm)
-{
- int i;
-
- for (i = 0; i < KVM_MAX_VCPUS; ++i)
- if (kvm->vcpus[i])
- kvm->vcpus[i]->arch.last_pte_updated = NULL;
-}
-
-static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
-{
- u64 *parent_pte;
-
- ++kvm->stat.mmu_shadow_zapped;
- while (sp->multimapped || sp->parent_pte) {
- if (!sp->multimapped)
- parent_pte = sp->parent_pte;
- else {
- struct kvm_pte_chain *chain;
-
- chain = container_of(sp->parent_ptes.first,
- struct kvm_pte_chain, link);
- parent_pte = chain->parent_ptes[0];
- }
- BUG_ON(!parent_pte);
- kvm_mmu_put_page(sp, parent_pte);
- set_shadow_pte(parent_pte, shadow_trap_nonpresent_pte);
- }
- kvm_mmu_page_unlink_children(kvm, sp);
- if (!sp->root_count) {
- hlist_del(&sp->hash_link);
- kvm_mmu_free_page(kvm, sp);
- } else
- list_move(&sp->link, &kvm->arch.active_mmu_pages);
- kvm_mmu_reset_last_pte_updated(kvm);
-}
-
-/*
- * Changing the number of mmu pages allocated to the vm
- * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
- */
-void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)
-{
- /*
- * If we set the number of mmu pages to be smaller be than the
- * number of actived pages , we must to free some mmu pages before we
- * change the value
- */
-
- if ((kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages) >
- kvm_nr_mmu_pages) {
- int n_used_mmu_pages = kvm->arch.n_alloc_mmu_pages
- - kvm->arch.n_free_mmu_pages;
-
- while (n_used_mmu_pages > kvm_nr_mmu_pages) {
- struct kvm_mmu_page *page;
-
- page = container_of(kvm->arch.active_mmu_pages.prev,
- struct kvm_mmu_page, link);
- kvm_mmu_zap_page(kvm, page);
- n_used_mmu_pages--;
- }
- kvm->arch.n_free_mmu_pages = 0;
- }
- else
- kvm->arch.n_free_mmu_pages += kvm_nr_mmu_pages
- - kvm->arch.n_alloc_mmu_pages;
-
- kvm->arch.n_alloc_mmu_pages = kvm_nr_mmu_pages;
-}
-
-static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn)
-{
- unsigned index;
- struct hlist_head *bucket;
- struct kvm_mmu_page *sp;
- struct hlist_node *node, *n;
- int r;
-
- pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn);
- r = 0;
- index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
- bucket = &kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry_safe(sp, node, n, bucket, hash_link)
- if (sp->gfn == gfn && !sp->role.metaphysical) {
- pgprintk("%s: gfn %lx role %x\n", __FUNCTION__, gfn,
- sp->role.word);
- kvm_mmu_zap_page(kvm, sp);
- r = 1;
- }
- return r;
-}
-
-static void mmu_unshadow(struct kvm *kvm, gfn_t gfn)
-{
- struct kvm_mmu_page *sp;
-
- while ((sp = kvm_mmu_lookup_page(kvm, gfn)) != NULL) {
- pgprintk("%s: zap %lx %x\n", __FUNCTION__, gfn, sp->role.word);
- kvm_mmu_zap_page(kvm, sp);
- }
-}
-
-static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn)
-{
- int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn));
- struct kvm_mmu_page *sp = page_header(__pa(pte));
-
- __set_bit(slot, &sp->slot_bitmap);
-}
-
-struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva)
-{
- gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva);
-
- if (gpa == UNMAPPED_GVA)
- return NULL;
- return gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);
-}
-
-static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
- unsigned pt_access, unsigned pte_access,
- int user_fault, int write_fault, int dirty,
- int *ptwrite, gfn_t gfn)
-{
- u64 spte;
- int was_rmapped = is_rmap_pte(*shadow_pte);
- struct page *page;
-
- pgprintk("%s: spte %llx access %x write_fault %d"
- " user_fault %d gfn %lx\n",
- __FUNCTION__, *shadow_pte, pt_access,
- write_fault, user_fault, gfn);
-
- /*
- * We don't set the accessed bit, since we sometimes want to see
- * whether the guest actually used the pte (in order to detect
- * demand paging).
- */
- spte = PT_PRESENT_MASK | PT_DIRTY_MASK;
- if (!dirty)
- pte_access &= ~ACC_WRITE_MASK;
- if (!(pte_access & ACC_EXEC_MASK))
- spte |= PT64_NX_MASK;
-
- page = gfn_to_page(vcpu->kvm, gfn);
-
- spte |= PT_PRESENT_MASK;
- if (pte_access & ACC_USER_MASK)
- spte |= PT_USER_MASK;
-
- if (is_error_page(page)) {
- set_shadow_pte(shadow_pte,
- shadow_trap_nonpresent_pte | PT_SHADOW_IO_MARK);
- kvm_release_page_clean(page);
- return;
- }
-
- spte |= page_to_phys(page);
-
- if ((pte_access & ACC_WRITE_MASK)
- || (write_fault && !is_write_protection(vcpu) && !user_fault)) {
- struct kvm_mmu_page *shadow;
-
- spte |= PT_WRITABLE_MASK;
- if (user_fault) {
- mmu_unshadow(vcpu->kvm, gfn);
- goto unshadowed;
- }
-
- shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn);
- if (shadow) {
- pgprintk("%s: found shadow page for %lx, marking ro\n",
- __FUNCTION__, gfn);
- pte_access &= ~ACC_WRITE_MASK;
- if (is_writeble_pte(spte)) {
- spte &= ~PT_WRITABLE_MASK;
- kvm_x86_ops->tlb_flush(vcpu);
- }
- if (write_fault)
- *ptwrite = 1;
- }
- }
-
-unshadowed:
-
- if (pte_access & ACC_WRITE_MASK)
- mark_page_dirty(vcpu->kvm, gfn);
-
- pgprintk("%s: setting spte %llx\n", __FUNCTION__, spte);
- set_shadow_pte(shadow_pte, spte);
- page_header_update_slot(vcpu->kvm, shadow_pte, gfn);
- if (!was_rmapped) {
- rmap_add(vcpu, shadow_pte, gfn);
- if (!is_rmap_pte(*shadow_pte))
- kvm_release_page_clean(page);
- }
- else
- kvm_release_page_clean(page);
- if (!ptwrite || !*ptwrite)
- vcpu->arch.last_pte_updated = shadow_pte;
-}
-
-static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
-{
-}
-
-static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
-{
- int level = PT32E_ROOT_LEVEL;
- hpa_t table_addr = vcpu->arch.mmu.root_hpa;
- int pt_write = 0;
-
- for (; ; level--) {
- u32 index = PT64_INDEX(v, level);
- u64 *table;
-
- ASSERT(VALID_PAGE(table_addr));
- table = __va(table_addr);
-
- if (level == 1) {
- mmu_set_spte(vcpu, &table[index], ACC_ALL, ACC_ALL,
- 0, write, 1, &pt_write, gfn);
- return pt_write || is_io_pte(table[index]);
- }
-
- if (table[index] == shadow_trap_nonpresent_pte) {
- struct kvm_mmu_page *new_table;
- gfn_t pseudo_gfn;
-
- pseudo_gfn = (v & PT64_DIR_BASE_ADDR_MASK)
- >> PAGE_SHIFT;
- new_table = kvm_mmu_get_page(vcpu, pseudo_gfn,
- v, level - 1,
- 1, ACC_ALL, &table[index],
- NULL);
- if (!new_table) {
- pgprintk("nonpaging_map: ENOMEM\n");
- return -ENOMEM;
- }
-
- table[index] = __pa(new_table->spt) | PT_PRESENT_MASK
- | PT_WRITABLE_MASK | PT_USER_MASK;
- }
- table_addr = table[index] & PT64_BASE_ADDR_MASK;
- }
-}
-
-static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
- struct kvm_mmu_page *sp)
-{
- int i;
-
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
- sp->spt[i] = shadow_trap_nonpresent_pte;
-}
-
-static void mmu_free_roots(struct kvm_vcpu *vcpu)
-{
- int i;
- struct kvm_mmu_page *sp;
-
- if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
- return;
-#ifdef CONFIG_X86_64
- if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
- hpa_t root = vcpu->arch.mmu.root_hpa;
-
- sp = page_header(root);
- --sp->root_count;
- vcpu->arch.mmu.root_hpa = INVALID_PAGE;
- return;
- }
-#endif
- for (i = 0; i < 4; ++i) {
- hpa_t root = vcpu->arch.mmu.pae_root[i];
-
- if (root) {
- root &= PT64_BASE_ADDR_MASK;
- sp = page_header(root);
- --sp->root_count;
- }
- vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
- }
- vcpu->arch.mmu.root_hpa = INVALID_PAGE;
-}
-
-static void mmu_alloc_roots(struct kvm_vcpu *vcpu)
-{
- int i;
- gfn_t root_gfn;
- struct kvm_mmu_page *sp;
-
- root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
-
-#ifdef CONFIG_X86_64
- if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
- hpa_t root = vcpu->arch.mmu.root_hpa;
-
- ASSERT(!VALID_PAGE(root));
- sp = kvm_mmu_get_page(vcpu, root_gfn, 0,
- PT64_ROOT_LEVEL, 0, ACC_ALL, NULL, NULL);
- root = __pa(sp->spt);
- ++sp->root_count;
- vcpu->arch.mmu.root_hpa = root;
- return;
- }
-#endif
- for (i = 0; i < 4; ++i) {
- hpa_t root = vcpu->arch.mmu.pae_root[i];
-
- ASSERT(!VALID_PAGE(root));
- if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) {
- if (!is_present_pte(vcpu->arch.pdptrs[i])) {
- vcpu->arch.mmu.pae_root[i] = 0;
- continue;
- }
- root_gfn = vcpu->arch.pdptrs[i] >> PAGE_SHIFT;
- } else if (vcpu->arch.mmu.root_level == 0)
- root_gfn = 0;
- sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
- PT32_ROOT_LEVEL, !is_paging(vcpu),
- ACC_ALL, NULL, NULL);
- root = __pa(sp->spt);
- ++sp->root_count;
- vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK;
- }
- vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
-}
-
-static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr)
-{
- return vaddr;
-}
-
-static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
- u32 error_code)
-{
- gfn_t gfn;
- int r;
-
- pgprintk("%s: gva %lx error %x\n", __FUNCTION__, gva, error_code);
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- return r;
-
- ASSERT(vcpu);
- ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));
-
- gfn = gva >> PAGE_SHIFT;
-
- return nonpaging_map(vcpu, gva & PAGE_MASK,
- error_code & PFERR_WRITE_MASK, gfn);
-}
-
-static void nonpaging_free(struct kvm_vcpu *vcpu)
-{
- mmu_free_roots(vcpu);
-}
-
-static int nonpaging_init_context(struct kvm_vcpu *vcpu)
-{
- struct kvm_mmu *context = &vcpu->arch.mmu;
-
- context->new_cr3 = nonpaging_new_cr3;
- context->page_fault = nonpaging_page_fault;
- context->gva_to_gpa = nonpaging_gva_to_gpa;
- context->free = nonpaging_free;
- context->prefetch_page = nonpaging_prefetch_page;
- context->root_level = 0;
- context->shadow_root_level = PT32E_ROOT_LEVEL;
- context->root_hpa = INVALID_PAGE;
- return 0;
-}
-
-void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu)
-{
- ++vcpu->stat.tlb_flush;
- kvm_x86_ops->tlb_flush(vcpu);
-}
-
-static void paging_new_cr3(struct kvm_vcpu *vcpu)
-{
- pgprintk("%s: cr3 %lx\n", __FUNCTION__, vcpu->cr3);
- mmu_free_roots(vcpu);
-}
-
-static void inject_page_fault(struct kvm_vcpu *vcpu,
- u64 addr,
- u32 err_code)
-{
- kvm_inject_page_fault(vcpu, addr, err_code);
-}
-
-static void paging_free(struct kvm_vcpu *vcpu)
-{
- nonpaging_free(vcpu);
-}
-
-#define PTTYPE 64
-#include "paging_tmpl.h"
-#undef PTTYPE
-
-#define PTTYPE 32
-#include "paging_tmpl.h"
-#undef PTTYPE
-
-static int paging64_init_context_common(struct kvm_vcpu *vcpu, int level)
-{
- struct kvm_mmu *context = &vcpu->arch.mmu;
-
- ASSERT(is_pae(vcpu));
- context->new_cr3 = paging_new_cr3;
- context->page_fault = paging64_page_fault;
- context->gva_to_gpa = paging64_gva_to_gpa;
- context->prefetch_page = paging64_prefetch_page;
- context->free = paging_free;
- context->root_level = level;
- context->shadow_root_level = level;
- context->root_hpa = INVALID_PAGE;
- return 0;
-}
-
-static int paging64_init_context(struct kvm_vcpu *vcpu)
-{
- return paging64_init_context_common(vcpu, PT64_ROOT_LEVEL);
-}
-
-static int paging32_init_context(struct kvm_vcpu *vcpu)
-{
- struct kvm_mmu *context = &vcpu->arch.mmu;
-
- context->new_cr3 = paging_new_cr3;
- context->page_fault = paging32_page_fault;
- context->gva_to_gpa = paging32_gva_to_gpa;
- context->free = paging_free;
- context->prefetch_page = paging32_prefetch_page;
- context->root_level = PT32_ROOT_LEVEL;
- context->shadow_root_level = PT32E_ROOT_LEVEL;
- context->root_hpa = INVALID_PAGE;
- return 0;
-}
-
-static int paging32E_init_context(struct kvm_vcpu *vcpu)
-{
- return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL);
-}
-
-static int init_kvm_mmu(struct kvm_vcpu *vcpu)
-{
- ASSERT(vcpu);
- ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
-
- if (!is_paging(vcpu))
- return nonpaging_init_context(vcpu);
- else if (is_long_mode(vcpu))
- return paging64_init_context(vcpu);
- else if (is_pae(vcpu))
- return paging32E_init_context(vcpu);
- else
- return paging32_init_context(vcpu);
-}
-
-static void destroy_kvm_mmu(struct kvm_vcpu *vcpu)
-{
- ASSERT(vcpu);
- if (VALID_PAGE(vcpu->arch.mmu.root_hpa)) {
- vcpu->arch.mmu.free(vcpu);
- vcpu->arch.mmu.root_hpa = INVALID_PAGE;
- }
-}
-
-int kvm_mmu_reset_context(struct kvm_vcpu *vcpu)
-{
- destroy_kvm_mmu(vcpu);
- return init_kvm_mmu(vcpu);
-}
-EXPORT_SYMBOL_GPL(kvm_mmu_reset_context);
-
-int kvm_mmu_load(struct kvm_vcpu *vcpu)
-{
- int r;
-
- mutex_lock(&vcpu->kvm->lock);
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- goto out;
- mmu_alloc_roots(vcpu);
- kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa);
- kvm_mmu_flush_tlb(vcpu);
-out:
- mutex_unlock(&vcpu->kvm->lock);
- return r;
-}
-EXPORT_SYMBOL_GPL(kvm_mmu_load);
-
-void kvm_mmu_unload(struct kvm_vcpu *vcpu)
-{
- mmu_free_roots(vcpu);
-}
-
-static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
- struct kvm_mmu_page *sp,
- u64 *spte)
-{
- u64 pte;
- struct kvm_mmu_page *child;
-
- pte = *spte;
- if (is_shadow_present_pte(pte)) {
- if (sp->role.level == PT_PAGE_TABLE_LEVEL)
- rmap_remove(vcpu->kvm, spte);
- else {
- child = page_header(pte & PT64_BASE_ADDR_MASK);
- mmu_page_remove_parent_pte(child, spte);
- }
- }
- set_shadow_pte(spte, shadow_trap_nonpresent_pte);
-}
-
-static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
- struct kvm_mmu_page *sp,
- u64 *spte,
- const void *new, int bytes,
- int offset_in_pte)
-{
- if (sp->role.level != PT_PAGE_TABLE_LEVEL) {
- ++vcpu->kvm->stat.mmu_pde_zapped;
- return;
- }
-
- ++vcpu->kvm->stat.mmu_pte_updated;
- if (sp->role.glevels == PT32_ROOT_LEVEL)
- paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte);
- else
- paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte);
-}
-
-static bool need_remote_flush(u64 old, u64 new)
-{
- if (!is_shadow_present_pte(old))
- return false;
- if (!is_shadow_present_pte(new))
- return true;
- if ((old ^ new) & PT64_BASE_ADDR_MASK)
- return true;
- old ^= PT64_NX_MASK;
- new ^= PT64_NX_MASK;
- return (old & ~new & PT64_PERM_MASK) != 0;
-}
-
-static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, u64 old, u64 new)
-{
- if (need_remote_flush(old, new))
- kvm_flush_remote_tlbs(vcpu->kvm);
- else
- kvm_mmu_flush_tlb(vcpu);
-}
-
-static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu)
-{
- u64 *spte = vcpu->arch.last_pte_updated;
-
- return !!(spte && (*spte & PT_ACCESSED_MASK));
-}
-
-void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
- const u8 *new, int bytes)
-{
- gfn_t gfn = gpa >> PAGE_SHIFT;
- struct kvm_mmu_page *sp;
- struct hlist_node *node, *n;
- struct hlist_head *bucket;
- unsigned index;
- u64 entry;
- u64 *spte;
- unsigned offset = offset_in_page(gpa);
- unsigned pte_size;
- unsigned page_offset;
- unsigned misaligned;
- unsigned quadrant;
- int level;
- int flooded = 0;
- int npte;
-
- pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes);
- ++vcpu->kvm->stat.mmu_pte_write;
- kvm_mmu_audit(vcpu, "pre pte write");
- if (gfn == vcpu->arch.last_pt_write_gfn
- && !last_updated_pte_accessed(vcpu)) {
- ++vcpu->arch.last_pt_write_count;
- if (vcpu->arch.last_pt_write_count >= 3)
- flooded = 1;
- } else {
- vcpu->arch.last_pt_write_gfn = gfn;
- vcpu->arch.last_pt_write_count = 1;
- vcpu->arch.last_pte_updated = NULL;
- }
- index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
- bucket = &vcpu->kvm->arch.mmu_page_hash[index];
- hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) {
- if (sp->gfn != gfn || sp->role.metaphysical)
- continue;
- pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8;
- misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1);
- misaligned |= bytes < 4;
- if (misaligned || flooded) {
- /*
- * Misaligned accesses are too much trouble to fix
- * up; also, they usually indicate a page is not used
- * as a page table.
- *
- * If we're seeing too many writes to a page,
- * it may no longer be a page table, or we may be
- * forking, in which case it is better to unmap the
- * page.
- */
- pgprintk("misaligned: gpa %llx bytes %d role %x\n",
- gpa, bytes, sp->role.word);
- kvm_mmu_zap_page(vcpu->kvm, sp);
- ++vcpu->kvm->stat.mmu_flooded;
- continue;
- }
- page_offset = offset;
- level = sp->role.level;
- npte = 1;
- if (sp->role.glevels == PT32_ROOT_LEVEL) {
- page_offset <<= 1; /* 32->64 */
- /*
- * A 32-bit pde maps 4MB while the shadow pdes map
- * only 2MB. So we need to double the offset again
- * and zap two pdes instead of one.
- */
- if (level == PT32_ROOT_LEVEL) {
- page_offset &= ~7; /* kill rounding error */
- page_offset <<= 1;
- npte = 2;
- }
- quadrant = page_offset >> PAGE_SHIFT;
- page_offset &= ~PAGE_MASK;
- if (quadrant != sp->role.quadrant)
- continue;
- }
- spte = &sp->spt[page_offset / sizeof(*spte)];
- while (npte--) {
- entry = *spte;
- mmu_pte_write_zap_pte(vcpu, sp, spte);
- mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes,
- page_offset & (pte_size - 1));
- mmu_pte_write_flush_tlb(vcpu, entry, *spte);
- ++spte;
- }
- }
- kvm_mmu_audit(vcpu, "post pte write");
-}
-
-int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
-{
- gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva);
-
- return kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT);
-}
-
-void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
-{
- while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) {
- struct kvm_mmu_page *sp;
-
- sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev,
- struct kvm_mmu_page, link);
- kvm_mmu_zap_page(vcpu->kvm, sp);
- ++vcpu->kvm->stat.mmu_recycled;
- }
-}
-
-int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code)
-{
- int r;
- enum emulation_result er;
-
- mutex_lock(&vcpu->kvm->lock);
- r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code);
- if (r < 0)
- goto out;
-
- if (!r) {
- r = 1;
- goto out;
- }
-
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- goto out;
-
- er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0);
- mutex_unlock(&vcpu->kvm->lock);
-
- switch (er) {
- case EMULATE_DONE:
- return 1;
- case EMULATE_DO_MMIO:
- ++vcpu->stat.mmio_exits;
- return 0;
- case EMULATE_FAIL:
- kvm_report_emulation_failure(vcpu, "pagetable");
- return 1;
- default:
- BUG();
- }
-out:
- mutex_unlock(&vcpu->kvm->lock);
- return r;
-}
-EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
-
-static void free_mmu_pages(struct kvm_vcpu *vcpu)
-{
- struct kvm_mmu_page *sp;
-
- while (!list_empty(&vcpu->kvm->arch.active_mmu_pages)) {
- sp = container_of(vcpu->kvm->arch.active_mmu_pages.next,
- struct kvm_mmu_page, link);
- kvm_mmu_zap_page(vcpu->kvm, sp);
- }
- free_page((unsigned long)vcpu->arch.mmu.pae_root);
-}
-
-static int alloc_mmu_pages(struct kvm_vcpu *vcpu)
-{
- struct page *page;
- int i;
-
- ASSERT(vcpu);
-
- if (vcpu->kvm->arch.n_requested_mmu_pages)
- vcpu->kvm->arch.n_free_mmu_pages =
- vcpu->kvm->arch.n_requested_mmu_pages;
- else
- vcpu->kvm->arch.n_free_mmu_pages =
- vcpu->kvm->arch.n_alloc_mmu_pages;
- /*
- * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
- * Therefore we need to allocate shadow page tables in the first
- * 4GB of memory, which happens to fit the DMA32 zone.
- */
- page = alloc_page(GFP_KERNEL | __GFP_DMA32);
- if (!page)
- goto error_1;
- vcpu->arch.mmu.pae_root = page_address(page);
- for (i = 0; i < 4; ++i)
- vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
-
- return 0;
-
-error_1:
- free_mmu_pages(vcpu);
- return -ENOMEM;
-}
-
-int kvm_mmu_create(struct kvm_vcpu *vcpu)
-{
- ASSERT(vcpu);
- ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
-
- return alloc_mmu_pages(vcpu);
-}
-
-int kvm_mmu_setup(struct kvm_vcpu *vcpu)
-{
- ASSERT(vcpu);
- ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
-
- return init_kvm_mmu(vcpu);
-}
-
-void kvm_mmu_destroy(struct kvm_vcpu *vcpu)
-{
- ASSERT(vcpu);
-
- destroy_kvm_mmu(vcpu);
- free_mmu_pages(vcpu);
- mmu_free_memory_caches(vcpu);
-}
-
-void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
-{
- struct kvm_mmu_page *sp;
-
- list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) {
- int i;
- u64 *pt;
-
- if (!test_bit(slot, &sp->slot_bitmap))
- continue;
-
- pt = sp->spt;
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
- /* avoid RMW */
- if (pt[i] & PT_WRITABLE_MASK)
- pt[i] &= ~PT_WRITABLE_MASK;
- }
-}
-
-void kvm_mmu_zap_all(struct kvm *kvm)
-{
- struct kvm_mmu_page *sp, *node;
-
- list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link)
- kvm_mmu_zap_page(kvm, sp);
-
- kvm_flush_remote_tlbs(kvm);
-}
-
-void kvm_mmu_module_exit(void)
-{
- if (pte_chain_cache)
- kmem_cache_destroy(pte_chain_cache);
- if (rmap_desc_cache)
- kmem_cache_destroy(rmap_desc_cache);
- if (mmu_page_header_cache)
- kmem_cache_destroy(mmu_page_header_cache);
-}
-
-int kvm_mmu_module_init(void)
-{
- pte_chain_cache = kmem_cache_create("kvm_pte_chain",
- sizeof(struct kvm_pte_chain),
- 0, 0, NULL);
- if (!pte_chain_cache)
- goto nomem;
- rmap_desc_cache = kmem_cache_create("kvm_rmap_desc",
- sizeof(struct kvm_rmap_desc),
- 0, 0, NULL);
- if (!rmap_desc_cache)
- goto nomem;
-
- mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header",
- sizeof(struct kvm_mmu_page),
- 0, 0, NULL);
- if (!mmu_page_header_cache)
- goto nomem;
-
- return 0;
-
-nomem:
- kvm_mmu_module_exit();
- return -ENOMEM;
-}
-
-/*
- * Caculate mmu pages needed for kvm.
- */
-unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm)
-{
- int i;
- unsigned int nr_mmu_pages;
- unsigned int nr_pages = 0;
-
- for (i = 0; i < kvm->nmemslots; i++)
- nr_pages += kvm->memslots[i].npages;
-
- nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000;
- nr_mmu_pages = max(nr_mmu_pages,
- (unsigned int) KVM_MIN_ALLOC_MMU_PAGES);
-
- return nr_mmu_pages;
-}
-
-#ifdef AUDIT
-
-static const char *audit_msg;
-
-static gva_t canonicalize(gva_t gva)
-{
-#ifdef CONFIG_X86_64
- gva = (long long)(gva << 16) >> 16;
-#endif
- return gva;
-}
-
-static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
- gva_t va, int level)
-{
- u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK);
- int i;
- gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1));
-
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) {
- u64 ent = pt[i];
-
- if (ent == shadow_trap_nonpresent_pte)
- continue;
-
- va = canonicalize(va);
- if (level > 1) {
- if (ent == shadow_notrap_nonpresent_pte)
- printk(KERN_ERR "audit: (%s) nontrapping pte"
- " in nonleaf level: levels %d gva %lx"
- " level %d pte %llx\n", audit_msg,
- vcpu->arch.mmu.root_level, va, level, ent);
-
- audit_mappings_page(vcpu, ent, va, level - 1);
- } else {
- gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va);
- struct page *page = gpa_to_page(vcpu, gpa);
- hpa_t hpa = page_to_phys(page);
-
- if (is_shadow_present_pte(ent)
- && (ent & PT64_BASE_ADDR_MASK) != hpa)
- printk(KERN_ERR "xx audit error: (%s) levels %d"
- " gva %lx gpa %llx hpa %llx ent %llx %d\n",
- audit_msg, vcpu->arch.mmu.root_level,
- va, gpa, hpa, ent,
- is_shadow_present_pte(ent));
- else if (ent == shadow_notrap_nonpresent_pte
- && !is_error_hpa(hpa))
- printk(KERN_ERR "audit: (%s) notrap shadow,"
- " valid guest gva %lx\n", audit_msg, va);
- kvm_release_page_clean(page);
-
- }
- }
-}
-
-static void audit_mappings(struct kvm_vcpu *vcpu)
-{
- unsigned i;
-
- if (vcpu->arch.mmu.root_level == 4)
- audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4);
- else
- for (i = 0; i < 4; ++i)
- if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK)
- audit_mappings_page(vcpu,
- vcpu->arch.mmu.pae_root[i],
- i << 30,
- 2);
-}
-
-static int count_rmaps(struct kvm_vcpu *vcpu)
-{
- int nmaps = 0;
- int i, j, k;
-
- for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
- struct kvm_memory_slot *m = &vcpu->kvm->memslots[i];
- struct kvm_rmap_desc *d;
-
- for (j = 0; j < m->npages; ++j) {
- unsigned long *rmapp = &m->rmap[j];
-
- if (!*rmapp)
- continue;
- if (!(*rmapp & 1)) {
- ++nmaps;
- continue;
- }
- d = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
- while (d) {
- for (k = 0; k < RMAP_EXT; ++k)
- if (d->shadow_ptes[k])
- ++nmaps;
- else
- break;
- d = d->more;
- }
- }
- }
- return nmaps;
-}
-
-static int count_writable_mappings(struct kvm_vcpu *vcpu)
-{
- int nmaps = 0;
- struct kvm_mmu_page *sp;
- int i;
-
- list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
- u64 *pt = sp->spt;
-
- if (sp->role.level != PT_PAGE_TABLE_LEVEL)
- continue;
-
- for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
- u64 ent = pt[i];
-
- if (!(ent & PT_PRESENT_MASK))
- continue;
- if (!(ent & PT_WRITABLE_MASK))
- continue;
- ++nmaps;
- }
- }
- return nmaps;
-}
-
-static void audit_rmap(struct kvm_vcpu *vcpu)
-{
- int n_rmap = count_rmaps(vcpu);
- int n_actual = count_writable_mappings(vcpu);
-
- if (n_rmap != n_actual)
- printk(KERN_ERR "%s: (%s) rmap %d actual %d\n",
- __FUNCTION__, audit_msg, n_rmap, n_actual);
-}
-
-static void audit_write_protection(struct kvm_vcpu *vcpu)
-{
- struct kvm_mmu_page *sp;
- struct kvm_memory_slot *slot;
- unsigned long *rmapp;
- gfn_t gfn;
-
- list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
- if (sp->role.metaphysical)
- continue;
-
- slot = gfn_to_memslot(vcpu->kvm, sp->gfn);
- gfn = unalias_gfn(vcpu->kvm, sp->gfn);
- rmapp = &slot->rmap[gfn - slot->base_gfn];
- if (*rmapp)
- printk(KERN_ERR "%s: (%s) shadow page has writable"
- " mappings: gfn %lx role %x\n",
- __FUNCTION__, audit_msg, sp->gfn,
- sp->role.word);
- }
-}
-
-static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg)
-{
- int olddbg = dbg;
-
- dbg = 0;
- audit_msg = msg;
- audit_rmap(vcpu);
- audit_write_protection(vcpu);
- audit_mappings(vcpu);
- dbg = olddbg;
-}
-
-#endif