diff options
Diffstat (limited to 'drivers/kvm/mmu.c')
| -rw-r--r-- | drivers/kvm/mmu.c | 686 |
1 files changed, 0 insertions, 686 deletions
diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c deleted file mode 100644 index 3d367cbfe1f..00000000000 --- a/drivers/kvm/mmu.c +++ /dev/null @@ -1,686 +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 <linux/types.h> -#include <linux/string.h> -#include <asm/page.h> -#include <linux/mm.h> -#include <linux/highmem.h> -#include <linux/module.h> - -#include "vmx.h" -#include "kvm.h" - -#define pgprintk(x...) do { } while (0) - -#define ASSERT(x) \ - if (!(x)) { \ - printk(KERN_WARNING "assertion failed %s:%d: %s\n", \ - __FILE__, __LINE__, #x); \ - } - -#define PT64_ENT_PER_PAGE 512 -#define PT32_ENT_PER_PAGE 1024 - -#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_MASK (1ULL << 63) - -#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 PT32_PTE_COPY_MASK \ - (PT_PRESENT_MASK | PT_ACCESSED_MASK | PT_DIRTY_MASK | PT_GLOBAL_MASK) - -#define PT64_PTE_COPY_MASK (PT64_NX_MASK | PT32_PTE_COPY_MASK) - -#define PT_FIRST_AVAIL_BITS_SHIFT 9 -#define PT64_SECOND_AVAIL_BITS_SHIFT 52 - -#define PT_SHADOW_PS_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) -#define PT_SHADOW_IO_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) - -#define PT_SHADOW_WRITABLE_SHIFT (PT_FIRST_AVAIL_BITS_SHIFT + 1) -#define PT_SHADOW_WRITABLE_MASK (1ULL << PT_SHADOW_WRITABLE_SHIFT) - -#define PT_SHADOW_USER_SHIFT (PT_SHADOW_WRITABLE_SHIFT + 1) -#define PT_SHADOW_USER_MASK (1ULL << (PT_SHADOW_USER_SHIFT)) - -#define PT_SHADOW_BITS_OFFSET (PT_SHADOW_WRITABLE_SHIFT - PT_WRITABLE_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) & PAGE_MASK) -#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 PFERR_PRESENT_MASK (1U << 0) -#define PFERR_WRITE_MASK (1U << 1) -#define PFERR_USER_MASK (1U << 2) - -#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 - -static int is_write_protection(struct kvm_vcpu *vcpu) -{ - return vcpu->cr0 & CR0_WP_MASK; -} - -static int is_cpuid_PSE36(void) -{ - return 1; -} - -static int is_present_pte(unsigned long pte) -{ - return pte & PT_PRESENT_MASK; -} - -static int is_writeble_pte(unsigned long pte) -{ - return pte & PT_WRITABLE_MASK; -} - -static int is_io_pte(unsigned long pte) -{ - return pte & PT_SHADOW_IO_MARK; -} - -static void kvm_mmu_free_page(struct kvm_vcpu *vcpu, hpa_t page_hpa) -{ - struct kvm_mmu_page *page_head = page_header(page_hpa); - - list_del(&page_head->link); - page_head->page_hpa = page_hpa; - list_add(&page_head->link, &vcpu->free_pages); -} - -static int is_empty_shadow_page(hpa_t page_hpa) -{ - u32 *pos; - u32 *end; - for (pos = __va(page_hpa), end = pos + PAGE_SIZE / sizeof(u32); - pos != end; pos++) - if (*pos != 0) - return 0; - return 1; -} - -static hpa_t kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, u64 *parent_pte) -{ - struct kvm_mmu_page *page; - - if (list_empty(&vcpu->free_pages)) - return INVALID_PAGE; - - page = list_entry(vcpu->free_pages.next, struct kvm_mmu_page, link); - list_del(&page->link); - list_add(&page->link, &vcpu->kvm->active_mmu_pages); - ASSERT(is_empty_shadow_page(page->page_hpa)); - page->slot_bitmap = 0; - page->global = 1; - page->parent_pte = parent_pte; - return page->page_hpa; -} - -static void page_header_update_slot(struct kvm *kvm, void *pte, gpa_t gpa) -{ - int slot = memslot_id(kvm, gfn_to_memslot(kvm, gpa >> PAGE_SHIFT)); - struct kvm_mmu_page *page_head = page_header(__pa(pte)); - - __set_bit(slot, &page_head->slot_bitmap); -} - -hpa_t safe_gpa_to_hpa(struct kvm_vcpu *vcpu, gpa_t gpa) -{ - hpa_t hpa = gpa_to_hpa(vcpu, gpa); - - return is_error_hpa(hpa) ? bad_page_address | (gpa & ~PAGE_MASK): hpa; -} - -hpa_t gpa_to_hpa(struct kvm_vcpu *vcpu, gpa_t gpa) -{ - struct kvm_memory_slot *slot; - struct page *page; - - ASSERT((gpa & HPA_ERR_MASK) == 0); - slot = gfn_to_memslot(vcpu->kvm, gpa >> PAGE_SHIFT); - if (!slot) - return gpa | HPA_ERR_MASK; - page = gfn_to_page(slot, gpa >> PAGE_SHIFT); - return ((hpa_t)page_to_pfn(page) << PAGE_SHIFT) - | (gpa & (PAGE_SIZE-1)); -} - -hpa_t gva_to_hpa(struct kvm_vcpu *vcpu, gva_t gva) -{ - gpa_t gpa = vcpu->mmu.gva_to_gpa(vcpu, gva); - - if (gpa == UNMAPPED_GVA) - return UNMAPPED_GVA; - return gpa_to_hpa(vcpu, gpa); -} - - -static void release_pt_page_64(struct kvm_vcpu *vcpu, hpa_t page_hpa, - int level) -{ - ASSERT(vcpu); - ASSERT(VALID_PAGE(page_hpa)); - ASSERT(level <= PT64_ROOT_LEVEL && level > 0); - - if (level == 1) - memset(__va(page_hpa), 0, PAGE_SIZE); - else { - u64 *pos; - u64 *end; - - for (pos = __va(page_hpa), end = pos + PT64_ENT_PER_PAGE; - pos != end; pos++) { - u64 current_ent = *pos; - - *pos = 0; - if (is_present_pte(current_ent)) - release_pt_page_64(vcpu, - current_ent & - PT64_BASE_ADDR_MASK, - level - 1); - } - } - kvm_mmu_free_page(vcpu, page_hpa); -} - -static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) -{ -} - -static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, hpa_t p) -{ - int level = PT32E_ROOT_LEVEL; - hpa_t table_addr = vcpu->mmu.root_hpa; - - for (; ; level--) { - u32 index = PT64_INDEX(v, level); - u64 *table; - - ASSERT(VALID_PAGE(table_addr)); - table = __va(table_addr); - - if (level == 1) { - mark_page_dirty(vcpu->kvm, v >> PAGE_SHIFT); - page_header_update_slot(vcpu->kvm, table, v); - table[index] = p | PT_PRESENT_MASK | PT_WRITABLE_MASK | - PT_USER_MASK; - return 0; - } - - if (table[index] == 0) { - hpa_t new_table = kvm_mmu_alloc_page(vcpu, - &table[index]); - - if (!VALID_PAGE(new_table)) { - pgprintk("nonpaging_map: ENOMEM\n"); - return -ENOMEM; - } - - if (level == PT32E_ROOT_LEVEL) - table[index] = new_table | PT_PRESENT_MASK; - else - table[index] = new_table | PT_PRESENT_MASK | - PT_WRITABLE_MASK | PT_USER_MASK; - } - table_addr = table[index] & PT64_BASE_ADDR_MASK; - } -} - -static void nonpaging_flush(struct kvm_vcpu *vcpu) -{ - hpa_t root = vcpu->mmu.root_hpa; - - ++kvm_stat.tlb_flush; - pgprintk("nonpaging_flush\n"); - ASSERT(VALID_PAGE(root)); - release_pt_page_64(vcpu, root, vcpu->mmu.shadow_root_level); - root = kvm_mmu_alloc_page(vcpu, NULL); - ASSERT(VALID_PAGE(root)); - vcpu->mmu.root_hpa = root; - if (is_paging(vcpu)) - root |= (vcpu->cr3 & (CR3_PCD_MASK | CR3_WPT_MASK)); - kvm_arch_ops->set_cr3(vcpu, root); - kvm_arch_ops->tlb_flush(vcpu); -} - -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) -{ - int ret; - gpa_t addr = gva; - - ASSERT(vcpu); - ASSERT(VALID_PAGE(vcpu->mmu.root_hpa)); - - for (;;) { - hpa_t paddr; - - paddr = gpa_to_hpa(vcpu , addr & PT64_BASE_ADDR_MASK); - - if (is_error_hpa(paddr)) - return 1; - - ret = nonpaging_map(vcpu, addr & PAGE_MASK, paddr); - if (ret) { - nonpaging_flush(vcpu); - continue; - } - break; - } - return ret; -} - -static void nonpaging_inval_page(struct kvm_vcpu *vcpu, gva_t addr) -{ -} - -static void nonpaging_free(struct kvm_vcpu *vcpu) -{ - hpa_t root; - - ASSERT(vcpu); - root = vcpu->mmu.root_hpa; - if (VALID_PAGE(root)) - release_pt_page_64(vcpu, root, vcpu->mmu.shadow_root_level); - vcpu->mmu.root_hpa = INVALID_PAGE; -} - -static int nonpaging_init_context(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu *context = &vcpu->mmu; - - context->new_cr3 = nonpaging_new_cr3; - context->page_fault = nonpaging_page_fault; - context->inval_page = nonpaging_inval_page; - context->gva_to_gpa = nonpaging_gva_to_gpa; - context->free = nonpaging_free; - context->root_level = PT32E_ROOT_LEVEL; - context->shadow_root_level = PT32E_ROOT_LEVEL; - context->root_hpa = kvm_mmu_alloc_page(vcpu, NULL); - ASSERT(VALID_PAGE(context->root_hpa)); - kvm_arch_ops->set_cr3(vcpu, context->root_hpa); - return 0; -} - - -static void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu_page *page, *npage; - - list_for_each_entry_safe(page, npage, &vcpu->kvm->active_mmu_pages, - link) { - if (page->global) - continue; - - if (!page->parent_pte) - continue; - - *page->parent_pte = 0; - release_pt_page_64(vcpu, page->page_hpa, 1); - } - ++kvm_stat.tlb_flush; - kvm_arch_ops->tlb_flush(vcpu); -} - -static void paging_new_cr3(struct kvm_vcpu *vcpu) -{ - kvm_mmu_flush_tlb(vcpu); -} - -static void mark_pagetable_nonglobal(void *shadow_pte) -{ - page_header(__pa(shadow_pte))->global = 0; -} - -static inline void set_pte_common(struct kvm_vcpu *vcpu, - u64 *shadow_pte, - gpa_t gaddr, - int dirty, - u64 access_bits) -{ - hpa_t paddr; - - *shadow_pte |= access_bits << PT_SHADOW_BITS_OFFSET; - if (!dirty) - access_bits &= ~PT_WRITABLE_MASK; - - if (access_bits & PT_WRITABLE_MASK) - mark_page_dirty(vcpu->kvm, gaddr >> PAGE_SHIFT); - - *shadow_pte |= access_bits; - - paddr = gpa_to_hpa(vcpu, gaddr & PT64_BASE_ADDR_MASK); - - if (!(*shadow_pte & PT_GLOBAL_MASK)) - mark_pagetable_nonglobal(shadow_pte); - - if (is_error_hpa(paddr)) { - *shadow_pte |= gaddr; - *shadow_pte |= PT_SHADOW_IO_MARK; - *shadow_pte &= ~PT_PRESENT_MASK; - } else { - *shadow_pte |= paddr; - page_header_update_slot(vcpu->kvm, shadow_pte, gaddr); - } -} - -static void inject_page_fault(struct kvm_vcpu *vcpu, - u64 addr, - u32 err_code) -{ - kvm_arch_ops->inject_page_fault(vcpu, addr, err_code); -} - -static inline int fix_read_pf(u64 *shadow_ent) -{ - if ((*shadow_ent & PT_SHADOW_USER_MASK) && - !(*shadow_ent & PT_USER_MASK)) { - /* - * If supervisor write protect is disabled, we shadow kernel - * pages as user pages so we can trap the write access. - */ - *shadow_ent |= PT_USER_MASK; - *shadow_ent &= ~PT_WRITABLE_MASK; - - return 1; - - } - return 0; -} - -static int may_access(u64 pte, int write, int user) -{ - - if (user && !(pte & PT_USER_MASK)) - return 0; - if (write && !(pte & PT_WRITABLE_MASK)) - return 0; - return 1; -} - -/* - * Remove a shadow pte. - */ -static void paging_inval_page(struct kvm_vcpu *vcpu, gva_t addr) -{ - hpa_t page_addr = vcpu->mmu.root_hpa; - int level = vcpu->mmu.shadow_root_level; - - ++kvm_stat.invlpg; - - for (; ; level--) { - u32 index = PT64_INDEX(addr, level); - u64 *table = __va(page_addr); - - if (level == PT_PAGE_TABLE_LEVEL ) { - table[index] = 0; - return; - } - - if (!is_present_pte(table[index])) - return; - - page_addr = table[index] & PT64_BASE_ADDR_MASK; - - if (level == PT_DIRECTORY_LEVEL && - (table[index] & PT_SHADOW_PS_MARK)) { - table[index] = 0; - release_pt_page_64(vcpu, page_addr, PT_PAGE_TABLE_LEVEL); - - kvm_arch_ops->tlb_flush(vcpu); - return; - } - } -} - -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(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu *context = &vcpu->mmu; - - ASSERT(is_pae(vcpu)); - context->new_cr3 = paging_new_cr3; - context->page_fault = paging64_page_fault; - context->inval_page = paging_inval_page; - context->gva_to_gpa = paging64_gva_to_gpa; - context->free = paging_free; - context->root_level = PT64_ROOT_LEVEL; - context->shadow_root_level = PT64_ROOT_LEVEL; - context->root_hpa = kvm_mmu_alloc_page(vcpu, NULL); - ASSERT(VALID_PAGE(context->root_hpa)); - kvm_arch_ops->set_cr3(vcpu, context->root_hpa | - (vcpu->cr3 & (CR3_PCD_MASK | CR3_WPT_MASK))); - return 0; -} - -static int paging32_init_context(struct kvm_vcpu *vcpu) -{ - struct kvm_mmu *context = &vcpu->mmu; - - context->new_cr3 = paging_new_cr3; - context->page_fault = paging32_page_fault; - context->inval_page = paging_inval_page; - context->gva_to_gpa = paging32_gva_to_gpa; - context->free = paging_free; - context->root_level = PT32_ROOT_LEVEL; - context->shadow_root_level = PT32E_ROOT_LEVEL; - context->root_hpa = kvm_mmu_alloc_page(vcpu, NULL); - ASSERT(VALID_PAGE(context->root_hpa)); - kvm_arch_ops->set_cr3(vcpu, context->root_hpa | - (vcpu->cr3 & (CR3_PCD_MASK | CR3_WPT_MASK))); - return 0; -} - -static int paging32E_init_context(struct kvm_vcpu *vcpu) -{ - int ret; - - if ((ret = paging64_init_context(vcpu))) - return ret; - - vcpu->mmu.root_level = PT32E_ROOT_LEVEL; - vcpu->mmu.shadow_root_level = PT32E_ROOT_LEVEL; - return 0; -} - -static int init_kvm_mmu(struct kvm_vcpu *vcpu) -{ - ASSERT(vcpu); - ASSERT(!VALID_PAGE(vcpu->mmu.root_hpa)); - - if (!is_paging(vcpu)) - return nonpaging_init_context(vcpu); - else if (kvm_arch_ops->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->mmu.root_hpa)) { - vcpu->mmu.free(vcpu); - vcpu->mmu.root_hpa = INVALID_PAGE; - } -} - -int kvm_mmu_reset_context(struct kvm_vcpu *vcpu) -{ - destroy_kvm_mmu(vcpu); - return init_kvm_mmu(vcpu); -} - -static void free_mmu_pages(struct kvm_vcpu *vcpu) -{ - while (!list_empty(&vcpu->free_pages)) { - struct kvm_mmu_page *page; - - page = list_entry(vcpu->free_pages.next, - struct kvm_mmu_page, link); - list_del(&page->link); - __free_page(pfn_to_page(page->page_hpa >> PAGE_SHIFT)); - page->page_hpa = INVALID_PAGE; - } -} - -static int alloc_mmu_pages(struct kvm_vcpu *vcpu) -{ - int i; - - ASSERT(vcpu); - - for (i = 0; i < KVM_NUM_MMU_PAGES; i++) { - struct page *page; - struct kvm_mmu_page *page_header = &vcpu->page_header_buf[i]; - - INIT_LIST_HEAD(&page_header->link); - if ((page = alloc_page(GFP_KVM_MMU)) == NULL) - goto error_1; - page->private = (unsigned long)page_header; - page_header->page_hpa = (hpa_t)page_to_pfn(page) << PAGE_SHIFT; - memset(__va(page_header->page_hpa), 0, PAGE_SIZE); - list_add(&page_header->link, &vcpu->free_pages); - } - return 0; - -error_1: - free_mmu_pages(vcpu); - return -ENOMEM; -} - -int kvm_mmu_init(struct kvm_vcpu *vcpu) -{ - int r; - - ASSERT(vcpu); - ASSERT(!VALID_PAGE(vcpu->mmu.root_hpa)); - ASSERT(list_empty(&vcpu->free_pages)); - - if ((r = alloc_mmu_pages(vcpu))) - return r; - - if ((r = init_kvm_mmu(vcpu))) { - free_mmu_pages(vcpu); - return r; - } - return 0; -} - -void kvm_mmu_destroy(struct kvm_vcpu *vcpu) -{ - ASSERT(vcpu); - - destroy_kvm_mmu(vcpu); - free_mmu_pages(vcpu); -} - -void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) -{ - struct kvm_mmu_page *page; - - list_for_each_entry(page, &kvm->active_mmu_pages, link) { - int i; - u64 *pt; - - if (!test_bit(slot, &page->slot_bitmap)) - continue; - - pt = __va(page->page_hpa); - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) - /* avoid RMW */ - if (pt[i] & PT_WRITABLE_MASK) - pt[i] &= ~PT_WRITABLE_MASK; - - } -} |