diff options
Diffstat (limited to 'drivers/kvm/paging_tmpl.h')
-rw-r--r-- | drivers/kvm/paging_tmpl.h | 511 |
1 files changed, 0 insertions, 511 deletions
diff --git a/drivers/kvm/paging_tmpl.h b/drivers/kvm/paging_tmpl.h deleted file mode 100644 index 6b094b44f8f..00000000000 --- a/drivers/kvm/paging_tmpl.h +++ /dev/null @@ -1,511 +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. - * - */ - -/* - * We need the mmu code to access both 32-bit and 64-bit guest ptes, - * so the code in this file is compiled twice, once per pte size. - */ - -#if PTTYPE == 64 - #define pt_element_t u64 - #define guest_walker guest_walker64 - #define FNAME(name) paging##64_##name - #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK - #define PT_DIR_BASE_ADDR_MASK PT64_DIR_BASE_ADDR_MASK - #define PT_INDEX(addr, level) PT64_INDEX(addr, level) - #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level) - #define PT_LEVEL_MASK(level) PT64_LEVEL_MASK(level) - #ifdef CONFIG_X86_64 - #define PT_MAX_FULL_LEVELS 4 - #else - #define PT_MAX_FULL_LEVELS 2 - #endif -#elif PTTYPE == 32 - #define pt_element_t u32 - #define guest_walker guest_walker32 - #define FNAME(name) paging##32_##name - #define PT_BASE_ADDR_MASK PT32_BASE_ADDR_MASK - #define PT_DIR_BASE_ADDR_MASK PT32_DIR_BASE_ADDR_MASK - #define PT_INDEX(addr, level) PT32_INDEX(addr, level) - #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level) - #define PT_LEVEL_MASK(level) PT32_LEVEL_MASK(level) - #define PT_MAX_FULL_LEVELS 2 -#else - #error Invalid PTTYPE value -#endif - -/* - * The guest_walker structure emulates the behavior of the hardware page - * table walker. - */ -struct guest_walker { - int level; - gfn_t table_gfn[PT_MAX_FULL_LEVELS]; - pt_element_t *table; - pt_element_t pte; - pt_element_t *ptep; - struct page *page; - int index; - pt_element_t inherited_ar; - gfn_t gfn; - u32 error_code; -}; - -/* - * Fetch a guest pte for a guest virtual address - */ -static int FNAME(walk_addr)(struct guest_walker *walker, - struct kvm_vcpu *vcpu, gva_t addr, - int write_fault, int user_fault, int fetch_fault) -{ - hpa_t hpa; - struct kvm_memory_slot *slot; - pt_element_t *ptep; - pt_element_t root; - gfn_t table_gfn; - - pgprintk("%s: addr %lx\n", __FUNCTION__, addr); - walker->level = vcpu->mmu.root_level; - walker->table = NULL; - walker->page = NULL; - walker->ptep = NULL; - root = vcpu->cr3; -#if PTTYPE == 64 - if (!is_long_mode(vcpu)) { - walker->ptep = &vcpu->pdptrs[(addr >> 30) & 3]; - root = *walker->ptep; - walker->pte = root; - if (!(root & PT_PRESENT_MASK)) - goto not_present; - --walker->level; - } -#endif - table_gfn = (root & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; - walker->table_gfn[walker->level - 1] = table_gfn; - pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__, - walker->level - 1, table_gfn); - slot = gfn_to_memslot(vcpu->kvm, table_gfn); - hpa = safe_gpa_to_hpa(vcpu, root & PT64_BASE_ADDR_MASK); - walker->page = pfn_to_page(hpa >> PAGE_SHIFT); - walker->table = kmap_atomic(walker->page, KM_USER0); - - ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) || - (vcpu->cr3 & CR3_NONPAE_RESERVED_BITS) == 0); - - walker->inherited_ar = PT_USER_MASK | PT_WRITABLE_MASK; - - for (;;) { - int index = PT_INDEX(addr, walker->level); - hpa_t paddr; - - ptep = &walker->table[index]; - walker->index = index; - ASSERT(((unsigned long)walker->table & PAGE_MASK) == - ((unsigned long)ptep & PAGE_MASK)); - - if (!is_present_pte(*ptep)) - goto not_present; - - if (write_fault && !is_writeble_pte(*ptep)) - if (user_fault || is_write_protection(vcpu)) - goto access_error; - - if (user_fault && !(*ptep & PT_USER_MASK)) - goto access_error; - -#if PTTYPE == 64 - if (fetch_fault && is_nx(vcpu) && (*ptep & PT64_NX_MASK)) - goto access_error; -#endif - - if (!(*ptep & PT_ACCESSED_MASK)) { - mark_page_dirty(vcpu->kvm, table_gfn); - *ptep |= PT_ACCESSED_MASK; - } - - if (walker->level == PT_PAGE_TABLE_LEVEL) { - walker->gfn = (*ptep & PT_BASE_ADDR_MASK) - >> PAGE_SHIFT; - break; - } - - if (walker->level == PT_DIRECTORY_LEVEL - && (*ptep & PT_PAGE_SIZE_MASK) - && (PTTYPE == 64 || is_pse(vcpu))) { - walker->gfn = (*ptep & PT_DIR_BASE_ADDR_MASK) - >> PAGE_SHIFT; - walker->gfn += PT_INDEX(addr, PT_PAGE_TABLE_LEVEL); - break; - } - - walker->inherited_ar &= walker->table[index]; - table_gfn = (*ptep & PT_BASE_ADDR_MASK) >> PAGE_SHIFT; - kunmap_atomic(walker->table, KM_USER0); - paddr = safe_gpa_to_hpa(vcpu, table_gfn << PAGE_SHIFT); - walker->page = pfn_to_page(paddr >> PAGE_SHIFT); - walker->table = kmap_atomic(walker->page, KM_USER0); - --walker->level; - walker->table_gfn[walker->level - 1 ] = table_gfn; - pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__, - walker->level - 1, table_gfn); - } - walker->pte = *ptep; - if (walker->page) - walker->ptep = NULL; - if (walker->table) - kunmap_atomic(walker->table, KM_USER0); - pgprintk("%s: pte %llx\n", __FUNCTION__, (u64)*ptep); - return 1; - -not_present: - walker->error_code = 0; - goto err; - -access_error: - walker->error_code = PFERR_PRESENT_MASK; - -err: - if (write_fault) - walker->error_code |= PFERR_WRITE_MASK; - if (user_fault) - walker->error_code |= PFERR_USER_MASK; - if (fetch_fault) - walker->error_code |= PFERR_FETCH_MASK; - if (walker->table) - kunmap_atomic(walker->table, KM_USER0); - return 0; -} - -static void FNAME(mark_pagetable_dirty)(struct kvm *kvm, - struct guest_walker *walker) -{ - mark_page_dirty(kvm, walker->table_gfn[walker->level - 1]); -} - -static void FNAME(set_pte_common)(struct kvm_vcpu *vcpu, - u64 *shadow_pte, - gpa_t gaddr, - pt_element_t gpte, - u64 access_bits, - int user_fault, - int write_fault, - int *ptwrite, - struct guest_walker *walker, - gfn_t gfn) -{ - hpa_t paddr; - int dirty = gpte & PT_DIRTY_MASK; - u64 spte = *shadow_pte; - int was_rmapped = is_rmap_pte(spte); - - pgprintk("%s: spte %llx gpte %llx access %llx write_fault %d" - " user_fault %d gfn %lx\n", - __FUNCTION__, spte, (u64)gpte, access_bits, - write_fault, user_fault, gfn); - - if (write_fault && !dirty) { - pt_element_t *guest_ent, *tmp = NULL; - - if (walker->ptep) - guest_ent = walker->ptep; - else { - tmp = kmap_atomic(walker->page, KM_USER0); - guest_ent = &tmp[walker->index]; - } - - *guest_ent |= PT_DIRTY_MASK; - if (!walker->ptep) - kunmap_atomic(tmp, KM_USER0); - dirty = 1; - FNAME(mark_pagetable_dirty)(vcpu->kvm, walker); - } - - spte |= PT_PRESENT_MASK | PT_ACCESSED_MASK | PT_DIRTY_MASK; - spte |= gpte & PT64_NX_MASK; - if (!dirty) - access_bits &= ~PT_WRITABLE_MASK; - - paddr = gpa_to_hpa(vcpu, gaddr & PT64_BASE_ADDR_MASK); - - spte |= PT_PRESENT_MASK; - if (access_bits & PT_USER_MASK) - spte |= PT_USER_MASK; - - if (is_error_hpa(paddr)) { - spte |= gaddr; - spte |= PT_SHADOW_IO_MARK; - spte &= ~PT_PRESENT_MASK; - set_shadow_pte(shadow_pte, spte); - return; - } - - spte |= paddr; - - if ((access_bits & PT_WRITABLE_MASK) - || (write_fault && !is_write_protection(vcpu) && !user_fault)) { - struct kvm_mmu_page *shadow; - - spte |= PT_WRITABLE_MASK; - if (user_fault) { - mmu_unshadow(vcpu, gfn); - goto unshadowed; - } - - shadow = kvm_mmu_lookup_page(vcpu, gfn); - if (shadow) { - pgprintk("%s: found shadow page for %lx, marking ro\n", - __FUNCTION__, gfn); - access_bits &= ~PT_WRITABLE_MASK; - if (is_writeble_pte(spte)) { - spte &= ~PT_WRITABLE_MASK; - kvm_x86_ops->tlb_flush(vcpu); - } - if (write_fault) - *ptwrite = 1; - } - } - -unshadowed: - - if (access_bits & PT_WRITABLE_MASK) - mark_page_dirty(vcpu->kvm, gaddr >> PAGE_SHIFT); - - set_shadow_pte(shadow_pte, spte); - page_header_update_slot(vcpu->kvm, shadow_pte, gaddr); - if (!was_rmapped) - rmap_add(vcpu, shadow_pte); -} - -static void FNAME(set_pte)(struct kvm_vcpu *vcpu, pt_element_t gpte, - u64 *shadow_pte, u64 access_bits, - int user_fault, int write_fault, int *ptwrite, - struct guest_walker *walker, gfn_t gfn) -{ - access_bits &= gpte; - FNAME(set_pte_common)(vcpu, shadow_pte, gpte & PT_BASE_ADDR_MASK, - gpte, access_bits, user_fault, write_fault, - ptwrite, walker, gfn); -} - -static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page, - u64 *spte, const void *pte, int bytes) -{ - pt_element_t gpte; - - if (bytes < sizeof(pt_element_t)) - return; - gpte = *(const pt_element_t *)pte; - if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) - return; - pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte, spte); - FNAME(set_pte)(vcpu, gpte, spte, PT_USER_MASK | PT_WRITABLE_MASK, 0, - 0, NULL, NULL, - (gpte & PT_BASE_ADDR_MASK) >> PAGE_SHIFT); -} - -static void FNAME(set_pde)(struct kvm_vcpu *vcpu, pt_element_t gpde, - u64 *shadow_pte, u64 access_bits, - int user_fault, int write_fault, int *ptwrite, - struct guest_walker *walker, gfn_t gfn) -{ - gpa_t gaddr; - - access_bits &= gpde; - gaddr = (gpa_t)gfn << PAGE_SHIFT; - if (PTTYPE == 32 && is_cpuid_PSE36()) - gaddr |= (gpde & PT32_DIR_PSE36_MASK) << - (32 - PT32_DIR_PSE36_SHIFT); - FNAME(set_pte_common)(vcpu, shadow_pte, gaddr, - gpde, access_bits, user_fault, write_fault, - ptwrite, walker, gfn); -} - -/* - * Fetch a shadow pte for a specific level in the paging hierarchy. - */ -static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, - struct guest_walker *walker, - int user_fault, int write_fault, int *ptwrite) -{ - hpa_t shadow_addr; - int level; - u64 *shadow_ent; - u64 *prev_shadow_ent = NULL; - - if (!is_present_pte(walker->pte)) - return NULL; - - shadow_addr = vcpu->mmu.root_hpa; - level = vcpu->mmu.shadow_root_level; - if (level == PT32E_ROOT_LEVEL) { - shadow_addr = vcpu->mmu.pae_root[(addr >> 30) & 3]; - shadow_addr &= PT64_BASE_ADDR_MASK; - --level; - } - - for (; ; level--) { - u32 index = SHADOW_PT_INDEX(addr, level); - struct kvm_mmu_page *shadow_page; - u64 shadow_pte; - int metaphysical; - gfn_t table_gfn; - unsigned hugepage_access = 0; - - shadow_ent = ((u64 *)__va(shadow_addr)) + index; - if (is_present_pte(*shadow_ent) || is_io_pte(*shadow_ent)) { - if (level == PT_PAGE_TABLE_LEVEL) - break; - shadow_addr = *shadow_ent & PT64_BASE_ADDR_MASK; - prev_shadow_ent = shadow_ent; - continue; - } - - if (level == PT_PAGE_TABLE_LEVEL) - break; - - if (level - 1 == PT_PAGE_TABLE_LEVEL - && walker->level == PT_DIRECTORY_LEVEL) { - metaphysical = 1; - hugepage_access = walker->pte; - hugepage_access &= PT_USER_MASK | PT_WRITABLE_MASK; - if (walker->pte & PT64_NX_MASK) - hugepage_access |= (1 << 2); - hugepage_access >>= PT_WRITABLE_SHIFT; - table_gfn = (walker->pte & PT_BASE_ADDR_MASK) - >> PAGE_SHIFT; - } else { - metaphysical = 0; - table_gfn = walker->table_gfn[level - 2]; - } - shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1, - metaphysical, hugepage_access, - shadow_ent); - shadow_addr = __pa(shadow_page->spt); - shadow_pte = shadow_addr | PT_PRESENT_MASK | PT_ACCESSED_MASK - | PT_WRITABLE_MASK | PT_USER_MASK; - *shadow_ent = shadow_pte; - prev_shadow_ent = shadow_ent; - } - - if (walker->level == PT_DIRECTORY_LEVEL) { - FNAME(set_pde)(vcpu, walker->pte, shadow_ent, - walker->inherited_ar, user_fault, write_fault, - ptwrite, walker, walker->gfn); - } else { - ASSERT(walker->level == PT_PAGE_TABLE_LEVEL); - FNAME(set_pte)(vcpu, walker->pte, shadow_ent, - walker->inherited_ar, user_fault, write_fault, - ptwrite, walker, walker->gfn); - } - return shadow_ent; -} - -/* - * Page fault handler. There are several causes for a page fault: - * - there is no shadow pte for the guest pte - * - write access through a shadow pte marked read only so that we can set - * the dirty bit - * - write access to a shadow pte marked read only so we can update the page - * dirty bitmap, when userspace requests it - * - mmio access; in this case we will never install a present shadow pte - * - normal guest page fault due to the guest pte marked not present, not - * writable, or not executable - * - * Returns: 1 if we need to emulate the instruction, 0 otherwise, or - * a negative value on error. - */ -static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, - u32 error_code) -{ - int write_fault = error_code & PFERR_WRITE_MASK; - int user_fault = error_code & PFERR_USER_MASK; - int fetch_fault = error_code & PFERR_FETCH_MASK; - struct guest_walker walker; - u64 *shadow_pte; - int write_pt = 0; - int r; - - pgprintk("%s: addr %lx err %x\n", __FUNCTION__, addr, error_code); - kvm_mmu_audit(vcpu, "pre page fault"); - - r = mmu_topup_memory_caches(vcpu); - if (r) - return r; - - /* - * Look up the shadow pte for the faulting address. - */ - r = FNAME(walk_addr)(&walker, vcpu, addr, write_fault, user_fault, - fetch_fault); - - /* - * The page is not mapped by the guest. Let the guest handle it. - */ - if (!r) { - pgprintk("%s: guest page fault\n", __FUNCTION__); - inject_page_fault(vcpu, addr, walker.error_code); - vcpu->last_pt_write_count = 0; /* reset fork detector */ - return 0; - } - - shadow_pte = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, - &write_pt); - pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __FUNCTION__, - shadow_pte, *shadow_pte, write_pt); - - if (!write_pt) - vcpu->last_pt_write_count = 0; /* reset fork detector */ - - /* - * mmio: emulate if accessible, otherwise its a guest fault. - */ - if (is_io_pte(*shadow_pte)) - return 1; - - ++vcpu->stat.pf_fixed; - kvm_mmu_audit(vcpu, "post page fault (fixed)"); - - return write_pt; -} - -static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr) -{ - struct guest_walker walker; - gpa_t gpa = UNMAPPED_GVA; - int r; - - r = FNAME(walk_addr)(&walker, vcpu, vaddr, 0, 0, 0); - - if (r) { - gpa = (gpa_t)walker.gfn << PAGE_SHIFT; - gpa |= vaddr & ~PAGE_MASK; - } - - return gpa; -} - -#undef pt_element_t -#undef guest_walker -#undef FNAME -#undef PT_BASE_ADDR_MASK -#undef PT_INDEX -#undef SHADOW_PT_INDEX -#undef PT_LEVEL_MASK -#undef PT_DIR_BASE_ADDR_MASK -#undef PT_MAX_FULL_LEVELS |