Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Kernel-based Virtual Machine driver for Linux |
| 3 | * |
| 4 | * This module enables machines with Intel VT-x extensions to run virtual |
| 5 | * machines without emulation or binary translation. |
| 6 | * |
| 7 | * MMU support |
| 8 | * |
| 9 | * Copyright (C) 2006 Qumranet, Inc. |
Nicolas Kaiser | 9611c18 | 2010-10-06 14:23:22 +0200 | [diff] [blame] | 10 | * Copyright 2010 Red Hat, Inc. and/or its affiliates. |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 11 | * |
| 12 | * Authors: |
| 13 | * Yaniv Kamay <yaniv@qumranet.com> |
| 14 | * Avi Kivity <avi@qumranet.com> |
| 15 | * |
| 16 | * This work is licensed under the terms of the GNU GPL, version 2. See |
| 17 | * the COPYING file in the top-level directory. |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | * We need the mmu code to access both 32-bit and 64-bit guest ptes, |
| 23 | * so the code in this file is compiled twice, once per pte size. |
| 24 | */ |
| 25 | |
| 26 | #if PTTYPE == 64 |
| 27 | #define pt_element_t u64 |
| 28 | #define guest_walker guest_walker64 |
| 29 | #define FNAME(name) paging##64_##name |
| 30 | #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 31 | #define PT_LVL_ADDR_MASK(lvl) PT64_LVL_ADDR_MASK(lvl) |
| 32 | #define PT_LVL_OFFSET_MASK(lvl) PT64_LVL_OFFSET_MASK(lvl) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 33 | #define PT_INDEX(addr, level) PT64_INDEX(addr, level) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 34 | #define PT_LEVEL_MASK(level) PT64_LEVEL_MASK(level) |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 35 | #define PT_LEVEL_BITS PT64_LEVEL_BITS |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 36 | #ifdef CONFIG_X86_64 |
| 37 | #define PT_MAX_FULL_LEVELS 4 |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 38 | #define CMPXCHG cmpxchg |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 39 | #else |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 40 | #define CMPXCHG cmpxchg64 |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 41 | #define PT_MAX_FULL_LEVELS 2 |
| 42 | #endif |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 43 | #elif PTTYPE == 32 |
| 44 | #define pt_element_t u32 |
| 45 | #define guest_walker guest_walker32 |
| 46 | #define FNAME(name) paging##32_##name |
| 47 | #define PT_BASE_ADDR_MASK PT32_BASE_ADDR_MASK |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 48 | #define PT_LVL_ADDR_MASK(lvl) PT32_LVL_ADDR_MASK(lvl) |
| 49 | #define PT_LVL_OFFSET_MASK(lvl) PT32_LVL_OFFSET_MASK(lvl) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 50 | #define PT_INDEX(addr, level) PT32_INDEX(addr, level) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 51 | #define PT_LEVEL_MASK(level) PT32_LEVEL_MASK(level) |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 52 | #define PT_LEVEL_BITS PT32_LEVEL_BITS |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 53 | #define PT_MAX_FULL_LEVELS 2 |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 54 | #define CMPXCHG cmpxchg |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 55 | #else |
| 56 | #error Invalid PTTYPE value |
| 57 | #endif |
| 58 | |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 59 | #define gpte_to_gfn_lvl FNAME(gpte_to_gfn_lvl) |
| 60 | #define gpte_to_gfn(pte) gpte_to_gfn_lvl((pte), PT_PAGE_TABLE_LEVEL) |
Avi Kivity | 5fb07dd | 2007-11-21 12:35:07 +0200 | [diff] [blame] | 61 | |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 62 | /* |
| 63 | * The guest_walker structure emulates the behavior of the hardware page |
| 64 | * table walker. |
| 65 | */ |
| 66 | struct guest_walker { |
| 67 | int level; |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 68 | gfn_t table_gfn[PT_MAX_FULL_LEVELS]; |
Marcelo Tosatti | 7819026 | 2007-12-11 19:12:27 -0500 | [diff] [blame] | 69 | pt_element_t ptes[PT_MAX_FULL_LEVELS]; |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 70 | pt_element_t prefetch_ptes[PTE_PREFETCH_NUM]; |
Marcelo Tosatti | 7819026 | 2007-12-11 19:12:27 -0500 | [diff] [blame] | 71 | gpa_t pte_gpa[PT_MAX_FULL_LEVELS]; |
Avi Kivity | fe135d2 | 2007-12-09 16:15:46 +0200 | [diff] [blame] | 72 | unsigned pt_access; |
| 73 | unsigned pte_access; |
Avi Kivity | 815af8d | 2007-01-05 16:36:44 -0800 | [diff] [blame] | 74 | gfn_t gfn; |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 75 | struct x86_exception fault; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 76 | }; |
| 77 | |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 78 | static gfn_t gpte_to_gfn_lvl(pt_element_t gpte, int lvl) |
Avi Kivity | 5fb07dd | 2007-11-21 12:35:07 +0200 | [diff] [blame] | 79 | { |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 80 | return (gpte & PT_LVL_ADDR_MASK(lvl)) >> PAGE_SHIFT; |
Avi Kivity | 5fb07dd | 2007-11-21 12:35:07 +0200 | [diff] [blame] | 81 | } |
| 82 | |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 83 | static bool FNAME(cmpxchg_gpte)(struct kvm *kvm, |
| 84 | gfn_t table_gfn, unsigned index, |
| 85 | pt_element_t orig_pte, pt_element_t new_pte) |
| 86 | { |
| 87 | pt_element_t ret; |
| 88 | pt_element_t *table; |
| 89 | struct page *page; |
| 90 | |
| 91 | page = gfn_to_page(kvm, table_gfn); |
Izik Eidus | 72dc67a | 2008-02-10 18:04:15 +0200 | [diff] [blame] | 92 | |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 93 | table = kmap_atomic(page, KM_USER0); |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 94 | ret = CMPXCHG(&table[index], orig_pte, new_pte); |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 95 | kunmap_atomic(table, KM_USER0); |
| 96 | |
| 97 | kvm_release_page_dirty(page); |
| 98 | |
| 99 | return (ret != orig_pte); |
| 100 | } |
| 101 | |
Avi Kivity | bedbe4e | 2007-12-09 16:52:56 +0200 | [diff] [blame] | 102 | static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte) |
| 103 | { |
| 104 | unsigned access; |
| 105 | |
| 106 | access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK; |
| 107 | #if PTTYPE == 64 |
Joerg Roedel | 2d48a98 | 2010-09-10 17:31:01 +0200 | [diff] [blame] | 108 | if (vcpu->arch.mmu.nx) |
Avi Kivity | bedbe4e | 2007-12-09 16:52:56 +0200 | [diff] [blame] | 109 | access &= ~(gpte >> PT64_NX_SHIFT); |
| 110 | #endif |
| 111 | return access; |
| 112 | } |
| 113 | |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 114 | /* |
| 115 | * Fetch a guest pte for a guest virtual address |
| 116 | */ |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 117 | static int FNAME(walk_addr_generic)(struct guest_walker *walker, |
| 118 | struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 119 | gva_t addr, u32 access) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 120 | { |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 121 | pt_element_t pte; |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 122 | gfn_t table_gfn; |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 123 | unsigned index, pt_access, uninitialized_var(pte_access); |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 124 | gpa_t pte_gpa; |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 125 | bool eperm, present, rsvd_fault; |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 126 | int offset, write_fault, user_fault, fetch_fault; |
| 127 | |
| 128 | write_fault = access & PFERR_WRITE_MASK; |
| 129 | user_fault = access & PFERR_USER_MASK; |
| 130 | fetch_fault = access & PFERR_FETCH_MASK; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 131 | |
Avi Kivity | 0742017 | 2009-07-06 12:21:32 +0300 | [diff] [blame] | 132 | trace_kvm_mmu_pagetable_walk(addr, write_fault, user_fault, |
| 133 | fetch_fault); |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 134 | walk: |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 135 | present = true; |
| 136 | eperm = rsvd_fault = false; |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 137 | walker->level = mmu->root_level; |
| 138 | pte = mmu->get_cr3(vcpu); |
| 139 | |
Avi Kivity | 1b0973b | 2007-01-05 16:36:41 -0800 | [diff] [blame] | 140 | #if PTTYPE == 64 |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 141 | if (walker->level == PT32E_ROOT_LEVEL) { |
Joerg Roedel | d41d189 | 2010-09-10 17:30:58 +0200 | [diff] [blame] | 142 | pte = kvm_pdptr_read_mmu(vcpu, mmu, (addr >> 30) & 3); |
Avi Kivity | 0742017 | 2009-07-06 12:21:32 +0300 | [diff] [blame] | 143 | trace_kvm_mmu_paging_element(pte, walker->level); |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 144 | if (!is_present_gpte(pte)) { |
| 145 | present = false; |
| 146 | goto error; |
| 147 | } |
Avi Kivity | 1b0973b | 2007-01-05 16:36:41 -0800 | [diff] [blame] | 148 | --walker->level; |
| 149 | } |
| 150 | #endif |
Avi Kivity | a9058ec | 2006-12-29 16:49:37 -0800 | [diff] [blame] | 151 | ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) || |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 152 | (mmu->get_cr3(vcpu) & CR3_NONPAE_RESERVED_BITS) == 0); |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 153 | |
Avi Kivity | fe135d2 | 2007-12-09 16:15:46 +0200 | [diff] [blame] | 154 | pt_access = ACC_ALL; |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 155 | |
| 156 | for (;;) { |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 157 | index = PT_INDEX(addr, walker->level); |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 158 | |
Avi Kivity | 5fb07dd | 2007-11-21 12:35:07 +0200 | [diff] [blame] | 159 | table_gfn = gpte_to_gfn(pte); |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 160 | offset = index * sizeof(pt_element_t); |
| 161 | pte_gpa = gfn_to_gpa(table_gfn) + offset; |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 162 | walker->table_gfn[walker->level - 1] = table_gfn; |
Marcelo Tosatti | 7819026 | 2007-12-11 19:12:27 -0500 | [diff] [blame] | 163 | walker->pte_gpa[walker->level - 1] = pte_gpa; |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 164 | |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 165 | if (kvm_read_guest_page_mmu(vcpu, mmu, table_gfn, &pte, |
| 166 | offset, sizeof(pte), |
| 167 | PFERR_USER_MASK|PFERR_WRITE_MASK)) { |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 168 | present = false; |
| 169 | break; |
| 170 | } |
Marcelo Tosatti | a6085fba | 2010-01-14 17:41:27 -0200 | [diff] [blame] | 171 | |
Avi Kivity | 0742017 | 2009-07-06 12:21:32 +0300 | [diff] [blame] | 172 | trace_kvm_mmu_paging_element(pte, walker->level); |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 173 | |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 174 | if (!is_present_gpte(pte)) { |
| 175 | present = false; |
| 176 | break; |
| 177 | } |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 178 | |
Joerg Roedel | 3241f22 | 2010-09-10 17:30:45 +0200 | [diff] [blame] | 179 | if (is_rsvd_bits_set(&vcpu->arch.mmu, pte, walker->level)) { |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 180 | rsvd_fault = true; |
| 181 | break; |
| 182 | } |
Dong, Eddie | 82725b2 | 2009-03-30 16:21:08 +0800 | [diff] [blame] | 183 | |
Takuya Yoshikawa | 8dae444 | 2010-01-18 18:45:10 +0900 | [diff] [blame] | 184 | if (write_fault && !is_writable_pte(pte)) |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 185 | if (user_fault || is_write_protection(vcpu)) |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 186 | eperm = true; |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 187 | |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 188 | if (user_fault && !(pte & PT_USER_MASK)) |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 189 | eperm = true; |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 190 | |
Avi Kivity | 73b1087 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 191 | #if PTTYPE == 64 |
Xiao Guangrong | 24222c2 | 2010-04-06 18:31:13 +0800 | [diff] [blame] | 192 | if (fetch_fault && (pte & PT64_NX_MASK)) |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 193 | eperm = true; |
Avi Kivity | 73b1087 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 194 | #endif |
| 195 | |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 196 | if (!eperm && !rsvd_fault && !(pte & PT_ACCESSED_MASK)) { |
Avi Kivity | 0742017 | 2009-07-06 12:21:32 +0300 | [diff] [blame] | 197 | trace_kvm_mmu_set_accessed_bit(table_gfn, index, |
| 198 | sizeof(pte)); |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 199 | if (FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, |
| 200 | index, pte, pte|PT_ACCESSED_MASK)) |
| 201 | goto walk; |
Gui Jianfeng | f3b8c96 | 2010-05-05 09:09:21 +0800 | [diff] [blame] | 202 | mark_page_dirty(vcpu->kvm, table_gfn); |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 203 | pte |= PT_ACCESSED_MASK; |
Avi Kivity | bf3f8e8 | 2007-02-19 14:37:46 +0200 | [diff] [blame] | 204 | } |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 205 | |
Avi Kivity | bedbe4e | 2007-12-09 16:52:56 +0200 | [diff] [blame] | 206 | pte_access = pt_access & FNAME(gpte_access)(vcpu, pte); |
Avi Kivity | fe135d2 | 2007-12-09 16:15:46 +0200 | [diff] [blame] | 207 | |
Marcelo Tosatti | 7819026 | 2007-12-11 19:12:27 -0500 | [diff] [blame] | 208 | walker->ptes[walker->level - 1] = pte; |
| 209 | |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 210 | if ((walker->level == PT_PAGE_TABLE_LEVEL) || |
| 211 | ((walker->level == PT_DIRECTORY_LEVEL) && |
Gui Jianfeng | 814a59d | 2010-04-16 17:18:01 +0800 | [diff] [blame] | 212 | is_large_pte(pte) && |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 213 | (PTTYPE == 64 || is_pse(vcpu))) || |
| 214 | ((walker->level == PT_PDPE_LEVEL) && |
Gui Jianfeng | 814a59d | 2010-04-16 17:18:01 +0800 | [diff] [blame] | 215 | is_large_pte(pte) && |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 216 | mmu->root_level == PT64_ROOT_LEVEL)) { |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 217 | int lvl = walker->level; |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 218 | gpa_t real_gpa; |
| 219 | gfn_t gfn; |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 220 | u32 ac; |
Avi Kivity | 815af8d | 2007-01-05 16:36:44 -0800 | [diff] [blame] | 221 | |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 222 | gfn = gpte_to_gfn_lvl(pte, lvl); |
| 223 | gfn += (addr & PT_LVL_OFFSET_MASK(lvl)) >> PAGE_SHIFT; |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 224 | |
| 225 | if (PTTYPE == 32 && |
| 226 | walker->level == PT_DIRECTORY_LEVEL && |
| 227 | is_cpuid_PSE36()) |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 228 | gfn += pse36_gfn_delta(pte); |
| 229 | |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 230 | ac = write_fault | fetch_fault | user_fault; |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 231 | |
| 232 | real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(gfn), |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 233 | ac); |
Joerg Roedel | 2329d46 | 2010-09-10 17:30:52 +0200 | [diff] [blame] | 234 | if (real_gpa == UNMAPPED_GVA) |
| 235 | return 0; |
| 236 | |
| 237 | walker->gfn = real_gpa >> PAGE_SHIFT; |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 238 | |
Avi Kivity | 815af8d | 2007-01-05 16:36:44 -0800 | [diff] [blame] | 239 | break; |
| 240 | } |
| 241 | |
Avi Kivity | fe135d2 | 2007-12-09 16:15:46 +0200 | [diff] [blame] | 242 | pt_access = pte_access; |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 243 | --walker->level; |
| 244 | } |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 245 | |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 246 | if (!present || eperm || rsvd_fault) |
| 247 | goto error; |
| 248 | |
Avi Kivity | 43a3795 | 2009-06-10 14:12:05 +0300 | [diff] [blame] | 249 | if (write_fault && !is_dirty_gpte(pte)) { |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 250 | bool ret; |
| 251 | |
Avi Kivity | 0742017 | 2009-07-06 12:21:32 +0300 | [diff] [blame] | 252 | trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte)); |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 253 | ret = FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte, |
| 254 | pte|PT_DIRTY_MASK); |
| 255 | if (ret) |
| 256 | goto walk; |
Gui Jianfeng | f3b8c96 | 2010-05-05 09:09:21 +0800 | [diff] [blame] | 257 | mark_page_dirty(vcpu->kvm, table_gfn); |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 258 | pte |= PT_DIRTY_MASK; |
Marcelo Tosatti | 7819026 | 2007-12-11 19:12:27 -0500 | [diff] [blame] | 259 | walker->ptes[walker->level - 1] = pte; |
Avi Kivity | 42bf3f0 | 2007-10-17 12:18:47 +0200 | [diff] [blame] | 260 | } |
| 261 | |
Avi Kivity | fe135d2 | 2007-12-09 16:15:46 +0200 | [diff] [blame] | 262 | walker->pt_access = pt_access; |
| 263 | walker->pte_access = pte_access; |
| 264 | pgprintk("%s: pte %llx pte_access %x pt_access %x\n", |
Gui Jianfeng | 518c5a0 | 2010-05-05 09:58:33 +0800 | [diff] [blame] | 265 | __func__, (u64)pte, pte_access, pt_access); |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 266 | return 1; |
| 267 | |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 268 | error: |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 269 | walker->fault.vector = PF_VECTOR; |
| 270 | walker->fault.error_code_valid = true; |
| 271 | walker->fault.error_code = 0; |
Avi Kivity | f59c1d2 | 2010-07-06 16:20:43 +0300 | [diff] [blame] | 272 | if (present) |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 273 | walker->fault.error_code |= PFERR_PRESENT_MASK; |
Xiao Guangrong | 20bd40d | 2010-09-27 18:03:27 +0800 | [diff] [blame] | 274 | |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 275 | walker->fault.error_code |= write_fault | user_fault; |
Xiao Guangrong | 20bd40d | 2010-09-27 18:03:27 +0800 | [diff] [blame] | 276 | |
Joerg Roedel | 2d48a98 | 2010-09-10 17:31:01 +0200 | [diff] [blame] | 277 | if (fetch_fault && mmu->nx) |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 278 | walker->fault.error_code |= PFERR_FETCH_MASK; |
Dong, Eddie | 82725b2 | 2009-03-30 16:21:08 +0800 | [diff] [blame] | 279 | if (rsvd_fault) |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 280 | walker->fault.error_code |= PFERR_RSVD_MASK; |
Joerg Roedel | 8df25a3 | 2010-09-10 17:30:46 +0200 | [diff] [blame] | 281 | |
| 282 | vcpu->arch.fault.address = addr; |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 283 | vcpu->arch.fault.error_code = walker->fault.error_code; |
Joerg Roedel | 8df25a3 | 2010-09-10 17:30:46 +0200 | [diff] [blame] | 284 | |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 285 | trace_kvm_mmu_walker_error(walker->fault.error_code); |
Shaohua Li | fe55188 | 2007-07-23 14:51:39 +0800 | [diff] [blame] | 286 | return 0; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 287 | } |
| 288 | |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 289 | static int FNAME(walk_addr)(struct guest_walker *walker, |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 290 | struct kvm_vcpu *vcpu, gva_t addr, u32 access) |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 291 | { |
| 292 | return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.mmu, addr, |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 293 | access); |
Joerg Roedel | 1e301fe | 2010-09-10 17:30:47 +0200 | [diff] [blame] | 294 | } |
| 295 | |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 296 | static int FNAME(walk_addr_nested)(struct guest_walker *walker, |
| 297 | struct kvm_vcpu *vcpu, gva_t addr, |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 298 | u32 access) |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 299 | { |
| 300 | return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.nested_mmu, |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 301 | addr, access); |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 302 | } |
| 303 | |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 304 | static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu, |
| 305 | struct kvm_mmu_page *sp, u64 *spte, |
| 306 | pt_element_t gpte) |
| 307 | { |
| 308 | u64 nonpresent = shadow_trap_nonpresent_pte; |
| 309 | |
| 310 | if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL)) |
| 311 | goto no_present; |
| 312 | |
| 313 | if (!is_present_gpte(gpte)) { |
| 314 | if (!sp->unsync) |
| 315 | nonpresent = shadow_notrap_nonpresent_pte; |
| 316 | goto no_present; |
| 317 | } |
| 318 | |
| 319 | if (!(gpte & PT_ACCESSED_MASK)) |
| 320 | goto no_present; |
| 321 | |
| 322 | return false; |
| 323 | |
| 324 | no_present: |
| 325 | drop_spte(vcpu->kvm, spte, nonpresent); |
| 326 | return true; |
| 327 | } |
| 328 | |
Xiao Guangrong | ac3cd03 | 2010-06-11 21:28:14 +0800 | [diff] [blame] | 329 | static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, |
Dong, Eddie | 489f1d6 | 2008-01-07 11:14:20 +0200 | [diff] [blame] | 330 | u64 *spte, const void *pte) |
Avi Kivity | 0028425 | 2007-05-01 16:53:31 +0300 | [diff] [blame] | 331 | { |
| 332 | pt_element_t gpte; |
Avi Kivity | 41074d0 | 2007-12-09 17:00:02 +0200 | [diff] [blame] | 333 | unsigned pte_access; |
Anthony Liguori | 35149e2 | 2008-04-02 14:46:56 -0500 | [diff] [blame] | 334 | pfn_t pfn; |
Avi Kivity | 0028425 | 2007-05-01 16:53:31 +0300 | [diff] [blame] | 335 | |
Avi Kivity | 0028425 | 2007-05-01 16:53:31 +0300 | [diff] [blame] | 336 | gpte = *(const pt_element_t *)pte; |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 337 | if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte)) |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 338 | return; |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 339 | |
Harvey Harrison | b8688d5 | 2008-03-03 12:59:56 -0800 | [diff] [blame] | 340 | pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte); |
Xiao Guangrong | ac3cd03 | 2010-06-11 21:28:14 +0800 | [diff] [blame] | 341 | pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte); |
Avi Kivity | d7824ff | 2007-12-30 12:29:05 +0200 | [diff] [blame] | 342 | if (gpte_to_gfn(gpte) != vcpu->arch.update_pte.gfn) |
| 343 | return; |
Anthony Liguori | 35149e2 | 2008-04-02 14:46:56 -0500 | [diff] [blame] | 344 | pfn = vcpu->arch.update_pte.pfn; |
| 345 | if (is_error_pfn(pfn)) |
Avi Kivity | d7824ff | 2007-12-30 12:29:05 +0200 | [diff] [blame] | 346 | return; |
Andrea Arcangeli | e930bff | 2008-07-25 16:24:52 +0200 | [diff] [blame] | 347 | if (mmu_notifier_retry(vcpu, vcpu->arch.update_pte.mmu_seq)) |
| 348 | return; |
Anthony Liguori | 35149e2 | 2008-04-02 14:46:56 -0500 | [diff] [blame] | 349 | kvm_get_pfn(pfn); |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 350 | /* |
Lai Jiangshan | 9bdbba1 | 2010-11-19 17:03:22 +0800 | [diff] [blame] | 351 | * we call mmu_set_spte() with host_writable = true beacuse that |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 352 | * vcpu->arch.update_pte.pfn was fetched from get_user_pages(write = 1). |
| 353 | */ |
Xiao Guangrong | ac3cd03 | 2010-06-11 21:28:14 +0800 | [diff] [blame] | 354 | mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0, |
Xiao Guangrong | cb83cad | 2010-06-11 21:29:42 +0800 | [diff] [blame] | 355 | is_dirty_gpte(gpte), NULL, PT_PAGE_TABLE_LEVEL, |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 356 | gpte_to_gfn(gpte), pfn, true, true); |
Avi Kivity | 0028425 | 2007-05-01 16:53:31 +0300 | [diff] [blame] | 357 | } |
| 358 | |
Avi Kivity | 39c8c67 | 2010-07-13 14:27:08 +0300 | [diff] [blame] | 359 | static bool FNAME(gpte_changed)(struct kvm_vcpu *vcpu, |
| 360 | struct guest_walker *gw, int level) |
| 361 | { |
Avi Kivity | 39c8c67 | 2010-07-13 14:27:08 +0300 | [diff] [blame] | 362 | pt_element_t curr_pte; |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 363 | gpa_t base_gpa, pte_gpa = gw->pte_gpa[level - 1]; |
| 364 | u64 mask; |
| 365 | int r, index; |
Avi Kivity | 39c8c67 | 2010-07-13 14:27:08 +0300 | [diff] [blame] | 366 | |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 367 | if (level == PT_PAGE_TABLE_LEVEL) { |
| 368 | mask = PTE_PREFETCH_NUM * sizeof(pt_element_t) - 1; |
| 369 | base_gpa = pte_gpa & ~mask; |
| 370 | index = (pte_gpa - base_gpa) / sizeof(pt_element_t); |
| 371 | |
| 372 | r = kvm_read_guest_atomic(vcpu->kvm, base_gpa, |
| 373 | gw->prefetch_ptes, sizeof(gw->prefetch_ptes)); |
| 374 | curr_pte = gw->prefetch_ptes[index]; |
| 375 | } else |
| 376 | r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, |
Avi Kivity | 39c8c67 | 2010-07-13 14:27:08 +0300 | [diff] [blame] | 377 | &curr_pte, sizeof(curr_pte)); |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 378 | |
Avi Kivity | 39c8c67 | 2010-07-13 14:27:08 +0300 | [diff] [blame] | 379 | return r || curr_pte != gw->ptes[level - 1]; |
| 380 | } |
| 381 | |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 382 | static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, |
| 383 | u64 *sptep) |
Xiao Guangrong | 957ed9e | 2010-08-22 19:12:48 +0800 | [diff] [blame] | 384 | { |
| 385 | struct kvm_mmu_page *sp; |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 386 | pt_element_t *gptep = gw->prefetch_ptes; |
Xiao Guangrong | 957ed9e | 2010-08-22 19:12:48 +0800 | [diff] [blame] | 387 | u64 *spte; |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 388 | int i; |
Xiao Guangrong | 957ed9e | 2010-08-22 19:12:48 +0800 | [diff] [blame] | 389 | |
| 390 | sp = page_header(__pa(sptep)); |
| 391 | |
| 392 | if (sp->role.level > PT_PAGE_TABLE_LEVEL) |
| 393 | return; |
| 394 | |
| 395 | if (sp->role.direct) |
| 396 | return __direct_pte_prefetch(vcpu, sp, sptep); |
| 397 | |
| 398 | i = (sptep - sp->spt) & ~(PTE_PREFETCH_NUM - 1); |
Xiao Guangrong | 957ed9e | 2010-08-22 19:12:48 +0800 | [diff] [blame] | 399 | spte = sp->spt + i; |
| 400 | |
| 401 | for (i = 0; i < PTE_PREFETCH_NUM; i++, spte++) { |
| 402 | pt_element_t gpte; |
| 403 | unsigned pte_access; |
| 404 | gfn_t gfn; |
| 405 | pfn_t pfn; |
| 406 | bool dirty; |
| 407 | |
| 408 | if (spte == sptep) |
| 409 | continue; |
| 410 | |
| 411 | if (*spte != shadow_trap_nonpresent_pte) |
| 412 | continue; |
| 413 | |
| 414 | gpte = gptep[i]; |
| 415 | |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 416 | if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte)) |
Xiao Guangrong | 957ed9e | 2010-08-22 19:12:48 +0800 | [diff] [blame] | 417 | continue; |
| 418 | |
| 419 | pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte); |
| 420 | gfn = gpte_to_gfn(gpte); |
| 421 | dirty = is_dirty_gpte(gpte); |
| 422 | pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn, |
| 423 | (pte_access & ACC_WRITE_MASK) && dirty); |
| 424 | if (is_error_pfn(pfn)) { |
| 425 | kvm_release_pfn_clean(pfn); |
| 426 | break; |
| 427 | } |
| 428 | |
| 429 | mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0, |
| 430 | dirty, NULL, PT_PAGE_TABLE_LEVEL, gfn, |
| 431 | pfn, true, true); |
| 432 | } |
| 433 | } |
| 434 | |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 435 | /* |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 436 | * Fetch a shadow pte for a specific level in the paging hierarchy. |
| 437 | */ |
| 438 | static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, |
Avi Kivity | e7a04c9 | 2008-12-25 15:10:50 +0200 | [diff] [blame] | 439 | struct guest_walker *gw, |
Joerg Roedel | 7e4e405 | 2009-07-27 16:30:46 +0200 | [diff] [blame] | 440 | int user_fault, int write_fault, int hlevel, |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 441 | int *ptwrite, pfn_t pfn, bool map_writable) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 442 | { |
Avi Kivity | e7a04c9 | 2008-12-25 15:10:50 +0200 | [diff] [blame] | 443 | unsigned access = gw->pt_access; |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 444 | struct kvm_mmu_page *sp = NULL; |
Xiao Guangrong | 84754cd | 2010-06-30 16:05:00 +0800 | [diff] [blame] | 445 | bool dirty = is_dirty_gpte(gw->ptes[gw->level - 1]); |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 446 | int top_level; |
Xiao Guangrong | 84754cd | 2010-06-30 16:05:00 +0800 | [diff] [blame] | 447 | unsigned direct_access; |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 448 | struct kvm_shadow_walk_iterator it; |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 449 | |
Avi Kivity | 43a3795 | 2009-06-10 14:12:05 +0300 | [diff] [blame] | 450 | if (!is_present_gpte(gw->ptes[gw->level - 1])) |
Avi Kivity | ac79c97 | 2007-01-05 16:36:40 -0800 | [diff] [blame] | 451 | return NULL; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 452 | |
Xiao Guangrong | 84754cd | 2010-06-30 16:05:00 +0800 | [diff] [blame] | 453 | direct_access = gw->pt_access & gw->pte_access; |
| 454 | if (!dirty) |
| 455 | direct_access &= ~ACC_WRITE_MASK; |
| 456 | |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 457 | top_level = vcpu->arch.mmu.root_level; |
| 458 | if (top_level == PT32E_ROOT_LEVEL) |
| 459 | top_level = PT32_ROOT_LEVEL; |
| 460 | /* |
| 461 | * Verify that the top-level gpte is still there. Since the page |
| 462 | * is a root page, it is either write protected (and cannot be |
| 463 | * changed from now on) or it is invalid (in which case, we don't |
| 464 | * really care if it changes underneath us after this point). |
| 465 | */ |
| 466 | if (FNAME(gpte_changed)(vcpu, gw, top_level)) |
| 467 | goto out_gpte_changed; |
| 468 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 469 | for (shadow_walk_init(&it, vcpu, addr); |
| 470 | shadow_walk_okay(&it) && it.level > gw->level; |
| 471 | shadow_walk_next(&it)) { |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 472 | gfn_t table_gfn; |
| 473 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 474 | drop_large_spte(vcpu, it.sptep); |
Avi Kivity | e7a04c9 | 2008-12-25 15:10:50 +0200 | [diff] [blame] | 475 | |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 476 | sp = NULL; |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 477 | if (!is_shadow_present_pte(*it.sptep)) { |
| 478 | table_gfn = gw->table_gfn[it.level - 2]; |
| 479 | sp = kvm_mmu_get_page(vcpu, table_gfn, addr, it.level-1, |
| 480 | false, access, it.sptep); |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 481 | } |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 482 | |
| 483 | /* |
| 484 | * Verify that the gpte in the page we've just write |
| 485 | * protected is still there. |
| 486 | */ |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 487 | if (FNAME(gpte_changed)(vcpu, gw, it.level - 1)) |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 488 | goto out_gpte_changed; |
Avi Kivity | e7a04c9 | 2008-12-25 15:10:50 +0200 | [diff] [blame] | 489 | |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 490 | if (sp) |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 491 | link_shadow_page(it.sptep, sp); |
Avi Kivity | e7a04c9 | 2008-12-25 15:10:50 +0200 | [diff] [blame] | 492 | } |
| 493 | |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 494 | for (; |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 495 | shadow_walk_okay(&it) && it.level > hlevel; |
| 496 | shadow_walk_next(&it)) { |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 497 | gfn_t direct_gfn; |
| 498 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 499 | validate_direct_spte(vcpu, it.sptep, direct_access); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 500 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 501 | drop_large_spte(vcpu, it.sptep); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 502 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 503 | if (is_shadow_present_pte(*it.sptep)) |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 504 | continue; |
| 505 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 506 | direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 507 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 508 | sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1, |
| 509 | true, direct_access, it.sptep); |
| 510 | link_shadow_page(it.sptep, sp); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 511 | } |
| 512 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 513 | mmu_set_spte(vcpu, it.sptep, access, gw->pte_access & access, |
| 514 | user_fault, write_fault, dirty, ptwrite, it.level, |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 515 | gw->gfn, pfn, false, map_writable); |
Xiao Guangrong | 189be38 | 2010-08-22 19:13:33 +0800 | [diff] [blame] | 516 | FNAME(pte_prefetch)(vcpu, gw, it.sptep); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 517 | |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 518 | return it.sptep; |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 519 | |
| 520 | out_gpte_changed: |
Avi Kivity | 5991b33 | 2010-07-13 14:27:10 +0300 | [diff] [blame] | 521 | if (sp) |
Avi Kivity | 24157aa | 2010-07-13 14:27:11 +0300 | [diff] [blame] | 522 | kvm_mmu_put_page(sp, it.sptep); |
Avi Kivity | 0b3c933 | 2010-07-13 14:27:09 +0300 | [diff] [blame] | 523 | kvm_release_pfn_clean(pfn); |
| 524 | return NULL; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 525 | } |
| 526 | |
| 527 | /* |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 528 | * Page fault handler. There are several causes for a page fault: |
| 529 | * - there is no shadow pte for the guest pte |
| 530 | * - write access through a shadow pte marked read only so that we can set |
| 531 | * the dirty bit |
| 532 | * - write access to a shadow pte marked read only so we can update the page |
| 533 | * dirty bitmap, when userspace requests it |
| 534 | * - mmio access; in this case we will never install a present shadow pte |
| 535 | * - normal guest page fault due to the guest pte marked not present, not |
| 536 | * writable, or not executable |
| 537 | * |
Avi Kivity | e2dec93 | 2007-01-05 16:36:54 -0800 | [diff] [blame] | 538 | * Returns: 1 if we need to emulate the instruction, 0 otherwise, or |
| 539 | * a negative value on error. |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 540 | */ |
Gleb Natapov | 56028d0 | 2010-10-17 18:13:42 +0200 | [diff] [blame] | 541 | static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, |
| 542 | bool no_apf) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 543 | { |
| 544 | int write_fault = error_code & PFERR_WRITE_MASK; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 545 | int user_fault = error_code & PFERR_USER_MASK; |
| 546 | struct guest_walker walker; |
Avi Kivity | d555c33 | 2009-06-10 14:24:23 +0300 | [diff] [blame] | 547 | u64 *sptep; |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 548 | int write_pt = 0; |
Avi Kivity | e2dec93 | 2007-01-05 16:36:54 -0800 | [diff] [blame] | 549 | int r; |
Anthony Liguori | 35149e2 | 2008-04-02 14:46:56 -0500 | [diff] [blame] | 550 | pfn_t pfn; |
Joerg Roedel | 7e4e405 | 2009-07-27 16:30:46 +0200 | [diff] [blame] | 551 | int level = PT_PAGE_TABLE_LEVEL; |
Andrea Arcangeli | e930bff | 2008-07-25 16:24:52 +0200 | [diff] [blame] | 552 | unsigned long mmu_seq; |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 553 | bool map_writable; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 554 | |
Harvey Harrison | b8688d5 | 2008-03-03 12:59:56 -0800 | [diff] [blame] | 555 | pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code); |
Avi Kivity | 714b93d | 2007-01-05 16:36:53 -0800 | [diff] [blame] | 556 | |
Avi Kivity | e2dec93 | 2007-01-05 16:36:54 -0800 | [diff] [blame] | 557 | r = mmu_topup_memory_caches(vcpu); |
| 558 | if (r) |
| 559 | return r; |
Avi Kivity | 714b93d | 2007-01-05 16:36:53 -0800 | [diff] [blame] | 560 | |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 561 | /* |
Eddie Dong | a8b876b | 2009-03-26 15:28:40 +0800 | [diff] [blame] | 562 | * Look up the guest pte for the faulting address. |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 563 | */ |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 564 | r = FNAME(walk_addr)(&walker, vcpu, addr, error_code); |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 565 | |
| 566 | /* |
| 567 | * The page is not mapped by the guest. Let the guest handle it. |
| 568 | */ |
Avi Kivity | 7993ba4 | 2007-01-26 00:56:41 -0800 | [diff] [blame] | 569 | if (!r) { |
Harvey Harrison | b8688d5 | 2008-03-03 12:59:56 -0800 | [diff] [blame] | 570 | pgprintk("%s: guest page fault\n", __func__); |
Joerg Roedel | 8df25a3 | 2010-09-10 17:30:46 +0200 | [diff] [blame] | 571 | inject_page_fault(vcpu); |
Zhang Xiantao | ad312c7 | 2007-12-13 23:50:52 +0800 | [diff] [blame] | 572 | vcpu->arch.last_pt_write_count = 0; /* reset fork detector */ |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 573 | return 0; |
| 574 | } |
| 575 | |
Joerg Roedel | 7e4e405 | 2009-07-27 16:30:46 +0200 | [diff] [blame] | 576 | if (walker.level >= PT_DIRECTORY_LEVEL) { |
| 577 | level = min(walker.level, mapping_level(vcpu, walker.gfn)); |
| 578 | walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1); |
Marcelo Tosatti | 05da455 | 2008-02-23 11:44:30 -0300 | [diff] [blame] | 579 | } |
Joerg Roedel | 7e4e405 | 2009-07-27 16:30:46 +0200 | [diff] [blame] | 580 | |
Andrea Arcangeli | e930bff | 2008-07-25 16:24:52 +0200 | [diff] [blame] | 581 | mmu_seq = vcpu->kvm->mmu_notifier_seq; |
Marcelo Tosatti | 4c2155c | 2008-09-16 20:54:47 -0300 | [diff] [blame] | 582 | smp_rmb(); |
Gleb Natapov | af585b9 | 2010-10-14 11:22:46 +0200 | [diff] [blame] | 583 | |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 584 | if (try_async_pf(vcpu, no_apf, walker.gfn, addr, &pfn, write_fault, |
| 585 | &map_writable)) |
Gleb Natapov | af585b9 | 2010-10-14 11:22:46 +0200 | [diff] [blame] | 586 | return 0; |
Avi Kivity | d7824ff | 2007-12-30 12:29:05 +0200 | [diff] [blame] | 587 | |
Avi Kivity | d196e34 | 2008-01-24 11:44:11 +0200 | [diff] [blame] | 588 | /* mmio */ |
Huang Ying | bf99815 | 2010-05-31 14:28:19 +0800 | [diff] [blame] | 589 | if (is_error_pfn(pfn)) |
| 590 | return kvm_handle_bad_page(vcpu->kvm, walker.gfn, pfn); |
Avi Kivity | d196e34 | 2008-01-24 11:44:11 +0200 | [diff] [blame] | 591 | |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 592 | if (!map_writable) |
| 593 | walker.pte_access &= ~ACC_WRITE_MASK; |
| 594 | |
Marcelo Tosatti | aaee2c9 | 2007-12-20 19:18:26 -0500 | [diff] [blame] | 595 | spin_lock(&vcpu->kvm->mmu_lock); |
Andrea Arcangeli | e930bff | 2008-07-25 16:24:52 +0200 | [diff] [blame] | 596 | if (mmu_notifier_retry(vcpu, mmu_seq)) |
| 597 | goto out_unlock; |
Xiao Guangrong | bc32ce2 | 2010-08-28 19:22:46 +0800 | [diff] [blame] | 598 | |
Xiao Guangrong | 8b1fe17 | 2010-08-30 18:22:53 +0800 | [diff] [blame] | 599 | trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); |
Avi Kivity | eb787d1 | 2007-12-31 15:27:49 +0200 | [diff] [blame] | 600 | kvm_mmu_free_some_pages(vcpu); |
Avi Kivity | d555c33 | 2009-06-10 14:24:23 +0300 | [diff] [blame] | 601 | sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, |
Marcelo Tosatti | 612819c | 2010-10-22 14:18:18 -0200 | [diff] [blame] | 602 | level, &write_pt, pfn, map_writable); |
Andi Kleen | a24e809 | 2010-06-10 13:10:55 +0200 | [diff] [blame] | 603 | (void)sptep; |
Harvey Harrison | b8688d5 | 2008-03-03 12:59:56 -0800 | [diff] [blame] | 604 | pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__, |
Avi Kivity | d555c33 | 2009-06-10 14:24:23 +0300 | [diff] [blame] | 605 | sptep, *sptep, write_pt); |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 606 | |
Avi Kivity | a25f7e1 | 2007-04-30 17:05:38 +0300 | [diff] [blame] | 607 | if (!write_pt) |
Zhang Xiantao | ad312c7 | 2007-12-13 23:50:52 +0800 | [diff] [blame] | 608 | vcpu->arch.last_pt_write_count = 0; /* reset fork detector */ |
Avi Kivity | a25f7e1 | 2007-04-30 17:05:38 +0300 | [diff] [blame] | 609 | |
Avi Kivity | 1165f5f | 2007-04-19 17:27:43 +0300 | [diff] [blame] | 610 | ++vcpu->stat.pf_fixed; |
Xiao Guangrong | 8b1fe17 | 2010-08-30 18:22:53 +0800 | [diff] [blame] | 611 | trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT); |
Marcelo Tosatti | aaee2c9 | 2007-12-20 19:18:26 -0500 | [diff] [blame] | 612 | spin_unlock(&vcpu->kvm->mmu_lock); |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 613 | |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 614 | return write_pt; |
Andrea Arcangeli | e930bff | 2008-07-25 16:24:52 +0200 | [diff] [blame] | 615 | |
| 616 | out_unlock: |
| 617 | spin_unlock(&vcpu->kvm->mmu_lock); |
| 618 | kvm_release_pfn_clean(pfn); |
| 619 | return 0; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 620 | } |
| 621 | |
Marcelo Tosatti | a705289 | 2008-09-23 13:18:35 -0300 | [diff] [blame] | 622 | static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva) |
| 623 | { |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 624 | struct kvm_shadow_walk_iterator iterator; |
Xiao Guangrong | f78978a | 2010-05-15 18:53:35 +0800 | [diff] [blame] | 625 | struct kvm_mmu_page *sp; |
Avi Kivity | 08e850c | 2010-03-15 13:59:57 +0200 | [diff] [blame] | 626 | gpa_t pte_gpa = -1; |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 627 | int level; |
| 628 | u64 *sptep; |
Andrea Arcangeli | 4539b35 | 2009-03-12 18:18:43 +0100 | [diff] [blame] | 629 | int need_flush = 0; |
Marcelo Tosatti | a705289 | 2008-09-23 13:18:35 -0300 | [diff] [blame] | 630 | |
Marcelo Tosatti | ad218f8 | 2008-12-01 22:32:05 -0200 | [diff] [blame] | 631 | spin_lock(&vcpu->kvm->mmu_lock); |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 632 | |
| 633 | for_each_shadow_entry(vcpu, gva, iterator) { |
| 634 | level = iterator.level; |
| 635 | sptep = iterator.sptep; |
| 636 | |
Xiao Guangrong | f78978a | 2010-05-15 18:53:35 +0800 | [diff] [blame] | 637 | sp = page_header(__pa(sptep)); |
Xiao Guangrong | 884a0ff | 2010-04-28 11:55:15 +0800 | [diff] [blame] | 638 | if (is_last_spte(*sptep, level)) { |
Xiao Guangrong | 22c9b2d | 2010-04-28 11:54:44 +0800 | [diff] [blame] | 639 | int offset, shift; |
Avi Kivity | 08e850c | 2010-03-15 13:59:57 +0200 | [diff] [blame] | 640 | |
Xiao Guangrong | f78978a | 2010-05-15 18:53:35 +0800 | [diff] [blame] | 641 | if (!sp->unsync) |
| 642 | break; |
| 643 | |
Xiao Guangrong | 22c9b2d | 2010-04-28 11:54:44 +0800 | [diff] [blame] | 644 | shift = PAGE_SHIFT - |
| 645 | (PT_LEVEL_BITS - PT64_LEVEL_BITS) * level; |
| 646 | offset = sp->role.quadrant << shift; |
| 647 | |
| 648 | pte_gpa = (sp->gfn << PAGE_SHIFT) + offset; |
Avi Kivity | 08e850c | 2010-03-15 13:59:57 +0200 | [diff] [blame] | 649 | pte_gpa += (sptep - sp->spt) * sizeof(pt_element_t); |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 650 | |
| 651 | if (is_shadow_present_pte(*sptep)) { |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 652 | if (is_large_pte(*sptep)) |
| 653 | --vcpu->kvm->stat.lpages; |
Avi Kivity | be38d27 | 2010-06-06 14:31:27 +0300 | [diff] [blame] | 654 | drop_spte(vcpu->kvm, sptep, |
| 655 | shadow_trap_nonpresent_pte); |
Andrea Arcangeli | 4539b35 | 2009-03-12 18:18:43 +0100 | [diff] [blame] | 656 | need_flush = 1; |
Avi Kivity | be38d27 | 2010-06-06 14:31:27 +0300 | [diff] [blame] | 657 | } else |
| 658 | __set_spte(sptep, shadow_trap_nonpresent_pte); |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 659 | break; |
| 660 | } |
| 661 | |
Xiao Guangrong | f78978a | 2010-05-15 18:53:35 +0800 | [diff] [blame] | 662 | if (!is_shadow_present_pte(*sptep) || !sp->unsync_children) |
Avi Kivity | a461930 | 2008-12-25 15:19:00 +0200 | [diff] [blame] | 663 | break; |
| 664 | } |
| 665 | |
Andrea Arcangeli | 4539b35 | 2009-03-12 18:18:43 +0100 | [diff] [blame] | 666 | if (need_flush) |
| 667 | kvm_flush_remote_tlbs(vcpu->kvm); |
Avi Kivity | 08e850c | 2010-03-15 13:59:57 +0200 | [diff] [blame] | 668 | |
| 669 | atomic_inc(&vcpu->kvm->arch.invlpg_counter); |
| 670 | |
Marcelo Tosatti | ad218f8 | 2008-12-01 22:32:05 -0200 | [diff] [blame] | 671 | spin_unlock(&vcpu->kvm->mmu_lock); |
Avi Kivity | 08e850c | 2010-03-15 13:59:57 +0200 | [diff] [blame] | 672 | |
| 673 | if (pte_gpa == -1) |
| 674 | return; |
| 675 | |
| 676 | if (mmu_topup_memory_caches(vcpu)) |
| 677 | return; |
| 678 | kvm_mmu_pte_write(vcpu, pte_gpa, NULL, sizeof(pt_element_t), 0); |
Marcelo Tosatti | a705289 | 2008-09-23 13:18:35 -0300 | [diff] [blame] | 679 | } |
| 680 | |
Gleb Natapov | 1871c60 | 2010-02-10 14:21:32 +0200 | [diff] [blame] | 681 | static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access, |
Avi Kivity | ab9ae31 | 2010-11-22 17:53:26 +0200 | [diff] [blame] | 682 | struct x86_exception *exception) |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 683 | { |
| 684 | struct guest_walker walker; |
Avi Kivity | e119d11 | 2007-02-12 00:54:36 -0800 | [diff] [blame] | 685 | gpa_t gpa = UNMAPPED_GVA; |
| 686 | int r; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 687 | |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 688 | r = FNAME(walk_addr)(&walker, vcpu, vaddr, access); |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 689 | |
Avi Kivity | e119d11 | 2007-02-12 00:54:36 -0800 | [diff] [blame] | 690 | if (r) { |
Avi Kivity | 1755fbc | 2007-11-21 14:44:45 +0200 | [diff] [blame] | 691 | gpa = gfn_to_gpa(walker.gfn); |
Avi Kivity | e119d11 | 2007-02-12 00:54:36 -0800 | [diff] [blame] | 692 | gpa |= vaddr & ~PAGE_MASK; |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 693 | } else if (exception) |
| 694 | *exception = walker.fault; |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 695 | |
| 696 | return gpa; |
| 697 | } |
| 698 | |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 699 | static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gva_t vaddr, |
Avi Kivity | ab9ae31 | 2010-11-22 17:53:26 +0200 | [diff] [blame] | 700 | u32 access, |
| 701 | struct x86_exception *exception) |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 702 | { |
| 703 | struct guest_walker walker; |
| 704 | gpa_t gpa = UNMAPPED_GVA; |
| 705 | int r; |
| 706 | |
Xiao Guangrong | 3377078 | 2010-09-28 17:03:14 +0800 | [diff] [blame] | 707 | r = FNAME(walk_addr_nested)(&walker, vcpu, vaddr, access); |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 708 | |
| 709 | if (r) { |
| 710 | gpa = gfn_to_gpa(walker.gfn); |
| 711 | gpa |= vaddr & ~PAGE_MASK; |
Avi Kivity | 8c28d03 | 2010-11-22 17:53:27 +0200 | [diff] [blame^] | 712 | } else if (exception) |
| 713 | *exception = walker.fault; |
Joerg Roedel | 6539e73 | 2010-09-10 17:30:50 +0200 | [diff] [blame] | 714 | |
| 715 | return gpa; |
| 716 | } |
| 717 | |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 718 | static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu, |
| 719 | struct kvm_mmu_page *sp) |
| 720 | { |
Avi Kivity | eab9f71 | 2008-05-29 14:20:16 +0300 | [diff] [blame] | 721 | int i, j, offset, r; |
| 722 | pt_element_t pt[256 / sizeof(pt_element_t)]; |
| 723 | gpa_t pte_gpa; |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 724 | |
Avi Kivity | f6e2c02 | 2009-01-11 13:02:10 +0200 | [diff] [blame] | 725 | if (sp->role.direct |
Avi Kivity | e5a4c8c | 2007-11-20 21:39:54 +0200 | [diff] [blame] | 726 | || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) { |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 727 | nonpaging_prefetch_page(vcpu, sp); |
| 728 | return; |
| 729 | } |
| 730 | |
Avi Kivity | eab9f71 | 2008-05-29 14:20:16 +0300 | [diff] [blame] | 731 | pte_gpa = gfn_to_gpa(sp->gfn); |
| 732 | if (PTTYPE == 32) { |
Avi Kivity | e5a4c8c | 2007-11-20 21:39:54 +0200 | [diff] [blame] | 733 | offset = sp->role.quadrant << PT64_LEVEL_BITS; |
Avi Kivity | eab9f71 | 2008-05-29 14:20:16 +0300 | [diff] [blame] | 734 | pte_gpa += offset * sizeof(pt_element_t); |
| 735 | } |
Marcelo Tosatti | 7ec5458 | 2007-12-20 19:18:23 -0500 | [diff] [blame] | 736 | |
Avi Kivity | eab9f71 | 2008-05-29 14:20:16 +0300 | [diff] [blame] | 737 | for (i = 0; i < PT64_ENT_PER_PAGE; i += ARRAY_SIZE(pt)) { |
| 738 | r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa, pt, sizeof pt); |
| 739 | pte_gpa += ARRAY_SIZE(pt) * sizeof(pt_element_t); |
| 740 | for (j = 0; j < ARRAY_SIZE(pt); ++j) |
Avi Kivity | 43a3795 | 2009-06-10 14:12:05 +0300 | [diff] [blame] | 741 | if (r || is_present_gpte(pt[j])) |
Avi Kivity | eab9f71 | 2008-05-29 14:20:16 +0300 | [diff] [blame] | 742 | sp->spt[i+j] = shadow_trap_nonpresent_pte; |
| 743 | else |
| 744 | sp->spt[i+j] = shadow_notrap_nonpresent_pte; |
Marcelo Tosatti | 7ec5458 | 2007-12-20 19:18:23 -0500 | [diff] [blame] | 745 | } |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 746 | } |
| 747 | |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 748 | /* |
| 749 | * Using the cached information from sp->gfns is safe because: |
| 750 | * - The spte has a reference to the struct page, so the pfn for a given gfn |
| 751 | * can't change unless all sptes pointing to it are nuked first. |
Xiao Guangrong | a4ee1ca | 2010-11-23 11:13:00 +0800 | [diff] [blame] | 752 | * |
| 753 | * Note: |
| 754 | * We should flush all tlbs if spte is dropped even though guest is |
| 755 | * responsible for it. Since if we don't, kvm_mmu_notifier_invalidate_page |
| 756 | * and kvm_mmu_notifier_invalidate_range_start detect the mapping page isn't |
| 757 | * used by guest then tlbs are not flushed, so guest is allowed to access the |
| 758 | * freed pages. |
| 759 | * And we increase kvm->tlbs_dirty to delay tlbs flush in this case. |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 760 | */ |
Xiao Guangrong | a4a8e6f | 2010-11-19 17:04:03 +0800 | [diff] [blame] | 761 | static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 762 | { |
| 763 | int i, offset, nr_present; |
Lai Jiangshan | 9bdbba1 | 2010-11-19 17:03:22 +0800 | [diff] [blame] | 764 | bool host_writable; |
Gui Jianfeng | 51fb60d | 2010-04-16 17:16:40 +0800 | [diff] [blame] | 765 | gpa_t first_pte_gpa; |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 766 | |
| 767 | offset = nr_present = 0; |
| 768 | |
Lai Jiangshan | 2032a93 | 2010-05-26 16:49:59 +0800 | [diff] [blame] | 769 | /* direct kvm_mmu_page can not be unsync. */ |
| 770 | BUG_ON(sp->role.direct); |
| 771 | |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 772 | if (PTTYPE == 32) |
| 773 | offset = sp->role.quadrant << PT64_LEVEL_BITS; |
| 774 | |
Gui Jianfeng | 51fb60d | 2010-04-16 17:16:40 +0800 | [diff] [blame] | 775 | first_pte_gpa = gfn_to_gpa(sp->gfn) + offset * sizeof(pt_element_t); |
| 776 | |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 777 | for (i = 0; i < PT64_ENT_PER_PAGE; i++) { |
| 778 | unsigned pte_access; |
| 779 | pt_element_t gpte; |
| 780 | gpa_t pte_gpa; |
Xiao Guangrong | f55c3f4 | 2010-05-13 10:08:08 +0800 | [diff] [blame] | 781 | gfn_t gfn; |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 782 | |
| 783 | if (!is_shadow_present_pte(sp->spt[i])) |
| 784 | continue; |
| 785 | |
Gui Jianfeng | 51fb60d | 2010-04-16 17:16:40 +0800 | [diff] [blame] | 786 | pte_gpa = first_pte_gpa + i * sizeof(pt_element_t); |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 787 | |
| 788 | if (kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &gpte, |
| 789 | sizeof(pt_element_t))) |
| 790 | return -EINVAL; |
| 791 | |
Xiao Guangrong | f55c3f4 | 2010-05-13 10:08:08 +0800 | [diff] [blame] | 792 | gfn = gpte_to_gfn(gpte); |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 793 | |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 794 | if (FNAME(prefetch_invalid_gpte)(vcpu, sp, &sp->spt[i], gpte)) { |
Xiao Guangrong | a4ee1ca | 2010-11-23 11:13:00 +0800 | [diff] [blame] | 795 | vcpu->kvm->tlbs_dirty++; |
Xiao Guangrong | 407c61c | 2010-11-23 11:08:42 +0800 | [diff] [blame] | 796 | continue; |
| 797 | } |
| 798 | |
| 799 | if (gfn != sp->gfns[i]) { |
| 800 | drop_spte(vcpu->kvm, &sp->spt[i], |
| 801 | shadow_trap_nonpresent_pte); |
Xiao Guangrong | a4ee1ca | 2010-11-23 11:13:00 +0800 | [diff] [blame] | 802 | vcpu->kvm->tlbs_dirty++; |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 803 | continue; |
| 804 | } |
| 805 | |
| 806 | nr_present++; |
| 807 | pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte); |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 808 | if (!(sp->spt[i] & SPTE_HOST_WRITEABLE)) { |
| 809 | pte_access &= ~ACC_WRITE_MASK; |
Lai Jiangshan | 9bdbba1 | 2010-11-19 17:03:22 +0800 | [diff] [blame] | 810 | host_writable = 0; |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 811 | } else { |
Lai Jiangshan | 9bdbba1 | 2010-11-19 17:03:22 +0800 | [diff] [blame] | 812 | host_writable = 1; |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 813 | } |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 814 | set_spte(vcpu, &sp->spt[i], pte_access, 0, 0, |
Joerg Roedel | 7e4e405 | 2009-07-27 16:30:46 +0200 | [diff] [blame] | 815 | is_dirty_gpte(gpte), PT_PAGE_TABLE_LEVEL, gfn, |
Izik Eidus | 1403283 | 2009-09-23 21:47:17 +0300 | [diff] [blame] | 816 | spte_to_pfn(sp->spt[i]), true, false, |
Lai Jiangshan | 9bdbba1 | 2010-11-19 17:03:22 +0800 | [diff] [blame] | 817 | host_writable); |
Marcelo Tosatti | e8bc217 | 2008-09-23 13:18:33 -0300 | [diff] [blame] | 818 | } |
| 819 | |
| 820 | return !nr_present; |
| 821 | } |
| 822 | |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 823 | #undef pt_element_t |
| 824 | #undef guest_walker |
| 825 | #undef FNAME |
| 826 | #undef PT_BASE_ADDR_MASK |
| 827 | #undef PT_INDEX |
Avi Kivity | 6aa8b73 | 2006-12-10 02:21:36 -0800 | [diff] [blame] | 828 | #undef PT_LEVEL_MASK |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 829 | #undef PT_LVL_ADDR_MASK |
| 830 | #undef PT_LVL_OFFSET_MASK |
Avi Kivity | c7addb9 | 2007-09-16 18:58:32 +0200 | [diff] [blame] | 831 | #undef PT_LEVEL_BITS |
Avi Kivity | cea0f0e | 2007-01-05 16:36:43 -0800 | [diff] [blame] | 832 | #undef PT_MAX_FULL_LEVELS |
Avi Kivity | 5fb07dd | 2007-11-21 12:35:07 +0200 | [diff] [blame] | 833 | #undef gpte_to_gfn |
Joerg Roedel | e04da98 | 2009-07-27 16:30:45 +0200 | [diff] [blame] | 834 | #undef gpte_to_gfn_lvl |
Marcelo Tosatti | b3e4e63 | 2007-12-07 07:56:58 -0500 | [diff] [blame] | 835 | #undef CMPXCHG |