1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_PGTABLE_64_H
3#define _ASM_X86_PGTABLE_64_H
4
5#include <linux/const.h>
6#include <asm/pgtable_64_types.h>
7
8#ifndef __ASSEMBLY__
9
10/*
11 * This file contains the functions and defines necessary to modify and use
12 * the x86-64 page table tree.
13 */
14#include <asm/processor.h>
15#include <linux/bitops.h>
16#include <linux/threads.h>
17#include <asm/fixmap.h>
18
19extern p4d_t level4_kernel_pgt[512];
20extern p4d_t level4_ident_pgt[512];
21extern pud_t level3_kernel_pgt[512];
22extern pud_t level3_ident_pgt[512];
23extern pmd_t level2_kernel_pgt[512];
24extern pmd_t level2_fixmap_pgt[512];
25extern pmd_t level2_ident_pgt[512];
26extern pte_t level1_fixmap_pgt[512 * FIXMAP_PMD_NUM];
27extern pgd_t init_top_pgt[];
28
29#define swapper_pg_dir init_top_pgt
30
31extern void paging_init(void);
32static inline void sync_initial_page_table(void) { }
33
34#define pte_ERROR(e) \
35 pr_err("%s:%d: bad pte %p(%016lx)\n", \
36 __FILE__, __LINE__, &(e), pte_val(e))
37#define pmd_ERROR(e) \
38 pr_err("%s:%d: bad pmd %p(%016lx)\n", \
39 __FILE__, __LINE__, &(e), pmd_val(e))
40#define pud_ERROR(e) \
41 pr_err("%s:%d: bad pud %p(%016lx)\n", \
42 __FILE__, __LINE__, &(e), pud_val(e))
43
44#if CONFIG_PGTABLE_LEVELS >= 5
45#define p4d_ERROR(e) \
46 pr_err("%s:%d: bad p4d %p(%016lx)\n", \
47 __FILE__, __LINE__, &(e), p4d_val(e))
48#endif
49
50#define pgd_ERROR(e) \
51 pr_err("%s:%d: bad pgd %p(%016lx)\n", \
52 __FILE__, __LINE__, &(e), pgd_val(e))
53
54struct mm_struct;
55
56void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
57void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
58
59static inline void native_set_pte(pte_t *ptep, pte_t pte)
60{
61 WRITE_ONCE(*ptep, pte);
62}
63
64static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
65 pte_t *ptep)
66{
67 native_set_pte(ptep, native_make_pte(0));
68}
69
70static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
71{
72 native_set_pte(ptep, pte);
73}
74
75static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
76{
77 WRITE_ONCE(*pmdp, pmd);
78}
79
80static inline void native_pmd_clear(pmd_t *pmd)
81{
82 native_set_pmd(pmd, native_make_pmd(0));
83}
84
85static inline pte_t native_ptep_get_and_clear(pte_t *xp)
86{
87#ifdef CONFIG_SMP
88 return native_make_pte(xchg(&xp->pte, 0));
89#else
90 /* native_local_ptep_get_and_clear,
91 but duplicated because of cyclic dependency */
92 pte_t ret = *xp;
93 native_pte_clear(NULL, 0, xp);
94 return ret;
95#endif
96}
97
98static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
99{
100#ifdef CONFIG_SMP
101 return native_make_pmd(xchg(&xp->pmd, 0));
102#else
103 /* native_local_pmdp_get_and_clear,
104 but duplicated because of cyclic dependency */
105 pmd_t ret = *xp;
106 native_pmd_clear(xp);
107 return ret;
108#endif
109}
110
111static inline void native_set_pud(pud_t *pudp, pud_t pud)
112{
113 WRITE_ONCE(*pudp, pud);
114}
115
116static inline void native_pud_clear(pud_t *pud)
117{
118 native_set_pud(pud, native_make_pud(0));
119}
120
121static inline pud_t native_pudp_get_and_clear(pud_t *xp)
122{
123#ifdef CONFIG_SMP
124 return native_make_pud(xchg(&xp->pud, 0));
125#else
126 /* native_local_pudp_get_and_clear,
127 * but duplicated because of cyclic dependency
128 */
129 pud_t ret = *xp;
130
131 native_pud_clear(xp);
132 return ret;
133#endif
134}
135
136static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
137{
138 pgd_t pgd;
139
140 if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
141 WRITE_ONCE(*p4dp, p4d);
142 return;
143 }
144
145 pgd = native_make_pgd(native_p4d_val(p4d));
146 pgd = pti_set_user_pgtbl((pgd_t *)p4dp, pgd);
147 WRITE_ONCE(*p4dp, native_make_p4d(native_pgd_val(pgd)));
148}
149
150static inline void native_p4d_clear(p4d_t *p4d)
151{
152 native_set_p4d(p4d, native_make_p4d(0));
153}
154
155static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
156{
157 WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd));
158}
159
160static inline void native_pgd_clear(pgd_t *pgd)
161{
162 native_set_pgd(pgd, native_make_pgd(0));
163}
164
165extern void sync_global_pgds(unsigned long start, unsigned long end);
166
167/*
168 * Conversion functions: convert a page and protection to a page entry,
169 * and a page entry and page directory to the page they refer to.
170 */
171
172/*
173 * Level 4 access.
174 */
175#define mk_kernel_pgd(address) __pgd((address) | _KERNPG_TABLE)
176
177/* PUD - Level3 access */
178
179/* PMD - Level 2 access */
180
181/* PTE - Level 1 access. */
182
183/* x86-64 always has all page tables mapped. */
184#define pte_offset_map(dir, address) pte_offset_kernel((dir), (address))
185#define pte_unmap(pte) ((void)(pte))/* NOP */
186
187/*
188 * Encode and de-code a swap entry
189 *
190 * | ... | 11| 10| 9|8|7|6|5| 4| 3|2| 1|0| <- bit number
191 * | ... |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names
192 * | TYPE (59-63) | ~OFFSET (9-58) |0|0|X|X| X| X|X|SD|0| <- swp entry
193 *
194 * G (8) is aliased and used as a PROT_NONE indicator for
195 * !present ptes. We need to start storing swap entries above
196 * there. We also need to avoid using A and D because of an
197 * erratum where they can be incorrectly set by hardware on
198 * non-present PTEs.
199 *
200 * SD (1) in swp entry is used to store soft dirty bit, which helps us
201 * remember soft dirty over page migration
202 *
203 * Bit 7 in swp entry should be 0 because pmd_present checks not only P,
204 * but also L and G.
205 *
206 * The offset is inverted by a binary not operation to make the high
207 * physical bits set.
208 */
209#define SWP_TYPE_BITS 5
210
211#define SWP_OFFSET_FIRST_BIT (_PAGE_BIT_PROTNONE + 1)
212
213/* We always extract/encode the offset by shifting it all the way up, and then down again */
214#define SWP_OFFSET_SHIFT (SWP_OFFSET_FIRST_BIT+SWP_TYPE_BITS)
215
216#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
217
218/* Extract the high bits for type */
219#define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS))
220
221/* Shift up (to get rid of type), then down to get value */
222#define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)
223
224/*
225 * Shift the offset up "too far" by TYPE bits, then down again
226 * The offset is inverted by a binary not operation to make the high
227 * physical bits set.
228 */
229#define __swp_entry(type, offset) ((swp_entry_t) { \
230 (~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
231 | ((unsigned long)(type) << (64-SWP_TYPE_BITS)) })
232
233#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val((pte)) })
234#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val((pmd)) })
235#define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val })
236#define __swp_entry_to_pmd(x) ((pmd_t) { .pmd = (x).val })
237
238extern int kern_addr_valid(unsigned long addr);
239extern void cleanup_highmap(void);
240
241#define HAVE_ARCH_UNMAPPED_AREA
242#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
243
244#define pgtable_cache_init() do { } while (0)
245#define check_pgt_cache() do { } while (0)
246
247#define PAGE_AGP PAGE_KERNEL_NOCACHE
248#define HAVE_PAGE_AGP 1
249
250/* fs/proc/kcore.c */
251#define kc_vaddr_to_offset(v) ((v) & __VIRTUAL_MASK)
252#define kc_offset_to_vaddr(o) ((o) | ~__VIRTUAL_MASK)
253
254#define __HAVE_ARCH_PTE_SAME
255
256#define vmemmap ((struct page *)VMEMMAP_START)
257
258extern void init_extra_mapping_uc(unsigned long phys, unsigned long size);
259extern void init_extra_mapping_wb(unsigned long phys, unsigned long size);
260
261#define gup_fast_permitted gup_fast_permitted
262static inline bool gup_fast_permitted(unsigned long start, int nr_pages)
263{
264 unsigned long len, end;
265
266 len = (unsigned long)nr_pages << PAGE_SHIFT;
267 end = start + len;
268 if (end < start)
269 return false;
270 if (end >> __VIRTUAL_MASK_SHIFT)
271 return false;
272 return true;
273}
274
275#include <asm/pgtable-invert.h>
276
277#endif /* !__ASSEMBLY__ */
278#endif /* _ASM_X86_PGTABLE_64_H */
279