1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_NOHASH_64_PGTABLE_H
3 #define _ASM_POWERPC_NOHASH_64_PGTABLE_H
4 /*
5  * This file contains the functions and defines necessary to modify and use
6  * the ppc64 non-hashed page table.
7  */
8 
9 #include <linux/sizes.h>
10 
11 #include <asm/nohash/64/pgtable-4k.h>
12 #include <asm/barrier.h>
13 #include <asm/asm-const.h>
14 
15 /*
16  * Size of EA range mapped by our pagetables.
17  */
18 #define PGTABLE_EADDR_SIZE (PTE_INDEX_SIZE + PMD_INDEX_SIZE + \
19 			    PUD_INDEX_SIZE + PGD_INDEX_SIZE + PAGE_SHIFT)
20 #define PGTABLE_RANGE (ASM_CONST(1) << PGTABLE_EADDR_SIZE)
21 
22 #define PMD_CACHE_INDEX	PMD_INDEX_SIZE
23 #define PUD_CACHE_INDEX PUD_INDEX_SIZE
24 
25 /*
26  * Define the address range of the kernel non-linear virtual area
27  */
28 #define KERN_VIRT_START ASM_CONST(0xc000100000000000)
29 #define KERN_VIRT_SIZE	ASM_CONST(0x0000100000000000)
30 
31 /*
32  * The vmalloc space starts at the beginning of that region, and
33  * occupies a quarter of it on Book3E
34  * (we keep a quarter for the virtual memmap)
35  */
36 #define VMALLOC_START	KERN_VIRT_START
37 #define VMALLOC_SIZE	(KERN_VIRT_SIZE >> 2)
38 #define VMALLOC_END	(VMALLOC_START + VMALLOC_SIZE)
39 
40 /*
41  * The third quarter of the kernel virtual space is used for IO mappings,
42  * it's itself carved into the PIO region (ISA and PHB IO space) and
43  * the ioremap space
44  *
45  *  ISA_IO_BASE = KERN_IO_START, 64K reserved area
46  *  PHB_IO_BASE = ISA_IO_BASE + 64K to ISA_IO_BASE + 2G, PHB IO spaces
47  * IOREMAP_BASE = ISA_IO_BASE + 2G to KERN_IO_START + KERN_IO_SIZE
48  */
49 #define KERN_IO_START	(KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))
50 #define KERN_IO_SIZE	(KERN_VIRT_SIZE >> 2)
51 #define FULL_IO_SIZE	0x80000000ul
52 #define  ISA_IO_BASE	(KERN_IO_START)
53 #define  ISA_IO_END	(KERN_IO_START + 0x10000ul)
54 #define  PHB_IO_BASE	(ISA_IO_END)
55 #define  PHB_IO_END	(KERN_IO_START + FULL_IO_SIZE)
56 #define IOREMAP_BASE	(PHB_IO_END)
57 #define IOREMAP_START	(ioremap_bot)
58 #define IOREMAP_END	(KERN_IO_START + KERN_IO_SIZE - FIXADDR_SIZE)
59 #define FIXADDR_SIZE	SZ_32M
60 
61 /*
62  * Defines the address of the vmemap area, in its own region on
63  * after the vmalloc space on Book3E
64  */
65 #define VMEMMAP_BASE		VMALLOC_END
66 #define VMEMMAP_END		KERN_IO_START
67 #define vmemmap			((struct page *)VMEMMAP_BASE)
68 
69 
70 /*
71  * Include the PTE bits definitions
72  */
73 #include <asm/nohash/pte-e500.h>
74 
75 #define PTE_RPN_MASK	(~((1UL << PTE_RPN_SHIFT) - 1))
76 
77 /*
78  * _PAGE_CHG_MASK masks of bits that are to be preserved across
79  * pgprot changes.
80  */
81 #define _PAGE_CHG_MASK	(PTE_RPN_MASK | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SPECIAL)
82 
83 #define H_PAGE_4K_PFN 0
84 
85 #ifndef __ASSEMBLY__
86 /* pte_clear moved to later in this file */
87 
88 static inline pte_t pte_mkwrite(pte_t pte)
89 {
90 	return __pte(pte_val(pte) | _PAGE_RW);
91 }
92 
93 static inline pte_t pte_mkdirty(pte_t pte)
94 {
95 	return __pte(pte_val(pte) | _PAGE_DIRTY);
96 }
97 
98 static inline pte_t pte_mkyoung(pte_t pte)
99 {
100 	return __pte(pte_val(pte) | _PAGE_ACCESSED);
101 }
102 
103 static inline pte_t pte_wrprotect(pte_t pte)
104 {
105 	return __pte(pte_val(pte) & ~_PAGE_RW);
106 }
107 
108 #define PMD_BAD_BITS		(PTE_TABLE_SIZE-1)
109 #define PUD_BAD_BITS		(PMD_TABLE_SIZE-1)
110 
111 static inline void pmd_set(pmd_t *pmdp, unsigned long val)
112 {
113 	*pmdp = __pmd(val);
114 }
115 
116 static inline void pmd_clear(pmd_t *pmdp)
117 {
118 	*pmdp = __pmd(0);
119 }
120 
121 static inline pte_t pmd_pte(pmd_t pmd)
122 {
123 	return __pte(pmd_val(pmd));
124 }
125 
126 #define pmd_none(pmd)		(!pmd_val(pmd))
127 #define	pmd_bad(pmd)		(!is_kernel_addr(pmd_val(pmd)) \
128 				 || (pmd_val(pmd) & PMD_BAD_BITS))
129 #define	pmd_present(pmd)	(!pmd_none(pmd))
130 #define pmd_page_vaddr(pmd)	(pmd_val(pmd) & ~PMD_MASKED_BITS)
131 extern struct page *pmd_page(pmd_t pmd);
132 #define pmd_pfn(pmd)		(page_to_pfn(pmd_page(pmd)))
133 
134 static inline void pud_set(pud_t *pudp, unsigned long val)
135 {
136 	*pudp = __pud(val);
137 }
138 
139 static inline void pud_clear(pud_t *pudp)
140 {
141 	*pudp = __pud(0);
142 }
143 
144 #define pud_none(pud)		(!pud_val(pud))
145 #define	pud_bad(pud)		(!is_kernel_addr(pud_val(pud)) \
146 				 || (pud_val(pud) & PUD_BAD_BITS))
147 #define pud_present(pud)	(pud_val(pud) != 0)
148 
149 static inline pmd_t *pud_pgtable(pud_t pud)
150 {
151 	return (pmd_t *)(pud_val(pud) & ~PUD_MASKED_BITS);
152 }
153 
154 extern struct page *pud_page(pud_t pud);
155 
156 static inline pte_t pud_pte(pud_t pud)
157 {
158 	return __pte(pud_val(pud));
159 }
160 
161 static inline pud_t pte_pud(pte_t pte)
162 {
163 	return __pud(pte_val(pte));
164 }
165 #define pud_write(pud)		pte_write(pud_pte(pud))
166 #define p4d_write(pgd)		pte_write(p4d_pte(p4d))
167 
168 static inline void p4d_set(p4d_t *p4dp, unsigned long val)
169 {
170 	*p4dp = __p4d(val);
171 }
172 
173 /* Atomic PTE updates */
174 static inline unsigned long pte_update(struct mm_struct *mm,
175 				       unsigned long addr,
176 				       pte_t *ptep, unsigned long clr,
177 				       unsigned long set,
178 				       int huge)
179 {
180 	unsigned long old = pte_val(*ptep);
181 	*ptep = __pte((old & ~clr) | set);
182 
183 	/* huge pages use the old page table lock */
184 	if (!huge)
185 		assert_pte_locked(mm, addr);
186 
187 	return old;
188 }
189 
190 static inline int pte_young(pte_t pte)
191 {
192 	return pte_val(pte) & _PAGE_ACCESSED;
193 }
194 
195 static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
196 					      unsigned long addr, pte_t *ptep)
197 {
198 	unsigned long old;
199 
200 	if (pte_young(*ptep))
201 		return 0;
202 	old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
203 	return (old & _PAGE_ACCESSED) != 0;
204 }
205 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
206 #define ptep_test_and_clear_young(__vma, __addr, __ptep)		   \
207 ({									   \
208 	int __r;							   \
209 	__r = __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep); \
210 	__r;								   \
211 })
212 
213 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
214 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
215 				      pte_t *ptep)
216 {
217 
218 	if ((pte_val(*ptep) & _PAGE_RW) == 0)
219 		return;
220 
221 	pte_update(mm, addr, ptep, _PAGE_RW, 0, 0);
222 }
223 
224 #define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT
225 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
226 					   unsigned long addr, pte_t *ptep)
227 {
228 	if ((pte_val(*ptep) & _PAGE_RW) == 0)
229 		return;
230 
231 	pte_update(mm, addr, ptep, _PAGE_RW, 0, 1);
232 }
233 
234 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
235 #define ptep_clear_flush_young(__vma, __address, __ptep)		\
236 ({									\
237 	int __young = __ptep_test_and_clear_young((__vma)->vm_mm, __address, \
238 						  __ptep);		\
239 	__young;							\
240 })
241 
242 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
243 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
244 				       unsigned long addr, pte_t *ptep)
245 {
246 	unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0, 0);
247 	return __pte(old);
248 }
249 
250 static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
251 			     pte_t * ptep)
252 {
253 	pte_update(mm, addr, ptep, ~0UL, 0, 0);
254 }
255 
256 
257 /* Set the dirty and/or accessed bits atomically in a linux PTE */
258 static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
259 					   pte_t *ptep, pte_t entry,
260 					   unsigned long address,
261 					   int psize)
262 {
263 	unsigned long bits = pte_val(entry) &
264 		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
265 
266 	unsigned long old = pte_val(*ptep);
267 	*ptep = __pte(old | bits);
268 
269 	flush_tlb_page(vma, address);
270 }
271 
272 #define pte_ERROR(e) \
273 	pr_err("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
274 #define pmd_ERROR(e) \
275 	pr_err("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
276 #define pgd_ERROR(e) \
277 	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
278 
279 /*
280  * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
281  * are !pte_none() && !pte_present().
282  *
283  * Format of swap PTEs:
284  *
285  *                         1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
286  *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
287  *   <-------------------------- offset ----------------------------
288  *
289  *   3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 5 5 6 6 6 6
290  *   2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
291  *   --------------> <----------- zero ------------> E < type -> 0 0
292  *
293  * E is the exclusive marker that is not stored in swap entries.
294  */
295 #define MAX_SWAPFILES_CHECK() do { \
296 	BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS); \
297 	} while (0)
298 
299 #define SWP_TYPE_BITS 5
300 #define __swp_type(x)		(((x).val >> 2) \
301 				& ((1UL << SWP_TYPE_BITS) - 1))
302 #define __swp_offset(x)		((x).val >> PTE_RPN_SHIFT)
303 #define __swp_entry(type, offset)	((swp_entry_t) { \
304 					(((type) & 0x1f) << 2) \
305 					| ((offset) << PTE_RPN_SHIFT) })
306 
307 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val((pte)) })
308 #define __swp_entry_to_pte(x)		__pte((x).val)
309 
310 /* We borrow MSB 56 (LSB 7) to store the exclusive marker in swap PTEs. */
311 #define _PAGE_SWP_EXCLUSIVE	0x80
312 
313 int map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot);
314 void unmap_kernel_page(unsigned long va);
315 extern int __meminit vmemmap_create_mapping(unsigned long start,
316 					    unsigned long page_size,
317 					    unsigned long phys);
318 extern void vmemmap_remove_mapping(unsigned long start,
319 				   unsigned long page_size);
320 void __patch_exception(int exc, unsigned long addr);
321 #define patch_exception(exc, name) do { \
322 	extern unsigned int name; \
323 	__patch_exception((exc), (unsigned long)&name); \
324 } while (0)
325 
326 #endif /* __ASSEMBLY__ */
327 
328 #endif /* _ASM_POWERPC_NOHASH_64_PGTABLE_H */
329