1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_PGTABLE_RADIX_H
3 #define _ASM_POWERPC_PGTABLE_RADIX_H
4 
5 #include <asm/asm-const.h>
6 
7 #ifndef __ASSEMBLY__
8 #include <asm/cmpxchg.h>
9 #endif
10 
11 #ifdef CONFIG_PPC_64K_PAGES
12 #include <asm/book3s/64/radix-64k.h>
13 #else
14 #include <asm/book3s/64/radix-4k.h>
15 #endif
16 
17 #ifndef __ASSEMBLY__
18 #include <asm/book3s/64/tlbflush-radix.h>
19 #include <asm/cpu_has_feature.h>
20 #endif
21 
22 /* An empty PTE can still have a R or C writeback */
23 #define RADIX_PTE_NONE_MASK		(_PAGE_DIRTY | _PAGE_ACCESSED)
24 
25 /* Bits to set in a RPMD/RPUD/RPGD */
26 #define RADIX_PMD_VAL_BITS		(0x8000000000000000UL | RADIX_PTE_INDEX_SIZE)
27 #define RADIX_PUD_VAL_BITS		(0x8000000000000000UL | RADIX_PMD_INDEX_SIZE)
28 #define RADIX_PGD_VAL_BITS		(0x8000000000000000UL | RADIX_PUD_INDEX_SIZE)
29 
30 /* Don't have anything in the reserved bits and leaf bits */
31 #define RADIX_PMD_BAD_BITS		0x60000000000000e0UL
32 #define RADIX_PUD_BAD_BITS		0x60000000000000e0UL
33 #define RADIX_PGD_BAD_BITS		0x60000000000000e0UL
34 
35 #define RADIX_PMD_SHIFT		(PAGE_SHIFT + RADIX_PTE_INDEX_SIZE)
36 #define RADIX_PUD_SHIFT		(RADIX_PMD_SHIFT + RADIX_PMD_INDEX_SIZE)
37 #define RADIX_PGD_SHIFT		(RADIX_PUD_SHIFT + RADIX_PUD_INDEX_SIZE)
38 /*
39  * Size of EA range mapped by our pagetables.
40  */
41 #define RADIX_PGTABLE_EADDR_SIZE (RADIX_PTE_INDEX_SIZE + RADIX_PMD_INDEX_SIZE +	\
42 			      RADIX_PUD_INDEX_SIZE + RADIX_PGD_INDEX_SIZE + PAGE_SHIFT)
43 #define RADIX_PGTABLE_RANGE (ASM_CONST(1) << RADIX_PGTABLE_EADDR_SIZE)
44 
45 /*
46  * We support 52 bit address space, Use top bit for kernel
47  * virtual mapping. Also make sure kernel fit in the top
48  * quadrant.
49  *
50  *           +------------------+
51  *           +------------------+  Kernel virtual map (0xc008000000000000)
52  *           |                  |
53  *           |                  |
54  *           |                  |
55  * 0b11......+------------------+  Kernel linear map (0xc....)
56  *           |                  |
57  *           |     2 quadrant   |
58  *           |                  |
59  * 0b10......+------------------+
60  *           |                  |
61  *           |    1 quadrant    |
62  *           |                  |
63  * 0b01......+------------------+
64  *           |                  |
65  *           |    0 quadrant    |
66  *           |                  |
67  * 0b00......+------------------+
68  *
69  *
70  * 3rd quadrant expanded:
71  * +------------------------------+
72  * |                              |
73  * |                              |
74  * |                              |
75  * +------------------------------+  Kernel vmemmap end (0xc010000000000000)
76  * |                              |
77  * |           512TB		  |
78  * |                              |
79  * +------------------------------+  Kernel IO map end/vmemap start
80  * |                              |
81  * |           512TB		  |
82  * |                              |
83  * +------------------------------+  Kernel vmap end/ IO map start
84  * |                              |
85  * |           512TB		  |
86  * |                              |
87  * +------------------------------+  Kernel virt start (0xc008000000000000)
88  * |                              |
89  * |                              |
90  * |                              |
91  * +------------------------------+  Kernel linear (0xc.....)
92  */
93 
94 #define RADIX_KERN_VIRT_START	ASM_CONST(0xc008000000000000)
95 /*
96  * 49 =  MAX_EA_BITS_PER_CONTEXT (hash specific). To make sure we pick
97  * the same value as hash.
98  */
99 #define RADIX_KERN_MAP_SIZE	(1UL << 49)
100 
101 #define RADIX_VMALLOC_START	RADIX_KERN_VIRT_START
102 #define RADIX_VMALLOC_SIZE	RADIX_KERN_MAP_SIZE
103 #define RADIX_VMALLOC_END	(RADIX_VMALLOC_START + RADIX_VMALLOC_SIZE)
104 
105 #define RADIX_KERN_IO_START	RADIX_VMALLOC_END
106 #define RADIX_KERN_IO_SIZE	RADIX_KERN_MAP_SIZE
107 #define RADIX_KERN_IO_END	(RADIX_KERN_IO_START + RADIX_KERN_IO_SIZE)
108 
109 #define RADIX_VMEMMAP_START	RADIX_KERN_IO_END
110 #define RADIX_VMEMMAP_SIZE	RADIX_KERN_MAP_SIZE
111 #define RADIX_VMEMMAP_END	(RADIX_VMEMMAP_START + RADIX_VMEMMAP_SIZE)
112 
113 #ifndef __ASSEMBLY__
114 #define RADIX_PTE_TABLE_SIZE	(sizeof(pte_t) << RADIX_PTE_INDEX_SIZE)
115 #define RADIX_PMD_TABLE_SIZE	(sizeof(pmd_t) << RADIX_PMD_INDEX_SIZE)
116 #define RADIX_PUD_TABLE_SIZE	(sizeof(pud_t) << RADIX_PUD_INDEX_SIZE)
117 #define RADIX_PGD_TABLE_SIZE	(sizeof(pgd_t) << RADIX_PGD_INDEX_SIZE)
118 
119 #ifdef CONFIG_STRICT_KERNEL_RWX
120 extern void radix__mark_rodata_ro(void);
121 extern void radix__mark_initmem_nx(void);
122 #endif
123 
124 extern void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
125 					 pte_t entry, unsigned long address,
126 					 int psize);
127 
128 extern void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
129 					   unsigned long addr, pte_t *ptep,
130 					   pte_t old_pte, pte_t pte);
131 
132 static inline unsigned long __radix_pte_update(pte_t *ptep, unsigned long clr,
133 					       unsigned long set)
134 {
135 	__be64 old_be, tmp_be;
136 
137 	__asm__ __volatile__(
138 	"1:	ldarx	%0,0,%3		# pte_update\n"
139 	"	andc	%1,%0,%5	\n"
140 	"	or	%1,%1,%4	\n"
141 	"	stdcx.	%1,0,%3		\n"
142 	"	bne-	1b"
143 	: "=&r" (old_be), "=&r" (tmp_be), "=m" (*ptep)
144 	: "r" (ptep), "r" (cpu_to_be64(set)), "r" (cpu_to_be64(clr))
145 	: "cc" );
146 
147 	return be64_to_cpu(old_be);
148 }
149 
150 static inline unsigned long radix__pte_update(struct mm_struct *mm,
151 					unsigned long addr,
152 					pte_t *ptep, unsigned long clr,
153 					unsigned long set,
154 					int huge)
155 {
156 	unsigned long old_pte;
157 
158 	old_pte = __radix_pte_update(ptep, clr, set);
159 	if (!huge)
160 		assert_pte_locked(mm, addr);
161 
162 	return old_pte;
163 }
164 
165 static inline pte_t radix__ptep_get_and_clear_full(struct mm_struct *mm,
166 						   unsigned long addr,
167 						   pte_t *ptep, int full)
168 {
169 	unsigned long old_pte;
170 
171 	if (full) {
172 		old_pte = pte_val(*ptep);
173 		*ptep = __pte(0);
174 	} else
175 		old_pte = radix__pte_update(mm, addr, ptep, ~0ul, 0, 0);
176 
177 	return __pte(old_pte);
178 }
179 
180 static inline int radix__pte_same(pte_t pte_a, pte_t pte_b)
181 {
182 	return ((pte_raw(pte_a) ^ pte_raw(pte_b)) == 0);
183 }
184 
185 static inline int radix__pte_none(pte_t pte)
186 {
187 	return (pte_val(pte) & ~RADIX_PTE_NONE_MASK) == 0;
188 }
189 
190 static inline void radix__set_pte_at(struct mm_struct *mm, unsigned long addr,
191 				 pte_t *ptep, pte_t pte, int percpu)
192 {
193 	*ptep = pte;
194 
195 	/*
196 	 * The architecture suggests a ptesync after setting the pte, which
197 	 * orders the store that updates the pte with subsequent page table
198 	 * walk accesses which may load the pte. Without this it may be
199 	 * possible for a subsequent access to result in spurious fault.
200 	 *
201 	 * This is not necessary for correctness, because a spurious fault
202 	 * is tolerated by the page fault handler, and this store will
203 	 * eventually be seen. In testing, there was no noticable increase
204 	 * in user faults on POWER9. Avoiding ptesync here is a significant
205 	 * win for things like fork. If a future microarchitecture benefits
206 	 * from ptesync, it should probably go into update_mmu_cache, rather
207 	 * than set_pte_at (which is used to set ptes unrelated to faults).
208 	 *
209 	 * Spurious faults to vmalloc region are not tolerated, so there is
210 	 * a ptesync in flush_cache_vmap.
211 	 */
212 }
213 
214 static inline int radix__pmd_bad(pmd_t pmd)
215 {
216 	return !!(pmd_val(pmd) & RADIX_PMD_BAD_BITS);
217 }
218 
219 static inline int radix__pmd_same(pmd_t pmd_a, pmd_t pmd_b)
220 {
221 	return ((pmd_raw(pmd_a) ^ pmd_raw(pmd_b)) == 0);
222 }
223 
224 static inline int radix__pud_bad(pud_t pud)
225 {
226 	return !!(pud_val(pud) & RADIX_PUD_BAD_BITS);
227 }
228 
229 
230 static inline int radix__pgd_bad(pgd_t pgd)
231 {
232 	return !!(pgd_val(pgd) & RADIX_PGD_BAD_BITS);
233 }
234 
235 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
236 
237 static inline int radix__pmd_trans_huge(pmd_t pmd)
238 {
239 	return (pmd_val(pmd) & (_PAGE_PTE | _PAGE_DEVMAP)) == _PAGE_PTE;
240 }
241 
242 static inline pmd_t radix__pmd_mkhuge(pmd_t pmd)
243 {
244 	return __pmd(pmd_val(pmd) | _PAGE_PTE);
245 }
246 
247 extern unsigned long radix__pmd_hugepage_update(struct mm_struct *mm, unsigned long addr,
248 					  pmd_t *pmdp, unsigned long clr,
249 					  unsigned long set);
250 extern pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma,
251 				  unsigned long address, pmd_t *pmdp);
252 extern void radix__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
253 					pgtable_t pgtable);
254 extern pgtable_t radix__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
255 extern pmd_t radix__pmdp_huge_get_and_clear(struct mm_struct *mm,
256 				      unsigned long addr, pmd_t *pmdp);
257 extern int radix__has_transparent_hugepage(void);
258 #endif
259 
260 extern int __meminit radix__vmemmap_create_mapping(unsigned long start,
261 					     unsigned long page_size,
262 					     unsigned long phys);
263 extern void radix__vmemmap_remove_mapping(unsigned long start,
264 				    unsigned long page_size);
265 
266 extern int radix__map_kernel_page(unsigned long ea, unsigned long pa,
267 				 pgprot_t flags, unsigned int psz);
268 
269 static inline unsigned long radix__get_tree_size(void)
270 {
271 	unsigned long rts_field;
272 	/*
273 	 * We support 52 bits, hence:
274 	 * bits 52 - 31 = 21, 0b10101
275 	 * RTS encoding details
276 	 * bits 0 - 3 of rts -> bits 6 - 8 unsigned long
277 	 * bits 4 - 5 of rts -> bits 62 - 63 of unsigned long
278 	 */
279 	rts_field = (0x5UL << 5); /* 6 - 8 bits */
280 	rts_field |= (0x2UL << 61);
281 
282 	return rts_field;
283 }
284 
285 #ifdef CONFIG_MEMORY_HOTPLUG
286 int radix__create_section_mapping(unsigned long start, unsigned long end, int nid);
287 int radix__remove_section_mapping(unsigned long start, unsigned long end);
288 #endif /* CONFIG_MEMORY_HOTPLUG */
289 #endif /* __ASSEMBLY__ */
290 #endif
291