1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_BOOK3S_64_HASH_H
3 #define _ASM_POWERPC_BOOK3S_64_HASH_H
4 #ifdef __KERNEL__
5 
6 #include <asm/asm-const.h>
7 #include <asm/book3s/64/slice.h>
8 
9 /*
10  * Common bits between 4K and 64K pages in a linux-style PTE.
11  * Additional bits may be defined in pgtable-hash64-*.h
12  *
13  */
14 #define H_PTE_NONE_MASK		_PAGE_HPTEFLAGS
15 
16 #ifdef CONFIG_PPC_64K_PAGES
17 #include <asm/book3s/64/hash-64k.h>
18 #else
19 #include <asm/book3s/64/hash-4k.h>
20 #endif
21 
22 #define H_PTRS_PER_PTE		(1 << H_PTE_INDEX_SIZE)
23 #define H_PTRS_PER_PMD		(1 << H_PMD_INDEX_SIZE)
24 #define H_PTRS_PER_PUD		(1 << H_PUD_INDEX_SIZE)
25 
26 /* Bits to set in a PMD/PUD/PGD entry valid bit*/
27 #define HASH_PMD_VAL_BITS		(0x8000000000000000UL)
28 #define HASH_PUD_VAL_BITS		(0x8000000000000000UL)
29 #define HASH_PGD_VAL_BITS		(0x8000000000000000UL)
30 
31 /*
32  * Size of EA range mapped by our pagetables.
33  */
34 #define H_PGTABLE_EADDR_SIZE	(H_PTE_INDEX_SIZE + H_PMD_INDEX_SIZE + \
35 				 H_PUD_INDEX_SIZE + H_PGD_INDEX_SIZE + PAGE_SHIFT)
36 #define H_PGTABLE_RANGE		(ASM_CONST(1) << H_PGTABLE_EADDR_SIZE)
37 /*
38  * Top 2 bits are ignored in page table walk.
39  */
40 #define EA_MASK			(~(0xcUL << 60))
41 
42 /*
43  * We store the slot details in the second half of page table.
44  * Increase the pud level table so that hugetlb ptes can be stored
45  * at pud level.
46  */
47 #if defined(CONFIG_HUGETLB_PAGE) &&  defined(CONFIG_PPC_64K_PAGES)
48 #define H_PUD_CACHE_INDEX	(H_PUD_INDEX_SIZE + 1)
49 #else
50 #define H_PUD_CACHE_INDEX	(H_PUD_INDEX_SIZE)
51 #endif
52 
53 /*
54  * +------------------------------+
55  * |                              |
56  * |                              |
57  * |                              |
58  * +------------------------------+  Kernel virtual map end (0xc00e000000000000)
59  * |                              |
60  * |                              |
61  * |      512TB/16TB of vmemmap   |
62  * |                              |
63  * |                              |
64  * +------------------------------+  Kernel vmemmap  start
65  * |                              |
66  * |      512TB/16TB of IO map    |
67  * |                              |
68  * +------------------------------+  Kernel IO map start
69  * |                              |
70  * |      512TB/16TB of vmap      |
71  * |                              |
72  * +------------------------------+  Kernel virt start (0xc008000000000000)
73  * |                              |
74  * |                              |
75  * |                              |
76  * +------------------------------+  Kernel linear (0xc.....)
77  */
78 
79 #define H_VMALLOC_START		H_KERN_VIRT_START
80 #define H_VMALLOC_SIZE		H_KERN_MAP_SIZE
81 #define H_VMALLOC_END		(H_VMALLOC_START + H_VMALLOC_SIZE)
82 
83 #define H_KERN_IO_START		H_VMALLOC_END
84 #define H_KERN_IO_SIZE		H_KERN_MAP_SIZE
85 #define H_KERN_IO_END		(H_KERN_IO_START + H_KERN_IO_SIZE)
86 
87 #define H_VMEMMAP_START		H_KERN_IO_END
88 #define H_VMEMMAP_SIZE		H_KERN_MAP_SIZE
89 #define H_VMEMMAP_END		(H_VMEMMAP_START + H_VMEMMAP_SIZE)
90 
91 #define NON_LINEAR_REGION_ID(ea)	((((unsigned long)ea - H_KERN_VIRT_START) >> REGION_SHIFT) + 2)
92 
93 /*
94  * Region IDs
95  */
96 #define USER_REGION_ID		0
97 #define LINEAR_MAP_REGION_ID	1
98 #define VMALLOC_REGION_ID	NON_LINEAR_REGION_ID(H_VMALLOC_START)
99 #define IO_REGION_ID		NON_LINEAR_REGION_ID(H_KERN_IO_START)
100 #define VMEMMAP_REGION_ID	NON_LINEAR_REGION_ID(H_VMEMMAP_START)
101 #define INVALID_REGION_ID	(VMEMMAP_REGION_ID + 1)
102 
103 /*
104  * Defines the address of the vmemap area, in its own region on
105  * hash table CPUs.
106  */
107 
108 /* PTEIDX nibble */
109 #define _PTEIDX_SECONDARY	0x8
110 #define _PTEIDX_GROUP_IX	0x7
111 
112 #define H_PMD_BAD_BITS		(PTE_TABLE_SIZE-1)
113 #define H_PUD_BAD_BITS		(PMD_TABLE_SIZE-1)
114 
115 #ifndef __ASSEMBLY__
get_region_id(unsigned long ea)116 static inline int get_region_id(unsigned long ea)
117 {
118 	int region_id;
119 	int id = (ea >> 60UL);
120 
121 	if (id == 0)
122 		return USER_REGION_ID;
123 
124 	if (id != (PAGE_OFFSET >> 60))
125 		return INVALID_REGION_ID;
126 
127 	if (ea < H_KERN_VIRT_START)
128 		return LINEAR_MAP_REGION_ID;
129 
130 	BUILD_BUG_ON(NON_LINEAR_REGION_ID(H_VMALLOC_START) != 2);
131 
132 	region_id = NON_LINEAR_REGION_ID(ea);
133 	return region_id;
134 }
135 
hash__pmd_same(pmd_t pmd_a,pmd_t pmd_b)136 static inline int hash__pmd_same(pmd_t pmd_a, pmd_t pmd_b)
137 {
138 	return (((pmd_raw(pmd_a) ^ pmd_raw(pmd_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0);
139 }
140 
141 #define	hash__pmd_bad(pmd)		(pmd_val(pmd) & H_PMD_BAD_BITS)
142 
143 /*
144  * pud comparison that will work with both pte and page table pointer.
145  */
hash__pud_same(pud_t pud_a,pud_t pud_b)146 static inline int hash__pud_same(pud_t pud_a, pud_t pud_b)
147 {
148 	return (((pud_raw(pud_a) ^ pud_raw(pud_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0);
149 }
150 #define	hash__pud_bad(pud)		(pud_val(pud) & H_PUD_BAD_BITS)
151 
hash__p4d_bad(p4d_t p4d)152 static inline int hash__p4d_bad(p4d_t p4d)
153 {
154 	return (p4d_val(p4d) == 0);
155 }
156 #ifdef CONFIG_STRICT_KERNEL_RWX
157 extern void hash__mark_rodata_ro(void);
158 extern void hash__mark_initmem_nx(void);
159 #endif
160 
161 extern void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
162 			    pte_t *ptep, unsigned long pte, int huge);
163 unsigned long htab_convert_pte_flags(unsigned long pteflags, unsigned long flags);
164 /* Atomic PTE updates */
hash__pte_update_one(pte_t * ptep,unsigned long clr,unsigned long set)165 static inline unsigned long hash__pte_update_one(pte_t *ptep, unsigned long clr,
166 						 unsigned long set)
167 {
168 	__be64 old_be, tmp_be;
169 
170 	__asm__ __volatile__(
171 	"1:	ldarx	%0,0,%3		# pte_update\n\
172 	and.	%1,%0,%6\n\
173 	bne-	1b \n\
174 	andc	%1,%0,%4 \n\
175 	or	%1,%1,%7\n\
176 	stdcx.	%1,0,%3 \n\
177 	bne-	1b"
178 	: "=&r" (old_be), "=&r" (tmp_be), "=m" (*ptep)
179 	: "r" (ptep), "r" (cpu_to_be64(clr)), "m" (*ptep),
180 	  "r" (cpu_to_be64(H_PAGE_BUSY)), "r" (cpu_to_be64(set))
181 	: "cc" );
182 
183 	return be64_to_cpu(old_be);
184 }
185 
hash__pte_update(struct mm_struct * mm,unsigned long addr,pte_t * ptep,unsigned long clr,unsigned long set,int huge)186 static inline unsigned long hash__pte_update(struct mm_struct *mm,
187 					 unsigned long addr,
188 					 pte_t *ptep, unsigned long clr,
189 					 unsigned long set,
190 					 int huge)
191 {
192 	unsigned long old;
193 
194 	old = hash__pte_update_one(ptep, clr, set);
195 
196 	if (IS_ENABLED(CONFIG_PPC_4K_PAGES) && huge) {
197 		unsigned int psize = get_slice_psize(mm, addr);
198 		int nb, i;
199 
200 		if (psize == MMU_PAGE_16M)
201 			nb = SZ_16M / PMD_SIZE;
202 		else if (psize == MMU_PAGE_16G)
203 			nb = SZ_16G / PUD_SIZE;
204 		else
205 			nb = 1;
206 
207 		WARN_ON_ONCE(nb == 1);	/* Should never happen */
208 
209 		for (i = 1; i < nb; i++)
210 			hash__pte_update_one(ptep + i, clr, set);
211 	}
212 	/* huge pages use the old page table lock */
213 	if (!huge)
214 		assert_pte_locked(mm, addr);
215 
216 	if (old & H_PAGE_HASHPTE)
217 		hpte_need_flush(mm, addr, ptep, old, huge);
218 
219 	return old;
220 }
221 
222 /* Set the dirty and/or accessed bits atomically in a linux PTE, this
223  * function doesn't need to flush the hash entry
224  */
hash__ptep_set_access_flags(pte_t * ptep,pte_t entry)225 static inline void hash__ptep_set_access_flags(pte_t *ptep, pte_t entry)
226 {
227 	__be64 old, tmp, val, mask;
228 
229 	mask = cpu_to_be64(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_READ | _PAGE_WRITE |
230 			   _PAGE_EXEC | _PAGE_SOFT_DIRTY);
231 
232 	val = pte_raw(entry) & mask;
233 
234 	__asm__ __volatile__(
235 	"1:	ldarx	%0,0,%4\n\
236 		and.	%1,%0,%6\n\
237 		bne-	1b \n\
238 		or	%0,%3,%0\n\
239 		stdcx.	%0,0,%4\n\
240 		bne-	1b"
241 	:"=&r" (old), "=&r" (tmp), "=m" (*ptep)
242 	:"r" (val), "r" (ptep), "m" (*ptep), "r" (cpu_to_be64(H_PAGE_BUSY))
243 	:"cc");
244 }
245 
hash__pte_same(pte_t pte_a,pte_t pte_b)246 static inline int hash__pte_same(pte_t pte_a, pte_t pte_b)
247 {
248 	return (((pte_raw(pte_a) ^ pte_raw(pte_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0);
249 }
250 
hash__pte_none(pte_t pte)251 static inline int hash__pte_none(pte_t pte)
252 {
253 	return (pte_val(pte) & ~H_PTE_NONE_MASK) == 0;
254 }
255 
256 unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift,
257 		int ssize, real_pte_t rpte, unsigned int subpg_index);
258 
259 /* This low level function performs the actual PTE insertion
260  * Setting the PTE depends on the MMU type and other factors. It's
261  * an horrible mess that I'm not going to try to clean up now but
262  * I'm keeping it in one place rather than spread around
263  */
hash__set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t pte,int percpu)264 static inline void hash__set_pte_at(struct mm_struct *mm, unsigned long addr,
265 				  pte_t *ptep, pte_t pte, int percpu)
266 {
267 	/*
268 	 * Anything else just stores the PTE normally. That covers all 64-bit
269 	 * cases, and 32-bit non-hash with 32-bit PTEs.
270 	 */
271 	*ptep = pte;
272 }
273 
274 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
275 extern void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr,
276 				   pmd_t *pmdp, unsigned long old_pmd);
277 #else
hpte_do_hugepage_flush(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp,unsigned long old_pmd)278 static inline void hpte_do_hugepage_flush(struct mm_struct *mm,
279 					  unsigned long addr, pmd_t *pmdp,
280 					  unsigned long old_pmd)
281 {
282 	WARN(1, "%s called with THP disabled\n", __func__);
283 }
284 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
285 
286 
287 int hash__map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot);
288 extern int __meminit hash__vmemmap_create_mapping(unsigned long start,
289 					      unsigned long page_size,
290 					      unsigned long phys);
291 extern void hash__vmemmap_remove_mapping(unsigned long start,
292 				     unsigned long page_size);
293 
294 int hash__create_section_mapping(unsigned long start, unsigned long end,
295 				 int nid, pgprot_t prot);
296 int hash__remove_section_mapping(unsigned long start, unsigned long end);
297 
298 #endif /* !__ASSEMBLY__ */
299 #endif /* __KERNEL__ */
300 #endif /* _ASM_POWERPC_BOOK3S_64_HASH_H */
301