xref: /linux/arch/powerpc/include/asm/pgtable.h (revision 2ba9268dd603d23e17643437b2246acb6844953b)
1 #ifndef _ASM_POWERPC_PGTABLE_H
2 #define _ASM_POWERPC_PGTABLE_H
3 #ifdef __KERNEL__
4 
5 #ifndef __ASSEMBLY__
6 #include <linux/mmdebug.h>
7 #include <linux/mmzone.h>
8 #include <asm/processor.h>		/* For TASK_SIZE */
9 #include <asm/mmu.h>
10 #include <asm/page.h>
11 
12 struct mm_struct;
13 
14 #endif /* !__ASSEMBLY__ */
15 
16 #if defined(CONFIG_PPC64)
17 #  include <asm/pgtable-ppc64.h>
18 #else
19 #  include <asm/pgtable-ppc32.h>
20 #endif
21 
22 /*
23  * We save the slot number & secondary bit in the second half of the
24  * PTE page. We use the 8 bytes per each pte entry.
25  */
26 #define PTE_PAGE_HIDX_OFFSET (PTRS_PER_PTE * 8)
27 
28 #ifndef __ASSEMBLY__
29 
30 #include <asm/tlbflush.h>
31 
32 /* Generic accessors to PTE bits */
33 static inline int pte_write(pte_t pte)
34 {	return (pte_val(pte) & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO; }
35 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
36 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
37 static inline int pte_special(pte_t pte)	{ return pte_val(pte) & _PAGE_SPECIAL; }
38 static inline int pte_none(pte_t pte)		{ return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }
39 static inline pgprot_t pte_pgprot(pte_t pte)	{ return __pgprot(pte_val(pte) & PAGE_PROT_BITS); }
40 
41 #ifdef CONFIG_NUMA_BALANCING
42 /*
43  * These work without NUMA balancing but the kernel does not care. See the
44  * comment in include/asm-generic/pgtable.h . On powerpc, this will only
45  * work for user pages and always return true for kernel pages.
46  */
47 static inline int pte_protnone(pte_t pte)
48 {
49 	return (pte_val(pte) &
50 		(_PAGE_PRESENT | _PAGE_USER)) == _PAGE_PRESENT;
51 }
52 
53 static inline int pmd_protnone(pmd_t pmd)
54 {
55 	return pte_protnone(pmd_pte(pmd));
56 }
57 #endif /* CONFIG_NUMA_BALANCING */
58 
59 static inline int pte_present(pte_t pte)
60 {
61 	return pte_val(pte) & _PAGE_PRESENT;
62 }
63 
64 /* Conversion functions: convert a page and protection to a page entry,
65  * and a page entry and page directory to the page they refer to.
66  *
67  * Even if PTEs can be unsigned long long, a PFN is always an unsigned
68  * long for now.
69  */
70 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) {
71 	return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) |
72 		     pgprot_val(pgprot)); }
73 static inline unsigned long pte_pfn(pte_t pte)	{
74 	return pte_val(pte) >> PTE_RPN_SHIFT; }
75 
76 /* Keep these as a macros to avoid include dependency mess */
77 #define pte_page(x)		pfn_to_page(pte_pfn(x))
78 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
79 
80 /* Generic modifiers for PTE bits */
81 static inline pte_t pte_wrprotect(pte_t pte) {
82 	pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE);
83 	pte_val(pte) |= _PAGE_RO; return pte; }
84 static inline pte_t pte_mkclean(pte_t pte) {
85 	pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; }
86 static inline pte_t pte_mkold(pte_t pte) {
87 	pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
88 static inline pte_t pte_mkwrite(pte_t pte) {
89 	pte_val(pte) &= ~_PAGE_RO;
90 	pte_val(pte) |= _PAGE_RW; return pte; }
91 static inline pte_t pte_mkdirty(pte_t pte) {
92 	pte_val(pte) |= _PAGE_DIRTY; return pte; }
93 static inline pte_t pte_mkyoung(pte_t pte) {
94 	pte_val(pte) |= _PAGE_ACCESSED; return pte; }
95 static inline pte_t pte_mkspecial(pte_t pte) {
96 	pte_val(pte) |= _PAGE_SPECIAL; return pte; }
97 static inline pte_t pte_mkhuge(pte_t pte) {
98 	return pte; }
99 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
100 {
101 	pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
102 	return pte;
103 }
104 
105 
106 /* Insert a PTE, top-level function is out of line. It uses an inline
107  * low level function in the respective pgtable-* files
108  */
109 extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
110 		       pte_t pte);
111 
112 /* This low level function performs the actual PTE insertion
113  * Setting the PTE depends on the MMU type and other factors. It's
114  * an horrible mess that I'm not going to try to clean up now but
115  * I'm keeping it in one place rather than spread around
116  */
117 static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
118 				pte_t *ptep, pte_t pte, int percpu)
119 {
120 #if defined(CONFIG_PPC_STD_MMU_32) && defined(CONFIG_SMP) && !defined(CONFIG_PTE_64BIT)
121 	/* First case is 32-bit Hash MMU in SMP mode with 32-bit PTEs. We use the
122 	 * helper pte_update() which does an atomic update. We need to do that
123 	 * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a
124 	 * per-CPU PTE such as a kmap_atomic, we do a simple update preserving
125 	 * the hash bits instead (ie, same as the non-SMP case)
126 	 */
127 	if (percpu)
128 		*ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
129 			      | (pte_val(pte) & ~_PAGE_HASHPTE));
130 	else
131 		pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte));
132 
133 #elif defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
134 	/* Second case is 32-bit with 64-bit PTE.  In this case, we
135 	 * can just store as long as we do the two halves in the right order
136 	 * with a barrier in between. This is possible because we take care,
137 	 * in the hash code, to pre-invalidate if the PTE was already hashed,
138 	 * which synchronizes us with any concurrent invalidation.
139 	 * In the percpu case, we also fallback to the simple update preserving
140 	 * the hash bits
141 	 */
142 	if (percpu) {
143 		*ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
144 			      | (pte_val(pte) & ~_PAGE_HASHPTE));
145 		return;
146 	}
147 #if _PAGE_HASHPTE != 0
148 	if (pte_val(*ptep) & _PAGE_HASHPTE)
149 		flush_hash_entry(mm, ptep, addr);
150 #endif
151 	__asm__ __volatile__("\
152 		stw%U0%X0 %2,%0\n\
153 		eieio\n\
154 		stw%U0%X0 %L2,%1"
155 	: "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
156 	: "r" (pte) : "memory");
157 
158 #elif defined(CONFIG_PPC_STD_MMU_32)
159 	/* Third case is 32-bit hash table in UP mode, we need to preserve
160 	 * the _PAGE_HASHPTE bit since we may not have invalidated the previous
161 	 * translation in the hash yet (done in a subsequent flush_tlb_xxx())
162 	 * and see we need to keep track that this PTE needs invalidating
163 	 */
164 	*ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
165 		      | (pte_val(pte) & ~_PAGE_HASHPTE));
166 
167 #else
168 	/* Anything else just stores the PTE normally. That covers all 64-bit
169 	 * cases, and 32-bit non-hash with 32-bit PTEs.
170 	 */
171 	*ptep = pte;
172 #endif
173 }
174 
175 
176 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
177 extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
178 				 pte_t *ptep, pte_t entry, int dirty);
179 
180 /*
181  * Macro to mark a page protection value as "uncacheable".
182  */
183 
184 #define _PAGE_CACHE_CTL	(_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \
185 			 _PAGE_WRITETHRU)
186 
187 #define pgprot_noncached(prot)	  (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
188 				            _PAGE_NO_CACHE | _PAGE_GUARDED))
189 
190 #define pgprot_noncached_wc(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
191 				            _PAGE_NO_CACHE))
192 
193 #define pgprot_cached(prot)       (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
194 				            _PAGE_COHERENT))
195 
196 #define pgprot_cached_wthru(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
197 				            _PAGE_COHERENT | _PAGE_WRITETHRU))
198 
199 #define pgprot_cached_noncoherent(prot) \
200 		(__pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL))
201 
202 #define pgprot_writecombine pgprot_noncached_wc
203 
204 struct file;
205 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
206 				     unsigned long size, pgprot_t vma_prot);
207 #define __HAVE_PHYS_MEM_ACCESS_PROT
208 
209 /*
210  * ZERO_PAGE is a global shared page that is always zero: used
211  * for zero-mapped memory areas etc..
212  */
213 extern unsigned long empty_zero_page[];
214 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
215 
216 extern pgd_t swapper_pg_dir[];
217 
218 void limit_zone_pfn(enum zone_type zone, unsigned long max_pfn);
219 int dma_pfn_limit_to_zone(u64 pfn_limit);
220 extern void paging_init(void);
221 
222 /*
223  * kern_addr_valid is intended to indicate whether an address is a valid
224  * kernel address.  Most 32-bit archs define it as always true (like this)
225  * but most 64-bit archs actually perform a test.  What should we do here?
226  */
227 #define kern_addr_valid(addr)	(1)
228 
229 #include <asm-generic/pgtable.h>
230 
231 
232 /*
233  * This gets called at the end of handling a page fault, when
234  * the kernel has put a new PTE into the page table for the process.
235  * We use it to ensure coherency between the i-cache and d-cache
236  * for the page which has just been mapped in.
237  * On machines which use an MMU hash table, we use this to put a
238  * corresponding HPTE into the hash table ahead of time, instead of
239  * waiting for the inevitable extra hash-table miss exception.
240  */
241 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
242 
243 extern int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
244 		       unsigned long end, int write,
245 		       struct page **pages, int *nr);
246 #ifndef CONFIG_TRANSPARENT_HUGEPAGE
247 #define pmd_large(pmd)		0
248 #define has_transparent_hugepage() 0
249 #endif
250 pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
251 				 unsigned *shift);
252 
253 static inline pte_t *lookup_linux_ptep(pgd_t *pgdir, unsigned long hva,
254 				     unsigned long *pte_sizep)
255 {
256 	pte_t *ptep;
257 	unsigned long ps = *pte_sizep;
258 	unsigned int shift;
259 
260 	ptep = find_linux_pte_or_hugepte(pgdir, hva, &shift);
261 	if (!ptep)
262 		return NULL;
263 	if (shift)
264 		*pte_sizep = 1ul << shift;
265 	else
266 		*pte_sizep = PAGE_SIZE;
267 
268 	if (ps > *pte_sizep)
269 		return NULL;
270 
271 	return ptep;
272 }
273 #endif /* __ASSEMBLY__ */
274 
275 #endif /* __KERNEL__ */
276 #endif /* _ASM_POWERPC_PGTABLE_H */
277