1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_POWERPC_NOHASH_PGTABLE_H 3 #define _ASM_POWERPC_NOHASH_PGTABLE_H 4 5 #if defined(CONFIG_PPC64) 6 #include <asm/nohash/64/pgtable.h> 7 #else 8 #include <asm/nohash/32/pgtable.h> 9 #endif 10 11 /* Permission masks used for kernel mappings */ 12 #define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW) 13 #define PAGE_KERNEL_NC __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | _PAGE_NO_CACHE) 14 #define PAGE_KERNEL_NCG __pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \ 15 _PAGE_NO_CACHE | _PAGE_GUARDED) 16 #define PAGE_KERNEL_X __pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX) 17 #define PAGE_KERNEL_RO __pgprot(_PAGE_BASE | _PAGE_KERNEL_RO) 18 #define PAGE_KERNEL_ROX __pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX) 19 20 /* 21 * Protection used for kernel text. We want the debuggers to be able to 22 * set breakpoints anywhere, so don't write protect the kernel text 23 * on platforms where such control is possible. 24 */ 25 #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH) ||\ 26 defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE) 27 #define PAGE_KERNEL_TEXT PAGE_KERNEL_X 28 #else 29 #define PAGE_KERNEL_TEXT PAGE_KERNEL_ROX 30 #endif 31 32 /* Make modules code happy. We don't set RO yet */ 33 #define PAGE_KERNEL_EXEC PAGE_KERNEL_X 34 35 /* Advertise special mapping type for AGP */ 36 #define PAGE_AGP (PAGE_KERNEL_NC) 37 #define HAVE_PAGE_AGP 38 39 #ifndef __ASSEMBLY__ 40 41 /* Generic accessors to PTE bits */ 42 #ifndef pte_write 43 static inline int pte_write(pte_t pte) 44 { 45 return pte_val(pte) & _PAGE_RW; 46 } 47 #endif 48 static inline int pte_read(pte_t pte) { return 1; } 49 static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } 50 static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; } 51 static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; } 52 static inline bool pte_hashpte(pte_t pte) { return false; } 53 static inline bool pte_ci(pte_t pte) { return pte_val(pte) & _PAGE_NO_CACHE; } 54 static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; } 55 56 #ifdef CONFIG_NUMA_BALANCING 57 /* 58 * These work without NUMA balancing but the kernel does not care. See the 59 * comment in include/asm-generic/pgtable.h . On powerpc, this will only 60 * work for user pages and always return true for kernel pages. 61 */ 62 static inline int pte_protnone(pte_t pte) 63 { 64 return pte_present(pte) && !pte_user(pte); 65 } 66 67 static inline int pmd_protnone(pmd_t pmd) 68 { 69 return pte_protnone(pmd_pte(pmd)); 70 } 71 #endif /* CONFIG_NUMA_BALANCING */ 72 73 static inline int pte_present(pte_t pte) 74 { 75 return pte_val(pte) & _PAGE_PRESENT; 76 } 77 78 static inline bool pte_hw_valid(pte_t pte) 79 { 80 return pte_val(pte) & _PAGE_PRESENT; 81 } 82 83 /* 84 * Don't just check for any non zero bits in __PAGE_USER, since for book3e 85 * and PTE_64BIT, PAGE_KERNEL_X contains _PAGE_BAP_SR which is also in 86 * _PAGE_USER. Need to explicitly match _PAGE_BAP_UR bit in that case too. 87 */ 88 #ifndef pte_user 89 static inline bool pte_user(pte_t pte) 90 { 91 return (pte_val(pte) & _PAGE_USER) == _PAGE_USER; 92 } 93 #endif 94 95 /* 96 * We only find page table entry in the last level 97 * Hence no need for other accessors 98 */ 99 #define pte_access_permitted pte_access_permitted 100 static inline bool pte_access_permitted(pte_t pte, bool write) 101 { 102 /* 103 * A read-only access is controlled by _PAGE_USER bit. 104 * We have _PAGE_READ set for WRITE and EXECUTE 105 */ 106 if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte)) 107 return false; 108 109 if (write && !pte_write(pte)) 110 return false; 111 112 return true; 113 } 114 115 /* Conversion functions: convert a page and protection to a page entry, 116 * and a page entry and page directory to the page they refer to. 117 * 118 * Even if PTEs can be unsigned long long, a PFN is always an unsigned 119 * long for now. 120 */ 121 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot) { 122 return __pte(((pte_basic_t)(pfn) << PTE_RPN_SHIFT) | 123 pgprot_val(pgprot)); } 124 static inline unsigned long pte_pfn(pte_t pte) { 125 return pte_val(pte) >> PTE_RPN_SHIFT; } 126 127 /* Generic modifiers for PTE bits */ 128 static inline pte_t pte_exprotect(pte_t pte) 129 { 130 return __pte(pte_val(pte) & ~_PAGE_EXEC); 131 } 132 133 #ifndef pte_mkclean 134 static inline pte_t pte_mkclean(pte_t pte) 135 { 136 return __pte(pte_val(pte) & ~_PAGE_DIRTY); 137 } 138 #endif 139 140 static inline pte_t pte_mkold(pte_t pte) 141 { 142 return __pte(pte_val(pte) & ~_PAGE_ACCESSED); 143 } 144 145 static inline pte_t pte_mkpte(pte_t pte) 146 { 147 return pte; 148 } 149 150 static inline pte_t pte_mkspecial(pte_t pte) 151 { 152 return __pte(pte_val(pte) | _PAGE_SPECIAL); 153 } 154 155 #ifndef pte_mkhuge 156 static inline pte_t pte_mkhuge(pte_t pte) 157 { 158 return __pte(pte_val(pte)); 159 } 160 #endif 161 162 #ifndef pte_mkprivileged 163 static inline pte_t pte_mkprivileged(pte_t pte) 164 { 165 return __pte(pte_val(pte) & ~_PAGE_USER); 166 } 167 #endif 168 169 #ifndef pte_mkuser 170 static inline pte_t pte_mkuser(pte_t pte) 171 { 172 return __pte(pte_val(pte) | _PAGE_USER); 173 } 174 #endif 175 176 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 177 { 178 return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)); 179 } 180 181 /* Insert a PTE, top-level function is out of line. It uses an inline 182 * low level function in the respective pgtable-* files 183 */ 184 extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, 185 pte_t pte); 186 187 /* This low level function performs the actual PTE insertion 188 * Setting the PTE depends on the MMU type and other factors. It's 189 * an horrible mess that I'm not going to try to clean up now but 190 * I'm keeping it in one place rather than spread around 191 */ 192 static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, 193 pte_t *ptep, pte_t pte, int percpu) 194 { 195 /* Second case is 32-bit with 64-bit PTE. In this case, we 196 * can just store as long as we do the two halves in the right order 197 * with a barrier in between. 198 * In the percpu case, we also fallback to the simple update 199 */ 200 if (IS_ENABLED(CONFIG_PPC32) && IS_ENABLED(CONFIG_PTE_64BIT) && !percpu) { 201 __asm__ __volatile__("\ 202 stw%U0%X0 %2,%0\n\ 203 eieio\n\ 204 stw%U0%X0 %L2,%1" 205 : "=m" (*ptep), "=m" (*((unsigned char *)ptep+4)) 206 : "r" (pte) : "memory"); 207 return; 208 } 209 /* Anything else just stores the PTE normally. That covers all 64-bit 210 * cases, and 32-bit non-hash with 32-bit PTEs. 211 */ 212 *ptep = pte; 213 214 /* 215 * With hardware tablewalk, a sync is needed to ensure that 216 * subsequent accesses see the PTE we just wrote. Unlike userspace 217 * mappings, we can't tolerate spurious faults, so make sure 218 * the new PTE will be seen the first time. 219 */ 220 if (IS_ENABLED(CONFIG_PPC_BOOK3E_64) && is_kernel_addr(addr)) 221 mb(); 222 } 223 224 225 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 226 extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, 227 pte_t *ptep, pte_t entry, int dirty); 228 229 /* 230 * Macro to mark a page protection value as "uncacheable". 231 */ 232 233 #define _PAGE_CACHE_CTL (_PAGE_COHERENT | _PAGE_GUARDED | _PAGE_NO_CACHE | \ 234 _PAGE_WRITETHRU) 235 236 #define pgprot_noncached(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \ 237 _PAGE_NO_CACHE | _PAGE_GUARDED)) 238 239 #define pgprot_noncached_wc(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \ 240 _PAGE_NO_CACHE)) 241 242 #define pgprot_cached(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \ 243 _PAGE_COHERENT)) 244 245 #if _PAGE_WRITETHRU != 0 246 #define pgprot_cached_wthru(prot) (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \ 247 _PAGE_COHERENT | _PAGE_WRITETHRU)) 248 #else 249 #define pgprot_cached_wthru(prot) pgprot_noncached(prot) 250 #endif 251 252 #define pgprot_cached_noncoherent(prot) \ 253 (__pgprot(pgprot_val(prot) & ~_PAGE_CACHE_CTL)) 254 255 #define pgprot_writecombine pgprot_noncached_wc 256 257 struct file; 258 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 259 unsigned long size, pgprot_t vma_prot); 260 #define __HAVE_PHYS_MEM_ACCESS_PROT 261 262 #ifdef CONFIG_HUGETLB_PAGE 263 static inline int hugepd_ok(hugepd_t hpd) 264 { 265 #ifdef CONFIG_PPC_8xx 266 return ((hpd_val(hpd) & 0x4) != 0); 267 #else 268 /* We clear the top bit to indicate hugepd */ 269 return (hpd_val(hpd) && (hpd_val(hpd) & PD_HUGE) == 0); 270 #endif 271 } 272 273 static inline int pmd_huge(pmd_t pmd) 274 { 275 return 0; 276 } 277 278 static inline int pud_huge(pud_t pud) 279 { 280 return 0; 281 } 282 283 static inline int pgd_huge(pgd_t pgd) 284 { 285 return 0; 286 } 287 #define pgd_huge pgd_huge 288 289 #define is_hugepd(hpd) (hugepd_ok(hpd)) 290 #endif 291 292 #endif /* __ASSEMBLY__ */ 293 #endif 294