1024b246eSLinus Torvalds #ifndef _ALPHA_PGTABLE_H 2024b246eSLinus Torvalds #define _ALPHA_PGTABLE_H 3024b246eSLinus Torvalds 4024b246eSLinus Torvalds #include <asm-generic/4level-fixup.h> 5024b246eSLinus Torvalds 6024b246eSLinus Torvalds /* 7024b246eSLinus Torvalds * This file contains the functions and defines necessary to modify and use 8024b246eSLinus Torvalds * the Alpha page table tree. 9024b246eSLinus Torvalds * 10024b246eSLinus Torvalds * This hopefully works with any standard Alpha page-size, as defined 11024b246eSLinus Torvalds * in <asm/page.h> (currently 8192). 12024b246eSLinus Torvalds */ 13024b246eSLinus Torvalds #include <linux/mmzone.h> 14024b246eSLinus Torvalds 15024b246eSLinus Torvalds #include <asm/page.h> 16024b246eSLinus Torvalds #include <asm/processor.h> /* For TASK_SIZE */ 17024b246eSLinus Torvalds #include <asm/machvec.h> 18ec221208SDavid Howells #include <asm/setup.h> 19024b246eSLinus Torvalds 20024b246eSLinus Torvalds struct mm_struct; 21024b246eSLinus Torvalds struct vm_area_struct; 22024b246eSLinus Torvalds 23024b246eSLinus Torvalds /* Certain architectures need to do special things when PTEs 24024b246eSLinus Torvalds * within a page table are directly modified. Thus, the following 25024b246eSLinus Torvalds * hook is made available. 26024b246eSLinus Torvalds */ 27024b246eSLinus Torvalds #define set_pte(pteptr, pteval) ((*(pteptr)) = (pteval)) 28024b246eSLinus Torvalds #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval) 29024b246eSLinus Torvalds 30024b246eSLinus Torvalds /* PMD_SHIFT determines the size of the area a second-level page table can map */ 31024b246eSLinus Torvalds #define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT-3)) 32024b246eSLinus Torvalds #define PMD_SIZE (1UL << PMD_SHIFT) 33024b246eSLinus Torvalds #define PMD_MASK (~(PMD_SIZE-1)) 34024b246eSLinus Torvalds 35024b246eSLinus Torvalds /* PGDIR_SHIFT determines what a third-level page table entry can map */ 36024b246eSLinus Torvalds #define PGDIR_SHIFT (PAGE_SHIFT + 2*(PAGE_SHIFT-3)) 37024b246eSLinus Torvalds #define PGDIR_SIZE (1UL << PGDIR_SHIFT) 38024b246eSLinus Torvalds #define PGDIR_MASK (~(PGDIR_SIZE-1)) 39024b246eSLinus Torvalds 40024b246eSLinus Torvalds /* 41024b246eSLinus Torvalds * Entries per page directory level: the Alpha is three-level, with 42024b246eSLinus Torvalds * all levels having a one-page page table. 43024b246eSLinus Torvalds */ 44024b246eSLinus Torvalds #define PTRS_PER_PTE (1UL << (PAGE_SHIFT-3)) 45024b246eSLinus Torvalds #define PTRS_PER_PMD (1UL << (PAGE_SHIFT-3)) 46024b246eSLinus Torvalds #define PTRS_PER_PGD (1UL << (PAGE_SHIFT-3)) 47024b246eSLinus Torvalds #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) 48d016bf7eSKirill A. Shutemov #define FIRST_USER_ADDRESS 0UL 49024b246eSLinus Torvalds 50024b246eSLinus Torvalds /* Number of pointers that fit on a page: this will go away. */ 51024b246eSLinus Torvalds #define PTRS_PER_PAGE (1UL << (PAGE_SHIFT-3)) 52024b246eSLinus Torvalds 53024b246eSLinus Torvalds #ifdef CONFIG_ALPHA_LARGE_VMALLOC 54024b246eSLinus Torvalds #define VMALLOC_START 0xfffffe0000000000 55024b246eSLinus Torvalds #else 56024b246eSLinus Torvalds #define VMALLOC_START (-2*PGDIR_SIZE) 57024b246eSLinus Torvalds #endif 58024b246eSLinus Torvalds #define VMALLOC_END (-PGDIR_SIZE) 59024b246eSLinus Torvalds 60024b246eSLinus Torvalds /* 61024b246eSLinus Torvalds * OSF/1 PAL-code-imposed page table bits 62024b246eSLinus Torvalds */ 63024b246eSLinus Torvalds #define _PAGE_VALID 0x0001 64024b246eSLinus Torvalds #define _PAGE_FOR 0x0002 /* used for page protection (fault on read) */ 65024b246eSLinus Torvalds #define _PAGE_FOW 0x0004 /* used for page protection (fault on write) */ 66024b246eSLinus Torvalds #define _PAGE_FOE 0x0008 /* used for page protection (fault on exec) */ 67024b246eSLinus Torvalds #define _PAGE_ASM 0x0010 68024b246eSLinus Torvalds #define _PAGE_KRE 0x0100 /* xxx - see below on the "accessed" bit */ 69024b246eSLinus Torvalds #define _PAGE_URE 0x0200 /* xxx */ 70024b246eSLinus Torvalds #define _PAGE_KWE 0x1000 /* used to do the dirty bit in software */ 71024b246eSLinus Torvalds #define _PAGE_UWE 0x2000 /* used to do the dirty bit in software */ 72024b246eSLinus Torvalds 73024b246eSLinus Torvalds /* .. and these are ours ... */ 74024b246eSLinus Torvalds #define _PAGE_DIRTY 0x20000 75024b246eSLinus Torvalds #define _PAGE_ACCESSED 0x40000 76024b246eSLinus Torvalds 77024b246eSLinus Torvalds /* 78024b246eSLinus Torvalds * NOTE! The "accessed" bit isn't necessarily exact: it can be kept exactly 79024b246eSLinus Torvalds * by software (use the KRE/URE/KWE/UWE bits appropriately), but I'll fake it. 80024b246eSLinus Torvalds * Under Linux/AXP, the "accessed" bit just means "read", and I'll just use 81024b246eSLinus Torvalds * the KRE/URE bits to watch for it. That way we don't need to overload the 82024b246eSLinus Torvalds * KWE/UWE bits with both handling dirty and accessed. 83024b246eSLinus Torvalds * 84024b246eSLinus Torvalds * Note that the kernel uses the accessed bit just to check whether to page 85024b246eSLinus Torvalds * out a page or not, so it doesn't have to be exact anyway. 86024b246eSLinus Torvalds */ 87024b246eSLinus Torvalds 88024b246eSLinus Torvalds #define __DIRTY_BITS (_PAGE_DIRTY | _PAGE_KWE | _PAGE_UWE) 89024b246eSLinus Torvalds #define __ACCESS_BITS (_PAGE_ACCESSED | _PAGE_KRE | _PAGE_URE) 90024b246eSLinus Torvalds 91024b246eSLinus Torvalds #define _PFN_MASK 0xFFFFFFFF00000000UL 92024b246eSLinus Torvalds 93024b246eSLinus Torvalds #define _PAGE_TABLE (_PAGE_VALID | __DIRTY_BITS | __ACCESS_BITS) 94024b246eSLinus Torvalds #define _PAGE_CHG_MASK (_PFN_MASK | __DIRTY_BITS | __ACCESS_BITS) 95024b246eSLinus Torvalds 96024b246eSLinus Torvalds /* 97024b246eSLinus Torvalds * All the normal masks have the "page accessed" bits on, as any time they are used, 98024b246eSLinus Torvalds * the page is accessed. They are cleared only by the page-out routines 99024b246eSLinus Torvalds */ 100024b246eSLinus Torvalds #define PAGE_NONE __pgprot(_PAGE_VALID | __ACCESS_BITS | _PAGE_FOR | _PAGE_FOW | _PAGE_FOE) 101024b246eSLinus Torvalds #define PAGE_SHARED __pgprot(_PAGE_VALID | __ACCESS_BITS) 102024b246eSLinus Torvalds #define PAGE_COPY __pgprot(_PAGE_VALID | __ACCESS_BITS | _PAGE_FOW) 103024b246eSLinus Torvalds #define PAGE_READONLY __pgprot(_PAGE_VALID | __ACCESS_BITS | _PAGE_FOW) 104024b246eSLinus Torvalds #define PAGE_KERNEL __pgprot(_PAGE_VALID | _PAGE_ASM | _PAGE_KRE | _PAGE_KWE) 105024b246eSLinus Torvalds 106024b246eSLinus Torvalds #define _PAGE_NORMAL(x) __pgprot(_PAGE_VALID | __ACCESS_BITS | (x)) 107024b246eSLinus Torvalds 108024b246eSLinus Torvalds #define _PAGE_P(x) _PAGE_NORMAL((x) | (((x) & _PAGE_FOW)?0:_PAGE_FOW)) 109024b246eSLinus Torvalds #define _PAGE_S(x) _PAGE_NORMAL(x) 110024b246eSLinus Torvalds 111024b246eSLinus Torvalds /* 112024b246eSLinus Torvalds * The hardware can handle write-only mappings, but as the Alpha 113024b246eSLinus Torvalds * architecture does byte-wide writes with a read-modify-write 114024b246eSLinus Torvalds * sequence, it's not practical to have write-without-read privs. 115024b246eSLinus Torvalds * Thus the "-w- -> rw-" and "-wx -> rwx" mapping here (and in 116024b246eSLinus Torvalds * arch/alpha/mm/fault.c) 117024b246eSLinus Torvalds */ 118024b246eSLinus Torvalds /* xwr */ 119024b246eSLinus Torvalds #define __P000 _PAGE_P(_PAGE_FOE | _PAGE_FOW | _PAGE_FOR) 120024b246eSLinus Torvalds #define __P001 _PAGE_P(_PAGE_FOE | _PAGE_FOW) 121024b246eSLinus Torvalds #define __P010 _PAGE_P(_PAGE_FOE) 122024b246eSLinus Torvalds #define __P011 _PAGE_P(_PAGE_FOE) 123024b246eSLinus Torvalds #define __P100 _PAGE_P(_PAGE_FOW | _PAGE_FOR) 124024b246eSLinus Torvalds #define __P101 _PAGE_P(_PAGE_FOW) 125024b246eSLinus Torvalds #define __P110 _PAGE_P(0) 126024b246eSLinus Torvalds #define __P111 _PAGE_P(0) 127024b246eSLinus Torvalds 128024b246eSLinus Torvalds #define __S000 _PAGE_S(_PAGE_FOE | _PAGE_FOW | _PAGE_FOR) 129024b246eSLinus Torvalds #define __S001 _PAGE_S(_PAGE_FOE | _PAGE_FOW) 130024b246eSLinus Torvalds #define __S010 _PAGE_S(_PAGE_FOE) 131024b246eSLinus Torvalds #define __S011 _PAGE_S(_PAGE_FOE) 132024b246eSLinus Torvalds #define __S100 _PAGE_S(_PAGE_FOW | _PAGE_FOR) 133024b246eSLinus Torvalds #define __S101 _PAGE_S(_PAGE_FOW) 134024b246eSLinus Torvalds #define __S110 _PAGE_S(0) 135024b246eSLinus Torvalds #define __S111 _PAGE_S(0) 136024b246eSLinus Torvalds 137024b246eSLinus Torvalds /* 138024b246eSLinus Torvalds * pgprot_noncached() is only for infiniband pci support, and a real 139024b246eSLinus Torvalds * implementation for RAM would be more complicated. 140024b246eSLinus Torvalds */ 141024b246eSLinus Torvalds #define pgprot_noncached(prot) (prot) 142024b246eSLinus Torvalds 143024b246eSLinus Torvalds /* 144024b246eSLinus Torvalds * BAD_PAGETABLE is used when we need a bogus page-table, while 145024b246eSLinus Torvalds * BAD_PAGE is used for a bogus page. 146024b246eSLinus Torvalds * 147024b246eSLinus Torvalds * ZERO_PAGE is a global shared page that is always zero: used 148024b246eSLinus Torvalds * for zero-mapped memory areas etc.. 149024b246eSLinus Torvalds */ 150024b246eSLinus Torvalds extern pte_t __bad_page(void); 151024b246eSLinus Torvalds extern pmd_t * __bad_pagetable(void); 152024b246eSLinus Torvalds 153024b246eSLinus Torvalds extern unsigned long __zero_page(void); 154024b246eSLinus Torvalds 155024b246eSLinus Torvalds #define BAD_PAGETABLE __bad_pagetable() 156024b246eSLinus Torvalds #define BAD_PAGE __bad_page() 157024b246eSLinus Torvalds #define ZERO_PAGE(vaddr) (virt_to_page(ZERO_PGE)) 158024b246eSLinus Torvalds 159024b246eSLinus Torvalds /* number of bits that fit into a memory pointer */ 160024b246eSLinus Torvalds #define BITS_PER_PTR (8*sizeof(unsigned long)) 161024b246eSLinus Torvalds 162024b246eSLinus Torvalds /* to align the pointer to a pointer address */ 163024b246eSLinus Torvalds #define PTR_MASK (~(sizeof(void*)-1)) 164024b246eSLinus Torvalds 165024b246eSLinus Torvalds /* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */ 166024b246eSLinus Torvalds #define SIZEOF_PTR_LOG2 3 167024b246eSLinus Torvalds 168024b246eSLinus Torvalds /* to find an entry in a page-table */ 169024b246eSLinus Torvalds #define PAGE_PTR(address) \ 170024b246eSLinus Torvalds ((unsigned long)(address)>>(PAGE_SHIFT-SIZEOF_PTR_LOG2)&PTR_MASK&~PAGE_MASK) 171024b246eSLinus Torvalds 172024b246eSLinus Torvalds /* 173024b246eSLinus Torvalds * On certain platforms whose physical address space can overlap KSEG, 174024b246eSLinus Torvalds * namely EV6 and above, we must re-twiddle the physaddr to restore the 175024b246eSLinus Torvalds * correct high-order bits. 176024b246eSLinus Torvalds * 177024b246eSLinus Torvalds * This is extremely confusing until you realize that this is actually 178024b246eSLinus Torvalds * just working around a userspace bug. The X server was intending to 179024b246eSLinus Torvalds * provide the physical address but instead provided the KSEG address. 180024b246eSLinus Torvalds * Or tried to, except it's not representable. 181024b246eSLinus Torvalds * 182024b246eSLinus Torvalds * On Tsunami there's nothing meaningful at 0x40000000000, so this is 183024b246eSLinus Torvalds * a safe thing to do. Come the first core logic that does put something 184024b246eSLinus Torvalds * in this area -- memory or whathaveyou -- then this hack will have 185024b246eSLinus Torvalds * to go away. So be prepared! 186024b246eSLinus Torvalds */ 187024b246eSLinus Torvalds 188024b246eSLinus Torvalds #if defined(CONFIG_ALPHA_GENERIC) && defined(USE_48_BIT_KSEG) 189024b246eSLinus Torvalds #error "EV6-only feature in a generic kernel" 190024b246eSLinus Torvalds #endif 191024b246eSLinus Torvalds #if defined(CONFIG_ALPHA_GENERIC) || \ 192024b246eSLinus Torvalds (defined(CONFIG_ALPHA_EV6) && !defined(USE_48_BIT_KSEG)) 193024b246eSLinus Torvalds #define KSEG_PFN (0xc0000000000UL >> PAGE_SHIFT) 194024b246eSLinus Torvalds #define PHYS_TWIDDLE(pfn) \ 195024b246eSLinus Torvalds ((((pfn) & KSEG_PFN) == (0x40000000000UL >> PAGE_SHIFT)) \ 196024b246eSLinus Torvalds ? ((pfn) ^= KSEG_PFN) : (pfn)) 197024b246eSLinus Torvalds #else 198024b246eSLinus Torvalds #define PHYS_TWIDDLE(pfn) (pfn) 199024b246eSLinus Torvalds #endif 200024b246eSLinus Torvalds 201024b246eSLinus Torvalds /* 202024b246eSLinus Torvalds * Conversion functions: convert a page and protection to a page entry, 203024b246eSLinus Torvalds * and a page entry and page directory to the page they refer to. 204024b246eSLinus Torvalds */ 205024b246eSLinus Torvalds #ifndef CONFIG_DISCONTIGMEM 206024b246eSLinus Torvalds #define page_to_pa(page) (((page) - mem_map) << PAGE_SHIFT) 207024b246eSLinus Torvalds 208024b246eSLinus Torvalds #define pte_pfn(pte) (pte_val(pte) >> 32) 209024b246eSLinus Torvalds #define pte_page(pte) pfn_to_page(pte_pfn(pte)) 210024b246eSLinus Torvalds #define mk_pte(page, pgprot) \ 211024b246eSLinus Torvalds ({ \ 212024b246eSLinus Torvalds pte_t pte; \ 213024b246eSLinus Torvalds \ 214024b246eSLinus Torvalds pte_val(pte) = (page_to_pfn(page) << 32) | pgprot_val(pgprot); \ 215024b246eSLinus Torvalds pte; \ 216024b246eSLinus Torvalds }) 217024b246eSLinus Torvalds #endif 218024b246eSLinus Torvalds 219024b246eSLinus Torvalds extern inline pte_t pfn_pte(unsigned long physpfn, pgprot_t pgprot) 220024b246eSLinus Torvalds { pte_t pte; pte_val(pte) = (PHYS_TWIDDLE(physpfn) << 32) | pgprot_val(pgprot); return pte; } 221024b246eSLinus Torvalds 222024b246eSLinus Torvalds extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 223024b246eSLinus Torvalds { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; } 224024b246eSLinus Torvalds 225024b246eSLinus Torvalds extern inline void pmd_set(pmd_t * pmdp, pte_t * ptep) 226024b246eSLinus Torvalds { pmd_val(*pmdp) = _PAGE_TABLE | ((((unsigned long) ptep) - PAGE_OFFSET) << (32-PAGE_SHIFT)); } 227024b246eSLinus Torvalds 228024b246eSLinus Torvalds extern inline void pgd_set(pgd_t * pgdp, pmd_t * pmdp) 229024b246eSLinus Torvalds { pgd_val(*pgdp) = _PAGE_TABLE | ((((unsigned long) pmdp) - PAGE_OFFSET) << (32-PAGE_SHIFT)); } 230024b246eSLinus Torvalds 231024b246eSLinus Torvalds 232024b246eSLinus Torvalds extern inline unsigned long 233024b246eSLinus Torvalds pmd_page_vaddr(pmd_t pmd) 234024b246eSLinus Torvalds { 235024b246eSLinus Torvalds return ((pmd_val(pmd) & _PFN_MASK) >> (32-PAGE_SHIFT)) + PAGE_OFFSET; 236024b246eSLinus Torvalds } 237024b246eSLinus Torvalds 238024b246eSLinus Torvalds #ifndef CONFIG_DISCONTIGMEM 239024b246eSLinus Torvalds #define pmd_page(pmd) (mem_map + ((pmd_val(pmd) & _PFN_MASK) >> 32)) 240024b246eSLinus Torvalds #define pgd_page(pgd) (mem_map + ((pgd_val(pgd) & _PFN_MASK) >> 32)) 241024b246eSLinus Torvalds #endif 242024b246eSLinus Torvalds 243024b246eSLinus Torvalds extern inline unsigned long pgd_page_vaddr(pgd_t pgd) 244024b246eSLinus Torvalds { return PAGE_OFFSET + ((pgd_val(pgd) & _PFN_MASK) >> (32-PAGE_SHIFT)); } 245024b246eSLinus Torvalds 246024b246eSLinus Torvalds extern inline int pte_none(pte_t pte) { return !pte_val(pte); } 247024b246eSLinus Torvalds extern inline int pte_present(pte_t pte) { return pte_val(pte) & _PAGE_VALID; } 248024b246eSLinus Torvalds extern inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) 249024b246eSLinus Torvalds { 250024b246eSLinus Torvalds pte_val(*ptep) = 0; 251024b246eSLinus Torvalds } 252024b246eSLinus Torvalds 253024b246eSLinus Torvalds extern inline int pmd_none(pmd_t pmd) { return !pmd_val(pmd); } 254024b246eSLinus Torvalds extern inline int pmd_bad(pmd_t pmd) { return (pmd_val(pmd) & ~_PFN_MASK) != _PAGE_TABLE; } 255024b246eSLinus Torvalds extern inline int pmd_present(pmd_t pmd) { return pmd_val(pmd) & _PAGE_VALID; } 256024b246eSLinus Torvalds extern inline void pmd_clear(pmd_t * pmdp) { pmd_val(*pmdp) = 0; } 257024b246eSLinus Torvalds 258024b246eSLinus Torvalds extern inline int pgd_none(pgd_t pgd) { return !pgd_val(pgd); } 259024b246eSLinus Torvalds extern inline int pgd_bad(pgd_t pgd) { return (pgd_val(pgd) & ~_PFN_MASK) != _PAGE_TABLE; } 260024b246eSLinus Torvalds extern inline int pgd_present(pgd_t pgd) { return pgd_val(pgd) & _PAGE_VALID; } 261024b246eSLinus Torvalds extern inline void pgd_clear(pgd_t * pgdp) { pgd_val(*pgdp) = 0; } 262024b246eSLinus Torvalds 263024b246eSLinus Torvalds /* 264024b246eSLinus Torvalds * The following only work if pte_present() is true. 265024b246eSLinus Torvalds * Undefined behaviour if not.. 266024b246eSLinus Torvalds */ 267024b246eSLinus Torvalds extern inline int pte_write(pte_t pte) { return !(pte_val(pte) & _PAGE_FOW); } 268024b246eSLinus Torvalds extern inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } 269024b246eSLinus Torvalds extern inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } 270024b246eSLinus Torvalds extern inline int pte_special(pte_t pte) { return 0; } 271024b246eSLinus Torvalds 272024b246eSLinus Torvalds extern inline pte_t pte_wrprotect(pte_t pte) { pte_val(pte) |= _PAGE_FOW; return pte; } 273024b246eSLinus Torvalds extern inline pte_t pte_mkclean(pte_t pte) { pte_val(pte) &= ~(__DIRTY_BITS); return pte; } 274024b246eSLinus Torvalds extern inline pte_t pte_mkold(pte_t pte) { pte_val(pte) &= ~(__ACCESS_BITS); return pte; } 275024b246eSLinus Torvalds extern inline pte_t pte_mkwrite(pte_t pte) { pte_val(pte) &= ~_PAGE_FOW; return pte; } 276024b246eSLinus Torvalds extern inline pte_t pte_mkdirty(pte_t pte) { pte_val(pte) |= __DIRTY_BITS; return pte; } 277024b246eSLinus Torvalds extern inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= __ACCESS_BITS; return pte; } 278024b246eSLinus Torvalds extern inline pte_t pte_mkspecial(pte_t pte) { return pte; } 279024b246eSLinus Torvalds 280024b246eSLinus Torvalds #define PAGE_DIR_OFFSET(tsk,address) pgd_offset((tsk),(address)) 281024b246eSLinus Torvalds 282024b246eSLinus Torvalds /* to find an entry in a kernel page-table-directory */ 283024b246eSLinus Torvalds #define pgd_offset_k(address) pgd_offset(&init_mm, (address)) 284024b246eSLinus Torvalds 285024b246eSLinus Torvalds /* to find an entry in a page-table-directory. */ 286024b246eSLinus Torvalds #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) 287024b246eSLinus Torvalds #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address)) 288024b246eSLinus Torvalds 289024b246eSLinus Torvalds /* 290024b246eSLinus Torvalds * The smp_read_barrier_depends() in the following functions are required to 291024b246eSLinus Torvalds * order the load of *dir (the pointer in the top level page table) with any 292024b246eSLinus Torvalds * subsequent load of the returned pmd_t *ret (ret is data dependent on *dir). 293024b246eSLinus Torvalds * 294024b246eSLinus Torvalds * If this ordering is not enforced, the CPU might load an older value of 295024b246eSLinus Torvalds * *ret, which may be uninitialized data. See mm/memory.c:__pte_alloc for 296024b246eSLinus Torvalds * more details. 297024b246eSLinus Torvalds * 298024b246eSLinus Torvalds * Note that we never change the mm->pgd pointer after the task is running, so 299024b246eSLinus Torvalds * pgd_offset does not require such a barrier. 300024b246eSLinus Torvalds */ 301024b246eSLinus Torvalds 302024b246eSLinus Torvalds /* Find an entry in the second-level page table.. */ 303024b246eSLinus Torvalds extern inline pmd_t * pmd_offset(pgd_t * dir, unsigned long address) 304024b246eSLinus Torvalds { 305024b246eSLinus Torvalds pmd_t *ret = (pmd_t *) pgd_page_vaddr(*dir) + ((address >> PMD_SHIFT) & (PTRS_PER_PAGE - 1)); 306024b246eSLinus Torvalds smp_read_barrier_depends(); /* see above */ 307024b246eSLinus Torvalds return ret; 308024b246eSLinus Torvalds } 309024b246eSLinus Torvalds 310024b246eSLinus Torvalds /* Find an entry in the third-level page table.. */ 311024b246eSLinus Torvalds extern inline pte_t * pte_offset_kernel(pmd_t * dir, unsigned long address) 312024b246eSLinus Torvalds { 313024b246eSLinus Torvalds pte_t *ret = (pte_t *) pmd_page_vaddr(*dir) 314024b246eSLinus Torvalds + ((address >> PAGE_SHIFT) & (PTRS_PER_PAGE - 1)); 315024b246eSLinus Torvalds smp_read_barrier_depends(); /* see above */ 316024b246eSLinus Torvalds return ret; 317024b246eSLinus Torvalds } 318024b246eSLinus Torvalds 319024b246eSLinus Torvalds #define pte_offset_map(dir,addr) pte_offset_kernel((dir),(addr)) 320024b246eSLinus Torvalds #define pte_unmap(pte) do { } while (0) 321024b246eSLinus Torvalds 322024b246eSLinus Torvalds extern pgd_t swapper_pg_dir[1024]; 323024b246eSLinus Torvalds 324024b246eSLinus Torvalds /* 325024b246eSLinus Torvalds * The Alpha doesn't have any external MMU info: the kernel page 326024b246eSLinus Torvalds * tables contain all the necessary information. 327024b246eSLinus Torvalds */ 328024b246eSLinus Torvalds extern inline void update_mmu_cache(struct vm_area_struct * vma, 3294b3073e1SRussell King unsigned long address, pte_t *ptep) 330024b246eSLinus Torvalds { 331024b246eSLinus Torvalds } 332024b246eSLinus Torvalds 333024b246eSLinus Torvalds /* 334024b246eSLinus Torvalds * Non-present pages: high 24 bits are offset, next 8 bits type, 335024b246eSLinus Torvalds * low 32 bits zero. 336024b246eSLinus Torvalds */ 337024b246eSLinus Torvalds extern inline pte_t mk_swap_pte(unsigned long type, unsigned long offset) 338024b246eSLinus Torvalds { pte_t pte; pte_val(pte) = (type << 32) | (offset << 40); return pte; } 339024b246eSLinus Torvalds 340024b246eSLinus Torvalds #define __swp_type(x) (((x).val >> 32) & 0xff) 341024b246eSLinus Torvalds #define __swp_offset(x) ((x).val >> 40) 342024b246eSLinus Torvalds #define __swp_entry(type, off) ((swp_entry_t) { pte_val(mk_swap_pte((type), (off))) }) 343024b246eSLinus Torvalds #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 344024b246eSLinus Torvalds #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) 345024b246eSLinus Torvalds 346024b246eSLinus Torvalds #ifndef CONFIG_DISCONTIGMEM 347024b246eSLinus Torvalds #define kern_addr_valid(addr) (1) 348024b246eSLinus Torvalds #endif 349024b246eSLinus Torvalds 350024b246eSLinus Torvalds #define pte_ERROR(e) \ 351024b246eSLinus Torvalds printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e)) 352024b246eSLinus Torvalds #define pmd_ERROR(e) \ 353024b246eSLinus Torvalds printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e)) 354024b246eSLinus Torvalds #define pgd_ERROR(e) \ 355024b246eSLinus Torvalds printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e)) 356024b246eSLinus Torvalds 357024b246eSLinus Torvalds extern void paging_init(void); 358024b246eSLinus Torvalds 359024b246eSLinus Torvalds #include <asm-generic/pgtable.h> 360024b246eSLinus Torvalds 361024b246eSLinus Torvalds /* 362024b246eSLinus Torvalds * No page table caches to initialise 363024b246eSLinus Torvalds */ 364024b246eSLinus Torvalds #define pgtable_cache_init() do { } while (0) 365024b246eSLinus Torvalds 366024b246eSLinus Torvalds /* We have our own get_unmapped_area to cope with ADDR_LIMIT_32BIT. */ 367024b246eSLinus Torvalds #define HAVE_ARCH_UNMAPPED_AREA 368024b246eSLinus Torvalds 369024b246eSLinus Torvalds #endif /* _ALPHA_PGTABLE_H */ 370