Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 1 | /* To be include by pgtable-hash64.h only */ |
Arnd Bergmann | 88ced03 | 2005-12-16 22:43:46 +0100 | [diff] [blame] | 2 | |
Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 3 | /* Additional PTE bits (don't change without checking asm in hash_low.S) */ |
| 4 | #define _PAGE_SPECIAL 0x00000400 /* software: special page */ |
| 5 | #define _PAGE_HPTE_SUB 0x0ffff000 /* combo only: sub pages HPTE bits */ |
| 6 | #define _PAGE_HPTE_SUB0 0x08000000 /* combo only: first sub page */ |
| 7 | #define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */ |
| 8 | #define _PAGE_4K_PFN 0x20000000 /* PFN is for a single 4k page */ |
Benjamin Herrenschmidt | 3c726f8 | 2005-11-07 11:06:55 +1100 | [diff] [blame] | 9 | |
Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 10 | /* For 64K page, we don't have a separate _PAGE_HASHPTE bit. Instead, |
| 11 | * we set that to be the whole sub-bits mask. The C code will only |
| 12 | * test this, so a multi-bit mask will work. For combo pages, this |
| 13 | * is equivalent as effectively, the old _PAGE_HASHPTE was an OR of |
| 14 | * all the sub bits. For real 64k pages, we now have the assembly set |
| 15 | * _PAGE_HPTE_SUB0 in addition to setting the HIDX bits which overlap |
| 16 | * that mask. This is fine as long as the HIDX bits are never set on |
| 17 | * a PTE that isn't hashed, which is the case today. |
| 18 | * |
| 19 | * A little nit is for the huge page C code, which does the hashing |
| 20 | * in C, we need to provide which bit to use. |
| 21 | */ |
| 22 | #define _PAGE_HASHPTE _PAGE_HPTE_SUB |
Benjamin Herrenschmidt | 3c726f8 | 2005-11-07 11:06:55 +1100 | [diff] [blame] | 23 | |
Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 24 | /* Note the full page bits must be in the same location as for normal |
| 25 | * 4k pages as the same asssembly will be used to insert 64K pages |
| 26 | * wether the kernel has CONFIG_PPC_64K_PAGES or not |
| 27 | */ |
| 28 | #define _PAGE_F_SECOND 0x00008000 /* full page: hidx bits */ |
| 29 | #define _PAGE_F_GIX 0x00007000 /* full page: hidx bits */ |
| 30 | |
| 31 | /* PTE flags to conserve for HPTE identification */ |
| 32 | #define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO) |
| 33 | |
| 34 | /* Shift to put page number into pte. |
| 35 | * |
| 36 | * That gives us a max RPN of 34 bits, which means a max of 50 bits |
| 37 | * of addressable physical space, or 46 bits for the special 4k PFNs. |
| 38 | */ |
| 39 | #define PTE_RPN_SHIFT (30) |
Benjamin Herrenschmidt | 3c726f8 | 2005-11-07 11:06:55 +1100 | [diff] [blame] | 40 | |
Stephen Rothwell | ee7a76d | 2007-09-18 17:22:59 +1000 | [diff] [blame] | 41 | #ifndef __ASSEMBLY__ |
Benjamin Herrenschmidt | 3c726f8 | 2005-11-07 11:06:55 +1100 | [diff] [blame] | 42 | |
Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 43 | /* |
| 44 | * With 64K pages on hash table, we have a special PTE format that |
| 45 | * uses a second "half" of the page table to encode sub-page information |
| 46 | * in order to deal with 64K made of 4K HW pages. Thus we override the |
| 47 | * generic accessors and iterators here |
| 48 | */ |
| 49 | #define __real_pte(e,p) ((real_pte_t) { \ |
Benjamin Herrenschmidt | 6c16a74 | 2009-06-15 16:53:43 +0000 | [diff] [blame^] | 50 | (e), ((e) & _PAGE_COMBO) ? \ |
| 51 | (pte_val(*((p) + PTRS_PER_PTE))) : 0 }) |
Benjamin Herrenschmidt | c605782 | 2009-03-10 17:53:29 +0000 | [diff] [blame] | 52 | #define __rpte_to_hidx(r,index) ((pte_val((r).pte) & _PAGE_COMBO) ? \ |
| 53 | (((r).hidx >> ((index)<<2)) & 0xf) : ((pte_val((r).pte) >> 12) & 0xf)) |
| 54 | #define __rpte_to_pte(r) ((r).pte) |
| 55 | #define __rpte_sub_valid(rpte, index) \ |
| 56 | (pte_val(rpte.pte) & (_PAGE_HPTE_SUB0 >> (index))) |
| 57 | |
| 58 | /* Trick: we set __end to va + 64k, which happens works for |
| 59 | * a 16M page as well as we want only one iteration |
| 60 | */ |
| 61 | #define pte_iterate_hashed_subpages(rpte, psize, va, index, shift) \ |
| 62 | do { \ |
| 63 | unsigned long __end = va + PAGE_SIZE; \ |
| 64 | unsigned __split = (psize == MMU_PAGE_4K || \ |
| 65 | psize == MMU_PAGE_64K_AP); \ |
| 66 | shift = mmu_psize_defs[psize].shift; \ |
| 67 | for (index = 0; va < __end; index++, va += (1L << shift)) { \ |
| 68 | if (!__split || __rpte_sub_valid(rpte, index)) do { \ |
| 69 | |
| 70 | #define pte_iterate_hashed_end() } while(0); } } while(0) |
| 71 | |
| 72 | #define pte_pagesize_index(mm, addr, pte) \ |
| 73 | (((pte) & _PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K) |
| 74 | |
| 75 | #define remap_4k_pfn(vma, addr, pfn, prot) \ |
| 76 | remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE, \ |
| 77 | __pgprot(pgprot_val((prot)) | _PAGE_4K_PFN)) |
| 78 | |
Benjamin Herrenschmidt | 3c726f8 | 2005-11-07 11:06:55 +1100 | [diff] [blame] | 79 | |
Paul Mackerras | fa28237 | 2008-01-24 08:35:13 +1100 | [diff] [blame] | 80 | #ifdef CONFIG_PPC_SUBPAGE_PROT |
| 81 | /* |
| 82 | * For the sub-page protection option, we extend the PGD with one of |
| 83 | * these. Basically we have a 3-level tree, with the top level being |
| 84 | * the protptrs array. To optimize speed and memory consumption when |
| 85 | * only addresses < 4GB are being protected, pointers to the first |
| 86 | * four pages of sub-page protection words are stored in the low_prot |
| 87 | * array. |
| 88 | * Each page of sub-page protection words protects 1GB (4 bytes |
| 89 | * protects 64k). For the 3-level tree, each page of pointers then |
| 90 | * protects 8TB. |
| 91 | */ |
| 92 | struct subpage_prot_table { |
| 93 | unsigned long maxaddr; /* only addresses < this are protected */ |
| 94 | unsigned int **protptrs[2]; |
| 95 | unsigned int *low_prot[4]; |
| 96 | }; |
| 97 | |
| 98 | #undef PGD_TABLE_SIZE |
| 99 | #define PGD_TABLE_SIZE ((sizeof(pgd_t) << PGD_INDEX_SIZE) + \ |
| 100 | sizeof(struct subpage_prot_table)) |
| 101 | |
| 102 | #define SBP_L1_BITS (PAGE_SHIFT - 2) |
| 103 | #define SBP_L2_BITS (PAGE_SHIFT - 3) |
| 104 | #define SBP_L1_COUNT (1 << SBP_L1_BITS) |
| 105 | #define SBP_L2_COUNT (1 << SBP_L2_BITS) |
| 106 | #define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS) |
| 107 | #define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS) |
| 108 | |
| 109 | extern void subpage_prot_free(pgd_t *pgd); |
| 110 | |
| 111 | static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd) |
| 112 | { |
| 113 | return (struct subpage_prot_table *)(pgd + PTRS_PER_PGD); |
| 114 | } |
| 115 | #endif /* CONFIG_PPC_SUBPAGE_PROT */ |
| 116 | #endif /* __ASSEMBLY__ */ |