116 строки
4.6 KiB
C
116 строки
4.6 KiB
C
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/* To be include by pgtable-hash64.h only */
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/* Additional PTE bits (don't change without checking asm in hash_low.S) */
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#define _PAGE_SPECIAL 0x00000400 /* software: special page */
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#define _PAGE_HPTE_SUB 0x0ffff000 /* combo only: sub pages HPTE bits */
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#define _PAGE_HPTE_SUB0 0x08000000 /* combo only: first sub page */
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#define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */
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#define _PAGE_4K_PFN 0x20000000 /* PFN is for a single 4k page */
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/* For 64K page, we don't have a separate _PAGE_HASHPTE bit. Instead,
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* we set that to be the whole sub-bits mask. The C code will only
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* test this, so a multi-bit mask will work. For combo pages, this
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* is equivalent as effectively, the old _PAGE_HASHPTE was an OR of
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* all the sub bits. For real 64k pages, we now have the assembly set
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* _PAGE_HPTE_SUB0 in addition to setting the HIDX bits which overlap
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* that mask. This is fine as long as the HIDX bits are never set on
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* a PTE that isn't hashed, which is the case today.
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*
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* A little nit is for the huge page C code, which does the hashing
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* in C, we need to provide which bit to use.
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*/
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#define _PAGE_HASHPTE _PAGE_HPTE_SUB
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/* Note the full page bits must be in the same location as for normal
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* 4k pages as the same asssembly will be used to insert 64K pages
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* wether the kernel has CONFIG_PPC_64K_PAGES or not
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*/
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#define _PAGE_F_SECOND 0x00008000 /* full page: hidx bits */
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#define _PAGE_F_GIX 0x00007000 /* full page: hidx bits */
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/* PTE flags to conserve for HPTE identification */
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#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO)
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/* Shift to put page number into pte.
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*
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* That gives us a max RPN of 34 bits, which means a max of 50 bits
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* of addressable physical space, or 46 bits for the special 4k PFNs.
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*/
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#define PTE_RPN_SHIFT (30)
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#ifndef __ASSEMBLY__
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/*
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* With 64K pages on hash table, we have a special PTE format that
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* uses a second "half" of the page table to encode sub-page information
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* in order to deal with 64K made of 4K HW pages. Thus we override the
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* generic accessors and iterators here
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*/
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#define __real_pte(e,p) ((real_pte_t) { \
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(e), pte_val(*((p) + PTRS_PER_PTE)) })
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#define __rpte_to_hidx(r,index) ((pte_val((r).pte) & _PAGE_COMBO) ? \
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(((r).hidx >> ((index)<<2)) & 0xf) : ((pte_val((r).pte) >> 12) & 0xf))
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#define __rpte_to_pte(r) ((r).pte)
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#define __rpte_sub_valid(rpte, index) \
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(pte_val(rpte.pte) & (_PAGE_HPTE_SUB0 >> (index)))
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/* Trick: we set __end to va + 64k, which happens works for
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* a 16M page as well as we want only one iteration
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*/
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#define pte_iterate_hashed_subpages(rpte, psize, va, index, shift) \
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do { \
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unsigned long __end = va + PAGE_SIZE; \
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unsigned __split = (psize == MMU_PAGE_4K || \
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psize == MMU_PAGE_64K_AP); \
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shift = mmu_psize_defs[psize].shift; \
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for (index = 0; va < __end; index++, va += (1L << shift)) { \
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if (!__split || __rpte_sub_valid(rpte, index)) do { \
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#define pte_iterate_hashed_end() } while(0); } } while(0)
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#define pte_pagesize_index(mm, addr, pte) \
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(((pte) & _PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K)
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#define remap_4k_pfn(vma, addr, pfn, prot) \
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remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE, \
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__pgprot(pgprot_val((prot)) | _PAGE_4K_PFN))
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#ifdef CONFIG_PPC_SUBPAGE_PROT
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/*
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* For the sub-page protection option, we extend the PGD with one of
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* these. Basically we have a 3-level tree, with the top level being
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* the protptrs array. To optimize speed and memory consumption when
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* only addresses < 4GB are being protected, pointers to the first
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* four pages of sub-page protection words are stored in the low_prot
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* array.
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* Each page of sub-page protection words protects 1GB (4 bytes
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* protects 64k). For the 3-level tree, each page of pointers then
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* protects 8TB.
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*/
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struct subpage_prot_table {
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unsigned long maxaddr; /* only addresses < this are protected */
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unsigned int **protptrs[2];
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unsigned int *low_prot[4];
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};
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#undef PGD_TABLE_SIZE
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#define PGD_TABLE_SIZE ((sizeof(pgd_t) << PGD_INDEX_SIZE) + \
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sizeof(struct subpage_prot_table))
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#define SBP_L1_BITS (PAGE_SHIFT - 2)
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#define SBP_L2_BITS (PAGE_SHIFT - 3)
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#define SBP_L1_COUNT (1 << SBP_L1_BITS)
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#define SBP_L2_COUNT (1 << SBP_L2_BITS)
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#define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS)
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#define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS)
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extern void subpage_prot_free(pgd_t *pgd);
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static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd)
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{
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return (struct subpage_prot_table *)(pgd + PTRS_PER_PGD);
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}
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#endif /* CONFIG_PPC_SUBPAGE_PROT */
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#endif /* __ASSEMBLY__ */
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