projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 3df33f12 AK |
1 | /* |
| 2 | * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation. | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or | |
| 5 | * modify it under the terms of the GNU General Public License | |
| 6 | * as published by the Free Software Foundation; either version | |
| 7 | * 2 of the License, or (at your option) any later version. | |
| 8 | */ | |
| 9 | ||
| 10 | #include <linux/sched.h> | |
| 11 | #include <asm/pgalloc.h> | |
| 12 | #include <asm/tlb.h> | |
| 13 | ||
| 14 | #include "mmu_decl.h" | |
| 15 | #include <trace/events/thp.h> | |
| 16 | ||
| 17 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| 18 | /* | |
| 19 | * This is called when relaxing access to a hugepage. It's also called in the page | |
| 20 | * fault path when we don't hit any of the major fault cases, ie, a minor | |
| 21 | * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have | |
| 22 | * handled those two for us, we additionally deal with missing execute | |
| 23 | * permission here on some processors | |
| 24 | */ | |
| 25 | int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address, | |
| 26 | pmd_t *pmdp, pmd_t entry, int dirty) | |
| 27 | { | |
| 28 | int changed; | |
| 29 | #ifdef CONFIG_DEBUG_VM | |
| 30 | WARN_ON(!pmd_trans_huge(*pmdp)); | |
| 31 | assert_spin_locked(&vma->vm_mm->page_table_lock); | |
| 32 | #endif | |
| 33 | changed = !pmd_same(*(pmdp), entry); | |
| 34 | if (changed) { | |
| 35 | __ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry)); | |
| 36 | /* | |
| 37 | * Since we are not supporting SW TLB systems, we don't | |
| 38 | * have any thing similar to flush_tlb_page_nohash() | |
| 39 | */ | |
| 40 | } | |
| 41 | return changed; | |
| 42 | } | |
| 43 | ||
| 44 | int pmdp_test_and_clear_young(struct vm_area_struct *vma, | |
| 45 | unsigned long address, pmd_t *pmdp) | |
| 46 | { | |
| 47 | return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp); | |
| 48 | } | |
| 49 | /* | |
| 50 | * set a new huge pmd. We should not be called for updating | |
| 51 | * an existing pmd entry. That should go via pmd_hugepage_update. | |
| 52 | */ | |
| 53 | void set_pmd_at(struct mm_struct *mm, unsigned long addr, | |
| 54 | pmd_t *pmdp, pmd_t pmd) | |
| 55 | { | |
| 56 | #ifdef CONFIG_DEBUG_VM | |
| 57 | WARN_ON(pte_present(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp))); | |
| 58 | assert_spin_locked(&mm->page_table_lock); | |
| 59 | WARN_ON(!pmd_trans_huge(pmd)); | |
| 60 | #endif | |
| 61 | trace_hugepage_set_pmd(addr, pmd_val(pmd)); | |
| 62 | return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); | |
| 63 | } | |
| 64 | /* | |
| 65 | * We use this to invalidate a pmdp entry before switching from a | |
| 66 | * hugepte to regular pmd entry. | |
| 67 | */ | |
| 68 | void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, | |
| 69 | pmd_t *pmdp) | |
| 70 | { | |
| 71 | pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, 0); | |
| 72 | ||
| 73 | /* | |
| 74 | * This ensures that generic code that rely on IRQ disabling | |
| 75 | * to prevent a parallel THP split work as expected. | |
| 76 | */ | |
| 77 | kick_all_cpus_sync(); | |
| 78 | } | |
| 79 | ||
| 80 | static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot) | |
| 81 | { | |
| 82 | return __pmd(pmd_val(pmd) | pgprot_val(pgprot)); | |
| 83 | } | |
| 84 | ||
| 85 | pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot) | |
| 86 | { | |
| 87 | unsigned long pmdv; | |
| 88 | ||
| 89 | pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK; | |
| 90 | return pmd_set_protbits(__pmd(pmdv), pgprot); | |
| 91 | } | |
| 92 | ||
| 93 | pmd_t mk_pmd(struct page *page, pgprot_t pgprot) | |
| 94 | { | |
| 95 | return pfn_pmd(page_to_pfn(page), pgprot); | |
| 96 | } | |
| 97 | ||
| 98 | pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) | |
| 99 | { | |
| 100 | unsigned long pmdv; | |
| 101 | ||
| 102 | pmdv = pmd_val(pmd); | |
| 103 | pmdv &= _HPAGE_CHG_MASK; | |
| 104 | return pmd_set_protbits(__pmd(pmdv), newprot); | |
| 105 | } | |
| 106 | ||
| 107 | /* | |
| 108 | * This is called at the end of handling a user page fault, when the | |
| 109 | * fault has been handled by updating a HUGE PMD entry in the linux page tables. | |
| 110 | * We use it to preload an HPTE into the hash table corresponding to | |
| 111 | * the updated linux HUGE PMD entry. | |
| 112 | */ | |
| 113 | void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr, | |
| 114 | pmd_t *pmd) | |
| 115 | { | |
| 116 | return; | |
| 117 | } | |
| 118 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |