projects / pve-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 2b834b08 FG |
1 | From 40e1fa51bc8aa3df1d3a23711b5de62d8251bff5 Mon Sep 17 00:00:00 2001 |
| 2 | From: Seth Forshee <seth.forshee@canonical.com> | |
| 3 | Date: Wed, 3 May 2017 08:34:52 -0500 | |
| 4 | Subject: [PATCH 2/4] Revert "mm, ksm: convert write_protect_page() to use | |
| 5 | page_vma_mapped_walk()" | |
| 6 | ||
| 7 | This reverts commit 3000e033152a70fa139765b4dbb5baec46b1cc1b. | |
| 8 | ||
| 9 | Signed-off-by: Seth Forshee <seth.forshee@canonical.com> | |
| 10 | --- | |
| 11 | mm/ksm.c | 34 ++++++++++++++++------------------ | |
| 12 | 1 file changed, 16 insertions(+), 18 deletions(-) | |
| 13 | ||
| 14 | diff --git a/mm/ksm.c b/mm/ksm.c | |
| 15 | index 9dd2e58fb6dc..fed4afd8293b 100644 | |
| 16 | --- a/mm/ksm.c | |
| 17 | +++ b/mm/ksm.c | |
| 18 | @@ -856,35 +856,33 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page, | |
| 19 | pte_t *orig_pte) | |
| 20 | { | |
| 21 | struct mm_struct *mm = vma->vm_mm; | |
| 22 | - struct page_vma_mapped_walk pvmw = { | |
| 23 | - .page = page, | |
| 24 | - .vma = vma, | |
| 25 | - }; | |
| 26 | + unsigned long addr; | |
| 27 | + pte_t *ptep; | |
| 28 | + spinlock_t *ptl; | |
| 29 | int swapped; | |
| 30 | int err = -EFAULT; | |
| 31 | unsigned long mmun_start; /* For mmu_notifiers */ | |
| 32 | unsigned long mmun_end; /* For mmu_notifiers */ | |
| 33 | ||
| 34 | - pvmw.address = page_address_in_vma(page, vma); | |
| 35 | - if (pvmw.address == -EFAULT) | |
| 36 | + addr = page_address_in_vma(page, vma); | |
| 37 | + if (addr == -EFAULT) | |
| 38 | goto out; | |
| 39 | ||
| 40 | BUG_ON(PageTransCompound(page)); | |
| 41 | ||
| 42 | - mmun_start = pvmw.address; | |
| 43 | - mmun_end = pvmw.address + PAGE_SIZE; | |
| 44 | + mmun_start = addr; | |
| 45 | + mmun_end = addr + PAGE_SIZE; | |
| 46 | mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); | |
| 47 | ||
| 48 | - if (!page_vma_mapped_walk(&pvmw)) | |
| 49 | + ptep = page_check_address(page, mm, addr, &ptl, 0); | |
| 50 | + if (!ptep) | |
| 51 | goto out_mn; | |
| 52 | - if (WARN_ONCE(!pvmw.pte, "Unexpected PMD mapping?")) | |
| 53 | - goto out_unlock; | |
| 54 | ||
| 55 | - if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte)) { | |
| 56 | + if (pte_write(*ptep) || pte_dirty(*ptep)) { | |
| 57 | pte_t entry; | |
| 58 | ||
| 59 | swapped = PageSwapCache(page); | |
| 60 | - flush_cache_page(vma, pvmw.address, page_to_pfn(page)); | |
| 61 | + flush_cache_page(vma, addr, page_to_pfn(page)); | |
| 62 | /* | |
| 63 | * Ok this is tricky, when get_user_pages_fast() run it doesn't | |
| 64 | * take any lock, therefore the check that we are going to make | |
| 65 | @@ -894,25 +892,25 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page, | |
| 66 | * this assure us that no O_DIRECT can happen after the check | |
| 67 | * or in the middle of the check. | |
| 68 | */ | |
| 69 | - entry = ptep_clear_flush_notify(vma, pvmw.address, pvmw.pte); | |
| 70 | + entry = ptep_clear_flush_notify(vma, addr, ptep); | |
| 71 | /* | |
| 72 | * Check that no O_DIRECT or similar I/O is in progress on the | |
| 73 | * page | |
| 74 | */ | |
| 75 | if (page_mapcount(page) + 1 + swapped != page_count(page)) { | |
| 76 | - set_pte_at(mm, pvmw.address, pvmw.pte, entry); | |
| 77 | + set_pte_at(mm, addr, ptep, entry); | |
| 78 | goto out_unlock; | |
| 79 | } | |
| 80 | if (pte_dirty(entry)) | |
| 81 | set_page_dirty(page); | |
| 82 | entry = pte_mkclean(pte_wrprotect(entry)); | |
| 83 | - set_pte_at_notify(mm, pvmw.address, pvmw.pte, entry); | |
| 84 | + set_pte_at_notify(mm, addr, ptep, entry); | |
| 85 | } | |
| 86 | - *orig_pte = *pvmw.pte; | |
| 87 | + *orig_pte = *ptep; | |
| 88 | err = 0; | |
| 89 | ||
| 90 | out_unlock: | |
| 91 | - page_vma_mapped_walk_done(&pvmw); | |
| 92 | + pte_unmap_unlock(ptep, ptl); | |
| 93 | out_mn: | |
| 94 | mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); | |
| 95 | out: | |
| 96 | -- | |
| 97 | 2.7.4 | |
| 98 |